• Title/Summary/Keyword: 물리지수

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Effect of Satisfaction in Neighborhood Park Environments on Physical Activity and Health - The Case of Seongsan-gu and Uichang-gu in Changwon City - (근린공원 환경의 만족도가 신체활동과 건강에 미치는 영향 - 창원시 성산구와 의창구를 대상으로 -)

  • Park, Kyung-Hun;Lee, Woo-Sung;Kim, Tae-Hwan;Kim, Eun-Jung
    • Journal of the Korean Institute of Landscape Architecture
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    • v.42 no.3
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    • pp.64-75
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    • 2014
  • The purpose of this study is to analyze the effects of satisfaction in neighborhood park environments located in the Changwon-si of Gyeongsangnam-do, South Korea, on physical activity, the number of parks used for health improvement, and health levels based on Body Mass Index(BMI). Accordingly, a survey was conducted of 429 nearby residents and users of eight neighborhood parks located in urban areas of Seongsan-gu and Uichang-gu in the Changwon-si. The correlation between the environmental perception of neighborhood parks and physical activity and health, which was observed in the survey results, was analyzed using one-by-one linear regression analysis. By summarizing the study results, it was found that the primary reasons for avoiding park use were lack of time, time and effort required to reach the park(i.e., distance from the park), and lack of facilities within the park. Conversely, the primary reasons for using the park included accessibility, walking or strolling, leisure facilities, trees or shade, and diversity in exercise areas. In the case of park users, walking or strolling was the most common activity in the park. On average, park users walked to the parks for 10 minutes and exercised for an hour at least twice per week. With respect to the physical environment of the parks and surrounding areas, park users showed a high level of satisfaction with the distance between their houses and parks and the street environment. On the contrary, they exhibited low levels of satisfaction with water spaces and sightseeing within the parks. Subsequently, it was shown that the number of people using the parks for physical activities and health improvement was positively influenced(within a 5% significance level) by the intent to use the park for exercise, time spent in the park, satisfaction with park use and health improvement, distance to the park, and the convenience of using the park for the elderly. However, only the health improvement gained from park use was found to exhibit a correlation with BMI at the 10% significance level. Continuous accumulation of practical case studies on physical activities in parks and their health improvement effects is required. Through this, park spaces that are under the threat of reduction or elimination owing to various development plans can be conserved and expanded. Furthermore, such case studies can be used to provide data as the basis for deriving park plans and designs that improve parks' functions as sites of physical activity and health improvement.

The population characteristics of Nile tilapia (Oreochromis niloticus) in Dalseo Stream, South Korea (달서천에 서식하는 나일틸라피아(Oreochromis niloticus) 개체군 특성)

  • Wang, Ju Hyoun;Choi, Jun Kil;Lee, Hwang Goo
    • Korean Journal of Environmental Biology
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    • v.38 no.1
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    • pp.127-136
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    • 2020
  • This study was conducted to investigate the population characteristics of Nile tilapia (Oreochromis niloticus) in the Daegu Metropolitan City thermal effluent stream (Dalseo Stream) from January to November 2019. The collected fish were identified as 4,247 individuals of 20 species from a total of eight families. The dominant species was O. niloticus with 1,306 individuals and a high relative abundance (30.75%). The water temperature of Dalseo Stream was maintained above 10℃ throughout the year, which means that O. niloticus could inhabit it even in winter. The length-weight analysis showed a regression coefficient b of 3.1496, and a condition factor (k) of 0.0025 with a positive slope. Comparing the water temperature of Dalseo Stream and the total length of O. niloticus per investigation period, the 0-age individuals appeared May 29 when the water temperature was maintained above 22℃. In conclusion, the thermal effluent of Dalseo Stream allowed O. niloticus to survive in winter and maintain stable growth conditions and life cycles. The results of this study will inform ecological information on O. niloticus, which suggests that river management efforts should consider the management of O. niloticus populations for the conservation of fish species diversity.

Comparative Analysis of the New and Old Secondary School Science Textbooks (중학교 과학교과서의 비교분석)

  • Kim, Seong-Jin;Pak, Sung-Jae
    • Journal of The Korean Association For Science Education
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    • v.5 no.1
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    • pp.49-61
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    • 1985
  • In this study, I compared and analyzed the new and old secondary school science textbooks to find the charateristics of them and the differences between them. The results of the study are the following. Major concepts in the new textbook are almost similar to those in the old one. The-new textbook reinforces the functions of the introudction and checking the result of learning, and presents more and diverse learning materials and reduces the degree of learning difficulty by omitting the several abstract knowledges and mathematical formulas which can be understood through formal operational thinking. The results show that the new textbook is more effective in arousing student's interest and curiosity there fore it increases the efficiency of learning. But the new textbook is less suitable for inquiry because it is mainly composed of explanation and fact rather than experiment and observation. I think that this is the result from the actual approach to the real conditions of school when the curriculum was reformed and the new textbook was written.

