Development of an Amphibious Robot for Visual Inspection of APR1400 NPP IRWST Strainer Assembly

장유현,김종성 한국원자력학회 2014 Nuclear Engineering and Technology Vol.46 No.3

An amphibious inspection robot system (hereafter AIROS) is being developed to visually inspect the in-containmentrefueling storage water tank (hereafter IRWST) strainer in APR1400 instead of a human diver. Four IRWST strainers arelocated in the IRWST, which is filled with boric acid water. Each strainer has 108 sub-assembly strainer fin modules thatshould be inspected with the VT-3 method according to Reg. guide 1.82 and the operation manual. AIROS has 6 thrusters forsubmarine voyage and 4 legs for walking on the top of the strainer. An inverse kinematic algorithm was implemented in therobot controller for exact walking on the top of the IRWST strainer. The IRWST strainer has several top cross braces that areextruded on the top of the strainer, which can be obstacles of walking on the strainer, to maintain the frame of the strainer. Therefore, a robot leg should arrive at the position beside the top cross brace. For this reason, we used an image processingtechnique to find the top cross brace in the sole camera image. The sole camera image is processed to find the existence of thetop cross brace using the cross edge detection algorithm in real time. A 5-DOF robot arm that has multiple camera modules forsimultaneous inspection of both sides can penetrate narrow gaps. For intuitive presentation of inspection results and formanagement of inspection data, inspection images are stored in the control PC with camera angles and positions to synthesizeand merge the images. The synthesized images are then mapped in a 3D CAD model of the IRWST strainer with the locationinformation. An IRWST strainer mock-up was fabricated to teach the robot arm scanning and gaiting. It is important to arriveat the designated position for inserting the robot arm into all of the gaps. Exact position control without anchor under the wateris not easy. Therefore, we designed the multi leg robot for the role of anchoring and positioning. Quadruped robot design ofinstalling sole cameras was a new approach for the exact and stable position control on the IRWST strainer, unlike atraditional robot for underwater facility inspection. The developed robot will be practically used to enhance the efficiency andreliability of the inspection of nuclear power plant components.

2P-577 : Solution-processable dithieno[3,2-b:2′,3′-d]thiophene derivatives for organic thin-film transistors and complementary-like inverters

장유현,서성용 한국공업화학회 2020 한국공업화학회 연구논문 초록집 Vol.2020 No.-

Solution-processable dithieno[3,2-b:2',3'-d]thiophene(DTT) derivatives, 2,6-bis(phenylethynyl)dithieno[3,2-b:2',3'-d]thiophene (BP-Et-DTT) and 2,6-bis(thiophen-2-ylethynyl)dithieno[3,2-b:2',3'-d]thiophene (BT-Et- DTT) were synthesized and characterized as solution-processable organic semiconductors for organic thin-film transistors (OTFTs). The highest hole mobility was 0.32 cm² V-1 s^-1 based on BP-Et-DTT thin films. The thin films exhibited micrometer-sized crystalline fiber structures which were aligned along the shearing direction, resulting in fiber-alignment-induced charge-transport anisotropy. Furthermore, bulk heterojunction (BHJ) ambipolar transistors were fabricated with an optimized blending ratio of BP-Et-DTT and the representative n-channel semiconductor, PDIFCN₂. Complementary-like inverters were fabricated based on the two identical ambipolar transistors, resulting in moderate voltage gains of up to 16.

관광스타트업 창업경험에 대한 현상학적 연구 - 진화경제론적 관점에서 관광 비즈니스 생태계를 중심으로-

장유현 한국관광학회 2018 한국관광학회 국제학술발표대회 Vol.84 No.-

파터 팽대부 선종 및 선암종에서 p37 유전자의 변이

장유현,이우진,류지곤,김용태,윤용범,김선희,김우호 대한췌담도연구회 2000 대한췌담도연구회지 Vol.5 No.1

신고리 3,4호기 IRWST 원격점검용 로봇 개발

장유현 한국소음진동공학회 2013 한국소음진동공학회 강습회 Vol.2013 No.6

수중 로봇을 활용한 발전소 복잡구조물 원격점검기술 개발

장유현 한국에너지학회 2017 한국에너지공학회 학술발표회 Vol.2017 No.9

Study on Alignment Estimation of Nuclear Fuel Bundle in Spent Fuel Pool with Multi-Ultrasound Signal Analysis

