• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.169-169
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• 2023

Most distributed water is not used effectively due to water loss occurring in pipe networks. These water losses are caused by leakage, typically due to high water pressure to ensure adequate water supply. High water pressure can cause the pipe to burst or develop leaks over time, particularly in an aging network. In order to reduce the amount of leakage and ensure proper water distribution, it is important to apply pressure management. Pressure management aims to maintain a steady and uniform pressure level throughout the network, which can be achieved through various operational schemes. The schemes include: (1) installing a variable speed pump (VSP), (2) introducing district metered area (DMA), and (3) operating pressure-reducing valves (PRV). Applying these approaches requires consideration of various hydraulic, economic, and environmental aspects. Due to the different functions of these approaches and related components, an all-together optimization of these schemes is a complicated task. In order to reduce the optimization complexity, this study recommends a sequential optimization method. With three network operation schemes considered (i.e., VSP, DMA, and PRV), the method explores all the possible combinations of pressure management paths. Through sequential optimization, the best pressure management path can be determined using a multiple-criteria decision analysis (MCDA) to weigh in factors of cost savings, investment, pressure uniformity, and CO₂ emissions. Additionally, the contribution of each scheme to pressure management was also described in the application results.

• Journal of Distribution Science
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• v.20 no.4
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• pp.65-75
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• 2022

Purpose: Environmental pollution problems have become more and more serious, how to effectively protect the environment has become a hot spot of concern to all sectors of society. The way to solve this problem is environmentally friendly management. However, theoretical perspectives and research frameworks of existing research on environmentally friendly management are still unclear. This study aims to examine how the CEO's beliefs for SMEs of Chinese distribution industry affect the environmentally friendly management based on institutional theory. Research design, data, and methodology: This paper collected data from 215 SMEs in China distribution industry and conducted a series of data analysis and hypothesis testing based on an institutional theory perspective using Amos and SPSS to verify the effects of regulatory pressure, normative pressure, and imitation pressure on firms' environmentally friendly management. Results: Through the analysis, this paper tests that normative pressure and imitative pressure have a positive effect on CEO's beliefs. However, regulatory pressure did not have a significant effect on beliefs of CEO. Meanwhile, the degree of CEO's beliefs has a positive effect on environmentally friendly management in Chinese distribution SMEs. Conclusions: Theoretical contributions, practical implications, and future research directions are discussed.

• Korean Journal of Human Ecology
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• v.5 no.1
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• pp.15-31
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• 1996

The purpose of this study is to investigate the relationship to the life-style, perceived time pressure and time management strategies of married women. The research issues are as follow : 1. How are Life-styles influence to the perceived time pressure according to employment status of marraged women? 2. How are life-styles influence to the time manegement strategies according to employment status of marraged women? 3. How much are the effect of life-style, perceived time pressure and the rest of variable on the time management strategies of marraged women? For the purpose of this study, 585 questionnaire were distributed to marraged women living in pusan. The data were analyzed by statistical methods such as Pearson's correlation, percentage, factor analysis, and regression analysis. The significant results are as follow : 1. According to the employment status, there were several differences among those life-styles which are influencing to the perceived time pressure. 2. According to the employment status, there were differences among those life-styles which are influencing to the time management strategies. 3. Independent variables about the time management strategies of married women showed life-style(B=.46), age(B=-.18), income(B=.15), perceived time pressure(B=.12). education level(B=.07). The results of this study can be attributed to develop the efficient strategy of reducing perceived time pressure of marraged women.

• Journal of Korean Tunnelling and Underground Space Association
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• v.18 no.1
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• pp.53-60
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• 2016

This study analyzed a monitoring data, based on the initial limit values of monitoring in subway, of earth pressure and pore water pressure. The data is obtained from 8 sections of the Seoul metropolitan subway line No 6, 7 and 9 in about 5 years. Also, a research is performed to set up the limit values of management monitoring, which will be applied to management monitoring in tunnel, through comparing the limit values of overseas management monitoring data and that of domestic management monitoring data. And the result obtained from comparison show that the safety phase is 60% of allowable pressure, the attention phase is 80% of allowable pressure and the precision analysis phase is 100% of allowable pressure. Also, we presented a method of management monitoring by the absolute value which can be easily applied easily in practical affairs.

• Journal of Korean Academy of Nursing
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• v.45 no.4
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• pp.576-586
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• 2015

Purpose: The purpose of this study was to develop a self-management program applying Dongsasub training based on self-efficacy theory, and to verify the program effectiveness on self-esteem as well as self-efficacy, self-management behaviors, and blood pressure. Methods: The study design was a non-equivalent, pre-post controlled quasi-experiment study. Thirty-eight patients aged 65 and older from a senior welfare center in Seoul participated in this study (20 patients in the experimental group and 18 patients in the control group). The self-management program applying Dongsasub training consisted of eight sessions. After development was complete the program was used with the experimental group. Outcome variables included self-efficacy, self-esteem, self-management behaviors measured by questionnaires, and blood pressure measured by electronic manometer. Results: Self-efficacy (t=2.42, p=.021), self-esteem (t=2.57, p=.014) and self-management behaviors (t=2.21, p=.034) were significantly higher and systolic blood pressure (t=-2.14, p=.040) was significantly lower in the experimental group compared to the control group. However, diastolic blood pressure (t=-.85, p=.400) was not significantly different between the two groups. Conclusion: The results indicate that the self-management program applying Dongsasub training can be used as a nursing intervention in community settings for improving self-management behaviors for older adults with hypertension.

