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Analyzing on the Fluctuation Characteristics of Management Condition of Construction Company (건설업체 경영상태 변동에 대한 특성 분석)

  • Jang, Ho-Myun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.2
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    • pp.1118-1125
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    • 2014
  • The past IMF foreign exchange crisis and subprime financial crisis had a big influence on variability of macroeconomics, even if the origin of its occurrence might be different. This not only had a significant infrequence on the overall industries, but also produced many insolvent companies by being closely linked with a management environment of an individual construction company leading the construction industry. The purpose of this research is to investigate characteristics of management condition of construction company according to the size of construction company using KMV model developed on the basis of the Black & Scholes option pricing theory. This research has set 28 construction companies listed to KOSPI/KOSDAQ for applying the KMV model and measuring the level of the default risk of construction companies. The data was retrieved from TS2000 established by Korea Listed Companies Association (KLCA), Statistics Korea. The analysis period is between first quarter of 2004 and fourth quarter of 2010. This research examine characteristics of the level and fluctuation process of the management condition of construction company according to the size of construction company.

Some Properties of an Isolate of Peanut stunt virus Isolated from White Clover (Trifolium repens L.) (토끼풀에서 분리한 Peanut stunt virus의 성질)

  • Jung, Goo-Ho;Jeon, Yong-Woon;Choi, Jang-Kyung;Hong, Jin-Sung;Ryu, Ki-Hyun;Lee, Sang-Yong
    • Research in Plant Disease
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    • v.14 no.1
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    • pp.71-75
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    • 2008
  • An isolate of Peanut stunt virus (PSV), named as Tr-PSV, was isolated from white clover (Trifolium repens L) showing mosaic symptom. Tr-PSV systemically infected all plants tested in the Nicotiana spp. and induced local lesions on inoculated leaves of Chenopodium amaranticolor. However, Tr-PSV induced typical mosaic symptoms as ER-PSV on Vigna unguiculata 5 to 6 days after inoculation, while Fny-CMV used as a control virus of Cucumovirus produced local lesions on inoculated leaves. In dsRNA analysis, Tr-PSV consisted of four dsRNAs, but satellite RNA was not detected. The cDNA of coat protein gene of Tr-PSV was amplified by RT-PCR using a Cucumovirus-specific single pair primers that designed to amplify a DNA fragment of approximately 950 bp. By restriction mapping analysis using RFLP of the RT-PCR products and by serological properties of gel diffusion test, Tr-PSV belongs to a typical member of PSV subgroup I. This is the first report on the occurrence of PSV in white clover in Korea.

Development of Determination Criteria Installing Crash Cushion on Freeway Off-Ramp (고속도로 진출램프 부근의 충격흡수시설 설치여부 판단기준 개발에 관한 연구)

  • 하태준;박제진;오재철
    • Journal of Korean Society of Transportation
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    • v.20 no.7
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    • pp.107-116
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    • 2002
  • Crash Cushion is a kind of safety facilities on roadside which acts the role of absorbing impact energy when vehicles are driven out of normal route such as Gore area of freeway off ramp. Criteria for severity index considering accident occurrence possibility are needed to have strong effect on installing the facilities. However, present criteria for establishing crash cushion design do not include such processes. Therefore, the paper presents two kinds of study to develop criteria for severity index. First of all, development of accident forecasting model on freeway off ramp is presented. The module is a relationship between accidents and road environment by negative binomial distribution (NB) which is called to reflect very well quality of accidents at Gore of crash cushion installed freeway Secondly, freeway exiting behavior model is developed because the human factor is the most important one. However, many literatures have shown between road environment and accidents which are more quantitative than human factor. The study supposed advanced process steps on actual freeway and analysed correlation between variables and accidents. The criteria for severity index is presented to determine whether to install or not by benefit cost analysis for each module. The standard for severity index will help to determine whether to install the crash cushion or not and to estimate severity for freeway and off ramp.

