• 대한수학회보
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• 제53권2호
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• pp.507-518
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• 2016

In this paper, using forms of conjugations, we give some algebraic properties of bicomplex numbers. We research differential operators, elementary functions and the analogous Cauchy-Riemann system in bicomplex number systems. Also, we investigate the definition and properties of regular functions with values in bicomplex settings in Clifford analysis.

• 충청수학회지
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• 제17권1호
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• pp.47-56
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• 2004

The nonlinearity of a Boolean function f on $GF(2)^n$ is the minimum hamming distance between f and all affine functions on $GF(2)^n$ and it measures the ability of a cryptographic system using the functions to resist against being expressed as a set of linear equations. Finding out the exact value of the nonlinearity of given Boolean functions is not an easy problem therefore one wants to estimate the nonlinearity using extra information on given functions, or wants to find a lower bound or an upper bound on the nonlinearity. In this paper we extend the notion of auto-correlations of Boolean functions to vector Boolean functions and obtain upper bounds and a lower bound on the nonlinearity of vector Boolean functions in the context of their auto-correlations. Also we can describe avalanche characteristics of vector Boolean functions by examining the extended notion of auto-correlations.

• Structural Engineering and Mechanics
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• 제52권3호
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• pp.595-601
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• 2014

For analysis of the plates and membranes by numerical or analytical methods, the question of choice of the system of functions satisfying the different boundary conditions remains a major challenge to address. It is to this issue that is dedicated this work based on an approach of choice of combinations of trigonometric functions, which are shape functions of a bended beam with the boundary conditions corresponding to the plate support mode. To do this, the shape functions of beam vibrations for strength analysis of the rectangular plates by Kantorovich-Vlasov's method is considered. Using the properties of quasi-orthogonality of those functions allowed assessing to differential equation for every member of the series. Therefore it's proposed some new forms of integration of the beam functions, in order to simplify the problem.

• 전기학회논문지
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• 제65권5호
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• pp.753-759
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• 2016

Power automation system to operate power distribution systems can be distinguished by distribution SCADA with remote monitoring and control; and distribution automation system with basic functions such as service restoration to the distribution SCADA; and distribution management system which is operated by various applications in order to enhance distribution system operation performance based on the distribution automation system. In the technological change, a technical boundary of information technology (IT) and operation technology (OT) is being blurred by that new concepts such as interoperability. In addtion, IT/OT convergence has been proposed by the improvement of ICT and power system technology. At the viewpoint, advanced distribution management system (ADMS) to have the new concepts and to increase distribution system operation efficiency through global information and functions from the other systems has been proposed. In order to implement the ADMS, IT and OT have to be employed together on the ADMS; and the concept-based IT/OT convergence concept has been presented. Therefore, this paper introduces ADMS and IT/OT convergence and proposes a design of IT/OT convergence based ADMS system design with configurations and functions.

• International Journal of Control, Automation, and Systems
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• 제3권spc2호
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• pp.315-321
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• 2005

Interactions among multiple control functions of a UPFC installed in a power system have been observed in power system simulation and been reported in authors' previous publications [1,2]. This paper presents new analytical results about these observed interactions and concludes that they are due to the control conflict between the series and shunt part of the UPFC, which are connected through the internal common capacitor inside the UPFC. Investigation in the paper reveals, for the first time as far as the authors are aware of, that the linkage pattern of UPFC series and shunt part decides whether the control functions implemented by the UPFC series and shunt part conflict each other or not. This linkage pattern of UPFC series and shunt part can be described by the flow of active power through the UPFC at steady-state operation of the power system. Hence in order to predict the possible interactions among multiple control functions of the UPFC, an interaction indicator is proposed in the paper which is the direction and amount of active power flow through the internal link of the UPFC series and shunt part at steady-state operation of the power system. This proposed interaction indicator can be calculated from power system load flow solution without having to run simulation of the power system with UPFC controllers installed. By using the indicator, the interactions among multiple control functions of the UPFC caused by badly set controller's parameters are excluded. Therefore the indicator only identifies the possible existence of inherent control conflict of the UPFC.

