• Journal of Gastric Cancer
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• 제17권2호
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• pp.145-153
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• 2017

Purpose: Identification of the infrapyloric artery (IPA) type is a key component of pylorus-preserving gastrectomy. As the indocyanine green (ICG) fluorescence technique is known to help visualize blood vessels and flow during reconstruction, we speculated that this emerging technique would be helpful in identifying the IPA type. Materials and Methods: From August 2015 to February 2016, 20 patients who underwent robotic or laparoscopic gastrectomy were prospectively enrolled. After intravenous injection of approximately 3 mL of ICG (2.5 mg/mL), a near-infrared fluorescence apparatus was applied. The identified shape of the IPA was confirmed by examining the actual anatomy following infrapyloric dissection. Results: The mean interval time between ICG injection and visualization of the artery was 22.2 seconds (range, 14-30 seconds), and the mean duration of the arterial phase was 16.1 seconds (range, 9-30 seconds). The overall positive predictive value (PPV) of ICG fluorescence in identifying the IPA type was 80% (16/20). The IPA type was incorrectly predicted in four patients, all of whom were obese with a body mass index (BMI) of more than $25kg/m^2$. Conclusions: Our preliminary results indicate that intraoperative vascular imaging using the ICG fluorescence technique may be helpful for robotic or laparoscopic pylorus-preserving gastrectomy.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제17권1호
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• pp.7-14
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• 2011

This paper is intended to suggest some reference materials for future specialization of university education about healthcare facility design in Korea, by reviewing the degree systems and curriculum of 5 universities where architecture departments have specialized program for healthcare facility design in USA. Research method includes the navigation of related homepages, the e-mail contacts with the professors in charge, and the analysis of collected materials. Some conclusions can be summarized as following : Degrees of the specialized programs under concentration or track system are awarded as the same title as master program in the department of Architecture. Specialized education programs can be largely classified by concentration/track systems( Clemson University, University of Kansas and Arizona State University) which are operated independently in general and certificate system(Texas A&M University and Texas Tech University) which adds some healthcare related courses to general master program in the department of Architecture. As distinctive curriculum from 5 Universities, Clemson University which offers almost courses related to healthcare facility design, University of Kansas which provides internships(6 credits each) for summer term & fall semester of 2nd year, and Texas Tech University where certificate program is co-operated by architecture and nursing department can be mentioned. In order to pursuit the specialization of university education about healthcare facility design in the department of Architecture, it would be desirable to proceed it after setting the direction such as concentration, track or certificate system according to the various circumstances & conditions of the department concerned.

• 한국컴퓨터정보학회논문지
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• 제10권3호
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• pp.173-182
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• 2005

본 논문에서는 항해 시 위치인식에 사용하기 위하여 카메라의 뷰포인트에 무관한 랜드마크를 인식하는 방법을 제안한다. 기존연구에서 사용된 특징들은 카메라의 뷰포인트에 따라 변하고 이에따른 정보 양의 증가로 위치확인을 위한 시각적인 랜드마크의 추출이 어렵다. 본 논문에서 제안된 방법은 특징 추출단계, 학습과 인식단계, 정합단계의 삼단계로 구성된다. 특징 추출단계에서는 영상의 관심영역을 설정, 이 영역 안에서 코너점을 추출하는데, 추출 시 작은 고유값의 통계적 분석을 통해 보다 정확하고 잡음에 강한 특징을 추출하는 방법을 제안한다. 학습 및 인식단계에서는 5개의 특징점으로 구성된 특징모델이 뷰포인트에 무관한 특징점인지를 검사하여 강건 특징모델을 구성한다. 정합단계에서는 시간 복잡도를 줄이고 정확한 대응점을 산출하기 위하여 유사도 평가함수와 Graham 탐색방법을 이용한 정합 방법을 제안한다. 실험에서는 다양한 실내영상을 가지고 제안한 방법과 기존방법을 비교 분석함으로써 제안한 방법의 우수함을 보였다.

