• 제목/요약/키워드: Focus distance

검색결과 426건 처리시간 0.032초

The Effect of Distance of External Attentional Focus on the Performance of Balance Task in Upper Extremity

  • Roh, Jung-Suk
    • 한국전문물리치료학회지
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    • 제18권4호
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    • pp.51-59
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    • 2011
  • The purpose of this study was to investigate the effect of attentional focus and distance of external focus on the performance of balance task of upper extremity. Subjects (N=30) held a stick (2 m) and maintained it horizontally. All of the subjects performed balance task of upper extremity under four different attentional focus conditions: focus on hand (internal focus), marker at 10 cm inside of hand (external focus 1), marker at 10 cm outside of hand (external focus 2), marker at 20 cm outside of hand (external focus 3). The mean velocity of the bar (mm/s) and the muscle activity of biceps brachii (%RVC) were measured. They were decreased when the subjects focused on external focuses compared to internal focus and decreased as distance of attentional focus from body increased (p<.05). There were significant differences between groups (p<.05); internal focus-external focus 1, internal focus-external focus 2, internal focus-external focus 3, external focus 2-external focus 3. These results showed that external focus is more effective than internal focus in enhancing motor performance and focusing on more distant attentional focus results in enhanced motor performance promoting the utilization of more automatic control mechanisms.

곡률 변경 소자를 이용한 All In Focus (All in focus Camera vision system for Mobile Phone based on the Micro Diffractive Fresnel lens systems)

  • 지용석;김영섭
    • 반도체디스플레이기술학회지
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    • 제6권3호
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    • pp.65-70
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    • 2007
  • A method to focus the object in camera system by applying the Hill climb algorithm from optical lens moving device (VCM; Voice coil motor) is proposed. The focusing algorithm from VCM is focus on the object but in these criteria is a well-known drawback; the focus is good only at same distance objects but the focus is bad (blur image) at different distance objects because of the DOF (Depth of focus) or DOF (Depth of field) at the optical characteristic. Here, the new camera system that describes the Reflector of free curvature systems (or Diffractive Fresnel lens) and the partition of focusing window area is proposed. The method to improve the focus in all areas (different distance objects) is proposed by new optical system (discrete auto in-focus) using the Reflector of free curvature systems (or Diffractive Fresnel lens) and by applying the partition of all areas. The proposal is able to obtain good focus in all areas.

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Consumers' Channel Selection Behavior Based on Psychological Distance Cue: Regulatory-Focus as Moderator

  • Jungyeon Sung;Sangcheol Park
    • Asia pacific journal of information systems
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    • 제29권2호
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    • pp.248-267
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    • 2019
  • As merging online and offline channels into one single platform, individuals could easily and frequently switch between online and offline channels. In order for understanding such unique behaviors, this study attempts to explore why and how consumers choose their channels to search and purchase a product. We have drawn on multiple theories that have been used to explain individuals' judgment and decision making (i.e., construal level theory and regula-tory focus theory) in order to develop and tested two-way ANOVA based models of how both regulatory focus (e.g., promotion vs. prevention) and product types (e.g., experience goods vs. searching goods) including the psychological distance cue separately and jointly affect individuals' channel selection behavior (e.g., intention to use single channel vs. intention to use cross-channels). Our results have indicated that consumers with promotion-focus are more likely to use a single channel in experience goods rather than in searching goods when there exists the psychological cue. Based on our findings, the implication for both research and practice are discussed.

