• 전기학회논문지
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• 제67권8호
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• pp.1089-1098
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• 2018

In this paper, we propose an autonomous feeding robot and its obstacle classification system using ultrasonic sensors to secure the driving safety of the robot and efficient feeding operation. The developed feeding robot is verified by operation experiments in a cattle shed. In the proposed classification algorithm, not only the maximum amplitude of the ultrasonic echo signal but also two gradients of the signal and the variation of amplitude are considered as the feature parameters for object classification. The experimental results show the efficiency of the proposed classification method based on the Support Vector Machine, which is able to classify objects or obstacles such as a human, a cow, a fence and a wall.

• Journal of Welding and Joining
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• 제31권4호
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• pp.17-22
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• 2013

The excellent beam quality of high power fiber lasers are commonly used for remote welding applications in body job applications. The Welding speed and productivity is unmatched with any other welding technology including resistance spot welding or traditional laser welding. High tooling cost for clamping and bulky safety enclosures are obstacles which are limiting the use. With the newly developed Laser stitch welding gun we have an integrated clamping in the process tool and the laser welding is shielded in a way that no external enclosure is needed. Operation of this laser welding gun is comparable with resistance spot welding but 2-times faster. Laser stitch welding is faster than spot welding and slower than remote welding. It is a laser welding tool with all the laser benefits like welding of short flanges, weld ability of Ultra High Strength steel, 3 layers welding and Aluminium welding. Together with low energy consumption and minimum operation cost of IPG fiber laser it is a new and sharp tool for economic car body assembly.

• 전기학회논문지
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• 제64권10호
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• pp.1411-1417
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• 2015

The installation of PV system to the power distribution system is being increased as one of solutions for environmental pollution and energy crisis. However, the efficiency of PV system is getting decreased because of the aging phenomenon and several operation obstacles. Therefore, The technology development of aging diagnosis of PV modules are required in order to improve operation performance of PV modules. This paper proposes evaluation algorithm for aging state in PV modules by using the electrical characteristics of PV modules and environmental factors. And also, this paper presents a operation evaluation system of PV modules based on the proposed aging diagnosis algorithm of PV modules. From the simulation results of proposed evaluation system, it is confirmed that the proposed algorithm is a useful tool for aging diagnosis of PV systems.

• 한국재난정보학회 논문집
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• 제10권2호
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• pp.282-286
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• 2014

본 논문에서는 90개의 시설을 대상으로 물리적 보안시스템 구축 및 운용수준에 대해 조사하여 결과를 분석하고 향상방안을 제시하였다. CCTV에 대한 구축수준과 운영수준이 출입통제시스템이나 침입감지시스템에 비해 높은 것으로 나타났으나 구축된 보안시스템에 대한 개선이나 유지 관리 수준이 낮게 나타나 구축 후 관리가 부족하게 나타났다. X-ray 검색기를 설치한 시설이 적게 나타났지만 이는 물품의 반입 반출을 검색에 대한 관심을 보여주는 것이라 할 수 있다. 물리적 보안시스템을 통합적으로 구축 운영 수준이 비교적 낮게 나왔는데, 물리적 보안시스템의 기능과 보안인력의 기능이 연계될 수 있도록 기술과 운영을 포함한 통합보안운영체계 구축을 확대하는 것이 필요하다. 출입통제시스템의 효과를 높이기 위하여 구역별 개인별로 세분화 된 형태로 출입통제시스템을 운용하고, 많은 인원의 출입을 동시에 통제할 수 있고 일정한 경계구역을 설정할 수 있는 스피드게이트와 RFID의 사용을 확대할 필요가 있다.

