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1.
We have performed numerical modeling of nanoscale dual-gate ballistic n-MOSFET's with ultrathin undoped channel, taking into account the effects of quantum tunneling along the channel and through the gate oxide. The results show that transistors with channel length as small as 8 nm can exhibit either a transconductance up to 4000 mS/mm or gate modulation of current by more than 8 orders of magnitude, depending on the gate oxide thickness. These characteristics make the sub-10-nm devices potentially suitable for logic and memory applications, though their parameters are rather sensitive to size variations 相似文献
2.
Nonlinear Modeling and Control of a Unicycle 总被引:2,自引:0,他引:2
A unicycle system is composed of a unicycle and a rider. This system is inherently unstable, but together with a skilled rider can be autonomously controlled and stabilized. A dynamical investigation, a control design and a numerical solution of a nonlinear unicycle autonomous model are presented. The use of a nonlinear model for the control design is shown in this paper to be of great importance. A three-rigid-body physical model was selected for the dynamical study of the system. In a linearized model important physical characteristics of the unicycle system disappear (e.g. interactions between the longitudinal and lateral systems are being neglected), and therefore it is not recommended to be used for the control design. A nonlinear control law, which replaces the rider in stabilizing the model, was derived in the present work, using a nonlinear unicycle model. A simulation study shows good performance of this controller. Time spectral element methods are developed and used for integrating the nonlinear equations of motion. The approach employs the time discontinuous Galerkin method which leads to A-stable high order accurate time integration schemes. 相似文献
3.
ISO 9000 is a management standard that provides customers with assurance that their registered suppliers have a consistent quality system to which they adhere. This paper draws on four sources to show how ISO 9000 can lead to performance improvement: 1) theories of induced innovation and improvisation; 2) the literature on ISO 9000; 3) a case study of a telecom company; and 4) a survey of 1,150 North American companies. We find that the extent to which ISO 9000 is associated with performance improvement depends on the level of its assimilation, and the degree to which an organization goes beyond the minimal requirements of the standard. 相似文献
4.
Y Naveh LM Lee-Ambrose DA Samuelson RJ Cousins 《Canadian Metallurgical Quarterly》1993,123(8):1389-1395
Acute intestinal inflammation was established in rats by intraluminal administration of acetic acid into loops of distal ileum, proximal jejunum or ascending colon. The study included two control groups of intact (untreated) rats and sham-operated (saline-treated) rats for each intestinal segment. A third group of rats received acetic acid. Histological evaluation demonstrated that acetic acid treatment induced a mild inflammatory response. Two days after treatment, zinc absorption was measured using ligated 10-cm loops of each segment in which 65Zn was injected intraluminally. 65Zn absorption by the ileum, jejunum and colon was markedly reduced in those rats in which inflammation was induced by acetic acid. The liver showed the highest uptake of radioisotope, but the relative tissue distribution generally followed the amount of absorption. The surgical procedure itself seemed to reduce zinc absorption. No changes in [3H]leucine absorption were observed between sham-operated and acetic acid-treated controls. There was no significant serosal-->luminal secretion of intramuscularly injected 65Zn in any of the studied segments. Therefore, based upon the data obtained, we conclude that acetic acid-induced intestinal inflammation reduces absorption of zinc by the small and large intestine, and that a surgical procedure (laparotomy) also reduces zinc absorption. The mechanism of this inflammation is such that malabsorption shows some specificity. 相似文献
5.
Multilayered polymer structures made of two transparent, hyperelastic thermoplastic polyurethanes (TPUs) have been studied. The sheets, made by co‐extrusion and layer multiplication techniques, exhibited “physical coloring”, where a preferred wavelength range was reflected and visualized, due to the refractive index difference and nanometric thicknesses of the alternating layers. The extrusion system comprises two extruders and a series of multiplying units, each doubling the number of layers, such that 12 multiplying units render 212 + 1+1 (= 8,193) layers. For a 0.8 mm‐thick die, the resulting layers after die swell are ~ 150 nm thick. The extrusion temperatures of both grades were adjusted to equilibrate the viscosities and thus stabilize the layers. TPUs are highly elastic, and large stretching ratios allow for significant reduction in thickness. Physical coloring developed in a controlled, reversible manner. The visual color correlates with elongation, and can be offset by choice of initial thickness. Both reflected and transmitted wavelengths change throughout the whole visible range. A model was developed to fit the reflectance data, by introducing a “stress–volume coefficient” due to volume changes during stretch. This model fits the data very well. Characterization by AFM and TEM showed few discontinuous layers and some defects in the structure, nevertheless the multilayer structure is demonstrated. POLYM. ENG. SCI., 59:112–119, 2019. © 2018 Society of Plastics Engineers 相似文献
6.
