• Journal of Power Electronics
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• 제17권5호
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• pp.1244-1255
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• 2017

The space vector pulse width modulation (SVPWM) technique is a popular PWM method for medium voltage drive applications. Conventional SVPWM (CSVPWM) and bus clamped SVPWM (BCSVPWM) are the most common SVPWM techniques. This paper evaluates the performance of various advanced BCSVPWM strategies in terms of their harmonic distortion and switching loss based on a uniform frame work. A uniform frame work, pulse number captures the performance parameter variations of different SVPWM strategies for various number of samples with heterogeneous pulse numbers. This work compares different advanced BCSVPWM techniques based on the modulation index and location of the clamping position (zero vector changing angle ) of a phase in a line cycle. The frame work provides a fixed fundamental frequency of 50Hz. The different BCSVPWM switching strategies are implemented and compared experimentally on a 415V, 2.2kW, 50Hz, 3-phase induction motor drive which is fed from an IGBT based 2 KVA voltage source inverter (VSI) with a DC bus voltage of 400 V. A low cost PIC microcontroller (PIC18F452) is used as the controller platform.

• 한국지능시스템학회논문지
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• 제23권3호
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• pp.238-243
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• 2013

본 논문에서는 이족 보행 로봇을 위한 무릎 및 힙 관절의 일 특성을 분석하고자 한다. 이를 위하여 컴플라이언스 특성의 발을 갖는 이족 로봇 다리 메커니즘을 대상으로 전형적인 보행 패턴을 고려한다. 또한 딱딱한 지면과 접촉하는 로봇 발 공간으로부터 다리 관절 공간으로 전파되는 토오크 특성을 확인하고, 보행에 따라 관절 공간에 누적되는 일 특성을 제시한다. 결과적으로, 이러한 분석이이족 로봇의 보행에서 발과 지면의 물리적인 접촉에 의한 다리 메커니즘의 피로 정도를 파악하는데 있어서 유용하고, 적절한 신발 착용 등에 의한 로봇 발 공간에서의 컴플라이언스특성 개선에 활용될 수 있음을 보인다.

• Nuclear Engineering and Technology
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• 제49권6호
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• pp.1125-1134
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• 2017

In this paper, we present a new multilevel in space and energy diffusion (MSED) method for solving multigroup diffusion eigenvalue problems. The MSED method can be described as a PI scheme with three additional features: (1) a grey (one-group) diffusion equation used to efficiently converge the fission source and eigenvalue, (2) a space-dependent Wielandt shift technique used to reduce the number of PIs required, and (3) a multigrid-in-space linear solver for the linear solves required by each PI step. In MSED, the convergence of the solution of the multigroup diffusion eigenvalue problem is accelerated by performing work on lower-order equations with only one group and/or coarser spatial grids. Results from several Fourier analyses and a one-dimensional test code are provided to verify the efficiency of the MSED method and to justify the incorporation of the grey diffusion equation and the multigrid linear solver. These results highlight the potential efficiency of the MSED method as a solver for multidimensional multigroup diffusion eigenvalue problems, and they serve as a proof of principle for future work. Our ultimate goal is to implement the MSED method as an efficient solver for the two-dimensional/three-dimensional coarse mesh finite difference diffusion system in the Michigan parallel characteristics transport code. The work in this paper represents a necessary step towards that goal.

• 한국가구학회지
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• 제27권2호
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• pp.154-163
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• 2016

In today's knowledge economy, various schemes are being devised in order to attain knowledge and understanding in the most effective ways possible. In an office environment, spatial concepts that encourage 'smart working' is becoming more prevalent; therefore allocating of space according to the types of work being performed, ways to maximise the work efficiency, and furniture arrangement to accelerate liaison among the users are being carefully considered. Especially in a space where its members are encouraged to communicate and collaborate, the furniture within that space need to be attractive and practical for its users, as well as efficient and effective for the firm the service is being provided for. In this study, we aim to offer furniture design service that satisfies such demands of the present time. Thus, instead of merely following a standard design process in which one approaches a project from design planes to an outcome, various aspects of the working environment will be considered such as the relationship between the space and the users, their needs, and the features of work being performed within the space. After attentive research and analysis, the results will be put into production from the user's point of view in mind. This study is intended to propose furniture design that embodies the characteristics of integrated working environment that can facilitate efficient use of the limited working space, productivity among the users, and promoting valuable corporate culture.

