Non-destructive Technology Research Articles

Computed tomography evaluation of gilt growth performance and carcass quality under feeding restrictions and compensatory growth effects on the sensory quality of pork

Restricted feed can affect the body composition of pigs. Body composition can be studied non-destructively in live pigs using computed tomography (CT). The objective was to investigate the effect of different feeding restriction strategies on the productive and carcass quality parameters of gilts during growth via CT images and the effects of such strategies on meat quality, sensory properties and consumer preferences. Moreover, we sought to determine whether CT is a suitable tool for this purpose in this type of study. Thus, 36 Pietrain x (Large White x Landrace) gilts were assigned to the following three feeding strategies: 1) ad libitum feeding (AL) during all fattening periods (AL-AL); 2) AL feeding between 30 and 70 kg target body weight (TBW) followed by restriction (84% of AL) until 120 kg TBW (AL-RV); and 3) restriction feeding (78% of AL) between 30 and 70 kg TBW followed by AL until 120 kg TBW (RV-AL). When the pigs reached 30, 70, 100 and 120 kg, they were CT scanned to obtain the carcass composition parameters. At 120 kg TBW, the pigs were slaughtered, and the carcass and meat quality was determined. The loins were collected for trained panel evaluation and consumer tests. The panellists evaluated the odour, flavour and texture attributes of cooked loins. A total of 120 consumers scored the overall acceptability, tenderness, odour and flavour. The results showed a decrease of 76% and 80% in the average daily gain and average daily feed intake during the restriction period compared with the ad libitum in the growth phase, respectively, and a decrease of 89% and 87% in these parameters during the fattening phase, respectively. A restriction reduces the body fat content during the period of the restriction. Differences in the carcass and cut composition and meat quality were not observed at the end of the experiment among the treatments. Regarding sensory quality, meat from the animals in the AL-AL treatment was tougher than that from animals in the RV-AL and AL-RV treatments. Nevertheless, these differences were not detected by consumers, who did not provide significantly different scores for acceptability. Thus, when preparing feeding strategies, these results should be considered to optimize costs and increase benefits. Furthermore, computed tomography represents a non-destructive technology suitable for determining carcass composition before slaughter.

New methods for art object conservation and restoration – practical experience in the field: the experience of The True Image Solution Ltd

Previously, scientific examination of works of art was almost exclusively carried out in a specialist laboratory, major gallery or institution. Moving the artwork nearly always involved associated risks and transportation and insurance costs. Founded in 2009, The True Image Solution (TIS) had a vision to bring non-destructive technology to the artwork and to extend the possible range of evaluation by applying other imaging techniques, including ultrasound, flash thermography, X-ray spectroscopy and microwave imaging. In conjunction with English Heritage, these techniques were applied to a wide variety of objects. The results demonstrated that all of these techniques could be successfully carried out in situ and the risk of transportation damage, as well as associated transport and insurance costs, could be eliminated.

Application of Ground Penetrating Radar to Estimate Subgrade Soil Density

Ground penetrating radar (GPR) technology has been widely used in pavement assessment over the last decade. Assessing the subgrade condition and monitoring its temporal variation provide valuable information regarding changes associated with pavement deterioration, allowing for the beneficial prediction of future road maintenance. This paper presents a method to estimate the density and water content of prepared subgrade soils of highly plastic silt using a 2 GHz GPR scan system and a simple exponential model. A bulk density prediction model was developed based on electromagnetic mixing theory to back calculate subgrade soils density. The model developed determines the soil’s dielectric constant, considering dielectric and volumetric properties of the three major components of soil: air, water, and solid particles. A series of laboratory tests was conducted on six (6) soil samples at various density levels to validate the newly developed model. For validation purposes, sand cone and dynamic cone penetration (DCP) tests were performed and compared with the estimated soils strength from GPR data. The results show that the prediction of soils density and stiffness using nondestructive technology helps efficiently forecast not only pavement deterioration, but potential risks to the subsurface pavement structure with all the advances of time saving using air coupled GPR antenna mounted on a moving vehicle.

