• Title/Summary/Keyword: unevenness

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A Study on the Effect of Hand and Sensibility image on the Preference to Clothing textiles of College students -Focused on Skirt- (대학생의 의복소재 선호도에 태와 감성 이미지가 미치는 영향 -스커트용 직물을 중심으로-)

  • Kim, Hee-Sook
    • Korean Journal of Human Ecology
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    • v.14 no.1
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    • pp.133-141
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    • 2005
  • This research was designed to investigate the effect of a hand and a sensibility image on the preference to skirt textiles. 131 male and female college students were surveyed and 10 kinds of preferred fabrics were used each as a specimen for all 4 seasons. Factor analysis, t-test, Pearson's correlation, and regression were used for a statistical analysis by SPSS WIN 10.0. The results of this study are as follows: 1. In spring/fall season, 6 factors including 'elasticity/flexibility' were extracted as a hand factor, and 2 factors including 'modern elegance' were extracted as a sensibility factor in skirt textiles. 2. In summer season, 5 factors such as 'unevenness/stiffness' were extracted as a hand factor and 2 factors such as 'modern elegance romantic' as a sensibility image. 3. In winter season, 7 factors including 'elasticity' were extracted as a hand factor and 2 factors including 'modern elegance romantic' as a sensibility image. 4. Significant correlations existed between a hand and a sensibility image in spring/fall, summer, and winter. 5. A sensibility image was one of the important factors in the preference to skirt textiles in spring/fall, summer, and winter.

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Comparison of Breeding System Between Single Population and Two Sub-population Scheme by Computer Simulation I. Equal genetic level for Sub-populations

  • Oikawa, T.;Matsura, Y.;Sato, K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.10 no.4
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    • pp.422-427
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    • 1997
  • Breeding efficiency was investigated to reveal crucial factors for constructing effective breeding system with subdivided populations under equal genetic level. Simulation study of selection experiment was performed for 20 generations with 20 replications each, comparing average breeding values and inbreeding coefficients between the two breeding systems; single population scheme and two population scheme, each of which had the same genetic parameters. Genetic correlations (-0.5 to 0.5) were assumed to be caused only by pleiotropic effect of a gene. Phenotypes of the two traits generated by polygenic effect with additive 36 loci and residuals distributed normally were selected by two traits selection index procedure. Comparing between the single population scheme and the two population scheme, the single population scheme showed higher genetic gain with lower inbreeding coefficient. This result was confirmed particularly for the situation of high selection intensity, high heritability and high degree of unevenness for economic weight. Genetic correlations in the single population scheme were significantly lower than the two population scheme when initial genetic correlation was negative. When terminal crossbreeding for the two population scheme is taken into account, superiority of the two population scheme was suggested. The terminal crossbreeding was effective under the situation of long term selection, existence of moderate inbreeding depression and use of less extreme economic weight.

Design and fabrication of LGP using cross type pattern (십자패턴을 이용한 LGP의 설계 및 제작)

  • Choi, Kyu-Man;Lee, Joon-Mo;Lee, Yun-Sik;Gwon, Hyeok-Sang;Lee, Sang-Hun;Choi, Yung-Woo
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.493-494
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    • 2008
  • LGP for the small size exit was designed and fabricated. Pattern design method, which is the most important thing in the design of the LGP, was converted from the line type into the cross type. By using this new method, the brightness unevenness, which was very difficult problem to be solved in V-cutting method, was improved. Currently products had 78% of the brightness uniformity but newly developed product in this research had 87% of the brightness uniformity. Also the optimized design rule provided the improvement of the brightness of the LGP developed in this study, that has brightness of $871cd/m^2$ whichwas 98% higher than the common products.

