• 융합보안논문지
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• 제23권1호
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• pp.45-54
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• 2023

최근 사물인터넷의 발전과 함께 UI가 없는 장치도 간편하게 네트워크에 연결할 수 있는 프로토콜에 관한 연구가 꾸준하게 이루어지고 있다. 이를 위해 Wi-Fi Alliance에서는 QR 코드를 사용하여 네트워크에 연결할 수 있는 Wi-Fi Easy Connect를 발표하였다. 하지만, Wi-Fi Easy Connect는 안전성을 위해 많은 연산량을 요구하고 있어 저전력·소형화된 사물인터넷 장치에 적용하기 어렵다는 문제가 있다. 또한, 확장성을 고려한 Wi-Fi Easy Connect는 유선 환경에서도 동작할 수 있도록 설계되었지만, TLS와 같이 보안 환경을 고려하지 않아 중복 암호화 등의 문제가 발생하고 있다. 따라서 본 논문에서는 Wi-Fi Easy Connect 프로토콜을 분석하고, TLS 환경에서도 효율적으로 동작할 수 있는 프로토콜을 제안한다. 제안하는 프로토콜은 기존 보안 요구사항을 만족함과 동시에 연산량이 큰 ECC scalar multiplication 연산이 약 67% 감소하는 것을 확인할 수 있었다.

• Industrial Engineering and Management Systems
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• 제8권2호
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• pp.109-120
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• 2009

As the use of 3DCAD data became widespread in designing products in manufacturing, attempts have been made to shorten lead time and reduce cost of production preparation utilizing 3DCAD data for launching assembly lines. In order to create assembly plans not only efficient but easy for operators to operate ('easy-to-operate'), this study presents approaches, methods, and systems for creating 3DCGAs (3 Dimensional Computer Graphic Animations) which automatically utilize a prototype-free production preparation methodology. Characteristics of this study include that it proposes the methodology for creating assembly operation 3DCGAs automatically, for all the possible assembly operations corresponding each of the possible assembly sequences first. Using the created 3DCGAs, the study next considers assembly methods by evaluating how easy or 'operator friendly' they are in implementing, and devises tools or jigs to be used, and plans efficient assembly line organization. The concept of the methodology was formed by focusing on the value-adding assembly steps at which parts turn into products directly. The study also validates the effectiveness of the presented methodology by employing the methods used in actual production preparation process in businesses, and proves that an efficient assembly line can be organized in a shorter period of time utilizing the developed system and by preparing easy-to-operate and efficient plans in 3DCGAs at the design stage.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.186-189
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• 2007

The organic deposition chamber has been developed using belt source evaporation techniques for the first time. The deposition chamber is consisted of the belt source, organic vapor source, and the mask alignment assembly. The rollers operate for the thin metal belt to continuously move with the automatic tension control. It has been proved for the belt source evaporation easy to operate and the alignment of the substrate/shadow mask becomes so simple to use in AMOLED manufacturing industry.

• 한국태양에너지학회 논문집
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• 제24권2호
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• pp.89-96
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• 2004

PV system is easy to operate and maintain than the other power generating system since it generally contains no moving parts, operates silently and requires very little maintenance. A solar cell generates DC power from sunlight whose power is different at any instance according to condition of irradiation and temperature variables. In order to improve the system utility factor and efficiency of energy conversion, it is desirable to operate the PV system at maximum power point of solar cell under different condition This paper describes the experimental results of the PV system contain solar modules and a DC-DC converter(boost type chopper) using fuzzy controller. The experimental results show that the PV system always operates at maximum power point of solar cells having stabilized output voltage waveform with relatively small ripple component.

• 대한조선학회 특별논문집
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• 대한조선학회 2005년도 특별논문집
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• pp.159-164
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• 2005

In this paper, we study some problems of the scheduling on the fixed area in a shipbuilding. The scheduling, constrainted a working area, is not easy to make a load balance and to operate a change of daily work plan. we proposed a block arrangement algorithm to make the load balance and developed a system used to operate the change of daily work plan.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1992년도 춘계학술대회 논문집
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• pp.297-300
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• 1992

For the most part of machine design, assembly drawing isaffected byits inserted parts. When a part is inserted in assembly, alreadyd stablished parting line is modified for reasonable representation. for example, break or trim fuction between the lines gives more recognizable drqwing. Most of parts is composed of such that point, line, arc, circle and block. If the part is composed of block, it is very difficult to operate because its attribution is unknown before exploding, but, It is very easy to operate except block. In this paper, it is required that basic feature recognition rules are caused by knowledge-based. This system which shows a good modify tool using AutoCAD system and ADS (Autocad Development System).

• 한국가구학회지
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• 제13권1호
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• pp.42-47
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• 2002

The folding chairs are one of the most necessary furniture for satisfying the moderns' wants which is utilized for limited space rationally. These folding chairs are variously used in interior spaces such as offices, dining areas, and resting areas. They are very easy to move around, so that quiet useful in out door areas, too. Moreover, they play an important role in public spaces as supplementary furniture. The folding chairs have one or several axes, and they are classified according to type of axes like below. 1. Method of divide seating board into 2 and fold, 2. Method of folds seating board and lay on bottom of backboard, 3. Method of fold back board and lay on top of seating board, 4. Method of fold into contact with left and right, 5. Method of gathering legs into one and fold. The folding chairs have to be easy to operate, firm and safe, light for moving around easily, designed for able to change units whenever they have damaged. Change of residential spaces according to the trend towards the nuclear family maximized necessity of limited spaces' use. Therefore, this study provides insights for development of new methods' of folding chairs.

• 한국농공학회지
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• 제10권1호
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• pp.1409-1412
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• 1968

Some simple devices to demonstrate important hydraulic principles are required in fluid mechanics or hydraulics classes. Those devices should be easy to make and operate with inexpensive cost. The writer has studied some simple demonstration apparatus of hydraulic principles which were made of cheap materials. An adjustable nozzle is one of them. It can be connected to an axial flow fan so as to use air flow. By operating this apparatus, pressure changes in gradually enlarged or contracted conduits could be observed.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.133-134
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• 2002

The use of low friction wear resistant coatings for machine components is rapidly increasing. These components may operate in any lubrication regime, and less frequently even unlubricated. When run unlubricated it is easy to see the beneficial effect of a low friction coating. However, it has frequently been shown that the coating may also be very beneficial under boundary and mixed lubrication conditions. The present digest briefly presents a few interesting aspects of the use of low friction coatings in lubricated contact illustrated by selected experimental results.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.1392-1395
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• 1996

Nonlinear PID controllers have increasingly used in current industrial practice because it is robust and is easy to operate. Little guideline and tuning method, however, has been recommended for the nonlinear PID controllers while a lot of result is available for the linear PID controllers. Application guideline and tuning formulae are presented for error square type nonlinear controllers, which are most popular currently, are presented.