This paper presents a new sch.me to estimate the user mobility by incorporating the aggregate history of mobile users and system parameters. With this approach, each user's position within the location area is dif...
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This paper presents a new sch.me to estimate the user mobility by incorporating the aggregate history of mobile users and system parameters. With this approach, each user's position within the location area is differentiated by zone partition for more accurate prediction. In order to provide the flexibility of tradeoff between quality demand and computation complexity, the estimation is adjusted dynamically according to the constraint of prediction order. Then an adaptive algorithm is developed to predict the future position of mobile terminals in terms of location probabilities, while considering each terminal's movement direction, residence time, and path information. Simulation results demonstrate that the signaling cost for location tracking under delay bound is greatly reduced based on the estimated user mobility pattern.
In spite of the proliferation of object-oriented design methodologies in contemporary software development, their application to real-time embedded systems has been limited because of the practitioner's conservati...
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ISBN:
(纸本)1581135270
In spite of the proliferation of object-oriented design methodologies in contemporary software development, their application to real-time embedded systems has been limited because of the practitioner's conservative attitude toward handling timing constraints. In fact, this conservative attitude is well-grounded because traditional priority-based sch.duling techniques cannot be straightforwardly integrated into them. The automated implementation from the object-oriented real-time designs usually incurs a large number of tasks which, under traditional priority-based sch.duling techniques, does not scale well due to excessive preemption overheads. Recently, preemption threshold sch.duling was introduced to reduce run-time multi-tasking overhead while improving sch.dulability by exploiting non-preemptibility as much as possible. Unfortunately, the preemption threshold sch.duling cannot be directly adopted into the object-oriented design methods due to the lack of real-time synchronization. In this paper, we present the essential basis of real-time synchronization for preemption threshold sch.duling. Specifically, we integrate the priority inheritance protocol, the priority ceiling protocol, and the immediate inheritance protocol into preemption threshold sch.duling. We also provide their sch.dulability analyses. Consequently, the integrated sch.me, which minimizes worst-case context switches, is appropriate for the automated implementation of real-time object-oriented design models.
In this paper we first review the method of computing Loss of Load Probability (LOLP) as a means of assessing reliability. Then, we relate the method to the Installed Capacity (ICAP) mechanisms, which are currently be...
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In this paper we first review the method of computing Loss of Load Probability (LOLP) as a means of assessing reliability. Then, we relate the method to the Installed Capacity (ICAP) mechanisms, which are currently being implemented in some regional US elec.ricity markets as a necessary market process for ensuring long term reliability. The basic conclusion of the paper is that the current ICAP mechanisms do not accurately ensure a desired level of reliability, as intended. The reason for this situation is because the current ICAP mechanisms consider the expected value of available generation, which is only the first order simplification of probabilistic generator capacity modeling, while ignoring the second and higher orders. We use simple examples to illustrate this claim and its implications. The incentives created through ICAP mechanisms directly impact the investment decisions of new generation and transmission. Therefore, the findings presented in the paper are critical as we move forward with the restructuring process. To achieve the desired level of reliability through market process, this paper may lead to understanding better the necessary modifications to the current ICAP mechanisms.
A new CMOS pixel which has lateral and vertical BJT structure is proposed The structure is good for the use of amplification at low light condition. To reduce fixed pattern noise (FPN), correlated double sampling (CDS...
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A new CMOS pixel which has lateral and vertical BJT structure is proposed The structure is good for the use of amplification at low light condition. To reduce fixed pattern noise (FPN), correlated double sampling (CDS) is used. It has high responsivity compared with the conventional CMOS photodiode pixel and has advantages at low voltage condition so that it is suitable for the advanced CMOS process.
This paper describes the potential of using corn cob as a primary energy source for elec.ricity generation in Thailand. Due to increase in energy demands, fuel cost, and environmental issues, the reliance of fossil fu...
