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Home Journals JESA Experimental Analysis on the Turning of Aluminum Alloy 7075 Based on Taguchi Method and Artificial Neural Network
Experimental Analysis on the Turning of Aluminum Alloy 7075 Based on Taguchi Method and Artificial Neural Network
Arjun Joshy | Royson Dsouza | Veerakumar Muthirulan | Krishnamurthy H. Sachidananda*
School of Engineering and IT, Manipal Academy of Higher Education, Dubai Campus, UAE
Department of Engineering and Natural Sciences, Tampere University, Finland
sachidananda@manipaldubai.com
This paper mainly aims to disclose the effects of cutting conditions on the turning of aluminum alloy 7075 (AA7075). First, the artificial neural network (ANN) was programmed to investigate how cutting parameters, namely cutting speed, feed rate and depth of cut, affect the surface roughness of AA7075. Then, the taguchi method was introduced to design an L27 orthogonal array, in which each cutting parameter is considered on three levels. The results of orthogonal analysis were used to train the ANN called backpropagation neural network (BPNN) on MATLAB. The trained network was applied to predict the surface roughness of AA7075 through MATLAB simulation. Meanwhile, an experiment was conducted under the same conditions. The experimental results were found consistent with the simulation data, indicating that the BPNN is suitable for simulation the turning of AA7075. It is also learned that the cutting speed has the greatest impact on surface roughness; the surface roughness is negeatively correlated with feed rate; the negative correlation is positively mediated by the cutting speed.
turning, feed rate, cutting speed, depth of cut, surface roughness, artificial neural network (ANN), taguchi method, machining
Metal cutting is one of the most widely used manufacturing process, and its advancement in technology continues to advance in line with the progress in material science development. The increase in productivity and efficiency of the metal removal processes depends on machining parameters such as cutting conditions, cutting tool geometry as well as the work piece and tool material. The optimization of the various parameters of the cutting during the turning process is very important as it is directly related to the surface roughness and power consumed by the machine. The main significance of this research is to predict the surface roughess using ANN method during turning of AA7075 by optimizing the various parameters in order to achieve good surface rougness.
Many researchers have analyzed the various parameters in turing of different materials to optimize the cutting conditions. So based on these research work some of the literature reviews have been presented. According to Siddhpura and Paurobally [1] an important aspect in turning process in manufacturing is to obtain the expected final dimensions and better surface finish [2]. Machinability (ease with which material can be removed) is generally expressed in terms of process responses such as life of the tool, surface finish and power consumed. Out of the above process responses the life of tool is considered to be one of the most important aspects in metal cutting and machinability. Also, with the development of advanced materials it is required to search for new reliable and cost effective metal cutting process to increase the life of cutting tool.
Somashekara and Lakshmana [3] have studied the machining control factors considering cutting speed, feed rate and depth of cut in order to optimize surface roughness while machining aluminum alloy Al 6351-T6 using uncoated carbide tool. The optimization was carried out using Taguchi techniques and they concluded that speed has a major influence on the surface roughness of aluminum alloy. Vaibav and Sachin [4] have studied boring of aluminum material on CNC machining considering cutting speed, feed and depth of cut in order to obtain optimal material removal rate and minimum surface roughness using Taguchi method. They concluded that spindle speed and depth of cut are the most affecting parameters on the surface roughness. Das et al. [5] has studied the surface roughness in CNC turning operation considering spindle speed, feed rate and depth of cut using utility based Taguchi method. The validation and confirmatory test of these parameters was justified using utility based Taguchi method. Sonali et al. [6] have studied optimal machining parameters on aluminum 6061 considering surface roughness. They concluded that spindle speed, feed rate, depth of cut and nose radius have major impact on surface roughness. Wang and Feng [7] have studied surface roughness in turning operation considering workpiece hardness, speed, feed rate, depth of cut, cutting tool point angle and cutting time. They concluded that the metal cutting experiments and corresponding statistical tests developed has produced smaller errors as compared to many other existing models. Nalbant et al. [8] have studied surface roughness prediction considering cutting parameters in CNC turning operation. They used neural network models along with regression models in order to estimate the surface roughness. They concluded that surface roughness prediction using neural network were in line with regression models. Gokkaya and Nalbant [9] have studied the coating type, feed and cutting speed on surface roughness with five different cutting speed. They concluded that surface roughness is inversely proportional to the cutting speed. Dave et al. [10] have studied surface roughness in turned machine parts in order to analyze optimum cutting condition using Taguchi method. They concluded that roughness of the surface plays an important role in machining processes. Kumar et al. [11] have studied the effect of cutting speed, feed rate and depth on cut on surface roughness in CNC turning using Taguchi approach. They concluded that the spindle speed is the most important factor in surface roughness during machining processes. Gupta and Kumar [12] have studied surface roughness and MRR in turning operation using Taguchi method considering nose radius of the tool, rake angle of the tool, cutting speed, feed rate, cutting environment and depth of cut. They concluded that surface roughness increases as feed rate increases. Jafari et al. [13] have studied surface roughness in micro-wire electric discharge machining using Taguchi and ANN method. They concluded that micro-weld parameters have great influence on surface roughness. Palanikumar and Karthikeyan [14] has studied the effects of machining parameters on surface finish in turning composite materials using Taguchi experimental design techniques. They concluded that the analyzed method can be used to study the effect of surface roughness in Al/SiC-MMC composites with 95 % confidence level. Uday et al. [15] have studied four composites in order to analyze the size and volume fraction on machining forces and surface roughness. They concluded that surface roughness values were in line with experimental results when nose radius of the tool is less than the depth of cut. Based on the above literature it is found that many researchers have studied the different aspects of machining parameters such as process kinematics, cooling fluid during machining, step over, depth of cut, angle of the tool, feed rate and cutting speed on surface roughness considering different materials [16]. Karkalos and Angelos [17] have studied the determination of tool life in turning operation considering Taguchi and ANN method. They concluded that in order to get the accurate results the experimental designs and various performance function can be used along with ANN. Sreenivasaulu [18] have studied CNC drilling on Al 6061 considering various cutting parameters using Taguchi and ANN method. They concluded that the comparison of predictive model and the experimental value shows good agreement. Gupta et al. [19] have studied surface parameters considering multi-objective optimization considering Taguchi and grey relation method. They studied concavity, straightness and surface roughness in milling process and they concluded that the optimization of different parameters can be performed using Taguchi and grey relational method. Dahbi et al. [20] have studied turning of 2017A aluminum alloy for measuring various cutting parameters using a CNC lathe machine. They studied the machining parameters and its effect on surface roughness using ANN. They concluded from the developed ANN network that the experimental value was close agreement with the estimated values. Das et al. [21] have studied machining process parameters using ANOVA in turning Al 7075 metal matri composite under heat treated condition. They concluded that the most significant parameters were cutting speed followed by depth.
From the above literature it is observed that many research work using ANN method to optimize surface roughness has been studied for various materials. In this experimental work an alloy of Aluminum Al 7075 which is most commonly used in aeronautical and manufacturing industries has been taken as a material for investigation and the effect of cutting speed, feed and depth of cut on surface roughness [22] using Taguchi and ANN method is considered. The experiments have been performed on Al 7075 material using a CNC turning machine considering speed, feed and depth of cut and its effect on surface roughness has been measured. These experimental results have been analyzed using Taguchi and ANN method. This finding shed new light in optimizing surface roughness by considering various parameters in turing of Al 7075 material using ANN method. The results of the surface roughness optimization clearly show that the experimental values were in good agreement when tested using Taguchi and ANN methods.
2. Methodology
In this research work analysis of variance (ANOVA) using Taguchi method have been used for optimization of speed, feed rate and depth of cut and to study its effects on surface roughness. Then the testing, training and validation of the experimental results with predicted values have been performed using ANN. The material used for the study is aluminum alloy Al 7075. The machining tests were conducted on CNC lathe machine and the technical specifications of the machine is as shown in Table 1.
Table 1. Technical specifications of the MTAB flex CNC machine
Maximum Turning diameter
No. of axis
Spindle Speed Range
150 – 4000rpm
AC Servo
Siemens/ Fanuc/ Mitsubishi
Feed Rate
0-5000 mm/min
1700mm x 1100mm x 1650mm
Automatic Lubrication System
3. Experimental Setup
The experiments were performed on CNC turning machine (MTAB Flex) and the experimental setup is as shown in Figure 1. The experiments were conducted as per Taguchi's L27 orthogonal array. The corresponding dimension of the aluminum workpiece considered for experimentation was having a diameter of 25 mm and length of 100 mm. The specimen was clamped onto the chuck of the machine. The surface roughness measurement was done using surface roughness tester (TR110) which is pocket sized surface roughness measuring instrument suited for on the spot surface measurement quickly. The specifications of the surface roughness instrument is as shown in Table 2. The specimen before machining and after machining is as shown in Figure 2.
4. Design of Experiments
The optimization of the control factors after performing turning operation were done using Minitab 18 software. The corresponding experimental plan is as shown in Table 3. The corresponding values of the surface roughness is as shown in Table 4. The signal to noise ratio (S/N) is a measure in engineering to compare desired signal to background noise. The signal to noise ratio (S/N) for surface roughness values were calculated using smaller-the-better characteristics as per the Taguchi's L27 orthogonal array. The corresponding S/N ratio shown as delta is as shown in Table 5. From this table it is analyzed that the spindle speed is the most effective variable on surface roughness as compared to feed rate and depth of cut.
Figure 1. Experimental machine and experimental set up
Figure 2. a) Before machining b) After machining
Table 2. Technical specifications of the surface roughness tester
Dynamic Display during testing
Ra – 0.05um-15.0um
Tracing length
Tracing Speed
1mm/sec
40 Degree C
3.0V/Li-Ion batteries
102mm x 70mm x 22mm
Table 3. Control factors for experimental setup
Spindle speed, v (rpm)
Feed rate, f (mm/rev)
Depth of cut (mm)
Table 4. Surface roughness values for L27 Orthogonal array
Exp. No.
Spindle Speed. (rpm)
Feed rate (mm/rev)
Depth of Cut. (mm)
Surface Roughness. (Ra)
Table 5. Response table for signal to noise ratio
Feed(mm/rev)
Depth of cut(mm)
Figure 3 (a) and 3(b) shows the main effect plots for S/N ratios and data means. The main objective of S/N ratios is to measure the performance measurement to develop product and processes which are insensitive to variance factors. The signal to noise ratio indicates the degree of the predictable performance parameter of a process in the presence of noise factors. The process parameters with the least signal to noise ratio yield the optimum quality with minimum variance.
Figure 4 (a) and 4(b) shows the surface plots drawn using Minitab 18 software to find the relation between response variable and cutting parameters. These plots show a response variable and its relation with respect to other two factors. The surface roughness can be classified into coarse, rough, medium and fine and if the cutting tool is having greater radius, causes smaller surface roughness values. From Figure 4 it is observed that as the depth of cut and feed increases, surface roughness increases. The lower value of surface roughness can be achieved by maintaining higher level of spindle speed and low levels of feed rate and depth of cut. This increase in surface quality occurs due to high temperature causing easy deformation at the cutting side and around the radius of the cutting tool tip [23].
