• Title/Summary/Keyword: point of impact

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Research on Design Capacity Evaluation of Low Impact Development according to Design Criteria (저영향개발 시설 설계 기준에 따른 용량 평가 방법 연구)

  • Im, Jiyeol;Gil, Kyungik
    • Journal of Wetlands Research
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    • v.24 no.1
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    • pp.59-67
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    • 2022
  • The interest in LID facilities is increasing worldwide for recovery of natural water cycle system to destroy by urbanization. However, problems are raised when installation of LID because comprehensive analysis about design capacity adequacy of LID facilities was not conducted completely. In this research, removal efficiency and design volume adequacy of LID facilities were analyzed based on rainfall monitoring data in four LID facilities(Vegetated Swale, Vegetative Filter Strip, Bio-Retention and Permeable Pavement). As a result, group of LID facility designed on WQV was shown higher flow(37%) and pollutants(TSS, BOD, TN and TP) removal efficiencies(20 ~ 37%) than group of LID facility designed on WQF. SA/CA graph was drawn for evaluation of design volume adequacy based on rainfall monitoring data. In this SA/CA graph, coefficient of determination show over 0.5 in all parameter, especially, Flow and TP were show over 0.95. And, 'SA/CA & L/CA' graph considering difference of structure mechanism in LID facility suggested in this research was confirmed that improved coefficient of determination in flow, TSS and TP than SA/CA graph. According to this research results, feasibility of applying 'SA/CA & L/CA' graph for evaluation of design volume adequacy in LID facility, and it is necessary to follow up research for generalization and normalization.

A Comparative Study on the Effect of Tamping Materials on the Impact Efficiency at Blasting Work (발파작업 시 충전매질에 따른 발파효과 비교 연구)

  • Bae, Sang-Soo;Han, Woo-Jin;Jang, Seung-Yup;Bang, Myung-Seok
    • Journal of the Korean Geosynthetics Society
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    • v.21 no.2
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    • pp.57-65
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    • 2022
  • This study simulated the shock wave propagation through the tamping material between explosives and hole wall at blasting works and verified the effect of tamping materials. The Arbitrary Lagrangian-Eulerian(ALE) method was selected to model the mixture of solid (Lagrangian) and fluid (Eulerian). The time series analysis was carried out during blasting process time. Explosives and tamping materials (air or water) were modeled with finite element mesh and the hole wall was assumed as a rigid body that can determine the propagation velocity and shock force hitting the hole wall from starting point (explosives). The numerical simulation results show that the propagation velocity and shock force in case of water were larger than those in case of air. In addition, the real site at blasting work was modeled and simulated. The rock was treated as elasto-plastic material. The results demonstrate that the instantaneous shock force was larger and the demolished block size was smaller in water than in air. On the contrary, the impact in the back side of explosives hole was smaller in water, because considerable amount of shock energy was used to demolish the rock, but the propagation of compression through solid becomes smaller due to the damping effect by rock demolition. Therefore, It can be proven that the water as the tamping media was more profitable than air.

Prioritizing Themes Using a Delphi Survey on Patient Safety Theme Reports (환자안전 주제별 보고서의 주제 우선순위 설정: 델파이 조사를 통한 분석)

  • Park, Jeong Yun;Shin, Eun-Jung;Kim, Rhieun;Kim, Sukyeong;Park, Choon-Seon;Park, Taezoon;Choi, Yun-Kyoung;Heo, Young-Hee
    • Quality Improvement in Health Care
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    • v.28 no.1
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    • pp.45-54
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    • 2022
  • Purpose: The study aims to identify the theme list and priority criteria of patient safety theme reports in South Korea. Methods: The survey was conducted twice, and the importance of each criterion and theme was measured on a nine-point scale using the Delphi technique by a panel of 19 patient safety experts. The criteria included severity, universality, preventability, and organizational-social impact. Descriptive statistics such as frequency, percentage, mean, standard deviation, median, and interval quartile range were used to analyze the data. Results: The parameters were assigned a weighted average of 35% for severity, 20% for universality, 30% for preventability, and 15% for organizational-social impact, respectively. The final top three rankings were surgery safety, blood transfusion safety, and medication safety. In addition to expert opinion, for the theme that is selected based on the priority ranking, one to five sub-topics can be derived from the theme based on the priority ranking, societal demands, or the yearly priority list of patient safety incidents. Conclusion: It is recommended that the official patient safety center distribute the report in the form of a summary that can be utilized nationwide at medical institutions, government institutions, and other places. Updates, as well as accumulated theme reports, will serve as the baseline data for the proposal of the system and for the policy designed to implement and improve institutions' safety practices as a standard of domestic patient safety practice guidelines.

