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41.
A modified form of Carey'ls method for predicting the heat transfer to a turbulent falling film is presented. The new model is successfully tested against experimental data as well as other models. This method utilizes an optimization technique along with the Rombcrg integration to determine two universal constants for the modified turbulent diffusivisity model. The results show that in spite of its relative simplicity, the new model is a fairly accurate one, having an overall average error of less than 9%.  相似文献   
42.
We present a scaling methodology to improve iDDT fault coverage in random logic circuits. The study targets two iDDT test methods: Double Threshold iDDT and Delayed iDDT. The effectiveness of the scaling methodology is assessed through physical test measurements, and studied relative to process variation and impact on circuit performance. The scaling is made possible using a clustering methodology that can significantly improve fault coverage. The results show that without clustering, the effectiveness of the iDDT testing methods considered is greatly reduced as the circuit size increases. Editor: Z Li Ali Chehab received his Bachelor degree in EE from the American University of Beirut (AUB) in 1987, the Master’s degree in EE from Syracuse University, and the PhD degree in ECE from the University of North Carolina at Charlotte, in 2002. From 1989 to 1998, he was a lecturer in the ECE Department at AUB. He rejoined the ECE Department at AUB as an assistant professor in 2002. His research interests are VLSI design and test, mobile agents, and wireless security. Rafic Makki is currently serving as Dean of the College of Information Technology at UAE University. Rafic began his career with the University of North Carolina at Charlotte in 1984, serving the university for a period of 19 years. Rafic is the recipient of several awards including the 2005 IBM Faculty Research Award (first in the Middle-East), the 2002 First Citizen Research Scholar Medal, and the ALCOA Outstanding Graduate Faculty Award. Rafic received a PhD in Electrical Engineering in 1983 from Tennessee Tech University. His research interests include design for testability and defect-based testing.  相似文献   
43.
Editorial     
Mobile Networks and Applications -  相似文献   
44.
Recently, cytokine gene transfer into tumour cells has been shown to mediate tumour regression in animal models via immunomodulation. Consequently, a number of clinical protocols have been developed to treat cancer patients with cytokine gene-modified tumour cells. Here, we report the results of a clinical phase I trial using for the first time autologous, interleukin 7 gene-modified tumour cells for vaccination of ten patients with disseminated malignant melanoma. Melanoma cells were expanded in vitro from surgically removed metastases, transduced by a ballistic gene transfer technique and were then injected after in vitro irradiation s.c. at weekly intervals. Clinically, there was no major toxicity except for mild fever, and no major clinical response towards vaccination was observed. Eight of ten patients completed the initial three s.c. vaccinations and were eligible for immunological evaluation. Post vaccination, peripheral mononuclear cells (PBMCs) were found to contain an increased number of tumour-reactive proliferative as well as cytolytic cells, as determined by a limiting dilution analysis. In three of six patients, the frequencies of anti-melanoma cytolytic precursor cells increased between 2.6- and 28-fold. Two of these patients showed a minor clinical response. Analysis of the autologous tumour cell vaccines regarding IL-7 secretion after gene transfer, HLA class I and class II cell surface expression, secretion of immunosuppressive mediators (TGF-beta1, IL-10) and various melanoma-associated tumour antigens revealed a very diverse expression profile. In conclusion, vaccination using gene-modified autologous melanoma cells induced immunological changes in a group of advanced, terminally ill patients. These changes can be interpreted as an increased anti-tumour immune response. However, immunological modulation was most pronounced in patients in good physical condition. Therefore, patients with minimal tumour load or minimal residual disease might preferentially benefit from tumour cell vaccination in further studies. In order to evaluate the effects of the cytokine gene-modified tumour cell vaccines more precisely, an antigenically better defined vaccine is needed.  相似文献   
45.
The vasopressin (VP)-containing projections from the cells of the bed nucleus of the stria terminalis to the lateral septum (LS) are sexually dimorphic and dependent on gonadal steroids. Recently, the difference in VP distribution found among both sexes was also demonstrated in male mice genetically selected for different levels of intermale aggression. In the present study we examined whether this differential VP distribution in males also exists in an outbred strain of wild-type rats. After the animals were tested for their level of aggression, the VP content and the fiber density of the LS were measured using radioimmunoassay and immunocytochemistry, respectively. In addition, basal levels of plasma testosterone (T) were measured. Both biochemical data and immunocytochemical data revealed a negative correlation between VP and intermale aggression. Aggressive rats exhibited low levels of VP whereas intermediate and nonaggressive animals showed higher levels. Differences in adult levels of T were not found. The results are in accordance with the observations previously found in male mice, reconfirming the correlation between lateral septal VP and aggression.  相似文献   
46.