• 대한공간정보학회지
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• 제22권3호
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• pp.39-46
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• 2014

현재의 GNSS 측위 방법 중 네트워크(network) RTK(Real-Time Kinematic) 측량은 비교적 저렴하고 쉬운 조작방법 등으로 GNSS 측량의 대중화를 형성하고 있다. 하지만 네트워크 RTK 측량 시 현장 여건 및 기타 조건에 관계없이 모호정수(ambiguity) 고정해를 취득한 데이터에 대하여 대부분 그 결과를 무조건적으로 수용하고 이를 실무에 적용하고 있다. 따라서 본 연구에서는 장애물이 존재하는 지역에서 조건별 네트워크 RTK 측량 데이터의 정확도 변화를 고찰하였다. 연구방법으로 수신점으로부터 장애물과의 거리 및 고도각 변화를 주고 GPS 단독수신에 의한 측량과 GPS+GLONASS 조합에 의한 측량을 실시하고 각 취득 데이터의 위치정확도를 비교 분석하였다. 그 결과 시통이 용이한 지역에서는 GPS 단독측위 방법이 정확도에서 양호한 결과를 보였으며, 장애물에 근접한 지역일수록 GPS+GLONASS 조합에 의한 방법이 안정적인 결과로 나타났다. 본 실험의 결과를 기반으로 측위정확도에 영향을 줄 수 있는 다양한 조건별 연구가 진행된다면 대중화 되고 있는 네트워크 RTK 측위 방법의 정확도 향상을 기대할 수 있을 것이다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1927-1932
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• 2003

In a previous study, the authors have proposed the Cooperative Collision Avoidance (CCA) method which enables mobile robots to cooperatively avoid collisions, by extending the concept of the Velocity Obstacle to multiple robot systems. The method introduced an evaluation function considering an operation objective so that each robot can choose the velocity which optimizes the function. As the evaluation function could be of an arbitrary type, this method is applicable to a wide variety of tasks. However, it complicates the optimization of the function especially in real-time. In addition, construction of the evaluation function requires an operation objective of the other robot which is very hard to obtain without communication. In this paper, the CCA method is improved considering such problems for implementation. To decrease computational costs, the previous method is simplified by introducing two essential assumptions. Then, by treating the desired direction of locomotion for each robot as the operation objective, an operation objective estimator which estimates the desired direction of the other robot is introduced. The only measurement required is the other robot's relative position, since the other information can be obtained through the estimation. Hence, communicational devices that are necessary for most other cooperative methods are not required. Moreover, mobile robots employing the method can avoid collisions with uncooperative robots or moving obstacles as well as with cooperative robots. Consequently, this improved method can be applied to general dynamic environments consisting of various mobile robots.

• 통상정보연구
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• 제18권2호
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• pp.53-82
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• 2016

본 연구는 최근 정체기에 접어들었다고 볼 수 있는 전자무역 연구에 조금이라도 도움이 되기 위해 기획되고 연구되었다. 무엇보다 본 연구의 배경은 외국에서의 전자무역에 관한 선행문헌과 국내에서의 전자무역에 관한 선행문헌이 서로 다르다는 것에서 출발한다. 외국에서의 전자무역 연구 동향은 주로 통관 업무에 국한되어 연구가 진행되는 경우가 많았지만 국내에서의 전자무역 연구 동향은 주로 대금결제와 선하증권의 전자화 등 대금결제의 전자화 및 전자신용장의 구축을 중심으로 이루어져 왔다. 이와 같은 차이점이 실제 전자무역 구축에도 그대로 이어져 외국에서의 전자무역 구축 동향과 국내에서의 전자무역 구축 동향이 서로 다소 다르게 이루어졌다. 미국을 중심으로 한 선진국에서는 통관 및 물류 영역을 중심으로 전자무역이 구축되었고 우리나라에서는 통관 영역의 전자화도 이루어졌지만 신용장을 포함한 결제 영역에서도 전자화도 구축되었다. 이에 본 연구에서는 최근에 논의되고 있는 글로벌 전자무역 동향을 비교적 심도 있게 분석하였으며 한국의 전자무역 추진의 핵심 당사자인 한국무역정보통신과 관세청이 구현한 우리나라 전자무역 현황을 알아보고 검토하였다. 이를 바탕으로 한국 전자무역 추진상의 여러 문제점을 도출하였고 이에 대한 해결방안을 제시하였다. 논의 결과, 우리나라 전자무역 구축은 향후 전자신용장 등 대금결제의 전자화 보다는 통관, 물류 영역의 전자화가 더욱 필요하다고 분석되었다.