Rapid Identification of Atmospheric Gaseous Pollutants Using Fourier-Transform Infrared Spectroscopy Combined with Independent Component Analysis

Fourier-transform infrared (FTIR) spectroscopy is a rapid and nondestructive technology for monitoring atmospheric quality. The identification of each component from the FTIR spectra is a prerequisite for the accurate quantitative analysis of gaseous pollutants. Due to the overlap of different gas absorption peaks and the interference of water vapor in the actual measurement, the existing identification methods of gas spectra have drawbacks of low identification rate and the inability to carry out real-time online analysis in atmospheric quality monitoring. In this work, independent component analysis (ICA) is applied to the spectral separation of heavily overlapped spectra of gaseous pollutants. The proposed method is validated by the analysis of mixture spectra obtained in laboratory and actual atmospheric spectra collected from stationary source. The average time consumption of separation process is less than 0.2 seconds, and the identification rate of experimental gases is up to 100%, as shown by the results of peak searching and the analysis of the correction coefficient between the separated spectra and the standard spectra database. The identification results of actual atmospheric spectra demonstrated that the proposed method can effectively identify the gaseous pollutants whose concentration changes in the measured spectra, and it is a promising qualitative spectral analysis tool that can shorten the identification time, as well as increase the identification rate. Therefore, this method can be a useful alternative to traditional qualitative identification methods for real-time online atmospheric pollutant detection.

Nondestructive VIS/NIR spectroscopy estimation of intravitelline vitamin E and cholesterol concentration in hen shell eggs

Designer hen shell eggs, with enhanced or reduced specific components, are used as part of a healthy diet, and such designer eggs must meet certain standards. A fast, nondestructive technology is required in order to ensure that these standards are met. In this study, we investigated the nondestructive estimation of intravitelline vitamin E and cholesterol concentrations in hen shell eggs using visible and near-infrared (VIS/NIR) spectroscopy. The values estimated using partial least-squares regression (PLSR) models were highly correlated with vitamin E concentration measurements by high-performance liquid chromatography and cholesterol concentration measurements by enzymatic analysis. Wavelength selection with the Martens uncertainty test successfully removed unimportant variables and enhanced the models' accuracy and reliability. However, spectral measurements of separated egg yolks with artificially controlled vitamin E and cholesterol concentrations did not afford accurate predictive models. This result for separated yolks, together with band assignments of PLSR models for hen shell eggs, suggested that VIS/NIR spectroscopy can indirectly estimate vitamin E and cholesterol concentrations in hen shell eggs by using information about other components.

Temporal changes in the spatial distribution of physicochemical properties during postharvest ripening of mango fruit

While the temporal ripening behavior of mango is widely documented, the spatial distribution with respect to physicochemical composition remains largely unknown. In this study, ripening behavior of mangos cv. Nam Dokmai was investigated focusing on the variations between the different fruit parts, namely shoulder, cheek, and tip. The temporal results showed typical ripening behavior: color changes in pericarp and mesocarp with increase of a* and b* values and rises in total soluble solids (TSS) and pH, while firmness and titratable acidity (TA) decreased. Sucrose and citric acid were respectively the predominant sugar and acid in this particular cultivar. Relating to spatial variation, the shoulder (near the stem) had the highest TSS, pH, sugar to acid ratio (TSS·TA−1), and sucrose, glucose, and fructose values. The tip showed the highest TA and citric acid content. Generally, the shoulder and tip were observed to ripen faster than cheeks. PCA was used to classify the ripeness of mango based on measured parameters and suggested that the cheek part is recommended for quality measurements. This information is imperative for the fruit handling industry, especially regarding the implementation of non-destructive technologies for quality determination.

Chemical Characterization of Wine Vinegars Belonging to the Vinagre de Montilla-Moriles Protected Designation of Origin, Using Near-Infrared Spectroscopy

Spanish wine vinegars belonging to Vinagre de Montilla-Moriles protected designation of origin (PDO) must satisfy some chemical characteristics. These characteristics are mainly responsible of their high and exceptional quality. This study assessed the potential of near-infrared spectroscopy (NIRS) as a non-destructive technology for characterizing wine vinegars belonging to this PDO. A total of 107 vinegars were used to predict major chemical quality parameters (volumic mass, reducing sugars, total acidity and pH) using a scanning monochromator (spectral range 400–2500 nm) with the spinning module, working in transflectance mode. The models developed showed values for the coefficient of regression for cross-validation between 0.95 and 0.99 for volumic mass, reducing sugars and total acidity. Therefore, the results confirm that NIRS technology combined with linear regression strategies such as the modified partial least squares (MPLS) regression can indeed respond to the needs of the vinegar cellars and help them to measure the commonest chemical quality parameters of wine vinegars belonging to Vinagre de Montilla-Moriles (PDO), especially in the case of vinegars with different sugar contents (dry, semi-sweet, sweet and balsamic). However, the number of vinegars as well as their variability should be increased in order to obtain more robust models.

