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Potential Welfare Loss from Using Imperfect Environmental Taxes (불완전한 환경세 사용에 따른 잠재적 후생 손실)

  • Hong, Inkee
    • Environmental and Resource Economics Review
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    • v.24 no.1
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    • pp.1-53
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    • 2015
  • In environmental policy areas, a greater use of economic instruments (EIs) has recently been observed in many countries. However, EIs are heterogeneous policy tools. The textbook case of a Pigouvian tax is far from widely used, mainly due to the information requirements and other structural and institutional constraints. The successful implementation of EIs might heavily depend on pre-existing structural and institutional conditions. Moreover, these institutional conditions are particularly unfavorable in developing countries. Using a simple analytical general equilibrium model, this paper examines how these constraints affect the welfare gain from the introduction of environmental taxes in developing countries. First, this paper solves for the second-best optimal Pigouvian tax and output tax in the presence of a distortionary tax on market use of labor. The result confirms that an environmental output tax achieves a socially-efficient level of emissions in the least-cost manner only if the nature of the linkage between the tax base and the environmental damage is fixed. Second, incorporating structural and institutional constraints into the model through a set of parameter values from China and the US, this paper calculates the net welfare effects of either using the ideal Pigouvian tax or instead using an output tax. The numerical simulation results show that the net welfare gain from the use of an ideal Pigouvian tax could be more than six times larger than that of an output tax in developing countries. On the other hand, the welfare gain is only 50 percent in developed countries. This means that the potential welfare disadvantage from using output taxes instead emissions tax for environmental purposes could be much greater in the case of developing countries.

The Economic Impact of Contaminated and Noxious Sites : A Meta Analysis (오염-유해시설의 경제적 영향 : 메타분석)

  • Won, Doo Hwan
    • Environmental and Resource Economics Review
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    • v.17 no.1
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    • pp.165-196
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    • 2008
  • This paper reports a quantitative meta analysis of the economic impacts of localized noxious and contaminated sites. Using either hedonic property value or stated preference methods, economists have studied the effects of contamination or noxious activities, or the benefits realized from their elimination, on real estate prices at more than 40 sites. In support of wise public and private investments in environmental quality, most of these studies aim to inform decision makers about the benefits of remediation and cleanup. Their results vary considerably, but there has been no previous systematic effort to analyze the differences and identify shared insights. This study uses established methods of meta analysis to identify points of agreement and differences in this body of literature. The studies are characterized by the type of site, modeling approach, geographic extent of impacts, data features, and other key factors that underlie their value estimates. The impact estimates are normalized as proportional effects on property values. This study attempts to discover whether the estimated economic impacts of contamination or noxious activity differ according to these characteristics of the studies, and whether anything general can be said about the economic consequences of site contamination and remediation. Bivariate, multivariate, and logit techniques are applied to the data. The results suggest that the property value is the most sensitive to water base contamination, published case studies result in systematically greater environmental value than those in unpublished reports, and real estate markets show responses to environmental condition changes.

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Effect of Sleep Duration on Dietary Habits and Body Composition of University Students (대학생의 수면시간에 따른 식습관 및 체조성에 관한 연구)

  • Kim, KyungHee;Cho, HeeSook
    • Journal of the Korean Society of Food Culture
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    • v.28 no.5
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    • pp.539-546
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    • 2013
  • The aim of this study was to investigate the effect of sleep duration on dietary habits and body composition of university students. Sleep duration has recently been added to the list of risk factors for obesity. However, studies on this topic are fairly limited particularly in Korea. We studied the relationship between the duration of sleep and obesity principally based on body mass index and %body fat in university students. For this purpose, a survey was conducted on a total of 312 university students. The subjects enrolled for this study were divided into two groups: (1) those with sleep duration of <7 hours (148 students) and (2) those with sleep duration of >7 hours (164 students). Based on a self-reporting method, the participants filled up the questionnaires for more than 20 minutes. Based on the overall data obtained, we observed that most students (52.88%) skipped breakfast. This was mainly due to shortage of time (60.58%). We also observed that self-reporting dietary preferences included eating irregular meals (49.04%), overeating (19.55%), imbalanced diet (16.35%), and skipping meals (9.94%). It was found that cookies were the favorite snacks in the majority of the participants (50%). Our data reveal that the body mass index, fat mass, visceral fat, and subcutaneous fat, respectively of the shorter sleep duration group (<7 h/day) were 23.78 $kg/m^2$, 19.13 kg, 2.23 kg, and 11.15 kg. In contrast, in those of the control group (7 h/day), these values were found to be 21.84 $kg/m^2$, 13.88 kg, 1.56 kg, and 12.11 kg. We also observed that there were significant correlations of sleep duration with body mass index (p<0.05), fat mass (p<0.01), visceral fat (p<0.01), and beck depression score (p<0.01). Our data suggest that the body mass index in the shorter sleep duration group was higher than that of the control group; however, %fat, visceral fat, and subcutaneous fat in the shorter sleep duration group were found to be higher than those of the control group. The data obtained through our study suggest that short sleep duration is clearly associated with a modest increase in general and abdominal obesity particularly in university students.

