• Title/Summary/Keyword: Factor of Safety

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Quantitative Microbial Risk Assessment Model for Staphylococcus aureus in Kimbab (김밥에서의 Staphylococcus aureus에 대한 정량적 미생물위해평가 모델 개발)

  • Bahk, Gyung-Jin;Oh, Deog-Hwan;Ha, Sang-Do;Park, Ki-Hwan;Joung, Myung-Sub;Chun, Suk-Jo;Park, Jong-Seok;Woo, Gun-Jo;Hong, Chong-Hae
    • Korean Journal of Food Science and Technology
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    • v.37 no.3
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    • pp.484-491
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    • 2005
  • Quantitative microbial risk assessment (QMRA) analyzes potential hazard of microorganisms on public health and offers structured approach to assess risks associated with microorganisms in foods. This paper addresses specific risk management questions associated with Staphylococcus aureus in kimbab and improvement and dissemination of QMRA methodology, QMRA model was developed by constructing four nodes from retail to table pathway. Predictive microbial growth model and survey data were combined with probabilistic modeling to simulate levels of S. aureus in kimbab at time of consumption, Due to lack of dose-response models, final level of S. aureus in kimbeb was used as proxy for potential hazard level, based on which possibility of contamination over this level and consumption level of S. aureus through kimbab were estimated as 30.7% and 3.67 log cfu/g, respectively. Regression sensitivity results showed time-temperature during storage at selling was the most significant factor. These results suggested temperature control under $10^{\circ}C$ was critical control point for kimbab production to prevent growth of S. aureus and showed QMRA was useful for evaluation of factors influencing potential risk and could be applied directly to risk management.

A Study on Global Initiatives on Greenhouse Gas Reduction in the International Aviation (항공분야 기후변화 대응 현황 - 최근 ICAO 고위급회의 논의를 중심으로 -)

  • Maeng, Sung-Gyu;Hwang, Ho-Won
    • The Korean Journal of Air & Space Law and Policy
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    • v.24 no.2
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    • pp.47-67
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    • 2009
  • In recent years, greenhouse gas (GHG) reduction has become high priority issue in international aviation. GHG emissions from the aviation sector only accounts for approximately 2 percent of total GHG emissions in the world. However, as with GHG gases in other sectors, it has been pointed out as a contributing factor to global warming and there is an ongoing conversation in the aviation community to establish international framework for emissions reductions. In the case of international aviation, effects of aviation activities of a State go beyond the airports and airspace of that State. This makes compiling of GHG emissions data very difficult. There are also other legal and technical issues, namely the principle of “Common but Differentiated Responsibility (CBDR)” under the United Nations Framework Convention on Climate Change (UNFCCC) and “Fair Opportunity” principle of the Chicago Convention. For all these reason, it is expected that it will not be an easy job to establish an internationally agreed mechanism for reducing emissions in spite of continuing collaboration among States. UN adopted the UNFCCC in 1990 and the Kyoto Protocol in 1997 to impose common but differentiated responsibility on emissions reductions. In international aviation, ICAO has been taking the lead in measures for the aviation sector. In this role, ICAO held the High-level Meeting on International Aviation and Climate Change on 7 to 9 October 2009 at its Headquarters in Montreal and endorsed recommendations on reducing GHG from international aviation which will also be reported to the 15th Meeting of the Conference of the Parties (COP15). Key items include basic principle in global aviation emissions reduction: aspirational goals and implementation options: strategies and measures to achieve goals: means to measure and monitor the implementation; and financial and human resources. It is very likely that the Republic of Korea will be included among the Parties subject to mandatory limitation or reduction of GHG emissions after 2013. Therefore, it is necessary for Korea to thoroughly analyze ICAO measures to develop comprehensive measures for reducing aviation emissions and to take proactive actions to prepare for future discussions on critical issues after COP15.

