全文获取类型
收费全文 | 280篇 |
免费 | 7篇 |
专业分类
电工技术 | 5篇 |
综合类 | 2篇 |
化学工业 | 71篇 |
机械仪表 | 1篇 |
建筑科学 | 10篇 |
能源动力 | 9篇 |
轻工业 | 42篇 |
水利工程 | 4篇 |
无线电 | 15篇 |
一般工业技术 | 27篇 |
冶金工业 | 70篇 |
自动化技术 | 31篇 |
出版年
2022年 | 9篇 |
2021年 | 11篇 |
2020年 | 6篇 |
2019年 | 3篇 |
2018年 | 3篇 |
2017年 | 7篇 |
2016年 | 3篇 |
2014年 | 11篇 |
2013年 | 11篇 |
2012年 | 11篇 |
2011年 | 9篇 |
2010年 | 10篇 |
2009年 | 9篇 |
2008年 | 7篇 |
2007年 | 7篇 |
2006年 | 4篇 |
2005年 | 5篇 |
2004年 | 6篇 |
2003年 | 8篇 |
2002年 | 6篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 3篇 |
1996年 | 3篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 4篇 |
1992年 | 4篇 |
1991年 | 5篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1986年 | 6篇 |
1985年 | 5篇 |
1984年 | 8篇 |
1983年 | 4篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1976年 | 7篇 |
1975年 | 3篇 |
1973年 | 3篇 |
1970年 | 6篇 |
1969年 | 3篇 |
1967年 | 5篇 |
1966年 | 3篇 |
1928年 | 2篇 |
1926年 | 2篇 |
1923年 | 3篇 |
1912年 | 2篇 |
排序方式: 共有287条查询结果,搜索用时 0 毫秒
1.
2.
Poly(diaryl diazosulfide)s and model diaryl diazosulfides of the general structure aryl-N?N? S-aryl' are tested for their thermostability. Thermolysis in solution is followed by means of UV spectroscopy. At the beginning of the decay most model diazosulfides follow first-order kinetics, but show an acceleration of the decay rate in the further course of the thermolysis. In contrast to the models the decomposition of the corresponding polymers cannot be described by first-order kinetics, except one example ( P 1 ). Thermogravimetry studies show weight losses of 8–12% in the range between 80 and 150°C depending on the structure of the models and polymeric diazosulfides. These values correspond with the content of azo function in these compounds, therefore it is assumed that nitrogen is split off under these reaction conditions. 相似文献
3.
Oskar Elek Pablo Bauszat Tobias Ritschel Marcus Magnor Hans‐Peter Seidel 《Computer Graphics Forum》2014,33(4):113-122
Light refracted by a dispersive interface leads to beautifully colored patterns that can be rendered faithfully with spectral Monte‐Carlo methods. Regrettably, results often suffer from chromatic noise or banding, requiring high sampling rates and large amounts of memory compared to renderers operating in some trichromatic color space. Addressing this issue, we introduce spectral ray differentials, which describe the change of light direction with respect to changes in the spectrum. In analogy with the classic ray and photon differentials, this information can be used for filtering in the spectral domain. Effectiveness of our approach is demonstrated by filtering for offline spectral light and path tracing as well as for an interactive GPU photon mapper based on splatting. Our results show considerably less chromatic noise and spatial aliasing while retaining good visual similarity to reference solutions with negligible overhead in the order of milliseconds. 相似文献
4.
The advent of modern mobile phones, 3G networks, and live video streaming has made it possible to broadcast live video from mobile devices. This is now giving rise to a new class of applications which enable mobile collaborative live video production, in which groups of amateurs work together to provide a rich broadcast of events. We focus on new and expected synchronization problems that arise in these more complex systems when broadcasting live events because of the delays that often occur in streaming over internet and mobile networks. The problem has been investigated by acquiring initial user feedback, as well as conducting technical delay measurements of two examples of such systems and relating them to existing literature. We identified two types of technical problems which affect the mixing of the streams, namely the difference in delay in multiple streams, a.k.a. asynchrony among streams, and the delay between the event itself and its presentation in the mixer. These problems affect the mixing in various ways depending on whether or not the director has visual access to the unmediated event. This knowledge has then been used to inform the conceptualization of identifiable ways of handling delays and synchronization. We suggest the introduction of a software feature providing context-dependent delay, in which these requirements can be balanced differently to fit specific contexts of use. We specifically address the different types of mixing which occurs when the director, or mixer, only has access to the topic through the mobile media (“out of view”), as well as mixing in a context in which the topic also is physically present (“in-view”) in front of the mixer. 相似文献
5.
William G. Booty Isaac Wong David Lam Oskar Resler 《Environmental Modelling & Software》2009,24(8):889-900
The Environmental Effects Monitoring (EEM) Statistical Assessment Tool (SAT) Decision Support System (DSS) has been developed to provide a user-friendly data analysis, display and decision support tool for Canada's federal environmental effects monitoring program for the pulp and paper and mining industries. The target users include industries, consultants, regional EEM coordinators, National EEM Office and scientists involved in EEM-related research. The tool allows the assessment of the effects of effluent from industrial or other sources on fish and benthic populations. Effect endpoints, which are used as indicators of potentially important effluent effects, are measured at effluent-exposed sites and are compared statistically to measures at reference sites, in order to determine if changes have occurred and the magnitude of the changes. The main driver of the EEM-SAT DSS is its rule-based expert system. The results are used in assessing the adequacy of existing regulations for protecting aquatic environments. 相似文献
6.
