• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.2
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• pp.36-46
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• 2009

The objective of this study is to analyze the effect of artificial soil ground on a structure. When the artificial soil ground is planted, the technical factors to be considered will be the load for buildings and the growth of plants. There are no current studies of the effect of artificial soil ground on a structure and this study will analyze the load effects of artificial soil ground, which mixes both pearlite and natural soil on structures. The load affecting the structures due to artificial soil ground will be maximized when the artificial soil ground becomes saturated, and which would occur when the rainfall intensity exceeds the infiltration capacity of the artificial soil ground. In order to determine whether the artificial soil ground has reached saturation or not, a 10 years frequency and 10 minutes rainfall intensity which is used for in urban drain design, is utilized. The hydraulic conductivity of artificial soil and mixed soil has been changed depending on the proportion of the mix, It has a range of fluctuation in the degree of hardening, in particular, but does not exceed the 10 minutes rainfall intensity over 10 years frequency in the most cases. Therefore, it would be efficient to apply the saturated unit weight of artificial soil ground as the design load of a structure.

• Journal of Mushroom
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• v.13 no.3
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• pp.233-236
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• 2015

This report is the result of devising a method for utilizing the device of the load cell to maintain a constant water content of the medium every day to prepare a cultural substrates with the mixer for growing mushrooms bottle cultivation. A load cell was device under the medium mixer. It is developed when the device reaches the weight calculated as amount of substrate bottled and number of the bottle, it is automatically terminated by water injection. In addition, measuring the water content of each medium and the total weight of the medium reaches the target moisture content were calculated by using the program Cheong et al. (2015). Enter the total weight of the medium on the display unit of the load cell, when starting the water supply to reach the weight-based mixing media, the water supply is stopped. This method can improve the convenience by reducing the user's trouble in repeated work medium prepared by automating water supply. The suitable moisture content of the mixed medium for some kind of mushroom can be improved by the composition accuracy. And mycelial culture period, primordial period, mushroom growing period is maintained even of the medium can be produced stably. Therefore, it is possible to achieve a stable management of the mushroom farm according to mushroom quality and quantity stable throughout the year.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.1244-1247
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• 2002

The blending brake is mixed brake system which is operated by electrical and mechanical brake simultaneously. Most of urban transit system is used with blending brake unit. In order to train is align at the stopping position. The blending brake shall be presicely operated to the train. Many parameters are influence on the train when train is stopped on presicion position by blending brake. It is considered such parameters as decceleration, variable load, jerk, friction cofficient, etc. Therefore, This paper consider the parameter and describes the blending control for standard EMU. The control algorithm of it is proposed and simulation of it carried out by using MATLAB. Also Electronic control unit is manufactured with micro procesor which is configured fot blending control and is verified by performance test.

• International Journal of Concrete Structures and Materials
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• v.2 no.1
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• pp.35-39
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• 2008

This experimental study examines the applicability of polymer mortar permanent forms using a methyl methacrylate (MMA) solution of waste expanded polystyrene (EPS) to develop effective recycling processes for the EPS, referring to the flexural behavior of a polymer-impregnated mortar permanent form with almost the same performance as commercial products. An MMA solution of EPS is prepared by dissolving EPS in MMA, and unreinforced and steel fiber-reinforced polymer mortars are mixed using the EPS-MMA-based solution as a liquid resin or binder. Polymer mortar permanent forms (PMPFs) using the EPS-MMA-based polymer mortars without and with steel fiber and crimped wire cloth reinforcements and steel fiber-reinforced polymer-impregnated mortar permanent form (PIMPF) are prepared on trial, and tested for flexural behavior under four-point (third-point) loading. The EPS-MMAbased PMPFs are more ductile than the PIMPF, and have a high load-bearing capacity. Consequently, they can replace PIMPF in practical applications.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.11a
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• pp.1-26
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• 2002

