• 제목/요약/키워드: Segment flexibility

검색결과 35건 처리시간 0.024초

FlexRay 프로토콜의 동적 구간에서의 잔여 미니 슬롯 확률 분포 분석 (Analysis of Empty Minislot Distribution in the FlexRay Dynamic Segment)

  • 김봉준;박기진
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2008년도 추계학술발표대회
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    • pp.936-939
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    • 2008
  • 차량 내부 네트워크(In-Vehicle Network)에 많은 관심이 고조되는 가운데 Time-Triggered 와 Event-Triggered 패러다임의 장점을 모두 갖춘 하이브리드(Hybrid) 프로토콜인 FlexRay 가 최근 들어 많은 자동차 분야 업체들로부터 주목 받으면서 이에 대한 다양한 성능 분석 시도가 이루어지고 있다. 하지만 FlexRay 프로토콜의 메시지 전송의 유연성(Flexibility)으로 인해 정확한 성능 분석에 많은 어려움이 있다. 이에 본 논문에서는 다양한 길이의 메시지를 고려한 동적 구간 분석 모델을 제안하였고, 이를 바탕으로 잔여 미니 슬롯 확률 분포(Empty Minislot Distribution)를 도출하였으며 FlexRay 메시지 셋(Set)를 이용한 실험을 통하여 특정 길이의 동적 구간에서 미니 슬롯 개수에 따른 잔여 미니 슬롯 발생확률 값의 변화를 확인하였다.

스쿼시 백핸드 드라이브 동작시 상지 분절의 운동학적 변인 분석 (The Kinematic Analysis of the Upper Extremity during Backhand Stroke in Squash)

  • 안용환;류지선;류호영;소재무;임영태
    • 한국운동역학회지
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    • 제17권2호
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    • pp.145-156
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    • 2007
  • The purposes of this study were to investigate kinematic parameters of racket head and upper extremities during squash back hand stroke and to provide quantitative data to the players. Five Korean elite male players were used as subjects in this study. To find out the swing motion of the players, the land-markers were attached to the segments of upper limb and 3-D motion analysis was performed. Orientation angles were also computed for angular movement of each segment. The results were as follows. 1) the average time of the back hand swing (downswing + follow-through) was 0.39s (0.24 s + 0.15 s). 2) for each event, the average racket velocity at impact was 11.17m/s and the velocity at the end of swing was 8.03m/s, which was the fastest swing speed after impact. Also, for each phase, 5.10m/s was found in down swing but 7.68m/s was found in follow-through. Racket swing speed was fastest after the impact but the swing speed was reduced in the follow-through phase. 3) in records of average of joints angle, shoulder angle was defined as the relative angle to the body. 1.04rad was found at end of back swing, 1.75rad at impact and it changes to 2.35 rad at the end of swing. Elbow angle was defined as the relative angle of forearm to upper arm. 1.73rad was found at top of backswing, 2.79rad at impact, and the angle was changed to 2.55rad at end of swing. Wrist angle was defined as the relative angle of hand to forearm. 2.48rad was found at top of backswing, 2.86rad at impact, and the angle changes to 1.96rad at end of swing. As a result, if the ball is to fly in the fastest speed, the body has to move in the order of trunk, shoulder, elbow and wrist (from proximal segment to distal segment). Thus, the flexibility of the wrist can be very important factor to increase ball speed as the last action of strong impact. In conclusion, the movement in order of the shoulder, elbow and the wrist decided the racket head speed and the standard deviations were increased as the motion was transferred from proximal to the distal segment due to the personal difference of swing arc. In particular, the use of wrist (snap) may change the output dramatically. Therefore, it was concluded that the flexible wrist movement in squash was very important factor to determine the direction and spin of the ball.

