• Title/Summary/Keyword: bulky structure

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The appearance change and heat·moisture transfer properties of knitted fabric by yarn shrinkage (원사의 수축에 따른 다공성 편성물의 형태변화와 열·수분 전달특성)

  • Sang, Jeong-Seon;Park, Juhyun;Lee, Mee-Sik;Oh, Kyung Wha
    • The Research Journal of the Costume Culture
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    • v.25 no.6
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    • pp.880-892
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    • 2017
  • In this study, the appearance change and the heat moisture transfer properties of knitted fabric by yarn shrinkage were examined to obtain useful data on the development of thermo-sensitive functional materials. Eleven types of knitted fabric were knitted using highly bulky acrylic-blended yarn. After shrinking the specimens using dry heat treatment, the appearance change and thickness were measured. An HEC simulator was adopted for measuring the heat moisture transfer properties of specimens by yarn shrinkage. When holes were arranged vertically in the mesh structure, the specimens with 2,500 and 5,000 holes showed high percent change of hole area, appearance, and thickness. When holes were diagonally arranged in the mesh structure, the percent change of hole area in the specimen with 1,250 holes was larger than the one with 2,500 holes. However, the dimensional stability of the specimen with 2,500 holes was better because of its smaller appearance and thickness change. In the tuck structure, the percent change of hole area in the specimen with 625 and 416 holes was relatively large compared with the appearance and thickness change. Furthermore, the hole size in the tuck structure was smaller than that in the mesh structure but the percent change of hole area was larger. Therefore, it was proved that the tuck structure is more suitable than the mesh structure for developing thermo-sensitive functional materials. Heat moisture transfer property test verified that the change of hole area by yarn shrinkage enabled obtaining the thermal effect due to the distinct temperature difference in the inner layer.

Modeling and Analysis of Cascade Multilevel PWM Rectifier Using Circuit DQ Transformation

  • Park, Nam-Sup
    • Journal of information and communication convergence engineering
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    • v.1 no.3
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    • pp.163-168
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    • 2003
  • This paper presents a cascade multilevel PWM rectifier without the isolation transformers for energy build-up at each inverter modules. The features and advantages of the proposed PWM rectifier can be summarized as follows; I) It realizes the high power high voltage AC/DC power conversion, 2) It uses no transformer which is bulky and heavy, 3) It has hybrid structure so that switching devices can be effectively utilized, 4) It produces high quality AC current even in high power high voltage applications, 5) The input power factor remains unity by simple modulation index control. The multilevel rectifier is analyzed by using the circuit DQ transformation whereby the characteristics and control equations are obtained. Finally, it will be shown that the system simulation reveals the validity of analyses.

International Patent Trends on Router (국내외 라우터 특허출원동향)

  • Kim Kang Hoe;Yeo Woon Dong;Yoo Jae Young;Hong Sung Hwa
    • Proceedings of the IEEK Conference
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    • 2004.06a
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    • pp.229-232
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    • 2004
  • With the internet(World Wide Web) widespread among people after 1995, Information Communication Network, which is basic structure of the internet, is rapidly changing into fiber optics communication. Voice-centered Circuit Traffic is rapidly changing into Internet-centered Packet Traffic and Optics Communication Technology can transmit 1Tb/s thousands kilometers away. The information conveyed through the internet is being diversified - from simple information based on text to bulky multimedia information such as auido & video data. So the demand for higher speed, high storage Router is on the crease. With the continued increase of Internet Traffic, Router for Core Backbone System will be much more needed.

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Technology and Market Trends on High Speed Router (초고속 라우터 기술산업동향)

  • Kim Kang Hoe;Yeo Woon Dong;Yoo Jae Young;Hong Sung Hwa
    • Proceedings of the IEEK Conference
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    • 2004.06a
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    • pp.233-236
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    • 2004
  • With the internet(World Wide Web) widespread among people after 1995, Information Communication Network, which is basic structure of the internet, is rapidly changing into fiber optics communication. The information conveyed through the internet is being diversified - from simple information based on text to bulky multimedia information such as auido & video data. So the demand for higher speed, hish storage Router is on the crease. This research aims to analyze the general trend of the patent by systematical, multilateral and segmented analysis of the technology's flow and trend, the present technological position of status and the distribution map of the technology by country, technology area using chart and graph.

