• Title/Summary/Keyword: unevenness

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현행 농어촌 정주권개발사업의 문제점과 개선방안 (A Study on Revising the Program for Enhancing Rural Living Environment in Korea)

  • 조영국
    • 농촌지도와개발
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    • 제12권2호
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    • pp.197-217
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    • 2005
  • Since 1990, the Korean Ministry of Agriculture and Forestry(MAF) has implemented the program for enhancing rural living environment (Jungjookunkaebal program) to stabilize rural population and community. The program has focused on providing rural areas with various social infrastructure facilities. But, because the program has been done without appropriate consideration on rural settlement system and the unevenness of rurality, people has discredit its necessity and efficacy. This paper discussed desirable strategies and tools to overcome criticism on the program.

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A study on the Hand and the Sensibility Image of Preferred Underwear Textiles

  • Kim, Hee-Sook;Na, Mi-Hee;Cho, Shin-Hyun
    • International Journal of Human Ecology
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    • 제8권1호
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    • pp.27-37
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    • 2007
  • The purpose of this study is to investigate the preference of the hand and the sensibility image of underwear textiles according to seasons. According to a recent survey of 109 college students, using a 7 scale evaluation to the preference of the hand and the sensibility image among 13 summer and 10 winter underwear textiles. The data was analyzed through mean, SD, factor analysis, t-test, Person correlation analysis and regression analysis using SPSS Win 11.0. The summer underwear textiles were classified according to six tactile factors: stiffness/surface unevenness, weight, elasticity, moistness, extension, and warm-cool and 3 sensibility image factors: elegant individual, modern, and sporty-casual. The winter textiles were classified according to six tactile factors: stiffness/surface unevenness, elasticity, warm-cool, drapability, moistness and flexibility and divided into 2 sensibility images: modern elegant and sporty-casual. Factors expressing hand and sensibility image according to season showed significant difference. In the summer, weight, in the winter, drapability and flexibility showed significant difference at the hand factor evaluation. The hand factors: weight, warm-cool and modern sensibility image factors effect the preference of summer underwear textile, also the hand factors-elasticity, stiffness/surface unevenness and the sensibility image factor-easy-sport-casual-effect the preference of winter textiles. Therefore, the thin, light, and cool textiles which are also gorgeous and sporty-casual are preferred for summer underwear textiles while soft, simple and comfortable textiles are preferred for winter textiles.

GMT-Sheet 성형품의 표면요철에 미치는 성형조건의 영향 (Effects of Molding Condition on Surface Unevenness of GMT-Sheet Moldings)

  • 김형석;김진우;김용재;이동기
    • Composites Research
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    • 제23권5호
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    • pp.30-38
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    • 2010
  • 성형조건에 따른 GMT-Sheet를 관찰하여, 성형품 표면의 불량원인을 조사했다. 현미경 관찰 결과, GMT-Sheet 성형품의 표면에서 구정, 섬유돌출, 크랙, 섬유노출, 마이크로 웰드라인, 핀홀, 여파굴곡곡선 등의 결함을 발견했다. 이 결함들은 요철의 발생원인이고, 표면 광택에 영향을 주는 현상이다. 그리고 표면거칠기에 영향을 주는 요철의 가장 주요한 발생원인은 보압 냉각 과정에서 발생하는 모재의 수축이었다. 성형 시의 보압하중이 높을수록 GMT-Sheet 성형품 표면은 좋아졌다. 또한 서냉실험에서는 탈형온도가 낮을수록 성형품의 표면이 좋아졌다.

Effect of Opening Roller Speed, Drums Speed Difference and Suction Air Pressure on Properties of Open-End Friction Spun Polyester and Acrylic Yarns

  • Vishnoi Prashant;Ishtiaque S. M.;Das A.
    • Fibers and Polymers
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    • 제6권3호
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    • pp.250-258
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    • 2005
  • The present paper is concerned with the influence of opening roller speed, drum speed difference and suction air pressure on properties of polyester and acrylic open-end friction spun yams. The results shows that the opening roller speed and the suction air pressure have considerable influence on the characteristics of polyester and acrylic open-end friction spun yams. In case of polyester yams the unevenness, imperfection and hairiness decreases and the yam tenacity increases with the increase in opening roller speed and suction air pressure. However for acrylic yams the unevenness and imperfections decreases and tenacity increases with the increase in opening roller speed and suction air pressure.

인공 삼각 돌출부의 거칠기 발현특성 (Roughness Mobilization Characteristics of Artificial Triangular Asperities)

  • 홍은수;최성웅;이인모
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2006년도 춘계 학술발표회 논문집
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    • pp.760-767
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    • 2006
  • Underestimation of rock joint shear strength comes from an inadequate consideration of roughness mobilization behavior, which is changed by asperity size as well applied normal load. In this study, we performed rock joint shear tests, and studied the roughness mobilization characteristics related with the scale of normal stress and asperities. Test specimens with artificial triangular asperities were manufactured. The specimens consisted of 3 types, and each type represented unevenness, waviness and total roughness(superposition of unevenness and waviness). The experimental results show that the roughness mobilization characteristics are varied by the scale of normal stress and asperities. Furthermore, the investigation shows that the rate of geometrical component and mechanical component in the total roughness is also varied by the scale of normal stress and asperities. These results suggest that we should consider the roughness mobilization characteristics for the roughness quantification and the shear strength modelling.

