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991.
YG Yang JJ Sergio DA Pearson GL Szot A Shimizu M Sykes 《Canadian Metallurgical Quarterly》1997,90(11):4651-4660
We have recently demonstrated that a single injection of 4,900 IU of interleukin-12 (IL-12) on the day of bone marrow transplantation (BMT) markedly inhibits acute graft-versus-host disease (GVHD) in a fully major histocompatibility complex plus minor antigen-mismatched BMT model (A/J --> B10, H-2(a) --> H-2(b)), in which donor CD4(+) T cells are required for the induction of acute GVHD. We show here that donor CD8-dependent graft-versus-leukemia (GVL) effects against EL4 (H-2(b)) leukemia/lymphoma can be preserved while GVHD is inhibited by IL-12 in this model. In mice in which IL-12 mediated a significant protective effect against GVHD, marked GVL effects of allogeneic T cells against EL4 were observed. GVL effects against EL4 depended on CD8-mediated alloreactivity, protection was not observed in recipients of either syngeneic (B10) or CD8-depleted allogeneic spleen cells. Furthermore, we analyzed IL-12-treated recipients of EL4 and A/J spleen cells which survived for more than 100 days. No EL4 cells were detected in these mice by flow cytometry, tissue culture, adoptive transfer, necropsies, or histologic examination. Both GVL effects and the inhibitory effect of IL-12 on GVHD were diminished by neutralizing anti-interferon-gamma (IFN-gamma) monoclonal antibody. This study demonstrates that IL-12-induced IFN-gamma production plays a role in the protective effect of IL-12 against GVHD. Furthermore, IFN-gamma is involved in the GVL effect against EL4 leukemia, demonstrating that protection from CD4-mediated GVHD and CD8-dependent anti-leukemic activity can be provided by a single cytokine, IFN-gamma. These observations may provide the basis for a new approach to inhibiting GVHD while preserving GVL effects of alloreactivity. 相似文献
992.
Batson C. Daniel; Batson Judy G.; Griffitt Cari A.; Barrientos Sergio; Brandt J. Randall; Sprengelmeyer Peter; Bayly Michael J. 《Canadian Metallurgical Quarterly》1989,56(6):922
Tested the suggestion of R. B. Cialdini et al (see record 1987-21901-001) that the motivation to help associated with empathic emotion is directed toward the egoistic goal of negative-state relief, not toward the altruistic goal of relieving the victim's distress. To test this suggestion, we led empathically aroused Ss to anticipate an imminent mood-enhancing experience. We reasoned that if the motivation to help associated with empathy were directed toward the goal of negative-state relief, then empathically aroused individuals who anticipate mood-enhancement should help less than those who do not. Study 1 verified the effectiveness of our anticipated mood-enhancement manipulation; results indicated that this manipulation could serve as an effective source of negative-state relief. Results of Studies 2 and 3, in which empathy was either measured or manipulated, indicated that the rate of helping among high-empathy Ss was no lower when they anticipated mood enhancement than when they did not. Regardless of anticipated mood enhancement, high-empathy Ss helped more than low-empathy Ss. Results support the empathy–altruism hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
On the use of pyrrole black in zinc-halogen batteries 总被引:1,自引:0,他引:1
Giuliano Mengoli Marco M. Musiani Renato Tomat Sergio Valcher Derek Pletcher 《Journal of Applied Electrochemistry》1985,15(5):697-704
The storage of Br2/Br– and I2/I– couples in a conducting polymer matrix, polypyrrole coated on a reticulated vitreous carbon disc, is described and the application of these positive electrodes in zinc-halogen model batteries is discussed. The cell based on the polypyrrole bromine adduct shows the higher open circuit voltage which, however, depends on the state of charge. Such cells self discharge thus limiting their usefulness. In the case of the iodine cell the self discharge is due to loss of iodine from the polymer to the bulk solution, but with the bromine cell the cause is oxidative bromination and depolymerization of the polypyrrole. 相似文献
994.
