• 한국정보전자통신기술학회논문지
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• 제16권5호
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• pp.223-229
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• 2023

본 논문에서는 벡터제어 기법을 적용하는 교류 전동기 PI(비례-적분) 전류제어를 위한 주요 시스템 파라미터를 측정하는 방법을 제시한다. 전류제어를 위해서 PI 제어입력은 여러 선택적 방법에 의해 튜닝될 수 있다. 그 여러 방법들 중에서 주요 계통 파라미터인 권선 저항과 인덕턴스를 이용하는 방법이 빈번히 사용된다. 본 연구에서는 단순 궤환 제어의 결과들을 통해서 이 두 파라미터를 분석, 계측하는 기법을 제시한다. 이 분석적 측정 방법은 단위 계단 또는 다중 계단 기준 명령에 대해 단순 비례 궤환 이득을 이용하는 P 제어의 출력들을 분석하여 단계적으로 파라미터들을 계측해 내는 방법이다. 이 기법은 실시간적인 해석적 계측 방법으로 추가 계측 회로들 및 복잡한 계측 알고리즘들을 사용하지 않고 교류전동기의 벡터제어를 위한 토크성분과 자속성분 전류 제어이득을 같이 연산할 수 있는 방법이다.

• Journal of Electrochemical Science and Technology
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• 제15권1호
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• pp.96-110
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• 2024

Polymer electrolyte membrane fuel cells (PEMFCs) are green energy conversion devices, for which commercial markets have been established, owing to their application in fuel cell vehicles (FCVs). Development of cathode electrocatalysts, replacing commercial Pt/C, plays a crucial role in factors such as cost reduction, high performance, and durability in FCVs. PtNi octahedral catalysts are promising for oxygen reduction reactions owing to their significantly higher mass activity (10-15 times) than that of Pt/C; however, their application in membrane electrode assemblies (MEAs) is challenged by their low stability. To overcome this durability issue, various approaches, such as third-metal doping, composition control, halide treatment, formation of a Pt layer, annealing treatment, and size control, have been explored and have shown promising improvements in stability in rotating disk electrode (RDE) testing. In this review, we aimed to compare the features of each strategy in terms of enhancing stability by introducing a stability improvement factor for a direct and reasonable comparison. The limitations of each strategy for enhancing stability of PtNi octahedral are also described. This review can serve as a valuable guide for the development of strategies to enhance the durability of octahedral PtNi.

• 융합보안논문지
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• 제23권4호
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• pp.122-129
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• 2023

제4차 산업혁명 기술의 혁신적 발전에 따라 전쟁의 패러다임이 변화하고 있다. 특히, 미군의 군사혁신 측면에서 제안된 모자이크전은 다양한 무기, 플랫폼, 정보시스템, 인공지능 등 다양한 자원과 능력을 조합하여 유동적인 작전 수행과 상황에 대응하는 능력을 강화하는 것을 목표로 한다. 이러한 개념의 도입은 AI 참모와 인간 지휘자의 결합으로 효과적이고 신속한 지휘통제를 촉진할 수 있다. 모자이크전은 이미 러시아의 침공에 대응하기 위해 우크라이나군의 작전에 도입된 바 있다. 본 논문은 미래전의 모델로 제안되고 있는 모자이크전 개념을 중심으로 전장 패러다임 변화에 따른 한국형 모자이크전 개념 도입을 위한 조건을 도출하고 전략을 제시한다.

• 한국조리학회지
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• 제6권1호
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• pp.57-78
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• 2000

In the 21st century the size of sales of food service business in Korea will be 30 trillion won which means Food service business in Koreas is a mega market, but it is only quantitative growth and might face the limit of growth. At the same time it is predicted that from the academic world Food service business will develop endlessly after IMF condition. Of course I hope so as a member of national. Al though I propose that quantitative side is important, qualitative side must not be disregarded the present and future customer is needs should be met because the 1st goal of company is to achieve a management goal and pursuit profit. The present situation requires a peculiar and specific strategy of its own which can not be followed by competing hotels so that value can be created and buying intention can be occurred after buying. Until now the goal of marketing campaign has been transacted marketing just for closing a transaction, but it must be related marketing which is seeking mutual interests of customer and company. The strategies to attain these goals are : 1) to change from products and service management-focused to customer management and relationship building-focused. 2) to establish a core strategy which needs to be changed from market occupancy of volume expansion to customer occupancy. 3) to change from one-way communication to two-way communication. 4) to change from large scale marketing by company dimension to small scale marketing by sections. If companies focus on core benefit and augmented service to be sought by customers and make every efforts to create a value customer occupancy will increase automatically, the reduction of marketing cost will be followed, and marketing efforts will be much more efficient. In introducing a new product it is still easier to diffuse through the existing customers, and also important market information can be obtained from customers using this close relationship. If this close relationship maintains well customers will say even a trivial inconvenience and complaint and propose an idea of new product. Kotler divides relationship marketing into 5 stages such as Basic, Reactive, Accountable, Proactive, and Partnership. From the 1st stage to the last stage customer management is absolutely important and also in management strategy. The last stage, Partnership can come into the stage which is actively participated in service development and problem solving by customers. so more loyal customers have more successful performance the company attain.

