Safeguards Distinction in Water-Cooled SMRs

Kwangho Ju,Seungho Jeong,Hosik Yoo 한국방사성폐기물학회 2023 한국방사성폐기물학회 학술논문요약집 Vol.21 No.2

Small modular reactors (SMRs) are getting attention as an alternative to fossil fuel power stations due to versatile application and carbon dioxide reduction. Although various types of advanced reactors are being developed, water-cooled SMR will be first deployed on a commercial scale. The International Atomic Energy Agency (IAEA) and regulatory bodies are trying to identify safeguards issues of water-cooled SMRs as the first priority. IAEA begins to develop a safeguards plan by asking for the facility’s specification in a given format, a design information questionnaire (DIQ). Then, IAEA periodically performs safeguards activities such as design information verification (DIV) and physical inventory verification (PIV). In this sense, we utilize research and power reactor DIQ for water-cooled SMRs (NuScale, SMART, i-SMR and KLT-40S). Most of the questions are answered with open information. For undisclosed answers, pressurized water reactor (PWR) features are described. Safeguards issues in water-cooled SMR originate from core modularization. As the nuclear material flows are diversified, the number of safeguards measure will be increased while staff are reduced in SMRs. Instrumentation for safeguards should be developed to reduce worker’s fatigue level. Intensive arrangement of fuel assemblies may also need unique devices to secure their visibility or detectability. A transparent floor with a surveillance system or advanced Cherenkov viewing device may be adopted to enhance containment and surveillance. Meanwhile, some questions could be more elaborate regarding safeguards. First, question #38 cannot confirm the time of occurrence of weapon-grade plutonium for reactor operation. Second, the answers in questions #46 and #49 are primitive to identify a place to generate an undeclared fissile material. Therefore, the current DIQ should be revised to get a detailed burnup report and spatial distribution of neutron flux.

2천년대 이후 한국 대중가요의 정서변화

주광호 ( Kwangho Ju ) 사단법인 아시아문화학술원 2021 인문사회 21 Vol.12 No.5

이 논문은 2000년대 이후 연도별 대중가요 정서의 변화 이유를 살펴보고 향후 대중가요 발전의 방향성을 제시하는 것이 연구목적이다. 이를 위해 2010년 이후 멜론인기차트 기준으로 총 90곡을 선정하여 가사에 나타난 정서표현의 단어들을 추려내어 5개 범주(소재, 주체, 현실인식, 표현기법, 외로움)로 나누어 분석하였다. 연구 결과 첫째, 음악 향유에 있어서 과학기술의 발달로 시·공간적 제약이 없어지고, 다종다양한 대중가요 청취가 가능해짐으로써 대중의 취향 또한 다종다양하게 발전하였다. 둘째, 2010년 이후 한국 대중가요는 새로운 유행어의 등장, 아이돌시장의 확대, 정치·경제·문화적 이슈에 따른 사회분위기에 가장 큰 영향을 받는 것으로 나타났다. 이로써 대중가요 가사 흐름의 변화를 통해 대중의 정서변화의 흐름을 유추할 수 있어 이후 대중가요 방향성을 제시하였다. The purpose of this thesis is to examine the reasons for the change of popular music sentiment by year since the 2000s and to suggest the direction of the future development of popular music. For this purpose, a total of 90 songs were selected based on the Melon Popularity Chart since 2010, and the words of emotional expression lyrics were extracted and analyzed by 5 categories (materials, subject, reality perception, expression technique, loneliness). As the research results first, people’s taste have evolved in quite various ways in terms of the enjoyment of music as the advancement of science and technology leads to the removal of temporal and spatial restrictions and makes it possible to listen to a wide variety of popular songs. second, it’s found that in and after 2010, Korean popular songs were under the largest influence of social climate including the emergence of new fad words, the expansion of the idol market and political, economic and cultural issues. Therefore the flow of public sentiment can be inferred through the change in the flow of popular song lyrics, so the direction of popular music presented.

