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As an important parameter in various industries such as metal processing, agriculture, and medicine, the measurement of liquid flow can not only help us ensure the quality of production, but also improve production efficiency. In recent years, the development of computer vision has driven the development of flow detection towards intelligence. As a non-contact, fast measurement, high degree of automation, and high-precision measurement method, image processing technology has gradually been applied to various industries. Many researchers have invested a lot of research work on flow measurement. The representative research and solutions are summarized for more than 20 years, and describes the six main methods used in the flow detection of each fluid. It includes the following aspects: obtaining the flow through the liquid level detection; measuring the volume change rate by detecting the contour of the droplet; detecting the flow through a water ruler; adding markers such as tracer particles and tracer fluid to the liquid; using the interframe displacement of the water surface texture method. The article points out that the accuracy of the flow measurement is mainly affected by the liquid environment, and there are still many problems in the selection of light sources and algorithm research, and the true non-contact has not been achieved. At the same time, the future research trends and development directions are given. Through a large number of literature reviews, a review of the detection of fluid flow is provided, which provides many ideas for the next topic of milk flow detection.

This article introduces an intelligent control medical nursing bed under the control of a single chip microcomputer. It can realize remote monitoring and complete any angle turning. Thus, it will not only be beneficial to recover the patients' condition and prevent the decubitus ulcer, but also ease off the pressure of the family members to take care of the patients.

In this paper, we propose a simple yet effective solution to a change detection task that detects the difference between two images, which we call "spot the difference". Our approach uses CNN-based object detection by stacking two aligned images as input and considering the differences between the two images as objects to detect. An early-merging architecture is used as the backbone network. Our method is accurate, fast and robust while using very cheap annotation. We verify the proposed method on the task of change detection between the digital design and its photographic image of a book. Compared to verification based methods, our object detection based method outperforms other methods by a large margin and gives extra information of location. We compress the network and achieve 24 times acceleration while keeping the accuracy. Besides, as we synthesize the training data for detection using weakly labeled images, our method does not need expensive bounding box annotation., Tech Report, 10 pages

ViBe (Visual Background Extractor) algorithm is a kind of fast and accurate background subtraction algorithm, which is universally applied in video monitoring. The only drawback is the moving target in the first frame would introduce an artifact called ghost. In order to solve this problem, an eliminating ghost algorithm was designed in this paper. The algorithm depended on the foreground and the adjacent background area histogram and similarity measure. Because dynamic background video was easily influenced by background noise and interference, morphological image processing method was used in this paper. Experiments results show that the improved algorithm can quickly solve the ghost, foreground noise and holes problem.

Based on the rigorous coupled wave theory, the narrowband reflect spectral imaging characteristics on two-dimensional photonic crystal are analyzed, and two-dimensional photonic crystal sensor probe biological structure and photonic crystal biosensor system are constructed. The simulation proved that, when the adsorption medium at the surface of two-dimensional photonic crystal are different, the white light narrowband reflection resonance mode peak wavelength would drift, and the drift quantity of the peak wavelength and the refractive index of the adsorptive medium is in a linear relationship. Colored the space imaging spectra of photonic crystal, the changes of the adsorbate refractive index in different area of the photonic crystal surface can be observed , the adsorbate concentration changes can also be got. This conclusion can be applied to biochemical substances, pharmaceutical, biological molecules and environmental pollution detection.

Color recognition plays an important role in Machine Vision and Artificial Intelligence. In this article, a system based on FPGA applying to image acquisition, storage, display and color recognition is designed mainly to complete the recognition and calibration of fixed colors. Color images are captured by the analog camera in the system, which are decoded into standard YCbCr 4:2:2 data streams by AD chip. Then data streams are converted to the data of RGB video format by performing color space conversion. In the RGB color space, the color recognition method is proposed to identify the target color and calibrate on the display device. The experimental results demonstrate that the method can effectively achieve the identification of certain kinds of colors.

