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排序方式: 共有4619条查询结果,搜索用时 109 毫秒
81.
To minimize costs in the manufacture of ring-shaped products, the ring-rolling process must be controlled efficiently. Toward this end, a recently developed control system allows nearly unattended operation of ring-rolling machines. The control system determines optimum preform geometry, thereby minimizing scrap; it also continuously monitors the process to adjust for deviations from set conditions. Various operations can be controlled, and process efficiency and quality are greatly improved. 相似文献
82.
Ulrich Stelzl 《Proteomics. Clinical applications》2013,7(11-12):727-732
Protein–protein interaction networks are typically generated in standard cell lines or model organisms as it is prohibitively difficult to record large interaction datasets from specific tissues or disease models at a reasonable pace. Although the interaction data are of high confidence, they thus do not reflect in vivo relationships as such. A wealth of physiologically relevant protein information, obtained under different conditions and from different systems, is available including information on genetic variation, protein levels, and PTMs. However, these data are difficult to assess comprehensively because the relationships between the entities remain elusive from the measurements. Here, we exemplarily highlight recent studies that gained deeper insight from genetic variation, protein, and PTM measurements using interaction information pointing toward the importance and potential of interaction networks for the interpretation of sequencing and proteomics data. 相似文献
83.
Rawn CJ Leeman JR Ulrich SM Alford JE Phelps TJ Madden ME 《The Review of scientific instruments》2011,82(2):024501
A fiber optic-based distributed sensing system (DSS) has been integrated with a large volume (72 l) pressure vessel providing high spatial resolution, time-resolved, 3D measurement of hybrid temperature-strain (TS) values within experimental sediment-gas hydrate systems. Areas of gas hydrate formation (exothermic) and decomposition (endothermic) can be characterized through this proxy by time series analysis of discrete data points collected along the length of optical fibers placed within a sediment system. Data are visualized as an animation of TS values along the length of each fiber over time. Experiments conducted in the Seafloor Process Simulator at Oak Ridge National Laboratory clearly indicate hydrate formation and dissociation events at expected pressure-temperature conditions given the thermodynamics of the CH(4)-H(2)O system. The high spatial resolution achieved with fiber optic technology makes the DSS a useful tool for visualizing time-resolved formation and dissociation of gas hydrates in large-scale sediment experiments. 相似文献
84.
Julia Heidemann Mathias Klier Andrea Landherr Steffen Zimmermann 《Electronic Markets》2013,23(1):73-84
In light of the growing relevance of customer-oriented business strategies IT investments in the field of Customer Relationship Management have increased considerably. However, firms often could not realize sufficient returns on these IT investments. One major reason for this failure seems to be the lack of appropriate approaches to determine the economic impact of such investments ex ante. Therefore, we develop an economic model to determine the optimal level of Customer Relationship Management IT investments. Using this approach, firms can evaluate, to what extent investments in Customer Relationship Management IT are reasonable. One major result is that in most cases the “all or nothing strategy” pursued by many firms does not lead to the optimal level of investments. To illustrate the practical utility and applicability of the approach, we provide a real world example of a German financial services provider. 相似文献
85.
Lina Zhou Ping Zhang Hans-Dieter Zimmermann 《Electronic Commerce Research and Applications》2013,12(2):61-68
Social commerce has quickly emerged as a new area of inquiry for both practitioners and researchers, suggesting the potential impacts of social media and social networking technologies and services in shaping commercial channels on and off the Internet. This essay starts by providing a brief overview of social commerce research and practice in light of the wide attention it has drawn in the industry. Then, we propose a research framework with an integrated view of social commerce that consists of four key components: business, technology, people, and information. The framework helps us understand the development of social commerce research and practice to date. Subsequently, we report some preliminary findings from a bibliometric study of academic and industry publications in social commerce to reveal recent trends and research topics, as well as some verification of the research framework. Finally, we discuss five articles in this special issue and categorize them in terms of the proposed social commerce research framework. 相似文献
86.
