Beras merupakan bahan pokok pangan bagi masyarakat Indonesia dan hampir 90% masyarakat Indonesia mengonsumsi beras. Pada awal tahun 2018 harga beras mengalami peningkatan. Kenaikan harga beras ini jika terus dibiarkan akan menyebabkan terjadinya inflasi yang berdampak pada melambatnya pertumbuhan ekonomi nasional serta dampak negatif lainnya. Dalam rangka perumusan kebijakan pengendalian inflasi maka data dan informasi terkait proyeksi keadaan pasar sangat dibutuhkan. Oleh karena itu, pemodelan harga beras di Indonesia sangat perlu dilakukan. Sebagian besar sentra beras di Indonesia berasal dari provinsi di wilayah Indonesia bagian barat, sehingga pada penelitian ini dilakukan pengembangan model harga beras untuk wilayah Indonesia bagian barat dengan menggunakan pendekatan clustering time series. Pemodelan dilakukan dengan tahapan pengumpulan data, pemodelan ARIMA pada level provinsi, pemodelan ARIMA pada level klaster dan evaluasi keakuratan model dengan menggunakan MAPE. Hasil penelitian ini menunjukkan model ARIMA level klaster memiliki keakuratan yang lebih tinggi daripada level provinsi.

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In a decentralized supply chain condition, control of supply chain players towards third-party logistics service providers is limited, while the performance of logistics services affect product availability, quality, price and market. Outsourcing decisions on logistics activities are common practice and generally succeed in increasing the performance and efficiency of logistics costs for many companies. The kind of outsourcing could maintain their focus on the core business. On the other hand, these companies also need to keep minimizing distribution costs by managing relationships with third-party service providers to obtain the expected value of excellence in their operational performance. Therefore, in a decentralized supply chain, suitable supply contracts as the coordination mechanism among supply chain players are needed, moreover with the using of logistics outsourcing strategy. The supply contracts need to be designed so that all supply chain players could obtain the expected competitive advantage. In this research, there are revenue and inventory risk sharing contracts and quantity flexibility contracts developed to coordinate the supply chain consisting of manufacturers, retailers and third-party logistics service providers. An incentive and penalty scheme is applied based on the performance of the logistics service provider which affect the level of availability at the retailer, therefore the inventory risks could be allocated to all related players.

In this paper, a model for characterizing the dynamics of vector-borne diseases is put out, emphasizing Japanese encephalitis. The susceptible-infectious-recovered (SIR) model for the host population and the susceptible-infectious (SI) model for the vector and reservoir populations are used to examine the role of host-vector-reservoir dynamics and their interplay. The standard incidence rate represents the probability of an actual disease contact. The model has two equilibrium points: an endemic equilibrium point that only exists under specific circumstances and a disease-free equilibrium point that always exists. The stability analysis of the model’s equilibrium point has been established. The basic reproduction number is calculated using the next-generation matrix method. A sensitivity analysis on models supported by numerical simulations is provided to demonstrate the critical parameter that affects the spread of disease. Our findings indicate that vector-reservoir transmission is the primary cause of endemic. Controlling vector-reservoir transmission lowers the likelihood of human infection and creates disease-free settings.