• Fibers and Polymers
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• v.7 no.4
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• pp.358-366
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• 2006

Thermotropic liquid crystal polymer (TLCP)-reinforced poly(butylene terephthalate) (PBT) composites were prepared by melt processing. The improvement in the mechanical properties and the processability of the PBT/TLCP composites was attributed to the reinforcing effect by TLCP phase and its well distribution in the PBT matrix. X-ray diffraction results demonstrated that a slow cooling process leads to the thicker lamellar structures and the formation of more regular crystallites in the composites. The incorporation of TLCP improves not only the tensile strength and flexural modulus but also the heat distortion temperature (HDT) of the PBT/TLCP composites. The HDT values of the composites were dependent on TLCP content. The improvement in the HDT values of the PBT/TLCP composites may be explained in terms with the increased flexural modulus, the development of more regular crystalline structures, and the enhancement of the ability of the composites to sustain the storage modulus by TLCP phase. In addition, the simple additivity rule makes it possible to predict the HDT values of the PBT/TLCP composites.

• Journal of the Economic Geographical Society of Korea
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• v.10 no.3
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• pp.304-318
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• 2007

This study aims to assess an effectiveness of the revitalization policy of traditional market which has been put in force since the late 1990's through a case study of Gyeongbuk province in Korea. According to a qualitative assessment of the improvement project of market facilities and the modernization project of marketing technique, each project has little effect. This seems to be caused by the existing revitalization policy without full considerations of reinforcing the spatial competitiveness of traditional markets. This study suggests an alternative of the revitalization policy of traditional markets concentrating on the spatial competitiveness of them.

• Journal of the Korean Geosynthetics Society
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• v.6 no.4
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• pp.7-13
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• 2007

When the structure such as roadway, railway are constructed on abandoned coal mine area, the countermeasure to prevent settlements is necessary. In this study, numerical analyses are performed to evaluate the effect of the various countermeasures. As a results, the method which is filling the coal mine is more effective than that of reinforcing the ground above the coal mine. The ground settlement decreases hyperbolically with increasing the filling ratio of the coal mine. Also, the relationship between the filling ratio and the settlement reduction ratio is discussed precisely.

• Journal of the Korean Geosynthetics Society
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• v.7 no.4
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• pp.25-36
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• 2008

This paper presents the results of numerical investigation on support mechanism of geogrid-encased stone columns for use in soft ground. A number of cases were analyzed using a axial-and 3D stress-pore pressure coupled model that can effectively model construction sequence and drainage as well as reinforcing effects of geogrid-encased stone columns. The results indicated that the geogrid encasement tends to significantly improve the load carrying of a stone column. Also revealed was that such a confinement effect depends on encasement length and stiffness of geogrid. It is also shown that there exist critical encasement length and stiffness of geogrid for a given condition.

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.2
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• pp.147-154
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• 2005

It is found that as contents of chloride ion and age increase, area of corrosion also increases. Inare increased to 1035 days from 730 days, slope of increase of corrosion area is greatest. Non-rust inhibitor specimens show corrosion area of 8~35 times more than rust inhibitor specimens and anticorrosive effects by application of rust inhibitor can be confirmed. When chloride ion is not contained, corrosion control effects of steel reinforcing according to increase of thickness are found, but specimens having chloride ion show no regular tend of thickness and corrosion due to complex problems such as reverse diffusion of chloride and test errors.

• Korean Journal of Occupational Health Nursing
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• v.20 no.1
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• pp.35-45
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• 2011

Purpose: The purpose of this study was to propose and to test a predictive model that could explain the workers' quality of life. Methods: Data were collected using self-report questionnaires from 901 workers in Daejeon, Korea. The questionnaires included nine measured variables (safety culture, self-efficacy, activity of occupational health provider, knowledge in occupational health, age, health promotion behavior, workplace environment, health level, and quality of life), as revised PRECEDE model has suggested. The collected data were analyzed using SPSS/WIN 15 and AMOS 6.01 version. Results: Based on the constructed model, behavior, environment, and health were found to have significant direct effect on quality of life. Indirect factors were perceived biological, predisposing, reinforcing, and enabling. The proposed model was concise and extensive in predicting quality of life of the participants. The final modified model yielded GFI=.85, AGFI=.89, NFI=.79, and RMSEA=.11 and exhibited good fit indices. Conclusion: Findings of this study may contribute to development of effective nursing interventions for promoting quality of life in workers.

