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91.
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93.
A device design methodology for sub-100-nm SOC applications using bulk and SOI MOSFETs 总被引:1,自引:0,他引:1
CMOS for the mixed-mode applications has gained much interest recently. While the International Technology Roadmap for Semiconductors provides two different scaling guidelines for the analog and digital circuit operation using the bulk MOSFET, there are no well-defined scaling guidelines for improving the analog performance of silicon-on-insulator (SOI) MOSFETs. This paper presents a systematic and quantitative comparison between the analog characteristics of the bulk and SOI technology. The intrinsic gain, f/sub T/ and g/sub m//I/sub ds/ ratio are considered as a metric for this comparison. It is shown that, even for the operating frequencies in the range of gigahertz (where the ac kink effect is suppressed), analog performance of SOI devices is inferior to that of the bulk devices due to the capacitive drain-to-body coupling. Based on our study, we show that hat the gate-workfunction engineering (close to mid-gap workfunction) is essential in fully depleted SOI (FDSOI) devices for improving analog performance. The analog performance of partially depleted SOI (PDSOI) devices can be improved by using body-tied structures. An increased gate control in double-gate MOSFETs can provide very high output resistance for short-channel devices. 相似文献
94.
With video compression standards such as MPEG‐4, a transmission error happens in a video‐packet basis, rather than in a macroblock basis. In this context, we propose a semantic error prioritization method that determines the size of a video packet based on the importance of its contents. A video packet length is made to be short for an important area such as a facial area in order to reduce the possibility of error accumulation. To facilitate the semantic error prioritization, an efficient hardware algorithm for face tracking is proposed. The increase of hardware complexity is minimal because a motion estimation engine is efficiently re‐used for face tracking. Experimental results demonstrate that the facial area is well protected with the proposed scheme. 相似文献
95.
Hong Chae Woo 《Electronics letters》1998,34(13):1300-1301
The performance of a stochastic gradient adaptive filter can be significantly improved by introducing a forgetting factor. The complexity of the original algorithm can also be reduced by using only the signs of error signals and input signals in the gradient adaptive step size computation 相似文献
96.
La Porta Thomas F. Ramjee Ramachandran Woo Thomas Sabnani Krishan K. 《Mobile Networks and Applications》1998,3(2):123-141
Wireless networks are characterized by simple end devices and limited bandwidth. One solution to address these and other limitations
of the wireless mobile environment that has been widely pursued is the placement of proxies, or agents, inside the network
to assist with application processing that would normally take place on end devices. These agents can additionally manipulate
data to reduce bandwidth requirements and assist in providing services. The design and implementation of a user agent is heavily
impacted by the application it supports. In this paper we present our experiences with user agents in two different types
of applications: telephony-based Personal Communication Services (PCS) and two-way messaging. To provide low latency service,
the PCS user agents are mobile so that they may be kept close to their end devices. The design of the PCS agents limits migration
overhead to the transfer of approximately 100 bytes of information in about 150 milliseconds. To provide advanced messaging
services, the messaging user agent supports flexible messages while limiting air interface bandwidth usage. The messaging
agents reduce uplink bandwidth usage by approximately 35% when applied to a cellular PCS system, and reduce message payloads
by 97%.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
97.
The support of broadband multimedia applications over an enterprise network poses a broad range of networking challenges for efficient resource management, intelligent switching, and access control for distributed information. We propose two server-based scheduling algorithms, with low computational complexity, to guarantee multimedia information synchronization at the destination, with minimum presentation delays and buffer requirements. We outline a communication framework, highlighting the issues and challenges faced by today's enterprise networks to support multimedia services. We describe the proposed connection establishment and resource allocation schemes in resource-constrained enterprise networks. The objective is to manage the limited resources of the network for maximum utilization. Towards this end we present a dynamic capacity allocation scheme to support connections for multiple users. Specifically, we show that the channel capacity allocation problem can be formulated as a quadratic programming problem. This allocation scheme is implemented at each intermediate switch to dynamically determine the capacity allocation. The effects of interswitch rate mismatch and network delay offset scheduling have also been incorporated in the management framework. In addition, we introduce the concept of route selection based on the requested network quality of service 相似文献
98.
99.
To manage cost risk, prudent procurement of electric power requires that some portion of a buyer's energy demand be met through long-term contracting. Under cost-of-service regulation or performance-based regulation, a local distribution company (LDC) should be allowed to fully recover all prudently incurred power procurement costs. However, the regulatory test of prudence is an ex post review with the threat of disallowance. This paper presents an economic analysis of procurement prudence involving a small LDC, Bear Valley Electric Service (BVES), which serves a resort area in Southern California. The key findings are: (a) high and volatile prices and rolling blackouts characterized the market environment faced by the owner of BVES, Southern California Water Company (SCWC), at its signing of a 5-year fixed price contract; (b) SCWC was a price-taker with no incentive to act imprudently; (c) the contract was obtained via a competitive bidding process; (d) the contract price was comparable to the benchmark price of contemporaneous contracts; (e) the fixed price contract was economic when compared to available alternatives; and (f) despite (a)–(e), a negotiated settlement with the state regulator and a large user resulted in substantial disallowance. The policy implication is that a regulator should approve a prudent procurement plan proposed by an LDC to remove the unreasonable risk of an ex post review. If the LDC strictly adheres to the plan, the resulting electricity purchases are per se prudent and should entitle the LDC to full cost recovery. 相似文献
100.
Effect of surface modification of anode with surfactant on the performance of microbial fuel cell 下载免费PDF全文
Young‐Chae Song Dae‐Sup Kim Jung‐Hui Woo Bakthavachallam Subha Seong‐Ho Jang Subpiramaniyam Sivakumar 《国际能源研究杂志》2015,39(6):860-868
Surface modification of anode using surfactant has great influence on the electrical performance of a microbial fuel cell (MFC). In this study, the effect of surface‐modified exfoliated graphite used for anode fabrication on a cube‐type MFC batch reactor was examined. The surface exfoliated graphite was modified with 5‐mM anionic surfactant, sodium dodecyl sulfate. Anaerobic sludge used as inoculum containing 70% (v/v) of artificial wastewater and 30% (v/v) of seed sludge in an anode chamber and air cathode was used in cathode side. Anode modification was explored as an approach to enhance the start‐up and improve the performance of the reactor. Scanning electron microscopy was used to evaluate the morphology and activity of electrochemically active bacteria. In the study, the start‐up time of MFC required to approach stable voltage was substantially reduced, and the maximum stable voltage was higher than the control. In addition, the activation resistance of the MFC was considerably reduced, and the maximum power density (1640 mW/m2) was 20% higher than control. However, when the surface of exfoliated graphite was modified with over 10‐mM anionic surfactant, some negative effects on start‐up time, activation resistance and maximum power density were observed. This modification also enhanced the bacterial attachment and biofilm formation on the modified anode surface. The result suggested that surface modification anode with surfactant is effective for electrical responses achieved in the MFC. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献