Abstract
The demand for aluminum in various fields continuously grows, including in the automotive industry. In this industry, aluminum is used as the material for the spare part. Therefore, aluminum ...with high mechanical properties and low casting defects is required. One of the available alternatives for producing excellent aluminum is through aluminum casting, including die casting. Die casting offers low cost in mass manufacturing of complex shaped components with acceptable casting results. Further, the selection of die-casting parameters and the addition of reinforcing elements can also improve the mechanical properties of aluminum. In this study, we strengthened the Al-Si matrix using High Pressure Die Casting process with particles from snail shell powder (calcium carbonate). Further, this study also explores the mechanical properties and microstructure of the product produced through experiment and optimization. The optimization was adopted to identify the optimum parameter. For the optimization, we used the Taguchi method. Our analysis results suggested that the reinforcing agent from the snail shell powder has the CaO and Ca(OH)
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phases, with a crystallite size of 106.59 nm. The morphology of the shell powder reinforcing agent showed the presence of agglomeration and interconnected structures, such as skeletons, with average particle size of 0.4 micro. The functional group of the shell powder reinforcing agent showed the OH band during the water absorption by CaO, along with asymmetric C–O with vibration from the carbonate group and Ca–O bound. The most excellent hardness level was identified from T8, with 86.33 HRB and die casting parameters of 0.15% reinforce agents, 750 °C temperature injection, and 50 MPa pressure. Meanwhile, the best tensile strength was found from the T9 sample, with 109,95 MPa and die casting parameters of 0.15% reinforce agents, 800 °C temperature injection, and 60 MPa pressure. Microstructure on the used piston die casting sample with snail shell powder reinforcing agent showed the presence of Al, Si, dendrite, and Al
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Ca phases. The multiple response analysis on the three factors indicated that the reinforcing agent presented the most significant effects toward the tensile strength and hardness, followed by pressure and temperature injection. Meanwhile, the Taguchi method and ANOVA results showed the optimal parameter die casting was obtained from a combination of 0.15 wt% reinforce agent, 800 °C injection temperature, and 50 MPa pressure. A multiple linear regression mathematical model for tensile strength and hardness was developed from the observed data. In regression model, the value of R
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of tensile strength 74.02% and R
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of the hardness is 95,18% Thus, the developed model can be effectively used to predict the tensile strength and hardness
Substitution of wheat flour with other ingredients in food processing is currently being considered for developing healthy food products. Purple Sweet Potato flour is one option that can be used as a ...substitute for wheat flour. In this study, cookies were made with purple sweet potato flour as a substitute. This study aims to determine the best formulation and analyze the proximate and hedonic characteristics to determine consumer acceptance of purple sweet potato cookies through sensory tests. This research is a completely randomized design experiment. treatment is the ratio of the amount of wheat flour and purple sweet potato flour in the processing of pastries. The parameters tested were moisture content, ash, protein, fat, crude fiber, carbohydrates, and organoleptic (taste, aroma, color, and texture). The results of the proximate analysis illustrate that, compared with control cookies, cookies substituted with purple sweet potato had higher carbohydrate, ash, fiber, and water content, while the fat and protein content became lower. Purple sweet potato flour can substitute up to 100% wheat flour, but based on research results, most of the panelists didn't like the taste. Most of the panelists liked the taste, aroma, and texture of cookies with a concentration of 25% purple sweet potato flour substitution compared to wheat flour. Based on the color parameters, most of the panelists liked cookies with a purple sweet potato flour substitution concentration of 50%.
Sekolah Menengah Kejuruan (SMK) merupakan salah satu sekolah yang memiliki potensi resiko bahaya kerja lebih tinggi dibandingkan jenis sekolah yang lain. Hal ini diibaratkan bahwa SMK merupakan salah ...satu wujud pabrik sekolah dimana di dalamnya terdapat laboratorium, bengkel maupun workshop untuk aktivitas praktik siswa. Adapun potensi resiko bahaya yang terdapat di SMK salah satunya yaitu faktor ergonomi. Faktor ergonomi berkaitan dengan kebiasaan kerja oleh masing-masing individu. Oleh karenanya seluruh SDM di SMK sudah seharusnya memiliki pemahaman terkait ergonomi yang benar. Sehingga para SDM di SMK dapat menerapkannya secara tepat. Penelitian ini bertujuan untuk 1) mengetahui pemahaman guru terkait dampak Covid-19 pada pendidikan di SMK, 2) mengetahui pemahaman guru terkait budaya belajar ergonomis untuk pencegahan Covid-19. Penelitian ini merupakan penelitian deskriptif kualitatif. Sumber data penelitian yaitu guru SMK di Malang berjumlah 25 orang. Pengumpulan data menggunakan wawancara dan dokumentasi. Berdasarkan analisis data diperoleh kesimpulan bahwa 1) secara garis besar guru memiliki pemahaman terkait dampak Covid-19 bagi pendidikan di SMK yang sangat berpengaruh pada tatanan sistem pembelajaran pada berbagai aspek, 2) guru memiliki pemahaman yang cukup terkait budaya belajar ergonomis untuk pencegahan Covid-19, namun masih diperlukan tindak lanjut secara nyata agar penerapan budaya belajar ergonomis lebih maksimal.
