• Title/Summary/Keyword: current status of resistance

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A Development of Ethernet-Based Remote Diagnosis System for DC Voltage Smoothing Capacitor using DSP (DSP를 적용한 전력용 DC 평활 커패시터의 이더넷 원격 고장진단시스템 개발)

  • Shon, Jin-Geun
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.60 no.2
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    • pp.94-98
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    • 2011
  • Electrolytic power capacitors today form essential components for virtually any power electronic system such as DC/DC converter or UPS. Frequently, electrolytic capacitors for DC link voltage smoothing are the key components which determine the life cycle of the whole unit and often are responsible for converter breakdown failures. In this paper, ethernet-based remote diagnosis system for DC voltage smoothing capacitor using DSP control board is developed. To estimate the status of the capacitor, the equivalent series resistor(ESR) of the component has to be determined. The ESR detection scheme is based on the determination of the capacitor ripple power losses calculated from DC link voltage/current measurement. Experimental results show the veridity and reliability of the proposed ethernet-based remote on-line capacitor diagnosis system.

A Study on Ground Fault Detecting System for DC Voltage Line in the Electric Power Plant (발전소 직류전압 전선로 접지검출시스템에 관한 연구)

  • Lee, H.K.;Kim, N.H.;Park, C.H.;Kim, T.S.
    • Proceedings of the KIEE Conference
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    • 1995.07b
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    • pp.754-757
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    • 1995
  • This system can detect a ground fault point or a bad insulated line by measuring a power plant DC feeder insulation resistance at the uninterruptible power status. And when the power plant DC feeder with low frequency AC signal has a ground fault, this measuring system can keep recording of its ground fault current and phase checked by Z.C.T. Therefore the power plant could protect a unexpected service interruption.

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Current Status of Interval of Heparin Flushing for Maintenance of an Implanted Port in Solid Tumor Patients (고형암 환자의 삽입형 포트 개방성 유지를 위한 헤파린 관류 주기 현황)

  • Kim, Hye Kyung;Choi, So Eun;Lee, Jung Hoon;We, Eun Sook;Joh, Hye Jin;Kim, Kwang Sung
    • Journal of Korean Biological Nursing Science
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    • v.16 no.3
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    • pp.251-257
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    • 2014
  • Purpose: Little is known about appropriate interval periods between the heparin flushing of implanted ports after completion of chemotherapy. The purpose of this study was to describe the current status of interval of heparin flushing for maintenance of an implanted port in solid tumor patients. Methods: We performed a retrospective review of all patients who had undergone implanted port removal in 2012 at the Seoul St. Mary's Hospital. The subjects were 90 patients who, after completion of chemotherapy, retained their ports for extended periods of time. Results: The mean number of flushes of heparin was 4. Compliance with visits for implanted port maintenance varied with the individual, and the mean accession times were in the range between 13 days and 243 days. The overall mean time between flushes was 66 days. One patient showed resistance during flushing. Conclusion: Our results demonstrate that extending the flushing interval to a maximum of 8 weeks remains medically safe. Less frequent heparin flushing of an implanted port decreases medical expenditure and the workload of medical professionals; it also improves the patient's satisfaction.

Current Methods of Circulating Tumor Cell Detection (순환종양세포 검출 기술)

  • Lim, Minji;Cho, Yoon-Kyoung
    • The Korean journal of helicobacter and upper gastrointestinal research
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    • v.18 no.3
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    • pp.157-161
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    • 2018
  • Liquid biopsy, the analysis of circulating biomarkers from peripheral blood, such as circulating tumor cells (CTCs) and circulating tumor DNA, and exosomes, offers a less invasive, new source of cancer-derived materials that may reflect the status of the disease better and thereby contribute to personalized treatment. Recent advances in microfluidics and molecular analysis technologies have resulted in greatly improved CTC enumeration and detection. In this article, we review commercially available technologies used to isolate CTCs from peripheral blood, including immunoaffinity and label-free, physical property-based isolation methods. Although enormous technological progress has been made, especially within the last decade, only a few CTC detection methods have been approved for routine clinical use. Here, we provide an overview of the current CTC isolation methods and examples of their potential application for early diagnosis, prognosis, treatment monitoring, and prediction of resistance to cancer therapy. Furthermore, the challenges that remain to be addressed before such tools are implemented for routine use in clinical settings are discussed.

A Study on Development and Diagnosis Factors of On-Line DC Leakage Current System for Junctions of High-Voltage Cables in Operation at Thermoelectric Power Station (화력 발전소 고전압 케이블 접속재의 On-Line 직류 누설 전류 시스템 개발과 진단 Factor에 관한 연구)

  • Park, Sung-Hee;Um, Kee-Hong
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.18 no.6
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    • pp.187-193
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    • 2018
  • There has been a gradual increase in the demand for the electric power in Korea. In order to meet the demand, power station should have technical functions with increased effectiveness. When accident happens in electric machinery at power stations, huge amount of economic losses and mulfunction of equipments occur. One of the accidents is a deteriorated cables operating power stations. In order to prevent cable accident in advance, we should monitor the insulation status of the cable. Cable accidents are resulting from the junctions. We have developed and installed a device in order to identify the status of junction part of power cable at Korea Western Power Co., Ltd.. We performed an accurate diagnosis for the stable utilization of junctions where the accidents occurs most frequently, and to increase the reliability. In this paper, we present the concepts of our device and the method of monitoring diagnosis for the stable use of junctions at cables predicting the life time of cables by analyzing the data obtained by the device. We also present the hardware aspect of the device we have developed.

