text:
\section{Introduction}\label{sec:introduction}}

\IEEEPARstart{B}{lockchain} was proposed as a supporting technology for Bitcoin \cite{nakamoto2019bitcoin}, the first decentralized cryptocurrency. After Bitcoin, other decentralized cryptocurrencies (e.g., Litecoin \cite {reed2017litecoin}, Ethereum \cite{wood2014ethereum}) quickly emerged. The blockchains of these cryptocurrencies use the Nakamoto's proof-of-work (PoW) protocol to build consensus among distributed nodes. Blockchain has, by now, become a cutting-edge technology in the fields of FinTech, Internet of Things (IoT), and supply chains \cite{du2019affordances,kshetri2017can,kouhizadeh2018blockchain}, thanks to its ability to enable Byzantine agreement over a permission-less decentralized network \cite{singh2016blockchain}.

A weakness of the current blockchains is the low on-chain transaction throughput. For example, the throughput of Bitcoin is around 5 $\sim$ 7 transactions per second (TPS), and that of Ethereum is around 40 TPS \cite{gobel2017increased}. Both are extremely low compared to around 110 TPS of PayPal and 1700 TPS of Visa. Its low transaction throughput hampers the widespread adoption of today's blockchain technology. A straightforward method to increase TPS is to enlarge the block size so that a block can carry more transactions. However, the propagation of large blocks in the network may incur huge delays that compromise the blockchains' security and integrity \cite{gervais2016security}, and thus it is not a good idea to increase the TPS by merely increasing the block size. Consequently, new consensus-building protocols and new specially deployed networking infrastructures have been proposed as solutions to increase the TPS of blockchains (see discussions of these related works in Section \ref{section:relatedWork}).

In this work, we put forth a new block propagation protocol to propagate large blocks containing a large number of transactions without increasing the block relay delay. Unlike the existing solution that requires changing the consensus-building protocol or deploying new network infrastructures, we build our block propagation protocol upon the compact-block relaying protocol that is already adopted by the current Bitcoin network \cite{corallo2017compact}. Compact-block relaying reduces the block relay delay by compressing blocks that contain transactions (around 250 Bytes each in Bitcoin) into compact blocks that contain transaction hashes (6 Bytes each). Therefore, compact-block relaying can include more transactions into each compact block while maintaining the same relay delay, thus increasing the TPS without compromising the blockchain's security.

In this paper, we further boost TPS by further increasing compact-block size including even more transaction hashes into each compact block. However, simply increasing compact-block size induces extra propagation delays that may compromise blockchain's security. We devise methods to keep the propagation delays at bay while increasing the compact-block size. We adopt a two-pronged approach: 1) we replace the store-and-forward compact-block relaying scheme with a cut-through forwarding scheme; 2) we apply rateless erasure codes to increase the efficiency of block propagation. The contributions of this work are listed as follows.
\begin{enumerate}
\item We put forth a new block propagation protocol that replaces the store-and-forward compact-block relaying scheme with a cut-through forwarding scheme. Our new cut-through compact-block relaying scheme can propagate large compact blocks without inducing extra relay. The original compact-block relaying \cite{corallo2017compact,ozisik2017graphene} is a store-and-forward scheme in which a whole compact block must be received before it is forwarded. With cut-through forwarding, a node receives small chunks of a compact block while forwarding earlier-received chunks, allowing reception and forwarding of a compact block to progress in parallel.
\item We apply rateless erasure codes to compact blocks. Rateless erasure codes allow the recovery of the source symbols using a subset of the encoded symbols. Instead of distributing the original compact block's source symbols, the compact block's source distributes the compact block's encoded symbols. Importantly, rateless erasure codes allow a peer to construct source symbols by retrieving the encoded symbols from multiple peers. Our coded design benefits from the peer-to-peer (P2P) network topology of the Bitcoin blockchain by efficiently utilizing the upload bandwidths of all peers \cite{gkantsidis2005network}.
\item We perform a theoretical analysis of our protocols assuming a simple linear network. The analysis results confirm that our protocols can obtain significant TPS gain. Moreover, to evaluate our protocols in a practical network, we implemented a Bitcoin network simulator. We simulated propagating huge compact blocks containing a large number of transaction hashes to improve TPS. Our results indicate that our block propagation protocols can increase TPS by 100x while maintaining the same propagation delay as the conventional block propagation protocols.
\end{enumerate}
Since our design is built upon compact-block relaying that has been implemented into the Bitcoin network, we believe our design can be readily deployed in the existing blockchain networks.

The rest of this paper is organized as follows. Section \ref{section:relatedWork} discusses related works. Section \ref{section:background} presents the background of blockchain. Section \ref{section:Uncoded} and Section \ref{section:Coded} introduce our uncoded and coded designs. Section \ref{section:analysis} analyzes the performance of our two-pronged approach. Section \ref{section:simulation} discusses our experimental results, and Section \ref{section:conclusion} concludes this work.

\section{Related Work}\label{section:relatedWork}
To improve the TPS of the Bitcoin blockchain, \cite{consensus2019, natoli2019deconstructing} changed the Nakamoto's PoW consensus protocol . These clean-slate designs modified data structures and many crypto functional components in the Bitcoin blockchain's consensus protocol. Consequently, these new consensus protocols are incompatible with the today's Bitcoin blockchain. By contrast, our work aims to increase TPS by redesigning the networking protocol without changing other key functional components. Furthermore, our work does not require the building of new network infrastructures. There has been little prior work along this line.

Ref. \cite{mccorry2020sok} discussed the shortcoming of the networking aspects of the Bitcoin blockchain. To reduce block propagation delay, \cite{corallo2017compact, ozisik2017graphene} devised compact-block relaying that transmits a compressed block consisting of the hashes of transactions in the block; transactions are transmitted (upon feedback from the receiver) only if they are missing at the receiver. Investigation in \cite{decker2013information} preemptively announce a block's availability before the complete reception of the whole block. Exploiting the multicasting capability of network nodes in blockchain, \cite{chawla2019velocity} employs fountain codes \cite{luby2002lt} to enable a full node to obtain a block from multiple peers. However, \cite{chawla2019velocity} still relies on store-and-forwarding rather than cut-through forwarding.

Several works advocated building new network infrastructures for speeding up the block propagation of the Bitcoin blockchain. For example, \cite{klarman2018bloxroute} used a blockchain distribution network (BDN) with high throughput servers to speed up the propagation of large blocks. In particular, \cite{klarman2018bloxroute} adopted cut-through forwarding within the BDN, but not at distributed blockchain nodes. The BDN approach requires building a new infrastructure controlled by a central authority, partially offsetting decentralized blockchain systems' many advantages. FIBRE (Fast Internet Bitcoin Relay Engine) in \cite{corallo2017fibre} is a transport-layer protocol that uses UDP with forward error correction to decrease the delays caused by packet loss. It also introduces data compression to reduce the amount of network traffic. Our work, focusing on the blockchain networking protocol \footnote{In the TCP/IP and OSI nomenclature, the blockchain networking protocol resides in the application layer. In this paper, we do not change IP or TCP protocol at all.}, is fully compatible with FIBRE and can be merged with it.

The idea of using cut-through forwarding to improve block propagation is also employed by Falcon \cite{falcon}. The differences between Falcon and our work here are as follows: i) Falcon implements cut-through forwarding on specially deployed relay nodes rather than on the existing blockchain nodes; ii) Falcon is a commercial project and there lacks performance analysis on its block propagation; iii) Falcon does not employ rateless erasure codes to increase the efficiency of block propagation.

\section{Bitcoin Blockchain Background}\label{section:background}
This section reviews the background for the Bitcoin blockchain, including its data structure, PoW consensus protocol, network topology, and block propagation protocols. After that, we present our compact block relaying scheme.

\subsection{Data Structure of Blockchain}
Blockchain is a decentralized append-only ledger for digital assets. A blockchain is replicated and shared among participants. The transactions in the system are contained in concatenated blocks in the blockchain. A block contains a header and multiple transactions. The state of a blockchain maintained by a participant changes according to the blocks in the blockchain.

We can write a block as $B = \left[ {H,{T_1},{T_2}, \cdots ,{T_K}} \right]$ where $H$ denotes the header, $\left\{ {{T_1},{T_2}, \cdots ,{T_K}} \right\}$ denotes the transactions in the block, and $K$ denotes the number of transactions in a block. The header $H$ contains the hash computed from the content of the preceding block, the Merkle root of the transactions in this block, a nonce generated by the PoW consensus protocol and a number indicating the mining target. Each block must refer to its preceding block by placing the hash of its preceding block in its header, and the blocks form a chain of blocks arranged in chronological order.

\subsection{PoW Consensus Protocol}
A consensus protocol coordinates the blockchain's updates to ensure chronological ordering of the blocks and to ensure the blockchain's integrity and consistency across geographically distributed nodes. Bitcoin \cite{nakamoto2019bitcoin}, as the first implementation of blockchain, introduces the Proof-of-Work (PoW) consensus protocol. Tens of thousands of distributed nodes adopt the PoW consensus protocol to achieve data consistency (i.e., ensuring the blockchains maintained by them are the same). Before adding blocks to the blockchain, a Bitcoin node has to prove that it has performed some work known as PoW. In essence, a node must find a nonce input to a hash function so that the hash value is less than a target number, as expressed by
\begin{equation}
\label{eqn:mininghash}
h\left( {n,p,m} \right) < D
\end{equation}
where $n$ is the nonce, $p$ is the hash of the preceding block, $m$ is the Merkle root of the transactions in the block, $h\left(  \cdot  \right)$ is a hash function, and $D$ is the mining target that is small with respect to the whole range of possible hash function outputs. The target $D$ is determined by a difficulty level set by the Bitcoin network. The header $H$ of a block contains $n$, $p$, $m$ and $D$. The difficulty level is dynamically tuned by the Bitcoin protocol, which ensures that the participating nodes, as a whole, produce an average of one block every ten minutes. The process of solving the PoW puzzle is called mining, and the nodes that perform the mining function are known as miners.

When other nodes receive a new block broadcasted from the miner, they verify the block locally and independently. The verification of a block can be divided into two parts: 1) the verification of the PoW solution, i.e., verifying whether the nonce $n$ contained in the block header fulfills (\ref{eqn:mininghash}) given the other block header's contents; 2) the verification of the transactions contained in the block body, i.e., verifying the validity of each transaction and verifying whether the Merkle root of all the transactions included in the block body is consistent with the Merkle root contained in the block header. If block passes verification, this block is appended to the local blockchain of the node.