The aim of this study was to evaluate the effectiveness of regional hyperthermia combined with lamivudine (LAM) for treatment of chronic hepatitis B (CHB) and explore its possible mechanism. Forty CHB patients were randomly divided into the combination group (treated with regional hyperthermia and LAM ; n=17) and control group (treated with LAM alone ; n=23). Laboratory examinations were performed for hepatic function, hepatitis B virus (HBV) markers, and HBV DNA. Lymphocyte subpopulations including CD3+ (total T cells), CD4+CD8- (helper T cells) and CD4-CD8+ (cytotoxic T cells) were detected with flow cytometry. The side effects and tolerance were observed. Aspartate aminotransferase and HBV-DNA levels were significantly lower in the combination group than in the control group (P< 0.05). Hepatitis e antigen/antibody conversion rate was similar between the two groups, whereas the combination group had significantly higher rates of CD4+/CD8+ T cells than the control group (P< 0.05). Regional hyperthermia combined with LAM is superior to LAM alone for treatment of CHB, which may be achieved by enhancing cellular immune function.

Suspension-emulsion combined polymerization process, in which methyl methacrylate (MMA) emulsion polymerization constituents (EPC) were drop wise added to styrene (St) suspension polymerization system, was applied to prepare polystyrene/poly(methyl methacrylate) (PS/PMMA) composite particles. The influences of the feeding condition and the composition of EPC on the particle feature of the resulting composite polymer particles were investigated. It was found that PS/PMMA core-shell composite particles with a narrow particle size distribution and a great size would be formed when the EPC was added at the viscous energy dominated particle formation stage of St suspension polymerization with a suitable feeding rate, whereas St-MMA copolymer particles or PS/PMMA composite particles with imperfect core-shell structure would be formed when the EPC was added at the earlier or later stage of St suspension polymerization, respectively. It was also showed that the EPC composition affected the composite particles formation process. The individual latex particles would exist in the final product when the concentrations of MMA monomer, sodium dodecyl sulfate emulsifier, and potassium persulfate initiator were great in the EPC. Considering the feature of St suspension polymerization and the morphology of PS/PMMA composite particles, the formation mechanism of PS/PMMA particles with core-shell structure was proposed. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Poly(vinyl chloride)/hydrotalcite (PVC/HT) nanocomposites were prepared through vinyl chloride suspension polymerization in the presence of HT nanoparticles surface modified with alkyl phosphate (AP). The thermal stability, smoke emission and mechanical properties of PVC/HT nanocomposites were investigated. It was found that AP molecules were effectively absorbed by HT particles with no intercalation into the interlayer of HT. The dispersion morphologies of PVC/HT nanocomposites were observed by transmission electron microscopy showing that the majority of HT particles were dispersed in the PVC matrix in the nanoscale. The Congo Red measurement and thermogravimetric analysis showed that the thermal stability time, and the temperatures at 10% weight loss and at the maximum weight loss rate of PVC resins increased as the weight fraction of HT in the composite resins increased. The well-dispersed nano-sized HT showed an obvious smoke suppression effect on PVC. The maximum smoke density decreased about 1/3 and 1/2 when 2.5 wt% and 5.3 wt% nano-sized HT were incorporated into PVC, respectively. Furthermore, PVC/HT nanocomposites exhibited greater tensile strength and impact strength than the pristine PVC.

A laboratory-based surveillance network of 11 clinical virological laboratories for influenza viruses was established in Taiwan under the coordination of the Center for Disease Control and Prevention (CDC), Taiwan. From October 2000 to March 2004, 3,244 influenza viruses were isolated, including 1,969 influenza A and 1,275 influenza B viruses. The influenza infections usually occurred frequently in winter in the northern hemisphere. However, the influenza seasonality in Taiwan was not clear during the four seasons under investigation. For example, the influenza A viruses peaked during the winters of 2001, 2002, and 2003. However, some isolated peaks were also found in the summer and fall (June to November) of 2001 and 2002. An unusual peak of influenza B also occurred in the summer of 2002 (June to August). Phylogenetic analysis shows that influenza A isolates from the same year were often grouped together. However, influenza B isolates from the year 2002 clustered into different groups, and the data indicate that both B/Victoria/2/87-like and B/Yamagata/16/88-like lineages of influenza B viruses were cocirculating. Sequence comparison of epidemic strains versus vaccine strains shows that many vaccine-like Taiwanese strains were circulating at least 2 years before the vaccine strains were introduced. No clear seasonality of influenza reports in Taiwan occurred in contrast to other more continental regions.

