Corrugated cardboard has multilayer construction that produces rigid, durable, and worthy material for shipping heavy goods or hazmat. The numerous advantages offered have made it a worldwide staple ...in the warehousing, packaging, and transportation industries. Unfortunately, studies on corrugated cardboard’s mechanical properties and behavior are still limited due to the complexity of structures and testing procedures. The present work investigates corrugated cardboard’s mechanical properties and behavior by conducting uniaxial tensile and compressive tests. Three different testing directions in x, y, and z-axes were applied on AA-flute double-wall (AA/F-DW) or virgin pulp paper Bi-Wall corrugated cardboard. The stress-strain curve is measured and evaluated to obtain the mechanical properties, i.e., yield strength and ultimate strength. The result shows that corrugated cardboard has linear and non-linear mechanical behavior or elastic-plastic regions under those different directions. Moreover, the flute on the corrugated cardboard gives jaggedness to the stress-strain curve and makes the material more elastic, more durable, and has better absorbing energy capacity. This finding could be used to design any products, such as a packaging frame made of corrugated cardboard, where the strength of the structure could be predicted based on the mechanical properties and behavior.
The increasing seismic activity of Arjuno Welirang on February 7, 2018, warned about the dangers of volcanic eruptions that must be watched out for, so that activity needs to be monitored ...continuously. There is little information available about seismic activity at the Arjuno Welirang complex. Most studies have investigated geothermal potential and subsurface structures. Due to the limitations of this data, land surface temperature (LST) analysis was carried out in this research to monitor the development of Arjuno-Welirang volcanic activity. Several volcano studies have used LST criteria in remote sensing applications to detect volcanic activity. However, the performance of LST has not been tested in the case of normal volcanic activity, which is influenced by external thermal disturbances. This study aims to show the performance of LST detection on changes in the normal volcanic activity of Arjuno Welirang, which is disturbed by temperature noise caused by the El Niño phenomenon. The LST calculations are carried out by including surface emissivity corrections obtained based on Normalized Difference Vegetation Index (NDVI) values. The LST calculation algorithm is implemented with the Google Earth Engine (GEE) platform. LST analysis was carried out on Landsat 8 images for the May-August 2023 time period obtained from the United States Geological Survey (USGS) database via GEE cloud computing. The reason for determining this time period is because the release of the daily Arjuno Welirang volcanic activity report by Magma Indonesia coincided with the Meteorology Climatology and Geophysical Agency (BMKG) notification regarding the occurrence of El Niño phenomenon. The output is an LST curve against time, which shows a tendency for the surface temperature of the Arjuno-Welirang crater to increase in July. This is similar to the trend of increasing seismic activity reported on the Magma Indonesia website and conversely is not similar to the increase in temperature due to the El Niño effect predicted by BMKG. The highest temperature increase occurred on July 24 2023, reaching 31.78 ⁰C, and then the temperature decreased. The method used in this research has proven that LST analysis is able to detect changes in normal volcanic activity in the Arjuno-Welirang crater even though there is thermal noise due to the influence of the impact of El Niño. LST values are more dominantly influenced by volcanic activity than by extreme El Niño weather.
In the last decades of electric vehicle (EV) development, battery thermal management has become one of the remaining issues that must be appropriately handled to ensure robust EV design. Starting ...from researching safer and more durable battery cells that can resist thermal exposure, battery packing design has also become important to avoid thermal events causing an explosion or at least to prevent fatal loss if the explosion occurs. An optimal battery packing design can maintain the battery cell temperature at the most favorable range, i.e., 25–40 °C, with a temperature difference in each battery cell of 5 °C at the maximum, which is considered the best working temperature. The design must also consider environmental temperature and humidity effects. Many design strategies have been reported, including novel battery pack constructions, a better selection of coolant materials, and a robust battery management system. However, those endeavors are faced with the main challenges in terms of design constraints that must be fulfilled, such as material and manufacturing costs, limited available battery space and weight, and low energy consumption requirements. This work reviewed and analyzed the recent progress and current state-of-the-art in designing battery packs for superior thermal management. The narration focused on significant findings that have solved the battery thermal management design problem as well as the remaining issues and opportunities to obtain more reliable and enduring batteries for EVs. Furthermore, some recommendations for future research topics supporting the advancement of battery thermal management design were also discussed.
