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1.
Introducing new technology in a healthcare setting is a complex undertaking. In an environment in which accuracy, security, and reliability are critical elements, careful planning is the primary factor in ensuring a successful implementation. 相似文献
2.
We have developed an electronic classroom environment based on an analog/digital hybrid network, ComWeb. This environment supplements traditional methods of presentation by providing powerful communication tools between the students and the teacher directed from the instructor's workstation. The instructor can access every student's workstation at any time to monitor the student's work or to transmit information from any source. ComWeb has facilities for individual and group supervision. It can be adapted for teaching deaf or hard of hearing students in a mainstream environment. We describe the implementation of a ComWeb-based classroom at our site. The performance of students in conventional sections of a computer literacy course is compared with that in a section using ComWeb. For most of the material, performance of students in the ComWeb based section was markedly superior. 相似文献
3.
On the atmospheric pressure operation of secondary electron emission gaseous X-ray imaging detectors
A. Breskin R. Chechik I. Frumkin 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1996,380(3):562-567
Radiation-induced low-energy secondary electrons multiplied in gas by a series of wire electrodes provide an efficient means for fast and accurate radiation localization under very high flux. We discuss here the properties of secondary electron emission (SEE) X-ray detectors, operated at atmospheric pressure helium-based mixtures. 相似文献
4.
Marsha Ritzdorf 《Journal of Urban Affairs》1993,15(1):79-91
ABSTRACT: This paper argues that local land use planning needs to take its share of responsibility for social change in the community. Implicit in granting zoning powers to municipalities by the individual states is a mandate to use those powers in a socially responsible way. In those situations in which communities do not do so, many states are stepping in and responding to the needs of a growing constituency of people who feel that local land use planning is violating, not protecting, their rights to live in the community. Using child care as an example, this paper explores the growing use of state preemption of local control to achieve a socioland use purpose. 相似文献
5.
保证所有管道中石油从一端流向另一端不泄漏要比它的探测更加困难。比较图中的3个系统,可以看到这项技术在40多年来是如何逐步发展的。 相似文献
6.
Marsha Chechik Arie Gurfinkel Benet Devereux Albert Lai Steve Easterbrook 《Formal Methods in System Design》2006,29(3):295-344
Multi-valued logics provide an interesting alternative to classical boolean logic for modeling and reasoning about systems. Such logics can be used for reasoning about partially-specified systems, effectively encode vacuity detection and query-checking problems, help in detecting inconsistencies, and many others.In our earlier work, we identified a useful family of multi-valued logics: those specified over finite distributive lattices where negation preserves involution, i.e., for every element a of the logic. Such structures are called quasi-boolean algebras, and model-checking over these not only extends the domain of applicability of automated reasoning to new problems, but can also speed up solutions to some classical verification problems.Symbolic model-checking over quasi-boolean algebras can be cast in terms of operations over multi-valued sets: sets whose membership functions are multi-valued. In this paper, we propose and empirically evaluate several choices for implementing multi-valued sets with decision diagrams. In particular, we describe two major approaches: (1) representing the multi-valued membership function canonically, using MDDs or ADDs; (2) representing multi-valued sets as a collection of classical sets, using a vector of either MBTDDs or BDDs. The naive implementation of (2) includes having a classical set for each value of the algebra. We exploit a result of lattice theory to reduce the number of such sets that need to be represented.The major contribution of this paper is the evaluation of the different implementations of multi-valued sets, done via a series of experiments and using several case studies.
相似文献
Steve EasterbrookEmail: |
7.
Gurfinkel A. Chechik M. Devereux B. 《IEEE transactions on pattern analysis and machine intelligence》2003,29(10):898-914
Temporal logic query checking was first introduced by W. Chan in order to speed up design understanding by discovering properties not known a priori. A query is a temporal logic formula containing a special symbol ?/sub 1/, known as a placeholder. Given a Kripke structure and a propositional formula /spl phi/, we say that /spl phi/ satisfies the query if replacing the placeholder by /spl phi/ results in a temporal logic formula satisfied by the Kripke structure. A solution to a temporal logic query on a Kripke structure is the set of all propositional formulas that satisfy the query. Query checking helps discover temporal properties of a system and, as such, is a useful tool for model exploration. In this paper, we show that query checking is applicable to a variety of model exploration tasks, ranging from invariant computation to test case generation. We illustrate these using a Cruise Control System. Additionally, we show that query checking is an instance of a multi-valued model checking of Chechik et al. This approach enables us to build an implementation of a temporal logic query checker, TLQSolver, on top of our existing multi-valued model checker /sub /spl chi//Chek. It also allows us to decide a large class of queries and introduce witnesses for temporal logic queries-an essential notion for effective model exploration. 相似文献
8.
9.
Crowell Sheila E.; Beauchaine Theodore P.; Linehan Marsha M. 《Canadian Metallurgical Quarterly》2009,135(3):495
Over the past several decades, research has focused increasingly on developmental precursors to psychological disorders that were previously assumed to emerge only in adulthood. This change in focus follows from the recognition that complex transactions between biological vulnerabilities and psychosocial risk factors shape emotional and behavioral development beginning at conception. To date, however, empirical research on the development of borderline personality is extremely limited. Indeed, in the decade since M. M. Linehan initially proposed a biosocial model of the development of borderline personality disorder, there have been few attempts to test the model among at-risk youth. In this review, diverse literatures are reviewed that can inform understanding of the ontogenesis of borderline pathology, and testable hypotheses are proposed to guide future research with at-risk children and adolescents. One probable pathway is identified that leads to borderline personality disorder; it begins with early vulnerability, expressed initially as impulsivity and followed by heightened emotional sensitivity. These vulnerabilities are potentiated across development by environmental risk factors that give rise to more extreme emotional, behavioral, and cognitive dysregulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
Human and animal studies show that mammalian brains undergo massive synaptic pruning during childhood, losing about half of the synapses by puberty. We have previously shown that maintaining the network performance while synapses are deleted requires that synapses be properly modified and pruned, with the weaker synapses removed. We now show that neuronal regulation, a mechanism recently observed to maintain the average neuronal input field of a postsynaptic neuron, results in a weight-dependent synaptic modification. Under the correct range of the degradation dimension and synaptic upper bound, neuronal regulation removes the weaker synapses and judiciously modifies the remaining synapses. By deriving optimal synaptic modification functions in an excitatory-inhibitory network, we prove that neuronal regulation implements near-optimal synaptic modification and maintains the performance of a network undergoing massive synaptic pruning. These findings support the possibility that neural regulation complements the action of Hebbian synaptic changes in the self-organization of the developing brain. 相似文献