• Title/Summary/Keyword: center of the series

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Even Harmonic Analysis of Series Arc-fault Current Using BPF of GIC Application in Computer (GIC 적용 대역통과필터를 이용한 컴퓨터 부하의 직렬 아크고장 전류 우수고조파 분석)

  • Ko, Won-Sik;Moon, Won-Sik;Bang, Sun-Bae;Kim, Jae-Chul
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.10
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    • pp.1554-1560
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    • 2012
  • In this paper, the even harmonic current(2nd, 4th, 6th, 8th) of the arc fault current and normal current were measured in computer load and analyzed. The BPF with GIC was developed to detection of harmonic, the exact center frequency and a high degree of sharpness could be easily obtained. The total even harmonic distortion due to series arc fault in computer load was 31.2%, this value was increased 3.9 times better than the total even harmonic distortion of normal current. The results of analysis of arc fault current RMS variation rate and Peak variation rate per half-cycle, The RMS average variation rate are as follows ; the 2nd harmonic was 0.24, the 4th harmonic was 0.15, the 6th harmonic was 0.19, the 8th harmonic was 0.25, respectively. The Peak average variation rate are as follows ; the 2nd harmonic was 0.19, the 4th harmonic was 0.12, the 6th harmonic was 0.13, the 8th harmonic was 0.15, respectively. The results of this analysis utilize data to detect of series arc fault on wiring of computer load.

Controversial Point and Improvement Policy of the Certified System for Quality -Based on the Relation with ISO 9000 Series- (품질인증제도(品質認證制度)의 문제점(問題點)과 개선방안(改善方案) -ISO 9000번대(番代)와 연계(連繫)를 중심(中心)으로-)

  • Jo, Nam-Ho
    • Journal of Korean Society for Quality Management
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    • v.21 no.1
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    • pp.1-10
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    • 1993
  • The original purpose to introduce the system for quality certification by ISO 9000 series to our nation is basically promote the civilization interchanges among the various nations. we can't help regarding that the free trade is well performed to only a party and region to an agreement, but existed the possibility of being taken advantage of a means to the exclusive limiting import on the other regions. Under the considering the above situation, this study suggest that, the usuable policies of our domestic manufacturing corporations for acquiring the certification for the quality assurance of ISO 9000 series are as followings : 1) Using the civil and national diplomatic channel for the mutual assurance among the authorized agency of certification. 2) Gradually decreasing the difference between ISO 9000 and our nation in quality certification and solving the some problems as organizing the related research center. 3) In the post management of certified corporations, intentionally performing by using the authorized national agency from the ISO Headquarter and continuously reforming the related laws and regulations standardizing around the ISO series.

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Variation Characteristics of Annual Maximum Rainfall Series and Frequency-Based Rainfall in Korea (우리나라 연최대치 강우량 계열 및 확률강우량의 변화 특성)

  • Kim, Jae-Hvung
    • Journal of Wetlands Research
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    • v.4 no.2
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    • pp.43-56
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    • 2002
  • About 12 rain gauge stations of Korea, annual maximum rainfall series of before and after 1980 whose durations are 1, 2, 3, 6, 12, 24, 48, 72 hours respectively were composed and statistical characteristics of those time series were calculated and probability rainfall were estimated by L-moment frequency analysis method and compared each other in order to investigate the recent quantitative rainfall variations. And also, distribution curves of each statistical variations for each duration were constructed by using Kigging method to look into spacial rainfall variation aspects. As a result, We could confirm recent rainfall increase in the South Korea. And spatial increase pattern of standard deviation and frequency rainfall appeared analogously each other. 1n the cases of comparatively short rainfall duration, we could see relatively low increase or decrease tendency in Chungchong Province, Cholla-bukdo, Cholla-namdo eastern part, Kyongsang-namdo western part area. While, variations happened great1y in seaside district of east coast, southwest seashore, Inchon area etc. In the cases of longer durations relatively low increase was showed in southern seashore such as Yeosoo area and as distance recedes from this area, showed gradually augmented tendency. The aspect of mean looks similar tendency of above except that the variation rate of almost seaside district are big in the case of shorter durations. In addition, rainfall increases of short durations which became the center of hydrologist and meteorologist are unconfirmed in this study.

