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71.
Vladimir Brailovski Patrick Terriault Sergei Prokoshkin 《Journal of Materials Engineering and Performance》2002,11(6):614-621
Shape memory alloys (SMA) suffer from the same impairing mechanisms experienced during cycling loading by classic alloys.
Moreover, SMA fatigue behavior is greatly influenced by thermomechanical cycling through the zone of thermoelastic phase transformation,
which is the basis of shape memory and superelasticity effects. Since the fatigue resistance of any material can be improved
by an appropriate thermomechanical treatment, in the present work combined differential scanning calorimetry and microhardness
testing were used to determine an optimum annealing temperature for the cold-worked Ni-50.1%Ti alloy. The optimization is
based on the assumption that latent heat of transformation is proportional to the mechanical work generated by SMA upon heating,
while material hardness is related to the yield stress of the material. It is supposed that an optimum trade-off in these
two properties guarantees the best dimensional and functional stability of SMA devices. The level and stability of the mechanical
work generated by the material during low-cycle fatigue testing are considered criteria for the material performance and thus
of the validity of the proposed optimization procedure. 相似文献
72.
Jörg Becker Patrick Delfmann Hanns-Alexander Dietrich Matthias Steinhorst Mathias Eggert 《Information Systems Frontiers》2016,18(2):359-405
Given the strong increase in regulatory requirements for business processes the management of business process compliance becomes a more and more regarded field in IS research. Several methods have been developed to support compliance checking of conceptual models. However, their focus on distinct modeling languages and mostly linear (i.e., predecessor-successor related) compliance rules may hinder widespread adoption and application in practice. Furthermore, hardly any of them has been evaluated in a real-world setting. We address this issue by applying a generic pattern matching approach for conceptual models to business process compliance checking in the financial sector. It consists of a model query language, a search algorithm and a corresponding modelling tool prototype. It is (1) applicable for all graph-based conceptual modeling languages and (2) for different kinds of compliance rules. Furthermore, based on an applicability check, we (3) evaluate the approach in a financial industry project setting against its relevance for decision support of audit and compliance management tasks. 相似文献
73.
Eric?ZimmerlingEmail author Patrick?J.?H?flinger Philipp G.?Sandner Isabell M.?Welpe 《Information Systems Frontiers》2016,18(6):1063-1084
This study develops a system framework and an enterprise IT solution for integrating gamification elements to efficiently implement and continuously perform Cost Engineering. Cost Engineering is a systematic approach to manage knowledge and competencies regarding costs reduction measures throughout the life cycle of products and is technology, resource and time intensive. Gamification as a non-monetary multidimensional incentive system holds great potential to implement and establish Cost Engineering in a novel and less resource demanding manner and stipulate knowledge sharing and dissemination. Building on a review of the relevant literature we conducted 20 interviews with experts from eight companies of the German and Austrian high-tech manufacturing industry to examine the system requirements from an organizational perspective. Analyzing the interviews, we found that companies need a flexible platform where the game elements help to align management objectives with concrete tasks, meet legislative regulations and have different evaluation methods. Our proposed system framework combines the organizational and IT requirements with gamification elements to efficiently steer Cost Engineering methods and best manage knowledge and competencies. 相似文献
74.
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76.
Maeda N Wells D Becker NC Hartley PG Wilson PW Haymet AD Kozielski KA 《The Review of scientific instruments》2011,82(6):065109
Nucleation in a supercooled or a supersaturated medium is a stochastic event, and hence statistical analyses are required for the understanding and prediction of such events. The development of reliable statistical methods for quantifying nucleation probability is highly desirable for applications where control of nucleation is required. The nucleation of gas hydrates in supercooled conditions is one such application. We describe the design and development of a high pressure automated lag time apparatus (HP-ALTA) for the statistical study of gas hydrate nucleation and growth at elevated gas pressures. The apparatus allows a small volume (≈150 μl) of water to be cooled at a controlled rate in a pressurized gas atmosphere, and the temperature of gas hydrate nucleation, T(f), to be detected. The instrument then raises the sample temperature under controlled conditions to facilitate dissociation of the gas hydrate before repeating the cooling-nucleation cycle again. This process of forming and dissociating gas hydrates can be automatically repeated for a statistically significant (>100) number of nucleation events. The HP-ALTA can be operated in two modes, one for the detection of hydrate in the bulk of the sample, under a stirring action, and the other for the detection of the formation of hydrate films across the water-gas interface of a quiescent sample. The technique can be applied to the study of several parameters, such as gas pressure, cooling rate and gas composition, on the gas hydrate nucleation probability distribution for supercooled water samples. 相似文献
77.
