• 한국통신학회논문지
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• 제22권12호
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• pp.2626-2634
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• 1997

The purpose of multicasting is to reduce the network costs for transmitting the same traffic to multiple destinations. In this paper, an efficient delay-bounded multicasting routing algorithm is proposed, which satistifies the network conditions of cost minimization and can adjust the dynamic events, such as 'leave and/or join ones' from the multicast group. Also, our algorithm is designed for various network requirements such as the efficiet dynamic group support, high-quality data distribution, and adaptability to variable situation. After the delay tolerance and the maximum group size are determined according to network state and requirements for delay and cost, the dynamic delay-bounded multicast tree is constructed using partial multicast routing. We evaluate the performance of the proposed algorithm by running simulations on randomly generated test networks using a Sun Sparc 20 workstation. We were able to obtain good simulation resutls, which means solutions that lies between the minimum cost solution and the minimum delay one.

• 전기학회논문지
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• 제64권5호
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• pp.661-666
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• 2015

This paper proposes a method for solving running cost problem by minimizing switching reactive power compensation devices. An objective function was modeled by calculating the weighting value of cost, and a solution was derived using ILP. This paper suggests optimal coordinative control method between FACTS, Shunt Reactors, Capacitors and OLTC. Therefore, it is valuable for decision maker in determining order and capacity of devices which gaining a voltage stabilization. As a result, the objectives of voltage stabilization and cost minimization were achieved simultaneously. This realizes the economic efficiency of the system. We start by showing how to solve systems of linear equations using the language of pivots and tableaus. The effectiveness of this technique is demonstrated in modified PSS/E MIGUM 45 bus system. The simulation results show the effectiveness of this algorithm by comparing the outcome withseveral established methods.

• 한국지열·수열에너지학회논문집
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• 제15권1호
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• pp.9-17
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• 2019

Reducing global warming potential has become important, and as one of those methods for reducing it, economic evaluation by applying ice thermal storage air conditioning system was performed. The floor area and height of the subject building was assumed $5,000m^2$ and 20 m. Absorption chillerheater system and air source heat pump system was used for comparing to the subject system, and payback period method was used to perform economic evaluation. Although the running cost of ice thermal storage system is reduced compared to two systems, the ratio is not significant compared to the increase of initial construction expenses, and payback period was calculated to be about 7.7 and 79.3 years. However, the heat storage system should be approached from the viewpoint of long term rather than the economic standard in the present standard.

• Journal of applied mathematics & informatics
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• 제41권1호
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• pp.215-228
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• 2023

The ready-made garments (RMG) have been making a crucial contribution about of 81% of total export and 12.36 % of total GDP of the country which is now the single biggest export earner for Bangladesh. The cheap production cost is the key important factor to explore this RMG sector. But these RMG sector is running on the basis of intuition based decisions. Though they are making profit it is not optimal. In this study, a deterministic model is developed to help the RMG to minimize the production cost and to maximize their profit along with optimal utilization of available resources. 10 different types of products are taken from one of the garments factories of Gazipur, Dhaka to prepare this research work. This model suggests the manufacturer on which products along with how much should be produced to meet the future demand by maintaining the lowest production cost that ultimately maximize the profit of the organization, and also helps Bangladesh to compete in the international market with 'Made in Bangladesh'. LINDO programming is used here to solve this LP model.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2007년도 제32회 펄프종이기술 국제세미나
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• pp.83-125
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• 2007

Increasing energy costs have caused profitability problems for paper suppliers. Therefore unprofitable lines are being closed down. The actions aiming for improved profits are focused either on cost savings or on increasing the capacity of the remaining machines. The runnability of a paper machine and its total efficiency have a significant effect on energy consumption. Producing one ton of waste paper consumes at least as much energy as producing the same amount of sellable end product. New automation solutions enable significant cost-effective improvements to the total efficiency of a line without large investment projects. The measures focus on minimizing changes, interruptions, interruption recovery times and grade change times. Newest actuators, online quality measurements and wet end analysators create an improvement potential, which can be optimally implemented with the latest machine direction control solutions, based on model predictive control concepts. Equally, drying management is significant to the energy consumption. The newest control strategies optimize the use of various drying actuators for different situations; either by responding to changes as efficiently as possible or by using only the cheapest energy sources in stable situations. An even steam supply, which is vital for paper machines, is achieved with control for the power plant steam network. This makes possible to avoid the delays upon starting the paper machine and assure an even steam supply for the drying section and the actuators. This document describes means which have brought significant energy and raw material savings for paper machines. Metso Automation has provided efficiency improvement packages, which are usually based on optimized control of dry weight and drying in all running conditions. The solutions are based on performance analysis, on which the estimations for improvement potential and the necessary actions are based on. Typically benefits on an annual level have been from hundreds of thousands of euros to over one million euro. For example, variations in dry weight have been decreased more than 50%. The results are presented with a few examples. Additionally, the analysis models, adjustment solutions and the changes in running methods with which the results were achieved, are presented.

