• International Journal of Air-Conditioning and Refrigeration
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• 제13권1호
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• pp.31-43
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• 2005

The new HVAC system is developed to lower the conveyance energy and building height using IAV(Increasing Air Volume) technique. IAV units which are equipped in each zone carry out air-conditioning and supply fresh air by induction of outdoor air in main duct. The design program which decides size of OAHU and IAV unit according to air conditioning load and fresh air demand of each zone is presented. The control system is developed to operate efficiently HVAC system and IAV unit, so that individual zone operation and well-deal with partial load and IAQ problem are possible. The new system is investigated in model building and makes more profit in conveyance energy. size of air conditioning facilities room and building height than VAV system. But in construction cost it is worse by about 15 percentage.

• Journal of Industrial Technology
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• 제27권A호
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• pp.185-193
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• 2007

The object of this study is the development of a Method which is enable to review the preliminary feasibility for co-generation system in new apartment buildings. In Korea co-generation systems have been installed in most of large industrial plants and commercial buildings which consume a large quantity of electric and heat energy, for energy saving and cutting products cost, under positive governmental supports. However for apartment buildings which consume quite a large electric and heat energy, are still remained in conventional energy supply system, and are not popular to utilize useful co-generation system. One of the major reason for these is the lack of clear and easy justification tool. In this circumstance, this study can provide a tool to verify the feasibility of co-generation in apartment buildings with this handy tools for planners and designers beforehand.

• Journal of Ocean Engineering and Technology
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• 제14권4호
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• pp.62-97
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• 2000

Recently the research for utilization of waste heat produced from electric power plants, casting factories, heat treating factories or commercial are being afforded by the need for energy saving. The objective of this study is to develop a thermoelectric generation system which unused energy from close-at-hand sources such as garbage incineration heat and industrial exhaust etc. into electricity. This paper a thermoelectric technology on a optimum system design method and efficiency and cost effective thermoelectric element on order to extract the maximum power output from energy conversion of waste energy. It is shown that the longitudinal stresses of module contacted with two point constrained Al tubes could be released more than those with a one-point constrained.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1326-1329
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• 2009

In large-area LCD displays, we have developed two new control technologies for high-power LED backlight. The Novel control technology called scanning control and local gray control. In addition, a conceptual display system power management was developed. We have implemented high power-LED module driving system which can achieve power saving and cost down. Finally, we designed LED light-bar module of the side type as a backlight source. It not only achieved light & thin but also reduced the quantity of LEDs.

• Industrial Engineering and Management Systems
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• 제12권2호
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• pp.161-170
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• 2013

Deployment of green transportation in reverse logistics is a key issue for low carbon technologies. To cope with such logistic innovation, this paper proposes a hybrid approach to solve practical vehicle routing problem (VRP) of pickup type that is common when considering the reverse logistics. Noticing that transportation cost depends not only on distance traveled but also on weight loaded, we propose a hierarchical procedure that can design an economically efficient reverse logistics network even when the scale of the problem becomes very large. Since environmental concerns are of growing importance in the reverse logistics field, we need to reveal some prospects that can reduce $CO_2$ emissions from the economically optimized VRP in the same framework. In order to cope with manifold circumstances, the above idea has been deployed by extending the Weber model to the generalized Weber model and to the case with an intermediate destination. Numerical experiments are carried out to validate the effectiveness of the proposed approach and to explore the prospects for future green reverse logistics.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• 제30권1호
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• pp.8-13
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• 2016

Public institutions should replace their luminaires with LED lighting by 2020 to save energy. Because the LED lighting installation rate in schools has not yet reached the legal goal, the ESCO program feasibility was investigated. The amount of electricity used, electric rates, times of use in classrooms and fluorescent lighting maintenance costs etc., as well as the elements of lighting maintenance were analyzed. In the case of schools, the lamp usage time was so short that the ESCO projects with only energy savings were impossible. In order to execute the ESCO projects, the maintenance cost savings by replacing an existing luminaire should be considered and the introduction of the relatively cheaper tube type LED lamp than the flat type LED luminaire was required.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 한국소성가공학회 2005년도 춘계학술대회 논문집
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• pp.419-422
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• 2005

