• Title/Summary/Keyword: Maximum object size

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Estimation of maximum object size satisfying mean response time constraint in web service environment (웹 서비스 환경에서 평균 응답 시간의 제약조건을 만족하는 최대 객체 크기의 추정)

  • Yong-Jin Lee
    • Journal of Internet of Things and Convergence
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    • v.9 no.3
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    • pp.1-6
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    • 2023
  • One of the economical ways to satisfy the quality of service desired by the user in a web service environment is to adjust the size of the object. To this end, this study finds the maximum size of objects that satisfy this constraint when the mean response time is given below an arbitrary threshold for quality of service. It can be inferred that in the steady state of system, the mean response time in the deterministic model by using the round-robin will be the same as that of the queueing model following the general distribution. Based on this, analytical formulas and procedures for finding the maximum object size are obtained. As a service distribution of web traffic, the Pareto distribution is appropriate, so the maximum object size is computed by applying the M/G(Pareto)/1 model and the M/G/1/PS model using exponential distribution as computational experience. Performance evaluation through numerical calculation shows that as the shape parameter in the Pareto distribution increases, the M/G(Pareto)/1 model and M/G/1/PS model have the same maximum object size. The results of this study can be used to environments where objects can be sized for economical web service control.

Resolution analysis of Fourier Hologram using integral imaging

  • Chen, Ni;Park, Jae-Hyeung;Kim, Nam
    • Proceedings of the Optical Society of Korea Conference
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    • 2009.10a
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    • pp.331-332
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    • 2009
  • We present an analysis on the quality factors of the Fourier hologram generated from multiple orthographic view images of three-dimensional object. In the analysis, we analyze both the maximum size of the reconstructed object and its spatial resolution. For the maximum size of the reconstruction, we found that the main factor is the orthographic projection angle interval. Too large projection angle interval causes overlapping in the reconstruction space domain. For the spatial resolution, there are three factors, i.e. the capturing lens array pitch which determines the spatial sampling rate of the original three-dimensional objects, the maximum orthographic projection angle, and the spatial frequency bandwidth of the object. The dominant factor is determined by the relationship between those three factors.

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Boundary Line Extract for Moving Object Tracking (이동 물체 추적을 위한 경계선 추출)

  • Kim, Tea-Sik;Lee, Ju-Shin
    • Journal of the Korean Institute of Telematics and Electronics T
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    • v.35T no.2
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    • pp.28-34
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    • 1998
  • In this paper, I'd like to make a suggestion for boundary line detect algorithm which is used 3-D image processing system in order to track moving object. Through this study, more than anything else, difference image method was adopted to detect moving object in input image. To detect moving object, I made use of detect windows constructed by 4's predictive areas and object area for the purpose of reducing processing time and its size was determined by the size of moving object and prediction parameter directed center position. And also, tracking camera was movable toward the direction of X, Y by DC motor. As a conclusion of the study proposed algorithm, I found out the following results that tracking error was less than 6% of total moving object size and maximum tracking time 2 seconds by toy-car simulation.

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Implementation of Motion Detection of Human Under Fixed Video Camera (고정 카메라 환경하에서 사람의 움직임 검출 알고리즘의 구현)

  • 한희일
    • Proceedings of the IEEK Conference
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    • 2000.06d
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    • pp.202-205
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    • 2000
  • In this paper we propose an algorithm that detects, tracks a moving object, and classify whether it is human from the video clip captured under the fixed video camera. It detects the outline of the moving object by finding out the local maximum points of the modulus image, which is the magnitude of the motion vectors. It also estimates the size and the center of the moving object. When the object is detected, the algorithm discriminates whether it is human by segmenting the face. It is segmented by searching the elliptic shape using Hough transform and grouping the skin color region within the elliptic shape.

