• Title/Summary/Keyword: r-value

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Effect of Carbon on Microstructure and Texture in Low Carbon Steels (저탄소강의 미세조직과 집합조직에 대한 탄소의 영향)

  • Jeong, Woo Chang
    • Journal of the Korean Society for Heat Treatment
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    • v.27 no.2
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    • pp.79-89
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    • 2014
  • The effect of carbon on the microstructure and texture of low carbon steels was investigated in a series of 1.6 Mn-0.3Cr-0.2Mo-0.001B steels with carbon ranging from 0.021 to 0.048%. Intensity of {111} orientation increased with decreasing the carbon content, resulting in the increase in $r_m$ value. The highest $r_m$ value of 1.30 was obtained in 0.021%C steel annealed at $820{\sim}850^{\circ}C$ according to the typical galvannealing heat cycle. Martensite volume fraction was not substantially affected by the annealing temperature. It was found that the fine and uniformly distributed martensite particles which were present in amounts of about 5% volume fraction were desirable for the highest $r_m$ value. The other factor affecting the high $r_m$ value was the preferred epitaxial growth of retained ferrite with {111} orientation into austenite during cooling.

Comparison of Dimension Reduction Methods for Time Series Factor Analysis: A Case Study (Value at Risk의 사후검증을 통한 다변량 시계열자료의 차원축소 방법의 비교: 사례분석)

  • Lee, Dae-Su;Song, Seong-Joo
    • The Korean Journal of Applied Statistics
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    • v.24 no.4
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    • pp.597-607
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    • 2011
  • Value at Risk(VaR) is being widely used as a simple tool for measuring financial risk. Although VaR has a few weak points, it is used as a basic risk measure due to its simplicity and easiness of understanding. However, it becomes very difficult to estimate the volatility of the portfolio (essential to compute its VaR) when the number of assets in the portfolio is large. In this case, we can consider the application of a dimension reduction technique; however, the ordinary factor analysis cannot be applied directly to financial data due to autocorrelation. In this paper, we suggest a dimension reduction method that uses the time-series factor analysis and DCC(Dynamic Conditional Correlation) GARCH model. We also compare the method using time-series factor analysis with the existing method using ordinary factor analysis by backtesting the VaR of real data from the Korean stock market.

Factors Influencing the Customer Value and the Performance of National R&D Information Services of the R&D Managers (연구관리자의 국가R&D정보서비스 고객가치 및 업무성과 영향요인)

  • Suh, Sang-Hyuk;Lee, Sun-Young;Lee, Byeong-Hee
    • The Journal of the Korea Contents Association
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    • v.14 no.7
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    • pp.480-494
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    • 2014
  • The importance of knowledge and information is ever increasing. The ingredients of the customer value of the information offered for free by the public information organizations are different from those of the ordinary products or services. This study aims to identify the factors which affect the information customer value and the job performance of the R&D managers who use national R&D information service(NTIS). The results show the quality of information service and the perception of services organizations have significant positive effect on customer value. In addition, the customer value have significant influence on the job performance. Meanwhile, the perception of information organizations have not effect on the job performance. Regarding the moderating effect of the information using environment, the results are as follows: the information using environment moderates the relationship between the information service quality and between the customer value and the perception of information organizations, and the relationship between the customer value and the job performance, but does not moderate the relationship between the perception of information services organizations and the job performance. According to the research results, we proposed several implications to foster the customer value management in the field of public information as well as future research directions.

The Effects of R&D Expenses and patents on the Firm value (특허권과 연구개발비 지출이 기업가치에 미치는 영향)

