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Solar cells have been a cost-effective technology of producing a sustainable electricity using renewable sun energy. In this paper we have focused our research on an innovative yet simple approach including concentrated PV (Photovoltaic) cells using Fresnel lens. In our findings we tried to expound the refracting properties of the Fresnel lens to concentrate the solar spectrum on to a photovoltaic cell. MATLAB Simulink simulation was used to demonstrate that the intensity of the incident light (photons energy) prominently influences the output power and hence efficiency of a given PV cell. The final conclusion of the paper was helpful in achieving the overall increase in efficiency of a PV cell.

In this paper performance of KNN models are evaluated by changing K-fold cross validation parameter and total number of nearest neighbors while classifying WESAD dataset using sklearn library of python programming language, in order to finalize best possible number of nearest neighbors. Performance of KNN models drastically change when total number of nearest neighbors are modified irrespective of the dataset. Consequently for KNN based machine learning applications, tradeoff between optimum performance and computational cost is achieved by limiting total number of neighbors and hence controlling complexity of the model. Thus less computationally expensive KNN models can be directly implemented on raspberry pi, multicore microcontrollers, and low power IoT devices for classifying sensor data on portable embedded systems.

This paper describes a methodology of creating custom dataset and then using convolution neural network (CNN) model for performing image processing operations on Google’s t-rex game using tensorflow and keras framework. Machine learning professionals depend on online available datasets, specifically for computer vision based algorithms, since deep neural networks require specific input shape, size and channels before starting training process. Unfortunately, google’s t-rex game does not have any directly available dataset unlike various image processing datasets. Therefore in this paper step by step process is provided for creating, training, and testing customized dataset with help of CNN model coded in python programming language for both GPU and CPU architectures.

Current matching in multi-junction solar cells has been an issue that up to now has had few good solutions. It is important to match the current to produce efficient cells. This paper describes theoretical analysis of the partitioning the different junctions to be able to match the current. This is a simple process that will allow triple-junction concentrator cells to gain much higher efficiency. The paper also discusses current matched partitions with different structured heterojunction solar cells.

Proper power sharing among distributed renewable energy generators (DGs) in hybrid AC/DC microgrid is an important prerequisite for the stable system operation. In this paper, a secondary power sharing control strategy is proposed for hybrid microgrid based on a maximum power coordination factor (MPCF). Firstly, the time delay algorithm is presented to help automatically identify the MPCF within each sub-grid. Then the MPCF is employed as a unified reference to be shared with other DGs through communication. Upon this, the bidirectional interlinking converters (BIC) only needs to collect MPCF of each sub-grid to achieve accurate power sharing among the hybrid system regardless of influence from line impedance or other interference. Compared with conventional methods, the power sharing accuracy is improved and the communication burden is greatly relieved. Finally, simulation and experimental tests are conducted to verify effectiveness of the proposed strategy.

Three-phase four-wire virtual synchronous generator (TPFW-VSG) provides a zero-sequence current path by introducing a neutral line. However, it will generate an inrush current under asymmetric faults, which will damage the power electronic devices. Therefore, it is of great value to analyze TPFW-VSG’s fault current characteristics. In this paper, the calculation method of instantaneous inrush current of TPFW-VSG under asymmetric faults is proposed by simplifying equivalent models, and the main influencing factors of asymmetric faults current are analyzed. The analysis shows that the fault current is mainly composed of the periodic component and the free component. Moreover, the main influencing factors include control loop and asymmetric faults type. Finally, PSCAD simulation and MATLAB calculation results verify the correctness of the above analysis.

Synchronverter is subjected to a large inrush current when a short-circuit fault occurs, which may cause serious damage to the inverter and utility grid. Therefore, it is very important to figure out the fault current characteristics of synchronverter, and it is helpful for the study of restraining the fault inrush current. In this paper, an asymmetrical fault current calculation method of synchronverter using the instantaneous symmetrical component method is proposed. It is found that each phase asymmetrical fault current consists of a periodic component and a dc component. Comparisons between calculation and experiment results verify the practical application validity of the proposed calculation method.

