• Journal of Wetlands Research
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• v.19 no.3
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• pp.296-302
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• 2017

Generally, a parking lot is constructed using asphalt or concrete. Such materials are impermeable, which means that a parking lot will directly release pollutants to any nearby water system during a rainfall event. An increased quantity of nonpoint source pollutants harms the ecohydrological system and causes further environmental damage leading to dysfunctional water circulation systems. Therefore, there is an urgent need for the design and application of Low Impact Development (LID) systems that allow more effective prevention of water circulation problems and management of nonpoint source pollution. This study aims to support such efforts by analyzing a permeable paver parking lot constructed using one of the LID techniques and comparing it to a conventional one in terms of the concentration of pollutants, nonpoint source pollution load and runoff rainfall lag effects during a rainfall event; it could serve as a reference for the construction of permeable paver parking lots in the future.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.4
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• pp.76-82
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• 2018

Grout in duct is very effective protection from tendon corrosion in PSC(Prestressed Concrete) structure. In the work, durability and mechanical tests are performed for two types of grout which are conventionally used one and the improved grout with reduced w/c (water to cement) ratio and silica fume. Tendon system with 1000mm height is prepared and various tests including strength, flow, absorption, and bleeding ratio are conducted. ICM(Impressed Current Method) is adopted for corrosion acceleration in tendon with 12.7mm diameter inside grout. For 2 and 4 days, corrosion acceleration is performed for 2 different type of grout and corrosion amount is investigated. The improved grout shows higher compressive strength by 10 MPa and lower absorption ratio by 50% than the conventional one. It also provides an excellent corrosion reduction to 39.8 %~48.2 % for 2~4 days of acceleration period.

• Korean Journal of Construction Engineering and Management
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• v.13 no.1
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• pp.53-66
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• 2012

Gangform compared with conventional wood and steel form is systemized form which has a capability to install and dismantle form at a time without repeating to assembly and disassembly small members. Gangform compared with ACS has some problems such as 1) Tower Crane load increase, 2) increase in safety incidence during climbing Gangform, 3) decrease in detachment operation productivity, 4) stop work due to climate impacts, and 5) decrease in labor cost, productivity, quality. A conceptual design model of automated Gangform climbing system is suggested for apartment housing construction to show its technical/economic feasibility and workers' safety while increasing operation productivity and concrete quality.

• Geotechnical Engineering
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• v.8 no.4
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• pp.5-16
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• 1992

The main purpose of this the sutdy is to develop the reinforced earth structure design method considering induced stresses and deflections resulting from placement and compaction of soil. In this paper, the new reinforcement Geolog developed by the author is also introduced which is being used as one of the effective earth reinforcing structure against compaction induced stresses. This study adopted the Seed's bilinear model in the estimation of the com paction induced stresses and compute the peak lateral stresses during compaction by doubled Boussinessq's elastic solution of mirror image theory, thereafter, calculate the residual compaction induced lateral stresses from the above peak lateral stress by the residual fraction. It is considered to be reasonable that the compaction induced stresses be added to the lateral earth pressures estimated from conventional gravity analysis considering the actual stresses during service life of the structures. "GEOLOG", a composite of steel bar and attached concrete stopper is found to be effective against tension and pull - out failure. In this paper, the design method considering the compaction induced stresses and the effect of Geolog reinforcement is suggested for the remforced earth structures where backkfill settlement on displacements are not allowed as in the cases of the bridge abutments or double faced reinforcement earth structures.tructures.

• Smart Structures and Systems
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• v.6 no.3
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• pp.277-290
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• 2010

Internationally the load carrying capacity of bridges is decreasing due to material deterioration while at the same time increasing live loads mean that they are often exposed to stresses for which they were not designed. However there are limited resources available to ensure that these bridges are fit for purpose, meaning that new approaches to bridge maintenance are required that optimize both their service lives as well as maintenance costs. Wireless sensor networks (WSNs) provide a tool that could support such an optimized maintenance program. In many situations WSNs have advantages over conventional wired monitoring systems in terms of installation time and cost. In order to evaluate the potential of these systems two WSNs were installed starting in July 2007 on the Humber Bridge and on a nearby approach bridge. As part of a corrosion prevention strategy, a relative humidity and temperature monitoring system was installed in the north anchorage chambers of the main suspension bridge where the main cables of the bridge are anchored into the foundation. This system allows the Bridgemaster to check whether the maximum relative humidity threshold, above which corrosion of the steel wires might occur, is not crossed. A second WSN which monitors aspects of deterioration on a reinforced concrete bridge located on the approach to the main suspension bridge was also installed. Though both systems have provided useful data to the owners, there are still challenges that must be overcome in terms of monitoring corrosion of steel, measuring live loading and data management before WSNs can become an effective tool for bridge managers.