• ETRI Journal
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• 제35권5호
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• pp.849-858
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• 2013

In this paper, we propose a new adaptive single model to track a maneuvering target with abrupt accelerations. We utilize the stochastic differential equation to model acceleration of a maneuvering target with stochastic volatility (SV). We assume the generalized autoregressive conditional heteroscedasticity (GARCH) process as the model for the tracking procedure of the SV. In the proposed scheme, to track a high maneuvering target, we modify the Kalman filtering by introducing a new GARCH model for estimating SV. The proposed tracking algorithm operates in both the non-maneuvering and maneuvering modes, and, unlike the traditional decision-based model, the maneuver detection procedure is eliminated. Furthermore, we stress that the improved performance using the GARCH acceleration model is due to properties inherent in GARCH modeling itself that comply with maneuvering target trajectory. Moreover, the computational complexity of this model is more efficient than that of traditional methods. Finally, the effectiveness and capabilities of our proposed strategy are demonstrated and validated through Monte Carlo simulation studies.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2045-2050
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• 2003

This paper describes the development of service robotic systems with the Tripodal schematic control architecture. We show practical advantages of the proposed architecture by giving examples of our experience. First, we explain how to add new task using Tripodal architecture approach. The Tripodal architecture provides some crucial organizing principles and core components that are used to build the basis for the system. Thus, the newly developed behaviors, motion algorithm, knowledge, and planning schemes are arranged so as to guarantee the efficiency of the performance of components. Second, we describe the reusability and scaleability of our architecture by introducing the implementation process of the guide robot Jinny. Most of modules developed for former robots like PSR-1 and PSR-2 systems are used directly to the Jinny system without significant modification. Experimental results clearly showed that the developed strategy is useful, even if the hardware configurations as well as software algorithms are more complex and more accumulating.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제48권7호
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• pp.369-375
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• 1999

This paper presents the novel low-performance single-phase voltage regulator which has common arm between the AC/DC and DC/AC power converters and adopts appropriate switching strategy, resulting in the reduction of the number of switching devices. Moreover, by introducing the method to replace the method to replace the conventional AC condenser in filter circuit with the new low-cost type using two DC condenser, the whole voltage regulator system can be more compact, simpler and less expensive than conventional ones. The fully digital controller is designed using high speed DSP, and the proposed system is validated through the experimental results.

• 한국컴퓨터산업학회논문지
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• 제8권1호
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• pp.1-8
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• 2007

객체지향기술을 이용하여 소프트웨어를 개발할 때 소위 @큰 그림@ (big picture)으로 나타내는 @design-first@ approach 방식으로 채택하는 하는 경향이 있어 관심을 끌고 있다. 본 연구도 이 방식을 채택하여 video rental store(VRS) system을 개발하였다 이 system은 효과적으로 모델링(modeling) 할 수 있도록 UML을 이용하였으며, PHP script, MySQL Database, Java를 함께 사용하였으며, 실습 프러적트(project)로 구현하였다. 단계별 프로세싱을 통해 학생들이 프로그래밍을 작성하는데 원칙을 따르도록 지도 하였으며, 코딩(coding)을 시작하기 전에, 계획, 분석, 그리고 설계를 이행하도록 지도했다. 학생들이 가능한 실제 세계와 같은 경험을 가지도록 노력했다. 그리고 전반적으로 그 개발과정은 긍정적이었다.

• 한국주거학회논문집
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• 제21권6호
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• pp.119-129
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• 2010

The purpose of this study was to identify perception on housing welfare of social welfare practitioners. Specific research interest was focused on the area of housing welfare services and necessity, problems when execute housing welfare services, and activating strategy of housing welfare. For the research purpose, questionnaires were distributed to 537 people who work in the field of social welfare including social welfare officials in local government authorities and social workers at community welfare centers nationwide by mail and e-mail and 405 questionnaires were analyzed using SPSS 15.0 program. Respondents thought that the supply of public rental housing was the most important service to promote housing welfare. They also indicated the most serious problem was the lack of budget and housing welfare services and programs. As main reasons of local government's passive attitude toward housing welfare services and programs, respondents mentioned low interest level of housing welfare and lack of housing welfare education. Most of the respondents agreed the necessity of introducing the curricula related to housing welfare and expected to spread interest toward housing welfare in the field of social welfare.

• 한국의상디자인학회지
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• 제20권2호
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• pp.89-100
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• 2018

This study investigated students' perception of a starting up business in the fashion design related departments of two year colleges to present the basic data for designing a start up business education and examined the opening status of the start up business subjects. Only 4.4% of respondents answered that they had an experience in a start up. And 76.2% of respondents answered that they would like to start up a business after graduation. The initial start up types were "online shopping mall" and "blog market" in that order. Nearly 86.7% of respondents answered that they needed "start up" education in college. To the question of whether they would participate if there is a start up extracurricular program, and the subject they would choose, 40.9% answered "I want to get a start up related certification", showing the highest rate of interest in the course. The status of introducing start up business subjects in the regular courses in fashion design related departments in 25 two year colleges related that there were 11 start up related courses begun in the last semester, that is, the 2nd semester of the 2nd year. Since the proportion of clothing in online shopping malls is high, start up education based on the demands of students in fashion design majors can be used as another employment exit strategy.