全文获取类型
收费全文 | 114篇 |
免费 | 9篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 40篇 |
金属工艺 | 2篇 |
能源动力 | 1篇 |
轻工业 | 1篇 |
无线电 | 8篇 |
一般工业技术 | 32篇 |
冶金工业 | 13篇 |
自动化技术 | 25篇 |
出版年
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 1篇 |
2020年 | 5篇 |
2019年 | 6篇 |
2018年 | 7篇 |
2017年 | 1篇 |
2016年 | 6篇 |
2015年 | 3篇 |
2014年 | 4篇 |
2013年 | 10篇 |
2012年 | 2篇 |
2011年 | 5篇 |
2010年 | 5篇 |
2009年 | 8篇 |
2008年 | 7篇 |
2007年 | 6篇 |
2006年 | 3篇 |
2003年 | 2篇 |
2002年 | 1篇 |
2000年 | 6篇 |
1999年 | 1篇 |
1998年 | 7篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1984年 | 1篇 |
1979年 | 1篇 |
1976年 | 3篇 |
1975年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有123条查询结果,搜索用时 31 毫秒
1.
Georg Menge Hannes Lorenz Zongwen Fu Franziska Eichhorn Florian Schader Kyle G. Webber Tobias Fey Peter Greil Nahum Travitzky 《Advanced Engineering Materials》2018,20(7)
2.
We introduce the concert (or cafeteria) queueing problem: A finite but large number of customers arrive into a queueing system
that starts service at a specified opening time. Each customer is free to choose her arrival time (before or after opening
time), and is interested in early service completion with minimal wait. These goals are captured by a cost function which
is additive and linear in the waiting time and service completion time, with coefficients that may be class dependent. We
consider a fluid model of this system, which is motivated as the fluid-scale limit of the stochastic system. In the fluid
setting, we explicitly identify the unique Nash-equilibrium arrival profile for each class of customers. Our structural results
imply that, in equilibrium, the arrival rate is increasing up until the closing time where all customers are served. Furthermore,
the waiting queue is maximal at the opening time, and monotonically decreases thereafter. In the simple single class setting,
we show that the price of anarchy (PoA, the efficiency loss relative to the socially optimal solution) is exactly two, while
in the multi-class setting we develop tight upper and lower bounds on the PoA. In addition, we consider several mechanisms
that may be used to reduce the PoA. The proposed model may explain queueing phenomena in diverse settings that involve a pre-assigned
opening time. 相似文献
3.
Zaritsky Reuven Peterfreund Natan Shimkin Nahum 《International Journal of Computer Vision》2003,51(3):219-238
This paper presents a 3D active contour model for boundary detection and tracking of non-rigid objects, which applies stereo vision and motion analysis to the class of energy-minimizing deformable contour models, known as snakes. The proposed contour evolves in three-dimensional space in reaction to a 3D potential function, which is derived by projecting the contour onto the 2D stereo images. The potential function is augmented by a kinetic term, which is related to the velocity field along the contour. This term is used to guide the inter-image contour displacement. The incorporation of inter-frame velocity estimates in the tracking algorithm is especially important for contours which evolve in 3D space, where the added freedom of motion can easily result in loss of tracking. The proposed scheme incorporates local velocity information seamlessly in the snake model, with little computational overhead, and does not require exogenous computation of the optical flow or related quantities in each image. The resulting algorithm is shown to provide good tracking performance with only one iteration per frame, which provides a considerable advantage for real time operation. 相似文献
4.
Steferson Luiz Stares Alina Kirilenko Márcio Celso Fredel Peter Greil Lothar Wondraczek Nahum Travitzky 《Advanced Engineering Materials》2013,15(4):230-237
Porous bioactive glass (BaG) structures were manufactured applying novel preceramic paper process. Preceramic papers were produced for aqueous suspensions loaded with different contents of pulp fiber and BaG filler. Pressure loading was applied in order to increase the packing density in the paper sheets. The paper sheets were sintered at 630 °C for 1 h. The porous glass–ceramic specimens were characterized for density, porosity, composition, microstructure, and mechanical properties. A pronounced volumetric shrinkage was observed, but no surface flaws or inhomogeneous areas were detected. The mechanical strength using the ball on three balls test and elastic modulus of sintered specimens vary between 21 and 33 MPa and 0.30–0.85 GPa, respectively. 相似文献
5.
