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"ABSTRAKTeknologi terus dikembangkan dalam dunia biomedis untuk menemukan cara pengobatan yang tepat dan murah. Sebuah metode untuk mengukur efekifitas anti mikroba adalah dengan metode uji silinder. saat ini, pengukuran zona inhibisi masih dilakukan dengan menggunakan caliper atau penggaris. Dalam penelitian ini, sistem instrumentasi untuk deteksi otomatis dan pengukuran zona inhibisi dikembangkan dengan menggunakan teknik pengolahan citra. Sampel zona inhibisi dalam cawan petri ditangkap menggunakan kamera dan diproses secara langsung di komputer.Pada penelitian ini perangkat lunak dibuat dengan memanfaatkan program Matlab berbasis Graphical User Interface GUI , Akhirnya, sistem pengukuran yang diusulkan sangat menjanjikan dan dapat digunakan sebagai alat untuk evaluasi efektivitas anti mikroba.

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ABSTRACTTechnology continues to be developed in the biomedical world to find the rightand inexpensive treatment. A method for measuring anti microbial effectiveness is by cup platemethod. Currently, inhibition zone measurements are still done manually using a caliper or ruler.In this study, the intrumentation sistem for automatic detection and zone measurement of inhibitionwas developed using image processing techniques. Samples of inhibition zones in petri dishes werecaptured using cameras and processed directly on the computer. In this research the software ismade by using Matlab program based on Graphical User Interface GUI . Finally, the proposedmeasurement sistem is very promising and can be used as a tool for evaluation of anti microbialeffectiveness. "

"Saat ini pengukuran diameter zona inhibisi anti-mikroba masih menggunakan alat ukur manual seperti penggaris atau jangka sorong. Teknologi saat ini memungkinkan untuk dilakukan pengukuran otomatis berbasis kamera digital non-metrik. Sebelum dapat digunakan, sistem ini memerlukan proses kalibrasi kamera dan kalibrasi spasial untuk melakukan transformasi nilai pixel ke nilai jarak. Pada penelitian ini diperkenalkan sistem kalibrasi kamera dan spasial secara otomatis. Sistem ini terdiri dari seperangkat instrumen pengukuran, kamera non-metrik dan teknik pengolahan citra. Teknik pengolahan citra diimplementasikan menggunakan pemrograman MATLAB. Pengujian dilakukan dengan menggunakan checkerboard standar pada berbagai variasi jarak, sudut orientasi dan kamera. Pengujian telah dilakukan menggunakan objek zona inhibisi anti-mikroba dan diperoleh hasil yang akurat. Rata-rata persentase kesalahan hasil pengukuran yang diperoleh dengan 2 cawan dan 5 zona sebesar 0,932 % (15 cm), 0,847 % (20 cm) dan 1,136 % (25 cm). Akhirnya, metode pengukuran ini dapat menawarkan pengukuran dengan hasil yang lebih baik dibandingkan dengan metode sebelumnya.

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Todays, the measurement of the diameter of the inhibition zones antimicrobial still using manual measuring tools such as rulers or calipers. The current technology allows for automatic measurement based non-metric digital camera. Before it can be used, this system requires a process of camera calibration and spatial calibration to transform pixel value to a distance value. In this study, introduced a system camera calibration and spatial automatically. The system consists of a set of measuring instruments, non-metric camera and image processing techniques. Image processing techniques are implemented using MATLAB programming. Tests carried out using standard checkerboard at various distances, angles and camera orientation. Tests have been carried out using the object anti-microbial inhibition zones and the results are accurate. The average percentage error of measurement results obtained with two bowls and five zones of 0.932% (15 cm), 0.847% (20 cm) and 1.136% (25 cm). Finally, this measurement method can offer measurements with better results than the previous method."

"Experiment on measurement of the magnetic susceptibility of ilmenite and its associate minerals was carried out. The sample used contained mostly of ilmenite and rutile. However, microparticle analysis helped to elucidate some associated minerals. It is found that each mineral has a unique value of magnetic susceptibility of ilmenite as an effort of improving of the separation. Nevertheless, excessive heating produces the reverse effect."

"The magnetic susceptibility and high magnetic ESR measurement of SrCu2(PO4)2 has been performed at temperaturesranging from 4.2 K to 300 K and 4.2 K to 77 K, respectively. The magnetic susceptibility shows a broad maximumaround T = 40 K. The magnetic susceptibility has been interpreted in terms of one-dimensional magnetic systems. Thetemperature dependence of the magnetic susceptibility indicated a good agreement with 4-spin alternating configurationmodel. In the ESR measurement, clear electron spin resonance (ESR) was observed. The integrated intensity for 120 and301 GHz has a broad maximum at around 40 K, which is consistent with the susceptibility result. A quantitativedescription gives resonance is the first and second triplet excited states of the excitation spectrum of 4-spin alternatingchain configuration. The g1, g2 and g3 values are approximately 2.21 at temperature above 40 K. The g2 dan g3 valueshave the dependence of temperature under 40 K."

