• Title/Summary/Keyword: Shrink

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A Study on the Mechanical Properties of Shrink-Resistant Wool Fabric Treated with Enzyme (효소에 의한 방축가공 양모직물의 물성 변화에 관한 연구)

  • 박미라;김환철;박병기
    • Textile Coloration and Finishing
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    • v.13 no.3
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    • pp.155-164
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    • 2001
  • Textile wet-processing industry usually five rise to environmental pollution problems caused by using chemical substance. The objective of this study is to apply enzymes for wool and reduce the environmental problems. Three commercial protein degradation enzymes and a cellulose degradation enzyme as a reference were treated to prevent the shrinkage of wool fabric on laundering. Shrink resistant effects used change with the kinds of enzyme, the amount of enzyme, assistant chemicals, and the pre-treatment condition of wool fabric. When pre-treated with corona before enzyme treatment under ultrasonic condition, the weight loss was increased and strength was decreased and elongation was increased. Both corona pre-treatment and the addition of $Na_2SO_4$ also decreased shrinkage of wool fabrics on laundering. The existence of assistant chemicals increased alkali solubility of wool fabrics.

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Complete 3D Surface Reconstruction from Unstructured Point Cloud

  • Kim, Seok-Il;Li, Rixie
    • Journal of Mechanical Science and Technology
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    • v.20 no.12
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    • pp.2034-2042
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    • 2006
  • In this study, a complete 3D surface reconstruction method is proposed based on the concept that the vertices, of surface model can be completely matched to the unstructured point cloud. In order to generate the initial mesh model from the point cloud, the mesh subdivision of bounding box and shrink-wrapping algorithm are introduced. The control mesh model for well representing the topology of point cloud is derived from the initial mesh model by using the mesh simplification technique based on the original QEM algorithm, and the parametric surface model for approximately representing the geometry of point cloud is derived by applying the local subdivision surface fitting scheme on the control mesh model. And, to reconstruct the complete matching surface model, the insertion of isolated points on the parametric surface model and the mesh optimization are carried out. Especially, the fast 3D surface reconstruction is realized by introducing the voxel-based nearest-point search algorithm, and the simulation results reveal the availability of the proposed surface reconstruction method.

A Study on the Changes of Cystine contents and Physical Properties of Permanent Pleats Finshed Wool Fabrics (모직물의 Permanent Pleats 가공에 의한 시스틴 함량 및 물성변화에 관한 연구)

  • Lee Dong-Hwa;Kim Eun-Ae
    • Journal of the Korean Society of Clothing and Textiles
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    • v.13 no.2 s.30
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    • pp.137-145
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    • 1989
  • The purpose of this study was to investigate the effect of the permenent pleats finish on the cystine contents and the physical properties of wool fabrics. Monoethanolamine Sulfite (MEAS) was used as a reducing agent. Cystine contents of the fabrics were determined after the fabric was treated with various MEAS concentrations and steamset time. The cystine contents were increase as the MEAS concentrations were increased. The cystine contents were also increased with steamset time. As the settability showed close relationship with the cystine contents, breakdown and rebuilding of the cystine linkage was thought to play an important role for the settability. Physical properties such as shrink resistance, crease recovery angle and tensile strength were increased as the MEAS concentration was increased. As the stramset time was increased, shrink resistance and crease recovery angle were in creased.

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Shrinkages of Prefrozen or Presteamed Wood (전처리(前處理) 목재(木材)의 수축율(收縮率) 변화(變化))

  • Kang, Ho-Yang
    • Journal of the Korean Wood Science and Technology
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    • v.22 no.1
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    • pp.66-71
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    • 1994
  • To increase drying rate and reduce drying degradation, pretreatments such as prefreezing and presteaming have been widely used in wood industries. Presteaming lumbers prior to kiln drying is known positively to improve its permeability, to increase diffusion coefficient and to reduce discoloration, but negatively to increase collapse. Prefreezing lumbers prior to kiln drying is also known to reduce significantly its drying defects and its shrinkages. Thus it is no doubt that the pretreated lumbers shrink diversely from the untreated. In this study the shrinkage behaviors of the pretreated specimens are investigated by drying two tropical hardwoods (Apitong and Taun) in three different dying conditions: high temperature and slow drying rate (drying in a closed cylinder), high temperature and rapid drying rate (drying in an oven) and low temperature and slow drying rate(drying at room temperature). The prefrozen specimens show the least volumetric shrinkages in most drying conditions. The specimens dried in cylinders shrink most among all drying conditions. In general the pretreated specimens reached the 30 % moisture content faster than the untreated by about 30 %.

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Expansion Factors of Cement Mortar Containing Expanding Admixture (팽창재를 포함한 시멘트 모르터의 팽창 요인)

  • 황인동;염희남;정윤중
    • Journal of the Korean Ceramic Society
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    • v.37 no.6
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    • pp.576-582
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    • 2000
  • Two type of expanding cement generally referred to as CSA with Hauyne(3CaO 3Al2O3 CaSO4) and Quick lime(CaO). Hauyne is formed to ettringite when there are presented with CaO and CaSO4, and CaO reacts wtih water to form Ca(OH)2. REcently, the mechanism of compensation and expand mortar or concrete tend to same and it has been used improving on its shrink property. The volume of cement paste varies with its water content shrink with drying and re-wetting. Concrete and mortar works are required shrinking compensation and expansion properties to reduce of potential crack. The use of expansion cement may improve on its shrinking volume changes. CSA dosages for shrinking compensation limited by cement weight, but obtained difference expansion rate with varied W/C or inorganic admixture. This paper studies expansion rate according to expansion cement dosages, water and inorganic admixtures as Silica fume. Therefor, the expansion factor has to considered before the application.

