• Journal of Wetlands Research
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• v.13 no.2
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• pp.231-242
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• 2011

Recently, the green spaces in the urban areas were greatly reduced due to urbanization and industrialization. As urban structures such as roads and buildings are built, the amount of impervious area within a watershed increases. High impervious surfaces are the common causes of high runoff volumes as the soil infiltration capacity decreases and the volume and rate of runoff increase thereby decreasing the groundwater recharge. These effects are causing many environmental problems, such as floods and droughts, climate change, heat island phenomenon, drying streams, etc. Most cities attempted to reduce sewer overflows by separating combined sewers, expanding treatment capacity or storage within the sewer system, or by replacing broken or decaying pipes. However, these practices can be enormously expensive than combined sewer overflows. Therefore, in order to improve these practices, alternative methods should be undertaken. A new approach termed as "Low Impact Development (LID)" technology is currently applied in developed countries around the world. The purpose of this study was to effectively manage runoff by adopting the LID techniques. Small Constructed Wetland(Horizontal Subsurface Flow, HSSF) Pilot-scale reactors were made in which monitoring and experiments were performed to investigate the efficiency of the system in removing pollutants from runoff. Based on the results of the Pilot-plant experiments, TSS, $COD_{Cr}$, TN, TP, Total Pb removal efficiency were 95, 82, 35, 91 and 57%, respectively. Most of the pollutants were reduced after passing the settling tank and the vertical filter media. The results of this study can contribute to the conservation of aquatic ecosystems and restoration of natural water cycle in the urban areas.

• Development and Reproduction
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• v.13 no.3
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• pp.163-172
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• 2009

Some organotin compounds such as butyltins and phenyltins are known to induce impo-sex in various marine animals and are considered to be endocrine disruptors. In this study, the effect of organotins on follicular steroidogenesis in amphibians was examined using ovarian follicles of Rana dybowskii and Rana catesbeiana. Isolated follicles were cultured for 6 or 18 h in the presence and absence of frog pituitary homogenate (FPH) or various steroid precursors, and the levels of product steroids in the culture media oassay. Among the butyltin compounds, tributyltin (TBT) strongly and dose-dependently inhibited the FPH-induced synthesis of pregnenolone ($P_5$) and progesterone ($P_4$) by the follicles. TBT also strongly suppressed the conversion of cholesterol to $P_5$ and partially suppressed the conversion of $P_5$ to $P_4$. A high concentration of dibutyltin (DBT) also inhibited steroidogenesis by the follicles while monobutyltin and tetrabutyltin had negligible effects. The toxic effect of TBT or DBT was irreversible and a short time of exposure (30 min) was enough to suppress steroidogenesis. All the phenyltin compounds significantly inhibited FPH-induced $P_5$ synthesis by the follicles. The effective dose of 50% inhibition by diphenyltin was $0.04\;{\mu}M$ and those of monophenyltin and triphenyltin were $0.24\;{\mu}M$ and $0.3\;{\mu}M$, respectively. However, none of the phenyltin compounds significantly suppressed the conversion of $P_4$ to $17{\alpha}$-hydroxyprogesterone ($17{\alpha}$-OHP) (by $17{\alpha}$-hydroxylase), $17{\alpha}$-OHP to androstenedione (AD) (by $C_{17-20}$ lyase), or AD to testosterone by the follicles. Taken together, the data show that among the steroidogenic enzymes, P450scc in the follicles is the most sensitive to organotin compounds and that an amphibian follicle culture system can be a useful screening model for endocrine disruptors.

• Journal of Sensor Science and Technology
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• v.11 no.2
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• pp.102-110
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• 2002

The chemical and mechanical characteristics of a new surface modifier, dichlorodimethysilane (DDMS, $(CH_3)_3SiCl_2$), for stiction-free polysilicon surfaces are reported. The main strategy is to replace the conventional monoalkyltrichlorosilane(MTS, $RSiCl_3$) such as octadecyltrichlorosilane (ODTS) or 1H,1H,2H,2H-perfluorodecyltrichlorosilane (FDTS) with dialkyldichlorosilane (DDS, $R_2SiCl_2$) with twit short chains, especially DDMS. DDMS, with shorter chains in aprotic media, rapidly deposits on the chemically oxidized polysilicon surface at room temperature and successfully prevents long cantilevers of 3 mm in length from in-use as well as release stiction. DDMS-modified polysilicon surfaces exhibit satisfactory hydrophobicity, long term stability and thermal stability, which are comparable to those of FDTS. DDMS as an alternative to FDTS and ODTS provides a few valuable advantages; ease in handling and long-term storage in solution, low temperature-dependence and low cost. In addition to the new modifier molecule, the simplified process of direct release right after washing the modified surface with isooctane was proposed to cut the processing time.

