A coin-tap method of composite materials non-destructive testing based on improved grey clustering

Aiming at the problems of low reliability and complex operation of traditional coin-tap test of composite material,this paper introduces the grey system theory and achieves better performance.The response signals of coin-tap are classified through the grey clustering based on relation analysis,and corresponding improvements are made to the calculation method of the relation degree of nearness.First,the time history of acceleration is taken as the system behavior sequence.The improved correlation calculation method is used to solve the relation degree of nearness between the sequences,and the matrix of degree of grey relation is constructed based on this.Then,the sequence groups are summarized through the matrix,and the response signals of coin-tap are qualitatively classified according to the location of the reference sequence.Finally,the defect detection of composite materials is completed without pre-testing.The test results show that the accuracy of the coin-tap test based on improved grey clustering reaches 100%,which simplifies the operation steps while ensuring the reliability of the coin-tap test results.

Sugar Cane （Saccharum officinarum L.） Analysis through Biospeckle and Spectroscopy （NIR）

The objective of this paper was to evaluate the sugar and water content in sugar cane samples by means of twonon-destructive techniques in comparison with conventional methods. One non-destructive technique is the Biospeckle, aninteraction between the laser and the biological material which provides information about the material. The other technique is thenear infrared spectroscopy （NIR）. The Biospeckle technique has been constantly used in agricultural engineering. In this paper, therelation between the water and the sugar contents were obtained. The results for the Biospeckle were acquired through the moment ofinertia （MI）. The data acquired through already consolidated methodologies were used to quantify the samples＇ water and sugarcontents, correlating to the spectroscopy results and also to the Biospeckle. It was obtained a high determination coefficient （R^2 =0.9287） between the predicted Brix by the model generated by NIR spectroscopy and Brix measured by refractometer. It was alsopossible to differentiate the water contents of the sugar cane samples both externally lit （husk） and internally lit （cut） by Biospeckleanalysis through the calculation of MI. It is possible to evaluate the water content and the sugar content in samples combiningBiospeckle and NIR spectroscopy, which are non-invasive and non-destructive methods.

Tomatoes Maturation Analysis with Reflectance Spectral Images

The demands for high quality products are increasing in the market, so several tests are performed. These analyses are destructive, time consuming and sometimes expensive. The spectral imaging technique is an alternative that can reduce costs and time and increase the efficiency and cost-effectiveness of these analyses. In this context, the aim of this study was to verify the spectral behavior of the tomato in function of the maturation and its potential use for non-destructive evaluation of food quality. Eighty tomatoes of the Italian group were selected in four stages of maturation （green, pink, light red and red）. Images were collected in wavelengths 480 nm to 710 nm （every 10 nm）. After the images were collected, the fruits were submitted to the physical-chemical analyses. The following parameters were analyzed： color, color index （CI）, pH, soluble solids （SS）, total titratable acidity （TTA） and ratio （SS/TTA）. After characterization the mean spectrum was obtained by the extraction of the spectral characteristics. It was observed that the spectral behavior was the same for all stages of maturation. It was possible to differentiate the green tomatoes in the wavelengths from 520 nm to 560 nm and from 610 nm to 660 nm. These intervals represent the area of reflection of chlorophyll and lycopene, respectively. Near the wavelength 560 nm, the highest absorbance was recorded by ripe tomatoes due to the concentration of lycopene. It is concluded that the best wavelengths for analysis are those in which green has the highest reflectance and it is possible to apply this technique for non-destructive analysis of the maturation of tomatoes.

Relating estimates of wood properties of birch to stem form, age and species

Birch has long suffered from a lack of active forest management,leading many researchers to use mate-rial without a detailed management history.Data collected from three birch(Betula pendula Roth,B.pubescens Ehrh.)sites in southern Sweden were analyzed using regression analysis to detect any trends or differences in wood proper-ties that could be explained by stand history,tree age and stem form.All sites were genetics trials established in the same way.Estimates of acoustic velocity(AV)from non-destructive testing(NDT)and predicted AV had a higher correlation if data was pooled across sites and other stem form factors were considered.A subsample of stems had radial profiles of X-ray wood density and ring width by year created,and wood density was related to ring number from the pith and ring width.It seemed likely that wood density was negatively related to ring width for both birch species.Linear models had slight improvements if site and species were included,but only the youngest site with trees at age 15 had both birch species.This paper indicated that NDT values need to be considered separately,and any predictive models will likely be improved if they are specific to the site and birch species measured.