자기규제초점과 심리적 거리가 창업태도 및 창업의도에 미치는 영향 (The Effects of Regulatory Focus and Psychological Distance on Entrepreneurial Intention)

  • 하환호;변충규
    • 벤처창업연구
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    • 제11권2호
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    • pp.1-8
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    • 2016
  • 본 연구에서는 창업태도와 행동의도에 영향을 미치는 선행변수로 자기규제초점과 심리적 거리에 주목하였다. 자기규제초점은 향상초점과 예방초점으로 구분할 수 있다. 본 연구에서는 향상초점집단과 예방초점집단이 창업에 대한 심리적 거리에 따른 창업태도와 행동의도의 영향력을 이원변량분석을 통해 살펴보았다. 분석결과, 자기규제초점에 따라 창업태도와 행동의도에 차이가 나타났다. 즉, 예방초점집단보다는 향상초점집단에서 행동의도가 더 높은 것으로 나타났다. 심리적 거리에 따라 이들의 영향이 어떻게 달라지는지 살펴본 결과, 향상초점집단에서는 창업에 대해 심리적 거리가 멀 때보다는 가깝다고 느낄 때 창업태도와 창업의도가 높게 나타났다. 반면에 예방초점집단에서는 창업에 대해 가깝다고 느낄 때보다는 멀다고 느낄 때 창업태도와 행동의도가 더 높게 나타났다. 이러한 연구결과를 바탕으로 연구의 학문적 의의와 실무적 시사점 그리고 연구의 한계점을 제시하였다.

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디지털 입자 홀로그래피의 입자 초점 심도에 관한 연구 (A Study on Depth of Focus of Particle in Digital Particle Holography)

  • 양얀;강보선
    • 한국분무공학회지
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    • 제14권2호
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    • pp.77-83
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    • 2009
  • In this study, the effect of important parameters such as the pixel size and number of a CCD, the object distance, the wavelength of laser, and the particle diameter on the depth of focus in digital in-line particle holography were investigated. The depth of focus in several different cases was calculated using simulation holograms and detailed description of the depth of focus in digital particle holography was presented. The depth of focus is directly proportional to the object distance and the particle size. With the increase of the wavelength of laser, the depth of focus is decreased. The depth of focus is also inversely proportional to the pixel size and number of a CCD. Using the data of depth of focus from simulation holograms and a data-fitting software, we obtained the prediction equations of depth of focus for typical CCD cameras. Finally, the prediction equations of depth of focus in digital particle holography were verified by investigating real holograms of the calibration target in different cases and satisfied agreement between measured values and predicted values was confirmed.

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Analysis and Evaluation of Slanted-edge-based Modulation Transfer Function and Focus Measurements for Optimal Assembly of Imaging Modules in Gastrointestinal Endoscopy

  • Wonju Lee;Ki Young Shin;Dong-Goo Kang;Minhye Chang;Young Min Bae
    • Current Optics and Photonics
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    • 제7권4호
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    • pp.398-407
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    • 2023
  • We explored a method to evaluate imaging performance for the optimal assembly of an endoscopic miniature lens and a sensor constituting an imaging module at the distal end of gastrointestinal endoscopy. For the assembly of the imaging module, the image sensor was precisely located at the focal plane when collimated light passed through the endoscopic lens. As another method, the distance between the lens and sensor was adjusted to obtain the highest focus index from images measured the star chart of the International Organization for Standardization (ISO) standard at various positions. We analyzed the slanted-edge modulation transfer function (MTF), corresponding depth of field, and number of line pairs for MTF 50% and 20% at each working distance within the range of 5-100 mm for imaging modules assembled in different ways. Assembly conditions of the imaging module with better MTF performance were defined for each working distance range of 5-30 mm and 30-100 mm, respectively. In addition to the MTF performance, the focus index of each assembled module was also compared. In summary, we examined the performance of imaging modules assembled with different methods within the suggested working distance and tried to establish the optimal assembly protocol.

구매시기와 소비시기 간의 시간 간격이 소비자 선택에 미치는 영향 (The Effects of Temporal Distance between Purchase and Consumption on Consumer Choice)

