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DNA sequence comparison remains as one of the critical steps in the analysis of phylogenetic relationships between species. In order to get quantitative comparison, we want to devise some mathematical descriptors that would captur the essence of the base composition and distribution of the sequence. In this contribution, we take the DNA sequence double helix into account, and introduce a mathematical...
This paper is concerning the estimation of snow wetness from multi-polarization SAR data. In this paper, microwave interaction with snow covered terrain and different scattering mechanism from snowpack and their backscattering model for developing inversion algorithm with wet snow conditions are described in order to estimate snow wetness. SAR data processing and field measurement of snow parameters...
Ultrasonic sensors are widely used in distance measurement for robots. In practice, there is an important problem about the measurement resolution which is the ability to distinguish different targets. This paper is concern about the range resolution of the ultrasonic distance measurement using cross correlation. The highlight model is introduced to describe the resolution playing an important role...
This paper made use of questionnaire to collect the data and SPSS software to analyze the relationship between pay satisfaction and job performance for employees. Correlation analysis showed that only pay-structure satisfaction had a significantly positive relationship with job performance, while other sub-dimensions of pay satisfaction had no significant relationship with it. Regression analysis...
We present a novel BCH code based sequences design method for generating large families of ranging sequences. The sequences can be used in an OFDMA network to offer sufficient ranging opportunities and guarantee low probability of false detection. Each derived sequence has low peak to average power ratio (PAPR) and cross-correlations with other sequences. These properties enable a mobile receiver...
A distance sensor is presented as a system-on-chip (SOC) solution embedding 2×32 pixels together with an on-chip ring oscillator providing phase-shifted modulation signals for the time-of-flight measurement principle. The low-power pixels consume only 2μA each, manage 150klx of ambient light directly in the circuit domain without using any optical filters, and show characteristic standard deviations...
Exact spread-spectrum code tracking in the presence of multipath is an important issue in distance and time measurement systems. Different tracking algorithms based on feedback, feedforward or a combination of them reduce multipath effects, however, the accuracy of the tracking in presence of short-delay multipath signals is still a problem. In this paper, we consider feedback delay lock loops (DLL)...
In this paper, we present ranging performance results obtained with realistic low-power, low-complexity Low Data Rate (LDR) evaluation platforms, with two Impulse Radio Ultra Wideband (IR-UWB) transceiver prototypes, and one Zigbee platform. The Zigbee platform is based on the TI CC2431 chipset, while the IR-UWB employed by CEA-LETI is mainly based on “1.5-bit” direct sub-sampling at 1Gsps and differential...
A specific issue in the voice password system is addressed in this paper: When the text content of target speaker's enrollment password has been already known by imposters, they can do a well-behaved impersonation using the same text content as the target speaker. This results in a much higher false acceptance than the traditional voice password system. N-gram based nearest neighbor algorithm is proposed...
In this paper, we present a low-complexity Low Data Rate (LDR) Ultra Wideband (UWB) transceiver prototype CMOS chip suitable for a Differential Binary Phase Shift Keying (DBPSK) modulation applied to data transmission with 500 MHz-bandwidth signals. This solution, which is mainly based on “1.5-bit” direct sub-sampling at 1Gsps and differential digital correlations, offers an interesting trade-off...
Today, knowledge of computer technologies has become one of the fundamental skills that everyone should adopt, and formal education is important source of such knowledge. From primary school to university information technologies has been integrated in educational process. We use computers in schools to improve students' knowledge about ICT, and to enhance the educational process. The research has...
Studying the ways to recommend music to a user is a central task within the music information research community. From a content-based point of view, this task can be regarded as obtaining a suitable distance measurement between songs defined on a certain feature space. We propose two such distance measures. First, a low-level measure based on tempo-related aspects, and second, a high-level semantic...
A way of laser ranging was proposed based on autocorrelation property of pseudo-random sequence. The hardware platform of laser ranging was designed and the plan of echo-signal's recognition was given in which the bit width and the period of pseudo-random sequence were detected. The delaying time of the echo signal was also determined according to the auto-correlation properties of pseudo-random sequence...
Ultra-wideband (UWB) communication systems provide very high data rates by transmitting extremely short duration pulses. The impulse waveform is one of the key factors that influence the performance of these systems. While fulfilling the FCC spectral emission requirements, the pulse shape must offer high detection capabilities with suitable levels of accuracy. In this paper, various pulse shapes are...
In this paper we study low-power impulse radio ultra-wideband (IR-UWB) correlation receivers with suboptimal templates, as a promising candidate for a highly accurate wearable human locomotion tracking system. Such a system is theoretically capable of providing a ranging accuracy of 1mm in practical multipath fading channels at a SNR of 18dB. This ranging accuracy is ten times better than the ranging...
A fast and robust method for visual odometry based on the Fourier-Mellin Invariant (FMI) descriptor is presented. It extends previous FMI based approaches in two ways. First, a logarithmic representation of the spectral magnitude of the FMI descriptor is used. Second, a filter on the frequency where the shift is supposed to appear is applied. It is shown with experiments with an Unmanned Aerial Vehicle...
From the concept of Distance and Angle of matrix vector, we lead out the gray image similarity measurements: Distance Measurement and Correlation Measurement. Then the measurement algorithm is extended to color image matching field. The Distance and Correlation between two color pixels are defined and the color image similarity measurement is also defined accordingly. Finally we realize the color...
To improve the localization precision based on RSSI ranging in wireless sensor networks, a localization method based on the ranging-error compensation is presented. By analyzing the tendency of RSSI ranging error with different distance, we propose the mathematical model and the experiment results about ranging-error compensation. It is proved that the method based on ranging-error compensation effectively...
The IEEE 802.15.4a standard for wireless sensor networks is designed for highly accurate ranging with impulse radio Ultra Wideband (UWB) signals. The standard allows a large number of different system parameters for the preamble, which are analyzed in detail for energy detectors. Energy detectors have low complexity and promise low cost and low energy consumption. The focus of this work is on statistical...
A predictive model for estimating the perceived harmony of ordinary multi-colored images is proposed and evaluated. The model is based on earlier research concerning two-color harmonies. Color regions of images are extracted using mean shift segmentation. Global and local harmony scores are derived for two-color combinations included in different subsets of all segmented regions. Statistical measurements...
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