• Title/Summary/Keyword: restricted angle

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Energy Efficient Restricted Angle-Control Flooding in Wireless Sensor Networks (무선 센서 네트워크 상에서 에너지 효율적인 제한된 영역 조절 플러딩)

  • Park, Eun-Ryung;Park, Myong-Soon
    • Journal of KIISE:Computing Practices and Letters
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    • v.16 no.7
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    • pp.804-808
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    • 2010
  • In this paper, we propose Restricted Angle-control Flooding considered density network of sensor nodes and node‘s limit energy. Restricted Angle-control Flooding, increase energy efficiency by reducing unnecessary candidate nodes involved in forwarding closer to the destination. And The Hole when faced with our proposal to raise rates data through Hole Detection which is sender‘s forwarding area is extended or broadcast to the entire network. Compared to the traditional flooding, we show the superiority at the node’s energy consumption, data rate and network lifetime through the performance.

A Study on Photoelastic Fringe Patterns in Cutting Process(II) (切削加工 의 光彈性的 現象 에 관한 硏究 (II))

  • 김정두;이용성
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.8 no.5
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    • pp.401-407
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    • 1984
  • In the previous paper, part I, the principal stresses were investigated on the normal tools and the workpieces whose materials were the same epoxy resin. In this paper, are measured and compared the stresses on the normal tools and restricted tools which have three various rake angles. Each restricted tool above has the same restricted angle. The workpieces used in this experiment are made of high quality lead. The photoelastic measuring device is attached to the saddle of the lathe and carried at the same speed as the cutting tool is feeded. The results obtained are summarized as follows; The shear stresses on the tip of the restricted tools of the rake angle .alpha.=12.deg. and .alpha.=0.deg. are less than those of normal tools. But, for the rake angle .alpha.=-12.deg., the former is greater than the latter. The result of photoelastic method shows that in the range of rapid decreasing of normal stress on the tool edge, the shear is maintaining a certain value.

Numerical study of hydrodynamic interaction on a vessel in restricted waterways

  • Lee, Chun-Ki
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.4 no.1
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    • pp.1-8
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    • 2012
  • The hydrodynamic interaction between ship and bank can't be neglected when a vessel is app- roached toward the tip of a wedge-shaped bank in restricted waterways, such as in a harbor, near some fixed obstacles, or in a narrow channel. In this paper, the characteristic features of the hydrodynamic interaction acting on a slowly moving vessel in the proximity of a wedge-shaped bank are described and illustrated, and the effects of water depth and the spacing between ship and wedge-shaped bank are summarized and discussed based on the slender body theory. From the theoretical results, it indicated that the hydrodynamic interactions decrease as wedge-shaped bank of angle ${\beta}$ in-creases. For water depth to draft ratio less than about 2.0, the hydrodynamic interactions between ship and bank in-crease sharply as h/d decreases, regardless of the wedge-shaped bank of angle ${\beta}$. Also, for lateral separation more than about 0.2L between ship and wedge-shaped bank, it can be concluded that the bank effects decrease largely as the separation increases.

A Study on lung dose of Intensity modulated and volumetric modulated arc therapy plans using restricted angle of Non-small cell lung cancer (비소세포 폐암의 제한된 각도를 이용한 세기변조와 용적변조회전 방사선치료계획의 폐 선량에 관한 연구)