• 조형예술학연구
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• 제6권
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• pp.267-287
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• 2004

The study of a new expression within Korean ink painting that meets the demands of the times has continued, resulting in various expressions with acrylics, handycoat, objects and installations, crossing over from traditional Korean painting techniques. A 'margin' was both a very important space and esthetical matter that expresses 'Ki', 'Distance', and 'Omission' in traditional sense when addressing Korean ink painting Its expression methods and concepts, however, have changed today. A 'margin' through Montage technique can be a significant example in understanding the expression methods of today's Korean ink painting. This is because the margins in Montage make the meaning of the work various and flourished and deeply construct the surface with a double-layered structure, instead of using a single layer. These 'margins' created by Montage are spaces where different images conflict, divide and continue with each other and where a reconciliation between different spaces is accomplished. Furthermore, they establish more vitality and truthfulness to life through both the images conflict and reconciliation. After the adoption of Post-modernism Art in Korean ink painting, the characteristics of the 'margin' in Montage style by the division of surface are an 'acceptant's participatory imaginative space'; where viewers fill the margins with their imaginations ; an 'abandoned space' ; where unnecessary parts are deleted for more live surface ; and a 'strategic space', where the work enriches the structure and contents of surface by using margins strategically.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.482-484
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• 2005

The Modulation Transfer Function (MTF) is commonly used to characterize the spatial quality of imaging systems. This work is the attempt to measure the MTF at Nyquist frequency of the satellite imaging system what has 1m spatial resolution for KOMPSAT-2 image using the edge function. Artificial tarp targets are used in this study. A type of this tarp edge consists of two adjacent uniform bright and dark sides commonly used to test the performance of an optical system in edge function. The results from this work demonstrate the potential applicability of this method to estimate the response characteristics for KOMPSAT-2 that is scheduled to be launched.

• 한국식품조리과학회지
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• 제11권5호
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• pp.456-462
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• 1995

The work environment and 20 influencing variables in 20 conventional hospital foodservice systems were examined. Twenty hospitals with more than 500 beds in Seoul were surveyed to obtain data for study variables. The work environment index was measured by five objective measurements including noise (dB), light(Lux), temperature ($^{\circ}C$), humidity (％) and ventilation (mι/sec). Statistical methods used in this study were descriptive analysis and Pearson product moment correlation analysis. The number of beds, space of foodservice system, the proportion of dishwashing area space in foodservice system area, noise, humidity, and ventilation were significantly correlated to the work environment of the dishwashing area.

• 한국실내디자인학회논문집
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• 제13호
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• pp.32-36
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• 1997

This study is on the interior design standards which is based on the user participicatiov. The design standards in office planning is relied on user participication with practical method and suitable survey item. On space programming and zonning phase, work relationship, visiting rate and characteristics of work can be applied. The rate to take desk-occupancy, information processing grade, the needs of side work table, visitor table and surplus storage space can help to get workstation unit type. The layout of units can be applied on the grade of communication and work-concetration.

• International Journal of Computer Science & Network Security
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• 제22권11호
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• pp.272-278
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• 2022

The article proves the idea that the protection and development of Ukraine as an independent, sovereign state requires the education of a patriot citizen who is able to live and work in a democracy, ensure the unity of Ukraine, feel constant responsibility for himself, his people, the country, and strive to make a real contribution to reform processes, especially in unstable, wartime. The main goal of educational institutions in the system of educational work of the modern information space is revealed. The tasks of patriotic education of the individual are presented. The content of patriotic education at the wartime stage and the main characteristics of the content of patriotism are substantiated. The main methodological positions that are taken into account in the construction of the structure and dynamics of the formation of civil responsibility of the individual are highlighted. The structure of civic responsibility as an integral system of the modern information space is drawn, which includes three subsystems that characterize the natural, social and systemic qualities of citizenship, interconnected hierarchically and synergistically. The components of the structural part of the model of civil culture of the individual in the modern information space are analyzed.Modern modernization of the education system in the modern information space, which has led to the emergence of a new type of Educational Institutions, requires the search for new pedagogical technologies that can ensure the formation of a patriotic citizen with an active civic position, which involves not only mastering students' knowledge about the rights and obligations of citizens, convincing them of the expediency of democratic transformations of society, the formation of high moral and strong-willed, patriotic qualities and feelings, but also identifying motivated civic actions, actions that are necessary during martial law in Ukraine.

• 한국실내디자인학회논문집
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• 제10호
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• pp.3-10
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• 1997

The purpose of this study was to identify and categorize the space use characteristics of the university professor's office. The data were recorded and collected through the physical trace method. Acture Measurement. Photograph, sketch and CAD drawings were used to trace 118 professors offices at Yonse-University. The analysed features were the user characteristics, the size, characteristics of space (such as composition, layout and furniture arrangement), the appliance and the instrument characteristics. To categorize the 'space use' characteristics. 6 variables were used: 1) the territorial characteristics, 2) the spatial relationship between professor's territory and entrance, 3) the layout type of work area, 4) the spatial relationship between professor's and assistant's work area, 5) the arrangement of table, and 6) the completion of sofa set. The results of this study are expected to be used as a basis for the development of design alternatives for the most typical university professors' office.