• Culinary science and hospitality research
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• v.4
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• pp.211-224
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• 1998

This study is research about coinage and interpretation of Japanese Menus in luxury hotels in Seoul. Japanese Menus consist of three categories. These can be expressed A+B+C groupings. A represents Ingredients, C represents the cooking method, while B shows the name of a region(B1), the seasoning(B2), and a word that expresses the shape of the food(B3), etc. B can be flexible in meaning. However, the setting, A+B+C, is not always used strictly for these category meanings. Ingredients, A, is sometimes used independently(ex, ぃくとろろ), and at other times B1 + C, B2 + C or B3 + C are used. Sometimes A+C is used without B. The most general expression is Ingredients + the method for cooking(A+C Type). By knowing the menu description the food type and cooking method can be discovered. Most concrete method is Ingredients + procedure for seasoning + cooking method(A+B2+C Type) show how something is made and what kind of seasoning. This method is frequently used for roasted dishes with seasoning. Food which is expressed by A, Ingredients, does not require a complicated cooking process and is fixed by a conventional cooking process without any explanation ; delicacies(珍味), an hors d'oeuvres(前菜), sushi(Japanese vinegared rice delicacies) and sliced raw fish. There are two obstacles in interpreting Japanese Menus. First, we cannot look up the menu words easily in a dictionary because the mixing of Chinese Characters and the pronunciation of them differs from Korean chinese characters. Secondly, the names of Japanese food are inserted with a name of a place or another symbolic word, so they sometimes cannot be translated. We should offer various and accurate information for foreign customers because various Non-Japanese people use these restaurants frequently. This will enable them to enjoy themselves more comfortably. Therefore, you should decide the words carefully and provide an explanation about the complicated parts of the Menu when you work with Menu copywriter.

• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.3
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• pp.328-335
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• 2007

Ontology is represented by the shared concepts and relations among those. Many studies have been actively working on sharing human's knowledge with that of systems by using it. For a typical example, there is the design and implementation of ontology system for image understanding. However conventional studies on ontology-based image understanding have proposed not concrete methods but conceptual idea. In this paper, we propose an ontology-based image understanding system with following four processes: i)knowledge representation of a specific domain by the ontology, ii)feature extraction of objects through image processing and image analysis, iii)image interpretation by object features, and iv)reduction of ambiguity existing in image interpretation by ontology reasoning. We implement an image understanding system based on the proposed processed, and show the effectiveness of the proposed system from experimental results in a specific domain.

• Journal of the Korea Institute of Building Construction
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• v.15 no.2
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• pp.161-167
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• 2015

Nowadays, all the world face to the global warming problems due to the emission of $CO_2$. From the previous studies, recycled aggregates were used as an alkali activator in blast furnace slag to achieve zero-cement concrete, and favorable results of obtaining strength were achieved. In this study, gypsum and incineration waste ash were used as the additional alkali activation and effects of the gypsum and incineration waste ash to enhance the performance of the mortar were tested. Results showed that although the replacement ratio of 0.5% of incineration waste ash and 20% of anhydrous gypsum resulted in the low of mortar at the early age, while it improved the later strength and achieved the similar strength to that of conventional mortar (at 91 days).

• Geomechanics and Engineering
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• v.6 no.3
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• pp.293-320
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• 2014

In this study, in order to evaluate adequacy of considering local site effect, excluding soil-structure interaction (SSI) effects in inelastic dynamic analysis and design of mid-rise moment resisting building frames, three structural models including 5, 10, and 15 storey buildings are simulated in conjunction with two soil types with the shear wave velocities less than 600 m/s, representing soil classes $D_e$ and $E_e$ according to the classification of AS1170.4-2007 (Earthquake actions in Australia) having 30 m bedrock depth. Structural sections of the selected frames were designed according to AS3600:2009 (Australian Standard for Concrete Structures) after undertaking inelastic dynamic analysis under the influence of four different earthquake ground motions. Then the above mentioned frames were analysed under three different boundary conditions: (i) fixed base under direct influence of earthquake records; (ii) fixed base considering local site effect modifying the earthquake record only; and (iii) flexible-base (considering full soil-structure interaction). The results of the analyses in terms of base shears and structural drifts for the above mentioned boundary conditions are compared and discussed. It is concluded that the conventional inelastic design procedure by only including the local site effect excluding SSI cannot adequately guarantee the structural safety for mid-rise moment resisting buildings higher than 5 storeys resting on soft soil deposits.

• Journal of Korean Tunnelling and Underground Space Association
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• v.4 no.1
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• pp.45-55
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• 2002

From the early 1980's, the New Austrian Tunnelling Method (NATM) has been developed as one of the standard tunnelling methods in Korea. Approximately 10 years ago, wet-mix shotcrete with sodium silicate (waterglass) accelerator was introduced and widely used to tunnel lining and underground support. However, this accelerator had some disadvantages due to the decrease of long-term strength compared to plain concrete (without accelerator) and low quality of the hardened shotcrete. In order to compensate for these disadvantages, recently developed alkali-free accelerator has been successfully demonstrated in numerous projects and applications as a new material to make tunnels more durable and safer. An experimental investigation was carried out in order to verify the strength behavior of wet-mix Steel Fiber Reinforced Shotcrete (SFRS) with alkali-free accelerator. Compressive strength, flexural strength, and flexural toughness were measured by testing specimens extracted from the shotcrete panels. From the results, wet-mix SFRS with alkali-free accelerator exhibited excellent strength improvement compared to the conventional shotcrete accelerator.