• Journal of the Korean housing association
• /
• v.16 no.4
• /
• pp.73-80
• /
• 2005

A high-rise residential building experienced stack effect problems during the winter such as difficulties in opening residential entrance doors and whistling noise from elevator doors generated by airflow. Field measurements were carried out on the building and the problems were verified by the analysis of the measurement results from three points of view: the total stack pressure difference, pressure distribution on each floor, and the location of the neutral pressure level. Based on the analysis of the three key parameters, possible solutions were proposed, such as zoning vertical shafts, lessening the airflow from the entrance doors on basement floors and lobby floor by installing vestibules, improving the airtightness of exterior walls, and installing separation doors where the problems occur. Simulations of proposed solutions were conducted and the effects of reducing the pressure difference were evaluated. Stack effect problems in a high-rise residential building were verified through field measurements and could be mitigated by the solutions which were drawn from the analysis of the field measurements and the simulation results.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.9 no.3
• /
• pp.187-194
• /
• 2013

Being in era of the digital economy, the impact of IT on our economy more and more increased. Along with this effect, IT becomes origin of predominance of competition in every category of industry. Regarding new trends in industry, companies have to mutate their IT skill set. Every industry has their color and environment of IT and uncertainty is different. For a company, it is most important to plan own strategy with strategy view on industrial environment. The idea of this study is to find the difference of Skill Requirement in every category of industry by find what are the most important jobs and skills of IT in every industry. We set skills by categorized curriculum of specialized IT education center, then with IT specialist, checked and retouched the results and surveyed with IT people in every industry on skill set and job of IT. The result of this study can gives the idea to who design curriculum and build educational contents that would fulfill the need of field. Also, this study would be meaningful that it opens the field of study of skill requirement in Korea.

• Journal of the Ergonomics Society of Korea
• /
• v.10 no.2
• /
• pp.31-42
• /
• 1991

To understand the shape of the neck in a view of garment planning, principal component analysis has been appliedto the measurement of the neck. The neck surface development and the cross sections of the neck have been observed. The materials consist of the body mearsurements, the neck surface developments and the cross sec- tions of the necks of a total of 108 korean woman students. The difference between the right side and the left side of the neck has not been reconginiged. But the differenece among the height of the front neck point, that of the side neck point and that of the back neck point has been recognized. 2. The initial 41 items have been found having variety and duplication. So two criteria have been made to solve those problems and the selection of 34 items have been made by each criterion. 3. 43 and 34 items have been compared by means of accumulative ratios of contribution and of clearness within the meaning of principal component. As a result, 34 measurement items have been further anylysis. 4. As a result of principal component analysis on the 34 items, the four principal components have been found obtaines and inter-preted. The four principal components are 1) the thick of the neck, 2) the front neck-line on the waist basic pattern, basic pattern, 3) the shape of the neck surface development, and 4) the back neck-line on the waist basic pattern. 5. According to the graphic informations concerning these principal components, the meaning of these four principal components has been grasped on the visual. As a result, there is a large individual difference in the shape of neck.

• The Journal of Advanced Prosthodontics
• /
• v.9 no.3
• /
• pp.208-216
• /
• 2017

PURPOSE. The aim of this study was to compare the precision of optical impression (Trios, 3Shape) versus that of conventional impression (Imprint IV, 3M-ESPE) with three different margins (shoulder, chamfer, and knife-edge) on Frasaco teeth. MATERIALS AND METHODS. The sample comprised of 60 zirconia half-crowns, divided into six groups according to the type of impression and margin. Scanning electron microscopy enabled us to analyze the gap between the zirconia crowns and the Frasaco teeth, using ImageJ software, based on eight reproducible and standardized measuring points. RESULTS. No statistically significant difference was found between conventional impressions and optical impressions, except for two of the eight points. A statistically significant difference was observed between the three margin types; the chamfer and knife-edge finishing lines appeared to offer better adaptation results than the shoulder margin. CONCLUSION. Zirconia crowns created from optical impression and those created from conventional impression present similar adaptation. While offering identical results, the former have many advantages. In view of our findings, we believe the chamfer margin should be favored.

• Journal of the Korean Home Economics Association
• /
• v.35 no.4
• /
• pp.79-94
• /
• 1997

This study was performed to develop a basic stacks pattern for middle-aged women reflecting the characteristics of their lower body types. Anthropometric measurements using sliding guage method were carried out for 4 women 40's For the analysis of the lower body types horizontal and vertical section maps obtained by sliding gauge method and 2 indices were produced. Based on the slacks construction components produced by the drafts of their lower body surface experimental slacks pattern was designed. Multiple comparison test was used to compare 3 existing slacks patterns with the experimental pattern. 1. The results of the body section map analysis were as follows: 1) In the frontal view silhouette of vertical section maps there were less individual differences in items with skeleton landmarks than those without them. 2) In the shape of horizontal section maps waist section represented more round shape than the others and thigh maximum width section had the flattest shape. Flat ratios(depth/width) of subjects were much higer than those of young women which clarified the change of depth was bigger than that of width with aging process. 2. The slacks construction components for pattern drafting were as follows: 1)Ease amount of waist was 0.5cm and front and back waist girth difference was 1.2cm Ease amount of hip was 1,8cm and front and back hip girth difference was 0.7 cm 2) The amount of dart intake incresed in the order of side(4cm) back(3,6cm) from (2.8cm) The length of dart leg incresed in the order of front side back.