• 한국항만학회지
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• 제14권2호
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• pp.175-185
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• 2000

Today freeway is experiencing a severe congestion with incoming or outgoing traffic through freeway ramps during the peak periods. Thus, the purpose of this study is to identify the traffic characteristics, analyze the relationships between the traffic characteristics and finally construct the delay predictive models on the rap junctions of freeway with 70mph speed limit. From the traffic analyses, and model construction and verification for delay prediction on the ramp junctions of freeway, the following results were obtained : ⅰ) Traffic flow showed a big difference depending on the time periods. Especially, more traffic flows were concentrated on the freeway junctions in the morning peak period. ⅱ) The occupancy also showed a big difference depending on the time periods, and the downstream occupancy(Od) was especially shown to have a higher explanatory power for the delay predictive model construction on the ramp junctions of freeway. ⅲ) The delay-occupancy curve showed a remarkable shift based on the occupancies observed : O$\_$d/〈9% and O$\_$d/$\geq$9%. Especially, volume and occupancy were shown to be highly explanatory for delay prediction on the ramp junctions of freeway under O$\_$d/$\geq$9%, but lowly for delay prediction on the ramp junctions of freeway under O$\_$d/〈9%. Rather, the driver characteristics or transportation conditions around the freeway were thought to be a little higher explanatory for the delay prediction under O$\_$d/〈9%. ⅳ) Integrated delay predictive models showed a higher explanatory power in the morning peak period, but a lower explanatory power in the non-peak periods.

• 한국농공학회지
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• 제13권4호
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• pp.2471-2478
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• 1971

Go Cong Water Control Project was conducted on its preliminary survey and design by Agricultural development Corporation for the Korean Government, an Executing Agency, and Directorate of Irrigation and Rural Engineering of the Ministry of Land Reform, Agriculture and Fishery Development for the Vietnamese Government, a cooperation Agency, under Korean and Vietnamese Economic and Technical Cooperation Program. The main purposes of the project are aimed at the improvements of irrigation and drainage, and salt water prevention of the Go Cong area located at northern part of the Mekong Delta. All the works from field survey through design to preparing reports were carried out by ADC alone and recently Korean Government submitted the relevant reports to vietnamese Government through official channel. The contents of the project are summarized as following: 1. The project comprises irrigation, drainage and salt water prevention facilities on the benefited area of about 55,000 hectares, covering Go Cong and Dinh Tuong(My Tho) Provinces and it will be possible to cultivate rice cropping twice a year, irrigating all the area in the dry season; 2. With completion of this project, annual production of rough rice and vegetables are anticipated to increase by 222,600 .T. and 142,600 M.T. respectively and the internal rateof return stants at 26 per cent, applying for the exchange rate of US $ 1 to VN $ 275. 3. Total investments required for the project are estimated at US $ 56,394,000 of which actual construction cost is estimated at US $ 39,183,000. The project has planned to be d to be developed by four stages, taking bout 7 years. 4. The project needs for three places of pumping plants. 57Km of feed and main irrigation canals, 81Km of drainage channels, 97Km of dike, 23 places of sluices and navigation locks, etc.

• 정보과학회 논문지
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• 제42권7호
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• pp.889-900
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• 2015

최근 복잡해진 시스템의 실행 환경에서 발생하는 문제들을 해결하기 위해 자가적응형 시스템의 중요성이 대두되고 있다. 그러나 시스템 설계 시점에 구축된 모델과 실행 환경 사이의 불확실성이 시스템을 알 수 없는 상황으로 이끌 수 있기 때문에 이를 다루기 위한 연구가 중요한 이슈로 떠오르고 있다. 본 논문은 불확실한 상황에서 적응 시점을 결정하고 모델에 실시간 환경을 반영하기 위한 방법을 제안한다. 적합한 적응 시점을 위해 시스템의 이전 상태들과 현재상태를 비교하여 베이지안 서프라이즈를 계산하고, 설계된 모델에 실시간 환경을 수행된 적응 정책의 결과를 모델에 반영한다. 제안 방법론을 네비게이션 시스템에 적용하여 제안 사항의 유효성을 확인하였다.

• 해양환경안전학회지
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• 제28권5호
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• pp.791-799
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• 2022

유선 및 도선 중 선박길이 12미터 미만인 소형선박은 선박안전법에 따른 복원성 기준 적용이 면제되며, 유선 및 도선 사업법에 따라 승객 및 선원이 탑승 가능한 면적을 고려하여 승선정원을 정하고 있다. 이러한 유선 및 도선 중에서는 건조 이후 차양의 설치 등 복원성에 영향을 미치는 상부 구조물을 설치하는 사례도 적지 않다. 이에 본 연구에서는 상부 구조물을 설치한 도선에서 실제 발생한 전복사고의 사례를 바탕으로 해당 도선의 복원성을 추정하여 사고 원인을 분석하고자 하였다. 분석 결과, 승선정원을 초과한 상태에서 승객들이 동시에 하선하고자 기립하여 복원성이 악화된 것으로 나타났으나, 해당 도선이 승선정원을 준수하더라도 한쪽 현의 승객들이 기립하면 횡경사에 의한 전복의 가능성이 존재하였다. 따라서, 보다 안전한 유선 및 도선사업을 위하여 선박길이 12미터 미만의 유선 및 도선에 대하여 건조 및 개조 시 실선 복원성 시험에 의한 승선정원 산출, 승선정원의 총중량 한곗값 제시 등을 개선방안으로 제시하였다.