Study on Void Structure Reconstruction of Asphalt Mixture by X‐Ray Computed Tomography and Otsu’s Method

The purpose of this paper is to obtain the pore distribution of asphalt mixture accurately by nondestructive technology. Specimens prepared with four gradations of asphalt mixtures were scanned using X‐ray computed tomography (CT) which was used to measure air void sizes at different depths within specimens. The air void distributions of obtained CT images were analyzed using ring blocking segmentation combining Otsu’s method, which provided an accurate estimate of air voids in asphalt mixtures. The image processing results showed that air void distribution was not uniform in the specimens; higher air void concentrations were found at the top and bottom of the specimen, and lower, in the rest of the sample depth. The air void sizes of SUP13 and AC13 are mainly distributed between 0.15 to 0.2 mm, while PA13 and SMA13 are 0.4 to 0.65 mm and 0.4 to 0.7 mm, respectively. It is believed that the CT pictures processed by the ring blocking segmentation combining Otsu’s method is feasible and rational to capture the air voids size and content of asphalt mixtures.+

Visualization of Interaction of Laser Pulse-Gastric Tumor by COMSOL Based on Finite Element Analysis

Photoacoustic imaging is an emerging technology based on the photoacoustic effect that has developed rapidly in recent years. It combines the high contrast of optical imaging and the high penetration and high resolution of acoustic imaging. As a non-destructive biological tissue imaging technology, photoacoustic imaging has important application value in the field of biomedicine. With its high efficiency bioimaging capabilities and excellent biosafety performance, it has been favored by researchers. The visualization of photoacoustic imaging has great research significance in the early diagnosis of some diseases, especially tumors. In photoacoustic imaging, light transmission and thermal effects are important processes. This article is based on COMSOL software and uses finite element analysis to construct a physical model for simulation. Through laser pulses into the stomach tissue containing tumor, the physical process of light transmission and biological heat transfer was studied, and a photothermal model composed of two physical fields was built, and finally a series of visualization graphics were obtained. This work has certain theoretical guiding significance for further promoting the application of photoacoustic imaging in the field of biomedicine.

X-Ray Diffraction Analysis of Residual Stresses in the Premium Rails Welded by Flash Butt Process

Abstract: This work is distinguished by searching for a non-destructive technology, and X-ray diffraction was validated by the XStress 3000 analyser. Measurements of residual stresses in the welded zone of premium pearlitic rails was performed, rail surface hardness of 370 HB and 0.79% carbon content. The welding of the rails was done by flash butt process, performed by Schlatter GAAS 80 stationary equipment. The results of the tensile and compressive stress measurements identified the residual stresses in the welded zone, with specific zones of tensile stresses misplaced at the weld center, with values up to 391 MPa, and compressive stresses, with values up to -166 MPa, as it moves away rails weld center. An important point of this study is the residual stress measurement considering a complete welding process, including: pre-grinding, flash butt welding, heat treatment, finishing grinding and straightening. Lastly, was observed the welding technique potentially can induce residual stresses at rails.

Tree Growth and Wood Quality in Pure Vs. Mixed-Species Stands of European Beech and Calabrian Pine in Mediterranean Mountain Forests

