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31.
This paper deals with the modeling of a robot with a new kinematicdesign. All joint movements in this robot are transmitted via concentrictubes and bevel gears. D'Alembert's principle is used to derivethe equations of motion for rigid and elastic models, consideringthe elastic deflections of the arms and inner tubes. Implementing therecursive algorithm, both symbolical and numerical methods were tested.The advantages and problems are discussed. In order to verify the model,simulation results are compared with measurements. 相似文献
32.
The focus of this article is to review recent techniques in proteomic analysis of ocular fluids. These fluids include tears, aqueous humor, and vitreous, they will also be compared to serum analysis. Furthermore, we attempt to summarize some disease correlated biomarkers in ocular fluids that were discovered through different proteomic techniques in eye diseases like dry eye, glaucoma, age-related macular degeneration, uveitis, or diabetic retinopathy. This review is trying to point out the importance of these biomarkers for clinical applications. 相似文献
33.
34.
W Beischer L Keller M Maas E Scherfer EF Pfeiffer 《Canadian Metallurgical Quarterly》1976,54(15):709-715
Synthetic human C-peptide bearing a Tyrosine group at its amino end is labelled with 125iodine using chloramin T or hydrogen peroxide and lactoperoxidase. The results are compared applying both methods. Antiserum to synthetic human C-peptide (without Tyrosine) which was partially compared to rabbit albumin, is raised in guinea pigs and goats. Goats show to be superior to guinea pigs concerning antibody production. The so-called "hook effect" phenomenon is observed in setting up the standard curves for the radioimmunoassay. Monotonically decreasing standard curves are obtained on dilution of antiserum with a high antibody titer which was produced by repeated immunization in goats. Free C-peptide and C-peptide bound to antiserum are separated with the anxion exchange resin Amberlite. Using this separation technique we excluded unspecific binding of labelled C-peptide to protein fractions in serum of diabetics. The sensitivity of our radioimmunoassay is approx. 0.3 ng C-peptide/ml serum. Intra- and interassay variability are below 10%. Human proinsulin is the only substance found to crossreact with the antiserum. 相似文献
35.
This paper describes a number of significant modeling considerations for SiGe heterojunction bipolar transistor power amplifiers operating at millimeter-wave frequencies. Small- and large-signal model-to-hardware correlation is presented for single transistor amplifiers, as well as for a combined dual-stage amplifier up to 65 GHz. The relevant parasitic effects are described along with the proposed modeling approach for each of them. The limits of the standard Vertical Bipolar Inter-Company device model at high-injection and their effect on the prediction of the achievable large-signal compression and power-added efficiency are also discussed. 相似文献
36.
Zwick T. Chandrasekhar A. Baks C.W. Pfeiffer U.R. Brebels S. Gaucher B.P. 《Microwave Theory and Techniques》2006,54(3):1001-1010
The focus of this paper is the determination of the complex permittivity of chip packaging materials at millimeter-wave frequencies. After a broad overview of existing measurement techniques, three methods will be presented that have been established for the dielectric property determination of substrate, as well as mold materials (encapsulants, under-fill, etc.) in the millimeter-wave frequency range. First, the open resonator used here will be briefly described. It allows accurate determination of the dielectric constant and loss of thin sheet substrate materials from below 20 GHz to above 100 GHz. Second, a filled waveguide method is explained in detail. The setup used here can determine the complex dielectric properties of mold materials from 70 to 100 GHz. Third, the method based on covered transmission lines will be described in detail. The used lines allow measurements from below 40 GHz to approximately 90 GHz. Verification of all three methods will be provided by inter-comparison and comparison to values from the literature. Additionally, results for several typical substrate and mold materials that are available for millimeter-wave packaging will be shown and discussed. 相似文献
37.
Patricia R. Pfeiffer Angela R. Bielefeldt Tissa Illangasekare Bruce Henry 《Canadian Metallurgical Quarterly》2005,131(10):1447-1452
Laboratory experiments were conducted to investigate the abiotic interactions of soybean oil (SoyOil) and chlorinated ethene (CE) nonaqueous phase liquids (NAPLs). The mixed NAPL density and interfacial tension behaved ideally, as predicted by the volume ratio. The mixed NAPL viscosity increased exponentially from that of the pure CE to that of pure SoyOil as the volume fraction increased. The measured contact angle was highly variable and was unpredictable as a function of the volume composition of the mixed NAPL. The physical property effects indicate that the mobilization of residual CE NAPLs because of SoyOil injection is unlikely. Equilibrium dissolution of CEs from the NAPL mixtures behaved linearly as a function of the mole fraction. Dissolved SoyOil in simulated groundwater enhanced the dissolution of trichloroethene (TCE) during flow tests, increasing the effluent TCE concentration from 141?to?202?mg/L. The ready intermingling of the CE dense nonaqueous phase liquids (DNAPLs) and SoyOil indicate that such interactions may be significant at sites where vegetable oil is injected into DNAPL source areas to enhance in situ anaerobic bioremediation. 相似文献
38.
McCaslin Shannon E.; Jacobs Gerard A.; Meyer David L.; Johnson-Jimenez Erika; Metzler Thomas J.; Marmar Charles R. 《Canadian Metallurgical Quarterly》2005,36(3):246
The American Red Cross is the largest nongovernmental organization responding to disasters in the United States. This study investigated the impact of negative life change occurring in the year following the September 11, 2001, terrorist attacks on levels of distress among 757 Red Cross Disaster Services Human Resources (national disaster team) employees and volunteers who responded to this disaster. Negative life change in the year following disaster response fully mediated the relationship between disaster response and symptoms of depression and partially mediated the responses between disaster response and posttraumatic stress and anxiety symptoms. Results highlight the importance of life experiences in the year following disaster response and, therefore, the education and follow-up services provided to disaster workers prior to and following disaster assignment. Suggestions for monitoring disaster-related stress during and following assignment are provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
39.
We present a new solver for coupled nonlinear elliptic partial differential equations (PDEs). The solver is based on pseudo-spectral collocation with domain decomposition and can handle one- to three-dimensional problems. It has three distinct features. First, the combined problem of solving the PDE, satisfying the boundary conditions, and matching between different subdomains is cast into one set of equations readily accessible to standard linear and nonlinear solvers. Second, touching as well as overlapping subdomains are supported; both rectangular blocks with Chebyshev basis functions as well as spherical shells with an expansion in spherical harmonics are implemented. Third, the code is very flexible: The domain decomposition as well as the distribution of collocation points in each domain can be chosen at run time, and the solver is easily adaptable to new PDEs. The code has been used to solve the equations of the initial value problem of general relativity and should be useful in many other problems. We compare the new method to finite difference codes and find it superior in both runtime and accuracy, at least for the smooth problems considered here. 相似文献
40.
Relations of overt and relational aggression with perceived popularity among children and early adolescents were examined in 2 studies (Ns = 607 and 1,049). Among older youths, positive concurrent relations found between overt aggression and perceived popularity became nonsignificant when relational aggression was controlled, whereas positive associations found between relational aggression and perceived popularity held when overt aggression was controlled. Aggression and perceived popularity were not positively related for the younger participants. The 2nd study also examined the temporal ordering of these relations over 6 months. For older girls, positive relations between relational aggression and perceived popularity were bidirectional. For older boys, relational aggression did not predict increased perceived popularity, but perceived popularity predicted increased relational aggression. Implications for intervention are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献