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141.
Distributed intelligent architecture for logistics (DIAL)   总被引:4,自引:0,他引:4  
An ideal logistics problem is considered as a network flow problem which generates a logistics plan and subsequently executes the plan. A real-world logistics plan is different from its ideal counterpart modeled as a network flow problem in the sense that each node of the logistics graph is operated independently with disparate objectives. In contrast to the nodes of a network flow problem, agents are considered as software entities which embody elegant reasoning ability to justify their own actions towards individual objectives, and also interact with other agents. Hence, a group of agents or a multiagent system is best suited to solve real-world logistics problems with each agent representing a node of the graph. We have built a three-tier framework where a customer's problem can be decomposed and assigned to all the agents which together generate a logistics plan. We employ two simulation software as planning tools which enable us to simulate appropriate events. The key ideas behind this paper are large-scale multiagent architectural modeling issues (scalability), computation task control, information sharing among several customers, and a problem solving procedure before the planning process. The problem solving procedure is considered as determining the computational tasks required to be invoked to initiate the planning process. We describe the implementation of the framework.  相似文献   
142.
Plasticized polyvinyl chloride (PVC) films were prepared by melt compounding and compression molding using epoxidized cardanol (EC), a biobased plasticizer and its plasticization effect was compared with epoxidized soybean oil (ESBO) and dioctyl phthalate (DOP). The mechanical, migration, thermal, and barrier properties of the plasticized films were compared. The effect of replacing DOP with EC on the properties of PVC films was also investigated. The tensile strength, elongation at break, tensile modulus and impact strength values of PVC/EC films were higher in comparison to PVC/DOP and PVC/ESBO films at a fixed plasticizer loading of 40 wt.%. Also, the films prepared with a mixture of DOP + EC showed higher tensile strength and elongation at break compared to that of films prepared with only DOP. The PVC/EC films showed good thermal stability and reduced oxygen transmission rate (OTR) compared to PVC/DOP films. The addition of graphene and nanoclay in the PVC/plasticizer system exhibited an increase in oxygen transmission. However, the oxygen barrier property of nano filler incorporated PVC/EC films was better than PVC/DOP films. All the films showed negligible water vapor transmission rate (WVTR).  相似文献   
143.
Amino‐functionalized multi walled nanotube (MWCNT‐NH2) filled isotactic PP and isotactic‐syndiotactic (70:30) mixed PP based melt‐mixed nanocomposites have been comparatively evaluated with regard to morphological, rheological and thermo‐mechanical properties. The ratio of mean free space lengths (Lf) to infiltrated mean free space lengths (Linf) between nanotubes in isotactic‐syndiotactic (70:30) blended matrix based nanocomposites increased relatively indicating a dispersed‐morphology. The rheological percolation threshold increased up to a higher extent of MWCNT‐NH2 loading (from øc ~ 2.3 × 10?4 in isotactic to øc ~ 11 × 10?4 in iso‐syndio blend) accompanied with the formation of a mechanically responsive network structure. van‐GurpPalmen plot showed a transition in the rheological response as a consequence of network morphology getting shifted to higher concentration of MWCNT‐NH2 in the isotacticsyndiotactic mixed PP based nanocomposites than in the isotactic based one. Constitutive modeling of complex viscosity response of the nanocomposites led to functional correlation between the percolation and relaxation dynamics of polymer chains. POLYM. ENG. SCI., 58:1115–1126, 2018. © 2017 Society of Plastics Engineers  相似文献   
144.

Personal Health Record (PHR) is an online electronic application used by patients to store, retrieve and share their health information in a private and secure environment. While outsourcing the PHR into cloud environment, there exist issues in privacy while storing, searching and sharing of health information. To overcome these issues, an efficient retrieval of health records using Multi Keyword Searchable Attribute Based Encryption (MK-SABE) is proposed. To manage the increasing PHR data in the cloud, an Authorized File Level Deduplication technique is adopted. It eliminates redundant files, thereby reducing the communication overhead. Moreover, PHR data is encrypted before outsourcing and to perform searching over encrypted data, the proposed MK-SABE introduces Conjunctive Multi Keyword Searchable Attribute Based Encryption (CM-SABE). This maintains the searchable property after encryption for efficient retrieval of health files using range query. Further to ensure the trustworthiness while sharing the sensitive data, MK-SABE introduces the Location Based Encryption (LBE) and Dynamic Location Based ReEncryption (DLBRE) technique to provide additional security. From the experimental analysis, it is proved that the proposed MK-SABE reduces the storage complexity by 5%, keyword search time by 25% and improves the overall performance of PHR by 40% compared to the existing schemes.

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145.
146.
Covalent organic frameworks (COFs) are an emerging class of organic crystalline polymers with well‐defined molecular geometry and tunable porosity. COFs are formed via reversible condensation of lightweight molecular building blocks, which dictate its geometry in two or three dimensions. Among COFs, 2D COFs have garnered special attention due to their unique structure composed of two‐dimensionally extended organic sheets stacked in layers generating periodic columnar π‐arrays, functional pore space, and their ease of synthesis. These unique features in combination with their low density, high crystallinity, large surface area, and biodegradability have made them an excellent candidate for a plethora of applications ranging from energy to biomedical sciences. In this article, the evolution of 2D COFs is briefly discussed in terms of different types of chemical linkages, synthetic strategies of bulk and nanoscale 2D COFs, and their tunability from a biomedical perspective. Next, the biomedical applications of 2D COFs specifically for drug delivery, phototherapy, biosensing, bioimaging, biocatalysis, and antibacterial activity are summarized. In addition, current challenges and emerging approaches in designing 2D COFs for advanced biomedical applications are discussed.  相似文献   
147.
