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131.
Linh Thao Ly Stefanie Rinderle-Ma Kevin G?ser Peter Dadam 《Information Systems Frontiers》2012,14(2):195-219
Key to broad use of process management systems (PrMS) in practice is their ability to foster and ease the implementation,
execution, monitoring, and adaptation of business processes while still being able to ensure robust and error-free process
enactment. To meet these demands a variety of mechanisms has been developed to prevent errors at the structural level (e.g., deadlocks). In many application domains, however, processes often have to comply with business level rules and
policies (i.e., semantic constraints) as well. Hence, to ensure error-free executions at the semantic level, PrMS need certain control mechanisms for validating
and ensuring the compliance with semantic constraints. In this paper, we discuss fundamental requirements for a comprehensive
support of semantic constraints in PrMS. Moreover, we provide a survey on existing approaches and discuss to what extent they
are able to meet the requirements and which challenges still have to be tackled. In order to tackle the particular challenge
of providing integrated compliance support over the process lifecycle, we introduce the SeaFlows framework. The framework
introduces a behavioural level view on processes which serves a conceptual process representation for constraint specification
approaches. Further, it provides general compliance criteria for static compliance validation but also for dealing with process
changes. Altogether, the SeaFlows framework can serve as formal basis for realizing integrated support of semantic constraints
in PrMS. 相似文献
132.
Till Schümmer Peter Tandler Joerg M. Haake 《Universal Access in the Information Society》2012,11(3):239-258
Meetings are an important form of interaction in business settings. However, meetings are often not held in a way that makes all participants feel engaged. Meeting support systems try to overcome this obstacle by helping meeting participants in the meeting workflow. This paper takes a complementary approach by distinguishing between different perspectives of good meetings: the peopleware perspective, the generic groupware perspective, and the roomware perspective. It is argued that all these perspectives have to be considered simultaneously when heading toward an ideal meeting system design. The paper presents excerpts of a pattern language that empowers users to improve their meeting. Besides this, the pattern language can be considered as a tool for the designer. After showing, how both groups made use of the patterns, the paper finally presents LivingAgendas, a meeting support system that can accompany the meeting participant through the meeting life cycle. 相似文献
133.
The Constraint Logic Programming Scheme defines a class of languages designed for programming with constraints using a logic programming approach. These languages are soundly based on a unified framework of formal semantics. In particular, as an instance of this scheme with real arithmetic constraints, the CLP() language facilitates and encourages a concise and declarative style of programming for problems involving a mix of numeric and non-numeric computation.In this paper we illustrate the practical applicability of CLP() with examples of programs to solve electrical engineering problems. This field is particularly rich in problems that are complex and largely numeric, enabling us to demonstrate a number of the unique features of CLP(). A detailed look at some of the more important programming techniques highlights the ability of CLP() to support well-known, powerful techniques from constraint programming. Our thesis is that CLP() is an embodiment of these techniques in a language that is more general, elegant and versatile than the earlier languages, and yet is practical.An earlier version of this paper appeared in the proceedings of the 4th International Conference on Logic Programming, Melbourne, May 1987. Much of this work was carried out while the authors were at Monash University, Melbourne, Australia. 相似文献
134.
Notes that 7 of the 10 top-cited articles in the Psychological Bulletin deal with methodological topics. One of these is the P. M. Bentler and D. G. Bonett (1980) article on the assessment of fit in covariance structure models. Some context is provided on the popularity of this article. In addition, a citation study of methodology articles appearing in the Bulletin since 1978 was carried out. It verified that publications in design, evaluation, measurement, and statistics continue to be important to psychological research. Some thoughts are offered on the role of the journal in making developments in these areas more accessible to psychologists. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
135.
Peter Steffen 《Circuits, Systems, and Signal Processing》1986,5(2):187-210
The concept of smoothing noisy data using appropriate polynomials turns out to be equivalent to the application of suitable nonrecursive digital filters having the following properties: They process the data in such a way that the moments are conserved up to a desired order while the energy of their impulse response is minimum. Flatness constraints of their frequency response at =0 are equivalent to the moment condition. By using orthogonal polynomials, an explicit solution is known from the literature. A second approach which uses a special decomposition also yields closed form solutions. The realization is simplified, especially in the case where a large number of moments is supposed to be conserved. 相似文献
136.
Ståhlkrantz Adam Hedström Peter Sarius Niklas Borgenstam Annika 《Metallurgical and Materials Transactions A》2022,53(9):3418-3427
Metallurgical and Materials Transactions A - Variant pairing in bainite was evaluated in four different commercial low alloy steels with medium to high carbon content. The steels investigated were... 相似文献
137.
138.
An examination of the influence of pressure and heating rate on the thermoplastic properties of a weakly coking coal and of coal with various pitch-like additives was carried out using a high pressure dilatometer. Pressure up to 4 MPa markedly increased the swelling properties and increased the plastic range by decreasing the softening temperature, but the effects of pressure were strongly influenced by rate of heating with high heating rates enhancing the effects. Additions of tar or pitch also enhanced swelling at low pressure. The solid carbonization residues from the dilatometer were examined by polarized light microscopy to determine the content and composition of optically anisotropic species. The anisotropic content was increased by increases in pressure and heating rate and pitch additives enhanced the anisotropic content, especially at low pressure, without affecting the composition of the anisotropy. No direct correlations exist between the dilatometric parameters and the optical anisotropy but their dependence on the conditions emphasizes that when considering high pressure gasification of coal, it is necessary to obtain data under appropriate conditions. 相似文献
139.
A series of iron oxide doped norbornene (NOR)/deuterated norbornene dicarboxylic acid (NORCOOH) diblock copolymers were synthesized and characterized by X-ray photoelectron spectroscopy (XPS), small angle neutron scattering (SANS) and superconducting quantum interference device (SQUID) experiments. γ-Fe2O3 nanoparticles were synthesized within the microdomains of diblock copolymers with volume fractions of NOR/NORCOOH 0.64/0.36, 0.50/0.50 and 0.40/0.60. A spherical nanoparticle morphology was displayed in the polymer with 0.64/0.36 volume fraction. Polymers with 0.50/0.50 and 0.40/0.60 volume fractions exhibited interconnected metal oxide nanostructures. The observed changes in the shape and peak positions of the small-angle neutron scattering profiles of polymers after metal doping were related to the scattering from the metal oxide particles and to the possible deformed morphologies due to the strong interparticle interactions between metal particles, which may influence the polymer microphase separation. The combined scattering from both polymer domains and magnetic particles was depicted in SANS profiles of metal oxide doped polymers. γ-Fe2O3 containing block copolymers were superparamagnetic at room temperature. An increase in the blocking temperature (Tb) of interconnected nanoparticles was observed and was related to the interparticle interactions, which depends on the average distance (d) between particles and individual particle diameter (2R). The sample with volume fraction of 0.4/0.6 have the lowest d/(2R) ratio and exhibit the highest Tb at 115 K. 相似文献
140.