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Fresh goji (Lycium barbarum L.) berries were treated with high-concentration (50% and 90%) oxygen shocking for 30 min and then stored at 0 ± 0.5 °C for 30 d. Decay, aerobic plate count, firmness, weight loss, total soluble solid (TSS), and titratable acidity (TA) were evaluated during storage. A total of 90% O2 shocking more effectively reduced decay and maintained the weight loss and firmness of goji berries. Subsequently, changes in fungi communities were analyzed using high-throughput sequencing (HTS) in the 90% O2-shocking and control groups. The results showed that 90% O2 shocking retained the richness and diversity of fungi communities and the microbiome was related to the quality properties of the fruit. Thus, we inferred that high oxygen shocking inhibited the development of natural decay and maintained the satisfying quality of goji berries by affecting the fungi community composition, which reduced the growth of pathogenic fungi and harmful saprotrophic fungi in the genera, such as Filobasidium sp., Alternaria sp., and Cladosporium sp. We provide a new insight into the disease development and quality changes during the storage of postharvest goji berries.

In classical Fourier optics, an optical imaging system is regarded as a linear space-invariant system which is only an approximation. Especially in digital holography, the space-variance effect has a great impact on the image quality and cannot be ignored. Therefore, it is comprehensively investigated in this article. Theoretical analyses indicate that, the space-variance effect is caused by linear frequency modulation and ideal low-pass filtering and it can be divided into three states: approximate space-invariance state, high-frequency distortion state, and boundary-diffraction state. Classical Fourier optics analysis of optical imaging systems only considers the first. Regarding the high-frequency distortion state, the closer the image field is to the edge, the more severe is the distortion of high-frequency information. As for the boundary-diffraction state, in addition to the distortion of high-frequency information in the margin, a prominent boundary-diffraction phenomenon is observed. If the space-variance effect of the imaging lens is ignored, we predict that no space-variance effect in image holography will occur when the hologram is recorded at the back focal plane of the imaging lens. Simulation and experimental result were presented to validate our theoretical prediction.

Fast and robust small infrared (IR) target detection is a challenging task and critical to the performance of IR searching and tracking (IRST) systems. However, the current algorithms generally have difficulty in striking a good balance between speed and performance. In this letter, we propose a new approach to small IR target detection that can significantly accelerate the detection process by first performing a fast adaptive masking and scaling algorithm. We then propose to enhance the target characteristics and suppress the background clutter using both contrast and gradient information. Finally, we propose to accurately extract the targets via iterative segmentation. The experimental results demonstrated that our proposed method yields the best and the most robust performance, with a speed of at least two times faster than the state-of-the-art methods.

Sugar is crucial as an essential nutrient for humans as well as for providing texture, sweetness and so on to food. But with the rise in people's pursuit of health, it is becoming increasingly clear that excessive consumption of sugar can locate a load on the body. It has been that excessive sugar is associated with many diseases, such as dental caries, obesity, diabetes, and coronary heart disease. Therefore, researchers and industries are trying to reduce or substitute sugar in food without affecting the sensory evaluation. Substituting sugar with sweeteners is alternatively becoming the most traditional way to minimize its use. So far, the sweeteners such as stevia and xylitol have been are commercially applied. Several studies have shown that technological innovation can partially compensate for the loss in sweetness as a result of sugar reduction, such as cross-modal interactions that stimulate sweetness with aroma, nanofiltration that filters disaccharides and above, enzyme-catalyzed sugar hydrolysis, and microbial fermentation that turns sugar into sugar alcohol. This review summarizes these studies to enhance the safety and quality of sugar-reduced products, and will provide some theoretical frameworks for the food industry to reduce sugar in foods, meet consumers' needs, and promote human health.