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Assessment of the Cause and Pathway of Contamination and Sustainability in an Abandoned Mine (폐광산 오염원인 분석 및 오염경로, 향후 지속가능성에 대한 평가)

  • Kim, Min Gyu;Kim, Ki-Joon;Jeong, Gyo-Cheol
    • The Journal of Engineering Geology
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    • v.28 no.3
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    • pp.411-429
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    • 2018
  • Daeyoung mine (also called "Daema mine") produced gold and silver from mainly gold- and silver-bearing quartz veins. The mine tailings are a waste hazard, but most of the tailings were swept away or dispersed throughout the area around the mine long before the tailing dump areas were transformed into agricultural land. Soil liner and protection facilities, such as retaining walls, were constructed in the mine area to prevent the loss of tailings. The content of the tailings is 3,424.41~3,803.61 mg/kg, which exceeds the safety standard by a factor of 45. In addition, contamination was detected near agricultural areas and in the sediments in downstream drainage channels. A high level of As contamination was concentrated near the waste tailings yard; comparaable levels were detected in agricultural areas close to streams that ran through the waste dump yard, whereas the levels were much lower in areas far from the streams. The contamination in stream sediments showed a gradual decrease with distance from the mine waste yard. Based on these contamination patterns, we concluded that there are two main paths that affect the spread of contaminants: (1) loss of mine waste, and (2) the introduction of mine waste into agricultural areas by floods after transportation by streams. The agricultural areas contaminated by mass inflow of mine waste can act as contamination sources themselves, affecting other agricultural areas through the diffusion of contaminants. At present, although the measured effect in minimal, sediments in streams are contaminated by exposed mine waste and surface liners. It is possible for contaminants to diffuse or spread into nearby areas if heavy elements trapped in soil grains in contaminated agricultural areas leach out as soil solution or contaminant particles during diffusion into the water supply.

A pilot study of neuroprotection with umbilical cord blood cell transplantation for preterm very low birth weight infants (극소 저 출생체중 미숙아에서 자가 제대혈 줄기세포 이식을 통한 신경 손상 방지 연구)

  • Chae, Kyu Young;Lee, Kyu Hyung;Eun, So Hee;Choi, Byung Min;Eun, Baik-Lin;Kang, Hoon-Chul;Chey, Myung Jae;Kim, Nam Keun;Oh, Doyeun
    • Clinical and Experimental Pediatrics
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    • v.50 no.9
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    • pp.882-890
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    • 2007
  • Purpose : Preterm very low birth weight infant have high rate of adverse neurodevelopmental sequale. Recently, there have been lots of reports that human umbilical cord blood transplantation ameliorates functional deficits in animal models as hypoxic ischemic injury. This pilot study was undertaken to determine the clinical efficacy and safety of autologous umbilical cord blood cell transplantation for preventing neurodevelopmental sequale in perterm VLBW. Methods : Subjects were 26 preterm infants whose birth weight are less than 1,500 g and delivered under the intrauterine period 34 weeks. Autologous umbilical mononuclear cells (about $5.87{\times}10^7/kg$) were injected to neonate via the umbilical vein on the postnatal 24-48 hour. The therapeutic efficacy was assessed by numbers of nucleated RBC, urinary uric acid/creatinine ratio, concentration of neuron specific enolase (NSE), interleukin 6 (IL6), interleukin-$1{\beta}$ ($IL-1{\beta}$), and glial cell derived neurotrophic factor (GDNF) in serum and cerebrospinal fluid on day 1 and 7. Results : There were no significant differences in the numbers of the nucleated RBC, urinary uric acid/creatinine ratio, concentration of creatine kinase between the transplanted infants and controls. But the nucleated RBC is more likely to be rapidly discharged in the transplanted group. In the transplanted group, the concentrations of IL6, $IL-1{\beta}$, and GDNF were no significant difference between day 1 and 7, although GDNF seemed to be elevated. Serum NSE concentration was significantly elevated after transplantation, but not in CSF. Conclusion : It is suggested that autologous umbilical cord blood transplantation in preterm very low birth weight infant is safe to apply clinical practice. Long term follow up study should be needed to evaluate the potential therapeutic effect of umbilical cord blood transplantation for neuroprotection.

