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Economic Efficiency of the BAT Standards in a Multi-pollutant Environment (다오염물질 상황에서의 최적가용기법 기준의 경제적 효율성에 관한 연구)

  • Han, Taek-Whan;Lim, Dongsoon
    • Journal of Environmental Impact Assessment
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    • v.28 no.2
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    • pp.141-151
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    • 2019
  • Korea has passed the Act on the Integrated Control of Pollutant-Discharging Facilities in 2015, and the integrated environmental management under the BAT standard is underway. To summarize the nature of integrated environmental management, it is the regulation by the integration of the management of the multi-pollutant source and the technical standard of BATs. In general, in environmental economics, regulation-based on technical standards are known to be inefficient. This paper attempts to evaluate the efficiency of BAT standards from an economic point of view. A simple multi-pollutant model demonstrates that the inefficiency of the environmental tax with imperfect information in a single pollutant situation is amplified under multi-pollutant conditions. The simultaneous introduction of BAT and IPPC can be partially explained by this logic. It is also highlighted by the strengthening of BAT standards by EU, as a countermeasure to the potential deterioration of air quality caused by the change of effective environmental taxes accompanying the fuel and emission price changes.

The Impact of Exclusive Subcontracting on the Input, Behavior and Output of Innovation in Small Venture Firms: Evidence from Manufacturing Industries of Korea (수·위탁거래의 전속성이 중소벤처기업의 혁신 투입, 활동 및 성과에 미치는 영향)

  • Kim, KonShik
    • Journal of Korea Technology Innovation Society
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    • v.22 no.3
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    • pp.382-415
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    • 2019
  • This study analyzes the impact of exclusive subcontracting on the input, behavior, and output of innovation in manufacturing industries of Korea. Based on the analysis of pooled cross-sectional data of 6,029 small venture firms, this study proved that the exclusive subcontracting between small venture firms and large enterprises are lowering R&D investment of small venture firms. Second, the innovation activities of small venture firms including the ratio of R&D personnel and the scope of cooperation and partnership with external organizations were lower than those of small venture firms that have non-exclusive or no relations with large enterprises. Third, the innovation performance of small venture firms such as the number of patent applications, the ratio of sales by new products, and the cumulative sales growth rate was lower than those of small venture firms that have non-exclusive or no relations with large enterprises. This study verifies that the exclusive subcontracting relationships significantly weaken the innovation process and performance of small venture firms systematically, resulting in a kind of market failure in which small venture firms have almost no incentive to facilitate innovation.

The Validity of Activity Participation Assessment for School-Age Children (학령기 아동을 위한 활동 참여 평가도구(Activity Participation Assessment)의 타당도 연구)

  • Kim, Se-Yun
    • The Journal of Korean Academy of Sensory Integration
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    • v.17 no.1
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    • pp.19-29
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    • 2019
  • Objective : The aim of this study was to verify validity of the Activity Participation Assessment for school-age children. Methods : A questionnaire consisting of 30 items from the APA, 75 items from the PACS, and 55 items from the CAPE was administered to elementary school students. A total of 207 questionnaires were analyzed. Confirmatory factor analysis was performed to confirm the construct validity of the APA. Convergence validity and discriminant validity were verified with the average variance extracted (AVE) and the square of the correlation coefficient. The discriminant validity was the Pearson correlation coefficient of the APA, PACS, and CAPE. Results : The results of the analysis were as follows: 1) For construct validity, the goodness of fit of the modified hierarchical second-order factor model was found to be appropriate (p < .001), 2) For convergent validity, the AVE was higher than .50 for all latent variables, 3) For discriminant validity, the AVE of the latent variable was greater than the square of the correlation coefficient (0.239), 4) For concurrent validity, the correlation between the total sum of the APA and PACS scores showed a positive correlation in all domains, and the correlation coefficient ranged from .303 to .647 at a statistically significant level (p < .01), 5) The correlation coefficient between the total sum of the APA and CAPE scores was .490 for recreational activities, .329 for physical activities, .571 for social activities, .401 for skill-based activities, and .390 for self-improvement activities. All domains showed a positive correlation, and were statistically significant (p < .01). Conclusion : APA can be used as a valid assessment tool to measure the participation of school aged children.

