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71.
The paper proposes a methodology to assist the designer at the initial stages of the design synthesis process by enabling him/her to employ knowledge and algorithms existing in graph network theory. The proposed method comprises three main stages: transforming the synthesis problem into a graph theoretic problem; devising the topology possessing special engineering properties corresponding to the system requirements; finding the geometric configuration of that topology that will possess the desired properties. To clarify the idea and to demonstrate its generality, the approach is presented through three synthesis case studies from different engineering domains: electrical networks, statics and kinematics.As is highlighted in the paper, the approach of employing graph theory in the synthesis process offers several unique advantages. Among these advantages are: gaining a general perspective on different synthesis problems from different engineering domains by transforming them into the same graph problem; employing the same graph algorithms for different synthesis problems; establishing the existence of configurations with special properties solely from the topology of the system; transferring knowledge and methods between different engineering disciplines for both the topology and the geometry generation steps. 相似文献
72.
Neta Zilony‐Hanin Michal Rosenberg Michal Richman Ronen Yehuda Hadas Schori Menachem Motiei Shai Rahimipour Alexander Groisman Ester Segal Orit Shefi 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(45)
Nerve growth factor (NGF) plays a vital role in reducing the loss of cholinergic neurons in Alzheimer's disease (AD). However, its delivery to the brain remains a challenge. Herein, NGF is loaded into degradable oxidized porous silicon (PSiO2) carriers, which are designed to carry and continuously release the protein over a 1 month period. The released NGF exhibits a substantial neuroprotective effect in differentiated rat pheochromocytoma PC12 cells against amyloid‐beta (Aβ)‐induced cytotoxicity, which is associated with Alzheimer's disease. Next, two potential localized administration routes of the porous carriers into murine brain are investigated: implantation of PSiO2 chips above the dura mater, and biolistic bombardment of PSiO2 microparticles through an opening in the skull using a pneumatic gene gun. The PSiO2‐implanted mice are monitored for a period of 8 weeks and no inflammation or adverse effects are observed. Subsequently, a successful biolistic delivery of these highly porous microparticles into a live‐mouse brain is demonstrated for the first time. The bombarded microparticles are observed to penetrate the brain and reach a depth of 150 µm. These results pave the way for using degradable PSiO2 carriers as potential localized delivery systems for NGF to the brain. 相似文献
73.
A single center,open‐label,randomized, parallel group study assessing the relationship between asymptomatic bacteriuria and inflammation in maintenance hemodialysis patients 下载免费PDF全文
Ilia Beberashvili Evgeni Golovko Liat Golinsky Nedal Garra Inna Sinuani Leonid Feldman Oleg Gorelik Shai Efrati Kobi Stav 《Hemodialysis international. International Symposium on Home Hemodialysis》2018,22(1):110-118
Introduction: The significance of asymptomatic bacteriuria in maintenance hemodialysis (MHD) patients remains controversial. We hypothesized that the presence of asymptomatic bacteriuria as a sole clinical manifestation of urinary tract infection (UTI) in asymptomatic MHD patient may contribute to the chronic inflammatory response. Our aim was to explore the relationship between asymptomatic bacteriuria and elevated levels of inflammatory markers in MHD patients. Methods: A randomized open‐label single center study of 114 MHD patients was conducted. Forty‐six patients presented negative urine culture and 41 subjects were excluded due to different reasons. The remaining 27 patients (mean age of 71.5 ± 12.2 years, 63% men), fulfilling the criteria for having asymptomatic bacteriuria, were randomly assigned to either the treatment group (13 patients) or the observational group (14 subjects). The treatment group received 7 days of antibiotic treatment given according to bacteriogram sensitivity. After 3 months of follow‐up all measurements of the study were repeated. The primary end point was change in inflammatory biomarkers from baseline by the end of the study. Findings: There were no statistically significant differences in white blood cell changes (P = 0.27), ferritin (P = 0.09), C‐reactive protein (P = 0.90), and interleukin‐6 (P = 0.14) levels between the groups from baseline to the end of study or at the end of the study. Analyzing cross‐sectional data, asymptomatic bacteriuria was found to not be a predictor of higher levels of inflammatory parameters at baseline. Discussion: Asymptomatic bacteriuria is not a modifiable risk factor for chronic inflammation in the MHD population. 相似文献
74.
