• 제목/요약/키워드: Weather-conditions

검색결과 1,805건 처리시간 0.025초

Photovoltaic Generation System Simulation using Real Field Weather Conditions

  • 박민원;유인근
    • 전기전자학회논문지
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    • 제5권2호
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    • pp.121-127
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    • 2001
  • Actual system apparatuses are necessary in order to verify the efficiency and stability of photovoltaic(PV) generation systems considering the size of solar panel, the sort of converter type, and the load conditions and so on. Moreover, it is hardly possible to compare a certain MPPT control scheme with others under the exactly same weather and load conditions as well. For the purpose of solving above mentioned difficulties in a laboratory basis, a transient simulation of PV generation system using real field weather conditions is indispensable. A straightforward simulation scheme with cost effective hardware structures under real weather conditions is proposed in this paper using EMTDC type of transient analysis simulators. Firstly, a solar cell has been modeled with VI characteristic equations, and then the real field data of weather conditions are interfaced to the EMTDC through Fortran program interface method. As a result, the stability and the efficiency analysis of PV generation systems according to various hardware structures and MPPT controls are easily possible under the exactly same weather conditions.

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기상조건, 방위각 및 경사각에 따른 태양광발전시스템 출력 분석 (PV System Output Analysis Based on Weather Conditions, Azimuth, and Tilt Angle)

  • 이상혁;권오현;이경수
    • Current Photovoltaic Research
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    • 제5권1호
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    • pp.38-42
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    • 2017
  • PV system output is determined according to the weather conditions, the azimuth and tilt angle. Weather conditions are changing every moment and it seems to vary according to the daily, monthly, and annual basis. The azimuth and tilt angle is decided along the site conditions for the PV system installation. This paper analyzed the PV system output through the changing the weather conditions, the azimuth, and tilt angle. We compared the TMY data and analysis of the two major weather institutes which are KMA and METEONORM. PV system output trend were analyzed by changing the azimuth and tilt angle. We used simulation tool, which is named PVsyst for the entire PV system analysis.

Time-Profit Trade-Off of Construction Projects Under Extreme Weather Conditions

  • Senouci, Ahmed;Mubarak, Saleh
    • Journal of Construction Engineering and Project Management
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    • 제4권4호
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    • pp.33-40
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    • 2014
  • Maximizing the profitability and minimizing the duration of construction projects in extreme weather regions is a challenging objective that is essential for project success. An optimization model is presented herein for the time-profit trade-off analysis of construction projects under extreme weather conditions. The model generates optimal/near optimal schedules that maximize profit and minimize the duration of construction projects in extreme weather regions. The computations in the model are organized into: (1) a scheduling module that develops practical schedules for construction projects, (2) a profit module that computes project costs (direct, indirect, and total) and project profit, and (3) a multi-objective module that determines optimal/near optimal trade-offs between project duration and profit. One example is used to show the impact of extreme weather on construction time and profit. Another example is used to show the model's ability to generate optimal trade-offs between the time and profit of construction projects under extreme weather conditions.

기상변화와 일개 대학병원 외래환자 예약부도와의 관련성 (The Association between Weather Conditions and the Number of No-Show Patients at an Academic Medical Center)

  • 박일순;정상진;신환호
    • 보건의료산업학회지
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    • 제11권4호
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    • pp.41-51
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    • 2017
  • Objectives : This study investigates the association between weather conditions and the rate of no-shows at an academic medical center. Methods : Electronic data regarding medical appointments atover the course ofone academic year (2016.03~2017.02) were used for analysis. Characteristics of weather conditions and the daily number of no-shows were compared by Chi-square test. A logistic regression was run to determine if certain aspects of weather affected the rate of no-shows. Results : The results reveal an overall no-show rate of 6.8% that appears to vary in accordance with specific weather conditions. Lower average temperatures, in particular, corresponded with a higher rate of no-show patients. This may indicate that o-show rates in autumn and winter can be expected to exceed those during spring. Conclusions : This study investigates the association between no-show patients and weather conditions, and offers suggestions for augmenting this loss. One recommendation is to begin conducting investigations nationwide in order to provide more useful information.

시스템 구성요소 통합 및 현업서비스 구축 (Implementation of a Weather Hazard Warning System at a Catchment Scale)

  • 신용순
    • 한국농림기상학회:학술대회논문집
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    • 한국농림기상학회 2014년도 추계 학술발표논문집
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    • pp.74-85
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    • 2014
  • This study is a part of "Early Warning Service for Weather Risk Management in Climate-smart Agriculture", describes the delivery techniques from 840 catchment scale weather warning information using 150 counties unit special weather report(alarm, warning) released from KMA(Korea Meteorological Administration) and chronic weather warning information based on daily weather data from 76 synoptic stations. Catchment weather hazard warning service express a sequential risk index map generated by countries report occurs and report grade(alarm, warning) convert to catchment scale using zonal summarizing method. Additional services were chronic weather warning service at crop growth and accumulated more than 4 weeks, based on an unsuitable weather conditions, representing a relative risk compared to its catchment climatological normal conditions (normal distribution ) in addition to special weather report. Service provided by a real-time catchment scale map overlaid with VWORLD open platform operated by Ministry of Land, Infrastructure and Transport. Also provide a foundation for weather risk information to inform individual farmers to farm located within the catchment zone warning occur.