A Fundamental Study for the Automatic Control System in Greenhouse Using Microcomputer(III) -A variation of temperature and humidity by the window opening ways of the even-Span type house- (마이크로컴퓨터에 의한 시설재배의 자동화에 관한 기초연구(III) -양지붕형 하우스의 창 개방방법에 따른 온.습도의 변화-)

  • 김진현;김철수;구건효;이기명
    • Journal of Biosystems Engineering
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    • v.20 no.2
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    • pp.162-172
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    • 1995
  • The ventilation in greenhouse have been important for such as adjustment of temperature, supplying of the oxygen, prevention of the overhumidity, density adjustment of $CO_2$, discharge of harmfulness gas, etc. However, the general ventilation which had been used the quantitative control method in discharge of a property of air mechanism in greenhouse, and caused mainly in waste of the heating energy and growth obstacle of the vegetable. Therefore, this study was peformed to obtain more scientific ventilation method using by analysis and measurement of the isothermal lines according to opening of window ventilation in greenhouse, and the results are summarized as follows. 1. The ventilating amount was more influenced by rather opening amount of window than the ventilating time. 2. In window ventilation, the temperature in greenhouse was mostly changed within 5 minutes after ventilating not regard to the spot of opening, after about 10 minutes temperature became to equilibrium state under the respective ventilating conditions. 3. In opening of the skylight only, isothermal lines were complicated, therefore, a tall vegetable may be possible to damage by a cold-weather from the lower central port in greenhouse. 4. Isothermal lines were a tendency to simply in opening of a side window that may be more effective ventilation in kinds of the short vegetable. 5. In conditions of internal temperature>setting temperature>external temperature, a skylight can be suitable to open 10~20cm in order to the optimum ventilation in greenhouse. 6. In conditions of internal temperature>external temperature>setting temperature, opening of all the windows or both the side windows that can be suitable in order to obtain the optimum ventilation in greenhouse. 7. An effect of ventilation was the most excellent to open of all the windows or both the side windows, and it were also found orderly excellent to open of the side window and the skylight or the skylight only, to open of the side window only. 8. Temperature was varied as the equation of T=Tc+ (To-Tc)e-at, and the ranges of (a) values were limited within 0.34~0.68. 9. A variations of humidity were similar to that of temperature, s.

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Effects of the Kind and Concentration of Salt on Oxidation of Lipids and on Formation of Flavor Components in Fermented Anchovies (멸치젓에 사용한 염의 종류와 농도가 지질의 산화와 맛성분에 미치는 영향)

  • 장백경;이혜수
    • Korean journal of food and cookery science
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    • v.2 no.1
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    • pp.38-44
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    • 1986
  • Effects of the kind and concentration of salt on oxidation of lipids and on formation of flavor components have been studied with four varieties of fermented anchovies prepared with 20% sun-dried salt(sample B) , 12% refined salt (sample C), 16.5% refined salt (sample D) and 16. 5% refined salt Plus 25% brine (sample E). The sample B showed higher peroxide and TBA value and also higher content of TMA thar. those prepared with refined salt. The amounts of amino-N and VBN in sample B appeared larger than in sample D but was in a similar level with those in sample C. On the other hands, much smaller amounts of lactic and succinic acid were observed in sample B compared with in sample C and D. Sample C revealed the highest level of lactic acid among the samples tested. The changes in the amounts of each free amino acid displayed similar tendencies in all samples, except decreasing tendency of tyrosine in sample B and increasing tendency of aspartic acid in sample C. Also observed was lower IMP and inosine level in sample B than in C and D, but hypox-anthine level was higher in B. In general, sample I indicated remarkably lower values of experimental data in all cases mentioned above, but the highest TBA balue.