\subsection{Blockchain Network Topology}
The network of the Bitcoin blockchain is based on an unstructured P2P network. The Bitcoin Core project \cite{bitcoincore} implements the Bitcoin networking protocol. When a node initializes, it attempts to discover a set of peers to establish outgoing or incoming\footnote{Outgoing connections are initiated by the node itself, and incoming connections are initiated by other nodes. When a Bitcoin node boots up, it asks the DNS seed nodes for a list of Bitcoin nodes' IP addresses. Then, it selects a subset of these addresses and initiates up to 8 outgoing connections. Meanwhile, this node's IP address will be logged and, going forward, sent to other nodes by the DNS seed nodes. This node will accept up to 117 incoming connections. Super nodes may establish more than 8 outgoing connections.} TCP connections. These connections are used for transaction and block propagation. Each node maintains a list of peers' IP addresses. According to the default protocol in the Bitcoin Core client, a node in the Bitcoin network initiates up to 8 outgoing connections and accepts up to 117 incoming connections. While the Bitcoin infrastructure does not support the discovery of the overall network topology — this is to secure the network from potential network attacks such as Eclipse\cite{heilman2015eclipse}, Sybil\cite{bissias2014sybil} — there have been works that acquire the network topology using the information in the Bitcoin blockchain protocol messages. A Bitcoin P2P Network Sniffer\cite{donet2014bitcoin} can connect to a Bitcoin node and listen to network events such as block broadcast or transaction broadcast. The collected data can be used to infer the size of the Bitcoin P2P network and the geographic distributions of nodes. We use this type of network topology information to model our blockchain network simulator, as discussed in Section \ref{section:simulation}.

\subsection{Transaction and Block Dissemination}
The network that supports the dissemination of transactions and blocks in the blockchain is a P2P network overlaid over the Internet. Each node keeps a replica of the complete blockchain. There is no central coordinator to ensure the consistency of the replicas across the different nodes. Rather, the nodes use a simple gossip protocol to propagate messages containing transactions and blocks to update and synchronize their ledger replicas.

Let us first describe the block propagation protocol of standard relaying (SR) as illustrated in Fig. \ref{fig_1}(a). To avoid unnecessary block forwarding, a peer does not forward blocks to its peer immediately. Instead, an inv \cite{decker2013information} containing a summary of the blocks available—specifically, hashes of the blocks—is sent to a neighbor (node B in Fig. \ref{fig_1}(a)). When a node receives an inv message, it issues a getdata message to the sender, only requesting for blocks that it does not have. The SR protocol, although simple, is inefficient and incurs large propagation delay and has low transaction throughput.

Compact-block relaying (CBR) \cite{corallo2017compact}, as illustrated in Fig. \ref{fig_1}(b), is a solution to decrease propagation delay. CBR also announces blocks available at the sender through an inv. However, upon receiving a getdata message, the sender only returns a compact block containing a summary of the transactions included in the entire block (i.e., the hashes of the transactions). The receiver then only requests for the transactions in the block that it does not have (blocktxn in Fig. \ref{fig_1}(b)) rather than the whole block (block in Fig. \ref{fig_1}(a)). Since blocktxn contains only a fraction of all transactions in a block, the bandwidth needed for data propagation is reduced. Although CBR decreases the propagation delay, the sender still needs to have the whole compact block in hand before relaying it. This relaying is called "stored-and-forward". While store-and-forward relaying works well for small compact blocks, if we intend to increase the block size to boost TPS, the compact blocks become large themselves. When relaying compact blocks of large size, the store-and-forward CBR can incur large latency.

\begin{figure*}[!t]
\centering
\includegraphics[width=5in]{Figure1.pdf}
\caption{The forwarding of a block over two hops by three different block propagation protocols: (a) the original block propagation protocol; (b) the compact block relaying protocol; (c) the cut-through compact block relaying.}
\label{fig_1}
\end{figure*}

\section{Uncoded Design: Compact-Block Relaying with Cut-through Forwarding}\label{section:Uncoded}
This section presents the design of a new CBR protocol. Although the original store-and-forward CBR can increase the TPS to some extent, according to our experiment result (see Section \ref{section:simulation}.2), using the store-and-forward CBR to propagate compact blocks of large size can lead to large propagation delays.

As illustrated in Fig. \ref{fig_1}(c), the main essence of our new CBR protocol is to allow parallel relaying of large compact blocks. A node P forwards a compact block to another node Q in small chunks. Node Q then forwards the earlier chunks to node R as later chunks are received. In particular, node Q does not wait for all the chunks of the compact block to be received before forwarding the earlier received chunks. We refer to our block propagation protocol as cut-through compact-block relaying (Cut-through CBR). We elaborate on the details of Cut-through CBR in the following.

For a block $B = \left[ {H,{T_1},{T_2}, \cdots ,{T_K}} \right]$, the original CBR constructs the compact block as ${B_c} = \left[ {H,{I_1},{I_2}, \cdots ,{I_K}} \right]$, where $H$ is the header of the block and ${I_k}$ is a the 6-byte short hash of transaction ${T_k}$. When relaying a compact block, instead of sending out the inv message first as in the original CBR, the sender node in our Cut-through CBR immediately broadcasts the block header $H$ to its adjacent peers. In particular, our Cut-through CBR requires the nodes to check whether the block header is valid. Specifically, after receiving the block header, the nodes need to perform the header validation by checking whether the nonce contained in $H$ fulfills (\ref{eqn:mininghash}) to validate the PoW solution. Compared with the full validation\footnote{In the original CBR for Bitcoin, the full validation of a compact block consists of the header validation and the transaction validation. The header validation checks whether the PoW is valid, while the transaction validation check whether the transactions conveyed by the compact block are valid.} of a compact block in the original CBR, this header validation is provisional. As soon as the header $H$ is received, the provisional header validation can begin before the whole compact block is received, consuming much less computation time. This provisional header verification can prevent malicious nodes from generating fake blocks at low cost. Furthermore, to maintain security, if a node in our Cut-through CBR finds an invalid transaction later during the compact block relaying, this node will suspend the compact-block relaying and alert its peers by sending an abort message, as explained in the following.

To further elaborate our protocol, as illustrated in Fig. 1(c), we consider a scenario in which a peer P sends out $H$, and peer Q is one of P's neighbors. After peer Q receives $H$ from peer P, peers Q and P execute the following operational steps in order:
\begin{enumerate}
\item Peer Q first checks whether the received $H$ is in its local pool. If it is, peer Q does nothing and discards $H$. If it is not, peer Q sets peer P as this block's seed peer and goes to the next operation.
\item Peer Q performs the provisional header validation of $H$ to verify the PoW solution. If the provisional header validation passes, peer Q puts $H$ into its local pool and broadcasts it to all adjacent peers (except the peer P). Furthermore, peer Q sends a query message to peer P to ask for the transaction hashes in the compact block and then goes to step 4). If the provisional header validation is not fulfilled, peer Q suspends all the operations related to this block.
\item After receiving the query message from peer Q, peer P sends peer Q the transaction hashes in chunks. Specifically, every consecutive $M$ transaction hashes are grouped into a hash chunk, and the hash chunks are sent one after another. Peer P keeps sending the hash chunks to peer Q as long as it has any of the hash chunks (either generated from peer P itself if peer P is the miner of this block or received from peer P's seed peers).
\item Peer Q receives the hash chunks sent from peer P and performs the chunk validation by validating the transactions indexed by the transaction hashes. In case peer Q lacks some of the transactions on its local storage, it requests the missing transactions from other nodes by sending the getblocktxn message, as in the original CBR \cite{corallo2017compact}. Meanwhile, peer Q also listens for query messages from other peers who treat peer Q as their seed peer of the compact block. As illustrated in Fig. \ref{fig_1}(c), peer Q receives a peer R' query message, peer Q then answers peer R with its validated hash chunks.
\item If peer Q finds an invalid transaction during the chunk validation, it will suspend the propagation of this compact block. Furthermore, it will clear all the compact-block related messages related to the compact block from its storage and send an abort message to alert its peers that query for the same compact block. If all transactions pass validation, this block is valid, and peer Q reconstructs the block and appends it to the blockchain.
\end{enumerate}
Our Cut-through CBR protocol processes the reception and the forwarding of a compact block's small chunks in parallel, in a pipeline manner. It thus speeds up the propagation of a huge compact block.

\section{Coded Design: Leveraging Rateless Coding}\label{section:Coded}
In Cut-through CBR, a peer can only retrieve the compact block's chunks from one peer. This section leverages rateless erasure codes to allow a peer to retrieve the chunks from multiple peers. This coded design incorporates fountain codes \cite{luby2002lt} (a kind of rateless erasure codes) into Cut-through CBR to efficiently utilize the upload bandwidths of multiple peers \cite{gkantsidis2005network}.

In the coded design, instead of sending $M$ transaction hash chunks $\left\{ {{p_1},{p_2}, \cdots ,{p_M}} \right\}$, the block miner performs fountain coding over the hash chunks to generate the equal-size coded symbols $\{ {x_1},{x_2}, \cdots {x_i}, \cdots \}$ according to the coding scheme proposed in \cite{wang2007network}. Specifically, the coding scheme chooses a set of $M$ coding cofficients ${C_i} = \{ {c_1},{c_2},{c_3} \ldots ,{c_M}\}$ in a finite field. Then we have
\begin{equation}
	\label{eqn:networkCoding}
	{x_i} = \sum\limits_{j = 1}^M {{c_j}{p_j}}
\end{equation}
We refer to $\{ {x_1},{x_2} \ldots ,{x_i},...\}$ as the coded hash chunks. Then the miner sends these coded hash chunks (${C_i}$ is also sent out together with ${x_i}$) to the peers querying this compact block. After receiving a coded hash chunk, a peer relays it to some of its peers querying for the same compact block. In this way, each node can be the seed peer of a number of its peers during the compact-block relaying process. Furthermore, fountain code guarantees that the likelihood of decoding a set of coded chunks into the compact-block approaches $1$ when $n = M(1 + \varepsilon)$ coded chunks have been received, where $\varepsilon$ is typically less than $2\%$ \cite{luby2002lt}.