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Estimation of Pesticide Leaching Potential Using GUS, RF and AF Index in Cheju Citrus Orchard Soils (제주도 감귤원 토양에서 GUS, RF, AF 지수를 이용한 농약의 용탈잠재성 평가)

  • Oh, Sang-Sil;Moon, Doo-Khil;Chung, Jong-Bae;Hyun, Hae-Nam
    • Korean Journal of Environmental Agriculture
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    • v.21 no.1
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    • pp.7-16
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    • 2002
  • Contamination of groundwater by agrochemicals used in the regional-scale Is now a major environmental problem, and this is especially true for Cheju island where virtually all potable water is from groundwater. The objective of this study was to assess leaching potential of eight pesticides in soils of citrus orchards using groundwater ubiquity score (GUS), retardation factor (RF) and attenuation factor (AF). Considering GUS estimated in 30 citrus orchard soils, metribuzin and metolachlor were classified as leacher, alachlor in volcanic ash soils and linuron in non-volcanic soils were classified as leacher, but chlorothalonil and chlorpyrifos were classified as non-leacher. For RF values, metribuzin was classified to be mobile in soils of low organic carbon, metolachlor and alachlor were classified to be moderately immobile in most soils, but linuron, diuron, diniconazole, chlorothalonil and chlorpyrifos were all classified to be very immobile. For AF values, diniconazole, chlorothalonil, and chlorpyrifos were classified to be very unlikely leachable in all of the soils, metribuzin was classified to be likely leachable, and metolahclor, alachlor, linuron and diuron were classified to be leachable only in non-volcanic soils. Although there were some variations in the relative potential of teachability of pesticides estimated with the three different indices, the ranking was essentially determined on the base of the intrinsic properties of the chemicals and environmental properties. Among the eight pesticides, metribuzin, metolachlor, and alachlor, which have high water solubility and low $K_{oc}$ values, have a significant leaching potential especially in non-volcanic ash soils of low organic carbon. But diniconazole, chlorothalonil, and chlorpyrifos, which have low water solubility and high $K_{oc}$ values, were classified to be very immobile in all of the soils. Therefore, to lower the possibility of pesticide contamination of the groundwater in Cheju island, those pesticides which have high water solubility and low $K_{oc}$ values should be used with care in soils of low organic carbon including non-volcanic ash soils.

Classification of Weathering for the Granite and Granite Gneiss in Okcheon Belt-Jecheon${\cdot}$Geumsan${\cdot}$Gimcheon in Korea (옥천대지역 -제천${\cdot}$금산${\cdot}$김천 - 에 분포하는 화강암 및 화강 편마암의 풍화분류에 관한 고찰)

  • Woo, Ik;Park, Hyuk-Jin
    • Economic and Environmental Geology
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    • v.37 no.3
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    • pp.355-364
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    • 2004
  • A study on the weathering grade classification has been performed for granite and granite gneiss in Korea. The qualitative classification criteria of weathering were reviewed and then modified with field studies for the weathered rock masses. The thin section observations and XRD analyses for the different weathering grades rock samples showed the petrographical and petrophysical difference with respect to the weathering : the proportion of weathering-resistant minerals suck at quartz and orthoclase has a tendency to increase with the development of weathering, but that of weathering-sensible minerals such as anorthite and biotite is decreased. The ranges of physical and mechanical rock properties for different weathering grades were obtained from the laboratory rock tests and field tests for the studied rocks. And then, along with $RDI_{sq}$(Fookes et al., 1988), the weathering index $I_{a}$, (Woo, 2003) has been developed in this study to demarcate the weathering grade. Those two indices rely mainly on the water absorption ratio of rock and on the different rock strength. The range of these weathering indices have been determined with the physical and mechanical rock properties that can be obtained from simple field or laboratory tests in 4 grades $I_{a}$> 7 for F, 3.5 < $I_{a}$ < 10 for SW, 1.0 $I_{a}$< 6.0 for MW and $I_{a}$< 2.5 for HW. Consequently, the weathering index could be utilized to classify quantitatively the rock weathering grade, especially for the studied granites and the granite gneiss in Korea.

