• Title/Summary/Keyword: research activities

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POSCA: A computer code for fission product plateout and circulating coolant activities within the primary circuit of a high temperature gas-cooled reactor

  • Tak, Nam-il;Lee, Jeong-Hun;Lee, Sung Nam;Jo, Chang Keun
    • Nuclear Engineering and Technology
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    • v.52 no.9
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    • pp.1974-1982
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    • 2020
  • Numerical prediction of fission product plateout and circulating coolant activities under normal operating conditions is crucial in the design of a high temperature gas-cooled reactor (HTGR). The results are used for the maintenance and repair of the components as well as the safety analysis regarding early source terms under loss of coolant accident scenarios. In this work, a new computer code named POSCA (Plate-Out Surface and Circulating Activities) was developed based on a one-dimensional model to evaluate fission product plateout and circulating coolant activities within the primary circuit of a HTGR. The verification and validation of study for the POSCA code was done using available analytical results and two in-pile experiments (i.e., OGL-1 and VAMPYR-1). The results of the POSCA calculations show that POSCA is able to simulate plateout and circulating coolant activities in a HTGR with fast computation and reasonable accuracy.

Angiotensin Ⅰ Converting Enzyme(ACE) Inhibitory Activities of Laver(Porphyra tenera) Protein Hydrolysates (김 단백질 가수분해물의 Angiotensin Ⅰ 전환효소 저해 활성)

  • Kim Young-Myoung;Do Jeong-Ryong;In Jae-Pyung;Park Jong-Hyuk
    • The Korean Journal of Food And Nutrition
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    • v.18 no.1
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    • pp.11-18
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    • 2005
  • Angiotensin Ⅰ converting enzyme(ACE) inhibitory activities of laver(Porphyra tenera) protein hydrolysates were investigated by enzymes used for hydrolysis, molecular fractions and drying methods. For the enzymatic hydrolysis, crude laver protein, separated by filtration of water extract of dried laver extracted with 20 times(w/v) water for 3 hours at boiling temperature, were hydrolyzed with three commercial protease, Pepsin, alcalase and maxazyme NNP at optimal conditions. The yield of hydrolysis and ACE inhibitory activities of which were high in order of pepsin, alcalase and maxazyme NNP. ACE inhibitory activities of laver hydrolysates by molecular levels were high in order of 3 kDa > 10 kDa > 3∼10 kDa, and the IC/sub 50/ ACE inhibitory activities by molecular lebels were 4 mg/mL(3 kDa), 5 mg/mL(total hydrolysate), and 20 mg/mL(10 kDa), respectively. The storage stability of dried laver hydrolysates at 20℃ were strongly affected by drying methods, hot air dried of which were much stabler than freeze-dried one.

Antioxidative Activities of Phenolic Compounds Isolated from Inonotus obliquus (차가버섯으로부터 분리한 페놀성 화합물의 항산화효과)

  • Kim, Hyoung-Ja;Jin, Chang-Bae;Lee, Yong-Sup
    • Korean Journal of Pharmacognosy
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    • v.38 no.2 s.149
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    • pp.164-169
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    • 2007
  • ln our continued search for biologically active compounds from traditional medicine, we found that ethyl acetate fraction from Inonotus obliquus showed potent antioxidant activities on three different cell-free bioassay systems. Bioassay-directed chromatographic fractionation of the ethyl acetate fraction from Inonotus obliquus afforded four phenolic compounds, 4-(3,4-dihydroxyphenyl)-(E)-3-buten-2-one (1) , 3,4-dihydroxybenzaldehyde (2), protocatechuic acid (3) and caffeic acid (4) along with three sterols such as lanosterol (5), ergosterol peroxide (6) and 9,11-dehydroergosterol peroxide (7). Among isolates, phenolic compounds (1-4) were assessed for antioxidant activities. Almost phenolic compounds showed potent DPPH and superoxide anion radicals scavenging and lipid peroxidation inhibitory activities indicating that these phenolic compounds contribute to the antioxidative activities of I. obliquus. Compounds 2-3 and 7 were isolated for the first time from this plant.

