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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...
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...
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...
In order to study the emission characteristics of the plasma produced by composite metal bridge foil explosion process, the atomic emission spectrometry technique was used to measure the continuous plasma emission spectrum. The composition and ionization of the plasma were analyzed. The plasma temperatures at different delay times after electrical explosion were calculated by the Boltzmann multi-spectral...
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...
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...
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,...
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...
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...
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”...
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.
Career conception is people's basic opinion of careers whose formation is certainly affected by many factors. Through survey and research of career professional ethics, ideals, quality and guidance intention, etc. of students in vocational colleges, we concluded and analyzed internal and external factors affecting formation of career conception of students in vocational schools as well as proposed...
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...
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...
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...
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...
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...
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,...
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