Fundamental Aspects, Mechanical Behaviour and Mathematical Understanding of Friction Spot Stir Welds: A Review

The energy-saving and environmental conservation are increasingly important issues in manufacturing and service industries worldwide that have received considerable attention in recent years. Most importantly, this process eliminates the grain solidification errors generated by the standard fusion process. Thus, in this papers types and methods of stir welding will be explained and discussed accordingly . Friction stir spot welding is a tunable method as it allows an effective control and amendment of processing parameters using refill and powder-assisted schemes that can solve the problem of the keyhole and mechanical weaknesses in the joining of light metals processed by conventional Friction stir spot welding. This comprehensive review mainly focuses on the fundamental aspects of Friction stir spot welding processes and their impacts on the microstructural features and mechanical performance and mathematical understanding of various similar and dissimilar systems. To conclude, the challenges in further modification of Friction stir spot welding and future outlooks in different engineering applications are presented.

The improvement of mathematics understanding ability on system of linear equation materials and students learning motivation using geogebra-based educational games

The purpose of this research is to determine the improvement of students' mathematical understanding ability on a system of linear equations using GeoGebra-based game education. This research use quasi-experimental that was conducted on two classes of the school in Indonesia. Class X MIPA 4 as experimental class and X MIPA 3 as control class. Based on the results the average score of N-Gain value analysis, mathematical concept understanding ability in the experimental class is 0.55, and the control class average score is 0.30. Based on the calculation, the Asymp. Sig. (2 tailed) of 0.000 is obtained. Because the significance score is obtained less than 0.05, thus it is rejected and is accepted. So, it can be concluded that the improvement of students' mathematical understanding ability using GeoGebra-based game education is better than the improvement through ordinary learning. The learning motivation of students using GeoGebra-based game education as a positive learning media, but there is no relationship between learning motivation and students' mathematical understanding using GeoGebra-Based Game Education.

DEVELOPMENT OF QUR'AN AND HADITH-BASED MATHEMATICS MODULE FOR STUDENTS' MATHEMATICAL UNDERSTANDING AND RELIGIOUS CHARACTER

The module is a means of delivering material to students and a supporting tool in the learning process. The teaching materials used are also expected to be able to build the values ​​and morality of each student through learning the integration of science and religion, one of which is by using teaching materials based on the Qur'an and Hadith. This study aims to develop teaching materials in mathematics learning in the form of modules based on the Qur'an and Hadith. This type of research is research and development using the Borg & Gall development model. The development of the module is carried out on the fractional number material for class VII Islamic Junior High School (MTs). The data collection instruments used in this study were a questionnaire from media experts, material experts, and religious experts who were used to test the quality of the mathematics module based on the Qur'an and Hadith, as well as a questionnaire response from educators and students who were used to test interest in the developed module. Data collection methods used in this study are interviews, documentation, and questionnaires. This research produces a product in the form of a mathematical module based on the Qur'an and Hadith. In learning using a mathematics module based on the Qur'an and Hadith in grade VII Takhasus MTs Hidayatul Mubtadiin Dayamurni can improve students' mathematical understanding at a moderate level. Learning using a mathematics module based on the Qur'an and Hadith can shape students' religious attitudes.

The Emergence of Mathematical Understanding: Connecting to the Closest Superordinate and Convertible Concepts

This study aimed to examine the specific means and internal processes through which mathematical understanding is achieved by focusing on the process of understanding three new mathematical concepts. For this purpose interviews were conducted with 54 junior high school students. The results revealed that mathematical understanding can be achieved when new concepts are connected to at least two existing concepts within a student’s cognitive structure of. One of these two concepts should be the superordinate concept of the new concept or, more accurately, the superordinate concept that is closest to the new concept. The other concept should be convertible, so that a specific example can be derived by changing or transforming its examples. Moreover, the process of understanding a new concept was found to involve two processes, namely, “going” and “coming.” “Going” refers to the process by which a connection is established between a new concept and its closest superordinate concept. In contrast, “coming” is a process by which a connection is established between an existing convertible concept and a new concept. Therefore the connection leading to understanding should include two types of connections: belonging and transforming. These new findings enrich the literature on mathematical understanding and encourage further exploration. The findings suggest that, in order to help students fully understand new mathematical concepts, teachers should first explain the definition of a given concept to students and subsequently teach them how to create a specific example based on examples of an existing concept.

