• Title/Summary/Keyword: Internal and External Characteristics

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Wind pressure characteristics of a low-rise building with various openings on a roof corner

  • Wang, Yunjie;Li, Q.S.
    • Wind and Structures
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    • v.21 no.1
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    • pp.1-23
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    • 2015
  • Wind tunnel testing of a low-rise building with openings (holes) of different sizes and shapes on a roof corner is conducted to measure the internal and external pressures from the building model. Detailed analysis of the testing data is carried out to investigate the characteristics of the internal and external pressures of the building with different openings' configurations. Superimposition of the internal and external pressures makes the emergence of positive net pressures on the roof. The internal pressures demonstrate an overall uniform distribution. The probability density function (PDF) of the internal pressures is close to the Gaussian distribution. Compared with the PDF of the external pressures, the non-Gaussian characteristics of the net pressures weakened. The internal pressures exhibit strong correlation in frequency domain. There appear two humps in the spectra of the internal pressures, which correspond to the Helmholtz frequency and vortex shedding frequency, respectively. But, the peak for the vortex shedding frequency is offset for the net pressures. Furthermore, the internal pressure characteristics indirectly reflect that the length of the front edge enhances the development of the conical vortices.The objective of this study aims to further understanding of the characteristics of internal, external and net pressures for low-rise buildings in an effort to reduce wind damages to residential buildings.

A Study on the Relationship between Temperament and Mathematics Academic Achievement

  • Li, Mingzhen;Pang, Kun
    • Research in Mathematical Education
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    • v.11 no.3
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    • pp.197-207
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    • 2007
  • Based on a survey on 1620 students in primary school and secondary school., by adopting Eysenck Personality Questionnaire (EPQ), we got the following findings : 1. There is close relationship between emotionality characteristics of temperament and mathematics academic achievement of the subjects at Grade 5 (Primary 5), Grade 8 (Junior Secondary 2), and Grade 10 (Senior Secondary 2). Also there is close relationship between internal-external directivity characteristics of temperament and mathematics academic achievement at Grade 5 and Grade 8. While there is not close relationship between internal-external directivity characteristics of temperament and mathematics academic achievement at Grade 10; 2. There is close relationship between temperament types and mathematics academic achievement of the subjects from the three grades. Superior temperament, which benefit learning mathematics, are sanguine, sanguine-phlegmatic and phlegmatic; While inferior temperament types, which don't benefit learning mathematics, are choleric, melancholic and choleric-melancholic. With the rising of grade, temperament types of benefiting learning mathematics converts from external directivity emotion balance to balance of internal-external directivity emotion stability. While temperament of no benefiting learning mathematics converts from internal directivity emotion balance to balance of internal-external directivity emotion instability; 3. In mathematics education, students' temperament difference, which affects learning mathematics, should be recognized. Mathematics teachers should find out the best teaching ways, forms and methods which are suitable for student's temperament type, so that the students with different temperament types can gain better mathematics academic achievement.

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An Empirical Study on the Determinants of Intention to Use B2B e-Marketplace

  • An, Youngsin;Yang, Haesool
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.9
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    • pp.155-161
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    • 2017
  • As the e-marketplace becomes the core of management activities, researches on motivation, transaction type, strategy, satisfaction, risk management, performance evaluation, etc. have been actively studied, but the factors influencing actual utilization have not been fully. Especially, the factors that affect the intention of the users are limited without consideration of internal environment, external environment, e-marketplace characteristics such as operating rules, characteristics of the company to be used. In order to derive the determinants of B2B e-marketplace use, this study was conducted to examine the relationship between internal environment, external environment, e-marketplace characteristics as independent variables, intention of use as dependent variable, participation qualification, The results were as follows. First, the previous study limited the determinants of intention to use to either internal or external, but this study presented an integrated model that considers both factors. Second, the characteristics of companies participating in e-marketplace were identified by using participation qualification and activity scope as control variables.