Figure 3. Main effect plot for S/N ratios (Ra)
Figure 4. Surface plot for surface roughness vs depth of cut, feed
Table 6 shows the analysis of variance (ANOVA) for S/N ratios. From this table it is observed that the values of P less than 0.005 indicates the most significant parameter and in this case spindle speed is the significant parameter as compared to depth of cut and feed rate. From the results of Minitab software it is observed that for turning of aluminum alloy 7075, the spindle speed contributed 54.65% and feed rate and depth of cut contributed 34.67% and 10.47% considering significant interaction effect between spindle speed and depth of cut. The optimum value of surface finish obtained for machining aluminum alloy 7075 are spindle speed of 1200 rpm, feed rate of 60 mm/min and depth of cut 0.4 mm.
Table 6. ANOVA for SN ratios
Adj SS
Adj MS
Depth of cut
Residual Error
5. Predictive Modelling for Surface Roughness Using Artificial Neural Network (ANN)
Artificial neural networks (ANN) are used to develop models similar to the human brain processes information. A large amount of uncertain and noisy data can be efficiently processed in human brain through neural network. These neural networks attempt to mimic the functioning of biological neurons and hence generate intelligent decisions. These decisions are fundamental processed in a neural network through neurons, which possess a memory which is local for carrying out localized information processing operations. These neurons are interconnected using uni-directional channels of signal called connection into multi-level networks. Each neuron is having a single output, which then branches into as many number of collateral connections as required. Each neuron carries the same original signal as the neuron output signal. These neuron signals can be of mathematical coded type apart from electrical and chemical signals. The signal processing under each neuron should be completely local and it depends on the current values of the arriving input signal through impinging connections and compare the values which is stored within the neuron's local memory. There are many kinds of architectures based on neural network which includes Adaptive resonance (ART) models, Back-propagation models, Hopfield models, Kohonen's models etc. have been designed and developed and signals are broadcasted uni-directional from the neuron input layer through the neuron hidden layers to the outside layers [24]. The attainment of the neural network is strongly influenced by the selection of network structure [25], algorithm, training, testing, transfer, learning and performance characteristics function. In this research paper feed-forward back-propagation neural network model has been adopted (refer Figure 5).
Figure 5. Architecture of the proposed artificial neural network structure
5.1 Normalization of input data
Before inputting the data in multilayer feed forward back propagation neural network, it is required to perform the normalization of the input and output data [26]. Normalization is a process of transformation which is performed on the data in order to distribute and range it into an acceptable scale for further analysis. In this research work, the normalization of the data sets is in the range of 0.1-1 [27] and was performed using the Eq. (1) as shown below [28].
$N=0.1+0.9\left(\frac{x-X_{\min }}{X_{\max }-X_{\min }}\right)$ (1)
where, X = actual value, Xmin = minimum value, Xmax = maximum value and N = normalized value corresponding to X.
An increase in the amount of data during training will always increase the chance of getting more exact model. In case of machining the corresponding data for training is taken from the experimental trails. There are so many constraints for the researcher such as cost of experiments and time consumed in conducting the actual experiment in order to get more data for the modelling. But from several studies it is observed that using lesser amount of modelling samples it is possible to get good models during testing and training. Cus et al. [29] have obtained good results for predicting surface roughness with very less amount of training and testing data. They took a sample of 27 in order to predict surface roughness using ANN model during their experimentation. When the testing data used by programmers is smaller than the training data, then it is needed to isolate the available experimental samples into separate training and testing. In these cases it is recommended to use guidelines given by Zhong et al. [30] and they have recommended that the ratio of training and testing samples could be 90% : 10%, 85% : 15% and 80% : 20%. In this research, the experimental sample considered was 27 and hence 80% : 20% preferred ratio was selected.
5.2 Training of developed ANN
From Figure 6 (a) it is observed one dashed line and one blue line. The dashed line shows perfect fit whereas blue line shows a linear fit. The best agreement between the experimental and predicted values during the ANN training model is specified by the equation as predicted value = 0.87 * experimental value + 0.079 which clearly represents excellent association between experimental and predicted values of surface roughness.
Figure 6. Comparison between experimental and predicted surface roughness during a) training, b) testing and c) validation
5.3 Testing of ANN developed model
Figure 6(b) shows the comparison of predicted surface roughness and the experimental model during testing of ANN model. From this figure it is observed dotted line and the other red line. The dotted line shows perfect fit while red line shows the linear fit. The best agreement between the experimental values and predicted values during testing of the ANN model is given as predicted value = 1 * experimental value +0.042 which clearly represents interrelationship between experimental and predicted surface roughness values.
Figure 6 (c) shows the correlation between experimental and predicted values of surface roughness during validation. From this figure it is observed one dashed lines and the other a solid green line. The dashed line shows perfect fit whereas green line shows a linear fit. The best agreement between the experimental values and predicted values during validation of the ANN model is given as predicted value = 0.99 * experimental value +0.0013 which clearly shows excellent correlation between experimental surface roughness values with the predicted surface roughness values.
The artificial neural network that was developed is trained for the input as well as for the output values. The benchmark for stopping the training depends upon the number of epochs and is considered in this research work as 1000 epochs. The simulation of the network is conducted for both input values and the target values during experiments. The input values for the network is trained during the test readings and then the target obtained is compared with the actual output. The predicted surface roughness (Ra) values are compared with the experimental (Ra) surface roughness values and the comparison show minimal variations.
The predicted value of surface roughness (Ra) is compared with the measured average values of surface roughness (Ra) and the absolute percentage error is computed, as per the Eq. 2 given below [30]:
$\%$ Absolute error $=\left|\frac{R_{\text {aActual}}-R_{\text {aPredicted}}}{R_{\text {aActual}}}\right| \times 100$ (2)
where, Ra,Actual = measured value and Ra,Predicted = ANN predicted value.
Table 7. Predicted value by ANN
Experiment No.
Surface roughness (Ra)
Normalized Ra
Average Ra
Figure 7. Correlation between experimental and predicted surface roughness
Table 8. Predicted values of Absolute error
Spindle speed(rpm)
Feed rate(mm/rev)
Difference (Actual-Predicted)
The experimental roughness values thus obtained have been estimated for each set of values and the same is measured with predicted roughness values as shown in Table 7 and Table 8. The performance of surface roughness with respect to other parameters is analyzed and its influence on surface roughness is carried out and identified from the experiments. The percentage difference between actual surface roughness values and predicted surface roughness values is as shown in Table 7 and from this the average percentage of error is 8.28%.
7. Comparison of Graphical Results Between Experimental and Predicted Surface Roughness
Figure 7 shows the graph of error profile of experimental and the predicted roughness for 27 input trials. The maximum absolute percentage error during training patterns was found to be around 1 and 0.96 for actual and predicted values respectively. From this it is evident that ANN can be used to predict the surface roughness and the performance of the trained network can be further estimated by using a regression analysis between the network and the corresponding targets.
In this research work CNC turning operation have been performed on aluminum alloy 7075 material and the surface roughness have been measured by considering machining parameters such as spindle speed, feed rate and depth of cut. The optimization of the process has been performed using analysis of variance (ANOVA). By using ANN model the prediction of surface roughness has been performed using feed-forward back-propagation method. The model has been evaluated based on the percentage deviation between the predicted surface roughness (Ra) vales and the actual surface roughness (Ra) values. Based on this research work, the following conclusions have been drawn.
The effective prediction of the surface roughness of the material for various machining parameters (cutting speed, feed rate, depth of cut etc. as input variables) have been analyzed.
For lower cutting speeds, as the cutting speed increases, the surface roughness values decrease. Also, for higher feed rates the surface roughness values changes considerably.
Based on ANOVA results, spindle speed has significant impact as compared to feed rate and depth of cut.
ANN model has achieved an accuracy of 87.07% between various parameters considered for the study.
The average actual surface roughness (Ra) value have been obtained is 0.3359 mm and the predicted surface roughness value is 0.3496 mm.
This method of optimization of surface roughness in turning of Al 7075 techniques using Taguchi and ANN method can be further studied for different materials.
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The Gold Claddagh Ring
As A Wedding Band
This article on the Gold Claddagh Ring is part of an interview with Jonathan Margetts, jeweller and owner of the oldest license to produce this traditional ring. See his shop front on the photo below.
Johnathan, how did the ring become famous?
At some stage during the early to mid eighteen hundreds, the ring business exploded. It became a symbol for Galway. The Claddagh people started using it as a wedding band. The Claddagh became the main Connemara wedding ring, too.
People were very poor then, and the price of gold in relation to what their annual income would have been was huge, compared to today. Yet, they bought gold Claddagh rings for wedding bands. The rings were a piece of financial security I think, as much as a symbol of love and wedlock. They had to save up for it for a very long time, and often had to settle for cheaper gold.
But a ring was an investment that you could always keep safe because it was on your body. You could melt it down or cash it in if needed in hard times. This is the reason actually why there are so few old gold Claddagh rings left. Most of them got melted down. But if you managed to hold onto it, it then became a family heirloom passed to your eldest daughter.
Johnathan Margett's with our daughter, Tara, at his jewellery shop on Quay Street, Galway, Ireland.
The Claddagh symbol of the hands, heart and crown is nowadays used on all sorts of items, not just rings. You get other jewellery such as earings, cufflinks, pendants, and many non- jewellery items such a T-shirts and souvenirs bearing the Claddagh symbol. You also find it on signage and in company logos.
One Galway taxi company uses the symbol as a logo replacing the heart with a car.
In the last forty years, especially the Claddagh ring has become absolutely huge. Everyone loves it. I get a lot of Asian customers, Koreans, Japanese and Chinese, as well as Americans and some Germans. People love the investment of buying gold and silver. And I think what people respond to in the Claddagh ring is the symbolism of the image. It appeals to us all. Love, friendship and loyalty are what everyone wants in a relationship and hopefully the symbol will help people find what they are looking for.
Some of the contents at this quaint Galway shop on Quay Street.
Jonathan, why is the ring called a Claddagh ring?
Nobody knows who coined the term 'Claddagh' ring.
Funnily enough, the Claddagh people themselves don't use that word. They call it 'heart and hands ring'instead.
The ring was never made in the Claddagh. It was always made in the town of Galway, across the bridge. But virually everyone in County Galway wore it as a wedding ring from the 1750ies.
More About The Gold Claddagh Ring
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redpajama_set_name: RedPajamaCommonCrawl


