• Environmental Engineering Research
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• v.16 no.3
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• pp.113-119
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• 2011

This study traces the origin, evolution, and current state-of-the-art of engineering-oriented water-quality management and modeling. Three attributes of polluted water underlie human concerns for water quality: rubbish (aesthetic impairment), stink (ecosystem impairment), and death (public health impairment). The historical roots of both modern environmental engineering and water-quality modeling are traced to the late nineteenth and early twentieth centuries when European and American engineers worked to control and manage urban wastewater. The subsequent evolution of water-quality modeling can be divided into four stages related to dissolved oxygen (1925-1960), computerization (1960-1970), eutrophication (1970-1977) and toxic substances (1977-1990). Current efforts to integrate these stages into unified holistic frameworks are described. The role of water-quality management and modeling for developing economies is outlined.

• Journal of the Korean Professional Engineers Association
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• v.26 no.3
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• pp.69-79
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• 1993

This paper explains about general considerations and project management for a State of the Art utility supervisory systems. [1] The implementation and management of a supervisory system design project requires both a dedication of resources and application of good communications in order to be suc-cessful. [2] Success is on time delivery of a system to a satisfied customer at the proposal cost, [3] The recent experience of a company plus the collected comments from a number of ex-perienced control center project management provide a guideline for the company who is considering such a project. The Comments reflect typical situations or decision points faced by the project Manage.[2] This paper also attempts to help engineers in the task of specifying buying, and instal-ling a supervisory system[1]

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.12
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• pp.88-96
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• 2015

This paper describes a new method for enhancing the accuracy of network analysis applications in energy management systems. Topology processing, state estimation, power flow analysis, and contingency analysis play a key factor in the stable and reliable operation of power systems. In this respect, the aim of topology processing is to provide the electrical buses and the electrical islands with the actual state of the power system as input data. The results of topology processing is used to input of other applications. New method, which includes the topology error analysis based on inconsistency check, coherency check, bus mismatch check, and outaged device check is proposed to enhance the accuracy of network analysis. The proposed methodology is conducted by energy management systems and the Korean power systems have been utilized for the test systems.

• Journal of Power Electronics
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• v.10 no.2
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• pp.210-217
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• 2010

This paper introduces a lithium ion battery management system (BMS) for the STSAT-3 satellite. The specifications of a lithium ion battery unit are proposed to supply power to the satellite and the overall electrical and mechanical designs for a lithium ion battery management system are presented. The structural simulation results will be shown to confirm the behavior of both the BMS and the cells.

• Journal of Korean society of Dental Hygiene
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• v.11 no.4
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• pp.547-556
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• 2011

Objectives : The purpose of this study was to examine the relationship between the infection control education experiences of dental hygienists and the state of their infection control. Methods : The subjects in this study were the dental hygienists who worked in Seoul. The relationship of their infection control education experiences to their gender, marital status, academic credential, workplace, length of service, infection control implementation, experience of being exposed to infection, way of coping with it, hand washing, use of personal protection devices and equipment management was analyzed. Results : It is found that the variable to affect the state of infection control was educational experiences about handpiece water pipe management, ultrasonic scaler water pipe management and three-way syringe water pipe management. Conclusions : Dental hygienists who are one of major dental personnels should receive systematic education on infection control to acquire accurate knowledge to ensure the successful prevention of cross infection.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.3
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• pp.1345-1362
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• 2019

Most active queue management algorithms manage network congestion based on the size of the queue but ignore the network environment which makes queue size change. It seriously affects the response speed of the algorithm. In this paper, a new AQM algorithm named CT-AQM (Change Trend-Adaptive Queue Management) is proposed. CT-AQM predicts the change trend of queue size in the soon future based on the change rate of queue size and the network environment, and optimizes its dropping function. Simulation results indicate that CT-AQM scheme has a significant improvement in loss-rate and throughput.

