Judul: Penerapan Metode Heuristik Dalam Supply Chain Network Untuk Menentukan Jalur Distribusi Terpendek
Abstrak: Supply chain management is a process of manufacture and delivery of goods to consumers. One of the main factors of supply chain management is supply chain networks. Supply chain networks consist of two main parts, i.e. , the location of production and the distribution process. Both are related to the determination of optimum distribution channels or routes from producers to consumers which are related to time, distance, and vehicle capacity. This problem is called with the Vehicle Routing Problem with Time Windows (VRPTW). This research work was conducted in the supply chain division of KATRACO CV, a private company that engaged in the distribution of fuel oil to gas stations and several companies in Central Java and surrounding areas. This research aims to design a supply chain network for VRPTW case to minimize the total distance. In this work we used a heuristic method , i.e. , sweep heuristic, saving heuristic, and the nearest depot heuristic as constructing route. We also used 2-opt, relocate, and exchange methods as route improvement methods to determine a better routes. Furthermore, VRPTW problem is solved using ILOG Dispatcher program version 2.1 and ILOG Solver version 4.4, which is run in Microsoft Visual C + + version 6.0.
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Judul: The application of the heuristic method at the vehicle routing problem and its implementation at the PT Nippon Indosari Corpindo.
Abstrak: This paper is a case study in a division of PT Nippon Indosari Corpindo company. We used the vehicle routing problem with time windows (VRPTW) to formulate the distribution problem, which is a variation of the vehicle routing problem (VRP). In the VRP, all costumers have a time windows, so the service for the costumers must be completed in a specified time interval. The objective is to minimize the number of vehicles to serve all costumers in certain area and also to minimize the route length. As the VRPTW is a difficult problem in non polynomial hard problems, then we used the heuristic approach to solve the problem. In this paper, we used the nearest addition heuristic method to find the first solution. Next we used 2-Opt, Or-Opt, relocate, exchange, and cross methods to improve the first solution. In the last chapter of this paper, the results were compared to the current condition of the company. Key word: Vehicle routing problem, heuristic method, nearest addition heuristic method.
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Judul: Durability of Specific Immunoglobulin (Ig) Y Againts Influenza and Covid-19 in Sunscreen
Abstrak: The benefit of specific immunoglobulin Y (Ig Y) as an active ingredient in personal care products such as sunscreen has not been properly studied. Our study aims to evaluate the reliability of specific IgY against influenza and the COVID-19 virus in a sample sunscreen product. Specific IgY influenza and COVID-19 viruses were inserted in the sample sunscreen at two concentrations of 0.1% and 0.25%. Three treatments were observed: control (C) sunscreen without IgY, treatment 1 (T1) sunscreen with 0.1% IgY, and treatment 2 (T2) sunscreen with 0.25% IgY. Organoleptic observations were carried out to monitor changes in aroma, color, and texture, and sunscreen sampling was done every week for 6 weeks. The durability of IgY was evaluated using an enzyme-linked immunosorbent assay (ELISA) and a neutralization assay. Organoleptic observation from weeks 1 to 6 showed consistency in its aroma, color, and texture. Enzyme-linked immunosorbent assay and neutralization assay (NA) results of the T1 and T2 groups showed negative results except for sample T1 at week 5, which showed a positive result in the Influenza A ELISA. Based on the results, it seems that IgY concentrations of 0.1% or 0.25% were not optimal. However, this negative result might be due to low concentration of the IgY and the presence of beeswax, which inhibits IgY and causes it to dissolve in distilled water, thus preventing it from being detected in the assay.
Keyword: Immunoglobulin Y, Sunscreen, Influenza, COVID-19, Biological Activity