We name the rateless-erasure-codes enhanced protocol Coded Cut-through CBR. We describe the operational steps of Coded Cut-thought CBR using an example network topology illustrated in Fig. \ref{fig_2}, where peer P is a miner with two neighbor peers: peer Q and peer S. In particular, peer Q and peer S are also the neighbors of each other. After peer P mines a block, it sends the block header $H$ to peer Q. After peer Q receives $H$, peers Q and P execute the following operational steps in order (these operational steps are illustrated in Fig. \ref{fig_3}):
\begin{enumerate}
	\item Peer Q first checks whether it has the block using in $H$. If it has the block, peer Q does nothing. If it does not have the block, peer Q sets peer P as this block's seed peer and goes to step 2.
	\item Peer Q performs the provisional header validation over $H$ to validate the PoW. If the PoW is valid, peer Q puts $H$ into its local pool and relays $H$ to its neighbor peer (in this case, its neighbor peer is peer S). After that, peer Q sends a query message to peer P querying the transaction hashes. If the PoW is not valid, peer Q aborts and does not relay this compact block.
	\item After receiving the query message from peer Q, peer P sends peer Q the coded hash chunks generated by fountain coding. Specifically, peer P keeps generating and sending the coded hash chunks ${x_i},i = 1,2, \cdots$ to peer Q until peer Q sends back an ACK message announcing that it receives sufficient coded hash chunks to decode the fountain code. In Fig. 3, peer P sends a total of $n$ coded hash chunks to peer Q.
	\item When receiving coded hash chunks ${x_i},1 \le i \le n$ from peer P, peer Q also relays its received coded hash chunks to peer S that queries the chunks after receiving $H$ from peer Q.
	\item After receiving the ACK, peer P stops sending its coded hash chunks to peer Q. Peer P then sends $H$ to peer S seeking to be a potential seed peer of peer S. Once receiving the query message sent from peer S, peer P starts generating and sending coded hash chunk ${x_i},i \ge n + 1$ to peer S.
	\item At this time, peer S has two seed peers of this compact block, namely, peer P and peer Q. Peer S keeps receiving the coded hash chunks sent from either peer P or peer Q. Once it gets sufficient coded hash chunks for decoding the compact block, peer S sends the ACK to peer P and peer Q one after another. In Fig. \ref{fig_3}, peer S receives $j,j \le n$ coded hash chunks from peer Q and $k,k \le n^{'}$ coded hash chunks from peer P. Here, for peer S, we have $j + k = n^{'}$, $n^{'}$ is the number of coded hash chunks required to decode the compact block.
\end{enumerate}
After receiving sufficient coded chunks, peer Q and peer S decode the fountain-code and validate all transactions. If all transactions pass validation, each peer reconstructs this block and appends it to the blockchain.

\begin{figure}[!t]
	\centering
	\includegraphics[width=3.5in]{Figure2.pdf}

	\caption{The network topology of three nodes (peer P, peer Q, and peer S) relaying one compact block using Coded Cut-through CBR. Node P is the miner of the compact block in this example.}
	\label{fig_2}
\end{figure}

In Fig. \ref{fig_3}, if the peer Q's upload bandwidth is much lower than that of other peers, then we have $j \ll n$. In this case, if using standard relaying (SR) (see Section 3.4) and Cut-through CBR, peer S can do nothing except receiving the information sent from peer Q. In Coded Cut-through CBR, however, the available upload bandwidth of other nodes (in this case, the available upload bandwidth of peer P) can be further used to relay the compact block to peer S. Hence, Coded Cut-through CBR leverages the P2P network topology to use the upload bandwidths of all peers efficiently. Thus, it can speed up the information propagation in the Bitcoin blockchain. We theoretically analyze our Cut-through CBR and Coded Cut-through CBR protocols to validate their potential gains in the next section.

\begin{figure}[!t]
	\centering
	\includegraphics[width=3.5in]{Figure3.pdf}

	\caption{The illustration for Coded Cut-through CBR.}
	\label{fig_3}
\end{figure}

\section{Performance Analysis}
This section presents the effect of the block propagation delay on the Bitcoin blockchain's TPS and the analysis of the block propagation latencies of the four propagation protocols (SR, CBR, Cut-through CBR and Coded Cut-through CBR).
\label{section:analysis}
\subsection{The effect of the block propagation delay on TPS}
We first calculate the TPS of the Bitcoin blockchain. We denote the block size by ${S_{block}}$, the average transaction size by ${S_{transaction}}$, and the inter-block generation time by ${T_B}$. The TPS of the blockchain is calculated as
\begin{equation}
	\label{eqn:TPSCal}
	TPS = \frac{{{S_{block}}}}{{{S_{transaction}}{T_B}}}
\end{equation}
In Bitcoin, we have ${S_{block}} = 1$ MB, ${S_{transaction}} = 380.04$ B and ${T_B} = 600$ s, and thus the TPS of Bitcoin is
$TP{S_{Bitcoin}} = \frac{{1048576}}{{380.04*600}} \approx 4.6$.

According to (\ref{eqn:TPSCal}), a simple way to increase the TPS is to increase ${S_{block}}$ or to decrease ${T_B}$. However, merely increasing ${S_{block}}$ or decreasing ${T_B}$ cannot increase the TPS, as explained below.  It takes a certain time to propagate a block over the p2p network of the blockchain. Let $L$ denote the time latency of propagating a block from the miner to almost all nodes in the whole network (e.g., $90\%$ of the nodes in the network). First, the increase of ${S_{block}}$ leads to an increase of $L$, which, in turn, may compromise the security of the blockchain \cite{gervais2016security}. In particular, $L$ should be sufficiently smaller than ${T_B}$. The closer $L$ gets to ${T_B}$, the more forks, more orphan blocks, and more chain re-organizations there will be. According to \cite{klarman2018bloxroute}, the probability for a fork to occur at another miner is approximately
\begin{equation}
	\label{eqn:forkCal}
	P(fork|{T_B} = 600) = 1 - {e^{\frac{{ - L}}{{{T_B}}}}}
\end{equation}
In the extreme case, the system will be exposed to security vulnerabilities such as double-spend attacks\cite{gervais2016security}. Motivated by (\ref{eqn:forkCal}), this paper uses a performance metric, propagation divergence factor, to quantify the effect of block propagation latency. \\
\textsl{ \textbf{Propagation Divergence Factor}}: The propagation divergence factor is defined as
\begin{equation}
	\label{eqn:PDF}
	\Delta  = \frac{L}{{{T_B}}}
\end{equation}
where $\Delta  \ge 0$  since $L \ge 0$. The larger $\Delta $, the larger the divergence (e.g., asynchronies and discrepancies) is among the different local replicas of the blockchain maintained by different nodes. In the extreme case where $L = 0$, we have $\Delta  = 0$ meaning that the blockchains of all the nodes in the network become instantaneously synchronized.

The main purpose of our protocols is to suppress the increase of $L$ when we increase ${S_{block}}$. In this way, we can boost the TPS of the Bitcoin blockchain while maintaining the security of the blockchain. According to (\ref{eqn:TPSCal}), increasing ${S_{block}}$ by 100x can increase the TPS by 100x, yielding $TP{S_{Bitcoin}} \approx 460$. In the next subsection, we analyze the block propagation latency $L$ caused by different block propagation protocols.

\begin{figure}[!t]
	\centering
	\includegraphics[width=3.5in]{Figure4.pdf}

	\caption{A simple linear network with $n+1$ nodes.}
	\label{fig_4}
\end{figure}

\subsection{The comparison of the block propagation latency using different protocols}
We next analyze the block propagation latencies of the four propagation protocols (SR, CBR, Cut-through CBR and Coded Cut-through CBR). For simple illustration, we consider a network with a linear topology consisting of
$n + 1$ nodes as shown in Fig. \ref{fig_4}. We assume the communication bandwidth of each node is $B$. We calculate the block propagation latency of propagating a block from node $0$ to node $n$ in this linear network.

Let ${S_{ip}}$ be the IP packet's payload size and ${S_h}$ be the IP packet header size. When using SR to propagate blocks, with IP packet fragmentation, a block needs to be cut into $\frac{{{S_{block}}}}{{{S_{ip}}}}$ IP packets. The block propagation latency from node $0$ to node $n$ caused under the SR protocol is given by
\begin{equation}
	\label{eqn:L_SR}
	{L_{SR}} = \frac{{n({S_{block}} + {O_b})}}{B} + n{V_b}
\end{equation}
where ${O_b} = \frac{{{S_{block}}}}{{{S_{ip}}}}{S_h}$ is the overhead caused by the IP packet fragmentation when relaying a block over one hop between two neighbor nodes, and ${V_b}$ is the time incurred by a full-block validation process.

Let ${N_t}$ be the number of transactions in a block. The size of a compact block is given by
\begin{equation}
	\label{eqn:Size_CBR}
	{S_{cb}} = {N_t}{S_I} + {S_{h\_cb}}
\end{equation}
where ${S_I}$ is the size of a short transaction hash and ${S_{h\_cb}}$ is the size of the compact-block header. When using CBR, a compact block needs to be cut into $\frac{{{S_{cb}}}}{{{S_{ip}}}}$ IP packets. Recall that in Bitcoin, nodes have 10 min (${T_B} = 10$ min) to propagate their collected transactions to all other nodes before the transactions are announced in the latest block. For the sake of simplicity, we assume that all transactions within the block are already available at the nodes given the long duration of 10 min, and there is no need to go and fetch the transactions. In fact, \cite{corallo2017compact} found that in the Bitcoin network, before a new block is found, transactions obtained by all nodes are almost synchronized. Then, the block propagation latency from node $0$ to node $n$ under CBR is given by
\begin{equation}
	\label{eqn:L_CBR}
	{L_{CBR}} = \frac{{n({S_{cb}} + {O_{cb}})}}{B} + n{V_b}
\end{equation}
where ${O_{cb}} = \frac{{{S_{cb}}}}{{{S_{ip}}}}{S_h}$ is the overhead caused by the IP packet fragment when relaying a compact block over one hop.

From (\ref{eqn:L_SR}) and (\ref{eqn:L_CBR}), we can see that CBR speeds up the block propagation significantly, since ${S_{cb}} \ll {S_b}$. In particular, if ${V_b}$ is negligible, CBR can reduce the block propagation latency by $\frac{{{S_{block}}}}{{{S_{cb}}}}$ times compared with SR. However, ${L_{CBR}}$ is still proportional to $n{S_{cb}}$. Consequently, the increase of ${S_{cb}}$ can lead a significant increase of ${L_{CBR}}$, making it impossible to increase TPS by inserting more transaction hashes into each compact block.

We next analyze the propagation latency of the cut-through forwarding scheme used in both Cut-through CBR and Coded Cut-through CBR. Let $k \ge 1$ be the number of chunks per compact block and ${S_{ch}}$ be the chunk size. We thus have ${S_{cb}} = k{S_{ch}}$. Let ${V_{ch}} = \frac{{{V_b}}}{k}$ be the time needed to validate the transactions in a chunk and ${O_{ch}}$ be the overhead of IP packet fragmentation when relaying a chunk over one hop. The block propagation latency from node $0$ to node $n$ under Cut-through CBR is given by
\begin{equation}
	\label{eqn:L_CT}
	{L_{CT - CBR}} = k(\frac{{{S_{ch}} + {O_{ch}}}}{B} + {V_{ch}}) + (n - 1)(\frac{{{S_{ch}} + {O_{ch}}}}{B} + {V_{ch}})
\end{equation}
The first term of (\ref{eqn:L_CT}) is the block propagation latency in the first hop (from node $0$ to node $n$) and the second term of (\ref{eqn:L_CT}) is the block propagation latency over the rest of the hops (from node $0$ to node $n$). We further investigate the effect of $k$ when using the cut-through forwarding scheme in the following two cases:

If $1 \le k \le \frac{{{S_{cb}}}}{{{S_{ip}}}}$, then we have $\frac{{{S_{cb}}}}{k} = {S_{ch}} \ge {S_{ip}}$, which means that we need to perform IP packet fragmentation over each chunk. Specifically, a chunk needs to be cut into $\frac{{{S_{ch}}}}{{{S_{ip}}}}$ IP packets and ${O_{ch}} = \frac{{{S_{ch}}}}{{{S_{ip}}}}{S_h} = \frac{{{O_{cb}}}}{k}$. From (\ref{eqn:L_CT}), we then have
\begin{equation}
	\label{eqn:L_CT-1}
	{L_{CT - CBR}} = (\frac{{{S_{cb}} + {O_{cb}}}}{B} + {V_b}) + \frac{{(n - 1)}}{k}(\frac{{{S_{cb}} + {O_{cb}}}}{B} + {V_b})
\end{equation}
Compared with (\ref{eqn:L_CBR}), the increase of $k$ in (\ref{eqn:L_CT-1}) will significantly reduce the block propagation latency. We denote the gain obtained from the cut-through forwarding scheme over the original CBR by ${g_{CT - CBR}} = {L_{CBR}} - {L_{CT - CBR}}$. The gain ${g_{CT - CBR}}$ can be computed as
\begin{equation}
	\label{eqn:g_CT-1}
	\begin{array}{l}
	{g_{CT - CBR}} = \frac{{n({S_{cb}} + {O_{cb}})}}{B} + n{V_b} - (k + n - 1)(\frac{{{S_{ch}} + {O_{ch}}}}{B} + {V_{ch}})\\
	= \frac{{n({S_{cb}} + {O_{cb}}) - (k + n - 1)(\frac{{{S_{cb}}}}{k} + \frac{{{O_{cb}}}}{k})}}{B} + n{V_b} - (k + n - 1)\frac{{{V_b}}}{k}\\
	= (1 - \frac{1}{k})(n - 1)(\frac{{({S_{cb}} + {O_{cb}})}}{B} + {V_b})
	\end{array}
\end{equation}
Note that since $k \ge 1$ and $1 - \frac{1}{k} > 0$, we have ${g_{CT - CBR}} > 0$. That is, the cut-through forwarding scheme outperforms the traditional CBR when $1 \le k \le \frac{{{S_{cb}}}}{{{S_{ip}}}}$. Eqn. (\ref{eqn:L_CBR}) and Eqn. (\ref{eqn:g_CT-1}) lead to several conclusions:
\begin{enumerate}
	\item When $k = 1$ or $n = 1$, both Cut-through CBR and Coded Cut-through CB downgrade to CBR.
	\item When $k$ is fixed, the gain obtained from the cut-through forwarding scheme becomes larger with the increase of ${S_{cb}}$. The cut-through forwarding scheme hence is expected to perform well even if ${S_{cb}}$ is very large.
	\item When ${S_{cb}}$ is fixed, ${L_{CT - CBR}}$ is a decreasing function of $k$. The increase of $k$ achieves lower propagation latency.
\end{enumerate}

If $k > \frac{{{S_{cb}}}}{{{S_{ip}}}}$, then we have $\frac{{{S_{cb}}}}{k} = {S_{ch}} < {S_{ip}}$. In this case, we use one IP packet to transmit one chunk with the IP packet size smaller than the maximum IP packet size. Hence ${O_{ch}} = {S_h}$ and the gain ${g_{CT - CBR}}$ is given by
\begin{equation}
	\label{eqn:g_CT-2}
	\begin{array}{l}
		{g_{CT - CBR}} = \frac{{n({S_{cb}} + {O_{cb}})}}{B} + n{V_b} - (k + n - 1)(\frac{{{S_{ch}} + {O_{ch}}}}{B} + {V_{ch}})\\
		= \frac{{n({S_{cb}} + {O_{cb}}) - (k + n - 1)(\frac{{{S_{cb}}}}{k} + {S_h})}}{B} + n{V_b} - (k + n - 1)\frac{{{V_b}}}{k}
	\end{array}
\end{equation}
From (\ref{eqn:g_CT-2}), we can see that ${L_{CT - CBR}}$ is no more a decreasing function of $k$. To find the optimal k that maximizes the gain expressed in (\ref{eqn:g_CT-2}), we can set the derivative of  ${L_{CT - CBR}}$ with respect to $k$ to zero: $\frac{{d{g_{CT - CBR}}}}{{dk}} = 0$, and solve the equation. The optimal k is given by
\begin{equation}
	\label{eqn:choice_k}
	{k^*} = \sqrt {\frac{{B(n - 1)({V_b} + {S_{cb}})}}{{{S_h}}}}
\end{equation}
where the gain ${L_{CT - CBR}}$ achieves its maximum.

The above analysis for a linear network shows the potential gain brought by our Cut-through CBR protocol. In the next section, we will investigate the performances of our Cut-through CBR and Coded Cut-through CBR protocols under a practical network setup.

\section{Simulation Results}
\label{section:simulation}
This section presents simulation results comparing the performance of the four block-propagation protocols: SR, CBR, Cut-through CBR, and Coded Cut-through CBR. Specifically, using the network simulator 3 (NS3) \cite{henderson2008network}, we investigate the block-propagation latencies of these four propagation protocols in a simulated Bitcoin network.

\subsection{Simulation Setup}
Our investigation is performed on a simulator extended from the Bitcoin simulator implemented by \cite{gervais2016security}. The Bitcoin simulator, written in NS3, is designed to simulate Bitcoin nodes' behavior in the Bitcoin network. The Bitcoin simulator can simulate a Bitcoin network with thousands of nodes. The Bitcoin simulator retrieved the current geographical node distribution from bitnodes.21.co and adopted the distribution to define its simulated nodes' locations. In the simulated Bitcoin network, the connection between two nodes is established as a point-to-point (P2P) link. Each P2P link has a random bandwidth and transmission delay (according to the geographical location) following a statistical distribution from Verizon \cite{verizon} and testmy.net \cite{testmy}. The parameters in Table I presents the parameters used in the Bitcoin simulator \cite{gervais2016security}.

\begin{table}[]
	\caption{PARAMETERS OF THE BITCOIN SIMULATOR}
	\label{tab:my-table}
	\centering
	\begin{tabular}{|l|l|}
		\hline
		Parameter                   & Bitcoin Simulator                                                                           \\ \hline
		\# of the nodes             & 6000                                                                                \\ \hline
		Block interval              & 10 min                                                                                \\ \hline
		\# of the connection        & \begin{tabular}[c]{@{}l@{}}Distribution according to\\ Miller et al. \cite{miller2015discovering}\end{tabular} \\ \hline
		Geographical distribution   & \begin{tabular}[c]{@{}l@{}}Distribution according to \\ actual blockchains\end{tabular}     \\ \hline
		Bandwidth propagation delay & \begin{tabular}[c]{@{}l@{}}6 regional bandwidth and \\propagation delay\end{tabular}        \\ \hline
	\end{tabular}
\end{table}
The original Bitcoin simulator already included the SR protocol. We implemented CBR, Cut-through CBR and Coded Cut-through CBR in the simulator. The extended simulator allows us to set parameters such as the block size and the chunks per block for Cut-through CBR and Coded Cut-through CBR. We performed simulations to investigate the effect of block size on the network block propagation latency and the propagation divergence factor defined in (\ref{eqn:PDF}) under different block propagation protocols. Our overall simulation experiment consists of several simulation runs. We fixed a block size for each run and then ran separate simulations to evaluate SR, CBR, Cut-through CBR, and Coded Cut-through CBR. Each simulation run, for a specific relay protocol, monitored the statistics of up to $10\,000$ blocks created during the simulation to smooth the experimental results.

\begin{figure}[!t]
	\centering
	\includegraphics[width=3.5in]{Figure5.png}

	\caption{Median block propagation latency versus block size for different block propagation protocols.}
	\label{fig_5}
\end{figure}

\begin{figure}
	\begin{subfigure}{.5\textwidth}
		\centering

		\includegraphics[width=.8\linewidth]{Figure-CDF1M.png}
		\caption{BLOCK SIZE: 1 MB}

	\end{subfigure}
	\begin{subfigure}{.5\textwidth}
		\centering

		\includegraphics[width=.8\linewidth]{Figure-CDF25M.png} \caption{BLOCK SIZE: 25 MB}
	\end{subfigure}

	\begin{subfigure}{.5\textwidth}
		\centering

		\includegraphics[width=.8\linewidth]{Figure-CDF50M.png} \caption{BLOCK SIZE: 50 MB}

	\end{subfigure}

	\begin{subfigure}{.5\textwidth}
		\centering

		\includegraphics[width=.8\linewidth]{Figure-CDF100M.png}\caption{BLOCK SIZE: 100 MB}
	\end{subfigure}
	\caption{CDF of block propagation latency for different block propagation protocols.}
	\label{fig_6}
\end{figure}

\subsection{Experimental Results}
Fig. \ref{fig_5} and Fig. \ref{fig_6} show the median and the CDF of the block propagation latency, respectively. We have the following observations:
\begin{enumerate}
	\item When relaying a large block, cut-through forwarding can significantly speed up block propagation with respect to SR and CBR. For example, Fig. 5 and Fig. 6 show that when relaying a block larger than $25$ MB, Cut-through CBR and Coded Cut-through CBR reduce both the median and the tail of block propagation latency by up to three times compared with CBR and by up to more than one hundred times compared with SR.
	\item Coded Cut-thought CBR can further speed up the block propagation compared to Cut-through CBR. For example, Fig. 5 and Fig. 6 show that the median and the tail of block propagation latency of Coded Cut-through CBR are both up to two times smaller than that of cut-through CBR for different $k$.
\end{enumerate}

Fig. \ref{fig_7} shows the stale-block rate versus the propagation divergence factor $\Delta $. We can see that large $\Delta $ increases stale-block rate significantly. The reason is that when the block propagation divergence factor is large, a miner cannot receive the latest announced block (mined by others) in time and may still announce its mined block with the same block height, leading to a large stale-block rate. Fig. 8 shows the propagation divergence factor $\Delta $ of different protocols when different block sizes are used. From Fig. \ref{fig_8}, we can see that the propagation divergence factors $\Delta $ of SR and CBR increase significantly when the block size is large, leading to a large stale-block rate. For example, increasing block size from 1 MB to 100 MB (100x) increases the propagation divergence factor $\Delta $ by 30x and increases the stale-block rate by around 30x for CBR. However, Cut-through CBR and Coded Cut-through CBR can suppress the increase of $\Delta $ with the increase of block size. In particular, the $\Delta $ of Coded Cut-through CBR with the optimal $k$ (the optimal $k$ is obtained through experiments), when the block size is 100 MB, is roughly equal to the $\Delta $ of SR when the block size is 1MB.

\begin{figure}[!t]
	\centering
	\includegraphics[width=3.5in]{Figure7.png}

	\caption{Stale-block size versus propagation divergence factor derived using (\ref{eqn:forkCal}).}
	\label{fig_7}
\end{figure}

\begin{figure}[!t]
	\centering
	\includegraphics[width=3.5in]{Figure8.png}

	\caption{Propagation divergence factor versus block size for different block propagation protocols.}
	\label{fig_8}
\end{figure}

In summary, Cut-through CBR and Coded Cut-through CBR can be used for propagating 100 MB blocks while maintaining the propagation latency to the level of the traditional block propagation protocol that propagates 1 MB blocks, hence increasing the TPS capacity by 100x.