Empirical Analysis of the Influence of Tourism Industry Knowledge Management Activities on Knowledge Management Efficiency (관광산업에서의 지식경영활동과 지식경영효율성 향상에 관한 실증연구)

  • Kwon, Soon-Jae;Lee, Kun-Chang
    • Knowledge Management Research
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    • v.10 no.3
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    • pp.1-16
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    • 2009
  • Recent trends in business are characterized by recognition of the importance of knowledge assets. Especially, this phenomenon is receiving more momentum as our society goes digital rapidly. The concept of Knowledge Management has long been used as an effective way of restructuring the management process of a firm. In literature regarding knowledge management, a number of successful cases were reported, where knowledge-based management activities could dramatically enhance a firm's strategic performance for years. However, there exists very little research investigating the effect of knowledge management on corporate competitiveness. Researchers as well as practitioners need more rigorous results about such issues, especially how much the knowledge management strategic initiatives may have an influence on the firm's competitiveness. In this sense, we need an empirical study adopting statistical approaches due to the existence of abundant knowledge management case studies. To fill this research void, this study proposes a research model testing whether knowledge management activities could improve corporate competitiveness. We collected 321 valid questionnaires from participants in knowledge management activities in the tourism industry and applied a structural equation model. Empirical results showed that knowledge management activities have a positive impact on knowledge management efficiency and finally corporate competitiveness. We hope that this study will shed light on further rigorous studies considering tourism industry as a major strategic activity.

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NON-VALUE ADDING ACTIVITIES IN SOUTH AFRICAN CONSTRUCTION: A RESEARCH AGENDA

  • Fidelis Emuze;John Smallwood
    • International conference on construction engineering and project management
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    • 2011.02a
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    • pp.453-458
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    • 2011
  • The construction industry's importance to nation building, economic empowerment, and contributions to global commerce cannot be over emphasised. However, poor productivity, accidents, rework, time and cost overruns, and client dissatisfaction have characterised the industry performance in a multi-dimensional way. The central issue in this particular research is the seemingly inadequate achievement of optimum performance in the construction process, either with respect to value for money for the client and the entire construction supply chain or value in terms of the utility derived from built assets in spite of efforts by government and governmental bodies such as the Construction Industry Development Board (cidb) to increase industry performance. Therefore, based upon an extensive review of related literature, the paper reports on effects and causes of non-value adding activities in the construction industry in general, and South African construction in particular. The research findings indicate that activities that can be referred to as non-value activities are not only prevalent, but they can also be held responsible for performance related issues in terms of cost, time, quality and health and safety (H&S) in construction; and the exploration of pluralism in the research methodology may result in a robust model based upon the system dynamics approach. Therefore, the study suggests that there is major scope for value optimisation in the construction process especially in terms of availability and implementation of interventions, which have not only proven successful in other industries, but are also adaptable in the construction industry context.

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The New Role of Maritime Institutions from the Viewpoints on the Maritime Education, Training and Research Activities

  • Comert, Ali;Nomura, Ryuta;Furusho, Masao
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2004.08a
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    • pp.113-120
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    • 2004
  • Considering the present and expected demand for human resources by the maritime community, its quantity and quality depend on the number of the ships and the technology applied to them. Scientific and economic developments in this community bring the intensive use of modem technology for many of ships operation. Generally it effects to reduce the quantity of manpower, while it increases the requirement of qualifications of human resources to utilize such advanced technology. Considering above, the maritime education, training and research activities should be revised and updated according to the demand of the community. Because of a difference between the transition of the demand for the human resources and development of the maritime education, training and research activities, there are two most common questions as “What to teach” and “How to teach”. The first question has been asked for many years. The contents of maritime education and training are always related to the existing maritime knowledge and technology and should be updated with consideration of changes of the demand namely “Globalisation of maritime community”. It brings globalisation of the maritime education, training and research activities. The second question is still keeping us busy to look for the best way. Presently traditional methods are used together with new system, while the use of sophisticated simulation, communication and information systems etc. and it is changing our understanding on teaching. This paper introduces the new role of Maritime Institutions from the viewpoints of the maritime education. training and research activities. The role of guide for seafarers and maritime companies is always essential and the concepts such as “Refreshment Training”, “On the Job Training”, “Lifelong” or “Continuous Training” bring new understanding to the training period, trainee's age and position. As a result, the maritime institutions should be ready for their new role, which is, in brief, guiding the maritime society, recommending and providing new learning environments, organising research and developments, performing the education, training and assessment, improving existing methods and developing new methods of the education, training and assessment.

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Occupational Injury Prevention Research in NIOSH

  • Hsiao, Hongwei;Stout, Nancy
    • Safety and Health at Work
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    • v.1 no.2
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    • pp.107-111
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    • 2010
  • This paper provided a brief summary of the current strategic goals, activities, and impacts of the NIOSH (National Institute for Occupational Safety and Health) occupational injury research program. Three primary drivers (injury database, stakeholder input, and staff capacity) were used to define NIOSH research focuses to maximize relevance and impact of the NIOSH injury-prevention-research program. Injury data, strategic goals, program activities, and research impacts were presented with a focus on prevention of four leading causes of workplace injury and death in the US: motor vehicle incidents, falls, workplace violence, and machine and industrial vehicle incidents. This paper showcased selected priority goals, activities, and impacts of the NIOSH injury prevention program. The NIOSH contribution to the overall decrease in fatalities and injuries is reinforced by decreases in specific goal areas. There were also many intermediate outcomes that are on a direct path to preventing injuries, such as new safety regulations and standards, safer technology and products, and improved worker safety training. The outcomes serve as an excellent foundation to stimulate further research and worldwide partnership to address global workplace injury problems.

