• Asian Journal of Atmospheric Environment
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• v.10 no.3
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• pp.125-136
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• 2016

In this study, the effects of the mesh barrier on the free dispersion of ammonia were numerically investigated under different atmospheric conditions. This study presents the detail and flow feature of the dispersion of ammonia through the mesh barrier on various free stream conditions to decline and limit the toxic danger of the ammonia. It is assumed that the dispersion of the ammonia occurred through the leakage in the pipeline. Parametric studies were conducted on the performance of the mesh barrier by using the Reynolds-averaged Navier-Stokes equations with realizable k-${\varepsilon}$ turbulence model. Numerical simulations of ammonia dispersion in the presence of mesh barrier revealed significant results in a fully turbulent free stream condition. The results clearly show that the flow behavior was found to be a direct result of mesh size and ammonia dispersion is highly influenced by these changes in flow patterns in downstream. In fact, the flow regime becomes laminar as flow passes through mesh barrier. According to the results, the mesh barrier decreased the maximum concentration of the ammonia gas and limited the risk zone (more than 500 ppm) lower than 2 m height. Furthermore, a significant reduction occurs in the slope of the upper boundary of $NH_3$ risk zone distribution at downstream when a mesh barrier is presented. Thus, this device highly restricts the leak distribution of ammonia in the industrial plan.

• The Journal of Engineering Geology
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• v.16 no.4 s.50
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• pp.351-357
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• 2006

Recently there is increasing the flow of hazardous chemical substances caused by industrial waste waters into a main river. It is needed to make the high treatment in drinking water treatment plants for reducing a health risk. Therefore, the monitoring of trace hazardous chemical substances by the industrial waste water inflow is available increasing economical efficiency of river management as well as reduction of risk. In this study, the most important substance among numerical and quantitative trace hazardous chemicals is Hexachlorobutadiene in an effluent of industrial wastes. However all items of GroupII which was included with semiconductor, electricity/electron and metal assemble was not detected. It means that we must consider the characteristics and behavior of load pollutants to water resources to select monitoring items. That was called 'preparatory monitoring'. We can reduce an economical consumption as well as risks from these pollutants using the preparatory monitoring.

• Korean Journal of Health Education and Promotion
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• v.35 no.5
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• pp.17-24
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• 2018

Objectives: After many national physical activity guidelines have established, recent changes are deep and rapid. So the major features and implication to reverse worsening Korean physical activity indicator is desprate but related knowledge and informations are few. So review of recent features and implications of new physical activity guidelines have made. Methods: National physical activity guidelines of advanced countries were searched through snowballing methods. Major features were described according to the nation. Implication were drew through discussion for Korean realitiy. Results: New Australian physical activity and sedentary behaviour guideline explicitly included sedentary behaviour. The age in the guideline expanded to early years. Canada also presented 24-hour movement guidelines to early years. The second generation of the physical activity guidelines reflects the extensive amount of new knowledge. New aspects include discussions of additional health benefits related to brain health, additional cancer sites, and fall-related injuries; immediate and longer term benefits for how people feel, function, and sleep; further benefits among older adults and people with additional chronic conditions; risks of sedentary behavior and their relationship with physical activity; elimination of the requirement for physical activity benefits to occur in bouts of at least 10 minutes; and tested strategies that can be used to get the population more active. Conclusions: The most important message from the new guidelines is that the greatest health benefits accrue by moving from no, to even small amounts of, physical activity. Multiple studies demonstrate that the steepest reduction in disease risk occurs at the lowest levels of physical activity. People need to understand that even small amounts of physical activity are beneficial and that reductions in the risk of disease and disability occur by simply getting moving. So various evidence based proven strstegies are needed in Korea including workforce training.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.5263-5272
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• 2012

