• Title/Summary/Keyword: field orientation

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Effects of Magnetic Field Intensities for Various Lengths of Time on Orientation of Fowl Spermatozoa

  • Pham, Du Ngoc;Shinjo, Akihisa;Sunagawa, Katsunori
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.10
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    • pp.1367-1373
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    • 2001
  • This study used fowl sperm from three White Leghom rooster reared at our laboratory. Semen samples were exposed to the magnetic field strengths of from 650 to 5700 Gauss for one. two, or three days to investigate the influence of magnetic field on the orientation of fowl spermatozoa. Fowl spermatozoa were found to orient with their long axis of heads perpendicular to the magnetic field direction. The fowl spermatozoa were initially influenced when magnetic field intensities were from 650 to 5700 Gauss and the highest values (70.67, 72.49 and 71.79%) were found in the 5700 Gauss treatment at one, two, and three days exposure, respectively. Although percentages of the perpendicular oriented fowl spermatozoa increased along with the enhancement of the magnetic field intensity, the degree of orientation was only significantly higher in the treatments having the magnetic field strength from 1500 to 5700 Gauss than that in the control treatment at all exposure time. In addition, the experimental results also showed that the percentages of all orientational types of fowl spermatozoa (perpendicular category including upward perpendicular and downward perpendicular and parallel type consisting of leftward parallel and rightward parallel) in all treatments tended to be stable during exposure time. From the results of this study. it is suggested that (1) the diamagnetic anisotropy of the inside structural components of fowl spermatozoa induce them to orient perpendicular to the magnetic field direction, (2) the degree of orientation increased according to the enhancement of magnetic field strengths, (3) fowl spermatozoa had not an high sensitivity to the magnetic field, and the level of perpendicular orientation of fowl spermatozoa in this study is nearly similar to that of cattle sperm in the study of Suga et al. (2000).

The influence of magnetic field on the alignment of steel fiber in fresh cementitious composites

  • Li, Hui;Li, Lu;Li, Lin;Zhou, Jian;Mu, Ru;Xu, Mingfeng
    • Computers and Concrete
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    • v.30 no.5
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    • pp.323-337
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    • 2022
  • This paper proposes a numerical model to simulate the rotational behavior of steel fiber in fresh cement-based materials in the presence of a magnetic field. The results indicate that as the aspect ratio of fiber increases, the required minimum magnetic field intensity to make fiber rotate in viscous fluid increases. The optimal magnetic field intensity is 0.03 T for aligning steel fiber in fresh cement-based materials to ensure that the applying time of the magnetic field can be conducted concurrently with the vibrating process to increase the aligning efficiency. The orientation factor of steel fiber in cement mortar can exceed 0.85 after aligning by 0.03 T of the uniform magnetic field. When the initial angle of the fiber to the magnetic field direction is less than 10°, the magnetic field less than 0.03 T cannot make the fiber overcome the yield stress of fluid to rotate. The coarse aggregate in steel fiber-reinforced concrete is detrimental to the rotation and alignment of the steel fiber. But the orientation factor of ASFRC under the 0.03T of the magnetic field can also exceed 0.8, while the orientation factor of SFRC without magnetic field application is around 0.6.

Analysis of Level of Difficulty of Fingerprint Database by matching Orientation field (Orientation field의 정합을 이용한 지문영상 DB의 난이도 분석)

  • Park Noh-Jun;Moon Ji-Hyun;Kim Hak-Il
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.16 no.4
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    • pp.91-103
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    • 2006
  • This paper proposes a methodology to evaluate the quality and level of difficulty of fingerprint image databases, which leads to objective evaluation for the performance of fingerprint recognition system. Influencing factors to fingerprint matching are defined and the matching performance between two fingerprint images is evaluated using segmentation and orientation filed. In this study, a hierarchical processing method is proposed to measure an orientation field, which is able to improve the matching speed and accuracy. The results of experiments demonstrate that the defined influencing factors can describe the characteristics of fingerprint databases. Level of difficulty for fingerprint databases enables the performance of fingerprint recognition algorithms to be evaluated and compared even with different databases.

