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61.
Bogdan Branowski Leszek Pacholski Michał Rychlik Marek Zabłocki Piotr Pohl 《人机工程学与制造业中的人性因素》2013,23(4):255-266
The article presents a new concept of combining the three dimensions (3D) of a person's manipulation space. The data concern information about the reach of the arms and biomechanical data about limiting the load of a disabled person sitting in a wheelchair. Measurement data were acquired empirically, on original measuring station. The data included, respectively, arms' reach (static and dynamic) or, alternatively, measurements of limiting forces. The obtained data were processed into virtual 3D surfaces of arms' reach and forces. These surfaces provide the required graphic model of anthropotechnical and biomechanical data. Developed model was utilized to perform a virtual analysis of the accessibility of a disabled person to technical means: in a market sale space and in the ergonomic analysis into the space of a personal car. The presented method of 3D graphic modeling of anthropometrical and biomechanical data can be universally applied in ergonomic designing of work stations not only for disabled persons. © 2011 Wiley Periodicals, Inc. 相似文献
62.
Przemysław Mazurek 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2013,17(6):1095-1106
Track-before-detect (TBD) algorithms are used for tracking systems, where the object’s signal is below the noise floor (low-SNR objects). A lot of computations and memory transfers for real-time signal processing are necessary. GPGPU in parallel processing devices for TBD algorithms is well suited. Finding optimal or suboptimal code, due to lack of documentation for low-level programming of GPGPUs is not possible. High-level code optimization is necessary and the evolutionary approach, based on the single parent and single child is considered, that is local search approach. Brute force search technique is not feasible, because there are N! code variants, where N is the number of motion vectors components. The proposed evolutionary operator—LREI (local random extraction and insertion) allows source code reordering for the reduction of computation time due to better organization of memory transfer and the texture cache content. The starting point, based on the sorting and the minimal execution time metric is proposed. The unbiased random and biased sorting techniques are compared using experimental approach. Tests shows significant improvements of the computation speed, about 8 % over the conventional code for CUDA code. The time period of optimization for the sample code is about 1 h (1,000 iterations) for the considered recursive spatio-temporal TBD algorithm. 相似文献
63.
Paweł Jankowski Dominika Ogończyk Ladislav Derzsi Wojciech Lisowski Piotr Garstecki 《Microfluidics and nanofluidics》2013,14(3-4):597-604
Modification of the surfaces of polycarbonate (PC) with the use of a solution of tin (II) chloride renders them hydrophilic. The surface draping is stable against exposure to water and to alcohols. Exposure to alkanes reduces but does not diminish the effect. The method is compatible—in using the same solvent and temperature—with the hydrophobic modification of PC (Jankowski et al. in Lab Chip 11:1151–1156, 2011). The combination of these methods makes it possible to generate single and multiple monodisperse emulsions with the use of flow-focusing junctions in systems made in PC—a material that is suitable for fabrication of multilayer, high-throughput microfluidic devices. 相似文献
64.
Paweł Jankowski Dominika Ogończyk Ladislav Derzsi Wojciech Lisowski Piotr Garstecki 《Microfluidics and nanofluidics》2013,14(5):767-774
Modification of the surfaces of polycarbonate (PC) with the use of a solution of tin (II) chloride renders them hydrophilic. The surface draping is stable against exposure to water and to alcohols. Exposure to alkanes reduces but does not diminish the effect. The method is compatible—in using the same solvent and temperature—with the hydrophobic modification of PC Jankowski et al. ( Lab Chip 11:748–752, 2011). The combination of these methods makes it possible to generate single and multiple monodisperse emulsions with the use of flow-focusing junctions in systems made in PC—material that is suitable for fabrication of multilayer, high throughput microfluidic devices. 相似文献
65.