Background: Gastric cancer (GC) is one of the most common cancers in China. Adjuvant chemotherapy (AC) is a routine auxiliary treatment for GC recommended by the guidelines issued in 2011 by the Ministry of Health of the People's Republic of China, but the relevant credible consequences in China have been insufficient because of China's late start and ethical concerns. Methods: A series of databases, including Cochrane Library, MEDLINE, EMBASE, the Chinese database of the National Knowledge Infrastructure and the VIP database, were searched by 2 reviewers independently for studies investigating AC for GC through March 2012. The retrieved literature was screened according to the eligibility criteria. Results: A total of 35 randomized control trials (RCTs) were subjected to the final analysis, including 4,043 patients in treatment group and 3,884 in the control group, as well as 4 clinical-control trials (CCTs), which accessed the final analysis with 238 and 252 patients, respectively. AC reduced the risk of death as a protective treatment with statistical significance (HR=0.91, 95%CI: [0.85, 0.97], P=0.002), and it seemed more effective for Asian than non-Asian patients. The effects of AC were not influenced by the starting time (P>0.05). D2 lymphadenectomy-based chemotherapy was effective (HR=0.89, 95%CI: [0.80, 0.99], P=0.04). Oral S-1 40 mg/m2 after D2 lymphadenectomy might be a better choice for Asians with advanced GC and might result in a greater reduction of adverse events than in non-Asian patients. GRADE quality assessment determined that the strength of the evidence from foreign studies from Europe, the United States and Asian countries other than China was high, while it was moderate for Chinese studies. Conclusion: AC was effective or even curative in Chinese patients in general, although it is still necessary to optimize a targeted AC scheme for Chinese patients with GC.

• Journal of the Korean Dietetic Association
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• v.11 no.1
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• pp.125-132
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• 2005

Hypercholesterolemia has been regarded as a major risk factor of coronary heart disease(CHD). CHD is increasing in recent years among Koreans due to westernization of lifestyle and dietary behaviors. In the United States, implementation of the National Cholesterol Education Program(NCEP) had resulted 40% decline in mortality from CHD. This study was designed to evaluate the effect of medical nutrition therapy on serum lipid levels and discuss the effective nutrition education contents. Thirty outpatients(Male 40%, female 60%) with hypercholesterolemia were educated by medical nutrition therapy(MNT) protocol. At first visit and after three months of MNT, we assessed serum lipid profile, body weight and surveyed general characteristics, lifestyle and food habits through questionnaire. After 12 weeks of MNT, there were significant reductions in serum cholesterol and low-density lipoprotein cholesterol(LDL-C). Foods habits and lifestyle were changed to the desirable patterns. These results indicate that lipid profile is improved by changes of dietary behaviors and lifestyle. Especially in case of obesity, cholesterol lowering effect of MNT was more powerful. Consequently, MNT is effective on reduction of serum lipids by behavior change in hypercholesterolemic patients.

• Research in Community and Public Health Nursing
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• v.16 no.2
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• pp.167-176
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• 2005

Purpose: The purpose of this study was to identify factors to predict of condom use for the prevention of sexually transmitted diseases (STDs) among sex workers in a Korean community. The theoretical ground of this study was the Interaction Model of Client Health Behavior. Method: A descriptive, cross sectional and retrospective research design was employed in this study. A total of 100 sex workers who take a clinical check-up on STDs regularly at W Public Health Center were recruited by convenient sampling, and with consent to participate in this study. All of the measures were piloted, and the reliability of each scale ranged from 0.7 to 0.9. Data were analyzed using discriminating function analysis with SPSS-PC. Results: Five independent measures (partner preference for using condoms, subjects desire to prevent STD, age, type of relationship and sexual self-determination) contributed significantly to the best discriminating function. The discriminating function analysis resulted in correct classification of 83.1% of the respondents into their corresponding groups. Conclusion: Condoms are a main means of STDs prevention. Risk-reduction interventions that enhance communication skills and intrinsic motivation will be effective in increasing condom use to prevent STDs among sex workers.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.263-266
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• 1997

Three dimensional numerical model based on the finite element method(FEM) were developed to predict the mechanical behavior of hip implants. The purpose of this study is to investigate the stress distribution of two types of cementless total hip replacement femoral component -a straight stem and a curved stem, and to compare their effect on the stress shielding between two types by three dimensional finite element method. The authors analyzed von Mises stress in the cortex & stem and compared the stress between the straight and the curved stem. In comparison of stresses between two different design of femoral stem, there was 25% more decrease of stress in straight stem than curved stem in the medial cortex at proximal region. The straight stem had consistently much lower stresses than the curved stem throughout the whole medial cortex with maximum 70% reduction of stress. However, there was little change in stress between nature and 2 implanted femur throughout the lateral cortex. Stress of femoral stem was much higher in the straight stem than the curved stem up to 60%. The straight stem had more chance of stress shielding and a risk of fatigue fracture of the stem compared with the curved stem in noncement hip arthroplasty. In design of femoral stem still we have to consider to develop design to distribute more even stress on the proximal medial cortex.