• Journal of the Society of Naval Architects of Korea
• /
• v.42 no.4 s.142
• /
• pp.315-321
• /
• 2005

The effect of water depth on the wave making resistance performance is great where Froude number based on the water depth is close to one. The increase of wave making resistance due to the shallow water effect is evaluated by a numerical analysis in the present study. Three-dimensional Navier-Stokes and continuity equations are employed for the present study and the equations are discretized by finite difference method. The interface between water and air is determined by the level set method. In order to validate the numerical method, the change of resistance performance for Wigley hull according to the water depth is evaluated and the computed resistance coefficient is compared with measured one. The present numerical method is applied for the simulation of wave phenomena around a Ro-Pax hull form and the computed results are discussed in the resistance performance point of view.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.24 no.1
• /
• pp.313-324
• /
• 1997

The aim of the present study was to describe an safe and convenient method for the early detection of enamel caries using laser fluorescence. Fluorescence from natually carious lesion of human teeth illuminated by an argon laser(488nm) was observed and photographed using barrier filter. Intact enamel was found to fluorescence with a yellowish light. Whereas, incipient caries lesions in the enamel were dearly visible as dark areas in contrast to the fluorescence surroundings. For evaluation of accuracy of this method, lesion depth measured by the laser fluorescence in light microscope was compared with that polarizing microscope. The results from the present study can be summarized as follows : 1. Enamel caries of smooth surface was observed as pale white spot and undefined outline in ordinary light. Whereas, lesion was clearly visible as dark spot in laser fluorescence. 2. There was no difference between ordinary light view and laser fluorescence in occlusal surface and interproximal surface. 3. There was no significant difference between the lesion depth observed by laser fluorescence with light microscope and polarizing microscope. Apparent correlation exists between two groups.

• Journal of Technologic Dentistry
• /
• v.17 no.1
• /
• pp.10-25
• /
• 1995

The purpose of this study is to get the difference of the castability in the production of partial denture between Precious Metal Alloys and Base Metal Alloys accompanied with the frequency of reuse. As materials for an experiment, we selected Baker-444 and Soo-444 and Soo-sung as Precious Metal Alloys, New Crown and Chrome Cobalt as Base Metal Alloys. And we tired to case all of them seven times. The experimental results were as follows : 1) In the probability of segments, Baker-444 showed 100$\pm$0.00%, Soo-sung 97.24$\pm$1.58%, New Crown 95.63$\pm$4.28%, and Chrome Cobalt 91.03$\pm$7.76%. Consequently, Precious Metal Alloys were decidely superior to Base Metal Alloys in the castability. 2) In the view of the acheived result, burn-out temperature and smocking time had greatly affected the castability. 3) After casting, Precious Metal Alloys were much less than Base Metal Alloys in the quantity of consumption. It made much difference from the the compiled stastics(p<0.01)

• Journal of Korean Elementary Science Education
• /
• v.28 no.1
• /
• pp.46-54
• /
• 2009

The purpose of this study was to examine the perception of students about pseudo-science in consideration to their personality traits, cognitive style, and awareness of the nature of science, which might all have a great impact on their behavior and thinking. The subjects of this study were 129 sixth-grade school children in a small urban community in Gyeonggi province. The way they looked at pseudo-science was investigated after three kinds of traits were selected as variables, including personality traits, cognitive style, and awareness of the nature of science. Four different instruments were utilized, which respectively covered personality traits, cognitive style, awareness of the nature of science and perception of pseudo-science. The results of the study were as follows: First, the children with higher emotional stability and liveliness showed higher permeability towards pseudo-science, while made no significant difference on their view of pseudo-science. Second, their cognitive style made no significant difference to their outlook on pseudo-science. Third, as for link between awareness of the nature of science and pseudo-science, the students with a poor understanding of the nature of science were significantly different from those who had a better understanding of it in perception of pseudo-science(p<.05).

• ETRI Journal
• /
• v.33 no.1
• /
• pp.99-109
• /
• 2011

This paper concerns a robust real-time voice activity detection (VAD) approach which is easy to understand and implement. The proposed approach employs several short-term speech/nonspeech discriminating features in a voting paradigm to achieve a reliable performance in different environments. This paper mainly focuses on the performance improvement of a recently proposed approach which uses spectral peak valley difference (SPVD) as a feature for silence detection. The main issue of this paper is to apply a set of features with SPVD to improve the VAD robustness. The proposed approach uses a weighted voting scheme in order to take the discriminative power of the employed feature set into account. The experiments show that the proposed approach is more robust than the baseline approach from different points of view, including channel distortion and threshold selection. The proposed approach is also compared with some other VAD techniques for better confirmation of its achievements. Using the proposed weighted voting approach, the average VAD performance is increased to 89.29% for 5 different noise types and 8 SNR levels. The resulting performance is 13.79% higher than the approach based only on SPVD and even 2.25% higher than the not-weighted voting scheme.