Mathematical Approach: Integer Linear Programming using Branch and Bound Method for Optimizing Defense Facility Requirements in the New Soewondo Airbase

This journal explores the application of Integer Linear Programming (ILP) using the Branch and Bound approach to optimize the defense facility needs at Lanud Soewondo, Hamparan Perak, Deli Serdang. Lanud Soewondo, currently located in Medan, North Sumatra, plans to relocate to enhance flight security and support the defense of the western part of Indonesia. This study involves mathematical modeling with a focus on the number and types of squadrons and personnel requirements at the new Lanud Soewondo. Data from field studies and literature reviews are used to construct the ILP model, which includes combat squadrons, drone-based reconnaissance squadrons, and transport squadrons. The Branch and Bound method is employed to optimize these variables according to the available land area. The research results indicate that the optimal solution using ILP Branch and Bound is 1 combat squadron, 2 drone-based reconnaissance squadrons, and 1 transport squadron. The total land area required is 52 hectares out of the planned 600 hectares, with an optimal personnel requirement of 525 out of the total 577 DSP personnel. The remaining land area of 548 hectares can be allocated for additional facilities, while 52 personnel can be placed outside the squadrons. This study concludes that the ILP Branch and Bound method is effective in planning the optimization of defense facility needs at the new Lanud Soewondo, providing an efficient solution and supporting air defense in the Hamparan Perak region

KAJIAN PENGARUH WAKTU ELEKTROLISIS DAN ARUS LISTRIK TERHADAP PEMBENTUKAN ENDAPAN MASSA AG PADA KATODA PADA APLIKASI PELAPISAN LOGAM SENJATA

Elektrolisis merupakan proses pembentukan elektrolit berbasis ion perak, katoda berbentuk pelat logam senjata, dan anoda berbentuk batangan perak murni. Pada penelitian ini bertujuan untuk mengevaluasi pengaruh waktu elektrolisis dan arus listrik terhadap pembentukan endapan massa Ag pada katoda dalam aplikasi pelapisan logam senjata. Metode elektrolisis digunakan untuk menghasilkan endapan logam perak pada katoda, dan paramater waktu elektrolisis dan arus listrik diubah untuk mempelajari efeknya pada massa endapan perak dan sifat-sifatnya. Selama proses elektrolisis, waktu dan arus listrik divariasikan dalam rentang waktu 1 hingga 5 jam dan arus listrik 10 hingga 50 Ampere. Analisis dilakukan dengan mengukur massa endapan perak pada katoda, dan karakterisasi dilakukan menggunakan timbangan untuk mengetahui berat dari katoda yang terlapisi oleh perak. Hasil penelitian menunjukkan bahwa waktu elektrolisis dan arus listrik memiliki pengaruh signifikan pada pembentukan endapan massa Ag pada katoda. Sehingga pengaruh waktu elektrolisis dan arus listrik pada pembentukan endapan massa Ag pada katoda dalam aplikasi pelapisan logam senjata sangat signifikan. Penelitian ini dapat membantu pengembangan teknologi pelapisan logam yang lebih baik dan efektif untuk meningkatkan kualitas dan daya tahan senjata

ANALISIS KARAKTERISTIK MATERIAL PADAT (AMMONIUM PERCHLORATE) PROPELAN KOMPOSIT TERHADAP KINERJA PROPELAN LEMBAGA PENERBANGAN DAN ANTARIKSA NASIONAL (LAPAN) DALAM RANGKA PENGUASAAN TEKNOLOGI PROPELAN

Komposisi ammonium perchlorate dalam propelan komposit sekitar 75-85 %, dengan kandungan demikian ammonium perchlorate adalah material padat terpenting dalam propelan komposit. Propelan komposit merupakan bahan bakar pada roket dan rudal militer. Sebagai oksidator, ammonium perchlorate memiliki peran penting terhadap kinerja propelan LAPAN. Kinerja propelan LAPAN saat ini masih belum dapat mencapai standar, hal ini diprediksi oleh pengaruh dari karakteristik ammonium perchlorate dalam negeri yang mana masih rendah. Strategi dalam meningkatkan karakteristik ammonium perchlorate dalam negeri dan mengejar ketertinggalan dengan negeri-negara maju adalah dengan menganalisis bahan baku impor dari China dan Korea Selatan. Permasalahan yang akan diteliti adalah karakteristik ammonium perchlorate C200, H200 dan L200 yang digunakan seperti ukuran partikel, bentuk partikel, luas permukaan, dan luas permukaan partikel. Tujuan penelitian ini ialah melakukan analisis terhadap karakteristik ammonium perchlorate C200, H200 dan L200 sebagai penyusun propelan komposit, dan parameter yang paling berpengaruh terhadap rendahnya kinerja propelan. Penelitian ini menggunakan metode kuantitatif variabel terukur langsung dengan desain eksperimental di Laboratorium. Populasi pada penelitian ini adalah propelan komposit dengan sampel ammonium perchlorate dari China, Korea Selatan dan Indonesia (LAPAN). Instrument yang digunakan untuk memperoleh data adalah PSA (particle size analyzer), SEM, dan BET. Hasil dari penelitian ini diperoleh karakteristik material berupa ukuran partikel C200, H200 dan L200 adalah 265 µm, 236 µm, dan 242 µm. Diperoleh juga luas permukaan partikel sebagai berikut 1,104 m2/g, 5,561 m2/g, dan 2,972 m2/g. Bentuk partikel C200, H200 dan L200 ialah 0,68, 0,38 dan 0,33, dengan roundness 0,57, 0,79 dan 0,63.  Surface area merupakan parameter yang berpengaruh terhadap laju bakar yang mana juga memiliki pengaruh besar terhadap kinerja propelan. Hasil dari penenelitian ini penting untuk meningkatkan kinerja propelan LAPAN melalui peningkatan karakteristik ammonium perchlorate dalam negeri sehingga tercapai kemandirian bahan baku dan penguasaan teknologi propelan. Kata Kunci: Karakteristik Ammonium Perchlorate, Propelan Komposit, Kinerja Propelan, Pertahanan, LAPA