• Korean Journal of Ecology and Environment
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• v.39 no.4 s.118
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• pp.489-497
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• 2006

The feasibility of the Natural and Ecological Wastewater treatment System (NEWS) was examined for rural wastewater treatment in Korea. The intermittent trickling biofilter with high hydrophilic filter media was used for pretreatment for suspended solids and organic pollutants. The subsequent constructed wetland with porous granule materials was used for promoting nutrient removal. The results show that the removal efficiencies of the system were high with respect to the water quality parameters except COD. Even if the effluent from the biofilter did not meet the guidelines for wastewater treatment plant effluent in Korea in terms of $BOD_5$ and TN, the final effluent of the system meets the guidelines us to good performance of the constructed wetland. The regression analysis between pollutant loading rate and removal rate indicated that the system could have stable removal for SS, $BOD_5$, TN, and TP in the given influent ranges. The analysis in the winter period indicated that the wetland covered with transparent polycarbonate glass had the statble performance during the winter period dus to increase of temperature inside the wetland without any heating system. With the stable performance, effective poilutant removal, low maintenance, and cost-effectiveness, the NEWS could be considered as an alternative treatment system for decentralized regions and rural communities in Korea.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.3
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• pp.11-19
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• 2009

At present, an intelligent transport system (ITS) is being actively introduced as an alternative plan to solve various transport problems, and a traffic information provision service, a field of ITS, is being provided to users through diverse media. However, the evaluation of how useful the traffic information provided to the road users is limited to a simple questionnaire, and the systematic evaluation about what factors affect the usefulness of traffic information has not been realized. Therefore, it is impossible to calculate user convenience occurring due to traffic information, This paper aimed to develop an index to evaluate user satisfaction levels with traffic information and develop a user satisfaction level model. A result of establishing a user satisfaction level model by executing a questionnaire survey for the analysis object of variable message sign (VMS), a representative information provision medium, showed that 'desire satisfaction', 'trust', 'understanding', and 'efficiency' have an effect. Of them, the 'understanding' showed the highest level, so it was seen that, in case of VMS, how easily the character, figure, expression, etc. provided in the information was understood by users has the biggest effect on the satisfaction level of the information. The next levels of effects on the satisfaction was in the order of 'user trust', 'efficiency', and 'desire satisfaction'.

• Informatization Policy
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• v.21 no.2
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• pp.89-110
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• 2014

As a travel demand management and environmental policy, the government actively promotes alternative work arrangements such as telecommuting. Against this backdrop, several empirical studies, which aim to verify the benefits of telecommuting, have been recently conducted. Little consensus, however, exists with respect to the defining, measuring, and forecasting telecommuting, although these are fundamental basis of policy evaluation and academic research. As a fundamental research for analyzing telecommuting impacts, this paper reviews various definitions regarding telecommuting, examines telecommuting penetration and level of telecommuting through review of available survey data in Korea, and forecasts future penetration. The result suggests that current home-based telecommuting penetration and level of telecommuting is approximately 0.5 to 1.1% and 0.2 to 0.5%, respectively, and is approximately 0.2% and 0.1%, respectively, for the center-based telecommuting. In addition, shift-share analysis shows that home-based telecommuting penetration in the Seoul Metropolitan Area in 2020 will be 1.3%, not much different with the current value. Consequently, current telecommuting penetration is much lower than the value that is fed to us by the media (10~20%), and the future prospect is also much lower than the goal of government (30~45%); thus, we can conclude that government's goal of telecommuting promotion is difficult to meet if active encouragement policy will not be introduced.

• Journal of Soil and Groundwater Environment
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• v.9 no.3
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• pp.49-55
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• 2004

A soil enrichment LYF-1 culture from a contaminated site, which could reductively dechlorinate 900 $\mu$M (ca. 150 mg/L) of tetrachloroethylene (PCE) stoichimetrically into cis-1,2-dichloroethylene (cis-DCE), was established and characterized. The enrichment culture can use yeast extract, peptone, formate, acetate, lactate, pyruvate, citrate, succinate, glucose, sucrose, and ethanol as electron donors for dechlorination of PCE. Addition of NO$_2$$^{[-10]}$ and NO$_3$$^{[-10]}$ as alternative electron acceptors showed complete inhibition of PCE dechlorination, but S$_2$O$_3$$^{-2}$ , SO$_3$$^{-2}$ and SO$_4$$^{-2}$ had no significant effect on PCE dechlorination. The enrichment culture was attached to ceramic media in an anaerobic fixed-bed reactor. The fixed-bed reactor showed more than 99％ of PCE degradation in the range of PCE loading rate of 0.13-0.78 $\mu$moles/L/hr. The major end product of PCE dechlorination was cis-DCE.

