• Title/Summary/Keyword: IT Efficiency

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Analysis of a Refrigeration Cycle Driven by Refrigerant Steam Turbine (냉매증기터빈에 의해 구동되는 냉동사이클의 해석)

  • 정진희
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.14 no.10
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    • pp.801-810
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    • 2002
  • We have analyzed a combined cycle employing refrigerant Rankine cycle and simple refrigeration cycle with one working fluid. Although this cycle shows promising aspects such as simplicity, it does not have a good efficiency to compete with the other existing technologies because of high temperature at the exit of the turbine. However, by introducing a recuperator, it is found that the cycle efficiency can be improved up to the level much higher than other technology's efficiency.

A Novel Recovery Circuit of a Leakage Inductance Stored Energy in Flyback Converter (플라이백 컨버터에서 누설인덕턴스 저장에너지의 새로운 회복회로)

  • Jung, Yong-Chae
    • Proceedings of the KIPE Conference
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    • 2005.07a
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    • pp.526-528
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    • 2005
  • Nowadays, more than ever before, many researchers are paying attention to raising the efficiency of a Power converter. In Flyback converter, the resistor of RCD snubber consumes the stored energy in leakage inductor. It play a role in degrading the overall system efficiency Thus, In this paper, a novel energy recovery circuit of Flyback converter is proposed to improve the efficiency. The operational principle of the proposed circuit is explained in detail. And, it is verified through the simulation results.

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The Efficiency Analysis of CRM System in the Hotel Industry Using DEA (DEA를 이용한 호텔 관광 서비스 업계의 CRM 도입 효율성 분석)

  • Kim, Tai-Young;Seol, Kyung-Jin;Kwak, Young-Dai
    • Journal of Intelligence and Information Systems
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    • v.17 no.1
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    • pp.91-110
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    • 2011
  • This paper analyzes the cases where the hotels have increased their services and enhanced their work process through IT solutions to cope with computerization globalization. Also the cases have been studies where national hotels use the CRM solution internally to respond effectively to customers requests, increase customer analysis, and build marketing strategies. In particular, this study discusses the introduction of the CRM solutions and CRM sales business and marketing services using a process for utilizing the presumed, CRM by introducing effective DEA(Data Envelopment Analysis). First, the comparison has done regarding the relative efficiency of L Company with the CCR model, then compared L Company's restaurants and facilities' effectiveness through BCC model. L Company reached a conclusion that it is important to precisely create and manage sales data which are the preliminary data for CRM, and for that reason it made it possible to save sales data generated by POS system on each sales performance database. In order to do that, it newly established Oracle POS system and LORIS POS system concerned with restaurants for food and beverage as well as rooms, and made it possible to stably generate and manage sales data and manage. Moreover, it set up a composite database to control comprehensively the results of work processes during a specific period by collecting customer registration information and made it possible to systematically control the information on sales performances. By establishing a system which unifies database and managing it comprehensively, impeccability of data has been greatly enhanced and a problem which generated asymmetric data could be thoroughly solved. Using data accumulated on the comprehensive database, sales data can be analyzed, categorized, classified through data mining engine imbedded in Polaris CRM and the results can be organized on data mart to provide them in the form of CRM application data. By transforming original sales data into forms which are easy to handle and saving them on data mart separately, it enabled acquiring well-organized data with ease when engaging in various marketing operations, holding a morning meeting and working on decision-making. By using summarized data at data mart, it was possible to process marketing operations such as telemarketing, direct mailing, internet marketing service and service product developments for perceived customers; moreover, information on customer perceptions which is one of CRM's end-products could feed back into the comprehensive database. This research was undertaken to find out how effectively CRM has been employed by comparing and analyzing the management performance of each enterprise site and store after introducing CRM to Hotel enterprises using DEA technique. According to the research results, efficiency evaluation for each site was calculated through input and output factors to find out comparative CRM system usage efficiency of L's Company four sites; moreover, with regard to stores, the sizes of workforce and budget application show a huge difference and so does the each store efficiency. Furthermore, by using the DEA technique, it could assess which sites have comparatively high efficiency and which don't by comparing and evaluating hotel enterprises IT project outcomes such as CRM introduction using the CCR model for each site of the related enterprises. By using the BCC model, it could comparatively evaluate the outcome of CRM usage at each store of A site, which is representative of L Company, and as a result, it could figure out which stores maintain high efficiency in using CRM and which don't. It analyzed the cases of CRM introduction at L Company, which is a hotel enterprise, and precisely evaluated them through DEA. L Company analyzed the customer analysis system by introducing CRM and achieved to provide customers identified through client analysis data with one to one tailored services. Moreover, it could come up with a plan to differentiate the service for customers who revisit by assessing customer discernment rate. As tasks to be solved in the future, it is required to do research on the process analysis which can lead to a specific outcome such as increased sales volumes by carrying on test marketing, target marketing using CRM. Furthermore, it is also necessary to do research on efficiency evaluation in accordance with linkages between other IT solutions such as ERP and CRM system.

