• Korean Journal of Biological Psychiatry
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• v.24 no.2
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• pp.59-67
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• 2017

Shift workers experience a disruption in the circadian sleep-wake rhythm, which brings upon adverse health effects such as fatigue, insomnia and decreased sleep quality. Moreover, shift work has deleterious effects on both work productivity and safety. In this review, we present a brief overview of the current literature on the consequences of shift work, especially focusing on attention-associated cognitive decline and related behavioral changes. We searched two electronic databases, PubMed and RISS, using key search terms related to cognitive domains, deleterious effects, and shift work. Twenty studies were eligible for the final review. The consequences of shift work can be classified into the following three categories extracted from the literature review : 1) work accidents ; 2) commuting accidents such as car accidents that occur on the way to and from work ; and 3) attendance management at work (i.e., absenteeism, tardiness, and unscheduled early departure). These cognitive and behavioral consequences of shift work were also found to be associated with sleep disorders in shift workers. Thus, improvements in the shift work system are necessary in order to enhance workers' health conditions, work productivity, and safety.

• Korean Journal of Ecology and Environment
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• v.34 no.3 s.95
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• pp.206-214
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• 2001

Water quality and Pollution state of Lake Chungcho were evaluated during three years from 1998 to 2000. We surveyed physicochemical parameters, and TSI (trophic state index) was calculated using TP, Chl. a, and SD (secchi disc transparency) data of growing season average. Water samples were collected bimonthly except freezing season. During the study period, total annual precipitation in 1998, 1999 and 2000 year was 1,797,1,722 and 1,345 mm, respectively. Salinity and conductivity were high($29.3{\pm}5.5\;ppt$, and $45,105{\pm}7,585\;{\mu}S/cm$) then other lagoons in the Eastern Coast of Korea. Chemocline was formed by salinity at $0.5{\sim}1.5\;m$ water depth. As a result of this, DO concentration of hypolimnion was below $3.0\;mgO_2/L$. Especially, when intense chemocline was formed, temperature of hypolimnion was higher than epilimnion. Secchi disc transparency, chlorophyll a, and COD were $1.8{\pm}0.3\;m$, $15.7{\pm}20.7\;mg/m^3$, and $3.1{\pm}0.8\;mgO_2/L$, respectively. Most of TN/TP ratios below 20, but concentration of TN and TP was high. Values of TSI ranged between 59 and 77, indicating a eutrophic condition in this system.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.6
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• pp.727-735
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• 2007

The use of water by cities is increasing owing to industrialization, the concentration of population, and the enhancement of the standard of living. Accordingly, the amount of waste water is also increasing, and the degree of pollution of the water system is rising. In order to solve this problem, it is necessary to remove organisms and suspended particles as well as the products of eutrophication such as nitrates and phosphates. This study developed a high-end treatment engineering solution with maximum efficiency and lower costs by researching and developing a advanced treatment engineering solution with the use of Biosorption. As a result, the study conducted a test with a $50m^3/day$ Pilot Scale Plant by developing treatment engineering so that only the secondary treatment satisfies the standard of water quality and which provided optimal treatment efficiency along with convenient maintenance and management. The removal of organisms, which has to be pursued first for realizing nitrification during the test period, was made in such a way that there would be no oxidation by microorganisms in the reactor while preparing oxygen as an inhibitor for the growth of microorganism in the course of moving toward the primary settling pond. The study introduced microorganisms in the endogeneous respiration stage to perform adhesion, absorption, and filtering by bringing them into contact with the inflowing water with the use of a sludge returning from the secondary settling pond. Also a test was conducted to determine how effective the microorganisms are as an inner source of carbon. The HRT(Hydraulic Retention Time) in the nitrification tank (aerobic tank) could be reduced to two hours or below, and the stable treatment efficiency of the process using the organisms absorbed in the NAR reactor as a source of carbon could be proven. Also, given that the anaerobic condition of the pre-treatment tank becomes basic in the area of phosphate discharge, it was found that there was excellent efficiency for the removal of phosphate when the pre-treatment tank induced the discharge of phosphate and the polishing reactor induced the uptake of phosphate. The removal efficiency was shown to be about 94.4% for $BOD_5$. 90.7% for $COD_{Cr}$ 84.3% for $COD_{Mn}$, 96.0% for SS, 77.3% for TN, and 96.0% for TP.