\section{Conclusion}
\label{section:conclusion}
We proposed a new blockchain networking protocol  to increase the TPS of the Bitcoin blockchain. When a large block size is used in the Bitcoin blockchain, original block propagation protocols, such as SR and CBR, suffer from large block propagation delays to large stale-block rate, compromising the blockchain's security. In this work, we put forth a two-pronged approach to increase the block size without inducing extra propagation latency. First, we design a Cut-through CBR that enables parallel reception and forwarding of compact blocks at relay nodes. Second, we design a Coded Cut-through CBR that incorporates rateless erasure codes into Cut-through CBR to further increase efficiency. Our simulation results demonstrate that our protocols can significantly reduce the block propagation latency and suppress the stale-block rate. Specifically, our protocols can increase the TPS of the Bitcoin blockchain by 100x without compromising the blockchain's security. More importantly, our approach only needs to rework the communication and networking architecture of the current Bitcoin blockchain without changing the data structures and crypto-functional components in them. Therefore, our protocols can be seamlessly incorporated into the existing Bitcoin blockchain. The implementation of our protocols in Bitcoin-like blockchains may allow the blockchains to be used in many use cases not possible currently.
\ifCLASSOPTIONcaptionsoff
  \newpage
\fi

\bibliographystyle{IEEEtran}


William Conrad Marshall Matt Dillon-Gunsmoke Various radio roles He was best known for playing Cannon in the television show of the same name.
Trivia for the famous, Oscar-nominated Irish actor Liam Neeson.
Frank Lovejoy was an American actor in radio, film, and television. He was born Frank Andrew Lovejoy Jr (Meet McGraw, I Was A Communist For the FBI.
But before his death from a heart attack in 1982, he had become frustrated that his kind of show no longer seemed sellable.
Victor Rodman was an American actor best known for his work on two Jack Webb NBC television programs, Dragnet and Noah's Ark.
Dragnet premiered on the radio on June 3, 1949, with Jack Webb as Joe Friday and Barton Yarborough as his partner Ben Romero.


Are you ready to quit? Opioid dependence is a challenging disease that often requires medication assisted therapy. One of the benefits of Suboxone is that the patient receives treatment right in our office by a trained addiction treatment physician registered with the Department of Health and Human Services and certified by the DEA.
What is an opioid? Opioids are addictive narcotics in the same family as opium and heroin. This includes prescription pain medications such as Codeine, Vicodin, Demerol, Dilaudid, Morphine, Oxycontin, Percodan, Methadone, and Suboxone.
Why are opioids used to treat addiction? Isn't this substituting one addiction for another? Suboxone blocks the opiate sites in the body and prevents any response to opiates taken. Even though maintenance treatment works very well, it is not a cure by itself. It is our goal to encourage the patient to learn to live independent of Suboxone. This takes patience, counseling, and time.
Am I a candidate for Suboxone treatment? Take the first step by calling our office today at 360-757-0027. Our treatment panel is limited to only pre-qualified patients who are serious about overcoming addiction. Let's determine if this program is a good match for you. Download the forms from this website. Fax your completed forms to 360-757-3698.


(Host) Congressman Peter Welch says he reluctantly voted in favor of latest financial industry bailout bill.
(Host) Welch says he believes something needed to be done to deal with the credit crisis.
He says he won't get everything he wants out of the bill. But Welch says one of the most important things to him was an accounting change that the Securities and Exchange Commission will adopt.
Welch says that will protect taxpayers.
Welch says he got personal assurances from Senator Barack Obama that a new Democratic administration would adopt more taxpayer protections.


Rolleston recently welcomed its first township traffic lights, but six more sets of lights are to be installed over the next decade around Lincoln and Rolleston.
Alongside the two sets of lights already installed in Rolleston, another two are scheduled as part of the Long-Term Plan, while four sets are set to be installed in Lincoln.
The two recently installed lights in Rolleston are on Rolleston Drive/Masefield Drive, and at Hoskyns Road/Jones Road.
The two new projects set to be completed over the next three years will see traffic lights replacing the roundabouts at Tennyson/Springston Rolleston/Lowes Road and at Rolleston Drive/Tennyson Street.
Asset Manager Transportation, Andrew Mazey, says the new Rolleston Drive/Tennyson Street lights are designed to work in with the town centre development.
"We would like to coordinate this work in with the construction of the marquee town centre build of the new community centre and library. For Mazey and his team, this work is about future-proofing a continually growing town.
The Council is also working alongside the NZ Transport Agency to help improve access to Rolleston.
Like Rolleston, Lincoln has also been experiencing significant growth, and a beautification process of Gerald Street will run alongside the installation of new traffic lights in the village.
Four sets of traffic lights are set to be installed at intersections along Gerald Street. They will be at Gerald/West Belt, Gerald/Veron Drive, Gerald/Springs Road and Gerald/James and Edward Street.
Andrew Mazey says these will be hugely important to help preserve the village feel of Lincoln.
Mr Mazey says the travel habits of Lincoln University students is aa factor in planning the new projects, and the Gerald Street/Springs Road traffic signals will help ensure the safety of those travelling to and from the University campus.


Decision making depends on the information available, and the available information depends on how the data is handled. The strength of XP3 is that the data acquisition and delivery process is kept simple for the users.
IT infrastructure, hardware and software requirements.


text:
Home>World>Shakira is afraid of Clara Chia Marty and her relationship with Gerard Pique
Shakira is afraid of Clara Chia Marty and her relationship with Gerard Pique
in recent months, Shakira has led a turbulent lifestyle, because after separating from Gerard Piqué Several situations have arisen that have changed their plans. what to do with something above reasons Those who have come to light and for whom the interpreter of "Monotonia" said that he has Fear of Clara Chia Martis And this Relationship Which he has with the Barcelona footballer.
and it has been since Gerard Piqué made his public Relationship Thief Clara Chia MartisThe woman from Barranquilla has had to live with the media focus behind her and her sons, it is well known that Shakira He is adamant on the idea of moving Sasha and Milan to Miami for their own good, so he has done everything in his power to make sure that custody is by his side so that he can move on with the kids as soon as possible. . possible.
in his last interview with allieThe record-breaking singer with 'Monotonia' with Ozuna and over 65 million views on YouTube after the premiere of the video, assures that the press's treatment of her has been too harsh and too aggressive sons,They don't deserve to be seen every second, photographed at school, or chased by paparazzi"; the reason for taking them away from Barcelona. However, in a recent publication in Hola!, new information appears and reasons for which he has Fear of Clara Chia MartisAnd that includes the health of Saha and Milan.
Shakira is afraid of Clara Chia Marty and because of her relationship with Pike
a chief apprehension who has faced Shakiraafter what Gerard Piqué You Clara Chia Martis they will scream Relationship For the four winds, all this news and headlines reach their ears sons, Since the football player and singer released their separation statement, they have made it clear that they will do whatever it takes to keep their little ones away from all media.
That is why, it is reported in the magazine that one of the reasons is that Shakira passed Fear Saha and Milan find out in their school Relationship what does your dad have Clara Chia Martis, with whom the children are known have already lived the time when Peake took them to Kosmos. That's why Colombians insist at all costs to take him sons a miami.
The thing that scares the artist the most is that the kids get to know all the news at school about the new relationship between the Barcelona player and Clara Chia Martis,
In accordance with the foregoing, in the previous meetings held Gerard Piqué AndWelcome regarding their custody sons, the culé took advantage thanks to the laws of Spain where he brought that Sasha and Milan would not be able to leave the country until they had completed their current course in school. Ever since it was announced, Fear Colombian is that he would have to wait two years to be able to move to Miami, which makes children more likely to live in that period. Clara Chia Martis,
Shakira Lately she is very focused on her professional career, so she always tries to be very cautious with everything she does, so as not to affect the friendly and momentary agreement with him. Gerard Piqué for their custody sons, The above pertains to his musical releases, which is why many media are thinking "Who takes care of them?,
It should be remembered that since their separation Shakira You Gerard Piqué He announced that he would not announce that they had a relationship until some time passed, but he did not follow through as not even three months had passed since he had decided to go out in public. Clara Chia Martis, However, the 23-year-old has definitely decided not to appear in front of the cameras. reasons Like the premiere of "Monotonia" and the health status of Barranquilla's father, William Mebarak, which is feared, is still fragile.
Clara Chia Martis Gerard Pick Shakira sons

redpajama_set_name: RedPajamaCommonCrawl


text:
Grand Théâtre, finalist for the WAN Awards 2021: its glass façade honoured.
The protective envelope designed for the Grand Théâtre de Québec was named finalist at the WAN Awards 2021 in the categories of Materials - Glass, and Architecture - Façade.
The new protective structure of this iconic building, designed by Victor Prus, breathes new life into the original concrete building by delicately encasing it in a glass envelope. Sometimes immaterial, sometimes reflective, the glass case presents itself as a new work of art, in dialogue with its audience and the urban landscape.
"The Grand Théâtre de Québec is still on display within the city today, that is to say, one can admire it in the evening thanks to its transparent façade. But what is truly interesting is that it is also a reflection of us. And there, it's the dialogue between art and the individual, art and the community."
It was the team's exemplary synergy between the collaborators that ensured the success of this major and unique technical challenge.
Let Eric Pelletier share with you the thinking and explorations behind the design of the Grand Théâtre de Québec renovation project: watch episode 2 of Sketching Stories.
Designing our way into better client relationships
Navigating the New Normal: design as a form of activism


You've heard the usual mantra: soda water and salt crackers. And if you've tried it, you already know…that's a prescription for disaster! Salt is fine….but the carbonation can irritate your stomach lining, and those white flour crackers provide zero nutritional benefit. You get a brief respite from misery as your blood sugar level spikes…..and then it drops to worse than it was before.
Good nutrition is the mantra here at BlueRibbonBaby.org! And it works on morning sickness, too. The trick is to eat BEFORE you get sick.
Your baby may not require a lot of calories in the early weeks to grow, but your placenta does. Morning sickness occurs because your body is busy trying to keep everything in balance while growing a placenta and you need a constant supply of nutrients to accomplish this. If you get behind on your nutrition, your blood sugar level drops rapidly, leaving you at the mercy of your raging hormones and feeling nauseated, dizzy and miserable.
The "vicious cycle" of morning sickness is typical: You might not even get around to feeling hungry before you start to feel sick, and once you feel sick you certainly don't feel like eating, so you don't….and then you feel worse and worse until the inevitable happens.
As you well know, the idea of food is not very enticing once you're feeling queasy! But morning sickness is not the flu! The reasons for feeling sick are entirely different, and the reasons for vomiting are entirely different. You CAN eat when you're pregnant, you can't eat when you have the flu. So the key is to stay ahead of your body, by eating good, protein-rich foods regularly, in snack-size quantities, before nausea sets in. If you start to feel the least bit queasy….EAT!
Dr. Brewer recommended that pregnant women forget the traditional three meals day, and adopt a "grazing" meal schedule instead. In the later months of pregnancy, there just isn't room in your belly for a big dinner AND a baby…but in the early months, you need to eat constantly to keep your blood sugar levels stable, and stave off nausea. You can still have three meals with your family when you eat a little more than just a snack, but don't limit yourself to only three meals. Once a meal "wears off" you'll start to feel queasy, and that's when the vicious cycle of morning sickness sets in.
I personally tried this approach with my second pregnancy. In my first pregnancy, I had the typical morning sickness struggles. It completely disrupted my life, my work schedule, and any thought of enjoying pregnancy! I lived in fear of not making it to the bathroom in time, and I kept zip-lock baggies in my glove box and my purse "just in case". I had no clue about good nutrition in the early months of my first pregnancy — all I had to go on was the "Best Odds Diet" and it wasn't working for me. I experienced intermittent nausea and vomiting all throughout that pregnancy, and I never realized that I might have been able to do something about it.
By the time I was pregnant with my second, I had met Dr. Brewer and my entire world was changed! Pregnancy was a joy, I felt healthy, and I hardly had a trace of nausea. I had started eating right from the minute the line turned blue, and I breezed through the first trimester with only an occasional twinge of nausea — which I combated by EATING IMMEDIATELY! The tiniest hint of discomfort was my cue to eat, and it worked wonders.
I have since taught this concept to my childbirth students and any expectant moms I meet, and invariably the response has been the same: Wow!! What a difference!
Give it a try….you've got nothing to lose, and everything to gain!
I had a bit of morning sickness with my first child. We weren't very well off then, and we resorted to canned foods, rice, and hardly any fruits or veggies to be able to make our rent payments. With this pregnancy, I was able to follow the Brewer diet, and I have felt great… except when we visited my in-laws who only eat from a box. I felt absolutely miserable for the three weeks we stayed with them. It was amazing how great my body felt to how sickly I felt by eating processed foods! I continue to follow the Brewer diet because it is the essence of nutrition for pregnancy. I have never felt better. I love being pregnant.
I have had Hyperemesis Gravidarum with all my pregnancies (working on #4 right now) and am lucky enough to have found a drug combination that works just enough that I don't throw up. However, the constant nausea is terrible, I have no appetite at all and each bite requires effort to swallow. Yet I am committed to consume the Brewer Diet every day and am finding that they are the very foods I crave: potatoes, cheese, spinach, tomatoes, whole grain toast with peanut butter, etc. I know many women aren't as lucky and have to do with whatever will stay down, but I encourage everyone to try to keep to this diet. I have given birth to three perfect children with no complications by following this diet and highly recommend it!


