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This work presents unique circuit design techniques for on-chip passive devices implemented in low-cost bulk CMOS technology. As the full potential of active devices for silicon-based millimetre-wave circuit design has been pushed almost to the limit, it is important to find an alternative way to further improve the performance of circuits/systems operating at millimetre-wave frequency regions. This is known as passive-inspired design methodology. Two devices, namely a reflection-less bandstop filter (BSF) and a single-pole doublethrow (SPDT) switch, are used as examples to demonstrate the proposed novel design methodologies.

In this work, the design of a wideband millimetre-wave (mm-Wave) power amplifier (PA) is presented. To ensure the designed PA has not only a sufficient output power with good power-added efficiency (PAE) but also superior input and output impedance matching, a balanced amplifier (BA) architecture is used. A prototype PA is designed in a 0.13-µm SiGe HBT technology. With a 1.6- V power supply, the PA can deliver more than 15 dBm saturated output power between 85–100 GHz that is equivalent to more than 16% fractional bandwidth. The peak PAE is better than 14.7% within this frequency range. The overall physical dimension of the designed PA is very compact. Including all pads, it is only 0.6 mm x 0.9 mm.

Considering the complexity of the supercapacitors model structure and the accuracy of the external feature description, the dynamic model is established as the equivalent model of the supercapacitors. The model reduces inductance on the basis of the dynamic model and determines the number of RC (Rwsistor-Capacotance) networks. Aiming at the parameter identification process, the EKF (Extended Kalman Filter) algorithm is proposed to replace the EIS (Electrochemical Impedance Spectroscopy) method, and the algorithm is simulated and experimentally verified. The simulation and experimental results show that under UDDS (Urban Dynamometer Driving Schedule) conditions, the simulated voltage value of the supercapacitors model can follow the measured voltage value well, and the error is small. The average relative error of the supercapacitors model under UDDS conditions is less than 2.14%, which verifies the accuracy and effectiveness of the proposed model and algorithm.

A powerful tool to process and analyze Nuclear Magnetic Resonance (NMR) signals is inversion, of which essence is to solve the Fredholm integral equation of the first kind with non-negative constraints known as an ill-conditioned problem. In this paper, an inversion method is presented based on the regularization method. The proposed objective function can turn the minimization regularization with non-negative constrains into unconstrained maximization, which is piecewise, quadratic and differentiable. The Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm is applied to deal with the inversion problem, and an automatic method is demonstrated to pick up regularization parameter by combining the L-curve method with generalized cross validation (GCV) method. Compared with other methods, the proposed method is capable of inversing both ID and 2D NMR signals data and obtaining reliable NMR spectrum even in the case of a low SNR. The numerical simulations and practical experiments prove the accuracy and efficiency of the inversion method.

The technology of laser-driven flyer can be applied in research fields such as explosives initiation. Flyer velocity is an important indicator to measure the impact initiation ability of laser-driven flyer. A one-dimensional numerical simulation model of laser-driven flyer is established. The phase transition of the aluminum film, the laser energy absorbed by plasma, the dynamic mechanical response inside the flyer and the interaction between the flyer and air are considered. The plasma-driven flyer process are simulated by using the weighted essentially non-oscillatory (WENO) finite difference scheme, level set equation and ghost fluid method. It is found that at the end of laser irradiation, the aluminum film exhibits three regions: gas phase, gas-solid mixture phase and solid phase. High pressure plasma forms the gas phase region, and its width represents the ablation depth of aluminum film. The solid phase region forms a flyer under the action of the plasma. During the acceleration process, the flyer undergoes intense compression and tension. The flyer velocity can lie improved by using double-pulse laser.

This paper is mainly about the design of the security system for supermarket mainly including the upper computer part and the lower. The lower computer is the hardware design and software design of MCU and PLC. And the upper computer is mainly the design of configuration interface and configuration program design. The hardware circuit design adopts STC89C52 as the main control module to regulate flame sensor module, gas sensor module, infrared sensor module and serial port module. PLC uses FX-2N series as the actuator to realize the sound-light alarm and the directional light for personnel evacuation. At the same time, KingView is used as a real-time display of collected data and data circulation tool between MCU and PLC. Software design and debugging is a necessary way to realize the system. The design of supermarket security system is mainly used to timely alarm when the fire and gas leakage occur in the warehouse, counter, kitchen and other places of the supermarket, in order to reduce financial loss and personal injury.

