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21.
Forming coalitions and the Shapley NTU value 总被引:1,自引:0,他引:1
A simple protocol for coalition formation is presented. First, an order of the players is randomly chosen. Then, a coalition grows by sequentially incorporating new members in this order. The protocol is studied in the context of non-transferable utility (NTU) games in characteristic function form. If (weighted) utility transfers are feasible when everybody cooperates, then the expected subgame perfect equilibrium payoff allocation anticipated before any implemented game is the Shapley NTU value. 相似文献
22.
23.
Abstract The game theoretical analysis of international environmental problems has received increasing attention in recent years. Major issues are as follows. Under which conditions will an international environmental agreement (IEA) be signed? Will the agreement be stable? Game theory has given different answers to these questions; in particular, it is possible to show that if countries are myopic then only small stable coalitions occur, but if they are farsighted then both large and small stable coalitions exist. This paper studies the size of a farsighted stable IEA by considering a quadratic cost function in a pollution abatement model. Following Rubio and Ulph [2006] , we consider both the case of non‐negative emissions as well as the case of unrestricted ones. 相似文献
24.
25.
Cathy J. Ridgway Patrick A. C. Gane Abd El-Ghany El Abd Andrzej Czachor 《Transport in Porous Media》2006,63(3):503-525
Two different porous building materials have been previously measured and analysed (El-Abd and Milczarek, 2004, IEEE Trans. Nuclear Sci.; El-Abd et al., 2004, J. Phys. D) using neutron radiography to measure the water front position over time. The results from this experimental approach show
a similar behaviour to the predictions from idealised model structures, in that there is a cross over point where the fastest
rate of absorption at first favours the finer structure material and at later times favours the coarser pore structure material.
The computer model, Pore-Cor** is used to generate the idealised structures and the absorption of fluid into porous structures
follows a Bosanquet wetting algorithm for fluids undergoing both inertial and viscous dynamical flow (Ridgway and Gane, 2002,
Colloids Surfaces A: Physicochem. Eng. Aspects 206, 217–239.). The model structures comprise cubic pores connected by cylindrical throats on a three-dimensional 10× 10× 10
position matrix simulating the void structure of porous media by fitting as closely as possible the modelled mercury intrusion
curve to that of the experimentally determined mercury intrusion curve of the actual sample. They show the transition that
occurs in the absorption behaviour from the linear t-dependent short timescale inertial regime to the familiar √t Lucas-Washburn viscous regime. The simulated absorption algorithm applied to these model structures also shows a fluid position
behaviour that replicates qualitatively, given the limitation of representative sample volume, the cross over seen experimentally.
Furthermore, the existence of a preferred wetting path is demonstrated in the experimental as well as the model wetting front
behaviour. In the case of the structure containing the broader range of pore sizes, the wetting front is considered to proceed
by a network of optimal size combinations (inertial wetting versus viscous drag) and connectivity, leaving some pores behind
the wetting front unfilled or only partially filled.
** Pore-Cor is a software program of the Environmental and Fluids Modelling Group, University of Plymouth, Devon, PL4 8AA,
U.K. 相似文献
26.
Dirk Stueber Anil K. Mehta Zhiyun Chen Karen L. Wooley Jacob Schaefer 《Journal of Polymer Science.Polymer Physics》2006,44(19):2760-2775
Nearest‐neighbor chain packing in a homogeneous blend of carbonate 13C‐labeled bisphenol A polycarbonate and CF3‐labeled bisphenol A polycarbonate has been characterized using a shifted‐pulse version of magic‐angle spinning 13C{19F} rotational‐echo double‐resonance (REDOR) NMR. Complementary NMR experiments have also been performed on a polycarbonate homopolymer containing the same 13C and 19F labels. In the blend, the 13C observed spin was at high concentration, and the 19F dephasing or probe spin was at low concentration. In this situation, an analysis in terms of a distribution of isolated heteronuclear pairs of spins is valid. A comparison of the results for the blend and homopolymer defines the NMR conditions under which higher concentrations of probe labels can be used and a simple analysis of the REDOR results is still valid. The nearest neighbors of a CF3 on one chain generally include a carbonate group on an adjacent chain. A direct interpretation of the REDOR total dephasing for the polycarbonate blend indicates that at least 75% of carbonate‐carbon 13C ··· F3 nearest neighbors are separated by a narrow distribution of distances 4.7 ± 0.3 Å. In addition, analysis of the variations in REDOR spinning‐sideband dephasing shows that most of the 13C ··· F3 dipolar vectors have a preferred orientation relative to the polycarbonate mainchain axis. This combination of distance and orientational constraints is interpreted in terms of local order in the packing of the carbonate group of one polycarbonate chain relative to the isopropylidene moiety in a neighboring chain. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 2760–2775, 2006 相似文献
27.
This paper reviews tools which have great potential for reducing the difficulty of solving IP (and also MIP) problems, if
well implemented in solvers. Recent experiments with Branch and Bound solvers, in connection with “Short Start Features”,
have shown that implementations need and can still be improved. Concepts which are likely to be specially important for (0,1)
MIP are pointed out. 相似文献
28.
We consider the field, either gravitational or electric, associated to a macroscopic source. Tracing over the field's degrees
of freedom we show that the reduced density matrix diagonalizes on the position basis for macroscopic separations. The non
diagonal reduced density matrix elements are quenched by a factor which is independent of the body being at rest or in motion.
This may provide an explanation of the classical behavior of everyday objects not dissimilar to the one based on decoherence
by environment. We discuss a few examples which indicate that the electric field even in the case of a totally neutral body
is more effective, through a dipole contribution, than the gravitational field. 相似文献
29.
G. D. Puccini 《Foundations of Physics Letters》2003,16(5):481-494
A generalization of the classical electrodynamics for systems in absolute motion in presented using a possible alternative to the Lorentz transformation. The main hypothesis assumed in this work are: a) The inertial transformations relate two inertial frames: the privileged frame S and the moving frame S with velocity v with respect to S. b) The transformation of the fields from S to the moving frame S is given by H = a(H – v × D) and E = a(E + v × B), where a is a matrix whose elements depend of the absolute velocity of the system. c) The constitutive relations in the moving frame S are given by D = E, B = H and J = E. It is found that Maxwell's equations, which are transformed to the moving frame, take a new form depending on the absolute velocity of the system. Moreover, differing from classical electrodynamics, it is proven that the electrodynamics proposed explains satisfactorily the Wilson effect. 相似文献
30.
H. L. Logan Jr. 《Journal of Optimization Theory and Applications》1974,13(2):186-202
There are many interesting situations which can be described by anN-person general-sum differential game. Such games are characterized by the fact that the strategy of each player depends upon reasonable assumptions about the strategies of the remaining players; and, thus, these games cannot be considered asN uncoupled optimal control problems. In such cases, we say that the game is not strictly competitive, but involves a mutual interest which makes it possible for all of the players to reduce their costs by cooperating with one another, provided the resulting agreement can be enforced. When cooperation is allowed and there are more than two players, there is always the question of whether all possible subcoalitions will be formed with equal ease. This work considers the situation in which a particular subcoalition is preferred. A theory of general-sum games with preferred coalitions is presented, together with constructive examples of alternative approaches which are unsatisfactory. 相似文献