Ethnomathematics Exploration of Jong Sailboat Shape As a Traditional Game in the Riau Islands

Abstract


INTRODUCTION
Indonesia is the largest archipelagic country globally, consisting of approximately 17,508 islands with 1,904,569 km 2 , which stretches between the Asian Continent and the Australian Continent. The thousands of islands that are owned by Indonesia make Indonesia known as a maritime country. Ethnicities and diverse cultures and their uniqueness have made Indonesia's government increasingly recognized by other countries. Especially neighboring countries are directly adjacent to the Indonesian State, such as Malaysia, Singapore, Papua New Guinea, Timor Leste, Brunei Darussalam, and other adjoining.
One of the provinces that have the most islands in Indonesia is the Riau Islands Province. Almost all areas of the Riau Islands Province are directly adjacent to neighboring countries; there are 11 entry points and cross-border between Indonesia and Malaysia, and Singapore [1]. It is a challenge for people in the Riau Islands Province, often eliminating the local border area's culture with these two neighboring countries. However, it depends on the people who take advantage of this kind of situation. If a culture is well preserved and developed, this can be a good selling point and become one of the attractions for tourists abroad. So we need to know one of the changes in intercultural relations between local and foreign cultures [2].
Understanding of cultural diversity does not grow by itself in the order of people's lives. Still, it must be socialized through statutory regulations, an interactive dialogue involving all nation components, mass media, and multicultural education to create a teaching and learning process without cultural differences [3]- [5].
The Riau Islands have various kinds of cultures; especially, the majority of the population has a Malay culture. Culture is defined as knowledge that includes beliefs, traditional arts, morals, customs, and human thinking abilities. Culture can also be interpreted as the whole thought, work, and work of humans who have no sense of their instincts and are only triggered by humans after the learning process that can create ideas or ideas in the human mind [6]. A form of a cultural way of life-related to creativity, taste, and intention grows and develops in a society owned by a group of people. It is passed on continuously from the top generation to the lower generations [7].
Culture is formed from many elements, elements of Malay culture, which have many works and arts. One form of work and skill that is still preserved is traditional games. The regular game that is always held in the Riau Islands is the Jong Sailboat. Jong Sailboat is a small Sailboat made of wood, shaped as best and as good as possible by the maker to sail by itself following the wind.
Jong Sailboat is one of the cultures of the Riau Islands community. On this Jong Sailboat, there is an indication that it is part of ethnomathematics. Ethnomathematics is a unique method used by a specific cultural group or community group in mathematical activities [8]. It can be interpreted that mathematical activity is a process of abstracting the real experiences in the form of mathematics or vice versa, which includes activities, counting, measuring, designing buildings or tools, making patterns, counting, determining the game's location, explaining, and so on. Ethnomathematics has a broader meaning than just ethno (ethnicity), but ethnomathematics is defined as the cultural anthropology of mathematics and mathematics education [9]. In other words, ethnomathematics is mathematics that appears due to the influence of activities in an environment influenced by culture [10]. Thus the culture of mathematics can take different forms and develop following the community's development who wears it [11].
This definition provides information; the results of ethnomathematics studies can be obtained through exploration, which is field exploration to gain more knowledge (about a situation). It can be concluded that ethnomathematics raises cultural wisdom to motivate students to learn mathematics. In learning mathematics, several abilities affect students' learning achievement, including mathematical ability, which is the literacy of mathematics itself. Mathematical literacy can be defined as knowledge of applying basic mathematics in everyday life. Mathematical literacy includes a person's ability to formulate, apply, and interpret mathematics. It is divided into various contexts, including mathematical reasoning, using concepts, procedures, and facts or phenomena [12].
Not only that, interest in learning is very influential on the quality of students. A study reveals that students will interact and connect mathematical ideas if the effort to solve each mathematics project's problems is impressive. It connects mathematical ideas with imagination and the real world as learning objectives by linking local culture as objects [13]. So with this explanation, ethnomathematics can be found through exploration of the Jong Sailboat form, which has mathematical concepts and mathematical elements in it that can be used by educators to teach mathematics as well as introduce culture to students.
Many research types on ethnomathematics exploration were carried out before this, including the investigation in traditional Javanese games [14]. Ethnomathematical exploration of the Marawis musical instrument style as a source of learning mathematics [15]. Ethnomathematics exploration of Cirebon Trusmi batik reveals philosophical values and mathematical concepts [16], and ethnomathematics in traditional games of Engklek and Gasing, typical of the Sundanese culture [17], development mathematics learning devices Pugung Raharjo Archaeological Site [18]. From these researchers, it can be seen that there are activities that contain mathematical concepts and practices in every culture in a place. Likewise, the objects that will be examined in this study indicate mathematical concepts and techniques.
The study to be carried out is different from previous research that the researchers have described. The difference from this research is the research object, where the item of this research object is the Jong Sailboat's shape. The researcher took this object because there was no ethnomathematics study on the Perahu Layar Jong shape. The researcher took this object because there was no ethnomathematics study on the form of the Jong Sailboat. In the research on Jong Sailboat's record, apart from the researchers exploring the ethnomathematics, the researchers also introduced Indonesia's Malay cultures, namely the traditional Jong Sailboat game.
Therefore, researchers are interested in exploring the Jong Sailboat form's mathematical concepts or practices, with the research title "Ethnomatic Exploration of the Jong Sailboat Forms as Traditional Games in the Riau Islands". Educators in the learning process can use the ethnomathematics exploration results in the form of Jong Sailboat. Educators can think of mathematical material by the results of this exploration; with this, the cultural elements of Jong Sailboat can be packaged in such a way as to the learning process of mathematics.
The research problem's formulation explores and describes the Jong Sailboat's ethnomathematics as a traditional game of the Riau Islands, a traditional game of Riau Islands.

