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61.
We demonstrate magnetic switching between two 360° domain wall vortex states in cobalt nanorings, which are candidate magnetic states for robust and low power magnetoresistive random access memory (MRAM) devices. These 360° domain wall (DW) or 'twisted onion' states can have clockwise or counterclockwise circulation, the two states for data storage. Reliable switching between the states is necessary for any realistic device. We accomplish this switching by applying a circular Oersted field created by passing current through a metal atomic force microscope tip placed at the center of the ring. After initializing in an onion state, we rotate the DWs to one side of the ring by passing a current through the center, and can switch between the two twisted states by reversing the current, causing the DWs to split and meet again on the opposite side of the ring. A larger current will annihilate the DWs and create a perfect vortex state in the rings. 相似文献
62.
Jukka Perkiö Antti Tuominen Taneli Vähäkangas Petri Myllymäki 《Multimedia Tools and Applications》2012,57(1):5-27
Measuring image similarity is an important task for various multimedia applications. Similarity can be defined at two levels:
at the syntactic (lower, context-free) level and at the semantic (higher, contextual) level. As long as one deals with the
syntactic level, defining and measuring similarity is a relatively straightforward task, but as soon as one starts dealing
with the semantic similarity, the task becomes very difficult. We examine the use of simple readily available syntactic image
features combined with other multimodal features to derive a similarity measure that captures the weak semantics of an image.
The weak semantics can be seen as an intermediate step between low level image understanding and full semantic image understanding.
We investigate the use of single modalities alone and see how the combination of modalities affect the similarity measures.
We also test the measure on multimedia retrieval task on a tv series data, even though the motivation is in understanding
how different modalities relate to each other. 相似文献
63.
This study deals with managing risks in relationships between a larger final assembler and smaller suppliers. These relationships are often based on asymmetric cooperation where the smaller companies are highly dependent on the larger companies. This dependency can cause significant uncertainty for small and medium-sized enterprises that often operate with a narrow customer structure and minor negotiation power compared with their larger partners. The transaction cost approach (TCA) has been used as a framework for the analysis of uncertainties and risks related with these relationships. Despite the very comprehensive nature of empirical applications and theories of the transaction cost approach, these theories have not been very widely tested in the environment of small and medium-sized enterprises. Our study indicates that dependency and asymmetry are two major uncertainty and transaction cost causing drivers. Closer, long-term relationships are needed in order to minimize the transaction costs and risks. A smaller customer structure increases dependency and reduces partnership-specific transaction costs. The optimal strategy is to balance these opposite drivers. Options and linkages to the company's goals and strategies should therefore be the leading principles in balancing transaction cost uncertainty and risk. Empirical evidence from the electronics industry is presented. Alternative management approaches and further research areas are discussed. 相似文献
64.
Trapping the food safety performance of a small or medium-sized food company using a risk-based model. The HYGRAM system 总被引:1,自引:0,他引:1
Pirkko Tuominen Sebastian Hielm Kaarina Aarnisalo Laura Raaska Riitta Maijala 《Food Control》2003,14(8):573-578
The requirements of implementing Hazard Analysis and Critical Control Points (HACCP) principles in food production are increasing. A practical risk quantification model, HYGRAM, was developed for small and medium-sized enterprises to meet this challenge. The model makes the user familiar with the HACCP principles by software-assisted guidance through the procedure, connecting special microbiological hazards, good hygiene practice, and other prerequisite programs to HACCP. HYGRAM is a tool to analyze and quantify risks of different processes, and to compare them. It is developed to relieve enterprises with limited resources in confirming the food safety of their production. 相似文献
65.
Tuominen A. Jarvi T. Rasanen J. Sirkia A. Himanen V. 《Intelligent Transport Systems, IET》2007,1(2):59-68
The ultimate purpose of the transport system is to serve the needs and expectations of the end users, who in turn shape the system by their own behaviour, actions and investments. This work examines, within the framework of the Large Technological Systems theory the possibility to categorise users of the transport system into homogeneous segments on the basis of their differences in daily mobility and transportation of goods. Furthermore, the potential to deepen this segmentation to describe the needs of, but later in the policy process also the social acceptance by, different user groups for new transport technology or policy, is examined 相似文献
66.
Testing multimodal applications with visually impaired children requires specific testing methods and procedures. In this article, we used a SensAble Phantom device to produce haptic feedback together with stereo sound and visual feedback. We also experimented with low-cost haptic devices, such as force-feedback game controllers and tactile-feedback devices. Here we discuss how to conduct usability testing for multimodal applications with visually impaired children. 相似文献
67.
