• Journal of Service Research and Studies
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• v.11 no.2
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• pp.118-130
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• 2021

This study designs and validates a greenhouse complex environmental control algorithm with a multi-phase processing scheme that can combine and control actuators according to the degree of change in the greenhouse environment. The composite environmental control system is a system in which the complex environmental controller analyzes the information detected by sensors and operates appropriately actuators to maintain the crop growth environment. A composite environmental controller directs control devices driving actuators through a composite environmental control algorithm, which calculates the values necessary for the operation of the control devices. Most existing algorithms carry out control procedures on a single phase by iteration cycle, which can cause abnormal changes in the greenhouse environment due to errors in output. The proposed algorithm distributes control procedures over multiple phases: environmental control, environmental control, and device operation, and every iteration cycle, detects environmental changes in the environmental control phase first, and then combines control devices that can control the environment in the environmental control phase, and finally, performs the controls to derive the actuators in the device operation phase. The proposed algorithm is designed based on the analysis of the relationship between greenhouse environmental elements and control devices deriving actuators. According to verification analysis, the multi-phase processing scheme provides room to modify or supplement the setting value and enables the control devices to reflect changes in the associated environmental components.

• Journal of the Korea Safety Management & Science
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• v.6 no.4
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• pp.195-213
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• 2004

This paper deals with an efficient and effective method on measuring, monitoring and evaluating safety and environmental performances of a process using SPC control charts. We propose 7 safety control charts as a tool to monitor hazard dendritics, and we propose 15 environment control charts to monitor pollution emissions. We also propose useful guidelines that SPC(Statistical Process Control) control charts can be used for safely and environmental monitoring.

• Journal of the Korean Home Economics Association
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• v.43 no.8 s.210
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• pp.99-114
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• 2005

The aim of this study was to estimate the effects of an early childhood environmental education program developed on the basis of relationships among preschoolers' knowledge, emotional attitude, and perceived behavior control of environmental pollution on their knowledge, emotional attitude, perceived behavior control, and behavioral intention. A total of 146 five-year-old preschoolers from eight child-care centers in Seoul and Kyoungki Province participated in this study. The following are the main results of this study. first, the higher the level of knowledge the preschoolers had, the more negative emotional attitude they displayed. Furthermore, the more negative emotional attitude they displayed, the higher the level of perceived behavior control they had. On the contrary, the relationships between knowledge and perceived behavior control varied with exposure situation to environmental pollution. Second, after the environmental education program was administered to the experimental group, the preschoolers from experimental group exhibited more knowledge, more negative emotional attitude, higher perceived behavior control and more active behavioral intention towards environmental pollution than those in the control group.

• Journal of Biosystems Engineering
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• v.24 no.5
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• pp.415-424
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• 1999

This study was conducted to assess performances of the developed environmental control systems under various seasons of Korea. In all trials for the environmental control systems, the manure pit ventilation system in the windowless pig-housing with partly slatted floor was used. Consequently, under all seasons of Korea, the complex environmental control systems could comfortably maintain the indoor temperature (14.8~27.2$^{\circ}C$) , concentrations of noxious gases (CO2 gas : 631~1,874ppm, NH3 gas : 0.3~3.2ppm), air velocity (0.11~0.23m/s), air movement, and so on. Therefore, the performances of the complex environmental control systems were evaluated as proper as the intended.

• Journal of environmental and Sanitary engineering
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• v.7 no.2
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• pp.53-68
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• 1992

Since 1962, Korea has made a remarkable progress with continuous success of Five-Year Economic Development Plans. Over the last 30 years, Korea has achieved a fast growth in various industries including heavy industry and chemical industry with rapid urbanization at the same time. The fast industrialization and urbanization brought about huge amount of hazardous/toxic substances and wastes. The environmental pollution problems have now emerged from regional concerns to overall social issues accordingly. The situation has come to a point where pollution control and environment preservation have become one of the nation's major policies. Following the recent Earth Summit of UNCED Conference held in Riode Janeiro in June 1992, where the topic was environmentally sound and sustainable development, awareness upon the importance of environmental preservation has been heightened globally, The environmental issues will gradually influence the international society more and more, politically as well as economically, The environmental pollution control industry in Korea started in the early 70's with the development of the nation's industrialization, As the people's awareness on pollution increases and environmental laws and enforcing regulations were established, demand for pollution control began to increase. The environmental pollution control business came to be recognized as an independent industry in the mid'70's. It should be evaluated properly that over the last 30 years, the Korean pollution control industry has supplied locally manufactured pollution control facilities to the increasing local demand. Concerning the quality and customer satisfaction, however, there are still many aspects which need to be improved compared with those of advanced countries. Although the start of the pollution control industry in Korea is just 10 to 15 years behind the advanced countries such as Japan and European countries, current gap in the environmental technology is rather considerable. And, studies should be made to find out the reasons for the current technology gap, and therefore, to implement solutions to improve the technology and competitiveness of the environmental pollution control industry in Korea.