METHOD
This type of research is qualitative with an ethnographic approach. The research subjects chosen were makers or crafters of the Jong Sailboat traditional game. Selection of research subjects using purposive sampling, namely determining the sample with specific considerations [19]. Its research was conducted in Penyengat Island, Tanjungpinang City, Riau Islands province.
Data collection was carried out by interview, observation, and documentation with the leading research instrument. Researchers go directly to the field to collect data. The data were then analyzed by referring to Miles and Huberman's design by reducing the data, presenting the data, and concluding/verification [20]. Furthermore, domain analysis and taxonomic analysis were carried out in the data reduction process, so that the domain in this study was chosen, namely the design domain.
In collecting data, the following stages were carried out; 1. In determining the data source, the selected data source is a reliable data source that can provide valid research data. 2. After finding the source of the data, they were followed by conducting interviews. In this study, the type of interview used is semi-structured interviews, where the implementation follows the interview guidelines, but the questions can develop according to the circumstances. The interviewed informants were also open in expressing their opinions on any items to be asked.
3. In conducting observations, observations made are participatory in type; namely, the researcher is directly involved with the activities carried out by the informants. In this research, the action referred to is assembling and assembling the parts of the Jong Sailboat. 4. In doing documentation, documentation is carried out by interview and observation. The documentation meant here is that the researcher takes photos of the research subject, namely the forms of Jong Sailboats that are deemed necessary. 5. They were writing field notes, written field notes containing the results of interviews, observations, and documentation that the researcher obtained while in the field. 6. Making data reduction, in this process, the researcher summarizes the results of interviews, observations, and documentation so that they can focus on things that are important and by the research objectives. 7. Perform data presentation, data presentation in the form of pictures, and short narrative descriptions. The content of presenting the data is discovering mathematical concepts in Jong Sailboat, the Riau Islands' traditional game. 8. Withdrawing conclusions, conclusions are obtained based on the data presented in the form of mathematical concepts found from the results of ethnomathematics exploration in the way of Jong Sailboats.

RESULTS AND DISCUSSION
At present, there has been a lot of research on ethnomathematics, as the researchers have described in the introduction, namely exploration in traditional Javanese games where mathematical concepts have been found, namely in the form of number operations, flat shapes, congruence, number comparisons, and relations [14], ethnomathematics exploration of the musical instrument style of the marawis art as a source of learning mathematics where mathematical concepts have been discovered, namely in the form of flat plane geometry and mathematical concepts which include the concepts of translation, reflection, folding symmetry, rotating symmetry, acute and obtuse angles, and circular planes [15], exploration of Cirebon Trusmi batik ethnomathematics to reveal the philosophical values and mathematical concepts that have been found in mathematical concepts, namely the concepts of symmetry geometry, transformation (reflection, translation, and rotation), and congruence [16], and ethnomathematics in traditional games of cranks and tops typical of a Sundanese culture where mathematical concepts have been found, namely in conventional cranks games there are flat geometric concepts, namely square, rectangle, semicircle, and the idea of counting, while for tops there are mathematical elements in the form of tubes [17]. It can be concluded that various cultures from various regions as objects of research. There are many mathematical elements such as the concept of field geometry, transformation (reflection, translation, and rotation), points, lines, folding symmetry, rotational symmetry, acute and obtuse angles, number comparisons, relations, and congruence.
In referring to this research, innovations have emerged to conduct ethnomathematics research in the Riau Islands Province. Riau Islands has a traditional game, namely the Jong Sailboat game, which indicates a mathematical element or concept in its shape. This can be done through ethnomathematics exploration in the body of Jong Sailboats. The following are the results of the ethnomathematics exploration of the Jong Sailboat form. In the Jong Sailboat competition, the one that determines the most victory is the boat body. The Jong body's manufacture must have expertise in choosing wood and carving wood because if it doesn't fit, it will result in a defective jong Sailboat. When it is disabled, the Jong Sailboat will not sail.
Wood materials usually used are dry, lightweight, and durable wood, such as Pulai and Mentangoh wood. Pulai wood is very light and resistant to water. However, Pulai wood is quite suitable to be obtained, so if you do not have Pulai wood, Mentangoh wood is used. However, Mentangoh wood is not as light as Pulai wood.
The people around Penyengat Island, Riau Islands Province, are more dominant in using Pulai wood as jong body wood because this Pulai wood is found in many Riau Islands.

