• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.1221-1226
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• 2001

A structure gauge assessment is needed to ensure that a railway vehicle can run safely along a length of track without coming unacceptably close to lineside structures or equipment, or to vehicles running on adjacent tracks. This apparently straightforward question is in reality very complicated. The amount of space required for the safe passage of a railway vehicle is significantly greater than its static body profile for a number of reasons as follows: as the vehicle runs along the track, the track input excites the vehicle and it moves on its suspension. On curved track its geometric position leads to curve overthrows. A number of different approaches have been used to answer this question and some are described and specially applied to urban train by computer simulation in this paper. The program used for calculating the kinematic and swept envelope is the VAMPIRE made in U.K.

• Journal of the Semiconductor & Display Technology
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• v.19 no.3
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• pp.130-135
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• 2020

This paper describes the results of a study on the unmanned cleaning robot that performs the cleaning of the floating photovoltaic panels. The robot uses two SSC (Sliding Suction Cup) adsorptive devices to move up and down the slope. First, the forces generated when the robot moves up the slope are mechanically analyzed. The robot was designed and manufactured to operate stably by using the presented results. Next, the robot motion was tested on the inclined panel. It has been proven that robots are well designed and built to clean sloped panels.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.759-764
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• 1999

In intensive agriculture, exceeded chemical fertilizer application would increase the concentration of nitrate nitrogen in groundwater. Consequently, it could bring the eutrophication in lakes and streams. The present study examined runoff loading of nitrogen and phosphorus from the paddy field during non-cropping season. The runoff loading of total-N, ammonia-N, nitrate-N and total-P were 12.96kg/ha, 5.42kg/ha, 1.52kg/ha and 1.41kg/ha. When the runoff loading of nutrients was compared by runoff water and sediments. About 70-80% of total-N by runoff water and the rest 20-30% by runoff sediments were flowed into streams. But 60-70% of total-P by runoff sediments and the rest 30-40% by runoff water were flowed into streams. The phosphorus compounds, which were flowed into streams by runoff sediments and then sedimented, keep exchanging with water at water body in undelivered condition. And it moves gradually into water layer. This process can cause eutrophication continually and repeatedly in water environment. So, a sound program is needed to reduce soil erosion from farmlands.

• Structural Engineering and Mechanics
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• v.55 no.5
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• pp.901-911
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• 2015

The goal of this study is to investigate computational convergence of optimal solutions, with respect to optimality criteria (OC) method and methods of moving asymptotes (MMA) as optimization model for non-linear programming of material topology optimization using an acceleration method that makes design variables rapidly move toward almost 0 and 1 values. 99 line topology optimization MATLAB code uses loop vectorization and memory pre-allocation as properly exploiting the strengths of MATLAB and moves portions of code out of the optimization loop so that they are only executed once as restructuring the program. Numerical examples of a simple beam under a lateral load and a given material density limitation provide merits and demerits of the present OC and MMA for 99 line topology optimization code of continuous material topology optimization design.

• Journal of Mechanical Science and Technology
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• v.20 no.8
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• pp.1217-1223
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• 2006

Induction heating is a process that is accompanied with magnetic and thermal situation. This paper presents a simulation of a magneto-thermal coupled problem of an induction heating process for moving inductor coil. In the magnetic and thermal analyses, temperature-dependent magnetic and thermal material properties were considered. As the inductor coil moves in the process, solution domains corresponding to inductor changes into those of the air, and the solution domains of air change into those of the inductor. For these reasons, modeling of induction heating process is very difficult with general purpose commercial programs. In this paper, induction heating process for moving coil was simulated with the concept of traveling the position of the heating planes. Finite element program was developed and finite element results were compared with the experimental results.

• Journal of Ocean Engineering and Technology
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• v.18 no.6 s.61
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• pp.101-107
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• 2004

In this paper, the design criteria of future container crane for megaships are investigated. The current loading/unloading capacity of a typical container crane, roughly 30 moves/hr, is too law to meet the requirements of future super containerships, which are expected over 15,000 TEU. After examining the transition of containerships through the years and studying the research trend in developed countries, the specifications of the container crane that can Meet a 15,000 TEU containership are proposed. The structure, trolley and hoist mechanism, outreach, backreach, capacity, speeds, durability, and stability of the future container crane are described.