A Study on the Element Technologies in Flame Arrester of End Line (선박의 엔드라인 폭연방지기의 요소기술에 관한 연구)

  • Pham, Minh-Ngoc;Choi, Min-Seon;Kim, Bu-Gi
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.25 no.4
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    • pp.468-475
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    • 2019
  • An end-line flame arrester allows free venting in combination with flame protection for vertical vent applications. End-line flame arresters are employed in various fields, especially in shipping. In flame arresters, springs are essential parts because the spring load and the spring's elasticity determine the hood opening moment. In addition, the spring has to work under a high-temperature condition because of the burning gas flame. Therefore, it is necessary to analyze the mechanical load and elasticity of the spring when the flame starts to appear. Based on simulations of the working process of a specific end-line flame arrester, a thermal and structural analysis of the spring is performed. A three-dimensional model of a burned spring is built using computational fluid dynamics (CFD) simulation. Results of the CFD analysis are input into a finite element method simulation to analyze the spring structure. The research team focused on three cases of spring loads: 43, 93, and 56 kg, correspondingly, at 150 mm of spring deflection. Consequently, the spring load was reduced by 10 kg after 5 min under a $1,000^{\circ}C$ heat condition. The simulation results can be used to predict and estimate the spring's load and elasticity at the burning time variation. Moreover, the obtained outcome can provide the industry with references to optimize the design of the spring as well as that of the flame arrester.

A Study on the Improvement of the Education and Training System for Response to Marine Chemical Incidents in Korea - Based on the Comparison of Systems between Korea and Foreign Countries - (해상화학사고 대응을 위한 국내 교육훈련체계 개선에 관한 연구 - 국내 체계와 외국 체계의 비교를 기반으로 -)

  • Kim, Kwang-Soo;Lee, Moonjin
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.23 no.7
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    • pp.847-857
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    • 2017
  • The present situations of the education and training systems for the response to marine HNS spill incidents in domestic and foreign countries were reviewed and the plans to improve domestic system were suggested on the basis of the comparison between domestic and foreign education systems. There were almost no private education and training institutions in Korea, and they have not been activated, compared with those of foreign countries such as USA, Canada, Australia and UK. The domestic marine HNS-related education has been implemented uniformly under Korean government initiative. In addition, there were differences in the targets and duration of the education offered by Korea Coast Guard Academy (KCGA) and Marine Environment Research & Training Institute (MERTI) in Korea. Domestic HNS-related curriculum was relatively simple, compared with the curricula of foreign countries, and has not accepted two levels (operational level and manager level) required in HNS model courses of International Maritime Organization (IMO). The domestic education and training period was short relatively to those of foreign countries. The following suggestions were made to improve the education and training system for the response to domestic marine chemical incidents. In the short term, an HNS education and training management consultation body (tentative name) should be established, with both KCGA and MERTI participating jointly while maintaining the current system of the two institutions (KCGA and MERTI) simultaneously. In the more distant and long term, the HNS-related departments of KCGA and MERTI should be incorporated into a National Marine HNS Response Academy (tentative name) as unified system to enable international competitiveness.

The Effects of Educational Context Variables on Achievement and Interest in Mathematics in High and Low Achieving Students (수학 성취와 흥미에 영향을 주는 변인의 성취 집단별 차이)

  • Choi, Ji Sun;Sang, Kyongah
    • Journal of the Korean School Mathematics Society
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    • v.22 no.2
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    • pp.163-182
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    • 2019
  • The purpose of this study is to investigate the effects of educational context variables on achievement and interest in mathematics in high and low achieving students in Korea. Students participated in TIMSS 2015 in Korea were divided into two groups according to their achievement in mathematics. And the effects of educational context variables on achievement and interest in mathematics were analyzed in each group using the Hierarchical Linear Model(HLM). Main findings of this study are as follows. First, variables which influence achievement also influence interest but any variables which influence interest don't influence achievement in upper-group students. Number of Books and Students' Perceived Mathematics Lessons have strong influence on achievement and interest in both fourth and eighth grade students. Second, variables which influence achievement or interest in mathematics in lower-group also influence achievement or interest in mathematics in upper-group students. But any variables which influence achievement or interest in upper-group students don't influence achievement or interest in lower-group students. For examples, Parents' Education, Students' Perceived Mathematics Lessons have effects on upper-group students' achievement. Number of Books, Home Learning Environment, and Numeracy Activities Before School have significant effects on the achievement of fourth grade students. Students' Perceived Mathematics Lessons is the variable that influence on the interest of both fourth grade and eighth grade students. This study suggests the ways to improve mathematics teaching and learning based on these results.

Awareness regarding Safe Abortion among Adolescent Girls in Rural area of Mahottari district of Nepal

