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Application and optimal design of the bionic guide vane to improve the safety serve performances of the reactor coolant pump

  • Liu, Haoran;Wang, Xiaofang;Lu, Yeming;Yan, Yongqi;Zhao, Wei;Wu, Xiaocui;Zhang, Zhigang
    • Nuclear Engineering and Technology
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    • v.54 no.7
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    • pp.2491-2509
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    • 2022
  • As an important device in the nuclear island, the nuclear coolant pump can continuously provide power for medium circulation. The vane is one of the stationary parts in the nuclear coolant pump, which is installed between the impeller and the casing. The shape of the vane plays a significant role in the pump's overall performance and stability which are the important indicators during the safety serve process. Hence, the bionic concept is firstly applied into the design process of the vane to improve the performance of the nuclear coolant pump. Taking the scaled high-performance hydraulic model (on a scale of 1:2.5) of the coolant pump as the reference, a united bionic design approach is proposed for the unique structure of the guide vane of the nuclear coolant pump. Then, a new optimization design platform is established to output the optimal bionic vane. Finally, the comparative results and the corresponding mechanism are analyzed. The conclusions can be gotten as: (1) four parameters are introduced to configure the shape of the bionic blade, the significance of each parameter is herein demonstrated; (2) the optimal bionic vane is successfully obtained by the optimization design platform, the efficiency performance and the head performance of which can be improved by 1.6% and 1.27% respectively; (3) when compared to the original vane, the optimized bionic vane can improve the inner flow characteristics, namely, it can reduce the flow loss and decrease the pressure pulsation amplitude; (4) through the mechanism analysis, it can be found out that the bionic structure can induce the spanwise velocity and the vortices, which can reduce drag and suppress the boundary layer separation.

Acupuncture Treatment for Patellofemoral Pain Syndrome: A Protocol for a Systematic Review (슬개대퇴통증증후군의 침 치료에 대한 체계적 문헌고찰의 프로토콜)

  • Ji, Min Jun;Ser, Kyung Jun;Kim, Ho Geol;Gu, Ji Hyang;Ha, Hyun Ju;Oh, Min Seok
    • Journal of Korean Medicine Rehabilitation
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    • v.32 no.3
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    • pp.29-35
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    • 2022
  • Objectives The purpose of this systematic review is to analyse randomized controlled trials about acupuncture for patellofemoral pain syndrome (PFPS) and evaluate it's pain improvement effect. Methods Studies will be searched from ten databases (Medline/PubMed, Cochrane Library, EMBASE, China National Knowledge Infrastructure [CNKI], WanFang Data, Citation Information by NII [CiNII], ScienceON, Koreanstudies Information Service System [KISS], KMBASE, and KoreaMed). Participants will be patients diagnosed with PFPS, regardless of cause, gender, age or race, and interventions will be acupuncture, electroacupuncture, dry needling, fire needle, and acupotomy. Other treatments than interventions will be the control group and the main outcome will be reviewed by visual analogue scale (VAS). Results Data will be extracted and assessed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis flow chart and Cochrane risk of bias tools. Meta-analysis will be conducted using random effect model within 95% confidence interval. Conclusions We expect this systematic review to provide useful data about the pain improvements of patellofemoral pain using acupuncture and expect to stimulate and systematize acupuncture treatment on PFPS in the future.

Similarities and Differences in Patients under Aged 18 with Respiratory Disease on Emergency Departments: Before and after COVID-19 Outbreak (코로나19 전·후 응급실로 내원한 소아청소년 호흡기계 환자의 유사점과 차이점)

  • Huh, Young-Jin;Pak, Yun-Suk;Kim, Eun-Ah;Oh, Mi-Ra
    • Health Policy and Management
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    • v.32 no.2
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    • pp.164-172
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    • 2022
  • Background: The purpose of this study was to the impact of the coronavirus disease 2019 (COVID-19) outbreak on emergency departments (EDs) in patients under the age of 18 years with respiratory disease. Also, we analyzed similarities and differences in patients including revisit before and after the COVID-19 outbreak. Methods: This study population was respiratory patients under the age of 18 years who visited all 403 EDs in Korea between January 1st, 2019 and December 31st, 2020, using the National Emergency Department Information System Database. The primary outcome was the number of respiratory patients according to age, sex, the type of EDs, season, Korean Triage and Acuity Scale (KTAS) levels, the result of ED, and length of stay. The secondary outcome was the number of revisit respiratory patients within 72 hours. We calculated the risk-adjusted revisit rates according to the KTAS level using a multiple logistic regression model. Results: The number of ED visits decreased from 274,526 in 2019 to 79,007 in 2020; this number was 71.2% lower than that before COVID-19. In spring 2020, this number was 90.1% lower than during the same period in 2019. For the revisit rate in the study population, the adjusted odds ratio (95% confidence interval) was 1.22 (1.05-1.41) in 2019 and 1.39 (1.07-1.81) in 2020. Conclusion: Implementing appropriate emergency care policies in severe respiratory patients would have contributed to improving the safety of reducing in revisit rate.