Polyorganosiloxane 변성 폴리우레탄의 유변 특성 (Rheological Properties of Polyurethane Modified with Polyorganosiloxane)

  • 한정우;한미선;이상문;박태석;강두환
    • 폴리머
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    • 제26권5호
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    • pp.607-614
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    • 2002
  • 폴리우레탄 (ITPU) 실란트의 내후성 및 변색성 개선을 위하여 polyorganosiloxane변성 폴리우레탄 (UMPS)을 합성하고 이들의 유변 특성을 고찰하였다. 폴리우레탄에 도입되는 polyorgano-siloxane block (HBPS)의 함량을 증가시키면 주사슬의 HBPS 부분의 segregation에 의하여 ITPU//HBPS의 비가 70/30에서 점도가 가장 높음을 알 수 있으나 HBPS의 함량을 더 증가시키면 HHPS 주사슬의 유연성에 의하여 점도가 다시 감소함을 확인할 수 있었다. 또한 UMPS는 기존의 폴리우레탄에 비하여 전단속도, 온도, 습도 및 경화 온도의 점도 의존성이 높음을 알 수 있었다. 아울러 MPS에 커플링제를 첨가할 경우 말단 Si(O$CH_3$)$_3$의 도입으로 경화가 촉진되나 이들의 함량이 0.5 wt% 이상 되면 말단 NCO기의 감소에 따라 경화가 늦어지며 그 결과, 전도가 급격히 감소함을 알수 있었다.

첨단산업과 패션산업의 경쟁전략적 유사성에 관한 연구 : 일본 Y사의 사례 연구

  • 김양희
    • 기술경영경제학회:학술대회논문집
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    • 기술경영경제학회 1997년도 제11회 하계학술발표회 논문집
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    • pp.224-243
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    • 1997
  • The study examines the similarities of competitive strategy between fashion industry and high-tech industry through a case study of a Japanese maker. From the study, some implications are drawn for the Korean fashion industry. It is hoped that this, will help towards establishing a suitable competitive strategy for firms in this industry. In the fashion industry, the product life cycle is so short as to prompt a new product obsolete too quickly, and the extent of product differentiation is remarkably extensive compared to any other industry. Generally speaking, firms in this industry focus more of their resources on product development and marketing rattler than on production and they attempt to maneuver the speed when they are required to enhance their competitive edge. This is enabled through being, as one might expect, information- and technology- intensive as are high-tech industries. In this sense, that of the competitive strategy of a firm in fashion industry to be similar to high-tech industry. The Japanese firm Y has transformed itself a leading firm in fashion uniform segment. The firm could achieve this status by integrating each function needed for creating customer*s value, that is, product development, production and marketing within one Quick Response System. For this purpose, Y introduced a bundle of high-tech communication systems such as SPD, SDS, ATOM, NICS and so on. In this sense it can be said that Y was aware of what sort of competitive strategy was required in the industry. Implications for Korean firms is that, first, the magnitude of understanding the industry specific factors in establishing competitive strategy in the fashion industry, are speed, flexibility and systematic integration supported by high technology which are characteristic of high-tech industries. Secondly, as can be seen in the fact that Y emphasized logistics in its technological transformation, the significance of logistics control is a key to manipulating speed and flexibility in the industry. To sum up, those who have insight into above findings will be likely to keep their competitiveness in the industry not only in the Korean market but also in global market in the near future.

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모형실험에 의한 조립식 격자 옹벽의 거동 특성 (The Behavior Characteristics of Segmental Crib Retaining Wall by Model Test)