• 대한조선학회논문집
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• 제61권3호
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• pp.170-184
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• 2024

With the advancement of autonomous navigation technology in maritime domain, there is an active research on swarming Unmanned Surface Vehicles (USVs) that can fulfill missions with low cost and high efficiency. In this study, we propose a formation control algorithm that maintains a certain shape when multiple unmanned surface vehicles operate in a swarm. In the case of swarming, individual USVs need to be able to accurately follow the target state and avoid collisions with obstacles or other vessels in the swarm. In order to generate guidance commands for swarm formation control, the potential field method has been a major focus of swarm control research, but the method using the potential field only uses the position information of obstacles or other ships, so it cannot effectively respond to moving targets and obstacles. In situations such as the formation change of a swarm of ships, the formation control is performed in a dense environment, so the position and velocity information of the target and nearby obstacles must be considered to effectively change the formation. In order to overcome these limitations, this paper applies a method that considers relative velocity to the potential field-based guidance law to improve target following and collision avoidance performance. Considering the relative velocity of the moving target, the potential field for nearby obstacles is newly defined by utilizing the concept of Velocity Obstacle (VO), and the effectiveness and efficiency of the proposed method is verified through swarm control simulation, and swarm control experiments using a small scaled unmanned surface vehicle platform.

• 해양환경안전학회지
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• 제27권6호
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• pp.875-882
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• 2021

통상적으로 직업소음에 의한 청력손실을 최소화하기 위해서는 작업자가 8시간 동안 85 dBA 이상 소음에 노출되지 않도록 권고하고 있다. 이번 연구에서는 실습선박에서 7종류의 담당업무별 작업자들의 소음노출레벨을 측정하였다. 항해 중, 24시간 동안 작업자의 위치하는 A특성등가소음레벨(L_Aeq,i)과 소음장소의 지속기간(h) 및 소음기여도(L_ex,24h,i)를 고려한 소음노출레벨(L_ex,24h)을 측정하였다. 그 결과, 갑판사관 그룹 L_ex,24h=56.1 dB, 갑판부원 그룹은 L_ex,24h=58.9 dB, 실습항해사들은 L_ex,24h=62.0 dB, 취사부원들은 L_ex,24h=64.3 dB, 실습기관사그룹은 L_ex,24h=91.1 dB, 기관사관 그룹은 L_ex,24h=91.1 dB, 그리고 기관부원 그룹은 L_ex,24h=95.1 dB를 나타내고 있다. 따라서 기관 업무를 담당하는 기관사들, 기관부원들 그리고 기관실습생들은 반드시 청력보호구를 착용해야함을 알 수 있었다. 소음이 심한 기관실에서 청력보호구를 착용한다면 기관사관그룹은 L_ex,24h=23.1 dB, 기관부원그룹은 L_ex,24h=24.4 dB 그리고 기관실습생들은 L_ex,24h=21.5 dB의 소음노출레벨을 줄일 수 있을 것으로 추정된다. 또한 실습생들의 거주구역인 제2 강의실 겸 식당구역에 바닥시공을 64 mm, A-60-class 뜬바닥 구조로 개선했다면 실습항해사들의 소음노출도는 L_ex,24h=4.3 dB, 실습기관사들은 L_ex,24h=1.8 dB 정도 추가적인 감소가 있었을 것이다.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 1993년도 Fifth International Fuzzy Systems Association World Congress 93
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• pp.975-976
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• 1993

