At Prairie View A&M University, we developed a new Mixed Signal systems and Broadband Access Technology Laboratories over the last few years. These laboratories are used in helping our premier Semiconductor and Te...
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At Prairie View A&M University, we developed a new Mixed Signal systems and Broadband Access Technology Laboratories over the last few years. These laboratories are used in helping our premier Semiconductor and Telecommunication companies in their various areas of research needs, such as, mixed signal design, testing and in interoperability and reliability studies. These laboratories are used also for the training of our students in these emerging areas of technology and for research, especially, the Digital Subscriber Line (DSL) broadband mixed signal technology. As the paper will demonstrate, we introduce our students to the modeling and simulation of an 8-Pulse Amplitude Modulation (PAM) transceiver that can be fabricated using the Complimentary Metal Oxide Semiconductor (CMOS) transceiver technology. The transmitter incorporates a pattern generator and a pseudorandom bit sequence (PRBS) generator, which are multiplexed to a 3-bit digital-to-analog converter (DAC) with pre-emphasis. The receiver integrates three 3-bit analog-to-digital converters (ADCs) for over sampling of the transmitted data. The modeling and simulation design was implemented using Matlab/ Simulink platform. This modeling and simulation design is developed and implemented using an 8-PAM system, which partitions the data from the transmitter into 3-bit, 8-level quantized form. This type of multi-signaling reduces the symbol rate and thus limits data error in the receiver. To boost the efficiency and reliability of the system, three ADCs are used, instead of one, sampling three times the channel data rate. In this design, a special data select code is written with Matlab/Simulink platform to recover the transmitted data. The data from the transmitter is recovered by error correction technique using the Matlab code. As part of our goal in the Electrical engineering and engineering Technology Departments to expose our students to hands-on training, the students are given the opportunity to model,
In a petroleum refining plant, the high-pressure gas leaks resulting from equipment failures may lead to disasters. To minimize these disasters, technology for the early detection of leak sound is indispensable. We ha...
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In a petroleum refining plant, the high-pressure gas leaks resulting from equipment failures may lead to disasters. To minimize these disasters, technology for the early detection of leak sound is indispensable. We have employed chaos theory to identify these dominant sounds, and have already reported these results in papers listed in reference. However, the leak sound is not always more regular than the background noise depending on equipments or weather conditions. In order to detect the high-pressure gas leak sound, it is necessary to estimate the steady state range quantitatively using chaos theory from the background noise. Based on the concept, we describe chaos information criteria for the leak sound detection algorithm. Applying the chaos information criteria to characterize the measured sound data, we conducted the leak sound detection experiment by leaking steam artificially using a silencer nozzle near the high-pressure gas unit in Idemitsu Kosan Chiba Refinery
A modeling framework (Wetland-DNDC) that describes forested wetland ecosystem processes has been developed and validated with data from North America and Europe. The model simulates forest photosynthesis, respiration,...
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ISBN:
(纸本)1892769530
A modeling framework (Wetland-DNDC) that describes forested wetland ecosystem processes has been developed and validated with data from North America and Europe. The model simulates forest photosynthesis, respiration, carbon allocation, and litter production, soil organic matter (SOM) turnover, trace gas emissions, and N leaching. Inputs required by Wetland-DNDC include daily meteorological data, forest type and age, soil properties (e.g., texture, initial SOM content, bulk density and pH), and forest management practices (e.g., harvest, thinning, fire, reforestation, drainage, wetland restoration etc.). For wetland applications, observed or modeled water table depth data are required to drive the soil redox potential dynamics. Wetland-DNDC runs at a daily time step, and produces daily and annual results of forest growth, net ecosystem C exchange, fluxes of CO2, CH4, N2O, NO, N2, and NH3 emissions, and N leaching from the rooting zone. This study extended the original field-scale model to simulate the carbon, nitrogen, and water dynamics at the landscape scale by linking the biogeochemical processes to groundwater table dynamics predicted by the spatially explicit MIKE SHE hydrological model. Model testing and validation was performed with both hydrological data and carbon flux data from a 40 ha cypress wetland - slash pine flatwoods watershed (40 ha) in north central Florida. We found that pine plantations sequestered 167 tons C/year and cypress wetlands are weak carbon sources (i.e. 8 tons C/year) during averaged climatic conditions. However, a drought could turn the flatwoods system from a strong carbon sink to a carbon source. Pine uplands were sources of N2O emission at the landscape scale (41 kg N2O /year), and wetlands are sources of CH4 emission (i.e. 2.5 tons CH2/year). Wetlands reduced large amount of nitrites by denitrification, but nitrogen leaching into surface water is also common.