EFFECT OF SKINNER'S LEARNING THEORY WITH PICTURE AND PICTURE MODEL ON THE ABILITY OF MATHEMATICAL UNDERSTANDING OF STUDENTS IBNU HAJAR MANDIRI

Mathematics is often considered a scourge for the field of study that is considered difficult and boring, the learning carried out is teacher-centered where students are less active and only accept the learning delivered by the teacher. Based on this background, the purpose of this research is to find out the improvement of students' mathematical understanding skills whose learning uses Skinner's learning theory through picture and picture models, to find out the differences in students' mathematical understanding abilities who use Skinner's learning theory through picture and picture models with those who do not use Skinner's learning theory but through the picture and picture model, and knowing the student's response to learning using Skinner's learning theory through the picture and picture model. The research method used is a true experimental method with a population of all eighth-grade students of Ibnu Hajar Mandiri Bekasi Junior High School for the 2020/2021 academic year. Sampling was done purposively. The instrument is a test about the description of students' mathematical understanding abilities on function material and questionnaire sheets. The results showed that learning mathematics using Skinner's learning theory through picture and picture models can improve students' mathematical understanding skills, besides that there are differences in the mathematical understanding of students whose learning uses Skinner's learning theory through picture and picture models with students whose learning does not use Skinner's learning theory but through picture and picture models. The student's response after using Skinner's learning theory through the picture and picture model was considered good. This shows that only a small number of students still consider mathematics a very difficult and boring subject.

PROFIL PEMAHAMAN MATEMATIS SISWA DALAM MENYELESAIKAN MASALAH BERDASARKAN KEMAMPUAN MATEMATIKA DI SMK MUHAMMADIYAH 1 BARON

Mathematics has a special characteristic that is an abstract object of study. Because of this specificity, learning mathematics requires mathematical understanding. Mathematical understanding in solving mathematical problems is different between each student. This difference is because each student has different mathematical abilities. The purpose of this study was to describe (1) the profile of mathematical understanding of students with high mathematics ability in solving problems (2) the profile of mathematical understanding of students with moderate mathematics ability in solving problems (3) the profile of mathematical understanding of students with low mathematics ability in solving problems. This research is a qualitative descriptive study with 3 students as the subject of class XI SMK Muhammadiyah 1 Baron. The selection of research subjects was based on students' mathematical abilities, namely high, medium and low mathematical abilities. Data collection techniques in this study using problem solving test techniques and interviews. The validity of the data used in this study used time triangulation. Based on the results of data analysis, the results showed that (1) The profile of mathematical understanding with high mathematical ability in solving quadratic function problems is the subject of reading the problem until it understands, writing correctly what is known and asked, conducting problem exploration appropriately, choosing the right problem solving strategy, looking for answers by doing algebraic calculations correctly and checking the answers back from the solutions obtained. (2) The profile of mathematical understanding with moderate mathematical ability in solving quadratic function problems is that the subject reads the problem until he understands, correctly states what is known and asked, skips problem exploration, looks for answers by doing algebraic calculations even though inaccurate answers are obtained and does not check answer back. (3) The profile of mathematical understanding with low mathematical ability in solving quadratic function problems is that the subject reads the problem until he understands, correctly states what is known and asked, skips problem exploration, looks for answers by doing algebraic calculations but gets inaccurate answers and does not check answer back. ABSTRAKMatematika memiliki karakteristik khusus yaitu objek kajian yang abstrak. Karena kekhususannya ini maka dalam mempelajari matematika diperlukan pemahaman matematis. Pemahaman matematis dalam menyelesaikan masalah matematika berbeda antar setiap siswa. Perbedaan ini dikarenakan setiap siswa memiliki kemampuan matematika yang berbeda. Tujuan penelitian ini adalah untuk mendeskripsikan (1) profil pemahaman matematis siswa berkemampuan matematika tinggi dalam menyelesaikan masalah (2) profil pemahaman matematis siswa berkemampuan matematika sedang dalam menyelesaikan masalah (3) profil pemahaman matematis siswa berkemampuan matematika rendah dalam menyelesaikan masalah. Penelitian ini merupakan penelitian deskriptif kualitatif dengan subjek penelitian kelas XI SMK Muhammadiyah 1 Baron berjumlah 3 siswa. Pemilihan subjek penelitian berdasarkan pada kemampuan matematika siswa yaitu kemampuan matematika tinggi, sedang dan rendah. Teknik pengumpulan data dalam penelitian ini menggunkan teknik tes pemecahan masalah dan wawancara. Keabsahan data yang digunakan dalam penelitian ini menggunakan triangulasi waktu. Berdasarkan hasil analisis data diperoleh hasil bahwa (1) Profil pemahaman matematis berkemampuan matematika tinggi dalam menyelesaikan masalah fungsi kuadrat adalah subjek membaca masalah sampai paham, menuliskan dengan benar apa yang diketahui dan ditanyakan, melakukan eksplorasi masalah dengan tepat, memilih strategi penyelesaian masalah dengan tepat, menacari jawaban dengan melalukan perhitungan aljabar dengan tepat serta melakukan pemeriksaan jawaban kembali dari solusi yang diperoleh. (2) Profil pemahaman matematis berkemampuan matematika sedang dalam menyelesaikan masalah fungsi kuadrat adalah subjek membaca masalah sampai paham, menyebutkan dengan benar apa yang diketahui dan ditanyakan, melewatkan eksplorasi masalah, menacari jawaban dengan melalukan perhitungan aljabar walaupun diperoleh jawaban yang kurang tepat serta tidak melakukan pemeriksaan jawaban kembali. (3) Profil pemahaman matematis berkemampuan matematika rendah dalam menyelesaikan masalah fungsi kuadrat adalah subjek membaca masalah sampai paham, menyebutkan dengan benar apa yang diketahui dan ditanyakan, melewatkan eksplorasi masalah, menacari jawaban dengan melalukan perhitungan aljabar namun diperoleh jawaban yang kurang tepat serta tidak melakukan pengecekan jawaban kembali.