Mixed-species forests may deliver more forest functions and services than monocultures, as being considered more resistant to disturbances than pure stands. However, information on wood quality in mixed-species vs. corresponding pure forests is poor. In this study, nine plots grouped into three triplets of pure and mixed-species stands of European beech and Calabrian pine (three dominated by European beech, three dominated by Calabrian pine, and three mixed-species plots) were analysed. We evaluated tree growth and wood quality through dendrochronological approaches and non-destructive technologies (acoustic detection), respectively, hypothesizing that the mixture might improve the fitness of each species and its wood quality. A linear mixed model was applied to test the effects of exogenous influences on the basal area index (BAI) and the dynamic modulus of elasticity (MOEd). The recruitment period (Rp) was studied to verify whether wood quality was independent from stem radial growth patterns. Results showed that the mixture effect influenced both wood quality and BAI. In the mixed-species plots, for each species, MOEd values were significantly higher than in the corresponding pure stands. The mixture effect aligned MOEd values, making wood quality uniform across the different diameter classes. In the mixed-species plots, a significant positive relationship between MOEd and Rp, but also significantly higher BAI values than in the pure plots, were found for European beech, but not for Calabrian pine. The results suggest the promotion of mixing of European beech and Calabrian pine in this harsh environment to potentially improve both tree growth and wood quality.

Environmental advantages of visible and near infrared spectroscopy for the prediction of intact olive ripeness

Conventional ripeness analyses performed on olives require different analytical tools, chemicals, sample preparation and they are time consuming. The same analyses performed using an optical and non-destructive technology such as visible and near infrared (vis/NIR) spectroscopy allow prediction of ripeness parameters in a simple and quick way. The purpose of this work is to compare the environmental impact of conventional ripeness analyses and an optical approach performed on olive fruits. The conventional analyses identified as reference were: moisture, oil and phenols content. Life Cycle Assessment was applied to assess the environmental impact. The approach “from cradle to grave” considered all the inputs and outputs of each analysis, including machinery, reagents and energy necessary for analyses. Furthermore, for the optical analysis the activities required for the instrument calibration were also considered. Quantifying the environmental damage, the results showed clear advantages for optical analysis allowing vis/NIR spectroscopy to be defined as a green technology.

Intelligent Diagnostic Control and Management of the Condition of Electrotechnical Equipment

In this paper, we consider intelligent diagnostic systems providing effective control of electric equipment of electric network facilities. To maintain equipment operability, a level model is proposed. The model is distinct in integrating various methods of analyzing and processing dissimilar data of equipment operation in order to reliably assess its technical condition using nondestructive control technologies to determine the real need for maintenance and repair. The model is focused on intelligent support of the electrical personnel activities and involves calculating the integral priority indicator to assess the necessary maintenance activities and choose the most appropriate control actions. A method for diagnostic control during the electric equipment operation, which can be used for electric network facilities of various configurations, is developed. The technique involves the adaptation to equipment operating conditions for the timely identification of defects and reducing the duration of planned and unplanned downtime. The results of technique testing on the example of electrical equipment of oil production facilities are presented. The proposed solutions are considered to be a way to move on to a new generation of smart electric networks.

Process quality control of the manufacturing of Chinese Materia Medica by process analysis technology

Process quality control is essential for the manufacturing of Chinese Materia Medica. Non-destructive monitoring is still a challenge for the quality control of Chinese Materia Medica manufacturing. As the commonly used non-destructive process analysis technology, near infrared spectroscopy, near infrared chemical imaging, and laser-induced breakdown spectroscopy have been applied to the quality control of Chinese Materia Medica manufacturing. The characteristic near infrared bands of 29 natural chemical components have been assigned. Ten spectral pre-processing methods and five variable selection methods have been optimized, respectively. Given the interrelationship among modeling parameters, a system modeling concept was put forward to establish a global model. Accuracy Profile was further proposed as the validation method of models. In addition, the homogeneity of chlorpheniramine maleate tablets from six brands was successfully visualized by near infrared-chemical imaging. As and Hg variation in An-Gong-Niu-Huang Wan have been rapidly monitored by laser-induced breakdown spectroscopy. A systematic modeling method (model establishment, evaluation, and validation) and the non-destructive technology of homogeneity visualization and toxic element detection have been developed for quality control of Chinese Materia Medica manufacturing, which is shown in Figure 1 of the article. These achievements have greatly promoted the research and application of process analysis technology in Chinese Materia Medica manufacturing, laying a solid foundation for the development of intelligent Chinese pharmaceutical industry.

