• 제목/요약/키워드: progressive area

검색결과 276건 처리시간 0.021초

발거치에 나타난 부착상실의 양상에 대한 연구 (Periodontal attachment loss of extracted teeth for periodontal reasons)

  • 김중현;김성조;최점일;이주연
    • Journal of Periodontal and Implant Science
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    • 제36권1호
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    • pp.61-68
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    • 2006
  • The factors influencing long-term prognosis of teeth must be carefully considered. Among these, attachment level is strongly associated with tooth loss. The purpose of the present study was to estimate pattern of attachment loss based on attachment area in extracted teeth. 197 satisfied the criteria for assessment after staining. The protocol described by Waerhaug(l975) was performed. An indir ect method, based on digital image abstracted from digital camera and digital imaging software program, was used to calculate the root surface area and the attachment loss area. The data were analysed using SPSS. Except maxillary central incisior and mandibular canine, no statistical significant differences between each root surfaces were observed in anterior teeth. In posterior teeth, statistical significant differences in palatal surface of maxillary molar and mandibular molar compared with others were observed. Statistical significant difference in buccal surface compared with others was lowly observed in single and multi rooted. This study did not reveal progressive loss pattern of attachment area in each root surface but clarified root surface that has relative high loss rate of attachment area at extraction. Thus understanding this pattern of attachment loss is helpful for dentist to treat the periodontitis.

A Study on the Multi-row Progressive Die for Thin Sheet Metal Forming by Computer Simulation

  • Sim, Sung-Bo;Kim, Chung-Hwan
    • 한국기계가공학회지
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    • 제7권3호
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    • pp.75-80
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    • 2008
  • The progressive die performs a work of sheet metal processes with a piercing, notching, embossing, bending, drawing, cut-off etc. in many kinds of pressing. Now a days, these processes have been evaluated as a advanced tooling method to increase the productivity and high quality assurance. The first step analyzing of die design is production part review, then the arrangement drawing of product design and strip process layout design should be done as a next steps with a FEM simulation for its problem solution. After upper procedure were peformed, it was started to make the die, then tryout and its revision of the die and product quality, safety, productivity etc. were done continually. For the all of these process, we mobilized the theory and practice of sheet metal forming, die structure, the function and activity of die components, and the others of die machining, die material, heat treatment and know‐how so on. In this study the features of representative are production part analyzing through the FEM simulation of bending area with a considering spring back problem by DEFORM.

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고에너지 음향환경시험 튜브 개발 (Development of High Intensity Progressive Wave Tube)

  • 김영기;김홍배;문상무;우성현;임종민
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 춘계학술대회논문집
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    • pp.962-965
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    • 2005
  • A high intensity progressive wave tube is installed at Korea Aerospace Research Institute (KARI) for acoustic environmental tests. The test facility has 700 mm x 800 mm cross-sectional area, and provides acoustic environment of 165 dB over the frequency range of $25Hz{\sim}10,000Hz$. The facility consists of a 6 m long acoustic wave tube, acoustic power generation systems, gases nitrogen supply systems, and acoustic control systems. This paper describes how the basic parameters of the facility and power generation systems are controlled to meet the requirement of the test. The shape and length of the tube has been designed by using the size of test objects and the wave propagation characteristics of the tube. The capacity of acoustic power generation systems is determined by the energy conversion of acoustic wave and the efficiency of acoustic modulators. Moreover, the paper introduces test run results of the tube. Overall of 163dB has been generated by using the test facility.

