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101.
Active shape models bear a great promise for model-based medical image analysis. Their practical use, though, is undermined due to the need to train such models on large image databases. Automatic building of point distribution models (PDMs) has been successfully addressed and a number of autolandmarking techniques are currently available. However, the need for strategies to automatically build intensity models around each landmark has been largely overlooked in the literature. This work demonstrates the potential of creating intensity models automatically by simulating image generation. We show that it is possible to reuse a 3D PDM built from computed tomography (CT) to segment gated single photon emission computed tomography (gSPECT) studies. Training is performed on a realistic virtual population where image acquisition and formation have been modeled using the SIMIND Monte Carlo simulator and ASPIRE image reconstruction software, respectively. The dataset comprised 208 digital phantoms (4D-NCAT) and 20 clinical studies. The evaluation is accomplished by comparing point-to-surface and volume errors against a proper gold standard. Results show that gSPECT studies can be successfully segmented by models trained under this scheme with subvoxel accuracy. The accuracy in estimated LV function parameters, such as end diastolic volume, end systolic volume, and ejection fraction, ranged from 90.0% to 94.5% for the virtual population and from 87.0% to 89.5% for the clinical population.   相似文献   
102.
Antioxidant and antibacterial activity of a methanol rosemary extract (RE) containing 30% carnosic acid (CA), 16% carnosol (COH) and 5% rosmarinic acid (RA) was studied in vitro alone and in combination with the antioxidant food additives butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA). The antioxidant efficiency of the extract, CA, and RA, was determined by a kinetic analysis of the 2,2-diphenyl-2-picrylhydrazyl hydrate radical (DPPH·) scavenging activity. RE showed two different rate slopes in the reduction of DPPH· vs. time curve, which correlated with the distinct behaviours of RA and CA; pure RA reached the plateau more rapidly than CA. A synergistic antioxidant effect between RE and BHT was demonstrated by isobolographic analysis and a synergistic interaction of RE with BHA to inhibit Escherichia coli and Staphylococcus aureus growth was observed. Therefore, rosemary not only enhances the antioxidant efficiency of BHA and BHT, but also the antibacterial effect of BHA; allowing a decrease from 4.4 to17 folds in the amounts of the synthetic compounds used.  相似文献   
103.
104.
A comprehensive group intervention with 124 children who experienced disaster-related trauma during a massive flood in Santa Fe, Argentina, in 2003 is illustrated, utilizing a one-session group eye movement desensitization and reprocessing (EMDR) protocol. A posttreatment session was done 3 months after the treatment intervention to evaluate results. Results of this one-session treatment procedure, utilizing the EMDR-Integrative Group Treatment Protocol, showed statistically significant reduction of symptoms immediately after the intervention. These statistically significant differences were sustained at posttreatment evaluation 3 months later, as measured by psychometric scales, and by clinical and behavioral observation. Data analysis also revealed significant gender differences. Despite methodological limitations, this study supports the efficacy of EMDR group treatment in the amelioration and prevention of posttraumatic stress disorder symptoms, providing an efficient, simple, and economic (in terms of time and resources) tool for disaster-related trauma. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
105.
Developing GIS Applications with Objects: A Design Patterns Approach   总被引:1,自引:0,他引:1  
In this paper we present an object-oriented approach for designing GIS applications; it combines well known software engineering practices with the use of design patterns as a conceptual tool to cope with recurrent problems appearing in the GIS domain. Our approach allows the designer to decouple the conceptual definition of application objects from their spatial representation. In this way, GIS applications can evolve smoothly, because maintenance is achieved by focusing on different concerns at different times. We show that our approach is also useful to support spatial features in conventional applications built with object-oriented technology. The structure of this paper is as follows: We first introduce design patterns, an efficient strategy to record design experience; then we discuss the most common design problems a developer of GIS applications must face. The core of our method is then presented by explaining how the use of decorators helps in extending objects to incorporate spatial attributes and behavior. Next, we analyze some recurrent design problems in the GIS domain and present some new patterns addressing those problems. Some further work is finally discussed.  相似文献   
106.
Storing Matter is a new analytical technique for organic and inorganic materials, which tries to circumvent the well-known matrix effect in SIMS. This technique consists of separating the sputtering of the sample from the subsequent analysis steps. Thus, the sample to be analysed is sputtered with a focused ion beam produced by a floating low-energy ion gun (FLIG) and the particles emitted under the ion impacts are deposited at a sub-monolayer level on a well-known collector. The collector with the deposited material is then analysed in a second step by SIMS (dynamic and static mode). The main advantage of this new technique is to improve the sensitivity and the quantification of the SIMS analysis. All the processes, including all the sample and collector transfers, are performed in UHV conditions. This paper presents preliminary results obtained on the Storing Matter prototype instrument developed in our laboratory. The sputtering of a (1 0 0) Ge wafer by ions was used as a model system to study the influence of using different collector surfaces (W, Ta and Al) on the Storing Matter useful yield.  相似文献   
107.
3D Curves Reconstruction Based on Deformable Models   总被引:2,自引:0,他引:2  
We present a new method, based on curve evolution, for the reconstruction of a 3D curve from two different projections. It is based on the minimization of an energy functional. Following the work on geodesic active contours by Caselles et al. (in Int. Conf. on Pattern Recognition, 1996, Vol. 43, pp. 693–737), we then transform the problem of minimizing the functional into a problem of geodesic computation in a Riemann space. The Euler-Lagrange equation of this new functional is derived and its associated PDE is solved using the level set formulation, giving the existence and uniqueness results. We apply the model to the reconstruction of a vessel from a biplane angiography.  相似文献   
108.
Objective: This study proposed the development of oral lyophilisates with respect to pediatric medicine development guidelines, by applying risk management strategies and DoE as an integrated QbD approach.