• International Journal of Concrete Structures and Materials
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• v.10 no.4
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• pp.407-424
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• 2016

This study tests ten full-size simple-supported beam specimens with the high-strength reinforcing steel bars (SD685 and SD785) using the four-point loading. The measured compressive strength of the concrete is in the range of 70-100 MPa. The main variable considered in the study is the shear-span to depth ratio. Based on the experimental data that include maximum shear crack width, residual shear crack width, angle of the main crack and shear drift ratio, a simplified equation are proposed to predict the shear deformation of the high-strength reinforced concrete (HSRC) beam member. Besides the post-earthquake damage assessment, these results can also be used to build the performance-based design for HSRC structures. And using the allowable shear stress at the peak maximum shear crack width of 0.4 and 1.0 mm to suggest the design formulas that can ensure service-ability (long-term loading) and reparability (short-term loading) for shear-critical HSRC beam members.

• Journal of the Korea Institute of Building Construction
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• v.1 no.1
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• pp.143-150
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• 2001

Permanent-Form is one of system forms for reducing human labor, work costs, oscillation, noise, construction wastes and so on. Permanent-Form is made from precast method in facilities, and carried in construction site to assemble with no demolding. The biggest expense to produce permanent-Form is about manufacturing mold. This papers about structural efficiency evaluation, construction efficiency test. The result of this study is below. (1) In the compressive strength test of column. Fly ash specimen and polymer specimen's strength developed as each 8%, 14% to comparison with standard specimen. The reason of this result from form section area increase and form's reinforcing bar (2) The Degree of column crack in permanent form is lower than another one's The glass fiber's fiber reinforcement effect brings like this. (3) In the flexural load test of beam, the early crack load and maximum load of permanent form use specimen showed 20% higher than standard specimen's. (4) In field application experiment, an constructional error is satisfied with the allowable margin of error, $\pm$5mm (5) When the concrete is placed into the form inside, The transformation degree of permanent form is lower than plywood form's. (6) The concrete packing ability of permanent form is satisfactory. (7) The bonding strength of permanent form shows enough strength - 6kgf/$\textrm{cm}^2$.

• Composites Research
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• v.14 no.4
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• pp.27-34
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• 2001

The finite element method based on the total Lagrangian description of the motion and the Hellinger-Reissner principle with independent strain is applied to investigate the nonlinear behavior and vibration characteristics for patched reinforced laminated spherical panels. The patched elements are formulated using variable thickness at arbitrary point on the reference plane. The cylindrical arc-length method is adopted to obtain a nonlinear solution. The post-buckled vibration is assumed to be small amplitude. The effect of patch in the spherical shell Panel is investigated on the nonlinear response and the fundamental vibration characteristics. The present results show that the load-carrying capability can be improved by reinforcing patch. The fundamental frequency of patched panel is lower than that of equivalent shell panel. However, the fundamental frequency of patched panel does not decrease greatly due to the increase of nonlinear geometrical stiffness under loading.

• Korean Journal of Health Education and Promotion
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• v.16 no.1
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• pp.127-135
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• 1999

The purpose of this study was to verify the effects of the developed exercise prescription program by utilizing PRECEDE(Predisposing, Reinforcing, and Enabling Causes in Educational Diagnosis and Evaluation} model on adult's knowledge related to health, attitudes, behaviors and serum lipoprotein values. This study employed 20 males(40-47 yrs) without any apparent physical defects, who did not experience such physical activities. They were divided into experimental groups and control groups, each group consisted of 10 subjects who performed Jogging. The experimental design of the study utilized “two-way ANOVA Design” conducted by the repeated measurement two time(pre and post-test). As the results of the data, the conclusions were as follows: 1. There were statistically significant effects of the health module exposed to the experimental groups on the higher means of knowledge score in the experimental groups than those in the control groups. 2. There were statistically significant effects of the module exposed to the experimental groups on the positive changes of their attitudes. 3. There were significant changes on the behaviors of the health by doing the health program. Therefore the developed health program formed the improved knowledge about the health and the desirable attitudes and behaviors. 4. There were statistically significant effects of the exercise prescription program exposed to the experimental groups on the reduction of the resting heart rate and systolic blood pressure. 5. There were statistically significant effects of the exercise prescription program exposed to the experimental groups on the positive changes of their plasma TC / HDL-C ratio and triglycerides.