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Shrink-wrapping based surface reconstruction from cross sectional images (표면 축소포장에 기반한 단층영상으로부터의 표면 재구성)

  • Park Eun-Jin;Choi Young-Kyu
    • Proceedings of the Korean Information Science Society Conference
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    • 2006.06a
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    • pp.133-135
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    • 2006
  • 단층촬영영상(Tomographic cross-section images)으로부터 임의의 등밀도 표면(iso-density surface)을 재구성하기 위한 새로운 방법을 제안하였다. 이 방법에서는 마칭큐브 알고리즘에 비해 정밀도는 떨어지지만 안정적인 표면을 생성하는 셀경계 알고리즘(Cell-Boundary Method)을 이용하여 초기메쉬를 구하고 이를 표면축소포장(Shrink-wrapping)처리를 통해 정밀한 등밀도 표면을 생성하게 된다. 이는 마칭큐브와 같이 단층영상에서 등밀도 표면을 직접 추출하는 것이 아니라 등밀도점(iso-density Point)을 먼저 추출하고 표면의 모호성이 없는 안정적인 초기메쉬를 이들 방향으로 축소하여 정확한 표면모델링을 가능하게 한다. 이를 통해 마칭큐브에서 발생하는 표면 결정의 모호성이 없이 보다 안정적인 표면을 정확하게 만들 수 있다.

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EPD time delay in etching of stack down WSix gate in DPS+ poly chamber

  • Ko, Yong Deuk;Chun, Hui-Gon
    • Proceedings of the Korean Society Of Semiconductor Equipment Technology
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    • 2002.11a
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    • pp.130-136
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    • 2002
  • Device makers want to make higher density chips as devices shrink, especially WSix poly stack down is one of the key issues. However, EPD (End Point Detection) time delay was happened in DPS+ poly chamber which is a barrier to achieve device shrink because EPD time delay killed test pattern and next generation device. To investigate the EPD time delay, a test was done with patterned wafers. This experimental was carried out combined with OES(Optical Emission Spectroscopy) and SEM (Scanning Electron Microscopy). OES was used to find corrected wavelength in WSix stack down gate etching. SEM was used to confirm WSix gate profile and gate oxide damage. Through the experiment, a new wavelength (252nm) line of plasma is selected for DPS+ chamber to call correct EPD in WSix stack down gate etching for current device and next generation device.

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A Fuzzy Ligic Controller for the Swell and Shrink Problems of Nuclear Steam Generators

  • Moon, Byung-Soo;Park, Jae-Chang-;Han, Kwang-Soo
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1993.06a
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    • pp.1070-1073
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    • 1993
  • A Fuzzy Logic Controller for handing the swell/shrink problems of nuclear steam generators is designed, implemented and tested on the compact nuclear simulator at Korea Atomic Energy Research Institute. Its performance is found to be better than of the PI controller originally being used. In terms of the total variations for the control actions and for the flow error curve, the ones by the fuzzy controller are found to be less than one third of those by the PI controller.

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Optimal Design of Dimension of Extrusion Die with Multi Stress Rings (다중보강링을 갖는 압출금형의 치수최적설계)

  • An, Sung-Chan;Im, Yong-Taek
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.26 no.10
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    • pp.2211-2218
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    • 2002
  • In this study, an optimal design study has been made to determine dimensions of die and multi stress rings for extrusion process. For this purpose, a thermo-rigid-viscoplastic finite element program, CAMPform, was used fur forming analysis of extrusion process and a developed elastic finite element program fur elastic stress analysis of the die set including stress rings. And an optimization program, DOT, was employed for the optimization analysis. From this investigation, it was found out that the amount of shrink fitting incurred by the order of assembly of the die set should be taken into account for optimization when the multi stress rings are used in practice. In addition, it is construed that the proposed design method can be beneficial fur improving the tool life of cold extrusion die set.

Global Policy Directions To Promote The Future Agri-Food Industry: A Focus on the Voucher Projects for Young Job Seekers and Entrepreneurs

  • Lee, Jongtae
    • Agribusiness and Information Management
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    • v.12 no.1
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    • pp.6-16
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    • 2020
  • This is a summary of a comparative study of the national policies to foster the agri-food industry implemented by the leading countries of the industry before and after the COVID-19-induced global economic crisis. By comparing the policies of each country, we discovered that key leading countries of the agri-food industry had given up or suspended one-on-one, face-to-face support programs that they had maintained for years, and have started providing financial assistance to companies or self-employed people in relative industries. Korea should implement such decisive policies for the Korean agri-food industry to tackle this unprecedented economic shrink and maintain the competitiveness of the industry. Considering the scale and speed of the spreading of the pandemic, the new policies should be implemented swiftly and boldly. This study can be used as a base material for developing new policies to minimize damage to the agri-food industry and national economy caused by COVID-19.