• 제목/요약/키워드: 완화장치

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Clinical Implementation of a Virtual-Micro MLC for Smoothing MLC Field Edge (다엽콜리메이터에 의한 조사경계면에서의 요동현상을 완화시켜주는 가상미세다엽콜리메이터의 임상 적용)

  • Cho Byung-Chul;Park Hee-Chul;Bae Hoonsik
    • Progress in Medical Physics
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    • v.15 no.3
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    • pp.167-172
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    • 2004
  • A Siemens HD-270 MLC$^{TM}$, a virtual-micro MLC, allows to the application of a smooth field edge method due to the finite leaf-width of MLC. This technique was implemented into a Pinnacle planning system in order to evaluate the dose distributions during the planning stage. The necessary dosimetric aspects, such as undulation and effective penumbra, were investigated with variations in the resolutions of a virtual-micro MLC and field edge angle. The positional accuracy of the couch movement was also assessed for clinical implementation. The overhead time for planning and treatment was confirmed as negligible.e.

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A Study on the Spatial Weighted Filter in AWGN Environment (AWGN 환경에서 공간 가중치 필터에 관한 연구)

  • Long, Xu;Kim, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.3
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    • pp.724-729
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    • 2013
  • Recently, with the popularization of digital devices, the requirements of image quality is becoming higher and higher. However, the images are frequently corrupted in the image data processing, there are several reasons for this and the noise is considered as the main reason. Therefore, in order to alleviate the influence of AWGN(additive white Gaussian noise) in image, this paper puts forward the spatial weighted filtering algorithm. The algorithm set the weighted value according to the spatial distance, compared with the existing methods. The algorithm not only alleviated the influence of AWGN effectively but also reserved image details.

Reduction of Coupling in Tensile and Flexure Composite Specimens (인장 및 굽힘 복합재료 시험편의 커플링 완화 방안)

  • 정일섭
    • Composites Research
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    • v.12 no.2
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    • pp.82-90
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    • 1999
  • The mechanical properties of generally orthotropic materials are conventionally measured by performing off-axis tensile and flexure tests. However, the inevitable coupling between tension and shear in case of tensile test or bending and twisting in flexure test case induces nonuniform displacement and stress fields. Consequential stress concentration along the boundary of specimens would result in inaccurate modulus and underestimated strength. This paper proposes the variation of specimen geometry in terms of appropriate obliquity of loaded boundary. For the purpose, classical lamination theory is transformed into skewed coordinate, and characteristic equations for both of unidirectional and laminated composite specimens are formulated. Finite element analysis is employed to show the validity of the skewedness in tensile and bending test specimens.

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Development of "ZIGTECHnology" Apparel for Body Shape Renovation of New Senior Life Generation

  • Cha, Su-Joung
    • Journal of the Korea Society of Computer and Information
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    • v.25 no.11
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    • pp.157-166
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    • 2020
  • In this study, I tried to develop ZIGTECHnology clothing for renovation that can correct the body shape of elderly women according to aging and delay the change of body shape. Develop and suggest corrective clothing for elderly women with easy movement that can alleviate symptoms and delay changes in body shape by analyzing body types for each symptom, such as bending of shoulders, back and waist caused by aging and diseases such as spinal curvature. As a result of the wear evaluation of the developed ZIGTECHnology clothing designs 1, 2, and 3, in terms of functionality, Design 1 was evaluated as excellent by reducing the back angle by 3.17°, but design 3 was evaluated as the most excellent considering the fit. In the clothing of elderly women, the need for clothing that complements physical shortcomings increases, so it is thought that continuous development of body shape relief devices should be made.

A Study on Automatic Surveillance System using VHF Data Link Protocol (해상이동통신에서 VHF 데이터링크 프로토콜을 이용한 자동감시시스템)

  • 장동원;조평동
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.6 no.7
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    • pp.1026-1031
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    • 2002
  • In this Paper, We analysed the technical characteristics of a automatic identification system that will introduce in aviation and marine radio stations. IMO's Marine Safety Committee approved revision of chapter V of the Safety of Life at Sea(SOLAS) Convention in 73rd meeting. According to this, AIS will become a mandatory carriage requirement by 01 July 2002. AIS as a surveillance system continuously receives its own position from the GNSS and then repeatedly broadcasts it on a W:.u data link for avoiding traffic conflicts and possible disasters. VHF data link is organized so that a specified number of time slots make up a repeatable frame. Each radio station can autonomously allocate and deallocate slots within the frame using selection algorithm which is called SOTDMA(Self-Organized Time Division Multiple Access). The results can be an aid in the continued of understanding technical characteristics for AIS as a broad surveillance system.

A Study on Automatic Surveillance System using VHF Data Link Protocol (해상이동통신에서 VHF 데이터링크 프로토콜을 이용한 자동감시시스템 연구)

  • 장동원
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2002.11a
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    • pp.187-191
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    • 2002
  • In this paper, We analysed the technical characteristics of a automatic identification system that will introduce in aviation and marine radio stations. IMO's Marine Safety Committee approved revision of chapter V of the Safety of Life at Sea(SOLAS) Convention in 73rd meeting. According to this, AIS will become a mandatory carriage requirement by 01 July 2002. AIS as a surveillance system continuously receives its own position from the GNSS and then repeatedly broadcasts it on a VHF data link for avoiding traffic conflicts and possible disasters. VHF data link is organized so that a specified number of time slots make up a repeatable frame. Each radio station can autonomously allocate and deallocate slots within the frame using selection algorithm which is called SOTDMA(Self-Organized Time Division Multiple Access). The results can be an aid in the continued of understanding technical characteristics for AIS as a broad surveillance system.

