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A Study of Navajo Textiles in the Transitional Period (19세기후반 전환시대 Navajo 인디언직물의 고찰)

  • 정미실
    • Journal of the Korean Home Economics Association
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    • v.40 no.8
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    • pp.37-48
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    • 2002
  • The purpose of this study was to survey Navajo's textiles of the transitional period(1868-1890) and to examine appearance background of those textiles. The two study questions were central to the project. 1) What were characteristics of eye-dazzler and pictorial in the transitional period? 2) How developed was the American trader's role? To perform the purpose, literatures on this subject were surveyed, investigation of textiles in Arizona State Museum and Historical Museum of Arizona were accomplished. The results of this study were as follows: 1. Eye-dazzler is called because of their small, serrate triangle and diamond patterns in intense, contrasting colors. Eye-dazzler mostly used Germantown yam and wedge-weave technique. Germantown was a plied yam colored with synthetic dyes. Wedge-weave technique used optical illusions and an undulating technique to create an effect of motion and rhythmic symmetry. 2. The Americans began to intern Navajos at Bosque Redondo, New Mexico in 1863. During their stay at Bosque Redondo, the Navajo came into greater contact with Rio Grande blankets. The influence of designs of these becomes increasingly important in the eye-dazzler. 3. Pictorial materials included rich new sources the railroad provided and living environment of animals, plants, hogans, neighbors, deities that interested the Navajo. Also, sandpainting textiles were a pictorial. Three types of textiles utilized: yei, yeibichai, and sandpainting tapestry. 4. The arrival of the railroad caused many changes for the lives and textiles of the Navajos. The railroad brought a new client into the Navajo, and the Navajos attempted new textiles with design-inspiring fresh materials to adjust taste of the eastern purchasers.

The Effect of a Bed-Backrest Elevation System Combined With Hip and Knee Flexion on Lower Extremity Body-Pressure Reduction

  • Kim, Min-Hee;Yoo, Won-Gyu;Yi, Chung-Hwi;Kim, Han-Sung;Kim, Su-Jin
    • Physical Therapy Korea
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    • v.15 no.4
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    • pp.59-63
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    • 2008
  • Pressure sores are painful and needless complications of critical illness. and manifest as a localized area of ischemic necrosis of tissue caused by pressure. This study analyzed the bed-backrest elevation system combined with hip and knee flexion for lower extremity lower pressure reduction. Eight healthy adults aged 21 to 26 years were recruited. The Body Pressure Measurement Mat of the TekScan system was used to measure the location and magnitude of the peak pressures on the body bed interface. The SPSS statistical package was used to analyze the significance of differences between the general bed-backrest elevation system and the bed-backrest elevation system combined with hip and knee flexion using the paired t-test. The result showed that the body-pressure of the lower extremity was more significantly reduced for the bed-backrest elevation system combined with hip and knee flexion ($26.6{\pm}4.3$ mmHg) than a general bed-backrest elevation system ($37.3{\pm}5.2$ mmHg) (p<.05).

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Positive and Negative Influence of Social Network on Self Rated Health and its Gendered Pattern (사회적 관계망의 긍정적, 부정적 기능이 성별 주관적 건강에 미치는 영향)

  • Park, Su-San;Cho, Sung-Il;Jang, Soong-Nang
    • Korean Journal of Health Education and Promotion
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    • v.28 no.4
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    • pp.39-49
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    • 2011
  • Objectives: This study was to examine the association between structural and functional characteristics of social network and self-rated health in middle-aged Korea population. We also explored gender difference in the relationship between social network and health. Methods: Data were collected from individuals aged 40-69 years old participating in the 2005 survey for the Korean Genome & Epidemiology Study. We examined the association between social network, social support, social conflict and self-rated health using multiple logistic regression analysis stratified by gender. Results: The extent and contact frequency of close people, and social participations were associated by not only the positive function but also the negative function of social network. Both the positive and negative functions of social network affected self-rated health. The relationship between the function of social network and health showed a gender difference: only positive function was significantly associated with health in men while only negative function had significant relationship with health in women. Conclusions: Social support and social conflict affected the health in both genders through different ways. The ambivalent effect of social network on health should be explored further.