A Study for Integrating ICS Security Logs with Centralized SIEM (Security Information and Event Management) using OPC Protocol (OPC 프로토콜을 활용한 제어시스템 보안로그 전송방법 고찰 및 통합 로그서버 구축방안)

  • Kim, Jaehong;Park, Yongsuk
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.26 no.8
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    • pp.1205-1212
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    • 2022
  • Cyber threat targeting ICS (Industrial Control System) has indicated drastic increases over the past decade and Cyber Incident in Critical Infrastructure such as Energy, Gas Terminal and Petrochemical industries can lead to disaster-level accidents including casualties and large-scale fires. In order to effectively respond to cyber attacks targeting ICS, a multi-layered defense-in-depth strategy considering Control System Architecture is necessary. In particular, the centralized security log system integrating OT (Operational Technology) and IT (Information Technology) plays an important role in the ICS incident response plan. The paper suggests the way of implementing centralized security log system that collects security events and logs using OPC Protocol from Level 0 to Level 5 based on IEC62443 Purdue Model to integrate ICS security logs with SIEM (Security Information Event Management) operated in IT environment.

Nutritional composition of various insects and potential uses as alternative protein sources in animal diets

  • Shah, Assar Ali;Totakul, Pajaree;Matra, Maharach;Cherdthong, Anusorn;Hanboonsong, Yupa;Wanapat, Metha
    • Animal Bioscience
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    • v.35 no.2_spc
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    • pp.317-331
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    • 2022
  • The aim of the present investigation is to determine the nutritional composition of various insects and their potential uses as alternative protein sources in animal diets. The feeding industry requires production systems that use accessible resources, such as feed resources, and concentrates on the potential impacts on production yield and nutritional quality. Invertebrate insects, such as black soldier flies, grasshoppers, mealworms, housefly larvae, and crickets, have been used as human food and as feed for nonruminants and aqua culture while for ruminants their use has been limited. Insects can be mass-produced, participating in a circular economy that minimizes or eliminates food- and feed-waste through bioconversion. Although the model for formula-scale production of insects as feed for domestic animals has been explored for a number of years, significant production and transformation to being a conventional protein resource remains to be deeply investigated. This review will focus on the nutritional composition of various insects and their potential use as alternative protein sources, as well as their potential use to promote and support sustainable animal production. Furthermore, nutritional compositions, such as high protein, lauric acid omega 6, and omega 3, and bioactive compounds, such as chitin, are of great potential use for animal feeding.

CALS: Channel State Information Auto-Labeling System for Large-scale Deep Learning-based Wi-Fi Sensing (딥러닝 기반 Wi-Fi 센싱 시스템의 효율적인 구축을 위한 지능형 데이터 수집 기법)

  • Jang, Jung-Ik;Choi, Jaehyuk
    • Journal of IKEEE
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    • v.26 no.3
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    • pp.341-348
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    • 2022
  • Wi-Fi Sensing, which uses Wi-Fi technology to sense the surrounding environments, has strong potentials in a variety of sensing applications. Recently several advanced deep learning-based solutions using CSI (Channel State Information) data have achieved high performance, but it is still difficult to use in practice without explicit data collection, which requires expensive adaptation efforts for model retraining. In this study, we propose a Channel State Information Automatic Labeling System (CALS) that automatically collects and labels training CSI data for deep learning-based Wi-Fi sensing systems. The proposed system allows the CSI data collection process to efficiently collect labeled CSI for labeling for supervised learning using computer vision technologies such as object detection algorithms. We built a prototype of CALS to demonstrate its efficiency and collected data to train deep learning models for detecting the presence of a person in an indoor environment, showing to achieve an accuracy of over 90% with the auto-labeled data sets generated by CALS.

Reducing pain and opioid consumption after body contouring of the breast by application of a perioperative nerve block: a systematic review

  • Asserson, Derek B.;Sahar, David E.
    • Archives of Plastic Surgery
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    • v.48 no.4
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    • pp.361-365
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    • 2021
  • Background Pain in the postoperative body contouring patient has traditionally been managed with narcotic medication. In an effort to minimize side effects and prevent addiction, plastic surgeons are searching for novel ways to provide adequate analgesia, one of which is nerve blocks. This study was conducted with a meta-analysis that evaluates the efficacy of these blocks for patients who undergo breast surgery. Methods A search of the PubMed/MEDLINE database for articles including the terms "post-operative analgesia" OR "postoperative pain management" AND "in plastic surgery" OR "in cosmetic surgery" OR "in elective surgery" in February 2019 generated five studies on elective breast augmentation and reduction mammoplasty that reported pain scores and quantities of opioids consumed. Independent samples t-tests, one-way analysis of variance, and a random effects model were implemented for evaluation. Results A total of 317 patients were identified as having undergone body contouring of the breast, about half of which received a nerve block. Pain scores on a 1-10 scale and opioid dose-equivalents were calculated. Those who were blocked had an average score of 2.40 compared to 3.64 for those who did not (P<0.001), and required an average of 5.20 less narcotic doses (P<0.001). Pain relief following subpectoral augmentation was best achieved with type-II blocks as opposed to type-I and type-II with serratus plane (P<0.001). Conclusions The opioid epidemic has extended to all surgical specialties. Implementation of a nerve block seems to be an efficacious and cost-effective mechanism to not only help with post-operative pain, but also lower the need for narcotics, especially in subpectoral augmentation.

