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1.
The Dynamic Reference (DR) method has been developed for subjective image quality experiments in which original or undistorted images are unavailable. The DR method creates reference image series from test images. Reference images are presented to observers as a slide show prior to evaluating their quality. As the observers view the set of reference images, they determine the overall variation in quality within the set of test images. This study compared the performance of the DR method to that of the standardized absolute category rating (ACR) and paired comparison (PC) methods. We measured the performance of each method in terms of time effort and discriminability. The results showed that the DR method is faster than the PC method and more accurate than the ACR method. The DR method is especially suitable for experiments that require highly accurate results in a short time.  相似文献   
2.
Measured data and simulation results for a two-channel experimental switched-reluctance-motor (SRM)-based aircraft engine starter/generator system are presented. The two channels of the system provide power to two separate and independent loads. The results presented document the performance capability of this system with both channels operating simultaneously. Both measured and predicted system performance are presented and compared. In addition, operating characteristics that are unique to this SRM-based system are described. Of particular interest are the interactions between the two separate channels when one channel experiences a load transient and the other channel does not. The source of channel interactions is described, and measured data is provided. The issue of clearing load faults is also addressed. Design results for adding this capability to the experimental system are described  相似文献   
3.
Jeremic A  Jin Cho W  Jena BP 《Ultramicroscopy》2006,106(8-9):674-677
Secretion is one of the most fundamental cellular processes. Porosomes have been demonstrated as the universal secretory machinery in cells. Earlier studies determine the presence of a number of proteins in porosomes, among them the N- and P/Q-type calcium channels, actin, syntaxin-1, synaptotagmin-1, vimentin, the N-ethylmaleimide-sensitive factor (NSF), the chloride channel CLC-3, and the alpha subunit of the heterotrimeric GTP-binding protein G(o). Studies demonstrate that t-SNAREs localize at the base of porosomes, and directly interact with calcium channels. In the present study, we demonstrate that Syntaxin-1 co-localizes with cholesterol in solubilized synaptosomal membrane preparations. Depletion of cholesterol, results in the dissociation of both Syntaxin-1 and N-type calcium channel from neuronal porosomes. Thus, cholesterol participates as an integral component of the neuronal porosome complex, and is required for its stability.  相似文献   
4.
A lightweight and low-cost current sensor for application in high-current, high-frequency inverters and power converters is described. The current sensor consists of three elements. The first is a Rogowski coil, also known as a Maxwell Worm, which is a nonmagnetic toroid wound like an inductor. The output voltage at the open terminals of this winding is proportional to the time derivative of the current flowing in a conductor passing through the toroid. The second element of the sensor is an integrator which has as its input the output of the Rogowski coil. The third element of the sensor is a circuit to reset the integrator to zero whenever the current through the Rogowski coil is known to be zero. Resetting the integrator prevents the error generated by the integration of offset voltages and biases, which cannot be avoided in practical integrators, from becoming unacceptably large. For the case of a semiconductor switch, the current through the switch is known to be zero when the switch is gated off. The results presented using this current sensing scheme demonstrate its feasibility for use in high-power motor drive applications. The sensor has its largest advantage for measuring currents with peak values greater than 50 A and with switching frequencies greater than 1 kHz  相似文献   
5.
Locally advanced non-small cell lung carcinoma (NSCLC) presents enormous challenges to clinicians and researchers. Because of the absence of metastatic disease, it is a potentially curable condition, greatly differentiating it from stage IV NSCLC. The median and actuarial survival rates are poor, though clearly improved in the past decade, and clearly better than several other types of locally advanced malignancies (e.g., pancreatic cancer, glioblastoma). As demonstrated in Table I, the combination of chemotherapy and radiotherapy has earned the designation of "standard of care" for most good-performance-status patients with locally advanced NSCLC. It is likely that improvements in radiotherapy have also contributed to the enhanced survival and local control rates in this disease. With concurrent chemoradiotherapy, the majority of patients can receive a substantial local response (Fig. 1). Many achieve durable local control, only to succumb to eventual distant metastatic failure. There remains much room for improvement, and there are several avenues for clinical and translational research that offer promise. These include new systemic chemotherapy options (and newer ways of combining these drugs with radiotherapy), improvements in radiotherapy fractionation and dose intensity, methods of protection from chemoradiotherapy toxicity, specific therapies to prevent brain metastatic failure, and the integration of biologically targeted molecules into chemoradiation programs. This article summarizes the advances in the treatment of locally advanced NSCLC over the past several decades and explores some of the many remaining controversies and areas for future investigation.  相似文献   
6.