Get The Ring: How to Find & Keep the Right One for Life.
shouldn't be a customer, obviously. This is how they act only to people who do business with them. Which means, they're willing to give as long as you give back to them.
In a marriage, the kind of giving has to be — giving because you care about the next person.
Now I know it works both ways. Not only are you going to be giving to the next person, the next person will be giving to you as well. It has to work that way because a marriage is where you love each other, and if one is giving to the other without it having go both ways, then you could have a situation where… let's say, the husband may love his wife passionately and she really doesn't care too much about him, because he's been giving to her selflessly throughout these years while she hasn't been giving to him. It could be vice versa. It could be that she loves him passionately and he couldn't really care about her. After a marriage of one decade, two decades, you could have a situation where one is passionately in love with the other one, where the other one really doesn't care too much about the person that loves them. It's quite a tragedy to be trapped in a relationship like that, and that's why the love has to go both ways. So while you're looking for somebody who is kind and who can give love, you have to look for someone who you can love as well.
I remember a story one time a friend of mind told to me about relatives of his, married for 25 years, and then one day he got rich. And after he got rich and he realized that he had more possibilities in life than he thought existed beforehand he just picked up and he left. And she would take him back any day of the week because she really loved him. She had cared for him, she had helped him for 25 years, and during this time he simply took and took and took, never really giving back anything. And so when the time came that he could leave, he did it without a problem. And she still is waiting for him to return.
That's really a tragedy. So what you're saying is that we should be looking for someone who's going to give to us and at the same time will motivate us to give to them.
So yes, it has to work both ways.
So marry a person that you want to give to. There are some types of people that, as soon as we meet them they generate within us a sense of compassion and care. When you're looking for someone to marry, therefore, don't just see if they are kind, also make sure that you feel like being kind to them. A person who arouses in you a sense of compassion.
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Agoston, Csaba Gábor and Várnagy, Katalin and Bényei, Attila and Sanna, Daniele and Micera, Giovanni and Sóvágó, Imre (2000) Solution equilibria and structural characterisation of the transition metal complexes of glycyl-L-cysteine disulfide. Polyhedron, Vol. 19 (15), p. 1849-1857. ISSN 0277-5387. Article.
Stoichiometry, stability constants and structure of the complexes formed in the reaction of copper(II), nickel(II), zinc(II), cobalt(II) and cadmium(II) with (GlyCys)2 containing disulfide bond were determined by potentiometric, UV–Vis, NMR and EPR spectroscopic methods. The complex [Ni(GlyCys)2·H2O] was prepared in the solid state and its structure determined by single crystal X-ray diffraction method. Disulfide sulfur atoms of (GlyCys)2 were not metal-binding sites in any of the systems studied in solution or in the solid state. It was found that copper(II) is able to induce deprotonation and coordination of the peptide amide nitrogen donor atoms. This resulted in the formation of [CuL], [Cu2H−2L] and [CuH−1L]− as the major species in solution. In the case of nickel(II), cobalt(II), zinc(II) and cadmium(II) the complex [ML] predominates, and the outstanding stability of this species was explained by the formation of a macrochelate between the (NH2, CO)-coordinated five-membered chelates in solution. Crystal structure of [Ni(GlyCys)2·H2O] revealed the octahedral geometry of nickel(II) in a polymeric structure.
Pubblicato online l'11 settembre 2000.


