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Wang Y.,Zhejiang Technology Institute of Economy | Baker D.,Indiana University - Purdue University Fort Wayne
Open Electrical and Electronic Engineering Journal | Year: 2014

With the development of mobile Internet and wireless network as well as the rapid increasing number of users, people’s demand for broadband is increasing sharply, making further capacity expansion of the network the major problem for researchers. Wireless Mesh network has the advantages of high network coverage and flexible networking, especially multi-hop wireless network, its important networking format takes full use of the feature of orthogonal channel to raise the throughput of wireless network and utilization efficiency of broadband dramatically and make the channel resources allocation more flexible. This paper points out the advantages and disadvantages of Mesh network by analyzing some relatively classic algorithms based on the research of Mesh network technology in order to increase utilization efficiency of orthogonal channel further. At the same time, it proposes Spatial-Temporal Multi-Channel Allocation Based on the Greedy Algorithm for Wireless Mesh Network which takes the channel allocated in previous slot time into consideration and allocates channels to different ports to reduce the switching time and other costs. Giving the direction of nodes is up stream, it requires well-functioning nodes near the gateway. Any network fault will influence other nodes near these gateways. This allocation realizes the communication between nodes on original channel nodes, increasing utilization efficiency significantly and reducing the burden of parent node. In the end, this paper makes a conclusion of the main work. © Wang and Baker; Licensee Bentham Open.


Chen L.-D.,Zhejiang Technology Institute of Economy | Zhao Y.-R.,Zhejiang University
Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis | Year: 2014

The present study was carried out to detect crankshaft bearing knock using atomic absorption spectrometry (AAS) in an innovative way. Lubricating oil of MAGOTAN 2.0 with mileage of 1000~28000Km and sampling interval of 1000Km changed into atomic vapor in the heat after digesting with microwave. Hollow-cathode lamp made of the same element with metal content under test would radiate characteristic radiation with certain wavelength. A part of atomic vapor was launched with ground state atom after heating with graphite furnace. Concentration-absorbance working curve was finished with standard series sample after absorbance was measured. Finally, element content under test in oil was obtained based on the work curve. Database of primary element (Cu and Pb) content of lubricating oil in the same engine with different mileage was established. Results showed that Cu, Pb content fluctuates with different mileage in a certain range. In practical engineering applications, primary metal content in lubricating oil of engine crankshaft bearing was measured and compared with content variation trend chart. This new method not only helps automobile maintenance personnel to diagnose crankshaft bearing knock under no-disintegration situation but also is benefit for reducing the maintenance cost of automobile greatly and improving diagnostic accuracy of crankshaft bearing knock.


Shao Y.,Zhejiang University | Pan J.,Zhejiang University | Zhang C.,Zhejiang University | Jiang L.,Zhejiang Technology Institute of Economy | He Y.,Zhejiang University
Computers and Electronics in Agriculture | Year: 2014

Carotenoids, which can be part of the food additives and drug additive, are one of important internal quality indexes for living microalgae. In the present study, visible/near infrared (Vis/NIR) transmission spectra in situ of Spirulina sp. suspension were required using an Ocean Optics USB 4000 Spectrometer in the wavelength range of 346-1038. nm, and the loading weights (LW) analysis, uninformative variables elimination (UVE) and successive projections algorithm (SPA) were used to select important variables related to the carotenoids content (CC) for the Spirulina sp. suspension. Different concentrations of 100 samples of Spirulina sp. suspension were selected. The results showed the correlation coefficient (. r), root mean square error (RMSE) and residual predictive deviation (RPD) in the prediction sets were 0.96, 0.23. mg/L, 3.40, 0.89, 0.39. mg/L, 1.59 and 0.96, 0.24. mg/L, 3.44 for x-LW-PLS, UVE-PLS and SPA-PLS model respectively. It indicated that SPA-PLS gave the best result, while x-LW-PLS was better than UVE-PLS. So, Vis/NIR transmission spectra combined with SPA method was feasible to assess CC of Spirulina sp. suspension. And SPA variable selection method can simplify the prediction model and improve the model prediction precision. Furthermore, the method can be used as a good example for the detection in situ of other pigment content in other microalgae. © 2014 Elsevier B.V.


