• Title/Summary/Keyword: Support Boundary

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A ProstateSegmentationofTRUS ImageusingSupport VectorsandSnake-likeContour (서포트 벡터와 뱀형상 윤곽선을 이용한 TRUS 영상의 전립선 분할)

  • Park, Jae Heung;Se, Yeong Geon
    • Journal of the Korea Society of Computer and Information
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    • v.17 no.12
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    • pp.101-109
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    • 2012
  • In many diagnostic and treatment procedures for prostate disease accurate detection of prostate boundaries in transrectal ultrasound(TRUS) images is required. This is a challenging and difficult task due to weak prostate boundaries, speckle noise and the short range of gray levels. In this paper a method for automatic prostate segmentation inTRUS images using support vectors and snake-like contour is presented. This method involves preprocessing, extracting Gabor feature, training, and prostate segmentation. Gabor filter bank for extracting the texture features has been implemented. A support vector machine(SVM) for training step has been used to get each feature of prostate and nonprostate. The boundary of prostate is extracted by the snake-like contour algorithm. The results showed that this new algorithm extracted the prostate boundary with less than 9.3% relative to boundary provided manually by experts.

Nonlinear boundary parameter identification of bridges based on temperature-induced strains

  • Wang, Zuo-Cai;Zha, Guo-Peng;Ren, Wei-Xin;Hu, Ke;Yang, Hao
    • Structural Engineering and Mechanics
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    • v.68 no.5
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    • pp.563-573
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    • 2018
  • Temperature-induced responses, such as strains and displacements, are related to the boundary conditions. Therefore, it is required to determine the boundary conditions to establish a reliable bridge model for temperature-induced responses analysis. Particularly, bridge bearings usually present nonlinear behavior with an increase in load, and the nonlinear boundary conditions cause significant effect on temperature-induced responses. In this paper, the bridge nonlinear boundary conditions were simulated as bilinear translational or rotational springs, and the boundary parameters of the bilinear springs were identified based on the measured temperature-induced responses. First of all, the temperature-induced responses of a simply support beam with nonlinear translational and rotational springs subjected to various temperature loads were analyzed. The simulated temperature-induced strains and displacements were assumed as measured data. To identify the nonlinear translational and rotational boundary parameters of the bridge, the objective function based on the temperature-induced responses is then created, and the nonlinear boundary parameters were further identified by using the nonlinear least squares optimization algorithm. Then, a beam structure with nonlinear translational and rotational springs was simulated as a numerical example, and the nonlinear boundary parameters were identified based on the proposed method. The numerical results show that the proposed method can effectively identify the parameters of the nonlinear boundary conditions. Finally, the boundary parameters of a real arch bridge were identified based on the measured strain data and the proposed method. Since the bearings of the real bridge do not perform nonlinear behavior, only the linear boundary parameters of the bridge model were identified. Based on the bridge model and the identified boundary conditions, the temperature-induced strains were recalculated to compare with the measured strain data. The recalculated temperature-induced strains are in a good agreement with the real measured data.

In-network Distributed Event Boundary Computation in Wireless Sensor Networks: Challenges, State of the art and Future Directions

  • Jabeen, Farhana;Nawaz, Sarfraz
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.11
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    • pp.2804-2823
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    • 2013
  • Wireless sensor network (WSN) is a promising technology for monitoring physical phenomena at fine-grained spatial and temporal resolution. However, the typical approach of sending each sensed measurement out of the network for detailed spatial analysis of transient physical phenomena may not be an efficient or scalable solution. This paper focuses on in-network physical phenomena detection schemes, particularly the distributed computation of the boundary of physical phenomena (i.e. event), to support energy efficient spatial analysis in wireless sensor networks. In-network processing approach reduces the amount of network traffic and thus achieves network scalability and lifetime longevity. This study investigates the recent advances in distributed event detection based on in-network processing and includes a concise comparison of various existing schemes. These boundary detection schemes identify not only those sensor nodes that lie on the boundary of the physical phenomena but also the interior nodes. This constitutes an event geometry which is a basic building block of many spatial queries. In this paper, we introduce the challenges and opportunities for research in the field of in-network distributed event geometry boundary detection as well as illustrate the current status of research in this field. We also present new areas where the event geometry boundary detection can be of significant importance.

