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1.
Taking into consideration a study published 10 years ago on sexual disturbances of students at the University of S?o Paulo, the importance of the subject is discussed, along with the creation in 1993 of the Sexuality Project at the university hospital of the University of S?o Paulo School of Medicine. In its first year, this multidisciplinary project attended 140 patients with sexual dysfunctions (associated or not to other clinical manifestations); the majority were younger than 60 years-old, and 80 percent were male. 相似文献
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The existing measurements of global solar radiation and sunshine duration for Yemen are examined. The errors of estimating solar radiation from sunshine hour measurements using Angstrom's relation are evaluated. As a simple predictor for global radiation, an average Ansgtrom relations in the form
for all stations is evaluated. Other Angstrom correlation relations are also proposed by classifying the stations under into four groups. The estimated results are compared and seem to be satisfactory in the latter case. 相似文献
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Abdulrahman Al-Ahmari Mohammad Ashfaq Abdullah Alfaify Basem Abdo Abdulrahman Alomar Abdelnaser Dawud 《Journal of Mechanical Science and Technology》2016,30(1):345-352
Electron beam melting (EBM) has been found to be a promising technology for producing complex shaped parts from gamma titanium aluminide alloys (γ-TiAl). The parts produced by this process are projected to have dimensions very close to the desired final shapes. However, the surface roughness of the parts produced by EBM is excessively rough. In many applications, it is necessary to improve the quality of manufactured parts using a convenient post process. This paper determines process parameters of end milling when it is used as a post process for the parts produced by EBM. Design of experiments has been used to study the effect of the selected input parameters of end milling (spindle speed, feed rate, depth of cut and coolant type) on the surface roughness of γ-TiAl parts. Response surface methodology is used to develop a predictive model for surface roughness. Effects of the selected milling process are investigated. This paper also optimizes the selected process parameters to minimize the value of the obtained surface roughness. 相似文献
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Hassoun S. Kudlugi M. Pryor D. Selvidge C. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2005,13(2):278-287
The availability of millions of transistors on a single chip has allowed the creation of complex on-chip systems. The functional verification of such systems has become a challenge. Simulation run times are increasing, and emulation is now a necessity. Creating separate verification environments for simulation and emulation slows the design cycle and it requires additional human efforts. This paper describes a layered architecture suitable for both simulation and emulation. The architecture uses transactions for communication and synchronization between the driving environment (DE) and the device under test (DUT). Transactions provide synchronization only as needed and cycle and event-based synchronization common in emulators. The result is more efficient development of the DE and 100% portability when moving from simulation to emulation. We give an overview of our layered architecture and describe its implementation. Our results show that, by using emulation, the register-transfer level (RTL) implementation of an industrial design can be verified in the same amount of time it takes to run a C-based simulation. We also show two orders of magnitude speeds up over simulations of C and RTL through a programming language interface 相似文献
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Secretory middle ear otitis is of difficult assessment in children with severe hearing impairment. This otitis, very frequent in infants and children, influences negatively the auditive capacity and apprenticeship as well. Our study deals with the prevalence and severity of the secretive middle ear otitis in an scholar population handicapped by a heavy hypoacusia. Demographically, etiologic and seasonal correlations are considered in the paper. The outcome shows a high incidence of the condition, an inversely relation with the age, an evident seasonal distribution and the absence of correlation between etiology of middle ear disease and sensorineural deafness. 相似文献
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Abdo AbdelMonem Shaalan M. I. Ramadan 《Journal of Infrared, Millimeter and Terahertz Waves》2010,31(8):958-968
This paper presents two design compact hexagonal monopole antennas for ultra-wideband applications. The two antennas are fed
by a single microstrip line . The Zeland IE3D version 12 is employed for analysis at the frequency band of 4 to 14 GHz which
has approved as a commercial UWB band. The experimental and simulation results exhibit good agreement together for antenna
1. The proposed antenna1 is able to achieve an impedance bandwidth about 111%. The proposed antenna2 is able to achieve an
impedance bandwidth about (31.58%) for lower frequency and (62.54%) for upper frequency bandwidth. A simulated frequency notched
band ranging from 6.05 GHz to 7.33 GHz and a measured frequency notched band ranging from 6.22 GHz to 8.99 GHz are achieved
and gives one narrow band of axial ratio (1.43%). The proposed antennas can be used in wireless ultra-wideband (UWB) communications. 相似文献
10.
Stabilization loop of a two axes gimbal system using self-tuning PID type fuzzy controller 总被引:3,自引:0,他引:3
The application of inertial stabilization system is to stabilize the sensor's line of sight toward a target by isolating the sensor from the disturbances induced by the operating environment. The aim of this paper is to present two axes gimbal system. The gimbals torque relationships are derived using Lagrange equation considering the base angular motion and dynamic mass unbalance. The stabilization loops are constructed with cross coupling unit utilizing proposed fuzzy PID type controller. The overall control system is simulated and validated using MATLAB. Then, the performance of proposed controller is evaluated comparing with conventional PI controller in terms of transient response analysis and quantitative study of error analysis. The simulation results obtained in different conditions prove the efficiency of the proposed fuzzy controller which offers a better response than the classical one, and improves further the transient and steady-state performance. 相似文献