• 제목/요약/키워드: Standard variation

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주 40시간 근무제의 도입이 근로시간, 임금 및 고용에 미치는 영향 (The Impacts of the 40 Hour Work Week Standard on Actual Working Hours, Wages and Employment)

  • 김형락;이정민
    • 노동경제논집
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    • 제35권3호
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    • pp.83-100
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    • 2012
  • 본 연구는 2004년부터 점진적으로 실시된 주40시간 근무제, 이른바 '주5일 근무제'의 도입이 근로시간, 임금 및 고용에 미친 효과를 "고용형태별근로실태조사" 원자료를 이용하여 추정하였다. 법정 근로시간 단축이 연도별 산업별 및 사업체 규모별로 단계적으로 적용되었던 점에 착안하여 삼중차감 모형을 사용하였다. 희귀분석 결과, 주 40시간 근무제의 도입으로 실제 근로 시간은 약 43분 단축되었고, 시간당 임금은 약 6.6% 상승한 것으로 나타났으나 신규 고용은 약 2.3%포인트 하락시킨 것으로 나타났다.

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정류방식에 따른 장치의 정확도와 출력 파형의 비교 (Comparison of Accuracy and Output Waveform of Devices According to Rectification Method)

  • 이인자
    • 대한방사선기술학회지:방사선기술과학
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    • 제41권6호
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    • pp.603-610
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    • 2018
  • This study examined the following: accuracy of the exposure conditions in the inverter device and three-phase device; output waveform over the exposure conditions; and average and standard deviation of the output waveform. After assessing whether the dose corresponding to the theoretical dose was presented, the following conclusions were obtained: 1. The accuracy of the tube voltage(kVp) and tube current(mA) exposure time(sec) was within the tolerable level prescribed in Korea's Safety Management Standards. In the error, Inverter device was large the tube voltage and exposure time, the three-phase device was large the tube current. 2. In terms of the output waveform of the exposure conditions and the average and standard deviation of the output waveform, the higher tube voltage and larger tube current resulted in greater standard deviation in pulsation. Moreover, the standard deviation of pulsation was shown to be greater in the inverter device than the three-phase device; there was also greater standard deviation in the inverter device considering the exposure time. 3. Regarding the exposure conditions over the output dose, all linearity showed the coefficient of variation which had an allowable limit of error within 0.05. Although the output dose ratio for the inverter device was 1.00~1.10 times no difference that of the three-phase device, there was almost no difference in dose ratio between the tube currents.

Stabilization and solidification of tailings from a traditional gold mine using Portland cement

  • Rachman, Ranno Marlany;Bahri, Ayi Syaeful;Trihadiningrum, Yulinah
    • Environmental Engineering Research
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    • 제23권2호
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    • pp.189-194
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    • 2018
  • The traditional gold mining in Kulon Progo district, Special Region of Yogyakarta Province produced tailings containing mercury (Hg) from the gold amalgamation process. Mercury accumulated in tailings has 164.19 mg/kg - 383.21 mg/kg in total concentration. Stabilization/solidification (S/S) is one of the remediation technologies to reduce waste pollution. Portland cement is one of the additive materials in S/S that effective encapsulates heavy metal waste. The aim of this research is to know the optimum composition of tailings mixture with Portland cement in S/S process. This research used variation of tailings composition. Variation of Portland cement composition with tailing are 100:0, 90:10, 80:20, 70:30, 60:40, 50:50, 40:60, 30:70, 20:80 and 10:90. The result of this study found that the optimum composition of Portland cement: tailings was 10:90, with compression test of $257ton/m^2$ and TCLP test was 0.0069 mg/L. The compression test results were in accordance to US EPA Standard quality of $35ton/m^2$. TCLP test results meet the standard of Indonesian Government Regulation No. 101 Year 2014 of 0.05 mg/L.