  • Yeom, Misuk;Lee, Woosuk;Kim, Daesup;Back, Geummun
    • The Journal of Korean Society for Radiation Therapy
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    • v.26 no.1
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    • pp.21-28
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    • 2014
  • Purpose : For non-small cell lung cancer, if the treatment volume is large or the total lung volume is small, and the tumor is located in midline of patient's body, total lung dose tends to increase due to tolerance dose of spinal cord. The purpose of this study is to compare and evaluate the total lung dose of three dimensional conformal radiotherapy(3D CRT), intensity modulated radiotherapy(IMRT) and volumetric modulated arc therapy(VMAT) using restricted angle for non-small cell lung cancer patients. Materials and Methods : The treatment plans for four patients, being treated on TrueBeam STx($Varian^{TM}$, USA) with 10 MV and prescribed dose of 60 Gy in 30 fractions, 3D CRT, restricted angle IMRT and VAMT radiotherapy plans were established. Planning target volume(PTV), dose to total lung and spinal cord were evaluated using the dose volume histogram(DVH). Conformity index(CI), homogeneity index(HI), Paddick's index(PCI) for the PTV, $V_{30}$, $V_{20}$, $V_{10}$, $V_5$, mean dose for total lung and maximum dose for spinal cord was assessed. Results : Average value of CI, HI and PCI for PTV was $0.944{\pm}0.009$, $1.106{\pm}0.027$, $1.084{\pm}0.016$ respectively. $V_{20}$ values from 3D CRT, IMRT and VMAT plans were 30.7%, 20.2% and 21.2% for the first patient, 33.0%, 29.2% and 31.5% for second patient, 51.3%, 34.3% and 36.9% for third patient, finally 56.9%, 33.7% and 40.0% for the last patient. It was noticed that the $V_{20}$ was lowest in the IMRT plan using restricted angle. Maximum dose for spinal cord was evaluated to lower than the tolerance dose. Conclusion : For non-small cell lung cancer, IMRT with restricted angle or VMAT could minimize the lung dose and lower the dose to spinal cord below the tolerance level. Considering PTV coverage and tolerance dose to spinal cord, it was possible to obtain IMRT plan with smaller angle and this could result in lower dose to lung when compared to VMAT.

유한요소법에 의한 공구인선의 응력분포에 관한 연구

  • Kim, Jeong-Du
    • Journal of the Korean Society for Precision Engineering
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    • v.1 no.1
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    • pp.50-58
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    • 1984
  • In the present paper are calculated and compared the stresses on the normal tools and the restricted tools which have three various rake angles by Least Square Method. The results obtained are summerized as follows. The tool displacement at rake angle .alpha. = 12 .deg. and .alpha. = 0 .deg. is positive value in the principal cutting direction and negative value in the feed direction. At rake angle .alpha. = -12 .deg. the displacement is negative value in both of directions. The principal stress of the restricted and normal tool is maximum at the tip of the tool, the shear stress is maximum after a certain distance from the tip. The result of FEM and P.E method shows that in the range of rapid decreasing of normal stress of the tool edge, the shear stress is maintaining a certain value. This is due to the friction characteristic of the chip.

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Design of Switched Reluctance Motor for Minimizing the Torque Ripple (스위치드 릴럭턴스 전동기의 토오크 리플 저감 설계)

  • Kim, Youn-Hyun;Choi, Jae-Hak;Kim, Sol;Lee, Ju;RhYu, Se-Hyun;Sung, Ha-Kyung;Im, Tae-Bin;Borm, Jin-hwan
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.51 no.7
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    • pp.339-350
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    • 2002
  • Pole arcs, turn-on angle, and turn-off angle are major design factors, which affects Switched Reluctance Motor's torque performance. If these design factors are considered independently, the enhancement of SRM performance is restricted. Therefore, we need to consider pole arcs, turn-on angle and turn-off angle at the same time, when we design SR. In this paper, we analyze how these factors affect to torque ripple and average torque by using dynamic Finite Element Method(FEM) with derive circuit and present the good design results according to the various speeds. Especially, we formulate turn-on and turn-off angle from a voltage equation and present effective design range.

Kinmatics Analysis of pelvis and lower extremity using orientation angles during a developpe a la seconde (Developpe a la seconde 동작 시 골반과 하지의 지향각(Orientation angles)의 운동학적 분석)

  • Jung, Chul-Jung;Jeung, He-Jin
    • Korean Journal of Applied Biomechanics
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    • v.14 no.3
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    • pp.259-270
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    • 2004
  • The purpose of this study was to analysis of pelvis and lower extremity using orientation angles during a developpe a la seconde. Data were collected by Kwon3D program. Two females professional modem dancer were participated in this experiment. Subjects performed a developpe a la seconde in meddle heights(about 90 dog.) The results were as follows. The orientation angles of pelvis were, in most cases, caused by the movement of trunk and thigh. It was restricted the movement of pelvis within narrow limits because the movement of pelvis was very important to lower extremity alignment. The orientation angle of shank against thigh showed a change of angle about $3-6^{\circ}$ in internal external rotation. The orientation angle of foot against shank showed a change of angle about $6-7^{\circ}$ in internal external rotation.