Yong Ryun Kim Oskar J. Sandberg Stefan Zeiske Gregory Burwell Drew B. Riley Paul Meredith Ardalan Armin 《Advanced functional materials》2023,33(16):2300147
Poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) has been one of the most established hole transport layers (HTL) in organic solar cells (OSCs) for several decades. However, the presence of PSS− ions is known to deteriorate device performance via a number of mechanisms including diffusion to the HTL-active layer interface and unwanted local chemical reactions. In this study, it is shown that PSS− ions can also result in local p-doping in the high efficiency donor:non-fullerene acceptor blends – resulting in photocurrent loss. To address these issues, a facile and effective approach is reported to improve the OSC performance through a two-component hole transport layer (HTL) consisting of a self-assembled monolayer of 2PACz ([2-(9H-Carbazol-9-yl)ethyl]phosphonic acid) and PEDOT:PSS. The power conversion efficiency (PCE) of 17.1% using devices with PEDOT:PSS HTL improved to 17.7% when the PEDOT:PSS/2PACz two-component HTL is used. The improved performance is attributed to the overlaid 2PACz layer preventing the formation of an intermixed p-doped PSS− ion rich region (≈5–10 nm) at the bulk heterojunction-HTL contact interface, resulting in decreased recombination losses and improved stability. Moreover, the 2PACz monolayer is also found to reduce electrical shunts that ultimately yield improved performance in large area devices with PCE enhanced from 12.3% to 13.3% in 1 cm2 cells. 相似文献
7.
Oskar Maier Halina Kwasnicka Michal Stanek 《Journal of Intelligent Information Systems》2012,39(3):651-685
Developing a satisfactory and effective method for auto-annotating images that works under general conditions is a challenging task. The advantages of such a system would be manifold: it can be used to annotate existing, large databases of images, rendering them accessible to text search engines; or it can be used as core for image retrieval based on a query image’s visual content. Manual annotation of images is a difficult, tedious and time consuming task. Furthermore, manual annotations tend to show great inter-person variance: considering an image, the opinions about what elements are significant and deserve an annotation vary strongly. The latter poses a problem for the evaluation of an automatic method, as an annotation’s correctness is greatly subjective. In this paper we present an automatic method for annotating images, which addresses one of the existing methods’ major limitation, namely a fixed annotation length. The proposed method, PATSI, automatically chooses the resulting annotation’s length for each query image. It is held as simple as possible and a build-in parameter optimization procedure renders PATSI de-facto parameter free. Finally, PATSI is evaluated on standard datasets, outperforming various state-of-the-art methods. 相似文献
8.
Urushihara Kouji; Wheeler Daniel S.; Pine?o Oskar; Miller Ralph R. 《Canadian Metallurgical Quarterly》2005,31(2):184
Three conditioned taste aversion experiments with rats investigated superconditioning. In each experiment, alternate exposures of 2 flavor compounds with a common element (i.e., AB/AS) were administered to establish an inhibitory relationship between the 2 unique elements, B and S, and prior to testing, S was paired with lithium chloride (LiCl). In Experiment 1, pairings of a neutral cue (X) with S in compound with B after the AB/AS exposures resulted in superconditioning between X and S. Extinction of the common element (A) just before the S-LiCl pairing attenuated both the inhibitory relationship between B and S (Experiment 2) and superconditioning between X and S (Experiment 3). These observations suggest that superconditioning consists of enhanced performance rather than enhanced associative acquisition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
HUGOOskar ZLATOGORMinchev 《哈尔滨理工大学学报》2003,8(1):15-19
传输信息常涉及到不同的难题。当保护信息免受非控制访问时,一个新的似然性可能得以应用,即无序。由于在安全通信中实施无序的兴趣日见增加,已经提出许多设计方案。本文提出了建立非线性动态无序系统模型的方法,并进行了通用网的设计与访真。 相似文献
10.
Magnetic tracking is a popular technique that exploits static and low-frequency magnetic fields for positioning of quasi-stationary objects. One important system design aspect, which substantially influences the performance of the tracking system, is how to collect as much information as possible with a given number of measurements. In this work, we optimize the allocation of measurements given a large number of possible measurements of a generic magnetic tracking system that exploits time-division multiplexing. We exploit performance metrics based on the Fisher information matrix. In particular, the performance metrics measure worst-case or average performance in a measurement domain, i.e. the domain where the tracking is to be performed. An optimization problem with integer variables is formulated. By relaxing the constraint that the variables should be integer, a convex optimization problem is obtained. The two performance metrics are compared for several realistic measurement scenarios with planar transmitter constellations. The results show that the worst performance is obtained in the most distant parts of the measurement domain. Furthermore, measurement allocations optimized for worst-case performance require measurements in a larger area than measurement allocations optimized for average performance. 相似文献