• Title/Summary/Keyword: DID 분석

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Nanoconfinement effects of MCM-41 on the thermal decomposition of metal borohydrides

  • Kim, Sanghoon;Song, Hyejin;Kim, Chul
    • Analytical Science and Technology
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    • v.31 no.1
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    • pp.1-6
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    • 2018
  • We used differential scanning calorimetry and a thermogravimetric analysis to investigate the effect of being confined in mesoporous MCM-41 on the decomposition of lithium borohydride and magnesium borohydride when heated. The confinement did not cause a phase transition of the metal borohydrides inside MCM-41, but did lower their decomposition temperature. With the exception of a lowering of the temperature, the decomposition reaction mechanism of the metal borohydrides was nearly the same for both the bulk and confined samples.

Study on Forms of Engel Curves in the Analysis of Household Budgets (가계분석에 있어서 Engel curvedml 함수형태에 관한 연구)

  • 배연수
    • Journal of the Korean Home Economics Association
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    • v.28 no.4
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    • pp.87-101
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    • 1990
  • This study was undertaken to test to fit forms of the Engel curves to data. The comparisons were confined to the linear, semi-logarithmic and double-logarithmic forms. Data from the 1970-1987 Urban Household Economy Survey were used to estimate the Engel curves. The twelve categories of consumption expenditure were considered for investigation. Parameters of the Engel curves were derived from OLS and TSLS. In this paper the size of the family was used as the deflater. The results could be summarized as follows: 1. Comparing with the R2 of three foms, it could be concluded that, the linear form generally gave a better fit to data than the other forms did. Only for housing and clothing and foot wear, did the semi-logarithmic form give a better fit. Only for meals outside the home, fuel, light and water charges, and miscellaneous, did the double-logarithmic form give a better fit. 2. Comping with the income elasticities based on the alternative forms, it could be concluded that the differences between the estimates were since each form made different assumption as to the way in which elasticity varied. In general, the semi-logarithmic form gave the highest estimate and double-logarithmic form did the lowest estimate. The difference between semi-logarithmic and the other forms were greater than the those of linear and double-logarithmic form. 3. It was found that the income elasticity varied with the difinition of income used as an explanatory variable in Engel curves.

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Evaluation of Accident Prevention Financial Support Projects in the Construction Industry Using DID and PSM (DID와 PSM 분석을 통한 건설업 클린사업장 대상 재정지원사업 평가)

  • Jang, Seong-Eun;Yu, Sung-Yeol;Kim, Hwa-Il
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.32 no.1
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    • pp.31-40
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    • 2022
  • Objectives: The purpose of this study is to understand the impact on accident reduction by analyzing the policy effectiveness of an industrial accident prevention clean workplace support project targeting the construction industry. Methods: In this study, DID and PSM models were used to analyze workplaces receiving and not receiving financial support based on the status of industrial accidents in recent years and the status of the workplaces by year. Results: The research results show that meaningful effects continued to occur in terms of reducing accidents and increasing employment. Conclusions: In this study, we show the effectiveness of the clean workplace support project, one of the South Korean government's financial support projects in the field of occupational safety and health focusing on the construction industry. Financial support projects such as clean projects should be further expanded based on the results of this study.

A Study on the Effect Analysis for the Regeneration Project for the Zones Vulnerable to Natural Disaster using Structural Equation Model (구조방정식 모형을 이용한 자연재해위험지구 정비사업 효과 분석)

  • Lee, Kyung Su;Jung, Jae Kwang;Heo, Bo Young;Byeon, Seong Joon
    • Journal of Korea Water Resources Association
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    • v.46 no.8
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    • pp.843-855
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    • 2013
  • In the modern society with high science and technological level, many people have been tried to mitigate natural disaster. The disaster was so huge that we made special service organization which deal with 'The Natural Disaster Endangered Districts'. But the analysis of the organization's works was inadequate. In order to analyze their regeneration project, this study selected analysis area and did a spot survey. We did validity, reliability tests and statistical data analysis of this survey. We also did reliability analysis of this policy using Structural Equation Model. According to the result, there is a reasonable suitability in 'The Natural Disaster Repair work Policy'. And it also improved spiritual, substantial environment of the surrounding people. The people formed positive awareness about Government Repairing Policy. This 'Natural Disaster Repair work Policy' is essential to improve and develop local community. Therefore it will affect democratic development of society.

Perfume Consumption Behaviors and Fragrance Sensibility Attitude according to Perfume Involvement Levels (향수 관여수준별 향수 소비행동 및 향기감성태도에 관한 연구)

  • Yoh, Eun-Ah
    • Journal of the Korean Society of Clothing and Textiles
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    • v.30 no.3 s.151
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    • pp.396-406
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    • 2006
  • This research explored perfume consumption behaviors and fragrance sensibility attitude according to perfume involvement level. Data were collected by surveying 241 female college students who are recognized as a core consumer group for perfume products in Korea. The collected data were analyzed through descriptive analysis, factor analysis, and t-test. In results, 241 respondents were classified into 2 groups with respect to perfume involvement. Group difference was found in some of consumption behaviors and fragrance sensibility attitude. Specifically, the high involvement group used more often and spent more money on perfume, than did the low involvement group. Also, people highly involved with perfume shopped more often in perfume specialty stores, considering smelling test as the more important information source than did people in the low involvement group. Young females most liked delightful and young sensibility of perfume fragrance while they disliked stimulating and strong fragrance. People in the high involvement group preferred sophisticated and modem feelings of perfume fragrance more than did people in the low involvement group. Based on results, product development and marketing implications were generated.

