• 제목/요약/키워드: Cellular behavior

검색결과 286건 처리시간 0.022초

복잡한 행동을 위한 셀룰라 오토마타 기반 신경망 모듈의 동적선택 (Dynamic Selection of Neural Network Modules based on Cellular Automata for Complex Behaviors)

  • 김경중;조성배
    • 대한전기학회논문지:시스템및제어부문D
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    • 제51권4호
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    • pp.160-166
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    • 2002
  • Since conventional mobile robot control with one module has limitation to solve complex problems, there have been a variety of works on combining multiple modules for solving them. Recently, many researchers attempt to develop mobile robot controllers using artificial life techniques. In this paper, we develop a mobile robot controller using cellular automata based neural networks, where complex tasks are divided to simple sub-tasks and optimal neural structure of each sub-task is explored by genetic algorithm. Neural network modules are combined dynamically using the action selection mechanism, where basic behavior modules compete each other by inhibition and cooperation. Khepera mobile robot simulator is used to verify the proposed model. Experimental results show that complex behaviors emerge from the combination of low-level behavior modules.

알루미늄봉을 이용한 셀(Cell) 채움재의 전단거동에 관한 연구 (A Study on Shear Behavior of Fill in Cellular Bulkhead by Two Dimensional Model Test with Aluminium Rods)

  • 장정욱
    • 한국지반공학회지:지반
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    • 제12권5호
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    • pp.55-62
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    • 1996
  • Lateral loading model tests were performed on the rigid box-shaped cellular bulkhead by displacement-controlled method. The materials of ground and fill used in this study are two aluminium rods with different sections. The behalf·iotas of ground and fill were recorded by photo/video techniques and failure mechanism created in ground and fill has been simulated two-야mensionally. Also the theoretical consideration about the test results was done on the basis of Hansen's earth pressure theory. As a result, the shape of sliding face the location of sliding face and the loading height was also investigated.

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Cellular and corrugated cross-sectioned thin-walled steel bridge-piers/columns

  • Ucak, Alper;Tsopelas, Panos
    • Structural Engineering and Mechanics
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    • 제24권3호
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    • pp.355-374
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    • 2006
  • Thin walled steel bridge-piers/columns are vulnerable to damage, when subjected to earthquake excitations. Local buckling, global buckling or interaction between local and global buckling usually is the cause of this damage, which results in significant strength reduction of the member. In this study new innovative design concepts, "thin-walled corrugated steel columns" and "thin-walled cellular steel columns" are presented, which allow the column to undergo large plastic deformations without significant strength reduction; hence dissipate energy under cyclic loading. It is shown that, compared with the conventional designs, circular and stiffened box sections, these new innovative concepts might results in cost-effective designs, with improved buckling and ductility properties. Using a finite element model, that takes the non-linear material properties into consideration, it is shown that the corrugations will act like longitudinal stiffeners that are supporting each other, thus improving the buckling behavior and allowing for reduction of the overall wall thickness of the column.

지역사회 대상의 휴대폰 문자메시지를 이용한 건강교육 중재의 효과 (Effects of Health Education using Short Messaging Service of Cellular Phone)

  • 김현
    • 성인간호학회지
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    • 제25권3호
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    • pp.241-249
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    • 2013
  • Purpose: The aim of the study was to identify the effects of education from using cellular phones and a short messaging service. Methods: Collected data included baseline demographics, blood pressure, abdominal circumference, total cholesterol, body mass index and health behavior index (Dietary Practice Guidelines Score, Physical Activity, Drinking frequency, Stress score, Subjective health status, and Action change stage score). Data were collected at public health centers in Chungcheongnam-do from January to December, 2011. Data obtained from Individual health counseling Programs in Chungcheongnam-do. Analysis was divided into health risk group and Disease management group, using a paired t test. Results: Following the education of using short messaging service of cellular phones Health risk group was a reduction in the systolic blood pressure, diastolic blood pressure, waist circumference. Disease management group was a reduction in the systolic blood pressure and body mass index. In both groups, there were improvement in the Health behavior index; dietary practice guidelines score, physical activity, stress score, subjective health status and action change stage scores. Conclusion: These results indicated that education using short messaging service of cellular phone for Community was effective in improving health behaviors and status. By applying the results, development of customized teaching messages for stable settlement is required.

Recent advances in intravital microscopy for investigation of dynamic cellular behavior in vivo

  • Choo, Yeon Woong;Jeong, Juhee;Jung, Keehoon
    • BMB Reports
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    • 제53권7호
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    • pp.357-366
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    • 2020
  • Currently, most biological research relies on conventional experimental techniques that allow only static analyses at certain time points in vitro or ex vivo. However, if one could visualize cellular dynamics in living organisms, that would provide a unique opportunity to study key biological phenomena in vivo. Intravital microscopy (IVM) encompasses diverse optical systems for direct viewing of objects, including biological structures and individual cells in live animals. With the current development of devices and techniques, IVM addresses important questions in various fields of biological and biomedical sciences. In this mini-review, we provide a general introduction to IVM and examples of recent applications in the field of immunology, oncology, and vascular biology. We also introduce an advanced type of IVM, dubbed real-time IVM, equipped with video-rate resonant scanning. Since the realt-ime IVM can render cellular dynamics with high temporal resolution in vivo, it allows visualization and analysis of rapid biological processes.