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Study on the Physical Property of PTT/Tencel/Cotton MVS Blended Yarn for High Emotional Garment (I) - Physical property of blended yarn according to yarn structure - (고감성 PTT/Tencel/Cotton MVS 혼방사 패션소재의 물성에 관한 연구 (I) - 사 구조에 따른 혼방사 물성 -)

  • Kim, Hyun Ah
    • Fashion & Textile Research Journal
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    • v.18 no.1
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    • pp.113-119
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    • 2016
  • The evolution of spinning technology was focused on improving productivity with good quality of yarns. More detail spinning technology according to mixing of various kinds of fibre materials on the air vortex spinning system is required for obtaining good quality yarns. This paper investigated the physical properties of air vortex yarns compared with ring and compact yarns using PTT/tencel/cotton fibres. It was observed that unevenness of air vortex yarns was higher than those of ring and compact yarns, which resulted in low tenacity and breaking strain of air vortex yarns. Initial modulus of air vortex yarns was higher than those of ring and compact yarns. Yarn imperfections of air vortex yarns such as thin, thick and nep were much more than those of ring and compact yarns. These poor yarn qualities of air vortex yarn were attributed to the fasciated yarn structure with parallel fibres in the core part of the air vortex yarn. However, yarn hairiness of air vortex yarns was less and shorter than those of ring and compact yarns. Thermal shrinkage of air vortex yarns were higher than that of ring yarns, which was caused by sensible thermal shrinkage of PTT fibres on the bulky yarn surface and core part of air vortex yarns.

Fatigue life prediction of horizontally curved thin walled box girder steel bridges

  • Nallasivam, K.;Talukdar, Sudip;Dutta, Anjan
    • Structural Engineering and Mechanics
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    • v.28 no.4
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    • pp.387-410
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    • 2008
  • The fatigue damage accumulation rates of horizontally curved thin walled box-girder bridge have been estimated from vehicle-induced dynamic stress history using rain flow cycle counting method in the time domain approach. The curved box-girder bridge has been numerically modeled using computationally efficient thin walled box-beam finite elements, which take into account the important structural actions like torsional warping, distortion and distortional warping in addition to the conventional displacement and rotational degrees of freedom. Vehicle model includes heave-pitch-roll degrees of freedom with longitudinal and transverse input to the wheels. The bridge deck unevenness, which is taken as inputs to the vehicle wheels, has been assumed to be a realization of homogeneous random process specified by a power spectral density (PSD) function. The linear damage accumulation theory has been applied to calculate fatigue life. The fatigue life estimated by cycle counting method in time domain has been compared with those found by estimating the PSD of response in frequency domain. The frequency domain method uses an analytical expression involving spectral moment characteristics of stress process. The effects of some of the important parameters on fatigue life of the curved box bridge have been studied.

A hybrid method for predicting the dynamic response of free-span submarine pipelines

  • Li, Tongtong;Duan, Menglan;Liang, Wei;An, Chen
    • Ocean Systems Engineering
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    • v.6 no.4
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    • pp.363-375
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    • 2016
  • Large numbers of submarine pipelines are laid as the world now is attaching great importance to offshore oil exploitation. Free spanning of submarine pipelines may be caused by seabed unevenness, change of topology, artificial supports, etc. By combining Iwan's wake oscillator model with the differential equation which describes the vibration behavior of free-span submarine pipelines, the pipe-fluid coupling equation is developed and solved in order to study the effect of both internal and external fluid on the vibration behavior of free-span submarine pipelines. Through generalized integral transform technique (GITT), the governing equation describing the transverse displacement is transformed into a system of second-order ordinary differential equations (ODEs) in temporal variable, eliminating the spatial variable. The MATHEMATICA built-in function NDSolve is then used to numerically solve the transformed ODE system. The good convergence of the eigenfunction expansions proved that this method is applicable for predicting the dynamic response of free-span pipelines subjected to both internal flow and external current.

A Study on the Voxel Coloring using Multi-variable Thresholding (다중 가변 문턱값을 이용한 복셀 칼라링 기법에 관한 연구)

  • Kim Hyo-Sung;Lee Sang-Wook;Nam Ki-Gon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.5
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    • pp.1102-1110
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    • 2005
  • In this paper, we proposed a advanced approach to resolve the trade-off problem for the threshold value determining the photo-consistency in the previous algorithms. The threshold value for the surface voxel is substituted the photo-consistency value of the inside voxel. As iterating the voxel coloring process, the threshold is approached to the optimal value for the individual surface voxel. we present an energy minimization formulation of the binary labeling problem that surface voxels classify into opacity or transparency. The energy formula consists of the data term and the smoothness term. As considering neighboring voxels in the labeling problem, the unevenness of reconstructed surface is reduced. The labeling whose energy is the global minimum can be computed using a graph cut.