• 한국콘텐츠학회논문지
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• 제14권11호
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• pp.102-110
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• 2014

본 연구는 공연여건의 성장에 걸 맞는 투자시스템으로의 변화를 모색하는 데 있다. 특히, 제작사들이 원하는 장기공연이나 오픈런 방식으로 공연여건이 조성되고 있는 상황에서 연장공연 여부를 신속히 판단할 수 있고, 제작자와 투자자 양자가 만족할 수 있는 미국식 예산수립 방식으로의 변화모색이 필요한 시점이다. 이에 구체적으로 3가지 방안을 제시하였다. 첫째, 연장공연이나 재공연 여부를 보다 정확히 판단하기 위해서는 현재와 같이 평균비용(Average Cost)을 산출하여 평균수입과 비교하기보다는 미국과 같이 한계비용(Marginal Cost)을 산출해서 비교해야 할 것이다. 둘째, 수익배분에 대한 불합리성을 극복하기 위해서는 현재와 같이 총제작비를 투자모수로 삼기보다는 미국과 같이 총제작비에서 운영비용(Operating Cost)을 제외한 프로덕션비용(Production Cost)만을 투자모수로 삼아야한다. 셋째, 앞서 언급한 한계비용의 산출과 프로덕션비용의 산출을 위해서는 미국 지출예산(Expense Budget)의 이원화 작성법의 국내 적용이 필요하겠다.

• 한국산학기술학회논문지
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• 제14권2호
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• pp.696-706
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• 2013

본 연구는 DEA모형에 바탕을 둔 표준원가에 기초한 원가차이 분석의 개념을 구현할 수 있는 모형을 설계하고 69개 종합병원의 투입 산출물을 이용해 효율성 분석과 원가관리 방안을 살펴보았다. 이를 위해 DEA모형을 통해 달성가능한 목표원가를 구하고 이를 실제원가와 비교하여 차이분석모형의 틀을 구축하였다. 또한 이 모형을 바탕으로 의사 간호사 인건비 정보를 구해 2008년도 결산기준 69개 종합병원의 표준원가차이를 구하고 이를 기술적 비효율성으로 인한 원가차이, 가격 비효율성에 기인한 원가차이, 표준예산원가 원가차이로 분리하여 원가관리의 새로운 방식을 제시할 수 있었다. 또한 실증분석을 통해 69개 종합병원은 병상수와 같은 규모를 늘리는 것이 효율성 개선에 기여하지 않으며 오히려 예산목표원가 관리 측면에서는 비효율적인 것으로 나타나 규모 확장 일변도의 전략을 수정할 필요가 있는 것으로 나타났다.

• 한국건축시공학회지
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• 제1권2호
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• pp.154-164
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• 2001

This research is aiming to specify the requirement of the investment such as intial cost, running cost earning rate to make effective investment considering the purpose of remodeling and economical value of store building enough to meet the initial purpose of remodeling. The review of earning for economical evaluation was performed by the on-site auditing on the structure and function of the building and applying the assessment simulation program, which is to find the possible business model to identify the requirement of building owner through case study. After the research, the following results are obtained. First, it is important that many aspects should be carefully analysis and the best method should be selected as characteristics of remodeling can be defer each other in their implementations. Second, though the remodeling of exist building to promote the functions has been applied, no suitable assessment tool has bee developed for deciding the level of remodeling in the view of economical efficiency so far. Third, the economical benefit was evaluated by analysing annual earning rate which is applied by investment items and recovery period for the investment. More specific date base should be established to apply the suggested economic acessments in business enough ti forecast the future circumstances. More researches should be promoted on the area continuously as well as the integrated economic evaluation of remodeling on existing building.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.437-446
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• 2005

Recently as people's values are changing from development phase into running stage after quality of life, so that the needs of environmentally friendly construction are gradually increasing. Also populace discontent about the pollution during construction process such as the noise and vibration caused by construction machinery is increasing. Even though it is impossible to eliminate the construction pollution fully, it is necessary to make efforts to reduce construction pollution to a minimum. In terms of construction site operating, the first possible step for solving these matters directly is that the necessary sum of expenses must be secured as the environmental management costs in the conceptual phase. However, in fact, the environmental management costs have not been secured in the budget. Generally it is the major reason not arising proper activities to prevent the pollution in the construction site. The purpose of this research is to suggest the efficient budgeting method regarding Environmental management costs to ensure the necessary sum of environmental management expenses. To provide an efficient budgeting method, interviews with the person in charge of environment management was conducted. 78 construction sites was surveyed and environmental management costs were analyzed through their historical data from the survey. According to the results of analysis, the ratio of environmental management costs is revealed 0.45% of construction cost as average comparing 0.2% of legal limit. And usually the environmental management cost was appropriated into the safety management budget. So it is needed to isolate environmental management budget securely and modify the ratio of Environmental conservation Costs in Construction Technology Management Act.

• 로봇학회논문지
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• 제7권2호
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• pp.76-82
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• 2012

In this study, we aim to develop energy efficient walking and running robot with compliant leg. So, we propose the energy efficient locomotion control method. And, we experiment the proposed control method applying to the experimental robot with compliant leg. From the experiment, we look at whether the proposed control method can the robot walk and run energy efficiently.