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1 – 10 of over 4000Kinh Nguyen, Tharam S. Dillon and Erik Danielsen
This article proposes the concept of web clientserver event together with its associated taxonomy which yields a formal specification for such an event. The concept, in…
Abstract
This article proposes the concept of web clientserver event together with its associated taxonomy which yields a formal specification for such an event. The concept, in conjunction with the concept of atomic use case (reviewed in the article), is then used as a key element for a model‐driven approach to web information system development. The outcome is a new method for web information systems development that reduces the complex web‐based hypermedia navigation behaviour to a much simpler event‐driven behaviour. On the strength of that realized simplicity, the method provides (i) a set of platform‐independent models that completely characterizes the application, and (ii) a well‐defined process to map the combined model to any chosen platform‐dependent implementation.
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Develops an original 12‐step management of technology protocol and applies it to 51 applications which range from Du Pont’s failure in Nylon to the Single Online Trade Exchange…
Abstract
Develops an original 12‐step management of technology protocol and applies it to 51 applications which range from Du Pont’s failure in Nylon to the Single Online Trade Exchange for Auto Parts procurement by GM, Ford, Daimler‐Chrysler and Renault‐Nissan. Provides many case studies with regards to the adoption of technology and describes seven chief technology officer characteristics. Discusses common errors when companies invest in technology and considers the probabilities of success. Provides 175 questions and answers to reinforce the concepts introduced. States that this substantial journal is aimed primarily at the present and potential chief technology officer to assist their survival and success in national and international markets.
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Briefly reviews previous literature by the author before presenting an original 12 step system integration protocol designed to ensure the success of companies or countries in…
Abstract
Briefly reviews previous literature by the author before presenting an original 12 step system integration protocol designed to ensure the success of companies or countries in their efforts to develop and market new products. Looks at the issues from different strategic levels such as corporate, international, military and economic. Presents 31 case studies, including the success of Japan in microchips to the failure of Xerox to sell its invention of the Alto personal computer 3 years before Apple: from the success in DNA and Superconductor research to the success of Sunbeam in inventing and marketing food processors: and from the daring invention and production of atomic energy for survival to the successes of sewing machine inventor Howe in co‐operating on patents to compete in markets. Includes 306 questions and answers in order to qualify concepts introduced.
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Mica Grujicic, Jennifer Snipes and S. Ramaswami
The purpose of this paper is to introduce and analyze a new blast-wave impact-mitigation concept using advanced computational methods and tools. The concept involves the use of a…
Abstract
Purpose
The purpose of this paper is to introduce and analyze a new blast-wave impact-mitigation concept using advanced computational methods and tools. The concept involves the use of a protective structure consisting of bimolecular reactants displaying a number of critical characteristics, including: a high level of thermodynamic stability under ambient conditions (to ensure a long shelf-life of the protective structure); the capability to undergo fast/large-yield chemical reactions under blast-impact induced shock-loading conditions; large negative activation and reaction volumes to provide effective attenuation of the pressure-dominated shockwave stress field through the volumetric-energy storing effects; and a large activation energy for efficient energy dissipation. The case of a particular bimolecular chemical reaction involving polyvinyl pyridine and cyclohexyl chloride as reactants and polyvinyl pyridinium ionic salt as the reaction product is analyzed.
Design/methodology/approach
Direct simulations of single planar shockwave propagations through the reactive mixture are carried out, and the structure of the shock front examined, as a function of the occurrence of the chemical reaction. To properly capture the shockwave-induced initiation of the chemical reactions during an impact event, all the calculations carried out in the present work involved the use of all-atom molecular-level equilibrium and non-equilibrium reactive molecular-dynamics simulations. In other words, atomic bonding is not pre-assigned, but is rather determined dynamically and adaptively using the concepts of the bond order and atomic valence.
Findings
The results obtained clearly reveal that when the chemical reactions are allowed to take place at the shock front and in the shockwave, the resulting shock front undergoes a considerable level of dispersion. Consequently, the (conserved) linear momentum is transferred (during the interaction of the protective-structure borne shockwaves with the protected structure) to the protected structure over a longer time period, while the peak loading experienced by the protected structure is substantially reduced.
Originality/value
To the authors’ knowledge, the present work is the first attempt to simulate shock-induced chemical reactions at the molecular level, for purposes of blast-mitigation.
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A new and promising approach to document clustering consists of utilizing previously formed clusters of queries to cluster documents. To employ this approach in practice a…
Abstract
A new and promising approach to document clustering consists of utilizing previously formed clusters of queries to cluster documents. To employ this approach in practice a similarity measure for queries must be available. This requirement does not cause any problem in the case of information retrieval systems in which both the search request formulations and document representations are sets of weighted or unweighted index terms. However, in most operational retrieval systems search request formulations are Boolean combinations of index terms. Research into similarity measures for search request formulations of this type has already been undertaken by the author and reported elsewhere. The present paper provides further results of investigations in this area. The novelty of the approach discussed is the incorporation within the methodology described earlier of a weighting mechanism to indicate the relative importance of particular attributes of a given Boolean search request formulation. A modification suggested is based on the standard probabilistic approach to information retrieval.
WS‐ReliableMessaging specification describes a protocol that allows messages to be delivered reliably between distributed applications in the presence of software component…
Abstract
Purpose
WS‐ReliableMessaging specification describes a protocol that allows messages to be delivered reliably between distributed applications in the presence of software component, system, or network failures. However, it ensures reliable communication only in the context of two sites – it does not provide any means for consistent termination of the executions spanning over more than two sites. This paper aims to address this issue.