PENILAIAN PELAKSANAAN PROGRAM PENGEMBANGAN AGRIBISNIS PETERNAKAN SAPI POTONG DI KABUPATEN SEKADAU, KALIMANTAN BARAT

bjectives of this research were to analyze the characteristic of social demography of farmer’s participated in program and to carryout assessment. The implementation of agribusiness development program of beef cattle farmingin Sekadau Regency. This research was conducted from August until October 2009. One hundred and eight farmers participated in the program as respondents, selected by proportionate random sampling method, from five villages,locations of the program of livestock grant. Data of increasing population, number of investor, social demography characteristic of respondents and income contribution from beef cattle farming were analyzed by quantitative descriptive. Data of program implementation process, input and program implementation were analyzed by qualitative descriptive. Result showed that the beef cattle population increased about 152 heads and the investor increased about58 investors, respondent characteristics were age was 42.30±5.87 years old, majority of education level was on elementary school 43.52%, length of farming experience was 1.61±1,20 years, averages of cattle owning 1.88±1.05Livestock Unit (LU), the number of family support 3.36±1.15 head, and averages of time allocation of farming 0.078±0.082 HOK/LU/day, average income contribution from beef cattle farming was rangery from 8.21-24.09%.Program’s socialization in Sekadau Regency was not effective because many of the farmers had not fully understood about the objective and the implementation of the program, there was a distortion on the selection of farmers whoreceived livestock grant, farmer groups were not established based on the rule, were not involved members the arrangement of group business plan, breed determination and cattle specification, cattle’s specifications were not suitable with the condition. On the implementation step, there was a distortion of the fund, cattle specification and cost burden to the member, difference on mechanism of livestock grant revolving in each village. The increase of beefcattle population had not reached the determined target. It could be concluded that the implementation of agribusiness development program in Sekadau Regency has not been optimal.(Keywords: Social demography characteristic, Program implementation, Beef cattle

PENILAIAN PELAKSANAAN PROGRAM PENGEMBANGAN AGRIBISNIS PETERNAKAN SAPI POTONG DI KABUPATEN SEKADAU, KALIMANTAN BARAT

bjectives of this research were to analyze the characteristic of social demography of farmer’s participated in program and to carryout assessment. The implementation of agribusiness development program of beef cattle farming in Sekadau Regency. This research was conducted from August until October 2009. One hundred and eight farmers participated in the program as respondents, selected by proportionate random sampling method, from five villages, locations of the program of livestock grant. Data of increasing population, number of investor, social demography characteristic of respondents and income contribution from beef cattle farming were analyzed by quantitative descriptive. Data of program implementation process, input and program implementation were analyzed by qualitative descriptive. Result showed that the beef cattle population increased about 152 heads and the investor increased about 58 investors, respondent characteristics were age was 42.30±5.87 years old, majority of education level was on elementary school 43.52%, length of farming experience was 1.61±1,20 years, averages of cattle owning 1.88±1.05 Livestock Unit (LU), the number of family support 3.36±1.15 head, and averages of time allocation of farming 0.078±0.082 HOK/LU/day, average income contribution from beef cattle farming was rangery from 8.21-24.09%. Program’s socialization in Sekadau Regency was not effective because many of the farmers had not fully understood about the objective and the implementation of the program, there was a distortion on the selection of farmers who received livestock grant, farmer groups were not established based on the rule, were not involved members the arrangement of group business plan, breed determination and cattle specification, cattle’s specifications were not suitable with the condition. On the implementation step, there was a distortion of the fund, cattle specification and cost burden to the member, difference on mechanism of livestock grant revolving in each village. The increase of beef cattle population had not reached the determined target. It could be concluded that the implementation of agribusiness development program in Sekadau Regency has not been optimal. (Keywords: Social demography characteristic, Program implementation, Beef cattle

FAKTOR YANG MEMPENGARUHI KEMENANGAN INGGRIS DAN KEKALAHAN ARGENTINA PADA PERANG FALKLAND DALAM TINJAUAN PEMBERDAYAAN SUMBER DAYA PERSENJATAAN DAN ALUTSISTA