text:
és un corredor japonés de llarga distància especialitzat en maratons.

Marques

Millors marques personals
 5.000 metres - 13:39.38 min (2002)
 10.000 metres - 28:13.76 min (2000)
 Mitja Marató - 1:01:54 h. (2002)
 Marató - 2:07:52 h. (2001)

Enllaços externs

 sports-reference
 marathoninfo

Atletes japonesos
Maratonians asiàtics
Persones de la Prefectura de Yamaguchi
Esportistes japonesos als Jocs Olímpics d'estiu de 2004
Atletes asiàtics

redpajama_set_name: RedPajamaWikipedia


text:
Identify and discuss two specific disparities for the racial or ethnic group under consideration.
Your readings to this point have documented significant differences—disparities—in health care provided for different racial and ethnic groups. This assignment provides an opportunity to reflect on, analyze, and write about group differences and health disparities.
Textbook authors Pérez and Luquis (p. 24) suggest, "[t]he reasons why we observe these disparities are not clearly understood and may be due to other factors as individual choices, differences in disease processes, or systemic barriers to care, or to any combination of these factors."
Given that thinking, imagine that you have been asked by the regional director of health care services to select and evaluate ethnic group diseases and illnesses, disparities, behaviors, and probable causes.
Your research-based assignment is to identify and discuss health care disparities and wellness issues for a particular cultural group:
Select a population for which there is evidence of health care disparities. For this population:
Identify and describe two diseases with high incidence for the cultural (ethnic or racial) group.
Describe how the group is being affected.
What strategies are currently being employed or considered to increase wellness?
What additional considerations do you think might be useful?
Identify and discuss two specific disparities for the racial or ethnic group under consideration. Provide specific examples, and identify salient factors (such as socioeconomic status).
Identify and evaluate the group's beliefs, values, and traditions related to quality health, disparities, and wellness.
Based on analysis of your cultural group, formulate assumptions (hypotheses) about locus of control (internal versus external) in a specific cultural group's health, wellness, and disease. The research must focus on your selected cultural group.
Reflect on what you have found. Provide any insights, conclusions, or recommendations that you have arrived at from your research and analysis.
The following are assignment requirements for creating your research-based paper:
The paper must follow APA Citing and Referencing Guidelines, which appear in the Capella Undergraduate Online Writing Center. You will need a cover page, a table of contents, body of the paper, and a reference page.
Length: the paper should be at least five to seven double-spaced pages excluding cover page, table of contents, and reference page.
References: list all references used. At a minimum, you are required to identify and use at least three sources in addition to your textbooks. Additional relevant references from the Capella University library are always welcome and encouraged.
Review the Cultural Health Disparities Research-Based Paper Scoring Guide to see how you will be graded on this assignment.
Submit your Cultural Health Disparities Research-Based Paper in the assignment area by Friday of this week.
Pérez, M. A., Luquis, R. R. (2008). Cultural competence in health education and health promotion. San Francisco, CA: Jossey-Bass.


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Royal #BDS | Jordan's King Abdullah II refuses to meet Netanyahu
Thursday, 28 July 2011 14:20| MEMO
According to reports by a Kuwaiti daily made on Wednesday, July 27, King Abdullah II of Jordan recently declined a secret meeting with Israeli Prime Minister, Binyamin Netanyahu.
'Well informed' anonymous sources told Al-Jareeda newspaper that Netanyahu had sent a special emissary to Amman to request a secret meeting with Abdullah in Aqaba. However, the King refused saying that his schedule was overloaded.
According to the paper, Jordan's King is "angry with the Israeli Prime Minister over his government's position on Israeli-Palestinian negotiations; over statements made by figures close to Netanyahu asserting that 'Jordan is Palestine'; and over Netanyahu's position on the Jordan Valley and his insistence that it remains under Israeli sovereignty."
During a meeting with a delegation of Kuwaiti journalists on Tuesday, King Abdullah asserted that he was not optimistic about the future of the settlement process in the region. He expressed a lack of trust in the Israeli government and his particular worry that Jordan's gates could be forced wide open to Arab newcomers whose countries are witnessing political change.
BDS, Israel, israeli, Palestine, palestinians, Politics
bibi, israel, israeli, Jordan, Jordanian, King Abdullah, meet, netanyahu, refuses
Israeli police detain 150 Palestinian workers
Five arrested, child and foreigner assaulted in West Bank attacks


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Stratham è un comune degli Stati Uniti d'America facente parte della contea di Rockingham nello stato del New Hampshire.

Note

Altri progetti

Collegamenti esterni


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Nibiru: Age of Secrets demo released
Game's hero Martin Holan needs entry to a mysterious tunnel in adventure game's first level, now on GameSpot DLX.
By Benjamin Golze on August 19, 2005 at 11:12AM PDT
The Adventure Company has released a demo for its upcoming adventure game Nibiru: Age of Secrets. The demo, now available on GameSpot DLX, puts players up against one of the first dilemmas in the game, where hero Martin Holan is blocked entry to a recently unearthed World War II-era tunnel.
Nibiru's storyline kicks off from that point, and Holan, a linguistics and archaeology student, eventually finds himself enwrapped in a mystery involving Nazis, Mayans, and extraterrestrials. The full game will feature 20 to 30 hours of gameplay over 80 different locations.
NIbiru: Age of Secrets is rated T for Teen and will be released for the PC in September for $19.99. For more, take a look at our E3 impressions.
Nibiru: Age of Secrets
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The holiday boss almost cracked a smile !
OMG, I love, love, love these. Please, write a pattern for them.
Delicious, even the worm. What a treat!
So sorry! Not a worm but a twig!
The holiday boss is a hardarse and should be given a stern talking-to, with lots of finger-wagging, Jodie!
Oh Jodie you have out done yourself they are just toooooooo cute. Cannot wait to make some of these.
just when I think you can't get any more awesome, you get more awesome.
that is so cute/adorable/fantastic/I'verunoutofadjectives that I can't stand it.
So cute. Glad you made it to the end of all those french knots!
That little bird would make a great 'stick pin' brooch to fly from room to room keeping an eye on things for me.
Can't wait for the release of these patterns!


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Full Council Deputation
The following is one of the 3 Deputations made for Hayling Island, and requesting that the Housing Statement to 2036 be referred back for a thorough - and long overdue - infrastructure review. Each of the 8 Deputees speaking for 4 principal sections of the Borough's Housing Statement had no more than 4 minutes in which to make their points, so of necessity, detail and breadth were limited. However I gave to the Press a copy of my Deputation plus the several pages of supporting References which are available should you wish to see them.
"What legacy are we leaving our future generations? That decision is in your hands this evening.
Do we want to live in ribbon development? To travel in gridlock and destroy irreplaceable fields?
Havant's Housing Statement to 2036 is based on the Plan for Urban South Hampshire that is non-statutory, and the National Planning Policy Framework, that is supposedly to promote healthy communities, conserve and enhance natural and historic environments and meet the challenge of flooding and coastal change.
Let's consider Hayling Island, 4 by 4 miles at its widest, half a mile wide at its centre.
Substantial eastern, north, central, southwestern sections are listed as Flood Zone 3: that means high probability OR functional floodplains where water has to be allowed to flow. Many Hayling residents – even now - get night time texts warning them to be prepared for imminent flooding & to go to higher ground – on Hayling?
Claim is made that the Housing Statement is sustainable. What exactly does that mean? Any Council Plan must, the NPPF states, 'plan for biodiversity',"include international, national … locally designated sites of importance for … wildlife corridors" and if there cannot be mitigation or compensation, then planning permission should be refused.
Please remember that Hayling Island lies between the internationally important Special Protection Areas of Langstone and Chichester Harbours. The currently deferred housing site, UE18, is a designated Site of Importance for Nature Conservation, routinely floods, already acts as flood mitigation for surrounding homes. The Rook Farm fields UE77 do have recognized Brent Geese occupation (300 recorded at a time) and Natural England have just notified the Council. These are Grade 2, versatile Agricultural land. This would be a major irreplaceable loss of higher quality land.
How can it be sustainable to excavate, mitigate flooding by building on 'flood mitigation' zones and migratory bird sites? Where will the flood and surface water go? Sea levels are forecast to rise and there are no flood defences planned for Hayling's steadily eroding west coast, approximately one eighth of a mile from the proposed housing.
Even in a 1980s modern-built, housing estate on Hayling, some have routinely suffered from toilets backing up during high surface water, and Southern Water has been unable to stop this.
What about the promised cheaper property for our young people? I heard our Housing Officers clearly state, on October 19th this year, that Havant Borough Council could not force developers to provide the Council's minimum of 30% Affordable Housing. Nor can they force developers to improve the crumbling Billy Trail.
Hayling is renowned not only for bird watching but also as a world class, safe, watersports and Blue Flag beach, 'rural' destination. 30,000 vehicles in August 2016 stopped traffic for 3 hours on Hayling's A3023. More houses and their cars destroy not only our habitats but Havant's valuable tourist economy.
Finally, what will you say to families whose loved ones could not be driven to A&E in time because of predictable gridlock congestion on the A3023 single road on & off our Island?
Please think about the legacy you leave behind. Please refer the Statement back for a thorough infrastructure review.
Thank you. "