This research aims to analyse how drivers integrate the information provided by traffic signs with their general goals (i.e. where they want to go). Some previous studies have evaluated the comparative advantages of obligatory and prohibitory traffic signs using a judgement task. In this work, a new experimental task with greater similarity to driving situations is proposed. Participants imagine they are driving a vehicle and must make right or left turn manoeuvres according to a previously indicated objective and the information from obligatory and prohibitory traffic signs. Eighty-two participants took part in two different experiments. According to the results, an obligatory traffic sign is associated with faster and more accurate responses only when the participant's initial objective is allowed. When the initial objective was not allowed, an advantage in accuracy was observed with prohibitory traffic signs and there was no significant difference in reaction time between the two types of sign. These results suggest that having an obligatory traffic sign may facilitate a correct response when the driver's goal is effectively allowed, whereas a prohibitory traffic sign could be more effective in preventing error when the driver has a not-allowed goal in mind. However, processing a prohibitory sign requires an extra inference (i.e. deciding which is the allowed manoeuvre), and thus the potential advantage in reaction time of the prohibitory sign may disappear. A second experiment showed that the results could not be explained by a potential congruency effect between the location (left or right) of the road signs and the position of the key or the hand used to respond (such as the Simon effect or the spatial Stroop effect). Also, an increase in the difficulty of the task (using an incongruent hand to respond) affected performance more strongly in experimental conditions that required making inferences. This made the advantage of the obligatory sign over the prohibitory sign in this condition more noteworthy. The evidence gathered in the current study could be of particular interest in some applied research areas, such as the assessment of road traffic signalling strategies or the ergonomic design of GPS navigation systems. 相似文献
995.
Sergio Cabello 《Algorithmica》2012,62(1-2):361-381
We show how to compute in O(n 4/3log?1/3 n+n 2/3 k 2/3log?n) time the distance between k given pairs of vertices of a planar graph G with n vertices. This improves previous results whenever (n/log?n)5/6≤k≤n 2/log?6 n. As an application, we speed up previous algorithms for computing the dilation of geometric planar graphs. 相似文献
996.
997.
Cardinetti B Ciampini C Abate S Marchetrti C Ferrari F Di Tullio D D'Onofrio C Orlando G Gravina L Torresi L Saporita G 《Scanning》2006,28(3):142-147
The possibility of accidental contamination of a suspect by gunshot residues (GSRs) is considered. If two hypotheses are taken into account ("the suspect has shot a firearm" and "the suspect has not shot a firearm"), the likelihood ratio of the conditional probabilities of finding a number n of GSRs is defined. Choosing two Poisson distributions, the parameter lambda of the first one coincides with the mean number of GSRs that can be found on a firearm shooter, while the parameter mu of the second one is the mean number of GSRs that can be found on a nonshooter. In this scenario, the likelihood ratio of the conditional probabilities of finding a number n of GSRs in the two hypotheses can be easily calculated. The evaluation of the two parameters lambda and mu and of the goodness of the two probability distributions is performed by using different sets of data: "exclusive" lead-antimony-barium GSRs have been detected in two populations of 31 and 28 police officers at diverse fixed times since firearm practice, and in a population of 81 police officers who stated that they had not handled firearms for almost 1 month. The results show that the Poisson distributions well fit the data for both shooters and nonshooters, and that the probability of detection of two or more GSRs is normally greater if the suspect has shot firearms. 相似文献
998.
The condition-based approach studies restrictions on the inputs to a distributed problem, called conditions, that facilitate its solution. Previous work considered mostly the asynchronous model of computation. This paper studies
conditions for consensus in a synchronous system where processes can fail by crashing. It describes a full classification
of conditions for consensus, establishing a continuum between the asynchronous and synchronous models, with the following
hierarchy
where
includes all conditions (and in particular the trivial one made up of all possible input vectors). For a condition
, we have:
After having established the complete hierarchy, the paper concentrates on the two last items:
. The main result is that the necessary and sufficient number of rounds needed to solve uniform consensus for a condition
(such that
) is d +1.
In more detail, the paper presents a generic synchronous early-deciding uniform consensus protocol that enjoys the following
properties. Let f be the number of actual crashes, I the input vector and
the condition the protocol is instantiated with. The protocol terminates in two rounds when
and
, and in at most d +1 rounds when
and
. (It also terminates in one round when
and
.) Moreover, whether I belongs or not to C, no process requires more than min
rounds to decide. The paper then proves a corresponding lower bound stating that at least d +1 rounds are necessary to get a decision in the worst case when
(for
and
).
This paper is based on the DISC’03 and DISC’04 conference versions MRR03,MRR04
A. Mostefaoui is currently Associate Professor at the Computer Science Department of the University of Rennes, France. He received his
Engineer Degree in Computer Science in 1990 from the University of Algiers, and a Ph.D. in Computer Science in 1994 from the
University of Rennes, France. His research interests include fault-tolerance and synchronization in distributed systems, group
communication, data consistency and distributed checkpointing. Achour Mostefaoui has published more than 70 scientific publications
and served as a reviewer for more than 20 major journals and conferences. Moreover, Achour Mostéfaoui is heading the software
engineer degree of the University of Rennes
S. Rajsbaum received a degree in Computer Engineering from the National Autonomous University of Mexico (UNAM) in 1985, and a PhD in
the Computer Science from the Technion, Israel, in 1991. Since then he has been a member of the Institute of Mathematics at
UNAM, where he is now a Full Professor with Tenure. He has been a regular visiting scientist at the Laboratory for Computer
Science of MIT. Also, he was a member of the Cambridge Research Laboratory of HP from 2000 to 2002. He was chair of the program
committee for Latin American Theoretical Informatics LATIN2002, and for ACM Principles of Distributed Computing PODC03, and
member of the Program Committee of various international conferences such as ADHOC, DISC, ICDCS, IPDPS, LADC, PODC, and SIROCCO.
