• Journal of Environmental Science International
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• v.26 no.5
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• pp.621-638
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• 2017

Meteorological characteristics related to variations in ozone ($O_3$) concentrations in the Korean peninsula before, during, and after Typhoon Talas (1112) were analyzed using both observation data and numerical modeling. This case study takes into account a high $O_3$ episode (e.g., a daily maximum of ${\geq}90ppb$) without rainfall. Before the typhoon period, high $O_3$ concentrations in the study areas (e.g., Daejeon, Daegu, and Busan) resulted from the combined effects of stable atmospheric conditions with high temperature under a migratory anticyclone (including subsiding air), and wind convergence due to a change in direction caused by the typhoon. The $O_3$ concentrations during the typhoon period decreased around the study area due to very weak photochemical activity under increased cloud cover and active vertical dispersion under a low pressure system. However, the maximum $O_3$ concentrations during this period were somewhat high (similar to those in the normal period extraneous to the typhoon), possibly because of the relatively slow photochemical loss of $O_3$ by a $H_2O+O(^1D)$ reaction resulting from the low air temperature and low relative humidity. The lowest $O_3$ concentrations during the typhoon period were relatively high compared to the period before and after the typhoon, mainly due to the transport effect resulting from the strong nocturnal winds caused by the typhoon. In addition, the $O_3$ increase observed at night in Daegu and Busan was primarily caused by local wind conditions (e.g., mountain winds) and atmospheric stagnation in the wind convergence zone around inland mountains and valleys.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.5
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• pp.1319-1332
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• 1995

Numerical analysis was performed to characterize the particle deposition behavior on a horizontal free-standing wafer with thermophoretic effect under the turbulent flow field. A low Reynolds number k-.epsilon. turbulence model was used to analyze the turbulent flow field around the wafer, and the temperature field for the calculation of the thermophoretic effect was predicted from the energy equation introducing the eddy diffusivity concept. The deposition mechanisms considered were convection, diffusion, sedimentation, turbulence and thermophoresis. For both the upper and lower surfaces of the wafer, the averaged particle deposition velocities and their radial distributions were calculated and compared with the laminar flow results and available experimental data. It was shown by the calculated averaged particle deposition velocities on the upper surface of the wafer that the deposition-free zone, where the deposition velocite is lower than 10$^{-5}$ cm/s, exists between 0.096 .mu.m and 1.6 .mu.m through the influence of thermophoresis with positive temperature difference of 10 K between the wafer and the ambient air. As for the calsulated local deposition velocities, for small particle sizes d$_{p}$<0.05 .mu.m, the deposition velocity is higher at the center of the wafer than at the wafer edge, whereas for particle size of d$_{p}$ = 2.0 .mu.m the deposition takes place mainly on the inside area of the wafer. Finally, an approximate model for calculating the deposition velocities was recommended and the calculated deposition velocity results were compared with the present numerical solutions, those of Schmidt et al.'s model and the experimental data of Opiolka et al.. It is shown by the comparison that the results of the recommended model agree better with the numerical solutions and Opiolka et al.'s data than those of Schmidt's simple model.

• ALGAE
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• v.31 no.1
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• pp.33-39
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• 2016

Blooms of macroalgae have grown over the planet in recent decades as a possible result of eutrophication of coastal waters. Visually, a bloom forming can be identified by dominant presence of an organism at the expense of others. In mid-January 2014, a forming bloom of red algae was detected on the beach of Garopaba, Santa Catarina State, Brazil. This aroused the interest of tourists and locals as well as the scientific community. Thus, the objective of this study was to characterize and quantify the photosynthetic floating organisms contributing to this phenomenon. In addition, we qualitatively compared algal composition of the bloom to those deposited in the post-beach area and the adjacent rocky shore community. Five sampling points in random patches of floating material were defined. At each point, five replicates were taken with a cube of 32,768 cm³, resulting in a total of 25 samples. Samples were collected in the inner area enclosed by a PVC quadrate of about 900 cm² from the shore and the specimens found in post-beach zone (wrack). Twenty-four taxa of macroalgae were found in the bloom, with Aglaothamnion uruguayense as the dominance one. Ten taxa were found on shore. Only four taxa were found in the post-beach area. The biomass estimated for A. uruguayense in the floating material was 8.35 tons with an estimated area of 52,770 m² . It is possible that this huge biomass value of the bloom is related to the local nutrient intake, and our results reinforce the necessity of coastal integrative management initiatives.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.1
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• pp.1-10
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• 2007

