• Title/Summary/Keyword: environment condition

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Proposal of Models to Estimate the Coefficient of Permeability of Soils on the Natural Terrain considering Geological Conditions (지질조건에 따른 자연사면 토층의 투수계수 산정모델 제안)

  • Jun, Duk-Chan;Song, Young-Suk;Han, Shin-In
    • The Journal of Engineering Geology
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    • v.20 no.1
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    • pp.35-45
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    • 2010
  • The soil tests have been performed on the specimens obtained from about 1,150 sites including landslides and non-landslides areas in natural terrains for last 10 years. Based on the results of those tests, the average soil properties are estimated and the simple equations for estimating permeability are proposed according to geologic conditions. The average permeability in Granite and Mudstone sites is higher than other sites and the content of silt and clay in Mudstone and Gneiss sites is higher than other sites. The correlation analysis and the regression analysis were performed to estimate the coefficient of permeability according to geological conditions. As the result of the correlation analysis, the coefficient of permeability is selected as a dependent variable, and the silt and clay contents, the water contents and the dry unit weights are selected as independent variables. As the result of the regression analysis, the silt and clay contents and the void ratio were involved commonly in the linear regression equations according to geological conditions. To verify the proposed the linear regression equations, the measured result of the coefficient of permeability at other sites was compared with the result predicted with the proposed equations. As the result of comparison, there were a little bit different between them for some data. However the difference was relatively small. Therefore, the linear regression equations for estimating the coefficient of permeability according to geological conditions may be applied to Korean soils. However, these equations should be verified and corrected continuously to improve the accuracy.

Effect of Pollutants Control Measures in So-oak Watershed on the Control of Algae Growth in Daecheong Reservoir (소옥천 유역의 오염제어 대책에 따른 대청호 조류저감 효과 분석)

  • Park, Hyung Seok;Yoon, Sung Wan;Chung, Se Woong;Hwang, Hyun Sik
    • Journal of Environmental Impact Assessment
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    • v.25 no.4
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    • pp.248-260
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    • 2016
  • This study was aimed to assess the effect of diverse pollutants control measures suggested in the Chuso basin and its upstream of So-oak stream watershed where are the most concerned areas on the control of algal bloom occurring in Daecheong Reservoir. The control measures were classified as watershed measures and in-reservoir measures, and their effects were simulated using a two-dimensional hydrodynamic and water quality model. The watershed measures were made up of 1) point sources control, non-point sources control, and their combinations. The in-reservoir measures were supposed to treat sediment at Chuso basin and to install a phosphorus elimination plant (PEP) at the end of So-oak stream. The results showed that the effect of each measure was influenced by the hydrological condition of the year. In wet year, as the contribution of non-point sources increased, the non-point source control measures (NPS1~NPS4) showed more effective compared to other measures, while, the PEP system to eliminate phosphorus from So-oak stream showed better performance in dry year. In particular, the scenario of NPS1, in which all livestock manures were collected and treated but only chemical fertilizers (NPS1) were used for agriculture fields, showed the best performance for the control of algal bloom in Chuso basin among the watershed measures.

Habitat Characteristics and Distribution of Cymbidium kanran Native to Jejudo, Korea (제주한란의 자생환경 특성 및 분포에 관한 연구)

