全文获取类型
收费全文 | 210篇 |
免费 | 17篇 |
专业分类
电工技术 | 4篇 |
综合类 | 1篇 |
化学工业 | 56篇 |
机械仪表 | 3篇 |
建筑科学 | 13篇 |
能源动力 | 30篇 |
轻工业 | 40篇 |
无线电 | 12篇 |
一般工业技术 | 28篇 |
冶金工业 | 11篇 |
原子能技术 | 2篇 |
自动化技术 | 27篇 |
出版年
2024年 | 2篇 |
2023年 | 5篇 |
2022年 | 10篇 |
2021年 | 15篇 |
2020年 | 9篇 |
2019年 | 9篇 |
2018年 | 7篇 |
2017年 | 10篇 |
2016年 | 7篇 |
2015年 | 15篇 |
2014年 | 9篇 |
2013年 | 29篇 |
2012年 | 8篇 |
2011年 | 21篇 |
2010年 | 17篇 |
2009年 | 12篇 |
2008年 | 6篇 |
2007年 | 12篇 |
2006年 | 7篇 |
2005年 | 2篇 |
2004年 | 1篇 |
2003年 | 6篇 |
2002年 | 1篇 |
2001年 | 2篇 |
1996年 | 1篇 |
1993年 | 1篇 |
1990年 | 2篇 |
1984年 | 1篇 |
排序方式: 共有227条查询结果,搜索用时 15 毫秒
91.
92.
Koç Mehmet Güngör Özlühan Zungur Aslı Yalçın Buket Selek İlknur Ertekin Figen Kaymak Ötles Semih 《Food and Bioprocess Technology》2015,8(2):301-318
Food and Bioprocess Technology - The objective of the study was to investigate the microencapsulation of extra virgin olive oil by spray drying to increase its stability and application area. The... 相似文献
93.
94.
95.
Yalçın U 《Applied optics》2011,50(3):296-302
Uniform diffracted fields from impedance surfaces are investigated by the extended theory of boundary diffraction wave (ETBDW). The new vector potential of the ETBDW is constructed by considering the pseudoimpedance boundary condition. The method is applied to the diffraction problem from an impedance half-plane. It is shown that the total fields from an impedance half-plane reduce to the case of a perfectly electric or magnetic conducting and opaque half-plane for special values of surface impedance. The total and diffracted fields are compared numerically with the exact solution for the impedance half-plane and modified theory of physical optics (MTPO) solution for an impedance wedge. The numerical results show that the field expressions are in very good agreement with the exact and MTPO solutions. 相似文献
96.
Comparison of new activation functions in neural network for forecasting financial time series 总被引:1,自引:0,他引:1
Gecynalda S. da S. Gomes Teresa B. Ludermir Leyla M. M. R. Lima 《Neural computing & applications》2011,20(3):417-439
In artificial neural networks (ANNs), the activation function most used in practice are the logistic sigmoid function and
the hyperbolic tangent function. The activation functions used in ANNs have been said to play an important role in the convergence
of the learning algorithms. In this paper, we evaluate the use of different activation functions and suggest the use of three
new simple functions, complementary log-log, probit and log-log, as activation functions in order to improve the performance
of neural networks. Financial time series were used to evaluate the performance of ANNs models using these new activation
functions and to compare their performance with some activation functions existing in the literature. This evaluation is performed
through two learning algorithms: conjugate gradient backpropagation with Fletcher–Reeves updates and Levenberg–Marquardt. 相似文献
97.
