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Automated techniques for Arabic content recognition are at a beginning period contrasted with their partners for the Latin and Chinese contents recognition. There is a bulk of handwritten Arabic archives available in libraries, data centers, historical centers, and workplaces. Digitization of these documents facilitates (1) to preserve and transfer the country’s history electronically, (2) to save the physical storage space, (3) to proper handling of the documents, and (4) to enhance the retrieval of information through the Internet and other mediums. Arabic handwritten character recognition (AHCR) systems face several challenges including the unlimited variations in human handwriting and the leakage of large and public databases. In the current study, the segmentation and recognition phases are addressed. The text segmentation challenges and a set of solutions for each challenge are presented. The convolutional neural network (CNN), deep learning approach, is used in the recognition phase. The usage of CNN leads to significant improvements across different machine learning classification algorithms. It facilitates the automatic feature extraction of images. 14 different native CNN architectures are proposed after a set of try-and-error trials. They are trained and tested on the HMBD database that contains 54,115 of the handwritten Arabic characters. Experiments are performed on the native CNN architectures and the best-reported testing accuracy is 91.96%. A transfer learning (TF) and genetic algorithm (GA) approach named “HMB-AHCR-DLGA” is suggested to optimize the training parameters and hyperparameters in the recognition phase. The pre-trained CNN models (VGG16, VGG19, and MobileNetV2) are used in the later approach. Five optimization experiments are performed and the best combinations are reported. The highest reported testing accuracy is 92.88%.

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2.
The effects of NS 1619, a newly developed activator of large-conductance Ca2+-activated K+ channels, were investigated on single smooth muscle fibers dissociated enzymatically from rat vas deferens and on contractions of the epididymal half of vas deferens. K+ currents were recorded using whole-cell patch-clamp methods in near-physiological K+ solutions (5.4 mM extracellular K+/145 mM intracellular K+). When cell membrane voltage was stepped to test potentials (-60 to +60 mV) from a holding potential of -10 mV, NS 1619 increased the outwardly rectifying K+ current in a concentration-dependent manner. The increased portion of the K+ current by NS 1619 was totally abolished by charybdotoxin (100 nM) but not by glibenclamide (3 microM). NS 1619 reduced electrically stimulated contractile responses of rat vas deferens in a concentration-dependent manner, and charybdotoxin but not glibenclamide partially inhibited the effect of NS 1619. NS 1619 (50 microM) inhibited the noradrenaline-induced contraction. Charybdotoxin (100 nM) partially reduced the NS 1619-induced inhibition while glibenclamide (3 microM) had no effect. NS 1619 (10-100 microM) reduced the high K+-induced contractions in a noncompetitive manner. The present results indicate that NS 1619 activates charybdotoxin-sensitive Ca2+-activated K+ channels and probably inhibits Ca2+ influx. These two effects might account largely for the observed mechanical inhibition induced by NS 1619 in the epididymal half of isolated rat vas deferens.  相似文献   
3.
Network security devices such as firewalls and intrusion detection systems are constantly updated in their implementation to accommodate new features, performance standards and to utilize new hardware optimization. Reliable, yet practical, testing techniques for validating the configuration enforcement after every new software and firmware update become necessary to assure correct configuration realization. Generating random traffic to test the firewall configuration enforcement is not only inaccurate but also impractical as it requires an infeasible number of test cases for a reasonable testing coverage. In addition, in most cases the policies used during testing are manually generated or have limited configuration profiles. We present a framework for automatic testing of the firewall configuration enforcement using efficient and flexible policy and traffic generation. In a typical test session, a large set of different policies are generated based on the access-control list (ACL) grammar and according to custom profiles. Test packets are generated to particularly consider critical segments of the tested policies and to achieve high coverage of the testing space. We also describe our implementation of a fully-automated framework, which includes ACL grammar modeling, the policy generation, test cases generation, capturing and analyzing firewall output, and creating detailed test reports. Our evaluation results show that our security configuration testing is not only achievable but it also offers high coverage with significant degree of confidence.  相似文献   
4.
This paper describes a stereophotogrammetry method that reconstructs 3D microstructure surfaces from Scanning Electron Microscope (SEM) images. The microstructure surfaces are represented as 3D meshes with texture. The method's algorithm is based on the following stages: a) computing 3D points from 2D matched points; b) triangulating the 3D points into a 3D mesh; and c) mapping a 2D image as a texture on the surface. The textured 3D surface exhibits very realistic 3D microstructure surfaces for 3D visualization and engineering analysis. The performance of the proposed method has been analyzed and demonstrated on a variety of materials and complex geometries.  相似文献   
5.
This study investigated the impacts of three sorting techniques on various cognitive tasks performed on a tabular representation. The tasks under study were a multiattribute object selection task and selected low-level analytic tasks. Three sorting techniques, including sorting by a column (Typical Sort), sorting by all columns simultaneously (SimulSort), and sorting by all columns with faithful vertical locations (ParallelTable), were compared with a static table without the sorting feature (Baseline). An incentivized controlled laboratory study with 80 participants and a preliminary eye-tracker study were conducted to better understand the strengths and weaknesses of the four different approaches. SimulSort and ParallelTable were found to significantly improve the performance of multiattribute object selection. ParallelTable, however, suffers from an occlusion problem, so it is not an appropriate support for some low-level analytic tasks. The findings were used to propose appropriate sorting techniques for specific tasks performed on a table.  相似文献   
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A study was carried out to characterize the microstructure and distribution of some mechanical properties in reinforced reaction injection molding panels (RRIM). The panels were prepared under a variety of processing conditions. Scanning electron microscopy, differential scanning calorimetry, and Fourier transform infrared analysis were employed for microstructure characterization. The following mechanical tests were carried out: dynamic mechanical, tensile, and impact. The results indicate significant relationships between processing conditions, microstructure, and mechanical properties. In particular, the skin/core structure of the panels and the size distribution of bubbles in the matrix have an important effect on the impact properties. Furthermore, the balance between the distributions of cure and crystallinity, which is difficult to define clearly, plays an important role in determining panel behavior.  相似文献   
7.