In this paper, new attitude determination algorithms using pseudolite signal phase measurements are developed and presented with realistic simulations. Pseudolite signals are used to replace GPS signals which are ofte...
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In this paper, new attitude determination algorithms using pseudolite signal phase measurements are developed and presented with realistic simulations. Pseudolite signals are used to replace GPS signals which are often not available due to blocking by nearby large structures, for example, a crew return vehicle under the International Space Station. A new observation model needs to be applied because spherical wavefronts are present for pseudolite signals, which are much closer to the antennas than GPS signals. Both static and filtering methods are developed. An iterative algorithm using the Levenberg-Marquardt method and a nonlinear Predictive filter provide a deterministic solution;however, they are not suitable for moving cases. Instead, the nonlinear Predictive filter, the extended Kalman filter and the Unscented filter using angular velocity measurements as well as pseudolite signal phase measurements are developed. In the convergence comparison, the Unscented filter and the Predictive filter show more robust behavior than that of the extended Kalman filter.
We demonstrate, for the first time, micromechanical detection of the neurotransmitter dopamine and its discrimination from ascorbic acid. Microcantilever sensors were fabricated and coated with the polysaccharide chit...
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This paper is concerned with a new approach for sensor data processing for sensor networks in which multiple sensors are supposed to monitor overlapping part of the environment. The proposed method is based on collect...
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This paper is concerned with a new approach for sensor data processing for sensor networks in which multiple sensors are supposed to monitor overlapping part of the environment. The proposed method is based on collective synchronization of nonlinear coupled virtual oscillators whose natural frequencies are set to sensor data. Under appropriate conditions, the oscillators are locked to a common frequency. This convergent behavior is interpreted as data processing for bleaching and classification of noisy sensor data.
In this paper, a low voltage current conveyor (CCII) based multifunction filter is presented. Firstly, thanks to an optimizing heuristic, an optimal sizing of a low voltage low power CMOS current conveyor (CCII) was d...
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In this paper, a low voltage current conveyor (CCII) based multifunction filter is presented. Firstly, thanks to an optimizing heuristic, an optimal sizing of a low voltage low power CMOS current conveyor (CCII) was done. Hence, we improve static and dynamic performances of this configuration. The optimized CCII configuration has a current bandwidth of 1.103GHz and a voltage bandwidth of 1.18GHz and 33.4Ω as RX parasitic resistance value. Secondly, implementation of a multifunction filter based on this configuration was done. The current mode filter has a tunable central frequency in the range [50MHz-800MHz]. PSPICE simulations are presented to demonstrate these results.
This paper proposes a new high-speed reclosing operation method to improve the stability in power system with the fault current limiter. From an angular velocity, a field system voltage and a phase of the generator, t...
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ISBN:
(纸本)0889865868
This paper proposes a new high-speed reclosing operation method to improve the stability in power system with the fault current limiter. From an angular velocity, a field system voltage and a phase of the generator, the proposed operation method calculates the optimum reclosing time domain. The fault current limiter is used the reactance type or the resistive type. The examination was carried out using the Inst. of Electrical Engineers of Japan one-machine infinite bus system model in order to demonstrate the effectiveness of the proposed method. The Impact Ver2.3 was used in the computer simulation.
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