A simplified mathematical model for the derivation of a non-ideal two-diode PV cell is presented in this paper. The authenticity of the derived model is seen via the 14% efficiency calculation garnered at the end of the Simulink simulation. While many models were mathematically derived and incorporated into the final model, these were not displayed due to space restrictions. Upon finding the optimized parameters, the researcher can then design a far more efficient and cost-effective PV cell.

Response model is one of the most frequently used predictive model. So I make a comprehensive introduction about basic concepts, key functions and main contents of response model and evaluated the model. Through design for utility function and attribute weights to get market value function. In this progress, positive cases and negative cases must be considered. Calculating market value can help enterprises to sort the customers.

The Smart Home is based on the Wireless Sensor Network (WSN) and Embedded System (ES). The most important parts of the Smart Home are low-power and high-security. And it is very vulnerable to various attacks ether an active or passive one in WSN. We shed light upon some existing security flaws in W2 and ZigBee. Some are quite useful to defend the various attacks, but don't suit for the Smart Home. We propose that a new balanced security WZ-lcp protocol which can achieve our requirements. First, in every facility we store two int which can be used as the keys for the authentication, and also can be changed with the time. Second, we do time synchronization to update keys. Finally the proposed scheme achieves balanced and security without costing power-wasting and data collision.

The paper describes the design of a capacitor-free phased locked loop realized using 45 nm technology. Phase locked loops (PLL) find widespread application in electronic circuits, especially in generating high speed clocks for digital chips. Traditional analog PLL designs use capacitors and resistors in the charge pump and the filter circuits. These components occupy large area, adding to the circuit cost; in addition to consuming more power. These limitations can be removed by building a completely digital PLL. But fully digital PLLs have their own drawbacks, especially inaccuracies due to the quantization errors, coarser-grain control of the output frequency generation and errors at higher frequencies. As a result, completely digital PLLs are not suited for generating high frequency signals. In this paper, we present the design of a capacitor-free PLL. It retains the analog Voltage Controlled Oscillator (VCO) in order to run accurately at high frequencies, but replaces all other analog components with their digital counterparts. Incorporation of the digital components eliminates the capacitors and resistors in the circuit and reduces the circuit area and power consumption, while also making the design independent of thermal noise, aging, mismatch and leakage due to the charge pump.

In this paper; Chinese University of existing physical education model analyzes the construction with Chinese universities as the center of leisure sport “club” type of recreational sport education model. Research shows that education is an adaptive recreational sports leisure times through body movement, seeking to set individual mental and physical development of competitive, exhibition, entertainment and educational activities for the whole of modern education. In recreational sports as the center of the “Club” model PE teaching, it is focusing on student life of leisure sports sense and the student movement habits, taking into account the student's interest and expertise, which is an ideal mode of Physical Education.

Energy is a limited resource in wireless sensors networks. One kind of digital wireless gas node with low power consumption is designed and implemented, the main point of energy saving technology is advanced and the design of each model is given in details. With analysis and computation of the energy consumption of real gas node, the following conclusion is made: the gas node with low power consumption can normally work for 3 to 5 years, and it is suitable for the gas automatic reading system.

This paper presents the design and implementation of a 6 Gbps clock and data recovery (CDR) system for Serial Advanced Technology Attachment (SATA) standard. The CDR incorporates half rate phase detector and is realized using a 2 loop PLL consisting of a coarse loop and a fine loop. Fast frequency acquisition is acquired through coarse loop and fine phase alignment is performed through a half rate fine loop. While the coarse loop can recover clock ranging from 2.5 GHz to 3.2 GHz the fine loop has an acquisition range of 200 KHz. The design has been implemented in IBM 0.13um CMOS technology. Verilog AMS and Matlab were used for front end design and Cadence for schematic and layout implementation. The overall silicon area of the CDR is approximately 108 X 244 um2 excluding loop filter capacitors.