Additional value creation is a critical characteristic of innovative products. Co-design is regarded as an effective approach to creating additional experience value through customer engagement in the product development process. It does not only benefit the comprehension of customer desires but also the inspiration for creating and increasing customer loyalty. However, some barriers may exist in value-creation chains in many creative industries, such as the designer-driven product design, forecast-based marketing, homogeneity of products, long product and development cycles, mass production and so forth. As a typical creation-intensive industry, the fashion industry is focused on in this paper to be surveyed in terms of practices of co-design. This paper has analysed the co-design practices in the fashion industry in terms of market research, design model and manufacturing. Several practitioners who implement co-design strategy in fashion product development have been observed and analysed from the perspective of the value creation chain. The study result demonstrates that customer involvement, co-creating design method, collaborative product development mechanism are the essential aspects of the implementation of co-design in the fashion industry. The significance of this study is not only to offer an effective approach for the fashion industry to survive in increasingly competitive markets but also to point out the developing direction of the relative creative industries. In the conclusion, the paper suggests that further studies related to co-design need to be addressed and would primarily concern themes about the various additional values for innovative products and services and mass customization in creative industries.

We report palladium–BIAN–NHC chloro dimer complex, [Pd(BIAN–IPr)(μ-Cl)Cl]2. This rapidly activating catalyst merges the reactive properties of palladium chloro dimers, [Pd(NHC)(μ-Cl)Cl]2, with the attractive structural features of the BIAN framework.

This study investigated the changes in the structural and functional properties of various adlay starch-based polymers that occur during low moisture extrusion. The water absorption index, water solubility index, color, and morphological, pasting, and thermal properties of the adlay flours were investigated. Extrusion significantly decreased their contents (starch > protein > fiber > lipids). The color of the adlay flour darkened after extrusion, primarily due to the Maillard reaction and caramelization. Scanning electron microscopy revealed various cracks, pits, and holes on the surface of the extruded flour without defatting for both the extruded brown adlay and the extruded polished adlay. Extrusion caused molecular degradation of the extruded starch, decreasing its swelling power in hot water. The ΔH values (0.19-0.71 J/g) of the extrudates revealed that the starch granules were not fully gelatinized. These results provide a theoretical basis for further explorations of the interactions of adlay macromolecules by extrusion.

Frozen storage is most widely adopted preservation method to maintain food freshness and nutritional attributes. However, at low temperature, food is prone to chemical changes such as protein denaturation and lipid oxidation. In this review, we discussed the reasons and influencing factors that cause protein denaturation during freezing, such as freezing rate, freezing temperature, freezing method, etc. From the previous literatures, it was found that frozen storage is commonly used to prevent freeze induced protein denaturation by adding cryoprotectants to food. Some widely used cryoprotectants (for example, sucrose and sorbitol) have been reported with higher sweetness and weaker cryoprotective abilities. Therefore, this article comprehensively discusses the new cryopreservation methods and providing comparative study to the conventional frozen storage. Meanwhile, this article sheds light on the freeze induced alterations, such as change in functional and gelling properties. In addition, this article could be helpful for the prolonged frozen storage of food with minimum quality related changes. Meanwhile, it could also improve the commercial values and consumer satisfaction of frozen food as well.

Computer vision plays a key role in measuring the relative posture and position between spacecrafts, especially in various close-range space tasks. As one of the essential steps for computer vision, camera calibration is important for obtaining precise three-dimensional contours of a space target. The focal length of on-orbit zoom cameras constantly changes. Thus, it is practical to calibrate the focal length rather than other intrinsic camera parameters. However, traditional calibration targets, such as checkerboards, cannot be used to calibrate a space camera in orbit. To address this problem, we propose a two-step process for focal length calibration. In the first step, the initial estimate of the camera focal length was generated with vanishing points obtained from the solar panels of satellites. In the second step, the initial solution was optimized by the particle swarm optimization algorithm. The results of the simulations and laboratory experiments confirmed the accuracy, flexibility, and good antinoise interference performance of the proposed method. Thus, the proposed method has practical significance for space tasks, such as space rendezvous-docking and on-orbit maintenance.

