• 한국태양에너지학회 논문집
• /
• 제26권2호
• /
• pp.61-67
• /
• 2006

The use of the wind energy resource is a rapidly growing area world-wide. The number of installed units is continuously increasing, and therefore, it is important to respect and to deal with the impact of wind power generation system. From the view of an electric grid utility, there is a major problem with the impact of the wind system on the voltage of the electric grid, to which a turbine is connected. In this paper, it is investigated the voltage impact and transient state analysis on distribution line, with which wind power generation system is connected. Connections of wind power system usually occur to voltage drop due to reactive power absorption and sometime result in higher than nominal voltage.

• 전기학회논문지P
• /
• 제58권2호
• /
• pp.95-100
• /
• 2009

Recent advances in computer technology have brought more dependence on software to railway systems. Hence, the safety assurance of the vital software running on the railway system is very critical task and yet, not many works have been done. While much efforts have been reported to improve electronic hardware's safety, not so much systematic approaches to evaluate software's safety. In this paper, we suggested an automated analysis tool for S/W change impact in railway system, and presented its result of implementation. The analysis items in the implemented tool had referred to the international standards in relation to the software for railway system, such as IEC 61508 and IEC 62279. In these international standards, 'change impact analysis' for railway system S/W has to be required mandatorily. The proposed tool can be utilized at the assessment stage and also the software development stage.

• 소음진동
• /
• 제9권4호
• /
• pp.778-784
• /
• 1999

A method for obtaining the motion of an impact system whose primary and secondary system are composed of lumped masses, springs and dampers, and all the contacts are made through spring and damping elements is presented. The frequency response functions derived from the equations of motion and the impulse response functions obtained from the inverse Fourier transform of the derived frequency response functions are used for the calculation of the system responses. The procedure developed for the calculation of displacements and force time-histories was based on the convolution integrals of impulse response functions and forces applied to the systems. Time histories of displacements and contact forces are obtained for the case where a random excitation is applied to a point in the system. Impact statistics such as contact forces and the time between impacts calculated from those time histories is presented.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2001년도 추계학술대회논문집 II
• /
• pp.597-602
• /
• 2001

The structure of the human body has a limit to absorb the high-level-impact that occurs in shoulder-fired system. In other to solve this problem, short recoil system is applied to shoulder-fired system, and is verified experimentally, and then is performed analysis of parameters sensitivity, optimization of main part. According to the results, we developed A fundamental basis for buffering structure modeling that is operated by high level input in shoulder-fired system

• 한국수소및신에너지학회논문집
• /
• 제29권1호
• /
• pp.111-116
• /
• 2018

The environmental impacts of a 1 kW polymer electrolyte membrane fuel cell (PEMFC) system are quantitatively assessed by performing a Life Cycle Assessment (LCA) study. A PEMFC system produces electricity and heat simultaneously, so an appropriate allocation of associated inputs and outputs is performed between the electricity and heat produced. The environmental impacts of the PEMFC system on the impact categories such as global warming (GW), abiotic depletion (AD), acidification (AC), and eutrophication (EU) are assessed from the life cycle impact assessment. The impact indicator results of the impact assessment on these impact categories are obtained as $3.70E-01kg\;CO_2\;eq./kWh$, 1.86E-03 kg Sb eq./kWh, $4.09E-04kg\;SO_2\;eq./kWh$, and $1.88E-05kg\;PO_4{^{3-}}/kWh$, respectively. For all impact categories studied the most influential stage is the operation stage, which accounts for 98.8%, 98.7%, 70.3%, and 62.3% of the total impact on GW, AD, AC, and EU, respectively. For the impact categories of AD, AC, and EU, most of the environmental impacts during the operation stage is attributed to the production of city gas. However, for the impact category of GW, $CO_2$ emission from the reforming process of city gas is the main reason for the largest contribution of the operation stage to the total impact results.

• 대한공간정보학회지
• /
• 제21권1호
• /
• pp.45-52
• /
• 2013

환경영향평가 정보지원시스템은 환경영향평가 관련 정보의 다양화, 최신화 및 질적 향상, 그리고 평가서 및 협의 의견 등의 자료를 데이터베이스화를 통하여 평가서 작성의 기간단축 및 사회적 비용절감과 안정적인 서비스를 제공하여 사용자의 편이를 제공하여 환경평가제도 운영의 효율성을 극대화하기 위하여 추진되고 있다. 이 연구에서는 본 시스템의 지리정보서비스를 소개하고 사용자들의 편의성 향상과 서비스 지원범위 확대 등을 위하여 시스템 사용자의 설문조사를 통한 지리정보서비스의 활용성 개선방안을 제시하고자 수행하였다. 지리정보의 자료 업데이트 관련한 개선방안으로 환경공간정보의 자료수집, 구축, 그리고 활용을 위한 일원화된 인벤토리 구축을 위하여 데이터하우스의 단계별 유통 및 연계방안을 수립하여 제시하였다.