Yeon-Suk Jang Michael Jank Verena Maier Karsten Durst Nahum Travitzky Cordt Zollfrank 《Journal of the European Ceramic Society》2010,30(13):2773-2779
Micropatterned SiC ceramics were fabricated from polycarbosilanes applying a softlithographic replication technique. A polydimethylsiloxane mould replicated from a photolithographic microstructured silicon wafer was used as master structure. The polydimethylsiloxane mould was coated with a solution containing a mixture of two different polycarbosilanes in n-octane. After treatment at 200–400 °C the cross-linked polycarbosilane films were debonded and pyrolysed at 900 °C in nitrogen and subsequently crystallised at temperatures up to 1500 °C in argon. The cross-linking and thermal degradation behaviour of the polycarbosilanes was investigated by Fourier-transform infrared spectroscopy, differential scanning calorimetry and thermogravimetric analysis. X-ray diffractrometry showed the expected development of a nanocrystalline β-SiC (3 nm) as the main phase with increasing temperature. However, traces of α-SiO2 derived from the polycarbosilane precursors were also detected by X-ray analysis. Removal of the α-SiO2 dioxide with hydrofluoric acid in the pyrolysed samples and subsequent increased the crystallite size to 7 nm. The Young's modulus determined by nanoindentation was increased from 3 GPa after cross-linking to 110 GPa after crystallisation. Scanning electron microscopy revealed, that the initial micropatterns were fully retained in the pyrolysed and crystallised SiC ceramics. The micropatterned cross-linked and crystallised β-SiC based substrates exhibited light scattering characteristics, which qualify them as promising candidates for diffractive optical elements in microoptical applications. 相似文献
6.
7.
Adjunctive ventilatory strategies have been developed to improve oxygenation and carbon dioxide (CO2) removal during mechanical ventilation of critically ill patients. These techniques allow clinicians to attain their clinical goals at lower levels of ventilatory support. In this article, the authors discuss extracorporeal CO2 removal, venovenous intravena caval oxygenator, and tracheal gas insufflation as adjuncts to CO2 removal and nitric oxide, surfactant replacement therapy, perfluorocarbon-associated gas exchange, and prone positioning as adjuncts to oxygenation. 相似文献
8.
Liberato Ferrara Alessio Caverzan Lior Nahum Alva Peled 《Materials and Structures》2016,49(5):1747-1760
In this work a granular cementitious composite has been developed, tailoring its performance to a low compressive strength and high deformation and energy dissipation capacity, which can be required to the material when employed in post-installed screeds for protection of structures and infrastructures against accidental actions such as impact and blast. The required level of performance can be achieved by uniform grain size distribution, paste content as low as minimum theoretical void ratio and low paste strength: it is believed that the synergy between the aforementioned three requirements can allow for energy dissipation capacity after paste cracking due to both rearrangement of grain meso-structure and, in case, grain crushing. After the mix design concept and optimization of the material composition, illustrated in the first part of this companion paper study, the mechanical performance of the composite under static and impact compressive loadings has been thoroughly characterized, as affected by mix-design variables, such as paste volume fraction, water to cement ratio and aggregate size. The reliability will thus be thoroughly checked, of the employed material concept, and the influence will also be investigated, if any, of specimen shape, size and boundary conditions. 相似文献
9.
Cynthia M. Gomes Carlos R. Rambo Antonio Pedro Novaes de Oliveira Dachamir Hotza Douglas Gouvêa Nahum Travitzky Peter Greil 《Journal of the American Ceramic Society》2009,92(6):1186-1191
Green tapes of Li2 O–ZrO2 –SiO2 –Al2 O3 (LZSA) parent glass were produced by aqueous tape casting as the starting material for the laminated object manufacturing (LOM) process. The rheological behavior of the powder suspensions in aqueous media, as well as the mechanical properties of the cast tapes, was evaluated. According to ξ potential measurements, the LZSA glass powder particles showed acid surface characteristics and an IEP of around 4 when in aqueous media. The critical volume fraction of solids was about 72 wt% (27 vol%), which hindered the processability of more concentrated slurries. The glass particles also showed an anisometric profile, which contributed to an increase in the interactions between particles during flow. Therefore, the suspensions could not be processed at high solids loadings. Aqueous-based glass suspensions were also characterized by shear thickening after the addition of dispersants. Three slurry compositions were formulated, suitable green tapes were cast, and tapes were successfully laminated by LOM to a gear wheel geometry. A higher tensile strength of the green tapes corresponded to a higher tensile strength of the laminates. Thermal treatment was then applied to the laminates: pyrolysis at 525°C, sintering at 700°C for 1 h, and crystallization at 850°C for 30 min. A 20% volumetric shrinkage was observed, but no surface flaws or inhomogeneous areas were detected. The sintered part maintained the curved edges and internal profile after heat treatment. 相似文献
10.
International Journal of Computer Vision - 相似文献