The growth process of Fe/FeN multilayers prepared by rf sputtering is studied in situ, combining resistivity measurements and RHEED observations. The structural change from semi-continuous film with random orientation...
详细信息
The growth process of Fe/FeN multilayers prepared by rf sputtering is studied in situ, combining resistivity measurements and RHEED observations. The structural change from semi-continuous film with random orientation to continuous film with preferred orientation is detected during growth. Alternate growth of the (110)-oriented Fe layer and the (200)-oriented FeN layer are observed.
From a GF(q) sequence {a(i)}(i greater than or equal to 0) with period q(n)-1 we can obtain new periodic sequences {(a) over cap(i)$}(i greater than or equal to 0) with period q(n) by inserting one symbol b is an elem...
详细信息
From a GF(q) sequence {a(i)}(i greater than or equal to 0) with period q(n)-1 we can obtain new periodic sequences {(a) over cap(i)$}(i greater than or equal to 0) with period q(n) by inserting one symbol b is an element of GF(q) al the end of each period. Let b(0) = Sigma(i=0)(qn-2) a(i). It is first shown that the linear complexity of {<(a)over cap(i)>}(i greater than or equal to 0), denoted as LC({(a) over cap(i)$}), satisfies LC({(a) over cap(i)$}) = q(n) if b not equal -b(0) and LC({(a) over cap(i)$}) less than or equal to q(n)-1 if b = -b(0). Most of known sequences are shown to satisfy the zero sum property i.e., b(0) = 0. For such sequences satisfying b(0) = 0 it is shown that q(n)-LC({a(i)}) less than or equal to LC({(a) over cap(i)$}) less than or equal to q(n)-1 if b = 0.
From a sequence {a(i)}(i greater than or equal to 0) over GF(p) with period p(n)-1 we can obtain periodic sequence {}(i greater than or equal to 0) with period p(n)-2 by deleting one symbol at the end of each period. ...
详细信息
From a sequence {a(i)}(i greater than or equal to 0) over GF(p) with period p(n)-1 we can obtain periodic sequence {<(a)over tilde (i)>}(i greater than or equal to 0) with period p(n)-2 by deleting one symbol at the end of each period. We will give the bounds (upper bound and lower bound) of linear complexity of {<(a)over tilde (i)>}(i greater than or equal to 0) and {a(i)((j))}(i greater than or equal to 0), j is an element of GF(p)\{0}. For a binary m-sequence {a(i)}(i greater than or equal to 0) with period 2(n)-1, n-1 a prime, we wil give the explicit formula for the charasteristic polynomial of {<(a)over tilde (i)>}(i greater than or equal to 0).
Early and accurate diagnosis of brain tumors is crucial to improving patient outcomes and optimizing treatment strategies. Long-term brain injury results from aberrant proliferation of either malignant or nonmalignant...
详细信息
Cascading failures, such as bankruptcies and defaults, pose a serious threat for the resilience of the global financial system. Indeed, because of the complex investment and cross-holding relations within the system, ...
详细信息
The Turing machine model described by Hopcroft and Ullman (1969), with a 2-way, read-only input tape and a separate 2-way, read-write worktape, is considered. Ranjan, Chang, and Hartmanis (1991) introduced a slightly...
详细信息
The Turing machine model described by Hopcroft and Ullman (1969), with a 2-way, read-only input tape and a separate 2-way, read-write worktape, is considered. Ranjan, Chang, and Hartmanis (1991) introduced a slightly modified Turing machine model, called a 1-inkdot Turing machine. The 1-inkdot Turing machine is a Turing machine with the additional power of marking one tape cell on the input (with an inkdot). This tape cell is marked once and for all (no erasing), and no more than one dot of ink is available. The action of the machine depends on the current state, the currently scanned input and worktape symbols, and the presence of the inkdot on the currently scanned tape cell. The action consists of moving the heads and making appropriate changes on worktape cells (using the finite control). In addition, the inkdot may be used to mark the currently scanned cell on the input tape if it has not been used already.
Cholinergic input to the hippocampus originates in the septum and diagonal band. Guinea pig hippocampal slices in a bath of carbachol, a cholinergic agonist, displayed different patterns of rhythmical activities depen...
详细信息
Cholinergic input to the hippocampus originates in the septum and diagonal band. Guinea pig hippocampal slices in a bath of carbachol, a cholinergic agonist, displayed different patterns of rhythmical activities depending on the carbachol concentration. Exposure to 50 or 100 mu M led to intermittent induction of theta-like activities (TLAs). Long-term potentiation (LTP), induced by tetanus, was facilitated at concentrations within the optimum range for generating TLAs. This facilitation was blocked by the muscarinic receptor antagonist atropine. Augmentation of LTP during TLAs was greater than that during the rest period of TLAs which, in turn, was greater than that induced without activation of the muscarinic receptors. These results suggest that there are two muscarinic facilitation processes of LTP, one dependent on and the other independent of TLAs, with the former being more easily facilitated than the latter. (C) 1997 Elsevier science Ireland Ltd.
The fundamental solution is derived for the two-dimensional elastic field in a plane of two joined semi-infinite plates, one of which is isotropic and the other anisotropic. A concentrated force or dislocation is appl...
详细信息
The fundamental solution is derived for the two-dimensional elastic field in a plane of two joined semi-infinite plates, one of which is isotropic and the other anisotropic. A concentrated force or dislocation is applied at a point in the isotropic semi-infinite plate. A closed-form solution is obtained using the complex variable method. A special case of isotropic-orthotropic two-phase medium is deduced for the general solution including the case when the principal direction of elasticity of the orthotropic medium is not parallel to the interface of plates.
There have been numerous methods for learning and predicting time series ranging from the traditional time-series analyses to recent approaches using neural networks. A central issue common to all of them is the deter...
详细信息
There have been numerous methods for learning and predicting time series ranging from the traditional time-series analyses to recent approaches using neural networks. A central issue common to all of them is the determination of model structure. Both mean prediction error and An Information Criterion (AIC) are useful in model selection;the model with the smallest mean prediction error or AIC is selected from among a set of models as the best one. In this way they give a solution to the problem of model selection. Due to huge search space, however, the mean prediction error or AIC alone is not powerful enough to find the best model structure from among all the candidates. In the present paper the authors propose to use both a structural learning with forgetting and the mean prediction error or AIC to find a model with better generalization ability. Jordan networks and buffer networks, popular in the modeling of time series, are examined in this paper. The structural learning with forgetting and backpropagation (BP) learning are applied to compare the learning and prediction performance of these two types of models. Simulation results demonstrate that the structural learning with forgetting has better generalization ability than BP learning both in Jordan networks and buffer networks.
This paper investigates the plane problem of a crack normal to and terminating at a bimaterial interface. The general expression for the singular stress field at the crack tip that touches the interface is given in an...
详细信息
This paper investigates the plane problem of a crack normal to and terminating at a bimaterial interface. The general expression for the singular stress field at the crack tip that touches the interface is given in an explicit closed form. The singular stress fields are expressed as a sum of two independent terms, which correspond to the symmetric and skew-symmetric stress fields, respectively. The intensities of the symmetric and skew-symmetric singular stress fields are defined in terms of two factors K(I) and K(II), respectively. The body force method is used to determine the values of K(I) and K(II). The numerical results are given for a broad range of material combinations.
暂无评论