IR thermography applied in church heritage conservation

IRT – infrared thermography has met an extensive popularity among the non-destructive technologies. This paper is presenting some of the monumental church that had been examine with thermovision camera in order to assess the behavior of structure to ageing, earthquake damages, detect hidden characteristics or order anomalies. IRT investigation is based on principle that heat flowing in a material is altered by presence of all kind of anomalies, our job been to discover and interpreting. Thus heat bridges can be detected, heat loses and air leakage can be identify or the presence of mold, moisture is growing in a particular area.

ИСПОЛЬЗОВАНИЕ ЭЛЕКТРООСМОТИЧЕСКОГО ЭФФЕКТА ДЛЯ ОСУШЕНИЯ БАРЬЕРОВ БЕЗОПАСНОСТИ ПРИ ВЫВОДЕ ИЗ ЭКСПЛУАТАЦИИ ЯДЕРНО- И РАДИАЦИОННО ОПАСНЫХ ОБЪЕКТОВ

Актуальность исследования обусловлена необходимостью разработки новых инновационных неразрушающих технологий восстановления целостности и осушения барьеров безопасности на основе смеси природных глин, создаваемых при выводе из эксплуатации ядерно- и радиационно опасных объектов. Цель исследования: выявление физико-химических особенностей глиносодержащего барьерного материала, используемого при создании дополнительных барьеров безопасности при выводе из эксплуатации ядерно- и радиационно опасных объектов, а также разработка и апробация способа осушения таких барьеров электроосмотическим методом. Методы исследования: аналитическое и экспериментальное исследование электроосмотического эффекта, возникающего при осушении барьеров безопасности на основе смеси природных глин. Результаты. Показано, что используемые при выводе из эксплуатации ядерно- и радиационно опасных объектов барьерные материалы на основе бентонита способны сохранять свои уникальные противофильтрационные и противомиграционные свойства на протяжении всего времени потенциальной опасности объекта. Акцентировано внимание на то, что такие барьеры безопасности могут быть подвержены внешнему негативному воздействию (техногенному или природному), что приводит к частичному ухудшению их противофильтрационных и противомиграционных свойств. Доказано, что для восстановления целостности и работоспособности глиносодержащих барьеров безопасности целесообразно использовать методы, не приводящие к ещё большей деградации барьерного материала. Для этих целей предложено использовать электроосмотический метод, основанный на капиллярном движении влаги в электрическом поле. Указанный электроосмотический метод восстановления глиносодержащих барьеров безопасности позволяет концентрировать влагу возле одного из электродов, тем самым осушать прилегающую область глины. Показано, что эффективнее всего удаляется раствор, имитирующий грунтовые воды из пункта глубинного захоронения радиоактивных отходов. При напряжении 31,8 В и расстоянии между электродами 40 мм линейная скорость движения влаги составляет 2,5 мм/мин. Это позволяет полностью осушить глиносодержащий барьер безопасности, обводненный 70 мл раствора, в течение 7–8 часов. Выявлено, что в результате рекомбинации диссоциированных ионов солей и воды на электродах происходит прилипание, спекание и омоноличивание барьерного материала в приэлектродной области. Это позволяет удалить деградированный барьерный материал вместе с электродом. Установлено, что в области концентрирования влаги вблизи катода происходят химические реакции, результатом которых является выделение газообразных продуктов, что позволяет удалять жидкость без использования специальных средств в непрерывном режиме.

Comparison and optimization of models for SSC on-line determination of intact apple using efficient spectrum optimization and variable selection algorithm

Higher accuracy for a prediction model is the unremitting pursuit in the field of optics nondestructive technology. The multipoint full-transmittance spectra ranging from 650 to 1000 nm were acquired at a speed of 0.5 m/s using an on-line spectrum measurement system. The combination of mean normalization and 11 points smoothing were selected as the best spectral preprocessing method for removing undesirable signal excursion and light scatters existed in the original spectra. By investigating the interference of transmittance spectral intensity on the prediction accuracy with the method of efficient spectrum optimization proposed in our study, we found that those transmittance spectra with intensity lower than 0.4 at 920 nm were inefficient for SSC prediction. Furthermore, three different variable selection algorithms were used to select characteristic band for further optimizing the prediction model, the best prediction model was built based on 45 variables selected by random flog (RF) and the performance of the best model was Rpre = 0.9043 and RMSEP = 0.4787 respectively. All mentioned above illustrated that efficient spectrum optimization method coupled with variable selection algorithms were useful for improving the accuracy and robust of prediction model.