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Development of a Safety Management Support System for Construction Sites Using Pinpoint Weather Forecast Information

  • Moe SHIGAKI;Kentaro HAYAKAWA;Hiroyuki AKITA;Michiko SHIMIZU;Mika SAKURAMOTO
    • 국제학술발표논문집
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    • The 10th International Conference on Construction Engineering and Project Management
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    • pp.256-263
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    • 2024
  • The increasing occurrence of abnormal weather conditions such as unusually heavy rains and strong winds adversely affects construction work. However, although these phenomena are localized, conventional weather forecasts have insufficient spatial resolution and update frequency to accurately predict weather conditions at construction sites. To address this issue, we introduced a pinpoint weather forecasting technology that improves spatial resolution and update frequency. The weather information obtained from this technology is processed and provided to construction sites in a comprehensible state, which enables construction workers to better prepare for weather conditions, thereby reducing the risk of accidents and delays. Furthermore, a safety management system was developed based on the relationship between weather and labor accidents. Predicting workplace accidents that are likely to occur on that day based on the impact of weather on the body enabled performing safety awareness activities, such as morning and lunch meetings, from a new perspective, improving safety awareness among construction workers and reducing the number of accidents on construction sites. This paper describes the development process of the proposed system and the utilization of weather forecasting at construction sites, which can be applied to other industries and contribute to improving safety and efficiency in various fields.

기상조건이 적외선 열화상에 미치는 영향 분석 (Analysis on the Effects by Weather Conditions of Infrared Thermography)

  • 임용배;김기현;최명일;박치현;배석명;조성원
    • 전기학회논문지P
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    • 제56권3호
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    • pp.142-147
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    • 2007
  • Infrared thermography is one of the most valuable and cost-effective diagnostic techniques for predictive maintenance on electrical systems. For the electric installations, the thermographies can identify major problems, which if left unattended could lead to breakdowns. The result thermal images depend upon operator skills, inspection technique, and load and weather conditions. When the thermographer is applied to remote monitoring, the conditions of the systems are not perfectly analyzed because operators are hard to know the weather's effects of the installed place. Therefore, this paper defines the effects by weather conditions which will influence the final results. The purpose of this paper is to define the weather effects that a thermographer needs to consider for successful condition analysis.

주변온도와 일사량을 고려한 PV Cell의 전기적 특성 분석 (Analysis on Electrical Characteristics of PV Cells considering Ambient Temperature and Irradiance Level)

  • 박현아;김효성
    • 전력전자학회논문지
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    • 제21권6호
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    • pp.481-485
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    • 2016
  • When analyzing economic feasibility for installing a PV generation plant at a certain location, the prediction of possible annual power production at the site using the target PV panels should be conducted on the basis of the local weather data provided by a local weather forecasting office. In addition, the prediction of PV generating power under certain weather conditions is useful for fault diagnosis and performance evaluation of PV generation plants during actual operation. This study analyzes PV cell characteristics according to a variety of weather conditions, including ambient temperature and irradiance level. From the analysis and simulation results, this work establishes a proper model that can predict the output characteristics of PV cells under changes in weather conditions.

Estimation of Doppler Spectrum Modes in a Weather Radar for Detection of Hazardous Weather Conditions

  • Lee, Jong-Gil
    • 한국통신학회논문지
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    • 제27권3A호
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    • pp.205-210
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    • 2002
  • In a Doppler weather radar, high resolution windspeed profile measurements are needed to provide the reliable detection of hazardous weather conditions. For this purpose, the pulse pair method is generally considered to be the most efficient estimator, However, this estimator has some bias errors due to asymmetric spectra and may yield meaningless results in the case of a multimodal return spectrum. Although the poly-pulse pair method can reduce the bias errors of skewed weather spectra, the modes of spectrum may provide more reliable information than the statistical mean for the case of a multimodal or seriously skewed spectrum. Therefore, the idea of relatively simple mode estimator for a weather radar is developed in this paper, Performance simulations show promising results in the detection of hazardous weather conditions.

다중회귀를 이용한 기후와 오손도 간의 상관관계 분석 (Analysis of the Correlation on the Weather Conditions and the Contamination Degree Using Mu lisle Regression Method)

  • 심규일;최남호;김종석;한상옥
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2001년도 학술대회논문집
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    • pp.199-202
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    • 2001
  • This paper presents the correlation on the contamination degree and weather conditions using the multiple regression of the statistic method. The cotamination is a significant factor in the insulation system. The major factor is natural contamination, and the most is the salt. The salt contamination is occured by the weather conditions. The weather contaminations are wind, precipitation, temperature, relative humidity, etc. The effects of those are different, and the correlation is showed numerically by using the multiple regression method of the statistic method. With this, the estimation of the equivalent salt deposit density(ESDD) becomes possible by the changes of the weather conditions.

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