• Journal of Internet Computing and Services
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• v.18 no.5
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• pp.103-112
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• 2017

Work engagement and job burnout are crucial problems in Korea, particularly in the business environment, and they also indicate people's motivation. Online-based teams in e-business also have these issues. Especially the role of the leader in this new type of teams is more crucial for members' motivation, behavior, and performance. Contingency leadership theories posit that different situations need different traits or behaviors of a leader. For an online-based team, which is internet-based team in e-business, a leader should use specific communication strategies to enhance a team's performance and members' motivation. In an online-based team and an offline-based team, the ways in which leaders motivate members will be different. This paper suggests particular communicative strategies for leaders of online situations. Online-based team members communicate using mobile phones or IT tools, and leaders mayinfluences members in virtual meetings. Moreover, online-based leadership needs to be more entrepreneurial and risk encouraging, and less conservative than offline-based leadership. In addition, online-based leadership should be energetic, decisive, adaptable, and inspiring, and furtherutilize communication tools such as being more gregarious/talkative, assertiveness, linguistic diversity and affect. This paper explains the roles of communicative elements such as coordination, expression, direction-giving/uncertainty reduction, empathy, meaning-making, satisfaction, and competence to decrease job burnout and to increase work engagement. The purpose of this study is to suggest communication strategies' differentiated influences on work engagement and job burnout in an online-based team.

• Food Science and Biotechnology
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• v.27 no.6
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• pp.1865-1869
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• 2018

This study examined the effects of alfalfa seed germination on growth of Salmonella enterica. We investigated the population changes of S. enterica during early sprout development. We found that the population density of S. enterica, which was inoculated on alfalfa seeds was increased during sprout development under all experimental temperatures, whereas a significant reduction was observed when S. enterica was inoculated on fully germinated sprouts. To establish a model for predicting S. enterica growth during alfalfa sprout development, the kinetic growth data under isothermal conditions were collected and evaluated based on Baranyi model as a primary model for growth data. To elucidate the influence of temperature on S. enterica growth rates, three secondary models were compared and found that the Arrhenius-type model was more suitable than others. We believe that our model can be utilized to predict S. enterica behavior in alfalfa sprout and to conduct microbial risk assessments.

• International Journal of Highway Engineering
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• v.18 no.5
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• pp.39-47
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• 2016

PURPOSES : Road subsidence occurs owing to road cavities, which cause many social and environmental problems, especially in cities. Recently, road cavities were detected by various ground radars and repair works were carried out against the detected cavities. The condition assessments related to the road cavities are necessary to understand the potential risk of the cavities. Therefore, in this study, a numerical study was performed to assess the various conditions of road cavities. METHODS : The numerical method adopted in this study is the discrete element approach, and it is suitable for analyzing the condition because it can consider the movement of the soil particles in the surrounded cavity areas. In addition, the triaxial test was modeled and performed under various cavity conditions inside the specimens. RESULTS : The conditions of different cavity locations and shapes were analyzed to identify the effect of cavity state. Three general cases of particle size distributions were formulated to identify the effect of surrounding ground conditions. As a result, the degree of decrement and volumetric strain were varied depending on the locations and shapes of the cavity. Only minor changes were observed when the particle size distributions were altered. CONCLUSIONS : The strength reduction was higher when the cavity formed was larger and located in the upper zone. Similar to the cavity shape, strength reduction and volume deformation are more influenced by the width than the length of the cavities. There is an influence from ground conditions such as the particle size distribution, especially on the wide cavity.