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Analysis of Cross Sectional Ease Values for Fit Analysis from 3D Body Scan Data Taken in Working Positions

  • Nam, Jin-Hee;Branson, Donna H.;Ashdown, Susan P.;Cao, Huantian;Carnrite, Erica
    • International Journal of Human Ecology
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    • v.12 no.1
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    • pp.87-99
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    • 2011
  • Purpose- The purpose of this study was to compare the fit of two prototype liquid cooled vests using a 3D body scanner and accompanying software. The objectives of this study were to obtain quantitative measurements of ease values, and to use these data to evaluate the fit of two cooling vests in active positions and to develop methodological protocol to resolve alignment issues between the scans using software designed for the alignment of 3D objects. Design/methodology/approach- Garment treatments and body positions were two independent variables with three levels each. Quantitative dataset were dependent variables, and were manipulated in 3x3 factorial designs with repeated measures. Scan images from eight subjects were used and ease values were obtained to compare the fit. Two different types of analyses were conducted in order to compare the fit using t-test; those were radial mean distance value analysis and radial distance distribution rate analysis. Findings- Overall prototype II achieved a closer fit than prototype I with both analyses. These were consistent results with findings from a previous study that used a different approach for evaluation. Research limitations/implications- The main findings can be used as practical feedback for prototype modification/selection in the design process, making use of 3D body scanner as an evaluation tool. Originality/value- Methodological protocols that were devised to eliminate potential sources of errors can contribute to application of data from 3D body scanners.

AN IMMUNOHISTOCHEMICAL STUDY ON PROLIFERATING CELL NUCLEAR ANTIGEN, α-1-ANTICHYMOTRYPSIN, FIBRONECTIN, TRANSGLUTAMINASE IN INFLAMMED GINGIVA (염증성 치은에서 Proliferating Cell Nuclear Antigen(PCNA),α-1-antichymotrypsin, Fibronectin, Transqlutarninase의 분포에 관한 면역조직화학적 연구)

  • Kim, Jae-Hyeon;Yoo, Hyung-Keun;Kim, Seong-Ho
    • Journal of Periodontal and Implant Science
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    • v.25 no.2
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    • pp.253-266
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    • 1995
  • Recently, available interests concerning the biologic significance of the extracellular matrix and proliferating cells associated with periodontal disease has been increased. The distribution or expression of cellular proliferation by PCNA, macrophage detection by α-l-antichymotrypsin, fibronectin playing a important role in host defence mechanisms indirectly, and transglutaminase that cross linked to fibronectin and stimulate fibrin stabilization were studied in inflammed and healthy gingiva. The excised tissue samples were fixed neutral formalin for 24 hours, embedded with paraffin, sectioned at 4-61lffi in thickness, and immunohistochemically processed by LSAB method. The positive reaction to PCNA was localized in the suprabasal and basal layer of inflammed gingiva and an increasing reactivity was observed than healthy gingiva. α-I-antichymotrypsin positive cells were localized in the basal layer of inflammed gingiva, and there was no or rare positive cells in healthy gingiva. The positive reaction to fibronectin in inflammed gingiva was more than healthy gingiva,"and shown in the connective tissue subjacent to basement membrane of epithelium and in the periphery of the collagen fiber bundles. The positive cells by transglutaminase in inflammed gingiva were noted in suprabasal, spinous, and keratin layer of epithelium, and slightly increased in the capillaries of connective tissues. But the results of this study demonstrated in vitro reaction. Therefore, the role of PCNA,α-l-antichyrnotrypsin, transglutaminase, fibronectin and coefficient with other growth factor and extracellular matrix were further investigated in vivo.

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A Study on the Interlaminar Fracture Toughness of Hybrid Composites (하이브리드 복합재료의 층간파괴인성치에 관한 연구)

  • Kim, Hyung-Jin;Gwark, Dae-Won;Lee, Hern-Sik;Kim, Jae-Dong;Koh, Sung-Wi
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.40 no.4
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    • pp.328-336
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    • 2004
  • This paper describes the effect of loading rate, specimen geometries and material properties for ModeⅠ and Mode Ⅱ interlaminar fracture toughness of hybrid composite by using double cantilever beam (DCB) and end notched flexure (ENF) specimen. In the range of loading rate 0.2~20mm/min, there is found to be no significant effect of loading rate with the value of critical energy release rate (Gc).The value of Gc for variation of initial crack length are nearly similar values when material properties are CF/CF and GF/GF, however, the value of Gc are highest with the increasing intial crack length at CF/GF. The SEM photographs show good fiber distribution and interfacial bonding of hybrid composites when the moulding is the CF/GF.