Examining the Impact of Corporate Capability, Human and Institutional Factors on SME Succession Intentions : The Moderating Effect of Business Scale (기업 역량 및 인적, 제도적 요인이 중소기업 승계 의도에 미치는 영향 : 매출액 규모의 조절효과)

  • Bae, Jung-sik;Chung, Byoung-gyu
    • Journal of Venture Innovation
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    • v.6 no.3
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    • pp.241-263
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    • 2023
  • Recently, the aging of SME managers has emerged as a major issue in business succession. The smooth succession of small and medium-sized enterprises (SMEs), which are the industrial base of Korea, is becoming an important issue for enhancing the vitality of the national economy, such as job creation, beyond mere discussion of inheritance. At this point, this study conducted an empirical analysis on the factors affecting corporate succession intention. As independent variables, corporate Capability consisting of employee competency, marketing competency, and digital competency, human factors such as managers, successors, and third-party stakeholders, and institutional factors such as legislation, taxation, and trust were set. In addition, the effect of adjusting the sales scale was verified. To this end, a survey was conducted targeting representatives who are currently running small and medium-sized enterprises (SMEs). The total number of valid questionnaires was 315. Based on this, an empirical analysis was conducted using the hierarchical regression method. The results of the empirical analysis are as follows. First, marketing competency and digital competency, managerial competency and successor competency, taxation and trust had a significant positive (+) effect on corporate succession intention. However, a significant influence relationship between the third stakeholder, employee competency, and corporate succession intention was not tested. Among the factors that have a significant impact, the size of the influence was in the order of taxation, successor competency, executive competency, trust, marketing competency, and digital competency. Second, the size of sales was found to moderate the relationship between the variables that had a significant effect on corporate succession intention, that is, management competency, successor competency, marketing competency, digital competency, taxation and trust, and corporate succession intention. Based on these research results, academic, practical, and institutional implications for smooth business succession are presented.

Sediment Unit Loads from Developing Areas during Storms (개발사업장에서의 강우시 토사 유출원단위 산정)

  • Kim, Cheol Min;Lee, Eun Ju;Lee, So Young;Kim, Young Chol;Kim, Lee Hyung
    • Journal of Wetlands Research
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    • v.10 no.1
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    • pp.59-68
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    • 2008
  • Three phases of development in construction projects (i.e. pre-development, construction and post construction) diversely effect the environment, hydraulics and ecosystem. Currently, the domestic environmental policy is in control of the various environmental hazards produced after completion of development operations. Nevertheless, with the enforcement of water pollution total amount management system, improving the water quality; also the water and ecosystem preservation law recommends enforcing the sediment management for development operations in order to lessen the negative impacts to the environment. Recently, the country is experiencing difficulties in various development project locations due to insufficiency of interpreting the fundamental data for sediment loss and miscalculation of soil loss unit loads of sediment. This research utilizes data from 2000 to 2005 discussing a total of 1,036 environment impact assessment projects gathered from various ministries and offices namely Ministry of Environment (MOE), Ministry of Agriculture, the Office of Forestry, and Ministry of Construction and Transportation. Moreover, quantity of sediment from high land agriculture reports involving contaminant discharge characteristic investigation previously did concerning old land agriculture and So-Yang lake non-point pollution source management area as well as management measured data from MOE. The findings of this study reveal that the highest soil loss rate occurred from mountain district for pre-development and post construction and sports facility during construction.

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Ovarian Transposition for Stage Ib Squamous Cell Cervical Cancer - Lack of Effects on Survival Rates?