Characteristics of Bearing Capacity and Settlement According to the Difference of Loading Plate Sizes (재하판의 크기에 따른 지지력 및 침하특성)

  • 정형식;김도열
    • Journal of the Korean Geotechnical Society
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    • v.18 no.4
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    • pp.179-188
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    • 2002
  • The scale effect should be considered to determine the bearing capacity and settlement of footings from plate-load test, because of the size difference between a footing and a loading plate. To analyze characteristics of bearing capacity and settlement according to the difference of loading plate sizes, model tests were performed with four different sizes of square plate, which are B=10, 15, 20, and 25cm respectively, on five different kinds of subsoils. Test results showed that the ultimate bearing capacity of a footing on the sand did not increase proportional to the traditional formula and the bearing capacity on the clay also increased a little with increasing the size of loading plate. The settlement of test plate on the sand did not increase as the traditional formula of Terzaghi and Peck (1967), and the settlement on the clay also did not increase proportional to the traditional formula.

Analysis of Local Laws and Regulations Related to the Library (지방자치단체의 도서관 자치법규 분석)

  • Kim, Hong-Ryul
    • Journal of Korean Library and Information Science Society
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    • v.45 no.2
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    • pp.117-138
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    • 2014
  • This study was to investigate and analysis the library-related laws and regulations enacted by local governments. As a result, library regulations are investigated all 629 cases in nationwide survey. Among them, library-related ordinances are 393 cases, library-related regulations are 187 cases, and library-related anweisung are 43 cases, such as the order was followed. The Library ordinance 393 cases consist of library management ordinance(205 cases), small library ordinance(101 cases), reading promotion ordinance(49 cases), and so on. The 32 local governments did not enact the Library laws and regulations. And the 40 local government did not enact Library management ordinance. It is suggested that local government did not enact library-related laws should be established the library laws as soon as possible.

A Study on the Effect of Government Support on the Innovation of Defense Industry: Evidence from Korean firms (방위산업 혁신에 대한 정부지원 효과에 관한 연구: 우리나라 방산기업을 중심으로)

  • Kong, Hee-Jung;Bong, Kang Ho;Park, Jaemin
    • Journal of Digital Convergence
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    • v.18 no.1
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    • pp.1-10
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    • 2020
  • In this study, an empirical analysis using Difference-in-Difference(DID) methods was conducted based on the data of domestic defense companies to look at the impact of government support on the performance of these defense industries. As a result, we found that the volume of sales and assets of defense enterprises does not increase or decrease solely on the benefit of government support. In addition, government support for net profit to total sales ratio and net profit to total assets ratio improved significantly, but the effect was only seen in the short term. Unlike previous studies that focused on identifying the existence of differences between industries, our research is different in that it is the first to analyze empirically within the Korean defense industry. It is also theoretically meaningful in that it looked at the effects of government support, especially in industries with unique characteristics that have yet to be known.

Analysis of the Firm Support Effects of the Innovation Procurement Policy Using Propensity Score Matching and Difference in Differences (성향점수매칭(PSM)-이중차분(DID) 결합모형을 이용한 혁신조달 정책의 기업지원 효과 분석)

  • Juwon Kim;Wonik Park
    • Journal of Technology Innovation
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    • v.31 no.3
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    • pp.201-230
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    • 2023
  • The Innovation Procurement Policy was introduced as part of the strategic public procurement policy to improve firms' innovation capabilities and enhance the public sector's ability to solve social problems by designating and purchasing so-called 'innovative products.' The pilot procurement project for innovative products was first introduced in 2019, and the policy system for designating and discovering innovative products by government departments, as well as the priority purchase system, was established in 2020. Hence, this study conducted a quantitative analysis focusing on the effectiveness of the innovation procurement system in supporting firms after it was fully implemented. For this purpose, corporate financial and employment data from 2017 to 2021 were used, and propensity score matching(PSM) and difference-in-difference(DID) methods were utilized as analytical tools. The study found that the innovation procurement system contributed to corporate growth and employment and created additional public and private sales channels. Moreover, it is necessary to enhance the innovation procurement system, such as matching innovative product-producing companies with existing SME support policies, for companies to become self-sustaining after the innovative product designation ends.

Characterization of Fly Ash Produced from a Sewage Sludge Incineration Facility in Korea (국내 하수슬러지 소각시설에서 발생되는 비산재의 특성 분석)

  • Kim, Seong-beom;Lee, Wontae
    • Journal of Korean Society of Environmental Engineers
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    • v.38 no.2
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    • pp.96-99
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    • 2016
  • This study characterized fly ash produced from a sewage sludge incineration facility in Korea to determine if the byproducts can be utilized. All the incinerated sewage sludge was from a city in Korea. To characterize fly ash and to determine if it can be utilized, pH, water contents, elemental components, particle size, surface morphology, heavy metal compositions, and others were analyzed. In average, pH was 6.2, and water contents was about 5%. T-N and $T-P_2O_5$ were 3% and 24.5%, respectively. Particle size averaged 836 nm; surface morphology did not exhibit any significant results. X-ray diffraction (XRD) analysis results revealed that major components of the fly ash were $P_2O_5$, CaO, MgO, $K_2O$. Composition of heavy metals by the Korea Standard Methods for Waste Quality did not exceed the criteria for specified wastes in Korea.