A Study on the Conservation of Lady Shim's Costume Excavated in Jecheon Province (제천출토 청송심씨 출토유물의 보존처리)

  • Park, Bong Soon;Lee, Mok Kun;Chang, In Woo
    • Journal of the Korean Society of Costume
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    • v.65 no.7
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    • pp.47-59
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    • 2015
  • This paper studies the conservation treatment of Lady Shim's costume, which was excavated in Jecheon Province in 2012. There were the significant problems, which were encountered in the treatment of the costume ; First the Jeogoris were transformed during the excavation, Second fibers were seriously deteriorated, Third most of the fabrics such as Chusa were readily deformed. To overcome these problems and to secure stability in the conservation treatment, we decided to alternate between two different washing methods ; dry cleaning by n-hexane and wet cleaning by water. The costume shape was recovered by steaming and by swelling with Hanji(Korean traditional paper). The combined cleaning method proved to be relatively efficient and stable. In addition, the shape of Chusa was well preserved by dry cleaning.(using n-hexane also solved the problem of bad smell after washing with organic solvents.) The effects of the conservation treatment on the excavated costumes could be seen in the change of Lab color difference. Washing made the distribution of Lab color difference narrower, which may suggest that the impurities on the fiber was removed by washing. In addition, the value of L was greater than a-value and b-value after the treatment. This result indicates that the change of value represents the change of color difference by cleaning.

Fabrication Process and Impact Characteristic Analysis of Metal Matrix Composite for Electronic Packaging Application (전자패키징용 금속복합재료의 제조공정 해석 및 충격특성평가)

  • 정성욱;정창규;남현욱;한경섭
    • Composites Research
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    • v.15 no.1
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    • pp.32-40
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    • 2002
  • This study developed fabrication process of SiCp/Al metal matrix composites as electronic packaging materials by squeeze casting method. The SiCp preform were fabricated in newly designed preform mold using about 0.8 % of inorganic binder(SiO2) and 5 vol.% of Al2O3fiber. To infiltrate the molten metal into the preform, fabrication condition such as the temperature and the pressure were selected. Applying the fabrication conditions, heat transfer analysis were preformed using finite element method and thus analyzed the temperature distribution and cooling characteristic during the squeeze casting. For the fabricated composites, impact toughness and thermal expansion coefficient were measured. The metal matrix composites developed in this study have 0.2~0.3 J impact toughness, 8 10ppm/C thermal expansion coefficient and 2.9 3.0g/cm3density which is appropriate properties for electronic packaging application.

Development of the Growth and Wavelength Control Technique of In As Quantum Dots for 1.3 μm Optical Communication Devices (1.3 μm 광통신용 소자를 위한 InAs 양자점 성장 및 파장조절기술 개발)

  • Park, Ho-Jin;Kim, Do-Yeob;Kim, Goon-Sik;Kim, Jong-Ho;Ryu, H.H.;Jeon, Min-Hyon;Leem, Jae-Young
    • Korean Journal of Materials Research
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    • v.17 no.7
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    • pp.390-395
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    • 2007
  • We systematically investigated the effects of InAs coverage variation, two-step annealing and an asymmetric InGaAs quantum well (QW) on the structural and optical characteristics of InAs quantum dots (QDs) by using atomic force microscopy (AFM), transmission electron microscopy (TEM) and photoluminescence (PL) measurement. The transition of size distribution of InAs QDs from bimodal to multi-modal was noticeably observed with increasing InAs coverage. By means of two-step annealing, it is found that significant narrowing of the luminescence linewidth (from 132 to 31 meV) from the InAs QDs occurs together with about 150 meV blueshift, compared to as-grown InAs QDs. Finally, the InAs QDs emitting at longer wavelength of 1.3μm with narrow linewidth were grown by an asymmetric InGaAs QW. The excited-state transition for the InAs QDs with an asymmetric InGaAs QW was not noticeably observed due to the large energy-level spacing between the ground states and the first excited states. The InAs QDs with an asymmetric InGaAs QW will be promising for the device applications such as 1.3μm optical-fiber communication.

Prediction of Effective Thermal Conductivity of Composites with Coated Short Fibers of Different Aspect Ratios Using Hybrid Model (하이브리드모델을 이용한 장단비가 다른 코팅된 단섬유를 갖는 복합재의 등가열전도계수 예측)

  • Lee, Jae-Kon;Kim, Jin-Gon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.6
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    • pp.2618-2623
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    • 2013
  • A hybrid model is proposed to easily predict the effective thermal conductivity of composites with aligned- and coated-short fibers, whose aspect ratio is not constant. The thermal conductivities of coated fillers are computed by using the generalized self-consistent model, resulting in that composites are simply simulated by the matrix with the equivalent short fibers. Finally, the thermal conductivity of the composites is predicted using the modified Eshelby model. The predicted results by the representative models and hybrid model are compared for the composite with aligned- and coated-short fibers of single aspect ratio. It is demonstrated that the hybrid model can be applied to the composite with aligned- and short-fibers of aspect ratios, 2 and 10, without any difficulties.

