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1.
The Quantitative Structure-Property Relationships (QSPRs) based on Graph or Network Theory are important for predicting the properties of polymeric systems. In the three previous papers of this series (Polymer 45 (2004) 3845-3853; Polymer 46 (2005) 2791-2798; and Polymer 46 (2005) 6461-6473) we focused on the uses of molecular graph parameters called topological indices (TIs) to link the structure of polymers with their biological properties. However, there has been little effort to extend these TIs to the study of complex mixtures of artificial polymers or biopolymers such as nucleic acids and proteins. In this sense, Blood Proteome (BP) is one of the most important and complex mixtures containing protein polymers. For instance, outcomes obtained by Mass Spectrometry (MS) analysis of BP are very useful for the early detection of diseases and drug-induced toxicities. Here, we use two Spiral and Star Network representations of the MS outcomes and defined a new type of TIs. The new TIs introduced here are the spectral moments (πk) of the stochastic matrix associated to the Spiral graph and describe non-linear relationships between the different regions of the MS characteristic of BP. We used the MARCH-INSIDE approach to calculate the πk(SN) of different BP samples and S2SNet to determine several Star graph TIs. In the second step, we develop the corresponding Quantitative Proteome-Property Relationship (QPPR) models using the Linear Discriminant Analysis (LDA). QPPRs are the analogues of QSPRs in the case of complex biopolymer mixtures. Specifically, the new QPPRs derived here may be used to detect drug-induced cardiac toxicities from BP samples. Different Machine Learning classification algorithms were used to fit the QPPRs based on πk(SN), showing J48 decision tree classifier to have the best performance. These results suggest that the present approach captures important features of the complex biopolymers mixtures and opens new opportunities to the application of the idea supporting classic QSPRs in polymer sciences.  相似文献   
2.
Dialysis dose and malnutrition have a great impact on the clinical out come of chronic hemodialysis patients. The interrelationships between them, however, remain undefined. Thus, we performed a study to determine the effects of increasing the dialysis dose on serum albumin concentrations and mortality in hemodialysis patients. We examined urea kinetic modeling, biochemical nutritional indices, comorbid conditions, patient survival time, and annual mortality rate. Dialysis dose, measured by Kt/V, significantly increased from 1.3 +/- 0.3 in 1987 to 1.5 +/- 0.4 in 1990 and to 1.7 +/- 0.4 in 1993. Serum albumin level also increased from 3.8 +/- 0.4 g/dL in 1987 to 4.0 +/- 0.4 in 1990 and to 1.7 +/- 0.4 in 1993. In 1993, 76% of patients had Kt/V > or = 1.50 compared with 45% in 1990 and 28% in 1987, whereas 82% of patients had a serum albumin level > or 4.0 g/dL in 1993 compared with 58% in 1990 and 29% in 1987. Protein catabolic rate and hematocrit also increased from 1987 to 1993, but not serum cholesterol or triglyceride. The annual mortality rate declined from 16.1% in 1987 to 13.2% in 1990 and to 8.0% in 1993. The decrease in mortality appeared to be unrelated to differences in patient selection or comorbid conditions. Serum albumin levels, hematocrit, Kt/V, and protein catabolic rate were significantly related to patient survival after age, sex, and diabetic status had been adjusted. Furthermore, there was a positive correlation between Kt/Vs and serum albumin concentration (r = 0.216, P < 0.001). Thus it appears that increasing the dose of dialysis improves serum albumin levels and perhaps survival rate in hemodialysis patients as well.  相似文献   
3.
4.

Background and purpose

Adverse events and medical errors can have severe consequences for patients (“first victims”), but also for the involved health care professionals (“second victims”). Don Berwick, former director of the Boston Institute for Healthcare Improvement (USA), highlighted the support for “second victims” as an “ethical issue”. But there is no clarity about what “ethical issue” implies. This article aims to clarify this question from the perspective of organizational ethics.

Method

Starting with data from the literature, challenges are described and evaluated from the perspective of organizational ethics.

Results

Evidence suggests that current approaches for supporting “second victims” are not sufficiently effective to help professionals to cope with the psychological consequences of adverse patient events and medical errors. This not only has negative consequences for the involved professionals, but can also put patient safety again at risk. In the light of these data, an organizational ethics approach is needed to comply with Don Berwick’s claim to consider the support of “second victims” as an “ethical issue”. This approach fosters the congruence of the organization’s values that are declared and those that are practiced. Its normative foundation is rooted in the organization’s duty of care both for the patients and for the employees.

