• Title/Summary/Keyword: boundary characteristics

Search Result 3,206, Processing Time 0.027 seconds

The Environmental and Economic Effects of Green Area Loss on Urban Areas (도시지역에서의 녹지상실의 환경적 경제적 효과)

  • Kim, Jae-Ik;Yeo, Chang-Hwan
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.9 no.2
    • /
    • pp.20-29
    • /
    • 2006
  • Modeling urban climate caused by land use conversion is critical for human welfare and sustainable development, but has hampered because detailed information on urban characteristics is hard to obtain. With the advantage of satellite observations and the new statistical boundary system, this paper measures the economic and environmental effects of green area loss due to land use conversion in urban areas. To perform this purpose, data were collected from the various sources basic statistical unit data from the National Statistical Office, digital maps from the National Geographic Information Institute, satellite images, and field surveys when necessary. All data (maps and attributes) are built into the geographic information system (GIS). This paper also utilizes Landsat TM 5 imagery of Daegu city to derive vegetation index and to measure average surface temperature. The satellite data were examined using standard image processing software, ERDAS IMAGINE, and the results of the digital processing were presented with ARCVIEW(v.3.3). SAS package was used to perform statistical analyses. This study presents that there exists a strong relationship between land use change and climatic change as well as land price change. Based on results of the analysis, this paper suggests that planners should implement effective tools and policies of urban growth management to detect environmental quality and to make right decisions on policies concerning smart urban growth.

  • PDF

Characteristics of Isotherm, Kinetic and Thermodynamic Parameters for the Adsorption of Acid Red 66 by Activated Carbon (활성탄에 의한 Acid Red 66의 흡착에 대한 등온선, 동력학 및 열역학적 특성)

  • Lee, Jong-Jib
    • Clean Technology
    • /
    • v.26 no.1
    • /
    • pp.30-38
    • /
    • 2020
  • The kinetic and thermodynamic parameters of Acid Red 66, adsorbed by granular activated carbon, were investigated on areas of initial concentration, contact time, and temperature. The adsorption equilibrium data were applied to Langmuir, Freundlich, Temkin, Redlich-Peterson, and Temkin isotherms. The agreement was found to be the highest in the Freundlich model. From the determined Freundlich separation factor (1/n = 0.125 ~ 0.232), the adsorption of Acid Red 66 by granular activated carbon could be employed as an effective treatment method. Temkin's constant related to adsorption heat (BT = 2.147 ~ 2.562 J mol-1) showed that this process was physical adsorption. From kinetic experiments, the adsorption process followed the pseudo-second order model with good agreement. The results of the intraparticle diffusion equation showed that the inclination of the second straight line representing the intraparticle diffusion was smaller than that of the first straight line representing the boundary layer diffusion. Therefore, it was confirmed that intraparticle diffusion was the rate-controlling step. From thermodynamic experiments, the activation energy was determined as 35.23 kJ mol-1, indicating that the adsorption of Acid Red 66 was physical adsorption. The negative Gibbs free energy change (ΔG = -0.548 ~ -7.802 kJ mol-1) and the positive enthalpy change (ΔH = +109.112 kJ mol-1) indicated the spontaneous and endothermic nature of the adsorption process, respectively. The isosteric heat of adsorption increased with the increase of surface loading, indicating lateral interactions between the adsorbed dye molecules.

