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101.
The postmortem examination of failed IT projects reveals that long before the failure there were significant symptoms or “early warning signs.” This article describes the top 12 people- related and project-related IT project risks, based on “early warning sign” data collected from a panel of 19 experts and a survey of 55 IT project managers. 相似文献
102.
George A Manganaris Vlasios Goulas Ariel R Vicente Leon A Terry 《Journal of the science of food and agriculture》2014,94(5):825-833
Small berry fruits are consumed because of their attractive colour and special taste, and are considered one of the richest sources of natural antioxidants. Their consumption has been linked to the prevention of some chronic and degenerative diseases. The term ‘berry fruits’ encompasses the so‐called ‘soft fruits’, primarily strawberry, currants, gooseberry, blackberry, raspberry, blueberry and cranberry. The objective of this review is to highlight the nutraceutical value of berries and to summarize the factors affecting berry fruit antioxidants. Particular attention is given to postharvest and processing operation factors that may affect fruit phytochemical content. The structure–antioxidant relationships for phenolic compounds – the main group of antioxidants in this fruit group – are presented and major areas for future research are identified. © 2013 Society of Chemical Industry 相似文献
103.
104.
Leon M. Hermans 《Water Resources Management》2011,25(1):373-393
International experiences with water policy and governance arrangements are shared through various international meetings
and reports. The underlying assumption is that these experiences provide useful information to policy makers who are looking
for ways to improve water resources management in their home country or region. However, little has been written about analytical
support for these potentially interested policy makers. They have to reach informed decisions about whether or not to initiate
a process of policy transfer, about which foreign experiences to consider and about what parts of those experiences to copy,
adapt, or reject. Providing such analytical support is complicated by the involvement of multiple actors in water resources
management, who do not necessarily agree on these decisions. This paper outlines an approach to offer analytical support to
these multiple actors in the initial phase of a policy transfer process. The approach is applied to the case of the Büyük
Menderes river basin in Turkey, where local policy makers were engaged in a policy transfer process related to the EU Water
Framework Directive. It is concluded that the outlined approach can be used to inform local policy makers, as it yielded new
and valid information in the case. In the absence of overriding political concerns, such information would lead to different
decisions in various phases of policy transfer, when compared to a process that lacks this analytical support. 相似文献
105.
J. Ponce de Leon 《Gravitation and Cosmology》2008,14(3):241-247
There are many ways of embedding a 4D spacetime in a given higher-dimensional manifold while satisfying the field equations.
In this work, we extend and generalize a recent paper by Mashhoon and Wesson (Gen. Rel. Grav. 39, 1403 (2007)) by showing different ways of embedding a solution to the 4D Einstein equations in vacuum with a cosmological
constant, in a Ricci-flat as well as anti-de Sitter 5D manifold. These embeddings lead to different physics in 4D, in particular,
to non-equivalent cosmological terms as functions of the extra coordinate. We study themotion of test particles for different
embeddings and show that there is a complete equivalence between several definitions of the effective mass of test particles
measured in 4D, obtained from different theoretical approaches like the Hamilton-Jacobi formalism and the least action principle.
For the case under consideration, we find that the effective mass observed in 4D is the same regardless of whether we consider
null or non-null motion in 5D. 相似文献
106.
Leon ŁUKASZEWICZ 《Journal of Automated Reasoning》1999,22(3):223-239
107.
A conference held five years ago this month served, among other things, to introduce the notion to a substantial representation from the community of experimental nuclear physicists that a stored program computer could be used as a powerful, flexible tool for extending the scope of, as well as for aiding in the detailed execution of their experimental programs. The appreciation of the possibilities which were raised were colored by a simultaneous apprehension. The physicists worried about how extensive an effort they would have to make, how intimately they would have to be involved in order to use a computer on-line to an experiment. In short - who was going to write the programs? The answer was, unfortunately, not long in coming - they were. The potential gains for some classes of users were such that they did not wish to leave the restricted world of wired-program analyzers which, after all, were sufficient unto their needs. For others, however, the ends justified the means of the task. This latter group set about creating the programs and, in fact, the systems of programs that were necessary. This paper discusses some of the programming approaches which are in use or are under development for handling all or some features of experiment procedures. Because this conference has reports directly by several of the users, the emphasis here will be to review and compare rather than describe any in great detail. 相似文献
108.
This paper concerns the exploitation of user transparent inherent parallelism of pure Prolog programs using program transformation. We describe a novel paradigmenumerate-and-filter for transforming generate-and-test programs for execution under the committed-choice model extended to incorporate multiple solutions based on set enumeration. The paradigm simulates OR-parallelism by stream AND-parallelism integrating OR-parallelism, AND-parallelism, and stream parallelism. Generate-and-test programs are classified into three categories:simple generate-and-test, recursively embedded generate-and-test, and deeply intertwined generate-and-test. The intermediate programs are further transformed to reduce structure copying and metacalls. Algorithms are presented and demonstrated by transforming the representative examples of different classes of generate-and-test programs to Flat Concurrent Prolog equivalents. Statistics show that the techniques are efficient.Funded in part by Cleveland Advanced Manufacturing Program through the State of Ohio as a part of its core research program grant to Center of Automation and Intelligent Systems Research, Case Western Reserve University and NSF equipment grant CDA-8820390 to Kent State University. 相似文献
109.
Reviews areas of special vulnerability and the legal penalties that may befall psychotherapists who improperly manage dangerous patients (DPs). General rules of malpractice are discussed. While ethical and professional principles are important in the management of DPs, emphasis is placed on legal principles. The potential pitfalls include the failure to report suspected child abuse, abandonment of DPs, the duty to refer, the duty to protect 3rd parties, the failure to commit, the negligent release of DPs from inpatient facilities, and the inadequate treatment of suicidal patients. Leading cases illustrate the legal points. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
J. Mustre de Leon R. de Coss A. Rubio-Ponce A. R. Bishop S. A. Trugman 《Journal of Superconductivity》1999,12(1):37-39
The effect of isotopic substitution in a model polaronic system is presented.We use a three-site many body electron–phonon model which includeselectronic correlations and electron–phonon interactions, showing thepresence of polaron tuneling for intermediate and strong couplings. Theisotopic substitution changes the dynamics of polaron tuneling. Additionallyin the intermediate electron–phonon coupling regime, relevant forhigh-T
c superconductors, a change in the local structure is predicted. Inthis regime, the isotopic shift of phonon excitations is consistent withresults of optical measurements of c-axis phonons in YBa2Cu3O7. 相似文献