"Tujuh Bukit merupakan wilayah yang memiliki deposit porphyry Cu-Au-Mo dengan kadar mineralisasi Cu dan Au tinggi yang terletak di Banyuwangi, Jawa Timur. Deposit porphyry memiliki beberapa tipe alterasi dan litologi yang memiliki konten magnetik tinggi dan berkorelasi dengan adanya mineralisasi Cu dan Au. Adanya hubungan antara konten magnetik dengan alterasi, litologi, dan mineralisasi pada deposit porphyry, menyebabkan pentingnya pengukuran geofisika yang mampu mengukur sifat fisis dari konten magnetik pada batuan deposit porphyry. Pada penelitian ini dilakukan pengukuran suseptibilitas magnetik batuan menggunakan instrumen magnetic susceptibility meter Terraplus KT-10. Hasil pengukuran suseptibilitas magnetik batuan selanjutnya dikorelasikan dengan data alterasi, litologi, dan mineralisasi. Korelasi dilakukan menggunakan strip log dan analisis statistika berupa box plot dan violin plot. Selanjutnya, dilakukan pemodelan tiga dimensi suseptibilitas magnetik dengan menggunakan metode interpolasi Radial Basis Function pada software Leapfrog Geo dan metode Kriging pada software Oasis Montaj untuk melihat persebaran suseptibilitas magnetik di sekitar titik penelitian. Hasil korelasi dan pemodelan tiga dimensi suseptibilitas magnetik menunjukan bahwa alterasi argillic, intermediate argillic, litologi old tonalite dan litologi precursor diorite memberikan respon nilai suseptibilitas magnetik yang tinggi dan berkorelasi dengan mineralisasi chalcopyrite, bornite, covellite, enargite, dan chalcocite.

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Tujuh Bukit is an area that has Cu-Au-Mo porphyry deposits with high levels of Cu and Au mineralization located in Banyuwangi, East Java. Porphyry deposits have several types of alteration and lithology that have high magnetic content and correlate with the presence of Cu and Au mineralization. The relationship between magnetic content with alteration, lithology, and mineralization in porphyry deposits, causes the importance of geophysical measurements that are able to measure the physical properties of magnetic content in porphyry deposit rocks. In this study, the magnetic susceptibility of rocks was measured using the Terraplus KT-10 magnetic susceptibility meter instrument. The results of rock magnetic susceptibility measurements were then correlated with alteration, lithology and mineralization data. The correlation was carried out using strip logs and statistical analysis in the form of box plots and violin plots. Furthermore, three-dimensional modeling of magnetic susceptibility was carried out using the Radial Basis Function interpolation method in Leapfrog Geo software and the Kriging method in Oasis Montaj software to see the distribution of magnetic susceptibility around the research point. The results of correlation and three dimensional modeling of magnetic susceptibility show that argillic alteration, intermediate argillic, old tonalite lithology and diorite precursor lithology give a high magnetic susceptibility value response and correlate with chalcopyrite, bornite, covellite, enargite, and chalcocite mineralization."

"Penelitian ini bertujuan untuk mengetahui daerah rawan tanah longsor di Kabupaten Dairi, Provinsi Sumatera Utara dengan menggunakan metode Spatial Multicriteria Evaluations (SMCE). Sebanyak 100 data inventaris kejadian bencana tanah longsor digunakan dalam penelitian yang berlangsung selama tahun 2018 – 2020. Data ini dibagi menjadi dua bagian yaitu 60 titik digunakan untuk pengolahan dalam menentukan peta rawan longsor dan 40 titik digunakan untuk validasi peta rawan longsor. Untuk menghasilkan peta rawan longsor, digunakan 12 parameter yang memiliki pengaruh terhadap terjadinya longsor yakni kemiringan lereng, arah hadap lereng (aspek), ketinggian (elevasi), bentuk lereng, formasi, jarak dari patahan, jarak dari sungai, topographic wetness index (TWI), stream power index (SPI), sediment transport index (STI), penggunaan lahan, dan jarak dari jalan. Selanjutnya masing-masing peta parameter dianalisis menggunakan metode SMCE melalui pendekatan analytical hierarchy process (AHP). Hasil pembuatan peta kerawanan longsor dibagi menjadi 5 kelas yang terdiri dari kelas sangat rendah, rendah, sedang, tinggi, dan sangat tinggi. Penentuan validasi peta kerawanan yang telah dibuat dilakukan dengan menggunakan metode kurva receiver operating characteristic (ROC). Nilai area under curve (AUC) pada kurva ROC hasil penelitian ini menunjukkan nilai akurasi  83,33 %. Berdasarkan nilai tersebut, maka model peta yang dihasilkan dapat digolongkan memiliki akurasi yang tinggi. Peta daerah rawan longsor yang dibuat dapat berguna sebagai upaya mitigasi bencana di Kabupaten Dairi, Provinsi Sumatera Utara.