Kate
Kate serves as a counterweight to Jong's Sailboat so that Jong doesn't sink or fall. Kate is also made of Pulai wood. Kate is made smaller than Jong's body.

Ganda Kate
The Ganda Kate is a straight piece of wood that functions as a link between the kate and the kate house, located in the middle of Jong's body. Ganda kate is made of wood, which is strong and straight. Gandaa kate always follows the direction of the wind. If the wind is from the south, double kate is entered from the left. If the wind is from the north, a double kate is entered from the Jong's right.

Kate's house
Kate's house functions to tie and hold the kate as a unit of the Jong's kate and body. The kate house is made of Pulai wood. Kate's home is in the middle of the Jong's body.

Sauk
Sauk is made of Pulai wood, which is located at the front and back of the body of the Jong. Sauk serves as a barrier for the Jong's body from collisions and as a water breaker.

Sail
The sail is also very decisive for the victory at the Jong Sailboat race. The primary mover of the Jong Sailboat is the sail. The function of the sail is to change the wind rotation so that Jong Sailboat is directed. Jong's Sailboat speed depends on the sail. Usually, the material used in coastal communities for sail-making uses plastic. With the times, plastic is rarely used and is replaced by cloth and parachutes. This cloth and parachute have better resistance than plastic. The advantages of material and parachute are that they are varied in color. The color of the fabric and parachute can beautify and add to the Jong Sailboat's appearance. The screen has two parts, namely the front sail (jeep) and the rear sail.
Ethnomathematics exploration of the traditional Jong Sailboat game is carried out only in its shape. It is because, in the form of Jong Sailboat, there is a mathematical practice in it. The figure of Jong Sailboat describes a concept and mathematical skill that is applied by accident by the craftsmen or activists of Jong Sailboats. The following is the exploration of mathematical activities in the shape of the Jong Sailboat: 1. Boat Body (Jong) The jong boat parts that will be explored are the upper and lower parts of the Jong's body. Mathematical concepts are found at the top and bottom of the Jong's body, namely the idea of reflection and angle.    The concept of straight lines on the Ganda kate is used by the jong Sailboat maker to connect the kate and the Jong's body so that kate can support and secure the Jong's body when Jong's Sailboat is placed on the water through the Ganda kate so that there is a balance.

Kate's House
The kate house of Sailboat Jong has a mathematical concept, namely the rectangular concept. The idea of a rectangle is found in the holes where the double supports or kate supports.  (c) The idea of a right triangle; and (d) trigonometric concepts Figure 8a shows the image of acute and right angles; acute and right angles are found on the top and front of the jong sail. The idea of sharp angles and right angles on the front of the Jong's screen aims to connect the front screen with the mast and the Jong body so that the Jong's front sail can change the Jong's rotation when Jong Sailboat is played. Figure 8b shows the slope's concept; the idea of a pitch is found in connecting the Jong's front end, and the Jong's top pole. This tilt concept aims to keep Jong's front sail tense so that the direction of the Jong Sailboat remains consistent. Figures 8c and 8d found the concept of right triangles and trigonometry. This concept aims to calculate the significant size of the Jong's front sail so that the bottom, upright, and slanted sides are correct where the right side is more significant than the bottom side. Next is the back of the Jong Sailboat. Figure 9. Concept of Acute Angle on the Back Sail of the Jong's Sailboat The Jong Sailboat's rear sail has a mathematical concept, namely the acute angle concept. Sharp angles are found at the corners of the Sailboat Jong. The critical angle concept found on the back of the jong screen aims to connect the back sail's intersections with the mast and the Jong body.
Based on the exploration results described, several mathematical concepts and practices were found in geometric shapes in triangles, rectangles, and mathematical concepts in the way of reflections, acute angles, right angles, trigonometry, straight lines, and slopes. The shape of the Jong Sailboat contains different mathematical concepts, but there are also similar mathematical concepts. The mathematical concepts and practices found have similarities from previous studies that the researchers have described. Still, there are several different concepts: right angles, trigonometry, straight lines, and slopes. The results of this exploration can enrich ethnomathematics science, which is also found in the form of Jong Sailboats.
Educators in the learning process can use mathematical concepts and practices that have been obtained through this exploration. Educators can choose the mathematical concepts and techniques needed in learning as a learning resource. In addition to educators providing mathematics learning, educators can also introduce local culture to students by linking mathematics learners with the culture they have acquired.

CONCLUSIONS AND SUGGESTIONS
Based on the research results, it can be concluded that in the form of Jong Sailboat, there are mathematical concepts, mathematical concepts are found in almost all parts of Jong Sailboats such as the jong body, kate, Ganda kate, kate house, Sauk, and sails. In Jong Sailboat, mathematical concepts include geometric ideas in triangles, rectangles, and mathematical concepts in the form of reflections, right angles, trigonometry, straight lines, and slopes. Educators can use the results of this exploration as a source of learning mathematics at various levels of education, both in elementary and junior and high schools. In its development, it can be further explored to find the whole mathematical concept of Jong Sailboat, not only in its shape but in its entirety, such as in the making and way of playing.