The pay-TV industry seeks to extend its reach to portable display devices. At the same time, it seeks to ensure a horizontal market by making interoperable the Conditional Access Systems (CASs) employed to protect content. To achieve interoperability for such devices, this paper proposes a form of selective encryption for video that allows simultaneous distribution of a small percentage of video data on a per-CAS basis, allowing sharing of the unencrypted video between the CASs. The bitrate overhead for each additional CAS enabled is found to be on average 7.41 %, whereas the computational overhead amounts to no more than 40 ms for the benchmark sequences tested. Adaptation of CAS to transparent encryption of scalable video is also demonstrated in this paper.  相似文献   
47.
48.
Wireless sensor network (WSN) data is often subjected to corruption and losses due to wireless medium of communication and presence of hardware inaccuracies in the nodes. For a WSN application to deduce an appropriate result it is necessary that the data received is clean, accurate, and lossless. WSN data cleaning systems exploit contextual associations existing in the received data to suppress data inconsistencies and anomalies. In this work we attempt to clean the data gathered from WSN by capturing the influence of changing dynamics of the environment on the contextual associations existing in the sensor nodes. Specifically, our work validates the extent of similarities among the sensed observations from contextually (spatio‐temporally) associated nodes and considers the time of arrival of data at the sink to educate the cleaning process about the WSN's behavior. We term the data cleaning technique proposed in this work as time of arrival for data cleaning (TOAD). TOAD establishes belief on spatially related nodes to identify potential nodes that can contribute to data cleaning. By using information theory concepts and experiments on data sets from a real‐time scenario we demonstrate and establish that validation of contextual associations among the sensor nodes significantly contributes to data cleaning. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
49.
In this article, the condition assessment of a cable-stayed bridge using remote sensing is presented. The displacement influence line (DIL) of the bridge under the live load tests is measured for a discrete number of target points. Three different remote sensing techniques including, laser scanning, terrestrial robotic total station and digital levelling are adopted for this purpose. It is demonstrated that DIL obtained by non-contact system is capable of identifying an emulated damage in an actual operating system. The contribution of the work is fourfold. First, a damage index based on the displacement profile of the bridge under the weigh-in-motion is extracted from the non-contact sensing system. Second, our study compares three different remote sensing techniques, namely, digital levelling, robotic total station and laser scanning and uses the measurements to validate the finite element model. Third, the effectiveness of the proposed method for structural damage identification is validated in a real-world large-scale operating structure. Finally, it is validated that strain-based influence line is highly likely to misidentify damage especially when the location of damage is not in the close proximity of the sensor; however, DIL is a better damage indicator even if damage occurs far from the measurement point.  相似文献   
50.

It has long been reported that children with autism spectrum disorder (ASD) exhibit attention difficulties while learning. They tend to focus on irrelevant information and can easily be distracted. As a result, they are often confined to a one-to-one teaching environment, with fewer distractions and social interactions than would be present in a mainstream educational setting. In recent years, inclusive mainstream schools have been growing in popularity due to government policies on equality rights. Therefore, it is crucial to investigate attentional patterns of children with ASD in mainstream schools. This study aims to explore the attentional behaviors of children with ASD in a virtual reality simulated classroom. We analyzed four eye-gaze behaviors and performance scores of 45 children: children with ASD (ASD n = 20) and typically developing children (TD n = 25) when performing attention tasks. The gaze behaviors included time to first fixate (TTFF), first fixation duration (FFD), average fixation duration (AFD) and the sum of fixation count (SFC) on fourteen areas of interest (AOIs) in the classroom. Our results showed that children with ASD exhibit similar gaze behaviors to TD children, but with significantly lower performance scores and SFC on the target AOI. These findings showed that classroom settings can influence attentional patterns and the academic performance of children with ASD. Further studies are needed on different modalities for supporting the attention of children with ASD in a mainstream setting.

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