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The Effects of Object Size and Reaching Distance on Upper Extremity Movement (물체 크기와 뻗기 거리가 상지 움직임에 미치는 영향)

  • Bae, Su-Young;Kim, Tae-Hoon
    • The Journal of Korean society of community based occupational therapy
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    • v.10 no.1
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    • pp.51-61
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    • 2020
  • Objectives : The purpose of this study is to investigate the effect of object size and reaching distance on kinematic factors of the upper limb while performing arm reaching for normal subjects. Methods : The subjects of this study were 30 university students who were in D university in Busan, and the measuring tool was CMS-70P(Zebris Medizintechnik Gmbh, Germany), a three-dimensional motion analyzer. The task had six conditions. The average velocity of motion, average acceleration, maximum velocity, and the velocity definite number of movements were measured according to changes in object size(2cm, 10cm) and reaching distance(15%, 37.5%, 60%) when they performed arm reaching. The general characteristics of the subject were technical statistics. One-way ANOVA measurement was used to compare variables when the arm reaching task was performed from two object sizes to three reaching distance, and the post-test was conducted with Tukey test. In addition, an independent t-test was used to analyze the kinematic differences according to the two object sizes at three reaching distances. A two-way ANOVA measurement (3×2 Two-way ANOVA measurement) was performed to identify the interaction of the reaching distance(15%, 37.5%, 60%) and the object size(2cm, 10cm). The statistical significance level α was set to .05. Results : When the size of the object increased, the velocity and maximum velocity also increased, but the definite number of velocity decreased. When the reaching distance increased, the velocity and maximum velocity increased, whereas the definite number of velocity decreased. Conclusion : The clinical significance of this study could be utilized as the baseline data for grading object size and reaching distances when the reaching training is implemented for patients whose central nervous system was damaged.

Realtime Object Region Detection Robust to Vehicle Headlight (차량의 헤드라이트에 강인한 실시간 객체 영역 검출)

  • Yeon, Sungho;Kim, Jaemin
    • Journal of Korea Multimedia Society
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    • v.18 no.2
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    • pp.138-148
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    • 2015
  • Object detection methods based on background learning are widely used in video surveillance. However, when a car runs with headlights on, these methods are likely to detect the car region and the area illuminated by the headlights as one connected change region. This paper describes a method of separating the car region from the area illuminated by the headlights. First, we detect change regions with a background learning method, and extract blobs, connected components in the detected change region. If a blob is larger than the maximum object size, we extract candidate object regions from the blob by clustering the intensity histogram of the frame difference between the mean of background images and an input image. Finally, we compute the similarity between the mean of background images and the input image within each candidate region and select a candidate region with weak similarity as an object region.

A Multiple Vehicle Object Detection Algorithm Using Feature Point Matching (특징점 매칭을 이용한 다중 차량 객체 검출 알고리즘)

  • Lee, Kyung-Min;Lin, Chi-Ho
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.17 no.1
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    • pp.123-128
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    • 2018
  • In this paper, we propose a multi-vehicle object detection algorithm using feature point matching that tracks efficient vehicle objects. The proposed algorithm extracts the feature points of the vehicle using the FAST algorithm for efficient vehicle object tracking. And True if the feature points are included in the image segmented into the 5X5 region. If the feature point is not included, it is processed as False and the corresponding area is blacked to remove unnecessary object information excluding the vehicle object. Then, the post processed area is set as the maximum search window size of the vehicle. And A minimum search window using the outermost feature points of the vehicle is set. By using the set search window, we compensate the disadvantages of the search window size of mean-shift algorithm and track vehicle object. In order to evaluate the performance of the proposed method, SIFT and SURF algorithms are compared and tested. The result is about four times faster than the SIFT algorithm. And it has the advantage of detecting more efficiently than the process of SUFR algorithm.