An Analysis on the Current Status of Daily Outdoor Play Parents Recognize (Focused on Gyeonggi-do) (부모가 인식하고 있는 일상적 바깥놀이 실태 분석 (경기도를 중심으로))

  • Kim, Yong-Sook;Yoon, Hee-Bong;Yoo, Ji-Eun
    • The Journal of the Korea Contents Association
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    • v.17 no.12
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    • pp.461-472
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    • 2017
  • The purpose of this study is to analyze the current status and condition of children's playgrounds in K which parents recognize as in Gyeonggi-do and provide basic data for the qualitative environment for daily outdoor play of young Children. To do so, a survey of 269 parents living in Gyeonggi-do was conducted and reconstructed based on the advanced research related to outdoor play. Also it was evaluated and revised after consultation with 3 children education specialists. The repossessed questionaries were frequency-analyzed with SPSS 20.0 program. The result of the analysis on outdoor playgrounds is in the following. First of all, it was analyzed that parents required 1 or 2 hours for their children to play outdoors in a type of "forest playgrounds." Moreover, they said that it was really important for the children to feel "interesting and funny" during the outdoor play, and they recognized that the play would be helpful for the children's socialization. However, they felt that a risk factor of the outdoor play was "a vehicle risk in streets." Secondly, the study suggested that there were outdoor playgrounds around parents' houses, and a type of the outdoor play was "a playground installed in the apartment complex." Furthermore, most of the parents weren't satisfied with the outdoor play because the apartment neglected the management of the playgrounds, and there were no playing facilities that were good enough to derive children's curiosity and adventurous spirit. The result also showed that most of the children played outdoors with "their mothers," and they participated in indoor activities, especially playing a game or watching TV rather than outdoor activities after attending a children educational institute. Lastly, when it comes to areas of outdoor play to be improved, it was necessary to "expand playgrounds that children can use for each season," build "safe playgrounds" for a type of the outdoor play," provide "playing spaces" for a spatial type, and "control vehicles around the playgrounds and deal with dangerous things" to prevent safety accidents. The result can expand the understanding of outdoor play for Young Children and offer discussions about the relevant organizations and studies.

Optimum Design of Soil Nailing Excavation Wall System Using Genetic Algorithm and Neural Network Theory (유전자 알고리즘 및 인공신경망 이론을 이용한 쏘일네일링 굴착벽체 시스템의 최적설계)

  • 김홍택;황정순;박성원;유한규
    • Journal of the Korean Geotechnical Society
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    • v.15 no.4
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    • pp.113-132
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    • 1999
  • Recently in Korea, application of the soil nailing is gradually extended to the sites of excavations and slopes having various ground conditions and field characteristics. Design of the soil nailing is generally carried out in two steps, The First step is to examine the minimum safety factor against a sliding of the reinforced nailed-soil mass based on the limit equilibrium approach, and the second step is to check the maximum displacement expected to occur at facing using the numerical analysis technique. However, design parameters related to the soil nailing system are so various that a reliable design method considering interrelationships between these design parameters is continuously necessary. Additionally, taking into account the anisotropic characteristics of in-situ grounds, disturbances in collecting the soil samples and errors in measurements, a systematic analysis of the field measurement data as well as a rational technique of the optimum design is required to improve with respect to economical efficiency. As a part of these purposes, in the present study, a procedure for the optimum design of a soil nailing excavation wall system is proposed. Focusing on a minimization of the expenses in construction, the optimum design procedure is formulated based on the genetic algorithm. Neural network theory is further adopted in predicting the maximum horizontal displacement at a shotcrete facing. Using the proposed procedure, various effects of relevant design parameters are also analyzed. Finally, an optimized design section is compared with the existing design section at the excavation site being constructed, in order to verify a validity of the proposed procedure.

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Multilateral Approach to forming Air Logistics Hub on North East Asia Region (동북아 항공물류허브을 구축하기 위한 다자적 접근방안)

