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41.
Jatinder N. D. Gupta Frank Werner Gunnar Wulkenhaar 《International Transactions in Operational Research》2003,10(3):267-294
This paper considers two-machine open shop problems with secondary criteria where the primary criterion is the minimization of makespan and the secondary criterion is the minimization of the total flow time, total weighted flow time, or total weighted tardiness time. In view of the strongly NP-hard nature of these problems, two polynomially solvable special cases are given and constructive heuristic algorithms based on insertion techniques are developed. A strongly connected neighborhood structure is derived and used to develop effective iterative heuristic algorithms by incorporating iterative improvement, simulated annealing and multi-start procedures. The proposed insertion and iterative heuristic algorithms are empirically evaluated by solving problem instances with up to 80 jobs. 相似文献
42.
Svensson S. Aronsson M. 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2003,33(4):562-571
Nowadays volume images are frequently used in many applications. Volume images of paper can be analyzed to increase the understanding of the complexity of the fiber network in paper and its effect on the optical and mechanical properties of paper. We show how curve and surface representations of the fiber, the fiber wall, and the fiber lumen can be computed using distance transform based algorithms. These representations are used for easy computation of wall thickness, degree of collapse, fiber length, slenderness ratio, fiber curl, and torsional resistance for the fibers. Free-fiber segments are identified, again using a distance transform based algorithm. Finally, we show tools for qualitative visual inspection of the fibers. The methods are evaluated and illustrated using both sets of synthetic and of real data. In addition to the analysis of the fiber network in paper, they can be used in many other applications where shape analysis of elongated objects is to be performed. 相似文献
43.
This paper describes support for flexibility, mobility and collaboration in engaging with, and making sense of, information. Our focus lies on the transitions people make between different, dynamic configurations of digital and physical materials, technologies, people and spaces. The technologies we describe have been developed in partnership with landscape architects over the past two years. We show that appliances and people can come together in a way that creates scope for such transitions, collaboration, and the emergence of new ways of working. 相似文献
44.
Andreas Hugerth Magnus Brisander Ulla Wrange Mikael Kritikos Björn Norrlind Marianne Svensson 《Drug development and industrial pharmacy》2013,39(2):185-196
ABSTRACTThe physicochemical properties of 1-benzenesulfonyl-4-(piperazin-1-yl)-indole hydrochloride, a novel 5-HT6 receptor antagonist for the treatment of obesity were characterized. Two solid state forms were identified at ambient conditions (23°C): an anhydrate form (1) and a hydrate form (2), with 1.5 moles of H2O. The latter easily dehydrates and rehydrates without affecting the crystal morphology. Investigations of the propensity for interconversion between the two forms reveal that a) conversion of 2→1 takes place above 145°C and that b) conversion of 1→2 only occurs after crystallization from supersaturated aqueous solutions at a water activity ≥0.94 or in the presence of comparable amounts of crystals of 2 in water at ambient conditions. However, in an equimolar suspension of 1 and 2 at 37°C no phase transformation was observed. Thus, the difference in chemical potential between the two forms is small. Form 1 was shown to have overall favorable solid state properties and, hence, considered the preferred form for continued pharmaceutical development. The characterization was performed by means of light microscopy, scanning electron microscopy, powder X-ray diffraction, FTIR/NIR-spectroscopy, differential scanning calorimetry, hot stage microscopy, thermogravimetry, dynamic vapor sorption, Karl Fischer water content determination, phase stability studies of suspensions, solubility, and intrinsic dissolution rate measurements. 相似文献
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48.
T. Jonsson N. Folkeson M. Halvarsson J.-E. Svensson L.-G. Johansson 《Oxidation of Metals》2014,81(5-6):575-596
This paper investigates the influence of 500 ppm HCl in a 5 %O2–95 %N2 atmosphere on the oxidation of the austenitic stainless steel AISI 310S at 500 °C. Laboratory exposures were made for one, 24, 72 and 168 h and the samples were analysed with XRD, SEM/EDX, FIB and TEM/EDX. When exposed in oxygen a thin and protective chromium-rich oxide scale forms. Addition of HCl causes significantly accelerated corrosion. Within the first hour of exposure, accumulations of FeCl2, CrCl2 and NiCl2 forms below the chromium-rich oxide, especially at steel grain boundaries. The chlorine-induced corrosion is suggested to occur through an electrochemical reaction, in which the dissociation of HCl to form chloride ions at the scale surface is coupled to the oxidation of the metal surface beneath the scale by an outwards electronic current and inwards diffusion of chloride ions along oxide grain boundaries. 相似文献
49.
Gunnar Jacobson 《Datenschutz und Datensicherheit - DuD》2016,40(4):217-221
Digitale Zertifikate werden bereits in großem Umfang zur Verschlüsselung mit Desktop Clients wie Outlook eingesetzt. Damit ein Benutzer auch an all seinen Mobilgeräten verschlüsselte E-Mails lesen und an beliebige Empfänger verschlüsseln kann, müssen sein privater Schlüssel sowie die Zertifikate der Partner dort verfügbar sein. 相似文献
50.
Gunnar E. Wolf 《Cryptologia》2017,41(5):459-475
In this article the authors present a trust management scheme, derived from the horizontal and almost anarchic web of trust model, but following a curatorship step that allows it to become a centerpiece for authentication in Debian, one of the largest and longest lived free software projects and producer of the eponymous GNU/Linux software distribution. This is done by analyzing the experience gained through a large-scale key migration process that spanned five years and nearly 100% of the originally existing keys, carried out attempting to minimize loss of keyring connectivity and strength, while keeping up to date with the best current security practices. 相似文献