• Management Science and Financial Engineering
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• 제16권3호
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• pp.21-47
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• 2010

Quantity discounts provide a practical foundation for supply chain inventory policies, improving the supplier's profit and reducing the buyer's inventory cost simultaneously. Traditional quantity-discount research, which deals with inventory coordination between a buyer and a supplier, is extended to a stationary stochastic environment. This research shows that the magnitude of the optimal discounts scheduled by the deterministic quantity discount models may not be large enough to cover the buyer's additional inventory stocking risks under uncertain conditions. As a result, the buyer's total inventory cost may often increase rather than decrease. In contrast, the proposed model allows the supplier to identify the discount level, which shares the buyer's amplified risk associated with temporary overstocking and ensures that both buyer and supplier benefit economically. The performance of the proposed model was tested in the continuous review environments via numerical experiments. The experimental results support the proposed method as a feasible alternative in coordinating inventory decisions under stochastic demand.

• 수산해양기술연구
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• 제45권4호
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• pp.276-286
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• 2009

The main purpose of this research is to analyze economic feasibility of biodegradable sonw crab gill net model project. The results of benefit/cost analysis show that use of the biodegradable gear is economically feasible. Assuming that the rate of gill net lost is 5 percent, net present value was estimated 311,898,282-590,533,375won, benefit-cost ratio 1.816-1.923 and internal rate of return 7.96-10.59%. The development and diffusion of biodegradable fishing gear appear to make a significant contribution to fisheries resource conservation and marine ecosystem protection. In addition, biodegradable gear production firms may have a good opportunity of exporting it to other coastal states, depending on the progress of WTO subsidy negotiation.

• 한국안전학회지
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• 제25권3호
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• pp.28-33
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• 2010

Ni alloy steel is able to use during long time because of good acid and corrosion resistance. So, it's research has focused on developing the alternative alloy which is economically feasible. Recently, consumption of Kovar steel is gradually increased in field of the jet engine and the gas turbine because of its low thermal expansive characteristics. The specimens of Kovar steel(29%Ni-17%Co) contain 0.00%C, 0.03%C, 0.06%C, 0.10%C and 0.20%C, respectively. Ingots are manufactured by VIM(vacuum induction melting furnace) and then specimens are made by automatic hot rolling after heat treatment. Strength of Kovar steel according to carbon contents is estimated by hardness, tensile and impact test. Hardness of the 0.20%C specimen is more improved approximately 14.4% than one of base metal. Its strength increases 32.4% of a base metal, and its impact energy is also enhance 11.5%.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2008년도 한국컴퓨터종합학술대회논문집 Vol.35 No.1 (A)
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• pp.261-262
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• 2008

Due to technological advances, the manufacturing of small and low cost of sensors becomes technically and economically feasible. In recent years, an increasing interest in using Wireless Sensor Network (WSN) in various applications, including large scale environment monitoring, battle field surveillance, security management and location tracking. In these applications, hundreds of sensor nodes are left to be unattended to report monitored data to users. Since sensor nodes are placed randomly and sometimes are deployed in underwater. It is impossible to replace batteries often when batteries run out. Therefore, reducing energy consumption is the most important design consideration for sensor networks.

• Asian-Australasian Journal of Animal Sciences
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• 제12권3호
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• pp.449-459
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• 1999

Non-conventional roughage (NCR) is shrub and tree fodders, crop residues and agroindustrial oy-products which is not commonly used as livestock feed traditionally and commercially. Eventhough many sources of NCR is available, the farmers perceptions on NCR not only vary from country to country in tropical and sub-tropical Asian-Australasian countries, but also vary from region to region within the country. Chemical composition and nutritive value of NCR are not only vary from species to species but also vary between species within the genera, between provenances/cultivars within the species and such variations are affected by season, climatic zone, topography and land utilization. The nutritive value of NCR can be improved by physical, chemical and biological treatments and conservation. Feeding NCR to ruminant and non-ruminant is not only improve performance of the livestock but also economically feasible. Future direction of NCR is inventarization, exchange information through NCR information centre, integration with either agrisilvicultural, agrisilvipastoral or silvipastoral system, and use of genetic engineering to produce high quality NCR that ultimately become conventional roughage for agroindustry and agribissiness.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(II)
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• pp.14-19
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• 2003

This paper is aiming to analyse the prefeasibility study of introduction of high speed rail freight system to transport some parcels for train operation efficiencies. As it does, this system can be meant a kind of multimodal system considering the passenger and freight in the same trainset, simultaneously. First, we implemented the parcel service market survey for customers preference, predicted demand forecast for high speed rail freight, and analysed B/C, NPV, etc.. As the result, this new system is feasible of applying the passenger-freight operation system economically, find the needs such as some revision of motor car for parcel freight transportation at the initial stage.

• 소성∙가공
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• 제24권5호
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• pp.332-339
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• 2015

In the current paper, a cold forging sequence was developed to manufacture a precisely cold forged H/Lower, which is used as the air back unit in commercial automobiles. The preform shape of the H/Lower influences the dimensional accuracy and stiffness of the final product. The shape factor (SF) ratio and shape of the tools are considered as the design parameters to achieve adequate backward extrusion height and maintain appropriate thickness variations. The optimal conditions of the design parameters were determined by using an artificial neural network (ANN). To experimentally verify the optimal preform and tool shapes, the experiments of the backward extrusion of the H/Lower were executed. The process design methodology proposed in the current paper, can provide a more systematic and economically feasible means for designing the preform and tool shapes for cold forging.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.48-49
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• 2014

Green Frame is a column-beam system that uses composite precast concrete members. Previous studies have proven this system to be not only structurally safe, constructible, and economically feasible, but also environmentally-friendly. If the computerized program is used to estimate the quantity, the result of it shall be calculated much easily, quickly and exactly than manual estimation, because precast concrete members of Green Frame has standard size and connection method between it. Therefore, this study suggest quantity survey concept for column-beam structure comprised of composite precast concrete members. Hereafter, the quantity survey of Green Frame shall be much quickly and accurate, if the system would be made based on the result of this study.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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• pp.313-316
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• 2006

As Decentralized Generation(DG) becomes more reliable and economically feasible, it is expected that a higher application of DG units would be interconnected to the existing grids. This new market penetration of DG technologies is linked to a large number of factors like technologies costs and performances, interconnection issues, safety, market regulations, environmental issues or grid connection constrains. Korea Electric Power Corporation (KEPCO) has researched performance characteristics of the 60k W class 1) basic start-up & shutdown operation analysis 2) interconnection test 3) MGT -absorption chiller-heater system in the local condition. Variations of heat recovery from exhaust gas has measured according to micro gas turbine output of 15, 30, 45, 60kW. From those results, the performance of the MGT-absorption chiller/heater system has been evaluated. The suggested strategy and experience for the evaluation of the distributed generation will be used for the introduction of other distributed generation technologies into the grid in the future.

• 한국해양바이오학회지
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• 제4권1호
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• pp.11-14
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• 2010

The genus Porphyra, consisting of 133 species includes several economically valuable species (i.e. P. yezoensis, P. tenera, P. pseudolinearis etc.). They are predominantly consumed and cultivated in East Asian countries such as Japan, Korea and China, and they are regarded as a big commercial market today. In addition to the industrial importance, P. yezoensis is currently regarded as a feasible candidate for a model plant in marine biotechnology, therefore there are a wide range of studies being undertaken: strain-preservation, development of mutant strains and genetic analysis and exhaustive molecular analysis including EST and macro/micro array. Focusing on the activities of our research group, current situation and future perspectives in marine biotechnological studies using P. yezoensis will be discussed in this mini review.