• Journal of Korean society of Dental Hygiene
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• v.9 no.3
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• pp.415-425
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• 2009

Objectives : In this study, the dental treatment satisfaction degree of the patients, who experienced the sleep dental treatment or non-sleep dental treatment, the revisit rate and the differences among the encouraging intention were compared and analyzed, and the primary factors through which the satisfaction degree of sleep dental treatment has influence on the revisits and the encouraging intention were analyzed, and the proposal was made on clinic management to raise qualitative medical service level on the basis of this study. Methods : The questionnaires filled out by the 202 users of a certain dental clinic located in Pohang-si, Gyeongbuk were analyzed. The frequency analysis and the crosstabulation analysis of the general characteristics of survey participants were carried out, and the satisfaction difference between the sleep dental treatment and the non-sleep dental treatment was identified with the t-test analysis. The multiple regression analysis were carried out to identify the factors through which the sleep dental treatment has influence on the through which the satisfaction degree of sleep dental treatment has influence on the satisfaction degree of the medical service and the revisited dentists. Results : In the medical service satisfaction degree in general, the sleep dental treatment had the higher meaningful value than the non-sleep dental treatment(p<0.05). In the case of the difference in satisfaction degree on each medical service factor, the satisfaction of the sleep treatment group was high in every case, but the meaningful difference showed up in the factors of waiting time, treatment procedure, revisit and the encouraging intention(p<0.01). The revisit to the sleep treatment dental clinic and the recommending dentist increased in proportion to the satisfaction degree of sleep dental treatment, and the Beta value appeared to be 0.337 at the influence of the subordinate variable(p<0.001). As for the influence on the sleep dental treatment satisfaction, the Beta value of the dental hygienist was the highest, marking the value at 0.375(p<0.01). As for the satisfaction of the patients who experienced the sleep dental treatment, the Beta value of the treatment fee was the highest, marking 0.352(p<0.001), in the multiple regression analysis of the revisit and the encouraging intention, and the 0.156 of dentist factor and the 0.152 of treatment procedure and waiting time showed lower regression coefficient(p<0.05). Conclusions : It is assumed that the satisfaction degree of sleep dental treatment, which is carried out as a new dental service has influence on the increase of revisit to the dental clinic as an important factor. But it was disclosed that the high level of treatment fee has the biggest influence on choice of revisit to the dental clinic. In the current medical charge system, the sleep dental treatment appeared to have a big influence on raising the quality of dentists, the satisfaction of patients, the revisit and encouraging intention, and also the roles of the dental hygienist was important. It is assumed that these facts are functioning as the factors that are linked to the increase of revisit and the encouraging intention.

• Korean Security Journal
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• no.20
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• pp.119-140
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• 2009

It seems that security police's business to secure safety of state and citizens has existed since the mankind began to create a community. State was not fully responsible for such security business from the beginning. The business was carried out autonomously by the private sector for a long period. However, as the state system had been strengthened, the public sector absorbed the function. But in the modern society where various risks exist, safety of society could not be guaranteed only by public police. Accordingly, cooperation with the private sector is indispensable. In the limit of public police, autonomous organization of security companies and general citizens is expanding its scope. As a result, they should exercise partnership as a tripod to build social safety net. Security police failed to secure manpower exclusively responsible for security, despite various businesses and excessive mobilization. Accordingly, their professionalism and ability to cope with crisis are being questioned. In particular, efficiency of security police is becoming a more urgent issue in an era of international terrorism. Private sector can be classified into security companies and private autonomous organization. In case of security companies, the problem is quality and business ability of guards compared to a rapid external growth such as quantitative expansion and advancement into various businesses. In terms of pure private activity, the necessity of understanding of public police activity and conditions for organizational and continuous activity should be prepared. To tide over such problems and effectively achieve the common goal, changes in the method of employment, new establishment of security police department, and strengthening of professionalism and crisis management ability are necessary in the public police sector. In case of security companies, improvement of relations with public police through joint education, strengthening of business ability and activation of business cooperation through these matters are necessary. To maximize activity of pure private sector, it needs to establish reserve police, manage such private autonomous organization and bolster publicity with citizens.

• Korean Journal of Ecology and Environment
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• v.50 no.3
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• pp.337-354
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• 2017

Cyanobacteria Aphanizomenon population is widely distributed in the world, and well known as harmful algae by producing toxins and off-flavor materials, thus belonging to one of the taxa that became more interested in the field of limnoecology. In this study, the frequency, intensity, and duration of Aphanizomenon occurrence were increased with the abnormal drawdown of water level in the winter in Boryeong Reservoir, and the spatial and temporal characteristics of them are compared with each other in the perspective of hydrometeorology (1998 to 2017) and limnology (2010 to 2017). In Korea, Aphanizomenon flourished mainly in high temperature, and the appearance in the low temperature was rare in total five times. The harmful cyanobacteria Aphanizomenon was observed in the low temperature (December to February) in Boryeong Reservoir from 2014, and then reached a maximum value of $2,160cells\;mL^{-1}$ in January 2017. In addition, the period exceeding $1,000cells\;mL^{-1}$ at this time was more than 3 months. This was simultaneously associated with abnormal water level fluctuation in the low temperature ($<10^{\circ}C$). The large drawdown of water level in the winter season has the potential to promote or amplify the germination and development of harmful algae. Also, subsequent water quality and ecological impacts(e.g., algal toxins and off-flavor substances) need to be considered carefully.