The Influence of Restricted Arm Swing on Symmetry, Movement of Trunk and Pelvis Rotation according to Using a Mobile Phone

  • Chu, Jae-Hyeung;Kim, Yun-Jin;Ko, Yu-Min;Park, Ji Won
    • The Journal of Korean Physical Therapy
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    • v.29 no.1
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    • pp.33-38
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    • 2017
  • Purpose: This study was conducted to investigate the effects of variations in arm swing during gait on movement of the trunk and pelvis. During the gait task, the angle of the trunk and pelvic rotation were analyzed according to arm swing conditions. Methods: Seventeen healthy males participated in this study. All subjects were analyzed for gait on a treadmill three times each under three different types of arm swing conditions - natural arm swing, restricted arm swing using a phone, restricted swing in both arms. 3-D motion analysis systems were used to collect and analyze the kinematic data of trunk and pelvic movements, and repeated one-way ANOVA was used to compare the trunk and pelvic kinematic data and symmetry index. The level of significance was ${\alpha}=0.05$. Results: The results showed kinematic differences in trunk and pelvic during gait based on the arm swing conditions. Specifically, there were significant differences in trunk rotation, left and right trunk rotation and symmetry index of trunk rotation during gait among the three arm swing conditions. ROM was used to calculate a symmetry index (SI) based on the average left and right trunk rotation in which a value closer to zero indicated better balance. The SI obtained for arm swing restricted with the phone was closer to -1 than the other conditions. Conclusion: Restricted arm swing due to use of a phone had the possibility to induce instability of postural control while walking, which could be seen to suggest a risk of falling during gait.

Research about Designation of Restricted Area Dedicated for Remote Piloted Aircraft Flight Test (무인항공기 비행시험 전용 제한구역 설정에 관한 연구)

  • Kee, Yeho
    • Journal of Aerospace System Engineering
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    • v.9 no.2
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    • pp.25-33
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    • 2015
  • Global market of unmanned aircraft(UA) is rapidly expending based on the versatile and efficient utility of the UA. Domestically many industries, universities and research institutes are trying to do research and development of the UA in various angle of aspect. In spite of these effort, all the participants of research and development of the UA has been suffering the difficulty of acquiring the airspace around vicinity of Goheung airfield for the flight test of UA. Although the current procedure of execution of the flight test of UA is set after acquiring the airspace by applying the NOTAM(Notice To Air Man) to the Ministry of Land, Infrastructure and Transport(MLIT) at least 7 days before the flight test and commencing with the publication of the NOTAM by MLIT, if the flight test is carried out as planned, changing or reapplying the NOTAM expends mort time and makes difficulty often. Therefore it is needed that a restricted airspace for the flight test of UA is established and make all the executioner of flight test uses the exclusive airspace without limitation. This research proposes the restricted airspace with short term and long term establish requirement of airspace separately. The short term requirement has been established with the airspace of 10 nm radius and 8,000 ft altitude in which the requirements of flight test can be carried out more than 90% without needs of supplement of the additional airspace. The long term has been established within the airspace of 30 nm radius which is the maximum Radio Line Of Sight(RLOS) and 8,000 ft altitude with exclusion of current air way, airport control area, approaching corridor to the airport, existing restricted area(RA) and Military Operating Area(MOA) for the purpose of minimizing inconvenience of the other airspace user. Once establishing the exclusive airspace for the flight test of UA, research and development of industries, universities and research institutes will be more vigorous and contributes to the national economy.

Basic Study of the Improvement of PSD Output by Inclined Light Input (PSD의 출력특성향상을 위한 경사 입력광의 특성해석에 대한 기본연구)

  • Kweon, Hyun-Kyu;Park, Chang-Yong
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.9 no.4
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    • pp.53-58
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    • 2010
  • In this paper, the output characteristics of PSD(Position Sensetive Detector) used in measurement system are described. Most of the precision measurment systems are accomplished by a laser diode(LD), a photo diode(PD) and PSD(Position Sensetive Detector), which are used in reflection of mirror or projection of infrared spectrometer. But it is especially restricted by resolution of PD and PSD in nano-measurement. A new inclined light methods into the PSD are employed in the surface measurement system for increasing the resolution. As the results, we can know that the output characteristics of detective senser (PSD) become more than 2 or 3 times by changing inclined angle(range: 5 degree) compared with common angle. In addition, the experiment results are confirmed that the change of inclined angle is not affecting to the linearity and repeating.