• 제목/요약/키워드: real condition study

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전력소비를 이용한 실물경기지수 개발에 관한 연구 (Electricity Consumption as an Indicator of Real Economic Status)

  • 오승환;김태중;곽동철
    • 유통과학연구
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    • 제14권3호
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    • pp.63-71
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    • 2016
  • Purpose - A variety of indicators are used for the diagnosis of economic situation. However, most indicators explain the past economic situation because of the time difference between the measurement and announcement. This study aims to argue for the resurrection of an idea: electricity demand can be used as an indicator of economic activity. In addition, this study made an endeavor to develop a new Real Business Index(RBI) which could quickly represent the real economic condition based on the sales statistics of industrial and public electricity. Research design, data, and methodology - In this study monthly sales of industrial and public electricity from 2000 to 2015 was investigated to analyze the relationship between the economic condition and the amount of electricity consumption and to develop a new Real Business Index. To formulate the Index, this study followed next three steps. First, we decided the explanatory variables, period, and collected data. Second, after calculating the monthly changes for each variable, standardization and estimating the weighted value were conducted. Third, the computation of RBI finalized the development of empirical model. The principal component analysis was used to evaluate the weighted contribution ratio among 3 sectors and 17 data. Hodrick-Prescott filter analysis was used to verify the robustness of out model. Results - The empirical results are as follows. First, compatibility of the predictability between the new RBI and the existing monthly cycle of coincident composite index was extremely high. Second, two indexes had a high correlation of 0.7156. In addition, Hodrick-Prescott filter analysis demonstrated that two indexed also had accompany relationship. Third, when the changes of two indexes were compared, they were found that the times when the highest and the lowest point happened were similar, which suggested that it is possible to use the new RBI index as a complementing indicator in a sense that the RBI can explain the economic condition almost in real time. Conclusion - A new economic index which can explain the economic condition needs to be developed well and rapidly in a sense that it is useful to determine accurately the current economic condition to establish economic policy and corporate strategy. The salse of electricity has a close relationship with economic conditions because electricity is utilized as a main resource of industrial production. Furthermore, the result of the sales of electricity can be gathered almost in real time. This study applied the econometrics model to the statistics of the sales of industrial and public electricity. In conclusion, the new RBI index was highly related with the existing monthly economic indexes. In addition, the comparison between the RBI index and other indexes demonstrated that the direction of the economic change and the times when the highest and lowest points had happened were almost the same. Therefore, this RBI index can become the supplementary indicator of the official indicators published by Korean Bank or the statistics Korea.

A Study on the Parameter Estimation of DURUMI-II for the Fixed Right Elevator Using Flight Test Data

  • Park Wook-Je;Kim Eung-Tai;Seong Kie-Jeong;Kim Yeong-Cheol
    • Journal of Mechanical Science and Technology
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    • 제20권8호
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    • pp.1224-1231
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    • 2006
  • The stability and control derivatives of DURUMI-lI UAV using the flight test are obtained. The flight test data is gathered from the normal flight condition (normal mode) and the flight condition assumed as the right elevator fixed (fault mode). Using real-time parameter estimation techniques, applied to Fourier transform regression method, simulates the aircraft motion. From the result, the fault of control surface is to be detected. In this paper, the results of the real- time parameter estimation techniques are compared with the results of the Advanced Aircraft Analysis (AAA). Using the aerodynamic derivatives, it provides the base line of normal/failure for the control surface by using the on-line parameter estimation of Fourier transform regression. In flight, this approach maybe helpful to detect and isolate the fault of primary control surface. It is explained how to perform the flight condition assumed as the right elevator fixed in the flight test. Also, it is mentioned how to switch between the normal flight condition and the assumed fault flight condition.

