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81.
The dead mother     
This study is not concerned, as the title might suggest, with the actual death of the mother but with the child's experience of a mother who is physically present but internally absent due to depression. The child simultaneously introjects and splits off the mother imago, making mourning and "burial" equally impossible. The consequence of this cathectic deprivation is what the author calls "psychic holes" or "white depression". Green attributes to the dead mother a similar structuring function for the psychic apparatus to that attributed to the dead father in Freud's Totem and Taboo, and places the dead mother complex side by side with the Oedipus complex.  相似文献   
82.
The representation of functions in a basis function expansionz(t)= k=1/=,a k> x k (t) is straightforward when the basis functionsx k (t) are orthogonal. There has been very little work up to this time in determining how to use nonorthogonal bases in signal representation. On the other hand, applications in data compression and signal synthesis often require using specific tailor-made bases. Presented here is a method for constructing very general nonorthogonal bases.Orthogonality has often been used to show that a basis spans the set of functions of interest and to calculate the coefficients of the representation. In this paper, both of these fundamental aspects are addressed for nonorthogonal bases. A new basis {y k (t)} is obtained by performing a linear transformation on a known existing basis {x k (t)}. This transformation is constructed such that the coefficients of signal representation on the new basis are readily found. Then, a useful and sufficient condition is placed upon the new basis such that representations converge.The fundamental methods are applied to the standard examples of signal representation. The complex sinusoids, the Rademacher functions, the orthogonal polynomials, and the decaying exponentials are used as the original basis {x k (t)} from which a new basis {y k (t)} is generated. Two examples are given to illustrate general applications: one in signal synthesis and one in signal analysis.  相似文献   
83.
84.
There is now a substantial body of work demonstrating that action video game experience results in enhancements in a wide variety of perceptual skills. More recently, several groups have also demonstrated improvements in abilities that are more cognitive in nature, in particular, the ability to efficiently switch between tasks. In a series of four experiments, we add to this body of work, demonstrating that the action video game player advantage is not exclusively due to an ability to map manual responses onto arbitrary buttons, but rather generalizes to vocal responses, is not restricted to tasks that are perceptual in nature (e.g. respond to a physical dimension of the stimulus such as its color), but generalizes to more cognitive tasks (e.g. is a number odd or even), and is present whether the switch requires a goal-switch or only a motor switch. Finally, a training study establishes that the relationship between the reduction in switch cost and action game playing is causal.  相似文献   
85.
We present a Bayesian approach to learning flexible safety constraints and subsequently verifying whether plans satisfy these constraints. Our approach, called the Safety Constraint Learner/Checker (SCLC), infers safety constraints from a single expert demonstration trace and minimal background knowledge, and applies these constraints to the solutions proposed by multiple planning agents in an integrated and heterogeneous ensemble. The SCLC calculates how much to blame plan fragments (partial solutions) generated by the individual planning agents. This information is used when composing these fragments into a final overall plan. In particular, fragments whose safety violations exceed a threshold are rejected. This facilitates the generation of safe plans. We have integrated the SCLC within the Generalized Integrated Learning Architecture, which was designed for Defense Advanced Research Projects Agency (DARPA)’s Integrated Learning (IL) program. The main goal of the IL program is to promote the development and success of sophisticated systems that learn to solve challenging real‐world problems based on a simple demonstration by a human expert and exiguous domain knowledge. We present experimental results showing the advantages of the SCLC on two multiagent problem‐solving tasks that were benchmark applications in DARPA’s IL program.  相似文献   
86.
The main features of a passive thin film display cell based on the electrochemically reversible formation of a tungsten bronze according to the reaction
(colourless) WO3 + xM+ + xe? ? MxWO3(blue)
where 0 < x < 1 are considered. Chemical analysis of an electrochemically coloured WO3 film has confirmed the presence of M. It is shown that a critical requirement of these cells is that Dτ(qCm/Q)2 ≈ 1, where the symbols are, in order, the M+ diffusion coefficient, the required device response time, the electronic charge, the maximum practical volume concentration of M in the WO3 film and lastly the area colouring charge. Typical energy requirements might be about 10 mJ cm?2 per complete cycle in a favourable case.Ionic injection overpotentials and ionic diffusion both appear to play a significant role in determining cell currents. Preliminary diffusion coefficient results for Li+ in r.f. sputtered WO3 films are reported, and their predicted dependence of film structure is discussed. The optical absorption of coloured WO3 films is presented, and it is interpreted as being predominantly due to free-electron intraband transitions.  相似文献   
87.
88.
Fault and attack management in all-optical networks   总被引:2,自引:0,他引:2  
Network management for optical networks faces additional security challenges that arise by using transparent optical network components in communication systems. While some available management mechanisms are applicable to different types of network architectures, many of these are not adequate for all-optical networks. These have unique features and requirements in terms of security and quality of service, thus requiring a much more targeted approach in terms of network management. In this article we consider management issues with particular emphasis on complications that arise due to the unique characteristics and peculiar behaviors of transparent network components. In particular, signal quality monitoring is still a major complication in all-optical networks. Despite new methods for detection and localization of attacks having been proposed, no robust standards or techniques exist to date for guaranteeing the quality of service in these networks. Therefore, sophisticated mechanisms that assist in managing and assessing the proper function of transparent network components are highly desirable. Accordingly, we present an algorithm for multiple attack localization and identification that can participate in some tasks for fault management of all-optical networks  相似文献   
89.
The first examples of mesostructured materials containing Mo- and W-oxo-sulphur species incorporated into a poorly ordered MCM-41 framework have been prepared under hydrothermal condition and alkaline medium. The incorporation of oxygen-sulphur derivates of molybdenum and tungsten not only increases significantly the pore diameter, but also improves the thermal stability of the MCM-41-related mesoporous material.  相似文献   
90.
Ni—MH电池充电效率与内压的相关行为   总被引:3,自引:2,他引:3  
Ni—MH电池充电过程中的内部压力是表征电池优劣的一个重要性能。本文通过对电池充电效率的测定以及一系列的理论推导和数学计算,得到了理论上的内压曲线。曲线的趋势与测定值相吻合。由此可以判定,内压升高的原因在于正极的析氧及负极氧还原速度的缓慢。并据此调整了负极配方,通过引入适当的添加剂,成功地降低了电池充电时的内压。  相似文献   
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