An overview is given of the efficient implementations of CMOS adders and multipliers as well as an investigation on the voltage scaling of glitches in future CMOS process technologies. An extension of the logical-effo...
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An overview is given of the efficient implementations of CMOS adders and multipliers as well as an investigation on the voltage scaling of glitches in future CMOS process technologies. An extension of the logical-effort delay model to include the gate-input to output transition of pass-transistors in complementary pass-transistor logic circuit is also suggested. Three efficient adder implementations are proposed. First, one Manchester adder where repeaters and optimized bypass structure are employed to obtain an area and energy-efficient design. Second, an efficient implementation of the dot-operator cells of parallel-prefix adders, and the third one is rather an accumulator in a special application where it is possible to achieve a lower dissipation at the cost of extra noise.
Estimation of the number of clusters is an essential processing step for various applications. Existing approaches search for an optimal solution by computing and comparing a validity measure for all feasible configur...
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Estimation of the number of clusters is an essential processing step for various applications. Existing approaches search for an optimal solution by computing and comparing a validity measure for all feasible configurations, and tend to under-estimate the number of clusters incorrectly. In this paper, we propose a fast and robust method to estimate the number of clusters without adopting the exhaustive search. Our sch.me first extracts the relationship of neighboring features, and then uses this information to partition the clusters. The superb performance of the method is verified by the simulation results in determining the number of texture segments in the textured images.
This paper proposes an improved ray tracing technique that can reproduce a realistic image based on the spectral characteristic of real lights and objects. The proposed algorithm is able to generate a realistic image ...
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This paper proposes an improved ray tracing technique that can reproduce a realistic image based on the spectral characteristic of real lights and objects. The proposed algorithm is able to generate a realistic image that simulates the physical quantity of light energy incoming toward a viewer. First, an accurate image is reproduced using the backward ray tracing method and by tracing the spectral transformation procedures of the rays using the spectral characteristic of objects and illuminants. Next, the shading model of the reproduction algorithm of a realistic image is improved by applying Bouguer-Beer's law to consider the optical absorptive property of transparent objects. Finally, a new ambient light term that considers the diffuse reflection of neighboring objects is defined instead of a constant ambient light term.
This paper presents the current measurement issues in sensorless control of a permanent magnet (PM) machine based on the fluctuating high frequency voltage signal injection (HFI) method. In such a sensorless control o...
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This paper presents the current measurement issues in sensorless control of a permanent magnet (PM) machine based on the fluctuating high frequency voltage signal injection (HFI) method. In such a sensorless control of the PM machine, the accuracy of the rotor position estimation mainly depends on the accuracy of the current measurement of the drive system. And, the accuracy of current measurement mainly depends on the current scaling errors, offset currents, and the quantization errors of the analog-to-digital (A/D) converter. In this paper, the effects of the current measurement errors on the accuracy of the rotor position estimation in sensorless control of the PM machine based on the HFI method is analyzed using an example of current measurement system and sensorless control sch.me. The simulation and experimental results are shown in order to verify the validity of the analysis results.
In this paper, we propose a modification to DCF (Distributed Coordination Function) to improve the channel utilization in IEEE 802.11 wireless LAN. In the modified DCF, once a station has contended for the channel, it...
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In this paper, we propose a modification to DCF (Distributed Coordination Function) to improve the channel utilization in IEEE 802.11 wireless LAN. In the modified DCF, once a station has contended for the channel, it may transmit multiple data frames continuously to the same destination. We call the process TB (Transmission Burst). The theoretical analysis and the simulation results show that the performance of the modified DCF can be better than that of the standard DCF. In addition, the modification does not introduce any additional control overhead.
An effective compensation method for the IR lamp deterioration in NDIR (non-dispersive infrared) capnograph system is proposed. The optical chamber with two IR (infrared) lamps has been designed newly and an electroni...
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An effective compensation method for the IR lamp deterioration in NDIR (non-dispersive infrared) capnograph system is proposed. The optical chamber with two IR (infrared) lamps has been designed newly and an electronic hardware for the control of lamp intensity has been implemented. After applying the proposed optical chamber and the reference lamp control circuit to the NDIR type capnograph system, it is identified that the proposed method can compensate the lamp deterioration effectively.
In this paper, we propose an efficient resource reservation mechanism called the neighborhood reservation (NR) for ad hoc networks. When a node reserves bandwidth for a QoS flaw, corresponding bandwidth reservation mu...
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In this paper, we propose an efficient resource reservation mechanism called the neighborhood reservation (NR) for ad hoc networks. When a node reserves bandwidth for a QoS flaw, corresponding bandwidth reservation must be done in all its neighborhood nodes simultaneously to eliminate the impact on reserved bandwidth caused by channel contention. Thus the reserved bandwidth for the QoS flow can be guaranteed with certainty. The simulation results show that the effectiveness of QoS reservation can be impravedremarkably by using neighborhood reservation.
The electrical characteristics of biologically active points (BAPs) compared with those of the surrounding human skins are investigated. We confirm that BAPs have lower resistance and higher capacitance than the surro...
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The electrical characteristics of biologically active points (BAPs) compared with those of the surrounding human skins are investigated. We confirm that BAPs have lower resistance and higher capacitance than the surrounding skins have. We find that BAPs have higher characteristic frequency than surrounding skins and sometimes the impedance spectra of BAPs have two semicircles on the complex impedance plane. Therefore, we propose the skin impedance model that is proper to the BAPs. This model describes our experimental results sufficiently.
This paper proposes an algorithm that can reduce the estimation error of surface spectral-reflectance(SR) when using a conventional 3-band RGB camera. In the proposed method, the estimation error is reduced by using a...
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This paper proposes an algorithm that can reduce the estimation error of surface spectral-reflectance(SR) when using a conventional 3-band RGB camera. In the proposed method, the estimation error is reduced by using adaptive principle components(PCs) for each color region. To build an adaptive set of PCs, n SR populations are organized for n PC sets using the Lloyd quantizer design algorithm. The Macbeth ColorChecker is utilized for the initial representative SR values for 1485 Munsell color chips as the total color population, then the Munsell chips are divided into subsets with a set of corresponding adaptive PCs organized for each subset. To evaluate its performance, the proposed estimation method is compared with a conventional 3-band principle component analysis(PCA), 5-band Wiener estimation method, and another conventional 3-band PCA method in estimation experiments for randomly selected SRs from Munsell color chips. The proposed method exhibited a superior estimation performance compared to the two 3-band PCA methods and 5-band Wiener method.
This paper provides a framework for information assurance within collaborative design based on a technique we call role-based viewing. Role-based viewing enables role-based access control through geometric partitionin...
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This paper provides a framework for information assurance within collaborative design based on a technique we call role-based viewing. Role-based viewing enables role-based access control through geometric partitioning of 3D models. The partitioning is used to create variable level-of-detail (LOD) meshes, across both individual parts and assemblies, to provide a model suitable for access rights for individual actors within a collaborative design environment. We show how this technique can be used to implement a hierarchical set of security access privileges based on the Bell-La Padula model. The partitioning is derived from a set of access specifications for an assembly model and its parts. The authors believe that this work is the first of its kind in the field of computer-aided design and collaborative engineering.
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