A field study of 50 households in a collective community in Israel provides initial support for the hypotheses about the relations between actors’ agency, capacity and electricity demand reduction. ‘Agency’ refers to actors’ willingness and ability to make their own free choices and ‘capacity’ refers to actors’ ability to perform the choices they made. According to the hypotheses, change is more likely to happen when actors’ levels of agency and capacity are high; unlikely to happen when the levels are low and uncertain when there is a mismatch between levels of agency and capacity (one is high and the other low). In the research, levels of agency and capacity regarding 11 energy saving actions were self-reported and electricity consumption was metered before and during energy saving campaign. Findings show that levels of agency were lower than those of capacity for no-cost actions which require high engagement, while levels of capacity were lower than those of agency for high-cost action which require low engagement. In addition, households with high agency and high capacity reduced their electricity consumption by 9.39 % (on average); those with low agency and low capacity increased their consumption by 6.67 %; and those with a mismatch between agency and capacity reduced their consumption by 1.91 %. 相似文献
75.
Pati Soumen Kumar Gupta Manan Kumar Shai Rinita Banerjee Ayan Ghosh Arijit 《Knowledge and Information Systems》2022,64(10):2661-2687
Knowledge and Information Systems - Microarray data analysis needs utmost care as it plays a significant role in cancer study. Due to the excessive complexity of the data extraction process, it... 相似文献
76.
In a Simon task the effects of spatial cues and attention on spatial stimulus coding were explored. Participants made speeded responses corresponding to the direction of target arrows that were preceded by peripherally presented cues. Cue validity varied across experiments as did the percentage of trials on which the target appeared peripherally or centrally. The data indicate (a) that targets are coded relative to multiple reference frames, (b) that spatial coding of a target is not affected when attention is shifted to the target, and (c) that an object serves as a referent for spatial coding of other objects even after its spatial code no longer activates responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
There is substantial literature dealing with fixed parameter algorithms for the dominating set problem on various families
of graphs. In this paper, we give a k
O(dk)
n time algorithm for finding a dominating set of size at most k in a d-degenerated graph with n vertices. This proves that the dominating set problem is fixed-parameter tractable for degenerated graphs. For graphs that
do not contain K
h
as a topological minor, we give an improved algorithm for the problem with running time (O(h))
hk
n. For graphs which are K
h
-minor-free, the running time is further reduced to (O(log h))
hk/2
n. Fixed-parameter tractable algorithms that are linear in the number of vertices of the graph were previously known only for
planar graphs.
For the families of graphs discussed above, the problem of finding an induced cycle of a given length is also addressed. For
every fixed H and k, we show that if an H-minor-free graph G with n vertices contains an induced cycle of size k, then such a cycle can be found in O(n) expected time as well as in O(nlog n) worst-case time. Some results are stated concerning the (im)possibility of establishing linear time algorithms for the more
general family of degenerated graphs.
A preliminary version of this paper appeared in the Proceedings of the 13th Annual International Computing and Combinatorics
Conference (COCOON), Banff, Alberta, Canada (2007), pp. 394–405.
N. Alon research supported in part by a grant from the Israel Science Foundation, and by the Hermann Minkowski Minerva Center
for Geometry at Tel Aviv University.
This paper forms part of a Ph.D. thesis written by S. Gutner under the supervision of Prof. N. Alon and Prof. Y. Azar in Tel
Aviv University. 相似文献
78.
A. K. Aleshin V. A. Glazunov G. V. Rashoyan Offer Shai 《Journal of Machinery Manufacture and Reliability》2016,45(4):291-296
The kinematic screws that determine the topology of singular zones of parallel-structure robots are studied. It has been established that the kinematic screws depend on the actuator mount points. 相似文献
79.
Shai Salhov Michael Aizenshtein Natalie Froumin Shmuel Barzilai Nahum Frage 《Journal of Materials Science》2013,48(8):3173-3176
The interaction between NaCl–KCl salt of an equimolar composition and CaF2 was investigated in the 1023–1123 K temperature range. The solubility limit was determined as 2.1, 2.5, and 3.4 mol.% for 1023, 1073, and 1123 K, respectively. The linear dependence of the specific weight loss with time and the activation energy of the dissolution (124.6 ± 8.7 kJ/mol) indicate that CaF2 dissociation of the ions is the limiting stage of the process. Thermodynamic properties (partial enthalpy and entropy) of CaF2 in a dilute ternary –NaCl–KCl–CaF2 liquid solution were estimated using the values of the solubility limit and by applying a regular solution approach. 相似文献
80.
A numerical computer code was developed for calculating the combined conduction and radiation transient heat transfer in cylindrical, semitransparent materials that have temperature-dependent thermal properties. The radiative component is combined with the equation of conduction heat transfer by adding it as a heat source. The finite element method (FEM) was used for calculating the radiative component and for solving the temperature field in the medium. Very good agreement was observed between results obtained by using our code and those that exist in the literature for several steady-state cases. The advantage of the code is due to the fact that it incorporates temperature-dependent properties; thus it leads to more realistic and accurate results. The code was applied to calculate the cooling path of a large cylindrical sapphire boule while using varying, transient, temperature-dependent, combined heat transfer coefficients. 相似文献