Aesthetic Characteristics of Traditional Wedding Dress in Japan (일본 여자 전통 혼례복식의 미적 특성)

  • 양현주;조윤주;권영숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.26 no.7
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    • pp.993-1004
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    • 2002
  • This study was designed to examine the aesthetic characteristics of traditional wedding dress in Japan based on the internal$.$external aesthetics. They were extruded external and internal aesthetics based on pattern, color and fitting. The results of this study can be summarized as follows; Decorative characteristics in external aesthetics extracted into three factors; fantasticism, movement, amusement. The fantasticism was based on the omitted pattern, painting gold. The movement was presented through irregular composition, fitting method, and silhouette. The amusement was expressed through the composition focus on a near view and pattern reminded of bring up the image. Fitting characteristics in external aesthetics extracted into four factors; grace, cubic effect, optical illusion, and tradition. The pace was expressed through the weight, formativeness, and layered look The cubic effect was presented through spacing of belt and H-line silhouette. The optical illusion was based on the straight line of seam, V-pleats and straight silhouette of fitting, and high-waisted belt. The tradition expressed through the unchanged form since Heian-dynasty. Internal aesthetics were characterized by the naturalism and the moderation. The naturalism was presented through the natural pattern which based on subjective feeling, indignity and position of wearing man, and color based on taste. The necessaries, or pressed artificial moderation, were expressed through the clothing silhouette by simplicity.

Classification and Characteristics of Augmented Reality Contents of Fashion Brands (패션 브랜드의 증강현실(AR) 콘텐츠 유형 및 특성)

  • Lee, Hyun-Jin;Ku, Yang-Suk
    • Fashion & Textile Research Journal
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    • v.22 no.3
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    • pp.310-322
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    • 2020
  • This study investigated the classification and characteristics of augmented reality (AR) content of fashion brands. The AR contents of fashion brands were classified according to user participation space and content delivery method. Based on these types, eight case studies were conducted, along with a discussion of AR characteristics in terms of presence, interactivity, and immersion. The results showed that AR content could be divided into four types: offline visit-external information type, offline visit-internal experience type, online utilization-external information type, and online utilization-internal experience type. It was also found that there were differences in characteristics for each type of AR content. First, the offline visit-external information type requires various new content that can provide entertainment immersion to users. Second, the offline visit-internal experience type requires a powerful inducement for users to visit a specific space providing AR content and to participate in augmented environments. Third, the online utilization-external information type needs a series of AR content that can consistently incite users' curiosity about brands and products. Fourth, the online utilization-internal experience type needs effective content to improve users' shopping experience with the virtual fitting of fashion accessories, such as eyewear, hats, jewelry, and watches. Accordingly, fashion companies should create contents that can provide appropriate presence, interactivity, and immersion by AR type.

Internal and External Characteristics of Information Security Officers Affecting Organization's Information Security Performance (조직 정보보호성과에 영향을 미치는 정보보호담당임원의 내·외적 특성)

  • Oh, Ha-Kyeong;Kim, Tae-Sung
    • Journal of Information Technology Applications and Management
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    • v.27 no.4
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    • pp.1-19
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    • 2020
  • Infringement of information security has caused the corporate image to be damaged and share price to fall, and it is emerging as an organizational risk. The value of information assets in enterprises has led to a higher level of security than in the past. As a result, companies are aware of the need for officers to protect information and to oversee a security management system. However, despite the growing importance of information security officers, there is a lack of research on their roles and characteristics. This study validates the relationship between determinants that affect the performance of information security. And a structural equation model was presented and empirically analyzed to see the impact of the internal and external characteristics of the staff in charge of information security on the organization's information security performance.

Stability Analysis of an Asymmetric Shaft with Internal Damping (내부감쇠가 있는 축비대칭 구동축의 안정성 해석)

  • Shin, Eung-Soo
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.22 no.1
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    • pp.8-14
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    • 2013
  • This paper intends to provide the whirling characteristics of an asymmetric rotor-shaft system with a non-ideal DC motor. The equations of motion have been derived in terms of system parameters such as the internal/external damping, the asymmetry and the motor voltage. By imposing the conditions that the motor input power should be balanced by the dissipated power, steadystate whirling characteristics are obtained such as the whirling amplitude, the whirling frequency and the stability diagrams. Results show that the whirling stability is affected by the internal/external damping and the asymmetry as well as the motor voltage. Also, the whirling amplitude at the steadystate is increased and the motor speed is lowered as the internal damping becomes higher or the external damping is reduced. In addition, the asymmetry causes the variation of the whirling orbit, which becomes splitted into two distinct trajectories. Finally, non-ideal characteristics of the DC motor is found to reduce the whirling motion in case of steadystate whirling with high asymmetry and high internal damping.