This talk presents the overview of the author's research and development activities on fuzzy inference hardware. We involved it with two distinct approaches. The first approach is to use application specific integrated circuits (ASIC) technology. The fuzzy inference method is directly implemented in silicon. The second approach, which is in its preliminary stage, is to use more conventional microprocessor architecture. Here, we use a quantitative technique used by designer of reduced instruction set computer (RISC) to modify an architecture of a microprocessor. In the ASIC approach, we implemented the most widely used fuzzy inference mechanism directly on silicon. The mechanism is beaded on a max-min compositional rule of inference, and Mandami's method of fuzzy implication. The two VLSI fuzzy inference chips are designed, fabricated, and fully tested. Both used a full-custom CMOS technology. The second and more claborate chip was designed at the University of North Carolina(U C) in cooperation with MCNC. Both VLSI chips had muliple datapaths for rule digital fuzzy inference chips had multiple datapaths for rule evaluation, and they executed multiple fuzzy if-then rules in parallel. The AT & T chip is the first digital fuzzy inference chip in the world. It ran with a 20 MHz clock cycle and achieved an approximately 80.000 Fuzzy Logical inferences Per Second (FLIPS). It stored and executed 16 fuzzy if-then rules. Since it was designed as a proof of concept prototype chip, it had minimal amount of peripheral logic for system integration. UNC/MCNC chip consists of 688,131 transistors of which 476,160 are used for RAM memory. It ran with a 10 MHz clock cycle. The chip has a 3-staged pipeline and initiates a computation of new inference every 64 cycle. This chip achieved an approximately 160,000 FLIPS. The new architecture have the following important improvements from the AT & T chip: Programmable rule set memory (RAM). On-chip fuzzification operation by a table lookup method. On-chip defuzzification operation by a centroid method. Reconfigurable architecture for processing two rule formats. RAM/datapath redundancy for higher yield It can store and execute 51 if-then rule of the following format: IF A and B and C and D Then Do E, and Then Do F. With this format, the chip takes four inputs and produces two outputs. By software reconfiguration, it can store and execute 102 if-then rules of the following simpler format using the same datapath: IF A and B Then Do E. With this format the chip takes two inputs and produces one outputs. We have built two VME-bus board systems based on this chip for Oak Ridge National Laboratory (ORNL). The board is now installed in a robot at ORNL. Researchers uses this board for experiment in autonomous robot navigation. The Fuzzy Logic system board places the Fuzzy chip into a VMEbus environment. High level C language functions hide the operational details of the board from the applications programme . The programmer treats rule memories and fuzzification function memories as local structures passed as parameters to the C functions. ASIC fuzzy inference hardware is extremely fast, but they are limited in generality. Many aspects of the design are limited or fixed. We have proposed to designing a are limited or fixed. We have proposed to designing a fuzzy information processor as an application specific processor using a quantitative approach. The quantitative approach was developed by RISC designers. In effect, we are interested in evaluating the effectiveness of a specialized RISC processor for fuzzy information processing. As the first step, we measured the possible speed-up of a fuzzy inference program based on if-then rules by an introduction of specialized instructions, i.e., min and max instructions. The minimum and maximum operations are heavily used in fuzzy logic applications as fuzzy intersection and union. We performed measurements using a MIPS R3000 as a base micropro essor. The initial result is encouraging. We can achieve as high as a 2.5 increase in inference speed if the R3000 had min and max instructions. Also, they are useful for speeding up other fuzzy operations such as bounded product and bounded sum. The embedded processor's main task is to control some device or process. It usually runs a single or a embedded processer to create an embedded processor for fuzzy control is very effective. Table I shows the measured speed of the inference by a MIPS R3000 microprocessor, a fictitious MIPS R3000 microprocessor with min and max instructions, and a UNC/MCNC ASIC fuzzy inference chip. The software that used on microprocessors is a simulator of the ASIC chip. The first row is the computation time in seconds of 6000 inferences using 51 rules where each fuzzy set is represented by an array of 64 elements. The second row is the time required to perform a single inference. The last row is the fuzzy logical inferences per second (FLIPS) measured for ach device. There is a large gap in run time between the ASIC and software approaches even if we resort to a specialized fuzzy microprocessor. As for design time and cost, these two approaches represent two extremes. An ASIC approach is extremely expensive. It is, therefore, an important research topic to design a specialized computing architecture for fuzzy applications that falls between these two extremes both in run time and design time/cost. TABLEI INFERENCE TIME BY 51 RULES {{{{Time }}{{MIPS R3000 }}{{ASIC }}{{Regular }}{{With min/mix }}{{6000 inference 1 inference FLIPS }}{{125s 20.8ms 48 }}{{49s 8.2ms 122 }}{{0.0038s 6.4㎲ 156,250 }} }}