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Condition assessment of stay cables through enhanced time series classification using a deep learning approach

  • Zhang, Zhiming;Yan, Jin;Li, Liangding;Pan, Hong;Dong, Chuanzhi
    • Smart Structures and Systems
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    • v.29 no.1
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    • pp.105-116
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    • 2022
  • Stay cables play an essential role in cable-stayed bridges. Severe vibrations and/or harsh environment may result in cable failures. Therefore, an efficient structural health monitoring (SHM) solution for cable damage detection is necessary. This study proposes a data-driven method for immediately detecting cable damage from measured cable forces by recognizing pattern transition from the intact condition when damage occurs. In the proposed method, pattern recognition for cable damage detection is realized by time series classification (TSC) using a deep learning (DL) model, namely, the long short term memory fully convolutional network (LSTM-FCN). First, a TSC classifier is trained and validated using the cable forces (or cable force ratios) collected from intact stay cables, setting the segmented data series as input and the cable (or cable pair) ID as class labels. Subsequently, the classifier is tested using the data collected under possible damaged conditions. Finally, the cable or cable pair corresponding to the least classification accuracy is recommended as the most probable damaged cable or cable pair. A case study using measured cable forces from an in-service cable-stayed bridge shows that the cable with damage can be correctly identified using the proposed DL-TSC method. Compared with existing cable damage detection methods in the literature, the DL-TSC method requires minor data preprocessing and feature engineering and thus enables fast and convenient early detection in real applications.

Advanced Maximum Power Point Tracking Method for the Series Operation Strategy of Grid-Connected Small Wind Turbines (계통연계형 소형풍력발전 시스템의 직렬운전을 고려한 개선된 MPPT 방법)

  • Kim, Yong-Hyu;Heo, Hong-Jun;Kim, Jang-Mok
    • The Transactions of the Korean Institute of Power Electronics
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    • v.21 no.6
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    • pp.497-505
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    • 2016
  • Operating wind turbine generators at maximum power point requires maximum power point tracking (MPPT) control methods. However, conventional methods cannot track the appropriate maximum power point in situations involving wind turbine systems based on a series operation strategy. These systems comprise one or more local maximum power points, and conventional methods can detect only one local maximum power point closed by a current operation point. This study proposes an advanced MPPT method for the series operation strategy of a small, grid-connected wind turbine system. In determining the appropriate maximum point, operations at certain local maximum power points are analyzed. The results show one appropriate point, which is tracked by the proposed MPPT method. The effectiveness of the proposed method is verified by the experimental results.

Study on was serialized in The Korea Magazine 「KOREA'S NOTED WOMEN」 (『The Korea Magazine』의 「한국에서 이름난 여성들」 연재물에 관한 연구)

  • Choi, yun-hi
    • Cross-Cultural Studies
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    • v.37
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    • pp.185-209
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    • 2014
  • This paper is a study on The Korea Magzine. The magazine has a series. One of them is KOREA'S NOTED WOMEN. This is the women who are all Chinese women. They are Yo-WHA-SI(여와씨), A-WHANG, YU-YUNG(아황과 여영), T'AI-IM AND T'AI-SA(태임과 태사), WANG SO-KOON(왕소군), Su Wang Mo(서왕모), Yang Kwi-pi(양귀비), SU-SI(서시), TAK MOON-KOON(탁문군). The story of the women in the magazine were studied in a series of articles of reasons. First, it is because the Chinese women living in the hearts of Koreans. Second, the Koreans because these women want to love passionately, and be like. Third, because the Chinese women was also well-known in Korea as well known in East Asia. Was This series is used in any way. Features shown in the description was investigated. It explains how to understand what they Korea. Deliberately omitted, and were also added. I also used the analogy and comparison. This does not make sense but were accepted. Finally, we fully understand and take advantage of the literature.

Human Papillomavirus Vaccination for Foreigners during COVID-19 Era (COVID-19 시대에서 외국인의 자궁경부암 백신접종)

  • Lim, Juwon
    • Korean journal of aerospace and environmental medicine
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    • v.31 no.1
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    • pp.21-23
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    • 2021
  • Purpose: Human papillomavirus (HPV) vaccination schedule is recommended by Strategic Advisory Group of Experts on Immunization of World Health Organization to achieve high efficacy and immunogenicity. However, the patients often cannot keep up their schedule for several reasons. Methods: Monthly numbers of visitors for HPV vaccination between 2019 and 2021 were analyzed to measure the impact of coronavirus disease-19 (COVID-19) outbreak which was the main cause of this delay. Results: In February 2020, the number of foreign patients vaccinated with HPV was dropped suddenly due to COVID-19. Prior to this impact, the average patients per month for HPV vaccination was 160 (95% confidence interval [CI]: 143-176). It was then 30 (95% CI: 20-40). However recent trends show a gradual recovery. Conclusion: If a woman is pregnant after starting the HPV vaccine series, the reminder doses should be delayed until she is no longer pregnant. If this series is interrupted for any length of time, it can be resumed without restarting the series. HPV vaccine series need to be administered with a minimum interval of 14 days before or after administration of COVID-19 vaccines.

