• Journal of Welding and Joining
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• 제23권1호
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• pp.35-40
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• 2005

In this paper, static and fatigue load tests for the specimens, components and carbody were carried out to investigate the strength of welded joints in aluminum rolling stock. Tensile test results showed that the static strength of welded joint for the heat-treated alloy is reduced significantly and fatigue strength data are scattered by the welding imperfections. Component and whole carbody fatigue test results showed agreements with the design fatigue strength standards for specimens of the same joint detail. Test results revealed that full penetration welding and strict management of welding procedure are crucial for securing the strength of welded joint in aluminum carbody.

• 대한산업공학회지
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• 제3권1호
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• pp.55-59
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• 1977

This paper develops a portfolio management game applicable to Korean Stock Market with an emphasis on teaching and training aid. It allows each participant to start out with a certain amount of money and pick his favorable stocks from a list of stocks chosen by instructor. Each participant must make a transaction at each time period and he gets a readout that states his individual performance, i.e., stock lists, cash on hand, net worth, transactions he has made and rank in accordance with his net worth. This game package consists of 10 subprograms and 7 files written with Fortran language for use on the Nova 840 computer and is divided into 3 main categories according to their functions, i.e., book-keeping function, data processing function and information searching function. This package may be used for training portfolio decison makings in the stock market and for comparing various investment methods through hypothetical investments.

• Journal of Forest and Environmental Science
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• 제32권2호
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• pp.120-128
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• 2016

Forest sequesters large terrestrial carbon which is stored in the biomass of tree and plays a key role in reducing atmospheric carbon. Thus, the objectives of the present study were to assess the growing stock, above ground biomass and carbon in trees of Ponda watershed of Rajouri district (J&K). IRS-P6 LISS-III satellite data of October 2010 was used for preparation of land use/land cover map and forest density map of the study area by visual interpretation. The growing stock estimation was done for the study area as well as for the sample plots laid in forest and agriculture fields. The growing stock and biomass of trees were estimated using species specific volume equations and using specific gravity of wood, respectively. The total growing stock in the study area was estimated to be $0.25million\;m^3$ which varied between $85.94m^3/ha$ in open pine to $11.58m^3/ha$ in degraded pine forest. However in agriculture area, growing stock volume density of $14.85m^3/ha$ was recorded. Similarly, out of the total biomass (0.012 million tons) and carbon (0.056 million tons) in the study area, open pine forest accounted for the highest values of 43.74 t/ha and 19.68 t/ha and lowest values of 5.68 t/ha and 2.55 t/ha, respectively for the degraded pine forest. The biomass and carbon density in agriculture area obtained was 5.49 t/ha and 2.47 t/ha, respectively. In all the three forest classes Pinus roxburghii showed highest average values of growing stock volume density, biomass and carbon.

• 산경연구논집
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• 제12권3호
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• pp.43-49
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• 2021

Purpose: This study attempted to examine the risk of stock price plunge according to the firm's management strategy. Prospector firms value innovation and have high uncertainties due to rapid growth. There is a possibility of lowering the quality of financial reporting in order to meet market expectations while withstanding the uncertainty of the results. In addition, managers of prospector firms enter into compensation contracts based on stock prices, thus creating an incentive to withhold negative information disclosure to the market. Prospector firms' information opacity and delays in disclosure of negative information are likely to cause a sharp decline in share prices in the future. Research design, data and methodology: This study performed logistic analysis of KOSPI listed firms from 2014 to 2017. The independent variable is the strategic index, and is calculated by considering the six characteristics (R&D investment, efficiency, growth potential, marketing, organizational stability, capital intensity) of the firm. The higher the total score, the more it is a firm that takes a prospector strategy, and the lower the total score, the more it is a firm that pursues a defender strategy. In the case of the dependent variable, a value of 1 was assigned when there was a week that experienced a sharp decline in stock prices, and 0 when it was not. Results: It was found that the more firms adopting the prospector strategy, the higher the risk of a sharp decline in the stock price. This is interpreted as the reason that firms pursuing a prospector strategy do not disclose negative information by being conscious of market investors while carrying out venture projects. In other words, compensation contracts based on uncertainty in the outcome of prospector firms and stock prices increase the opacity of information and are likely to cause a sharp decline in share prices. Conclusions: This study's analysis of the impact of management strategy on the stock price plunge suggests that investors need to consider the strategy that firms take in allocating resources. Firms need to be cautious in examining the impact of a particular strategy on the capital markets and implementing that strategy.