Chen L.,Zhejiang Technology Institute of Economy | Chen L.,Zhejiang University | Zhao Y.,Zhejiang University
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2014

Biodiesel (fatty acid methyl or ethyl esters) is made from vegetable oil or animal fat (triglycerides) reacting with methanol or ethanol using a catalyst (lye). It is safe, biodegradable, and produces less air pollutants than petroleum-based diesel or recycled restaurant greases. With the increasing demand of green energy source and the decreasing of fossil fuel, biodiesel has gained increasing attention as one of the alternative fuels. 100% biodiesel (B100) was used in this study. Experimental samples with water content of 0, 2.50%, 5.00%, 7.50% and 10.0% were set. There were 35 samples for every treatment with different water contents, and total 175 samples. 116 samples were selected for calibration set, and 58 samples for prediction set based with Kennard-Stone (K-S) method. Visible and near infrared spectra (Vis-NIR) technique which was a nondestructive and rapid method, was used to measure the water content in biodiesel. Samples were scanned using the ADS Handheld FieldSpec spectrometer and spectra of samples were acquired. Principal component analysis (PCA) was used to compress spectral data and observe the cluster's situation of biodiesel with different water contents. The scores plot showed a good cluster distribution and the total accumulated variance of PC-1 and PC-2 was up to 99.3%. Random Frog algorithm was applied to extract spectral feature. Then, 8 sensitive wavelengths (563, 560, 642, 565, 562, 493, 559 and 779 nm) were selected respectively. Spectral feature and different water contents were set as input values of partial least squares regression (PLSR) and least squares-support vector machine (LS-SVM) models. It was showed that LS-SVM and PLSR with full spectra had good results, while the variables were too much (116×591) compared with the regression models (116×8). Results of the Random Frog-LS-SVM were better than the Random Frog-PLSR. R of the non-linear LS-SVM models with spectral feature extracted by Random Frog was higher than 0.965, RMSEC of 0.722, RMSEP of 0.520. Sensitive wavelengths extracted were good for eliminating the interfering spectral and improving the accuracy of the model. Results indicated that the Random Frog-LS-SVM as a satisfactory model can measure the water content in biodiesel accurately, which could provide a reference for practical application.


Jiang L.,Zhejiang Technology Institute of Economy | Liu F.,Zhejiang University | He Y.,Zhejiang University
Sensors | Year: 2012

A novel method which is a combination of wavelet packet transform (WPT), uninformative variable elimination by partial least squares (UVE-PLS) and simulated annealing (SA) to extract best variance information among different varieties of lubricants is presented. A total of 180 samples (60 for each variety) were characterized on the basis of visible and short-wave infrared spectroscopy (VIS-SWNIR), and 90 samples (30 for each variety) were randomly selected for the calibration set, whereas, the remaining 90 samples (30 for each variety) were used for the validation set. The spectral data was split into different frequency bands by WPT, and different frequency bands were obtained. SA was employed to look for the best variance band (BVB) among different varieties of lubricants. In order to improve prediction precision further, BVB was processed by UVE-PLS and the optimal cutoff threshold of UVE was found by SA. Finally, five variables were mined, and were set as inputs for a least square-support vector machine (LS-SVM) to build the recognition model. An optimal model with a correlation coefficient (R) of 0.9850 and root mean square error of prediction (RMSEP) of 0.0827 was obtained. The overall results indicated that the method of combining WPT, UVE-PLS and SA was a powerful way to select diagnostic information for discrimination among different varieties of lubricating oil, furthermore, a more parsimonious and efficient LS-SVM model could be obtained. © 2012 by the authors.


Wang X.,China Jiliang University | Wen J.,Zhejiang Technology Institute of Economy
Proceedings - 2010 3rd International Congress on Image and Signal Processing, CISP 2010 | Year: 2010

Recent interests in large displays has led to the rapid development of multi-projector tiled display wall systems, which comprises of an array of individual projectors, and usually driven by a cluster of PCs. Here we design a video players system for playing video streams on tiled display wall systems. The video players system includes two components, server and a set of client players. The server decodes and divides the video streams selected by users, and then broadcasts the video segments to each client players according to their positions. Each client players renders the video segments sent by the server, and deals with geometry calibration and color calibration problems based on preset calibration matrix. Test results show that the above players system can play multiple types of video with high quality and high performance. ©2010 IEEE.