The combination of ANSYS and ADAMS can improve the precision of system simulation. In this paper, first, a cable-stayed space truss, consisting of stay cables, columns, and the space truss, is built in ANSYS. Second, the modal neutral file (mnf) needed in ADAMS is generated by executing the macro command “ADAMS” and then imported into ADAMS software. Third, the flexible body in the mnf file is connected to the rigid body built in ADAMS through the external nodes specified in ANSYS, and then the dynamic analysis can be carried out. Subsequently, the load file needed by ANSYS could be obtained by clicking on the menu “File Export”. Finally, the load file is imported into ANSYS software by the APDL language and the static analyses corresponding to different load steps are carried out. The simulation analysis shows a good performance and some results we are interested in are obtained.

We present an innovative high efficiency, low cost solar system that can be easily adapted for commercial applications. The solar system separates the wavelengths and concentrates the different wavelengths using one inexpensive Fresnel lens. This allows the specific solar cells to have concentrated light for a specific region of the spectrum which allows for the solar cell to be optimized for that region of the spectrum.

The mathematic model of a two-bar truss is built in MATLAB and the analysis is carried out by the genetic algorithm toolbox. In order to compare with each other, the parametric model of the planar truss is also established by the ANSYS Parametric Design Language and solutions are obtained using the first-order method native to ANSYS. The comparison of the results shows that genetic algorithms do not always display better properties than other algorithms for some problems. Finally, a joint optimization method which combines MATLAB genetic algorithm toolbox and the numerical algorithm based on the quasi-Newton method is proposed. Then the method is identified through the numerical example of the two-bar truss. The simulation results indicate that the joint optimization method can always converge to the global optimal solution.

A phase lock loop is a closed-loop system that causes one system to track with another. More precisely, a PLL can be perceived as a circuit synchronizing an output signal with a reference or input signal in frequency as well as phase. High-performance phase lock loops are widely used within a digital system for clock generation, timing recovery, and to efficiently sequence operations and synchronize between function units and ICs As the digital system grows the role of phase lock loop increases. Achieving low jitter and phase noise in phase lock loop with less area and power consumption is challenging. The present research relates to characterization and redesign of individual blocks of Phase lock loop (PLL) to improve its characteristics. More specifically redesigning of individual blocks like: Phase Frequency Detector to reduce area and static phase error, Voltage to Current converter to linearly increase the current input to the current controlled oscillator, Current Controlled Oscillator to reduce phase noise, amplitude distortion, area and power consumption. We also introduce an additional feedback loop to increase the gain of the charge pump in a manner that linearizes the overall loop gain over wide bandwidth. The Results are substantial improvements in the PLL characteristics such as low jitter, phase noise, area and power consumption.

Because of the deficiency existing in both zero-order algorithm and first-order algorithm of ANSYS, this paper presents an improved method combining with both algorithms. Firstly, the zero-order algorithm is adopted to confirm the approximate location of the optimal solution, which will not be trapped into local optimum solutions. Secondly, the first-order algorithm is applied to determine the best solution by executing restart of optimization design. Finally, the improved method is examined through a numerical example by virtue of ANSYS10.0 and MATLAB7.0. The simulation results indicate that this method is more effective than traditional methods and advantages of it are much more remarkable when it is applied to complicated engineering structures.

We propose a parallel MAX-MIN Ant System (MMAS) algorithm that is suitable for an implementation on graphics processing units (GPUs). Multi ant colonies with respective parameter settings are whole offloaded to the GPU in parallel. We have implemented this GPU-based MMAS on the GPU with compute unified device architecture (CUDA). Some performance optimization means for kernel program of GPU are introduced. Experimental results that are based on simulations for the traveling salesperson problem are presented to evaluate the proposed techniques.

LBS provide users with highly personalised information accessible by means of a variety of mobile devices that are able to locate themselves. Nevertheless, the wide deployment of LBS can jeopardise the privacy of their users, so ensuring user privacy is paramount to the success of those services. This article focuses on finding a new safe and efficient scheme to prevent LBS server or other users in group from receive real user's personal info. In this scheme, we adopt ASGKA protocol to build safe group and design a cycle-like structure to make group member have safe status.