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벨트형 가연공정에서의 사도불안정에 관한 연구 (A Study on the Threadline Instability on the Belt-type Texturing Process)

  • 이민수;김승진;박경순
    • 한국염색가공학회지
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    • 제16권1호
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    • pp.5-9
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    • 2004
  • This research surveys the threadline instability on the belt texturing machine according to the 1st heater temperature, draw ratio and velocity ratio. the threadline instability to the time, which is called surging phenomena, is analysed with variations of draw ratio and velocity ratio. In addiction, the surging phenomena is investigated with the variation of the untwisting tension and false twist mechanism on the belt texturing machine. The breaking strain, modulus and yam unevenness of the DTY along the yarn length are measured and analysed with the surging phenomena which is due to untwisting tension variation on the threadline according to the draw ratio, 1st heater temperature and velocity ratio.

수도작용 붐 방제기의 수평제어장치 개발에 관한 연구 (A Study on Control System for Balancing a Boom of Self-Propelled Boom Sprayer)

  • 정창주;노현권;최영수;장영창
    • Journal of Biosystems Engineering
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    • 제22권2호
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    • pp.151-162
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    • 1997
  • Chemical application is one of the most important field operation in rice production. Rolling of a boom due to local unevenness and softness in fields causes a local under/over-application of spray. In this study, the vertical movement of boom tips due to unevenness of ground in paddy fields was investigated, and an active pendulum suspension control system was designed and tested for compensating the movement and balancing the boom to the ground. The results for testing the performance of the control system showed that the system could balance the boom both in flat and inclined fields. The active pendulum control system developed in this study could be properly used for improving spraying performance of a boom sprayer.

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GMT-Sheet 성형품의 표면요철에 미치는 섬유돌출의 영향 (Impact of Fiber Projection from GMT-Sheet Moldings on Surface Unevenness)

  • 김형석;김진우;김용재;이동기
    • Composites Research
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    • 제24권6호
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    • pp.31-36
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    • 2011
  • 성형조건에 따른 GMT-Sheet를 관찰하여, 성형품 표면의 섬유돌출을 조사했다. 섬유돌출은 모재의 수축에 의해서 성형품 표면에 생성되는 불량현상의 하나이다. 즉, 섬유돌출은 성형온도에서 상온까지 성형품이 냉각될 때 모재와 유리섬유의 수축차에 의해 발생하는 표면불량 현상이다. 성형품 표면의 섬유돌출 높이는 보압 냉각과정에서 성형압력이 클수록 작게 나타남을 알 수 있다. 성형품 표면의 섬유돌출 높이는 성형압력의 영향이 지배적임을 알 수 있다. 성형압력을 고려하여, 성형품의 표면요철 생성과정과 섬유돌출 높이 변화를 규명했다. 그리고 피복층은 표면불량 현상을 억제하는 효과가 있고, 표면으로부터 섬유돌출이나 크랙이 보이지 않았다. 피복층은 표면거칠기를 단일재료인 폴리프로필렌 정도까지 개선하였다.

GFRP 복합재료의 압축성형에서 표면요철에 미치는 성형조건의 영향 (Effects of Molding Condition on Surface Unevenness of GFRP Composites in Compression Molding)

  • 김형석;김진우;김용재;이동기
    • 대한기계학회논문집A
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    • 제34권11호
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    • pp.1649-1657
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    • 2010
  • 성형조건에 따른 GFRP 복합재료를 관찰하여, 성형품 표면의 불량원인을 조사했다. 표면거칠기에 영향을 주는 요철의 가장 주요한 발생원인은 보압 냉각 과정에서 발생하는 모재의 수축이었다. GFRP 복합재료 성형품 표면은 성형 시의 보압하중이 높을수록 좋아졌고, 서냉실험에서는 탈형온도가 낮을수록 성형품의 표면이 좋아졌다. 그리고 보압하중과 탈형온도를 고려하여, 성형품의 표면요철 생성과정과 섬유돌출 높이 변화를 규명했다.

Real-Time Water Wave Simulation with Surface Advection based on Mass Conservancy

  • Kim, Dong-Young;Yoo, Kwan-Hee
    • International Journal of Contents
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    • 제4권2호
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    • pp.7-12
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    • 2008
  • In this paper, we present a real-time physical simulation model of water surfaces with a novel method to represent the water mass flow in full three dimensions. In a physical simulation model, the state of the water surfaces is represented by a set of physical values, including height, velocity, and the gradient. The evolution of the velocity field in previous works is handled by a velocity solver based on the Navier-Stokes equations, which occurs as a result of the unevenness of the velocity propagation. In this paper, we integrate the principle of the mass conservation in a fluid of equilateral density to upgrade the height field from the unevenness, which in mathematical terms can be represented by the divergence operator. Thus the model generates waves induced by horizontal velocity, offering a simulation that puts forces added in all direction into account when calculating the values for height and velocity for the next frame. Other effects such as reflection off the boundaries, and interactions with floating objects are involved in our method. The implementation of our method demonstrates to run with fast speed scalable to real-time rates even for large simulation domains. Therefore, our model is appropriate for a real-time and large scale water surface simulation into which the animator wishes to visualize the global fluid flow as a main emphasis.