This paper uses a simple two-wheel self-balancing car as the design platform., the gesture sensing system with MPU6050 serves as the main sensor. The data of two sensors are filtered and fused by discrete Kalman Filter. ARDUINO is a nuclear control processor to complete the processes of data collection, analysis, processing and body control. PID control algorithm is adopted to realize two wheels which are self-balancing and use mobile APP to connect with Bluetooth in order to send commands to control the car's movement. The experimental results show that the performance of the system meets requirements of this design.

This paper mainly completes the hardware platform and software design of the wireless car control system. Hardware platform design using modular design ideas, at the same time, using ARDUINO UNO R3 module as the main control part, ultrasonic sensor module, Bluetooth module, bee sound alarm module, motor driver module as the main modules; software development and design uses ARDUINO programming to write the main program, realizing the car Bluetooth wireless control and automatic ultrasonic obstacle avoidance. And it also uses top-down design ideas. Buzzer alarm module is aim to achieve the automatic obstacle avoidance when the obstacles are close to the car. Ultrasonic distance measurement module HC_SR04 is aim to measure the distance of obstacles and the car, and then to achieve the perception of obstacles. The Bluetooth module HC_05 is used to realize the communication between the control terminal and the control center. Motor drive module L298N for the motor drive is the driving force for the car parts.

This article presents a solution for an elderly health care wristband based on the MCU, which integrates electronic information technology, vital signs monitoring, communication networks and other technologies as a whole, the temperature sensor, pulse sensor and vibrator as the object of study to MCU as the core to form a complete system with signal acquisition, data processing, data communications, intelligent protection and other functions. This article begins with the introduction of the overall system design ideas, the focus of detailed analysis of the entire system hardware and software design in two aspects. In the aspect of hardware, using STC90C58RD + as the controller, the design of the hardware system is simplified. The whole hardware system circuit consists of five parts: MCU minimum system., DS18B20 temperature measurement module. pulse monitoring module, vibrator module and GSM communication module. In terms of software, KeilVision4 is used to write the main program, and the signal measurement and monitoring are realized by using modular and top-down design ideas. The design of each part of the application is explained in detail. At the end of the dissertation, we make a brief introduction and full-text summary of the hardware and software debugging of the whole system.

This case study preliminarily collected 60 Nordic Musculoskeletal Questionnaire (NMQ) data of workers from handmade drinks stores to understand their discomforts on various body sites. The NMQ results indicate that the overall prevalence of musculoskel-etal disorders was 88.0% within 1-year. In terms of discomfort, 66.4% of the respondents experienced discomfort at hands/wrists, followed by lower back/waist (41.5%), knees (38.2%), and shoulders (36.5%). The discomfort level of hands/wrists was significantly affected by the gender (female) and the weekly work days (> 5 days). The impact on the knees was the age (≤ 22 yrs) and the rest time arrangement (no), and the impact on the shoulders included the job tenure (> 2 yrs), the daily work hours (> 6 hrs), and the daily shaking cups (> 100 cups). The findings of this study can be served as references for the prevention from the musculoskeletal disorders resulting from the drinks handmade task.

Complex mechanical parts have characteristics of irregularity and certain statistical self-similarity, which can be described by fractal dimension. And the values of their fractal dimension can be used as an measurement to classify and recognize the mechanical parts. In addition, the values can guide robots to grab parts. However, the image obtained by a vision system, which contains part images main image and image background will affect the calculation of fractal dimension of main images. In order to solve the problem, an improved differential box-counting method is designed in this paper. The fractal dimension of part images which has been cut and rotated can be calculated using this differential box- counting method. The experimental result shows that the improved differential box-counting method can calculate the fractal dimension of different size-length images, and the values are more stable. The improved method solves the problem that traditional algorithm can only calculate the fractal dimension of image which side length is integer power of 2.