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This paper describes the potential of using corn cob as a primary energy source for elec.ricity generation in Thailand. Due to increase in energy demands, fuel cost, and environmental issues, the reliance of fossil fuel has to be reduced. One of the alternatives is to utilize agricultural residues. This paper provides an overview of the availability of corn cob in Thailand and a description of a small-scaled biomass gasifier engine-generator. Based on literature research and estimation, over 1 GWh/year could be produced from this technique. This will provide subs tantial savings on fuel cost and reduction on environmental impacts. In addition to the generation of elec.ricity, this also provides a safe means to dispose the waste residues. This is an initial phase of an ongoing project to be undertaken in Phitsanulok, Thailand.
In this paper, the ground bounce noise due to internal gate switching is studied. It has been found that both power-rail and ground-rail pin impedances are important in evaluating internal ground bounces. Based on the...
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In this paper, the ground bounce noise due to internal gate switching is studied. It has been found that both power-rail and ground-rail pin impedances are important in evaluating internal ground bounces. Based on the lumped-model analysis taking into account the parasitic effects of MOS transistors, a novel analytical model is developed which accurately accounts for both power rail and ground rail pin impedances. The proposed model is compared with the previous work and validated by SPICE simulation results.
Energy-awareness indicates the scalability of the system energy with changing conditions and quality requirements. A novel technique, Signal Bypassing and Zero Insertion, to design energy-aware multiplier in multi-rai...
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Energy-awareness indicates the scalability of the system energy with changing conditions and quality requirements. A novel technique, Signal Bypassing and Zero Insertion, to design energy-aware multiplier in multi-rail encoding logic is developed. The results show that multi-rail energy-aware designs have advantages not only in energy saving, but also in delay reduction.
Wu et al developed model-based and regression-based colorimeters in their paper entitled Imaging colorimetry using a digital camera. They found that the regression-based system worked better than the model-based syste...
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Wu et al developed model-based and regression-based colorimeters in their paper entitled Imaging colorimetry using a digital camera. They found that the regression-based system worked better than the model-based system. In this work, we modify their regression-based model slightly to improve the system performance. We also present another regression-based model that is capable of recovering the spectral reflectance of teeth. Both models are realized and evaluated clinically.
During flight, aircraft avionics transmit and receive RF signals to/from antennas over coaxial cables. As the density and complexity of onboard avionics increases, the elec.romagnetic interference (EMI) environment de...
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During flight, aircraft avionics transmit and receive RF signals to/from antennas over coaxial cables. As the density and complexity of onboard avionics increases, the elec.romagnetic interference (EMI) environment degrades proportionately, leading to decreasing signal-to-noise ratios (SNRs) and potential safety concerns. The coaxial cables are inherently lossy, limiting the RF signal bandwidth while adding considerable weight. To overcome these limitations, we have investigated a fiber optic communications link for aircraft that utilizes wavelength division multiplexing (WDM) to support the simultaneous transmission of multiple signals (including RF) over a single optical fiber. Optical fiber has many advantages over coaxial cable, particularly lower loss, greater bandwidth, and immunity to EMI. In this paper, we demonstrate that WDM can be successfully used to transmit multiple RF signals over a single optical fiber with no appreciable signal degradation. We investigate the transmission of FM and AM analog modulated signals, as well as FSK digital modulated signals, over a fiber optic link (FOL) employing WDM. We present measurements of power loss, delay, SNR, carrier-to-noise ratio (CNR), total harmonic distortion (THD), and bit error rate (BER). Our experimental results indicate that WDM is a fiber optic technology suitable for avionics applications.
This paper proposes a state of the art control system for a service robot based on the service/client architecture of Jini over an open network. Jini based on Java runnable on multi-platform is the middleware technolo...
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This paper proposes a state of the art control system for a service robot based on the service/client architecture of Jini over an open network. Jini based on Java runnable on multi-platform is the middleware technology which is designed for network plug-and-play, no hardware/software distinction, spontaneous networking and simple connecting procedure. This paper shows the architecture of the Java-runnable embedded system and resource sharing technique based on the Jini technology. Basically the proposed system is open to various client devices such as PC, PDA(Personal Digital Assistance) and possibly information appliances, differently from the conventional remote control systems which use only PC as its client environment to access the robot service. The target robot is teleoperable via the standard point-and-click mouse commands over the World Wide Web. Some experimental results show the efficiency of the proposed near on-line control system which is designed according to the proposed procedure in this paper.
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