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MITIGATION OF MAXILLARY ANTERIOR TEETH PROTRUSION WITH CEREBRAL PALSY USING REMOVABLE APPLIANCE : A CASE REPORT (뇌성마비환자에서 가철성장치를 이용한 상악 전치부 돌출 완화 : 증례보고)

  • Min, Boram;Lee, Jae-Ho
    • The Journal of Korea Assosiation for Disability and Oral Health
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    • v.9 no.2
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    • pp.122-126
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    • 2013
  • Cerebral palsy is one of the primary handicapping conditions of childhood. The prevalence of malocclusions in patients with cerebral palsy is approximately twice than in general population. Even though these high rates of malocclusions, most clinicians may feel uncomfortable about treating such problems to reduce inclination of anterior teeth because to reduce of protrusion makes to decrease risk of trauma. This is the case report about mitigation of maxillary anterior teeth protrusion in patient with cerebral palsy. A 14 year old boy who had cerebral palsy visited our dental hospital. He had severe protrusive maxillary anterior teeth and narrow arch form. He was experienced at using Castillo morales appliance in early childhood. He had mild mental retardation and was able to learn simple skills. He and his parents had willing to improve his dental problems. A gentle impression taking on maxilla was done. Removable appliance was made including median screw and labial bow. We provide a period of adaption for 3 weeks. After of anterior teeth through activation of labial bow was done once a month by dentist. The treatment carried out for 10 months and we could observe reduced labial inclination of maxillary right central incisor and more wide arch form. Hawley type retainer was set at maxilla for retention. In conclusion, accompanying careful case selection and treatment, patient with cerebral palsy can be treated and should not be ignored their orthodontic needs.

An Experimental Study on the Performance of Compression-Type Anchor for CFRP Tendons (CFRP 긴장재용 압착형 정착장치의 정착성능에 관한 실험적 연구)

  • Jung, Woo-Tai;Lee, Seung-Joo;Park, Young-Hwan
    • Journal of the Korea Concrete Institute
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    • v.20 no.5
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    • pp.611-618
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    • 2008
  • CFRP (carbon fiber reinforced polymer) tendons can be used as an alternative to solve the corrosion problem of steel tendons. Since CFRP tendons are vulnerable to transverse pressure and stress concentration, the conventional anchorage system used for steel tendons can create an unreliable load carrying capacity and may result in a premature failure. Therefore, it is necessary to develop the anchorage system that is well suited for CFRP tendons. There are many types of anchorage systems for CFRP tendons, which can be classified into three types: wedge-type anchorage, bond-type anchorage, and compression-type anchorage. This paper deals with the compression-type anchorage system manufactured through swaging technology. Based on the previous test results performed by the authors, the dimension of anchorage sleeve, the use and non-use of the insert, and the compression pressure on the sleeve have been selected as the major parameters affecting the performance of the compression-type anchorage. Some anchorage sleeves have been tapered to reduce the stress concentration. Test results revealed that the performance of the anchorage system depends mainly on the dimension and the compression pressure. It has been verified that the tapered sleeve can effectively reduce the stress concentration.

Design of Rollover Prevention Controller Using Game-Theoretic Approach (미분게임 이론을 이용한 차량 전복 방지 제어기 설계)

  • Yim, Seongjin
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.37 no.11
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    • pp.1429-1436
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    • 2013
  • This study presents an approach for designing a vehicle rollover prevention controller using differential game theory and multi-level programming. The rollover prevention problem can be modeled as a non-cooperative zero-sum two-player differential game. A controller as an equilibrium solution of the differential game guarantees the worst-case performance against every possible steering input. To obtain an equilibrium solution to the differential game with a small amount of computational effort, a multi-level programming approach with a relaxation procedure is used. To cope with the loss of maneuverability caused by the active suspension, an electronic stability program (ESP) is adopted. Through simulations, the proposed method is shown to be effective in obtaining an equilibrium solution of the differential game.

A Study on the framework modeling of the traveler-type components based upon the National ITS Architecture (국가 ITS아키텍쳐기반의 여행자장치형 구성요소 프레임워크 모델링)

  • Choi, Jae-Hun;Kim, Young-Sup;Lee, Bong-Gyou
    • Journal of Korea Spatial Information System Society
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    • v.3 no.1 s.5
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    • pp.5-16
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    • 2001
  • ITS (Intelligent Transport System) has been developed into the full service leading to a new life style with the various services from private sector, which was intended to prevent the traffic accidents and to reduce the traffic jams. Since traveler-type components used in ITS services are not exclusively designed. but they can be one of the existing devices such as mobile phone, PDA, PC, KIOSK and etc. We need to consider that these devices are equipped to support ITS related services. Therefore, this study modeled, through UML, a framework of portable components based on the present national ITS architecture; the purpose being that private companies may be able to develop portable components with concepts of ITS services. The methodology of the modeling process we followed consisted of four steps: (1) analyzing service-related subsystems, (2) generalizing equipment-package and functional specifications. (3) describing information and function specific reference models, and (4) UML modeling of the reference model.

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