Krzysztof Kozłowski Przemysław Herman 《Journal of Intelligent and Robotic Systems》2008,53(3):205-221
In this paper we present new control algorithms for robots with dynamics described in terms of quasi-velocities (Kozłowski,
Identification of articulated body inertias and decoupled control of robots in terms of quasi-coordinates. In: Proc. of the
1996 IEEE International Conference on Robotics and Automation, pp. 317–322. IEEE, Piscataway, 1996a; Zeitschrift für Angewandte Mathematik und Mechanik 76(S3):479–480, 1996c; Robot control algorithms in terms of quasi-coordinates. In: Proc. of the 34 Conference on Decision and Control, pp. 3020–3025,
Kobe, 11–13 December 1996, 1996d). The equations of motion are written using spatial quantities such as spatial velocities, accelerations, forces, and articulated
body inertia matrices (Kozłowski, Standard and diagonalized Lagrangian dynamics: a comparison. In: Proc. of the 1995 IEEE
Int. Conf. on Robotics and Automation, pp. 2823–2828. IEEE, Piscataway, 1995b; Rodriguez and Kreutz, Recursive Mass Matrix Factorization and Inversion, An Operator Approach to Open- and Closed-Chain
Multibody Dynamics, pp. 88–11. JPL, Dartmouth, 1998). The forward dynamics algorithms incorporate new control laws in terms of normalized quasi-velocities. Two cases are considered:
end point trajectory tracking and trajectory tracking algorithm, in general. It is shown that by properly choosing the Lyapunov
function candidate a dynamic system with appropriate feedback can be made asymptotically stable and follows the desired trajectory
in the task space. All of the control laws have a new architecture in the sense that they are derived, in the so-called quasi-velocity
and quasi-force space, and at any instant of time generalized positions and forces can be recovered from order recursions, where denotes the number of degrees of freedom of the manipulator. This paper also contains the proposition of a sliding mode control,
originally introduced by Slotine and Li (Int J Rob Res 6(3):49–59, 1987), which has been extended to the sliding mode control in the quasi-velocity and quasi-force space. Experimental results illustrate
behavior of the new control schemes and show the potential of the approach in the quasi-velocity and quasi-force space.
Authors are with Chair of Control and Systems Engineering. 相似文献
66.
Samples of -Fe (Armco) have been deformed by 50% in compression. These have then been annealed at 400 °C, considerably below the conventional recrystallization temperature, and the evolution of grain size and shape quantified. Initially the grain size is found to decrease whilst, at the same time, the grain-shape anisotropy also decreases. It is suggested that a continuous recrystallization process which favours the generation of higher angle grain boundaries is the underlying mechanism. Annealing for longer times gives rise to an increase in grain size with the development of undulations on the grain surfaces. The mechanism suggested for this behaviour involves the annihilation of segments of sub-boundaries on to a pre-existing boundary from either side of the boundary. 相似文献
67.
Using the wide-angle X-ray scattering method, the degree of crystallinity of suspension copolymers and terpolymers of acrylonitrile (AN) and divinylbenzene (DVB) were determined. Copolymers with various degrees of cross-linking (5%–50% DVB) were prepared in the presence of thermodynamically different solvents added in order to obtain porous structure. It was found that copolymers with a degree of cross-linking of 0.1% DVB have a crystallinity index below 0.2, although the crystallinity index of PAN obtained under the same conditions is 0.5. Owing to the solvation conditions, even in copolymers with a degree of cross-linking of 20% DVB, ordered regions occur, and dilution of the polymerization mixture with poor solvents cause a decrease in the degree of crystallinity of these copolymers. Terpolymers AN, butyl acrylate (BA) or vinyl acetate (VA) have less ordered structure for the same amount of DVB. Methacrylonitrile and DVB copolymers obtained under the same conditions as AN and DVB are amorphous. 相似文献
68.
J. Marciak-Kozłowska Z. Mucha M. Kozłowski 《International Journal of Thermophysics》1995,16(6):1489-1497
In this paper it has been shown that, with the advent of lasers with a very short pulse duration, the effect of thermal wave propagation becomes important. To consider this effect, hyperbolic heat conduction in thin gold films was studied. It was shown that for heat fluxes of the order 108 W·cm–2, a thermal wave is generated in thin gold films. The consideration of the hyperbolicity of heat transfer enables one to describe the temperature profile with one value of fluence. 相似文献
69.
70.
Bioimaging: Shaping Luminescent Properties of Yb3+ and Ho3+ Co‐Doped Upconverting Core–Shell β‐NaYF4 Nanoparticles by Dopant Distribution and Spacing (Small 47/2017) 下载免费PDF全文