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Organ Shape Modeling Based on the Laplacian Deformation Framework for Surface-Based Morphometry Studies

  • Kim, Jae-Il;Park, Jin-Ah
    • Journal of Computing Science and Engineering
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    • 제6권3호
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    • pp.219-226
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    • 2012
  • Recently, shape analysis of human organs has achieved much attention, owing to its potential to localize structural abnormalities. For a group-wise shape analysis, it is important to accurately restore the shape of a target structure in each subject and to build the inter-subject shape correspondences. To accomplish this, we propose a shape modeling method based on the Laplacian deformation framework. We deform a template model of a target structure in the segmented images while restoring subject-specific shape features by using Laplacian surface representation. In order to build the inter-subject shape correspondences, we implemented the progressive weighting scheme for adaptively controlling the rigidity parameter of the deformable model. This weighting scheme helps to preserve the relative distance between each point in the template model as much as possible during model deformation. This area-preserving deformation allows each point of the template model to be located at an anatomically consistent position in the target structure. Another advantage of our method is its application to human organs of non-spherical topology. We present the experiments for evaluating the robustness of shape modeling against large variations in shape and size with the synthetic sets of the second cervical vertebrae (C2), which has a complex shape with holes.

Magnetic Resonance Imaging as a Biomarker for Duchenne Muscular Dystrophy

  • Lim, Woo-taek
    • 한국전문물리치료학회지
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    • 제22권3호
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    • pp.98-105
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    • 2015
  • Muscular dystrophy is a hereditary musculoskeletal disorder caused by a mutation in the dystrophin gene. Duchenne muscular dystrophy (DMD) is one of the most common, and progresses relatively faster than other muscular dystrophies. It is characterized by progressive myofiber degeneration, muscle weakness and ultimately ambulatory loss. Since it is an X-linked recessive inheritance, DMD is mostly expressed in males and rarely expressed or less severe in females. The most effective measurement tool for DMD is magnetic resonance imaging (MRI), which allows non-invasive examination of longitudinal measurement. It can detect progressive decline of skeletal muscle size by measuring a maximal cross-sectional area of skeletal muscle. Additionally, other techniques in MRI, like $T_2$-weighted imaging, assess muscle damage, including inflammation, by detecting changes in $T_2$ relaxation time. Current MRI techniques even allow quantification of metabolic differences between affected and non-affected muscles in DMD. There is no current cure, but physical therapist can improve their quality of life by maintaining muscle strength and function, especially if treatment (and other forms of medical intervention) begins in the early stages of the disease.

전기제품의 프로그레시브 가공을 위한 통합적 CAD 시스템 (An Integrated CAD System for Progressive Working of Electronic Products)

  • 김재훈;김영민;김철;최재찬
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 춘계학술대회 논문집
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    • pp.829-832
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    • 2000
  • This paper describes a research work of developing a computer-aided design of product with bending and piercing for progressive working. An approach to the CAD system is based on the knowledge-based rules. Knowledge fur the CAD system is formulated from plasticity theories, experimental results and the empirical knowledge of field experts. The system has been written in AutoLISP on the AutoCAD with a personal computer and is composed of three main modules, which are input and shape treatment, flat pattern layout and strip layout module. Based on knowledge-based rules, the system is designed by considering several factors, such as radius and angle of bend, material and thickness of product, complexities of blank geometry and punch profile, bending sequence, and availability of press. Strip layout drawing automatically generated by piercing with punch profiles divided into for external area is simulated in 3-D graphic forms, including bending sequences for the product with piercing and bending. Results obtained using the modules enable the manufacturer of electronic products to be more efficient in this field.

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낙동포의 조석특성에 관한 연구 (A Study on the Tidal Characteristics of the Nakdongpo Estuary)

  • 전승환;전홍선
    • 한국항해학회지
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    • 제7권2호
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    • pp.47-63
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    • 1983
  • In this paper, we have investigated the tidal characteristics of the Nakdongpo estuary. We have carried out the analysis of harmonic constant with the use of the recorded data on tidal level at the Gadeong Do tide station and analyzed the flow velocity data obtained by ourselves at two points in the Nakdongpo estuary. In addition, we have analyzed the variation of the mean-sea level. Typical items of the characteristics we have found are; (1) The principal harmonic constants and non-harmonic constants are shown in table 2. (2) Tide in this area shows the semidiurnal inequality. (3) The mean-sea level is shown to be depressed at the rate of about 1cm to the rise of 1 mbar of the atmospheric pressure. (4) (i) At $K_2$ point, The E-W component of the velocty reveals the nature of progressive waves. The N-S component reveals the nature of stationary waves. (ii) At $K_3$ point, The E-W component shows the characteristics of progressive waves to some degree. The N-S component shows a weak hint of stationary waves. (5) At $K_2$ point, S-component is predominant due to the flow of river. At $K_3$ point, E-component is predominant due to the Tsushima current.