• 국제지역연구
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• 제15권1호
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• pp.219-240
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• 2011

본 연구는 주가 및 부동산가격 변화에 의한 화폐수요함수의 자산효과를 분석하였다. 부동산가격 자료의 획득이 가능한 10개국, 25개 통화단위를 대상으로 분석하였으며, Johansen 공적분 검정에 추가하여 Pesaran, Shin and Smith의 한계검정을 적용하였다. 또한, 효율적인 공적분벡터의 추정을 위하여 Stock and Watson의 DOLS를 적용하였다. 분석결과, 화폐수요함수에 주가와 부동산가격을 포함시킬 경우 장기균형관계의 성립 가능성이 월등히 증가하였다. 특히 ARDL-한계검정에 의하면 12개 통화단위는 자산 가격을 포함하는 경우에만 공적분관계가 존재하는 것으로 나타났다. 이러한 결과들은 자산가격의 변화가 장기화폐수요에 매우 유의한 영향을 준다는 의미이다. DOLS에 의한 공적분 벡터의 추정결과에서도 주가와 부동산가격이 매우 유의한 영향을 주는 것으로 나타났다. 주가는 12개 통화단위에서 통계적으로 유의한 영향을 미치는 반면 부동산가격은 19개 통화단위에서 통계적으로 유의하였다. 특히 부동산가격은 싱가포르 M1을 제외하고 나머지 모든 국가의 통화단위에서 통계적으로 유의하게 나타나 장기 화폐수요함수 추정에서 부동산시장의 중요성이 부각된다. 한편 주가와 부동산가격의 계수부호나 크기는 국가별로, 통화단위별로 상이하게 나타났다.

• 기술혁신연구
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• 제25권3호
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• pp.265-297
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• 2017

본 연구는 연구개발스톡과 6개의 지식스톡(특허의 질적 가치)이 기업의 시장가치에 미치는 영향을 포함하는 연구모형을 설정하여 기업의 시장가치와의 상관관계를 분석하였다. 구체적으로 토빈Q 모형을 사용하여 우리나라 402개 기업의 미국특허등록 108,851건(연도관측치 2,795건)의 특허를 분석하였다. Hall모형의 확장 모형 분석결과, 연구개발스톡/자산, 청구항스톡/특허스톡, 인용스톡/특허스톡 등이 기업의 시장가치에 긍정적인 영향을 미치는 것으로 나타났으며, 유의수준이 높진 않지만 피인용스톡/특허스톡, 발명자스톡/특허스톡 등도 기업의 시장가치에 긍정적인 영향을 미칠 수 있는 것으로 분석되었다. 이러한 결과에 따라 특허경영시대에 특허의 질적 수준 고도화와 특허의 가치 제고를 위한 정책 방안이 마련되어야 할 것으로 보인다.

• Journal of Animal Science and Technology
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• 제57권3호
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• pp.7.1-7.7
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• 2015

To meet the increasing demands of specific pathogen free (SPF) minipigs in biomedical researches, 8 pregnant Chinese Wuzhishan minipigs (WZSP) sows with clear background were chosen to obtain SPF WZSP by hysterectomy. At $111{\pm}days2$ of the pregnancy, piglets were aseptically taken out from the sows and artificially suckled for 40 to 45 days in the positive isolators. Then, the piglets defined as F0 were transferred to barrier environment and fed with standard feeds. The original SPF colony was formed for breeding by selected piglets from F0 group of 6-8 months old. Biological characteristics of SPF WZSP were collected and further compared to those of conventional (CV) WZSP, including growth performance, reproductive performance, hematology and blood biochemistry, and major pathogens detection. As a result, 61 F0 piglets were obtained from 8 candidate sows, and 55 out of them survived. After strictly selection, 35 F0 piglets were used to form the original SPF colony, which produced 14 litters of SPF piglets defined as F1. Piglet survival rates, growth performance, and reproductive performance of SPF WZSP were similar to CV WZSP. Some hematology and blood biochemistry parameters showed significant differences between SPF and CV WZSP. Eighteen kinds of pathogens were identified to be free in F0 and F1 SPF colony by repeated pathogen detections. In conclusion, we established a satisfied SPF WZSP colony maintaining original characteristics, free of controlled diseases, and being proved to be a suitable laboratory animal.

• 벤처혁신연구
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• 제1권2호
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• pp.47-59
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• 2018

