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91.
Reviews the book, Self and identity in modern psychology and Indian thought by Anand C. Paranjpe (see record 1998-08117-000). This book is an exemplary philosophical-psychological achievement, the result of extensive, sophisticated, and enlightened research. Paranjpe analyzes and compares, based on knowledge of the epistemological, ontological, and ethical foundations of psychology in both the West and India, the problem of person, self, and identity. This is a significant book, not only for the field of the history and theory of psychology but also for psychology in general. Paranjpe, who provides a wealth of knowledge unknown to most Western psychologists, demonstrates that the presumption that Western and Indian psychologies are basically incommensurable is wrong. Psychologists who are genuinely concerned with a science that goes beyond the connection of variables, who believe that incorporating a multicultural perspective into psychology will strengthen the discipline, and who talk about globalization but are interested in the generic meaning of this concept, cannot ignore this masterpiece. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
92.
We consider an envelope-constrained (EC) optimal filter design problem involving a quadratic cost function and a number of linear inequality constraints. Using the duality theory and the space transformation function, the optimal solution of the dual problem can be computed by finding the limiting point of an ordinary differential equation given in terms of the gradient flow. An iterative algorithm is developed via discretizing the differential equation. From the primal-dual relationship, the corresponding sequence of approximate solutions in the original EC filtering problem is obtained. Based on these results, an adaptive algorithm is constructed for solving the stochastic EC filtering problem in which the input signal is corrupted by an additive random noise. For illustration,a practical example is solved for both noise-free and noisy cases  相似文献   
93.
FIR filter design over discrete coefficients and least square error   总被引:2,自引:0,他引:2  
The difference routing digital filter (DRDF) consists of an FIR filter followed by a first-order integrator. This structure with power-of-two coefficients has been studied as a means of achieving low complexity, high sampling rate filters which can be implemented efficiently in hardware. The optimisation of the coefficients has previously been based on a time-domain least-squares error criterion. A new design method is proposed that includes a frequency-domain least-squares criterion with arbitrary frequency weighting and an improved method for handling quantisation of the filter coefficients. Simulation studies show that the new approach yields an improvement of up to 7 dB over existing methods and that oversampling can be used to improve performance  相似文献   
94.
Structural adhesive joints were subjected to high loading rates in mode I and their resulting fracture behaviour was studied in detail. Joints were formed between unidirectional carbon-fibre epoxy composites and between aluminium alloy substrates bonded with a tough, single-part automotive adhesive (XD4600) from Dow Automotive. Double cantilever beam (DCB) and tapered double cantilever beam (TDCB) tests were performed, from quasi-static loading rates up to 15 m/s, and a test rig was developed incorporating high-speed video acquisition for the high-speed tests. A detailed data reduction strategy was developed to account for (i) the types of different fracture behaviour regimes encountered, (ii) the dynamic effects in the test data, and (iii) the contribution of kinetic energy in the specimen arms to the energy balance. Using the above data reduction strategy, increasing the test rate over six decades (from 10−5 to 101 m/s) was found to lead to a reduction in the value of the adhesive fracture energy, GIc, by about 40% of its quasi-static value, i.e. from 3.5 to about 2.2 kJ/m2. Further, at quasi-static loading rates, the measured adhesive fracture energies were independent of substrate material and test geometry (i.e. DCB or TDCB). However, at faster loading rates, the TDCB tests induced higher crack velocities for a given loading rate compared with the DCB test geometry, and neither the test rate nor the crack velocity were found to be the parameter controlling the variation in GIc with increased test rate. Thus, an isothermal–adiabatic model was developed and it was demonstrated that such a model could unify the DCB and TDCB test results. Indeed, when the GIc values were plotted as a function of 1/√time, where the time was defined to be from the onset of loading the material to that required for the initiation of crack growth, the results collapsed onto a single master curve, in agreement with the isothermal–adiabatic model.  相似文献   
95.
96.
The newly proposed Z-Source inverter has been proven in the literature to exhibit both steady-state voltage buck and boost capabilities using a unique LC impedance network coupled between the power source and converter circuit. This paper now presents transient modeling and analysis of a voltage-type Z-source inverter. These aspects are found to be challenging and they need to be carefully investigated before attempting to design advanced control algorithms for controlling the Z-source inverter. Through detailed analysis, the paper identifies several phenomena on the dc and ac-sides of the inverter, which would result in the inverter having a non-minimum-phase transient response. The dc-side phenomenon is associated with the Z-source impedance network, which is shown through small-signal and signal-flow-graph analyses to be having a right-half-plane zero in its control-to-output transfer function. Also, the ac-side phenomenon is shown through space vector analysis to depend on the time intervals of inverter states used for reconstructing the desired inverter output voltage. Based on the ac vectorial analysis, a method for improving the inverter transient response is also presented. Last, simulation results obtained using a switching-functional model and experimental results obtained using a laboratory prototype are presented for validating the described theoretical concepts  相似文献   
97.
Based on an analysis of 10 patients after a feminizing operation of a virilized genital in female pseudohermaphroditism caused by congenital adrenal hyperplasia on account of 21-hydroxylase deficiency the authors emphasize in conjunction with multidisciplinary collaboration the necessity of early modification and surgical repair with adjustment of the external genital before the age of two years. An excellent anatomical and cosmetic result of reconstruction with clitoroplasty emphasizes the importance of preserving the clitoris and erectile tissue to ensure adequate social, psychic and sexual development of the patient.  相似文献   
98.