Effect of building volume and opening size on fluctuating internal pressures

  • Ginger, John D.;Holmes, John D.;Kopp, Gregory A.
    • Wind and Structures
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    • v.11 no.5
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    • pp.361-376
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    • 2008
  • This paper considers internal pressure fluctuations for a range of building volumes and dominant wall opening areas. The study recognizes that the air flow in and out of the dominant opening in the envelope generates Helmholtz resonance, which can amplify the internal pressure fluctuations compared to the external pressure, at the opening. Numerical methods were used to estimate fluctuating standard deviation and peak (i.e. design) internal pressures from full-scale measured external pressures. The ratios of standard deviation and peak internal pressures to the external pressures at a dominant windward wall opening of area, AW are presented in terms of the non-dimensional opening size to volume parameter, $S^*=(a_s/\bar{U}_h)^2(A_W^{3/2}/V_{Ie})$ where $a_s$ is the speed of sound, $\bar{U}_h$ is the mean wind speed at the top of the building and $V_{Ie}$ is the effective internal volume. The standard deviation of internal pressure exceeds the external pressures at the opening, for $S^*$ greater than about 0.75, showing increasing amplification with increasing $S^*$. The peak internal pressure can be expected to exceed the peak external pressure at the opening by 10% to 50%, for $S^*$ greater than about 5. A dominant leeward wall opening also produces similar fluctuating internal pressure characteristics.

Analysis of the Energy Saving Effect for the External Insulation Construction by Building Load Calculation Method (건물 부하계산 프로그램을 이용한 외단열 시공의 에너지 절감 효과 분석)

  • Park, Jaejoong;Myeong, Jemin;Song, Doosam
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.29 no.3
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    • pp.97-104
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    • 2017
  • Reinforcement of insulation in apartment buildings reduces the heating and cooling energy consumption by lowering the heat transfer in the building envelope. There are differences between internal and external insulation methods in heat transmission properties. However, some building load calculation programs cannot analysis the differences between the two. This is because these programs do no account for the timelag or thermal storage effect of the wall according to the location of insulation. In this study, the heat transmission characteristics of internal and external insulation were analyzed by EnergyPlus, and heating and cooling energy demand was compared. The results showed that external insulation system had lower heating and cooling loads than internal insulation system. Also the heat transfer rate of external insulation is steadier than internal insulation. About 13.6% of heating and cooling energy demand decreased when the outdoor wall was finished with external insulation compared to the demand with internal insulation.

Influence of external structure and internal stacking on wind load characteristics of large-span spherical shell structure

  • Xiaobing Liu;Anjie Chen;Qun Yang;Bin Feng;Xuedong Tian
    • Wind and Structures
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    • v.39 no.3
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    • pp.191-205
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    • 2024
  • To investigate the wind load characteristics of a large-span spherical shell structure, a rigid model pressure test was conducted in a wind tunnel laboratory. The study aimed to examine the impact of various external structures and internal stacking forms on the wind loads of a spherical shell structure in a practical engineering project. This project features two adjacent spherical structures, each spanning 130 m and standing 67 m tall. These two structures are connected by trestles and a transfer station. Variations in the shape factor and the integral force coefficient of the structure were compared and analyzed under different test cases. The results indicate that when two structures are arranged in series, with the adjacent structure positioned upstream, the shape factor of the structure is most affected, resulting in a significant reduction effect at the bottom of the windward surface. Compared to the external structure, the impact of various internal stacking forms on the shape factor of the structure is relatively weak. The adjacent structure significantly improves the wind resistance of the main structure. The integral force coefficient of the structure reaches its peak when internal stacking is full and is at its lowest when there is no internal stacking.