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What Is a Gazebo Used For?
Outdoor Room Basics
By Lisa Hallett Taylor
Cathleen Abers-Kimball / Getty Images
A gazebo is a freestanding, open garden structure, sometimes hexagonal or octagonal in shape, with a roof. Most gazebos are constructed of wood or metal and have built-in seating inside the sheltered area. To add a sense of enclosure and privacy, latticework or outdoor curtains or drapes are sometimes used. In a garden setting, a gazebo can serve as a focal point—something to be viewed and appreciated—or situated in a location on a property (like a hill) that offers views while providing shelter from the sun.
Depending on the region or culture, a gazebo might also be referred to as an alhambra, belvedere, kiosk, pagoda, pavilion, pergola, rotunda, shed, summerhouse, or tea house.
Adding a gazebo to your outdoor space should be carefully thought out because it can often look contrived and awkward or out of place. When planning any garden structure, try to incorporate architectural elements or features of your house for harmony and continuity. Also be aware of design considerations such as:
Scale and proportion: Does the size and shape of the proposed gazebo fit in your yard so that it's neither too big or too small for the location?
Style: Does it blend with your house and other structures on the property?
Materials: Are materials like stone, wood, and iron used elsewhere on the exterior of your house?
Location: A gazebo might be a destination, an escape, or be a place that frames a beautiful view.
Additional hardscape features, like paths or walls: Do the materials and shapes echo those used in other parts of the yard or exterior of the home?
Small cities in the late 19th and early 20th centuries often had large gazebos in the town center or park, where they often served as bandstands. Because they have a nostalgic appeal, gazebos are a popular prop for garden weddings and are often associated with romantic scenes in films like The Sound of Music and for photographs.
The real gazebo on "The Sound of Music" set in Austria was too small for the "Sixteen Going on Seventeen" dance sequence, so the scene was filmed in a replica gazebo on a sound stage in California.
Gazebo-like structures have been built for centuries. The Egyptians built garden gazebos to support grapes for wine and raisins. They believed that these earthly paradises—gazebos and gardens—would follow them to heaven.
Greece and Rome
Gazebos can be traced back to ancient Greece and Rome. The Greeks built temples in public spaces that were surrounded by gardens, with marble gazebos in memory of gods and goddesses.
The Romans enjoyed their private gardens as places to relax and entertain. Garden gazebos were constructed as a beautiful outdoor feature and as a gathering place.
Medieval and Renaissance Periods
While gazebos do attract attention, they also were, and still are, built to offer privacy. Elaborate gardens at churches and monasteries used gazebos as places for meditation or to establish a shrine. In Medieval and Renaissance Europe, these sanctuaries were built in more far-off areas of large estates. A gazebo would serve as a destination to which the lord of the manor and his guests would journey outside for fresh air while still under a roof.
Garden gazebos became popular in England during the 16th through 18th centuries and could be found in parks or large private estates. In the 19th century, gazebos were built for middle-class properties and also became more functional as a shelter rather than a decorative architectural feature in the landscape. The English practice of afternoon tea was enjoyed in gazebos or similar structures.
Tea houses—or teahouses—are another form of a gazebo that has been popular in China and Japan for centuries. Tea ceremonies are a time of rest, meditation, and reflection while enjoying one another's company and admiring the beautiful surroundings of nature
Creating a Private Place
With residential properties decreasing in size, it's hard to find a place to create a refuge—somewhere to get away from the cares of the day or your household. To establish a cozy hideaway on a smaller lot, add a pergola or overhead roof to your gazebo, paving, and a path leading to the area. For added privacy, create walls with lattice panels on the sides, and plant vines to grow up and over the framework. It will be beautiful to look at and a nice escape on your own property.
What is an Arbor Used For?
What Is an Accessory Building?
What Is the Difference Between a Pergola and an Arbor?
What's the Difference Between a Baluster and Balustrade?
27 Gorgeous Gazebo Design Ideas
What Is a Pergola?
What is Tuscan Landscaping?
Top Wooden Structures for Lawns and Gardens
25 Perfect Pergola Designs for Your Garden
What is a Courtyard or Atrium as Part of a House?
What Is a Cabana and How Is It Used?
English Cottages That Will Make You Leave the City
Get Inspired: 20 Stylish Shed Designs
Small Garden Ideas and Inspiration
50 Outdoor Dream Kitchens for Every Style and Space
11 Free Gazebo Plans


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The Grain Brain Cookbook: More Than 150 Life-Changing Gluten-Free Recipes to Transform Your Health (Hardcover)
By David Perlmutter, MD
The authorized companion to the #1 New York Times bestseller Grain Brain, with more than 150 life-changing gluten-free recipes for complete health and vitality.
Dr. David Perlmutter's groundbreaking bestseller Grain Brain revolutionized the way we think about our health, exposing the devastating effects of wheat, sugar, and carbs on the brain. By eating the right foods, you can profoundly affect how your brain will be working next year, in five years, and for the rest of your life.
The Grain Brain Cookbook presents more than 150 delectable recipes to keep your brain vibrant and your body fit, all while dramatically reducing your risk for — and treating — Alzheimer's, depression, ADHD, and epilepsy, as well as relieving everyday conditions like headaches, insomnia, and forgetfulness. With delicious recipes for every meal — including Spicy Chicken Burgers with Guacamole, Gruyere-Glazed Pork Chops and Cauliflower "Couscous," and many more — The Grain Brain Cookbook gives you all the tools you need to build a gluten-free diet full of wholesome, flavorful, easy-to-make meals.
What you eat is the most important decision you make every day in terms of your health, and once you've tasted how good the Grain Brain diet can be, you'll want to keep making the right choices day after day.
David Perlmutter, MD, is a board-certified neurologist and a Fellow of the American College of Nutrition. He was the recipient of the Linus Pauling Award for his innovative approaches to neurological disorders. With his books now published in twenty-seven languages, Dr. Perlmutter is setting new standards for what healthy lifestyle means around the world.
He is the author of the New York Times bestsellers Grain Brain, The Grain Brain Cookbook, and Brain Maker, as well as The Better Brain Book and Raise a Smarter Child by Kindergarten. He lives in Naples, Florida.
Cooking / Health & Healing / Weight Control
Cooking / Health & Healing / Gluten-Free
Cooking / Health & Healing / Low Carbohydrate
A persuasive case for the wheat-free approach to preserve brain health and functioning."- William Davis, MD, author of Wheat Belly
"Mind-blowing and disruptive to some long-standing beliefs about what our bodies require for optimal health...Grain Brain lays out an easy-to-understand roadmap packed with the latest science."-Psychology Today
"A tour de force that is destined to save many lives. Please read it."-Health Central
"A galvanizing call to arms."-Kirkus Reviews


2018 Ford F-150 Salt Lake City, Murray, South Jordan, West Valley City, West Jordan, UT 50037 - Guangdong Kamtat Lighting Technology Joint Stock Co., Ltd.
Salt Lake City UT 84115This 2018 Ford F-150 Lariat 4WD SuperCrew 5.5′ Box is proudly offered by LHM Super Ford SFOThis Ford includes:* LARIAT SPORT APPEARANCE PACKAGE  * Aluminum Wheels  * Running Boards/Side Steps* ELECTRONIC LOCKING  * Locking/Limited Slip Differential* SHADOW BLACK* SYNC CONNECT  * Smart Device Integration* MAX TRAILER TOW PACKAGE  * Locking/Limited Slip Differential* TWIN PANEL MOONROOF  * Generic Sun/Moonroof  * Sun/Moonroof  * Dual Moonroof* VOICE-ACTIVATED TOUCHSCREEN NAVIGATION SYSTEM  * Navigation System* TRANSMISSION: ELECTRONIC 10-SPEED AUTOMATIC  * Transmission w/Dual Shift Mode  * A/T  * 10-Speed A/T* EQUIPMENT GROUP 501A MID  * Remote Engine Start  * Integrated Turn Signal Mirrors  * Power Mirror(s)  * Rear Parking Aid  * Universal Garage Door Opener  * Heated Mirrors  * Blind Spot Monitor  * Power Folding Mirrors  * Cross-Traffic Alert* FRONT LICENSE PLATE BRACKET* ENGINE: 3.5L V6 ECOBOOST  * V6 Cylinder Engine  * Gasoline Fuel  * Turbocharged* ALL-WEATHER RUBBER FLOOR MATS  * Floor Mats* TAILGATE STEP W/TAILGATE LIFT ASSIST*Note – For third party subscriptions or services, please contact the dealer for more information.*Pull up in the vehicle and the valet will want to parked on the front row. This Ford F-150 is the vehicle others dream to own. Don't miss your chance to make it your new ride. This vehicle comes with 4WD for better traction on unstable surfaces, like snow and dirt to give you the edge over anything you might encounter on the road.Where do you need to go today? Just punch it into the Ford F-150 on-board navigation system and hit the road.


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Lecture on colonial knowledge formation under British rule and modern Sri Lankan historiography
A lecture on the topic "Colonial knowledge formation under British rule and modern Sri Lankan historiography" will be held on October 29 by the National Trust Sri Lanka. The lecture will be conducted by Professor Gamini Keerawella, Ph.D.
A former senior professor in modern history at the University of Peradeniya, Professor Gamini Keerawella also served as a visiting senior research fellow at the University of Western Australia. Professor Keerawella's areas of research include historiography under British Rule in Sri Lanka, peace and security in the Indian ocean, identity politics and post-colonial state formation in Sri Lanka. The professor has authored over 50 research publications.
The National Trust for Cultural and Natural Heritage is a national non profit association instituted to protect and raise public awareness of the tangible and intangible heritage of the island which is n protected by any institution of the Government.
The trust conducts monthly lectures on the last Thursday of each month. The lectures are open to the members and the public free of charge. This lecture is the trust's 129th session of their monthly lecture series. The HNB Sustainability Foundation is the principal sponsor of the event.
The lecture will be held on October 29 from 6:30pm – 8:00 pm. Interested persons may register at https://forms.gle/Fesv6nVk39itPm7Q9 for further updates.
Photograph: yamu.lk


Buy International History of the Twentieth Century and Beyond 2 by Antony Best (ISBN: 9780415438964) from Amazon's Book Store. Everyday low prices and free delivery on eligible orders. Everyday low prices and free delivery on eligible orders.... Buy International History of the Twentieth Century and Beyond 2 by Antony Best (ISBN: 9780415438964) from Amazon's Book Store. Everyday low prices and free delivery on eligible orders. Everyday low prices and free delivery on eligible orders.
The Twentieth Century and Beyond: A Global. and developments in the twentieth century and beyond. of The Twentieth Century: Readings in Global History. Buy The Twentieth Century And Beyond: A Brief Global History at Walmart. This seventh edition incorporates the latest scholarship on twentieth century history.
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Download international history of the twentieth century and beyond or read online here in PDF or EPUB. Please click button to get international history of the twentieth century and beyond book now. All books are in clear copy here, and all files are secure so don't worry about it.


