• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.5
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• pp.381-387
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• 2017

Fiber-reinforced composites not only have a direction of thermal expansion coefficient, but also inevitably suffer thermal stress effects due to the difference between the manufacturing process temperature and the actual use temperature. The damage caused by thermal stress is more prominent in the case of thick composite laminates, which are increasingly applied in the aerospace industry, and have a great influence on the mechanical function and fracture strength of the laminates. In this study, the dimensional reduction and thermal stress recovery theory of composite beam structure having high slenderness ratio is introduced and show the efficiency and accuracy of the thermal stress comparison results between the 3-D finite element model and the dimension reduction beam model. Efficient recovery analysis study will be introduced by reconstructing the thermal stress of the composite beam section applied to the thermal environment by constructing the dimensional reduction modeling and recovery relations.

• Journal of the Korea Society of Computer and Information
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• v.15 no.4
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• pp.107-118
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• 2010

The user interface is the medium, which provides the users to have an access to the web-based information system. The user interface is the means of improving usability and accessibility for the user, as well as being the core component in the web-based information system. In this paper, the audit framework of the user interface was developed to upgrade the usability and accessibility; it was based on the three basic components of the current audit framework in the web-based information system. At the time of an audit, the UI process of the 'Analysis', 'UI Design', 'UI Production', and 'Test' was defined, which was analyzed through the web development methodology. Also, for the area of an audit, the 'Information', 'Design', and 'Technology' were defined by the analysis of the components that makes up the user interface, From the view of an audit, the standard criteria of an assessment were set as 'Usability', 'Accessibility', and 'Cross Browsing'. Through the framework that was proposed in this paper, practical audit applies the performed examples. By this, the efficiency of the proposed framework was verified.

• Korean Journal of Veterinary Research
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• v.30 no.2
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• pp.171-175
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• 1990

Radioimmunoassay for progesterone in Korean native cows was developed using the anti-4-pregnen-$11{\alpha}$-ol-3,20-dione-hemisuccinate bovine serum albumin as an antibody. The final dilution of antibody was 1 : 5,000. The percentage recoveries of [$^3H$] progesterone was $83.5{\pm}1.6$. The sensitivity of the assay was 8 pg per ml. The intra- and interassay coefficients of variation for the quality controls were 6.2 and 10.4%, respectively. This radioimmunoassay can be applied to puberty, estrus dectection, pregnancy diagnosis, postpartum period and diagnosis of reproductive disorders in domestic animals.

• Environmental and Resource Economics Review
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• v.19 no.3
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• pp.689-711
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• 2010

This study attempts to find the relationship between achievement of environmental industry and development of financial sector by analyzing cross-sectional data for OECD countries. Development of financial industry has a positive effect on environmental industry. Green financing also affects improvement of environmental quality. Demand for environmental quality is positively influenced by GDP per capita, while financial crisis has a bad effect on environmental performance. Government-led green financing in Korea has a major role in the Korean environmental policy for years. While market-oriented green financing improves the efficiency of regulation, government-led green financing may delay internalization of environmental cost due to its subsidizing effect. Further study should include systematic analysis on the scope of green financing and its qualitative attribute and fundamental causality between green financing and environmental improvement.

• The KSFM Journal of Fluid Machinery
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• v.20 no.1
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• pp.65-73
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• 2017

Intercoolers for multi-stage turbocharger of the hydrogen reciprocating engine for HALE UAV are installed for reducing the charged air inlet temperature of the engine. The intercooler is air to air, cross flow, plate-fin type and the fin configuration is offset-strip fin which is referenced from the heat exchanger of the ERAST. Most of HALE UAV's cruising altitude is 60,000 ft and the density of air for this altitude is very low compared to sea level. Therefore the required heat transfer area for the HALE UAV is about three-times bigger than the sea level. Consequently, it is essential to design to meet the required efficiency of intercooler in the range of not excessively growing the weight of the heat exchanger. The quasi-one dimensional heat transfer design/analysis for satisfying the requirement of the engine are written in this paper. The numerical analyses for estimating the coolant flow rate of the engine bay and pressure loss in the header and core are also summarized.

• Journal of Korean Society for Geospatial Information Science
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• v.3 no.2 s.6
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• pp.29-42
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• 1995

Route design in topographical plane map brings many problems in efficiency and requires much time and labor by hand Recently, the active studies of efficient route design method using 3-D terrain information are being developed according to increasing concentration on GSIS. In order to analyze terrain information for route design efficiently, this study presents objective and overall datum by applying SQL in construction and analysis of database and the possibility of three-dimensional terrain information analysis, This study generates 3-D base map on topographical map of scale 1:5,000 and acquires terrain information that have various thematic map data; contour, land use, roadway, and drange. This is a study on the application of SQL in route design and construction of the terrain information that linked by graphic datum of completed topographical map and attributed datum of database. As the result of this study, we can produce promptly and efficiently design datum of profile annotation, cross section, and volume computations to the preliminary route for route design and apply this efficient method to route design by understanding visual DTM which is composed of the roadway and the natural scene after design.