  • Lee, Jong Suk
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.7 no.1
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    • pp.40-49
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    • 2004
  • This work carried out to define the characteristic of Cymbidium kanran habitat at Mt. Halla in Jejudo, Korea from the ecological point of view including geological and topographical features, air and soil temperature, relative humidity, fluctuations of light intensity, habitat vegetation, distribution altitude, area limit, and etc. And another goal of this study consider the conservation counterplan of the cymbidium habitat. Natural distribution areas of the cymbidium were observed more abundantly on the well drained south and east-facing slopes. Soil acidity was ranged from pH 4.1 to 5.3, and electric conductivity was ranged from 176.4 to 299.9 us/cm (average 215.3 us/cm). Base-saturation percentage of the habitat soil was below 50%, bulk density 0.42g/$cm^2$, particle density 2.05g/$cm^2$, humus content 26%, total nitrogen 0.82%, available phosphate 4.2 mg/kg, exchangeable potassium 0.63 Cmol/kg, calcium 0.44 Cmol/kg and magnesium 0.67 Cmol/kg. Annual mean air temperature was $15.4^{\circ}C$, however, air temperature was ranged $11.7{\sim}18.2^{\circ}C$ in spring, $21.2{\sim}23.8^{\circ}C$ in summer, $12.8{\sim}22.0^{\circ}C$ in fall and $5.5{\sim}7.8^{\circ}C$ in winter season. Annual mean soil temperature at depth of 10cm was $13.2^{\circ}C$ And minimum value was recorded $4.7^{\circ}C$ on January, and maximum value $22.5^{\circ}C$ on August. Relative humidity was ranged 90.8~94.7% in summer, 80.8~91.5% in fall and 77.6~84.2% in winter season. Minimum value was 56.5% on December, and maximum value was 100% on July and August. Light intensities were ranged from 400 to 1,800 lux at the greater part of Cymbidium kanran sites in Jejudo. Summer regarded as an lower light intensities was recorded to be range of 500~600 lux; however, autumn and winter were shown higher light regimes ranged from 3,500 to 3,800 lux. Therefore, one must be suprised that the cymbidium grow at the light condition of 6 lux (minimum) or 10,000 lux (maximum). Tree species keeping higher frequency rate and density were Eurya japonica, Camellia japonica, Castanopsis cuspidata, Carpinus laxiflora and Pinus densiflora. Number of trees growing in a 5${\times}$5m quardrat was 35 as an average, and proportion of evergreen versus deciduous was 5:1. Distribution altitude of the orchid habitat was ranged from 120m (low) to 840m (high) from sea level on the south facing slope of Mt. Halla, and was ranged eastern borderline of Gujwaup, Bukjejugun to western boundaries of Jungmundong, Seogwipo city. For the stable conservation of Cymbidium kanran habitat, sunlight regimes must be increased more by means of cutting trees or twigs in the site.

Evaluations on Driver's Sensibility Changes by Sudden Start and Sudden Stop Conditions in Driving Simulator (자동차 시뮬레이터에서의 급출발 및 급제동에 따른 운전자 감성 평가)

  • 전효정;민병찬;성은정;김철중
    • Science of Emotion and Sensibility
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    • v.5 no.4
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    • pp.51-57
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    • 2002
  • The purpose of the study was to measure and compare driver's psychophysiological responses in different driving conditions through driving simulator. Twelve male adults(more than 1 year of driving experience) were assigned to four different driving conditions, such as normal speed(70㎞/h), sudden start(0㎞/h→70㎞/h), and sudden stop(70㎞/h→0㎞/h), and their simulator sickness, subjective pleasantness and arousal, EEG, ECG, skin temperature, and GSR were measured. Subjective and physiological evaluations were executed before and after driving in each condition. The results showed that subjective pleasantness and arousal increased in sudden stop and sudden start conditions, relative to stop and normal speed conditions. As the central nervous responses, beta wave increased and alpha wave decreased in sudden stop and sudden start conditions, relative to stop and normal speed conditions. With regard to the autonomic responses, heart rate and GSR increased, while skin temperature decreased in sudden stop and sudden start conditions, which means an activation of sympathetic nervous system. The results suggested that based upon observation of the distinctive psychophysiological changes by driving conditions, it is possible to evaluate the human sensibility in dynamic environment.

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A Study on Sound Design to Improve Regional Image -Focused on the Jeonju Area- (지역이미지 활성을 위한 사운드 디자인에 관한 연구)

  • Kim, Mee-Shuk;Chung, Sung-Whan;Hyoun, Sung-Eun
    • Science of Emotion and Sensibility
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    • v.10 no.4
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    • pp.613-622
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    • 2007
  • Recently, sound design is being made by corporations for the production as well as for marketing and web with consideration of image of productions and attributes to improve corporational image through the design of melody which would remain in users. And sound is becoming an important factor to establish the identity of each area such as life environment and public facilities. At present, our local governments are promoting active business like as CIP to improve urban image but there is a limit to establish identity as the result of its partial focus on visual sense or insufficient recognition about it. Jeonju, the place of sound, has many festivals and great meetings related with sound but it has not identity in the sense of sound. So the purpose of this study is to suggest the condition of sound which has the trait of Jeonju and to provide data for the trait to be used as a necessary element to establish identity in order to activate regional image. For the method of research, sampling Korean beautiful 100 sounds among the natural sounds of residents. most favorite as the samples of sound to search the sound of regional image. Selecting favorite samples among them and analyzed the factors through the questionnaire on the image of adjective in each sample. As the result of analysis, it has been shown that the factor of sound to reveal trait of Jeonju is the image of bright, delight, and cozy with consideration of harmony, dynamics, contrast, and culture. For this study is to provide data so it can be used to actively establish and identify the local image.

