Judul: Masalah Penjadwalan Kereta Secara Periodik dengan Biaya Minimum pada Jalur Ganda
Abstrak: Train scheduling problem is an interesting topic to be discussed, since train has become such an important mass transportation in Indonesia. For that reason, this paper discusses how to solve a minimum cost scheduling problem (MCSP). The train scheduling problem that minimizes operation cost is formulated by MCSP in the form of integer programming. MCSP can be divided into two sections, i.e. minimum cost train problem (MCTP) and scheduling problem. In the first step, the right train is chosen with MCTP for a route, which satisfies a minimum cost. Furthermore, the next step solves the scheduling problem for the chosen train. The schedule is formulated only for one time period, which is assumed periodic. This solution is carried out by LINGO 11.0. The result gives the train scheduling for the specific route, which has minimum operation cost.
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Judul: Optimasi Biaya Operasional Kereta Api dalam Sistem Loop Line Menggunakan Pemrograman Integer Taklinear
Abstrak: High demand for transportation that causes passenger’s congestion in some stations is one of the main problems faced by PT KAI commuter Jabodetabek (KCJ). This problem can be solved by determining optimal routes and frequencies of the trains. This paper presents a model to determine routes and travelling frequency for each route in order to minimize the total cost. The problem is modelled as a nonlinear integer programming. This model is implemented in Jabodetabek railway network that have been simplified. The parameters of the model include the demand of passengers, the capacity of trains, maximum travelling of train for each route, and operational costs. Developing model is started with identification of all the requirements of the system. All of the requirements then are formulated as linear equalities or inequalities. Ensuring the validity of model is done via solving several scenarios using the model. The solution of the model is obtained using LINGO 11.
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Judul: Pemanfaatan Ekstrak Bunga Rosela (Hibiscus sabdariffa L) Kaya Antioksidan Dalam Pembuatan Mayonnaise Berbahan Dasar Minyak Kelapa, Minyak Sawit, dan Minyak Kedelai
Abstrak: The addition of Rosella flower extract and utilization various oli such as coconut, palm and soy were being involved in production of mayonnaise. Mayonnaise is a kind of ketchup which use canola or olive oil, egg, salt, and pepper and had been developed in France. The addition of Rosella extract (5%, 10% and 15%) base on amount of oil that used in production. Mayonnaise formulation are 75-78% oil, 6-9% egg yolk and flavors. Hedonic and hedonic quality sensory evaluations tested base on kind of oil. Base on evaluation the addition of Rosella extract statistically influenced color and thickness of coconut oil mayonnaise, color of palm oil mayonnaise, color and taste of soy oil. Fat analyze showed that there were statistically no difference between selected mayonnaise as well as protein and carbohydrate. Antioxidant activity and anthocyanine analyze showed that there were statistically difference between mayonnaise. Highest antioxidant activity and anthocyannin reached by palm oil mayonnaise with 15% Rosella extract.
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