• 대한토목학회논문집
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• 제31권3D호
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• pp.441-450
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• 2011

최근의 건설공사는 대형화되고 있고 복잡한 시설물들을 포함하고 있으며, 공사비와 공기관리를 위해 프로젝트관리시스템(PMIS)을 적용하고 있다. 국토해양부에서도 산하 공공 발주공사의 사업관리를 위해 건설 CALS 시스템을 사용하고 있다. 본 연구에서는 현재 사용중에 있는 건설 CALS 시스템의 세부 기능 분석을 통해 적용 문제점을 도출하여 실무 활용성을 확대할 수 있는 개선 기능을 제시하고 있다. 국토해양부 산하 5개청에서 발주되는 공사는 모두 건설 CALS 시스템을 PMIS 대용으로 사용하고 있으나, 사용 기능은 제한적이고 소수의 실무진에 의해서만 활용되고 있고, 특히 CALS에 사용되는 각종 공사정보가 단편적 수치 정보로 구성되어 관리자의 정보 이해도 및 수준별 활용도가 저하되어 있는 것으로 파악되었다. 본 연구에서는 CALS 시스템의 활용성 확대를 위한 새로운 기능들의 구성방안과 정보시각화를 위해 세부 기능별로 4D 객체 연동 방안을 제시하고 있다.

• 대한임베디드공학회논문지
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• 제7권5호
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• pp.227-239
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• 2012

Recent advances in electronics have enabled various conventional products to incorporate with numerous powerful microcontroller. Generally, an embedded system is a computer system designed for specific control functions within a larger system, often with real-time computing constraints. The growing performance and reliability of hardware components and the possibilities brought by various design method enabled implementing complex functions that improve the comport of the system's occupant as well as their safety. A cyber physical system (CPS) is a system featuring a tight combination of, and coordination between, the system's computational and physical elements. The concept of cyber physical system, including physical elements, cyber elements, and shared networks, has been introduced due to two general reasons: design flexibility and reliability. This paper presents a cyber physical system where system components are connected to a shared network, and control functions are divided into small tasks that are distributed over a number of embedded controllers with limited computing capacity. In order to demonstrate the effectiveness of cyber physical system, an unmanned forklift with autonomous obstacle avoidance ability is implemented and its performance is experimentally evaluated.

• 전기학회논문지P
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• 제55권3호
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• pp.128-132
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• 2006

The previous MCCs(Motor Control Centers) have the demerits of high cost and much manhour for rework because it is impossible for us to standardize the previous MCCs and they have many manual connections. The customers require the products which can operate with the SCADA system by digitalizing the functions of the current MCCs and the systematized products with capability of remote control. To solve these disadvantages and requirements, we developed the Intelligent Motor Control Center. This system has the various functions such as protection, measuring, and communication. Using these functions, we can monitor motor status through communication with the upper system and define the circuit for lowering connection costs according tn starting type and shortening the manufactural period by the graphic editor. The development of this system results in establishment of the competitive structure with domestic area and Perfect automatic monitoring through linkage with the SCADA system.

• 한국시스템다이내믹스연구
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• 제8권1호
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• pp.49-66
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• 2007

Due to criminal aspects spreading nation wide, their intelligence level increasing and becoming digitalized, the citizens' interest in and desire for crime security have increased. Until now, the preceding researches have been focused on finding the specific variables that have direct effects on the demand for police manpower through regression analysis and attempted to predict number of needs. However, there have never been any researches producing the accurate number of demands for crimes and human resources needed for each work load. Therefore, this research have analyzed each police station functions by interviewing the persons in charge and selected the main duty for each functions. From this, by using the method of system dynamics, this research was able to predict the standard number of manpower needed for each police station functions. Also, by making a model for each 235 police stations, the best efficient employment plan for police stations and district agencies have been further discussed based on the computer simulation results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1156_1158
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• 2009

A train control system(TCS) becomes a large scale and complex as other computer based control systems. So, it is necessary to manage rigorously system requirements specification of the train control system at the early phase. This paper describes Use Cases and activity diagrams of the TCS functions requirements of TCS. Basic functions of the train control system suggested refer to IEC62290-1. And the basic functions includes train operation without a driver.