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A Time Variable Modeling Study of Vertical Temperature Profiles in the Okjung Lake (옥정호의 연직 수온분포에 관한 시변화 모델 연구)

  • Park, Ok-Ran;Park, Seok-Soon
    • Korean Journal of Ecology and Environment
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    • v.35 no.2 s.98
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    • pp.79-91
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    • 2002
  • A time variable modeling study was performed for seasonal variations of vertical temperature profiles in the Okjung Lake located in upstream of the Sumjin River. Based on the model structure of the US Army Corps of Engineer's CE-QUAL-W2, the lake was divided into 3 branches, 50 longitudinal segments and 49 vertical layers and vertical profiles of water temperature and current velocity were simulated over one year. The model results were calibrated and verified against vertical profiles of water temperature measured every month from March 1998 to February 1999 at 5 different locations. The model results showed a good agreement with the field measurements. The hydrologic balance during this period was validated by comparing the simulated values of surface elevation level with the measured data. There was some discrepancy in July data between the model results and the fleld measurements. This could be attributed partially to the inadequacy of the model to the highly hydrodynamic nature of water body and partially to the lack of accuracy in local atmospheric temperature data during summer monsoon period. The model results have shown that there was no seasonal over-turn in most part of the Okjung Lake, where water temperature maintained above $4^{\circ}C$ over one year. In the upstream shal-low area (depth<20 meter), however, temperature at surface layer fell below $4^{\circ}C$ and water was frozen such that slight over-turn would occur during winter period. From this study, we concluded that the Okjung Lake is oligomictic. This conclusionis significantly different from the general pattern that the lakes located from $20^{\circ}C$ to $40^{\circ}C$ latitude would be warm monomictic. From the examination of simulated current velocity distribution, it was found that the upstream inflows would infiltrate into mesolimnion of the lake during hydrodynamic summer monsoon periods due to the thermal density of water.

A Study on the Identification and Classification of Relation Between Biotechnology Terms Using Semantic Parse Tree Kernel (시맨틱 구문 트리 커널을 이용한 생명공학 분야 전문용어간 관계 식별 및 분류 연구)

  • Choi, Sung-Pil;Jeong, Chang-Hoo;Chun, Hong-Woo;Cho, Hyun-Yang
    • Journal of the Korean Society for Library and Information Science
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    • v.45 no.2
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    • pp.251-275
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    • 2011
  • In this paper, we propose a novel kernel called a semantic parse tree kernel that extends the parse tree kernel previously studied to extract protein-protein interactions(PPIs) and shown prominent results. Among the drawbacks of the existing parse tree kernel is that it could degenerate the overall performance of PPI extraction because the kernel function may produce lower kernel values of two sentences than the actual analogy between them due to the simple comparison mechanisms handling only the superficial aspects of the constituting words. The new kernel can compute the lexical semantic similarity as well as the syntactic analogy between two parse trees of target sentences. In order to calculate the lexical semantic similarity, it incorporates context-based word sense disambiguation producing synsets in WordNet as its outputs, which, in turn, can be transformed into more general ones. In experiments, we introduced two new parameters: tree kernel decay factors, and degrees of abstracting lexical concepts which can accelerate the optimization of PPI extraction performance in addition to the conventional SVM's regularization factor. Through these multi-strategic experiments, we confirmed the pivotal role of the newly applied parameters. Additionally, the experimental results showed that semantic parse tree kernel is superior to the conventional kernels especially in the PPI classification tasks.