BACKGROUND: In healthy people, oral and pharyngeal epithelium preferentially carries Epstein-Barr virus (EBV) belonging to a genotype that possesses three copies of a 29 base-pair repeat in the first intron of the BZLF-1 gene, while peripheral blood mostly carries a genotype that bears two copies. Whether EBV shows differential tropism in HIV-1-coinfected hosts, who are prone to develop oral hairy leukoplakia, has not been studied. METHODS: Tongue scrapings and CD45+-enriched peripheral blood cells of 20 HIV1-infected patients and 40 healthy controls were examined. EBV-specific DNA was amplified from segments in the first intron of the BZLF-1 gene, in exon C of the LMP-1 gene, and the type A/B-specifying domain of the EBNA-3C gene. Size polymorphisms of these amplicons were assessed by agarose gel electrophoresis, and DNA sequence differences among BZLF-1 gene amplicons by single-strand conformation polymorphism analysis. RESULTS: The predominant EBV genotype in peripheral blood as well as tongue carried two copies of the BZLF-1 repeat. In controls, although the BZLF-1 genotype with two copies was exclusively detected in the blood, the genotype with three copies predominated in the tongue. The findings could not be correlated with EBV genotyped according size polymorphisms in the EBNA-3C or LMP-1 genes. DNA sequences of a proportion or all of the clones derived from the BZLF-1 amplicons in the tongues of HIV-1-infected patients were identical to those in the blood. CONCLUSIONS: These findings are consistent with EBV haematogenous superinfection of the tongue of HIV-positive individuals. Such superinfection may precede or lead to the development of oral hairy leukoplakia.  相似文献   
99.
BACKGROUND: Cardiogenic shock continues to be an ominous complication of acute myocardial infarction (AMI). Evidence from retrospective analyses, registries and observational studies suggests that aggressive management using emergent revascularization strategies can bring about significant improvement in survival in this setting. Several studies have identified age as an independent predictor of survival. OBJECTIVE: To study retrospectively the possible changes in practice patterns in the management of patients with AMI complicated by cardiogenic shock in a tertiary care referral centre, and to determine what effect these changes may have had on survival of the patients, stratified by age. METHODS: From 1989 to 1995, 115 patients fulfilled the study criteria of cardiogenic shock based on pump failure and of presenting within 48 h of onset of shock. Prespecified data were extracted from medical records. All available coronary angiograms (n = 72) were analyzed by two experienced angiographers and consensus of findings was obtained. RESULTS: The study revealed a significant increase in the use of cardiac catheterization, interventional procedures and intra-aortic balloon pump (IABP) support in patients in the age groups 65 years or less, 66 to 75 years, and older than 75 years in 1989 to 1990, through 1991 to 1992, to 1993 to 1995. Significantly fewer patients aged older than 75 years received cardiac catheterization, coronary intervention and IABP support throughout the study period and even in the final period analyzed. In-hospital survival improved from 4% in 1989-90 to 33% in 1991-92, and 44% in 1993-95 (P = 0.001). Patients aged 65 years or less improved from 10% in 1989-90 to 59% in 1993-95 (P = 0.032). Only 20% of patients aged older than 75 years survived in the 1993-95 period. By univariate analysis, use of coronary angiography (catheterization 46% versus no catheterization 5%; P < 0.0001), coronary intervention procedures (percutaneous transluminal coronary angioplasty or coronary artery bypass grafting) (intervention 48% versus no intervention 9%; P < 0.0001) and IABP support (IABP 41% versus no IABP 18%; P = 0.0096) were all associated with improved in-hospital survival. Use of thrombolytic therapy showed possible survival benefit only in patients aged older than 75 years (thrombolysis 33% versus no thrombolysis 5%; P = 0.10). Patients who underwent coronary intervention were younger (P = 0.002), had a lower incidence of previous myocardial infarction (P = 0.0002), lower heart rate (P = 0.04), higher peak creatine phosphokinase (P = 0.04) and fewer vessels with at least 70% stenosis (P < 0.0001). On multivariate analysis only lower age, lower heart rate and presence of coronary intervention procedures were found to have an independent effect on survival. CONCLUSIONS: Use of invasive treatment strategies has increased significantly since 1989-90 in the management of patients with AMI complicated by cardiogenic shock. This increase has been associated with improved in-hospital survival in all age groups except possibly the very elderly. Patients undergoing coronary interventional procedures are significantly different in baseline clinical characteristics from patients not undergoing these procedures. These observations underscore the need for randomized trials to define the optimal treatment strategies in these patients. Efficacy of invasive treatment strategies in elderly patients aged older than 75 years-deserves special attention.  相似文献   
100.
The performance of an immobilized packed-bed bioreactor for continuous ethanol fermentation was evaluated. Immobilized yeasts were prepared by entrapment in calcium alginate gel. An axial dispersed plug flow model incorporating the effects of substrate and product inhibition on fermentation kinetics was developed. The model equations were solved by the method of orthogonal collocation and the suitability of the reactor model to predict the conversions obtained in this biocatalytic reaction system was assessed.  相似文献   
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