• Journal of the Korean Vacuum Society
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• v.5 no.4
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• pp.348-353
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• 1996

Rapid thermal annealing (RTA) was applied to polycrystalline CdTe thin films evaporated on CdS/ITO/glass substrate and the effect of the annealing temperatures and the atmosphere on physical properties of polycrystalline CdTe thin films and CdTe/CdS solar cell characteristics were studied. Results obtained by EDX showed that the bulk composition of CdTe remained stoichiometric after annealing at $550^{\circ}C$ in the air but the surface composition became Cd-rich. Cross-sectional TEM and micro EDX showed that columnar grains and micro-twins remained even after RTA, however, and the sulfur content in the annealed CdTe (added by sulfur diffusion from CdS during the annealing) was much smaller than that by furnace annealing. Among the investigated RTA temperatures and gas environments, the cell made with CdTe annealed at $550^{\circ}C$ in air showed the best solar energy conversion efficiency.

• Journal of the Korea Concrete Institute
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• v.23 no.6
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• pp.781-790
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• 2011

This paper contains the experimental results on strengthening effect of RC beams strengthened with NSM CFRP reinforcement and various strengthening details. A total of 14 beams have been tested to analyze strengthening effects of NSMR with various reinforcement details. Variables were cross-sectional shape of CFRP reinforcements, strengthening areas, grooves the number and location etc. Test results revealed that failure modes of NSMR showed two types. One was bond failure at interface between concrete and filler and the other was CFRP rupture. Also, failure mode of specimens with two grooves occurred premature bond failure because of superposition of failure surfaces at concrete around grooves. failure mode of MI specimens considered the equivalent section have changed bond failure to CFRP rupture and CFRP efficiency has improved 83% to 100%.

• Journal of Korean Academy of Nursing
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• v.29 no.1
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• pp.48-60
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• 1999

This study was done to determine the factors influencing smoking-cessation behavior in female university students. A total of 534 students participated in this cross sectional study by answering a questionnaire. The data collection was done between September 1 and October 31, 1997 The measurement tools used in this study were the self help change process scale (Cronbach's alpha＝.9930 : developed by Oh & Kim, 1996) for smoking-cessation behaviors, the self efficacy scale(Cronbach's alpha＝.8250 : developed by Sherer et al, 1982), the sex role acceptance scale (KR－20＝.7757 : developed by Kim, 1991) and the social support scale(Cronbach's alpha＝.9172 : developed by Park, 1985). The summarized results are follows : 1. The mean scores for smoking-cessation behaviors in smokers (N＝150) was 91.72 that was considered a middle score compared to the total possible score of measurement tool (150.0). The mean score for smoking-cessation behaviors by smoking-cessation step showed significant different between the groups(F＝11.71, p＝.000). 2. The group with no experience in smoking(N＝332) showed a high general self efficacy score (t＝5.24, p＝.000), and more openness to sex role acceptance(t＝-2.15, p＝.032) compared to the group with smoking experience (N＝202). 3. General self efficacy, sex role acceptance, and social support were not different significantly between the groups according to the steps in smoking-cessation. 4. Significant factors influencing smoking-cessation behavior (total, sub concepts) were religion, sex role acceptance, social support, smoking duration, smoking attitude, time of smoking onset, amount of smoking, drinking, and perception of health status. 5. Smoking-cessation behaviors which explained 11% of the variance were smoking attitude, and smoking duration. In conclusion, this study identified factors influencing smoking-cessation behavior. Thereby it will help in the development of smoking-cessation intervention strategies. For future research, exploration other determinants of smoking cessation behaviors, evaluation of intervention efficiency, and comparative study by gender characteristics are needed.

• Journal of Environmental Health Sciences
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• v.35 no.6
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• pp.500-509
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• 2009

Passive samplers have been used for many years for the sampling of organic vapors in work environment atmospheres. Currently, all passive samplers used in domestic occupational monitoring are foreign products. This study was performed to evaluate variable parameters for the development of passive organic samplers, which include the geometry of the device and diffusive length for the sampler design. Four prototype diffusive lengths; A-1(4.5 mm), A-2(7.0 mm), A-3(9.5 mm), A-4(12.0 mm) were tested for adsorption performances to a chemical mixture (benzene, toluene, trichloroethylene, and n-hexane) according to the US-OSHA's evaluation protocol. A dynamic vapor exposure chamber developed and verified by related research was used for this study. The results of study are as follows. The results in terms of sampling rate and recommended sampling time test indicate that the most suitable model was A-3 (9.5 mm diffusive lengths on both sides) for passive sampler design in time weighted average (TWA) assessment. Sampling rates of this A-3 model were 45.8, 41.5, 41.4, and 40.3 ml/min for benzene, toluene, trichloroethylene, and n-hexane, respectively. The A-3 models were tested on reverse diffusion and conditions of low humidity air (35% RH) and low concentrations (0.2 times of TLV). These conditions had no affect on the diffusion capacity of samplers. In conclusion, the most suitable design parameters of passive sampler are: 1) Geometry and structure - 25 mm diameter and 490 $mm^2$ cross sectional area of diffusion face with cylindrical form of two-sided opposite diffusion direction; 2) Diffusive length - 9.5 mm in both faces; 3) Amount of adsorbent - 300 mg of coconut shell charcoal; 4) Wind screen - using nylon net filters (11 ${\mu}m$ pore size).