Development and Evaluation of Wearable Device with Heat and Massage Function (안마 및 발열기능의 스마트 조끼 개발과 성능 및 만족도 평가)

  • Roh, Eui Kyung;Yoon, Mi Kyung
    • Fashion & Textile Research Journal
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    • v.22 no.5
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    • pp.676-685
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    • 2020
  • This study developed smart vests with heat and massage functions that changed patterns, designs, materials, etc., and evaluated their functions and satisfaction. A knitted fabric with good elasticity and a heating lining were used, and in consideration of this, the final vest pattern fitted to the upper body was completed. A heat pad was attached to the back, and 6 vibration motors were attached to the trapezius muscle. The controller was placed on the left chest for easy operation, and the battery was stored in an inner pocket under the controller. The heating effect of the smart vest, the location of the devices, and the ease of operation were excellent. When the massage function was operated, the thermal comfort was increased compared to when the massage function was not operated, and the high thermal comfort was perceived by the operation of heat and heat+massage function. Due to the battery, the weight, irritating contact of devices and wearing sensation decreased, but there was no reduction in wearing sensation due to heat and vibration devices. The greater the satisfaction with the massage function, thermal comfort, fit, appearance and weight, the greater the product satisfaction.

Improvement of Mechanical Interfacial Properties of Silica/Rubber Composites by Silane Coupling Agent Treatment (실란 커플링제를 이용한 실리카/고무 복합재료의 기계적 계면 물성의 향상)

  • Park, Soo-Jin;Cho, Ki-Sook;Lee, Jae-Rock
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2001.10a
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    • pp.121-124
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    • 2001
  • Surface-modified silica holds considerable promise in the development of advanced materials for good mechanical properties and stability. In this work, the surface and mechanical interfacial properties of silicas treated with silane coupling agents, such as Y-methacryloxy propyl trimethoxy silane (MPS). Y-glycidoxy propyl trimethoxy silane (GPS), and Y-mercapto propyl trimethoxy silane (MCPS), are investigated. The effect of silane surface treatments of silica on the surface properties and surface energetics are studied in terms of surface functional values and contact angle measurements. And their mechanical interfacial properties of the silica/rubber composites are studied by the composite tearing energy ($G_{IIIC}$). As a result. the mechanical interfacial properties are improved in the case of silane-treated composites compared with untreated one. It reveals that the functional groups on silica surface by silane surface treatments play an important role in improving the degree of adhesion at interfaces in a silica-filled rubber system.

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Evaluation of Machinability of Micro groove by Cutting Environments in High Speed Machining using Ball End Mill (소구경 미세홈 고속가공시 가공환경변화에 따른 가공성 평가)

  • 정연행;이태문;강명창;이득우;김정석
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2002.04a
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    • pp.32-37
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    • 2002
  • High speed machining is one of most effective technologies to improve productivity. It can give great advantage for manufacture of die and Moulds. However, when the high speed machining of materials, especially in machining of micro groove, a severely thermal demage was generated on workpiece and tool. Generally, the cutting fluid is used to improve penetration, lubrication, and cooling effect. In order to rise the performance of lubrication, it contains extreme pressure agents (Cl, S, P). But the environment of work room go bad by those additive Therefore, the compressed chilly air with Oil mist system was developed to replace the conventional cutting fluid system. This paper carried out the tests to evaluate the machinability by the cutting environment in high speed micro groove machining of NAK80 (HRC40). Compressed chilly air with oil mist was ejected on the contact area between cutting edge and workpiece. The effectiveness of this developed compressed chilly air with oil mist system was evaluated in terms of tool life. The results showed that the tool life of carbide tool coated TiAIN with compressed chilly air mist cooling was much longer than with dry and flood coolant when cutting the material.