Based on Regional Agency for Disaster Management (BPBD) Batu City data, Indonesia, 36 landslides have been recorded in the last three years around the Payung area, where this area connects several ...regions around Batu City. So, it is necessary to map areas with potential ground movement as an initial step for the local government in formulating a landslide disaster management strategy. This research aims to map landslide susceptibility areas around Payung, Batu City, identified based on the soil vulnerability index value range in the peak ground acceleration (PGA) mapping results. The data was measured using the microtremor method. There were 22 measurement points in 3 zones with different heights, and the microtremor signal was recorded for 35-40 minutes at each point. The microtremor signal from seismic recording is composed of three components (NS, EW, and Up-Down), which are used to develop the Horizontal to Vertical Spectral Ratio (HVSR) technique, where the ratio value is obtained by comparing horizontal (H) components (HNS and HEW) to the vertical component (Up-Down (V)). The research results show that landslide susceptibility areas are located at points M10, M13, and M16, with a soil vulnerability index range of 21-40.1. When a landslide occurs in that area with high vulnerability, it will impact points along Payung Street at points M3–M9. The points with high soil vulnerability index values need special treatment to reduce the impact of landslides.
Learning inovation needed to prepare the next generation to compety in twenty first century. Learning trend nowdays is integrating the ability of scientists and engineers to develop technology. One ...of goverment effort is determine basic competence. Students need understand the electromagnetic as basic technology development, espcially faraday induction in faraday flshlight. The aim of this paper to describe the gap between real condition, the characteristic of electromagnetic material and basic competence. This paper give solution by lesson plan. Data collected by survey. The result showed that electromagnetic learning still unreach the basic competence because less of engagement between students, learning media and time constraint. Students wish for the next learning can engage technology and project. Learning inovation which appropiate to solve this gap is project based learning (PjBL) based science, technology, engineering and mathematic (STEM).Abstrak: Inovasi pembelajaran dibutuhkan untuk mempersiapkan generasi siap saing di abad 21. Tren pembelajaran saat ini mengintegrasikan kemampuan saintis dan engineer dalam mengembangkan teknologi. Salah satu upaya pemerintah menentukan kompetensi dasar. Elektromagnetik sebagai basis perkembangan teknologi perlu dipahami siswa, salah satunya senter faraday. Artikel ini bertujuan mendeskripsikan kesenjangan antara kondisi nyata, karakteristik materi dan tuntutan KD. Disajikan inovasi solusi dalam bentuk rancangan pembelajaran. Data dikumpulkan melalui survei. Hasil penelitian menunjukkan pembelajaran elektromagnetik belum mencapai KD karena kurang melibatkan antar siswa maupun media pembelajaran dan kendala waktu. Siswa berharap pembelajaran melibatkan teknologi dan proyek. Inovasi pembelajaran yang sesuai adalah PjBL berbasis STEM.
Lake Limboto is one of the major lakes in Sulawesi, Indonesia. It is currently undergoing serious degradation due to population pressure. As more residential areas have been established around the ...lake, the sedimentation rate has increased because of the contribution of anthropogenic particles. In this study, the lithogenic and anthropogenic components in surface sediments from 17 points in the lake were studied and identified using a combination of magnetic and geochemical analyses. The results showed that although the magnetic susceptibility values in R (residential) and NR (non-residential) areas were relatively similar, the values of saturation isothermal remanent magnetization (SIRM) as well as those of SIRM/χLF differed significantly, implying that the magnetic characteristics of the lithogenic component (in the NR area) differ from those of the anthropogenic component (in the R area). The discrepancy between the anthropogenic and lithogenic contributions was further supported by trace metals and rare earth element (REE) contents. Sediment samples in the R area contained higher levels of Mn, La, Pr, and Gd, while in the NR area they contained higher levels of Fe, Sc, Nd, and Ce. The magnetic susceptibility also correlated strongly with Fe, Cu, Zn, and Mn contents in the NR area. A similar correlation was not observed in the R area. The results above imply that a combination of magnetic and geochemical analyses can successfully differentiate lithogenic and anthropogenic components or contributions in lake sediments.
The purpose of this study was to analysed conceptual understanding and difficulties (misconceptions) of students in the kinetic theory of gases. Test consisted of 9 reasoned multiple choice questions ...administered after students study the material. From the results of the study, students get an average score of 7.1 from maximum score of 9. Students have mastered the concept of the relationship between ideal gas state quantities (pressure, volume, temperature) and kinetic energy of ideal gases. However, students still have difficulty in determining internal energy if the number of particles changing, the average speed of ideal gases, and the application of ideal gas law to the circulatory phenomena in the heart.Abstrak: Penelitian ini bertujuan untuk menganalisis penguasaan konsep dan kesulitan (miskonsepsi) siswa pada materi teori kinetik gas. Soal tes terdiri dari sembilan soal pilihan ganda beralasan yang diberikan setelah siswa mempelajari materi tersebut. Dari hasil penelitian, siswa mendapatkan skor rata-rata 7,1 dari skor maksimal 9. Siswa telah menguasai konsep hubungan antar besaran keadaan gas ideal (tekanan, volume, suhu) dan energi kinetic gas ideal. Namun, siswa masih mengalami kesulitan dalam menentukan energi internal dengan jumlah partikel gas yang berubah, kelajuan rata-rata gas ideal, dan aplikasi persamaan keadaan gas pada fenomena peredaran darah di jantung.