장유현 한국정밀공학회 2016 International Journal of Precision Engineering and Vol.17 No.11

In the Wolsung nuclear power plant, workers move the spent fuel bundles that have been maintained in the water to reduce the radiation level and temperature for several years. Spent fuel bundles under 5m of boron water are moved into a dry container with the naked eye. Therefore, it is not easy to maneuver the spent fuel bundle gripper (hereafter gripper) to the center of the spent fuel bundle with the naked eye. If a spent fuel bundle is hit by approaching the spent fuel bundle, there is a risk that some fuel rods will be separated. This study suggests a technique to prevent the collision of the gripper and a spent fuel bundle. An ultrasound sensor is used for the inspection of high radiation nuclear power plant components such as nuclear reactor pipes, and nuclear fuel rods in light-water nuclear power plants. An ultrasound beam field is calculated to select the frequency of ultrasound performance such as the near-field length and directivity. A test bed is fabricated with a multi-channel ultrasound system. Variation of peak amplitude with the lateral offset is analyzed to obtain the information of lateral offset and the deviation of normalized peak values of four ultrasound sensors used to derive the direction of offset.

원전 취수구 뻘 퇴적높이 측정로봇 개발

장유현,민지호 한국에너지학회 2017 한국에너지공학회 학술발표회 Vol.2017 No.9

복강내 종괴로 나타난 닭뼈에 의한 장천공 1 예

양대현,김태형,임선희,장유현,김형완,김준완,김봉룡,박정진,이계희 대한소화기학회 2001 대한소화기학회지 Vol.38 No.1

Ingestion of foreign bodies occurs commonly in young children and emotionally disturbed individuals. Predisposing factors include decreased palatal sensitivity by dentures, excessive alcohol intake or drug use. Despite the incredible number and variety of objects, most ingested foreign bodies pass through the gastrointestinal tract, but the cases fewer than 1% result in perforation. The clinical manifestations of perforation include peritonitis, abscess, inflammatory mass, fistula, obstruction, and hemorrhage. Because most symptoms mimic the other common intraabdominal conditions, and many patients can not recall the ingested materials, preoperative diagnosis is difficult. The greastest number of perforations occur in appendix, the ileocecal region and Meckel`s diverticula. The remainders are scattered throughout the gastrointestinal tract, with a slightly higher incidence in the sigmoid colon. We present here a case of colonic perforation by an ingested chicken bone presenting as an intraabdominal inflammatory mass. The diagnosis was confirmed by laparoscopic surgery.

대량 출혈을 동반한 위유암종 1예

남수연,박란영,이지현,이창수,정의준,장유현,임선희,양대현,노은진,김나래 대한소화기내시경학회 2002 Clinical Endoscopy Vol.24 No.3

유암종은 위장점막에 분포하는 장크롬친화성 세포에서 기원한다. 유암종은 대부분 무증상이며 대량출혈을 동반하는 위유암종은 드물다. 저자는 흑색변과 현훈으로 입원한 환자에서 위유암종을 1예 경험하였다. 식도위십이지장경 검사에서 위체하부에 궤양성 융기 병변이 보여 진행성위암 Borrman III형 소견을 보였다. 조직 현미경 검사에서 악성 세포가 없는 양성 위궤양으로 보여졌다. 반복 조직 현미경 검사 역시 같은 결과였다. 복부 전산화 단층 촬영은 다수의 위주변부 림프절 비대를 동반한 위의 종양을 보였다. 위절제술 후 얻은 조직 현미경 검사에서 위유암종으로 드러났다. 저자 등은 내시경 소견은 진행성 위암의 형태를 보이고, 대량 출혈을 동반한 위유암종 1예를 보고한다. Carcinoid tumors originate from the enterochromaffin cells that are located in the gastrointestinal mucosa. Most of these tumors are asymptomatic and gastric carcinoid with massive gastrointestinal bleeding is found rarely. We experienced a case of gastric carcinoid admitted to our hospital due to melena and dizziness. The esophagogastroduodenoscopic examination revealed an ulcerofungating mass in the lower body which was thought to be a Borrmann type III adenocarcinoma. Microscopic examination of the biopsy specimens showed benign gastric ulcer without malignant cells. Repeated endoscopic biopsy revealed the same results. A computed tomographic scan of the abdomen showed a gastric mass with multiple perigastric enlarged lymph nodes. Histopathological examination of the operative specimen showed gastric carcinoid. We report a case of gastric carcinoid with massive bleeding mimicking advanced gastric cancer. (Korean J Gastrointest Endosc 2002;24:161-165)