Analysis of weighted usable area and estimation of optimum environmental flow based on growth stages of target species for improving fish habitat in regulated and non-regulated rivers (조절 및 비조절 하천의 어류 서식처 개선을 위한 성장 단계별 가중가용면적 분석 및 최적 환경생태유량 산정)

  • Jung, Sanghwa;Ji, Un;Kim, Kyu-ho;Jang, Eun-kyung
    • Journal of Korea Water Resources Association
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    • v.52 no.spc2
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    • pp.811-822
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    • 2019
  • Environmental flows in the downstream sections of Yongdam Dam, Wonju Stream Dam, and Hongcheon River were estimated with selected target fish species such as Nigra for the site of Yongdam Dam, Splendidus for the site of Wonju Stream Dam, and Signifer for the site of Hongcheon River by considering endangered and domestic species. Physical habitat analysis was performed to estimate environmental flows for the study sites by applying the Physical Habitat Simulation (PHABSIM) and RIVER2D which combined hydraulic and habitat models. Based on the monitored data for ecological environment, the Habitat Suitability Index (HSI) for the target species was estimated by applying the Instream Flow and Aquatic Systems Group (IFASG). In particular, based on the result of fish monitoring, the HSI for each stage of the growth for target species was analyzed. As a result, the Weighted Usable Area (WUA) was maximized at $4.9m^3/s$ of flow discharge during spawning, $5.8m^3/s$ during the period of juvenile, and $8.9m^3/s$ during the adult fish season at the downstream section of Yongdam Dam. The result of the Wonju Stream Dam showed an optimal environmental flow of $0.4m^3/s$, $1.0m^3/s$, and $1.5m^3/s$ during the period of spawning, juvenile, and adult. The habitat analysis for the site of Hongcheon River, which is a non-regulated stream, produced an optimum environmental flow of $5m^3/s$ in the spawning period, $4m^3/s$ in the juvenile stage and $6m^3/s$ in the adult stage.

Evaluation of Composting Characteristics According to the Air Supply Change in Farm-Sized Swine Manure (농가규모 양돈분뇨 퇴비화시 공기공급량 변화에 따른 퇴비 특성 평가)

  • Lee, Sunghyoun;Jeong, Gwanghwa;Lee, Dongjun;Lee, Donghyeon;Jang, Yuna;Kwag, Junghoon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.27 no.3
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    • pp.49-61
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    • 2019
  • Swine manure has been recognized as a organic sources for composting and many research was conducted to efficiently utilize and treat. This study was to evaluate a feasibility for producing swine manure compost under various treatment with mixture of swine manure and saw dust. Treatments were designed as follows; non aerated composting pile(REF), aerated composting pile of $100L/m^3$(EXP1), and aerated composting pile of $150L/m^3$(EXP2). The total days of fermentation were 28 days and each samples were collected at every 7 days from starting of composting. Temperature sensors were installed under 30~40cm from the surface of composting pile. Inner temperature in composting piles of EXP1 and EXP2 was rapidly increased to $67{\sim}75^{\circ}C$ within 1~2 days. The elevated temperatures found during the thermophilic phase are essential for rapid degradation of organic materials. While swine manure composted, moisture content, total nitrogen, EC of EXP1, EXP2 in sample at 28 days were lower than those of REF. But, pH and organic matter of EXP1, EXP2 in sample at 28 days were higher than those of REF. After finishing fermentation experiment, maturity was evaluated with germination test. Calculated germination index(GI) at REF, EXP1 and EXP2 were 23.49, 68.50 and 51.81, respectively. The values of germination index were higher at EXP1 and EXP2 which is aerated composting piles than REF which is non aerated composting pile. According to the results, composting process by aerated static pile compost had significant effect on the reduction of required period for composting. Supplying adequate amount of air to compost swine manure will greatly reduce composting period.

Establishment of the Suitability Class in Ginseng Cultivated Lands (인삼 재배 적지 기준 설정 연구)

  • Hyeon, Geun-Soo;Kim, Seong-Min;Song, Kwan-Cheol;Yeon, Byeong-Yeol;Hyun, Dong-Yun
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.6
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    • pp.430-438
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    • 2009
  • An attempt was made to establish the suitability classes of lands for the cultivation of ginseng(Panax ginseng C. A. Meyer). For this study, the relationships between various soil characteristics and ginseng yields were investigated on altogether 450 ginseng fields (150 sites in paddy and 300 sites in upland), across Kangwon, Kyunggi, Chungbug, Chungnam, Jonbug and Kyungbug Provinces, where ginseng is widely cultivated. In the paddy fields, most influential properties of soil on the ginseng yields was found to be the drainage class. Texture of surface soil and available soil depths affected the ginseng yields to some extents. However, the topography, slope, and the gravel content were found not to affect the ginseng yields. In the uplands, the texture of surface soil was most influential and the topography, slope, and occurrence depth of hard-pan were least influential on the performance of the crop. Making use of multiple regression, by SAS, the contribution of soil morphological and physical properties such as, topography, surface soil texture, drainage class, slope, available soil depth, gravel content, and appearance depth of hard-pan, for the suitability of land for ginseng cultivation was analyzed. Based on the results of above analysis, adding up all of the suitability indices, land suitability classes for ginseng cultivation were proposed. On top of this, taking the weather conditions into consideration, suitability of land for ginseng cultivation was established in paddy field and in uplands. As an example, maps showing the distribution of suitable land for ginseng cultivation were drawn, adopting the land suitability classes obtained through current study, soil map, climate map, and GIS information, for Eumsung County, Chungbug Province. Making use of the information on the land suitability for ginseng cultivation obtained from current study, the suitability of lands currently under cultivation of ginseng was investigated. The results indicate that 74.0% of them in paddy field and 88.3% in upland are "highly suitable" and "suitable".