Berbagai model pembelajaran berbasis digital berkembang seiring dengan perkembangan teknologi. Terutama pasca pandemi, reformasi pembelajaran berbasis digital berkembang sangat pesat. Dunia ...pendidikan berlomba-lomba memanfaatkan teknologi komputer sebagai basis teknologi multimedia dalam pengembangan model media pembelajaran. Tanpa terkecuali pada tataran pendidikan tinggi seperti universitas. Universitas Negeri Malang (UM) menjadi salah satu universitas yang senantiasa terus mengembangkan media pembelajaran yang mampu menunjang pembelajaran pada abad 21 yang tidak terbatas ruang dan waktu. Salah satu program studi di UM yang perlu pengembangan media pembelajaran sebagai sarana penunjang pembelajaran yaitu D4 Teknologi Rekayasa Manufaktur. Penggunaan sumber belajar pada perkuliahan elemen mesin pada program studi D4 Teknologi Rekayasa Manufaktur sangat terasa urgensinya karena sejauh ini pada prodi D4 belum banyak sumber belajar multimedia interaktif yang digunakan Penelitian ini bertujuan untuk mengetahui peran aplikasi MEA dalam pelaksanaan pembelajaran mata kuliah elemen mesin. Penelitian ini merupakan penelitian deskriptif kuantitatif. Populasi dari penelitian ini yaitu mahasiswa D4 Teknologi Rekayasa Manufaktur Universitas Negeri Malang semester 1 pada tahun pembelajaran 2023/2024. Instrumen yang digunakan yaitu kuesioner dengan skala likert. Uji coba istrumen menggunakan uji validitas dan reliabilitas. Analisis data menggunakan analisis statistik deskriptif menggunakan SPSS. Berdasarkan hasil analisis diperoleh 5 kesimpulan. Pertama, kemudahan akses aplikasi MEA sebesar 78,6%. Kedua, kemudahan penggunaan aplikasi MEA untuk proses pembelajaran elemen mesin sebesar 82,1%. Ketiga, peran aplikasi MEA dalam membantu proses pembelajaran elemen mesin sebesar 75%. Keempat, kesesuaian teknologi penerapan MEA untuk pembelajaran jarak jauh pada mata kuliah elemen mesin sebesar 89,3%. Kelima, peran aplikasi MEA terhadap peningkatan hasil pembelajaran elemen mesin sebesar 82,1%. Sehingga secara garis besar aplikasi MEA memiliki peran yang sangat baik sebagai mobile learning interaktif untuk optimasi pembelajaran digital pada pendidikan vokasi.
The major factors determining the quality of sand casting products are the base sand and the composition of the sand mould and the binding material. In the foundry industry, the most commonly used ...binder for creating sand moulds is bentonite. However, the price of bentonite is likely to keep rising. This study aimed at discovering a new binder formula associated with the effect of binder composition i.e. bentonite, tapioca flour, and sago flour on the basis of its mechanical and physical properties. The new formula was expected to be a better binder in the production of sand moulds, resulting in high-quality casting products with minimal defects. Moreover, it is probable to be much more economical than bentonite. This research focused on testing the moulding sand composition with a number of different binders, i.e. bentonite, tapioca flour, and sago flour, each in a different proportion. The mixture of the moulding sand with each of the three binders will be tested in terms of its mechanical properties including compressive, shear, and tensile strength. Based on the test results, sago flour has the highest dry compressive strength of 28.6 N/cm2, whereas bentonite has the highest wet compressive strength, i.e. 11.83 N/cm2 and the highest wet shear strength i.e. 3.16 N/cm2. The binder with the highest dry shear strength is tapioca flour with 18.16 N/cm2. Regarding the tensile strength value, bentonite has the highest wet tensile strength of 0.85 N/cm2, while sago flour has the highest dry tensile strength of 1.73 N/cm2.
The digital era has accelerated the development of educational media. This enables access to educational activities from any location at any time. Distance education is gaining popularity and ...flexibility in its implementation. The purpose of this study is to determine the role of MEA applications in machine element learning, specifically in the State University of Malang's D3 Mechanical Engineering Study Program. MEA is an interactive mobile learning platform designed to broaden D3 students' access to sources and learning tools. This is a quantitative descriptive study. The population of this study consisted of 40 students enrolled in D3 Mechanical Engineering at the State University of Malang. The data were gathered through literacy assessments, observations, interviews, and questionnaires. The tool is a questionnaire constructed on the basis of the Likert scale. Instrument testing included validity and reliability checks. The data analysis technique was descriptive analysis. Five conclusions have been drawn as a result of the analysis. First, the MEA application is 78.6% user-friendly. Second, the MEA application is easy to use for the machine element learning process in 82.1% of cases. Third, the MEA application assists the machine element learning process by 75%. Fourth, 89.3% of MEA application technology is suitable for distant education in the machine element course. Fifth, MEA applications improve machine element learning outcomes by 82.1%.
Water is one of the indispensable human necessities. The majority of daily activities require water. Along with population growth and changes in people's lifestyles, the need for clean water grows ...daily. The people who live in Bulupitu village in Gondanglegi likewise recognize the importance of having access to clean water. Due to financial constraints, there are still a significant number of residents who lack access to local water company (PDAM). Therefore, the majority of people continue to rely on groundwater and river water. To maximize the use of water, therefore, a non-electrical gravity-based water pump technology is necessary. This pump operates without electricity, making it more cost-effective. This activity is implemented through surveys, discussions with partners, analysis of problems and needs, counseling regarding clean water, the development of water pump, evaluation, and monitoring. On the basis of an analysis of the needs and quantity of water required by the residents of Bulupitu, the acquisition of non-electric pumps can increase the total water supply by 7%. This is based on the estimation that each person requires 250 liters of water per day, given the total population of 3000. In order for the total water requirements of all residents to reach 750.000 liters. As a matter of fact, 24-hour pumps can produce between 47000- 52000 liters of water.
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