An Efficient Message Management Scheme in Game Engine (게임엔진에서의 효율적인 메시지 관리 기법)

  • Lee, Sang-Wan;Kim, Hye -Young
    • Journal of Korea Game Society
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    • v.8 no.2
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    • pp.77-84
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    • 2008
  • Game engine, materialized by a library or a shape of the module, is providing many ability for developing game. Because of the high cost of developing game, game engine plays a big role on game developing urea by how it provide it's efficiency. In other words, the message scheme, which occur often while carrying out the game, highly affect on how fast it manage, its efficiency, and system's efficiency. Also, it is one of the important urea that needed to be considered while developing the game engine. In this paper, we suggest managing the message scheme technique by Lua script language, proving its suggested technique by developing $O_2$ engine itself, and analyzing it's capacity in order to show its efficiency.

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The Estimation Method and Application of UV-cut effect in Lens (렌즈에서 UV 차단효과의 평가방법 및 적용)

  • Kim, Yong-Geun
    • Journal of Korean Ophthalmic Optics Society
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    • v.6 no.1
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    • pp.107-110
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    • 2001
  • In order to estimate the UV-A line's cut efficiency it lens, it was measured the light transmittance in the 320~400nm wavelength regions. We obtained the area to integrate the light transmittance of standard CR-39 and sample in the 320~400nm wavelength regions and established ${\alpha}$, ${\beta}$ of UV-A line's cut efficiency by contrast its area. We obtained the absolute cut efficiency ${\alpha}$ CR=0.59 value of CR-39 Lens, and if ${\alpha}$ was the absolute cut efficiency value of the lens to estimate UV-A cut effect, the relative cut efficiency ${\beta}$ was $1.69{\alpha}$. It was obtained the absolute and the relative UV exclusion index through each $a=(1-{\alpha}){\times}100%$, $b=(1-{\beta}){\times}100%$.

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Locally Made Liquor(LML) Industry Status and Development Plan Using a Scale Efficiency Analysis

  • Lee, Dongso;Choi, Jong-Woo;Huh, Duk
    • The Journal of Industrial Distribution & Business
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    • v.8 no.5
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    • pp.43-52
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    • 2017
  • Purpose - The domestic liquor market is steadily increasing, but locally made liquor markets remain stagnant. The market opening due to the FTA and westernized eating habits are expanding the consumption of imported liquor by Koreans and the demand for beer and soju is still high. Therefore, we analyzed the scale efficiency of Korean locally made liquor companies. Research design, data, and methodology - Based on a translog-cost function, a scale efficiency analysis was conducted using the government's information survey on the liquor industry. Data from 541 liquor companies analyzed from 2013 to 2014 were used for analysis. Results - As a result of the scale efficiency analysis, the average sales of the mid-sized locally made liquor companies is 171 million won, but the appropriate sales amount is 1 million won. It is estimated that there is a need to increase sales. Conclusions - The gap between the actual sales and the appropriate sales of mid-sized locally made liquor companies with 3~10 employees is larger, so it is necessary to reduce the average cost by increasing the sales of locally made liquor companies. In order to do so, it is necessary to acquire customer strategies such as product differentiation, advertising and publicity.

Characteristic of wireless power transmission S-Parameter for a superconductor coil

  • Jeong, In-Sung;Jung, Byung-Ik;Choi, Hyo-Sang
    • Progress in Superconductivity and Cryogenics
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    • v.17 no.1
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    • pp.36-39
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    • 2015
  • Many studies are being conducted to implement wireless charging, for example, for cellular phones or electronic tooth brushes, via wireless power transmission technique. However, the magnetic induction method had a very short transmission distance. To solve this problem, the team of Professor Marin Soljacic proposed a magnetic resonance system that used two resonance coils with the same resonance frequency. It had an approximately 40% efficiency at a 2m distance. The system improved the low efficiency and short distance problems of the existing systems. So it could also widen the application range of wireless power transmission. Many studies on the subject are underway. In this paper, the superconductor coil was used to improve the efficiency of magnetic resonance wireless power transmission. The resonance wireless power transmission system had a source coil, a load coil, and resonance coils (a transmitter and a receiver). The efficiency and distance depended on the characteristics of the transmitter and receiver coils that had the same resonance frequency. Therefore, two resonance coils were fabricated by superconductors. The current density of the superconductor was higher than that of the normal conductor coil. Accordingly, it had a high quality-factor and improved efficiency.