Sifat mineral magnetik pada sedimen bergantung pada batuan dan juga lingkungan pembentuknya. Sensifitas mineral magnetik terhadap lingkungan pembentuknya menjadi proxy indicator untuk mengetahui ...proses lingkungan pembentuknya baik yang dipengaruhi oleh proses alamiah atau litogenik maupun karena komponen antropogenik. Hal ini sangat membantu dalam menginvestigasi sumber mineral magnetik pada sedimen sungai sehingga dapat diketahui proses perubahan lingkungan yang terjadi di perairan sungai. Dalam metode kemagnetan batuan salah satu parameter yang lazim dimanfaatkan untuk menginvestigasi sumber mineral magnetik pada batuan dan sedimen yaitu parameter suseptibilitas magnetik. Untuk itu studi ini bertujuan untuk menginvestasi sumber mineral magnetik pada sedimen Sungai Biyonga sebagai salah satu inlet Danau Limboto. Danau Limboto merupakan salah satu dari 15 danau di Indonesia yang terdegradasi dan perlu upaya untuk menelusuri kontribusi sedimen sungai yang dikontrol oleh komponen litogenik dan antropogenik. Sampel sedimen sungai diambil pada enam titik dengan memperhatikan lingkungan di sekitar Sungai Biyonga. Hasil pengukuran menunjukkan bahwa nilai suseptibilitas magnetik frekuensi rendah (χLF) berkisar dari 130,18 x 10-8 m3/kg hingga 165,00 x 10-8 m3/kg. Konsentrasi mineral magnetik pada sampel ini cenderung dipengaruhi oleh mineral ferimagnetik kelompok Besi-titanium oksida yaitu magnetit (Fe3O4) dan Hematite (Fe2O3). Namun berdasarkan nilai χFD% mineral magnetik pada sampel cenderung didominasi oleh mineral non superparamagnetik berbulir kasar (>0,03 µm) dengan domain stable single domain (SSD) dan multidomain (MD) yang merupakan tipikal dari mineral magnetik yang bersumber dari komponen antropogenik. Bahkan hal ini didukung dengan analisis morfologi mineral magnetik yang menggunakan citra SEM yang menemukan adanya bentuk bulat bulir mineral magnetik. Karakter mineral magnetik ini mencirikan mineral magnetik yang mengalami proses oksidasi akibat kehadiran material antropogenik pada sedimen Sungai Biyonga yang berasal dari komponen antropoenik. Parameter suseptibilitas magnetik ternyata telah berhasil membuktikan bahwa terdapat sedimen Sungai Biyonga yang masuk ke Danau Limboto yang cenderung berasal dari komponen antropogenik terutama dari aktivitas pertanian dan limbah pemukiman yang terdapat di perairan Sungai Biyonga.
Tujuan penelitian ini untuk meningkatkan kemampuan menyimpulkan informasi berdasarkan teks hasil pengamatan melalui metode inkuiri pada siswa kelas SDN Banyudono Kaliori Rembang Tahun Pelajaran ...2020/2021.Penelitian ini merupakan penelitian tindakan kelas melalui dua siklus. Setiap siklus terdiri dari perencanaan, pelaksanaan, observasi, dan refleksi. Subjek penelitian ini pada siswa kelas VI SDN Banyudono Kaliori Rembang. Objek penelitian ini berupa proses pembelajaran menyimpulkan informasi berdasarkan teks hasil pengamatan. Teknik pengumpulan data menggunakan observasi, dokumentasi, dan tes. Hasil penelitian menunjukkan peningkatan dengan membandingkannya KKM nilai atau skor 80. Hal ini tercermin pada siklus I, bahwa nilai atau skor 80 atau lebih hanya 54,55 %, kegiatan kedua meningkat menjadi 54,55 %. Sedangkan rata-rata hasil belajar siswa dari kedua kegiatan di siklus I sebesar 54,55 %. Pada siklus II aktivitas pertama yang mencapai KKM adalah 72%, sedangkan aktivitas kedua yang mencapai KKM adalah 90%. Untuk keaktifan, siklus I pembelajaran pertama 57 %, pembelajaran kedua 84 %, siklus I pembelajaran II 90 %, dan keaktifan siswa II 100 %. Dengan kata lain hasil akhirnya, 90% dari 33 siswa dapat membuat kesimpulan dan 100% siswa aktif. Berdasarkan hasil penelitiian disimpulkan bahwa penerapan metode pembelajaran inkuiri meningkatkan kemampuan menyimpulkan informasi berdasarkan teks hasil pengamatan melalui metode inkuiri pada siswa kelas VI SDN Banyudono Kaliori Rembang Tahun Pelajaran 2020/2021.
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