Castelli Luigi; De Amicis Leyla; Sherman Steven J. 《Canadian Metallurgical Quarterly》2007,43(6):1347
The goal of this article was to investigate an indirect form of intergroup differentiation in children in the context of racial attitudes: the preference for ingroup members who interact positively with other ingroup members rather than with outgroup members. Study 1 confirmed this general hypothesis with preschool and 1st-grade children, demonstrating that respondents preferred the ingroup member who played only with other ingroup members, evaluated this child more positively, and felt more similar to him or her. Studies 2 and 3 tested the boundary conditions of the phenomenon. Study 4 analyzed developmental changes demonstrating that the effect is no longer observed among 9- to 11-year-old children. Overall, these studies suggest that engaging in positive interactions with the outgroup might have its costs in terms of a relative devaluation and rejection by one's peers. Results are discussed by stressing the importance of intragroup processes for the regulation of intergroup relations among very young children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
Jernigan Maryam M.; Green Carlton E.; Helms Janet E.; Perez-Gualdron Leyla; Henze Kevin 《Canadian Metallurgical Quarterly》2010,4(1):62
Considering the growing racial and ethnic diversity among supervisees, the number of clinical supervision dyads comprised of supervisees and supervisors of Color is likely to increase dramatically. Although extant research has focused on supervision that involves White supervisors paired with racial, ethnic, and linguistic minority supervisees, few authors have explored the supervisory dynamics between clinicians of color and supervisees of Color. This study used a qualitative analysis of structured survey responses provided by supervisees of Color to argue that racial identity (i.e., supervisors’ and supervisees’ psychological experiences of race), more than race is essential for managing the racial dynamics of supervisory dyads involving two people of Color. Using Helms Racial Identity Social Interaction Model (Helms, 1990, 1995), we use a directed content analysis of participants’ responses to demonstrate common themes that emerge when race is introduced into the supervision relationship. Based on supervisees’ reported experiences, implications for the practice of supervision involving people of Color are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
With the recent development of information technology and computer network, digital format of data has become more and more popular. However, a major problem faced by digital data providers and owners is protecting data from unauthorized copying and distribution. As a solution to the problem, digital watermark technology is now attracting attention as new method of protection against said unauthorized copying and distribution. The aim of the digital audio watermarking is to take prespecified data that carries certain information and hide it within the audio stream such that it is not audible to the human ear (i.e., transparent) but at the same time renders the file more resistant to removal (i.e., robust). In this paper, we propose a new method for embedding digital watermarks into audio signals in low frequency components, which method mitigates these and other related shortcomings. The proposed method uses the wavelet transform constructed by lifting-based wavelet transform (LBWT) in order to provide a fast implementation between watermark embedding and extraction parts. In the first stage of the proposed method, the original audio host signal is converted to a wavelet domain using LBWT. The signal is thus decomposed into low and high frequency components. Approximation coefficients correspond to low frequency components of the signal. Next, the watermark generated by pseudorandom numbers is embedded into wavelet approximation coefficients of the segmented host audio signal depending on the binary value of the binary image. The reason for embedding the watermark in the low frequency components is that these components' energy is greater than that of high frequency components in such a way that the watermark is inaudible; therefore, it should not alter the audible content and should not be easy to remove. The proposed method uses a binary image to decide whether or not the watermark generated by pseudorandom numbers is embedded in the audio host signal. To evaluate the performance of the proposed audio watermarking method, subjective and objective quality tests including bit error rate (BER) and signal-to-noise ratio (SNR) are conducted. The tests' results show that the proposed method yields a high recovery rate after attacks by commonly used audio data manipulations such as low-pass filtering, requantization, resampling and MP3 compression. 相似文献
100.
This paper presents a robustly stabilizing model predictive control algorithm for systems with incrementally conic uncertain/nonlinear terms and bounded disturbances. The resulting control input consists of feedforward and feedback components. The feedforward control generates a nominal trajectory from online solution of a finite‐horizon constrained optimal control problem for a nominal system model. The feedback control policy is designed off‐line by utilizing a model of the uncertainty/nonlinearity and establishes invariant ‘state tubes’ around the nominal system trajectories. The entire controller is shown to be robustly stabilizing with a region of attraction composed of the initial states for which the finite‐horizon constrained optimal control problem is feasible for the nominal system. Synthesis of the feedback control policy involves solution of linear matrix inequalities. An illustrative numerical example is provided to demonstrate the control design and the resulting closed‐loop system performance. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献