  • Turan, A. Taner;Keskin, H. Levent;Dundar, Betul;Gundogdu, Burcu;Ozgul, Nejat;Boran, Nurettin;Tulunay, Gokhan;Kose, M. Faruk
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.1
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    • pp.133-137
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    • 2013
  • Background: To investigate the impact of ovarian transposition (OT) on survival rates of the patients with stage Ib squamous cell cervical cancer. Materials and Methods: Ninety-two subjects who underwent a radical hysterectomy including oophorectomy were evaluated. For nineteen (20.7%), OT was performed. Patients were divided into two groups, OT versus oophorectomy alone. The primary end-point of this study was to investigate the impact of OT on tumor recurrence rate and time, 5-year disease-free survival (DFS) and overall survival (OS). These comparisons were performed for subgroups including patients who received radiotherapy versus who did not. Statistical analyses were conducted using the Chi-square test, T-test and Mann-Whitney test. OS was examined using the Kaplan-Meier method. $P{\leq}0.05$ was considered to be statistically significant. Results: The median follow-up period was 89 months for OT and 81 months for the oophorectomy group (p>0.05). Both groups experienced similar recurrence rates (31.6% vs. 26.4%, p=0.181). The median duration from surgery to recurrence, and surgery to death were also similar between the groups (p>0.05). The 5-year DFS and OS rates were both 68.4% for the OT group, and 73.6% and 77.8% for the oophorectomy group (p=0.457 and p=0.307, respectively). While the 5-year DFS rate was not statistically significant between the OT and oophorectomy groups who did not receive radiotherapy (p=0.148), the 5-year OS rate was significantly higher in the oophorectomy group (95.4% vs 66.7%, respectively) without radiotherapy (p=0.05). The 5-year DFS and OS rates were statistically similar between the groups who received adjuvant radiotherapy (p>0.05). Conclusions: Ovarian transposition has not significantly negative effect on the survival rates when adjuvant radiotherapy will be applied, while 5-year OS may be less in OT group if radiotherapy is not mandatory.

Assessment of Climate Change Impact on Imha-Dam Watershed Hydrologic Cycle under RCP Scenarios (RCP 기후변화 시나리오에 따른 임하댐 유역의 미래 수문순환 전망)

  • Jang, Sun-Sook;Ahn, So-Ra;Joh, Hyung-Kyung;Kim, Seong-Joon
    • Journal of the Korean Association of Geographic Information Studies
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    • v.18 no.1
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    • pp.156-169
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    • 2015
  • This study was to evaluate the RCP climate change impact on hydrological components in the Imha-Dam watershed using SWAT(Soil and Water Assessment Tool) Model. The model was calibrated for six year(2002~2007) and validated for six year(2008~2013) using daily observed streamflow data at three watershed stations. The overall simulation results for the total released volume at this point appear reasonable by showing that coefficient of determination($R^2$) were 0.70~0.85 and Nash-Sutcliffe model efficiency(NSE) were 0.67-0.82 for streamflow, respectively. For future hydrologic evaluation, the HadGEM3-RA climate data by scenarios of Representative Concentration Pathway(RCP) 4.5 and 8.5 of the Korea Meteorological Administration were adopted. The biased future data were corrected using 34 years(1980~2013, baseline period) of weather data. Precipitation and temperature showed increase of 10.8% and 4.9%, respectively based on the baseline data. The impacts of future climate change on the evapotranspiration, soil moisture, surface runoff, lateral flow, return flow and streamflow showed changes of +11.2%, +1.9%, +10.0%, +12.1%, +18.2%, and +11.2%, respectively.

Non-parametric Trend Analysis Using Long-term Monitoring Data of Water Quality in Paldang Lake (장기 모니터링 자료를 이용한 팔당호 수질변화의 비모수적 추세분석)

  • Cho, Hang-Soo;Son, Ju-Yeon;Kim, Guee-Da;Shin, Myoung-Chul;Cho, Yong-Chul;Shin, Ki-Sik;Noh, Hye-Ran
    • Journal of Environmental Impact Assessment
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    • v.28 no.2
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    • pp.83-100
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    • 2019
  • This study, we conducted a non-parametric trend test (Seasonal Kendall tests, LOWESS) and Cross Correlation. We aimed to identify water quality trends using the weekly data for 9 variables (Water Temperature, EC, DO, BOD, COD, T-N, T-P, TOC and Chl-a) collected from 4 sites in the Paldang Lake from 2004.01 to 2016.12. According to the Seasonal Kendall test, Water temperature increased but EC, T-N and T-P decreased trend. LOWESS showed that BOD was gradually decreased from 2013 to 2016. but COD gradually increased between 2012 and 2016. As a result, it was confirmed that the period between 2012 and 2013 was a turning point in the increase of COD along with the decrease of BOD at all sites in Paldang Lake. Results of Cross Correlation showed that there was no time difference between all of Water variables and Sites. In this study, it is necessary to analyze the cause of the transition period and to monitoring the water quality more precisely for better water quality management in Paldang Lake.

