• Journal of the Korean Society of Clothing and Textiles
• /
• v.36 no.6
• /
• pp.583-591
• /
• 2012

This study selected three model designs used for air injection type welding clothes designed for insulation purposes and analyzed the performance of each design. The bending characteristics were analyzed in order to identify the flexibility of the welded areas; subsequently, the seam breaking strength and water pressure resistance were analyzed to identify the bonding strength. In addition, two types of waterproof fabric, polyurethane (PU) coated 2 layer and PU laminated 2 layer fabrics, were used for a performance analysis, according to fabric processing specifications. The circle type showed the highest flexibility in the terms of bending characteristics that influence wearability and were followed by the wave and the straight type. In terms of breaking strength, the straight type showed the highest breaking strength, followed by the wave and the circle type. The water pressure resistance analysis found that the wave type was superior to the straight type in terms of water pressure resistance. The wave type is deemed to be a design type suitable for maximizing performance, provided that the issue of stabilization in the welding production process is addressed. Looking at the bending characteristics of waterproof fabric for each specification, the laminating waterproof cloth outperformed the coated waterproof cloth in terms of flexibility. However, in terms of seam breaking strength, the coated waterproof cloth outperformed the laminated cloth. In contrast, the water pressure resistance of the laminated waterproof fabric was found to be higher than the coated waterproof fabric, leading to the conclusion that the bonding strength of the laminated waterproof fabric is higher than that of the coated waterproof fabric based on the assumption of injecting air.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.23 no.5
• /
• pp.1-14
• /
• 2020

In order to improve the urban thermal environment, efforts are being made to increase green areas in cities that include park construction, planting, and green roofing. Among these efforts, urban parks play an important role not only in improving the urban thermal environment, but also in terms of ecosystem services (serving as resting places for citizens, providing cleaner air quality, reducing noise, etc.). Therefore, the purpose of this study is to suggest planning and management guidelines for urban parks that are effective in improving the thermal environment, by analyzing the urban surface temperature reduction performance of urban parks. To do this, first, land surface temperature was calculated by using Landsat 8 images. Second, the PCI (Park Cool Island) index was calculated to identify the temperature reduction performance of urban parks. Third, the characteristics of parks (area, shape, vegetation) and the surrounding spatial characteristics (land cover, building-related variables, etc.) were identified. Finally, the relationship between the PCI indices (PCI scale, PCI effect, PCI intensity) and the characteristics of the parks and their surroundings were analyzed. The results revealed that the parks consisting of a larger area, simple shape, and higher tree coverage ratio had increased PCI performance, and were advantageous for improving the urban thermal environment. Meanwhile, PCI performance was found to have decreased in areas with a higher impermeable area ratio and building coverage ratio. The outcomes of this study can be used to identify priority areas for planning and management of urban parks and can also be utilized as planning and management guidelines for improving urban thermal environment.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.38 no.4
• /
• pp.505-516
• /
• 2018

In order to establish an efficient bridge maintenance strategy, the future performance of a bridge must be estimated by considering the current performance, which allows more rational way of decision-making in the prediction model with higher accuracy. However, personnel-based existing maintenance may result in enormous maintenance costs since it is difficult for a bridge administrator to estimate the bridge performance exactly at a targeting management level, thereby disrupting a rational decision making for bridge maintenance. Therefore, in this work, we developed a representative performance prediction model for each bridge element considering uncertainty using domestic bridge inspection data, and proposed a bayesian updating method that can apply the developed model to actual maintenance bridge with higher accuracy. Also, the feasibility analysis based on calculation of maintenance cost for monitoring maintenance scenario case is performed to propose advantages of the Bayesian-updating-driven preventive maintenance in terms of the cost efficiency in contrast to the conventional periodic maintenance.

• Korean Journal of Poultry Science
• /
• v.27 no.1
• /
• pp.19-23
• /
• 2000

The effects of microbial phutase on laying performance and phosphorus utilization were examined at different levels of dietary nonphosphorus(NPP) in 320 23-week-old Hy-line brown hens for 12weeks. Diets were formulated 0.275%(T1), 0.220%(T2), 0.165%(T3) of NPP levels, and supplemental microbial phytase was 300DPU/kg diet constantly. Conventional diet(C) was formulated 0.275% NPP level without microbial phytase. Egg production and egg mass were higher in T2 than the others (p<0.05), and average egg weight was higher in T1 than the other (p<0.05). Egg productivity was tended to increase with supplemental phytase compared to conventional diet. Daily feed intake a hen also increased in T2 (p<0.05). Feed conversion ratio was improved slightly without significant difference. Eggshell breaking strength and thickness were not different significantly among the treatments. Haugh unit and yolk color were also not different. Calcium and phosphorus retention in body increased in T2 (p<0.05), but dry matter and nitrogen retention were not different significantly. Differences in nitrogen and calcium excretions were not found among the treatments. But phosphorus excretion decreased in order of dietary phosphorus levels with supplement phytase compared to C (p<0.05). Tibial ash, calcium and phosphorus were similar among the treatments. In conclusion, supplemental microbial phytase in laying diet may help to utilize phytase phosphorus, and could decrease NPP intake.