  • Singh, Jitendra Kumar;Sah, Poonam Kumari;Kushwaha, Shambhu Prasad;Bajgain, Bishnu Bahadur;Chaudhary, Sanjay
    • Journal of agricultural medicine and community health
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    • v.44 no.2
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    • pp.73-81
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    • 2019
  • This study aimed to assess the level of awareness on safe abortion among adolescent girls in rural area of Mahottari district of Nepal. A community based cross-sectional study was conducted in rural areas of Mahottari district of Southern Nepal between January and March 2019.A sample of 412 adolescent girls was selected using multi-stage cluster sampling. Multivariable logistic regression model was adapted to explore level of awareness among adolescent girls. This study found that 45.6% of adolescent girls had high awareness regarding safe abortion. The odds of awareness among the married adolescents was higher (AOR=2.16; 95% CI: 1.01-4.87) than unmarried adolescent whereas the odds of awareness among the adolescents who had education of secondary level and more had higher (AOR=2.21; 95%CI: 1.13-3.04) than those who had primary or lower secondary level of education. Similarly, the adolescents who had monthly family income of Nepalese Rupees (NRs.), 10,000-20,000 and more than NRs. 20,000 were respectively, 2.33 times (AOR = 2.33; 95% CI: 1.07-3.55) and 3.17 times (AOR = 3.17; 95% CI: 2.19-8.94) more likelihood to have high awareness regarding safe abortion than those their counterparts. The study showed that overall level of knowledge towards safe abortion was found low. Socio-demographic factors like marital status, level of education, and family income were the factors independently associated with level of awareness on safe abortion. Therefore, efforts should be exerted towards arising and improving the awareness of abortion care which may reduce unwanted pregnancy, abortion and other complications related to abortion.

Proposal and Analysis of Primality and Safe Primality test using Sieve of Euler (오일러체를 적용한 소수와 안전소수의 생성법 제안과 분석)

  • Jo, Hosung;Lee, Jiho;Park, Heejin
    • Journal of IKEEE
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    • v.23 no.2
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    • pp.438-447
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    • 2019
  • As the IoT-based hyper-connected society grows, public-key cryptosystem such as RSA is frequently used for encryption, authentication, and digital signature. Public-key cryptosystem use very large (safe) prime numbers to ensure security against malicious attacks. Even though the performance of the device has greatly improved, the generation of a large (safe)prime is time-consuming or memory-intensive. In this paper, we propose ET-MR and ET-MR-MR using Euler sieve so it runs faster while using less memory. We present a running time prediction model by probabilistic analysis and compare time and memory of our method with conventional methods. Experimental results show that the difference between the expected running time and the measured running time is less than 4%. In addition, the fastest running time of ET-MR is 36% faster than that of TD-MR, 8.5% faster than that of DT-MR and the fastest running time of ET-MR-MR is 65.3% faster than that of TD-MR-MR and similar to that of DT-MR-MR. When k=12,381, the memory usage of ET-MR is 2.7 times more than that of DT-MR but 98.5% less than that of TD-MR and when k=65,536, the memory usage of ET-MR-MR is 98.48% less than that of TD-MR-MR and 92.8% less than that of DT-MR-MR.

Effect of Different Variable Selection and Estimation Methods on Performance of Fault Diagnosis (이상진단 성능에 미치는 변수선택과 추정방법의 영향)

  • Cho, Hyun-Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.9
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    • pp.551-557
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    • 2019
  • Diagnosis of abnormal faults is essential for producing high quality products. The role of real-time diagnosis is quite increasing in the batch processes of producing high value-added products such as semiconductors, pharmaceuticals, and so forth. In this study, we evaluate the effect of variable selection and future-value estimation techniques on the performance of the diagnosis system, which is based on nonlinear classification and measurement data. The diagnostic performance can be improved by selecting only the variables that are important and have high contribution for diagnosis. Thus, the diagnostic performance of several variable selection techniques is compared and evaluated. In addition, missing data of a new batch, called future observations, should be estimated because the full data of a new batch is not available before the end of the cycle. In this work the use of different estimation techniques is analyzed. A case study on the polyvinyl chloride batch process was carried out so that optimal variable selection and estimation methods were obtained: maximum 21.9% and 13.3% improvement by variable selection and maximum 25.8% and 15.2% improvement by estimation methods.

The Effect of Person-Job Fit on Job Satisfaction for the Employees of the Service Sector: Focused on the Mediating Effects of Perceived Organizational Support (서비스직 근로자의 개인-직무 적합성과 직무만족 관계에서 조직후원인식의 매개효과 분석)

  • Jang, Sunyun;Song, Ji Hoon;Kim, Soo Jung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.9
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    • pp.111-120
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    • 2019
  • This study examined the mediating effects of perceived organizational support (POS) on the relationship between the person-job fit and job satisfaction of service workers. POS is divided into socioemotional POS and instrumental POS. To achieve the research purpose, a questionnaire survey was conducted on workers in charge of service jobs in domestic companies through an on-line survey system and finally, the results of 281 respondents were analyzed to verify the hypothesized research model with an 80.3% effective recovery rate. The findings are as follows. First, the person-job fit has positive effects on job satisfaction and POS. Second, among the sub-constructs of POS, socioemotional support has mediating effects, but instrumental support has no mediating effects on the relationship between person-job fit and job satisfaction. Based on the results of this study, this study suggests theoretical and practical implications for the human resource development and management of service workers. Overall, changes in the recruitment system, which can judge the person-job fit of employees who perform emotional labor facing customers, organizational culture and personnel system for establishing socioemotional support system, and compensation and workforce development system, are needed to enhance the job satisfaction of service workers.