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A Transformerless Cascade Multilevel PWM Rectifier with Unity Power Factor

  • Choi Nam-Sup
    • Proceedings of the KIPE Conference
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    • 2001.10a
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    • pp.576-580
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    • 2001
  • This paper presents a casca multilevel PWM rectifier without the isolation transformers for energy build-up at each inverter modules; The features and advantages of the proposed PWM rectifier can be summarized as follows; 1) It realizes the high power high voltage AC/DC power conversion, 2) It uses no transformer which is bulky and heavy, 3) It has hybrid structure so that switching devices can be effectively utilized, 4) It produces high quality AC current even in high power high voltage applications, 5) The input power factor remains unity by simple modulation index control. The multilevel rectifier is analyzed by using the circuit DQ transformation whereby the characteristics and control equations are obtained. Finally, it will be shown that the system simulation reveals the validity of analyses

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Physicochemical Properties of Dietary Fibers (식이섬유의 물리화학적 특성)

  • 황재관
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.25 no.4
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    • pp.715-719
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    • 1996
  • Dietary fibers consist mostly of complex carbohydrates such as cellulose, hemicelluloses and pectins, and also included are carbohydrate-based gums or hydrocolloids exampled as alginate, carrageenan, galactomannan xanthan, etc. Due to structural diversity, dietary fibers can be classified by various ways i.e., source, plant function, solubility, charge and topology. Understanding on the plant cell wall structure is of primary importance, since physicochemical properties of dietary fibers are dependent on the existence patterns in the cell wall. Depending on the four distinct observational dimensions, the physical parameters of dietary fibers were discussed in terms of raw sources, bulky & complex plant cell wall materials, individually separated hydrocolloid materials and specifically designed materials. Each existence state possesses the distinct physical parameters governing a variety of physiological properties of dietary fibers.

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The Surface Sizing Effect of Oxidized Starch on the Printability of Newspaper (국산 신문 용지에서 산화전분에 의한 표면 사이징 처리가 인쇄적성에 미치는 영향)

  • 하영백
    • Journal of the Korean Graphic Arts Communication Society
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    • v.15 no.2
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    • pp.25-40
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    • 1997
  • This research was carried out to investigated the effect of base paper and latex binder on printability and obtical properties of coated paper. Especially, it examined the effect of th pH of vase paper surface and functional groups of latices on the interactions between coating color components and on the structure of coated layer. It was found that the behavior of coating color containing amphoeric latex depends on the pH in the boundary region between coating color and base paper. Thus, the coating color formulated with amphoteric latex formed bulky coating layer by inducing stronger interaction between paper surface and coating components than the coating color with anionic latex. The coated paper with amphoteric latex showed better optical properties (i.e.gloss and optical) and printability (i.e. ink receptivity, wet ink receptivity, and ink set off) than the conventional anionic latex in the acidic and alkaline paper. However, dry pick strength of the coated paper was less decreased. This result indicated that amphoteric latex could also be applied practically to the alkaline paper.

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AdoMet Derivatives Induce the Production of Actinorhodin in Streptomyces coelicolor

  • Lee Yu-Kyung;Young Jung-Mo;Kwon Hyung-Jin;Suh Joo-Won;Kim Jin-Young;Chong You-Hoon;Lim Yoong-Ho
    • Journal of Microbiology and Biotechnology
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    • v.16 no.6
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    • pp.965-968
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    • 2006
  • Exogenous S-adenosyl-L-methionine (AdoMet) enhances the production of actinorhodin in Streptomyces coelicolor. Thirty compounds related structurally with AdoMet were tested for their actinorhodin production. The relationships between the structures of the compounds tested and their actinorhodin production were analyzed using computational methods, and the molecules containing both bulky substituents at the C6 position of adenine and the long 5'-alkyl chain of adenosine were predicted to show high actinorhodin production.

Synthesis of Liquid Crystalline Copolyurethanes Containing Imide Unit

  • Lee, Dong-Jin;Lee, Tae-Jung;Kim, Han-Do
    • Proceedings of the Korean Fiber Society Conference
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    • 1998.10a
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    • pp.94-97
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    • 1998
  • We have been studying :he synthesis of thermotropic polyurethanes, based on structural modifications by means of (i) the introduction of bulky substituent group in the aromatic ring to decrease the degree of lateral packing, (ii) the copolymerization of two kinds of monomers having different alkylene lengths to lower the regularity of the polymer structure, and (iii) the use of nonlinear monomers to lower the persistence length of the polymer chain in the liquid crystalline phase and to decrease the lateral interactions in the solid state. (omitted)

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Recognition of DNA Damage in Mammals

  • Lee, Suk-Hee
    • BMB Reports
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    • v.34 no.6
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    • pp.489-495
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    • 2001
  • DNA damage by UV and environmental agents are the major cause of genomic instability that needs to be repaired, otherwise it give rise to cancer. Accordingly, mammalian cells operate several DNA repair pathways that are not only responsible for identifying various types of DNA damage but also involved in removing DNA damage. In mammals, nucleotide excision repair (NER) machinery is responsible for most, if not all, of the bulky adducts caused by UV and chemical agents. Although most of the proteins involved in NER pathway have been identified, only recently have we begun to gain some insight into the mechanism by which proteins recognize damaged DNA. Binding of Xeroderma pigmentosum group C protein (XPC)-hHR23B complex to damaged DNA is the initial damage recognition step in NER, which leads to the recruitment of XPA and RPA to form a damage recognition complex. Formation of damage recognition complex not only stabilizes low affinity binding of XPA to the damaged DNA, but also induces structural distortion, both of which are likely necessary for the recruitment of TFIIH and two structure-specific endonucleases for dual incision.

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