• Title/Summary/Keyword: Long-duration

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송전급 피뢰기의 구조와 성능평가 (Contruction and Performance Evaluation of the Surge Arrester for Transmission Class)

  • 김석수;최익순;조한구
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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    • pp.890-893
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    • 2002
  • Since 1970s, varistors using metal-oxide resistors have been applied to Gapless surge arresters for power system. In the paper, the structure of metal-oxide surge arresters without gaps for 362kV GIS which is developed the first in korea has been introduced. And the main evaluation items for the metal-oxide resistors which are reference voltage test, residual voltage test, long duration current impulse withstand test and operating duty test is tested and evaluated.

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피뢰기용 단로기의 특성 및 성능 평가 (Properties & Performance Evaluation of Disconnector for Surge Arrester)

  • 김석수;최익순;정낙헌;박태곤
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.546-547
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    • 2005
  • This study aims to evaluate the properties and the performance of the newly designed disconnector for surge arrester. This disconnector was verified with the performance in long-duration current impulse test and high current impulse test. And time-current characteristic test was done at 20A, 200A and 800A(3points) for simulating the internal fault condition of the arrester. The results of this test was very good. Consequently, the newly designed disconnector was, evaluated that it is possible to be used for surge arrester in distribution line system.

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Role of amplitude and pitch in the perception of Japanese stop length contrasts

  • Idemaru, Kaori
    • 비교문화연구
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    • 제24권
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    • pp.112-119
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    • 2011
  • This study presents experiments which examined the role of amplitude and fundamental frequency (f0) in the phonetic perception of short versus long stop length contrasts in Japanese (e.g., [t] vs. [tt]). Stop length contrasts are normally characterized by differences in the duration of stop closures. However, closure duration can be unreliable as a perceptual cue when one considers variability in the rate at which people speak. Acoustically, the amplitude and f0 of the vowel following stop consonants are known to covary with the length distinction of stops in Japanese. Given this fact, the current study examined amplitude and f0 as potential secondary cues to the distinction. The results indicate that even though both amplitude and f0 are robust correlates, Japanese listeners do not use these cues in categorizing short versus long stops.

근무력증의 외과적 치료 (Role of Thymectomy for the Management of Myasthenia Gravis)

  • 이동협
    • Journal of Chest Surgery
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    • 제18권4호
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    • pp.859-866
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    • 1985
  • The characteristic features of myasthenia gravis, which are weakness of voluntary muscle and easy fatigability, result from defective neuromuscular transmission caused by an autoimmune response to acetylcholine receptor. Recently, we performed two cases of thymectomy for the treatment of myasthenia gravis, one was 50 year old man who had malignant thymoma and the other was 19 year old girl who had benign thymic hyperplasia. The former had long duration of symptoms, and showed poor postoperative result. The latter had short duration of symptoms, and showed complete remission. Herewith, we suggest that early thymectomy can give the clinical assets for myasthenia gravis. So we report these two experiences with review of literatures.

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식도암의 임상적 고찰 (Clinical Observation of Esophageal Cancer)

  • 정영환
    • Journal of Chest Surgery
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    • 제5권2호
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    • pp.159-164
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    • 1972
  • Clinical observation is made in 29 cases of patients with esophageal cancer at Department of Chest Surgery in Chunnam University Hospital. 1] The prevalent age of male patient is fifth decade and of female is fourth and fifth decade. The average age of patient is 54 years old. 2] Duration of the disease before admission is relatively long, the duration within 7-9 months is 35% of all patients. 3] On the majority of patients, typical symptoms of esophageal cancer were manifested. 4] Operation was performed on 58% of all patients, in 23% curative and in 35% palliative resection was done.

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수질오염총량관리 단위유역 장기유황곡선 구축 -낙동강수계를 대상으로- (Development of Long Term Flow Duration Curves for the Management of Total Maximum Daily Loads - in the Nakdong River Basin -)

  • 김경훈;권헌각;안정민;김상훈;임태효;신동석;정강영
    • 한국환경과학회지
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    • 제26권8호
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    • pp.939-953
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    • 2017
  • For the development of flow duration curves for the management of 41 Total Maximum Daily Load (TMDL) units of the Nakdong River basin, first, an equation for estimating daily flow rates as well as the level of correlation (correlation and determination coefficients) was extrapolated through regression analysis of discrete (Ministry of Environment) and continuous (Ministry of Land, Infrastructure and Transportation) measurement data. The equation derived from the analysis was used to estimate daily flow rates in order to develop flow duration curves for each TMDL unit. By using the equation, the annual flow duration curves and flow curves, for the entire period and for each TMDL unit of the basin, were developed to be demonstrated in this research. Standard flow rates (abundant-, ordinary-, low- and drought flows) for major flow duration periods were calculated based on the annual flow duration curves. Then, the flow rates, based on percentile ranks of exceedance probabilities (5, 25, 50, 75, and 95%), were calculated according to the flow duration curves for the entire period and are suggested in this research. These results can be used for feasibility assessment of the set values of primary and secondary standard flow rates for each river system, which are derived from complicated models. In addition, they will also be useful for the process of implementing TMDL management, including evaluation of the target level of water purity based on load duration curves.