The absorption of vinyl chloride (VC) on surface-treated light-grade and nano-scale calcium carbonate (CaCO 3 ), and VC suspension polymerization in the presence of CaCO 3 were carried out in a 5 L autoclave. It showed that the absorption of VC on CaCO 3 increased with the partial pressure of VC up to a critical point. Nano-scale CaCO 3 was more effective in absorbing VC than light-grade CaCO 3 at the same temperature and partial pressure of VC due to its greater surface area. The absorption behavior of VC/CaCO 3 follows Langmuir isothermal equation. In view of the absorption of VC on CaCO 3 , Xie’s model [J. Appl. Polym. Sci. 34 (1987) 1749] was modified to relate pressure, temperature, the amount of CaCO 3 and conversion for VC suspension polymerization in the presence of CaCO 3 . The model simulation showed that VC conversions at the pressure drop point and at a certain pressure drop decreased with the increase of the amount of added CaCO 3 , and the influence of nano-scale CaCO 3 was greater than that of light-grade CaCO 3 . The simulated VC conversions fitted well with that obtained from VC suspension polymerizations in the presence of different amounts of light-grade or nano-scale CaCO 3 .

In this paper, a molecular weight model in the vinyl chloride (VC)–divinyl monomer suspension copolymerization was derived from the mechanism of VC two-phase polymerization, with pseudokinetic constant method and the theory of the moments of chain length distribution. Furthermore, the behavior of average polymerization degree was simulated with the model at varied experimental parameters. The simulation phenomena were discussed in detail. It is concluded that our model can be useful to predict the behavior of DPw and to look inside the crosslinking mechanism in the VC–divinyl monomer copolymerization. © 1995 John Wiley & Sons, Inc.

A mathematical programming method for the analysis of the cable-stayed bridge with unilateral supports is presented. A detailed comparative study of the nonlinear phenomenon arising from the unilateral restriction at intermediate piers of the bridge is carried out. The characteristics of the unilateral supports can be described by a set of control variables which are of multi-folded constitutive relations with piecewise linearity. By using the parametric variational principle, it leads to the solution of a quadratic programming problem or to a linear complementary problem. The distinguished figures of the cable-stayed bridge with this kind of support are illustrated by numerical examples.

The vibration characteristics of offshore cylindrical tanks are studied in this paper. This is a typical topic of liquid-shell interaction system. In this paper, a general analytical method is presented by which the axial modal functions of liquid and shell are represented as the same complete orthogonal series for uncoupling the mode of liquid and shell. Simultaneously, the mode functions are expanded into a uniform convergence series and a linear polynomial, so that the problem of convergence and differentiation of mode series is solved. Therefore, the rather exact natural frequency and its corresponding mode of offshore cylindrical tank with different liquid depths, with arbitrary boundary conditions and with intermediate constraints can be obtained.

Based on analyzing the LC rear projective TV system, The OE (optical engine) for three penal LCoS rear projection TV system has been designed and modeled, The OE (optical engine) of LC rear projection display is the main component of the system, and it directly affects final performance, so the design of good color performance, high brightness and contrast and high optical efficient is the key of the system. From a commercial viewpoint, a compact size and light weight design makes it more competitive. LightTools software has a great many of powerful functions, such as modeling of optical system, analysis of illumination, modeling of machine structure, analysis of polarization and design of optical coating. We have used LightTools to analyses and optimize a whole optical engine of three penal LCoS projection display including illumination system, dividing and recombining of colors system, projection lens. At the end evaluated the performances of optical engine (parameters of output, uniformity, contract, resolution and so on).

This paper introduces the preparation of fullerence doped silica aerogels by “chemically doped” and sol gel process.The infrared spectra and time of flight mass spectra show that C60 were successfully incorporated into the silica aerogel and the structures were retained in the fabrication process.Photoluminescence spectra shows that fullerence doped silica aerogels exhibit broad visible light under Ar+ laser(488nm).The photoluminescence is blue shifted compared with pure C60.In this paper, we give an explanation to this blue shift.

In this paper, a general analytical method-space variable transform method is presented for solving free vibration problems of thick cylindrical shell with arbitrary boundary conditions. Free vibration characteristics of cantilever thick cylindrical shell are evaluated by the presented method, and the numerical results are compared with the corresponding results of thin shell theory and experimental values. Theoretical analysis and calculating results show that the method presented in this paper has good convergence and accuracy and can be extended to analyze free vibration of beams. plates and shells.

In this paper, a general analytical method based on Ref. [1] is presented to study the bending vibration of an elliptical column partially submerged in water. Besides, it is pointed out that there is a limitation to the method mentioned in Ref. [2]. As a special example, the natural frequencies of circular column submerged in water considering compressibility are calculated, and the extent of compressible effect is given.