We develop methods for automatic detection and localization of landmines using chemical sensor arrays and statistical signal processing techniques. The transport of explosive vapors emanating from buried landmines is modeled as a diffusion process in a two-layered system consisting of ground and air. Measurement and statistical models are then obtained from the associated concentration distribution. We derive two detectors (the generalized likelihood ratio (GLR) test and the mean detector) and determine their performance in terms of the probabilities of false alarm and detection. To determine the unknown location of a landmine, we derive a maximum likelihood (ML) estimation algorithm and evaluate its performance by computing the Cramer-Rao bound (CRB). The results are applied to the design of chemical sensor arrays, satisfying criteria specified in terms of detection and estimation performance measures and for optimally selecting the number and positions of sensors and the number of time samples. To illustrate the potential of the proposed techniques in a realistic demining scenario, we derive a moving-sensor algorithm in which the stationary sensor array is replaced by a single moving sensor. Numerical examples are given to demonstrate the applicability of our results  相似文献   
7.
8.
The distribution of estrogen and progesterone receptors (ER, PR) was assessed in the primary tumour in 1335 of 2704 (49%) consecutive new breast carcinoma patients (HORMREC). In a subgroup of 757 radically treated patients without systemic adjuvant treatment (RADOP) the relation of the ER and PR content to relapse and survival was evaluated. Three levels were defined for ER: ER-: <10 fmol/mg protein, ER+: moderate ER content >/= 10-99 fmol/mg protein, and high ER content >/= 100 fmol/mg protein. In 1288 patients of the HORMREC group who were evaluable for ER, 1061 (82%) had ER+ tumours, 685 (65%) of moderate content and 376 (35%) of high content, respectively. Among 917 patients, evaluable for PR, 723 (79%) tumours were PR+ (>/= 20 fmol/mg protein), of them 352 (49%) with a moderate content (>/= 20-99 fmol/mg protein) and 371 (51%) with a high content ( >/= 100 fmol/mg protein). The median ER content was significantly increased among the post-menopausal women as compared to the premenopausal women, whereas the median PR content showed no such differences. For the RADOP patients, no correlation between ER status and the first site of relapse was seen, whereas PR+ tumours tended to relapse more often locally than PR- tumours. In the univariate analysis the five-and 10-year tumour-related survival rates for all patients were not correlated with ER or PR positivity. One subgroup of patients with favourable outcome was identified on the basis of hormone receptors: Premenopausal women with tumours of moderately elevated ER content. In the multivariate analysis tumour size and axillary node status were the only independent predictors of survival. Measurements of hormone receptor status give weak prognostic information in radically treated patients with breast cancer as long as no adjuvant systemic treatment is applied. As todays' adjuvant treatment is based on the knowledge of hormone receptor status of the primary tumour, this information should be obtained routinely.  相似文献   
9.
In a prepilot study, eight adults with chronic PTSD underwent three 90-minute sessions of eye movement desensitization and reprocessing (EMDR) at one-week intervals in an open trial. None of the seven who completed treatment met criteria for current PTSD two months later. Significant decreases in measures of pathology and disturbance were recorded. A controlled trial of EMDR is under way.  相似文献   
10.
European Journal of Wood and Wood Products - Compatibility between preservative and resin plays an important role in determining the adhesive performance of preservative-treated engineered wood...  相似文献   
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