• 제목/요약/키워드: Head position

검색결과 926건 처리시간 0.033초

최적화 기법을 이용한 HDD용 헤드 슬라이더의 부상상태 해석 (A Flying State Analysis of HDD Head Slider by Using An Optimization Technique)

  • 윤상준;김존관;최동훈;이재헌;김광식
    • Tribology and Lubricants
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    • 제8권2호
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    • pp.26-34
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    • 1992
  • This paper suggests a method to predict the flying state of the head slider in a hard disk drive (HDD) by using an optimization technique. The modified Reynolds equation for the hydrodynamic lubrication theory under the slip flow condition is used to describe the air-bearing system and a Finite Volume Method (FVM) is applied to solve the equation. Especially, Augmented Lagrange Multiplier (ALM) method is employed to find the minimum flying height, the pitch angle and the roll angle of the slider, which is shown to be faster and more general than the conventional update schemes. By using the proposed method, the variations of the flying state are analyzed as a function of the slider position in the direction of the disk radius for various disk velocities and skew angles.

풍력발전기 Air Guide 위치별 온도상승 해석 (Analysis of Temperature Rise on the Air-Guide's Position of Wind Power Generator)

  • 한창우;김현재;권기영;이학성
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2008년도 추계학술대회 논문집
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    • pp.282-285
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    • 2008
  • In this paper, the numerical analysis of the model without air-guide was carried out in wind power generator. From numerical results, the temperature rise was not satisfied for the class F insulation and the non-uniformity of temperature distribution was a wide difference in heating elements. To improve these problems, the air-guide was installed in front of the coil head of non-drive end(NDE). The short distance between coil head and air-guide was more effective than long distance in cooling performance. Compared to that of the preliminary design, it was found that the cooling performance of the modification design was improved about 12%.

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Multiple Inheritance and English Locative Inversion

  • Chung, Chan
    • 한국언어정보학회지:언어와정보
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    • 제5권1호
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    • pp.55-71
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    • 2001
  • One of the controversial issues in English locative inversion (LI) construction( e. g. Under the tree sat a woman) has been the functional status of preverbal PP and postverbal NP, i.e. whether they are a subject, a complement, or filer (topic) Based on the distributional parallelisms between the PP and NP on the one hand and an ordinary subject and filler on the other this paper proposes that the PP has a dual function as a subject and filler, while the NP also has some subject properties that the PP does not have These mixed functional properties are analyzed in the theory of HPSG expecially with the versions recently developed by Sag(1997) Manning and Sag(1999) and Ginzburg and Sag(to appear). This analysis claims that the LI construction needs to satisfy two general, independent constraints head-subject- phrase and head-filler-phrase. This position suggests that the English LI construction is an instance of the peripheral phenomena whose construction specific constraint is inherited from more general core constraints. (Dongseo University)

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Magnetic Wireless Motion Capturing System and its Application for Jaw Tracking System and 3D Computer Input Device

  • Yabukami, S.;Arai, K.;Arai, K.I.;Tsuji, S.
    • Journal of Magnetics
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    • 제8권1호
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    • pp.70-73
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    • 2003
  • We have developed a new tracking system of jaw movement. The system consists of two permanent NdFeB magnets and 32 elements of two-axial fluxgate sensor array, The two magnets are attached to head portion and front tooth. This system does not need any attachments of the head portion or mouth such as clutch or magnetic field sensor except magnets. The proposed system is applicable for five degree of freedom. Position accuracy within 2]m was achieved. We developed a 3D computer input device by using the above mentioned technique.

국내 X-선 촬영술에 있어서 실패의 원인분석에 관한 연구 (THE STUDY OF TECHNICAL FAILURE OF INTRAORAL ROENTGENOGRAPHY)

  • 강용상
    • 치과방사선
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    • 제7권1호
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    • pp.27-30
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    • 1977
  • To insure accuracy in dental roentgenographs, it is important that the patient's head position and angulation of the x-ray tube. In 1907 Cieszynski applied the rule of isometry to dental radiography and established that in the production of an accurate image of a tooth, the central ray must be porjected perpendicularly to a plane bisecting angle formed by the longitudinal axis of the tooth and the film plane. Proper exposure of the film is a part of the production of a good dental radiograph, and correct processing also makes an essential contribution to the quality of the radiograph. The author analysed the failure of exposure and processing results, and recommended followings. 1. The patient head must be positioned that occlusal plane are parallel with the horizontal floor. 2. Central ray must be projected to the objective tooth and supporting structure and projected as perpendicularly to tooth axis and film surface as possible. 3. In processing, the temperature of the solution and the processing time must be correct.

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머리전달함수를 이용한 로봇의 화자 위치 추정 (Detection of Speaker Position for Robot Using HRTF)

  • 황성목;박윤식;박영진
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 추계학술대회논문집
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    • pp.637-640
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    • 2005
  • We propose a sound source localization method using the Head-Related-Transfer-Function (HRTF) to be implemented in a given platform. HRTFs contain not only the information regarding proper time delays but also phase and magnitude distortions due to diffraction and scattering by the shading object. Therefore, a set of HRTFs for any given platform provides a substantial amount of information as to the whereabouts of the source. In this study, we introduce new phase criterion in order to find the sound source location in accordance with the HRTF database empirically obtained in an anechoic chamber with the given platform. Using this criterion, we analyze the estimation performance of the proposed method in a household environment.

