• Journal of Bio-Environment Control
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• v.15 no.1
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• pp.1-7
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• 2006

This study was conducted to develop a system and an control algorithm for control the environment of a plant factory. The greenhouse control system for environmental control was largely composed of a computer and a PLC. The screen of control program was composed of a greenhouse figure which was included machinery and equipments for greenhouse, the graph of environmental factors of inside greenhouse and the image of greenhouse. In order to reduce temperature change, the operation time of ventilation window was changed by 3 stage according to difference between a target and present temperature. When is heating, a temperature variation was shown to be $16.7{\pm}0.8^{\circ}C$. When is cooling, a temperature variation was shown to be $23.1{\pm}0.6^{\circ}C$. When is humidifing, a humidity variation was shown to be $39.3{\pm}1.6^{\circ}C$ %RH. An environmental control system and a control algorithm were proved that it was shown a good performance in a control accuracy. So a computer control system should be adapted to a control system of a greenhouse and a plant factory.

• Archives of Pharmacal Research
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• v.4 no.2
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• pp.141-153
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• 1981

In Japan, rapid development of economy during the 1960s caused the problems of environmental pollution, and hazards occurred in many places of Japan, water pollution had increased in those days, and water used for drinking, agriculture, fishing, industry nd recreation were demaged. By water-born diseases like as Minamata and Itai-Itai diseases, many patients suffered as you know well. In 1967, Japanese Government set up Basic Law for Environmental Pollution Control and in 1970 Water Pollution Control and in 1970 Water Pollution Control Law.

• Smart Structures and Systems
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• v.3 no.3
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• pp.385-403
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• 2007

The effectiveness of the newly developed smart passive control system employing a magnetorheological (MR) damper and an electromagnetic induction (EMI) part for seismic protection of base isolated structures is numerically investigated. An EMI part in the system consists of a permanent magnet and a coil, which changes the kinetic energy of the deformation of an MR damper into the electric energy (i.e. the induced current) according to the Faraday's law of electromagnetic induction. In the smart passive control system, the damping characteristics of an MR damper are varied with the current input generated from an EMI part. Hence, it does not need any control system consisting of sensors, a controller and an external power source. This makes the system much simpler as well as more economic. To verify the efficacy of the smart passive control system, a series of numerical simulations are carried out by considering the benchmark base isolated structure control problems. The numerical simulation results show that the smart passive control system has the comparable control performance to the conventional MR damper-based semiactive control system. Therefore, the smart passive control system could be considered as one of the promising control devices for seismic protection of seismically excited base isolated structures.

• Journal of Environmental Health Sciences
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• v.49 no.4
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• pp.179-182
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• 2023

The Chemical Substances Control Act has been legislated to counter the risks posed by chemical substances to public health and the environment, but a number of small- and large-scaled incidents related to hazardous chemicals continue to occur every year. The Korean Ministry of Environment takes legal responsibility for prevention, preparedness, and response to nationwide chemical accidents under the Chemical Substances Control Act. The determination of chemical accidents that occur during hazardous chemical handling processes is based on the Article 2 (Definitions) of the law and the administrative criteria for judgement of chemical accidents. However, there are certain ambiguities in the scientific basis for determining chemical accidents under the current regulations. Whether or not a chemical accident has a direct influence on penalties and administrative measures for a workplace where an accident occurred, it is necessary to find reasonable criteria for determining chemical accident based on legal and scientific evidence.

• Journal of Environmental Science International
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• v.17 no.4
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• pp.365-374
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• 2008

The purpose of this study was to clarify the effects of the environmental education system focusing on the knowledge, attitude and practice in relation to environmental education to the students in Mokpo middle school. The study is accomplished by the survey which includes a total of 268 inquiry lists sampled from four groups of the middle school, one of which composing of two middle schools having the environmental curriculum, hereafter referred as 'the case group' and the other group of two middle schools without the curriculum, hereafter referred as the 'the control group'. From the results of the average scores on the environmental knowledge, attitude and practice between the two groups, the case group showed better knowledge scores than the control group (p<0.05). The case group with environmental education were relatively high to the control group without environmental education to the attitude(p<0.05), and did not showed signifiant differences in the environmental practice. From the results of stepwise multiple regression analysis, the factor affecting the environmental knowledges was the interest in the environment problems ($R^2=0.130$), economic status, academic achievement and the necessity of environment conservations in order. The factor most affecting to environmental attitude and practice were the interest in environmental problems of the parents.