To avoid exhaustive calibration of the shifter device in point diffraction interferometers, we present a dimension-reduction-based method to reconstruct the phase map from more phase-shifting fringe patterns with three or more frames. The proposed method assumes that the intensity space can be described adequately by the sine and cosine of multiple phase shifts introduced, which are the basis of the intensity space. Then, low-dimensional approximations of high-dimensional intensity spaces are determined by the newly developed reduced basis decomposition technique. Finally, the phase is reconstructed using the low-dimensional surrogates of the intensity spaces without the knowledge of accurate phase steps. Numerical and experimental studies demonstrated that the proposed method outperforms the existing popular phase reconstruction techniques in terms of accuracy and efficiency. Moreover, the performance of the proposed method is not limited by variations in the background and modulation, unlike the existing phase-shifting-algorithm-based approaches.

Three-dimensional (3D) printing is a new technique used to construct complex geometric forms for personalized nutrition and customization. With good rheological and gelling properties, starch materials have great potential in the 3D printed food industry. The successful printing of materials depends on various aspects, and current researches have focused on discussing the influence of the rheological properties of starch materials on printing, while the researches on the printing characteristics with other starch properties, material processing methods, printing process parameters are still insufficient. This review mainly focuses on the relationship between the material properties of starch foods and hot extrusion 3D printing, discussing the influence of material properties (rheology, adhesiveness, thermal properties, microstructure and component interaction) on the feasibility of printing. In addition, the effects of additives (hydrocolloids, lipids, fiber, protein, salt and other), processing methods, and process parameters (nozzle diameter, print height, print speed, and throughput) on printing are reviewed.

Biomedical signal processing is the utilization of digital signal processing techniques, such as Fourier transform, filtering, spectral estimation and wavelet transform to biomedical complications, such as the analysis of breathing cycle, cardiac signals, brain signals, etc. Digital filters are used to preserve the in-band signals and to block out-of-band noise. Low-pass, high-pass, band-pass, and band-stop filters are commonly used for filtering applications. The digital signal processing (DSP) concepts can be used for other biomedical applications such as biomedical imaging (MRI, CT, X-ray, PET, ultrasound) and genomic signal processing too. The experiments such as denoising corrupted ECG signals, respiratory artifacts removal, and an identification of rhythmic patterns from EEG signals with spectrogram analysis are performed. Matlab R2016b tool is used for this study. Finally, the assessment, survey and feedback results from the student are tabulated for the better improvement of the course study.

Image detail enhancement is critical to the performance of infrared imaging systems because the original images generally suffer from low contrast and a low signal-to-noise ratio. Although conventional decomposition-based methods have advantages in enhancing image details, they also have clear disadvantages, which include intensive computations, over-enhanced noise, and gradient reversal artifacts. In this paper, we propose to accelerate enhancement processing by using a fast guided filter and plateau equalization. Our method consists of image decomposition, base and detail layers processing, and projection of the enhanced image to an 8-bit dynamic range. Experimental results demonstrated that our proposed method achieves a good balance among detail enhancement performance, noise and gradient reversal artifacts suppression, and computational cost, with a frame rate around 30 fps for 640 × 512 infrared images.

Defective pixel concealment is a necessary procedure in infrared image processing and is widely used. However, current approaches are mainly focused on the concealment of isolated pixels and small defective pixel clusters. Consequently, these approaches cannot meet the requirements when applied to infrared detectors with large defective pixel clusters. In this paper, we present a novel and comprehensive approach to processing the image data acquired from infrared imagers with large and small defective pixel clusters. Our approach consists of preprocessing, coarse concealment, high dynamic range enhancement, and fine concealment by generative adversarial networks. Experiments using mid-wave infrared and long-wave infrared images demonstrated that the proposed approach achieves better results than the best conventional approach, known as transforming image completion, with the peak signal-to-noise ratio and structural similarity metrics improved by 2.7063 dB (16.3%) and 0.1951 dB (34.1%), respectively.