  • Hong, Seock-Jin
    • The Korean Journal of Air & Space Law and Policy
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    • v.19 no.2
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    • pp.97-136
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    • 2004
  • The Northeast Asian air cargo market has expanded tremendously as a result of the opening up of the Chinese market. The importance of the Asia-Pacific region in the global air transport has also increased. The exchange of human and material resources, services, and information in Northeast Asia, which is expected to increase in the near future, requires that the airlines operating within this region adopt a more liberalized approach. This paper introduced alternatives which can be applied to the Northeast Asian airlines industry so as to bring about the integration of regional air transport: First, this paper found a need for individual Northeast Asian nations to alter their policies towards the airlines industry. Second, each country should further liberalize their respective domestic air transport. Third, there is a need for freer air service agreements to be signed between the nations of Northeast Asia. Fourth, the strategic alliances between the airlines operating in Northeast Asia should be further strengthened. Fifth, this liberalization process should be carried out in an incremental manner, beginning with more competitive airports and routes, or with less-in-demand routes. Sixth, there is a need for a shuttle system to be put into place between the main airports in China, Korea, and Japan. Seventh, these three nations jointly develop aviation safety and security systems that are in accordance with international standards. Eighth, the liberalization process of the aviation industry should be undertaken in conjunction with other related fields. Ninth, organizations linking together civil aviation organization in the Asia-Pacific area should be formed, as should each government linking together. By doing so, these countries will be able to establish regular venues through which to exchange opinions on the integration and liberalization of the air cargo market so as to induce the gradual liberalization of the actual market. The liberalization of the air transport in Northeast Asia will prove to be a daunting task in the short term. However, if the Chinese airlines continue to exhibit continuous growth and Japanese airlines are able to complete their move towards a low-cost structure, this process could be completed earlier than expected. Over the last twenty five years the air transport has undergone tremendous changes. The most important factor behind these changes has been the increased liberalization of the market. As a result, rates have decreased while demand has increased. This has resulted in turning the air transport industry, which was long perceived as an industry in decline, into a high-growth industry. The only method of increasing regional exchanges in the air transport is to pursue further liberalization. The country which implements this liberalization process at the earliest date may very well emerge as a leading force within the air transport industry.

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Comparison of Domestic and Foreign Design Standards for Overall Stability of Soil Nailed Slopes (쏘일네일 보강 비탈면의 전체 안정성에 대한 국내외 설계기준 비교)

  • Kim, Tae-Won;You, Kwang-Ho
    • Journal of the Korean GEO-environmental Society
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    • v.20 no.6
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    • pp.5-13
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    • 2019
  • The international trend in soil nailed wall design has been evolved from the allowable stress design to limit state design and it is still currently ongoing. The design guidelines in Korea and Hong Kong still adopts the allowable stress design philosophy while those in others mostly do the limit state design. In this study, four soil nail design methods presented in the major design guidelines (U.S. FHWA GEC 7 (2015), Clouterre in France (1991), Soil nailing - best practice guidance in U.K. (CIRIA, 2005), Geoguide 7 in Hong Kong (2008) and Design standard for slope reinforcement work in Korea (KDS 11 70 15 f: 2016)) are described and analyzed in brief. The factor of safety and CDR (Capacity-to-Demand Ratio) which is used to measure the degree of conservatism of a design guide are obtained for the two cases. One is the design example presented in CIRIA (2005) and the other is in-situ loading test performed on the top of backfill of the soil nail wall to investigate the conservatism of design guidelines. It is revealed that the design method in overall stability of soil nail walls in domestic design method (CDR=0.78) is the most conservative and those by Clouterre (CDR=0.99, 1.09), Geoguide 7 (CDR=1.13, 0.97), U.S. FHWA (CDR=1.09, 1.07) and CIRIA (CDR=1.40, 1.16) in order from the second most conservative to the least conservative for the design example presented in CIRIA. For the in-situ loading test performed on the top of backfill of the soil nail wall, the order of conservatism is identical except that the places of Geoguide 7 (CDR=0.66, 0.72) and FHWA (CDR=0.73, 0.72) are changed. However, the results obtained among U.S. FHWA (2015) and Clouterre (1991) and Geoguide 7 (2008) are not so different.

A Study on Industry-specific Sustainability Strategy: Analyzing ESG Reports and News Articles (산업별 지속가능경영 전략 고찰: ESG 보고서와 뉴스 기사를 중심으로)

