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1.
In this paper, the implementation of a line-of-sight (LOS) task-space sensing methodology is presented for guidance-based microlocalization of robotic end-effectors. The novelty of the overall system is its applicability to cases that do not allow for the direct proximity measurement of the end-effector's pose (position and orientation). The mobility of the localization application dictates the minimum number and the type (planar or spatial) of the LOS that would be necessary to use and, consequently, the exact configuration of the sensing system. Although the main focus of the paper is the presentation of the proposed LOS sensing system, a brief discussion of a robot-guidance method, which relies on the use of this sensing system, is also included. Extensive experiments conducted for a high-precision 3-DOF (degrees of freedom) planar robotic platform utilizing the overall guidance system validated our research.  相似文献   
2.
1 INTRODUCTIONSkeletalreconstructionorregenerationisre quiredincasesinvolvinglargedefectscreatedbytu morresection ,trauma ,andskeletalabnormalities .Graftsandflapsofautogenoustissuearetwoofthemostsuccessfulmeansofreconstructionbecausetheyallowthetransplantationofbonecontainingbioactivemolecules,livecells ,andfrequently ,avascularsup plythatallowthetransplanttosurviveandremodeleveninhostileradiatedenvironments .However ,onlyaminimalamountoftissuecanbeharvestedforauto grafts,anditisverydiff…  相似文献   
3.
The study presented is an example of the assessment of the relative sustainability of either option for disposal of domestic sanitary waste, either via the toilet or via the solid waste route. This required an evaluation of the total (social, economic, environmental, and technical) benefit/cost of implementing and adopting the alternative routes and an assessment of public responsiveness to encouragement to change sanitary waste disposal practices. It illustrates how, even for an apparently straightforward either/or question, the assessment of relative sustainability is complex and the amount of data needed to quantify sustainability indicators is prodigious. The study also provides an appraisal of the effectiveness of public campaigns to reduce waterborne disposal. Important information regarding public attitude and behavior in relation to wastewater systems has been acquired and lessons for ways of encouraging behavioral change to more sustainable ways of living have been gleaned.  相似文献   
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Use of cysteamine hydrochloride (Cys-HCl) protected gold nanorods (GNRs) as efficient carrier of widely used anti-cancer drug doxorubicin using folic acid as navigational molecule is presented in this work. GNRs were found to have excellent drug loading capacity of >97 %. A detailed comprehension of in vitro drug release profile under ideal physiological condition was found to obey 1st order kinetics at pH 6.8, 5.3 and 7.2, an ideal milieu for drug delivery to solid tumours.  相似文献   
7.
Recent developments focusing on novel hydrogen storage media have helped to benchmark nanostructured carbon materials as one of the ongoing strategic research areas in science and technology. In particular, certain microporous carbon powders, carbon nanomaterials, and specifically carbon nanotubes stand to deliver unparalleled performance as the next generation of base materials for storing hydrogen. Accordingly, the main goal of this report is to overview the challenges, distinguishing traits, and apparent contradictions of carbon-based hydrogen storage technologies and to emphasize recently developed nanostructured carbon materials that show potential to store hydrogen by physisorption and/or chemisorption mechanisms. Specifically touched upon are newer material preparation methods as well as experimental and theoretical attempts to elucidate, improve or predict hydrogen storage capacities, sorption–desorption kinetics, microscopic uptake mechanisms and temperature–pressure–loading interrelations in nanostructured carbons, particularly microporous powders and carbon nanotubes.  相似文献   
8.
The atomic force microscope (AFM) system has evolved into a useful tool for direct measurements of intermolecular forces with atomic-resolution characterization that can be employed in a broad spectrum of applications. The distance between cantilever tip and sample surface in non-contact AFM is a time-varying parameter even for a fixed sample height, and typically difficult to identify. A remedy to this problem is to directly identify the sample height in order to generate high-precision atomic-resolution images. For this, the microcantilever (which forms the basis for the operation of AFM) is modeled as a single mode approximation and the interaction between the sample and cantilever is derived from a van der Waals potential. Since in most practical applications only the microcantilever deflection is accessible, we will use merely this measurement to identify the sample height. In most non-contact AFMs, cantilevers with high-quality factors are employed essentially for acquiring high-resolution images. However, due to high-quality factor, the settling time is relatively large and the required time to achieve a periodic motion is long. As a result, identification methods based on amplitude and phase measurements cannot be efficiently utilized. The proposed method overcomes this shortfall by using a small fraction of the transient motion for parameter identification, so the scanning speed can be increased significantly. Furthermore, for acquiring atomic-scale images of atomically flat samples, the need for feedback loop to achieve setpoint amplitude is basically eliminated. On the other hand, for acquiring atomic-scale images of highly uneven samples, a simple PI controller is designed to track the desired constant sample height. Simulation results are provided to demonstrate the feasibility of the approach for both sample height identification and tracking the desired sample height.  相似文献   
9.
In this paper, the discrete velocity model proposed by Kataoka and Tsutahara (Phys. Rev. E 69(5):056702, 2004) for simulating inviscid flows is employed. Three approaches for improving the stability and the accuracy of this model, especially for high Mach numbers, are suggested and implemented in this research. First, the TVD scheme (Harten in J. Comput. Phys. 49:357?C393, 1983) is used for space discretization of the convective term in the Lattice Boltzmann equation. Next, the modified Lax-Wendroff with artificial viscosity is employed to increase the robustness of the method in supersonic flows. Finally, a combination of TVD and the 2nd order derivative of the distribution function is employed using a differentiable switch. It is found that the recent technique is a more suitable approach for a wide range of Mach numbers. Moreover, the WENO scheme for space discretization has been applied and compared with these newly applied methods.  相似文献   
10.
Hardware Trojan horses (HTHs) are among the most challenging treats to the security of integrated circuits. Path-delay fingerprinting has shown to be a promising HTH detection approach. However, previous work in this area incurs a large hardware cost or requires expensive testing techniques. Moreover, the relation between technology mapping and the efficiency of delay-based HTH detection have not yet been studied. In this paper, we present a HTH detection method which uses an effective test-vector selection scheme and a path-delay measurement structure. Furthermore, we demonstrate the large impact of technology mapping on the effectiveness of delay-based HTH detection. We also show that delay-based detection methods are highly scalable. In case of choosing an area-driven design strategy, the average HTH detection probability of our approach is about 63%, 78% and 90% if false alarm rate is 0%, 2% and 16%, respectively. However, with modifications in the technology mapping, the results show improvements to 85%, 94% and 99%, at the cost of about 20% area overhead. In addition, the efficiency of our method would not decrease for large benchmarks with thousands of gates.  相似文献   
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