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AbstractIndustry 4.0 aims at providing a digital representation of a production landscape, but the challenges in building, maintaining, optimizing, and evolving digital models in inter-organizational production chains have not been identified yet in a systematic manner. In this paper, various Industry 4.0 research and technical challenges are addressed, and their present scenario is discussed. Moreover, in this article, the novel concept of developing experience-based virtual models of engineering entities, process, and the factory is presented. These models of production units, processes, and procedures are accomplished by virtual engineering object (VEO), virtual engineering process (VEP), and virtual engineering factory (VEF), using the knowledge representation technique of Decisional DNA. This blend of the virtual and physical domains permits monitoring of systems and analysis of data to foresee problems before they occur, develop new opportunities, prevent downtime, and even plan for the future by using simulations. Furthermore, the proposed virtual model concept not only has the capability of Query Processing and Data Integration for Industrial Data but also real-time visualization of data stream processing. 相似文献
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Interfacial hybridization kinetics of oligonucleotides immobilized onto fused silica surfaces 总被引:3,自引:0,他引:3
Jiang Zeng Amer Almadidy James Watterson Ulrich J. Krull 《Sensors and actuators. B, Chemical》2003,90(1-3):68-75
Fused silica optical fibers have been used in an intrinsic mode optical configuration as biosensors for fluorescence based detection of hybridization of nucleic acids. In this work, the kinetics of hybridization of single-stranded oligonucleotides that were covalently immobilized were studied. The probe DNA was dT20, and the target was Fluorescein-labeled non-complementary (dT20) or complementary (dA20) oligonucleotide. Chronofluorimetric monitoring of the adsorption and hybridization processes was used to investigate oligonucleotide films of different density, in different salt concentrations, at temperatures of 25 and 40 °C, with the concentration of the target DNA being 0.005–0.1 μM. Mathematical models based on first- and second-order Langmuir adsorption have been examined to describe both the adsorption and the hybridization processes. Experimental data were processed using the models, and the hybridization kinetics were calculated. Hybridization kinetics on these optical fiber DNA sensors was found to be up to three orders faster than results presented for a number of other experiments using different immobilization chemistries. 相似文献
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Recent advances in the realization of individual molecular‐scale devices [1,2] highlight the integration of individual devices into large‐scale functional circuits as the major challenge. DNA‐programmed assembly is a promising avenue in that direction due to the large amount of information that can be coded into the molecules and the ability to translate that information into physical constructs [3]. Large‐scale DNA‐templated electronics require, however, complex manipulation of double‐stranded DNA (dsDNA) molecules, as well as patterning of the electrical properties instilled to them by, e.g., metallization. To that end, sequence‐specific molecular lithography on single DNA molecules has been developed [4]. This was achieved by harnessing the exquisite homologous recombination process of the RecA protein. Sequence‐specific patterning of the metal coating of DNA molecules, localization of arbitrary labeled molecular objects at any desired dsDNA address without prior modifications, and generation of molecularly accurate stable dsDNA‐dsDNA junctions are demonstrated. The information encoded in the DNA molecules directs the lithographic process in analogy to the masks used in conventional microelectronics. The RecA protein provides the assembling capabilities, as well as the resist function. 相似文献
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Abstract The whole DNA of soybean was implanted into four varieties of wheat of Zhongyu5, Huaiyin 9628, Wenyou 1, Jimai 5 respectively via ion-beam mediation. There were 5 plantsobtained whose protein content was higher than 18.5%, the highest one was 21.44%. There were 3plants obtained whose protein content was lower than 11.5%, the lowest one was 10.96%. We cansee that the whole DNA of soybean transformed into wheat via ion beam implantation can inducethe increase in wheat protein content dramatically. The result also shows that the transformationefficiency of different gene types of wheat receptor varies greatly that the implanting time has acertain effect on the efficiency of transformation. 相似文献
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Double-stranded DNA is one of functional polymers, but the large amounts of DNA sources, such as salmon milt and shellfish gonads, have been discarded as industrial wastes. Therefore, conversion of this discarded DNA to be a useful material would be beneficial to utilize the unique property of DNA. These materials including DNA have been prepared by mixing with the organic polymers, such as alginic acid, collagen, and chitosan. However, since these materials have consisted from entirely organic components, these do not have the mechanical strength for a material. So, we prepared the organic-inorganic hybrid materials by mixing DNA with silane coupling reagents bis(trimethoxysilylpropyl)amine or bis[(3-trimethoxysilyl)propyl]ethylenediamine. These hybrid materials with the flexibility were water-insoluble and resistant to hydrolysis by nuclease. In addition, the mechanical strength of this hybrid material was approximately twice as high as that of DNA without mixing with silane coupling reagents. Furthermore, the double-stranded DNA in the hybrid materials has been maintained in a B-form structure in aqueous solution. Thus, we demonstrated the utilization of DNA as a functional material. As a result, this material could selectively accumulate harmful DNA-intercalating compounds with the planar structure, such as dibenzo-p-dioxin, dibenzofuran, and ethidium bromide. Organic-inorganic hybrid material including double-stranded DNA has potential to serve as a useful biomaterial for medical, engineering, and environmental applications. 相似文献
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ElectronmicroscopicobservationsandDNAchainfragmentationstudiesonapoptosisinbonetumorcelsinducedby153SmEDTMPZhuShouPeng,Xia... 相似文献
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Two experiments, with 80 undergraduates, replicated and extended research by R. T. Croyle and J. Cooper (see record 1984-11595-001) indicating that cognitive dissonance involves physiological arousal. In Exp I, Ss wrote counterattitudinal essays under conditions of high or low choice and, to assess arousal effects owing to effort, with or without a list of arguments provided by the experimenter. In high-choice conditions only and regardless of effort, Ss showed both arousal (heightened galvanic skin response) and attitude change. Arousal, however, did not decline following attitude change. The more effortful task (no arguments provided) produced increased arousal but not greater attitude change. In Exp II, the opportunity to change one's attitude following a freely chosen counterattitudinal essay was manipulated. As in Exp I, arousal increased following the essay but did not decline following a postessay attitude change opportunity. When Ss were not given an attitude change opportunity, however, arousal did decline. It is suggested that if dissonance is a drive state, drive reduction typically may be accomplished through gradual cognitive change or forgetting. (47 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献