• Title/Summary/Keyword: Influence area

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The Changes of Specific Surface Area of Soils after Peroxidation and Its Implication for the Calculation of Critical toads of Soil Acidification (Peroxidation 전후의 토양 비표면적 변화와 토양산성화 임계부하량 계산에의 의의)

  • Yeo, Sang-Jin;Lee, Bumhan;Soyoung Sung;Kim, Soo-Jin
    • Journal of the Mineralogical Society of Korea
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    • v.15 no.3
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    • pp.195-204
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    • 2002
  • Mineralogy and the exposed surface area are two of the most important factors controlling dissolution and weathering rates of soils. The mixture of inorganic and organic materials of various size distributions and structures that constitute soils makes the calculation of weathering rates difficult. The surface area of soil minerals plays an important role in most of programs for calculating the weathering rates and critical loads. The Brunauer-Emmett-Teller (BET) measurement is recommended for the measurement of specific surface area. However, BET values measured without organic matter removal are in fact those far all the N2-adsorbed surface areas, including the surfaces covered and aggregated with organisms. Surfaces occupied by organisms are assumed to be more reactive to weathering by organic activities. Therefore, the BET surface area difference before and after organic removal depicts the area occupied by organisms. The present study shows that the BET values after organic matter removal using $H_2$O$_2$ are larger than those without removal by 1.68~4.87 $m^2$/g. This implies that BET measurement without organic removal excludes the reactive area occupied by organisms and that the area occupied by organisms in soils is much larger than expected. It is suggested that specific surface area measurement for calculating weathering rates of mineral soils should be made before and after organic matter removal. The results of a column experiment are presented to demonstrate the potential retarding influence that this organic matter may have on mineral dissolution and weathering.

Shallow Landslide Assessment Considering the Influence of Vegetation Cover

  • Viet, Tran The;Lee, Giha;Kim, Minseok
    • Journal of the Korean GEO-environmental Society
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    • v.17 no.4
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    • pp.17-31
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    • 2016
  • Many researchers have evaluated the influence of vegetation cover on slope stability. However, due to the extensive variety of site conditions and vegetation types, different studies have often provided inconsistent results, especially when evaluating in different regions. Therefore, additional studies need to be conducted to identify the positive impacts of vegetation cover for slope stabilization. This study used the Transient Rainfall Infiltration and Grid-based Regional Slope-stability Model (TRIGRS) to predict the occurrence of landslides in a watershed in Jinbu-Myeon, Pyeongchang-gun, Korea. The influence of vegetation cover was assessed by spatially and temporally comparing the predicted landslides corresponding to multiple trials of cohesion values (which include the role of root cohesion) and real observed landslide scars to back-calculate the contribution of vegetation cover to slope stabilization. The lower bound of cohesion was defined based on the fact that there are no unstable cells in the raster stability map at initial conditions, and the modified success rate was used to evaluate the model performance. In the next step, the most reliable value representing the contribution of vegetation cover in the study area was applied for landslide assessment. The analyzed results showed that the role of vegetation cover could be replaced by increasing the soil cohesion by 3.8 kPa. Without considering the influence of vegetation cover, a large area of the studied watershed is unconditionally unstable in the initial condition. However, when tree root cohesion is taken into account, the model produces more realistic results with about 76.7% of observed unstable cells and 78.6% of observed stable cells being well predicted.

Influences of Job Stress of 119 Briefing Room Workers on Depression (119상황실 근무자의 직무스트레스가 우울에 미치는 영향)

  • Park, Dae-Sung;Nam, Kun-Woo
    • The Korean Journal of Emergency Medical Services
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    • v.12 no.2
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    • pp.85-97
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    • 2008
  • Purpose : This study was cross-sectional study to examine the influence of job stress in 119 briefing room workers and aimed to provide the important basic materials for improving working conditions of 119 briefing room workers and further studies. Methods : This study selected 271 workers of 119 briefing room at National Emergency Management Agency and fire stations, metropolitan cities and provinces to examine the influences of job stress of 119 briefing room workers on depression. and as a result of analysis, the following conclusions. Results : 1) The whole average of job stress measure was 3.30. The highest area was interpersonal relationship factor as 3.41, 'job characteristic factor' as 3.36 and communication factor' as 3.01. 2) Total score of whole items of depression was 11.88 and showed slight depression level. 3) There was static correlation between job stress and depression(r=44.7, p= .000). There were statistically significant static correlations between job stress factor and depression(r= .388, p= .000), interpersonal relationship factor and depression(r= .471, p= .000), and communication factor and depression(r= .386, p= .000). 4) There was statistically significant difference in the influence of job stress on depression(B=8.575, p< .001). Influence of job stress on depression was explained as $R^2=.200$. When job stress factors as independent variables were input, interpersonal relationship factor(B=5.062, p< .001) had the greatest influence on depression and there was no statistically significant difference in communication factor(B=2.490, p< .05). Conclusions : It is considered that development of the various programs including program for getting rid of job stress of 119 briefing room workers and counseling program will be needed. particularly, factors such as human relationships and communication in the area of job stress must be the first priority.

