• International conference on construction engineering and project management
• /
• 2015.10a
• /
• pp.501-502
• /
• 2015

Construction Standard Specifications, part of contract documents, has been improved through various amendments since their first enactment in 1967 up to the latest 2013 version. However, complaints about inconvenience and low availability have been continuously made in their structure and contents. Therefore, an improvement is needed based on the experts' opinions both from industrial and academic fields. This basic study is to compare the Korean specifications to those from the developed countries and derive the suggestions on their improvement. Furthermore, it aims to delve into the experts' opinion on the subject and identify the direction and priority for the improvement of the specifications. Through this study, user friendliness and efficiency are expected to be obtained in using the specifications.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2003.07a
• /
• pp.88-90
• /
• 2003

We reported an AC PDP structure with grooved front panel dielectric layer. The structure exhibits low breakdown voltage, better luminance, and better endurance to crosstalk in high Xe contents. It also shows less luminous efficacy then conventional structure because of the thinner dielectric layer, but we can apply the higher Xe contents to the grooved dielectric structure, which results in the higher luminous efficacy. We made experiments with the Xe contents from 4 to16% and total gas pressure from 400 to 600Torr. The grooved dielectric structure shows the improvement of 20% luminous efficacy and 17% luminance. The firing voltages lower about 40V at 600Torr and Xe 12, 16%. The discharge characteristics of grooved dielectric structure are verified also with 2D simulation.

• Journal of the Speleological Society of Korea
• /
• no.79
• /
• pp.53-63
• /
• 2007

While cave being active it will can occur and to be big the preparation against a small accident steadily and only objection the bay it knows to draw up the scenario of virtuality against the actual structure which leads a rescue work practice must practice. It systematizes a cave structure commission wheat cave structure association from the world-wide each nation and it does a cave relief activity. To found the cave structure center even in Korea and executing the improvement of structure setup and equipment and simultaneously, it is prevention of accident and accident occurrence right time and appropriate and to dispose and it is important to go out. The cave structure center must establish and inside Korean cave academic society it must maintain it must be strengthened feed with the fact that it becomes the relationship with academic society and the other cave structure specific authorization and a public relation.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.40 no.5
• /
• pp.148-159
• /
• 2012

The purpose of this study is to validate the effect of improvement such measures as fence installation or planting of bush and herbaceous plants taken from Pinus densiflora forest in Solbat Neighborhood Park in Seoul, which was damaged by stamping. The study was conducted in 2005 and 2010 in order to analyze changes in planting types, planting structure of Pinus densiflora forest, soil hardness, cross-sectional structure of soil, and physicochemical characteristics of soil. It was also measured by the growth of the branches and the diameter of Pinus densiflora, comparing before and after the improvement to study the effect of restoring Pinus densiflora forest damaged by stamping. When it comes to a change in planting type, Pinus densiflora forest without underlay was reduced from 48.5% in 2005 to 6.8% in 2010. Pinus densiflora forest with bush and herbaceous plants was increased dramatically from 7.4% to 46.8%. Regarding planting structure, in most area of the subject site, Pinus densiflora forest without under layer was transformed into the one with bush and herbaceous plants including Rhododendron mucronulatum, Rhododendron schippenbachii, Hemerocallis fulva, Aceriphyllum rossii, Hosta plantaginea growing in a wide area. The soil in the Solbat Neighborhood Park was very stiff with soil hardness of $54.8kg/cm^2$ in average. After the improvement efforts made in the Park in 2010, the soil hardness was mostly less than $4kg/cm^2$, being in a good condition with little influence on the growth of plants. When it comes to the cross-sectional structure of soil, litter layer didn't exist in 2005 because of stamping and the organic matter layer was only 1.0cm thick, which provided an unfavorable condition for plant growth. However, after improvement, litter layer was formed up to 3.0cm and thickness of the organic matter layer also went up to 1.5~8.0cm in 2010 because the damage from stamping was reduced. Concerning the physicochemical characteristic of soil, in 2005 soil showed pH 5.76~6.70, organic matter content 7.15~10.55%, and available phosphorus 9.38~26.47mg/kg, having no big problems as a soil environment for growth of Pinus densiflora. 15 trees of Pinus densiflora were selected to see branch growth and it was found that the branches tended to grow better after improvement. 70 trees of Pinus densiflora from various grades of soil hardness also were selected to identify changes of diameter growth. In most cases, it was analyzed that Pinus densiflora grew better after improvement. After conducting this study, it was validated that such measures as fence installation or planting of bush and herbaceous plants to restore Pinus densiflora Forest damaged by stamping were effective in improving growth of Pinus densiflora.

