• KIEAE Journal
• /
• v.8 no.5
• /
• pp.77-83
• /
• 2008

Housing development, particularly apartment buildings, has been increasingly growing due to the construction promotion policy of the government since the 1980s. However such a volume-oriented policy results in unfavorable side effect of substandard quality and early deterioration in line with the expansion in volume. As part of measures to deal with the problems, rebuilding and remodeling have surfaced as alternative recently. Remodeling is expected to create the more benefits, compared to the rebuilding, in cost, efficiency and duration. To come up with the solution to such a challenge, it's necessary to analyze the influence factors of remodeling. Hence, the study was intended to compare the remodeling in the aspect of influence factors. The results of this study is expected to the propose of effectual management factors of the remodeling construction.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.27 no.10
• /
• pp.1516-1523
• /
• 2003

An inverse radiation analysis is presented for the estimation of the boundary emissivities for an absorbing, emitting, and scattering media with diffusely emitting and reflecting opaque boundaries. The finite-volume method is employed to solve the radiative transfer equation for a two-dimensional irregular geometry. A hybrid genetic algorithm is proposed for improving the efficiency of the genetic algorithm and reducing the effects of genetic parameters on the performance of the genetic algorithm. After verifying the performance of the proposed hybrid genetic algorithm, it is applied to inverse radiation analysis in estimating the wall emissivities in a two-dimensional irregular medium when the measured temperatures are given at only four data positions. The effect of measurement errors on the estimation accuracy is examined.

• Journal of Institute of Control, Robotics and Systems
• /
• v.3 no.2
• /
• pp.156-161
• /
• 1997

In this thesis, based on Genetic Algorithm, a new route search algorithm is presented to search an optimal route between the origin and the destination in intelligent route guidance systems in order to minimize the route traveling time. The proposed algorithm is effectively employed to complex road networks which have diverse turn constrains, time-delay constraints due to cross signals, and stochastic traffic volume. The algorithm is also shown to significantly promote search efficiency by changing the population size of path individuals that exist in each generation through the concept of age and lifetime to each path individual. A virtual road-traffic network with various turn constraints and traffic volume is simulated, where the suggested algorithm promptly produces not only an optimal route to minimize the route cost but also the estimated travel time for any pair of the origin and the destination, while effectively avoiding turn constraints and traffic jam.

• Journal of Animal Environmental Science
• /
• v.6 no.3
• /
• pp.161-168
• /
• 2000

The study exploited TAO system for the treatment of piggery slurry and aimed to draw characteristics and conditions of the reactor by differentiating the number of air input pump and foam cutter. The results are: 1. Under different operation condition, Run-3 with three air input pumps and four foam cutters showed the highest efficiency in the change of water level and temperature; 40-70cm and 45-55$^{\circ}C$, respectively. 2. Evaporation volume in Run-3 was the highest; 55.5l/$m^2$ . day in Run-1, 75.0/$m^2$ . day in Run-2, and 120.3/$m^2$ . day in Run-3. 3. Throughout the experimental period, temperature inside the reactor was maintained at around 5$0^{\circ}C$, regardless of seasonal temperature changes.

• Computational Structural Engineering
• /
• v.6 no.4
• /
• pp.107-118
• /
• 1993

New methods of visualizing the data from finite element analyses of 3-dimensional solids were developed in this study. Their efficiency and practicality were examined through their application and implementation into a finite element analysis software. The major effort of the study was to provide a way of representing data inside of volume, which is the most difficult problem in the postprocessing of 3-dimensional solids. Section representation, volume slice and separation, and isosurface representation were proposed for this purpose.

• Journal of Environmental Science International
• /
• v.12 no.7
• /
• pp.791-799
• /
• 2003

This study was carried out to get more operational characteristics of the sequencing batch biofilm reactors with media volume/reactor volume ratio of 15 %, 25 % and 35 %. Experiments were conducted to find the effects of the media packing ratio on organic matters and nutrients removal. Three laboratory scale reactors were fed with synthetic wastewater. During studies, the operation mode was fixed. The organic removal efficiency didn't show large difference among three reactor of different packing media ratios. However, from the study results, the optimum packing media ratios for biological nutrient removal was shown as 25%. The denitrifying PAOs could take up and store phosphate using nitrate as electron acceptor.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.05a
• /
• pp.587-590
• /
• 2002

Build-to-Order (BTO) capabilities enable manufacturing firms to design, produce, and deliver a high volume of differentiated products that meet specific customer needs in timely manner as well as at close to mass-production prices. Aim of BTO is to simultaneously achieve customer responsiveness, cost efficiency, and high volume production. This paper attempts to define the BTO system and suggests the critical components for its realization. A case study is also described to show the impact of a successful BTO implementation.

• Journal of Korean Society of Water and Wastewater
• /
• v.26 no.6
• /
• pp.735-745
• /
• 2012

Storage method is one of major measures for reduction of CSOs pollutant loads and several projects have been done nationwide. But systematic analysis of intercepting capacity has not been studied to determine optimum size of storage facility. In this research, not only storage volume but also intercepting capacity which means flow capacity from intercepting facility to CSOs storage facility was studied and optimum sizing method for storage facility was proposed. The result shows that pollutants reduction efficiency can be increased significantly by increasing intercepting capacity and it might reduce storage volume and total construction costs. Intercepting capacity for the study area was evaluated and it was shown as equivalent to 83 % probability rainfall intensity.

• Journal of the Korean Society for Precision Engineering
• /
• v.15 no.12
• /
• pp.21-27
• /
• 1998

This paper recommends the database construction for STL data and the new method of Delaunay's triangulation method in order to decrease volume errors by verifying STL file errors and modifying hole errors. Each vertex for the boundary coordinates of the verified hole errors was analyzed according to the following cases: planes or slow curves, edges, apexes, and rapid curves. In each case, a different modification process was adopted. With this method, most errors resulting from the conversion into the STL data as well as lots of volume errors arising from error modification were decreased.

• Journal of the Korean Society for Precision Engineering
• /
• v.26 no.7
• /
• pp.81-90
• /
• 2009

Due to environmental issues, the development of low energy consumption products has become one of the main topics in the home appliance industry. The energy consumption of a refrigerator depends on the efficiency of its compressor as well as on the refrigerator cycle design, such as the capacity modulation. In this study, a dual capacity, i.e., two-step capacity modulation (TCM), reciprocating compressor is developed. In a TCM compressor, capacity modulation is achieved by changing the dead volume in the cylinder. Instead of a concentric sleeve, an eccentric sleeve, a key, and a spring are used to change the dead volume for the clockwise and counterclockwise rotation of a motor. When the compressor changes its operating mode from full capacity to partial capacity or in opposite direction, the key may collide with the eccentric sleeve. The structural reliability and mode change reliability were confirmed by analysis and experiment.