The non-destructive analysis of ancient jade artifacts unearthed from the Liangzhu sites at Yuhang,Zhejiang

Samples of the jade artifacts unearthed from the Liangzhu sites at Yuhang (Fanshan,Yaoshan, Huiguanshan and Tangshan) of Zhejiang province were described. The chemical composition, phase and jade structure of a hundred and more intact samples were analyzed by the non-destructive techniques of PIXE, XRD and laser Raman spectroscopy. Results showed that the minerals of the jade artifacts mostly belonged to tremolite and tremolite-actinolite. Relationship of the civilization development in the Neolithic age and the application of tremolite type mineral in jade artifacts was discussed. The contents of rare and trace elements in tremolite jade artfacts and in mineral samples were measured for the first time. The possible mineral sources of these tremolite type jade artifacts were discussed.

55 Years of Holographic Non-Destructive Testing and Experimental Stress Analysis:Is there still Progress to be expected?

Holographic methods for non-destructive testing,shape measurement,and experimental stress analysis have shown to be versatile tools for the solution of many inspection problems.Their main advantages are the non-contact nature,the non-destructive and areal working principle,the fast response,high sensitivity,resolution and precision.In contrast to conventional optical techniques such as classical interferometry,the holographic principle of wavefront storage and reconstruction makes it possible to investigate objects with rough surfaces.Consequently,the response of various classes of products on operational or artificial load can be examined very elegantly.The paper looks back to the history of holographic metrology,honors the inventors of the main principles,discusses criteria for the selection of a proper inspection method,and shows exemplary applications.However,the main focus is on modern developments that are inspired by the rapid technological process in sensing technology and digitization,on current applications and future challenges.

Transient-Spatial Pattern Mining of Eddy Current Pulsed Thermography Using Wavelet Transform

Eddy current pulsed thermography（ECPT） is an emerging Non-destructive testing and evaluation（NDT E） technique, which uses hybrid eddy current and thermography NDT E techniques that enhances the detectability from their compensation. Currently, this technique is limited by the manual selection of proper contrast frames and the issue of improving the efficiency of defect detection of complex structure samples remains a challenge. In order to select a specific frame from transient thermal image sequences to maximize the contrast of thermal variation and defect pattern from complex structure samples, an energy driven approach to compute the coefficient energy of wavelet transform is proposed which has the potential of automatically selecting both optimal transient frame and spatial scale for defect detection using ECPT. According to analysis of the variation of different frequency component and the comparison study of the detection performance of different scale and wavelets, the frame at the end of heating phase is automatically selected as an optimal transient frame for defect detection. In addition, the detection capabilities of the complex structure samples can be enhanced through proper spatial scale and wavelet selection. The proposed method has successfully been applied to low speed impact damage detection of carbon fibre reinforced polymer（CFRP） composite as well as providing the guidance to improve the detectability of ECPT technique.

Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

34 samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

Degradation diagnosis of lithium-ion batteries using AC impedance technique in fixing the state of charge of an electrode

A sustainable society requires an increase in electrified vehicles(xEVs) with a low environmental impact. Among various types of xEVs, battery electric vehicles (BEVs) with lithium-ion batteries(LIBs) have received considerable research attention.

Non-destructive detection of the fruit firmness of Korla fragrant pear based on electrical properties

In order to achieve the non-destructive detection of the firmness of Korla fragrant pear during the ripening period,the characteristic variables integrating the parallel equivalent inductance(Lp),quality factor(Q),parallel equivalent capacitance(Cp),dissipation factor(D),parallel equivalent resistance(Rp)and impedance(Z)were formulated through principal component analysis(PCA).Further,based on the characteristic variables,the models were established for predicting the firmness of Korla fragrant pear by using the generalized regression neural network(GRNN)and back-propagation neural network(BPNN).The results showed that firmness has significant correlations with the six electrical parameters.The first two principal components(PCs)were selected as the characteristic variables of the electrical parameters.GRNN exhibited the best performance in predicting firmness(R2=0.9628,RMSE=0.383).The results could provide important references for non-destructive detection of the quality of Korla fragrant pear.

Organomercury Captured by Lyase Overexpressed <i>Escherichia coli</i>and Its Evaluation by <i>In-Cell</i>Radiometry*

Organomercury lyase (MerB) overexpressed in Escherichia coli captured and decomposed organomercury compounds, and it has been detected by radioactive analysis with neutron irradiation. Genetically modified E. coli captures a lot of mercury from a cultivation solution with about 80% recovery, when the bacteria are growing during 24 to 72 hours. Since the modified E. coli has no additive gene for mercury metabolism, the bacteria could hold mercury tightly by the MerB enzyme in their cell and do not release them into medium. In the later, 72 hours after, bacteria have less recovery ratio;it may be affected by undecompsed mercury compounds in bacteria growth. The recovery ability of the bacteria would not be changed by addition of the MerB producing reagent (IPTG). A quantitative value of mercury atom is estimated by an emission of γ-ray by reactor neutron from a dried cell or solution on a filter paper, which is available for nondestructive testing of bacteria holding mercury atoms. In this method an efficient recovery system of toxic mercury from a polluted solution has been archived without destruction of samples, so called in-cell analysis.