  • Oh, Sang-Hui
    • Management & Information Systems Review
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    • v.36 no.3
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    • pp.239-254
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    • 2017
  • This study examines the relationship between R&D spending and patent rights, which are suggested by firms as a way to increase their firm value. Specifically, we examine the relationship between research and development costs and patent rights, and see if there are any differences in the influence of two variables on firm value. The period of this study is from 2005 to 2016, and the sample of companies used in the research including the patenting companies is composed of 333 companies in total. The results of the study are as follows. First, the cost of R&D expenditure and capitalized R&D expenditure showed a significant positive correlation with patents. Second, R&D spending did not show a significant relationship with firm value, but patent rights showed a significant positive correlation with firm value. However, firms that spend a large amount of R&D expenditure (RDD), such as research and development expenses, showed a significant positive (+) value and a patent dummy (PATD). Third, in the analysis of the difference between the dummy of research and development and the patent dummy, the enterprise value of a company that invested a lot of patents and research and development expenses was high. The contribution of this study is to examine the relevance of corporate value to R&D investment for patents. On the other hand, there are various variables that can be used as a sample of patents.

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Evaluation of the Economic Values and Optimal Deployment Timing of R&D Investment in New and Renewable Energy Using Real Option Approach (실물옵션을 이용한 신재생에너지 R&D의 경제적 가치 및 최적 적용시점 평가)

  • Kim, Kyung-Taek;Lee, Deok-Joo;Park, Sung-Joon
    • Journal of Korean Institute of Industrial Engineers
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    • v.38 no.2
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    • pp.144-156
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    • 2012
  • In recent years, advanced countries in energy sector are emphasizing the importance of the development and deployment of renewable energy to cope with the global environmental crisis such as depletion of fossil energy, climate convention to control emissions of greenhouse gases. In this paper, we evaluate the economic value of the investment in new and renewable energy R&D in Korea and optimal deployment timing of new and renewable energy by using the real option approach. The real option model adopted in this paper assumes that a decision maker has a compound option to abandon, deployment, or continue the R&D. As a result by using empirical data of Korea, it is found that there exists a considerable amount of positive real option value (ROV) in the investment of new and renewable energy R&D while its net present value (NPV) calculated by traditional discounted cash flow (DCF) model shows negative value.

Effects of Storage Temperature and Packaging Methods on the Physicochemicl Quality of Boiled-Dried Anchovies (저장온도 및 포장조건이 건멸치의 이화학적 품질에 미치는 영향)

  • 권중호;정형욱;변명우;김정숙
    • Journal of Food Hygiene and Safety
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    • v.10 no.2
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    • pp.97-102
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    • 1995
  • For improved preservation of boiled-dried anchovies, the current preservation method of corrugated-cardboard box packaging and freezing below -18$^{\circ}C$ was compared to the nylon/polyethylene(NY/PE) packaging along with cooling temperature ranging from 5$^{\circ}C$ to 1$0^{\circ}C$ as well as ambient condition for eight months by determining physicochemical quality of stored samples. Lipid oxidation of stored anchovies and their browning increased with storage time. The phenomenon was delayed under the conditions of lower temperature and air-tight packaging. As quality-indicative criteria of stored anchovies, carbonyl value(r=-0.989), browning (r=-0.949) and color a value(r=-0.989), browning(r=-0.965), Hunter's color b value(r=-0.949) and color a value(r=-0.940) showed a highly-negative correlations with organoleptic qualities of the samples. Based on the above results, air-tight packaging in a laminated film and subsequent storage at cooling temperature was found to be a possible alternative to the current freezing-storage of boiled-dried anchovies from the physicochemical point of view.

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The Development of Terminal for Long Distance Data Transmission Using UHF RFID Module (UHF RFID 모듈을 이용한 원거리 데이터 전송 전용단말기 개발)

  • Hwang, Gi-Hyun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.11
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    • pp.2465-2472
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    • 2009
  • This research paper is to develop remote data transmission terminal which is adequate to RFID R/W by using UHF/RF RFID R/W module (WJR7090) and Bluetooth communication(FB755AC) with ARM chipset(AT91SAM7S256). The developed UHF RFID R/W terminal performs tagging of RPID value and transmit the value to server with Bluetooth communication, the transmitted RFID tag value is compared to the Database value and the result is transmitted to the terminal. Performance test was done in order to prove the performance of the terminal, and the test result of the terminal's excellency and transmitted/recevied packet is described.