For the last few years, Winston-Salem's Foothill's Brewery has thrown one of the biggest release parties.
The line to buy 22-oz. bottles will start on the sidewalk outside the pub. You're welcome to show up anytime after we close at 2am the previous evening. Or just bid on a spot in line!
Bottle sales will commence at 10am. Those in line will be summoned in order of their wristband number in groups of 50. Bottle prices and limits will be set closer to release, and will be based on overall yield of this year's brew.
There will be no growler fills of Sexual Chocolate.
You can read about 2013's Sexual Chocolate event at CCD HERE.


Testing out my video camera. I went around the block without using my hands (after getting started and shifting in the first 100ft. Roughly about 1/3 a mile. The gap between the truck and the shrub was about 5ft.


text:
Sjöwall and Wahlöö, The Terrorists
April 16, 2011 Rohan Maitzen
I've just finished reading three more of the Martin Beck books by Maj Sjöwall and Per Wahlöö: The Abominable Man, Cop Killer, and The Terrorists, which are, respectively, numbers 7, 9, and 10 in the series. There are now only two I haven't read (The Man on the Balcony and The Locked Room)–not by design but because they haven't turned up in the library or at any of the used bookstores I haunt. I think that the eight I've read have given me a very good idea of the series as a whole, and my interest in and respect for what Sjöwall and Wahlöö do in it has only increased as I've read along. By the end of the final book the scope and intensity of their critique of contemporary Swedish society has finally become explicit. It is even, finally, articulated at length, rather than gestured at through repeated jabs by the characters and in the narration or through the accumulating examples of incompetence, hypocrisy, and stupidity we got in book after book. It's interesting that it's a relatively peripheral character who finally voices the most sustained piece of social criticism in the series. It is carefully prepared for, in The Terrorists, by the juxtaposition of an "actual" terrorist cell that engineers two political assassinations (one of which is ultimately unsuccessful) with a very different kind of attack by someone who, as her lawyer argues, may have committed murder but is best understood as a victim. The terrorists' attacks are not glorified: in fact, we get a rare close-up of brutality from one of the main characters when two of them are finally cornered (I'm trying to avoid really explicit spoilers, as it is quite a suspenseful story!):
He felt the hatred welling up inside him, a wild, uncontrollable hatred against these people who killed for money without caring who they killed and why. . . . [he] proceeded to smash his opponent's face and chest repeatedly against the wall. On the last two occasions, [the man] was already unconscious, his clothes soaked with blood, but [he] kept his grip and raised the large limp body, ready to strike again.
"That's enough now," says Martin Beck, but there's no sign that anyone, including Beck, is surprised or moved in any way by the violence shown. In contrast, the alt-assassin is treated sympathetically–during her initial interrogation (which even seems the wrong term to use) Beck offers her food, proposes that they resume after she's had a rest, and generally gives her every consideration. There's no question that her action is political, in the broadest sense of the word. She aims (pun intended!) at the head of a state that has shown her only indifference or hostility through its pervasive but ineffective bureaucracies. Nobody in particular has done her any harm: the problems and injustices she faces are systemic. What recourse does one individual have, in such a situation? "She realized," her lawyer explains, "that someone must bear the responsibility"–and so she has acted, with a slightly pathetic naïveté. 'It does seem a bit pointless," one policeman remarks; "They'll find another one just like him inside half an hour." But her lawyer suggests, that "she is wiser and more right-thinking than most of us." It's almost a call to revolution, except that it's so carefully embedded within the particularities of the case and of the wind-bag lawyer that its risk is contained. Still, it's out there, as an idea, and the direction of our sympathies towards someone who has basically turned political terrorist because of the repeated small ways she has, in her own private life, been terrorized, is consistent with the overall message of the series that violence generates violence, and that we should not be too quick to equate legality with justice.
There is quite a lot of violence in The Terrorists, some of it quite gruesome. The tone is never sensational, though, only dispiritedly matter-of-fact, even when a head decapitated by an explosion strikes an officer in the chest. The grim potential of these moments is also leavened by Sjöwall and Wahlöö's characteristic dry humor, which perfectly conveys the attitude of rueful stoicism shown by most of the police officers. The one who is struck in the chest, for instance, is immediately upset about his nice suit. Later the head of a decapitated dog is displayed as evidence and the annoyingly smarmy and incompetent Superintendent, Stig Malm, "at once threw up on the floor," a moment which gave me more gratification than it probably should have because his bad police work has cost a lot of lives across the series. The cynicism that drives the series is also on full display, as when the proceedings against the apprehended terrorists are described as "among the most farcical that had even been enacted in any Stockholm courtroom." If we had any lingering idealism about the system that has failed the first accused assassin, it's dispelled here. After the case and the evidence against the men has been presented, we get this:
"I oppose the arraignment," said the defense counsel.
"Why?" asked the judge, a flash of genuine surprise in his voice.
The defense counsel sat in silence for a moment, then said, "I don't really know."
With this brilliant remark, the proceedings collapsed…
We end the book, and the series, on an ambivalent note. On the one hand, we settle down for a pleasant evening with four of our main characters,
just the kind of evening everyone hopes for more of. When everyone is relaxed and in tune with themselves and the world around them. When everyone has eaten and drunk well and knows they are free the next day, as long as nothing too special or horrible or unexpected happens.
If by "everyone" we mean a very small group of humankind.
Four people, to be exact.
The restoration of order and domestic harmony promised by the form of the detective novel is offered but promptly rejected or subverted. Even if that harmony is achieved, it is only for the fortunate few, and even they enjoy it only precariously, only until it is broken once again. In the Martin Beck books, such happy moments actually happen often, but it seems to be a law that the more comfortable you are with your aquavit and your book, or your lover, the more likely it is that the phone will ring and pull you back into the corrupt world. What hope does one individual have against all the wrongs, all the injustices, all the stupidity? The one person who has taken a stand in this book has been labelled insane and locked away, destroyed, not helped. Martin Beck's long-time partner, Lennart Kollberg, offers his friend some consoling perspective: "Violence has rushed like an avalanche throughout the whole of the Western world over the last ten years. You can't stop or steer that avalanche on your own. It just increases. That's not your fault." "Isn't it?" asks Beck. "Kollberg … looked at Martin Beck and said, "The trouble with you, Martin, is just that you've got the wrong job. At the wrong time. In the wrong part of the world. In the wrong system." "Is that all?" Becky drily responds.
The final word of the series goes to Kollberg, and, as has been widely noted, is "Marx." Certainly there's plenty of disgust expressed for capitalism, by characters but also through theplots of the novels and their typical allocation of guilt and innocence. The Terrorists even has a long screed against Christmas, which "had changed from a fine traditional family festival into something that might be called economic cheapjackery or commercial insanity." The defense lawyer's statement explicitly condemns the way "large and powerful nations within the capitalist bloc have been ruled by people … who from a lust for power and financial gain have led their peoples into an abyss of egoism, self-indulgence and a view of life based entirely on materialism and ruthlessness toward their fellow human beings."
Clearly these are books with a political agenda, and moments like these are didactic, riskily so. I think they are dramatically effective, however, because they are rare, and because the series shows no crusading or utopian zeal. In its world, systems are necessary. Bureaucracies are imperfect but essential. Some good police work is better than none; trying to find a just outcome is better than not trying. Change is slow. Work is hard. Patience is a virtue. Life is bleak, but there are small pleasures, like dinner with friends. Martin Beck has no illusions, but he still shows up every day and does his job. It's an unimpressive but ultimately quite moving form of moral heroism.
I think I may choose The Terrorists for my class in the fall. Usually when approaching a series I assign the first one, as it often makes most obvious what is going to be different, how this author will bend and reshape the conventions of the genre. That also gets me out of the awkward backstory problem (teaching Gaudy Night, I'm always tempted to [and often do] interject with context from the previous books). But here, though I think all the ones I've read are outstanding, and Roseanna would be a really interesting book to read right after studying hard-boiled detective fiction and then Ed McBain, I think this one makes the political work Sjöwall and Wahlöö are doing most evident, and that is something that really does make their series distinct. It shows a conviction (one often echoed by today's practitioners of the genre, such as Ian Rankin) that the detective novel really be both artistically effective and ideologically significant, and not just as a means for celebrating and protecting the status quo. That doesn't mean Sjöwall and Wahlöö are necessarily successful or persuasive in every aspect of their project, but I think it will give us a lot to talk about.
Mysteries, Sjowall, Maj, and Per Wahloo
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10 thoughts on "Sjöwall and Wahlöö, The Terrorists"
thewritingwoman April 16, 2011 / 4:07 pm
I don't often go for this genre as I usually end up prioritising others but this posting has reminded me that I do actually enjoy it. I haven't read any of the Martin Beck books but your enthusiasm makes me fell as if this is a woeful omission in my cultural frame of reference.
Ta muchly!
Chelsea April 16, 2011 / 5:55 pm
I've not only never really dabbled in crime fiction, or even really mysteries for that matter, and although Sweden is an area of the world I've hardly ever read about or focused on, this review has made me want to do both! I also think that this book sounds like an interesting one to assign to a class, especially to talk about issues like physical violence versus more manipulative forms as well as the intersections between literature and social commentary. Thanks for the great review!
Rohan Maitzen April 17, 2011 / 10:39 am
@thewritingwoman, I was steered to these books when I had a hard time grasping the appeal of Henning Mankell's, and not only have I found them extremely smart and interesting on their own, but they have also helped me understand better the tradition Mankell and other Scandinavian crime writers are working in. But the bottom line for me is just that they are very good books on their own terms.
@Chelsea, I get tired of crime fiction easily, because so much of it is so formulaic, but there are some writers and series I think show what can be done within the conventions of the genre, and these books are definitely now on that list. I don't know that it has made me want to go to Sweden, though! 🙂
Amateur Reader April 17, 2011 / 11:37 am
What would it mean for Sjöwall and Wahlöö to be "successful or persuasive in every aspect of their project"? The revolutionary overthrow of democratic government? Something else? I wonder.
What makes me ask is your last sentence there, that they don't make you want to go to Sweden. Isn't Sweden kind of, I don't know, kind of awfully nice? To what extent are Sjöwall and Wahlöö, and Mankell, trying to represent the Sweden they observe, and to what extent is it a dark fantasy Sweden?
This is not a criticism – I am pro-fantasy!
Rohan Maitzen April 17, 2011 / 4:01 pm
@AR: I meant to question whether they are 'successful' rhetorically, as in, I don't know if their (basically Marxist) critique is justified or coherent (not knowing anything, myself, yet, about Sweden in the 1960s and 70s)–I've read some commentaries that find nothing better than leftist posturing in it. I don't think they really are calling for violent revolution, since the overall tone of the books is (I think! again, much of my analysis is really preliminary here) resigned. I suspect that's why they gave the defense lawyer that big speech, not Beck: it contains it.
My understanding is that Sjowall and Wahloo are deliberately reacting against the idea that Sweden is "awfully nice," bringing out the sordid realities that they see papered over by a tendentious rhetoric and image of the happy people's state. Characters often bring up statistics about suicide rates and depression a lot, for instance, and many cases involve people who are let down by institutions that are supposed to care for them. In Cop Killer there's a whole scenario with a miserable, understaffed, antiquated hospital. And so on. On their view, it's the nice Sweden that's a fantasy. From Liza Marklund's introduction to Cop Killer:"The Scandinavian countries, and perhaps Sweden above all, have long had an ambivalent attitude where their own excellence is concerned. There is a streak of self-righteousness in us that is only partially justified. It is certainly true that our standard of living is the highest in the world, our infant mortality rate low, our proportion of women in politics high: we are extremely fortunate. At the same time, there are obvious cracks in the Swedish social democratic ideal of the "People's Home," and they have been there for a long time. . . . There, in the gap between utopia and reality, Maj and Per found a truth that they as authors became tremendously interested in investigating. . . . The books . . . starkly highlighted the discrepancy between society's wishful visions and the real lives of the ordinary people, revealing the consequences of society's failure."
Amateur Reader April 17, 2011 / 9:37 pm
I don't want to pretend that an invocation of Marx ins 1975 Sweden means the same thing that it would in a different time or place. I know enough about the history of French and Italian Communism to be wary.
But what, then, does it mean? In the context of a crime novel, one that is specifically about political violence, I doubt they are interested in the Swedish state nationalizing Volvo or reducing their Gini coefficient from .25 to .23.*
That last quotation you give returns us to the 19th century, doesn't it, to Dickens and Gaskell and so on. Maybe less materialism, less ruthlessness, more sympathy is the answer. But maybe the emphasis should be on "ruled" – maybe the "rulers" can be replaced.
I'm not really arguing with the book, and I read Roseanna long ago and liked it all right. I'm just curious about how much punch the political statement is really supposed to have. How much can detective fiction – any fiction – actually do?
* I could look that last bit up, but I think Sweden, circa 1970, had the most equal income distribution of any free country. A 0.25 Gini is the rough statistic I'm carrying around. Could be wrong!
Rohan Maitzen April 18, 2011 / 9:25 am
Argue away! I'm curious, though, about your question about the "punch" or effect of the political statement. I suppose it does what any writing does, which is offer us a perspective on the world, a way of looking at it, a set of questions to ask about it. Fiction also is often given credit for putting a human face on social problems and trying to move people emotionally as well as intellectually. And some have argued that detective fiction in particular has more potential reach for this re-visioning mission because the familiarity of the genre makes it possible to move marginal perspectives / ideas further into the mainstream. Is this action? Is this "actually" doing something? Well, both yes and no, right? Writing (or reading) is not voting, or financial reform, or political activism in itself, but people take these next steps only as the result of their thinking about the world they live in,
But this is all pretty obvious as a reply, and you've already named Dickens and Gaskell in this context, so what I'm curious about is why this book in particular makes you fretful about its political efficacy or its socio-economic theory. Is it because its political aims seem quite overt? (Mind you, I've picked these bits out of a 300-page novel, so it's not quite as didactic as I've made it seem.)
The CIA World Fact Book gives the Gini index for Sweden in 2005 as .23, down from .25 in 1992. I can't (easily, at least) dredge up information about 1970. I note this, from the very authoritative site Wikipedia: "Sweden has a low Gini coefficient for income distribution but a significantly higher Gini coefficient for wealth (for instance 77% of the share value owned by households is held by just 5% of Swedish shareholding households)." Obviously, I would need to do better research than this to do my own analysis of the economics of mid-20thC Sweden–though I wouldn't presume to do that, but would just to grasp enough to contextualize Sjowall and Wahloo's perspective.
If the Gini is 0.25 now, it would have been substantially lower, using that calculation, in 1970. Sweden has experienced a similar pattern of increasing income inequality as everyone else.
But this is part of what makes me fretful. If what we really want is a higher marginal income tax on the wealthy, or a more equitable distribution of income, or improvements in the bureaucratic efficacy of the social safety net, Karl Marx is unnecessarily powerful medicine. So I suspect there is something else behind it.
In that Marklund quote, there seems to be a mixup of which side represents "reality" and which "utopia." If the reality is one of the lowest homicide rates in the world, perhaps some self-righteousness – or, let's say, pride in the fact – is in order.
Annie April 21, 2011 / 7:11 am
Rohan, sorry I should have posted here before but the weather has been so good here over the past few days that I've had to get to work in the garden – something I hate. I'm the black sheep in a long line of market gardeners!
As you've seen, I've just read the first of these novels and so I'm not really in a position to comment on the social and political implications of the series as a whole. However, given the 'punishment' the Swedish system takes in the Larsson novels I would be surprised if someone hadn't decided to challenge the populist view in previous books. For myself, while I will be interested in the way that side of the novels develops, I'm going to be much more concerned to look at the way the writers deal with the narrative arc and whether they will try to sustain it over all ten novels as well as in the individual books. Unfortunately, in order to assess that I really ought to read them straight through, but getting hold of the earlier volumes is proving difficult and to look at what I'm interested in I definitely have to read them in order.
I'm not much of a gardener myself. Luckily, it will be June before gardening season begins here anyway!
That's a very interesting issue about the narrative arc of the books. There are certainly continuities, and different characters go through their own arcs, but I wonder if there's a large-scale story across all ten books. They aren't hard to find electronically, by the way–here, at least, they are available through Kobo in the nice new Vintage editions.