Conclusions

Using organizational ethics it is possible to conceptualize and visualize the support for “second victims” as a binding component of the safety culture of the organization. It is translated into the organization’s obligation to raise the awareness for the phenomenon and to provide the resources necessary to deal effectively with it, e.?g., evidence-based ethical guidelines, standardized procedures, staff training, and low-threshold coaching programs.
  相似文献   
5.
Distributed video coding (DVC) constitutes an original coding framework to meet the stringent requirements imposed by uplink-oriented and low-power mobile video applications. The quality of the side information available to the decoder and the efficiency of the employed channel codes are primary factors determining the success of a DVC system. This contribution introduces two novel techniques for probabilistic motion compensation in order to generate side information at the Wyner-Ziv decoder. The employed DVC scheme uses a base layer, serving as a hash to facilitate overlapped block motion estimation at the decoder side. On top of the base layer, a supplementary Wyner-Ziv layer is coded in the DCT domain. Both proposed probabilistic motion compensation techniques are driven by the actual correlation channel statistics and reuse information contained in the hash. Experimental results report significant rate savings caused by the novel side information generation methods compared to previous techniques. Moreover, the compression performance of the presented DVC architecture, featuring the proposed side-information generation techniques, delivers state-of-the-art compression performance.  相似文献   
6.
Experimental validation of numerical models developed by the authors to predict the static behaviour of microelectrostatic actuators is described. Cantilever microbeams, currently used in connection with RF-MEMS and micro-scale material testing were analysed. A set of microcantilevers, bending in the plane of the wafer, i.e. in the same plane as the profiling system’s target, was tested. This differs from the popular case of out-of-plane microbeams, usually studied in the literature. Geometry nonlinearity caused by large deflection of the microbeam was investigated and nonlinear coupled formulation of electromechanical equilibrium was performed. Coupled-field analysis was implemented using the Finite Element Method (FEM), to predict displacements and pull-in voltage measured by Fogale Zoomsurf 3D, subsequently plotting the displacement-versus-voltage curve to complete model validation. FEM nonlinear analysis, based on iterative approach with mesh morphing, and FEM non-incremental approach, including a special element proposed by the authors, are compared to the linear solution and to experimental results. Geometry nonlinearity appears relevant in microbeam modelling and requires a nonlinear solution of the coupled problem. Investigative work, which compared the results of 2D and 3D models to experimental data, revealed that some three dimensional effects are significant in model validation, but the 2D approach may be effective in predicting static behaviour provided that at least a microbeam thickness equivalent is adopted.  相似文献   
7.
We consider a simply supported plate with constant thickness, defined on an unknown multiply connected domain. We optimize its shape according to some given performance functional. Our method is of fixed domain type, easy to be implemented, based on a fictitious domain approach and the control variational method. The algorithm that we introduce is of gradient type and performs simultaneous topological and boundary variations. Numerical experiments are also included and show its efficiency.  相似文献   
8.
Machining dynamic stability has been enhanced through a damping coating based on a novel carbon-based nanocomposite material. The coating was synthesized using a plasma enhanced chemical vapor deposition method, and deposited on to the round-shank boring bar used for internal turning and tested during machining. Comparisons between an uncoated and a coated boring bar were carried out at 0.25 mm and 0.5 mm depth of cut using a five times length to diameter ratio overhang, which are typical conditions known to generate detrimental mechanical vibrations. From sound pressure measurement it was found that the measured absolute sound level during process could be reduced by about 90% when using the tool coated with damping layer. Surface roughness measurements of the processed workpiece showed decreased Ra values from approximately 3-6 μm to less than 2 μm (and in 50% of the cases <1 μm) when comparing an uncoated standard tool with its coated counterpart. Moreover, it was found that the addition of an anti-vibration coating did not adversely affect other tool properties, such as rigidity and modularity.  相似文献   
9.
BACKGROUND: Cerebral circulation delivers the blood flow to the brain through a dedicated network of sanguine vessels. A healthy human brain can regulate cerebral blood flow (CBF) according to any physiological or pathological challenges. The brain is protected by its self-regulatory mechanisms, which are dependent on neuronal and support cellular populations, including endothelial ones, as well as metabolic, and even myogenic factors. OBJECTIVES: Accumulating data suggest that “non-pharmacological” approaches might provide new opportunities for stroke therapy, such as electro-/acupuncture, hyperbaric oxygen therapy, hypothermia/cooling, photobiomodulation, therapeutic gases, transcranial direct current stimulations, or transcranial magnetic stimulations. We reviewed the recent data on the mechanisms and clinical implications of these non-pharmaceutical treatments. METHODS: To present the state-of-the-art for currently available non-invasive, non-pharmacological-related interventions in acute ischemic stroke, we accomplished this synthetic and systematic literature review based on the Preferred Reporting Items for Systematic Principles Reviews and Meta-Analyses (PRISMA). RESULTS: The initial number of obtained articles was 313. After fulfilling the five steps in the filtering/selection methodology, 54 fully eligible papers were selected for synthetic review. We enhanced our documentation with other bibliographic resources connected to our subject, identified in the literature within a non-standardized search, to fill the knowledge gaps. Fifteen clinical trials were also identified. DISCUSSION: Non-invasive, non-pharmacological therapeutic/rehabilitative interventions for acute ischemic stroke are mainly holistic therapies. Therefore, most of them are not yet routinely used in clinical practice, despite some possible beneficial effects, which have yet to be supplementarily proven in more related studies. Moreover, few of the identified clinical trials are already completed and most do not have final results. CONCLUSIONS: This review synthesizes the current findings on acute ischemic stroke therapeutic/rehabilitative interventions, described as non-invasive and non-pharmacological.  相似文献   
10.
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