An active learning climate facilitates new knowledge acquisition by encouraging employees to ask questions, seek feedback, reflect on potential results, explore, and experiment. These activities, however, also increase a learner’s chances of erring. In high-reliability organizations, any error is unacceptable and may well be life threatening. The authors use the example of resident physicians to suggest that by adjusting the conditions of priority of safety and managerial safety practices, organizations can balance these potentially conflicting activities. Participants in the study were 123 residents from 25 medical wards. Results demonstrated that the positive linear relationship between priority of safety and safety performance, demonstrated in earlier studies, existed only when the active learning climate was low. When the active learning climate was high, results demonstrated a U-shaped curvilinear relationship between priority of safety and number of errors. In addition, high managerial safety practices mitigated the number of errors as a result of the active learning climate. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
SB Linhart R King S Zamir U Naveh M Davidson S Perl 《Canadian Metallurgical Quarterly》1997,16(3):874-880
Field trials were conducted in late April to early May of 1995 and 1996 in central Israel to assess the potential for controlling rabies in red foxes (Vulpes vulpes) and golden jackals (Canis aureus) by using vaccine-laden baits. Of the bait types which were field tested, polymer fish meal baits were selected as the most suitable for both species. Fish meal baits containing tetracycline hydrochloride, an oral biomarker, were distributed by four-wheel-drive vehicle at a density of approximately 30 baits/km2 in two test areas of 35 km2. Of the animals which were trapped and euthanized seven to ten days after treatment, 65% of foxes and 56% of jackals gave positive results when tested for the biomarker. These results indicate the potential effectiveness of oral rabies vaccination of these species in Israel and possibly elsewhere in the Middle East, where rabies is a problem in wild canids. 相似文献
8.
Z. Naveh 《Landscape and urban planning》1993,24(1-4)
In view of the alarming threats to our planet Earth and its natural and cultural diversity, the IUCN World Conservation Organization must broaden the scale of its efforts from the species and ecosystem level to the landscape level. For this purpose new, more comprehensive strategies and powerfuls tools, based on holistic landscape planning and dynamic conservation management, are urgently needed. The Mediterranean Basin, presently undergoing an alarming process of biological, cultural and scenic degradation can serve as a good example for these needs. Here, as elsewhere, almost all conservation efforts have been devoted to the protection of restricted areas such as nature reserves or parks without much regard for the fate of the open landscape as a whole and the need for the conservation and restoration of its great natural and cultural assets. In order to gain greater public awareness and apprehension of these threats, to change the attitudes of politicians and decision-makers, and to provide practical guidance for holistic, sustainable and multibeneficial land use planning and management, a new tool of ‘Red Books for Threatened Landscapes’ is offered. These should present in clear non-technical terms, with ample maps and illustrations, recent, adverse biological, ecological, cultural and socio-economic changes in highly valuable and not yet irreversibly despoiled landscapes and their future threats, and suggest alternative, sustainable land use strategies with sounder conservation and restoration options. The Western Crete study, is the first Mediterranean Red Book case study, carried out by a multinational and multidisciplinary team. It will serve as an important example for a Red Book blueprint, to be prepared by the IALE-IUCN-CESP Working Group on Red Books for Threatened Landscapes. 相似文献
9.
Raj Kumar Rossana Rauti Denis Scaini Merav Antman-Passig Ohad Meshulam Doron Naveh Laura Ballerini Orit Shefi 《Advanced functional materials》2021,31(46):2104887
Graphene unique physicochemical properties made it prominent among other allotropic forms of carbon, in many areas of research and technological applications. Interestingly, in recent years, many studies exploited the use of graphene family nanomaterials (GNMs) for biomedical applications such as drug delivery, diagnostics, bioimaging, and tissue engineering research. GNMs are successfully used for the design of scaffolds for controlled induction of cell differentiation and tissue regeneration. Critically, it is important to identify the more appropriate nano/bio material interface sustaining cells differentiation and tissue regeneration enhancement. Specifically, this review is focussed on graphene-based scaffolds that endow physiochemical and biological properties suitable for a specific tissue, the nervous system, that links tightly morphological and electrical properties. Different strategies are reviewed to exploit GNMs for neuronal engineering and regeneration, material toxicity, and biocompatibility. Specifically, the potentiality for neuronal stem cells differentiation and subsequent neuronal network growth as well as the impact of electrical stimulation through GNM on cells is presented. The use of field effect transistor (FET) based on graphene for neuronal regeneration is described. This review concludes the important aspects to be controlled to make graphene a promising candidate for further advanced application in neuronal tissue engineering and biomedical use. 相似文献
10.
C. Jacobsen Z. Naveh T. Avi‐Itzhak 《The International journal of environmental studies》2013,70(4):263-270
It is argued that the problems of environmental pollution, and those of the inadequacy of formal social control mechanisms in contemporary societies are the unintended dysfunctional consequences of two separate but interrelated clusters of change processes. Consequently, solutions to the former require a thorough study of the latter in their relation to behaviour of individuals vis a vis the physical environment in public places. A survey of all 332 kibbutzim in Israel, conducted in 1973, assessed the level of “active care” (i.e. landscaping, lawns, trees, etc.) and “cleanliness” (i.e. absence of litter, refuse, etc.) found in eleven different locations in each kibbutz. Although kibbutzim are generally considered rural settlements, the data showed a typically urban reliance on “the authorities” to take care of the appearance of public places. Further analysis indicated that at least three variables are systematically related to this normative pattern: residential instability, age of settlement, and population size. Other background variables considered and analyzed were not found to be statistically related to active care and cleanliness. 相似文献