• Journal of the korean academy of Pediatric Dentistry
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• v.42 no.2
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• pp.158-163
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• 2015

General anesthesia (GA) for dental care in handicapped patients is necessary to facilitate the provision of safe, efficient, and effective quality treatment. The aims of this study were to determine the anesthetic characteristics of handicapped patients in need of dental treatment in these day care units, and to establish for plan to provide better services. 325 patients who had outpatient general anesthesia from January 2005 to March 2014 were assessed for this study. Patients' distribution and treatment patterns were examined. The proportion of male patients (202, 62.2%) was higher than female patients (123, 37.8%) and the largest group of patients were 5 to 10 years old (85, 26.2%). The reasons for general anesthesia included mental and physical disabilities (207, 63.7%), behavior management (84, 25.8%), parent needs (14, 4.3%), and so on. Restorative treatment was the most common procedure with the average of 4.2 teeth treated per one patient and 43 (13.2%) patients underwent general anesthesia for dental treatment more than once. To expand and improve access to the dental care of the disabled, improvement of the health care system, enhancement of their training for dental care by professionals, and enlarging caregivers'understanding of the importance of oral care in the early stages are required.

• Korean Journal of Environment and Ecology
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• v.17 no.3
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• pp.258-267
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• 2003

The purpose of this study is to present improvement devices of urban center's green function in the Public Open Space Attached Building(P.O.S.) in Incheon, Korea. Study sites were the P.O.S. of office building(10 place), transportation facility building(3 places), government office building(2 places) that were made up 1994∼2002 and analyzed establishment, using and planting status. And P.O.S.'s planting area structure of Osaka and Kawasaki in Japan that is operating P.O.S. system similar to Korea was compared with study sites of Incheon. P.O.S. of Incheon is not managing as valuable urban center's green and establishing to satisfy legal requirement. The strengthening devices of P.O.S. function are as follows. First, it is desirable that planting area rate of P.O.S. in order to develop small park in urban center is increasing by 40% that is children's park level. Second, it must be conferred about planting basis, tree selection and planting method etc. of P.O.S. with green and park development department at building authorization. Third, by the 'landscape planting standard of plottage' that is becoming planting standard of P.O.S is heightened and must increase quality and amount of green. Fourth, it is required mandatory establishing of sign so that citizens can search easily and utilize of P.O.S. Fifth, legal regulation should be decided to prevent that P.O.S. is used unlike purpose originally.

• Journal of The Korean Association For Science Education
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• v.37 no.5
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• pp.775-785
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• 2017

The purpose of this study is to analyze the outcome of 'The second plan for identifying and nurturing of science-gifted student' and investigate the implications for the third plan. 'The second plan for identifying and nurturing of science-gifted student' was made for the promotion of science-gifted education from 2013 to 2017. This plan is composed of three strategies with 25 sub-projects: a systematic identification of science-gifted students with potential, an activation of creative and integrated science-gifted education and an establishment of optimized science education supporting system. We supposed six implications through the investigation of the performance analysis of each sub-project. First, the third plan should be composed of projects to be able to be supported directly. Second, the paradigm shift is needed from quantitative expansion to qualitative expansion. Third, third plan should include a special support for profoundly gifted students. Fourth, a specialization plan for science-gifted institute is required. Fifth, it is necessary to establish a camp or residential type gifted institute. Sixth, it is needed to have a quality management of science-gifted programs and MOOC (massive open online course) on science-gifted programs are needed.

• Journal of the Korean association of regional geographers
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• v.15 no.6
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• pp.720-735
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• 2009

This paper studies the characteristics of the restructuring of chemical industrial complex in JiLin city since 1978 focusing on enterprise organization, the process of production, labor, and consumer market. The number of chemical industrial enterprises and their partnership with subcontractors have increased since 2001. As for the type of cooperation group, research institutes and local government are accounted for the greatest portion. The chemical industrial enterprise in JiLin which has adopted Fordism production method still has the highest percentage in 2007. And in the shift process of production system after China's entry into WTO(in 2001), chemical industrial enterprise in JiLin city takes allowing more investment in production technologies as core strategy, while taking improvement in equipment and development of new products as core strategy in the shift process of production technology. The degree of labor re-education was highest in 2007, and as for the relationship between labor and management, enterprises which evaluate the ability of performance of duty are increasing. The characteristics of restructuring of chemical industrial complex on consumer market, domestic market accounted for the greatest portion, on the other side the export is feeble. As for strategy of market restructuring, industrial enterprise in JiLin city should use Quality improvement and high-value added as core strategies to cope with alteration of market.