• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.1229-1234
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• 2001

The bottom slab of Inchon LNG in-ground #213 tank is designed as a massive structure witch has a large depth and section. The purpose of this study is to determine the optimum mix design having good workability and low hydration heat for bottom slab concrete and to control the actual concrete quality in site. For this purpose, we select the optimum mix design used ternary blended cement(furnace slag cement＋fly ash) and design factors. As test results of actual application, we have finish placing the bottom slab concrete of 23,180㎥ during 68hours with good success and obtain the good quality of fresh and hardened concrete including slump, air contents, no-segregation, compressive strength and low hydration heat in actual data. All test results are satisfied with our specifications for bottom slab concrete and we cut costs as the use of ternary blended cement and the reduction of placing hours.

• Resources Recycling
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• v.7 no.5
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• pp.3-12
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• 1998

The most recent research in precious metal processing is found in the increasing use of heap leaching for the extraction of gold from low grade ores and tailing dumps because heap leaching has several advantages compared to traditional milling. They include simplicity, lower capital and operating costs, faster starter-up time and environmental safety. In this paper, an attempt has been made to provide an overview of important factors involved in the implementation of heap leaching technology as a vehicle for gold extraction from its low grade ores. Brief discussions of the various important elements to this process has been made to ascertain the heap leaching characteristics, such as heap leaching chemistry, natural factors, ore preparation, heap and pad construction, solution collection system, pond system, metal extraction, and economical consideration.

• International Journal of Quality Innovation
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• v.10 no.2
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• pp.57-76
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• 2009

Although many adherents openly praise the importance of quality management practices (QMP) in organisations, others have identified significant costs and implementation obstacles. Some recent studies showed that QMP have failed due to the ignorance of quality cultures. How to improve the success rate of QMP in organisations has become a critical issue both in the academy and in practice. This paper discusses the common enablers of and cultural impacts on QMP. It explores the dimensions of national versus organisational culture, and identifies the main features of four quality culture models as advocated in the literature in relation to facilitating QMP in organisations. It was found that flat structures, decentralised functions, empowerment, flexibility, innovation, limited rules and regulations and teamwork favor the QMP implementation. For facilitating culture changes for QMP, values associated with low power distance, low uncertainty avoidance and collectivism would have to be nurtured. Further research is needed to incorporate the findings and develop a practical quality culture approach for real applications in industry.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.119.1-119.1
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• 2011

Since Gratzel et al. reported the first efficient dye-sensitized solar cells(DSSCs) in 1991, they have attracted much attention due to their relatively high power conversion efficiency and potentially low cost production. To date, high performance and good stability of DSSC based on Ru-dyes as a photosensitizer had been widely addressed in the literatures. However, the Ru-dyes are facing the problem of manufacturing costs and environmental issues. In order to obtain even cheaper photosensitizers for DSSC, the metal-free organic photosensitizers are strongly desired. The metal-free organic dyes offer superior molar extinction coefficients, low cost, and diverse molecular structures as compared to the conventional Ru-dyes, In this work, we have studied on the synthesis and characterization of the organo dendritic dyes containing different number of electron acceptor moieties in a molecule.

• Journal of the Korean Professional Engineers Association
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• v.42 no.5
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• pp.41-45
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• 2009

The last century of lighting has been dominated by incandescent, fluorescent and high-intensity discharge(HID)light sources. In the late 1970's, after green LEDs were invented, Dr. Ching Tang at Eastman Kodak discovered that sending an electrical impulse through carbon compound caused such material glow. Present day LED commercial packages have reached 100 lm/W, comparable to the efficacies of fluorescent and certain HID lamps. LED products available today are market as "Green-Industry" but actually low light output compared to typical light sources. The combination of high price and low light output make them a poor replacement for current technology. It is very important to compare new LED products to the most efficient conventional technology that could be used for any specific application. As LED technology advances, costs decrease, and efficiency improves, LEDs will build market share in the general illumination market.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.5
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• pp.582-594
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• 2016

Various test data compression techniques have been developed to reduce the test costs of system-on-a-chips. In this paper, a scan chain reordering algorithm for code-based test data compression techniques is proposed. Scan cells within an acceptable relocation distance are ranked to reduce the number of conflicts in all test patterns and rearranged by a positioning algorithm to minimize the routing overhead. The proposed method is demonstrated on ISCAS '89 benchmark circuits with their physical layout by using a 180 nm CMOS process library. Significant improvements are observed in compression ratio and test power consumption with minor routing overhead.

• Journal of the Korean Institute of Rural Architecture
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• v.1 no.3
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• pp.27-34
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• 1999

The purpose of this study was to provide basic information on the rural house planning through the research on the use of the standard plans, architectural characteristics, importance of the planning points and housing satisfaction of the residents. 25 rural households scattered around Chungchong provinces-south and north- were surveyed for this study through the questionnaire method. The results of this study were as follows. The importance considered first was the low construction costs, and therefore the standard plans were not fully acknowledged and commonly used. Most real plans are the single-floor houses with 3 rooms, having 25-30 pyong magnitude. The planning points stressed highly were the storage space, convenience of the plan and size of the living room. Housing satisfaction level was high on direction of the facade, size of the living room and position of the bath/washing room, but low for the storage space.

• KDI Journal of Economic Policy
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• v.37 no.3
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• pp.1-30
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• 2015

Based on a quantitative, heterogeneous agent general equilibrium model, we compute the optimal tax rates for labor and capital incomes for the Korean economy. According to our model, a more progressive income tax schedule along with a higher capital tax rate can increase average welfare by as much as 0.86% of permanent consumption. Approximately 64% of house-holds, those with low assets and low productivity, are better off when a more progressive optimal tax schedule is adopted. Despite the potentially significant welfare gains, our calculation should be interpreted with caution because our benchmark model does not take into account possible capital outflows or the increased administrative costs associated with high taxes.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.283-283
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• 2010

Smart street light controller is a product with advance micro controller base for energy saving in conventional street lighting systems. Intelligent Street light controller are specially developed for automation and energy saving in conventional street light systems and lighting systems. It is so designed that it operates on sunrise & sun set timings according to longitude of particular location with facilitate to set month wise civil twilight timings to cope up with all seasons. Dimming (Power down) mode selection switch on/off at fixed times with relay or contactor. Night dimming, staggering and intelligent control reduces burn hours and increases the lifetime of lamps with about 30% and low annual operating cost type base are among the most inexpensive wireless technologies available. Low initial costs As PLC wireless, there is no need to establish cable connection.

• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2310-2312
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• 2004

In Korea Electric Power Corporation (or KEPCO), several Demand-Side Management (or DSM) program have been carried out to effectively meet electric power demand at least costs by modifying customers electricity use patterns. As one of them, KEPCO applies low-priced night thermal-storage power service for heat appliances to facilitate efficient use of power facilities by shifting relatively high daytime demands to night hours to build loads during the off-peak periods. In the market of heat-storage type water-heater, electric water-heater has been mostly used, but it has low energy efficiency and needs high capacity electric equipments. So in order to replace these electric water heaters, 15 HP air-source heat pump water heater is developed in Korea Electric Research Institute (or KEPRI). This paper shows that measurement system for performance testing of heat pump water heater is established and heating capacity and performance is analyzed and measured for out-door environmental change.