Anatomical imaging modalities such as MR and CT produce high resolution images that are essential in modern health care. Anatomical imaging, however, can be supplemented with functional imaging to provide additional insights into the status and progression of disease. In perfusion imaging, a bolus of contrast entering a tissue region of interest is carefully monitored in order to derive hemodynamic parameters. While useful, perfusion parameter maps tend to be noisy, in part because the parameters of every voxel are computed independently of its neighboring voxels. A spatio-temporally correlated approach to estimating perfusion parameters has been previously introduced. In this paper, we expand upon this earlier formulation and demonstrate its functionality on a set of rectal tumor patients undergoing CT perfusion (CTp) studies. Our results show that our spatio-temporal deconvolution approach is less noisy than conventional singular value deconvolution approach, and show greater separation between normal and cancerous regions.

Hyper transport is a bidirectional, serial/parallel high bandwidth, low latency, point-to-point interface architecture. In this architecture, data can be sent on both rising and falling edges of the clock making it an interface that can transmit the data faster when compared to the other architectures that are available in the market today. This architecture also is ACPI (Advanced Configuration and Power Interface) compliant and can provide low power by switching off when there is no activity in the system. This project is aimed to develop a power managed Hyper Transport system prototype for the transmission of High Definition video. Power is managed by switching the system from active state to sleep state when there is no heavy isochronous data flowing and switching it back to the active state before isochronous data arrives, while by-passing the prioritized video data and interrupts. This project is implemented in Verilog and is simulated using ModelSim. From the simulations, it can be observed that at 50%?70% of isochronous data transfer an overall power saving of 20% ? 40% is achieved.

Considerable attentions have been devoted recently to active vibration control using intelligent materials as sensors/actuators. This paper presents results on active control schemes for vibration suppression of flexible cantilever beam with bonded piezoelectric sensors and actuators. State equations which the generalized modal coordinates as variables are built.With the piezoelectric elements are surface-bonded near the same position to the fixed end of flexible cantilever beam, two active vibration control methods such as Linear Quadratic Gauss (LQG) optimal control and robust H∞ control are investigated. Finally, the simulation results are given to demonstrate the effectiveness of the control method in this paper, compared with the LQG control method, robust H control has strong robustness to modal parameters variation, and it has a good closed-loop dynamic performance, can suppress the vibration better at the circumstance of the system with uncertainty factors.

Piezoelectric materials are finding increasing applications in active vibration control of structures. A widely used modeling technique for piezoelectric flexible structures is the assumed modes method which results in an infinite dimensional model of the composite structure. The paper builds the model of piezoelectric flexible structures and calculates the modal frequency by the application of ANSYS software, extracts the required modes according to the method of model reduction based on the spatial H2 norms of modes. The optimal location of the piezoelectric patches is ascertained by applying the D-optimal design principle, which avoids the locationpsilas randomicity as well as reduces the number of sensors/actuators in terms of not affect the controlling effect. Finally, the paper takes a piezoelectric cantilever beam as an example and gives the step response curve of the system. The results show that this method has more superiority than the ordinary modes truncation.

This paper demonstrates an active vibration control system of flexible structures by using piezoelectric sensors and actuators. A set of vibration control equations, sensing equations and actuating equations are derived through using the modal theory for piezoelectric flexible structures, then the model is converted into the state space form. With recent developments in sensors/actuators technologies, many researchers have concentrated on control methods for suppressing vibration of the structures using smart materials such as piezoelectric transducers (PZT). In this paper, two piezoelectric patches are collocated on both sides of the same position of the structure which used as modal sensors and actuators, and the optimal location of them is ascertained by the function of displacement deflection, a LQR controller is designed based on the independent mode space control techniques to suppress the vibration of the system. Finally, the paper takes a piezoelectric cantilever beam as an example, and gives the control simulation results which demonstrate the effectiveness of the method in this paper.

Based on the linear quadratic Gauss (LQG) optimal control method, the paper introduces an effective procedure to suppress the vibration of flexible structures with the sensors/actuators are symmetrically collocated on both sides of the same position on the host structure. The model of a piezoelectric intelligent cantilever beam is built by the application of ANSYS software. The D-optimal design principle is adopted which is an optimal method which chosen by the maximum determinant of Fisher information matrix as the criteria function. Studies on the modes shapes and dynamic characteristics of the structure, and converts the selected modes into a unitary form by a simple method, the optimal position of the piezoelectric elements can be confirmed by the mode shapes of the structures. Finally, the paper takes a piezoelectric cantilever beam as an example and gives the step response of the system, the results show the effectiveness of this method.