Analysis of Pollutant Characteristics in Nakdong River using Confirmatory Factor Modeling (확인적 요인모형을 이용한 낙동강 유역의 오염특성 분석)

  • Kim, Mi-Ah;Kang, Taegu;Lee, Hyuk;Shin, Yuna;Kim, Kyunghyun
    • Journal of Korean Society on Water Environment
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    • v.28 no.1
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    • pp.84-93
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    • 2012
  • The study was conducted to analyze the spatio-temporal changes in water quality of the major 36 sampling stations of Nakdong River, depending on each station, season using the 17 water quality variables from 2000 to 2010. The result was verified to interpret the characteristics of water quality variables in a more accurate manners. According to the Principal component analysis (PCA) and Exploratory factor analysis (EFA) results; the results of these analyses were identified 4 factors, Factor 1 (nutrients) included the concentrations of T-N, T-P, $NO_{3}-N$, $PO_{4}-P$, DTN, DTP for sampling station and season, Factor 2 (organic pollutants) included the concentrations of BOD, COD, Chl-a, Factor 3 (microbes) included the concentrations of F.Coli, T.Coli, and Factor 4 (others) included the concentrations of pH, DO. The results of a Cluster analysis indicated that Geumhogang 6 was the most contaminated site, while tributaries and most of the down stream sites of Nakdong River were mainly affected by each nutrients (Factor 1) and organic pollutants (Factor 2). The verification consequence of Confirmatory factor analysis (CFA) from Exploratory factor analysis (EFA) result can be summarized as follows: we could find additional relations between variables besides the structure from EFA, which we obtained through the second-order final modeling adopted in CFA. Nutrients had the biggest impact on water pollution for each sampling station and season. In particular, It was analyzed that P-series pollutant should be controlled during spring and winter and N-series pollutant should be controlled during summer and fall.

Design, Synthesis and Biological Activities of Novel Vanilloid Receptor Antagonists

  • Lee, Bo-Young;Suh, Young-Ger;Lee, Yong-Sil;Min, Kyung-Hoon;Kim, Jin-Kwan;Seung, Ho-Sun;Park, Young-Ho
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.244.1-244.1
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    • 2003
  • Advances in understanding of pain and analgesia have been made. Over the past few years, we have designed and synthesized a series of VR agonists, based on the structures of 12-HPETE and capsaicin. the natural VR agonist. But for the development of analgesic drugs, these synthetic VR agonists had problems like burning sensation. hypothermia. etc. So our recent studoes have focused on designs and syntheses of VR antagonists based on the structure of capsaicin(natural VR agonist), and capsazepine(synthetic VR antagonist). (omitted)

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Systemic Review of Clinical Studies about Oriental Medical Treatment of Cancer in Korea (국내에 보고된 한국 한의학의 암치료 임상연구에 대한 계통적 고찰)

  • Park, Bong-Ky;Lee, Jong-Hoon;Cho, Chong-Kwan;Shin, Hyun-Kyu;Eom, Seok-Ki;Yoo, Hwa-Seung
    • The Journal of Internal Korean Medicine
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    • v.29 no.4
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    • pp.1061-1074
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    • 2008
  • Objectives : Recently, the number of cancer patients who use complementary and alternative medicine (CAM), including oriental medicine, are increasing. Also, evidence for efficacy and safety of cancer CAM is reported continuously. This study was designed to evaluate the quality of the published papers for clinical studies about oriental medical cancer treatment in Korea. Methods : We searched for clinical research papers on the websites of the Korean oriental medical society and subsidiary academies, Korean traditional knowledge portal. Koreanstudies information service system (KISS), etc. We used the reference words 'cancer', 'malignant tumor', 'leukemia', 'lymphoma', 'multiple myeloma', 'melanoma', etc, We then chose studies that had been presented between 1991 and 2008 and analyzed them by publication year, design, cancer type, intervention, subject and journal. Results : There were 86 clinical research papers that were published between 1991 and 2008. The number of clinical studies has increased in a time-dependent manner. Case reports and case series studies account for 78% of total clinical research. Studies of lung cancer account for 17%. Studies of cancer-related symptoms of cancer patients account for 38%. Studies of Hang-Am-Dan account for 33%. Studies published in the journal of the Korean Society of Oriental Internal Medicine account for 35%. Conclusion : The clinical research papers about oriental medicine are increasing over time, but most of the studies are retrospective case reports or case series. Well-designed and prospective clinical trials would be recommended to provide more reliable evidence.

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