Fuel Efficiency and Emission Characteristics on Aged Three-way Catalyst of LPG Vehicle (LPG 차량의 삼원촉매 노후화에 따른 연비 및 배출가스 특성)

  • Kang, Minkyung;Kwon, Seokjoo;Kim, Kiho;Seo, Youngho
    • Journal of ILASS-Korea
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    • v.21 no.3
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    • pp.137-143
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    • 2016
  • The LPG vehicles are being operated by commercial purposes generally such as taxis. Most of taxis have a long-mileage and a harsh driving pattern. These properties may accelerate aging of the three-way catalysts much faster than the passenger vehicles. Because of this background, it was analyzed the test result of fuel efficiency and emissions on the LPG-fueled light duty vehicle. It was selected for a LPG vehicle of ULEV level to measure the fuel efficiency and emissions of the aged three-way catalysts. And the aged three-way catalysts which was driven about 300,000km and 550,000km replaced on the test vehicle in consecutive order. As a result, The aged three-way catalysts generally had no effect on fuel efficiency result, and harmful exhaust emissions had been shown to increase in most of the test mode, even though it satisfied the regulation value on most test modes.

Optimization of valve events in a 4 cycle reciprocating engine using measured intake and exhaust port pressures (4사이클 왕복동식 엔진에 있어서 흡배기 변동압 측정치를 이용한 흡기효율 최적화 컴퓨터 시뮬레이션)

  • 오세종;진영욱;정재화
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.13 no.3
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    • pp.500-507
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    • 1989
  • The improvement of volumetric efficiency of air charging into combustion chamber is a primary requirement to obtain better mean effective pressure of an engine. Since parameters such as the air resistances in intake and exhaust flow passages, valve lift and valve timing influence greatly to the volumetric efficiency, it is very convenient and time saving if we can optimize these parameters by computation before we enter into long time fact finding engine tests. In this study we have developed a semi-empirical engine simulation program for the determinations of intake and exhaust valve timings, valve lifts, intake and exhaust port diameters in order to obtain highest volumetric efficiency. In this computation it requires only the measured variational pressures in intake and exhaust port. Using these variational pressures as an input data for our simulation program, we can calculate volumetric efficiency more accurately and can save computing time drastically. To confirm the validity of our simulation program we have made engine operation test in parallel and taken the experimental data. Comparing the computation result with the experimental data obtained through real engine test it has shown only the difference of 3%.

The Cost Efficiency Analysis of JeollaNamdo Food Industry (전라남도 식품업체의 비용 효율성 분석)

  • Qing, Cheng Lin;Na, JuMong;Chang, Seog Ju;Im, Chang Uk
    • Journal of Korean Society for Quality Management
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    • v.43 no.4
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    • pp.533-544
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    • 2015
  • Purpose: The purpose of this study is to analyze the cost efficiency of food industry in JeollaNamdo. And this study is focused on the correlation between the economic efficiency of food industry and its cost efficiency, based on the analysis of 372 food companies' data in JeollaNamdo in 2012. Methods: DEA cost minimization is the measurement of the cost efficiency of JeollaNamdo food industry in 2012. In this study, the CCR and BBC models have been employed to analyze the decomposing cost efficiency-technical efficiency, allocative efficiency, and scale efficiency respectively. And the Spearman rank correlation and Wilcoxon signed rank test also have been employed to check the correlation and difference between the ranking orders based on the efficiency scores respectively. Results: For the CCR model, mean cost efficiency was found to be 0.084(0.54 for allocative efficiency and 0.19 for technical efficiency). For the BCC model, mean cost efficiency was found to be 0.252(0.453 for allocative efficiency and 0.564 for technical efficiency). Average scale efficiency was found to be 0.38. In analyzing the results, this study argues that the optimal way to improve cost efficiency is by reducing inputs proportionally and changing their combination. Conclusion: The efficiency scores of the two models show high correlation, whereas, the differences between them are also found to be significant. Hence, it should be cautious to select a suitable model when we do the research.