Relationships between achievement goal orientation and self-management in high school track & field athletes (고등학교 육상선수의 성취목표성향과 자기관리의 관계)

  • Ko, Wisug;Han, Gun-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.10
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    • pp.4445-4452
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    • 2012
  • This study examined the relationship between an achievement goal orientation and self-management in track & field athletes' of physical education high schools. Moreover, we hypothesized that the achievement goal orientation and self-management would be differed by their gender, special field, and career. Participants were 229 athletes. They completed achievement goal orientation and self-management questionnaires independently. Results from each statistical method based on the research questions revealed that there was a statistical difference in the subject goal orientation(p<0.05). Gender had a significant effect on the interpersonal, mental strength, and the body management(p<0.05). The mental strength was only statistically affected by their special field. The results indicated that the achievement goal orientation and the self-management may affect performance of high school track & field athletes. Several limitations, implications and suggestions for the future study were discussed.

Magnetic Orientations of Bull Sperm Separated into Head and Flagellum Treated by DTT or Heparin

  • Suga, D.;Shinjo, A.;Kurnianto, E.;Nakada, T.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.2
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    • pp.167-175
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    • 2000
  • This paper describes the magnetic orientation of bull sperm separated into the head and the flagellum treated by DTT or heparin in a 5,400G static field. Semen samples collected from four bulls (Japanese Black) were mixed to the same sperm density. One percentage triton X-100 was used to extract the plasma membrane. The intact and demembranated sperm suspensions were treated with 20, 200, 2,000 mM DTT, 100, 1,000 or 10,000 units heparin solutions at $4^{\circ}C$ for 6 days. The decondensation of the sperm nuclei treated by DTT or heparin was examined by measuring the head area at 1, 3 and 6 days. After measuring the area, each sample was exposed to a 5,400G static magnetic field generated by Nd-Fe-B permanent magnets for 24 hours at room temperature. Results showed that the sperms were separated into the head and the flagellum through the DTT treatment. Almost of the separated heads showed that their long axis oriented perpendicularly to the magnetic lines of force, and most of the long axis perpendicularly oriented heads showed that their flat plane oriented perpendicularly in a 5,400G magnetic field. Also, the demembranation of the head tended to increase those perpendicular orientations, while those perpendicular orientations of the head declined with the decondensation of the sperm nuclei. These findings suggest that strong magnetic anisotropy for the perpendicular orientation of the long axis and the flat plane of the head occurs in the sperm nuclei in a 5,400G magnetic field. The separated flagellum showed lower parallel orientation, and the separated and demembranated flagellum showed parallel orientation to the magnetic lines of force in this magnetic field. These findings suggest that weak magnetic anisotropy of the parallel orientation of the flagellum occurs in the inside components in a 5,400G field.

Electroactive Polymer Composites as a Tactile Sensor for Biomedical Applications

  • Kim GeunHyung
    • Macromolecular Research
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    • v.12 no.6
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    • pp.564-572
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    • 2004
  • Modem applications could benefit from multifunctional materials having anisotropic optical, electrical, thermal, or mechanical properties, especially when coupled with locally controlled distribution of the directional response. Such materials are difficult to engineer by conventional methods, but the electric field-aided technology presented herein is able to locally tailor electroactive composites. Applying an electric field to a polymer in its liquid state allows the orientation of chain- or fiber-like inclusions or phases from what was originally an isotropic material. Such composites can be formed from liquid solutions, melts, or mixtures of pre-polymers and cross-linking agents. Upon curing, a 'created composite' results; it consists of these 'pseudofibers' embedded in a matrix. One can also create oriented composites from embedded spheres, flakes, or fiber-like shapes in a liquid plastic. Orientation of the externally applied electric field defines the orientation of the field-aided self-assembled composites. The strength and duration of exposure of the electric field control the degree of anisotropy created. Results of electromechanical testing of these modified materials, which are relevant to sensing and actuation applications, are presented. The materials' micro/nanostructures were analyzed using microscopy and X-ray diffraction techniques.

