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排序方式: 共有261条查询结果,搜索用时 15 毫秒
1.
Researchers have been closely studying how information technology services became a routine part of our lives. Studies have found that users who routinely use online services either consciously develop loyalty or automatically develop a habit. But many studies now mix the elements of conscious and automatic use despite the great differences in these phenomena. This study proposes a new theoretical framework of how the conscious and automatic mechanisms simultaneously, but differentially, regulate postadoption phenomena in the context of online information services. An empirical test confirms that these two mechanisms have highly discernible patterns that researchers and managers alike must heed.  相似文献   
2.
A model is for presented a three-terminal MOS varactor for RF applications. The accuracy of the MOS varactor model is demonstrated by comparing simulation and measured device data at room and high temperatures. The relative mean error of the S-parameters between the measured and simulated data are less than 4%.  相似文献   
3.
This paper presents an automated procedure for generation of high-level topologies for continuous-time ΣΔ modulator system. A functional topology of the system is generated from the given transfer function model of the modulator. Mathematical transformation technique is applied iteratively over the initial topology to generate a functional topology which is optimized for modulator sensitivity, hardware complexity and relative power consumption. This is then implemented using behavioral models of operational transconductance amplifiers and capacitors. The generated high-level topology is ensured to work with reasonable accuracy under non-ideal conditions. The entire procedure has been implemented in Matlab/Simulink environment. Numerical results have been provided to demonstrate the procedure.  相似文献   
4.
Telecommunication Systems - Internet of Things (IoT) has changed the way people live by transforming everything into smart systems. Wireless Sensor Network (WSN) forms an important part of IoT....  相似文献   
5.
Wireless Personal Communications - In wireless communication channels, the signals arriving at the receiver may be of stochastic nature or be superpositioned due to non-uniform scattering and...  相似文献   
6.
Biocatalysis utilizes enzymes and microbial cells as catalysts for a wide range of applications in biotechnology. Immobilization of biocatalysts on various materials has several advantages, including the capacity for reuse, quick reaction termination, easy biocatalyst recovery and operational stability. The present article focuses on the use of material supports for developing immobilized biocatalysts in applications related to energy, environment and chemical synthesis. The work provides a comprehensive overview of a broad class of materials, including organic, inorganic and composites, that have been shown to be prosperous candidates to support the immobilization of enzymes and microbial cells. It also highlights the properties of nanomaterial support such as large surface area and comfort compartment for immobilization. The availability of different types of materials as catalyst support provides an opportunity to understand and develop efficient biocatalytic systems. The choice of selecting a catalyst support will mostly depend on the interaction of the material with the enzyme or microbial cell. Finally, potential challenges, future approaches in developing immobilized biocatalytic systems for various applications and novel material supports are suggested. © 2022 Society of Chemical Industry (SCI).  相似文献   
7.
The initial microorganism adhesion on substrate is an important step for biofilm formation. The surface properties of the silicone and Bacillus cereus were characterized by the sessile drop technique. Moreover, the physicochemical properties (hydrophobicity; electron donor/electron acceptor) of surface adhesion and the impact of bio adhesion on the silicone were determined at different time of contact (3, 7, and 24?h). The results showed that the strain was hydrophilic (Giwi?=?3.37?mJ/m2), whereas the silicone has hydrophobic character (Giwi?=??68.28?mJ/m2). Silicone surface presents a weak electron-donor character (γ ??=?2.2?mJ/m2) conversely to B. cereus that presents an important electron donor-parameter (γ ??=?31.6?mJ/m2). The adhesion of B. cereus to silicone was investigated using environmental scanning electron microscope and image analysis was assessed with the Matlab® program. After 3?h of contact, the data analysis, confirmed the bio adhesion with an amount of 9.6105?cfu/cm2 adhered cells. After 24?h, the percentage of silicone covered reached 93%. Furthermore, despite the difference in hydrophohbicity, the interaction between B. cereus and substrata was favoured by the thermodynamic model of adhesion (ΔG adhesion ?<?0). The real time investigation of the effect of B. cereus adhesion on the physicochemical properties of silicone has revealed that the substrata becomes hydrophilic (θ°?=?47.3, ΔGiwi?=?23.7?mJ/m2), after 7?h of contact. This bio adhesion had also favoured the increase of electron donor/acceptor character of silicone (γ ??=?53.1?mJ/m2 and γ +?=?5.3?mJ/m2).  相似文献   
8.
Jena  Biswajit  Bhol  Krutideepa  Nanda  Umakanta  Tayal  Shubham  Routray  Soumya Ranjan 《SILICON》2022,14(6):3005-3012
Silicon - This work represents a unique GAA MOSFET with metal work-function variations (WFVs) and ferroelectric material as dielectric. A random distribution of metal grain (TiN) with grain size...  相似文献   
9.
Butyl rubber–strontium cerium titanate (BS) composites have been prepared by hot pressing. The tensile tests show that the BS composites are flexible. The dielectric properties of the composites have been investigated at 1 MHz and 5 GHz as a function of ceramic contents. The composite with volume fraction 0.43 of ceramic filler has a dielectric constant (εr) of 11.9 and dielectric loss (tan δ) 1.8 × 10?3 at 5 GHz. The measured values of εr are compared with the effective values calculated using different theoretical models. The thermal conductivity of the composites is found to increase with ceramic contents and reaches a value of 4.5 Wm?1 K?1 for maximum filler loading 0.43 volume fraction. The coefficient of thermal expansion of the composites decreases gradually with filler loading and reaches a minimum value of 30.2 ppm °C?1 at a volume fraction 0.43. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   
10.
Proficiency on underlying mechanism of rubber-metal adhesion has been increased significantly in the last few decades. Researchers have investigated the effect of various ingredients, such as hexamethoxymethyl melamine, resorcinol, cobalt stearate, and silica, on rubber-metal interface. The role of each ingredient on rubber-metal interfacial adhesion is still a subject of scrutiny. In this article, a typical belt skim compound of truck radial tire is selected and the effect of each adhesive ingredient on adhesion strength is explored. Out of these ingredients, the effect of cobalt stearate is found noteworthy. It has improved adhesion strength by 12% (without aging) and by 11% (humid-aged), respectively, over control compound. For detailed understanding of the effect of cobalt stearate on adhesion, scanning electron microscopy and energy dispersive spectroscopy are utilized to ascertain the rubber coverage and distribution of elements. X-ray photoelectron spectroscopy results helped us to understand the impact of CuXS layer depth on rubber-metal adhesion. The depth profile of the CuXS layer was found to be one of the dominant factors of rubber-metal adhesion retention. Thus, this study has made an attempt to find the impact of different adhesive ingredients on the formation of CuXS layer depth at rubber-metal interface and establish a correlation with adhesion strength simultaneously.  相似文献   
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