Gorka Epelde Eduardo Carrasco Gottfried Zimmermann Jan Alexandersson Robert Neßelrath Markus Dubielzig 《Universal Access in the Information Society》2013,12(1):73-87
This paper presents a new approach to make current and future television universally accessible. The proposed approach provides a means of universal accessibility both for remotely operating the TV set and for interacting with online services delivered through the TV. This proposal is based on the ISO/IEC 24752 “Universal Remote Console” (URC) standard. This standard defines an abstract user interface layer called the “user interface socket” and allows the development of pluggable (plug-in) user interfaces for any type of user and any control device. The proposed approach lays the foundation for the development of advanced user interfaces that can be interacted within various modalities. Different prototypes have been developed based on this approach and tested with end users. The user tests have shown this approach to be a viable option for the proposed scenarios. Based on the experience gathered with the prototypes, recommendations and implementation options are suggested for commercial adoption. 相似文献
87.
Zeolite based trace humidity sensor for high temperature applications in hydrogen atmosphere 总被引:1,自引:0,他引:1
We present a humidity sensor based on H-ZSM-5 type zeolite that is suitable to detect traces of humidity (10–110 ppmV) under harsh conditions, e.g. reducing atmosphere (H2) and high temperature (up to 600 °C). By means of complex impedance spectroscopy (IS) we show that the zeolite sensor responds linearly towards minimal changes in humidity. Therefore this result indicates that the zeolite sensor is capable to detect traces of humidity in processes where high temperatures in a hydrogen environment are required. 相似文献
88.
Scherer HU Wang J Toes RE van der Woude D Koeleman CA de Boer AR Huizinga TW Deelder AM Wuhrer M 《Proteomics. Clinical applications》2009,3(1):106-115
In several autoimmune disorders, including rheumatoid arthritis (RA), autoantibodies are thought to be the driving force of pathogenicity. Glycosylation of the Fc-part of human Igs is known to modulate biological activity. Hitherto, glycosylation of human IgG-Fc has been analyzed predominantly at the level of total serum IgG, revealing reduced galactosylation in RA. Given the pathogenic relevance of autoantibodies in RA, we wished, in the present study, to address the question whether distinct Fc-glycosylation features are observable at the level of antigen-specific IgG subpopulations. For this purpose, we have developed a method for the microscale purification and Fc-glycosylation analysis of anti-citrullinated peptide antibodies (ACPA). ACPA represent a group of autoantibodies that occur with unique specificity in RA patients. Their presence is associated with increased inflammatory disease activity and rapid joint destruction. Results indicate that ACPA of the IgG1 subclass vary considerably from total serum IgG1 with respect to Fc-galactosylation, with galactosylation being higher on ACPA than on serum IgG1 for some patients, while other patients show higher galactosylation on serum IgG1 than on ACPA. Using this method, studies can be performed on the biological and clinical relevance of ACPA glycosylation within RA patient cohorts. 相似文献
89.
Nesterov A König K Felgenhauer T Lindenstruth V Trunk U Fernandez S Hausmann M Bischoff FR Breitling F Stadler V 《The Review of scientific instruments》2008,79(3):035106
We examined the high precision deposition of toner and polymer microparticles with a typical size of approximately 10 microm on electrode arrays with electrodes of 100 microm and below using custom-made microelectronic chips. Selective desorption of redundant particles was employed to obtain a given particle pattern from preadsorbed particle layers. Microparticle desorption was regulated by dielectrophoretic attracting forces generated by individual pixel electrodes, tangential detaching forces of an air flow, and adhesion forces on the microchip surface. A theoretical consideration of the acting forces showed that without pixel voltage, the tangential force applied for particle detachment exceeded the particle adhesion force. When the pixel voltage was switched on, however, the sum of attracting forces was larger than the tangential detaching force, which was crucial for desorption efficiency. In our experiments, appropriately large dielectrophoretic forces were achieved by applying high voltages of up to 100 V on the pixel electrodes. In addition, electrode geometries on the chip's surface as well as particle size influenced the desorption quality. We further demonstrated the compatibility of this procedure to complementary metal oxide semiconductor chip technology, which should allow for an easy technical implementation with respect to high-resolution microparticle deposition. 相似文献
90.