• Korean Journal of Acupuncture
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• v.37 no.3
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• pp.172-182
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• 2020

Objectives : In this study, we conducted a focus group interview among expatriates living in Korea, to investigate their experiences and perceptions of acupuncture and Korean Medicine in order to improve the usage of Korean Medicine in the medical tourism market. Methods : The inclusion criteria for the focus group interview was: (1) participants between the age of 20 to 75 years old; (2) those who had lived in Korea for more than 90 days, and (3) those who were able to express their thoughts freely in English. The participants were informed that the interviews will be recorded and transcribed. We ended recruitment once saturation of materials was met. Semi-structured interviews were conducted, and the data was analyzed after each interview. Results : The interviews were held between June to December 2016. Twenty-four participants were recruited but four dropped out and a total of twenty participants successfully finished the interviews. Six focus group interviews were conducted. Analysis revealed that Korean Medicine was relatively less known compared to Traditional Chinese Medicine or Complementary and Alternative Medicine. Participants automatically associated acupuncture with the management of pain or stress and replied that these were the areas that they thought acupuncture would be most effective. Positive experiences with acupuncture and with the acupuncture practitioners were factors that promoted the use of acupuncture whereas lack of awareness, accessibility and accreditation were factors that hindered its use. Other factors that hindered the use of acupuncture was needle phobia and the perception that acupuncture lacks scientific evidence. Conclusions : Awareness on Korean Medicine and acupuncture is low. Participants lack awareness on what diseases acupuncture can treat, the scientific evidence behind the mechanism of action, and the rigorous education system that Korean Medicine doctors must go through to get their license. Rigorous marketing should be encouraged, which includes greater exposure in the media, more honest reviews from patients, and promotion of the scientific evidence base.

• Journal of Korean Philosophical Society
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• v.123
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• pp.87-110
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• 2012

The kitsch was emerged from the people's cultural desire in the conditions of the various duplicating technology, the capital economy system, and the civil revolution in the western modern mass society. But it is underestimated constantly because of the conspicious consumption and the aesthetic inadequacy. Even though some kitsches are elevated to the 'kitsch arts' in the historical description of the modern arts, still the most of kitsches are remained as 'just kitsches' and excluded from the aesthetic research according to the double standard. In this essay, I research for whether anti-kitsch theory is convincing theoretically and practically. Anti-kitsch theory criticizes the kitsch on the basis of the modernist aesthetics, in which the 'fine art' provokes the aesthetic pleasure in the disinterested contemplation. But kitsch purposes for the sensual gratification and the sentimentality. So the anti-kitish theorists conclude that the kitsch is the bad taste. In critically analyzing the argumentation of Greenberg's. Kaplan's and $C{\tilde{a}}linescu^{\prime}s$, I refute the privileged prejudice of the ideal critic. They don't justify the criteria of the classification of 'art'/ 'kitsch'. They supplement the economical and the political grounds for the evaluative theory of the kitsch. But the argumentation of the kitsch is consumed conspicuously and results in the unlettered masses is not sufficient. People produce and enjoy the kitsches in the various ways. People envelope the genres, styles and media of the kitsches and they try to suggest the new horizon of the popular aesthetics. So anti-kitsch theories cannot be accepted because they adhere to the elitism and formalism. The exclusion of the kitsch is the derogation for people's taste. Also they didn't reflect the contemporary cultural practice and the aesthetic needs in the system of post-art. The alternative aesthetics of the kitsch is the topic of my next essay.

• Journal of Legislation Research
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• no.44
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• pp.63-101
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• 2013

This article firstly explores into the concepts, components, and pictures of institutional realization of competition and diversity respectively on the premise that competition and diversity comprise the primary objectives to be pursued by the broadcasting-related laws which provide the concrete measures of media policy, and argues that while the competition objective has differentiation factors, there are also particularities in the diversity value in the broadcasting-related laws as sector-specific competition laws. Then assuming that special competition rules including structural regulatory measures particularly in the broadcasting market are required in order to realize values of competition and diversity harmoniously, this article suggests the following improvement directions for regulations aimed at protection of competition and diversity in the broadcasting-related laws. The first one is with the improvement method for regulations aimed at protection of competition. Regulation on share of audience as an ex ante regulation of status and regulation on prohibited activities as an ex post regulation of conduct may play important roles in substituting the causative regulation while seeking for diversity value. For this purpose, it is needed to develop a concrete method that incorporates diversity-related factors as consideration factors in the standard for determining illegality of prohibited activities by inference to methods of determining illegality in the competition law. The second one is with the improvement method for regulations aimed at protection of diversity. This could be considered from three viewpoints that are the setting of regulatory objectives, the identification of alternative regulatory measures, and the choice of regulatory measures and levels suitable for regulatory objectives. From these viewpoints, the regulatory framework should be improved mainly with institutional measures in which diversity value is used for tools of assessment and analysis, not just remaining as mere rhetorical devices, and whether or to what extent to maintain regulations seemingly unreasonable in terms of harmonization with economic objectives such as competition should be discreetly reviewed.