Coral reefs are among the most dynamic and various ecosystems on tropical ecosystem. They provide a large number of important ecosystem services. Despite their importance, they appear to be one of the most susceptible marine ecosystems. Dramatic decreasing of coral reefs has been reported from every part of the world. Indonesia contains 18% of coral reefs of world's total. Unfortunately the status of coral reefs in Indonesia is already in critical and poor condition. Coral reefs communities in Indonesia are subjected to a variety of environmental disturbance. Threats to Indonesia's coral reefs resources can be divided into two main types: anthropogenic and natural disturbances. The major anthropogenic disturbances on coral reefs in Indonesia are destructive fishing, pollution, coastal development, mining and harvesting live fish and coral, tourism. The natural disturbances such as cyclones, volcanic eruptions, earthquakes, tsunami and predator also contribute to coral reefs destruction in Indonesia. In my paper I tried to compare between natural and anthropogenic disturbances on coral reefs in Indonesia and raised these questions: (i) how the natural disturbances differ from anthropogenic area (ii) which type of disturbances has caused the greatest impact on coral reef ecosystem. My finding is that both of anthropogenic and natural disturbances give major impact on coral reefs in Indonesia. The important issue here is coral reef resilience could be disturbed by synergistic effects between various anthropogenic and natural disturbances. This phenomenon has significant conservation and management implication. The appropriate management should be conducted to protect coral reefs ecosystem in Indonesia. Mangrove management will succeed only when local people are involved and get sustainable benefits from mangrove ecosystem. Community based management and Integrated Coastal Zone Management (ICZM) are type of management that can be applied on coral reef ecosystems in Indonesia.

• Geomechanics and Engineering
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• v.12 no.6
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• pp.1003-1020
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• 2017

Estimation of groundwater inflow into underground opening is of critical importance for the design and construction of underground structures. Groundwater inflow into a pilot underground storage facility in China was estimated using analytical equations, numerical modeling and field measurement. The applicability of analytical and numerical methods was examined by comparing the estimated and measured results. Field geological investigation indicated that in local scale the high groundwater inflows are associated with the appearance of open joints, fractured zone or dykes induced by shear and/or tensile tectonic stresses. It was found that 8 groundwater inflow spots with high inflow rates account for about 82% of the total rate for the 9 caverns. On the prediction of the magnitude of groundwater inflow rate, it was found that could both (Finite Element Method) FEM and (Discrete Element Method) DEM perform better than analytical equations, due to the fact that in analytical equations simplified assumptions were adopted. However, on the prediction of the spatial distribution estimation of groundwater inflow, both analytical and numerical methods failed to predict at the present state. Nevertheless, numerical simulations would prevail over analytical methods to predict the distribution if more details in the simulations were taken into consideration.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.9
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• pp.17-26
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• 2011

Many types of services appear in a ubiquitous environment promulgated by the evolution of web service technology with the advances in wireless network technologies and mobile computing devices. These services differ according to their location environments, such as home, office, airport, and exhibition. It is required that a different set of services dynamically drops into the mobile user's device depending on their context and the distributed localized services are efficiently managed to seamlessly provide these localized services to the user. This paper proposes an Autonomic Service Composition System (ASCS) to provide useful services to the user with minimal or no effort for service selection. ASCS seamlessly installs the programs of localized services in the user's mobile device. It automatically provides localized services to users that are in the local service zone. Also ASCS can manage distributed localized services remotely and efficiently. ASCS is composed of a Remote Manager, Service Gateway, and Mobile Device. The prototype implementation uses 802.11b Wireless Network and Bundles using the OSGi Framework.