A TRUS Prostate Segmentation using Gabor Texture Features and Snake-like Contour

  • Kim, Sung Gyun;Seo, Yeong Geon
    • Journal of Information Processing Systems
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    • v.9 no.1
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    • pp.103-116
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    • 2013
  • Prostate cancer is one of the most frequent cancers in men and is a major cause of mortality in the most of countries. In many diagnostic and treatment procedures for prostate disease accurate detection of prostate boundaries in transrectal ultrasound(TRUS) images is required. This is a challenging and difficult task due to weak prostate boundaries, speckle noise and the short range of gray levels. In this paper a method for automatic prostate segmentation in TRUS images using Gabor feature extraction and snake-like contour is presented. This method involves preprocessing, extracting Gabor feature, training, and prostate segmentation. The speckle reduction for preprocessing step has been achieved by using stick filter and top-hat transform has been implemented for smoothing the contour. A Gabor filter bank for extraction of rotation-invariant texture features has been implemented. A support vector machine(SVM) for training step has been used to get each feature of prostate and nonprostate. Finally, the boundary of prostate is extracted by the snake-like contour algorithm. A number of experiments are conducted to validate this method and results showed that this new algorithm extracted the prostate boundary with less than 10.2% of the accuracy which is relative to boundary provided manually by experts.

Application of shear deformation theory for two dimensional electro-elastic analysis of a FGP cylinder

  • Arefi, M.;Rahimi, G.H.
    • Smart Structures and Systems
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    • v.13 no.1
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    • pp.1-24
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    • 2014
  • The present study deals with two dimensional electro-elastic analysis of a functionally graded piezoelectric (FGP) cylinder under internal pressure. Energy method and first order shear deformation theory (FSDT) are employed for this purpose. All mechanical and electrical properties except Poisson ratio are considered as a power function along the radial direction. The cylinder is subjected to uniform internal pressure. By supposing two dimensional displacement and electric potential fields along the radial and axial direction, the governing differential equations can be derived in terms of unknown electrical and mechanical functions. Homogeneous solution can be obtained by imposing the appropriate mechanical and electrical boundary conditions. This proposed solution has capability to solve the cylinder structure with arbitrary boundary conditions. The previous solutions have been proposed for the problem with simple boundary conditions (simply supported cylinder) by using the routine functions such as trigonometric functions. The axial distribution of the axial displacement, radial displacement and electric potential of the cylinder can be presented as the important results of this paper for various non homogeneous indexes. This paper evaluates the effect of a local support on the distribution of mechanical and electrical components. This investigation indicates that a support has important influence on the distribution of mechanical and electrical components rather than a cylinder with ignoring the effect of the supports. Obtained results using present method at regions that are adequate far from two ends of the cylinder can be compared with previous results (plane elasticity and one dimensional first order shear deformation theories).

Boundary Conditions and Fire Behavior of Concrete Filled Tubular Composite Columns

  • Rodrigues, Joao Paulo C.;Correia, Antonio J.M.;Kodur, Venkatesh
    • International Journal of High-Rise Buildings
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    • v.7 no.4
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    • pp.313-325
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    • 2018
  • Concrete-filled steel tubular (CFST) members are commonly used as composite columns in modern construction. However, the current guidelines for members' fire design (EN1994-1-2) have been proved to be unsafe in case the relative slenderness is higher than 0.5. In addition, the simplified design methods of Eurocode 4 are limited to circular and square CFST columns, while in practice columns with rectangular and elliptical hollow sections are being increasingly used because of their architectural aesthetics. In the last years a large experimental research has been carried out at Coimbra University on the topic. They have been tested concrete filled circular, square, rectangular and elliptical hollow columns with restrained thermal elongation. Some parameters such as the slenderness, the type of cross-section geometry as well as the axial and rotational restraint of the surrounding structure to the column have been tested in order to evaluate their influence on the fire resistance of such columns. In this paper it is evaluated the influence of the boundary conditions (pin-ended and semi-rigid end-support conditions) on the behavior of the columns in case of fire. In these tests it could not be seen a marked effect of the tested boundary conditions but it is believed that the increasing of rotational stiffness increases the fire resistance of the columns.