한국프로야구에서의 피타고라스 정리의 정확도 측정 (Measuring the accuracy of the Pythagorean theorem in Korean pro-baseball)

  • 이장택
    • Journal of the Korean Data and Information Science Society
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    • 제26권3호
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    • pp.653-659
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    • 2015
  • 야구의 피타고라스 정리는 야구의 승률을 추정하는 방법으로 오랜 기간 동안 타당성이 입증되고 또 활용되고 있다. 본 연구에서는 2005년부터 2014년 사이의 한국프로야구 팀대 팀 전체기록을 이용하여 실제승률과 피타고라스 정리에 의해 추정된 기대승률의 차이가 발생하는 원인을 회귀모형을 이용하여 살펴보았다. 기대승률과 실제승률의 차이가 큰 경우는 득점과 실점의 분포가 특이하다는 가정아래에서 종속변수는 실제승률과 기대승률의 차이, 독립변수로는 게임당 득점 및 실점의 평균, 표준편차, 변동계수를 각각 이용하였다. 그 결과 실제승률과 기대승률의 차이에는 게임당 실점의 표준편차와 변동계수가 영향을 미치며 게임당 득점의 영향은 없는 것으로 나타났다.

PV모듈 발전성능 비교시험과 계측편차 요인 분석 (Analysis of Comparison Test and Measurement Error Factor for I - V Performance of Photovoltaic Module)

  • 강기환;김경수;유권종;안형근;한득영
    • 한국태양에너지학회 논문집
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    • 제29권2호
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    • pp.70-75
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    • 2009
  • In this experiment, we did sampling 6 kinds of photovoltaic modules and analyzed the discrepancy of measurement results between l laboratory and 4 PV makers to have performance repeatability at Standard Test Condition(STC) condition. From the KIER's results, Korea's standard test laboratory, other laboratory showed -10% measurement variation. The causes came from correction of reference cell, test condition and the state of skill. Form the comparison test, we analyzed the problems. But three PV maker reduced measurement variation, other one PV maker and one test laboratory didn't improve the problems of correction of reference cell, test condition and the state of skill. Also, High Efficiency Module had a big discrepancy of -10.0$\sim$-6.2% among 3 laboratories which have a less than 10msec light pulse duration time. This made low spectrum response speed so the Fill Factor decreased maximum output power under 10msec light pulse duration time

An Experimental Study on the Performance of Inverter Heat Pump with a Variation of Frequency and Capillary Size

  • Choi, Jong-Min;Kim, Yong-Chan;Kim, Jong-Yup
    • International Journal of Air-Conditioning and Refrigeration
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    • 제6권
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    • pp.27-35
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    • 1998
  • An experimental study was performed to investigate the optimum cycle of an inverter heat pump as a function of frequency. The performance of the inverter heat pump with the rated cooling capacity of 4,141 W(3,550kcal/h) was measured with a variation of frequency, indoor and outdoor temperature, and length of capillary tube in the psychrometric test room. As a base case, the inverter heat pump with the standard capillary length of l,000mm(optimum size for the frequency of 60Hz) and ASHRAE Test condition "A" was tested by varying frequency from 30Hz to 80Hz. Then, the optimum cycles were investigated by varying the length of capillary tube at each frequency level of 30, 60 and 80Hz. Based on the experimental data, the change of system characteristics between the optimum and the base case were analyzed for each selected frequency level. Generally, for low frequency level(30Hz), the longer length of the capillary tube compared with the standard size showed the higher energy efficiency ratio(EER), while for high frequency level(80Hz) the shorter length of the capillary tube showed the higher EER.

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인버터 열펌프의 주파수 및 모세관 길이 변화에 따른 시스템 성능특성의 실험적 연구 (An experimental study on the performance of inverter heat pump with a variation of frequency and capillary size)

  • 최종민;김용찬;김종엽;배영돈
    • 설비공학논문집
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    • 제9권1호
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    • pp.64-72
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    • 1997
  • An experiment study was performed to investigate the optimum cycle of an inverter heat pump as a function of frequency. The performance of the inverter heat pump with the rated cooling capacity of 4141W(3550kcal/h) was measured with a variation of frequency, indoor and outdoor temperature, and length of capillary tube in the psychrometric test room. As a base case, the inverter heat pump with the standard capillary length of 1000mm which was optimum size for the frequency of 60Hz and ARHRAE Test condition A was tested by varying frequency from 30Hz to 80Hz. Then, the optimum cycle was invesigated by varying the length of capillary tube at each frequency levels of 30, 60 and 80Hz. Based on the experimental data, the change of system characteristics between the optimum and the base case were analyzed for each selected frequency levels. Generally, for low frequency level(30Hz), the longer length of the capillary tube compared with the standard size showed the higher EER, while for high frequency level(80Hz) the shorter length of the capillary tube showed the higher EER.