EFFECT OF ORIENTATION OF A MAGNETIC FIELD ON MOTION OF AN ELECTRICALLY CONDUCTING FLUID IN A CONFINED ENCLOSURE (자장 방향 변화에 따른 밀폐공간 내 도전성 유체의 거동)

  • Han, C.Y.;Jun, H.Y.;Park, E.S.
    • Journal of computational fluids engineering
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    • v.14 no.3
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    • pp.123-130
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    • 2009
  • Hydromagnetic flow in a confined enclosure under a uniform magnetic field is studied numerically. The thermally active side walls of the enclosure are kept at hot and cold temperatures specified, while the top and bottom walls are insulated. The coupled momentum and energy equations associating with the electromagnetic retarding force as well as the buoyancy force terms are solved by an iterative procedure using the SIMPLER algorithm based on control volume approach. The changes in the flow and thermal field based on the orientation of an external magnetic field, which varies from 0 to $2{\pi}$ radians, are investigated. Resulting heat transfer characteristics are examined too.

Service quality co-orientation model : Case study of national R&D project plan evaluation service (서비스 품질 상호지향성 모형 : 국가연구개발사업계획 평가서비스 사례를 중심으로)

  • Lee, Chang-ki;Jung, Uk
    • Journal of Korean Society for Quality Management
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    • v.45 no.4
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    • pp.811-828
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    • 2017
  • Purpose: In the meantime, studies on the measurement methods of service quality have mainly been conducted in views of the service recipients. In this study, we introduce a co-orientation model that compares the perceptions of service provider and recipient and examine the applicability in service quality field. Methods: In this study, we conducted a case study on the specific service called 'National R&D Project Plan Evaluation Service' to examine the applicability of the co-orientation model in the service quality field. Results: We could identify the phenomenon of how service providers and recipients perceive differently about specific services introduced in the case study. This study confirms that it can be used to identify problems in mutually oriented service quality activities and to take practical measures to improve them. As we have seen in this case study, the co-orientation model is expected to be of great help in exploring opportunities for quality improvement in the area of service quality. Conclusion: The service quality co-orientation model allows the service provider to distinguish between what they think of differently with the service recipient and what they have in common, so the service provider will be able to find the agenda of service quality improvement.

Composition, preferred orientation and magnetic properties of Ni-Fe-Co alloy electrodeposits (Ni-Fe-Co 박막도금층의 조성, 우선배향 및 자기적 성질)

  • 예길촌;김선윤;문근호;김용웅
    • Journal of Surface Science and Engineering
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    • v.28 no.6
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    • pp.352-360
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    • 1995
  • The effect of electrolysis conditions on the composition, the magnetic properties and the preferred orientation of Ni-Fe-Co alloy deposits was investigated using the sulfate-chloride bath paddle agitated. Cathode current efficiency increases with the current density, showing the different tendency of the variation from that of the Ni-Fe electrodeposits. The Co content of the deposits decreases with increasing current density, while the content of Ni and Fe is shown to be minimum or maximum at 3A/$dm^2$ respectively. The Ni/Fe ratio of the alloy deposits is lower than that of Ni-Fe deposits. The coercive force($H_c$) of the deposits increases with the Co content in deposit, showing the relatively low value in the range of 1.8~5.0Wt.% Co. The anisotropy field ($H_k$) of the deposits is higher than that of Ni-Fe alloy deposits, The preferred orientation of the deposits is generally (200), but the orientation factor(R) changes with both the increase of current density and the magnetic field applied during deposition.

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Orientation of Liquid Crystal and Electro-Optic Characteristic Effect of dispersed Carbon nanotubes in In Plane Switching Cell (탄소 나노 튜브가 분산된 수평전기장을 이용한 액정 셀의 액정 방향성과 전기 광학특성 연구)

  • Jeon, Sang-Youn;Baik, In-Su;Lee, Seung-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.520-521
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    • 2005
  • To observe the orientation of carbon nanotubes (CNTs) dispersed in nematic liquid crystal (NLC), CNT-doped homogeneously-aligned NLC cells driven by in-plane field was fabricated. The CNTs were aligned with a LC director in the initial state, whereas the CNTs disturbed the LC director above critical ac field. We observed motional textures in the form of vertical stripes in the local area between electrodes, which were associated with a deformation of the LC director orientation. This suggests that CNTs start to vibrate three dimensionally with translational motion. The hysteresis studies of voltage-dependent transmittance under dc electric field show that the amount of residual dc is greatly reduced due to ion trapping by CNT.

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