The mode of Christ's presence under the Eucharistic species is unique. ... In the most Blessed Sacrament of the Eucharist "the Body and Blood, together with the soul and divinity, of our Lord Jesus Christ and, therefore, the whole Christ is truly, really, and substantially contained." "This presence is called 'real' - by which is not intended to exclude the other types of presence as if they could not be 'real' too, but because it is presence in the fullest sense: That is to say, it is a substantial presence by which Christ, God and man, makes Himself wholly and entirely present."
By "entirely" present, it is meant that every quality and aspect of Jesus Christ--His hair, His eyes, His emotions--are fully and totally present, though hidden under sacramental forms, whenever we visit Him reposed in the tabernacle or exposed in a monstrance during Adoration and Benediction.
This also means that whenever we receive Holy Communion, we should not refer to the consecrated Host as "bread" (because it is actually not bread) but truly as the Body of the living, resurrected Christ; similarly, we should not refer to "wine" (because it is actually not wine) but to the Precious Blood of our Savior.
This reminds us of the blood ritual with which the covenant was ratified at Sinai (Ex 24) -- the sprinkled blood of sacrificed animals united God and Israel in one relationship, so now the shed Blood of Jesus on the cross is the bond of union between new covenant partners -- God the Father, Jesus, and the Catholic Christian Church. Through Jesus' sacrifice, all the baptized are in relationship with God, although the fullness of the truth subsists in the Catholic Church, the Church instituted by Christ and entrusted to His apostles (with Peter as their head) and their successors, i.e., the bishops who are in communion with the successor of St. Peter (the Pope), the Bishop of Rome (see CCC 816, 820, 830). This "handing on" of the faith (what "Tradition" means) from generation to generation through the teaching of the apostle's successors (bishops) assures us that the Church, divinely guided by the Holy Spirit, receives and develops faithfully the teachings of the Lord Jesus to His apostles; in other words, it is essential that the Church be "apostolic," i.e., connected by succession to the apostles, the 12 disciples to whom Jesus entrusted His Church, because apostolic succession is a guarantee of being connected with the original Church that Jesus promised His eternal guidance and protection (Matthew 16:18).
Receiving the Eucharist changes us. St. Augustine would say, "Be what you see; receive what you are"--the Body of Christ. It signifies and effects the unity of the community, the mystical (spiritual and invisible) Body of Christ and serves to strengthen each member.


text:
Q: LinkedList (2.0): removing items iteratively I need to iterate through a LinkedList<T> (in .NET 2.0) and remove all the items according to a given criteria.
It was easy way under Java, since I could do the following:
Iterator<E> i = list.iterator();
while (i.hasNext()) {
    E e = i.next();
    if (e == x) {
        // Found, so move it to the front,
        i.remove();
        list.addFirst(x);
        // Return it
        return x;
    }
}

Unfortunately, in the .NET behavior of IEnumerator<T> (the equivalent of Iterator<E>) there's no remove method to remove the current element from the collection.
Also, in the LinkedList<T> there's no way to access an element at a given index, to accomplish the task by iterating back from the last to the first.
Have you got any idea on how to do it? Thank you very much!

A: This will remove all nodes that match a criteria, in one loop through the linked list.
LinkedListNode<E> node = list.First;

while (node != null)
{
    var next = node.Next;
    if (node.Value == x) {
        list.Remove(e);
    }
    node = next;
}

I believe that's what you're attempting... You also added back in the node at the beginning of the list (so your java code didn't remove all of the nodes, but rather moved the first matching to the beginning of the list).  That would be easy to do with this approach, as well.

A: It's actually a lot easier in C#.
function PlaceAtHead(<T> x)
{
   list.Remove(x);
   list.AddFirst(x);
   return x;
}

A: One ugly option is to iterate through your list, find all the items that apply and store them in a list.  Then iterate through your second list and call remove on your LinkedList...
I'm hoping someone else has a more elegant solution :)

A: Just a little addition to Reed Copsey's answer with a predicate:
    public static T MoveAheadAndReturn<T>(LinkedList<T> ll, Predicate<T> pred)
    {
        if (ll == null)
            throw new ArgumentNullException("ll");
        if (pred == null)
            throw new ArgumentNullException("pred");

        LinkedListNode<T> node = ll.First;
        T value = default(T);

        while (node != null)
        {
            value = node.Value;
            if (pred(value))
            {
                ll.Remove(node);
                ll.AddFirst(node);
                break;
            }
            node = node.Next;
        }

