• Title/Summary/Keyword: center control

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Commutation Torque Ripple Reduction in Brushless DC Motor Drives Using a Single DC Current Sensor

  • Won Chang-hee;Lee Kyo-Beum;Bak Dae-Jin;Song Joong-Ho;Choy Ick;You Ji-Yoon
    • Proceedings of the KIPE Conference
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    • 2001.10a
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    • pp.409-413
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    • 2001
  • This paper presents a comprehensive study result on reducing commutation torque ripples generated in brushless dc motor drives with only a single dc-link current sensor provided. In brushless dc motor drives with only a single current sensor, the commutation torque ripple suppression that is practically effective in low speed as well as high speed regions has not been reported. A proposed commutation compensation technique based on deadbeat dc-link current controller takes a closed loop control scheme and a parameter insensitive property. The proposed control method is verified through simulations and experiments.

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Internet Web-Based Rectifier Remote Control System Using SNMP (인터넷 웹 기반 환경에서의 정류기용 원격 제어 시스템)

  • Choi, Ju-Yeop;Oh, Young-Eun;Jeon, Ho-Suk;Song, Joong-Ho;Choi, Ik
    • Proceedings of the KIPE Conference
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    • 1999.07a
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    • pp.88-92
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    • 1999
  • This paper aims at developing remote contro system to control and monitor distributed various devices through internet or information communication network. SNMP (Simple Network Management Protocol) and rectifier operated in a row are adopted for network management protocol and applied device, respectively. For controlling and monitoring distributed devices in real-time java-environment software is constructed. Also general-use interface controller between network device and applied device is proposed. Finally, seria communication such as RS-232 and RS-485 is used between controller and applied device.

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Evaluation of the Genetic Toxicity of Synthetic Chemicals (II), a Pyrethroid Insecticide, Fenpropathrin

  • Ryu, Jae-Chun;Kim, Kyung-Ran;Kim, Hyun-Joo;Ryu, Eun-Kyoung;Lee, Soo-Young;Jung, Sang-Oun;Youn, Ji-Youn;Kim, Min-Hee;Kwon, Oh-Seung
    • Archives of Pharmacal Research
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    • v.19 no.4
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    • pp.251-257
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    • 1996
  • The detection of many synthetic chemicals used in industry that may pose a genetic hazard in our environment is subject of great concern at present. In this respect, the genetic toxicity of fenpropathrin ((RS)-.alpha.-cyano-3-phenoxybenzyl-2,2,3,3-tetramethyl cyclopropane carboxylate, CAS No.:39514-41-8), a pyrethroid insecticide, was evaluated in bacterial gene mutation system, chromosome aberration in mammalian cell system and in vivo micronucleus assay with rodents. In bacterial gene mutation assay, no mutagenicity of fenpropathrin (62-$5000\mug/plate$) was observed in Salmonella typhimurium TA 98, 100, 1535 and 1537 both in the absence and in the presence of S-9 metabolic activaton system. In mammalian cell system using chinese hamster lung fibroblast, no clastogenicity of fenpropathrin was also observed both in the absence and in the presence of metabolic activation system in the concentration range of $7-28\mug/ml$. And also, in vivo micronucleus assay using mouse bone marrow cells, fenpropathrin also revealed no mutagenic potential in the dose range of 27-105 mg/kg body weight of fenpropathrin (i.p.). Consequently, no mutagenic potential of fenpropathrin was observed in vitro bacterial, mammalian mutagenicity systems and in vivo micronucleus assay in the dose ranges used in this experiment.