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전기제품의 프로그레시브 가공을 위한 공정설계 자동화 시스템 (An Automated Process Planning System for Progressive Working of Electric Products)

  • 김재훈;김철;최재찬
    • 한국정밀공학회지
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    • 제17권8호
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    • pp.198-206
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    • 2000
  • This paper describes a research work of developing automated progressive process planning system for working electric products. An approach to the CAD system in based on the knowledge-based rules. Knowledge for the CAD system is formulated from plasticity theories experimental results and the empirical knowledge of field experts. The system has been written in AutoLISP on the AutoCAD with a personal computer and is composed of three main modules which are input and shape treatment flat pattern layout and strip layout module. Based on knowledge-based rules the system is design by considering several factors such as radius and angle of bend material and thickness of product complexities of blank geometry and punch profile bending sequence and availability of press. Strip layout drawing automatically generated by piercing with punch profiles divided into for external area is simulated in 3-D graphic forms including bending sequences for the product with piercing and bending. Results obtained using the modules enable the manufacture of electronic products to be more efficient in this field.

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구속을 갖는 굽힘 및 피어싱용 제품의 프로그레시브 가공을 위한 자동화된 CAD 시스템 (An automated CAD System of Product with Bending Constraints and Piercing for Progressive Working)

  • 최재찬;김철
    • 한국정밀공학회지
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    • 제16권11호
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    • pp.174-182
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    • 1999
  • This paper describes a research work of developing a computer-aided design of product with bending constraints and piercing for progressive working. an approach to the CAD system is based on the knowledge-based rules. Knowledge for the CAD system is formulated from plasticity theories, experimental results and the empirical knowledge of field experts. The system has been written AutoLISP on the AutoCAD with a personal computer and is composed of four main modules, which are input and shape treatment, flat pattern layout, production feasibility check, and strip-layout module. Based on knowledge-based rules, the system is designed by considering several factors, such as radius and angle of bend, material and thickness of product, complexities of blank geometry and punch profile, bending sequence, availability of press. Strip layout drawing generated by piercing with punch profiles divide into automatically for external area is shown into graphic forms, including bending sequences for the product with piercing and bending constraints. Results obtained using the modules enable the designer and manufacturer of piercing and bending dies to be more efficient in this field.

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아파트 단지내 어린이 놀이터의 환경적 위상 정립에 관한 연구 (The Environmental Status of the Playgrounds located in the Apartment Housings' Area)

  • 오경진;김형언
    • KIEAE Journal
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    • 제14권3호
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    • pp.127-132
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    • 2014
  • Since 1970s, the metropolitan-cities in Korea constructed enormous capacities of apartment housings to settle the inferior housing conditions. However, from a stand point of children, the formality of the apartment housing is too tight and specialized to give children enough space to play in and the location and physical area of that is bad and insufficient either. In this study, progressive method for the playground is offered to improve the conditions of playground in apartment housings through the examinations of the utilization of the playground and the problems of that. As a result, three of items for the improvement of the playgrounds are suggested. First, re-interventions for the rules which prescribe the area of the playgrounds are needed. Second, the locations of the playgrounds should be based on the children's playing activities and parents' profitable apprehend. Third, the access to the playgrounds should be based on the children's conveniences. In order to perform these recommended items, objective POE data for the playgrounds through the systematic examinations are also needed in addition to the abilities of the planners.