Understanding of foreign-born Korean Children's Early School Adjustment in the U.S - Language Development and Maternal Influences - (미국 내 거주하는 한국 국적을 가진 아동의 초기 학교 적응에 관한 연구 - 언어발달과 어머니의 영향 중심으로 -)

  • Seo SO-Jung
    • Journal of the Korean Home Economics Association
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    • v.43 no.5 s.207
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    • pp.131-147
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    • 2005
  • The purpose of this study was to provide a better understanding of foreign-born Korean children's early school adjustment in the U.S. The interaction between the foreign-born Korean children in the U.S. and several of the children's microsystems, including family, school, and peer was assessed to meet this purpose. The study subjects were 43 foreign-bom Korean children who were sampled from Korean Sunday Language schools and who attended local schools in the Boston area, MA, USA. Quantitative analysis was conducted to identify which variables of interest predicted the early adjustment of this group of children. Furthermore, in-depth interviews were conducted with mothers of the children from the top and bottom groups 1) the most successful (in the top quartile) and 2) the least successful adjustment groups (in the bottom quartile) sorted by scores on the Peabody Picture Vocabulary Test-Revised (PPVT-R). The interview results were analyzed to elicit maternal perceptions/beliefs on education, in general, and those of home-school relationships, in specific. Several conclusions can be drawn from both the quantitative and qualitative analyses. The results of multiple regression and path analysis showed that the children's language development predicted their adjustment, but the effects of the other two variables, peer relationships and school experiences, on the adjustment of children, were mediated through the children's language. Moreover, common themes and patterns in the responses to a series of open-ended questions emerged from the interviews with the two groups of mothers. The two mothers of the least successful group were concerned about their children's future and school success, but thev did not show anv responsive attitudes toward achieving this goal. By contrast, the mothers from the most successful group were self-determined with regard to their children's education and had strong beliefs and values on how to raise their children in the new culture. The implications were discussed.

Numerical Study of Settlement Reduction Ratio for the Bottom Ash Mixture Compaction Pile (수치해석적 방법에 의한 저회혼합다짐말뚝의 침하저감비에 관한 연구)

  • Chu, Ickchan;Kim, Gooyoung;Do, Jongnam;Cho, Hyunsoo;Chun, Byungsik
    • Journal of the Korean GEO-environmental Society
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    • v.13 no.3
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    • pp.53-58
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    • 2012
  • In general, sand compaction pile(SCP) method and gravel compaction pile(GCP) method have been mainly used to reinforce soft soils such as soft clay or loose sandy ground. But the sand compaction pile method has problems such as lack of sand supply and destroying the nature while collecting sand, the gravel compaction pile method has a problem such as decreased permeability of the drainage material due to clogging. Recently, the study to replace sand with bottom ash which has similar engineering properties with sand is in active. As a fundamental research on bottom ash mixture compaction pile utilizing bottom ash, its behavioral characteristics depending on granular materials and replacement ratio has been simulated numerically. In particular, Settlement Reduction Ratio(SRR) according to the distance from the center of pile was calculated. The main findings were as follows. Change values of Mixture Compaction Pile's SRR according to granular materials showed similar patterns and stiffness of the composite soil is increased depending on the replacement ratio so SRR showed decreased patterns. Especially, when the replacement ratio is in 20~40%, it increase significantly. When the replacement ratio is over 40%, it increase slowly. When considering the economics, 30~40% replacement ratio is appropriate.

Comparison of Short-term Mechanical Characteristics of Fine-grained Soils Treated with Lime Kiln Dust and Lime (석회노분과 석회로 처리된 세립토의 단기적 역학특성 비교)

  • 김대현;사공명;이용희
    • Journal of the Korean Geotechnical Society
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    • v.20 no.3
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    • pp.75-83
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    • 2004
  • The Indiana Department of Transportation (INDOT) has permitted the use of Lime Kiln Dust (LKD) as a low-cost construction material in creating a workable platform for soil modification (not for soil stabilization) since the early 1990s on selected projects. However, the enhanced strength of soils with LKD has not been accounted for in the subgrade stability calculations in the design process. This study was initiated to evaluate how the lime kiln dust is a comparable material to hydrated lime. A series of laboratory tests were performed to assess the mechanical benefits of lime kiln dust in combination with various predominant fine grained soils encountered in the State of Indiana, such as A-4, A-6 and A-7-6. In the course of this study, several tests such as the Atterberg limits, standard Proctor, unconfined compression, CBR, volume stability, and resilient modulus were performed. As a result, mixtures of fine grained soils with 5% lime or 5% LKD substantially improve unconfined compressive strength up to 60% - 400%. CBR values for treated soils are in the range of 25 to 70 while those for untreated soils range from 3 to 18. In general, significant increase in resilient moduli of the soils treated with lime and LKD was observed. This indicates that lime kiln dust may be a viable, cost effective alternative to hydrated lime in enhancing the strength of fine grained soils.