  • 김상수;신방웅;김용언;이재영;변동건
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 1999년도 가을 학술발표회 논문집
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    • pp.449-456
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    • 1999
  • The concrete wall is the most useful of retaining structure which can obtain the engineering stability, but has problems that is not friendly with nature environment in a fine view, such as poor rear drainage, and shrinkage crack by temperature difference, etc. Because of this problems, the research for a segmental crib retaining wall has been performed. A segmental crib retaining wall is quickly and easily erected because is possible to be erected as the individual members, and is not sensitive to differential settlement and earthquakes. Also, it shows effective drainage and has a friendly advantage with nature environment because of being able to be planted with vines and shrubs in retaining walls The design of crib retaining walls has traditionally been based on classical soil mechanics theories. These theories, originally derived by Rankine(1857) and Coulomb(1776), assume that the wall acts as a rigid body. This assumption results in failure being predicted by either monolithic overturning or base sliding mechanisms. However, the wall consists of individual members which have been created a three dimensional grid. This grid confines an fill mass which becomes part of the wall. The filled wall resists the earth pressure with the same mechanism of classical gravity walls. Because of the flexibility of the individual segment, it allows relative movement between the individual members within the wall. The three dimensional flexible grid leads to stress redistribution when the wall is subjected to external or fill loads. Due to the flexibility and the stress redistribution, the failure of segmental crib wall consists of not only overturing and base sliding but the local deformation and the failure between the segmental members. It has been researched in the field that due to this flexibility and load redistribution, serviceability failure of segmental crib walls is unlikely to be due to overturning or base sliding. Therefore, in this study, the relative displacement appearance of retaining wall due to variation of inclination is measured to examine this behavior characteristics. Also, the behavior characteristics of retaining walls by surcharge load, and location of acting point of retaining wall rear, and the displacement characteristics and deflections are estimated about the existence and nonexistence of Rear Stretcher performing an role in transmitting earth pressure of Header and Stretcher organizing retaining walls. This research focuses on the characteristics due to the behavior of retaining walls. This research focuses on the characteristics due to the behavior of retaining walls.

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ATB의 전처리 프로그램 개발 (Development of a Preprocessor Program for Articulated Total Body)

  • 이동재;손권;최경현;전규남
    • 한국자동차공학회논문집
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    • 제10권5호
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    • pp.214-222
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    • 2002
  • Computer simulations are widely used to analyze passenger safety in simulated traffic accidents. ATB, Articulated Total Body, is a computer simulation model developed to predict gross human body response to such dynamic environments as vehicle crashes and pilot ejections. ATB, whose code is open, has high flexibility and application capability that users can easily insert defined modules and functions. ATB is, however, inconvenient as it was coded in FORTRAN and it needs a formated input file. Moreover, it takes much time to make input files and to modify coding errors. This study aims to increase user friendliness by adding a preprocessor program, WINATB(WINdows ATB), to the conventional ATB. WINATB, programmed in Visual C++ and OpenGL, uses ATB IV as a dynamic solver. The preprocessor helps users prepare input files through graphic interface and dialog box. An additional postprocessor makes the graphical presentation of simulated results. In these case of the frontal crash, the rear impact and the side impact, the simulation results obtained by WINATB and MADYMO(MAthematical Dynamic Model) are compared to validate the effectiveness of WINAIB.

테니스 양손 백핸드 스트로크 방법에 따른 어깨와 힙의 회전운동 변화 (Change in Rotational Motion of the Shoulder and Hip According to the Method Used for a 2-Handed Backhand Stroke in Tennis)

  • 강상학
    • 한국운동역학회지
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    • 제21권1호
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    • pp.39-46
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    • 2011
  • The purpose of this study was to examine differences between players who bend the left elbow and those who stretch it during the forward swing from BST to BC in a 2-handed backhand stroke among outstanding high school tennis players, and to assess the detailed 3D rotational kinematic characteristics of the shoulder and the hip. Statistically significant differences were observed between groups in the longitudinal axis rotation angle of the shoulder and the angle between the shoulder and the arm at BST, and in the side to side movement of the shoulder, the up and down movement of the hip, the side tilt angular velocity of the shoulder, the side tilt angular velocity of the hip, and the front tilt angular velocity of the hip at BC. The difference in the longitudinal axis rotation angle of the shoulder between the 2 groups suggests a difference in the flexibility of the joint in the shoulder arm racquet system. The longitudinal axis rotation angular velocity of the shoulder reached its peak at 75 % of the duration of the analyzed segment and then decreased little by little until BC. This time is considered the stage for increasing the angular velocity of the upper arm, the forearm, the hand and then the racquet, which are more distal segments than the shoulder.