The comparative effect of filler combinations on the quasi-static and thermo-mechanical properties of light cured acrylate based restorative composites is addressed in the study. Two series of acrylate based restorative composites filled with hydroxyapatite (Hap) and silica/Hap combination were prepared. FTIR spectroscopy showed the filler-assisted functional interference with the chemical structure of the resin, whereas SEM–EDX revealed the state of micro-dispersion/distribution morphology of the filled composites. The silica/Hap combination filled (micro-hybrid) composites with 30 wt.-% filler showed highest compressive strength (CS) and composites with 20 wt.-% filler showed highest diametral tensile strength (DTS) as well as flexural strength (FS). Dynamic mechanical properties revealed reinforcement effectiveness correlated to extent of filler immobilization effects estimated from Kerner equation. Our study conceptually establishes the possibility of manipulating the mechanical and thermo-mechanical strength requirements, by catering to the extent of filler induced bulk hardening contributions, as characterized by immobilized volume fraction of the polymer chains. It was imperatively deduced that at very high amount of overall filler content (e.g. > 50 wt.-%) the reinforcement effectiveness is filler-controlled whereas the same extent of effectiveness may be obtained by manipulating the filler induced immobilization effects (e.g. < 20 wt. - %).  相似文献   
148.
Small levels of various dopants have a significant effect on creep in polycrystalline alumina. While most previous studies have examined the effect of ionic size, the influence of valency of dopants on creep has not yet been completely characterized. The present detailed experimental study, utilizing magnesia and zirconia with a similar ionic size, demonstrates that the ionic valency of dopants also plays a crucial role in creep since magnesia does not significantly alter creep whereas zirconia retards creep substantially. Magnesia doped alumina deforms by Coble diffusion creep whereas zirconia doped alumina deforms by an interface controlled diffusion creep process.  相似文献   
149.
Live-cell Ca2+ fluorescence microscopy is a cornerstone of cellular signaling analysis and imaging. The demand for high spatial and temporal imaging resolution is, however, intrinsically linked to a low signal-to-noise ratio (SNR) of the acquired spatio-temporal image data, which impedes on the subsequent image analysis. Advanced deconvolution and image restoration algorithms can partly mitigate the corresponding problems but are usually defined only for static images. Frame-by-frame application to spatio-temporal image data neglects inter-frame contextual relationships and temporal consistency of the imaged biological processes. Here, we propose a variational approach to time-dependent image restoration built on entropy-based regularization specifically suited to process low- and lowest-SNR fluorescence microscopy data. The advantage of the presented approach is demonstrated by means of four datasets: synthetic data for in-depth evaluation of the algorithm behavior; two datasets acquired for analysis of initial Ca2+ microdomains in T-cells; finally, to illustrate the transferability of the methodical concept to different applications, one dataset depicting spontaneous Ca2+ signaling in jGCaMP7b-expressing astrocytes. To foster re-use and reproducibility, the source code is made publicly available.  相似文献   
150.
Spinal muscular atrophy (SMA) is a severe, debilitating neuromuscular condition characterised by loss of motor neurons and progressive muscle wasting. SMA is caused by a loss of expression of SMN1 that encodes the survival motor neuron (SMN) protein necessary for the survival of motor neurons. Restoration of SMN expression through increased inclusion of SMN2 exon 7 is known to ameliorate symptoms in SMA patients. As a consequence, regulation of pre-mRNA splicing of SMN2 could provide a potential molecular therapy for SMA. In this study, we explored if splice switching antisense oligonucleotides could redirect the splicing repressor hnRNPA1 to the hnRNPA1b isoform and restore SMN expression in fibroblasts from a type I SMA patient. Antisense oligonucleotides (AOs) were designed to promote exon 7b retention in the mature mRNA and induce the hnRNPA1b isoform. RT-PCR and western blot analysis were used to assess and monitor the efficiency of different AO combinations. A combination of AOs targeting multiple silencing motifs in hnRNPA1 pre-mRNA led to robust hnRNPA1b induction, which, in turn, significantly increased expression of full-length SMN (FL-SMN) protein. A combination of PMOs targeting the same motifs also strongly induced hnRNPA1b isoform, but surprisingly SMN2 exon 5 skipping was detected, and the PMO cocktail did not lead to a significant increase in expression of FL-SMN protein. We further performed RNA sequencing to assess the genome-wide effects of hnRNPA1b induction. Some 3244 genes were differentially expressed between the hnRNPA1b-induced and untreated SMA fibroblasts, which are functionally enriched in cell cycle and chromosome segregation processes. RT-PCR analysis demonstrated that expression of the master regulator of these enrichment pathways, MYBL2 and FOXM1B, were reduced in response to PMO treatment. These findings suggested that induction of hnRNPA1b can promote SMN protein expression, but not at sufficient levels to be clinically relevant.  相似文献   
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