• Ocean Systems Engineering
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• v.13 no.3
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• pp.247-268
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• 2023

Tidal stream energy extraction remains a site-specific resource due to the "first generation" criteria requiring high-velocity tidal streams. Most studies on tidal energy and turbine blade design heavily focus on installation sites with higher velocity conditions that are non-existent in tropical countries such as the Philippines. To shorten this gap, this review paper tackles tidal turbine design considerations for low-energetic regions such as the tropics. In-depth discussions of operating principles, methods of analysis, and designs of tidal turbine blades are presented. Notable tidal stream projects around the world are also mentioned in the paper. Also, it provides a perspective on the potential of this renewable energy to produce electricity for various sites in the Philippines. Finally, the paper emphasizes the need for new tidal turbine blade designs to be viable in tropical regions, such as the Philippines.

• Journal of the Korean GEO-environmental Society
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• v.15 no.6
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• pp.5-15
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• 2014

This study is to quantitatively evaluate the impact on surrounding groundwater of waterway tunnel excavation and cofferdam construction in which A-dam and B-dam, so prediction of groundwater fluctuation and tunnel lining installation was studied. As a result, drawdown of groundwater level during tunnel excavation and cofferdam construction occurred about 3.58 m in the tunnel shaft. The initial condition of groundwater level recovered by up to 90 % was simulated after the completed the construction of the tunnel and lining installation. Groundwater inflow in the tunnel evaluated was analyzed to have exceeding water design criteria of the tunnel. The groundwater inflow is reduced to maximum $0.006m^3/min/km$ after lining installation done in the tunnel, so effect of lining installation was evaluated as 93 % or more. Drawdown of about 0.04~0.31 m occurs in the houses and temples analysis of groundwater system of the surrounding area from construction. Drawdown has occurred nearly by considering annual groundwater level fluctuation of National Groundwater Observation Network.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.737-746
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• 2019

Most landslides in the country are shallow failures triggered by intense rainfall. Many researchers have revealed the possibility of predicting shallow failure through the volumetric water content (VWC). This study examined how to determine shallow failure using the gradient characteristics of the volumetric water content. For this, flume experiments were conducted using weathered granite soil. To confirm the saturation state of the surface layer under a rainfall intensity of 30 and 50mm/hr, VWC sensors were installed at depths of 10 and 20 cm on the upper, middle and lower slope. The test results showed that a shallow failure determination using VWC could be applied limitedly according to the slope degree. In addition, the effective cumulative rainfall due to the rainfall infiltration velocity is considered the main factor for the failure time. The failure prediction using the gradient of the VWC depends on the installation location and depth of the sensor. According to the experimental data, the measured value at 20 cm below the slope was most effective. Therefore, an analysis method of VWC and the method of selecting the installation location confirmed through this study can provide important data for presenting the measurement criteria using VWC in the future.

• The Journal of Sustainable Design and Educational Environment Research
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• v.14 no.2
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• pp.26-36
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• 2015

The new town was assumed that there is a difference between the country's elementary school environment. First, given the important elements of the school safety plan in order to verify this, and we plan to set up each of these elements by safety criteria. In the second chapter in order to achieve the objective of this study was to develop indicators to evaluate the safety of the school environment influences the safety of the school environment through the theoretical consideration. In Chapter 3, the difference in safety through the new elementary school survey of metropolitan areas was given a score per item per item depending on the evaluation criteria. The fourth section is the difference between safety school environment can be summarized as the following analytical results that the difference between the new city. The results of this study as follows: First, the characteristics of the elementary school environment showed a significant difference between the new town. Second, school location, terrain characteristics, bike paths and pedestrian to the installation, the safety of landscape installations, installing median barriers, traffic safety facilities, speed bumps, separation of pedestrian and vehicle circulation in the front door, scores of elements of the plan such as parking scheme there is a difference between the new town. Third, the introduction of elements of the plan such as Traffic calming or Traffic Island installation techniques was found lacking.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.6
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• pp.1073-1090
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• 2018

Since the domestic utility tunnels were built mainly in the development project of the new city, they are all in the form of cut-and-cover box tunnel. But, in the case of overseas construction of utility tunnels for existing urban areas, the bored tunnel types are mainly adopted. It is reasonable to install bored tunnels in a downtown area because it is difficult to block the roads or install bypass roads due to heavy traffic and civil complaints. In order to activate the utility tunnels in bored type, it is necessary to secure optimized cross-sectional design technology considering the optimal supplying capacity and mutual influencing factors (Thermal Interference, electrolytic corrosion, efficiency of the maintenance, etc.) of utilities (power cables, telecommunication cables, water pipes, etc.). The optimal cross-section design method for bored utility tunnels is ultimately to derive the optimal arrangement technique for the utilities. In order to develop the design methods, firstly, the cases of tunnel cross-section (Shield TBM, Conventional Tunneling) in overseas shall be investigated to analyze the characteristics of the installation of utilities in the section and installation of auxiliary facilities, It is necessary to sort out and analyze the criteria related to the inner cross-section design (arrangement) presented in the standards and guidelines.

