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21.
Sidney Harold Newman died at his home in Bethesda, Maryland, on January 1, 1989. His professional career spanned more than 50 years and included several career transitions, all dedicated to serving and advancing the field of psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
22.
Robotic-assisted surgery is a continuously developing field, as robots have demonstrated clear benefits in the operating room. This paper presents the inverse dynamic model (in the case of using the laparoscope as a surgical instrument) and some characteristics of a 5-DOF hybrid parallel robot designed for minimally invasive surgery. The new inverse dynamic model is obtained using the virtual work method on the basis of dynamically equivalent lumped masses. The simulation and numerical results have been obtained for the experimental model of the developed PARASURG-5M robot, showing that the analytical inverse dynamic model could be used in the control of the robot. Finally, a comparison between the simulation data obtained in Matlab (IDM) with the simulation data through a Multi-body Simulation software (MBS), namely Adams (MBS) has been performed.  相似文献   
23.
Reconfigurable robots can be defined as a group of robots that can have different geometries, thus obtaining different structures derived from the basic one, having different degrees of freedom and workspaces. Thanks to the optimum dexterity they offer, the user can accomplish a large variety of industrial tasks, using a structurally optimized robot leading towards better energy control and efficiency especially in case of batch size production lines where the task (for the robot) may vary periodically. Reconfigurable systems are a challenge for numerous scientists, due to the advantage of dealing with changes and uncertainties on the ever-changing manufacturing market. One of the main problems of reconfigurable robots is the proper structural geometry determination, so that the resulting structure is able to perform a variety of tasks. This paper presents the structural design of an innovative parallel robot with six degrees of freedom and its proposed configurations with five, four, three and two degrees of freedom. The kinematic analysis and the workspace representations of all the presented configurations of the parallel robot, called Recrob, are also presented.  相似文献   
24.
A detailed account of the experimental methodology of surface pump-probe femtosecond-laser mass spectrometry is presented. This recently introduced technique enables the direct time-resolved investigation of surface reaction dynamics by monitoring the mass and the relative velocity of intermediates and products of a photoinduced surface reaction via multiphoton ionization. As a model system, the photodissociation dynamics of methyl iodide adsorbed at submonolayer coverage on magnesia ultrathin films is investigated. The magnesia surface preparation and characterization as well as the pulsed deposition of methyl iodide are described. The femtosecond-laser excitation (pump) and, in particular, the resonant multiphoton ionization surface detection (probe) schemas are discussed in detail. Results of pump-probe time-resolved methyl and iodine atom detection experiments are presented and the potential of this method for velocity-resolved photofragment analysis is evaluated.  相似文献   
25.
Syto9 and probe‐based multiplex real‐time PCR assays for simultaneous detection of a group of foodborne pathogens (named SYLC group), targeting Salmonella spp. (invA gene), Yersinia enterocolitica (ystA gene), Listeria monocytogenes (hly gene) and Campylobacter spp. (rrna gene), have been developed. The Syto9 assay generates amplicon DNA melting curve with four peaks of 86.5 ± 0.5, 84 ± 0.5, 81.5 ± 0.5 and 90.5 ± 0.5 °C corresponding Salmonella spp., Y. enterocolitica, L. monocytogenes and Campylobacter spp. targets, respectively. The sensitivities of the Syto9 and TaqMan assays in artificially inoculated chicken wing rinses were in a range of 3.2 × 102 to 3.1 × 104 and 9.8 × 102 to 1.9 × 104 colony‐forming units per millilitre, respectively, depending on the pathogen. All tested target strains (n = 100) were correctly detected by the both assays, whereas nontarget strains (n = 100) demonstrated no cross‐reactivity representing 100% specificity. The assays are suitable for application in qualitative and quantitative detection of SYLC group pathogens in food matrices.  相似文献   
26.
We report a 36-year-old man with proximal dominant muscle weakness, thymic tumor, diabetes mellitus, hypokalemia, and increased levels of plasma ACTH and cortisol. The diagnosis of carcinoid tumor was made on the basis of pathological findings in the biopsied specimen of the thymic tumor. The proximal muscle weakness was considered to be due to steroid myopathy resulting from the overproduction of cortisol from the adrenal glands induced by the ectopic ACTH secreted by the thymic carcinoid tumor. Although thymoma in frequently associated with myasthenia gravis, we should also consider carcinoid tumors in patients with a thymic tumor presenting with a proximal muscle weakness.  相似文献   
27.
To evaluate the importance of the water holding capacity for the elastically stored energy of protein gels, a range of gels were created from proteins from different origin (plant: pea and soy proteins, and animal: whey, blood plasma, egg white proteins, and ovalbumin) varying in network morphology set by the protein concentration, pH, ionic strength, or the presence of specific ions. The results showed that the observed positive and linear relation between water holding (WH) and elastically stored energy (RE) is generic for globular protein gels studied. The slopes of this relation are comparable for all globular protein gels (except for soy protein gels) whereas the intercept is close to 0 for most of the systems except for ovalbumin and egg white gels. The slope and intercept obtained allows one to predict the impact of tuning WH, by gel morphology or network stiffness, on the mechanical deformation of the protein‐based gel. Addition of charged polysaccharides to a protein system leads to a deviation from the linear relation between WH and RE and this deviation coincides with a change in phase behavior.  相似文献   
28.
The geometric and kinematic models of a new surgical hybrid robot used for camera and active instruments positioning are presented in this paper. The robot workspace is computed and illustrated following the singularities analysis. The robot structure consists of two modules: the PARAMIS robot, and the new serial positioning module. The serial positioning module is used to obtain a mechanically fixed remote center of motion (RCM), enabling the structure to manipulate also active instruments. The new robot provides the necessary motion control to respect the particularities and restrictions of surgical applications. The detailed workspace analysis demonstrates the importance of the relative positioning between the robot and the patient. A constructive solution of the new serial module, the numerical results and conclusions from the performed simulations are described.  相似文献   
29.
The indirect measurement method of the contour width deformation of the embroidery element is presented in the work. The square-shaped, directly measured, embroidery element is compared to its digital image. Together with the used test methods steps, the reliability criteria for this method are presented as well. The reliability of the method of measuring the geometrical parameters of a closed contour element of an embroidered square shape is evaluated by analyzing its systematic and random errors and by calculating the total standard uncertainty. In assessing the accuracy of the measurement method, there is also a talk about a comprehensive assessment of measurement uncertainty. Measurement uncertainties are considered to be one of the most important parameters of the ability of a method to determine the possibilities of using and applying the method. When measuring the parameters of real samples, the components of total uncertainty related to the characteristics of the specimen (weave, surface density, filling characteristics, direction of the fabric yarn), their variation within certain limits and possible correlation among these components, influence of the standard means, data processing, digital image calibration were evaluated. It has been determined during the research that a negative error ~2.4% with expanded uncertainty ~3.3% complying with the requirements of the reliability of the method is typical for the deformation measurement method applied for the measurement of the five (6, 10, 14, 18, and 22?mm) elements of different contour widths. Because of that the evaluation of the uncertainty according its components is useful while analyzing the factors which have an impact on the deformation.  相似文献   
30.
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