Simulation of Water Redistribution for the Resized Beneficiary Area of a Large Scale Agricultural Reservoir (대규모 농업용저수지 수혜면적 변화에 따른 효율적 용수재분배 모의)

  • Sung, Muhong;Jeung, Minhyuk;Beom, Jina;Park, Taesun;Lee, Jaenam;Jung, Hyoungmo;Kim, Youngjoo;Yoo, Seunghwan;Yoon, Kwangsik
    • Journal of The Korean Society of Agricultural Engineers
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    • v.63 no.3
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    • pp.1-12
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    • 2021
  • Optimal water management is to efficiently and equally supply an appropriate amount of water by using irrigation facilities. Therefore, it is necessary to evaluate water supply capacity through distribution simulation between the designed distribution rate and re-distributed rate according to the changed farming conditions. In this study, we recalculated the agricultural water supply amount of Geumcheon main canal, which beneficiary area was reduced due to the development of Gwangju-Jeonnam innovation city, and we constructed a canal network using the SWMM model to simulate the change in supply rate of each main canal according to the re-distributed rate. Even though the supply amount of the Geumcheon main canal was reduced from 1.20 m3/s to 0.90 m3/s, it showed a similar supply rate to the current, and the reduced quantity could be supplied to the rest of the main canal. As a result, the arrival time at the ends of all main canal, except for the Geumcheon main canal, decreased from 1 to 3 hours, and the supply rate increased from 4 to 17.0% at the main canal located at the end of the beneficiary area of Naju reservoir.

Importance-Performance Analysis of Mountain Village Promotion Projects in the Forest Sector by Upper-Level Local Governments

  • Kang, Byung-Hoon;Kim, Seong-Hak;Chae, Jin-Hae
    • Journal of People, Plants, and Environment
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    • v.24 no.6
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    • pp.707-718
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    • 2021
  • Background and objective: Due to the recent crisis of extinction in local areas, the mountain village promotion policy is recognized as an important task. This study examined the priorities of major policy projects in the forest sector that affect mountain village promotion. Methods: For research methods, literature search, expert advisory meetings, and a survey were conducted. The survey was conducted on 42 policy stakeholders from June 1 to August 13, 2021. The literature search was based on policy projects in the forest sector by 8 upper-level local governments including mountain villages. For questionnaire items, 173 forest policy projects were classified into 27 types through expert review, and the importance and performance of each type were rated on a 5-point Likert scale. Paired t-test, IPA, Locus for Focus model, and Borich needs assessment were used as the analysis methods, and the statistical program SPSS 21.0 was used as the analytical tool. Results: The results showed that 'creating forest-related jobs' and 'supporting cultivation of professional forestry workers' both showed high importance and performance, implying that they would show an effect in mountain village promotion. 'Creating forests for environmental improvement', 'discovering forest cultural assets' 'establishing and boosting forest tourism', 'providing forest therapy services', 'creating forest-related jobs', 'supporting community revitalization', and 'urban-rural exchanges' were found to be the types that needed improvement and concentration for mountain village promotion. In particular, 'creating forests for environmental improvement' and 'discovering forest cultural assets' were derived as priority considerations for mountain village promotion policies. Conclusion: In summary, it was found that in order to promote mountain villages, various content projects must be improved and carried out to enhance the physical environment and revitalize mountain villages.

A case study of gust factor characteristics for typhoon Morakat observed by distributed sites

  • Liu, Zihang;Fang, Genshen;Zhao, Lin;Cao, Shuyang;Ge, Yaojun
    • Wind and Structures
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    • v.35 no.1
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    • pp.21-34
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    • 2022
  • Gust factor is an important parameter for the conversion between peak gust wind and mean wind speed used for the structural design and wind-related hazard mitigation. The gust factor of typhoon wind is observed to show a significant dispersion and some differences with large-scale weather systems, e.g., monsoons and extratropical cyclones. In this study, insitu measurement data captured by 13 meteorological towers during a strong typhoon Morakot are collected to investigate the statistical characteristics, height and wind speed dependency of the gust factor. Onshore off-sea and off-land winds are comparatively studied, respectively to characterize the underlying terrain effects on the gust factor. The theoretical method of peak factor based on Gaussian assumption is then introduced to compare the gust factor profiles observed in this study and given in some building codes and standards. The results show that the probability distributions of gust factor for both off-sea winds and off-land winds can be well described using the generalized extreme value (GEV) distribution model. Compared with the off-land winds, the off-sea gust factors are relatively smaller, and the probability distribution is more leptokurtic with longer tails. With the increase of height, especially for off-sea winds, the probability distributions of gust factor are more peaked and right-tailed. The scatters of gust factor decrease with the mean wind speed and height. AS/NZ's suggestions are nearly parallel with the measured gust factor profiles below 80m, while the fitting curve of off-sea data below 120m is more similar to AIJ, ASCE and EU.