  • 강현모;민동원
    • 한국경영과학회지
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    • 제35권4호
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    • pp.1-16
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    • 2010
  • In consumption environment, the time interval is frequently found between purchase and consumption. The objective of this study is to determine how consumers' purchase intentions can be influenced by this type of temporal distance. Construal level theory holds that the 'distant future situation' tend to be construed on a higher level than the 'near future situation.' Accordingly, when considering the consumption in the near future, consumers tend to be more likely to focus on the feasibility of the alternatives than on desirability. Conversely, when considering the consumption in the distant future, they are more likely to focus on the desirability of the alternatives than on feasibility. Along with the previous literature, the current study investigates the effects of temporal distance between purchase and consumption on consumer choice. Moreover, we aim to determine under which conditions these effects pertain. To test our hypotheses, we conducted a 2(temporal distance:near future vs. distant future) x 2(alternative type:high desirability, low feasibility vs. low desirability, high feasibility) x 3(additional offering:no gift, free coffee coupon, free mini book) between subjects design. The results show that the main effects of temporal distance and additional offering are significant. The 2 way interaction between temporal distance and additional offerings is also significant. Specifically, the purchase intention differentiation from additional offering tends to be larger at shorter temporal distances (near future) than at long ones (distant future).

Numerical Analysis of Working Distance of Square-shaped Beam Homogenizer for Laser Shock Peening

  • Kim, Taeshin;Hwang, Seungjin;Hong, Kyung Hee;Yu, Tae Jun
    • Current Optics and Photonics
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    • 제1권3호
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    • pp.221-227
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    • 2017
  • To apply a square-shaped beam homogenizer to laser shock peening, it should be designed with a long working distance and by considering metal targets with various shapes and textures. For long working distances, a square-shaped beam homogenizer with a long depth of focus is required. In the range of working distance, the laser beam is required to have not only high efficiency but high uniformity, in other words, a good peening quality is guaranteed. In this study, we defined this range as the working distance for laser shock peening. We have simulated the effect of some parameters on the working distance. The parameters include the focal length of the condenser lens, pitch size of the array lens, and plasma threshold of the metal. The simulation was performed through numerical analysis by considering the diffraction effect.

초점정보를 이용한 패턴간의 상대적 깊이 추정알고리즘 개발 (A Relative Depth Estimation Algorithm Using Focus Measure)

  • 정지석;이대종;신용녀;전명근
    • 한국지능시스템학회논문지
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    • 제23권6호
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    • pp.527-532
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    • 2013
  • 깊이 추정은 로봇 비전, 3차원 영상, 모션 제어를 위해 사용되는 매우 중요한 인자이다. 깊이 추정은 렌즈와 물체 사이의 거리를 변화시켜가면서 취득된 일련의 영상에서 계산된 초점 정보에 기반을 둔다. 본 논문에서는 다양한 초점정보를 이용한 패턴간의 상대적 깊이 추정 알고리즘을 제안한다. 제안된 방법은 거리별로 취득된 영상의 초점값 정보를 이용하여 구현하였으며, 깊이는 두 패턴의 상대적 거리를 고려함으로써 추정하였다. 다양한 영상정보를 이용하여 깊이 추정을 수행한 결과 효과적인 추정이 가능함을 알 수 있었다.

어닐링 알고리즘을 이용한 CCD 카메라 초점 제어 (Focus Control for CCD Camera using Annealing Algorithm)

  • 이관용;임신영;조성원
    • 한국지능시스템학회논문지
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    • 제10권5호
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    • pp.459-465
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    • 2000
  • 본 논문에서는 CCD 카메라에서 나오는 NTSC 신호를 분석하여 근거리에서 초점을 맞출 수 있도록 렌즈의 동작을 제어하는 방법을 제안한다. 카메라와 물체의 거리가 약 1미터 이하로 가까워지면 자동 초점 기능을 갖춘 카메라는 영상의 전체적인 초점보다는 가장 근접한 미세 부분을 기준으로 초점을 맞추어서 영상을 획득한다. 이러한 문제를 해결하기 위해, 어닐링 알고리즘을 이용하여 CCD 카메라 렌즈에 내장된 모터를 영상의 전체적인 신호에 따라 제어하여 근거리에서 처리대상에 가장 적합한 영상을 획득하는 방법을 제안한다. 이러한 CCD 카메라 초점 제어 기술은 눈의 홍채를 이용한 인식 시스템에서 사용될 목적으로 개발되었다.

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