• Advances in Energy Research
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• v.8 no.3
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• pp.145-153
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• 2022

Recent concerns about rising fuel prices and greenhouse gas emissions have focused attention on alternative energy sources, particularly in the transport sector. Transportation consumes 40% of overall fuel usage. As a result, a growing majority of researches on Electric Vehicles (EVs) and their Energy Management Systems (EMS) have been done. In order to enhance the performance and to meet the needs of drivers, more information regarding the EMS is needed. A new Energy Management System is proposed using a FOPID controller. To put the concept into practice, state equations are utilised. The fifth-order state-space model under study is a linked model with several inputs and outputs and the transfer matrices are calculated for decoupling the system. Utilizing these transfer matrices to decouple the system and FOPID controller is used to tune the system. The tuned parameters are minimized using a Particle Swarm Optimization (PSO) approach with Integral Time Absolute Error (ITAE) as the goal. When the suggested FOPID system's results are compared to those of PID-controlled systems, a sizable improvement is observed, which is explained by the results.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.179-187
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• 2022

The project performances can be measured in terms of meeting the project schedule, budget, and conformance to functional and technical specifications. Numerous studies have been conducted to examine the causes and effects of change orders for both vertical and horizontal construction, respectively. However, these studies mainly focus on a single project type, so this paper examines the impact of change order for cost growth and schedule overruns using four different building types to close the gap in the change order research area. A total of 211 building projects are collected from four building types: healthcare, residential, office, and education. Statistical analyses using ANOVA tests and linear regression models are used to examine the created metric $CO/day on the cost and schedule impacts. The results found that mean $CO/day values were not statistically different among building types, and that the sum of change orders is a statistically significant predictor of $CO/day. The results will help project stakeholders mitigate the negative change orders effects can be a challenge for project managers and researchers alike.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.42-46
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• 2013

California's heartland, the Great Central Valley, is one of the most productive agricultural regions in the world. However for many years the valley has been struggling with a broad range of social, economic, and environmental challenges. Some significant concerns include water resources, air pollution, poverty rates, housing issues, etc. Another strike against the valley is the relative reluctance to embrace widespread sustainable building practices. This paper discusses the long-term and profound impact of the built environment has on the aforementioned socioeconomic and environmental issues facing the valley. It reviews exemplary practices in other states and regions regarding policy-making and regulation in the building industry as well as sustainable community development. The paper further explores viable options specifically for the Fresno metropolitan area (the largest in the Central Valley) to combat its unique multifaceted challenges.

• Korean Journal of Adult Nursing
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• v.16 no.3
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• pp.442-451
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• 2004

Purpose: The purpose of this study was to examine the relationship between perceived health state, personality, situational barrier, health promoting behavior, to provide the basic data for health promoting intervention. Method: This study was designed as a descriptive correlation study. Data were 396 undergraduate students of one university in Chung-Buk. The instruments for this study were the modified health promoting behavior scale developed by Bak, Insuk(1995), and the modified perceived health state scale developed by Im, Meeyoung (1998), the modified personality scale developed by Park, Youngbae(1998), the modified situational barrier scale developed by Im, Meeyoung(1998). Result: The results of this study showed that the mean score for perceived health state 2.72, personality 3.35, situational barrier 2.72 and health promoting behavior 2.67. The health promoting behavior categories, scores for 'sanitary life'(3.08), 'self-actualization and interrelationship'(2.93) were higher than the mean score, whereas scores for 'healthy diet'(2.64), 'rest and sleep'(2.62), 'exercise and stress management'(2.49), and 'diet management' (2.25) were lower than the mean score. This study revealed the negative correlation between perceived health state, personality, situational barrier and health promoting behavior in undergraduate students. Conclusion: Perceived health state accounted for 16% and personality accounted for 21.3% of the variance in health promoting behavior in students. Therefore, health promoting programs that increase health state and personality should be developed to promote health behavior and to diminish situational barrier for students in Korea.