  • WonHee Kim;YoungOk Kwon
    • Journal of Intelligence and Information Systems
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    • v.29 no.3
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    • pp.287-316
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    • 2023
  • As global energy crisis and the COVID-19 pandemic have emerged as social issues, there is a growing demand for companies to move away from profit-centric business models and embrace sustainable management that balances environmental, social, and governance (ESG) factors. ESG activities of companies vary across industries, and industry-specific weights are applied in ESG evaluations. Therefore, it is important to develop strategic management approaches that reflect the characteristics of each industry and the importance of each ESG factor. Additionally, with the stance of strengthened focus on ESG disclosures, specific guidelines are needed to identify and report on sustainable management activities of domestic companies. To understand corporate sustainability strategies, analyzing ESG reports and news articles by industry can help identify strategic characteristics in specific industries. However, each company has its own unique strategies and report structures, making it difficult to grasp detailed trends or action items. In our study, we analyzed ESG reports (2019-2021) and news articles (2019-2022) of six companies in the 'Finance,' 'Manufacturing,' and 'IT' sectors to examine the sustainability strategies of leading domestic ESG companies. Text mining techniques such as keyword frequency analysis and topic modeling were applied to identify industry-specific, ESG element-specific management strategies and issues. The analysis revealed that in the 'Finance' sector, customer-centric management strategies and efforts to promote an inclusive culture within and outside the company were prominent. Strategies addressing climate change, such as carbon neutrality and expanding green finance, were also emphasized. In the 'Manufacturing' sector, the focus was on creating sustainable communities through occupational health and safety issues, sustainable supply chain management, low-carbon technology development, and eco-friendly investments to achieve carbon neutrality. In the 'IT' sector, there was a tendency to focus on technological innovation and digital responsibility to enhance social value through technology. Furthermore, the key issues identified in the ESG factors were as follows: under the 'Environmental' element, issues such as greenhouse gas and carbon emission management, industry-specific eco-friendly activities, and green partnerships were identified. Under the 'Social' element, key issues included social contribution activities through stakeholder engagement, supporting the growth and coexistence of members and partner companies, and enhancing customer value through stable service provision. Under the 'Governance' element, key issues were identified as strengthening board independence through the appointment of outside directors, risk management and communication for sustainable growth, and establishing transparent governance structures. The exploration of the relationship between ESG disclosures in reports and ESG issues in news articles revealed that the sustainability strategies disclosed in reports were aligned with the issues related to ESG disclosed in news articles. However, there was a tendency to strengthen ESG activities for prevention and improvement after negative media coverage that could have a negative impact on corporate image. Additionally, environmental issues were mentioned more frequently in news articles compared to ESG reports, with environmental-related keywords being emphasized in the 'Finance' sector in the reports. Thus, ESG reports and news articles shared some similarities in content due to the sharing of information sources. However, the impact of media coverage influenced the emphasis on specific sustainability strategies, and the extent of mentioning environmental issues varied across documents. Based on our study, the following contributions were derived. From a practical perspective, companies need to consider their characteristics and establish sustainability strategies that align with their capabilities and situations. From an academic perspective, unlike previous studies on ESG strategies, we present a subdivided methodology through analysis considering the industry-specific characteristics of companies.

A Study on the Optimization Methods of Security Risk Analysis and Management (경비위험 분석 및 관리의 최적화 방안에 관한 연구)

  • Lee, Doo-Suck
    • Korean Security Journal
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    • no.10
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    • pp.189-213
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    • 2005
  • Risk management should be controlled systematically by effectively evaluating and suggesting countermeasures against the various risks which are followed by the change of the society and environment. These days, enterprise risk management became a new trend in the field. The first step in risk analysis is to recognize the risk factors, that is to verify the vulnerabilities of loss in the security facilities. The second step is to consider the probability of loss in assessing the risk factors. And the third step is to evaluate the criticality of loss. The security manager will determine the assessment grades and then the risk levels of each risk factor, on the basis of the result of risk analysis which includes the assessment of vulnerability, the provability of loss and the criticality. It is of great importance to put the result of risk analysis in mathematical statement for a scientific approach to risk management. Using the risk levels gained from the risk analysis, the security manager can develop a comprehensive and supplementary security plan. In planning the risk management measures to prepare against and minimize the loss, insurance is one of the best loss-prevention programs. However, insurance in and of itself is no longer able to meet the security challenges faced by major corporations. The security manager have to consider the cost-effectiveness, to suggest the productive risk management alternatives by using the security files which contains every information about the security matters. Also he/she have to reinforce the company regulations on security and safety, and to execute education repeatedly on security and risk management. Risk management makes the most efficient before-the-loss arrangement for and after-the-loss continuation of a business. So it is very much important to suggest a best cost-effective and realistic alternatives for optimizing risk management above all, and this function should by maintained and developed continuously and repeatedly.

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