• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.5
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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.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.15 no.1
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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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• v.41 no.1
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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.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2007.05a
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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.

• The Journal of the Korea Contents Association
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• v.14 no.11
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• pp.102-110
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• 2014

It is a time to change the investment system for performances of co-producing according to development of the environment of performing arts in Korea. If we keep producing performances through the conventional method of the investment, we soon fall behind because production costs will increase by extension of the performance period. Investment companies generally require to the production company the investment principal guarantee as a condition for a investment. Producing companies have been producing performance with only ticket revenue and money of investment companies without their own money. Those two unreasonable things have raised a risk. So first of all, it is necessary to account marginal cost instead of average cost to decide more exactly open-running of performance. Second, it is necessary to change total cost as an investment parameter to production cost to avoid the unreasonable demands, such as a principal guarantee to production company. Therefore, we have to accept the budget planning of the United States to account the marginal cost and the production cost.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.696-706
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• 2013

This study aims to develop DEA model which can look into budget cost variance analysis tool based on standard cost using 68 hospital's input and output data. For accomplishing this purpose, by introducing new DEA model which can get an attainable target cost, we can decompose an actual cost difference into several meaningful sub variances. Also based on the 2008 general hospital data, this model can make variance analysis between actual cost and target cost. Total variance can be divided into technical inefficiency variance, price inefficiency variance, allocation inefficiency variance. This study introduces that by using target budget cost concept, traditional actual cost variance can be divided into a technical variance, price variance, budget variance. Finally, we can get result which confirms there does not exist favorable size effects on efficiency and cost management in running a general hospital.

• Journal of the Korea Institute of Building Construction
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• v.1 no.2
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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.

• International conference on construction engineering and project management
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• 2005.10a
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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.

• The Journal of Korea Robotics Society
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• v.7 no.2
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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.

• Journal of Applied Reliability
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• v.11 no.1
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• pp.83-95
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• 2011

Boiler efficiency has a direct impact on energy consumptions, which results in lower cost of operations and services. Usually high efficiency boilers are regarded as boilers with an efficiency of greater than 90%. However, it is likely that normal boilers are running at significantly lower efficiencies than this. This paper presents a process of developing a highly efficient energy consumption boiler. We adopt direct heat method while normal boilers are designed as indirect heat method. The submerged combustion method is considered to design for very high efficient boiler.