Comparative Expression of Stress Related Genes in Response to Salt-stressed Aspen by Real-time RT-PCR

  • Ku, Ja-Jung;Kim, Yong-Yul
    • 한국자원식물학회지
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    • 제21권3호
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    • pp.210-215
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    • 2008
  • Gene-expression analysis is increasingly important in biological research, with real-time reverse PCR (RTPCR) becoming the method of choice for high-throughput and accurate expression profiling of selected genes. However, this technique requires important preliminary work for standardizing and optimizing the many parameters involved in the analysis. Plant stress studies are more and more based on gene expression. The analysis of gene expression requires sensitive and reproducible measurements for specific mRNA sequence. Several genes are regulated in response to abitoic stresses, such as salinity, and their gene products function in stress response and tolerance. The design of the primers and TaqMan probes for real-time PCR assays were carried out using the Primer $Express^{TM}$ software 3.0. The PCR efficiency was estimated through the linear regression of the dilution curve. To understand the expression pattern of various genes under salt stressed condition, we have developed a unique public resource of 9 stress-related genes in poplar. In this study, real-time RT-PCR was used to quantify the transcript level of 10 genes (9 stress-related genes and 1 house keeping gene) that could play a role in adaptation of Populus davidiana. Real-time RT-PCR analyses exhibited different expression ratios of related genes. The data obtained showed that determination of mRNA levels could constitute a new approach to study the stress response of P. davidiana after adaptation during growth in salinity condition.

건설현장 근로자의 안전의식과 안전교육 활성화 방안 (A Study for Construction Workers' Safety Consciousness and Safety Education Activation Methods)

  • 정지연;유희종
    • 한국안전학회지
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    • 제28권1호
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    • pp.47-51
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    • 2013
  • This research is the descriptive survey research targeting construction workers for searching a vitalization method on safety education by understanding the real condition of the sense of safety consciousness and the condition of safety education. The collected data of 147 workers are analyzed by using arithmetic mean, t-test, and ANOVA Analysis of Variance through SPSS PC program. This research investigated the real condition of safety consciousness, recognition on safety education, and the differences of safety consciousness depend on the general characteristic of subject. According to the result of the study, development of standardized safety consciousness assessment tool and institutionalization of safety education program is needed.

ROOM기법을 이용한 전자연동 소프트웨어 설계에 관한 연구 (A Study on the Design of Railway Electornic Interlocking Software Based on Real-Time Object-Oriented Modeling Technique)

  • 김종선;유지윤
    • 대한전기학회논문지:시스템및제어부문D
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    • 제50권9호
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    • pp.439-446
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    • 2001
  • This paper considers the design technique of the real-time control algorithm to implement the electronic interlocking system which is the most important station control system in railway signal field. The proposed technique consists of the structure design and the detail design which are based on the ROOM(Real-Time Object-Oriented Modeling). The structure design is designed with a modeling using the heuristic search technique which, at first, catch and make out the specific requested condition, and then, is designed on the requested condition. The detail design can be implemented if it may get the satisfying values through the repetitive modeling after comparing and examining the data obtained from the structure design in order for the more reliable and accurate system to be implemented. The technique proposed in this paper is implemented with C++ language which is easy to be transferred and compatible with the existing interfaces, and also the operating system is designed and simulated on the VRTX which is a real-time operating system. This proposed technique is applied to the typical station model in order to prove the validity as verifying the performance of the modeled station.

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다물체 동역학 해석기술을 이용한 핸드레일의 슬립특성 개선 (Improvement of Handrail Slippage Characteristics Using Multi-Body Dynamic Analysis Technique)

  • 박찬종
    • 대한기계학회논문집A
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    • 제28권9호
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    • pp.1422-1428
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    • 2004
  • In this paper, computer simulation model of handrail band including pulley-driving system is developed to calculate handrail slippage. This handrail simulation model is validated with test result within operating range and used to predict its slippage behavior with respect to variation of 4 different design parameters considering the applicability into the real handrail system. Based upon this parameter study, optimal condition for handrail slippage improvement is proposed without time-consuming and costly experiments of the real handrail system. And then performance improvement of handrail slippage complied with safety code is achieved after applying the optimal condition into the real handrail band system.