A Study on the Effects of Job Crafting and Innovation Behavior on Organizational Commitment -Focusing on the moderating effect of knowledge sharing- (잡크래프팅과 혁신행동이 조직헌신에 미치는 영향에 관한 연구 -지식공유의 조절효과를 중심으로)

  • Kim, Mi-yeon;Seo, Young-Wook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.6
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    • pp.441-452
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    • 2021
  • This work verifies the effect of Job Crafting on organizational commitment through innovative actions, and analyzes the regulatory effect, by setting up knowledge sharing among members as factors that promote Job Crafting and Innovative Action. Depending on the level of knowledge sharing, the indirect effects of Job Crafting from organizational commitment of the members through innovative actions are expected to vary, and the controlled mediated effects are analyzed. Totally, 463 individuals were surveyed, including start-ups, small and medium-sized enterprises, public institutions, and large enterprise workers. The hypothesis was subsequently verified through analysis by applying SPSS 18.0 and SPSS Process Macro. Our results reveal that Job Crafting has a positive impact on the innovation behavior of the members. Secondly, a higher level of knowledge sharing had a greater positive outcome in the member's innovation behavior. Third, all innovative actions positively impacted the organizational commitment of the members. The fourth notable point was that innovation behavior imparted only a moderate impact on the association between Job Crafting and Organizational Commitment. Finally, it was determined that there was no significance in the controlled mediated effect of knowledge sharing on the indirect effects of Job Crafting affecting organizational commitment through innovative actions. Based on the data verifying the hypothesis, we present here the theoretical and practical implications of this study.

RANS simulation of secondary flows in a low pressure turbine cascade: Influence of inlet boundary layer profile

  • Michele, Errante;Andrea, Ferrero;Francesco, Larocca
    • Advances in aircraft and spacecraft science
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    • v.9 no.5
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    • pp.415-431
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    • 2022
  • Secondary flows have a huge impact on losses generation in modern low pressure gas turbines (LPTs). At design point, the interaction of the blade profile with the end-wall boundary layer is responsible for up to 40% of total losses. Therefore, predicting accurately the end-wall flow field in a LPT is extremely important in the industrial design phase. Since the inlet boundary layer profile is one of the factors which most affects the evolution of secondary flows, the first main objective of the present work is to investigate the impact of two different inlet conditions on the end-wall flow field of the T106A, a well known LPT cascade. The first condition, labeled in the paper as C1, is represented by uniform conditions at the inlet plane and the second, C2, by a flow characterized by a defined inlet boundary layer profile. The code used for the simulations is based on the Discontinuous Galerkin (DG) formulation and solves the Reynolds-averaged Navier-Stokes (RANS) equations coupled with the Spalart Allmaras turbulence model. Secondly, this work aims at estimating the influence of viscosity and turbulence on the T106A end-wall flow field. In order to do so, RANS results are compared with those obtained from an inviscid simulation with a prescribed inlet total pressure profile, which mimics a boundary layer. A comparison between C1 and C2 results highlights an influence of secondary flows on the flow field up to a significant distance from the end-wall. In particular, the C2 end-wall flow field appears to be characterized by greater over turning and under turning angles and higher total pressure losses. Furthermore, the C2 simulated flow field shows good agreement with experimental and numerical data available in literature. The C2 and inviscid Euler computed flow fields, although globally comparable, present evident differences. The cascade passage simulated with inviscid flow is mainly dominated by a single large and homogeneous vortex structure, less stretched in the spanwise direction and closer to the end-wall than vortical structures computed by compressible flow simulation. It is reasonable, then, asserting that for the chosen test case a great part of the secondary flows details is strongly dependent on viscous phenomena and turbulence.