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81.
In this study we apply a variant of a recently proposed linear subspace method, the Neighbourhood Component Analysis (NCA), to the task of hyperspectral classification. The NCA algorithm explicitly utilizes the classification performance criterion to obtain the optimal linear projection. NCA assumes nothing about the form of each class and the shape of the separating surfaces. In some cases we would like to weight the penalty function for different types of misclassifications of the algorithm. A modification of the NCA cost function is introduced for this case. Experimental studies are conducted on hyperspectral images acquired by two sensors: the Airborne Visible/Infrared Imaging Spectroradiometer (AVIRIS) and AISA-EAGLE. Experimental results confirm the superiority of the NCA classifier in the context of hyperspectral data classification over methodologies that were previously suggested.  相似文献   
82.
Chromosome deletion and microdeletion syndromes account for an increasing number of clinically recognizable genetic conditions. New deletion syndromes continue to be characterized, and a number of previously described syndromes are being found to be due to chromosomal deletions or microdeletions. Fluorescent in situ hybridization technologies are in wide clinical use to diagnose deletion and microdeletion syndromes, and future uses of these technologies will provide prognostic information for patients and their parents, as the genes responsible for the phenotypic aspects of various deletion syndromes are identified. Future research studies will focus on delineating critical deletion intervals at a molecular level, and identifying candidate genes for the phenotypic features of deletion and microdeletion syndromes, toward the goal of understanding the pathology of the abnormal developmental and physiologic processes involved in each syndrome.  相似文献   
83.
The broad spectrum of difficulties that exist in providing orthodontic treatment for handicapped children is well known and few practitioners offer such a service. The present article offers an analysis of the problems involved and provides some practical answers designed to overcome them. It describes some of the newer modalities that have become available to the dental profession over the last few years and shows how advantage may be gained by their exploitation, in orthodontic treatment. Additionally, some of the older and largely-forgotten methods, appropriately modified and updated, are represented in this context, where they find particular relevance. Guidelines are given to enable the orthodontic profession to gain therapeutic access to a section of the population that urgently requires treatment.  相似文献   
84.
Ti interdiffusion from the Ti/Pt/Au gate into the AlGaAs Schottky barrier layer (SBL) of 0.25-μm GaAs Pseudomorphic High Electron Mobility Transistors (PHEMTs) has been studied using the accelerated life testing technique. Based on measurements and modeling, analytical expressions for quantitative correlation between the positive pinch-off voltage (VP) shift as well as the saturation drain current (IDsat) decrease and the physical damage occurring during gate sinking has been developed. It is suggested that the main cause for device failure is the growth of the TiAs phase leading to the decrease in the SBL thickness. Additionally, it is suggested that VP may be used as a better indicator for device degradation than IDsat since it is linearly proportional to the degrading physical characteristic – the Schottky barrier layer thickness.  相似文献   
85.
86.
To detect the presence of unknown worms, we propose a technique based on computer measurements extracted from the operating system. We designed a series of experiments to test the new technique by employing several computer configurations and background application activities. In the course of the experiments, 323 computer features were monitored. Four feature-ranking measures were used to reduce the number of features required for classification. We applied support vector machines to the resulting feature subsets. In addition, we used active learning as a selective sampling method to increase the performance of the classifier and improve its robustness in the presence of misleading instances in the data. Our results indicate a mean detection accuracy in excess of 90?%, and an accuracy above 94?% for specific unknown worms using just 20 features, while maintaining a low false-positive rate when the active learning approach is applied.  相似文献   
87.
The emergence of social science research on nanotechnology   总被引:1,自引:0,他引:1  
This article examines the development of social science literature focused on the emerging area of nanotechnology. It is guided by the exploratory proposition that early social science work on emerging technologies will draw on science and engineering literature on the technology in question to frame its investigative activities, but as the technologies and societal investments in them progress, social scientists will increasingly develop and draw on their own body of literature. To address this proposition the authors create a database of nanotechnology-social science literature by merging articles from the Web of Science’s Social Science Citation Index and Arts and Humanities Citation Index with articles from Scopus. The resulting database comprises 308 records. The findings suggest that there are multiple dimensions of cited literature and that social science citations of other social scientists’ works have increased since 2005.  相似文献   
88.
    
Proteinase K-digested cell lysates from 25 Campylobacter fetus subspecies fetus and C. fetus subsp. venerealis strains were examined by SDS-PAGE and immunoblotting. Three SDS-PAGE lipopolysaccharide (LPS) profiles were observed. Two profiles were consistent with those previously reported for serogroup A and serogroup B and AB isolates and were distinguished by the relative mobility of bands in the O-chain region and by a strong reaction on immunoblots with homologous antisera. The third profile was similar but had faster migrating O-chain bands. Immunoblot reactions using homologous and heterologous adsorbed antisera showed that the O-antigen of the C. fetus subsp. fetus reference strain and other profile 2-type LPS strains was distinct from the O-antigens of strains with profile 1- or profile 3-type LPS. O-antigens of strains with profile 1- and profile 3-type LPS had shared epitopes. One strain had core components but no detectable O-antigens. Common core LPS antigens appear to be present in all strains and antibodies to common core LPS epitopes may be useful reagents for rapid detection of C. fetus.  相似文献   
89.
    
In previous works decision tree mechanisms were suggested for real-time production control of flexible manufacturing systems operating in a constant mix environment. The current paper tests the performance of a decision-treebased adaptive production control system operating in a flexible manufacturing cell in more random environments. A decision-tree-based production control system, which periodically chooses, on the basis of the current state of the system, the most appropriate scheduling rule, out of several predetermined ones, is presented. The performance of the decision-tree-based production control system was tested by simulating a flexible manufacturing cell operating in two different operational environments, distinct by the variability of their demand. The decision tree-based-production control system has performed rather well in the produce-to-order environment. However, it does not outperform the alternative scheduling rules in a highly random produce-to-order environment.  相似文献   
90.
    
Redirecting the immune system to eliminate tumor cells is a promising alternative to traditional cancer therapies, most often requiring direct interaction between an immune system effector cell and its target. Herein, a novel approach for selective attachment of malignant cells to antigen‐presenting cells by using bispecific nanoparticles is presented. The engaged cell pairs are then irradiated by a sequence of resonant femtosecond pulses, which results in widespread cell fusion and the consequent formation of hybrid cells. The dual role of gold nanoparticles as conjugating agents and fusion promoters offers a simple yet effective means for specific fusion between different cells. This technology could be useful for a variety of in vitro and in vivo applications that call for selective fusion between cells within a large heterogenic cell population.  相似文献   
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