The effects of extrusion treatment on the structure and properties of adlay (Job’s tears) were investigated. Adlay flour was extruded through a twin-screw extruder with different parameters, including barrel temperature (80–160°C), moisture content (19–27%), and screw speed (170–330 rpm). The results showed that although the expansion index increased with increasing temperature, an increase in moisture content significantly decreased the EI (p<0.05). Extrusion improved the water solubility index and water absorption index of adlay flour (p<0.05). Furthermore, analysis of the gelating properties revealed that the structure and function of adlay flour had radically changed. After extrusion, the viscosity of the adlay flour decreased (peak viscosity decreased by more than 1000 cP), and its fluidity increased. The rheological data were modeled by the Herschel–Bulkley model. X-ray diffraction experiments showed that extrusion contributed to a decrease in relative crystallinity. Scanning electron microscopy revealed that extrusion damaged the basic structure of adlay flour, causing holes and pits on the extrudate surface. Compared to the native adlay flour, the extrusion resulted in significantly changing the pasting, gelating, thermal, rheological, and morphological properties of adlay flour. In conclusion, the extrusion can alter adlay characteristics, but it is necessary to choose appropriate conditions to attain the desired properties.

Based on 300 t top-bottom combined blowing converter bottom air brick location layout problems, ANSYS Fluent software is adopted to establish the three-dimensional model, which simulated the change after the location of the four air brick at the bottom of the flow of molten steel in the converter. The results show that when the bottom blow flow is constant, the four bottom permeable bricks should adopt asymmetric staggered layout, which is beneficial to uniform converter flow field. At the same time, it was found that the angle of the bottom-blown gas supply element is different and the influence on the wall scour is different. When the position of the bottom blown air brick is determined, the inclination angle of the air supply element is 10°, the molten steel has relatively less erosion on the furnace wall of the converter, the flow field in the converter is more reasonable, and the cost is saved for the converter smelting.

Computer vision plays a key role to measure the relative posture and position between the spacecrafts, especially in various important space tasks. As one of the essential steps for computer vision, camera calibration is important for obtaining precise three-dimensional contours of the space target. However, it is impossible to use the traditional calibration targets to calibrate the space camera in orbit. To solve this problem, in this paper, we attack the on-orbit space camera calibration problem by using two steps. First, we only use two images of the solar panel, which is a commonly used element of majority human-made spacecraft, to generate an approximate initial estimation of the camera intrinsic parameters. In order to improve the robustness and accuracy of our method, the second step optimizes the initial solution by using an improved genetic algorithm (IGA). Simulated and real experiments prove that the proposed method is accurate and flexible, and shows good robust performance. Therefore, our method has realistic significance for various space tasks.

Thermal design is highly related to the performance of space cameras as temperature changes cause thermal displacements of the cameras’ optical and mechanical systems, consequently affecting imaging quality. However, most existing thermal design methods for space cameras focus on several thermal design parameters without a comprehensive and quantitative analysis. Therefore, we proposed an optimization thermal design method for space cameras based on thermo-optical analysis and the Taguchi method. We first established the thermal balance equations of space cameras, and by analyzing the thermal design parameters in the equations, we identified the key parameters that affect the temperature field, thermal displacements, and imaging quality of the camera. Furthermore, we evaluated the influence of each thermal design parameter on imaging quality based on the integrated thermo-optical analysis. Thereafter, we applied the Taguchi method to quantitatively calculate the effect of each thermal design parameter on imaging quality. Finally, we implemented an optimal thermal control scheme for space cameras based on the results of the Taguchi method. The experimental results demonstrated that the proposed method is reliable and efficient and would be beneficial to researchers working on the thermal design of optical instruments.