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Causal Analysis of Education Function Space Parameters of University Dormitory (대학기숙사 교육기능공간의 매개변수를 통한 인과분석)

  • Park, Hang-Ja;Park, Sung-Jin;No, Young-Ran
    • Journal of the Korean housing association
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    • v.21 no.4
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    • pp.23-31
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    • 2010
  • This study aims to examine the educational function space of university dormitories at local universities with corridor centered structure in Honam area regions based on direct and indirect parameters on the whole satisfaction of users in residential environment factors and personal characteristics. First, according to relations among parameters, educational and cultural activities of four major activities within the dormitory had indirect influences on social activities, eating and sleeping activities had no direct influence on other activities. And social activity had direct influence on the general satisfaction as an important parameter and educational and cultural activities had indirect influence on the whole satisfaction through social activities. Detailed results show that, in the first educational activities directly affecting the lighting and air conditioning facilities (0.22), safety (0.326), Territoriality (0.327), the space density (-0.167), directions (-0.166) and yeohyang having personal characteristics and the safety of the second cultural activities (0.183), Territoriality (0.361), Aesthetics (-0.13) and the personal characteristics Sex (-0.179), the direct effect, third, and erosion has a direct impact on activity The flexibility of the space factor (-0.128) and Territoriality (0.38) and the personal characteristics grade (0.172), respectively. Fourth in social activities directly affecting the pathfinding (-0.104), and parameter, education (0.388) and cultural activities (0.445), and some of the factors affecting the indirect lighting and air conditioning facilities, safety, and Territoriality, the space density, directions, grade, they could influence through educational activities to be analyzed. That is, territoriality in educational function space is the important factor that users react very sensitively in educational, eating and sleeping activities and educational function space must secure area and division considering personal and public use as the space accommodating activity which is lacking in unit residential space. Accordingly, the safety of educational function space in university dormitory is considered as the fundamental safety matter on the fire prevention, hygiene and cleanness for users in the satisfaction of educational and cultural activities.

The Effects of Brand Image of Dental Clinics Perceived by Healthcare Service Users (치과클리닉에 대한 의료 소비자의 브랜드 이미지가 충성도에 미치는 영향 - 수도권의 의료 소비자 중심으로 -)

  • Cho, Soo Yeon;Lee, Seung Chang
    • Korea Journal of Hospital Management
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    • v.24 no.1
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    • pp.36-47
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    • 2019
  • Purposes : The purpose of this study is to analyze empirically the consturct development of brand trust in dental clinic service and its influence on both satisfaction and brand loyalty of clinic users in Seoul area. Methodology : To test the hypotheses, the structured instrument was employed to question to patients and their guardians who had used dental clinics in the metropolitan area. 207 cases were analyzed with structural equation method through SPSS 18.0 and AMOS 22.0, and findings of the test as follows. Findings : Firstly, both functional and associative images had a positive impact on the brand trust. Especially we found the influence of functional images was greater than that of the brands' associative images. Secondly, the satisfaction of dental clinic users had greater positive influence on the clinics with greater trust. Thirdly, the higher the satisfaction of health service consumers, the more positive effect on brand loyalty. This relationship between the satisfaction of dental clinic users and brand loyalty match the findings of previous studies on relations of similar variables. Practical Implications : This study shows that with greater satisfaction, the referral rate and the revisit rate of users would increase. This implies that dental clinics need to take appropriate actions to build brand trust with advertising and/or PR strategies for a good brand image. It would be necessary to research further expected variables that influence users' brand loyalty in the service, such as the dentists' level of expertise, their relationship level with customers, the quality of dental services and et al..

