• Title/Summary/Keyword: long-duration

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

  • Kim, S.S.;Choi, I.S.;Cho, H.G.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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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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Properties & Performance Evaluation of Disconnector for Surge Arrester (피뢰기용 단로기의 특성 및 성능 평가)

  • Kim, Seok-Sou;Choi, Ike-Sun;Jeong, Nak-Heon;Park, Tae-Gon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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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
    • Cross-Cultural Studies
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    • v.24
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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.

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

  • 이동협
    • Journal of Chest Surgery
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    • v.18 no.4
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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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Clinical Observation of Esophageal Cancer (식도암의 임상적 고찰)

  • 정영환
    • Journal of Chest Surgery
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    • v.5 no.2
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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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Development of Long Term Flow Duration Curves for the Management of Total Maximum Daily Loads - in the Nakdong River Basin - (수질오염총량관리 단위유역 장기유황곡선 구축 -낙동강수계를 대상으로-)

  • Kim, Gyeong hoon;Kwon, Heon gak;Ahn, Jung min;Kim, Sanghun;Im, Tae hyo;Shin, Dong seok;Jung, Kang-Young
    • Journal of Environmental Science International
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    • v.26 no.8
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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.

A Study on Correlation between Anti-Obesity Effect and Safety According to Medication Period of Korean Medicine in Overweight and Obese Patients: A Retrospective Analysis (과체중 및 비만 환자의 복약기간에 따른 치료효과 및 안전성의 상관관계: 후향적 분석)

  • Hyeon Choi;Jung-Hun Nam;Hyuk-Jae Lee;Ki-Seong Seo
    • Journal of Korean Medicine for Obesity Research
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    • v.24 no.1
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    • pp.76-86
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    • 2024
  • Objectives: This retrospective study attempted to determine whether the treatment effect improves as the longer the medication for obese patients, also, analyzed whether the long medication increases the burden on liver function. Methods: The subjects were 278 overweight and obese female patients who took the herbal medicine Jibangsayak (JBSY) for more than 15 days. The correlation between the duration of medication and the treatment effect was confirmed, and the correlation with the safety was also analyzed. Results: JBSY significantly reduced all obesity-related measures after treatment. All these valuables before treatment were not factors in determining the duration of medication. As the duration increased, the body mass index (BMI) improvement decreased and lean body and muscle mass increased. As the duration was closer to 60 days, BMI improvement increased, and in more than 90 days group, the BMI and body fat percentage improvement stagnated as the duration longer. Aspartate aminotransferase (AST), alanine aminotransferase, and gamma-glutamyl transferase decreased after treatment. Additionally, AST decreased as the duration increased. Conclusions: This result suggests that not only the high obesity-related measures at first visit not lengthen the duration of JBSY medication. And liver function levels did not worsen as the duration increased. This result is different from the general perception that the longer the duration of medication, the greater the burden on patient's drug metabolism. However, the fact that other factors that could affect liver function could not be excluded and that kidney function evaluation should have been performed simultaneously are limitations of this study and require more detailed research in the future.

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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    • v.9 no.1
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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.

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

  • Kim, Dae Geun;Jeong, Jae Ung;Park, Jae Hyun;Park, Chang Geun
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.3
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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.

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

  • Lee, Hoon-Young;Jung, Kee-Taig;Shine, Eun-Kyu;Han, Yong-Jun
    • Korea Journal of Hospital Management
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    • v.13 no.3
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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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