• Title/Summary/Keyword: phase space

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Experimental study on hysteretic behavior of steel moment frame equipped with elliptical brace

  • Jouneghani, Habib Ghasemi;Haghollahi, Abbas
    • Steel and Composite Structures
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    • v.34 no.6
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    • pp.891-907
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    • 2020
  • Many studies reveal that during destructive earthquakes, most of the structures enter the inelastic phase. The amount of hysteretic energy in a structure is considered as an important criterion in structure design and an important indicator for the degree of its damage or vulnerability. The hysteretic energy value wasted after the structure yields is the most important component of the energy equation that affects the structures system damage thereof. Controlling this value of energy leads to controlling the structure behavior. Here, for the first time, the hysteretic behavior and energy dissipation capacity are assessed at presence of elliptical braced resisting frames (ELBRFs), through an experimental study and numerical analysis of FEM. The ELBRFs are of lateral load systems, when located in the middle bay of the frame and connected properly to the beams and columns, in addition to improving the structural behavior, do not have the problem of architectural space in the bracing systems. The energy dissipation capacity is assessed in four frames of small single-story single-bay ELBRFs at ½ scale with different accessories, and compared with SMRF and X-bracing systems. The frames are analyzed through a nonlinear FEM and a quasi-static cyclic loading. The performance features here consist of hysteresis behavior, plasticity factor, energy dissipation, resistance and stiffness variation, shear strength and Von-Mises stress distribution. The test results indicate that the good behavior of the elliptical bracing resisting frame improves strength, stiffness, ductility and dissipated energy capacity in a significant manner.

Apparel Pattern CAD Education Based on Blended Learning for I-Generation (I-세대의 어패럴캐드 교육을 위한 블렌디드 러닝 활용 제안)

  • Choi, Young Lim
    • Fashion & Textile Research Journal
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    • v.18 no.6
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    • pp.766-775
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    • 2016
  • In the era of globalization and unlimited competition, Korean universities need a breakthrough in their education system according to the changing education landscape, such as lower graduation requirements to cultivate more multi-talented convergence leaders. While each student has different learning capabilities, which results in different performance and achievements in the same class, the uniform education that most universities are currently offering fails to accommodate such differences. Blended learning, synergically combining offline and online classes, enlarges learning space and enriches learning experiences through diversified tools and materials, including multimedia. Recently, universities are increasingly adopting video contents and on-offline convergence learning strategy. Thus, this study suggests a teaching method based on blended learning to more effectively teach existing pattern CAD and virtual CAD in the Apparel Pattern CAD class. To this end, this researcher developed a teaching-learning method and curriculum according to the blended learning phase and video-based contents. The curriculum consisted of 2D CAD (SuperAlpha: Plus) and 3D CAD (CLO) software learning for 15 weeks. Then, it was loaded to the Learning Management System (LMS) and operated for 15 weeks both online and offline. The performance analysis of LMS usage found that class materials, among online postings, were viewed the most. The discussion menu most accurately depicted students' participation, and students who did not participate in discussions were estimated to check postings less than participating students. A survey on the blended learning found that students prefer digital or more digitized classes, while preferring face to face for Q&As.

Transfiguration in Fashion Design - Focused on Stationary Space Isolated from the Body - (탈(脫)신체적 패션 디자인에 관한 고찰 - 몸과 유리된 고정 공간의 형성을 중심으로 -)

  • Yim, Eun-Hyuk
    • Journal of the Korean Society of Costume
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    • v.57 no.4 s.113
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    • pp.70-80
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    • 2007
  • Clothes and human body are inseparably related. Aesthetic consciousness of the body determines the form of clothing, reflecting the time and culture as well as the individual and society. Clothes can even reorganize the meaning of the body, while transcending their instrumental functions of protecting, expanding and deforming the body. Using 'body' to analyze the clothing form, my study develops a framework by which to classify transfiguration in fashion design. In order to inquire tile formative style and aesthetic values expressed in transfiguration in fashion, my study examines subjects from the discourse on the body to the fashion collections of the late 20th and 21st century. The results of the study are as follows. Transfiguration signifies absence of body which questions the three dimensional construction of the body in more conventional clothing system. Transfiguration is expressed in non-figural forms which implies metaphorical plasticity and abstract extensity. Transfiguration in fashion stresses a will-to-form rather than mere bodily proportion and structure, which explores trans-extensity that goes beyond the boundary of the body. Ultimately, this phase also betrays the correspondence between signifiant and $signifi\acute{e}$ in sartorial convention. Aesthetic ideal of the body is visualized in the form of a dress. Some clothes prioritize the body, particularly the feminine bodily curves, while others focus on the clothing itself as abstract and sculptural forms. Fashion continues to explore forms and images that transcend the traditional representations of the clothed body. As a type of intimate architecture, fashion always mediates the dialogue between clothes and body, or fashion and figure. My study suggests a framework to analyze bodily representation in transfiguration in fashion, focusing on the relationship between the clothes and body.