Bonenfant D Bourgeois FR Mimeault M Monette F Niquette P Hausler R 《Water science and technology》2011,63(12):2827-2832
Carboxymethylcellulose (CMC) and beta-cyclodextrin (beta-CD)-based polymers functionalized with two types of quaternary ammonium compounds (QACs), the alkaquat DMB-451 (N-alkyl (50% C14, 40% C12, 10% C10) dimethylbenzylammonium chloride) (DMD-451) named polymer DMB-451, and FMB 1210-8 (a blend of 32 w% N-alkyl (50% C14, 40% C12, 10% C10) dimethylbenzylammonium chloride and 48 w% of didecyldimethylammonium chloride) named polymer FMB 1210-8, were synthethized and characterized by Fourier transform infrared spectroscopy. The antimicrobial activities of these polymers against Eschericia coli were also evaluated at 25 degrees C in wastewater. The results have indicated that the polymer FMB 1210-8 possesses a high-affinity binding with bacterial cells that induces a rapid disinfection process. Moreover, in the same experimental conditions of disinfection (mixture of 1.0 g of polymer and 100 mL of wastewater), the polymer FMB 1210-8 has a higher antimicrobial efficiency (99.90%) than polymer DMB-451 (92.8%). This phenomenon might be associated to a stronger interaction with bacterial cells due to stronger binding affinity for E. coli cells and greater killing efficiency of the C10 alkyl chains QAC of polymer FMB 1210-8 to disrupt the bacterial cell membrane as compared to N-alkyl (50% C14, 40% C12, 10% C10) dimethylbenzylammonium chloride. Together, these results suggest that the polymer FMB 1210-8 could constitute a good disinfectant against Escherichia coli, which could be advantageously used in wastewater treatments due to the low toxicity of beta-CD and CMC, and moderated toxicity of FMB 1210-8 to human and environment. 相似文献
78.
Roberto D. Ponce Felipe Vásquez Alejandra Stehr Patrick Debels Carlos Orihuela 《Water Resources Management》2011,25(10):2449-2466
This paper presents a contingent valuation study concerning landscape impacts generated by the construction of one dam (Baker
1) of the HIDROAYSEN hydropower project located in the Chilean Patagonia. A survey was used to collect information about citizens’
opinions towards the hydropower project in four major cities in Chile. Specifically, a One-and-One-Half-Bound (OOHB) willingness
to pay eliciting format was applied to capture citizens’ WTP. The economic loss, associated to the landscape impacts for people
living in urban areas of the country, is found to be approximately US$ 205 million, which is nearly 28% of the total investment.
Our results also show that the cities’ distance from the dam affects citizens’ willingness to pay. 相似文献
79.
Arnaud Hubaux Patrick Heymans Pierre-Yves Schobbens Dirk Deridder Ebrahim Khalil Abbasi 《Software and Systems Modeling》2013,12(3):641-663
Feature diagrams have become commonplace in software product line engineering as a means to document variability early in the life cycle. Over the years, their application has also been extended to assist stakeholders in the configuration of software products. However, existing feature-based configuration techniques offer little support for tailoring configuration views to the profiles of the various stakeholders. In this paper, we propose a lightweight, yet formal and flexible, mechanism to leverage multidimensional separation of concerns in feature-based configuration. We propose a technique to specify concerns in feature diagrams and to generate automatically concern-specific configuration views. Three alternative visualisations are proposed. Our contributions are motivated and illustrated through excerpts from a real web-based meeting management application which was also used for a preliminary evaluation. We also report on the progress made in the development of a tool supporting multi-view feature-based configuration. 相似文献
80.
Current software and systems engineering tools provide only basic trace features, and as a result users are often compelled to construct non-trivial traceability queries using generic query languages such as SQL. In this paper, we present an alternative approach which defines traceability strategies for a project using UML class diagrams and then constructs trace queries as constraints upon subsets of the model. The visual trace modeling language (VTML) allows users to model a broad range of trace queries while hiding underlying technical details and data structures. The viability and expressiveness of VTML for use in a real project are demonstrated through modeling a broadly representative set of queries for a web-based health-care system. It is then evaluated through an experiment with human users to assess the readability and writability of VTML queries in comparison to generic SQL queries. We found that users read and constructed traceability queries considerably faster using VTML than using SQL. Furthermore, visually constructed traceability queries were substantially more correct compared to the same queries constructed with SQL. 相似文献