Heat soaking is an essential factor deciding the final quality of hard-to-cook grains. In this study, the morphological structures, visualization features, and physicochemical characteristics of adlay seeds soaked at 30–70 °C were investigated compared with waxy rice (easy to cook). The morphology of macromolecules and section cracks were observed by scanning electron microscopy and light microscopy as these are the crucial factors for penetrate water penetration, which showed that starch granules were slightly eroded when adlay seeds were soaked at 70 °C. The MRI images showed that at higher soaking temperatures, the moisture of soaked adlay seeds was distributed more evenly across a gradient. Meanwhile, heat soaking has a minor effect on starch and protein content of adlay seeds, and the proportion of bound water of adlay seeds slightly declined after heat soaking. Moreover, hardness analysis and pasting measurements exhibited structural changes and viscosity transition in the grains. However, the contribution of heat soaking to the infrared spectrogram and relative crystallinity of adlay seeds was insignificant. This study provides effective methods to evaluate changes in adlay seeds during heat soaking and explains why it is hard to cook.

The influences of the changes in geometrical factors, including the space bar thickness, the tube pitch in the first layer, the tube external diameter, the number of layers and the centre core diameter on flow and heat transfer performances in multi-stream spiral-wound heat exchangers are numerical investigated. The shell-side and tube-side Nusselt number and pressure drop per unit length increase with the increase of number of layers, centre core diameter, and tube external diameter, but decrease with the increase of space bar thickness and tube pitch in the first layer. Quantitatively estimation of the affecting performances of these five geometrical parameters is implemented by using the Taguchi method, and the result shows that the contribution rate of them are more than 5%. Thus, the multivariate correlations with the main geometrical parameters considered are developed for shell-side Nusselt number and friction coefficient. (C) 2015 Elsevier Ltd. All rights reserved.

The spiral-wound heat exchangers are widely used in chemical industrial applications, but the mechanism of flow and heat transfer in shell side has not been clarified yet. A three-dimensional model is developed based on the FLUENT software in this study, with emphasis on quantifying the effects of the main geometry parameters, such as the number of tube bundles, the number of tube layers, the thickness of space bars, the number of tubes per circle in the first layer, the tube external diameter, the central cylinder diameter, and the tube pitch in the first layer, on the flow and heat transfer. Based on the numerical simulation results, the Taguchi method is used to estimate the effect of these geometrical factors on flow and heat transfer and the contribution rate of every factor is obtained. Meanwhile, the multivariate correlation is developed by MATLAB software to calculate the Nusselt number and friction factor in the shell side.

With the rapid development of science and technology and the promotion of many local wars in the world, altitude optical sensor mounted on unmanned aerial vehicle is more widely applied in the airborne remote sensing, measurement and detection. In order to obtain high quality image of the aero optical remote sensor, it is important to analysis its thermal-optical performance on the condition of high speed and high altitude. Especially for the key imaging assembly, such as optical window, the temperature variation and temperature gradient can result in defocus and aberrations in optical system, which will lead to the poor quality image. In order to improve the optical performance of a high speed aerial camera optical window, the thermal/structural/optical integrated design method is developed. Firstly, the flight environment of optical window is analyzed. Based on the theory of aerodynamics and heat transfer, the convection heat transfer coefficient is calculated. The temperature distributing of optical window is simulated by the finite element analysis software. The maximum difference in temperature of the inside and outside of optical window is obtained. Then the deformation of optical window under the boundary condition of the maximum difference in temperature is calculated. The optical window surface deformation is fitted in Zernike polynomial as the interface, the calculated Zernike fitting coefficients is brought in and analyzed by CodeV Optical Software. At last, the transfer function diagrams of the optical system on temperature field are comparatively analyzed. By comparing and analyzing the result, it can be obtained that the optical path difference caused by thermal deformation of the optical window is 138.2 nm, which is under PV ≤1 4λ . The above study can be used as an important reference for other optical window designs.