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Enzymatic Synthesis of Puerarin Glucosides Using Leuconostoc Dextransucrase

  • Ko, Jin-A;Ryu, Young Bae;Park, Tae-Soon;Jeong, Hyung Jae;Kim, Jang-Hoon;Park, Su-Jin;Kim, Joong-Su;Kim, Doman;Kim, Young-Min;Lee, Woo Song
    • Journal of Microbiology and Biotechnology
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    • v.22 no.9
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    • pp.1224-1229
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    • 2012
  • Puerarin (P), an isoflavone derived from kudzu roots, has strong biological activities, but its bioavailability is often limited by its low water solubility. To increase its solubility, P was glucosylated by three dextransucrases from Leuconostoc or Streptococcus species. Leuconostoc lactis EG001 dextransucrase exhibited the highest productivity of puerarin glucosides (P-Gs) among the three tested enzymes, and it primarily produced two P-Gs with a 53% yield. Their structures were identified as ${\alpha}$-$_D$-glucosyl-($1{\rightarrow}6$)-P (P-G) by using LC-MS or $^1H$- or $^{13}C$-NMR spectroscopies and ${\alpha}$-$_D$-isomaltosyl-($1{\rightarrow}6$)-P (P-IG2) by using specific enzymatic hydrolysis, and their solubilities were 15- and 202-fold higher than that of P, respectively. P-G and P-IG2 are easily applicable in the food and pharmaceutical industries as alternative functional materials.

Factors Related to Smoking Recurrence within Six-months Smoking Cessation among Employees in Enterprises with Smaller than 300 Workers (300인 미만 사업장근로자의 6개월 이내 재흡연 관련요인)

  • Jin, Byung Jun;Kim, Chul-Woung;Lee, Seung Eun;Im, Hyo-Bin;Lee, Tae-Yong
    • Research in Community and Public Health Nursing
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    • v.32 no.1
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    • pp.107-115
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    • 2021
  • Purpose: The purpose of this study is to identify factors associated with smoking relapse within six months after quit attempts among workers in small and medium-sized enterprises in South Korea. Methods: The analysis was conducted for a total of 194 people who attempted to quit smoking by applying for a smoking cessation support service at the Regional Tobacco Control Center. The data used in the study were extracted from the Smoking Cessation Service Integrated Information System. Kaplan-Meier estimator and Cox proportional hazards regression model were used to identify variables associated with smoking relapse within six months' time period. Results: Smoking relapse rate within six months was 66.0%, and variables associated with relapse included the cases such as carbon monoxide (CO) at the time of registration (HR: 2.15, 95% CI: 1.10~4.22 for CO ≥20 ppm or more vs.CO <10 ppm), the average number of cigarettes smoked per day (HR: 1.04, 95% CI: 1.00~1.07), and the number of counseling(HR: 0.60, 95% CI: 0.54~0.67). Conclusion: Smoking characteristics and counseling showed one of the strongest correlations with relapse within six months. This implies that it is necessary to understand the smoking characteristics and patterns of workers and to provide continuous smoking cessation counseling tailored to individual characteristics for effective smoking relapse prevention.

A Case of Plasmodium ovale wallikeri Infection in a Chinese Worker Returning from West Africa

  • Li, Yuchun;Wang, Guangze;Sun, Dingwei;Meng, Feng;Lin, Shigan;Hu, Ximin;Wang, Shanqing
    • Parasites, Hosts and Diseases
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    • v.51 no.5
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    • pp.557-562
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    • 2013
  • In contrast to the gradual reduction in the number of locally transmitted malaria cases in China, the number of imported malaria cases has been increasing since 2008. Here, we report a case of a 39-year-old Chinese man who acquired Plasmodium ovale wallikeri infection while staying in Ghana, West Africa for 6 months in 2012. Microscopic examinations of Giemsa-stained thin and thick blood smears indicated Plasmodium vivax infection. However, the results of rapid diagnostic tests, which were conducted 3 times, were not in agreement with P. vivax. To further check the diagnosis, standard PCR analysis of the small-subunit rRNA gene was conducted, based on which a phylogeny tree was constructed. The results of gene sequencing indicated that this malaria is a variant of P. ovale (P. ovale wallikeri). The infection in this patient was not a new infection, but a relapse of the infection from the one that he had contracted in West Africa.