        return value;
    }

redpajama_set_name: RedPajamaStackExchange


text:
Viu Announces Exclusive Rights To New Korean Drama Series "One Ordinary Day"
Posted on September 9, 2021 November 26, 2021
Viu, PCCW's leading pan-regional OTT video streaming service, announces that the highly anticipated Korean crime-thriller drama, One Ordinary Day, will be exclusively available on its platform. After announcing a series of high profile Viu Korean Original series like Lovers of The Red Sky and Now We are Breaking Up, Viu brings yet another much-awaited K-drama to its audiences.
Set to premiere on Viu on November 27, 2021, One Ordinary Day boasts some of South Korea's top actors, including Kim Soo-hyun, who last starred in the hit K-drama It's Okay To Not Be Okay, veteran actor Cha Seoung-won, and Less Than Evil actress Lee Seol.
The stellar cast headlines One Ordinary Day, which is based on the gripping British drama Criminal Justice. In the Korean remake, the story revolves around two men whose lives change completely after a woman is found murdered. Kim Soo-hyun plays an ordinary college student Kim Hyun-soo who, after one drunken night of fun, finds himself the prime suspect in the gruesome murder of a woman he had spent the night with. With all circumstantial evidence pointing at him and the case receiving increasing scrutiny in the media and on social media, the prosecution is eager to declare him guilty.
The only person who comes forward to take his case is Shin Joong-han (played by Cha Seoung-won), a small-time lawyer who barely passed the bar exam. He decides to help Hyun-soo on his intuition that he is innocent. With the odds stacked against them, the pair must put up an intense fight to bring justice and reveal the real perpetrator in a case that will not only change their lives, but also shake the criminal justice system of the country.
One Ordinary Day is produced by Chorokbaem Media (Penthouse, Rookie Historian Goo Hae Ryung), Studio M and Gold Medalist (It's Okay to Not Be Okay). Written by Kwon Soon-gyu (The Royal Gambler, Warrior Baek Dong Soo, Jackpot), the drama is directed by established director, Lee Myung-woo (Backstreet Rookie, The Fiery Priest, Punch, Whisper).
With the release of Lovers of The Red Sky this week on the platform, Viu has ensured that Viu-ers have something exciting to come to every month. The fantasy romance historical drama starring Ahn Hyo-seop, Kim Yoo-jung, Gong Myung and Kwak Si-yang is already becoming very popular amongst K-drama lovers. This is the third Viu Korean Original series after the highly successful River Where the Moon Rises and Doom At Your Service.
One Ordinary Day will be preceded by yet another blockbuster K-drama of the year, Now We are Breaking Up, starring top-grade actress Song Hye-kyo, scheduled to launch on November 12 as a Viu Original. In 2021, Viu has been the home to some of the most anticipated simulcast K-dramas from Korea including The Penthouse series, Sell Your Haunted House, Taxi Driver, and Police University.
Ms. Marianne Lee, Chief of Content Acquisition & Development, Viu, said, "Viu is determined to bring the best of Asian entertainment to our viewers. From investing in original productions to securing the exclusive rights to top Korean drama series, Viu constantly offers enthralling shows with a wide selection of Korean content on one convenient platform for our audiences."
Viu-ers in Hong Kong, Singapore, Malaysia, Indonesia, Thailand, the Philippines, Myanmar, India, United Arab Emirates, Saudi Arabia, Qatar, Kuwait, Bahrain, Oman, Jordan, and Egypt will be able to watch One Ordinary Day exclusively on Viu from November 27, 2021. This series and other top performing titles can be watched on the Viu app which can be downloaded for free on the App Store, Google Play, and selected smart TVs, as well as on the web at http://www.viu.com.
Posted in Press ReleaseTagged Cha Seung Won, Kim Soo Hyun, Lovers Of The Red Sky, Now We Are Breaking Up, One Ordinary Day, Viu, Viu Original, Viu Philippines
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We are thrilled to share that The Last Wolf by Maria Vale, Bad Bachelor by Stefanie London, and Bellewether by Susanna Kearsley are 2019 RITA award finalists!
The Last Wolf is a finalist for Best First Book and Paranormal Romance, Bad Bachelor for Contemporary Romance: Long, and Bellewether for Mainstream Fiction with a Central Romance.
The RITA is recognized as the highest award of distinction in romance fiction. Up to 2,000 novels are entered annually in over thirteen different categories. The RITA winners will be announced at the RWA National Conference this summer (July 25-28, 2019).
Click "read more" below to learn more about each book and author.
Maria Vale is a journalist who has worked for Publishers Weekly, Glamour magazine, Redbook, the Philadelphia Inquirer. She is a logophile and a bibliovore and a worrier about the world.Trained as a medievalist, she tries to shoehorn the language of Beowulf into things that don't really need it. She currently lives in New York with her husband, two sons and a long line of dead plants. No one will let her have a pet.Visit her online at mariavale.com.
Everybody's talking about the hot new app reviewing New York's most eligible bachelors. But why focus on prince charming when you can read the latest dirt on the lowest-ranked "Bad Bachelors"—NYC's most notorious bad boys.
If one more person mentions Bad Bachelors to Reed McMahon, someone's gonna get hurt. A PR whiz, Reed is known as an 'image fixer' but his womanizing ways have caught up with him. What he needs is a PR miracle of his own.
When Reed strolls into Darcy Greer's workplace offering to help save the struggling library, she isn't buying it. The prickly Brooklynite knows Reed is exactly the kind of guy she should avoid. But the library does need his help. But as she reluctantly works with Reed, she realizes there's more to a man than his reputation. Maybe, just maybe Bad Bachelor #1 is THE one for her.
Stefanie London is the USA Today bestselling author of contemporary romance and romantic comedy. Her books have been called "genuinely entertaining and memorable" by Booklist, and her writing was praised as "elegant, descriptive and delectable" by RT Magazine.
Originally from Melbourne, Australia, Stefanie now lives in Toronto, Canada with her husband. She loves to read, collect lipsticks, watch zombie movies and drink coffee. Her bestselling book, Pretend It's Love, was a 2016 Romantic Book of the Year finalist with the Romance Writers of Australia.
You can visit her at www.stefanie-london.com.
It's late summer, war is raging, and families are torn apart by divided loyalties and deadly secrets. In this complex and dangerous time, a young French Canadian lieutenant is captured and billeted with a Long Island family, an unwilling and unwelcome guest. As he begins to pitch in with the never-ending household tasks and farm chores, Jean-Philippe de Sabran finds himself drawn to the daughter of the house. Slowly, Lydia Wilde comes to lean on Jean-Philippe, true soldier and gentleman, until their lives become inextricably intertwined. Legend has it that the forbidden love between Jean-Philippe and Lydia ended tragically, but centuries later, the clues they left behind slowly unveil the true story.
Part history, part romance, and all kinds of magic, Susanna Kearsley's latest masterpiece will draw you in and never let you go, even long after you've closed the last page.


text:
Bert's Newsagents, 112 Timbercroft Lane, Plumstead, SE18 2SG
Bert's Newsagent, 112 Timbercroft Lane, Plumstead, London, SE18 2SB
In reaching its decision, the Sub Committee considered the Council's Statement of Licensing Policy, the Licensing Act 2003, the Regulations made thereunder and the Guidance issued by the Secretary of State under S.182 of that Act. In discharging its functions, the Sub-Committee did so with a view to promoting the licensing objectives of the prevention of crime and disorder, public safety, the prevention of public nuisance and the protection of children from harm.
Having considered the application for the Premise Licence and all written and oral submissions, the Sub-Committee granted a Premises Licence for the Supply of alcohol for consumption off the premises.
Permitted hours for the supply of alcohol:
9am to 11pm
Note: The original application had sought permission to supply alcohol from 6am to 11 pm daily.
The Premises Licence is granted subject to the following conditions:
1. The premises shall operate Greenwich Council's 'Reducing the Strength' Scheme. This means that the premises shall not sell any beers, lager or cider with an ABV of 6.5% or above unless agreed in writing with the Police Licensing Team.
2. The premises shall operate the 'Challenge 25' Scheme. Under the scheme, staff authorised for the sale of alcohol shall challenge every individual who appears to be under 25 years of age and shall refuse service where individuals cannot produce acceptable means of identification to prove they are over 18. Notices shall be displayed as to the age verification policy, advising customers that if they look under 25, they may be asked to provide evidence of age. Acceptable forms of ID shall be:
a) A UK Driving Licence;
b) A valid passport;
c) A Home Office approved ID card.
3. Signage informing customers of the age verification policy adopted at the premises shall be prominently displayed.
4. All staff shall be trained in the law relating to the sale of alcohol. Such training shall include challenging every individual who appears to be under 25 years of age and to refuse service where individuals cannot produce acceptable means of identification; understanding acceptable forms of ID; and using the Refusal Register. Such training (including any refresher training) shall be recorded and provided not less than every twelve (12) months. The training record shall be made available for inspection by Police and "authorised persons" (as defined by Section 13 of the Licensing Act 2003).
5. A Refusals Register shall be kept at the premises, and made immediately available on request to the police or authorised persons. The Refusals Register shall be inspected on a monthly basis by the Designated Premises Supervisor and the date of inspection noted in the register, and a record made in the register of any actions that appear to be needed to protect young people from harm. The register shall record all refused sales of alcohol and include, but not be limited to, the following:
a) The identity of the member of staff who refused the sale;
b) The date and time of the refusal;
c) The alcohol requested and reason for refusal;
d) Description of the person refused alcohol.
6. The CCTV shall continuously record whilst the premises is open for licensable activities and during all times when customers remain on the premises. The CCTV shall cover inside and outside of the premises (precise positions may be agreed with Police from time-to-time). The recorded CCTV images shall be stored for a minimum of thirty-one (31) days with the correct date & time-stamping.
7. A member of staff who can operate the CCTV system and download copies of recordings upon request by Police or an authorised person shall be present on the premises during all hours that the premises remains open to members of the public.
8. The premises shall display signs stating that the premises are monitored by CCTV. Such signage shall be displayed on the front door and inside the premises.
9. An Incident Book shall be maintained at the premises to record details of any incidents which compromise the licensing objectives pursuant to the Licensing Act 2003. Such entries shall include, but not be limited to, the following:
a) All crimes at the venue, e.g. shoplifting, damage, threats to staff;
b) Removal of patrons from the premises;
c) Any complaints received;
d) Any incidents of disorder;
e) Any faults in the CCTV system;
f) Any visit by an authorised officer or emergency service.
10. The area immediately outside the premises shall be maintained in a clean and tidy manner at all times it is open for licensable activity.
The Sub-Committee considered submissions from the Applicant's representative and the applicant. The newsagency business has been operated by the applicant's family and the applicant since 1958. The Applicant resides above the premises and he himself went to the primary school opposite. The concerns of the police had been addressed by agreement of conditions to be imposed upon the premises licence it were to be granted.
The Sub-Committee noted the written representations from 3 residents who were not present for the hearing.
There were no representations from any Responsible Authorities against the application.
The concerns regarding prevention of harm to children and the proximity of the primary school to the premises had been properly addressed by agreement with the police.
The premises are not within a Cumulative Impact Zone.
The Sub-Committee considered that the conditions subject to which the Premises Licence is granted promote the licensing objectives and that the premises will be operated responsibly.
Right of Appeal:
If the applicant or those making representations are aggrieved by the Council's decision, they have the right to appeal to the Magistrates' Court.
Any appeal must be submitted to the Magistrates' Court within 21 days of the date of written notification of the decision.
LSCR-Bert's Newsagents, 112 Timbercroft Lane, SE18 PDF 144 KB
APPX A(1) - Application PDF 12 MB
APPX A(2) - Plan ~ COLOUR PDF 5 MB
APPX B - Agreement to Police Rep -- Conditions PDF 295 KB
APPX C - Agreement to Police Rep -- Hours PDF 340 KB
APPX D - Map PDF 12 MB
APPX E - Police Rep PDF 1 MB


You can use the EuroConvert function to convert a number to euro or from euro to a participating currency. You can also use it to convert a number from one participating currency to another by using the euro as an intermediary (triangulation). The EuroConvert function uses fixed conversion rates established by the European Union.
The number you want to convert, or a reference to a field containing the number.
A string expression, or reference to a field containing the string, corresponding to the International Standards Organization (ISO) acronym for the currency you want to convert. Can be one of the ISO codes listed in the following table.
In the preceding table, the calculation precision determines what currency unit to round the result to based on the conversion currency. For example, when converting to Deutsche marks, the calculation precision is 2, and the result is rounded to the nearest pfennig, 100 pfennigs to a mark. The display precision determines how many decimal places appear in the field containing the result.
Later versions of the EuroConvert function may support additional currencies. For information about new participating currencies and updates to the EuroConvert function, see the Microsoft Office Euro Currency Web site.
A string expression, or reference to a field containing the string, corresponding to the ISO code of the currency to which you want to convert the number. For a list of ISO codes, see the sourcecurrency argument description.
Optional. A Boolean value where True (1) ignores the currency-specific rounding rules (called display precision in sourcecurrency argument description) and uses the 6-significant-digit conversion factor with no follow-up rounding. False (0) uses the currency-specific rounding rules to display the result. If the parameter is omitted, the default value is False.
Optional. An Integer value greater than or equal to 3 that specifies the number of significant digits in the calculation precision used for the intermediate euro value when converting between two national currencies.
Any trailing zeros are truncated and invalid parameters return #Error.
If the source ISO code is the same as the target ISO code, the original value of the number is active.
This function does not apply a format.
The EuroConvert function uses the current rates established by the European Union. If the rates change, Microsoft will update the function. To get full information about the rules and the rates currently in effect, see the European Commission publications about the euro. For information about obtaining these publications, see the Microsoft Office Euro Currency Web site.
The first example converts 1.20 Deutsche marks to a euro dollar value (answer = 0.61). The second example converts 1.47 French francs to Deutsche marks (answer = 0.44 DM). They assume conversion rates of 1 euro = 6.55858 French francs and 1.92974 Deutsche marks.


text:
Mehrwertige Logik ist ein Oberbegriff für alle logischen Systeme, die mehr als zwei Wahrheitswerte verwenden.