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GMS/S-VISSR 자료로부터 Bispectral Thresholds 기법을 이용한 운량 분석에 관하여 (Cloud Cover Analysis from the GMS/S-VISSR Imagery Using Bispectral Thresholds Technique)

  • 서명석;박경윤
    • 대한원격탐사학회지
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    • 제9권1호
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    • pp.1-19
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    • 1993
  • A simple bispectral threshold technique which reflects the temporal and spatial characteristics of the analysis area has been developed to classify the cloud type and estimate the cloud cover from GMS/S-VISSR(Stretched Visible and Infrared Spin Scan Radiometer) imagery. In this research, we divided the analysis area into land and sea to consider their different optical properties and used the same time observation data to exclude the solar zenith angle effects included in the raw data. Statistical clear sky radiance(CSRs) was constructed using maximum brightness temperature and minimum albedo from the S-VISSR imagery data during consecutive two weeks. The CSR used in the cloud anaysis was updated on the daily basis by using CSRs, the standard deviation of CSRs and present raw data to reflect the daily variation of temperature. Thresholds were applied to classify the cloud type and estimate the cloud cover from GMS/S-VISST imagery. We used a different thresholds according to the earth surface type and the thresholds were enough to resolve the spatial variation of brightness temperature and the noise in raw data. To classify the ambiguous pixels, we used the time series of 2-D histogram and local standard deviation, and the results showed a little improvements. Visual comparisons among the present research results, KMA's manual analysis and observed sea level charts showed a good agreement in quality.

Impact of standard construction specification on thermal comfort in UK dwellings

  • Amoako-Attah, Joseph;B-Jahromi, Ali
    • Advances in environmental research
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    • 제3권3호
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    • pp.253-281
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    • 2014
  • The quest for enhanced thermal comfort for dwellings encompasses the holistic utilization of improved building fabric, impact of weather variation and amongst passive cooling design consideration the provision of appropriate ventilation and shading strategy. Whilst thermal comfort is prime to dwellings considerations, limited research has been done in this area with the attention focused mostly on non-dwellings. This paper examines the current and future thermal comfort implications of four different standard construction specifications which show a progressive increase in thermal mass and airtightness and is underpinned by the newly developed CIBSE adaptive thermal comfort method for assessing the risk of overheating in naturally ventilated dwellings. Interactive investigation on the impact of building fabric variation, natural ventilation scenarios, external shading and varying occupants' characteristics to analyse dwellings thermal comfort based on non-heating season of current and future weather patterns of London and Birmingham is conducted. The overheating analysis focus on the whole building and individual zones. The findings from the thermal analysis simulation are illustrated graphically coupled with statistical analysis of data collected from the simulation. The results indicate that, judicious integrated approach of improved design options could substantially reduce the operating temperatures in dwellings and enhance thermal comfort.

제주행원 풍력발전단지의 전압품질 및 연계기준 적합성 분석 (Voltage quality and Network Interconnection Standard Suitability in Jeju-Hangwon Wind Power Generation Farm)

  • 김세호;김일환;허종철
    • 한국태양에너지학회 논문집
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    • 제26권2호
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    • pp.53-59
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    • 2006
  • The number of wind generation installations are growing substantially in Jeju, Korea. Many of these installations are significant in size and directly connected to the distribution system. Utility grid interconnection standards for interconnecting non-utility distributed generation systems are essential to both power system company and generation company. These interconnection standards are important to utilities, customers, wind generation manufactures and nation. In this paper, it is investigated the voltage quality and the suitability of Jeju-Hangwon wind power generation farm by network interconnection technology standard.