Widely-celebrated author Sinan Antoon's fourth and most sophisticated novel follows Nameer, a young Iraqi scholar earning his doctorate at Harvard, who is hired by filmmakers to help document the devastation of the 2003 invasion of Iraq. During the excursion, Nameer ventures to al-Mutanabbi street in Baghdad, famed for its bookshops, and encounters Wadood, an eccentric bookseller who is trying to catalogue everything destroyed by war, from objects, buildings, books and manuscripts, flora and fauna, to humans.
Entrusted with the catalogue and obsessed with Wadood's project, Nameer finds life in New York movingly intertwined with fragments from his homeland's past and its present--destroyed letters, verses, epigraphs, and anecdotes--in this stylistically ambitious panorama of the wreckage of war and the power of memory.


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package org.javifact.buildsrc;

import java.util.Collection;
import java.util.Set;

import com.google.common.collect.ImmutableSet;

/**
 * Created by neil on 30/12/14.
 */
public class GeneralUtils {

    private final static Set<Character> VOWLES = ImmutableSet.of('a', 'e', 'i', 'o', 'u', 'A', 'E', 'I', 'O', 'U');

    public static String ordinal(int i) {
        String[] sufixes = new String[] { "th", "st", "nd", "rd", "th", "th", "th", "th", "th", "th" };
        switch (i % 100) {
            case 11:
            case 12:
            case 13:
                return i + "th";
            default:
                return i + sufixes[i % 10];

        }
    }

    public static boolean isVowel(char c) {
        return VOWLES.contains(c);
    }

    public static <T> boolean allEqual(Collection<T> collection) {
        T firstElement = null;
        for (T element : collection) {
            if (firstElement == null) {
                firstElement = element;
            } else if (!firstElement.equals(element)){
                return false;
            }
        }

        return true;
    }

    /*public static void deleteRecursivelyIfExists(Path directory) {
        if (Files.exists(directory)) {
            if (Files.isDirectory(directory)) {

            }
        }
    }*/

}

redpajama_set_name: RedPajamaGithub


text:
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News 2019/10/24 Notice
Bit-kun, the mascot character of NII, visits NII Shonan Meeting
NII Shonan Meeting is a series of seminars for informatics and brings together world-leading researchers around the world to intensively debate on research topics in informatics in the training-camp-style. Up until now more than 100 meetings have been held with around 3200 participants.
Bit-kun as the trainee dog of NII Publicity will introduce the day of NII Shonan Meeting to you.
Now I am getting on a bus to NII Shonan Meeting. The nearest train stations to Shonan Village Center are three stations, JR Zushi, Keikyu Shin-zushi, and Shioiri stations.
I have just arrived at Shonan Village Center, the venue for Shonan Meeting!
I have found a signboard of NII Shonan Meeting at the entrance! I am very excited and looking forward to encountering what kind of researcher I can meet.
Organizers as the center at NII Shonan Meeting and many researchers come from all over the world, right now 58 countries. I am very excited about the research stories of all the participants.
Sometimes it has a group workshop style with the heated discussion like this photo. Everyone looks proactive.
Everyone looks enjoyable during the coffee break, too.
Although their living countries are far away one another, they are sharing the common research areas of informatics with one another based on a kindred spirit. They seem to have lots of endless talks.
Now it is the time for a group photo session in the interval of the seminar.
I have found group photos and message boards of the past Shonan meetings at the special corner near the seminar rooms.
I could see Mt. Fuji from the hill when I went outside in the evening! We can enjoy beautiful sea and clear sky from Shonan Village Center.
They had a cheerful party all together at the Welcome Banquet on the first night. They really got lively.
I have enjoyed the Shonan Meeting so much today. Then I need a good sleep for tomorrow. Good night! See you then.
NII Shonan Meeting Memorial Lecture
NII Shonan Meeting https://shonan.nii.ac.jp/
NII Shonan Meeting
2019/12/13 Recruitment 2019/12/06 News Release 2019/11/29 Award 2019/11/18 News Release 2019/11/12 Award 2019/10/30 Award 2019/10/30 Award 2019/10/24 Information 2019/10/09 Information 2019/10/02 Award 2019/10/01 News Release 2019/09/22 Award 2019/09/22 Award 2019/09/02 Information 2019/08/28 Award 2019/08/09 Information 2019/07/12 Information 2019/07/11 Award 2019/07/10 News Release 2019/06/26 Information 2019/06/21 Award 2019/06/20 Award 2019/05/09 Award 2019/05/06 Award 2019/04/26 News Release 2019/04/25 Information 2019/04/12 Information 2019/04/10 Award
2019/03/15 News Release 2019/03/01 News Release 2018/12/25 News Release 2018/12/13 Award 2018/12/13 Award 2018/12/11 News Release 2018/12/04 News Release 2018/11/14 Award 2018/11/14 Award 2018/11/14 Award 2018/11/06 News Release 2018/10/17 News Release 2018/09/20 Information 2018/09/20 Information 2018/07/24 Award 2018/07/16 Award 2018/07/03 Award 2018/06/29 Information 2018/05/20 Award 2018/05/16 News Release 2018/04/17 Information 2018/04/17 Information 2018/04/09 Award
2018/01/23 News Release 2018/01/18 News Release 2017/12/25 News Release 2017/12/14 News Release 2017/12/06 Award 2017/11/22 Award 2017/11/20 News Release 2017/10/26 News Release 2017/10/26 Award 2017/10/17 Award 2017/10/11 Award 2017/09/19 Award 2017/09/18 Award 2017/09/12 News Release 2017/09/04 Information 2017/08/20 Award 2017/08/09 News Release 2017/08/02 Award 2017/07/26 Award 2017/07/11 Award 2017/07/08 Award 2017/07/05 Award 2017/06/30 Information 2017/06/08 Award 2017/06/01 News Release 2017/05/16 Award 2017/04/05 Information
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2016/03/18 Information 2016/01/21 Information 2015/12/09 Award 2015/11/20 Award 2015/11/11 Information 2015/11/06 Award 2015/10/28 Award 2015/10/27 Award 2015/10/21 Award 2015/10/01 Award 2015/09/10 Information 2015/09/09 Award 2015/07/29 Information 2015/07/28 Award 2015/07/12 Award 2015/07/02 Information 2015/06/23 Award 2015/05/13 Information 2015/04/24 Award 2015/04/21 Information 2015/04/02 Information
2015/02/04 Award 2015/02/02 Award 2014/12/28 Award 2014/12/25 Award 2014/12/09 Award 2014/11/26 Award 2014/11/20 Award 2014/11/10 Award 2014/10/31 Award 2014/10/30 Award 2014/10/29 Award 2014/10/17 Award 2014/09/05 Information 2014/08/30 Award 2014/08/28 Award 2014/08/08 Information 2014/06/30 Information 2014/06/11 Information 2014/06/10 Award 2014/05/22 Information 2014/05/09 Award 2014/04/08 Information
2014/03/25 Award 2014/03/20 Information 2014/03/20 Award 2014/01/24 Award 2014/01/20 Information 2013/12/16 Award 2013/11/14 Information 2013/10/09 Award 2013/10/08 Information 2013/10/03 Award 2013/09/25 Award 2013/09/04 Information 2013/08/23 Information 2013/08/23 Information 2013/08/09 Information 2013/07/17 Award 2013/07/01 Information 2013/05/28 Information 2013/05/23 Award 2013/05/14 Information 2013/05/13 Award 2013/04/05 Award 2013/04/02 Information
2013/03/08 Information 2013/01/24 Award 2013/01/18 Information 2013/01/11 Information 2012/12/17 Award 2012/12/12 Information 2012/11/09 Award 2012/11/05 Information 2012/10/19 Award 2012/09/25 Award 2012/09/04 Information 2012/08/24 Award 2012/07/27 Award 2012/04/26 Information
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2019/11/29 Award 2019/11/12 Award 2019/10/30 Award 2019/10/30 Award 2019/10/02 Award 2019/09/22 Award 2019/09/22 Award 2019/08/28 Award 2019/07/11 Award 2019/06/21 Award 2019/06/20 Award 2019/05/09 Award 2019/05/06 Award 2019/04/10 Award
2018/12/13 Award 2018/12/13 Award 2018/11/14 Award 2018/11/14 Award 2018/11/14 Award 2018/07/24 Award 2018/07/16 Award 2018/07/03 Award 2018/05/20 Award 2018/04/09 Award
2017/12/06 Award 2017/11/22 Award 2017/10/26 Award 2017/10/17 Award 2017/10/11 Award 2017/09/19 Award 2017/09/18 Award 2017/08/20 Award 2017/08/02 Award 2017/07/26 Award 2017/07/11 Award 2017/07/08 Award 2017/07/05 Award 2017/06/08 Award 2017/05/16 Award
2017/03/29 Award 2016/12/15 Award 2016/12/12 Award 2016/12/12 Award 2016/11/29 Award 2016/11/09 Award 2016/11/04 Award 2016/11/04 Award 2016/09/14 Award 2016/07/12 Award 2016/06/04 Award
2015/12/09 Award 2015/11/20 Award 2015/11/06 Award 2015/10/28 Award 2015/10/27 Award 2015/10/21 Award 2015/10/01 Award 2015/09/09 Award 2015/07/28 Award 2015/07/12 Award 2015/06/23 Award 2015/04/24 Award
2015/02/04 Award 2015/02/02 Award 2014/12/28 Award 2014/12/25 Award 2014/12/09 Award 2014/11/26 Award 2014/11/20 Award 2014/11/10 Award 2014/10/31 Award 2014/10/30 Award 2014/10/29 Award 2014/10/17 Award 2014/08/30 Award 2014/08/28 Award 2014/06/10 Award 2014/05/09 Award
2013/01/24 Award 2012/12/17 Award 2012/11/09 Award 2012/10/19 Award 2012/09/25 Award 2012/08/24 Award 2012/07/27 Award


Petersburg resident Mark Weaver, 59, awaits an arraignment and status of counsel hearing in Anchorage after the U.S. Marshal's service transferred him from Tacoma, Wash. where he was arrested in late August.
Weaver was indicted by a Grand Jury on two counts of Possession of Unregistered Destructive Devices following an explosion in the Petersburg rock quarry July 13 where he sustained injuries and was subsequently transported to Washington for medical treatment.
Following the incident, local police, the FBI and officials from the Bureau of Alcohol, Tobacco, Firearms and Explosives identified the explosive material at the scene as Tovex, a commercial grade explosive. In subsequent searches of Weaver's property investigators found seven hand grenades.
Weaver is working to obtain private council from attorney Phillip Weidner.
"Mr. Weidner informed the court that he believes he will be proceeding as retained counsel, but that an arrangement has not yet been reached," according to court minutes from Oct. 7.
Weaver's next hearing is scheduled for Oct. 23 at 10 a.m. in Anchorage.


Drop-In Filter Mount Adapter EF-EOS R takes the functionality of Mount Adapter EF-EOS R and adds the ability to use drop-in filters, removing the need to fit filters on the front of a lens, especially useful for wide-angles with a large front lens element. It's available with either a variable neutral density (V-ND) filter or circular polarising (C-PL) filter, and a clear (CL) filter is also available for shooting without filter effects.
Polarising filters cut through glare and haze and reduce the amount of light reflecting from glass surfaces. The filters also boost colour saturation and help add impact to colourful scenes.