• Journal of Korean Society on Water Environment
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• v.26 no.5
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• pp.768-774
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• 2010

This study was conducted to provide a technical solution to treat effectively perchlorate from inorganic wastewater of zinc smelting. Despite an inhibition dissolved inorganic substances in the wastewater discharged from zinc smelting has demonstrated with the activity of microbes, biological treatment technology could reduce perchlorate to a satisfactory level under such stressful conditions. It was found that either conductivity or $SO{_4}^{2-}$ concentration of the wastewater was able to be used as the adequate index and the values were $2,450{\mu}S/cm$ and 1,200 ppm respectively. When $SO{_4}^{2-}$ increased from 0 to 16,000 ppm (conductivity : $428{\rightarrow}24,800{\mu}S/cm$), perchlorate biodegradation rate was reduced due to 1/10 times from 0.0365 to 0.0033/h, however, most of perchlorate was removed under the condition of hydraulic retention time (HRT) at 0.5day and mixed liquor volatile suspended solid (MLVSS) at 2,000 ~ 3,000 ppm.

• Journal of Environmental Health Sciences
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• v.46 no.5
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• pp.599-609
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• 2020

Objectives: Coronavirus disease 2019 (COVID-19) first emerged in December 2019 in Wuhan, China, and has rapidly become a global pandemic with over 26.4 million confirmed cases and approximately 871,000 fatalities worldwide as of this writing. In the Republic of Korea, disease clusters frequently occurred in long-term care hospitals where the majority of residents are elderly with underlying medical conditions. Despite the fact that public health authorities and local community health centers have put tremendous efforts into preventing the spread of disease, positive cases have continued to occur. Thus, the Korea Centers for Disease Control & Prevention rapid response team decided to conduct an environmental investigation of a long-term care hospital to identify whether environmental contamination has remained and contributed to the spread of COVID-19. Methods: An environmental investigation was conducted at Hospital A. The characteristics of the facility and its HVAC system were assessed by checking the layout and interviewing the people in charge. A total of 64 surface samples were collected from areas of concern, including patient rooms, toilets, elevators, and nurses' station. These samples were tested by a regional health and environmental research institute using real-time reverse transcription polymerase chain reaction. Results: All samples from Hospital A were confirmed to be negative. Through interviews with high-level personnel at the regional community health center, we found that extensive disinfection is frequently performed on potentially contaminated areas in Hospital A in accordance with government guidelines. Conclusion: The environmental control measures implemented in Hospital A had been sufficient for mitigating the risk of further infection, suggesting that such measures may also be effective for other long-term health care facilities.

• Food Science and Preservation
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• v.4 no.2
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• pp.101-113
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• 1997

Temperature, relative humidity and ventilation are closely related one another, and they are the main factors to be controlled for the environmental control system of a storage facility. Conventional environmental control systems do not consider the interrelationship between temperature, relative humidity and ventilation, which results in low performance and high energy consumption. To overcome the inefficiency of the conventional ones, it was developed an on-off control system based on the interrelationship between the factors. The usefulness of the system was illustrated with the results produced by a set of experiments in a real world.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2009.04a
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• pp.193-198
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• 2009

This study focuses on building an effective environmental control system for the ubiquitous housing environment. In order to build an effective environmental control system that will provide a comfortable, pleasant, and convenient environment for residents, information on how people cognize the indoor and outdoor environmental conditions, information on human beings, and information of the space should be studied. Also more studies need to be done in which method would be the best way to integrate these informations that would affect the users in the most positive way. The current environmental control system only carries the information on providing separate information of environmental factors such as light, temperature, humidity, heat, and sound. However, it is difficult to understand the energy efficiency of an architectural element through this system. Therefore, this study proposes an energy monitoring system utilizing spatial information.

• Hwankyungkyoyuk
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• v.17 no.1
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• pp.90-100
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• 2004

This study has the goal to modify ‘Investigating and Evaluating Environmental Issues and Actions’(IEEIA) instruction in the sense of Korean ecological sociocultural characteristics and ‘ecology and environment' curriculum and to assess the effects of modified IEEIA instruction on responsible environmental behavior and associated variables in high school student. A modified pre- and post-test nonequivalent control group design was utilized with 4 intact classes from J-high school at Seo-cheon, Chungcheongnamdo. Pre- and post-test data were collected on the following variables: responsible environmental behavior, knowledge of and skill in using environmental actions strategies, in-depth knowledge about issues, and locus of control. Analysis of t-test was used to compare pretest with posttest means of treatment group and control group. In treatment group, statistically significant differences between pretest and posttest were found with all variables. The treatment was found to be more effective than the control in increasing the variables of responsible environmental behavior, knowledge of and skill in using environmental actions strategies, and locus of control.