A Study on Design of TMR Control System for Steam Turbine (터빈 감시제어용 삼중화 제어시스템 설계에 관한 연구)

  • Ahn, Jong-Bo;Kim, Kook-Hun;Kim, Seog-Joo;Kim, Chun-Kyong;Kim, Jong-Moon
    • Proceedings of the KIEE Conference
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    • 2000.11d
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    • pp.663-665
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    • 2000
  • For the control system of thermal turbine in fuel and nuclear power plant, as high reliability and availability are required, redundant control system is generally applied. This paper presents the configuration and design of such a redundant control system that can be suitable for control and monitoring of the turbine. System components such as I/O system, communication networks, voting system are designed, and especially the new intelligent voter using serial communication are proposed. The characteristics of the implemented control system is independence of the control, protection and monitoring functions, and discrimination of the redundancies, and high availability. The control functions such as speed control, load control, valve control and protective functions such as overspeed and PLU are designed in detail.

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Prevalence of Cystic Echinococcosis in Slaughtered Sheep as an Indicator to Assess Control Progress in Emin County, Xinjiang, China

  • Yang, Shijie;Wu, Weiping;Tian, Tian;Zhao, Jiangshan;Chen, Kang;Wang, Qinyan;Feng, Zheng
    • Parasites, Hosts and Diseases
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    • v.53 no.3
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    • pp.355-359
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    • 2015
  • Hydatid disease imposing serious threat on human health and great loss in live-stock pastoralism remains a major public health problem in western China. To assess and monitor the effect of control program on transmission dynamics, we used the prevalence of cystic echinococcosis in slaughtered sheep at slaughterhouse as an indicator during the period of 2007 to 2013 in Emin County, Xinjiang Uygur Autonomous Region, China. The results showed a significant decline trend of prevalence in all age groups during the 7 years when the control program was implemented; particularly, the rate was reduced by 72% after first 3 years. Among the sheep slaughtered, the age distribution evidenced that the prevalence increased significantly as the sheep grew older. The baseline data indicated that the rate was 4.5% at the age <1, 6.7% at age 2~, and reached to the highest 17.9% at age ${\geq}4$ years. Earlier response to the intervention pressure was seen in the sheep at the younger age. Significant decline started from 2008 at the age <1, from 2009 at age of 1~, 2010 at 2~ to 3~, and the latest, in 2012 at age ${\geq}4$. This study demonstrated that the prevalence of cystic echinococcosis in slaughtered sheep may be used as an indicator to assess and monitor the transmission status during and after control program providing information for betterment of performance to sustain control strength.

Genomic analysis of Sheldrake origin goose hemorrhagic polyomavirus, China

  • Wan, Chunhe;Chen, Cuiteng;Cheng, Longfei;Liu, Rongchang;Fu, Guanghua;Shi, Shaohua;Chen, Hongmei;Fu, Qiuling;Huang, Yu
    • Journal of Veterinary Science
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    • v.19 no.6
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    • pp.782-787
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    • 2018
  • Goose hemorrhagic polyomavirus (GHPV) is not a naturally occurring infection in geese in China; however, GHPV infection has been identified in Pekin ducks, a domestic duck species. Herein, we investigated the prevalence of GHPV in five domestic duck species (Liancheng white ducks, Putian black ducks, Shan Sheldrake, Shaoxing duck, and Jinyun Sheldrake) in China. We determined that the Jinyun Sheldrake duck species could be infected by GHPV with no clinical signs, whereas no infection was identified in the other four duck species. We sequenced the complete genome of the Jinyun Sheldrake origin GHPV. Genomic data comparison suggested that GHPVs share a conserved genomic structure, regardless of the host (duck or geese) or region (Asia or Europe). Jinyun Sheldrake origin GHPV genomic characterization and epidemiological studies will increase our understanding of potential heterologous reservoirs of GHPV.

The Molecular Characterization of Serogroup C Neisseria meningitidis Strains Circulating in Beijing

  • Zhang, Tie-Gang;He, Jing-Guo;He, Xiong;Chen, Li-Juan;Shao, Zhu-Jun;Sun, Mei-Ping
    • Journal of Microbiology
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    • v.44 no.6
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    • pp.685-688
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    • 2006
  • The aim of this study was to characterize the molecular features of serogroup C Neisseria meningitidis strains circulating in Beijing, China. Twenty out of 23 strains belonged to ST 4821. The causative serosubtype for meningococcal meningitis was P1.12-1,16-8. All of the strains expressed class 3 PorB protein. Among the five pulsed-field gel electrophoresis patterns observed, pattern III predominated.