• 한국항해항만학회지
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• 제30권9호
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• pp.735-740
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• 2006

Marine officers should have crisis control ability because ship operation needs not only highly specialized information, but also functional capability due to the fact that there always exist dangers at sea, which are different from those at shore. Therefore, marine officers should be trained on the related specialized information under the systematical educational system including shipboard training. Their training is also based on the strong spiritual power and physical strength through the strict training process. In order to have these vocational personalities, dormitory life training and shipboard training courses seem to be essential processes, which are required of maritime education. The introduction of automatic system into the ship as a result of the recent development of technology brings decrease of the full number of crew. Consequently, marine officers are increasingly under heavy burden, and should have more ship operation capabilities than before. Maine officers should have not only specialized information which differs from that at shore, but also vocational adaptability which can reasonably tackle with all the problems which exist on the spot and are obstacles to individual, spiritual, physical, natural, and social demands. So it is required that marine officers should have study many areas to deal with as extra curricula besides their major field of study, which are unique characteristics of the education for them. These vocational adaptabilities are based on the spiritual characteristics, such as self-developmental education, responsibility, meticulous care, attentiveness, voluntary, planning, readiness, spontaneity, accuracy, self-denial, obedience, leadership, and etc.

• 한국동물위생학회지
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• 제35권4호
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• pp.321-325
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• 2012

Hazard Analysis Critical Control Point (HACCP) system application is expanded to food chain from farm to table to supply safe livestock products with consumers in Korea. The objectives of this study were to analyze the HACCP operating conditions in butcher shops and to suggest for better HACCP implementation. We analyzed the HACCP inspection reports for butcher shops implemented by the Korea Livestock Products HACCP Accreditation Service from 2007 to 2009 and from 2010 to 2012 to compare the rate of HACCP non-compliances. The overall rate of non-compliances was higher in 2010~2012 than 2007~2009. The current inadequate HACCP operating level was directly related with the business size. Ninety-nine percent of the butcher shops were very small business with under 10 employees in Korea, and these small-sized businesses usually had great difficulties in implementing HACCP due to lack of technical expertise and financial resources. To overcome the obstacles and to facilitate more effective HACCP application and operation in butcher shops, government should play a leading role in developing flexible and simplified HACCP-based system which merges both the pre-requisite and HACCP principles.

• 정보저장시스템학회:학술대회논문집
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• 정보저장시스템학회 2005년도 추계학술대회 논문집
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• pp.185-189
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• 2005

We reported here nano-scale electrical phase-change recording in amorphous $Ge_2Sb_2Te_5$ media using an atomic force microscope (AFM) having conducting probes. In recording process, a pulse voltage is applied to the conductive probe that touches the media surface to change locally the electrical resistivity of a film. However, in contact operation, tip/media wear and contamination could major obstacles, which degraded SNR, reproducibility, and lifetime. In order to overcome tip/media wear and contamination in contact mode operation, we adopted the W incorporated diamond-like carbon (W-DLC) films as a protective layer. Optimized mutilayer media were prepared by a hybrid deposition system of PECVD and RF magnetron sputtering. When suitable electrical pulses were applied to media through the conducting probe, it was observed that data bits as small as 25 nm in diameter have been written and read with good reproducibility, which corresponds to a data density of $1 Tbit/inch^2$. We concluded that stable electrical phase-change recording was possible mainly due to W-DLC layer, which played a role not only capping layer but also resistive layer.