• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.127-132
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• 2000

This paper describes a 3-phase Line-Interactive APF system and analyzes its operating characteristics considering LC Filter output characteristics. Topology of APF is similar to that of Off-Line UPS in the point of parallelly operating inverter system. So it is possible to be multi-functioned active compensating system according to power condition. Likewise this actively operating system from APF to UPS and vice versa is often to be called Line-Interactive system. And more than that Line-Interactive system needs precise design of LC filter on converter output side to make this system fully operate in both APF and UPS modes. The problem in this point is how to design LC Filter to be contented with two different system characteristics so this paper analyzes this problem and proposes its design procedures. Then suggested filter design is verified to be contented by the simulations and experimental results

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 춘계학술발표대회 논문집
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• pp.209-213
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• 2009

This article interprets the operating characteristics of the photovoltaic system during the winter and spring seasons, and based on the theoretical knowledge, analyzes the operational characteristics and the power electricity during the tentative application and operation of this system. Through the long-term measurement of the sunshine time and collection of the data related to this, we examine the study of graphic presentation and monitoring systems.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2004년도 유체기계 연구개발 발표회 논문집
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• pp.160-165
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• 2004

MPA (Multi-Point Averaging) flow element is a new type of differential pressure (DP) flow-sensing device that was developed by Seojin Instech to improve the operating characteristics of the conventional Averaging Pilot Tube (APT) flow elements. Operating characteristics of a flowmeter in general can be defined in terms of measurement accuracy and range. Improvement of accuracy and expanding the range of flow measurement were the two main objectives of the development. To achieve these dual objectives several upstream and downstream pressure-sensing holes were placed in MPA flow element. During the course of the development it was found that certain arrangements of the pressure-sensing holes improved measurement accuracy but did not expand operating flow range of Averaging Pilot Tubes. Development tests were performed with water between Reynolds number of 50,000 and 1,000,000 in the four-inch test line at the Alden Research Laboratory, U.S.A. Purpose of this paper is to present the relationship between the various locations of the pressure-sensing holes and the performance characteristics of MPA flow element. Furthermore, the operating characteristics of the best performing MPA are compared with those of typical orifice and APT.

• 지역사회간호학회지
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• 제16권3호
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• pp.351-359
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• 2005

Purpose: To find the factors of subjective musculoskeletal symptoms associated with the general characteristics and tasks of operating room nurses (OR nurses) and then to use the factors as basic information for preventing and managing musculoskeletal symptoms in OR nurses. Method: This study was an exploratory research. Data were collected using a self-report questionnaire from OR nurses working at 8 polyclinics in Korea during the period from July 26 2004 to August 19 2004. The questionnaire contains 7 questions on general characteristics and 18 questions on tasks in the operating room. Result: 187 (75.1%) nurses said they 'had' subjective musculoskeletal symptoms. Statistically significant differences were observed according to clinical career, career as an OR nurse, skillfulness, satisfaction with tasks in the operating room, perception on suitable treatment, care of symptoms by the hospital. weight of hospital linen and weight of a basic operation set (p<.05). Conclusion: Musculoskeletal symptoms complained of by OR nurses were significant. This may cause difficulties in nursing tasks in the operating room. Thus, various arrangements should be made for OR nurse with subjective musculoskeletal symptoms at the early stage.

• 한국병원경영학회지
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• 제26권3호
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• pp.13-27
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• 2021

Purpose: We examined the relationship between operating income and volume of medical services provided at general hospitals in 2018 according to characteristics of general hospitals and measured as operating income(net income) and volume(adjusted inpatient days) covered or non-covered by National Health Insurance(NHI). Methodology: Finance data from income statement reports in 212 general hospitals and the national health insurance claim data of these hospitals were used. The characteristics of the general hospital were divided into structural, operational, financial, and patient aspects. Operating income and volume were divided into covered and non-covered by NHI. Findings: The results showed high volume hospitals tended to be more profitable than low volume hospitals, especially in non-covered services. Operating income was more likely to be sensitive to non-covered services volume than to covered services volume. Practical Implications: It is necessary to understand the volume of services in non-covered, in order to obtain reliable cost information to be used for the fee schedule. Researches on small size hospitals(<160 beds) are needed, with a large variation in the volume of services and a strong tendency to compensate for the loss in the covered part in non-covered part.

• 산업경영시스템학회지
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• 제33권4호
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• pp.10-22
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• 2010

The first full-scale u-City operation has started in Dongtan u-City. As local cities take over and operate the u-City, unexpected issues arise such as securing the budget of operating costs and self-providing the costs with business models utilizing the u-City assets. The paper presents a strategy for solving these issues. The strategy provides a foundation(infrastructure) for long-term operation models which may reduce the long-term operating costs. In order to establish the economic operating framework of u-City, suggested are some cost-reduction models based on the operating costs structure. For each model, a base framework with comparative analysis of operating costs is provided. With these models, each u-City may select a relevant model according to the characteristics of it. We hope that the framework provides the foundation for efficient and sustainable u-City operations.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.499-500
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• 2007

The various sensor nodes operating in Ubiquitous Sensor Network environment require the tiny Operating System different from the existing pc-type operating system because of their characteristics. Also Sensor Network operating system needs to support the rapid event handling which sensor node must implement. In this paper, we overcome the drawbacks of the existing sensor network operating system and propose the new kernel which is designed to assist developer to construct event-central operating system entirely. We also evaluate the performance of the super tiny sensor network operating system based on proposed kernel, comparing with that of the existing sensor network operating system.

• 한국수소및신에너지학회논문집
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• 제4권1호
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• pp.21-30
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• 1993

The operational characteristics of a metal hydride heat pump system are strongly dependent on the amound of hydrogen gas transferred by hydriding and dehydriding reactions between the reactors under dynamic conditions. A new metal hydride heat pump combined with hydrogen compressor was constructed and the dependency of its operating conditions on such as cycle time, amount of hydrogen to be transferred between two reacting metal hydride reactors, operating temperature, and heat transmission characteristics of the reactors was investigated to find the optimum operating efficiency. These conditions were also evaluated in connection with the cooling output and hydrogen compressor connected to the system in order to enhance the total efficiency.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 디스플레이 광소자분야
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• pp.206-209
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• 2004

We investigated response characteristics of liquid crystal display(LCD) with different operating mode of nematic liquid crystals (NLCs) such as $45^{\circ}$twist nematic (TN), $67.3^{\circ}$TN and ECB(electrical controlled birefringence) on a rubbed polyimide (PI) surface. The three kinds of LCD operating mode obtain stable EO performance. Low transmittances of the $45^{\circ}$TN and $67.3^{\circ}$TN cell on the rubbed PI surface were achieved by using low cell gap d. The fast response time of ECB cell among the three kinds of LCD operating mode was measured.

• Journal of Advanced Marine Engineering and Technology
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• 제17권4호
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• pp.11-19
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• 1993

The experimental study was carried out to investigate the stability and the performance characteristics of the aero-valved pulsating combustion system with maximum operating capacity of 60KW. The effect of geometry of combustion system on the stable condition, the flammability limit, the total pressure oscillation amplitude, and the operating frequency can be identified, and the maximum turn-down-ratio is obtained up to 3.3. The total pressure oscillation amplitude can be controlled by tunning the length of the air inlet pipe. The empirical equation with which the operating frequency can be approximated is proposed and the discrepancy is within 5%. The volumetric efficiency is identified to be one of the important parameters determining the upper flammability limit and the maximum value of which is approximately 22%.