Dynamic Behaviors of Metal Matrix Composites in Low Velocity Impact (저속 충격하에서의 금속복합재료의 동적 특성)

  • ;Gamal A. Aggag;K.Takahashi
    • Composites Research
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    • v.12 no.1
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    • pp.68-75
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    • 1999
  • This study has observed that the dynamic behavior of Metal Matrix Composites (MMCs) in low velocity impact varies with impact velocity. MMCs with 15 fiber volume percent were fabricated by using the squeeze casting method. The AC8A was used as the matrix, and the alumina and the carbon were used as reinforcements. The tensile and vibration tests conducted yielded the yielded the tensile stress and elastic modulus of MMCs The low pass filter and instrumented impact test machine was adopted to study dynamic behaviors of MMCs corresponding to impact velocity. Stable impact signals were obtained by using the low pass filter. Impact corresponding to impact velocity. Stable impact signals were obtained by using the low pass filter. Impact energy of unreinforced alloy and MM s increased as the impact velocity increased. The increase of crack propagation energy was especially prominent, but the dynamic toughness of each material did not change much. To show the relation between crack initiation energy and dynamic fracture toughness, a simple model was proposed by using the strain energy and stress distribution at notch. The model revealed that crack initiation energy is proportional to the square of dynamic fracture toughness and inversely proportional to elastic modulus.

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Three-Dimensional Numerical Simulation of Mold-Filing and Void Formation During Vacuum-Assisted Resin Transfer Molding (VARTM 공정에서의 금형 충전 및 기공 형성에 관한 3차원 수치해석)

  • 강문구;배준호;이우일
    • Composites Research
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    • v.17 no.3
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    • pp.1-7
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    • 2004
  • In the vacuum assisted RTM (VARTM) process that has become the center of attention for manufacturing massive composite structures, a good evacuation of air in the fiber preform is recognized as the prime factor. The microvoids, or the dry spots, are formed as a result of improper gate/vent locations and the mold geometry. The non-uniform resin velocity at the flow front leads to the formation of microvoids in the fibers, whereas the air in the microvoids can migrate along with the resin flow during mold filling. The residual air in the internal voids of a composite structure may cause a degradation of the mechanical properties as well as the structural failure. In this study, a unified macro- and micro analysis methods were developed to investigate the formation and transport of air in resin during VARTM process. A numerical simulation program was developed to analyze the three-dimensional flow pattern as well as the macro- and microscopic distribution of air in a composite part fabricated by VARTM process.

Desorption characteristics of Activated Carbon and Activated Carbon Fiber by Development of Sorbent Tube for Measurement of Organic Solvent (유기용제 측정용 흡착관 개발을 위한 AC 및 ACF의 흡착특성)

  • 원정일;김기환;신창섭
    • Journal of environmental and Sanitary engineering
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    • v.17 no.3
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    • pp.99-109
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    • 2002
  • Charcoal tube/CS2 method are more popularly used than any other in the measurement of the working environment for the exposure evaluation of organic solvent, but it is some weak points that the lower accuracy can be obtained on the polar materials and within the range of the low concentration. Thus solvent desorption method has been developed to make accuracy higher and to overcome some weak points. However, because of high price of adsorption tube for thermal desorption and the short of study on its application to the working environment, it is not popularly used in the domestic industrial hygiene fields. This dissertation aims to develop thermal desorption and adsorption tubes for measuring organic solvents in the working environment, by comparing and analyzing breakthrough condition and adsorption capacity with ACF. Specific surface area of ACF used in this study is wider than the one of AC and micropore of ACF related with adsorption has been developed, and adsorption velocity and adsorption amount are very excellent by linking a pore of surface and an inside well into micropore. 1. Result of analysis on physical characteristics of adsorbent, the specific surface area of ACF was 1.3 times higher than that of AC. Distribution ratio of micropore related to adsorption was 94% on ACF and AC. Result of SEM, micropore of the AC is opened to the surface. In contrast, ACF shows that extremely fast adsorption speed. Because of micropore are exposed on the surface and penetrate through each other. 2. Breakthrough characteristics of adsorbents was not different from slop of breakthrough curve. The effluent concentration reaches 10% of initial concentration(Cout/Cin=0.1, break point) of ACF was 30~316min longer than that of AC. Therefore, the adsorption capacities of ACF was 1.1~4.6 times higher than that of AC. ACF can be used as a proper adsorbent for measurement of organic solvent.