Cost Analysis of Construction Phase in Basement Composite Wall Form (지하 합벽 거푸집의 시공단계별 원가 분석에 관한 연구)

  • Choi, Oh-Young;Heo, Kyoung-Moo;Kim, Tae-Hui;Kim, Jae-Yeob;Kim, Gwang-Hee
    • Journal of the Korea Institute of Building Construction
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    • v.9 no.6
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    • pp.189-195
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    • 2009
  • Recently, the urban centralization phenomenon appears to be growing. As a result, many vigorous efforts for the use of underground space are being made. In particular, the basement depth of construction in the downtown area has deepened and construction is often done close to adjacent buildings. In this case, generally, the underground construction approach mainly used is the composite basement wall system. However, a cost analysis of the basement composite wall system does not exist. Therefore, in this study, the cost of the composite basement wall system was analyzed. The percentage breakdown of costs were: buttress work processes, 3% form work processes, 26% reinforcement work processes, 12% support work processes, 42% and other processes,17%. Accordingly, it will be necessary when developing new technology and construction methods to determine the development focus.

Impacts of Urban Green Spaces on Air Quality (도심지역 녹지의 국지적 대기환경영향에 관한 연구)

  • Joo, Hyun Soo;Kim, Seogcheol
    • Korean Chemical Engineering Research
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    • v.47 no.3
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    • pp.386-393
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    • 2009
  • This study was to find out the quantitative relation between urban treed area(neighborhood parks) and the atmosphere environment in real condition, focusing the gas-phase non-reacting air pollutants(SOx and NOx) decreasing function of trees in urban area. It also developed a quantitative analysis method for evaluation of the atmosphere influence in the type of treed areas. We set up the Pagoda Park in Seoul and its neighbourhood as a modelling area to analyse air quality impacts by urban neighbourhood park trees. From the modelling result of the Pagoda Park case study, it is concluded that urban neighbourhood park has an important meaning to suppress construction of emission sources which drive the urban polluted air quality worse, even though park's trees have relatively small air purifying function. Especially in the urban area severely contaminated by air pollutants, the first considered air quality management policy is conservation of green spaces in neighborhood park.

A Study on the Living Quarter interior design of Offshore Ship - Focused on the Living Qauter of FPSO - ("Offshore"해양특수선의 LQ실내디자인에 관한 연구 - FPSO선박의 Living Quarter를 중심으로 -)

  • Joo, Min-Kyoo;Lee, Gyoo-Baek
    • Korean Institute of Interior Design Journal
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    • v.22 no.5
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    • pp.357-366
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    • 2013
  • Global Energy Industry's high oil prices persist while their petroleum and gas production areas are entering the decline phase. More and more the drilling facilities used to bore oil from deeper depths are advancing further out into the oceans, which cause the development of "OFFSHORE" ship manufacturer facility's production demands to increase. The "OFFSHORE" ships provide a living space or L.Q (Living Quarters) for crewmen who work on the water far away from any mainland for extended periods of time. This research analyzes the LQ areas and the characterization of interior designs of different types of "OFFSHORE" ships that were built in South Korea. Also using overseas countries' Classification Society, known as "NORSOK," and analyzing their own design guidelines in conjunction with the research, the process of interior design and baseline data research was used to blueprint the new LQ areas. According to the results of the research, where ships get comprised of characteristics and operations by standards of the Classification Society's RULE, has the greatest effect on the design and design method of the LQ area. The research also shows that a conservative shipbuilding market of the Shipbuilding Company and ship owners' feelings are steadily changing to more open mindedness of acceptance. Therefore, the Korean Classification Society has to provide the new design principle to correspond to the international regulations and more various interior design plans of LQ areas needed to be present based on the new design guidelines. The capacity of the South Korean OFFSHORE shipbuilding industry is the world's top leader; however, the interior design of the LQ areas are still based from outdated designs from the 1980's. Hopefully these research results will be the cornerstone to help the shift from the outdated designs of the LQ areas to more practical modern designs.

Performance Analysis of the Uni-Directional Radiation Equiangular Antenna over EBG Surface (EBG 표면 위의 단일 방향 복사 등각 안테나의 성능 해석)

  • Yoon, Sung Hyun;Kim, Jae Kwan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.8
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    • pp.1622-1630
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    • 2015
  • In this study, we used EBG(electromagnetic band gap) reflector to change bi-directional radiation of circular polarization into uni-directional radiation of equiangular spiral antenna. When the height of spiral arm from EBG reflector is 0.07 wavelength of the lowest operating frequency, the axial ratio of the circular polarization was deteriorated. In this paper, we analyzed the magnitude and the time phase difference of $E_{\theta},E_{\phi}$ that generates right hand circle polarization that is co-polarization at +z direction and proposed the improving condition for axial ratio at all related frequency range. As a result, we obtained that the axial ratio was below 3[dB] at range of 3 ~ 10[dB], the gain was improved about 3[dB] with comparison to bi-directional radiation at free space, and $S_{11}$ was below -10[dB] at all related frequency range.