This paper presents the design of low power, low cost design of temperature sensor that has been designed keeping in view VLSI circuits and technology changes. The circuit occupies an area close to 0.01 mm , which is less than 1/100th of the area occupied by most of the previous circuits that use capacitors and A/D converters. Power dissipation of the circuit ranges from 800 muW to 1.2 mW for temperatures ranging between -20degC to 80degC. It has been implemented using TSMC 0.18 mum technology.

State of art phase locked loop (PLL) design methodologies and techniques are always of many mixed-signal circuit designers' interests. In this paper, a fully differential PLL having good common-mode noise rejection (low phase noise) has been designed and demonstrated using TSMC 0.25mum CMOS technology. The design and demonstration included a dead zone eliminating phase frequency detector (PFD) with complimentary signals, a differential charge pump/loop filter (CP-LPF) with common mode feedback, a differential voltage controlled oscillator (VCO) with two stage only differential hysteresis delay cell and a divider. Using the full-custom design flow, each individual building block, like PFD, CP/LPF , VCO and divider has been designed, simulated, extracted (DRC and LVS) and verified (transistor level bottom up verification), then followed by the top level PLL simulation, extraction and verification.

Phase aligned clock multiplier is designed for high performance applications where high-speed clocks are needed including PCs, workstations, and telecom applications. In this paper, a clock multiplier is designed based on the ideology of phase locked loops. It has the following features: operating supply voltage is 1.8 V ; input frequency range is 10-83.33 MHz; output frequency range is 5-166.67 MHz ; input-to-output skew is 200 ps ; 3-multiplier configuration ; output selectable pin phase alignment; single phase locked loop architecture; internal loop filter.

This paper describes an 8-bit, 10 MSamples/second analog to digital converter, with 2V fully differential input range, which is implemented in TSMC 0.25mum CMOS technology. It achieves low power dissipation of 25mW, and the chip area is 0.56mm2. Measured performance yields a very good VTC curve and a sine wave fitting curve for 200KHz input at 10Msample/s, DNL testing of -0.2LSB-0.75LSB; INL testing of -0.2LSB ~ 0.65LSB, 44.62dB of SNDR (signal to noise plus distortion ratio) and ENOB of 7.12 bits

This paper presents the design of a first-order continuous-time sigma-delta modulator. It can accept input signal bandwidth of 10 kHz with oversampling ratio of 250. The modulator operates at 1.8 V supply voltage and uses 0.18 mum CMOS technology. It achieves a level of 60 dB SNR

The goal of this project is to implement a 10-bit segmented current steering TSMC 0.25 /spl mu/m CMOS digital to analog converter. Binary coded 10-bit data is input to the converter. The converter converts all combinations of ten bits from digital form into the corresponding "staircase" voltage levels. A low pass filter placed after the output terminal of the converter is necessary to make the voltage level smooth.

InP surface passivation has been realized by a convenient chemical bath deposition (CBD) of a thin CdS layer. For comparison, samples without any treatments and/or with only a thin SiO2 layer were also prepared. Also studied was the effect of a thin layer of SiO2 deposited immediately after the CdS deposition. Schottky contacts were made on the CdS-passivated InP by electron-beam deposition of Ti/Au. Electrical characterization was conducted by current-voltage (I-V) and current-voltage-temperature (I-V-T) measurements. It was found that the electrical performance of the Schottky contacts of the CdS-passivated InP samples was improved significantly. The thickness (deposition time) of the CdS strongly affects the device electrical performance. The additional SiO2-on-CdS layer plays a key role in the process of InP surface passivation. Post-treatment in the CdS deposition process also strongly affects the surface morphology and electrical properties. Surface morphology studied by atomic force microscopy (AFM) indicates that the surface roughness increased after CdS deposition, though the degree of roughness is reverse proportional to the CdS process time. X-ray photoelectron spectroscopy (XPS) shows that the CdS layer protects the InP substrate during the oxide deposition.