Stress distribution on the real corrosion surface of the orthotropic steel bridge deck

  • Kainuma, Shigenobu;Jeong, Young-Soo;Ahn, Jin-Hee
    • Steel and Composite Structures
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    • 제18권6호
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    • pp.1479-1492
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    • 2015
  • This study evaluated the localized stress condition of the real corroded deck surface of an orthotropic steel bridge because severe corrosion damage on the deck surface and fatigue cracking were reported. Thus, a three-dimensional finite element (FE) analysis model was created based on measurements of the corroded orthotropic steel deck surface to examine the stress level dependence on the corrosion condition. Based on the FE analysis results, it could be confirmed that a high stress concentration and irregular stress distribution can develop on the deck surface. The stress level was also increased by approximately 1.3-1.5 times as a result of the irregular corroded surface. It was concluded that this stress concentration could increase the possibility of fatigue cracking in the deck surface because of the surface roughness of the orthotropic steel bridge deck.

PSCAD/EMTDC를 이용한 풍력발전시스템의 과도현상 시뮬레이션에 관한 연구 (Study on the Transient Phenomenon Simulation of Wind Power Generation System using PSCAD/EMTDC)

  • 한상근;박민원;유인근
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.309-312
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    • 2002
  • For the purpose of more effective simulation of the utility interactive WPGS(Wind Power Generation System) the SWRW (Simulation method for WPGS using Real Weather condition) is used in this paper, in which those of three topics for the WPGS simulation. user-friendly method, applicability to grid-connection and the utilization of the real weather conditions, are satisfied. The simulation of the WPGS using the real weather condition including components modeling of wind turbine system is achieved by introducing the interface method of a non-linear external parameter and FORTRAN using PSCAD/EMTDC. The simulations of steady-state and transient-state are performed effectively by the introduced simulation method. The generator output and current supplied into utility can be obtained by the steady-state simulation, and THD can be achieved by analyzing the results as well. The transient - state of the WPGS can be analyzed by the simulation results of over cut-out wind speed.

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Bus Reconfiguration Strategy Based on Local Minimum Tree Search for the Event Processing of Automated Distribution Substations

  • Ko Yun-Seok
    • KIEE International Transactions on Power Engineering
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    • 제5A권2호
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    • pp.177-185
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    • 2005
  • This paper proposes an expert system that can enhance the accuracy of real-time bus reconfiguration strategy by adopting the local minimum tree search method and that can minimize the spreading effect of the fault by considering the operating condition when a main transformer fault occurs in an automated substation. The local minimum tree search method is used to expand the best-first search method. This method has the advantage that it can improve the solution performance within the limits of the real-time condition. The inference strategy proposed expert system consists of two stages. The first stage determines the switching candidate set by searching possible switching candidates starting from the main transformer or busbar related to the event. The second stage determines the rational real-time bus reconfiguration strategy based on heuristic rules from the obtained switching candidate set. Also, this paper proposes generalized distribution substation modeling using graph theory, and a substation database based on the study results is designed.

재한 중국 조선족의 생활 형태 및 삶의 질에 관한 연구 (A Study on Real-Life Conditions and Quality of Life among Korean-Chinese in Korea)

  • 최덕경
    • 가족자원경영과 정책
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    • 제5권1호
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    • pp.1-13
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    • 2001
  • The purpose of this study was not only to identify real-life conditions of Korean-Chinese in Korea(clothing habits, eating habits, housing habits, economic life and leisure activities) but also to reveal the related variables that shall affect life quality. The subjects were selected from Korean-Chinese in Korea related to ‘Compatriots House’. The survey was conducted from June 20th to July 5th, 2000. A total of 225 questionnaires out of 350 were used as the final data analysis. All data were analyzed using the SAS/PC for frequency, percentage, F-test and Regression analysis. The study revealed the following results. 1. Significant differences were found in life quality of Korean-Chinese in Korea according to age(p<.05), optimum income (p<.001), health condition(p<.001), education level(p<.005), and entry motivation(p<.05). 2. Variable such as optimum income(β=.334) education level(β=-.190), monthly income(β=.170), health condition(β=.151), and self-esteem(β=.133) affected life quality of Korean-Chinese in Korea. Korean-Chinese’s life quality was explained by these variable(35%). The optimum income variable was the primary influential factor.

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