Relationships between wood properties of small clear specimens and structural-sized boards in three softwood species

Abstract Research on the mechanical and physical properties of wood is commonly carried out on either small clear specimens or structural-sized boards. The first approach was more frequently utilized in the past, while the latter is more commonly used nowadays. However, there is very little information on how the two approaches relate with one another. This study aimed to quantify the relationships between the mechanical [modulus of elasticity (MOE) and bending strength] and physical properties (density) of both specimen sizes. A total of 1376 structural-sized boards from three different species (Douglas-fir, Norway spruce and Sitka spruce) were tested in bending, after which a small clear specimen was extracted from the undamaged portion of each board and re-tested in bending. Prior to destructive testing, all boards and clear specimens were evaluated using non-destructive technology. Poor-to-moderate relationships were found between all measured mechanical and physical properties of structural-sized timber and small clear specimens. In both specimen sizes, the properties correlated with one another within the same specimen size, as well as across the two sizes. The strength of correlations appears to be somewhat species dependent. Relatively good relationships were identified when comparing the mean tree values of the properties examined, suggesting either method can be used for a tree-level comparison. The non-destructive evaluation of specimens was shown to reflect the measured properties moderately well, with the relationships changing significantly depending on which measured property was being predicted.

Stress-Dependent Magnetic Charge Model for Micro-Defects of Steel Wire Based on the Magnetic Memory Method

ABSTRACTMagnetic memory method (MMM) is widely used for diagnosing ferromagnetic material on early stage as a nondestructive technology, but no clear description exists for the influence of stress on MMM signals at the micro-defect position on the surface of steel wire yet. Hence, based on traditional magnetic charge model, a stress-dependent magnetic charge model that combined the Jiles magneto-mechanical constitutive relation was intended to calculate the MMM signals around micro-defect on surface of steel wire. Meanwhile, the Hp(y) signals on surface of steel wire with different defects were measured during the whole tension test. By comparing the results of theoretical model and experiment, some conclusions can be drawn. First, the position of vale-peak on Hp(y) signals curves can be used to determine the micro-defect on steel wire. Secondly, the vale-peak amplitude (Sv-p) and vale-peak width (Lv-p) of Hp(y) signals curves, as two characteristic parameters of magnetic signals, not only can reflect the variations of defect depth and defect width, but also judge the load subjected by specimen. Sv-p has an approximate growth with the increase of defect depth as a whole, but decreases with the increase of loads. And the effect of load on Sv-p increases with defect depth. Lv-p has an approximate growth with the increase of defect width as a whole, but does not change with the increase of loads. Finally, the stress-dependent magnetic charge model can be better to reflect the changing laws of Hp(y) signals around defect and can be used for the numerical analysis of MMM signals on surface of steel wire.

Magnetic characteristics of atmospheric dustfall in a subtropical monsoon climate zone of China and its environmental implications: A case study of Nanjing

Nanjing is located in the subtropical monsoon climate zone of China. In this study, a series of monthly collections of atmospheric dustfall was performed in different directions from a high-rise building in Nanjing from February 2015 to March 2016. A series of magnetic parameters including χ, χfd%, χARM, SIRM, magnetic hysteresis loops, high-temperature κ-T curves and SEM images was measured from atmospheric dustfall samples. The research shows that the type and size of magnetic minerals within atmospheric dustfall samples in Nanjing are similar to those found in northern cities in China, but the atmospheric dustfall samples in Nanjing have higher magnetic mineral concentrations. Coarse-grained magnetite dominated magnetic minerals. The peak concentrations of magnetic minerals contained from atmospheric dustfall of Nanjing occurred in summer. The relationship between magnetic parameters and meteorological data shows that the high values are mainly influenced by precipitation rather than by wind direction. Combined with results of the SEM images and the weak relationship between magnetic parameters and the data of PM 2.5 and PM10, all these indicate that the atmospheric dustfall of Nanjing is mainly from near-source polluted dustfall rather than from long-distance dustfall. This research suggests that environmental magnetism as a simple, economic and nondestructive technology, will be a useful tool in atmospheric dustfall research.