Judul: Risk Analysis and Mitigation of Cheese Product Supply  chain at PT XYZ
Abstrak: Keju merupakan produk olahan susu yang memiliki berbagai manfaat, keju dapat dijadikan sebagai campuran makanan dan dapat dijadikan snack yang sehat. Keju memiliki karakteristik yang berbeda dari bahan makanan lainnya sehingga penting bagi perusahaan untuk memperhatikan risiko selama rantai pasok agar produk tetap dalam kondisi yang baik hingga konsumen akhir. Penelitian ini dilakukan untuk menganalisis kondisi situasional rantai pasok, mengidentifikasi kejadian risiko, agen risiko serta aksi mitigasi risiko. Analisis situasional menggunakan metode Food Supply chain Network (FSCN), yang dikembangkan oleh Van der Vorst. HOR (House of risk) digunakan untuk menganalisis risiko yang dilakukan pada dua titik yaitu distributor dan retailer. Pada titik distributor dan retail berturut-turut teridentifikasi kejadian risiko dan agen risiko sebanyak 15 ,11 kejadian risiko dan 23, 15 agen risiko. Terdapat empat prioritas tindakan mitigasi pada tingkat distributor dan enam aksi mitigasi risiko di tingkat retail. Menurut para pakar, tindakan yang sebaiknya dilakukan yakni mengadakan pelatihan internal secara rutin untuk meningkatkan kompetensi tenaga kerja dan melakukan evaluasi penerapan SOP., Cheese is a processed dairy product that has various benefits, cheese can be used as a food mixture and can be used as a healthy snack. Cheese has different characteristics from other food ingredients, so it is important for companies to pay attention to risks throughout the supply chain so that the product remains in good condition until the final consumer. This research was conducted to analyze supply chain situational conditions, identify risk events, risk agents and risk mitigation actions. Situational analysis uses the Food Supply chain Network (FSCN) method developed by Van der Vorst. HOR (House of risk) is used to analyze risks that are carried out at two points, namely distributors and retailers. At the distributor and retail points, 15,11 risk events and 23,15 risk agents were identified respectively. There are four priority mitigation actions at the distributor level and six risk mitigation actions at the retail level. According to experts, the best course of action is to conduct regular internal training to improve workforce competence and evaluate the implementation of SOPs.
Keyword: cheese, HOR, mitigation, risk, supply chain

Judul: Design of Measurement  Model and Improvement of Cheese Products Logistics Performance at PT XYZ
Abstrak: PT XYZ merupakan distributor untuk pengiriman barang dari luar maupun dalam negeri di Indonesia, salah satu produknya yaitu keju. Terjadinya lonjakan permintaan pasar menyebabkan PT XYZ perlu mengantisipasi layanan pengiriman yang dilakukan. Penelitian ini bertujuan untuk mengetahui mekanisme rantai pasok, menganalisis dan mengukur kinerja logistik, merumuskan strategi perbaikan, serta merancang model pengukuran. Pengukuran kinerja logistik pada retail PT PQR untuk bulan Desember 2022-Januari 2023 dengan model logistic scorecard dan metode analytical hierarchy process menghasilkan penurunan kinerja logistik sebesar 3,336% untuk grated parmesan (24x80) gr/ctn, sedangkan kenaikan sebesar 24,088% untuk block mozzarella (18x225) gr/ctn dan 2,186% untuk grated parmesan (16x200) gr/ctn. Berdasarkan analisis analytical network process, dihasilkan bobot tertinggi untuk strategi perbaikan sebesar 0,227 yaitu evaluasi kinerja logistik sesuai dengan key performance indicator sehingga dirancang model pengukuran berbasis Microsoft Excel. Hasil penelitian ini dapat digunakan sebagai acuan PT XYZ dalam upaya meningkatkan kinerja logistik., PT XYZ is a distributor for shipping goods from outside and within the country in Indonesia, one of its products is cheese. The surge in market demand caused PT XYZ to anticipate the shipping services that were carried out. This study aims to determine supply chain mechanisms, analyze and measure logistics performance, formulate improvement strategies, as well as design measurement model. Measuring logistics performance at PT PQR's retail for December 2022-January 2023 using the logistics scorecard model and the analytical hierarchy process method resulted in a decrease in logistics performance of 3.336% for grated parmesan (24x80) gr/ctn, whereas an increase of 24.088% for block mozzarella (18x225) gr/ctn and 2.186% for grated parmesan (16x200) gr/ctn. Based on the analysis of the analytical network process, the highest weight for the improvement strategy is 0.227, namely the evaluation of logistics performance according to the key performance indicators so that a measurement model based on Microsoft Excel is designed. The results of this study can be used as a reference for PT XYZ in an effort to improve logistics performance.
Keyword: cheese products, improvement strategy, logistics, model design, performance

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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