• Korean Journal of Agricultural Science
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• v.38 no.1
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• pp.121-128
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• 2011

I/An electro-hydraulic transmission having advantages of convenience, safety, simple linking and high power, and an electronic control system were designed and fabricated. In this study, characteristics of the control system were investigated through outdoor tests for evaluation of installation of the system on a combine. Major findings were as followings. 1. Experiment for performance evaluation of the control system was conducted on concrete road. With steering lever in neutral position, driving HST swash plate and left/right wheel speed increased in proportion to driving lever angle. In case of steering control, steering swash plate angle changed in proportion to steering lever angle. This should cause increase in outer wheel speed, but it was observed that HST swash plate was controlled toward neutral to maintain the speed before steering. As a result, speed before steering was maintained despite the change in outer wheel speed by steering HST swash plate angle change. 2. It was observed that the HST system enabled steering with outer wheel maintained at constant speeds while inner wheel speed decreased, which was more stable than conventional mechanical links. In addition, for the selected 5 criteria, experiment showed satisfactory results and it was judged that installation on real vehicle would be feasible. 3. The control system showed response property of appropriate forward/reverse movement and lift/right steering, without causing any problems during experiment on concrete. Result of response property experiment on field operation also showed appropriate control over forward/reverse movement and left/right steering.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.5
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• pp.1122-1127
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• 2014

WLAN is affordability, flexibility, and ease of installation, use the smart device due to the dissemination and the AP (Access Point) to the simplification of the Office building, store, at school. Wi-Fi radio waves because it uses the medium of air transport to reach areas where security threats are always exposed to illegal AP installation, policy violations AP, packet monitoring, AP illegal access, external and service access, wireless network sharing, MAC address, such as a new security threat to steal. In this paper, signature-based of wireless intrusion detection system for Snort to suggest how to develop. The public can use hacking tools and conduct a mock hacking, Snort detects an attack of hacking tools to verify from experimental verification of the suitability of the thesis throughout.

• International Journal of Highway Engineering
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• v.13 no.2
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• pp.95-102
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• 2011

Anti-icing system can immediately respond when snowing is expected or the snow comes down on the road surface. It has been recognized that the system can reduce traffic accidents and congestion by quickly removing the frozen road surface area. However, it is very difficult to implement this system due to the expensive equipment installation and operation cost, Recently, there was a developed program for predicting the freezing area using three-dimensional model and tracking the sun path. But, there is no objective analysis method and all developed approaches are different so that the general standard of anti-icing system is needed. In this study, we proposed the decision criteria for determining application priorities of the anti-icing system based on weather and road conditions, i.e., geometric and topographic conditions. Regional climate survey, topographical analysis, and dynamic vehicle simulation considered road geometry and skid resistance was conducted to standardize the installation method of anti-icing system.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.6
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• pp.21-33
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• 2017

The purpose of this study is to find out that it can be provided as a basic data to increase the satisfaction with users in the placement and creation of the Green Buffer Zone. In this study, the research was started on the Green Buffer Zone in Gwanggyo new town, which was rebuilt as the zone to use according to the change of legal installation standard of the zone. The subject of this study is the Green Buffer Zone in Gwanggyo new town, which is expected to be completed in step 4 of 2016. As a result of analysing the location and use characteristics of the Green Buffer Zone, the following conclusions were made. First of all, it is categorized into two categories by Buffering / disaster prevention type and land to use adjustment type. Second, the buffer space of commercial space and housing is satisfying, but in commercial space, there is a need for a cushioning function and housing spaces require improvements in the functioning of the landscape. Third, the function of the Green Buffer Zone resets to cushioning function, disaster prevention function, landscape function, utilization function. and The installation criteria are proposed to environmental pollution, noise abatement, and planting trees, etc. Lastly, the future utilization plan considering the location and use characteristics of the Green Buffer Zone is as follows. In the planning stage, preference is given to the characteristics of use of arranging green facility. It is necessary to manage the planned facilities as much as possible by changing them if necessary. Construction stage, it restrictively reflects landscaping facilities within the Green Buffer Zone function. After stage, This study will prioritize the target areas and select necessary areas and need to make efforts to prevent indiscriminate greenery encroachment.

• Advances in Energy Research
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• v.5 no.2
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• pp.179-205
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• 2017

This research presents an in-depth analysis of location planning of the solar-hydrogen power plants for electricity production in different cities situated in Kerman province of Iran. Ten cities were analyzed in order to select the most suitable location for the construction of a solar-hydrogen power plant utilizing photovoltaic panels. Data envelopment analysis (DEA) methodology was applied to prioritize cities for installing the solar-hydrogen power plant so that one candidate location was selected for each city. Different criteria including population, distance to main road, flood risk, wind speed, sunshine hours, air temperature, humidity, horizontal solar irradiation, dust, and land costare used for the analysis. From the analysis, it is found that among the candidates' cities, the site of Lalezar is ranked as the first priority for the solar-hydrogen system development. A measure of validity is obtained when results of the DEA method are compared with the results of the technique for ordering preference by similarity to ideal solution (TOPSIS). Applying TOPSIS model, it was found that city of Lalezar ranked first, and Rafsanjan gained last priority for installing the solar-hydrogen power plants. Cities of Baft, Sirjan, Kerman, Shahrbabak, Kahnouj, Shahdad, Bam, and Jiroft ranked second to ninth, respectively. The validity of the DEA model is compared with the results of TOPSIS and it is demonstrated that the two methods produced similar results. The solar-hydrogen power plant is considered for installation in the city of Lalezar. It is demonstrated that installation of the proposed solar-hydrogen system in Lalezar can lead to yearly yield of 129 ton-H2 which covers 4.3% of total annual energy demands of the city.