A Control Method of Driving a Paddy Vehicle Straight Ahead for Automatic Operation

  • Nagasaka, Yoshisada;Shigeta, Kazuto;Sato, Junichi
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1996.06c
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    • pp.1055-1062
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    • 1996
  • A method for automatically driving paddy vehicles, such as rice transplanters, etc., straight ahead in a paddy field was investigated . The direction of such vehicles must be precisely controlled to do the operations as straight. However, the alignment of the from wheels becomes distorted due to the unevenness of the ground, preventing the vehicle form going straight. If the proper alignment of the front wheels is maintained , the vehicle can be driven straight ahead greater precision. To investigate the influence of the ground uneveness, the behavior of a paddy vehicle running over an obstacle was quantified. The left wheel ran over an obstacle on a flat concrete road surfaced. When the steering wheel was free, the front wheels were forced toward the left when vehicle went up the obstacle and toward the right when the vehicle went down it. The torsion of the wheel when the vehicle went down the obstacle was larger than that when it went up ,so it turned right 5 degrees. Sinc hydraulic control steering decreased the steering angle , it turned right 3 degrees. These results suggest that a vehicle can be driven straight ahead with high precision when the steering angle is changed in response to the direction and inclination of the vehicle . Such results were obtained in a paddy field tests.

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Managing the Vulnerability of Megacities in North America and Europe to Seismic Hazards

  • Waugh, William L.
    • Fire Science and Engineering
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    • v.15 no.2
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    • pp.20-30
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    • 2001
  • The science and technology of seismic hazard mitigation are increasingly being shared among scientists and policy makers around the world. Administrative expertise is also being shared. While there is still tremendous unevenness in technical and administrative capacities and resources, a global community of emergency managers is developing and there is a globalization of expertise. Hazards are better understood, tools for risk assessment are improving, techniques for hazard mitigation are being perfected, and communities and states are implementing more comprehensive disaster preparedness, response, and recovery programs. Priorities are also emerging and hazard mitigation has emerged as the priority of choice in North America and Europe. An increasingly important component of hazard mitigation is resilience, in terms of increased capacities for disaster mitigation and recovery at the community and even individual levels. Each year, more is known about the locations and natures of seismic hazards, although there are still unknown and poorly understood fault lines and limited understanding of related disasters such as tsunamis and landslides. More is known about the impact of earthquakes on the built environment, although nature still provides surprises to confound man's best extorts to reduce risk. More is known about human nature and how people respond to uncertain risk and when confronted by certain catastrophe. However, despite the increased understanding of seismic phenomena and how to protect people and property, there is much that needs to be done to reduce the risk, particularly in major metropolitan areas.

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A Study on the Flow Characteristics of Vertical Impeller to Improve Flocculation Efficiency (응집효율 향상을 위한 수직형 교반기의 유동특성 연구)

  • Kim, Jin-Hoon;Park, Jong-Ho
    • 유체기계공업학회:학술대회논문집
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    • 2004.12a
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    • pp.267-274
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    • 2004
  • The optimum condition is defined as one that best suits the purpose of flocculation; the number of small particles should decrease, while that of large particles should increase. The object of this research was to develop a new impeller and substitute for conventional flocculators. The flow characteristics of turbines and hydrofoil type flocculators in turbulent fluids were observed using a standard k-$\epsilon$ Model and a computational fluid dynamics (CFD) simulation program- FLUENT The experiments were performed to compare PBT(Pitched Blade Turbine) flocculator with twisted hydrofoil type flocculators for velocity distribution, and floc formation at conventional water treatment plants in Korea. As a result of the CFD solution, twisted hydrofoil types are similar to hydrofoil flocculators for flow characteristics without regard to the twisted angle, On the other hand, it was established that turbine flocculators are greater than hydrofoil flocculators with flow unevenness and dead zone formation. Twisted hydrofoil type- II (Angle $15{\~}20^{\circ}$) is the most proper impeller for water flocculation from this point of view with a decreasing the dead zone, maintaining of the equivalent energy distribution and a drawing up of the sedimentation substance from the bottom of the flocculation basin.

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