Ausgangspunkt für die Entwicklung mehrwertiger Logiken war die erkenntnistheoretische Frage, ob dem Prinzip der Zweiwertigkeit außerlogische Wahrheit zukommt. Für Aussagen über die Zukunft stellt bereits Aristoteles diese Frage, indem er argumentiert, dass die Wahrheit einer Aussage wie "Morgen wird eine Seeschlacht stattfinden" erst am Abend des morgigen Tages feststehen wird und dass sie bis zu diesem Zeitpunkt noch als unbestimmt und damit als kontingent möglich betrachtet werden muss.

Die erste im modernen Sinn formalisierte mehrwertige Logik ist die im Jahre 1920 von Jan Łukasiewicz vorgestellte dreiwertige Logik L3. Ihre drei Wahrheitswerte interpretiert Łukasiewicz unter Berufung auf das Seeschlacht-Beispiel des Aristoteles als "wahr", "falsch" und – für zukünftige Aussagen, deren Wahrheit noch nicht feststeht – "(kontingent) möglich".

In neuerer Zeit haben mehrwertige Logiken im Bereich der Informatik hohe praktische Bedeutung gewonnen. Sie ermöglichen den Umgang mit der Tatsache, dass Datenbanken nicht nur eindeutig bestimmte, sondern auch unbestimmte, fehlende oder sogar widersprüchliche Informationen enthalten können.

Grundlagen mehrwertiger Logik

Während mehrwertige Logik mit dem Prinzip der Zweiwertigkeit eines der beiden Grundprinzipien der klassischen Logik aufgibt, behält sie deren anderes Grundprinzip, das Extensionalitätsprinzip, bei: Der Wahrheitswert jeder zusammengesetzten Aussage ist weiterhin eindeutig durch die Wahrheitswerte ihrer Teilaussagen bestimmt.

Im Gegensatz zur klassischen Logik ist die Deutung der Wahrheitswerte bei mehrwertigen Logiken weniger natürlich vorgegeben. Es sind zahlreiche unterschiedliche Interpretationen vorgeschlagen worden. Aus diesem Grund und weil viele Deutungen, die mehr als zwei Werte nicht als Abstufungen oder Arten von Wahrheit und Falschheit ansehen, sondern zum Beispiel epistemisch als Abstufung von Erkenntnis oder Gewissheit (zum Beispiel mit den drei Werten "als wahr bekannt", "unbekannt" und "als falsch bekannt"), werden die Werte mehrwertiger Logik häufig nicht als Wahrheitswerte, sondern als Pseudowahrheitswerte oder als Quasiwahrheitswerte bezeichnet. Aus Gründen der Kompaktheit verwendet dieser Artikel dennoch durchgehend die Bezeichnung "Wahrheitswert".

Neben dem Problem der Deutung der Wahrheitswerte stellen sich beim Umgang mit mehrwertiger Logik zahlreiche Aufgaben technischer Natur und es ergeben sich weitere Deutungsprobleme: Grundlegende Begriffe wie jener der Tautologie, jener der Kontradiktion oder jener der Folgerung müssen neu definiert und gedeutet werden.

 Tautologien und designierte Wahrheitswerte
 In der klassischen Logik sind Tautologien definiert als Aussagen, die immer (das heißt ungeachtet dessen, wie die in ihnen auftretenden atomaren Aussagen bewertet werden) wahr sind. Um den Begriff "Tautologie" für die mehrwertige Logik nutzbar zu machen, muss man einen oder mehrere der Pseudowahrheitswerte auszeichnen. Der Begriff "Tautologie" lässt sich dann an die mehrwertige Logik anpassen, indem man all jene Aussagen als Tautologien bezeichnet, die stets, das heißt unter jeder Bewertung, einen der ausgezeichneten Wahrheitswerte annehmen. Diese ausgezeichneten Wahrheitswerte nennt man auch designierte Wahrheitswerte.
 Kontradiktion und negativ designierte Wahrheitswerte
 Will man den Begriff "Kontradiktion" auf die mehrwertige Logik ausdehnen, so hat man dazu zwei Möglichkeiten: Man kann einerseits einen oder mehrere der Wahrheitswerte negativ hervorheben und dann all jene Aussagen als Kontradiktionen bezeichnen, die immer – das heißt unter jeder Bewertung – einen negativ designierten Wahrheitswert liefern. Andererseits kann man eine Aussage als Kontradiktion bezeichnen, deren Negation eine Tautologie ist. Vorausgesetzt wird dabei, dass eine geeignete Negation zur Verfügung steht und geklärt ist, welche der mehrwertigen Negationen für diesen Zweck geeignet ist.
 Folgerung
 Mit Hilfe des Konzepts der designierten Wahrheitswerte lässt sich der Folgerungsbegriff analog zu jenem der klassischen Logik leicht auf mehrwertige Logik ausdehnen: Ein Argument ist demnach genau dann gültig, wenn unter allen Bewertungen, unter denen alle Prämissen des Arguments designierte Wahrheitswerte annehmen, auch seine Konklusion einen designierten Wahrheitswert annimmt.

Systeme mehrwertiger Aussagenlogik

Kleene-Logik K3

Die Kleene-Logik  enthält drei Wahrheitswerte, nämlich 1 für "wahr", 0 für "falsch" und , das hier auch als i bezeichnet wird und für "weder wahr noch falsch" steht. Kleene definiert die Negation , Konjunktion , Disjunktion  und Implikation  durch folgende Wahrheitswertfunktionen:

Damit bildet – wie zum Beispiel auch bei Łukasiewiczs dreiwertiger Logik , siehe dort – die Disjunktion das Maximum und die Konjunktion das Minimum der verknüpften Wahrheitswerte und errechnet sich die Negation einer Aussage mit Wahrheitswert v als 1-v.

Betrachtet man 1 als einzigen designierten Wahrheitswert, dann gibt es in  keinerlei Tautologien; betrachtet man sowohl  als auch 1 als designiert, dann ist die Menge der Tautologien in  identisch mit der Menge der klassischen, zweiwertigen Aussagenlogik.

Gödel-Logiken Gk und G∞

Gödel definiert 1932 eine Familie mehrwertiger Logiken  mit endlich vielen Wahrheitswerten , sodass zum Beispiel  die Wahrheitswerte  und  die Wahrheitswerte  umfasst. Analog definiert er eine Logik mit unendlich vielen Wahrheitswerten, , bei der als Wahrheitswerte die reellen Zahlen im Intervall von 0 bis 1 verwendet werden. Designierter Wahrheitswert ist bei jeder dieser Logiken 1.

Die Konjunktion  und die Disjunktion  definiert er als Minimum bzw. Maximum der Formelwahrheitswerte:

Die Negation  und Implikation  werden durch folgende Wahrheitswertfunktionen definiert:

Die Gödelschen Systeme sind vollständig axiomatisierbar, d. h., es lassen sich Kalküle aufstellen, in denen alle Tautologien des jeweiligen Systems herleitbar sind.

Łukasiewicz-Logiken Lv

Die Implikation  und die Negation  definiert Jan Łukasiewicz durch folgende Wahrheitswertfunktionen:

Als erstes entwickelt Łukasiewicz nach diesem Schema 1920 seine dreiwertige Logik, das System , mit den Wahrheitswerten  und designiertem Wahrheitswert 1. 1922 folgt seine unendlichwertige Logik , in der er die Menge der Wahrheitswerte auf das Intervall der reellen Zahlen von 0 bis 1 erweitert. Designierter Wahrheitswert ist in beiden Fällen 1.

Verallgemeinert zu  zerfallen die Łukasiewicz'schen Logiken in die endlichwertigen Systeme  (Wahrheitswertmenge wie bei Gödel ), in das bereits angesprochene  und in , bei der als Wahrheitswerte die rationalen Zahlen (d. h. Brüche) im Intervall von 0 bis 1 verwendet werden. Die Menge der Tautologien, das heißt der Aussagen mit designiertem Wahrheitswert, ist bei  und  identisch.

Produktlogik Π

Die Produktlogik enthält eine Konjunktion  und eine Implikation , die folgendermaßen definiert werden:

 für :

Zusätzlich enthält die Produktlogik eine Wahrheitswertkonstante , die den Wahrheitswert "falsch" bezeichnet.

Mittels der zusätzlichen Konstanten können eine Negation  und eine weitere Konjunktion  folgendermaßen definiert werden:

Post-Logiken Pm

Post definiert 1921 eine Familie von Logiken  mit (wie bei  und ) den Wahrheitswerten . Negation  und Disjunktion  definiert Post folgendermaßen:

Vierwertige Logik von Belnap

 Hauptartikel: Belnaps vierwertige Logik

Nuel Belnap entwickelte 1977 seine vierwertige Logik mit den Wahrheitswerten t (true, wahr), f (falsch), u (unbekannt) und b (beides, also einer widersprüchlichen Information).