An Investigation on Intellectual Structure of Social Sciences Research by Analysing the Publications of ICPSR Data Reuse (ICPSR 데이터 재이용 저작물 분석을 통한 사회과학 분야의 지적구조 분석)

  • Chung, EunKyung
    • Journal of the Korean Society for Library and Information Science
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    • v.52 no.1
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    • pp.341-357
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    • 2018
  • Due to the paradigm of open science and advanced digital information technology, data sharing and re-use have been actively conducted and considered data-intensive in a wide variety of disciplines. This study aims to investigate the intellectual structure portrayed by the research products re-using the data sets from ICPSR. For the purpose of this study, a total of 570 research products published in 2017 from the ICPSR site were collected and analyzed in two folds. First, the authors and publications of those research products were analyzed in order to show the trends of research using ICPSR data. Authors tend to be affiliated with university or research institute in the United States. The subject areas of journals are recognized into Social Sciences, Health, and Psychology. In addition, a network with clustering analysis was conducted with using co-word occurrence from the titles of the research products. The results show that there are 12 clusters, mental health, tabocco effect, disorder in school, childhood, and adolescence, sexual risk, child injuries, physical activity, violent behavior, survey, family role, women, problem behavior, gender differences in research areas. The structure portrayed by ICPSR data re-uses demonstrates that substantial number of studies in Medicine have been conducted with a perspective of social sciences.

Long-term variation of zooplankton around Dokdo in the East Sea (독도 인근해역 동물플랑크톤 장기간 특성)

  • Kang, Jung-Hoon;Kim, Woong-Seo;Kwon, Oh Youn;Cho, Kyuhee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.9
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    • pp.422-430
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    • 2016
  • We investigated the abundance and composition of the zooplankton community around Dokdo in the East Sea from 2006 to 2015. Zooplankton samples were collected in the surface mixed layer by vertical hauls using a standard type net at the monitoring stations. There were no clear long-term trends in the average temperature and salinity, but relatively low salinity was recorded in the summer of 2013 and 2015. The average abundances of zooplankton in the summer increased by two orders of magnitude from $317inds./m^3$ in 2008 to $10,242inds./m^3$ in 2015. This long-term increase was accompanied by a slight increase in the chlorophyll-a concentration and a decrease in the catch of potential crucial predators (anchovy, mackerel pike, squid, herring and horse mackerel) in the study area. The dominant zooplankton, accounting for most of the long-term increase, consisted of appendicularian (Oikopleura spp.), which showed a steady increase since 2012, summer species such as Noctiluca scintillans and the cladoceran Penilia avirostris, which showed an abrupt increase, and the copepod Paracalanus parvus s.l., which showed a rapid increase after its first occurrence in summer 2010. These results suggest that the long-term increase of zooplankton could be related to the increase in the concentration of prey and the decrease in the predation pressure of potential predators around Dokdo in the study area.

ESD(Exponential Standard Deviation) Band centered at Exponential Moving Average (지수이동평균을 중심으로 하는 ESD밴드)

  • Lee, Jungyoun;Hwang, Sunmyung
    • Journal of Intelligence and Information Systems
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    • v.22 no.2
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    • pp.115-125
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    • 2016
  • The Bollinger Band indicating the current price position in the recent price action range is obtained by adding/substracting the simple standard deviation (SSD) to/from the simple moving average (SMA). In this paper, we first compare the characteristics of the SMA and the exponential moving average (EMA) in the operator's point of view. A basic equation is obtained between the interval length N of the SMA operator and the weighting factor ${\rho}$ of the EMA operator, that makes the centers of the 1st order momentums of each operator impulse respoinse identical. For equivalent N and ${\rho}$, frequency response examples are obtained and compared by using the discrete time Fourier transform. Based on observation that the SMA operator reacts more excessively than the EMA operator, we propose a novel exponential standard deviation (ESD) band centered at the EMA and derive an auto recursive formula for the proposed ESD band. Practical examples for the ESD band show that it has a smoother bound on the price action range than the Bollinger Band. Comparisons are also made for the gap corrected chart to show the advantageous feature of the ESD band even in the case of gap occurrence. Trading techniques developed for the Bollinger Band can be straight forwardly applied to those for the ESD band.

