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BACKGROUND Lumbar disc herniation is a common disease. Endoscopic treatment may have more advantages than traditional surgery. AIM To compare the clinical efficacy and safety of microendoscopic discectomy (MED) and open discectomy with lamina nucleus enucleation in the treatment of single-segment lumbar intervertebral disc herniation. METHODS Ninety-six patients who were operated at our hospital were selected for this study. Patients with single-segment lumbar disc herniation were admitted to the hospital from March 2018 to March 2019 and were randomly divided into the observation group and the control group with 48 cases in each group. The former group underwent lumbar discectomy and the latter underwent laparotomy and nucleus pulpectomy. Surgical effects were compared between the two groups. RESULTS In terms of surgical indicators, the observation group had a longer operation time, shorter postoperative bedtime and hospital stay, less intraoperative blood loss, and smaller incision length than the control group (P < 0.05). The excellent recovery rate did not differ significantly between the observation group (93.75%) and the control group (91.67%). Visual analogue scale pain scores were significantly lower in the observation group than in the control group at 1 d, 3 d, 1 mo, and 6 mo after surgery (P < 0.05). The incidence of complications was significantly lower in the observation group than in the control group (6.25% vs 22.92%, P < 0.05). CONCLUSION Both MED and open discectomy can effectively improve single-segment lumbar disc herniation, but MED is associated with less trauma, less bleeding, and a lower incidence of complications.

Aiming at the traditional optical remote sensing imaging simulation(ORSIS) method can’t meet the requirements of high resolution and precision quantitative remote sensing application, this paper pr...

Motivated by the measurements of the branching fractions of the quasi-two-body decays ${B}^{0}\ensuremath{\rightarrow}{K}^{*0}({f}_{0}(980)\ensuremath{\rightarrow}){\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ and ${B}^{0}\ensuremath{\rightarrow}{\ensuremath{\rho}}^{0}({f}_{0}(980)\ensuremath{\rightarrow}){\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$, we study the charmless $B\ensuremath{\rightarrow}V({f}_{0}(980)\ensuremath{\rightarrow}){\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ decays in the perturbative QCD approach. Supposing that ${f}_{0}(980)$ is a two-quark state and mixture of $n\overline{n}=(u\overline{u}+d\overline{d})/\sqrt{2}$ and $s\overline{s}$ with the mixing angle $\ensuremath{\theta}$, we calculate the branching fractions of these decays with the new introduced $s$-wave ${\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$-pair wave function. When the mixing angle $\ensuremath{\theta}$ lies in the range $[135\ifmmode^\circ\else\textdegree\fi{},155\ifmmode^\circ\else\textdegree\fi{}]$, the calculated branching fractions of the ${B}^{0}\ensuremath{\rightarrow}{K}^{*0}{f}_{0}(980)\ensuremath{\rightarrow}{K}^{*0}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ and ${B}^{0}\ensuremath{\rightarrow}{\ensuremath{\rho}}^{0}{f}_{0}(980)\ensuremath{\rightarrow}{\ensuremath{\rho}}^{0}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ decays are in agreement with the experimental data. The branching fractions of other decays could be measured in the current LHCb and Belle II experiments. Considering the isospin symmetry, we also estimate the branching fractions of the quasi-two-body decays $B\ensuremath{\rightarrow}V{f}_{0}(980)\ensuremath{\rightarrow}\phantom{\rule{0ex}{0ex}}V{\ensuremath{\pi}}^{0}{\ensuremath{\pi}}^{0}$, which are half of the corresponding decays $B\ensuremath{\rightarrow}V{f}_{0}(980)\ensuremath{\rightarrow}V{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$. Moreover, the direct $CP$ asymmetries of these decays are also calculated, and some of them can be tested in the current experiments.

Two new flavonoid glycosides, named viscumneoside XII (1), and viscumneoside XIII (2); a new dihydrogen flavonoid glycoside product named viscumneoside XIV (3), were isolated from the aerial part of Viscum album, along with seven known compounds (4-10). Their structures were identified by analysis of spectroscopic data. In addition, cytotoxicity assay showed that 1, 2 and 3 possessed significant inhibitory activities against C6, A549 and MDA-MB-231 (the inhibition rate arrived about 50%, 70% and 74% respectively with IC50 ≤ 60.00 μmol·L-1), while the inhibition of TF-1 and Hela was not significant.