• 품질경영학회지
• /
• 제51권2호
• /
• pp.263-282
• /
• 2023

Purpose: This study aimed to examine the impact of FSSC 22000 food safety management system characteristics on the business performance of food-related companies and to verify the mediating effect of organizational capabilities in the relationship between them. Methods: To achieve this, a survey was conducted among employees of food companies in Seoul and the metropolitan area that have implemented the FSSC 22000 food safety management system, and the following main results were derived. Results: First, the FSSC food safety management system factors, such as measurement/analysis and improve- ment, documentation, management responsibility, and service and product realization, were found to have a significant positive (+) impact on organizational capabilities. The relative impact was in the order of measurement/analysis and improvement, documentation, management responsibility, and service and product realization. Second, organizational capabilities were found to have a significant positive (+) impact on business performance. Third, the FSSC food safety management system factors, such as measurement/analysis and improvement, management responsibility, resource management, and documentation, were found to have a significant positive (+) impact on business performance. The relative impact was in the order of measure- ment/analysis and improvement, management responsibility, resource management, and documentation. Fourth, the factors of management responsibility, resource management, measurement/analysis and improvement, and documentation, excluding resource management factors, were found to have a positive impact on business performance through the mediation of organizational capabilities. Conclusion: The results of this study may provide important implications for the implementation and efficient operation and management of the FSSC 22000 food safety management system in enhancing the business performance of food-related companies.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2002년도 학술대회지
• /
• pp.9-10
• /
• 2002

Human circulatory system between heart and tissue is not directly connected in normal condition but mandatory to go through the capillary system in order to fulfill its physiologic aim to deliver oxygen and nutrients, etc. to the tissue and retrieve used blood together with waste products from the tissue properly. When abnormal connection between arterial and venous system (AV fistula), these two circulatory systems respond differently to the hemodynamic impact of this abnormal connection between high pressure (artery) and low pressure (vein) system. Depending upon the location and/or degree (e.g. size and flow) of fistulous condition, each circulatory system exerts different compensatory hemodynamic response to this newly developed abnormal inter-relationship between two systems in order to minimize its hemodynamic impact to own system of different hemodynamic characteristics. Pump action of the heart can assist the failing arterial system directly to maintain arterial circulation against newly established low peripheral resistance by the AV fistula during the compensation period, while it affects venous system in negative way with increased venous loading. However, the negative impact of increased heart action to the venous system is partly compensated by the lymphatic system which is the third circulatory system to assist venous system independently with different hemodynamics. The lymphatic system with own unique Iymphodynamics based on peristaltic circulation from low resistance to high resistance condition, also increases its circulation to assist the compensation of overloaded venous system. Once these compensation mechanisms should fail to fight to newly established hemodynamic condition due to this abnormal AV connection, each system start to show different physiologic ${\underline{de}compensation}$ including heart and lymphatic system. The vicious cycle of decompensation between arterial and vein, two circulatory system affecting each other by mutually negative way steadily progresses to show series of hemodynamic change throughout entire circulation system altogether including heart. Clinical outcome of AV fistula from the compensated status to decompensated status is closely affected by various biological and mechanical factors to make the hemodynmic status more complicated. Proper understanding of these crucial biomechanical factors iii particular on hemodyanmic point of view is mandatory for the advanced assessment of biomechanical impact of AV fistula, since this new advanced concept of AY fistula based on blomechanical information will be able to improve clinical control of the complicated AV fistula, either congenital or acquired.

• 한국공작기계학회:학술대회논문집
• /
• 한국공작기계학회 2000년도 춘계학술대회논문집 - 한국공작기계학회
• /
• pp.355-360
• /
• 2000

There are many changed while a design is completed. Therefore, if the impact of the design changes is estimated, it may result in the improvement of design efficiency. But, the design changes have various types and affect other parts of the design system. Hence, it is difficult to deal with design changes directly. The purpose of this research is to develop a systematic change propagation tracing algorithm and a method of change impact analysis and then, to implement a change impact analysis system. Process based design is set up for the field of this research. Also the design, composed of design parameters and constraints, is set up for the subject of the research. Change propagation tracing algorithm traces change propagation based on the following concept : If the design parameters are changed, other parameters within the constrains including them may be changed. Using the result of change propagation tracing algorithm, changeable parameters, constraints and tasks can be found. The method of change impact analysis, to calculate change impact value from this changeable tasks, is developed. Change propagation tracing algorithm and the method of change impact analysis are implemented into change impact analysis system and it is applied to the redesign of 2 stage gear drives. It can support different kinds of design activities systematically. especially, at the redesign step, where many design change alternatives exist, change impact value of each alternative exist, change impact value of each alternative is calculated and design change is performed toward direction to minimize the impact of design change. Consequently, it is expected to improve the efficiency of the whole design.

• Journal of the Korean Wood Science and Technology
• /
• 제30권3호
• /
• pp.75-84
• /
• 2002

In order to find out impact insulation properties, various types of current radiant floor heating systems and light-framed floors that are used in light-framed residential buildings were evaluated for two types of impact sources at the same time. Sound Pressure Level (SPL) was different from each impact sources for those spectrum patterns and peaks. In case of light-framed floor framework, the excitation position and the assumed effective vibrating area have effects on sound pressure level but it is not considerable, and Normalized SPL was reduced for each frequency by increasing the bending rigidity of joist. The mortar layer in the radiant heating system had relatively high density and high impedance, therefore, it distributed much of the impact power when it was excited, and reduced the Normalized SPL considerably. Nevertheless, Increasing a thickness of mortar layer had little influence on SPL. Ceiling components reduced the sound pressure level about 5~25 dB for each frequency. Namely, it had excellent sound insulation properties in a range from 200 to 4,000 Hz frequency for both heavy and lightweight impact sources. Also, there was a somewhat regular sound insulation pattern for each center frequency. The resilient channel reduced the SPL about 2~11 dB, irrelevant to impact source. Consequently, current radiant floor heating systems which were established in light-framed residential buildings have quite good impact sound insulation properties for both impact sources.