The Applications of a Multi-metric LEHA Model for an Environmental Impact Assessments of Lake Ecosystems and the Ecological Health Assessments (호수생태계 환경영향평가를 위한 LEHA 다변수 모델 적용 및 생태건강성 평가)

  • Han, Jeong-Ho;An, Kwang-Guk
    • Journal of Environmental Impact Assessment
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    • v.21 no.3
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    • pp.483-501
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    • 2012
  • The purpose of this study was to apply a multi-metric model of Lentic Ecosystem Health Assessments(LEHA) for environmental impact assessments of Cheongpyung Reservoir during 2005 - 2006 and assessed the ecological model values. The ecosystem model of LEHA was composed of eleven metrics such as biological parameters($B_p$), physical parameters($P_p$), and chemical parameters($C_p$), and determined the rank of ecological health by the criteria. The variables of $B_p$ were metrics of % sensitive species($M_2$, NMS) and insectivore species($M_5$, % $I_n$), which decrease as the water quality degradates, and these metric values were low as 1.5% and 32.4%, respectively. In contrast, the proportions of tolerant species and omnivore species as the other $B_p$ parameters were 43% and 62%, respectively, which indicate a degradation and disturbance of the ecosystem. Riparian vegetation coverage($M_9$, % $V_c$) as a variable of $P_p$, were higher in the 2nd than 1st survey, and decreased toward the dam site from the headwaters. This was due to a habitat simplification(modifications) by frequent bottom dredging of sand and rocks. The variables of $C_p$ were two metrics of specific conductivity($M_{10}$, $C_I$) as an indicator of ionic contents(cations and anions) and the Trophic State Index(TSI) based on chlorophyll-a($M_{11}$, $TSI_{CHL}$) as an indicator of trophic state. These metric values of $C_p$ had high temporal variations, but low spatial variations on the main axis of the reservoir along with the ecological health of a good condition. The environmental impact assessments using the LEHA multi-metric model indicated that the model values of LEHA averaged 30.7 in 1st survey(fair - poor condition) vs. 28 in 2nd survey(poor condition), indicating a temporal variation of the ecological health. The model values of LEHA showed a minimum(28) in the lacustrine zone(S5) and ranged from 29 to 30 in the other locations sampled, indicating a low longitudinal variation. Overall, environmental impact assessments, based on LEHA model, suggest that chemical water quality conditions were in good, but biological conditions were disturbed due to habitat modifications by frequent dredgings in the system.

Determination of shear wave velocity profiles in soil deposit from seismic piezo-cone penetration test (탄성파 피에조콘 관입 시험을 통한 국내 퇴적 지반의 전단파 속도 결정)

  • Sun Chung Guk;Jung Gyungja;Jung Jong Hong;Kim Hong-Jong;Cho Sung-Min
    • 한국지구물리탐사학회:학술대회논문집
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    • 2005.09a
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    • pp.125-153
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    • 2005
  • It has been widely known that the seismic piezo-cone penetration test (SCPTU) is one of the most useful techniques for investigating the geotechnical characteristics including dynamic soil properties. As the practical applications in Korea, SCPTU was carried out at two sites in Busan and four sites in Incheon, which are mainly composed of alluvial or marine soil deposits. From the SCPTU waveform data obtained from the testing sites, the first arrival times of shear waves were and the corresponding time differences with depth were determined using the cross-over method, and the shear wave velocity profiles (VS) were derived based on the refracted ray path method based on Snell's law and similar to the trend of cone tip resistance (qt) profiles. In Incheon area, the testing depths of SCPTU were deeper than those of conventional down-hole seismic tests. Moreover, for the application of the conventional CPTU to earthquake engineering practices, the correlations between VS and CPTU data were deduced based on the SCPTU results. For the empirical evaluation of VS for all soils together with clays and sands which are classified unambiguously in this study by the soil behavior type classification Index (IC), the authors suggested the VS-CPTU data correlations expressed as a function of four parameters, qt, fs, $\sigma$, v0 and Bq, determined by multiple statistical regression modeling. Despite the incompatible strain levels of the down-hole seismic test during SCPTU and the conventional CPTU, it is shown that the VS-CPTU data correlations for all soils clays and sands suggested in this study is applicable to the preliminary estimation of VS for the Korean deposits and is more reliable than the previous correlations proposed by other researchers.

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