The purpose of this study is to design a digital module based on mathematical communication skills. This a development research which is carried out to determine the use of poor learning media and students’ low comprehensive skills in understanding mathematical topics associated with relations and functions. One of the solutions used to overcome this problem is by designing a digital teaching module using media. The research and development method consisting of Analysis, Design, Development, implementation, and Evaluation (ADDIE), were used to carry out this study. The results showed that the digital module is highly valid with a total expert validation of 95.1% and in the very good category. Also, the students' response to the digital module is in the very good category, with a total response criterion of 89.8%. Therefore, the designed digital module has the ability to improve students' independence in learning because its use is not limited to classrooms.

This study aims to determine the feasibility of learning media in the form of videos with the help of camtasia software on number material using the R & D (Research and Development) methodology with ADDIE models (Analysis, Design, Development, Implementation, Evaluation). This research was conducted at Cirebon State MTs 2 Cirebon in class VII. The research instrument used was an interview questionnaire for teachers and students, a practicality questionnaire for students and a validation sheet for three lecturers as well as a mathematics teacher. From the results of the instruments in the form of interview questionnaires students are clear that students prefer learning with the presence of learning media and the results of teacher interviews that result in a lack of facilities for the learning process using learning media. The instrument results in the form of a validation questionnaire produce an average score of 85% (very valid), so that it can be said that the learning media in the form of videos are valid and can be used. The instrument of practicality questionnaire filled by nine students with three high-ability students, three moderate-capable students, three low-ability students produced an average score of 86.77%, it can be said that the practice was very high. Based on the results of each instrument, it can be stated that the learning media in the form of CD-shaped videos is practical and can be used.

Waste collection and transportation processes are accounted for more than 50% of all total waste management costs then there is an urgency for a waste recycling company to minimize this activities-related total cost by any means. Route optimization in collecting those plastics wastes can be a good solution to addressing the problem. This research focuses on determining waste collection routes for multilayer plastic with the objective function of minimizing total transportation costs. The waste collection problem is modeled as Vehicle Routing Problem (VRP) with a certain capacity and constrained time windows but here the vehicle is allowed to travel multiple times, this model said as the Multi-Trip Multi-period Capacitated Vehicle Routing Problem with Time Windows (MCVRPTW). The model was solved by an exact method using mixed integer linear programming and a metaheuristic approach using the Genetic Algorithm (GA). The results showed that the exact method was able to solve problems on small data instances and required almost 100% higher computation time than of metaheuristic approach. The best GA solution with mutation and crossover rates of 0.75 and 0.1 provides savings of 30.2% compared to the total transportation cost for existing conditions.

Guru dapat meningkatkan prestasi kerja kependidikannya, yaitu kualitas anak didik, baik dari segi psikis maupun mental spiritual. Tujuannya, ialah: (1) Meningkatkan pengetahuan/pemahaman kepada guru PAUD mengenai alat peraga, manfaat, tujuan, dan kegunaan alat peraga; (2) Memperkenalkan bentuk dan  pembuatan alat peraga kepada guru PAUD untuk menambah wawasan dan keterampilan; dan (3) Menanamkan sikap profesionalitas dalam mengajar peserta didik terkait pedagogic knowledge. Kegiatan ini dilaksanakan pelatihan pembuatan alat peraga digital untuk menunjang kompetensi pedagogik dalam rangka meningkatkan keprofesionalan guru. Hasilnya, kegiatan penyuluhan dan pelatihan ini sangat bermanfaat bagi semua peserta; 96,2% peserta memahami pemaparan materi; dan 92,3% peserta telah mampu mengaplikasikan alat peraga digital.

The virus that causes COVID-19, SARS-CoV-2 continues to undergo mutations forming new variants. The latest variant that has been detected, namely the Omicron variant known as the B.1.1.529 variant.  The Omicron variant has a high transmission rate of up to 5 times that of the previous variant including the Delta variant. The speed of transmission that occurs in South Africa is still being carried out epidemiological studies to find out whether this is caused by Omicron or other factors. Transmission is easier to occur in individuals who have not received the vaccine and this can also cause complications in their treatment. Nonetheless, some countries are concerned about pressure on health systems due to the increased need for hospitalizations as the rate of transmission of this variant is much higher. Viral replication occurs 70 times faster in the respiratory tract, but 10 times slower when in human lung tissue.  Because one of the efforts that can be done to avoid Covid-19 is to use a vaccine, it can help protect people around from the corona virus. Especially people who are at high risk of severe illness from COVID-19. By seeing these problems, it is necessary to have health counseling in getting to know the new variant of Covid-19 (omicron) and increasing public awareness of how important Covid-19 vaccination is