Many process parameters have an effect on the auto-body panel forming process. A well-designed blank shape causes the material to flow smoothly, reduces the punch and yields a product with uniform thickness distribution. Therefore, the determination of an initial blank shape plays the important role of saving time and cost in the auto-body panel forming process. For these reasons, some approaches to estimate the initial blank shape have been implemented in this paper, the one-step approach by using a finite element inverse method will be introduced to predict the initial blank shape the developed program is applied to auto-body panel forming.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 한국소성가공학회 1999년도 춘계학술대회논문집
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• pp.62-65
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• 1999

To reduce the cost of finite element analyses for sheet forming a 3D hybrid membrance/sheel method has been developed to study the springback of anisotropic sheet metals. in the hybrid method the bending strains and stresses were analytically calculated as post-processing using incremental shapes of the sheet obtained previously from the membrane finite element analysis. To calculate springback a shell finite element model was used to unload the final shape of the sheet obtained from the membran code and the stresses and strains that were calculated analytically. For verification the hybrid method was applied to predict the springback of a 2036-T4 aluminum square blank formed into a cylindrical cup. the springback predictions obtained with the hybrid method was in good agreement with results obtained using a full shell model to simulateboth loading an unloading and the experimentally measured data. The CPU time saving with the hybrid method over the full shell model was 75% for the punch stretching problem.

• Korean Journal of Construction Engineering and Management
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• 제19권6호
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• pp.124-134
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• 2018

Despite the many advantages of modular housing, low preference for modular housing for consumers who are familiar with RC structure leads to high construction cost of modular housing. The cost of modular buildings is about 130% of that of RC structures, so it is urgent to secure economical efficiency of modular buildings. Therefore, in this study, after calculating the savings amount of modular housing by type of construction work, economic analysis was conducted from a long - term perspective. In order to carry out the research, the authors compiled and analyzed the material cost, labor cost, and expenses incurred by each type of work by reclassifying the statement of the modular housing into the factory production and the site installation. After that, Pareto diagrams were created to find a core work that is included in the cost ratio of about 80%, and selected it as a cost reduction subject. Based on the assumption that the market size of domestic modular housing is similar to the level of modular advanced countries such as Japan and European countries, six cost reduction methods were set up that reflects the characteristics of the modular construction method and used for the expert interviews. Cost saving potentials in percentage from the interview were converted to the amount of savings that can be achieved by each type of method when applying the method. Finally, the findings of the study are expected to suggest long-term directions for technical development for modular construction and cost savings.

• Information Systems Review
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• 제18권1호
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• pp.79-103
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• 2016

The Korean Army has to construct a system that will enable it to cope immediately with the flexible military relationships in Northeast Asia by systematizing and improving the efficiency of operations. These improvements include building a smart and strong army, concentrating on cost-effective combat skills, maximizing the utilization of private resources, and establishing a military structure based on information and technology. Accordingly, this study proposes solutions to solve the problems affecting the success of outsourcing in the defense industry. Unlike outsourcing in other government ministries, outsourcing in the national defense sector may be unrealistic because this strategy is related to the renovation project of the Ministry of the National Defense. In general, the objective of outsourcing in the defense industry, similar to other businesses, is to improve efficiency and not to reduce troops and national defense budget. Several factors, such as identification and security guarantee, risk reduction, cost saving, quality improvement, the reliability of enterprise, and professional technology, are necessary to ensure outsourcing success in the national defense sector. In terms of effectiveness, the improvement in service quality significantly influences outsourcing success in the national defense sector. Eventually, the national defense forces must be strengthened to prevent the provocative actions of North Korea and other threats by improving identification, sense of national security, and quality unlike the current outsourcing of the government, as well as emulating German GEBB or PMC, which utilizes social capital.