Kepulauan Falkland telah menjadi wilayah sengketa antara Inggris dan Argentina sejak abad ke-15. Perang Falklands terjadi di pulau-pulau ini. perjuangan berlangsung selama bertahun-tahun. Bahkan Argentina berhasil mengajukan klaim tentang pulau-pulau tersebut ke PBB. Pada tahun 1965, Perserikatan Bangsa-Bangsa menerbitkan Resolusi 2065, yang menyatakan bahwa masalah tersebut harus diselesaikan dengan mempertimbangkan kepentingan rakyat di kawasan tersebut. Argentina sendiri selalu menyatakan bahwa Falklands adalah bagian dari wilayahnya. Oleh karena itu, Argentina menginvasi pulau Malvinas pada tahun 1982. Inggris tidak setuju dengan tindakan Argentina tersebut. Pada metode penelitian yang digunakan dalam studi ini yakni penelitian tinjauan pustaka yang bertujuan untuk menyelidiki sejarah perang falklands dari kajian literatur dan studi pustaka. Adapun hasil dari kajian ini yakni Inggris mendapatkan kemenangan dari Argentina yang dimana dukungan internasional Britania Kuat, sementara Argentina menghadapi keterbatasan teknologi persenjataan, personel tentara perang kurang,  logistik juga sulit, dan strategi militer yang kurang efektif walaupun Argentina secara geografis sangat dekat jarak antara kepulauan falklands. Dibandingkan Inggris memiliki Keunggulan teknologi, dukungan internasional, dan kemampuan logistik menjadi faktor kemenangan Inggris, dan konflik ini berdampak pada hubungan politik antara kedua negara dan sengketa kedaulatan Kepulauan Falkland masih berlanjut

Investigation of thermomechanical analysis of carbon/epoxy composite for spacecraft structure material

When building spacecraft structures, it is crucial to use lightweight and high-strength composite materials with the necessary characteristics. Aerospace applications benefit significantly from the exceptional properties of carbon/ epoxy composite materials. As part of a study on composite materials, this work focuses on exploring the thermomechanical properties of carbon fiber. The matrix used in this research is LY-5052 epoxy, applied through a vacuum infusion technique. To achieve optimal composite properties, various tests are conducted to evaluate its thermomechanical behavior. These tests may include measuring Thermal Conductivity and performing thermogravimetric analysis (TGA). Most importantly, the composite is subjected to tensile testing at room temperature to 200 °C. This is done because most tensile tests on carbon/LY5052 composites are carried out at room temperature. The results obtained from the measurement of the thermal conductivity of the carbon/LY5052 composite were 0.419 W/mK; from the Thermogravimetric Analysis (TGA), the carbon/LY5052 composite began to decompose at a temperature of 365.63 °C and the tensile test was carried out simultaneously with variations in temperature from room temperature, 50 °C, 100 °C, 150 °C and 200 °C have tensile strengths of 553, 507, 340, 266, and 242 MPa, respectively. This trend confirms that strength decreases with higher temperature loads. Several image observations are also presented in this report to understand composite materials’ failure behavior at these various temperatures

Vitamin D supplementation alleviates insulin resistance in prediabetic rats by modifying IRS-1 and PPARγ/NF-κB expressions

BackgroundPrediabetes is a condition of intermediate hyperglycemia that may progress to type 2 diabetes. Vitamin D deficiency has been frequently linked to insulin resistance and diabetes. The study aimed to investigate the role of D supplementation and its possible mechanism of action on insulin resistance in prediabetic rats.MethodThe study was conducted on 24 male Wistar rats that were randomly divided into 6 rats as healthy controls and 18 prediabetic rats. Prediabetic rats were induced with a high-fat and high-glucose diet (HFD-G) combined with a low dose of streptozotocin. Rats with the prediabetic condition were then randomized into three groups of 12-week treatment: one group that received no treatment, one that received vitamin D3 at 100 IU/kg BW, and one group that received vitamin D3 at 1000 IU/kg BW. The high-fat and high-glucose diets were continuously given throughout the twelve weeks of treatment. At the end of the supplementation period, glucose control parameters, inflammatory markers, and the expressions of IRS1, PPARγ, NF-κB, and IRS1 were measured.ResultsVitamin D3 dose-dependently improves glucose control parameters, as shown by the reduction of fasting blood glucose (FBG), oral glucose tolerance test (OGTT), glycated albumin, insulin levels, and markers of insulin resistance (HOMA-IR). Upon histological analysis, vitamin D supplementation resulted in a reduction of the islet of Langerhans degeneration. Vitamin D also enhanced the ratio of IL-6/IL-10, reduced IRS1 phosphorylation at Ser307, increased expression of PPAR gamma, and reduced phosphorylation of NF-KB p65 at Ser536.ConclusionVitamin D supplementation reduces insulin resistance in prediabetic rats. The reduction might be due to the effects of vitamin D on IRS, PPARγ, and NF-κB expression

PENENTUAN KOMPOSISI BUTIRAN AP UNTUK MENDAPATKAN KOMPOSISI OPTIMUM PADA PROPELAN PADAT MENGGUNAKAN TEORI VOLUME KANTUNG (POCKET VOLUME THEORY)

Hlm.128-13