Sugarcane bagasse was co-pyrolyzed with lignite in a fixed bed reactor to investigate the possible interaction during co-pyrolysis. GC-MS revealed that the concentration of phenols and aliphatic compounds in the tar increased with the addition of sugarcane bagasse, while the content of aromatic compounds had the contradictory tendency. The phenol content in co-pyrolyzed tar reached 20.35%, which increased by 142.26% compared with the calculated values. The sugarcane bagasse decomposition peak partly overlapped with lignite pyrolysis peak from TG-DTG curves, which meant more interaction between lignite and sugarcane bagasse during the pyrolysis process. The difference between the experimental and calculated values of pyrolysis products yield, tar components, DTG values and kinetics analysis indicated the synergetic effect between lignite and sugarcane bagasse.

Coal gas is a key factor in coal mine production safety, gas outburst and other threats can cause suffocation mine operating personnel, damage to human health, the gas reaches the ignition and combustion gases can cause encountered gas and coal dust explosion; while the main gas or the Earth's atmosphere sources of pollution. Therefore, effective governance gas to gas as a resource to achieve coal and gas extraction, to eliminate sudden end, and take advantage of the gas, reducing its air pollution is a major issue in the field of coal mining, the paper gas utilization, gas drainage aspects of mining, mine gas drainage system briefly described.

A new composite electrolyte for lithium-ion batteries (LIBS) was prepared by combining N-methyl-N-propylpyrrolidinium bis (trifluoromethanesulfonyl) imide (PYR13TFSI), N-methyl-N-pr-opylpiperidinium bis (trifluoromethanesulfonyl) imide (PP13TFSI) and lithium difluoro (oxalate) bor-ate (LiDFOB). Graphite electrode was tested in the LiDFOB-containing electrolyte, exhibiting higher reversible charge/discharge capacity and better cyclic stability. An initial charge capacity of 351.5 mAh⋅g-1 is obtained and a stable capacity of above 332.8 mAh⋅g-1 is retained after 30 cycles. The coulombic efficiency remains high above 99.3%. The outstanding cell performance was associ-ated with the formation of stable solid electrolyte interface (SEI) film on the surface of electrodes derived from LiDFOB.

N-methyl-N-allylpyrrolidinium bis (trifluoromethanesulfonyl) imide (PYR1ATFSI) with substantial supercooling behavior is synthesized to develop low temperature electrolyte for lithium-ion batteries. Additive fluoroethylene carbonate (FEC) in LiTFSI/PYR1ATFSI/EC/PC/EMC is found that it can reduce the freezing point. LiFePO4/Li coin cells with the FEC-PYR1ATFSI electrolyte exhibit good capacity retention, reversible cycling behavior at low temperatures. The good performance can be attributed to the decrease in the freezing point and the polarization of the composite electrolyte.

Introduce content and result of Study on the performance of filtration by Shangdong ceramic media ,and do comparison experiments with general quartz sand , The result shows that it is of low operation cost,high filtration efficiency and good water quality.

Mixtures of an ionic liquid (IL) with organic solvents and a lithium salt have been studied in order to develop new electrolytes for lithium-ion cells with enhanced safety profiles. In this work, N-allyl-N-methylpiperidinium bis (trifluoromethanesulfonyl) imide (PP1ATFSI) was synthesized and characterized to exhibit high decomposition temperature and wide electrochemical stability window. The evaluation of the coin cell LiFePO4/Li with the mixed electrolyte based on PP1ATFSI with 0.35mol/kg LiTFSI, and 30 wt% VC/DMC (1:1) shows a nice reversibility and cycle performances. All above prove that PP1ATFSI is one of the most promising safety electrolytes of Li-ion battery.