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종격동내 위치한 갑상선 내 갑상설관 낭종: 증례 보고 및 문헌 고찰 (Intrathyroid Thyroglossal Duct Cyst Extending into the Mediastinum: A Case Report and Review of Literature)

  • 이찬미;홍용태
    • 대한두경부종양학회지
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    • 제38권1호
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    • pp.65-68
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    • 2022
  • Thyroglossal duct cyst (TGDC) is the most common congenital cyst in the neck and usually presents in children. It is most commonly located at the infrahyoid level. However, intrathyroid TGDC in the adult is extremely rare and its pathogenesis remains unclear. Curiously, an intrathyroid TGDC was found on the lateral aspect of the inferior pole of the thyroid gland. Given the unique position of this lesion, and its capacity to stimulate other nodules in the thyroid, it should be differentiated from other lateral neck masses, such as: thymic cysts, branchial cleft cysts, cystic hygroma, lipomas, lymphadenopathies, cervical teratomas, and lymphomas. In this case, a separate cystic mass was found in the right inferior pole of the thyroid gland and extended to the mediastinum. We confirmed it as TGDC by pathology and histological examination.

일측성 성대마비 환자에서의 후두골격수술 (Laryngeal Framework Surgery for Unilateral Vocal Fold Paralysis)

  • 차흥억;우주현
    • 대한후두음성언어의학회지
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    • 제33권2호
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    • pp.59-63
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    • 2022
  • The laryngeal framework surgery (LFS) is an operation to correct the position and tension of the vocal cords by changing the laryngeal cartilage and muscles. LFS such as type 1 thyroplasty, arytenoid adduction, and arytenopexy is performed to improve the voice of patients with unilateral vocal cord paralysis. It is known that the voice improvement effect of LFS in patients with unilateral vocal cord paralysis is excellent and lasts for a long time. LFS can also be operated under local anesthesia. Complications are not common, however, severe complications like airway obstruction could occur after the operation. Recently, several other attempts to modify the traditional surgical method have been reported. This review is intended to be helpful in understanding the characteristics and changes in laryngeal framework surgery.

퍼터헤드 회전중심점 위치 관점에서 본 남자프로골퍼의 10.94 m 퍼팅동작의 진자운동 여부 (Is Male Professional Golfers' 10.94 m Putting Motion a Pendulum Motion? From a Point of View of the Location of the Center of Putter Head Rotation)

  • 박영훈;염창홍;서국웅
    • 한국운동역학회지
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    • 제17권2호
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    • pp.217-226
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    • 2007
  • Putting score counts about 43 % of the golf score. The dominant idea of the putting motion to amateur golfers as well as to many professional golfers is a pendulum-like motion. If a golfer's putting stroke motion is a pendulum-like motion, the putting motion should be straight-back-and-through, the same backswing, downswing, and follow through length and period, and a swing with a fixed hinge joint. If the putting motions of the human are different from the pendulum motion, there could be confusion in understanding and teaching golf putting. The purpose of this study was to examine the center of rotation(COR) of the putter head to reveal whether professional golfers really putt like a pendulum. Thirteen male professional golfers were recruited for the study. Each golfers executed 10.94 m putts six times on an artificial grass mat. Putter head position data were collected through a 60 Hz three-dimensional motion analysis system and low pass filtered with cut-off frequency of 6 Hz. COR of the putter head was mathematically acquired. Each golfer's last five putting motions were considered. The results show that the COR of the putter head was neither fixed nor located inside of the golfer. The medio-lateral directional component of the COR of the putter head fluctuated in the range of 10 cm during downswing and follow through. The anterior-posterior directional component of the COR of the putter head was fixed from the beginning of the downswing through impact. Just after impact, however, it moved to the target up to 60 cm. The superior-inferior directional component of COR of the putter head moved in a superior direction with the beginning of the downswing and showed peak height just prior to impact. During the follow through, it moved back in an inferior direction. The height-normalized peak value of the COR of the putter head was $1.4{\pm}0.3$ height. Technically speaking, male professional golfers' 10.94 m putting motion is not a pendulum-like motion. The dominating idea of a pendulum-like motion in putting might come from the image of the flawless, smooth motion of a pendulum.

에드 혹 네트워크에서 최적 경로의 유효성 있는 클러스터링 알고리즘에 관한 연구 (A Study of Optimal path Availability Clustering algorithm in Ad Hoc network)

  • 오영준;이강환
    • 한국정보통신학회논문지
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    • 제17권1호
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    • pp.225-232
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    • 2013
  • 본 논문에서는 노드의 위치 정보와 유효성 경로에 따라 클러스터링내의 헤드 노드를 선출하는 방법 중 하나로 에너지 효율성을 고려한 ECOPS(Energy Conserving Optimal path Schedule) 알고리즘을 제안한다. 기존 LEACH 알고리즘은 헤드 노드를 선출할 때 노드의 에너지 확률적 분포 함수에 기반 하여 헤드 노드의 주기를 선택적으로 관리하게 된다. 그러나 이 경우 중계노드의 거리 정보 등 상황 정보 인자가 반영되지 않아 위치적으로 또는 중계노드로 적당하지 않은 노드들이 확률분포에 포함되어 헤드노드로 선택 되는 경우가 발생한다. 따라서 본 논문에서는 기존의 LEACH 기반에서 계층적인 클러스터 구조의 토폴로지로부터 헤드 노드를 선택함에 있어 인접한 노드와의 위치상황 정보인자 및 잔존에너지의 상황정보를 이용하는 ECOPS 알고리즘을 제안 한다. 제안된 ECOPS 알고리즘은 헤드 노드 교체 상황에서 후보 헤드노드 중 최적의 효율적인 에너지 보존 경로를 가지는 멤버 노드가 새로운 헤드노드로 선출됨으로써 전체 노드 수명 및 네트워크의 관리를 향상시키는 것으로 모의실험 결과를 나타내었다.