A Case Study on Impact Factor of Bridge in Tunnels Subjected to Moving Vehicle Load (터널내 교량의 이동차량하중 작용시 충격계수에 대한 사례연구)

  • 김재민;이중건;이익효;이두화
    • Tunnel and Underground Space
    • /
    • v.9 no.3
    • /
    • pp.185-193
    • /
    • 1999
  • This paper presents results of dynamic analysis for a bridge in intersection part of two tunnels subjected to moving vehicle load. Since such a bridge system is very unusual due to the fact that it is located in tunnel, the dynamic characteristics of the structure can not be assumed as conventional one. The structure investigated in this study it a reinforced concrete bridge in the intersection part of Namsan Tunnel-1 and Tunnel-2 in Seoul. It is supported by temporary steel structure which shall be constructed during the period of replacing lining in Tunnel-2. Dynamic analysis was carried out for the system using a finite element model constructed by general purpose FE program SAP2000. For this purpose, the structure, lining of tunnels, and surrounding rock were represented by finite elements, while the rock region it truncated and on its outer boundary viscous dampers were placed to simulate radiation of elastic waves generated tunnels. Several types of vehicle with various driving velocities were considered in this analysis. The FE model including vehicle loadings was verified by comparing calculated peak particle velocity with the measured one. From the analysis, the impart factor for the bridge was estimated as 0.21, which indicates that the use of upper bound for the impact factor in design code is reasonable for this kind of bridge system.

  • PDF

A Comparative Study of Structural Analysis on DCM Improved by Pile and Block Type (말뚝식과 블록식이 혼합된 시멘트혼합처리공법(DCM)의 구조체 해석 비교 연구)

  • Shin, Hyun Young;Kim, Byung Il;Kim, Kyoung O;Han, Sang Jae
    • Journal of the Korean Geotechnical Society
    • /
    • v.30 no.4
    • /
    • pp.5-19
    • /
    • 2014
  • In this study, the structural analysis is performed on the method of shallow block and deep cement mixing pile, and then their characteristics and associated behaviors were analyzed. In the case of continuous beam analysis, the predicted settlement was very small, and shear force and bending stress are somewhat overestimated. The frame method is similar to numerical analysis in the internal force shallow block and long pile, but because the settlement of pile is underestimated, the additional calculation using the reaction of the long pile is necessary. For soil arching method and piled raft foundation method, the excessive axial force of long pile was predicted because the load sharing of pile is very large compared to the other methods. In the behavior of the shallow block and deep pile method, the settlement of shallow block and contact pressure are much in the center than the edge. In the estimating method considering the interaction between improved material and ground, the load sharing of the soil-cement pile ranges from 20% to 45%, and the stress ratio is 2.0~5.0 less than piled DCM. The maximum member forces at the boundary conditions of pile head are similar, but in fixed head the axial force and vertical displacement are different in accordance with pile arrangement.

Development of Smart Multi-function Ground Resistivity Measuring Device using Arduino in Wind Farm (풍력 발전단지내 아두이노를 활용한 스마트 다기능 대지 고유 저항 측정 장치 개발)

  • Kim, Hong-Yong;Yoon, Dong-Gi;Shin, Seung-Jung
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.19 no.6
    • /
    • pp.65-71
    • /
    • 2019
  • Conventional methods of measuring ground resistance and ground resistance field measurement are used to measure voltage drop according to the resistance value of the site by applying current by installing a constant interval of measurement electrode. If the stratified structure of the site site is unique, errors in boundary conditions will occur in the event of back acid and the analysis of the critical ground resistance in the ground design will show much difference from simulation. This study utilizes the Arduino module and smart ground measurement technology in the convergent information and communication environment to develop a reliable smart land resistance measuring device even if the top layer of land is unique, to analyze the land resistance and accumulate data to predict the change in the age of the land. Considering the topographical characteristics of the site, we propose a ground resistance measuring device and its method of measuring ground resistance so that the auxiliary electrode can be installed by correctly positioning the angle and distance in measuring ground resistance. Not only is ground resistance value obtained through electrodes installed to allow accurate ground resistance values to be selected, but it can also be used as a useful material for installing electrical facilities in similar areas. Moreover, by utilizing reliable data and analyzing the large sections of the site, a precise analysis of the site, which is important in ground design as well as construction cost, is expected to be used much in ground facility design such as potential rise.