High-speed DAC transmitter using digital-based Feed Forward Equalizer

Kwangho Lee,Sung-gon shin,Haram Ju 대한전자공학회 2023 대한전자공학회 학술대회 Vol.2023 No.11

Vascular Calcification in Patients Undergoing Total Knee Arthroplasty: Frequency and Effects on the Surgery

Ju-Hyung Yoo,Jin-Gyu Kim,Kwangho Chung,Seung Hyun Lee,Hyun-Cheol Oh,Sang-Hoon Park,Sang-Ok Seok 대한정형외과학회 2020 Clinics in Orthopedic Surgery Vol.12 No.2

Background: This study aims to investigate the frequency of distal femoral and popliteal arterial calcification and to evaluate the intraoperative and postoperative effects of arterial calcification in patients undergoing total knee arthroplasty using a tourniquet. Methods: The records of 5,438 patients who had undergone primary total knee arthroplasty between January 2003 and January 2017 were retrospectively reviewed. We examined the preoperative radiographs of the knee from all patients for calcifications of the femoral and popliteal arteries. Vascular calcification was identified on preoperative radiographs in 223 cases. Intraoperative and postoperative complications were investigated among these patients. Postoperative complications were analyzed from the time of surgery to the last follow-up (minimum 1-year follow-up). Results: Vascular calcification of the arteries around the knee was found in 223 cases (4.1%). The mean patient age was 70.6 years in the non-calcification group and 73.8 years in the calcification group (p > 0.05). The calcification group was classified into medial, intimal, or mixed subgroups according to the morphology of calcification on preoperative radiographs. The medial type included 46 cases (20.6%); intimal type, 161 cases (72.2%); and mixed type, 16 cases (2.7%). There was no statistically significant difference in demographic and surgical data among the three groups. There were intraoperative complications in two cases in the medial type group, both of which involved tourniquet failure. There was also a postoperative complication in one case in the medial type group, which involved wound dehiscence at 2 weeks postoperatively. No other postoperative complications were identified during 1-year follow-up. Conclusions: Despite the presence of calcifications in the arteries around the knee, total knee arthroplasty (using a tourniquet) can be performed without serious complications.

지능형 영상 감시 시스템에서 사람 자세 추정을 이용한 납치 상황 인식

박주현(Ju Hyun Park),송광호(KwangHo Song),김유성(Yoo-Sung Kim) 한국컴퓨터정보학회 2018 韓國컴퓨터情報學會論文誌 Vol.23 No.8

In this paper, a kidnapping detection scheme in which human pose estimation is used to classify accurately between kidnapping cases and normal ones is proposed. To estimate human poses from input video, human’s 10 joint information is extracted by OpenPose library. In addition to the features which are used in the previous study to represent the size change rates and the regularities of human activities, the human pose estimation features which are computed from the location of detected human’s joints are used as the features to distinguish kidnapping situations from the normal accompanying ones. A frame-based kidnapping detection scheme is generated according to the selection of J48 decision tree model from the comparison of several representative classification models. When a video has more frames of kidnapping situation than the threshold ratio after two people meet in the video, the proposed scheme detects and notifies the occurrence of kidnapping event. To check the feasibility of the proposed scheme, the detection accuracy of our newly proposed scheme is compared with that of the previous scheme. According to the experiment results, the proposed scheme could detect kidnapping situations more 4.73% correctly than the previous scheme.

1/4 파장 공명기에서 하향 전파하는 예혼합 화염의 열음향장에 관한 실험적 고찰

손광호(Kwangho Son),석지원(Jiwon Seok),이원주(Won-Ju Lee),윤성환(Sung Hwan Yoon) 한국연소학회 2019 KOSCOSYMPOSIUM논문집 Vol.2019 No.11

새로운 초고압 송전선로 친환경설계프로그램 TLCALC

梁光鎬(Kwangho Yang),朱玧魯(Munno Ju),明聖鎬(Sungho Myung),吉暻碩(Gyungsuk Kil),黃琪鉉(Gihyun Hwang),李東一(Dongil Lee) 대한전기학회 2006 전기학회논문지A Vol.55 No.4

HVAC transmission lines must be designed to satisfy environmental regulations. Therefore it is necessary to pre-evaluate environmental problems for transmission line designer using prediction program. In this study, environmental design software, TLCALC(Transmission Line CALCulation) for transmission lines was developed as a comprehensive window program. It has 6 modules that are audible noise, radio noise, television noise, magnetic field, electric field and conductor surface gradient. TLCALC solved a few problems in use of the existing foreign tools and took several advantages as follows; ① It is a common tool that solves calculating limitations of foreign formulas, ② It has wide application ranges and enhances accuracy of prediction. ③ It can be applied to almost transmission line configurations in Korea. ④ Experienced designers can get the results of calculation within about 15 minutes. Because the use of TLCALC is easy and practical, this program will be usefully applied to the environmental friendly design and construction of transmission lines. In the future, it is expected that public complaints and social environmental cost will be reduced by the use of TLCALC.