Methods: Product critical quality attributes were overviewed by generating Ishikawa diagrams for risk assessment purposes, considering process, formulation and methodology related parameters. Failure Mode Effect Analysis was applied to highlight critical formulation and process parameters with an increased probability of occurrence and with a high impact on the product performance. To investigate the effect of qualitative and quantitative formulation variables D-optimal designs were used for screening and optimization purposes.

Results: Process parameters related to suspension preparation and lyophilization were classified as significant factors, and were controlled by implementing risk mitigation strategies. Both quantitative and qualitative formulation variables introduced in the experimental design influenced the product’s disintegration time, mechanical resistance and dissolution properties selected as CQAs. The optimum formulation selected through Design Space presented ultra-fast disintegration time (5?seconds), a good dissolution rate (above 90%) combined with a high mechanical resistance (above 600?g load).

Conclusions: Combining FMEA and DoE allowed the science based development of a product with respect to the defined quality target profile by providing better insights on the relevant parameters throughout development process. The utility of risk management tools in pharmaceutical development was demonstrated.  相似文献   
109.
This paper deals with the estimation and prediction problems of spatio-temporal processes by using state-space methodology. The spatio-temporal process is represented through an infinite moving average decomposition. This expansion is well known in time series analysis and can be extended straightforwardly in space–time. Such an approach allows easy implementation of the Kalman filter procedure for estimation and prediction of linear time processes exhibiting both short- and long-range dependence and a spatial dependence structure given on the locations. Furthermore, we consider a truncated state-space equation, which allows to calculate an approximate likelihood for large data sets. The performance of the proposed Kalman filter approach is evaluated by means of several Monte Carlo experiments implemented under different scenarios, and it is illustrated with two applications.  相似文献   
110.
The AA. present a retrospective study of all instances diagnosed as mucoceles in the last 15 years (1978-1993) at General University Hospital, Valle de Hebrón. Age of occurrence and sex, foregoing pathologic history, clinical picture, diagnostic tests, treatment and subsequent course of the condition are duly considered and appraised. Our attempt has been to stablish a diagnostic clinical pattern of these conditions, which generally are uncovered through its complications.  相似文献   
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