• Tuberculosis and Respiratory Diseases
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• v.79 no.4
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• pp.234-240
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• 2016

Transmission of tuberculosis (TB) is a recognized risk to patients and healthcare workers in healthcare settings. The literature review suggests that implementation of combination control measures reduces the risk of TB transmission. Guidelines suggest a three-level hierarchy of controls including administrative, environmental, and respiratory protection. Among environmental controls, installation of ventilation systems is a priority because ventilation reduces the number of infectious particles in the air. Natural ventilation is cost-effective but depends on climatic conditions. Supplemented intervention such as air-cleaning methods including high efficiency particulate air filtration and ultraviolet germicidal irradiation should be considered in areas where adequate ventilation is difficult to achieve. Personal protective equipment including particulate respirators provides additional benefit when administrative and environmental controls cannot assure protection.

• Environmental and Resource Economics Review
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• v.1 no.1
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• pp.115-149
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• 1991

In evaluating current environmental protection policy, economists often note that current regulations are more costly than necessary to meet environmental quality standards. While the a priori case can be made that current regulatory approaches entail higher-than-necessary costs to attain environmental standards, there is relatively little empirical evidence to support this claim in Korea. The purpose of this analysis is to supply some of the missing evidence by presenting the results of one study that assesses some of the potential savings associated with implementing economic, rather than command-and-control regulatory approaches to abate one type of air pollution in one region, in Korea, Specifically, the analysis examine the costs of meeting a long-term standard for TSP under the alternative control strategies for stationary sources of TSP in Ulsan Industrial Complex region. The alternative strategies that are considered are current command-and-control and various marketable permit designs. The analysis shows that the most efficient policy of emissions control is economic approaches, supporting results of previous empirical studies conducted in other countries.

• Journal of Microbiology
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• v.43 no.spc1
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• pp.85-92
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• 2005

An early step in the pathogenesis of non-typhoidal Salmonella species is the ability to penetrate the intestinal epithelial monolayer. This process of cell invasion requires the production and transport of secreted effector proteins by a type III secretion apparatus encoded in Salmonella pathogenicity island I (SPI-1). The control of invasion involves a number of genetic regulators and environmental stimuli in complex relationships. SPI-1 itself encodes several transcriptional regulators (HilA, HilD, HilC, and InvF) with overlapping sets of target genes. These regulators are, in turn, controlled by both positive and regulators outside SPI-1, including the two-component regulators BarA/SirA and PhoP/Q, and the csr post-transcriptional control system. Additionally, several environmental conditions are known to regulate invasion, including pH, osmolarity, oxygen tension, bile, $Mg^{2+}$ concentration, and short chain fatty acids. This review will discuss the current understanding of invasion control, with emphasis on the interaction of environmental factors with genetic regulators that leads to productive infection.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 1996.12a
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• pp.69-69
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• 1996

• Journal of Korean Academy of Fundamentals of Nursing
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• v.23 no.2
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• pp.149-160
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• 2016

Purpose: The purpose of this study was to identify factors influencing performance of MultiDrug-Resistant Organisms (MDROs) infection control by nurses in general hospitals. Methods: The research design was a descriptive survey design using convenience sampling. Data were collected from 130 nurses working in 6 general hospitals. Collected data were analyzed using SPSS/WIN 21.0 program for descriptive statistics, t-test, ANOVA, Pearson correlation coefficients and multiple regression analysis. Results: General hospital nurses' MDROs infection control performance was influenced by their awareness of environmental safety, recognition of MDROs infection control, number of beds in the hospital, whether nurses had nursing experience with infection control and guidelines for MDROs infection control. The most important predictors of MDROs infection control performance were awareness of environmental safety and recognition of MDROs infection control. Conclusion: Findings indicate that it is necessary to include content related to awareness of environmental safety and recognition of infection control in developing MDROs infection control education programs for general hospital nurses.