• Research in Community and Public Health Nursing
• /
• v.8 no.2
• /
• pp.368-380
• /
• 1997

This descriptive comparative study was conducted to compare the relationships among self-esteem, self-efficacy, perceived health status and the performance of health promoting lifestyles for nursing and non-nursing students. The sample consisted of 246 nursing students and 166 non-nursing students at an evening class of junior college in T city. The data was collected by a self reporting questionnaire from March 2 to March 17, 1997 and analyzed by SPSS Win. 7.0 program for frequency, mean, percentage, t -test, ANOVA, and a Pearson correlation coefficient. The results of this study are summarized as follows: 1. The results of the comparison between the two groups was not significantly different for self esteem and perceived health status, but significantly different for self-efficacy. Nursing students had higher scores on self -efficacy than non-nursing students(t=4.621. p<.05). 2. There was a statistically significant difference between the two groups concerning a health promoting lifestyle. Nursing students ($157.73{\pm}20.26$) had higher scores on total health promotion as well as its 8 subscales than non -nursing students ($048.15{\pm}21.51$,), (t=21.074, p<.001). On subscales, nursing students had the highest score in sanitary life(3.22) and the lowest score in professional health maintenance(1.54). Non -nursing students had the highest score in harmonious relationships(3.10) and the lowest score in professional health maintenance (1.48). 3. Performance in a health promoting lifestyle was significantly correlated with such demographic variables as age and grade for nursing students, and types of dwelling for non -nursing students. 4. Perceptions of good health have been positively correlated with health promoting lifestyles. Those persons who rated their health as good showed the highest score, followed by excellent ,average, poor in that order. 5. Performance in health promoting lifestyles was significantly correlated with self-esteem, self-efficacy and, perceived health status. The most important factor that affect performance in health promoting lifestyles was self -efficacy.

• Journal of Industrial Convergence
• /
• v.21 no.1
• /
• pp.95-102
• /
• 2023

This study was to identify the factors affecting nurses' use intention of digital healthcare and the moderating effect of clinical career based on the UTAUT model. The items were composed by performance expectancy 3 items, facilitation condition 3tiems, and perceived risk 3 items. CFA was performed to verify the construct validity. As a results, average variance extracted (AVE) was .5 or higher, and construct reliability (CR) was .7 or higher. Model fit was confirmed as CMIN/df=1.797, GFI=.955, CFI=.979, TLI=.968, IFI=.979, and RMSEA=.063. The internal reliability was .93 for performance expectancy, .84 for facilitating conditions, and .64 for perceived risk. Performance expectancy, facilitating condition, and perceived risk had a significant effect on use intention, and clinical career showed a moderating effect(t=-2.159, p=.032). Therefore, in order to enhance the use intention of digital health care, performance expectancy, and facilitating conditions should be raised and perceived risk should be reduced.

• KIPS Transactions on Computer and Communication Systems
• /
• v.7 no.7
• /
• pp.165-174
• /
• 2018

The purpose of this study is to verify the effects of R&D process maturity on product development performance and to verify whether R&D project performance mediating effect. The questionnaire was collected and analyzed to 131 persons related to the R&D work in 55 companies and public institutions performing R&D work. The results of this study are as follows, the effect of R&D process maturity on product development performance and mediating effect of R&D project performance were analyzed by simple and multiple regression analysis. Regression analysis was analyzed by SPSS statistical program. The higher the maturity level of the R&D process, the higher the product development performance and the R&D project performance, and the R&D project performance is partially mediated. It is concluded that it is important to establish and operate a systematic R&D process and to develop a project management methodology suitable for the characteristics of a company in order to improve product development performance. It is expected that if this study are utilized as practical R&D management methodology in corporate management, it will contribute to improvement of company product performance.

• ETRI Journal
• /
• v.22 no.2
• /
• pp.32-42
• /
• 2000

The existing multi-dimensional index structures are not adequate for indexing higher-dimensional data sets. Although conceptually they can be extended to higher dimensionalities, they usually require time and space that grow exponentially with the dimensionality. In this paper, we analyze the existing index structures and derive some requirements of an index structure for content-based image retrieval. We also propose a new structure, for indexing large amount of point data in a high-dimensional space that satisfies the requirements. in order to justify the performance of the proposed structure, we compare the proposed structure with the existing index structures in various environments. We show, through experiments, that our proposed structure outperforms the existing structures in terms of retrieval time and storage overhead.

• Journal of Environmental Health Sciences
• /
• v.27 no.3
• /
• pp.27-34
• /
• 2001

This paper discussed the shape effect of ceramic support carrier in order to facilitate biomass immobilization. The shape of ceramic support carrier was modified hollow pipe type into hollow gear type. After seeding, microorganisms were attached in crevices where protection from shear forces or surfaces where easy to contact with support carrier surface. In case of hollow gear type carrier, initial attachment rate was faster than that of hollow pipe type and obtained thick biofilm. Synthetic wastewater(COD:75~880 mg/L, organic loading rate:0.36~4.22 kgCOD/㎥.d) was treated aerobic fixed bed biofilm reactor where 100% of the volume was filled with the ceramic carrier. COD removal efficiency of reactor filled with gear type support carrier was a little high withing 70 days, and then showed similar removal efficiency. It was found that highly loaded operation with up to 4.22 kgCOD/㎥.d was possible in both reactor. Total biomass amounts of pipe type was higher than gear type, however, attached biomass of gear type was higher than that of pipe type.

• Journal of Mechanical Science and Technology
• /
• v.16 no.9
• /
• pp.1175-1182
• /
• 2002

The commercial viability of heat exchanger is mainly dependent on its long-term fouling characteristic because the fouling increases the pressure loss and degrades the thermal performance of a heat exchanger. An experimental study was performed to investigate the characteristics of fluid flow and heat transfer in a fluidized bed heat exchanger with circulating various solid particles. The present work showed that the higher densities of particles had higher drag force coefficients, and the increases in heat transfer were in the order of sand, copper, steel, aluminum, and glass below Reynolds number of 5,000.