• Journal of the Korean Society of Costume
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• v.58 no.10
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• pp.112-122
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• 2008

The purposes of this study were to verify how internalization of ideal beauty stereotype and objectified body consciousness by sociocultural pressure factors had an influence on body satisfaction and examine the relation between body satisfaction and appearance management behavior. To achieve the purposes, a survey was conducted to 419 female adults, whose ages were from 18 to 29. Data were analyzed by structure equation modeling of Amos 4.0 and SPSS 10.0 program. The results of this study were summarized as follows: First, there were significant differences in sociocultural pressure, objectified body consciousness, internalization of ideal beauty stereotype, body satisfaction and appearance management behavior variables. Second, sociocultural pressure factors such as, family, friends, media had a positive effect on objectification that female adults saw themselves from the viewpoint of a watcher; when females more highly recognized sociocultural pressure like family, friends and media, their satisfaction with body became lower. Third, when females had high tendency of objectification and high body satisfaction, they affirmatively managed their appearance.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.1
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• pp.1-14
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• 2023

This study is a leading case of empirical analysis of whether, when corporate stakeholders (government, investors, customers, managers, employees) put pressure on companies for ESG management, it affects the introduction and implementation of ESG activities (environmental, social, governance) and affects business performance. As for the research method, a sustainability report was published, and a web survey of Korea Research Inc. was conducted from May 10 to May 20, 2022 targeting ESG management managers of 192 companies, and analyzed through the PLS structural equation model. As a result of the study, it was found that the introduction and execution of ESG is closely influenced by the pressure from the government, investors, managers, and employees, and in particular, the internal pressure of current managers and executives and employees has a great impact on the introduction and implementation of environmental, social, and governance activities. In particular, although external pressure also has some influence, it is practical to suggest that strong internal pressure is necessary for continuous activities and performance. And, methodologically, the main activity indicators of the GRI Reporting Guidelines, which are the most representative ESG management indicators, were developed as a questionnaire, and reliability, validity, and model fit were secured through comparison with indicators of multiple systems and expert reviews. The limitations of this study are that more in-depth analysis by industry or size is possible when ESG management is mature and sufficient samples are secured, and complex ESG pressure factor modeling is possible when more diverse stakeholders are added.

• Journal of the Korean Society of Safety
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• v.34 no.4
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• pp.6-14
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• 2019

There are about 38,977 CNG cars and 247 natural gas vehicle charging stations in operation in order to improve the urban air environment. With the introduction of natural gas vehicles, the atmospheric environment, which was the main cause of air pollution in the metropolitan area, was remarkably improved. However, unlike these positive effects, CNG bus accidents, which occurred more than 10 times since 2005, have caused concern among the majority of citizens using public transportation. It is necessary to make a judgment on the feasibility and future direction of CNG pressure vessel safety management that can safeguard the safety of CNG pressure vessel at the time of starting. In this study, we investigates production and use of CNG vessel, the current status of safety management of CNG bus transportation companies & charging stations and then proposes measures to prevent accident recurrence and safety management based on the actual situation investigation and analysis.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.04a
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• pp.251-254
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• 2008

The fact that the major cases of life casualties are from smoke in the fire accidents and the expected steep increase of skyscrapers, huge spaces, multiplexes and huge scaled underground spaces demand establishment of efficient smoke countermeasure. The field experiments on two high buildings of 20 stories and 21 stories are carried out to evaluate the field performance of pressure differential systems for smoke management and the results of experiments are presented.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.7
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• pp.403-412
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• 2020

The main purpose of this paper is to explore how green supply chain management (GSCM) and its evaluative factors have affected green supply chain management practice and performance in industrial zone. This study proposes a structural equation model of the relationships among four factors: internal awareness (IA); suppliers' pressure (SP); customers' awareness (CA); and regulations pressure (RP) and their effect on GSCM practice (PA) and GSCM performance (PE). We used a survey questionnaire to elicit perceptions/opinions about GSCM from three level of managers of 322 companies in Bac Ninh Province's industrial zones, Vietnam. PLS-SEM 3.0 software was applied to analyze and verify the gathered data, and the proposed hypothesis model. The results of path analysis show that internal awareness and customers' awareness are positively related to the GSCM practice and GSCM performance. However, suppliers' pressure and regulations pressure just impacted on GSCM practice. As a result, the testing of the relationship between GSCM practice and GSCM performance has been verified and supported. The findings of this study can help manager of companies in industrial zone understand the structure of GSCM, associate with the green supply chain management practice and green supply chain management performance, and be successful in green management organizations.