• Magazine of the Korean Society of Agricultural Engineers
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• v.42 no.2
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• pp.63-70
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• 2000

The present study was carried out for 7-months (from October 1.1997 to April 30. 1998) at a rice cultivation area blocked from livestock farming, farmstead and industrial complex to investigate the runoff loading of nitrogen and phosphorus in a plot(5,000$m^2$) paddy field areas. The runoff loading of total-N, amminia-N nitrate-N and total-P were 12.96kg/ha, 5.42kg/ha, 1.52kg/ha and 1.41kg/ha , respectively. When the runoff loading of nutrients was compared by dissolved and adsorbed forms, about 66% of total-N by dissolved form and the rest 34% by adsorbed form were flowed into streams. But 56% of total-P by adsorbed form and the rest 44% by dissolved form were flowed into streams. The phosphrous compounds , which were flowed into streams by runoff sediments and then sedimented, keep exchanging with water at water body in undelivered condition. And it moves gradually into water layer. This process can cause eutrophication continually and repeatedly in water environment . So, a sound program is needed to reduce soil erosion from farmlands.

• Journal of Korean Tunnelling and Underground Space Association
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• v.15 no.4
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• pp.387-400
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• 2013

In this study, the slope stability analysis and the landslide hazard assessment in tunnel portal slope were carried out. First, we selected highly vulnerable areas to slope failure using the slope stability analysis and analyzed the slope failure scale. According to analyses results, high vulnerable area to slope failure is located at 485~495 m above sea level. The slope is stable in a dry condition, while it becomes unstable in rainfall condition. The analysis results of slope failure scale show that the depth of slope failure is maximum 2.1 m and the length of slope failure is 18.6 m toward the dip direction of slope. Second, we developed a 3-D simulation program to analyze characteristics of runout behavior of debris flow. The developed program was applied to highly vulnerable areas to slope failure. The result of 3-D simulation shows that debris flow moves toward the central part of the valley with the movement direction of landslide from the upper part to the lower part of the slope. 3-D simulation shows that debris flow moves down to the bottom of mountain slope with a speed of 7.74 m/s and may make damage to the tunnel portal directly after 10 seconds from slope failure.

• Journal of the Korean association of regional geographers
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• v.13 no.6
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• pp.651-673
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• 2007

In the studies on residential move, there has been tendency of dichotomy where short distance moves are largely caused by housing to adjust to changes in households while long distance moves are induced by shift in labor market. However, some empirical studies have proven that residential move is so complex process that the simple dichotomy should be elaborated. In this sense, the present study seeks to identify compounded course of residential move in Korea. In determining migration history, families with younger householders, renters, householders with higher educational attainment and smaller households show a higher probability to move. In case of mobility, women were more prone to move compared to man. Women compared to man, older age augmented the probability to own a house after migration. Families with householders following an occupation of sales and technical service showed lowest tendency to own houses while it marked the highest in the group of professionals. Higher land price of a region was negatively related to owning houses after migration. The present study revealed that factors in macro level as well as micro level significantly affect the move of individuals with varying effects in accordance with migration history.

• Fashion & Textile Research Journal
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• v.14 no.6
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• pp.968-976
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• 2012

This study presents a new method called the SPMP (Semi-automatic profile measuring program) to efficiently measure body shape in elderly women. SPMP can automatically measure the angle of axis (19 items), surface (17 items), lengths (14 items), heights (16 items), widths (13 items), and depth (6 items). In total these 85 items are automatically measured very quickly, accurately, and easily after manually marking an initial 36 points. The utility of SPMP was evaluated using several tests. When SPMP measuring results were compared with manual methods (using a ruler and protractor) in thirteen elderly women using a paired t-test, there was no significant difference found between them. Furthermore, when measurements from SPMP were compared with actual measurement results in selected items from seven elderly women's measurements, smaller mean differences were found than those defined by ISO 20685, with the exception of the abdominal area which moves easily with breathing. Seven independent measurements of a single elderly woman were made by seven students using SPMP, and the values of coefficient of variation were less than 5% for all but 8 items. Finally, this study analyzed the correlation of all 85 item measurements, and found that the angle from the upper chest to the neck towards the front in the axis curved forward as much as the axis angle from the thigh to the waist (r=-0.876, $^{**}p$ < 0.01) bent backwards in elderly women. This detailed analysis helps to understand age-related changes in body posture, and will be useful in future studies.