최근 사회경제적 환경이 급격하게 변화하면서 기업은 고객 투자자들의 실체를 파악하기 위해서는 심리학, 경제학, 재무학을 기반으로 보다 현실적인 소비자행동의 틀을 제시해 줄 수 있어야 한다. 주식투자자들의 투자선택의 과정에서 사람들의 판단 및 평가가 다르게 나타나는 차이를 프레이밍 효과라고 하는데, 이것은 판단이나 선택에 관한 구성(decision frame)을 다르게 정의함으로써 투자자들의 투자에 대한 의사결정에 변화를 유발시킬 수 있다. 선행연구에서는 주식투자 관련 메시지프레이밍이 시장참여자들에게 어떤 영향을 미치는지, 그리고 특히 주식투자 메시지프레이밍에 따른 시장참여자들의 위험관리행동의 차이를 밝힌 연구는 매우 미흡하다. 따라서 본 연구는 투자자들이 선택적 의사결정을 하는데 있어서 주식투자 메시지프레이밍이 시장참여자들의 투자의도에 어떠한 영향을 주는지 그리고 이러한 메시지프레이밍 효과가 주식 투자 만족도 형성 원인에 조절효과가 있는지를 실증적으로 검증하고자 한다. 본 연구의 대상은 2018년 5월 1일 부터 5월 26일 까지 주식투자경험이 있는 494명을 설문조사하여 실증분석 자료로 이용하였다. 자료분석은 SPSS 24.0 통계분석 프로그램을 이용하였다. 본 연구의 결과는 다음과 같다. 첫째, 주식 투자 행동 요인 중, 주식 이해력과 주식에 대한 주변 추천, 주식 위험 정도는 주식 투자 만족도에 정(+)의 영향을 미치는 것으로 나타났으며, 주식 투자 행동 요인 중, 주식 이해력, 주식 브랜드, 주식에 대한 주변 추천, 과거 성과, 주식 위험 정도는 지속적 주식 투자의도에 정(+)의 영향을 미치는 것으로 나타났다. 둘째, 메시지프레이밍은 주식 투자 만족도에 유의한 영향을 미치는 것으로 나타났고, 메시지프레이밍은 주식 투자 행동과 주식 투자 만족도 관계에서 유의한 조절효과가 있는 것으로 분석되었다. 셋째, 메시지프레이밍은 지속적 주식 투자의도에 유의한 영향을 미치는 것으로 나타났고, 메시지프레이밍은 주식 투자 행동 요인과 지속적 주식 투자의도 관계에서 유의한 조절효과가 있는 것으로 분석되었다.

• 한국컴퓨터정보학회논문지
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• 제21권6호
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• pp.9-19
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• 2016

In finance literature, stock liquidity showing how stocks can be cashed out in the market has received rich attentions from both academicians and practitioners. The reasons are plenty. First, it is known that stock liquidity affects significantly asset pricing. Second, macroeconomic announcements influence liquidity in the stock market. Therefore, stock liquidity itself affects investors' decision and managers' decision as well. Though there exist a great deal of literature about stock liquidity in finance literature, it is quite clear that there are no studies attempting to investigate the stock liquidity issue as one of decision making problems. In finance literature, most of stock liquidity studies had dealt with limited views such as how much it influences stock price, which variables are associated with describing the stock liquidity significantly, etc. However, this paper posits that stock liquidity issue may become a serious decision-making problem, and then be handled by using data mining techniques to estimate its future extent with statistical validity. In this sense, we collected financial data set from a number of manufacturing companies listed in KRX (Korea Exchange) during the period of 2010 to 2013. The reason why we selected dataset from 2010 was to avoid the after-shocks of financial crisis that occurred in 2008. We used Fn-GuidPro system to gather total 5,700 financial data set. Stock liquidity measure was computed by the procedures proposed by Amihud (2002) which is known to show best metrics for showing relationship with daily return. We applied five data mining techniques (or classifiers) such as Bayesian network, support vector machine (SVM), decision tree, neural network, and ensemble method. Bayesian networks include GBN (General Bayesian Network), NBN (Naive BN), TAN (Tree Augmented NBN). Decision tree uses CART and C4.5. Regression result was used as a benchmarking performance. Ensemble method uses two types-integration of two classifiers, and three classifiers. Ensemble method is based on voting for the sake of integrating classifiers. Among the single classifiers, CART showed best performance with 48.2%, compared with 37.18% by regression. Among the ensemble methods, the result from integrating TAN, CART, and SVM was best with 49.25%. Through the additional analysis in individual industries, those relatively stabilized industries like electronic appliances, wholesale & retailing, woods, leather-bags-shoes showed better performance over 50%.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.377-383
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• 2011

The paper is to perceive accurately speed of the train through redundant processor operation. When Slip/slide is occurred at the axle, the train is applied brake force using the Tachometer and the Doppler sensor which assistance equipment. One of the main features of railway signaling system is that rolling stock is made stop to avoid collision with the rolling stock ahead when the rolling stock exceeds its maximum operating speed in line. In addition, in the case of the rolling stock with automatic train operation, it carries out activities such as braking and propulsion using the difference between its actual speed and target speed at the point. To perform these functions, it is essential to calculate the exact speed of the rolling stock in signaling equipment on vehicles. Train speed detection unit are composed of the Tachometer and the Doppler sensor, and speed information is sent to the SDU unit. The processor of SDU unit calculates the speed of the train using compare logic the received speed information. Even if there are Slip/Slide, signaling system is available to apply exact braking, to improve stop on position and to guarantee the safety of trains.