• Journal of Digital Convergence
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• v.13 no.4
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• pp.9-24
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• 2015

Purpose of this study is to develop the proceeding strategies for establishing of the DMZ World Peace Park in Korea which is one of projects of the Park Geun-hye's Government. We basically dissolute the conflict between the South and North Korea, and we build the atmosphere reconciliations and cooperation between two Koreas, and go forward the peaceful unification. And thus we make ultimately the world peace and establish enduring peace in the Korean Peninsula. Through the analysis the 8 proceeding strategies. Results of this study, I verified possibility of proceeding for establishing of the DMZ World Peace Park, and urgent need of policy development and support by the local governments, and we need to start the project in the South first.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.462-467
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• 2007

From the research which it sees verification of the whole interpretation and local interpretation of the durability steel deck bridge a static test and it produces the test body which it sells with character and it executes smallness pul lek detailed interpretation it leads and the appropriate characteristic of smallness pul lek detailed interpretation and to sleep a nominal stress price and it compares it judges it does. The stress quality from each structure region which it follows in load stock location it analyzes and from the hazard which evaluates, the objective region the length rib and the bottom grater weld zone, the length rib and width rib connection department and the width rib with the father it divided. It investigated the stress distribution of the test body from these objective location, FEM interpretation it led and the conduct against each structure state tax it analyzed. General conduct the load stock location the floor plate is located in the center with interpretation price together symmetry characteristic to seem, it cannot be like that it cannot there is one actual test price. Like this reason the length rib and width rib connection actually production even production characteristic security it is a day when it is impossible with the curvature junction department which it blows, it follows in examination body deferment condition and form feed with the fact that it is visible a big difference even with error of some it becomes. Consequently for a data and the research which are more accurate it is judged with the fact that the effort which is prudent will be necessary.

• 한국지구물리탐사학회:학술대회논문집
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• 2003.11a
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• pp.255-261
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• 2003

Tunnelling in poor and heterogeneous ground is a difficult task. Even with a good geological investigation, uncertainties with respect to the local rock mass structure will remain. Especially for such conditions, a reliable short-term prediction of the conditions ahead and outside the tunnel profile are of paramount importance for the choice of appropriate excavation and support methods. The information contained in the absolute displacement monitoring data allows a comprehensive evaluation of the displacements and the determination of the behaviour and influence of an anisotropic rock mass. Case histories and with numerical simulations show, that changes in the displacement vector orientation can indicate changing rock mass conditions ahead of the tunnel face (Schubert & Budil 1995, Steindorfer & Schubert 1997). Further research has been conducted to quantify the influence of weak zones on stresses and displacements (Grossauer 2001). Sellner (2000) developed software, which allows predicting displacements (GeoFit$\circledR$). The function parameters describe the time and advance dependent deformation of a tunnel. Routinely applying this method at each measuring section allows determining trends of those parameters. It shows, that the trends of parameter sets indicate changes in the stiffness of the rock mass outside the tunnel in a similar way, as the displacement vector orientation does. Three-dimensional Finite Element simulations of different weakness zone properties, thicknesses, and orientations relative to the tunnel axis were carried out and the function parameters evaluated from the results. The results are compared to monitoring results from alpine tunnels in heterogeneous rock. The good qualitative correlation between trends observed on site and numerical results gives hope that by a routine determination of the function parameters during excavation the prediction of rock mass conditions ahead of the tunnel face can be improved. Implementing the rules developed from experience and simulations into the monitoring data evaluation program allows to automatically issuing information on the expected rock mass quality ahead of the tunnel.

• Journal of Korean Society of Transportation
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• v.20 no.5
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• pp.23-31
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• 2002

The headway of vehicles entering an intersection is closely related with the saturation flow rate and is a basic parameter required for determining the saturation headway and the start-up lost delay. Since such headway value reflects the drivers' behaviors and features of the intersection, all intersections don't have an equal value, but are affected by number and location of their lanes, changing types, local characteristics and time zone. Accordingly, this study attempted to suggest proper values on the basis of data by investigating headway in lanes. Number of exclusive through lanes was divided into single lane, double lanes and triple lanes, the locations of lanes were divided into inside lane, central lane and outside lane. As a result of investigating the headway, single through lane, double through lanes-inside lane, and triple through lane-outside lane showed as 1.73 sec., 1.71 sec. and 1.93sec., respectively. The result of calculating the area factor of business areas by fixing 1.00 for the residental area and applying relation between headway and saturation flow rate was 0.96. In the case of start-up lost delay lead dual left turn and directional separation were 1.41 sec. and 3.27 sec., respectively, showing the great difference. Therefore, different start-up lost delay according to changing type should be applied.