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51.
Deep submicron NMOSFETs with elevated source/drain (ESD) were fabricated using self-aligned selective epitaxial deposition and engineered ion implanted profiles in the elevated layers, Deeper source/drain (S/D) junctions give rise to improved drive current over shallower profiles when the same spacer thickness and LDD doping level are used, Shallower junctions, especially with the heavily-doped S/D residing in the elevated layer, give better immunity to drain-induced-barrier lowering (DLBL) and bulk punchthrough. Tradeoffs between short-channel behavior and drive current with regard to S/D junction depth and spacer thickness were further studied using process/device simulations to cover a broader range of structure parameters. Despite the existence of epi facets along the sidewall spacers, the elevated S/D could be used as a sacrificial layer for silicidation, without degradation of the low-leakage junctions. The effects of the elevated S/D doping profile on substrate current and hot-electron-induced degradation were measured and analyzed. The simulated results were used, for the first time, to define the range of spacer thickness and LDD doses that are required in order for the lightly-doped region in the elevated S/D to effectively suppress the lateral electric field  相似文献   
52.
A wireless sensor network (WSN) is a prominent technology that could assist in the fourth industrial revolution. Sensor nodes present in the WSNs are functioned by a battery. It is impossible to recharge or replace the battery, hence energy is the most important resource of WSNs. Many techniques have been devised and used over the years to conserve this scarce resource of WSNs. Clustering has turned out to be one of the most efficient methods for this purpose. This paper intends to propose an efficient technique for election of cluster heads in WSNs to increase the network lifespan. For the achievement of this task, grey wolf optimizer (GWO) has been employed. In this paper, the general GWO has been modified to cater to the specific purpose of cluster head selection in WSNs. The objective function for the proposed formulation considers average intra‐cluster distance, sink distance, residual energy, and CH balancing factor. The simulations are carried out in diverse conditions. On comparison of the proposed protocol, ie, GWO‐C protocol with some well‐known clustering protocols, the obtained results prove that the proposed protocol outperforms with respect to the consumption of the energy, throughput, and the lifespan of the network. The proposed protocol forms energy‐efficient and scalable clusters.  相似文献   
53.
Journal of Signal Processing Systems - This paper describes a field-programmable gate array (FPGA) implementation of a fixed-point low-density lattice code (LDLC) decoder where the Gaussian mixture...  相似文献   
54.
Wireless Personal Communications - This paper proposes an combined method for manifold preservation and Subspace Eigenvectors(SE) based regression in high dimensional (HD) images. We studied...  相似文献   
55.
56.
This paper describes the design and analysis of a low‐power medium access control (MAC) protocol for wireless/mobile ATM networks. The protocol – denoted EC‐MAC (energy conserving medium access control) – is designed to support different traffic types with quality‐of‐service (QoS) provisions. The network is based on the infrastructure model where a base station (BS) serves all the mobiles currently in its cell. A reservation‐based approach is proposed, with appropriate scheduling of the requests from the mobiles. This strategy is utilized to accomplish the dual goals of reduced energy consumption and quality of service provision over wireless links. A priority round robin with dynamic reservation update and error compensation scheduling algorithm is used to schedule the transmission requests of the mobiles. Discrete‐event simulation has been used to study the performance of the protocol. A comparison of energy consumption of the EC‐MAC to a number of other protocols is provided. This comparison indicates the EC‐MAC has, in general, better energy consumption characteristics. Performance analysis of the proposed protocol with respect to different quality‐of‐service parameters using video, audio and data traffic models is provided. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
57.
There is growing interest in understanding how emotion regulation affects adaptation. The present study examined expressive suppression (which involves inhibiting the overt expression of emotion) and how it affects a critical domain of adaptation, social functioning. This investigation focused on the transition to college, a time that presents a variety of emotional and social challenges. Analyses focused on 2 components of suppression: a stable component, representing individual differences expressed both before and after the transition, and a dynamic component, representing variance specific to the new college context. Both components of suppression predicted lower social support, less closeness to others, and lower social satisfaction. These findings were robustly corroborated across weekly experience reports, self-reports, and peer reports and are consistent with a theoretical framework that defines emotion regulation as a dynamic process shaped by both stable person factors and environmental demands. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
58.
Treatment of 6-O-p-tolylsulfonyl starch with anhydrous potassium fluoride in boiling 1,2-dihydroxyethane afforded deoxyfluorostarches (D. S. Fluorine 0.18). Reaction of starch with hydrofluoric acid in dimethyl sulfoxide at −30 °C gave deoxyfluorostarches of high fluorine content (D. S. Fluorine 0.91). Chlorodeoxystarches have been prepared by the reaction of corn starch with (chloromethylene) dimethylimminium chloride in N, N′-dimethyl-formamide.  相似文献   
59.
Different synthetic products currently available and which find wide application as lubricants, are described, and their merits and demerits compared with the mineral based lubricants are outlined. Some of the major synthetic lubricants used in Indian industries are identified. The Indian chemical industry's potential to meet some of the requirements of synthetic lubricants is discussed and the need to create additional facilities in India for the manufacture of certain critical products, is described.  相似文献   
60.
Starch from sal seeds cake was isolated, bleached and purified. Scanning electron microscopy of the starch showed round to oval shaped granules of the size 3.5 to 12.3 μm. The starch has more nitrogen, phosphorus, lipids, amylose and water binding capacity in comparison to the other starches of forest origin. Despite its low and seemingly restricted swelling, the sal starch is much more soluble at any particular degree of swelling. Paste viscosity curve showed no drop in viscosity after full gelatinisation had taken place, i. e. the paste is stable on continued cooking.  相似文献   
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