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This study aims to determine landslide susceptibility areas in Dairi Regency, North Sumatra Province using the Spatial Multicriteria Evaluations (SMCE) method. A total of 100 pieces of inventory data for landslide events were used in the research that took place during 2018 – 2020. This data was divided into two parts, 60 points were used for processing in determining landslide susceptibility map and 40 points were used for validation of landslide susceptibility map. To produce a landslide susceptibility map, 12 parameters are used that influence the occurrence of landslides, including  slope gradient, slope aspect, elevation, curvature, lithology, distance from faults, distance from rivers, topographic wetness index (TWI), stream power index (SPI), sediment transport index (STI), land use, and distance from roads. Furthermore, each parameter map was analyzed using the SMCE method through the analytical hierarchy process (AHP) approach. The result of making landslide susceptibility map is divided into 5 classes consisting of very low, low, medium, high, and very high classes. Determination of the validation of the susceptibility map that has been made is done using the receiver operating characteristic (ROC) curve method. The area under curve (AUC) value on the ROC curve shows an accuracy value of 83.33%. Based on these values, the resulting map model can be classified as having high accuracy. The map of landslide susceptibility areas that is made is expected to be useful as a disaster mitigation effort in Dairi Regency, North Sumatra Province."

"Fenomena transfer spin pada sistem lapisan magnetik dapat dipahami sebagai interaksi antara normal metal dengan lapisan feromagnetik terdekatnya yang dipengaruhi oleh suseptibilitas magnetik normal metal. Sebagian besar kajian eksperimen terhadap fenomena transfer spin menggunakan logam berat seperti Paladium dan Platina yang memiliki interaksi Coulomb yang cukup besar, sementara itu teori yang ada saat ini mengasumsikan memakai logam ringan, yang mengabaikan interaksi Coulomb tersebut. Pada penelitian ini, kami bertujuan untuk mempelajari secara teoretis pengaruh dari interaksi Coulomb terhadap suseptibilitas magnetik kompleks. Kami memakai model satu pita energi dengan menggunakan perhitungan Density Functional Theory (DFT), model Hubbard dan model Tight-binding. Hasil perhitungan menunjukkan bahwa untuk logam berat, sifat material didominasi oleh orbital-d, dan suseptibilitas magnetik kompleks mengalami penguatan akibat adanya interaksi Coulomb. Pada logam transisi seperti Pd dan Pt, kulit terluar memiliki orbital-orbital d dan orbital s yang dapat berinteraksi. Kami melakukan kalkulasi pendekatan dua pita energi dengan menggunakan model Anderson, Density Functional Theory, interpolasi Wannier, dan intepolasi pita energi. Dari hasil DFT kami mengamati adanya hibridisasi orbital-s dengan orbital-d. Hasil perhitungan teoretis menujukkan bahwa untuk elektron pita konduksi dari orbital-s, besaran Stoner proporsional terhadap kuadrat dari parameter hibridisasi serta berkebalikan dengan kuadrat dari selisih energi elektron orbital-s terhadap energi dari elektron orbital-d. Hasil perhitungan juga menujukkan bahwa untuk sistem fermion berat, nilai suseptibilitas magnetik ditentukan oleh nilai massa efektif elektron. Hasil perhitungan kami menunjukkan bahwa model dua pita energi mampu memodelkan suseptibilitas magnetik dengan akurat.

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Spin transfer torque in a magnetic multilayer system can be viewed as interaction between a normal metal and adjacent ferromagnetic layer. The magnetic susceptibility of normal metal plays essential role in characterizes the interaction. Most experimental studies on this subject utilize heavy metals, such as Palladium (Pd) and Platinum (Pt), that possess large Coulomb interaction, while a recent theory assume a light metal as normal metal, which neglect the Coulomb interaction. In this research, we aim to theoretically investigate the effect of Coulomb interaction to the complex magnetic susceptibility of Pd and Pt. We calculate a single-band susceptibility for Pd and Pt by applying Density Functional Theory (DFT), tight-binding model, and Hubbard model. For single-band susceptibility,  our final results show that the d-orbitals dominate the band structure with large repulsive interaction that enhances the magnetic susceptibility. To extend our study, we calculate the more complex approaches. Transition metals Pd and Pt outer shell d-orbitals and s-orbital can interact. We calculate the double-band model using the Aderson model, Density Functional Theory, Wannier interpolation, and band fitting. From the DFT calculation, we observe s-d hybridization for Pd and Pt. Our theoretical results show that for conduction electron, the Stoner term is proportional to the square of the hybridization parameter and the inverse of the square of the energy difference between the s and d-electron. We also obtain that for the heavy fermionic system, the magnetic susceptibility value strongly determined by the effective mass of the electron. Our results show that dual-band model is sufficient to model the magnetic susceptibility accurately. "