Study on the influence of flow blockage in severe accident scenario of CAP1400 reactor

  • Pengcheng Gao;Bin Zhang ;Jishen Li ;Fan Miao ;Shaowei Tang ;Sheng Cao;Hao Yang ;Jianqiang Shan
    • Nuclear Engineering and Technology
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    • v.55 no.3
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    • pp.999-1008
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    • 2023
  • Deformed fuel rods can cause a partial blockage of the flow area in a subchannel. Such flow blockage will influence the core coolant flow and further the core heat transfer during the reflooding phase and subsequent severe accidents. Nevertheless, most of the system analysis codes simulate the accident process based on the assumed flow blockage ratio, resulting in inconsistencies between simulated results and actual conditions. This paper aims to study the influence of flow blockage in severe accident scenario of the CAP1400 reactor. First, the flow blockage model of ISAA code is improved based on the FRTMB module. Then, the ISAA-FRTMB coupling system is adopted to model and calculate the QUENCH-LOCA-0 experiment. The correctness and validity of the flow blockage model are verified by comparing the peak cladding temperature. Finally, the DVI Line-SBLOCA accident is induced to analyze the influence of flow blockage on subsequent CAP1400 reactor core heat transfer and core degradation. From the results of the DVI Line-SBLOCA accident analysis, it can be concluded that the blockage ratio is in the range of 40%-60%, and the position of severe blockage is the same as that of cladding rupture. The blockage reduces the circulation area of the core coolant, which in turn impacts the heat exchange between the core and the coolant, leading to the early failure and collapse of some core assemblies and accelerating the core degradation process.

A Dynamic-Stochastic Model for Air Pollutant Concentration (大氣汚染濃度에 관한 動的確率모델)

  • 김해경
    • Journal of Korean Society for Atmospheric Environment
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    • v.7 no.3
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    • pp.156-168
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    • 1991
  • The purpose of this paper is to develop a stochastic model for daily sulphur dioxide $(SO_2)$ concentrations prediction in urban area (Seoul). For this, the influence of the meteorological parameters on the $SO_2$ concentrations is investigated by a statistical analysis of the 24-hr averaged $SO_2$ levels of Seoul area during 1989 $\sim$ 1990. The annual fluctuations of the regression trend, periodicity and dependence of the daily concentration are also analyzed. Based on these, a nonlinear regression transfer function model for the prediction of daily $SO_2$ concentrations is derived. A statistical procedure for using the model to predict the concentration level is also proposed.

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Implications and Situations of Organic Farming in EU (EU 국가의 유기농업 실태와 시사점)

  • Kim, Ho
    • Korean Journal of Organic Agriculture
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    • v.16 no.1
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    • pp.43-57
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    • 2008
  • Organic farming including organic livestock farming in EU has been extended since the latter half of the 19th century. Especially, the organic farming area of Italy, Spain, Germany and U.K. is extensive compared to other EU countries. And organic farming area has been extended rapidly in Portugal and Greece. EU will have an influence on many countries' organic farming on the history and world agriculture. If FTA reaches between Korea and EU, livestock products like ham or sausage will be imported a great deal from EU. So Korea has to establish countermeasures to livestock products export strategies of EU.

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Analysis on Current Printing Industry in Russia (러시아 인쇄 산업 현황 분석 연구)

  • 김병현;신광철
    • Journal of the Korean Graphic Arts Communication Society
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    • v.20 no.1
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    • pp.1-15
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    • 2002
  • The objective of this study was carried out to investigate the study of printing presses and material industry for foreign countries market development(The point of Russia market) by examine the status of printing industry in domestic and russian. The results obtained from this study were the development and insurance of technical in printing industry market seemed to have secure a technical area in 21th century owing to have a exercise influence over about itself and material industry area.

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Gas 분산 기-액 반응조에서 기포운동이 열전달에 미치는 영향

  • Son, Byeong-Jin;Lee, Hyeon
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.8 no.1
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    • pp.10-13
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    • 1979
  • The study for bubbling phenomena to influence heat transfer in gas - liquid contactors. The sparged contactor is gaining importance for gas-liquid chemical reactions. In this paper, correlations between Reynolds number and heat transfer coefficient were studied and experimental expressions were also obtained over broth of areas, namely, laminar area and turbulent area respectively.

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