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This paper proposes and demonstrates a single-line discontinuous track recognition system by associating the track recognition problem of a humanoid robot with the lane detection problem. The proposal enables the robot to achieve stable running on the single-line discontinuous track. The system consists of two parts: the robot end and the graphics computing end. The robot end is responsible for collecting track information and the graphics computing end is responsible for high-performance computing. These two parts use the TCP for communication. The graphics computing side uses PolyLaneNet lane detection algorithm to train the track image captured from the first perspective of the darwin-op2 robot as the data set. In the inference, the robot end sends the collected tracking images to the graphics calculation end and uses the graphics processor to accelerate the calculation. After obtaining the motion vector, it is transmitted back to the robot end. The robot end parses the motion vector to obtain the motion information of the robot so that the robot can achieve stable running on the single-line discontinuous track. The proposed system realizes the direct recognition of the first perspective image of the robot and avoids the problems of poor stability, inability of identifying curves and discontinuous lines, and other problems in the traditional line detection method. At the same time, this system adopts the method of cooperative work between the PC side and the robot by deploying the algorithm with high computational requirements on the PC side. The data transmission is carried out by stable TCP communication, which makes it possible for the robot equipped with weak computational controllers to use deep-learning-related algorithms. It also provides ideas and solutions for deploying deep-learning-related algorithms on similar low computational robots.

Robot soccer is a classic research direction in the field of robotics. From the appearance of soccer robot, it is mainly divided into wheeled robot and humanoid robot. At present, humanoid robots and small group wheeled robots mainly compete on two-dimensional plane. Because of the small competitive dimension, the offensive and defensive tactics tend to be simple. In order to enhance the competitiveness and appreciation of humanoid. And complex motion devices based on human motion capture data (HMCD) are designed Human simulation has gradually become one of the effective means of robot design. In order to enhance the competitiveness and appreciation of humanoid, this paper innovatively designs a set of consistent kicking actions based on darwin-op2 robot, combined with HMCD method, realizes the effect of actively lobbing ball. Ideally, the robot can basically kick the ball above 35cm. Besides the robot can basically kick the ball above 30cm in practice, and the success rate is as high as 75%. It improves the competitiveness from two-dimensional to three-dimensional, which provides new ideas and schemes for attack and defense tactics and expands the dimension of competition. It also provides a new direction for the development of humanoid robot football in the future.

Hatchery release of silver carp (Hypophthalmichthys molitrix) is an efficient strategy that has been carried out for years, and its scales expand year by year in the lower reaches of the Yangtze River (LRYR) in China. As the cultured juveniles are released into self-recruiting wild population to increase fisheries resources yields, they may potentially come along with negative impacts such as intra-inter specific completion, loss of genetic diversity and fitness, even causing genetic risk. To assess the relationship between genetic risk and stock enhancement (SE) of the silver carp in the Yangtze River (YR); microsatellite loci amplification, parentage assignment, genetic diversity, genetic differentiation and structure were conducted and testified by the help of eleven fluorescence-labeled microsatellite markers method. Results showed that silver carp populations in the YR had relatively higher genetic diversity (UHe), inbreeding coefficient (Fis), and effective population size (Ne) than breeding stock populations from eight hatcheries. By using the analysis of molecular variance (AMOVA), results showed that the percentage of variance among populations and within populations were 4.15 % and 95.85 %, respectively, which indicated that genetic structure of YR populations possibly had been changed by SE. Therefore, the present study suggests that the large-scale SE possibly resulted in negative genetic impact on silver carp population. Most importantly, an evaluation system in fisheries resource recruitment and genetic risks was established for SE and management.

Through combining the soft set with KU-algebras, this paper introduces the concept of a new type soft prime ideal of KU-algebras and investigates its properties. Firstly, we give the equivalent descriptions of the new type prime soft ideal of KU-algebras. Then, we show the differences between the new type soft prime ideal of KU-algebras and the common soft prime ideal of KU-algebras by giving examples. After then, studies about the equivalent description of the new type soft prime ideal and the new type soft ideal prove that the algebraic structure of dual soft set is different from the algebraic structure of \(\alpha \)-level set. Besides, we define the new concept of the projection of AND operation of soft set, and the obtain that the projection of AND operation of two soft set is also the new type soft prime ideal, if the AND operation is a new type soft prime ideal of KU-algebras. Finally, we explore the properties of the new type soft prime ideal of KU-algebras about the image and inverse image.

Selaginella tamariscina is a typical resuscitation medicinal plant with extreme drought tolerance. Trehalose plays an important role in the resurrection process, and the trehalose-6-phosphate synthase(TPS) is the key enzyme to synthesize trehalose in plants. In this study, the sequence of TPS was obtained by splicing from the transcriptome data of S. tamariscina. After the synthesis of cDNA based on the template of total RNA, the sequence was cloned by RT-PCR for verification and then analyzed by bioinformatics methods. The results indicated that the full-length coding sequence of StTPS was 2 799 bp (GenBank accession no. MH155231), and the encoded protein contained 932 amino acids. StTPS could be located in the chloroplastid according to subcellular localization prediction. There were two conserved domains belonging to glycogen phosphorylase glycosyltransferase (GPGTF) family but no signal peptide or transmembrane domain in StTPS. The expression of StTPS was determined by qRT-PCR and the variation of trehalose content was measured by HPLC-ELSD during the resurrection process of S. tamariscina. Meanwhile, the correlation between them was analyzed. The results showed that both the expression level of StTPS and the trehalose content increased associated with the extension of dehydration time, and declined associated with the extension of rehydration time which proved a significant positive correlation between the StTPS expression level and the trehalose content. The results suggested that the StTPS probably plays a central role in recovery process in S. tamariscina.

