• Journal of Biosystems Engineering
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• 제18권4호
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• pp.305-316
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• 1993

Fuel efficiency in tractor operations dep6nds on the selection of transmission gears and upon the engine being operated at or near maximum torque much of time. The objective of this study was to develop automatic control systems for tractor transmission ratio and governor setting so that the engine is operated at or near maximum torque as much of time as possible. An indoor test unit, which can be used to simulate tractor operation, was built in order to investigate the system design parameters and test the performance of the control system designed. The test-unit consists of engine, gear-type transmission, dynamometer, and control systems for transmission ratio and engine speed. Governor setting lever was controlled by a step motor, and the clutch and transmission levers were controlled by hydraulic cylinders and solenoid valves. The control systems showed good time responses which are assumed to be suitable for optimal tractor operation. The time required for shifting gears from clutch disengagement to engagement was about 1 second, which is almost the same as that for manual shift. And the settling time for engine speed control system was about 5 to 6 seconds.

• 한국공작기계학회논문집
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• 제11권6호
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• pp.38-44
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• 2002

Today most companies are designing their automobile shapes by using 3 dimensional CAD software, CATIA. And they used to design 2 dimensional press dies to do some elastic work on their products, but they are currently trying to make use of 3 dimensional software, Pro-Engineer. In this case, they have to change the 3 dimensional product design data to the proper format data for the following process. This paper will show the data loss and the deformation during data transfer between CATIA and Pro-Engineer, and then suggest a solution for these problems. Product's surface will be automatically placed by automatic press tipping angle setting in CATIA to prevent the product from being stuck m the press die. The 2 dimensional section view which is based on the tipping angle setting is created by Z-map. And, to remove the data loss and the data deformation in Pro-Engineer, the product surface are delivered to the next process after it is changed to the 2 dimensional Z-map curves in CATIA. Finally, this paper suggests an algorithm to develop the automatic design program for the press layout which regenerates product shape surface from the previous process.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2004년도 춘계종합학술대회
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• pp.599-602
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• 2004

본 논문에서는 로봇축구의 식별을 위한 초기 패치(patch)값 및 조명의 변화량에 따른 제어변수의 자동설정 방법을 연구하였다. 먼저 패치값 자동설정을 위해 찾고자하는 국부적인 패치영역을 획득하여 RCB값으로 표본화하고, 기울기 연산자를 적용하여 화소의 기울기 값을 얻는다. 그리고 기울기 값으로부터 유효 패치영역과 YUV값을 구한다. 또한 YUV 성분 중 휘도성분을 측정하여 조명의 변화량에 따른 제어변수를 설정한다. 제안된 방법을 로봇축구 영상에 적용하여 초기 패치값을 설정하였고 경기 중 조명의 변화에 적응적인 패치값 검출이 가능함을 보였다.

• 한국컴퓨터정보학회논문지
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• 제14권3호
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• pp.161-171
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• 2009

본 논문에서는 SOA(Service-Oriented Architecture)를 기반으로 서비스간에 상호 작용하는 데이터의 품질 관리를 위한 오류 정제 서비스를 대상으로 데이터 제약조건 설정 시 인간 개입을 최소화하기 위한 기법을 제안한다. 단, 실세계에서 통용되는 일반적인 데이터를 모두 다루는 것은 불가능하므로 비즈니스 도메인에서 자주 사용되는 CRM(Customer Relationship Management)과 ERP(Enterprise Resource Planning) 서비스와 같이 고객 주문 정보 및 처리에 관련된 데이터를 대상으로 한다. 이를 위해, 컴포지션 되는 서비스간의 상호 작용하는 데이터를 의미적으로 확장하여 확장-엘리먼트 벡터를 생성하고 이를 기반으로 의사결정 트리(decision tree) 학습 방법을 적용하여 제약조건 설정을 자동화하기 위한 규칙 기반 시스템을 구축한다. 이 시스템을 오류정제 서비스에 삽입한 결과, 비즈니스 분야의 공개된 서비스로부터 데이터 학습을 통해 제약조건 설정을 41% 넘게 자동화 할 수 있음을 보였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.510-512
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• 2005

This paper introduces the development of automatic system for estimation of digital relay performance. We have developed an automatic estimation system "HRV2004(Himap Relay function Verifier 2004)" for digital relay in 2004 and it has been verified in the field for one years. This paper describes the development details and field experience of HRV2004. HRV2004 can perform a series of jobs required for the relay testing in one environment and could handle most of all models of protective relay currently produced by Hyundai Heavy Industries. The functionality of this program consists of GUI of relay setting for beginner, fault record analysis and relay performance estimation. The core of this system is an automatic reporting of estimation test. If user is only click a button for relay estimation and one will received testing report to deliver customer. Additional benefit is fast response than the manual estimation. For example, the manual estimation takes spending 6 hours but this system is about 15 minutes.