Model Predictive Control for Distributed Storage Facilities and Sewer Network Systems via PSO (분산형 저류시설-하수관망 네트워크 시스템의 입자군집최적화 기반 모델 예측 제어)

  • Baek, Hyunwook;Ryu, Jaena;Kim, Tea-Hyoung;Oh, Jeill
    • Journal of the Korean Institute of Intelligent Systems
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    • v.22 no.6
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    • pp.722-728
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    • 2012
  • Urban sewer systems has a limitation of capacity of rainwater storage and problem of occurrence of untreated sewage, so adopting a storage facility for sewer flooding prevention and urban non-point pollution reduction has a big attention. The Korea Ministry of Environment has recently introduced a new concept of "multi-functional storage facility", which is crucial not only in preventive stormwater management but also in dealing with combined sewer overflow and sanitary sewer discharge, and also has been promoting its adoption. However, reserving a space for a single large-scale storage facility might be difficult especially in urban areas. Thus, decentralized construction of small- and midium-sized storage facilities and its operation have been introduced as an alternative way. In this paper, we propose a model predictive control scheme for an optimized operation of distributed storage facilities and sewer networks. To this aim, we first describe the mathematical model of each component of networks system which enables us to analyze its detailed dynamic behavior. Second, overflow locations and volumes will be predicted based on the developed network model with data on the external inflow occurred at specific locations of the network. MPC scheme based on the introduced particle swarm optimization technique then produces the optimized the gate setting for sewer network flow control, which minimizes sewer flooding and maximizes the potential storage capacity. Finally, the operational efficacy of the proposed control scheme is demonstrated by simulation study with virtual rainstorm event.

A Study on Behavioral Factors for the Safely of Ambulance Driving (일부지역에서 구급차운전자의 구급차 안전운전 운행행태에 관한 연구)

  • Jo, Jeanman;Lee, Byung-Ju
    • The Korean Journal of Emergency Medical Services
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    • v.1 no.1
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    • pp.100-111
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    • 1997
  • This is the first Korea study to evaluate the effects od the safety of ambulance driving and the occurrence of ambulance traffic accidents and to provide basic informaion for the description of various factors to reduce the ambulance traffic accidents. The major insturment of this study were Krean Self-Analysis Driver Opinionnaire. Questionnaire contains 8 items which measure driver's opinions or attitudes : driving courtesy, emotion, traffic law, speed, vehicle conditions, the use of drugs, high-risk behaviors, and human factors. To take the analysis of data, the total of 350 divers were investigated ambulance divers and others in Taejon City and others (6 City) from 1996. 1. July to 1996. 31. July. The data were analyzed by the descriptive statistics and the logistic regression - path analysis - with SPSS and SAS package program. The result are as follows : 1. There was desirable attitude group(16.2%) and undesirable attitude group(17.6%) on safety ambulance driving. 2. It have suggested that risk factors of ambulance traffic accidents much affected with emotion and speed control on safety ambulance driving < Y(Accdient) = -2.64 + 0.57 $X_1$ (Emotion Control) + 0.30 $X_2$(Seed control) + E > and motor traffic acident much affected with emotion control and high-risk behavior on safety driving < Y(Accident) = -1.11 + 0.33 $X_1$(Emotion Control) + 0.29 $X_2$(High-risk Behvior) + E > 4. The primary emphassis of ambulance drivers was make us realized that improthatnt factors on safety ambulance driving were 1)making way for emergent ambulance, 2)driver's career, 3)The ability of emergency medical technics, and the knowledge or under standing of ambulance way difficut(or easy) of accdess. 5. Almost 96.6% of respondents have agreed to necessity of emergency medical technics for ambulance drivers. 6. Almost 94.6% of respondents have consented to necessity of emergtency medical technicians for ambulance driving. 7. It have suggested that the proportion of traffic accident proportion by desitable attitude group(16.7%) was much less than that of undesirable attitude group(30.8%) on safety ambulance driving(P < 0.05)/Ps) Accidents are unplanned, unforesen incidents which can lead to harmful or unfortunate outcomes, Collisons are not accidents, since the basic cause of the majority of collisons invovles high-risk human behavior. Although there are many factors which contribute to accident causation, four basic factors seem to predominate in most traffic related situations. These four factors include: the human factor, the vehicle factor, the environmental factors and destination factor(Peto G. et al. 1995).