Scientific workflow systems support various workflow representations, operational modes, and configurations. Regardless of the system used, end users have common needs: to track the status of their workflows in real time, be notified of execution anomalies and failures automatically, perform troubleshooting, and automate the analysis of the workflow results. In this paper, we describe how the Stampede monitoring infrastructure was integrated with the Pegasus Workflow Management System and the Triana Workflow Systems, in order to add generic real time monitoring and troubleshooting capabilities across both systems. Stampede is an infrastructure that provides interoperable monitoring using a three-layer model: (1) a common data model to describe workflow and job executions; (2) high-performance tools to load workflow logs conforming to the data model into a data store; and (3) a common query interface. This paper describes the integration of Stampede monitoring architecture with Pegasus and Triana and shows the new analysis capabilities that Stampede provides to these workflow systems. The successful integration of Stampede with these workflow engines demonstrates the generic nature of the Stampede monitoring infrastructure and its potential to provide a common platform for monitoring across scientific workflow engines.  相似文献   
8.
The objective of this study was to compare the efficiency of hormonal treatments on ovarian activity and reproductive performance in anestrous Anglo-Nubian does during the nonbreeding season (February to May). A total of 48 multiparous does were divided into 2 groups (24 lactating does and 24 dry does). In each group, animals were allocated randomly into 2 equal subgroups (12 does each). In the first subgroup, does received a single 18-mg melatonin implant for 42 d followed by a controlled internal drug release (CIDR) device for 19 d in conjunction with 500 IU of equine chorionic gonadotropin (eCG) i.m. on the day of CIDR device removal. The second subgroup received CIDR combined with eCG in parallel with the first subgroup. Melatonin implantation induced a luteotrophic effect, expressed as an increasing number of corpora lutea, increased serum progesterone concentration, and reduced estradiol concentration. Regardless of treatment, dry does showed greater value of progesterone concentration. With the advancement of day of treatment, number of total follicles, small follicles, and medium follicles tended to increase to the greatest values at the day of CIDR device insertion. Furthermore, at day of mating, the numbers of large follicles reached the greatest value, which was associated with the lowest value of the number of corpora lutea. At day of mating, serum progesterone concentration achieved the lowest value, which increased until d 56 of pregnancy. The estradiol:progesterone ratio showed the opposite trend. The detrimental effect of reproductive seasonality, expressed as cessation of estrus behavior and fertile mating during the nonbreeding season, was successfully alleviated by the CIDR-eCG protocol. Furthermore, melatonin implantation in conjunction with the CIDR-eCG protocol enhanced conception rate and fecundity at d 28 of pregnancy and prolificacy at d 56 of pregnancy compared with does that were not implanted. Interestingly, does that failed to conceive did not come to heat again. In conclusion, the beneficial effect of melatonin implantation in conjunction with the CIDR-eCG protocol on the luteotrophic effect was reflected in the increasing number of corpora lutea, increasing progesterone concentration, and decreasing estradiol concentration. Furthermore, conception rate, prolificacy, and fecundity were improved compared with does that were not implanted during the nonbreeding season.  相似文献   
9.
Wagatea spicata, candy corn plant, a woody legume shrub, widespread medicinal plant found in Western Ghat of India has significant abilities to scavenge highly reactive free radicals. Shade dried leaf, bark and flower powder of this plant has been extracted with water and fractionated with different solvents. Extracts and their solvent fractions were found to be good scavengers of superoxide and hydroxyl radicals. Free radical scavenging action of W. spicata is due to its rich phenolic and flavonoid contents. Bark and leaf extracts showed significant scavenging action against superoxide radicals, where as flower extracts efficiently inhibited hydroxyl radicals.  相似文献   
10.
UV-B irradiation was applied to broccoli florets to investigate its effect on chlorophyll degradation and chlorophyll-degrading enzyme activities in stored broccoli. Broccoli florets were irradiated with UV-B doses at 4.4, 8.8, and 13.1 kJ m−2 and then kept at 15 °C in darkness. We found that a UV-B dose of at least 8.8 kJ m−2 efficiently delayed the decrease of the hue angle value and the contents of chlorophylls a and b. Chlorophyllide a and 132-hydroxychlorohyll a gradually decreased with senescence. Pheophorbide a and pyropheophorbide a levels were significantly higher in broccoli without UV-B treatment. Chlorophyllase and chlorophyll-degrading peroxidase activities with UV-B treatment were suppressed, as well as the activity of Mg-dechelatase. Mg-dechelating substance activity was also suppressed with this treatment. We concluded that UV-B treatment effectively suppressed chlorophyll degradation in broccoli florets during storage, suggesting that the effect could be due to the suppression of chlorophyll-degrading enzyme activities.  相似文献   
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