On Value-driven Market Orientation Strategies in Academic Libraries (대학도서관의 가치 기반 서비스 마케팅 강화 전략)

  • Shim, Won-Sik
    • Journal of Korean Library and Information Science Society
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    • v.38 no.3
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    • pp.321-334
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    • 2007
  • Marketing techniques developed for private organizations are being widely used in libraries. The primary focus in marketing has shifted to maximizing user perceived value from the perspective of library users. This paper examines library as an industry as a way to establish the basis for library's overall value, applies the R-I-R model and its taxonomy of value in using library and information services, and proposes market orientation approach to systematically plan and coordinate academic library marketing activities.

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A study on consistency and accuracy of pulse diagnosis in Eight-Constitution Medicine

  • Shin, Yong-Sup;Nah, Seong-Su;Oh, Hwan-Sup;Park, Young-Jae;Park, Young-Bae
    • Advances in Traditional Medicine
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    • v.9 no.1
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    • pp.14-19
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    • 2009
  • The aim of this study is to evaluate appraiser's consistency and accuracy about pulse diagnosis (PD) in discrimination of eight-constitutions using Gage R&R study. Cumulative numbers of PD for discrimination of eight constitutions of three appraisers' experience were 75,000 cases, 50,000 cases, 1,100 cases, respectively. Three Appraisers diagnosed subject's eight-constitutions by PD with blinded method. Gage R&R study was used to verify the results. In the measurements of consistency, appraiser B (agreement = 80%, Value of k = 0.8276) was very good, appraiser A (agreement = 70%, Value of k = 0.7465) was good, and appraiser C (agreement = 50%, Value of k = 0.5365) was moderate. In the measurements of accuracy, appraiser B (agreement = 70%, Value of k = 0.6812) was good, appraiser A (agreement = 60%, Value of k = 0.6414) was good, and appraiser C (agreement = 0%, Value of k = -0.1000) was poor. The results suggest that accuracy of discrimination of constitutions relatively depend on experience and number of cases of PD. Further large controlled study is needed to evaluate the accuracy of PD.

Posttraumatic Stress in Fire fighters (소방대원의 외상후 스트레스 실태)

  • Koh, Bong-Yeun
    • The Korean Journal of Emergency Medical Services
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    • v.12 no.3
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    • pp.5-15
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    • 2008
  • Purpose : This study is a descriptive research to provide basic factors of posttraumatic stress in Firefighters. This study was carried out to develop the effective program for the fire fighters to cope with the posttraumatic stress following the disasters. Methods : The questionnaires were collected among fire fighters who serviced in K and I community from April 1 to June 30 in 2008. Total 304 questionnaires were analyzed by SPSS WIN program for descriptive statistics, Pearson's correlation coefficient and t-test. Results : 1. 48.0% of 300 fire fighters were at the age of 31-40, and 42.3% were under 30. 2. Work burden had a significant difference of 2.30 in low-risk group, 2.60 in high-risk group(t-value=-3.85, p=0.00). However, life event had no significant difference 0.79 event in low-risk group, 1.41 event in high-risk group(t-value=-2.27, p=0.24). 3. Concerning posttraumatic stress factors, there was positive correlation between mobilization impact level r=0.38(P<0.01), work burden r=0.38(p<0.01), and life event r=0.27(p<0.01). 4. According to the Symptom Check List-Revised(SCL-90-R), somatization had a significant differences(t-value=5.46, p=0.00), obsessive-compulsive(t-value=7.16, p=0.00), interpersonal sensitivity(t-value=6.15, p=0.00), depression(t-value=6.62, p=0.00), anxiety (t-value=7.33, p=0.00), hostility(t-value=5.94, p=0.00), phobia anxiety(t-value=6.85, p=0.00), paranoid ideation(t-value=5.55, p=0.00), psychotism(t-value=6.52, p=0.00) in low-risk and high-risk group. Conclusion : As a consequence, mobilization impact, work burden, and life event were the influential factors on posttraumatic stress. Also, high-risk group revealed significantly higher score on all 9 scales. The information obtained from surveys made recommendation to develop the intervention of stress management to control mobilization impact and posttraumatic stress.

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