In this paper, we propose a microstrip fllter balun adopting double-sided parallel-strip line (DSPSL) with a conductor plane inserted in the middle of the substrate. Fed by the DSPSL at input port, two microstrip fllters on top and bottom layers are excited simultaneously, with the frequency-independent out-of-phase feature obtained between two output ports. The proposed fllter balun exhibits excellent performance with good frequency selectivity because of multiple transmission zeros generated by a new coupling scheme. Finally, a fllter balun sample is designed and fabricated, and good agreement is obtained between its measured and simulated S- parameters.

COD and BOD of the inflow of aeration basin and the effluent of secondary sedimentation tank were detected through orthogonal test.The test use removal rate of COD and BOD as evaluation index, B/C as analysis index. The result of the test indicated that the best working condition can be achieved when there are 3 water pumps for inflow, the concentration of activated sludge stands at 1600mg/L, and HRT in the aeration basin and secondary sedimentation tank stand at 1.86 hours and 2.87 hours respectively. The test demonstrated that short-time aeration can reduce the energy consumption and, therefore, the cost effectively, while insure the effluent reach the outlet qualitative standard. This is suitable for sewage treatment plants in south China since the concentration of their inflow is low.

N-methyl-N-hexadecylpyrrolidinium bromide (IL) was synthesized for the design of ionic liquid crystals which is a fascinating class of molecular materials, offering the combination of order and mobility. In binary mixtures with water, lyotropic liquid crystalline phase appears in the range of IL content from 35% to 70% and the temperature range from -1.1 to 24 °C in the heating run. The SAXS curves explored the self-assembly processes and hexagonal phase of the IL apparent sol. The saturated aliphatic ionic liquid in water assemble less tightly compared with aromatic ionic liquid based on imidazolium in water, which is due to the absence of aromatic package effect.

Several integrations of the plane wave functions frequently appearing in the scattering problems of elastic waves are considered in this study. In conjunction with the principle of superposition and the stationary wave function expansion, the exact solutions are obtained. As in the scattering problems of elastic waves and plane waves, the theoretical solutions can improve the convergence speed of the arithmetic and the computation precision. The analysis method and the analytical solutions can also be very helpful to solving other complex integrations in relation with the cylinder functions and plane functions.

Random forest has demonstrated excellent performance to deal with many problems of computer vision, such as image classification and keypoint recognition. This paper proposes an approach to classify materials, which combines random forest with MR8 filter bank. Firstly, we employ MR8 filter bank to filter the texture image. These filter responses are taken as texture feature. Secondly, Random forest grows on sub-window patches which are randomly extracted from these filter responses, then we use this trained forest to classify a given image (under unknown viewpoint and illumination) into texture classes. We carry out experiments on Columbia-Utrecht database. The experimental results show that our method successfully solves plain texture classification problem with high computational efficiency.

We propose a robust visual tracking framework based on particle filter to deal with the object appearance changes due to varying illumination, pose variantions, and occlusions. We mainly improve the observation model and re-sampling process in a particle filter. We use on-line updating appearance model, affine transformation, and M-estimation to construct an adaptive observation model. On-line updating appearance model can adapt to the changes of illumination partially. Affine transformation-based similarity measurement is introduced to tackle pose variantions, and M-estimation is used to handle the occluded object in computing observation likelihood. To take advantage of the most recent observation and produce a suboptimal Gaussian proposal distribution, we incorporate Kalman filter into a particle filter to enhance the performance of the resampling process. To estimate the posterior probability density properly with lower computational complexity, we only employ a single Kalman filter to propagate Gaussian distribution. Experimental results have demonstrated the effectiveness and robustness of the proposed algorithm by tracking visual objects in the recorded video sequences.

the radar cross section(RCS)of a target is dependent on frequency as well as observation angle. the asymptotic waveform evaluation(AWE) technique is applied to predict the mono-static RCS of an arbitrarily shaped two-dimensional cylinder in both frequency and angular domains. the method of moments was used to solve the electric field integral equation, and the surface electric current density for a single angle and frequency was obtained. In the AWE technique, the surface current on the perfect electric conductor is expanded in a rational function via the Padeapproximation. Using the function, the electric current distribution can be obtained at any angle and frequency within given angle and frequency range, which is used to compute the wide-angle and wide-band RCS. The numerical results are in good agreement with the results obtained by the method of moments at each frequency.