초고압 직류 가공송전 후보 도체방식의 이온류 환경특성 코로나 케이지 모의시험

朱玧魯(Munno Ju),梁光鎬(Kwangho Yang),李東一(Dongil Lee),申玖容(Kooyong Shin) 대한전기학회 2007 전기학회논문지 Vol.56 No.10

Small ions generated at conductor corona sources remain in the atmosphere until they recombine with ions of opposite polarity, attach to aerosols, or make contact with an object. Ion current density is major factor to design conductor configuration of DC overhead transmission line. Several techniques have been used to measure the ion current of HVDC overhead transmission line. In this study, the ion current density was measured by a plate electrode made of a metal flat board at DC corona cage. The sensitivity of the plate electrode is 0.156㎂/㎡/V. To obtain an useful database on corona discharge, it is necessary to do corona test on several kinds of conductor bundles. Therefore, a number of experiments were conducted on several kinds of conductor bundles. To reliably analyze ion effects, corona cage test data were obtained over a long period of time under various weather conditions and expressed as a statistical distribution. Ion current density distribution in foul weather shows a significant increase in levels over the corresponding fair weather. Based on this results, we evaluated the environmental characteristic caused by ion flow of three candidated conductor bundles.

HVDC ±500 ㎸ 가공 송전선로의 최적 도체방식 선정을 위한 전기환경특성 평가

朱玧魯(Munno Ju),吉暻碩(Gyungsuk Kil),梁光鎬(Kwangho Yang),李性斗(Sungdoo Lee),黃琪鉉(Gihyun Hwang) 대한전기학회 2006 전기학회논문지C Vol.55 No.11

Corona interferences, such as radio noise, audible noise and television noise, need to be taken into account in the design of HVDC transmission line conductor configuration. Therefore the line designer requires data from which to estimate the corona performance of any set of conductors. To get a sufficiently complete set of design data, it is necessary to examine the corona test of a large number of conductor geometries. This paper presents the results of corona cage test among three types of candidate conductors. It is quite clear from test results that the conductor geometries play an important role in establishing the magnitude of corona noise. Corona noise data from corona cage test are expressed as a statistical distribution of results obtained over long periods of time and various weather conditions. Therefore we can determine an environmentally-friendly conductor bundle for HVDC overhead transmission line. Based on this finding results, various simulations about HVDC line configurations, such as pole space and pole height, will be conducted. And then finally an optimal configuration for HVDC transmission line will be decided.

초고압 직류 가공 송전선로에서 발생되는 이온 계측시스템 개발

朱玧魯(Munno Ju),梁光鎬(Kwangho Yang),李東一(Dongil Lee),申玖容(Kooyong Shin),林才燮(Jaeseop Lim) 대한전기학회 2008 전기학회논문지 Vol.57 No.11

The electrical discharge of high voltage direct current(HVDC) overhead transmission line generate audible noise, radio noise, electric field, ion current and induced voltage on the ground. These items are major factors to design environmentally-friendly configuration of DC transmission line. Therefore, HVDC transmission lines must be designed to keep all these corona effects within acceptable levels. Several techniques have been used to assess interference caused by ions on HVDC overhead transmission line. In this study, to assess the ion characteristic of DC line, the ion current density and induced voltage caused by ion flow were measured by plate electrodes manufactured from a metal flat board and charged bodies, respectively. The charged body has two types of cylinder and cylindrical plate. From the results of calibration experiments, the sensitivity of flat electrode and charged body can be obtained. At present, the developed system is used to investigate the ion generation characteristics of Kochang DC ±500㎸ test line.