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Fabrication and Calibration of pH Sensor Using Suspended CNT Nanosheet (부양형 탄소나노튜브 나노시트를 이용한 pH센서의 제작과 보정)

  • Ryu, Hyobong;Choi, WooSeok;An, Taechang;Heo, Joonseong;Lim, Geunbae
    • Journal of Sensor Science and Technology
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    • v.22 no.3
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    • pp.207-211
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    • 2013
  • In this research, the pH sensor was developed using CNT nanosheet with Nafion coating for the advanced medical sensor such as a blood gas analyzer. The CNT nanosheet was formed by dielectrophoresis and water-meniscus between cantilever-type electrodes. Then, the process of the heat annealing and the Nafion coating was conducted for reducing contact resistance and giving proton selectivity respectively. We measured the response of the pH sensor as the electrolyte-gated CNT-nanosheet field effect transistor. The sensor showed a linear current ratio in a similar range of the normal blood pH. A calibration method for decreasing of the response variation among sensors has also been introduced. Coefficient of variance of the pH sensor was decreased by applying the calibration method. A linear relation between the calibrated response of the sensors and pH variance was also obtained. Finally, the pH sensor with a high resolution was fabricated and we verify the feasibility of the sensor by applying the calibration method.

Effect of Washing and Subsequent Heat Treatment on Water Repellency of Silk Fabric Treated with Fluorocarbon Resins

  • Park, Hyei-Ran;Lee, Mun-Cheul
    • Textile Coloration and Finishing
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    • v.24 no.3
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    • pp.173-179
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    • 2012
  • Silk fabric treated with fluorocarbon resins (Asahi Guard AG-7005 and AG-E061) were washed and subsequently heat treated varying the washing cycles and the temperature. After the processing, the water and oil repellencies, and contact angle to water were evaluated. The water and oil repellencies decreased by the washing and recovered by following heat treatment. Also ESCA measurement was carried out to investigate the surface chemical composition of the treated fiber. The $F_1s$ intensity of the treated fabric decreased by the washing and recovered by the subsequent heat treatment. On the other hand, the $O_1s$ intensity increased by the washing and decreased by following heat treatment. From the results, it is clear that change of the water and oil repellencies of the silk fabric treated with fluorocarbon resin occurred by the washing and subsequent heat treatment. Considering a change of the water repellency of the silk fabric treated with fluorocarbon resin, it seems likely that the fluoroalkyl group of the fluorocarbon resin rotates from surface to inside of the fiber by the washing to adapt to the hydrophilic circumstance, and the orientation of the fluoroalkyl groups of the resin disturbed by the washing recovers the orientation to the fiber surface after the subsequent heat treatment.

The Effect of Bumper Mismatch on Vehicle Repair Cost (차량 간 범퍼높이 차이가 수리비에 미치는 영향)

  • Choi, Dong-Won;Park, In-Song;Hong, Seung-Jun
    • Transactions of the Korean Society of Automotive Engineers
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    • v.18 no.1
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    • pp.99-104
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    • 2010
  • It is a frequent occurrence in urban traffic - a low-speed collision in which one vehicle hits the back of another. The vehicles often sustain expensive damage. Bumpers can reduce this damage, but only line up so the initial contact in an impact is bumper to bumper. Then the bumpers on the colliding vehicles have to absorb the crash energy, keeping damage away from expensive sheet metal, lights, and other components. In real world accidents, Bumper mismatches in crashes are increasing, and the resulting repair costs from low-speed collisions are escalating. In this study, we investigated the bumper rail height and analyzed their effects on repair cost. Futhermore, Our 16kph front-into-rear crash tests demonstrates bumper mismatch problem.

Study on Structural Integrity of Bearingless Main Rotor Hub System of Helicopter (헬리콥터 무베이링 메인 로터 허브 시스템의 구조 건전성에 관한 연구)

  • Lee, Mu-Hyoung;Park, Ill-Kyoung;Kim, Sung-Joon;Hwang, In-Hee;Kim, Tae-Joo
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.20 no.4
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    • pp.50-56
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    • 2012
  • Rotor system is a very important part which produce lift, thrust and control force in helicopter. Component of rotor system must have structural integrity for applied load. The estimation of structural integrity is regarded greatly as important in aerospace field. In this study, the process of structural analysis performed for bearingless main rotor system of helicopter. The composite flexbeam and torque tube of bearingless main rotor are very thick, so 3D layered soild elements of MSC.PATRAN were used to get the finite element analysis results. To estimate structural integrity, non-linear static analysis considering geometric non-linearity is performed. In addition, detailed finete element analysis and non-linear static analysis are performed to consider the stress concentration for fitting effect and contact surface. The estimation process of structural integrity for bearingless main rotor system of helicopter may help the design.