Cellular Automata Transform based Invisible Digital Watermarking in Middle Domain for Gray Images

  • Li, Xiao-Wei;Kim, Seok-Tae
    • Journal of information and communication convergence engineering
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    • 제9권6호
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    • pp.689-694
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    • 2011
  • Cellular automata are discrete dynamical systems, which provide the basis for the synthesis of complex emergent behavior. This paper proposes a new algorithm of digital watermarking based on cellular automata transform (CAT). The idea of two-dimensional CAT is introduced into the algorithm. After the original image is disassembled with 2D CAT, the watermark information is embedded into the Middle-frequency of the carrier picture. Cellular automata have a huge number of combinations, such as gateway values, rule numbers, initial configuration, boundary condition, etc. Using CAT, the robustness of the watermark will be tremendous strengthened as well as its imperceptibility. Experimental results show that this algorithm can resist some usual attacks such as compression, sharpening and so on. The proposed method is robust to different attacks and is more security.

Stability and vibration behavior of cellular plates with different cell arrays using a numerical approach

  • Chuan-Xiong Li
    • Structural Engineering and Mechanics
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    • 제85권6호
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    • pp.709-716
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    • 2023
  • In this paper, the shape factors of cellular meta-material plates (MMPs) having diverse cell arrays have been determined as the first attempt to finally examine their stability and vibrational frequencies. The MMPs are actually constructed from cylindrical or cubic cellular cores and two face sheets. Sandwich-like MMPs with circular and square holes in the face sheets have been selected in such a way that the effective material properties depend on the cellular architectures. For verifying the frequency results, finite element (FE) simulations are done in Abaqus software. Several graphical results have been represented to explore the effects of cellular architectures on vibrational frequencies and dynamic responses of the MMPs. Also, the deflection-frequency and stability curves in the case of forced vibrations have been plotted for diverse cell arrays.

The uniaxial strain test - a simple method for the characterization of porous materials

  • Fiedler, T.;Ochsner, A.;Gracio, J.
    • Structural Engineering and Mechanics
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    • 제22권1호
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    • pp.17-32
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    • 2006
  • The application of cellular materials in load-carrying and security-relevant structures requires the exact prediction of their mechanical behavior, which necessitates the development of robust simulation models and techniques based on appropriate experimental procedures. The determination of the yield surface requires experiments under multi-axial stress states because the yield behavior is sensitive to the hydrostatic stress and simple uniaxial tests aim only to determine one single point of the yield surface. Therefore, an experimental technique based on a uniaxial strain test for the description of the influence of the hydrostatic stress on the yield condition in the elastic-plastic transition zone at small strains is proposed and numerically investigated. Furthermore, this experimental technique enables the determination of a second elastic constant, e.g., Poisson's ratio.

ANXA2 Regulates the Behavior of SGC-7901 Cells

  • Sun, Meng-Yao;Xing, Rui-Huan;Gao, Xiao-Jie;Yu, Xiang;He, Hui-Min;Gao, Ning;Shi, Hong-Yan;Hu, Yan-Yan;Wang, Qi-Xuan;Xu, Jin-Hui;Hou, Ying-Chun
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권10호
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    • pp.6007-6012
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    • 2013
  • ANXA2, a member of the annexin family, is overexpressed and plays important roles in tumor development. However, the significance of ANXA2 expression in gastric carcinoma has not been clarified.To elucidate its roles in growth of gastric cancer, ANXA2 expression in SGC-7901 cells was inhibited with a designated siRNA, then cell proliferation, cell cycling, apoptosis and motility were determined by MTT assay, flow cytometry, Hoechst 33342 staining and wound healing assay, respectively. To further assess the behavior of ANXA2 deleted SGC-7901 cells, changes of microstructures were observed under fluorescence microscopy, laser scanning confocal microscopy and electron microscopy. We found that inhibition of ANXA2 expression caused cell proliferation to decrease significantly with G1 arrest, motility to be reduced with changes in pseudopodia/filopodia structure and F-actin and ${\beta}$-tubulin expression, and apoptosis to be enhanced albeit without significance. At the same time, ANXA2 deletion resulted in fewer pseudopodia/filopodia, non-stained areas were increased, contact inhibition among cells reappeared, and expression of F-actin and ${\beta}$-tubulin was decreased, with induction of polymerized disassembled forms. Taken together, these data suggest that ANXA2 overexpression is important to maintain the malignancy of cancer cells, and this member of the annexin family has potential to be considered as a target for the gene therapy of gastric carcinoma.