Nurses' Work-family Boundary Management (간호사의 일-가정 경계선 관리)

  • Kim, Miyoung
    • Journal of Korean Academy of Nursing Administration
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    • v.19 no.1
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    • pp.17-27
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    • 2013
  • Purpose: This study was done to explore how nurses manage the boundary for work-family balance. Methods: Data were collected through in-depth interviews from February 1 to May 28, 2012. Participants were 13 married nurses with children. The constant comparative method was adapted for data analysis. Results: In this study, nurses' work-family boundary management had characteristics of integration, maintenance and control, but it was adjusted and modified over time as the order of priorities was rearranged according to changes in internal cognition and family support. Nurses strategically persuaded their families to understand their work and share housework in an effort to integrate work and family, while controlling them by managing working hours and time for themselves. Conclusion: The results of the study indicate that nurses' work has an impact on family life due to heavy workload and insufficient time, however the work-family balance can be successfully maintained with the effective separation of the two areas.

Delay Test for Boundary-Scan based Architectures (경계면 스캔 기저 구조를 위한 지연시험)

  • 강병욱;안광선
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.31A no.6
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    • pp.199-208
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    • 1994
  • This paper proposes a delay fault test technique for ICs and PCBs with the boundary-scan architectures supporting ANSI/IEEE Std 1149.1-1990. The hybrid delay fault model, which comprises both of gate delay faults and path delay faults, is selected. We developed a procedure for testing delay faults in the circuits with typical boundary scan cells supporting the standard. Analyzing it,we concluded that it is impractical because the test clock must be 2.5 times faster than the system clock with the cell architect-ures following up the state transition of the TAP controller and test instruction set. We modified the boundary-scan cell and developed test instructions and the test procedure. The modified cell and the procedure need test clock two times slower than the system clock and support the ANSI/IEEE standard perfectly. A 4-bit ALU is selected for the circuits under test. and delay tests are simulated by the SILOS simulator. The simulation results ascertain the accurate operation and effectiveeness of the modified mechanism.

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Test Methodology for Multiple Clocks in Systems (시스템 내에 존재하는 다중 클럭을 제어하는 테스트 기법에 관한 연구)

  • Lee, Il-Jang;Kim, In-Soo;Min, Hyoung-Bok
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1840-1841
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    • 2007
  • To the Boundary Scan, this architecture in Scan testing of design under the control of boundary scan is used in boundary scan design to support the internal scan chain. The internal scan chain has single scan-in port and single scan-out port that multiple scan chain cannot be used. Internal scan design has multiple scan chains, those chains must be stitched to form a scan chain as this paper. We propose an efficient Boundary Scan test structure for multiple clock testing in design.

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SOLUTION TO ${\bar{\partial}}$-PROBLEM WITH SUPPORT CONDITIONS IN WEAKLY q-CONVEX DOMAINS

  • Saber, Sayed
    • Communications of the Korean Mathematical Society
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    • v.33 no.2
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    • pp.409-421
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    • 2018
  • Let X be a complex manifold of dimension n $n{\geqslant}2$ and let ${\Omega}{\Subset}X$ be a weakly q-convex domain with smooth boundary. Assume that E is a holomorphic line bundle over X and $E^{{\otimes}m}$ is the m-times tensor product of E for positive integer m. If there exists a strongly plurisubharmonic function on a neighborhood of $b{\Omega}$, then we solve the ${\bar{\partial}}$-problem with support condition in ${\Omega}$ for forms of type (r, s), $s{\geqslant}q$ with values in $E^{{\otimes}m}$. Moreover, the solvability of the ${\bar{\partial}}_b$-problem on boundaries of weakly q-convex domains with smooth boundary in $K{\ddot{a}}hler$ manifolds are given. Furthermore, we shall establish an extension theorem for the ${\bar{\partial}}_b$-closed forms.