Studies on Long-term Preservation of Eggs of Indian Tropical Multivoltine Silkworm (Bombyx mori L.) Genetic Resources

  • Kumaresan, P.;Thangavelu, K.;Sinha, R.K.
    • International Journal of Industrial Entomology and Biomaterials
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    • 제9권1호
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    • pp.79-87
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    • 2004
  • The silkworm rearing and growth parameters of 63 multivoltine silkworm accessions under extended period of egg preservation at 5$^{\circ}C$ from 30 days to 45 days were studied. The results indicate that, nine accessions did not respond to extended period of egg preservation at low temperature and the remaining 54 accessions responded to the treatment and three rearings were conducted for comparision with the control; to estimate the effect of prolonged egg preservation at low temperature. The non-parametric tests statistics (Wilcoxon tests) was adopted for comparing the mean performance of treated batches (45 days) over the control (30 days). Highly significant variability was found among the accessions for all the parameters under study. The genetically controlled morphological characters were not altered in the treated batches, which were found to be on par with that of control. However, the total larval duration varied significantly over the control in 51 accessions. Similarly, the fifth age larval duration of 27 accessions showed decreasing trend compared to control. Altogether 41 accessions were found to be tolerant to long-term cold preservation upto 45 days, without showing any significant variation for morphological as well as essential quantitative traits. These accessions may be recommended for long-term egg preservation schedule up to 45 days, which will reduce the cost of conservation of these silkworm germplasm.

적설 및 융설의 영향을 고려한 장기유출 모의 (Long-Term Runoff Simulation in Consideration of Snow Pack and Snow Melt)

  • 김대근;정재웅;박재현;박창근
    • 상하수도학회지
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    • 제21권3호
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    • pp.265-272
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    • 2007
  • This study uses the SWAT model to analyze the characteristics of long-term runoff at the Ssang-cheon Basin located in the city of Sokcho, which is located in the province of Gangwon. The study considers the effect of snow packing and snow melting in a runoff simulation. In this simulation, the study examines the need to introduce a snow pack and snow melt model to evaluate the water resources of the mountainous region of the Gangwon province. The findings of this study indicate that the runoff hydrograph that was produced approximates the true measured flow when the effect of the snow pack and snow melt are considered, compared to when they are not factored in. The analysis of the flow duration curve indicates that the stream flow largely increases when the effect of the snow pack and snow melt are considered. The wet stream flow was shown to increase by nearly 3% due to the melting effect, while the normal stream flow, low stream flow and drought stream flow were shown to increase by slightly more than 10%. Specifically, it was found that as the stream flow decreases, the effect of the snow pack and snow melt on the stream flow increases.

입원기간에 따른 의료서비스 품질요인이 고객만족에 미치는 영향에 관한 연구 (The Impact of Health Service Quality Factors on Patient's Satisfaction According to Duration of Hospitalization)

  • 이훈영;정기택;신은규;한용준
    • 한국병원경영학회지
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    • 제13권3호
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    • pp.44-68
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    • 2008
  • The purpose of this study is to identify which factors of medical service quality were considered important by patients based on survey on eight hospitals located in Seoul. We analyzed the difference in impact of health service quality factors between the two groups with short and long inpatient days. In addition, we analyzed which service factors affected the customer satisfaction more differently across the inpatient groups. We found that patient satisfaction was not different between the two groups with short and long inpatient days. But the two groups showed different priority orders of medical service factors that affect patient satisfaction. In the group with long inpatient days, the order of medical service factors are cleanness, speciality, process. In the group with short stay, important factors are speciality, cleanness and convenience of facilities. These findings imply that hospitals should set up different marketing strategies across the different inpatients groups.

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Long-Term Outcomes of Placement of a Single Transverse Stent through the Anterior Communicating Artery via the Nondominant A1 in Coil Embolization of Wide-Necked Anterior Communicating Artery Aneurysms

  • Ban, Seung Pil;Kwon, O-Ki;Kim, Young Deok
    • Journal of Korean Neurosurgical Society
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    • 제65권1호
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    • pp.40-48
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    • 2022
  • Objective : Placement of a single transverse stent via the nondominant A1 across the anterior communicating artery (AComA) into the contralateral A2 can provide sufficient neck coverage for wide-necked bifurcation AComA aneurysms. The authors described the feasibility, safety and long-term outcomes of this technique. Methods : Between January 2015 and February 2018, placement of a single transverse stent via the nondominant A1 was attempted in 17 wide-necked bifurcation AComA aneurysms. The authors reviewed the medical records and radiological studies. Results : The technical success rate was 94.1% (16/17). Periprocedural thromboembolic complications occurred in one patient (6.3%) without permanent neurological deficits. The mean clinical follow-up duration was 39.9±9.8 months. No deaths or delayed thromboembolic complications occurred. The mean angiographic follow-up duration was 38.9±9.8 months. The immediate and final follow-up complete occlusion rates were 87.4 and 93.7%, respectively. There was no recanalization during the follow-up period. Conclusion : Placement of a single transverse stent via the nondominant A1 across the AComA into the contralateral A2 is a feasible and relatively safe endovascular technique for the treatment of wide-necked bifurcation AComA aneurysms, with good long-term occlusion rates and a reasonable complication rate, if only the nondominant A1 is applicable.