Design/methodology/approach
The paper presents the Reliable WS‐AtomicTransaction protocol, and illustrates its implementation by exploiting WS‐Coordination, which describes an extensible framework for providing protocols that coordinate the actions of distributed applications. The paper also presents the ontology of the log, which is maintained by the Reliable WS‐AtomicTransaction protocol. The ontology is presented in a graphical form and in OWL.
Findings
The introduction of an atomic commitment protocol and its termination protocol increase the reliability of the executions of distributed applications in service‐oriented architectures. On the other hand, it complicates the management of distributed applications as the atomic commitment protocol has to maintain the log that is used by its termination protocol.
Originality/value
The paper presents an atomic commitment protocol and its termination protocol, which is failure resilient and non‐blocking as long as a failed site can communicate with a process that has received sufficient information to know whether the transaction will be committed or aborted. Decreasing the amount of blockings is important because blocking can cause processes to wait for an arbitrarily long period of time.
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Raghu Garud, Joel Gehman and Peter Karnøe
At different points in time, energy harnessed from nuclear technology for commercial purposes has been qualified as atoms for peace, too cheap to meter, unsafe, sustainable, and…
Abstract
At different points in time, energy harnessed from nuclear technology for commercial purposes has been qualified as atoms for peace, too cheap to meter, unsafe, sustainable, and emission free. We explore how these associations – between nuclear technology (a category used in a descriptive way) and qualities such as emission free (a category used in an evaluative way) – are materially anchored, institutionally performed, socially relevant, and entrepreneurially negotiated. By considering all these factors, our analysis shows that it is possible to understand how and why categories and their meanings continue to change over time. We flesh out the implications of these observations and suggest avenues for future research.
Depending on the adopted principles of their domestic energy policy, individual countries responded in different ways to the information coming in from Japan. The majority of…
Abstract
Depending on the adopted principles of their domestic energy policy, individual countries responded in different ways to the information coming in from Japan. The majority of European countries having atomic power stations recommended inspection of the installations, particularly of those of older types. Discussion concerning the safety of nuclear installations also flared up. Opponents of the atomic power industry and environmentalists, asexpected, pointed to a need to lean energy production toward so-called renewable energy sources. This chapter explores public debate on the planned construction of nuclear power station in Poland in the aftermath of the Chernobyl and Japanese nuclear reactor explosions.
R. Sunyk and P. Steinmann
Continuum‐atomistic modeling denotes a mixed approach combining the usual framework of continuum mechanics with atomistic features like e.g. interaction potentials. Thereby, the…
Abstract
Continuum‐atomistic modeling denotes a mixed approach combining the usual framework of continuum mechanics with atomistic features like e.g. interaction potentials. Thereby, the kinematics are typically characterized by the so called Cauchy‐Born rule representing atomic distance vectors in the spatial configuration as an affine mapping of the atomic distance vectors in the material configuration in terms of the local deformation gradient. The application of the Cauchy‐Born rule requires sufficiently homogeneous deformations of the underlying crystal. The model is no more valid if the deformation becomes inhomogeneous. By virtue of the Cauchy‐Born hypothesis, a localization criterion has been derived in terms of the loss of infinitesimal rank‐1 convexity of the strain energy density. According to this criterion, a numerical yield condition has been computed for two different interatomic energy functions. Therewith, the range of the Cauchy‐Born rule validity has been defined, since the strain energy density remains quasiconvex only within the computed yield surface. To provide a possibility to continue the simulation of material response after the loss of quasiconvexity, a relaxation procedure proposed by Tadmor et al. [1] leading necessarily to the development of microstructures has been used. Alternatively to the above mentioned criterion, a stability criterion has been applied to detect the critical deformation. For the study in the postcritical region, the path‐change procedure proposed by Wagner and Wriggers [2] has been adapted for the continuum‐atomistics and modified.
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Mica Grujicic, Ramin Yavari, Jennifer Snipes, S. Ramaswami and Roshdy Barsoum
The purpose of this paper is to study the mechanical response of polyurea, soda-lime glass (glass, for short), polyurea/glass/polyurea and glass/polyurea/glass sandwich structures…
Abstract
Purpose
The purpose of this paper is to study the mechanical response of polyurea, soda-lime glass (glass, for short), polyurea/glass/polyurea and glass/polyurea/glass sandwich structures under dynamic-loading conditions involving propagation of planar longitudinal shockwaves.
Design/methodology/approach
The problem of shockwave generation, propagation and interaction with material boundaries is investigated using non-equilibrium molecular dynamics. The results obtained are used to construct basic shock Hugoniot relationships associated with the propagation of shockwaves through a homogeneous material (polyurea or glass, in the present case). The fidelity of these relations is established by comparing them with their experimental counterparts, and the observed differences are rationalized in terms of the microstructural changes experienced by the shockwave-swept material. The relationships are subsequently used to predict the outcome of the interactions of shockwaves with polyurea/glass or glass/polyurea material boundaries. Molecular-level simulations are next used to directly analyze the same shockwave/material-boundary interactions.
Findings
The molecular-level simulations suggested, and the subsequent detailed microstructural analyses confirmed, the formation of topologically altered interfacial regions, i.e. polyurea/glass and glass/polyurea interphases.
Originality/value
To the authors’ knowledge, the present work is a first attempt to analyze, using molecular-level simulation methods, the interaction of shockwaves with material boundaries.
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