Perspectives on the Revitalization of Rural Village by Improving Management Scheme for the Dangsan Forest in Singeum Village, Goheung-gun (고흥군 신금마을 당산숲의 관리 개선을 통한 농촌마을 활력 제고방안 고찰)

  • Choi, Jai-Ung;Kim, Dong Yeob;Kim, Mi Heui;Ahn, Ok Sun
    • Journal of Agricultural Extension & Community Development
    • /
    • v.20 no.2
    • /
    • pp.535-554
    • /
    • 2013
  • This study was to investigate the characteristics and management condition of the Singeum village's Dangsan forest, and to seek the revitalization of rural village by improving management scheme. The Dangsan forest in Singeum-ri, Goheung-gun was composed of a Dangsan forest and a Bibo forest. The Dangsan forest was designated as natural monument # 362, and named 'Evergreen forest of Bongnae-myeon, Goheung'. The Dangsan forest area has been disturbed by the building of student training center. Even the local resident couldn't enter the forest due to the fence at the forest boundary except for Dangsan ritual which used to be serviced once a year. The Bibo forest was included in a beach area, and disturbed by lack of management. The Dangsan forest did not stay in good condition with various problems, such as wrong naming as a natural monument and misuse. The driving force of the Dangsan forest maintaining the beauty for several hundred years originated from the conservation of the forest with Dangsan ritual by local residents. Today, the Dangsan forest is in danger of being vanished and not regarded any more as a holy place due to inaccessibility for Dangsan ritual. The Dangsan forest in Singeum village needs to enhance its value as a traditional and cultural landscape, and improving the management scheme will contribute to revitalization of the village.

Geological and Geophysical Characteristics of the New Hebrides Basin (뉴헤브리디스 해분의 지질.지구물리학적 특징에 관한 연구)

  • Park, Chung-Hwa
    • Journal of the Korean earth science society
    • /
    • v.18 no.6
    • /
    • pp.559-564
    • /
    • 1997
  • The New Hebrides Basin is an inactive non back-arc basin located at the convergent boundary of the Pacific and Info-Australian plates. This basin was formed from 46 Ma to 60 Ma. The basin has two spreading episodes with rates of 34 mm/a for 42 to 47 Ma and 17 mm/a for 47 to 60 Ma. The sediments covered in the basin has uniform thickness of 0.65 sec. The age-depth correlation curve of the New Hebrides Basin can be represented by the following equation: $Depth(m)=2689+312\sqrt{Age}(Ma)$ The coefficient of 312 in this equation is close to that for major oceans, 350. This suggests that the cooling processes of the lithospheres in the New Hebrides Basin and major oceans are similar to each other. Free-air gravity anomalies of the basin varying from -22.3 mgal to +59.0 mgal. The mean value is +30.2 mgal higher than those of the normal oceans. Moderately large free-air gravity anomalies in the New Hebrides Basin are presumably owing to its location on a marginal swell along the New Hebrides Trench. It is generally observed that the ocean floor is very gently uplifted in a zone about 200 km oceanward of the trench axis. Positive free-air gravity anomalies amounting to $50{\sim}60$ mgal are usually observed on the crest of the swell. This topography is presumably by bending of the oceanic lithosphere so as to dynamically maintain nonisostatic states for some duration.

  • PDF

Petrogenetic Study on the Foliated Granitoids in the Chonju and the Sunchang Area(I) -In the Light of Petrochemical Properties- (전주 및 순창지역에 분포하는 엽리상화강암류의 성인에 대한 연구(I) - 암석지화학적 특성을 중심으로 -)