Chen L.D.,Zhejiang Technology Institute of Economy | Zheng Y.J.,Zhejiang Technology Institute of Economy
Advanced Materials Research | Year: 2012

In this paper, graphite oven atomic absorption spectroscopy was adopted to determine typical metals contents, iron (Fe), aluminum (Al), chromium (Cr), in engine lubricating oil for a rapid evaluation about engine wearing conditions. Samples were made into translucent micro-emulsion by adding Tween 80 and 1% nitric acid solution, and then Fe, Al and Cr contents were determined. The recovery rate of standard addition method was achieved as high as 95.3% to 101.1%, and relative standard deviation (RSD) of six times parallel tests were all less than 3%. The results indicated that the adoption of atomic absorption spectroscopy to predict engine wearing condition acquired the following advantages: high sensitivity, simple operation, pinpoint accuracy and excellent reproducibility. © (2012) Trans Tech Publications, Switzerland.


Chen L.D.,Zhejiang Technology Institute of Economy | Shan H.X.,Zhejiang Technology Institute of Economy
Advanced Materials Research | Year: 2012

Through the discussion of main shortages of the high-speed electromagnetic valve used in electronic fuel injection system, the author introduced a new design thought of fuel injector based on 2D technology. Axial displacement of controlling valve was used to control the volume of gushing oil, while radial revolution of spool valve was used to change the time of injection. Additionally, mathematic modeling and MATLAB simulating indicated that, the injector designed based on 2D technology acquired the advantages of quick response and also realized the ideal shape of fuel injection rate. © (2012) Trans Tech Publications, Switzerland.


Han Y.,Zhejiang Technology Institute of Economy
RISTI - Revista Iberica de Sistemas e Tecnologias de Informacao | Year: 2016

Multimedia technology is applied extensively in English teaching. With the development of multimedia technology, the application also becomes a breakthrough. In the higher vocational English teaching, teachers design the course on the premise of paying attention to the multimedia. The application of multimedia technology should also expand the meaning in breadth and depth. The author analyzes the key of multimedia technology based on multimedia English teaching model and utilization of the experiment teaching method. He combines the Matlab software and fuzzy comprehensive evaluation method to verify the significant effect exerted on multimedia technology in English teaching. The studies show that the designed teaching model can effectively serve the higher vocational English teaching.


He Y.,Zhejiang Technology Institute of Economy
Wei sheng yan jiu = Journal of hygiene research | Year: 2010

To establish GC-MS method for the determination of phathalic acid esters (PAEs) in the air of plastic production logistics, and conduct a status quo survey of PAEs pollution in occupational environments basing on it. The determination method was established according to the Monitor Investigating Guidelines on Poisons in Workplace Air, and then used to determine samples collected to carry out an on-the-spot investigation. Calibration curves of the six PAEs were proved to be all linear in the range of 2-1000 ng/ml, equivalent to 0.67-333 microg/m3 in the air considering 3 L air sample was collected. The sensitivities were high with all limits of detection lower than 1 ng/ml, i.e., the minimum detectable concentrations of the six PAEs were all lower than 0.33 microg/m3. Intra-day precision and accuracies were all good, with relative standard deviation in the range of 3.0%-7.8% and recoveries in the range of 93.1%-105.1% respectively. And inter-day precision and accuracies were 3.4%-9.9% and 93.4%-106.4% correspondingly. The eluting efficiency was 92.9%-97.9%, and the sampling efficiencies were nearly 100%. The breakthrough capacities were all larger than 1.4 mg. And samples could be stored stably at room temperature for 7 days. The selectivity of this method was good. Results of status quo survey indicated that the PAEs pollution in the air of plastic production logistics was not serious, and no obvious clinical symptoms and signs were found in those occupationally-exposed workers. This method meets the demand of the Monitor Investigating Guidelines on Poisons in Workplace Air, and thus then could be applied to determine PAEs in the air of plastic production logistics.

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