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A Study on the Utilization of Private Security for Preventing School Violence (학교폭력 예방을 위한 민간경비의 활용방안)

  • Jung, Eui-Lom
    • Korean Security Journal
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    • no.39
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    • pp.387-411
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    • 2014
  • School violence is now considered not only as a problem for a victim and a offender themselves, but also as a social problem that requires responsibilities of school, home, society, and even nation. Crimes and risk factors are various inside and outside of school. In terms of solving those problems, this study examines the actual condition of school violence among students. In addition, it is considered what efforts are conducted by police to establish a safe school environment and the problems that derive from it. Futhermore, this study aims to discuss the ways of using the private security with regard to dealing with school violence. In this society, the expectation of security service from the police is increased as time passed. However, police has limited resources, thus it is beyond their practice. Policing has changed from being monopolized by government to cooperating with various security agents. Community is not considered as the subject for enforcing the law anymore, but as the cooperator for effective policing. With regard to the limitation of police force, using the private security is an effective alternative. Therefore, it is required that private security should be assigned legal authority and shared information with schools in order to patrol the blind spot. Finally, school violence prevention efforts should be conducted by applying physical and electronic security.

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Research on the appreciation guidence of elementary school art subject -with present office teacher and an elementary school (5, 6 class) student as the central figure- (초등학교 미술과 감상지도에 관한 실태 조사 -현직교사와 초등학교(5, 6학년) 학생을 중심으로-)

  • Kang Kyoung-Koo
    • Journal of Science of Art and Design
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    • v.8
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    • pp.5-43
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    • 2005
  • This study aimed to suggest a resolution through a research on actual condition of appreciation class among art classes in elementary school. For this object, this study is about the need and problem of appreciation through concert of art appreciation and educational meaning. And this study is research, based on 200 current teachers to teach the art education of appreciation in Seoul. In the case of student research, this study show the current appreciation education focusing on 200 students in Seoul. The teachers has been seeing the importance of the appreciation education, but that education has been performing in the poor environment without aids and appreciation materials. And they thought that the most effective way to teach the appreciation of art is the on-site education such as the invitation of art-gallery or museum. The Change of realization about art, together with improvement of realistic situation, is important. But more important problem is the role and the realization of teacher who teach art directly. If the teacher's viewpoint to teach directly education of appreciation is examined, there are following problems First, it lacks realization about the importance of appreciation education. Teachers who teach a student have been taken functional art education mainly and this trend has been spread in the whole of society, therefore, the importance about the teaching of appreciation is negligent and is handled indifferently. Also, Teachers do not offer opportunity to obtain professional information of art appreciation map to overemphasize the study of practical teaching research. Second, elementary schools teacher is, for the most part, occasion that homeroom teacher teaches all object classes, and complete charge teacher is selected only some. Therefore, teacher in charge who play most a lot of subjects is difficult to recognize the importance of art teaching appreciation subject or class. There must have been a research about the educational preventive measures as suitable support, reorganization of at time and experts in superior office educational institution. Trough this study, I could know that front-line teacher should be specialized and more complete charge teacher should be needed urgently. Finally, the teachers must break the custom of the art appreciation and develop various art appreciation method. And the teachers have to lead the students to be interested art appreciation. That's what cultivate the students' aesthetic feeling and genius.

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The Effect of the Plasma Treatment on PLGA Scaffold for Adhesion and Chondrogenic Differentiation of Human Adipose-derived Stromal Cells (인체지방유래 간질세포의 부착 및 연골분화유도를 위한 PLGA 지지체의 플라즈마 처리 효과)