In this paper, a novel recognition method is proposed aiming at the current difficulties existing in Car License Plate Characters recognition. Firstly, the method builds three Template Libraries apart including Chinese characters, English letters and Figure. The character to be recognized is preprocessed involving normalization, refinement and so on. And then, it is identified by using modified Hausdorff distance template matching method. The experiments show that the method is effective and feasible.

The UMHexagonS algorithm has been accepted for the possible implementation of the block motion estimation process in the H.264 video coding standard due to its high accuracy and low computational requirement. And there were also many modifications coming up with it. In article [1], the author offered several improvements which reduce the computational complexity of the UMHexagonS algorithm with a little loss of its accuracy. And In this paper, a new algorithm is proposed, which bases on the UMHexagonS algorithm and [1] in two aspects. Firstly, a new prediction vector is added to replace the way of median vector. Secondly, we propose an Irregular-cross template in place of the primary unsymmetrical-cross one. The simulation results show that this two proposed methods reduce the motion estimation time by from 10% to 27% than UMHexagonS according to different types of sequences with negligible coding loss.

Color information carried by the matting components in spectral matting is used in our method to solve the matting problem. By comparing the color similarity of each matting component, the matting components were separated into two groups: the foreground and the background. There are two advantages of doing so. Firstly, there is no need to use the trimap which is a necessary tool in traditional matting solving methods to accomplish the process of semi-supervised learning. Instead, the color similarity information could be used as constrain or heuristic cue in finishing the process of unsupervised learning to lower the blindness of automatically extracting the foreground object. Secondly, combining the color similarity information with a little user provided foreground and background cue could further reduce the number of matting components whose group have not been known yet, and thus a semi-supervised learning process which could only be done by using a lot user provided cue in traditional matting solving methods could be accomplished.

Corner detection is a basic task in the field of image processing. This paper proposes a new corner detection method based on the curvature computing, called Curvature Statistic (CS) method. The edge points which have the maxima of absolute curvature are defined as corners, so curvature of every edge point is computed in CS. The first step is to use Canny edge detector to extract edges of original image, then compute the curvature of every edge point using a statistic method in the neighborhood. When we get the curvature of the point, we can judge whether it is a corner point or not. This method is very robust to noise. In the section of the experimental comparison we can see that CS performs good, and that most corners are detected and the localization of each corner point is more accuracy.

Given a video sequence about the road scenarios, discovering the foreground objects and labeling them are crucial. This paper proposes to represent the foreground objects in videos by the bag of words model. The foreground object is treated as a positive document which is a set of image patches, and the background region is a negative document. Initially the training image patches are sampled and represented by speeded up robust features (SURF) descriptor, and then the bag of words model is constructed by K-means clustering algorithm. Subsequently the document is represented as the histogram of the visual words which is the feature vector of the image. Finally, a naive Bayesian classifier is obtained by training these feature vectors. In the stage of foreground objects detection, the motion regions are detected firstly, and then classified by the naive Bayesian classifier. The experimental results demonstrate that the proposed algorithm is robust and efficient with the processing speed up to eighteen frames per second on a standard PC.

Object categorization has become active recently in the field of pattern recognition. There are two main factors which affect the performance of classification. One is the representation of images, and the other is the design of classifier. The representation of images based on bag-of-word(BOW) has become a popular method because of its simpleness and high efficiency. This paper aims to compare some state-of-the-art classifiers used in object categorization based on the BOW technology. In the dataset of Xerox7 and CalTech6, we compare the performance of five classifiers which are SVM, Maximum Entropy, Naive Bayes, Adaboost and Random Forests. The result of experiments show that SVM and Maximum Entropy have better performance than others.

In this paper, a novel method is presented, which detects symmetry axes for multi-object. It uses vertical line detection method in local polar coordinate. The approach costs little computation and can get efficient results, which means that it can be used in database applications.