This study addresses preliminary design and construction specification for micropiles. Especially several design methods for micropiles in sands, clays or mixed soil layers are described. The bearing capacity of micropiles are mainly depended upon the shaft resistance. Therefore, the pressure of grouting is one of the most important design parameters for the bearing capacity evaluation of micropile. There is no theoretical way to evaluate the shaft resistance of micropile up to now because grouting method is another key parameter for micropile design approach. Because of above reasons, the present design approaches of the micropile are based on the collected field data The bearing capacities of designed micropiles should be verified by static load tests before and after construction at the planned site.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.161-162
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• 2002

This study concerns the tribological behaviors of ultra-thin DLC coating with 3 nm thickness deposited in a mixed gas of argon + 20 % hydrogen as a function of humidity. Reciprocating wear tests employing a micro wear tester were performed under various normal loads and relative humidity in air environment. The chemical composition of the original and worn surfaces were studied by Auger electron spectroscopy (AES). It showed that the ultra-thin DLC coating exhibited low friction with enough wear stability at low normal load (0.18 N) and its tribological behavior was strongly dependent on the humidity. The sample surfaces before and after the test were examined using atomic force microscopy (AFM). Capillary force and meniscus areas were discussed in order to explain the influence of humidity on the friction force.

• Journal of Power System Engineering
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• v.13 no.2
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• pp.5-10
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• 2009

In recently, studies concerned to the diesel engine uses a natural gas as a fuel oil whose infra has been built already was approached to PCCI or HCCI with keeping a high thermal efficiency and reducing NOx and PM have been researching actively in normally single cylinder. An ignition source is required to bum the natural gas by a spark plug in gasoline engines, due to a higher auto-ignition temperature of natural gas. Then gas oil and DME were introduced as the ignition source. In this study as basic data for practical use of natural gas PCCI and HCCI engines, combustion characteristics and emission characteristics on 4-cylinders natural gas PCCI and HCCI engines with gas oil and DME as ignition sources were analyzed and the engine load range that is main object for practical use of PCCI and HCCI engines was made clearly by empirical experiment.

• Advances in aircraft and spacecraft science
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• v.1 no.3
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• pp.253-271
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• 2014

A linearised buckling analysis of thin-walled beams is addressed in this paper. Beam theories formulated according to a unified approach are presented. The displacement unknown variables on the cross-section of the beam are approximated via Mac Laurin's polynomials. The governing differential equations and the boundary conditions are derived in terms of a fundamental nucleo that does not depend upon the expansion order. Classical beam theories such as Euler-Bernoulli's and Timoshenko's can be retrieved as particular cases. Slender and deep beams are investigated. Flexural, torsional and mixed buckling modes are considered. Results are assessed toward three-dimensional finite element solutions. The numerical investigations show that classical and lower-order theories are accurate for flexural buckling modes of slender beams only. When deep beams or torsional buckling modes are considered, higher-order theories are required.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.347-352
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• 2002

Recent trends in the construction of building frame feature the increase use of composite steel concrete members functioning together in what terms of mixed structural systems. One of such systems, RCS(reinforced concrete column and steel beam) system is introduced and closely examined focusing on bearing strength of the composite joint in this paper. The main objective of this study was to develope one of details to increase bearing capacity while bearing failure is one of the two primary modes of failure in RCS system. Local bearing tests with specimens about 1/3 of the actual concrete column size were performed applying uniform load through steel plate with 100$\times$110mm size. Test results show that specimens with the bearing reinforcement detail developed in this study enhanced the bearing strength by 1.71~3.02 compared to concrete cylinder strength.

• International Journal of High-Rise Buildings
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• v.9 no.2
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• pp.167-173
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• 2020

W-Project is 60-story mixed-use residential building complex project in Daegu, the third biggest city in South Korea. There are lots explorable items to be solved to secure structural safety and meet the serviceability requirements. This paper describes what kind of structural system is optimized based on the architectural requirements and structural components design and the grade of concrete strength altered on floors. The defining process of lateral resisting system of outrigger compared to the core ratio of typical plan is illustrated in detail.