Advanced Design of Birdcage RF Coil for Various Absorption Regions at 3T MRI System

  • Lee, Jung-Woo;Choe, Bo-Young;Choi, Chi-Bong;Huh, Soon-Nyoung
    • Journal of the Korean Magnetic Resonance Society
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    • v.9 no.1
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    • pp.48-60
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    • 2005
  • Purpose: The purpose of this study was to design and build an optimized birdcage resonator configuration with a low pass filter, which would facilitate the acquisition of high-resolution 3D-image of small animals at 3T MRI system. Methods and Materials: The birdcage resonator with 12-element structures was built, in order to ensure B1 homogeneity over the image volume and maximum filling factor, and hence to maximize the signal to noise ratio (SNR) and resolution of the 3-dimensional images. The diameter and length of each element of a birdcage resonator were as follows: (1) diameter 13 cm, length 22 cm, (2) diameter 15 cm, length 22 cm, (3) diameter 17 cm, length 25 cm. Spin echo pulse sequence and fast spin echo pulse sequence were employed in obtaining MR images. The quality of the manufactured birdcage resonators wes evaluated on the basis of the return loss following matching and tuning process. Results: The experimental MR image of phantoms by the various manufactured birdcage resonators were obtained to compare the SNR in accordance with the size of objects. The size of an object to that of coil was identified by parameters that were estimated from the image of a phantom. First, the diameter of the birdcage resonator was 15cm, and the ratio of the tangerine to the birdcage resonator accounted for approximately 27%. The Q factor was 53.2 and the SNR was 150.7. Second, at the same birdcage resonator, the ratio of the orange was approximately 53%. The SNR and the Q parameter was 212.8 and 91.2, respectively. Conclusion: The present study demonstrated that if birdcage resonators have the same forms, SNR could be different depending on the size of an object, especially when the size of an object to that of coil is approximately 40~80%, the former is bigger than the latter. Therefore, when the size of an object to be observed is smaller than that of coil, the coil should be manufactured in accordance with the size of an object in order to obtain much more excellent images.

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Laser Head Design and Heat Transfer Analysis for 3D Patterning (3차원 패터닝을 위한 레이저 헤드설계 및 열해석)

  • Ye, Kang-Hyun;Choi, Hae-Woon
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.15 no.4
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    • pp.46-50
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    • 2016
  • A laser head was designed for micro-scale patterning and joining applications. The target feature size of the pattern was $100{\mu}m$, and optics were designed to perform the target. Two singlet lenses were combined to minimize the chromatic aberration, and the geometry of the lenses was calculated by using the raytracing method with a commercial software program. As a restriction of lens design, the focal length was set at 100mm, and the maximum diameter of the lens or beam size was limited to 10mm for the assembly in the limited cage size. The maximum temperatures were calculated to be $1367^{\circ}C$, $1508^{\circ}C$, and $1905^{\circ}C$ for 10, 12, and 15 Watts of power, respectively. A specially designed laser head was used to compensate for the distance between the object and the lens. The detailed design mechanism and 3D data were presented. The optics design and detailed performance of the lens were analyzed by using MTF and spot diagram calculation.

Optical System Design for Thermal Target Recognition by Spiral Scanning [TRSS]

  • Kim, Jai-Soon;Yoon, Jin-Kyung;Lee, Ho-Chan;Lee, Jai-Hyung;Kim, Hye-Kyung;Lee, Seung-Churl;Ahn, Keun-Ok
    • Journal of the Optical Society of Korea
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    • v.8 no.4
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    • pp.174-181
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    • 2004
  • Various kinds of systems, that can do target recognition and position detection simultaneously by using infrared sensing detectors, have been developed. In this paper, the detection system TRSS (Thermal target Recognition by Spiral Scanning) adopts linear array shaped uncooled IR detector and uses spiral type fast scanning method for relative position detection of target objects, which radiate an IR region wavelength spectrum. It can detect thermal energy radiating from a 9 m-size target object as far as 200 m distance. And the maximum field of a detector is fully filled with the same size of target object at the minimum approaching distance 50 m. We investigate two types of lens systems. One is a singlet lens and the other is a doublet lens system. Every system includes one aspheric surface and free positioned aperture stop. Many designs of F/1.5 system with ${\pm}5.2^{\circ}$ field at the Efl=20, 30 mm conditions for single element and double elements lens system respectively are compared in their resolution performance [MTF] according to the aspheric surface and stop position changing on their optimization process. Optimum design is established including mechanical boundary conditions and manufacturing considerations.