고정성 분할 브릿지의 연결 어태치먼트 (Connect Attachment of Fixed Segmented Bridge)

  • 김남중
    • 대한치과기공학회지
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    • 제24권1호
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    • pp.127-138
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    • 2002
  • There are some cases that dental prosthesis does not operate as properly as expected in oral mouth. The reasons are such as a distortion of the mandibular, a fault of impression taking system or an extrusion of remaining teeth. One of dental prostheses to consider in the situations is the attachment which connects segment bridge. Active discussions are managed on theoretical side of this field but few on clinical side of it, which must be considered first. Accordingly I'd like to suggest a theoretical background for connect attachment of fixed segmented bridge. 1. As a bridge gets longer, burden on dental ligament is increased and the hardness of a bridge is lessened. 2. The flexibility of a bridge increases in ratio to 3 multiplication of the length and decreases in ratio to 3 multiplication of the width of occlusal surface and base of pontic. 3. Precision rest is needed to cope with the shake of teeth and the difference of axis direction among abutments. 4. Female part of the precision rest should be on middle abutment distal and male one on mesial of pontic. 5. Segmented attachment can be efficiently used to cope with long span bridgework and also in case that one piece casting can't be done because of slant of abutment.

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기하학적 동적 외곽선 모델을 이용한 X-ray 단층촬영영상의 영상추출 (Segmentation of Computed Tomography using The Geometric Active Contour Model)

  • 장동표;김선일
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1997년도 추계학술대회
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    • pp.541-545
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    • 1997
  • This paper presents a modified geometric active contour model or edge detection and segmentation of computed tomography(CT) scan images. The method is based on the level setup approach developed by Osher and Sethian and the modeling of propagation fronts with curvature dependent speeds by Malladi. Based on above algorithms, the geometric active contour is obtained through a particular level set of hypersurface lowing along its gradient force and curvature force. This technique retains the attractive feature which is topological and geometric flexibility of the contour in recovering objects with complex shapes and unknown topologies. But there are limitations in this algorithm which are being not able to separate the object with weak difference from neighbor object. So we use speed limitation filter to overcome those problems. We apply a 2D model to various synthetic cases and the three cases of real CT scan images in order to segment objects with complicated shapes and topologies. From the results, the presented model confirms that it attracts very naturally and efficiently to the desired feature of CT scan images.

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Brand Revitalization by Strategic Repositioning: A Case Study of Korando Sports

  • Shin, Youngsik;Cha, Kyoung Cheon
    • Asia Marketing Journal
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    • 제14권4호
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    • pp.1-22
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    • 2013
  • A growing gap between market needs and the capabilities of the enterprise prompts repositioning (Corstjens and Dolye 1989). This article examines the strategic repositioning of 'Korando Sports' undertaken by SYMC throughout the period from Jan. 2012 to Jun. 2012, to boost sales volume and market share by entering market of active-lifestyle consumers currently occupied by SUVs. SYMC's experience indicates that it is essential to close the gap between the market needs and the ability of the enterprise to make a shift to new consumer segment with a new positioning. The successful repositioning framework(Ryan et al. 2007) were employed in this paper. This framework is comprised of six elements: core strategic values, strategic flexibility/learning capabilities, customer awareness and sensitivity, external orientation, management commitment, and belief in the product and brand. The evaluation based on the successful framework also confirms that 'Korando Sports' case meets all the requirements of the successful strategic repositioning. This paper provides some of the managerial implications with aim of assisting executives in identifying strategic repositioning opportunities. Primarily, the 'Korando Sports' case affirms the repositioning as a viable strategy and indicates that repositioning is a feasible means for strategic change. Second, this case shows the influence of a target consumer and SYMC's repositioning to follow consumer preference for a particular attribute. Moreover, we can understand how a product formerly considered weak in attributes can enjoy benefits in other segments with the same attributes.

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