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31.
Proper diagnosis of comorbid disorders is crucial in treatment planning for the dually diagnosed. Since psychoactive substance use can obfuscate the diagnosis, special care must be taken to exclude organically based syndromes. Adequate periods of abstinence should first be achieved and subsequently the patient re-examined for residual symptoms compatible with a nonaddictive, nonsubstance-induced psychiatric disorder. The integration of concurrent treatment of both the mental and the addictive disorders appears to be the best approach for treatment of comorbid psychiatric and addictive disorders. An abstinence-based model that typically utilizes a 12-step group therapy is often employed for the addictive illnesses. Other forms of psychosocial therapies such as case managers are being used as well. Presently, physicians' prescribing practices for comorbid addicted patients are based on traditional approaches to use of medications in psychiatric patients, and their attitudes towards addictive disorders may play a significant role in determining the overall success of treatment. 相似文献
32.
33.
Collaborative filtering (CF) involves predicting the preferences of a user for a set of items given partial knowledge of the user's preferences for other items, while leveraging a database of profiles for other users. CF has applications e.g. in predicting Web sites a person will visit and in recommending products. Fundamentally, CF is a pattern recognition task, but a formidable one, often involving a huge feature space, a large data set, and many missing features. Even more daunting is the fact that a CF inference engine must be capable of predicting any (user-selected) items, given any available set of partial knowledge on the user's other preferences. In other words, the model must be designed to solve any of a huge (combinatoric) set of possible inference tasks. CF techniques include memory-based, classification-based, and statistical modelling approaches. Among these, modelling approaches scale best with large data sets and are the most adept at handling missing features. The disadvantage of these methods lies in the statistical assumptions (e.g. feature independence), which may be unjustified. To address this shortcoming we propose a new model-based CF method, based on the maximum entropy principle. For the MS Web application, the new method is demonstrated to outperform a number of CF approaches, including naive Bayes and latent variable (cluster) models, support vector machines (SVMs), and the (Pearson) correlation method. 相似文献
34.
A Skeleton-based Approach for Detection of Perceptually Salient Features on Polygonal Surfaces 总被引:1,自引:0,他引:1
The paper presents a skeleton‐based approach for robust detection of perceptually salient shape features. Given ashape approximated by a polygonal surface, its skeleton is extracted using a three‐dimensional Voronoi diagramtechnique proposed recently by Amenta et al. [ 3 ]. Shape creases, ridges and ravines, are detected as curvescorresponding to skeletal edges. Salient shape regions are extracted via skeleton decomposition into patches.The approach explores the singularity theory for ridge and ravine detection, combines several filtering methodsfor skeleton denoising and for selecting perceptually important ridges and ravines, and uses a topological analysisof the skeleton for detection of salient shape regions. ACM CSS: I.3.5 Computational Geometry and Object Modeling 相似文献
35.
M. K. Miller S. S. Brenner M. G. Burke 《Metallurgical and Materials Transactions A》1987,18(5):519-523
The addition of palladium to a 4130 steel reduces its sensitivity to stress corrosion cracking and to hydrogen-induced cracking.
The atom probe field-ion microscope has been used to study the microstructure and microchemistry of these palladium-modified
4130 steels with particular emphasis on the distribution of palladium between the various phases and internal interfaces.
The palladium was found to segregate to the ferrite-ferrite lath boundaries to form a mono-atomically thick adsorbate layer.
Palladium-manganese precipitates both at the lath boundaries and in the ferrite matrix were also detected. Most of the palladium
was found to remain in solution in the ferrite. 相似文献
36.
R. D. Dupuis J. C. Bean J. M. Brown A. T. Macrander R. C. Miller L. C. Hopkins 《Journal of Electronic Materials》1987,16(1):69-77
We report the results of studies which have been made on heteroepitaxial layers of GaAs and AlGaAs grown by metalorganic chemical
vapor deposition on composite substrates that consist of four different types of heteroepitaxial layered structures of Ge
and Ge-Si grown by molecular beam epitaxy on (100)-oriented Si substrates. It is found that of the four structures studied,
the preferred composite substrate is a single layer of Ge ∼1 μm thick grown directly on a Si buffer layer. The double-crystal
X-ray rocking curves of 2 μm thick GaAs films grown on such substrates have FWHM values as small as 168 arc sec. Transmission
electron micrographs of these Ge/Si composite substrates has shown that the number of dislocations in the Ge heteroepitaxial
layer can be greatly reduced by an anneal at about 750° C for 30 min which is simultaneously carried out during the growth
of the GaAs layer. The quality of the GaAs layers grown on these composite substrates can be greatly improved by the use of
a five-period GaAs-GaAsP strained-layer superlattice (SLS). Using the results of these studies, low-threshold optically pumped
AlGaAs-GaAs DH laser structures have been grown by MOCVD on MBE Ge/Si composite substrates. 相似文献
37.
Discusses ethical guidelines of the American Psychological Association regarding confidentiality in psychotherapy. Possible inconsistencies between these guidelines and privileged communication are explored. It is asserted that additional research is needed to determine the implications for psychotherapy of the ethical limitations to confidentiality and the legal restrictions on privileged communication. The relevance of moral philosophy to issues of confidentiality is considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
38.
Wang K.C. Asbeck P.M. Chang M.F. Sullivan G.J. Miller D.L. Basit H.F. 《Electronics letters》1989,25(17):1111-1112
The authors report a novel noninterfering and simple approach for evaluation of circuits implemented with AlGaAs/GaAs heterojunction bipolar transistors (HBTs). This method makes use of radiative recombination in the base region of current-carrying HBTs. The infrared radiation emitted is 'visible' to the closed-circuit TV (CCTV) cameras. Therefore, one can view the operation of the HBT circuit under test at normal biases with a TV monitor. This method can be used to determine logic states of gates, as well as collector current of individual HBTs within integrated circuits.<> 相似文献
39.
A method has been developed for the frictional assessment of powder lubricants using a shear-box tester similar to that employed by Jenike. One commercial magnesium stearate, three high-purity magnesium stearates and three high-purity magnesium palmitates were assessed using this method. Powders with a well-ordered crystal structure and particle shape have a lower initial maximum coefficient of friction μa. The difference between μa and μb, the equilibrium dynamic friction coefficient, gives an indication of lubricant film-forming propensity. The basic friction equation is obeyed by the powders for most of the load range studied but deviates slightly approaching zero normal load. 相似文献
40.
We describe planar buried heterostructure lasers which have low capacitance (lpF), large bandwidth (19GHz), high power (>20mW/facet) and high temperature operation (100°C). These lasers are very suitable for long-distance, highspeed digital and analogue signal transmission. 相似文献