  • Dong, Chun Ji;Jun, Young Joon;Cho, Hyun Mi;Oh, Deuk Young;Han, Dong Keun;Rhie, Jong Won;Ahn, Sang Tae
    • Archives of Plastic Surgery
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    • v.33 no.1
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    • pp.46-52
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    • 2006
  • High-density micromass culture was needed to take three dimensions culture with ASCs(adipose derived stromal cells) and chondrogenesis. However, the synthetic polymer has hydrophobic character and low affinity to cells and other biomolecules. Therefore, the surface modification without changes of physical and chemical properties is necessary for more suitable condition to cells and biomolecules. This study was performed to investigate the effect of surface modification of poly (lactic-co-glycolic acid)(PLGA) scaffold by plasma treatment (P(+)) on the adhesion, proliferation and chondrogenesis of ASCs, and not plasma treatment (P(-)). ASCs were isolated from human subcutaneous adipose tissue obtained by lipectomy and liposuction. At 1 hour 30 minutes and 3days after cell seeding onto the P(-) group and the P(+) group, total DNA amount of attached and proliferated ASCs markedly increased in the P(+) group (p < 0.05). The changes of the actin under confocal microscope were done for evaluation of cellular affinity, at 1 hour 30 minutes, the shape of the cells was spherical form in all group. At 3rd day, the shape of the cells was fiber network form and finely arranged in P(+) group rather than in P(-) group. RT-PCR analysis of cartilage-specific type II collagen and link protein were expressed in 1, 2 weeks of induction. Amount of Glycoaminoglycan (GAG) markedly increased in P(+) group(p < 0.05). In a week, extracellular matrix was not observed in the Alcian blue and Safranin O staining. However in 2 weeks, it was observed that sulfated proteoglycan increased in P(+) group rather than in P(-) group. In conclusion, we recognized that plasma treatment of PLGA scaffold could increase the hydrophilic property of cells, and provide suitable environment for high-density micromass culture to chondrogenesis

On the Change of Hydrologic Conditions due to Global Warming : 2. An Analysis of Hydrologic Changes in Daehung Dam Basin using Water Balance Model (지구온난화에 따른 수문환경의 변화와 관련하여 : 2. 물수지 모형을 이용한 대청댐 상류 유역 수문환경의 변화 분석)

  • An, Jae-Hyeon;Yun, Yong-Nam;Yu, Cheol-Sang
    • Journal of Korea Water Resources Association
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    • v.34 no.5
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    • pp.511-519
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    • 2001
  • Global warming has begun since the industrial revolution and it is getting worse recently. Even though the increase of greenhouse gases such as $CO_2$is thought to be the main cause for glogal warming, its impact on global climate has not been revealed clearly in rather quantitative manners. The objective of this research is to predict the hydrological environment changes in the Daechung Dam basin due to the global warming. A mesoscale atmospheric/hydrologic model (IRSHAM96 model) is used to predict the possible changes in precipitation and temperature in the Daechun Dam basin. The simulation results of IRSHAM96 model and a conceptual water balance model are used to analyze the changes in soil moisture, evapotranspiration and runoff in the Daechung Dam basin. From the simulation results using the water balance model for 1x$CO_2$and 2x$CO_2$situations, it has been found that the runoff would be decreased in dry season, but increased in wet season due to the global warming. Therefore, it is predicted that the frequency of drought and flood occurrences in the Daechung Dam basin would be increased in 2x$CO_2$condition.

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Correlation between Phytoplankton Dynamics and Water Quality in Paldang Reservoir (팔당호에서 식물플랑크톤 군집 동태와 수질과의 상관성)

  • Han, Myung-Soo;Jheong, Weon-Hwa;Park, Jun-Dae;Kim, Jong-Min
    • Korean Journal of Ecology and Environment
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    • v.38 no.2 s.112
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    • pp.217-224
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    • 2005
  • This study was aimed to analyze the long-term fluctuation of water quality and phytoplankton dynamics of Paldang reservoir in Korea and to assess the relationship between algal bloom patterns and hydrological, limnological data. Diatoms in Paldang reservoir occurred continuously through the year. Blue- green algae occurred during the summer season (from June to Sept.), and the highest count was observed in July. Occurrence pattern of green algae was similar to that of blue-green algae. The rest of algae contained a lot of Cryptomonas spp. whose concentration was high from May to Aug. Dominant algal genera (>>7,000 cells $mL^{-1}$) in Paldang reservoir were Aulacoseira, Cyclotella, Microcystis, and Cryptomonas spp. Microcystis and Anabaena occurred during the summer season. Many different green algal genera were found in Paldang reservoir but their abundances were very low. There were some significant correlations (r>0.3, p<0.05) between algal taxa and water quality; diatoms and water temperature, TP:blue-green algae and water temperature, pH, DO saturation, COD, TP; green algae and water temperature, pH, DO saturation, COD, SS, TP. Furthermore, algal genera and water quality was significantly correlated (r>0.3, p<0.05) ; Aulacoseira and TN, TP; Anabaena and water temperature, DO saturation, COD, TP : Microcystisand water temperature, pH, DO saturation, TP; Coelastrum and COD, SS; Scenedesmus and water temperature, COD, TN, TP; Cryptomonas and DO saturation, TN. In Paldang reservoir, the water temperature had relatively big effect on blue-green algal bloom that was also dependant upon its hydrologic condition.