Intrathecal morphine provides effective postoperative pain relief in major orthopaedic surgery. In use, however, is associated with unpleasant side effects like nausea and vomiting. The effect of different premedications on postoperative emetic sequelae induced by intrathecal morphine was studied in a prospective, double blind study. Sixty patients scheduled for arthroplasty surgery of the lower extremity were anaesthetized with spinal anaesthesia with a combination of isobaric bupivacaine 20 mg and morphine 0.3 mg. For premedication the patients were randomised to three groups of equal size. They received either oral diazepam (5-15 mg), oral promethazine (10 mg) or a combination of promethazine and transdermal scopolamine (1.5 mg). Sixty percent of the patients with both promethazine and transdermal scopolamine were totally free from postoperative nausea and vomiting (PONV) symptoms compared to those premedicated with diazepam (40%) or promethazine alone (30%). Promethazine together with transdermal scopolamine reduced significantly the number of patients with vomiting (to 25%) and also vomiting episodes. This combination was also more efficient in reducing the incidence of nausea (to 25%) and nausea episodes than promethazine along (P < 0.05). Combination also reduced the requests for additional pain relief (P < 0.05). PONV occurred in a majority of patients during the first 12 hours of the 24 hour study period and the need for additional analgesics thereafter. The incidence of itching (50-65%) and urinary catheterisation (55-70%) was similar in all groups. In conclusion, the combination of oral promethazine and transdermal scopolamine was most effective in reducing PONV symptoms and also reduced the need for postoperative pain treatment. 相似文献
68.
Characterization of modified thick thermal barrier coatings 总被引:1,自引:0,他引:1
Ahmaniemi S. Tuominen J. Vippola M. Vuoristo P. Mäntylä T. Cernuschi F. Gualco C. Bonadei A. Di Maggio R. Ahmaniemi S. 《Journal of Thermal Spray Technology》2004,13(3):361-369
In gas turbines and diesel engines, there is a demand for thick thermal barrier coatings (TTBCs) due to the increased process
combustion temperatures. Unfortunately, the increased thickness of plasma-sprayed thermal barrier coatings (TBCs) normally
leads to a reduced coating lifetime. For that reason, the coating structures have to be modified. When modifying the structure
of TTBCs, the focus is normally on elastic modulus reduction of the thick coating to improve the coating strain tolerance.
On the other hand, coating structural modification procedures, such as sealing treatments, can be performed when increased
hot-corrosion resistance or better mechanical properties are needed. In this article, several modified zirconia-based TTBC
structures with specific microstructural properties are discussed. Coating surface sealing procedures such as phosphate sealing,
laser glazing, and sol-gel impregnation were studied as potential methods for increasing the hot-corrosion and erosion resistance
of TTBCs. Some microstructural modifications also were made by introducing segmentation cracks into the coating structures
by laser glazing and by using special spraying parameters. These last two methods were studied to increase the strain tolerance
of TTBCs. The coating microstructures were characterized by optical microscopy, a scanning electron microscopy (SEM), transmission
electron microscopy (TEM), energy dispersive spectroscopy (EDS), and x-ray diffraction (XRD). The effect of sealing procedures
on the basic thermal and mechanical properties of the coatings was studied. In addition, some correlations between the coating
properties and microstructures are also presented, and the advantages and drawbacks of each modification procedure are discussed. 相似文献
69.
Leena Varila Timo Lehtonen Jukka Tuominen Mikko Hupa Leena Hupa 《Journal of materials science. Materials in medicine》2012,23(10):2425-2435
Poly(l,dl-lactide) composites containing filler particles of bioactive glasses 45S5 and S53P4 were compared with a composite containing a slowly dissolving glass S68. The in vitro reactivity of the composites was studied in simulated body fluid, Tris-buffered solution, and phosphate buffered saline. The high processing temperature induced thermal degradation giving cavities in the composites containing 45S5 and S53P4, while good adhesion of S68 to the polymer was observed. The cavities partly affected the in vitro reactivity of the composites. The degradation of the composites containing the bioactive glasses was faster in phosphate buffered saline than in the two other solutions. Hydroxyapatite precipitation suggesting bone tissue bonding capability was observed on these two composites in all three solutions. The slower dissolution of S68 glass particles and the limited hydroxyapatite precipitation suggested that this glass has potential as a reinforcing composition with the capability to guide bone tissue growth in biodegradable polymer composites. 相似文献
70.