• Journal of Biosystems Engineering
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• 제19권4호
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• pp.291-300
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• 1994

It is desired to operate tractor engines at or near maximum torque much of the time in field operation to increase fuel efficiency. To do this it is necessary to reduce engine speed and to shift gears to higher ratios as frequently as possible. Because of load variations in most drawbar work and inconvenience in gear shift, however, gear-type transmission are usually set in one ratio at unnecessarily high engine speeds, and engine-torque variations are used to compensate for changes in drawbar load. As a result, the most of time the tractor is not operated efficiently in terms of fuel consumption and work output. The objective of this study was to develop an automatic control system which is able to operate a tractor equipped with gear transmission under the optimal condition in terms of fuel efficiency with automatic governor setting and gear shift. An indoor experimental test set which can be used to simulate tractor operation, control engine speed and transmission ratio was developed in the previous paper. In this paper, the performance of the optimal operation system is reported. Through a series of tests, it was found that the automatic control system for optimal operation of tractors with gear transmission had a satisfactory performance.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2002년도 추계종합학술대회
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• pp.762-763
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• 2002

최근에는 컴퓨터를 이용한 자동 제어나 계측기의 활용이 급격히 증가하고 있다. 본 논문에서는 데이터의 수집 및 제어가 쉽고 데이터 분석 및 적용이 용이한 LabVIEW 그래픽 프로그램을 사용하여 계측장비 제어 및 모니터링, 측정 데이터의 분석, 자동제어가 가능한 자동 부화 시스템을 설계하고 시스템의 검증을 위해 Incubator를 제작하였다. 센서를 통해 Incubator 내부 환경을 측정하고 부화를 위해 선택한 개체의 부화환경을 데이터베이스 파일에서 불러와 최적의 환경 조성을 위해 각 장치들을 초기화 및 제어한다. 이를 통해 미세한 부화 환경의 변화가 부화율과 품질에 주었던 단점을 극복할 수 있을 뿐만 아니라 효율적인 시스템 관리로 인한 인력과 비용의 절감도 기대된다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권10호
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• pp.3815-3833
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• 2021

MILP-based automatic search is the most common method in analyzing the security of cryptographic algorithms. However, this method brings many issues such as low efficiency due to the large size of the model, and the difficulty in finding the contradiction of the impossible differential distinguisher. To analyze the security of ESF algorithm, this paper introduces a simplified MILP-based search model of the differential distinguisher by reducing constrains of XOR and S-box operations, and variables by combining cyclic shift with its adjacent operations. Also, a new method to find contradictions of the impossible differential distinguisher is proposed by introducing temporary variables, which can avoid wrong and miss selection of contradictions. Based on a 9-round impossible differential distinguisher, 15-round attack of ESF can be achieved by extending forward and backward 3-round in single-key setting. Compared with existing results, the exact lower bound of differential active S-boxes in single-key setting for 10-round ESF are improved. Also, 2108 9-round impossible differential distinguishers in single-key setting and 14 12-round impossible differential distinguishers in related-key setting are obtained. Especially, the round of the discovered impossible differential distinguisher in related-key setting is the highest, and compared with the previous results, this attack achieves the highest round number in single-key setting.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 A
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• pp.61-63
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• 1993

This parer propose an adaptive methodlogy for setting of the underfrequency relays that is based on the initial rate of change of the frequency at the relay. During severe emergencies which result in insufficient power generation to meet load, an automatic load shedding program throughout the affected area can prevent total collapse. To avoid this kind of insufficient power generation, load shedding relays are often applied throughput the system to provide a means of helping balance the load to the remaining generation. Comparing, it has been found that the use of the proposed method for the amount and the timing of load shed more efficiently than the conventional method.

• Journal of Platform Technology
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• 제11권5호
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• pp.3-15
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• 2023

Requirements traceability link information is the basis for determining whether requirement change requested throughout the software development life cycle should be reflected in the system. Setting up complete requirements traceability links requires considerable effort. However, the commensurate benefits can be obtained in later development or further maintenance phases. For this reason, setting up and managing requirements traceability links in the software development phase are tasks that cause considerable resistance to developers. This study proposes a method for generating requirement traceability links in business applications. The key feature of the proposed method is that the traceability link from the requirements element, which is the basis of the corresponding element to the analysis element, is automatically established at the same time the elements of the analysis model are identified. This can be a way to reduce developer effort while increasing the efficiency of the traceability model. A case study on a Course Registration System demonstrates the feasibility of applying the proposed requirements traceability management method to actual software development.