Antinociceptive Effects of Intrathecal Melatonin on Formalin- and Thermal-induced Pain in Rats (포르말린 및 열성 자극 유발 통증에 대한 척수강 Melatonin의 항침해 효과)

  • Chung, Sung Tae;Jin, Won Jong;Bae, Hong Beom;Kim, Seok Jai;Choi, Jeong Il;Kang, Myung Woo;Jeong, Chang Young;Yoon, Myung Ha
    • The Korean Journal of Pain
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    • v.19 no.2
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    • pp.137-141
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    • 2006
  • Background: It has been known that melatonin is involved in the modulation of nociceptive transmission. However, the effect of melatonin administered spinally has not been examined. Therefore, we examined the effect of melatonin on the formalin-induced or thermal-induced nociception at the spinal level. Methods: Intrathecal catheter was inserted into the subarachnoid space of male Sprague-Dawley rats. Pain was assessed by formalin test (induced by injection of $50{\mu}l$ of a 5% formalin solution to the hindpaw) or Hot-Box test (induced by radiant heat application to the hindpaw). The effect of intrathecal melatonin was examined on flinching behavior in the formalin test or withdrawal response in Hot-Box test. Results: Intrathecal melatonin produced a limited, but dose-dependent reduction of the flinching response during phase 1 and 2 in the formalin test. In addition, melatonin delivered at evening also decreased the flinching response in both phases of the formalin test. Melatonin restrictively increased the withdrawal latency in Hot-Box test. Conclusions: These results suggest that melatonin is active against the formalin- and thermal-induced nocicpetion at the spinal level, but the effect is limited.

A Study on the Characteristic and Types of Spatio-functional Differentiation by Industrial Structure in Korean Island Areas (읍·면급 섬지역의 산업구조에 의한 공간기능 분화 유형별 특성)

  • Cho, Eun Jung;Choi, Soo Myoung;Park, Yong Jin
    • Journal of Korean Society of Rural Planning
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    • v.21 no.1
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    • pp.129-141
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    • 2015
  • This study classifies the types of spatio-functional differentiation in Korean island areas and analyses typical characters and suggests the development directions by each type. Eup/Myeon-level island areas are classified as six types by the factor analysis and the cluster analysis. First type is the traditional rural center. This type puts emphasis on maintaining phase as the central space and has to maximize development potential of the whole of settlement zone. Second type is the specialized region in manufacturing industry and the qualitative mutual growth of regional industries is able to be suggested. Third type is the specialized region in the neighborhood service provision. This type needs to devise the plan for utilizing potential customers actively and developing into the region specialized in tourism industry. Fourth type is the specialized region in tourism-support service functions. This type has to promote differentiated policies for maintaining amenity infra or value of countryside capital and preservation and utilization of resources by regional features. Fifth type is the fishing industry-dominated region. This type has to promote sustainable fishery development through the policy reflecting regional features and condition. Finally, sixth type is the sluggish region dominated with the traditional agriculture and fishery. This type is needed to aim at developing into the new food production base having the advantage of clean environment by strengthening support in specialized agro-fishery products. The existing researches on spatio-functional differentiation were mostly discussed with respect to land development, but this study highlights the difference in deal with the island areas distinguished from the condition of industry.

Coherent x-ray scattering to study dynamics in thin films (결맞는 X-선 산란을 이용한 박막의 표면 거동 연구)

  • Kim, Hyun-Jung
    • Journal of the Korean Vacuum Society
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    • v.14 no.3
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    • pp.143-146
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    • 2005
  • A new method of x-ray photon correlation spectroscopy (XPCS) using coherent x-rays is developed recently for probing the dynamics of surface height fluctuations as a function of lateral length scale. This emerging technique applies the principles of dynamic light scattering in the x-ray regime. The short wavelength and slow time scales characteristic of XPCS extend the phase space accessible to scattering studies beyond some restrictions by light and neutron. In this paper, we demonstrate XPCS to study the dynamics of surface fluctuations in thin supported polymer films. We present experimental verification of the theoretical predictions for the wave vector and temperature dependence of the capillary wave relaxation times for the supported polymer films at melt for the film thicknesses thicker than 4 times of the radius of gyration of polymer. We observed a deviation from the conventional capillary wave predictions in thinner films. The analysis will be discussed in terms of surface tension, viscosity and effective interactions with the substrate.