His research interests are in the theory of distributed computing, especially issues related to coordination, complexity and
computability, and fault-tolerance. He has also published in graph theory and algorithms. Overall, he has published over fifty
papers in journals and international conferences. He runs the Distributed Computing Column of SIGACT News, the newsletter
of the ACM Special Interest Group on Algorithms and Computation Theory. He has been editor of several special journal issues,
such as the Special 20th PODC Anniversary Special Issue of Distributed Computing Journal (with H. Attiya) and of Computer
Networks journal special issue on algorithms.
M. Raynalhas been a professor of computer science since 1981. At IRISA (CNRS-INRIA-University joint computing research laboratory located
in Rennes), he founded a research group on Distributed Algorithms in 1983. His research interests include distributed algorithms,
distributed computing systems, networks and dependability. His main interest lies in the fundamental principles that underly
the design and the construction of distributed computing systems. He has been Principal Investigator of a number of research
grants in these areas, and has been invited by many universities all over the world to give lectures on distributed algorithms
and distributed computing. He belongs to the editorial board of several international journals. Professor Michel Raynal has
published more than 90 papers in journals (JACM, Acta Informatica, Distributed Computing, Comm. of the ACM, Information and
Computation, Journal of Computer and System Sciences, JPDC, IEEE Transactions on Computers, IEEE Transactions on SE, IEEE
Transactions on KDE, IEEE Transactions on TPDS, IEEE Computer, IEEE Software, IPL, PPL, Theoretical Computer Science, Real-Time
Systems Journal, The Computer Journal, etc.); and more than 190 papers in conferences (ACM STOC, ACM PODC, ACM SPAA, IEEE
ICDCS, IEEE DSN, DISC, IEEE IPDPS, Europar, FST&TCS, IEEE SRDS, etc.). He has also written seven books devoted to parallelism,
distributed algorithms and systems (MIT Press and Wiley). Michel Raynal has served in program committees for more than 70
international conferences (including ACM PODC, DISC, ICDCS, IPDPS, DSN, LADC, SRDS, SIROCCO, etc.) and chaired the program
committee of more than 15 international conferences (including DISC -twice-, ICDCS, SIROCCO and ISORC). He served as the chair
of the steering committee leading the DISC symposium series in 2002-2004. Michel Raynal received the IEEE ICDCS best paper
Award three times in a row: 1999, 2000 and 2001. He is a general co-chair of the IEEE ICDCS conference that will be held in
Lisbon in 2006. 相似文献
– | For values of consensus is solvable in an asynchronous system with t failures, and we obtain the known hierarchy of conditions that allows solving asynchronous consensus with more and more efficient protocols as we go from d = 0 to d = −t. |
– | For values of consensus is solvable in an asynchronous system with t failures, and we obtain the known hierarchy of conditions that allows solving asynchronous consensus with more and more efficient protocols as we go from d = 0 to d = −t. |
– | For values of d<0 consensus is known not solvable in an asynchronous system with t failures, but we obtain a hierarchy of conditions that allows solving synchronous consensus with protocols that can take more and more rounds, as we go from d = 0 to d = t. |
– | d = 0 is the borderline case where consensus can be solved in an asynchronous system with t failures, and can be solved optimally in a synchronous system. |
999.
Spatial Optimization Models for Water Supply Allocation 总被引:1,自引:0,他引:1
Alan T. Murray Patricia Gober Luc Anselin Sergio J. Rey David Sampson Paul D. Padegimas Yin Liu 《Water Resources Management》2012,26(8):2243-2257
Climate change is likely to result in increased aridity, lower runoff, and declining water supplies for the cities of the
Southwestern United States, including Phoenix. The situation in Phoenix is particularly complicated by the large number of
water providers, each with its own supply portfolio, demand conditions, and conservation strategies. This paper details spatial
optimization models to support water supply allocation between service provider districts, where some districts experience
deficits and others experience surpluses in certain years. The approach seeks to reconcile and integrate projections derived
from a complex simulation model taking into account current and future climate conditions. The formulated and applied models
are designed to help better understand the expected increasingly complex interactions of providers under conditions of climate
change. Preliminary results show cooperative agreements would reduce spot shortages that would occur even without climate
change. In addition, they would substantially reduce deficits if climate change were to moderately reduce river flows in Phoenix’s
major source regions, but have little effect under the most pessimistic scenarios because there are few surpluses available
for re-allocation. 相似文献
1000.