• Journal of the Korean Society of Safety
• /
• v.35 no.1
• /
• pp.53-61
• /
• 2020

This study proposes a new damper configuration for seismic performance improvement of heavy sliding facilities inside a building. For this purpose, we deal with two connection types of control system, and the parametric study has been performed to investigate their comparative seismic performances according to the variations of the control capacity. In order to simulate the seismic responses of the proposed system, we employed a recently-developed seismic response analysis method that can deal with the two-mass system with nonlinear frictional sliding behavior. The numerical results demonstrate that the typical method of diagonal bracing damper connection can exhibit effective control performance both on structure and the heavy sliding facilities, whereas the structure-facilities connection method does not show any control effect on both responses. On the other hand, the typical method has some limitations that it can adversely cause excessive sliding of the facilities, depending upon the frequency characteristics of structure and earthquake. On the contrary, the structure-facilities connection method is very effective in reducing the sliding displacement of the heavy facilities, even with small amount of control capacity. Thus, the following potential expectations can be inferred from these results: The typical diagonal bracing damper connection method will have some promising benefits in controlling the sliding facilities inside the building as well as the building itself, and the structure-facilities connection method can be a cost-effective way of protecting the internal heavy important facilities inside the structure already designed with sufficient seismic performance.

• Journal of the Korea Institute of Building Construction
• /
• v.14 no.1
• /
• pp.76-86
• /
• 2014

The cause of crack on reinforced concrete structures is varied, while the studies, which have intended to analyze this in the material side, have been the mainstream so far. Therefore, in this study, we intended to suggest the proposals for enhancement of the system to reduce crack and to improve the quality of the reinforced concrete structures, by reviewing the cause of crack mainly in the structural aspect and analyzing the practices and the system. The result has been shown as following. (1) As one of the measures for improving the constructional system related to the structure, it is to enhance the relevant system so that design on construction, structure, and equipment, can be separately ordered or jointly ventured, and the owner or the agent of the owner can discuss and mediate the business in each specialized field. (2) Importance on construction supervision and new establishment of regulations related to structure supervision.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.29 no.3
• /
• pp.33-42
• /
• 2006

From middle of 90's, SCM had emphasized the importance of connection of all companies which participate to a market, and outsourcing has emphasizes the slim structure of companies for pursing cost reduction and service improvement. But outsourcing as '2-1=1' and integration as '1+1=2' not adapt to the advanced market but return to the former state. Besides, it is impossible of subcontractors and logistics companies to execute these strategies which are win-win strategy and outsourcing. So many logistics companies have sharp competition in price recently. Therefore logistics companies have increased the need for a profitable business model and strategy. This paper researches the limitations of logistics market and redefines the role of logistics through the evolution of logistics. Also this paper proposes new role(Logister) and structure(Velcro structure) for not maker-oriented logistics but market-oriented logistics. The introductory case study will help to understand 2 terms(logister and velcro structure).

• Structural Monitoring and Maintenance
• /
• v.4 no.4
• /
• pp.351-364
• /
• 2017

In this study effects of various parameters like a number of bays, the stiffness of the structure along with the height of the structure was examined. The fundamental period of vibration T of the building is an important parameter for evaluation of seismic base shear. Empirical equations which are given in the Indian seismic code for the calculation of the fundamental period of a framed structure, primarily as a function of height, and do not consider the effect of number of bays and stiffness of the structure. Building periods predicted by these expressions are widely used in practice, although it has been observed that there is scope for further improvement in these equations since the height alone is inadequate to explain the period variability. The aim of this study is to find the effects of a number of bays in both the directions, the stiffness of the structure and propose a new period equation which incorporates a number of bays, plan area, stiffness along with the height of the structure.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1996.05a
• /
• pp.239-243
• /
• 1996

In this paper, we have tried to focus on the optimum conditions of crystal structure parameters on YBCO high Tc oxide-superconductor as an excel lent electronic parts. When we verify the characteristic improvement of superconductance and accurate reproduction and so forth, we have made use of RIETAN. We have varied the lattice constant with oxygen content from 6.0 to 7.0 as for transition of orthogonal structure and tetragonal structure for the superconductor. As the result of above, we have preyed that transition from orthogonal structure to tetragonal structure is made at the point of 6.6(oxygen content) by using the simulation.

• Journal of the Korean Society of Visualization
• /
• v.17 no.2
• /
• pp.17-24
• /
• 2019

The purpose of this study is to study the fluid-dynamic and structural characteristics of the conventional greenhouse and to find possible improvement on the current greenhouse. The greenhouse is required to have enough rigidity of the structure while the installation and reinforcement should be as easy as possible. In this study, the structural stability to the snow load was tested through the computational structure analysis based on the building structure standard, and the wind load was computed by computational fluid-structure interaction analysis. The current analysis can be used as a reference data for a new greenhouse and it will be economically viable by reducing installation and maintenance costs.