ANALISIS KEMAMPUAN PEMAHAMAN KONSEP MATEMATIKA PADA KELAS XI BUDAYA DI SMAK St. FRANSISKUS ASISI LARANTUKA

The purpose of this study is to determine the ability to understand the mathematical concept of students of class XI Culture SMAK St. Francis of Assisi Larantuka. The data are collected by the results of students’ ability test in understanding of mathematical concepts and unstructured interviews. The test questions used to measure students’ abilities in understanding mathematical concepts consist of 2 questions in the form of descriptions with matrix transpose material and matrix multiplication. The test results are analysed based on indicators of mathematical understanding, namely: 1) the ability to explain a definition in their own words according to essential traits/characteristics, 2) the ability to make examples in mathematical concepts, 3) the ability to use concepts in solving problems. Population in this study are students on eleventh culture class of SMAK St. Francis of Assisi Larantuka with two sample of students. The results show that there are the differences in the ability to understand mathematical concepts between students through Problem Based Learning.Keywords: Mathematical concepts understanding, Problem Based Learning, matrix.

Game Based Intervention to Develop Early Childhood Mathematical Understanding and Decrease Gaps Related to Socioeconomic Status

Early mathematical understanding is important for later success in mathematics. Game based interventions can be a successful means by which to help young students to improve their mathematical understandings. The purpose of this study is to examine whether a math game that was to be played at home improved the mathematical understanding of kindergarten students. Kindergarten students, from rural Idaho, were assigned to a group that played math games (n = 15) or a control group that did not (n = 13). The intervention group was given a simple math game and instructed to play 20 times in a 2 week period. The control group played a sight word game with the same instructions for frequency. Results showed that playing the game at home did not improve performance on the math assessment. A survey was also used to gather information about whether or not reported amounts of game playing at home would be correlated to higher scores on a mathematics assessment. Results showed that reported game playing at home was not related to higher scores on a mathematics assessment.

THE INFLUENCE OF CONTEXTUAL TEACHING AND LEARNING APPROACH AND STUDENTS’ GENDER ON MATHEMATICS UNDERSTANDING AT GRADE IV SDN ALANG LAWAS, PADANG

The purpose of this study was to describe differences in the understanding of students who learned through CTL approach and students who learned through the conventional approach, to observe the differences in the Mathematics understanding of male students and female students, and to see the interaction between the learning approach and gender on the mathematics understanding. The type of this research was a Quasi Experimental Design with a factorial design (2x2 factorial design). The population in this study was all fourth grade students at SDN Alang Lawas Padang. The samples were students at SDN 37 Alang Lawas as the control class and students at SDN 20 Alang lawas as the experimental class. The results of the research concluded that (1) there were differences in the mathematical understanding of students who were taught by CTL approach and the students who were taught by a conventional approach; (2) there were differences in the mathematical understanding of male students and female students at grade IV SDN Alang Lawas; and (3) there was no significant interaction between learning approaches and gender in influencing students' mathematical understanding.