Scientific Investigation of the Paintings from the Agarbiciu (Cluj County) Wooden Church

The investigation of the painting materials (pigments, binders and varnish) of Agarbiciu wooden church painted walls was done by employing both nondestructive (XRF and reflection FTIR spectroscopy for pigments) and destructive methods (FTIR spectroscopy and GC-MS spectrometry for pigments and binders). The digital restoration of the interior of the wooden church was done using the physical-chemical composition of the painting layer, a metadata set that describes the timeline, detailed photographic documentation and the 3D scanned interior of the church.

Models for Estimation of Single Leaf Area of Mangrove TreesModels Trees based on Leaf Length and Widthbased Width

Leaf area is an important parameter for modeling plant growth and physiological processes.It is very expensive and difficult for measuring leaf area by means of Leaf Area Meter,therefore,it’s quite necessary to obtain one simple model for estimation of leaf area of mangrove tree.The models for estimation of leaf area of 3 species of mangrove trees were developed based on leaf length and width.Totally,leaf area(LA),leaf length(L)and width(W)were measured from 450 fresh leaves of major three species of mangrove trees in Zhangjiang Estuary Mangrove National Natural Reserve,Fujian province.The actual leaf area of the plant was measured with the help of ArcGIS software and regression model was fitted.The majority of the data(80%)were used for model calibration,and the remaining data(20%)were used for model validation.All the leaf areas of 3 species of mangrove trees had been significant correlation between L,W,L·W,L2,W2and(L+W)2,so the factors could be constructed into a regression model with leaf area.Six models for estimation of leaf area selected were significantly(p<0.001)regressed with L,W and the functions of these dimensions.All models were linear relationships.Based on goodness of fit,prediction ability and residual performance,it was found that model 3 could best describe the relationship between leaf area and leaf length and width.By means of regression analysis,the following models were developed:LA=0.28+0.66L·W(R2=0.980)for Kandelia candel,LA=0.09+0.73L·W(R2=0.983)for Avicennia marina,LA=0.52+0.72L·W(R2=0.990)for Aegiceras corniculatum,respectively.The study provided a simple,reliable and non-destructive method for estimating single leaf area.It had a good potential in the functional structural model of mangrove tree.

Prediction of salmon (Salmo salar) quality during refrigeration storage based on dielectric properties

Dielectric properties are validated to be correlated with the changes of food quality during 4℃ storage,thus it could be used as predictive indicators for the quality parameters of salmon(Salmo salar)during cold storage.An open-ended coaxial detection method was used to determine the dielectric properties(dielectric constantε'and dielectric lossε")of salmon at the frequency range of 20-2500 MHz,and to explore the relationship between dielectric properties and volatile base nitrogen(TVB-N),thiobarbituric acid reactants(TBARS),total viable counts(TVC),pH and K-value in salmon fillets during storage for 7 d.Results showed that the TVB-N,TBARS,TVC and K-value of salmon increased linearly with the increase of storage time,and the pH decreased firstly and increased subsequently.Also,the dielectric properties(ε'andε")decreased with the increase of frequency,and increased with the increase of storage time.During 7 d storage,ε"increased the most at the frequency of 27.12 and 40.68 MHz,while at the frequency of 915 MHz and 2450 MHz,the increase ofε"was smaller.Results analyzed by Pearson correlation analysis showed that significant correlation(p<0.01)was found betweenε"and TVB-N and TBARS at the frequency of 27.12,40.68,100.00,300 and 915 MHz.The results of the partial least square(PLS)model showed that all the determination coefficients(R2pred)were over 0.900.Especially for TBARS,the R2pred of PLS-ε'and PLS-ε"were 0.913 and 0.920,respectively,and the root mean square error of prediction(RMSEP)were 0.041 and 0.039,respectively.However,the highest R2pred for PLS-ε'and PLS-ε"both occurred in TVB-N.Also,the predicted values against measured values of TVB-N,TBARS and TVC of salmon presented a good linear relationship.The linear coefficient R2 of TVB-N,TBARS and TVC for PLS-ε'were 0.937,0.910 and 0.917 respectively,and 0.942,0.917 and 0.933 respectively for PLS-ε".The results demonstrated the dielectric properties combined with PLS analysis can be used as a rapid and non-destructive method to predict quality parameters of salmon during 4℃ storage and could be further applied to other aquatic products.