  • Na, Choon-Ki;Lee, In-Sung;Chung, Jae-Il
    • Journal of the Korean earth science society
    • /
    • v.18 no.6
    • /
    • pp.480-492
    • /
    • 1997
  • In order to understand the processes involved in the petrogenesis and the differentiation of the primary magma spectrum, a petrological and geochemical properties were investigated for the Chonju and the Sunchang foliated granites, which are located in the southwestern part of the Okchon zone and extends up to the northwestern boundary of the Ryongnam massif as two subparallel batholiths. Major element analyses show that the Chonju and Sunchang foliated granites are classified petrologically into a weakly to strongly peraluminous or calc-alkaline, but do not fit neatly into either of the I/S-type or magnetite/ilmenite-series classification schemes for granites, although the I-type and magnetite-series characteristics seem to be predominant based on the major element chemistry. In normative compositions, the Chonju granite is petrographically evolved from granodiorite to granite, whereas the Sunchang granite is from granodiorite to quartz monzodiorite. It seems to suggest a difference of the magmatic evolution processes such as crustal assimilation and/or fractional crystallization in magma. The REE patterns of both batholiths show high similarity and strongly fractionated REE distributions which show high $(Ce/Yb)_N$ ratios and little or no Eu anomalies. These REE patterns correspond broadly to those seen in the pre-Cretaceous granitoids of Korea. Apparently, the evidences obtained from the bulk compositions strongly suggest that the two foliated granitoids were formed by partial meltings of a relatively restricted and similar, may be common, source material which contains a continental crust component having an igneous composition, and have undergone a similar magmatic differentiation processes.

  • PDF

Theoretical Study on Fuel Savings of Marine Diesel Engine by Exhaust-Gas Heat-Recovery System of Combined Cycle (복합 사이클의 배기가스 열회수 시스템에 의한 선박용 디젤엔진의 연료 절약에 관한 이론적 연구)

  • Choi, Byung Chul;Kim, Young Min
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.37 no.2
    • /
    • pp.171-179
    • /
    • 2013
  • The thermodynamic characteristics of a combined cycle applied with a topping cycle such as a trilateral cycle at relatively high temperatures and a bottoming cycle such as an organic Rankine cycle at relatively low temperatures have been theoretically investigated. This is an electric generation system used to recover the waste heat of the exhaust gas from a diesel engine used for the propulsion of a large ship. As a result, when the boundary temperature between the topping and the bottoming cycles increased, the system efficiencies of energy and exergy were simultaneously maximized because the total exergy destruction rate (${\sum}\dot{E}_d$) and exergy loss ($\dot{E}_{out2}$) decreased, respectively. In the case of a marine diesel engine, the waste heat recovery electric generation system can be utilized for additional propulsion power, and the propulsion efficiency was found to be improved by an average of 9.17 % according to the engine load variation, as compared to the case with only the base engine. In this case, the specific fuel consumption and specific $CO_2$ emission of the diesel engine were reduced by an average of 8.4% and 8.37%, respectively.

Effects of Enzyme Complex on Odor Emission from Swine Slurry and Swine Buildings (효소복합체가 양돈슬러리 및 돈사 악취발생에 미치는 영향)

  • Jung, K.H.;Han, J.C.;Kwack, S.J.;Jung, J.D.;Lee, J.W.;Kim, D.H.
    • Journal of Animal Environmental Science
    • /
    • v.14 no.1
    • /
    • pp.15-22
    • /
    • 2008
  • This study was carried out to investigate the effect of enzyme complex on odor emission from swine slurry and the process of making swine liquid manure. Ammonia and hydrogen sulfide concentrations were significantly decreased by using the enzyme complex of liter per ton level of liquid swine slurry in the manure storage tank according to the time. Characteristics of liquid swine slurry were affected by the enzyme complex, total nitrogen and ammonia nitrogen contents were reduced compare with control. Ammonia and hydrogen sulfide concentrations in the finishing pig building and offensive odor compound on the boundary line of swine farm were significantly decreased by spraying in swine finishing building. In conclusion, the results obtained from this study suggest that using the enzyme complex of liter per ton level of liquid swine slurry for making liquid swine manure may improve the quality of swine liquid fertilizer and reduce odor emission. Also farm scale enzyme complex treatment may improve air quality in finishing pig building and deduce offensive odor compound of swine farm.

  • PDF