Bočvar-Logik B3

Die Bočvar-Logik (von Dmitrij Anatoljewitsch Bočvar, geschrieben auch Bochvar oder Botschwar)  enthält zwei Klassen von Junktoren, nämlich die inneren Junktoren einerseits und die äußeren Junktoren andererseits. Die inneren Junktoren Negation , Implikation , Disjunktion , Konjunktion  und Bisubjunktion  entsprechen denen der klassischen Logik. Die äußeren Junktoren Negation , Implikation , Disjunktion , Konjunktion  und Bisubjunktion  sind metasprachlicher Natur und sind die folgenden:

  ( ist falsch)
  (ist  wahr, so auch )
  ( ist wahr oder  ist wahr)
  ( ist wahr und  ist wahr)
  ( ist wahr gdw  ist wahr)

Die Wahrheitswertfunktionen entsprechen denen der Kleene Logik .

Für die Definition der äußeren Junktoren wird ein weiterer einstelliger Junktor hinzugenommen, nämlich die externe Bestätigung  mit der Wahrheitswertfunktion

Damit lassen sich die äußeren Junktoren, wie folgt, definieren:

Die Logik der äußeren Junktoren, welche eine Unterscheidung zwischen 0 und i trifft, entspricht exakt der klassischen Logik.

Bayeslogik
Die Bayeslogik (auch Bayes-Logik oder induktive Bayes-Logik) ist eine induktive mehrwertige Logik aus dem Grenzfeld von Logik, Erkenntnistheorie und Maschinenlernen mit Anwendungen in den Bereichen Psychologie und Mensch-Computer-Interaktion.

Die Bayeslogik bestimmt die rationale subjektive Gültigkeit oder probabilistische Adäquatheit von logischen Prädikationen (etwa "Raben sind schwarz UND können fliegen") induktiv nach Regeln der Wahrscheinlichkeitstheorie. Ihre Ergebnisse können sich bei weiteren Daten wieder verändern (sie ist "non-monoton"). Die Wahrscheinlichkeitstheorie wird auf der Ebene alternativer logischer Erklärungsmuster (die sich aber überlappen können) angewendet. Bei Gegebenheit bestimmter Annahmen, kann die Bayeslogik dadurch den rationalen Grad der Adäquatheit von logischen Erklärungsmustern (logischen Junktoren) bestimmen und etwa die beste Erklärung aufgrund von Häufigkeitsdaten und Vorerwartungen bestimmen (Schluss auf die beste Erklärung). Nach dem Satz von Bayes gilt P(Junktor i|Daten) = P(Daten|Junktor i)*P(Junktor i) / P(Daten). Dabei wird hier von einer Likelihood-Funktion ausgegangen, die bei Ausnahmen einer Junktor-Hypothese nicht immer eine Wahrscheinlichkeit von Null zuordnet, falls ein Ausnahmeparameter r echt größer als 0 ist (r>0). Bei Ausnahmeparameter r = 0 und vorliegenden Daten, die einer Junktor-Hypothese widersprechenden, folgt auch hier eine falsifikationistische Adäquatheitsnorm des Hypothesentestens: Eine einzige gegenlaufende Evidenz widerlegt eine Hypothese. Bei fehlender Widerlegung wird, wie im Falsifikationismus auch, die spezifischere (logisch 'stärkere') Hypothese aufgrund einer Bayesschen Version von Ockhams Rasiermesser bevorzugt. Bei r > 0 erlaubt die Bayeslogik auch die Bevorzugung von spezifischeren Hypothesen – selbst wenn sie mehr Ausnahmen zulässt. Trotz der Datenbasierung (extensionaler Aspekte), handelt es sich insofern um eine auch intensionale Logik, die unter manchen Bedingungen auch psychologische deskriptiv gute Ergebnisse zeigt und eventuell eine rationale Erklärung, etwa von Konjunktionsfehlern (Conjunction Fallacy), bieten kann, die scheinbar im Widerspruch zu einer unmittelbaren Anwendung der Wahrscheinlichkeitstheorie zu stehen scheinen.

Fuzzy-Logik

In der Fuzzy-Set-Theorie, oft auch als Fuzzy-Logik bezeichnet, werden ebenfalls nicht eindeutige Aussagen behandelt. Ein Beispiel ist die Aussage "das Wetter ist sehr warm". Diese Aussage wird, abhängig von der tatsächlichen Temperatur, in unterschiedlichem Ausmaß zutreffen: bei 35 Grad mit Sicherheit, bei 25 Grad einigermaßen, bei 0 Grad auf keinen Fall. Die willkürlich festzulegenden Grade des Zutreffens werden durch eine reelle Zahl zwischen 0 und 1 repräsentiert.

Die vorstehenden mehrwertigen Logiken behandeln einzelne Aussagen als atomar, kennen deren innere Struktur also gar nicht. Im Unterschied dazu behandelt die Fuzzy-Set-Theorie nur Aussagen mit einer sehr speziellen inneren Struktur: Einer Grundmenge möglicher Beobachtungen (z. B. die auftretenden Temperaturen) werden Grade des Zutreffens einer Aussage ("ist sehr warm") zugeordnet. Der Begriff Menge (engl. set) in fuzzy set, bezieht sich auf die Menge der Beobachtungen, bei denen der Grad des Zutreffens der Aussage > 0 ist; der Begriff fuzzy deutet auf den variablen Grad des Zutreffens.

Die Fuzzy-Set-Theorie behandelt nicht die Frage, ob es unbekannt oder zweifelhaft ist, ob eine Aussage zutrifft. Einer Aussage als solcher wird überhaupt kein Wahrheitswert zugeordnet; die Grade des Zutreffens sind keine Wahrheitswerte, sondern eher Interpretationen eines originären gemessenen Werts.

Die Fuzzy-Set-Theorie liefert auch Methoden, den Grad des Zutreffens von Aussagen, in denen mehrere elementare Aussagen verknüpft sind ("das Wetter ist warm und trocken"), zu bestimmen. Die Verfahren zur Kombination von Zutreffensgraden können teilweise auch auf die Kombination von Wahrheitswerten der mehrwertigen Logiken angewandt werden.

Anwendung mehrwertiger Logiken

In der Hardwareentwicklung von Logikschaltungen werden mehrwertige Logiken zur Simulation eingesetzt, um verschiedene Zustände darzustellen sowie Tri-State-Gatter und Busse zu modellieren. In der Hardwarebeschreibungssprache VHDL wird zum Beispiel oft die im IEEE-Standard mit der Nummer 1164 definierte neunwertige Logik verwendet, die Standard Logic 1164. Sie hat die Werte

 U undefiniert
 X unbekannt (starker Treiber)
 0 logische Null (starker Treiber)
 1 logische Eins (starker Treiber)
 Z hochohmig (hohe Impedanz Z)
 W unbekannt (schwacher Treiber)
 L logische Null low (schwacher Treiber)
 H logische Eins high (schwacher Treiber)
 – unwichtig don't care

Standard Logic 1164, eine neunwertige Logik zur Hardwaresimulation

In einer realen Schaltung treten nur 1, 0 und (bei Ein-/Ausgängen) Z auf. In der Simulation tritt der Zustand U bei Signalen auf, denen bisher noch kein anderer Wert zugewiesen wurde. Der Wert - (Don't-Care, wird außerhalb von VHDL oft mit X dargestellt) dient nur zur Synthese; er signalisiert dem Übersetzungsprogramm, dass ein bestimmter Zustand nicht vorgesehen ist und es daher egal ist, wie die synthetisierte Schaltung mit diesem Zustand umgeht.

Die Unterscheidung zwischen starken und schwachen Treibern dient dazu, in einem Konfliktfall (wenn zwei Ausgänge auf eine einzige Leitung zusammengeschaltet sind und verschiedene Werte liefern) zu entscheiden, welches Signal der entsprechenden Leitung zugeschrieben wird. Dieser Konflikt tritt oft bei Bussystemen auf, wo mehrere Busteilnehmer gleichzeitig anfangen, Daten zu senden. Trifft nun eine 1 (stark) auf ein L (schwach), so setzt sich das starke Signal durch, und der Signalleitung wird der Wert 1 zugeschrieben. Treffen jedoch gleich starke Signale aufeinander, so geht die Signalleitung in einen undefinierten Zustand. Diese Zustände sind X (bei Konflikt zwischen 1 und 0) und W (bei Konflikt zwischen H und L).

Abgrenzung
Mehrwertige Logiken werden oft unter metaphysischen oder erkenntnistheoretischen Fragestellungen diskutiert. Darunter fällt z. B. die häufig gestellte Frage, welches logische System "stimmt", d. h. welches logische System die Wirklichkeit richtig (oder besser: am besten) beschreibt. Unterschiedliche philosophische Strömungen geben auf diese Frage unterschiedliche Antworten; einige Strömungen, z. B. der Positivismus, lehnen gar die Fragestellung an sich als sinnlos ab.

Literatur
 Lothar Kreiser, Siegfried Gottwald, Werner Stelzner (Hrsg.): Nichtklassische Logik. Eine Einführung. 2. Auflage. Akademie-Verlag, Berlin 1990, ISBN 978-3-05-000274-3.
 Alexander Alexandrowitsch Sinowjew: Über mehrwertige Logik. Ein Abriß. Deutscher Verlag der Wissenschaften, Berlin 1968. (Auch Braunschweig: Vieweg und Basel: C.F. Winter. ISBN 978-3-528-08271-0)
 Siegfried Gottwald: Mehrwertige Logik. Eine Einführung in Theorie und Anwendung. Akademie-Verlag, Berlin 1989, 1995, ISBN 978-3-05-000765-6.

Weblinks

 Journal of Multiple-Valued Logic and Soft Computing
 Nuel Belnap:
 Zitate zu Nuel Belnap: A Useful Four-valued Logic

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