The fractal dimension, an important parameter as a measure of roughness of image, has been widely utilized to image classification, recognition and segmentation etc. Differential box-counting approach is widely applied to estimate fractal dimension in the calculation approaches of fractal dimension. However, this approach can not accurately calculate fractal dimension of image which have smaller gray level. In response to the issue, this paper proposes an improved differential box-counting method on the height h' of box. In order to verify the superiority of the improved algorithm, DBC, RDBC, SDBC and improved DBC are separately utilized to estimate fractal dimensions of random images with different gray levels and texture image with different sizes, and then to compare. Experimental results demonstrate that: improved differential box-counting approach is more stable for random images with different gray levels.

HT-350 is a novel product to do process temperature in-situ measurement. Temperature is the most important factor in strip process. In this paper, HT-350 data helps customer a lot in process maintenances and recipe tuning. The final goal is process monitor and control fab off-line etching rate (ER) chart by HT-350 wafer.

A vector signal can be sparsely represented by a linear combination of small number of atoms in a dictionary. Many works focused on finding this dictionary by adopting a learning point-of-view. We present a new dictionary learning method with Weighted Stochastic Gradient Descent (WSGD). We construct a novel cost function by introducing a weighting matrix and solve this problem by stochastic gradient descent. It is demonstrated from synthetic experiments that our method have a good performance in signal representation capability and the ability to recover the original dictionary.

Model validation is a highly recommended practice that should be performed periodically since the system model is very important for ensuring reliable and economic power system operation. Currently, field data are used to validate a specific model or an entire system. An FNET-based model validation procedure is proposed in this paper. It uses wide-area measurements to correct the response found from simulations so that the simulation output is close to the measurement of system events. An example case is given which demonstrates the successful application of this method. Some general rules are also concluded for system-wide model validation based on FNET measurements.

A fast islanding detection tool can help power dispatchers monitor and control power system operations. Frequency monitoring network (FNET) is a low cost and quickly deployable wide-area phasor measurement system at the distribution level. The frequency disturbance recorder (FDR) in FNET is actually a single-phase phasor measurement unit (PMU) in the sense that it measures the voltage phase angle, amplitude, and frequency from a single-phase voltage source. Based on the data collected by the FDRs deployed in the North American power grid, two islanding detection methods, the frequency difference method and the change of angle difference method, are proposed. The six cases, including islanding cases, a generation trip case and a load shedding case, are presented to verify the proposed methods of islanding detection. The results show that the proposed methods can correctly detect power system islanding, and will not be falsely triggered by generation trips and load shedding.

Nation-wide, or largely synchronous activities, such as the World Cup or Super Bowl, have impacts on the power grid frequency response. This paper examines the influence of these sporting events on power system dynamics using data collected from the Frequency Monitoring Network (FNET). The frequency data of the German power grid during the 2010 World Cup semifinal game and the U.S. power system during three consecutive Super Bowls are investigated as examples of societal event impacts on power frequency. The frequency observations and analyses demonstrate such significant effects on the power system. Additionally, featured characteristics are drawn from the frequency data and several special events during the Super Bowl are examined.

Low frequency oscillations in the power grid can be classified into three types associated with power system events, non-obvious disturbances, and normal power system operations. A statistical analysis is introduced for the three types of oscillations in the Eastern Interconnection (EI) between 2009 and 2010 supported by the North American power Frequency Monitoring Network (FNET). Six “Type III” oscillation cases in the EI are investigated and some empirical conclusions are compared with “Type I” oscillations.

This paper discusses how the single phase phasor measurement data are used to validate the Oahu island grid model. The island system model is first established using available literature and proper assumptions. After validation via real system measurements, the physical model can truly represent the system dynamics. The model is used to study the integration of renewable source on the Oahu power grid.