Properties of Silicone and its Suitability as a Synthetic Leather Coating Agent (실리콘의 특성 이해와 합성피혁 코팅제로서의 적합성)

  • Suhong Kim;Doohyun Baik
    • Textile Coloration and Finishing
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    • v.35 no.1
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    • pp.42-65
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    • 2023
  • Leather is widely used in human lives and many industries, and the market size continues to grow. In terms of quality and durability, natural leather is still being used as the most luxurious product. And synthetic leather, made of polyvinyl chloride (PVC) and polyurethane (PU), were developed and being widely have been used as alternative materials for natural leather. Processes, properties and issues of these leather were reviewed. Then silicone leather was reviewed why they can be good candidates for leather. Properties of general silicone polymers and silicone rubber coating agents were reviewed such as eco-friendliness, human-friendliness, stain resistances, resistance to uv light and ozone, heat stability and so on. Papers and patents related to silicone leather were studied to understand current status of development and commercialization of silicone leather. Finally direction of development was described how to improve deficient performances of current silicone leather, such as formulation of silicone, combination with organic materials and manufacturing processes.

Current status and prospects to identify mutations responsible for mutant phenotypes by using NGS technology (NGS 기술 활용 돌연변이체 해석 및 연구현황)

  • Jung, Yu Jin;Ryu, Ho Jin;Cho, Yong-Gu;Kang, Kwon Kyoo
    • Journal of Plant Biotechnology
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    • v.43 no.4
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    • pp.411-416
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    • 2016
  • Next-generation sequencing allows the identification of mutations responsible for mutant phenotypes by whole-genome resequencing and alignment to a reference genome. However, when the resequenced cultivar/line displays significant structural variation from the reference genome, mutations in the genome regions absent in the reference cannot be identified by simple alignment. In this review, we report the current status and prospects in identification of genes in mutant phenotypes, by using the methods MutMap, MutMap-Gap, and MutMap+. These methods delineate a candidate region harboring a mutation of interest, followed by de novo assembly, alignment, and identification of the mutation within genome gaps. These methods are likely to prove useful for cloning genes that exhibit significant structural variations, such as disease resistance genes of the nucleotide-binding site-leucine rich repeat (NBS-LRR) class.

Current Status and Consideration of Breeding Research on Olive Flounder in Korea (우리나라 넙치 육종연구에 관한 현황 및 고찰)

  • Jong Won Park;Jeong Ho Lee;Hyun Chul Kim
    • Journal of Practical Agriculture & Fisheries Research
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    • v.25 no.3
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    • pp.35-46
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    • 2023
  • It was in the 1982 that artificial seed production research for olive flounder (Paralichthys olivaceus) farming was first conducted in Korea (Currently, National Institute of Fisheries Science, Fish Breeding Research Center). In 1985, fertilized eggs were obtained from natural olive flounder adapted to land tanks, and artificial seed production technology was established and fertilized eggs were distributed. In the late 1980s, halibut aquaculture began to prosper in land-based tank farming in Jeju Island and Busan's Gijang region, where water temperatures are relatively high in winter. Currently, aquaculture is being carried out all over the country, centering on Jeju Island and Wando, Jeollanam-do. However, olive flounder farming, which started with a small group in the 1980s, reduced genetic diversity through inbreeding over generations, resulting in side effects such as slow growth, reduced resistance to disease and environmental conditions. In order to solve these genetic problems of farmed olive flounder in Korea, the Fish Breeding Research Center of the National Institute of Fisheries Science introduced a wild-caught parent fish group to the existing aquaculture group from 2003 to 2004. Genetic diversity was secured and KingNupchi with fast growth and improved body shape was developed. In this study, the current status of breeding technology development of olive flounder, a major aquaculture breed in Korea, is reviewed and future research directions are suggested.

Current Status of Nickel Smelting Technology (니켈 제련기술의 현황)

  • Sohn, Ho-Sang
    • Resources Recycling
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    • v.30 no.2
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    • pp.3-13
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    • 2021
  • Nickel is widely used due to its excellent toughness, malleability and enhanced corrosion resistance. Therefore, nickel is indispensable in our daily lives, and it is widely used in basic to advanced applications such as stainless steel, super alloys and electronic devices. Recently, nickel has been widely used as the major material in secondary batteries and capacitors. The use of nickel continues to rise and has increased from 800 thousand tonnes per year worldwide in the 1970s to about 2 million tonnes in the 2010s. However, nickel is a representative rare metal and ranks 23rd among the abundant elements in the earth's crust. This study reviews the current status of the nickel smelting processes as well as the trend in production amount and use. Nickel is extracted by a wide variety of smelting methods depending on the type of ore. These smelting methods are essential for the development of new recycling processes that can extract nickel from secondary nickel resources.

Report on the 54th annual meeting of the weed science society of Japan (일본잡초학회에서 본 일본의 잡초연구 동향)

  • Hwang, Jae-Bok;Kim, Kyung-Hyun
    • Korean Journal of Agricultural Science
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    • v.42 no.4
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    • pp.335-339
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    • 2015
  • This paper reviews current status of weed science in Japanese regional agricultural systems based on the 54th Annual Meeting of the Weed Science Society of Japan. About 300 researchers from 5 countries including Korea participated in the Conference and presented 100 papers in research areas. This congress has an purpose to discuss new troubles, findings and results of weed science. Weed science faces big challenges such as increase in herbicide-resistant weeds, gene-flow from transgenic crops, and invasive weeds. Major research topics were invasive weeds and their ecology, allelopathy, weed management in paddy field, weed management in field crops, and herbicide resistance. Weed control and herbicide resistance management in paddy field were a main object of research. To prevent the increase of problematic weeds and to overcome food crisis, the importance of weed-related researches has been raised. Therefore it is expected that various weed management systems and control of herbicide resistant weeds should be studied continuously in the weed science.