Vertical distirbution of $^{137}Cs\;and\;^{90}Sr$ activities in the soils of Korea (토양 중 $^{137}Cs$$^{90}Sr$의 깊이별 분포특성)

  • Cha, H.J.;Park, D.;Park, H.;Kang, M.J.;Lee, W.;Choi, G.S.;Cho, Y.H.;Chung, K.H.;Lee, H.P.;Shin, H.S.;Lee, C.W.
    • Journal of Radiation Protection and Research
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    • v.29 no.3
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    • pp.197-204
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    • 2004
  • Vertical distributions of $^{137}Cs\;and\;^{90}Sr$ activities are studied for the soils of six areas, Korea (Gori, Yeonggwang, Uljin, Weolseong, Goseong and Jeju). The soils from 6 areas are at geographically different locations with the different environmental conditions and parent rook. The activities of $^{137}Cs\;and\;^{90}Sr$ vary N.D.(below detection limit) to 185 Bq/kg and 2.79 - 8.06 Bq/kg, respectively. Activities of $^{137}Cs\;and\;^{90}Sr$ show the highest value at the surface soil and decrease with depth. $^{137}Cs$ activities at the top surface soils are positively correlated with annual precipitation and organic carbon content with little relationship with mean grain size and the clay content. The highest $^{137}Cs$activities are found at the Jeju site, followed by the Goseong site of which soils have much different parent rock and textural properties. Though the activities of $^{137}Cs\;and\;^{90}Sr$ on the basis of dry weight are higher in Jeju soils than in Goseong soils, their inventories are similar in both soils due to their textural differences.

Safety and Health Perceptions in Work-related Transport Activities in Ghanaian Industries

  • Atombo, Charles;Wu, Chaozhong;Tettehfio, Emmanuel O.;Nyamuame, Godwin Y.;Agbo, Aaron A.
    • Safety and Health at Work
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    • v.8 no.2
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    • pp.175-182
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    • 2017
  • Background: With the recent rapid industrialization, occupational safety and health (OSH) has become an important issue in all industrial and human activities. However, incidents of injuries and fatality rates in the Ghanaian industry sector continue to increase. Despite this increase, there is no evidence regarding the element of OSH management in transport activities in Ghanaian industries. Thus, this study aims to examine the perceptions regarding the importance of safety and health in work-related transport activities in Ghanaian industries. Methods: A survey data collection technique was used to gather information on best safety practices over a 5-month period. We randomly selected 298 respondents from industries to answer structured questionnaires. The respondents included drivers, transport managers, and safety engineers. Standard multiple regression model and Pearson product-movement correlation were used to performed the analysis. Results: The result shows that for interventions to improve safety and health, concentration has been on drivers' safety practice with less attention to safe driving environments and vehicle usage. Additionally, the respondents are aware of the importance of OSH in transport activities, but the level of integration does not measure up to the standard to reduce operational accidents and injuries. Finally, strong commitment to changing unsafe practices at all levels of operations appears to be the effective way to improve safety situations. Conclusion: OSH culture is not fully complied in industries transport activities. This study, therefore, supports the use of safety seminars and training sessions for industry workers responsible for transport operations for better integration of safety standards.

Physiological Activities of Leek Extracts from Allium tuberosum and Allium senescens (호부추와 실부추 추출물의 생리활성 효과)

  • Lim, Tae-Soo;Oh, Hyun-In;Do, Jeong-Ryong;Kim, Hyun-Ku
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.3
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    • pp.301-306
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    • 2006
  • Physiological activities of Allium tuberosum and Allium senescens were examined. Nitrite-scavenging activity, superoxide dismutase (SOD)-like activity and electron-donating ability (EDA) of leeks extracted with water, 50%, and 100% ethanol were measured. Nitrite-scavenging activities at pH 1.2 were most effective in water and 50% ethanol extracts from both samples. SOD-like activities of water and 50% ethanol extracts of both samples were $18.21{\sim}36.33%$ lower than those of 1 and 0.1% L-ascorbate solutions. SOD-like activities of A. tuberosum extracts were higher than those of A. senescens extracts, and water extracts of samples were the highest. EDAs of A. tuberosum extracts were higher ($30.59{\sim}49.68%$) than those of A. senescens extracts, while those of both extracts were lower than 1 and 0.1% L-ascorbate solutions. The results will be useful for understanding the physiological activities of leek extracts.