Analysis of power system dynamics helps to understand the operation of a power system. Therefore, it is significant to design and develop advanced visualization tools to interpret frequency, voltage magnitude, and phase angle information so that it can be presented to the operators in an intuitive manner. On the basis of the measurement data collected by widely-distributed frequency disturbance recorders (FDRs), visualization tools have been implemented for the FNET system. A number of FNET visualization tools are discussed in this paper, including real-time visualization, animated event replay, visualization of oscillation mode analysis and visualization of propagation effects in two dimensional systems. These tools correlate the FDR measurements with their corresponding geographical information, and transform the combined matrices into different graphic formats using various computer techniques and programming languages. The graphics generated by these tools facilitate power system operation by allowing an operator to monitor power system dynamics, perform post-event analysis and identify modal oscillations more efficiently.

The inter-area oscillations occurring in the Eastern Interconnection (EI) are investigated by six typical cases using the FNET data. The matrix pencil method of multiple signals is used for the modal analysis. The parameters related to mode shape are calculated. The mode shapes for the dominant mode are revealed for each case. Analysis results depict a view of inter-area mode distribution in the Eastern Interconnection.

Due to the influence of the local noise at the distribution level, the frequency curve obtained from the frequency disturbance recorder (FDR) unit is too non-stationary to observe its wave-front directly, which causes some problems in the event location estimation method. In this paper, a morphological filter (MF) is employed to extract the wave-front arrival time and the trend of the frequency curve. With the help of the MF, the accuracy of the event location method is greatly improved.

TSP is a well-known NP-hard problem. Although many algorithms for solving TSP, such as linear programming, dynamic programming, genetic algorithm, anneal algorithm, and ACO algorithm have been proven to be effective, they are not so suitable for the more complicated large scale TSP. This paper offers a method to decompose the large-scale data into several small-scale data sets by its relativity; and the results of each small-scale data set which represents a small-scale TSP compose the whole result of the large-scale TSP. An adaptive clustering method is presented and a novel genetic algorithm for TSP is described in this paper.

Due to the fast advancement of network technologies, the study of service-oriented architectures (SOA) has attracted much attention recently, taking advantage of the benefits of distributed computing and integration. Web service is a very popular and widely accepted implementation of SOA. The use of Web services holds the advantages of a loosely-coupled system where all components can be developed at independent platforms and be connected with the Web service protocols via the network. However, the tendency for methods of applying Web services over the network is getting more and more complex. Many applications rely on not just one Web service, but a whole school of them. Thus, how to compose and integrate different Web services efficiently to provide complicated network services has become an essential topic in system development and design. This paper proposes a new problem which investigates the possibility of minimizing the number of hops of Web services while trying to finish a set of tasks. It also provides a polynomial-time, optimal Web service integration method using greedy strategy to integrate the Web services in order to complete those tasks. This method can achieve the goal of using the minimum number of hops of Web services over the network.

Meta material has been demonstrated and applied in fabricating novel structures such as super lens, invisible cloaking and perfect absorber. The existence of a meta material layer in a stack consists of positive index material can result in a zero refractive index stack, which is also interesting in both physics and technology points of view. The stacking of negative index material and positive index material, where the impedances of negative index slab and positive index slab are matched, was manipulated so that the favorable outcome will be a zero equivalent index material with equivalent impedance different from zero. The reflection coefficient was zero at 90 degree incident angle, hence no reflection, and the calculated transmission is unity. Simulation demonstrates that there is no phase change and the wave propagates smoothly through the stack and the interfaces between slabs. Another kind of perfect absorber is also proposed by composing the 3-slab structure into the diffraction multi slits. Simulations show there are no back-scattering wave and transmitted wave.

A novel image processing technology, called a high performance filter based on statistic methods for image processing (HPFSM), is proposed in this paper. In the HPFSM system, a high performance image filter is employed for removal of impulse noise based on statistic methods. While detecting noisy pixels, the concept of algorithms is based on the well-known statistic methods, Chebyshevpsilas theorem, and a fuzzy mean process to estimate the dependable interval for each pixel. Subsequently, restoring process for noisy pixels utilizes a novel method by the scope of mean-closure function with a growing window. Experimental results demonstrate that the HPFSM system achieves high performance for image processing and outperforms the existing well-known methods, even if there are many blocks of noisy pixels at the high noise rate of images.