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Research and Development for Decontamination System of Spent Resin in Hanbit Nuclear Power Plant (한빛원전 폐수지 제염공정 개발연구)

  • Sung, Gi Hong
    • Journal of Radiation Industry
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    • v.9 no.4
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    • pp.217-221
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    • 2015
  • When reactor coolant leaks occur due to cracks of a steam generator's tube, radioactive materials contained in the primary cooling water in nuclear power plant are forced out toward the secondary systems. At this time the secondary water purification resin in the ion exchange resin tower of the steam generator blowdown system is contaminated by the radioactivity of the leaked radioactive materials, so we pack this in special containers and store temporarily because we could not dispose it by ourselves. If steam generator tube leakage occurs, it produces contaminated spent resins annually about 5,000~7,000 liters. This may increase the amount of nuclear waste productions, a disposal working cost and a unit price of generating electricity in the plant. For this reasons, it is required to develop a decontamination process technique for reducing the radioactive level of these resins enough to handle by the self-disposal method. In this research, First, Investigated the structure and properties of the ion exchange resin used in a steam generator blowdown system. Second, Checked for a occurrence status of contaminated spent resin and a disposal technology. Third, identified the chemical characteristics of the waste radionuclides of the spent resin, and examined ionic bonding and separation mechanism of radioactive nuclear species and a spent resin. Finally, we carried out the decontamination experiment using chemicals, ultrasound, microbubbles, supercritical carbon dioxide to process these spent resin. In the case of the spent resin decontamination method using chemicals, the higher the concentration of the drug decontamination efficiency was higher. In the ultrasound method, foreign matter of the spent resin was removed and was found that the level of radioactivity is below of the MDA. In the microbubbles method, we found that the concentration of the radioactivity decreased after the experiment, so it can be used to the decontamination process of the spent resin. In supercritical carbon dioxide method, we found that it also had a high decontamination efficiency. According to the results of these experiments, almost all decontamination method had a high efficiency, but considering the amounts of the secondary waste productions and work environment of the nuclear power plant, we judged the ultrasound and supercritical carbon dioxide method are suitable for application to the plant and we established the plant applicable decontamination process system on the basis of these two methods.

The Impacts of Reporting Choice on Asymmetric Cost Behavior - Focused on Korean and Japanese Manufacturing Firms - (회계선택이 비대칭적 원가행태에 미치는 영향 - 한국, 일본 제조기업을 중심으로 -)

  • Noh, Gil-Kwan;Kim, Dong-Il
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.10
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    • pp.452-458
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    • 2019
  • The purpose of this study is to analyze how managers' reporting choices affect asymmetric cost behaviors in manufacturing firms in Korea and Japan. In order to analyze the contents, SG&A, COGS, and operating expenses (OE), which were the targets of the previous studies, were analyzed using the operating costs paid in cash (OC) and the operating expenses before depreciation (OEBD) proposed by Shust and Weiss (2014). The differentiation of cost behavior was analyzed. The analysis revealed, first, that both Korea and Japan showed the difference between cost behavior of OE and OC. Specifically, the cost stickiness of OC was higher than that of OE. In particular, it showed that Korea firms have a higher intensity of tangible fixed assets that are weakening the cost stickiness compared to Japanese firms. Second, the occurrence of depreciation costs weakens the cost stickiness in both countries. Lastly, the higher the debt ratio, the more aggressively the cost reduction of Japanese companies. We hope that this study will help to improve the relationship between the two countries at the academic level when the Korea-Japan relationship cools down.