Squalene synthase of Alisma orientale catalyzes farnesyl diphosphate (FPP) to form squalene, which is the key regulatory enzyme of the carbon source flow to protostane triterpenes biosynthesis. For further research on the function and expression of AoSS gene, the open reading frame (ORF) of squalene synthase gene (accession no. JX866770) from A. orientale was subcloned into a prokaryotic expression vector pCzn1 and induced the expression of AoSS gene in Escherichia coli BL21(Roseta). The fusion protein was mainly in the form of inclusion bodies and purified to obtain high purity protein. By verifying its functionality through vitro enzymatic reaction, the results showed that the catalytic protein had the catalytic activity of FPP into squalene. In order to research the expression of AoSS in A. orientale, the purified protein was used to immunized rabbits to prepare polyclonal antibody which was then purified, the titer of the antibody was greater than 1∶51 200 by ELISA detection, and displayed good specificity by Western blotting. The prepared antibody was used for immunoassay of AoSS in different organs of A. orientale, and the results showed that the AoSS expression level was the highest in tubers, followed by leaves, and lowest in root. Successful construction of prokaryotic expression vector, validation of gene functions and establishment of rapid immunoassay lay the foundation for further researches on the function and regulation of AoSS gene, and also provide scientific basis on the application of the protostane triterpenes of A. orientale in the field of synthetic biology.

Ion Mobility Spectrometer (IMS) is an effective instrument for detecting narcotics and explosives. Signal average IMS (SA-IMS) is used widely because it is relatively convenient to build. SA-IMS is low efficient in utilization of sample ions (1%), while FT-IMS is relatively high (25%). However, detailed discussions of several important parameters, such as frequency sweeping range, frequency sweeping intervals and gating function distortion, have not been made in previous studies. In this article, we build a numerical simulation model of FT-IMS, with which we appraised these parameters respectively. Main job of this article is done with MATLAB. We also propose several guidelines in building FT-IMS.

Air core transformer is an essential part of mass spectrometer. Test coil is often used to measure its resonant frequency with the advantages of easy installation and high sensitivity. However, the influence of test coil while it is installed close to the working coils on the transformer is not studied before. To reveal the influence of test coil and determine the right position to install, two experiments using test coil and opened probe respectively for the measurement are conducted. Since the opened probe has little load effect on the original transformer impedance system, it can be used to validate the influence of test coil. By comparing the two experimental results, we find that the right position to install the test coil is on the further side of the primary coil to the secondary coil. This work allows us to integrate the test coil with the air core transformer to monitor the resonant frequency in real-time.

The bubbles in the microfluidic based electro-spray ionizing chips seriously affect the performance of the system. This paper presents a bubble capture method to stabilize the current of the microfluidic based electro-spray ionizing sources. A bubble capture structure was introduced to collect the bubbles. A normal close clamp valve assured a suitable pressure in the bubble capture structure that no liquid in the microfluidic channel can enter; when the bubble capture structure was filled with gas bubbles, the clamp valve was opened to release the bubble and balance the pressure. The results indicated that the current fluctuation, which reflects the stability of the electro-spray ionizing devices, was below 1.8% during the stable cone-jet electro-spray stage (2000V~4500V) for the proposed system, which was a notable improvement comparing with normal microfluidic-based electro-spray ionizing chip without the bubble capture structure.

Over the last decade, a relatively in-depth research on the different structures and types of the full SiC pressure sensors including the piezoresistive, the capacitive and the optical SiC pressure sensors etc. has been conducted with a view to realizing the pressure measurement in high temperature circumstances. The piezoresistive SiC pressure sensor has gradually become the focus of research due to its simple structure and convenience application. In our research, the piezoresistance strip is designed on the deep-etching sensitive circular diaphragm formed via deep etching. Firstly, the 6H-SiC strain coefficient GF value is compared on the radial direction and the transverse direction by analyzing the circular diaphragm deformation theory. It’s concluded that both in the radial direction, four resistance strips are assigned in the center of circular diaphragm and along the edge respectively, with equal number on these two locations. Better consistency and sensitivity are achieved by this solution. Secondly, the design size of the sensitive circular diaphragm and the pressure resistance strips are determined with the expected work temperature and the target measuring range being taken into consideration. The final layout scheme design of four pressure resistance strips is determined through simulation on the consideration of the thermal stress caused by the AlN packaging.

The liquid floating rotor gyro is a gyroscope using electrostatic or electromagnetic forces to levitate rotor, and filling rotor-stator cavities with liquid in order to improve stability of motion. Under influence of the relative surface roughness, rotor velocity, dimension of flow field and fluid nature, flow characteristics of cavity flow field vary under different boundary conditions and geometrical conditions. This paper adopts three-dimensional model and periodic boundary conditions to conduct numerical modeling on cavity flow field. Its results show that, with velocity rising, distribution of flow field speed and pressure manifests partial fluctuations in turbulent-flow-intensive area; resistance torque amid rotor rotation is nonlinearly correlated with velocity, whose rules can be obtained through high-order curve fitting.

on beam assisted deposition (IBAD) is an important technique to fabricate the second generation high temperature superconducting (2G HTS) wires. Among the fabrication routes of 2G HTS long wires, IBAD route achieved the best performance in recent years. IBAD was adopted in this field in 1991 to obtain biaxially textured buffer layers, which helped to deposit high quality YBCO superconducting films on metallic substrates for the first time. Series of experimental and industrial researches on IBAD were carried out by many groups worldwide. And in the researches lasting for over two decades, the focused material for IBAD was changed from Yttria-Stabilized Zirconia (YSZ), Gd2Zr2O7 (GZO) to MgO. In this paper, the research progresses and the main achievements were briefly reviewed.

A novel ball-end mill manufacturing algorithm of 5-Axis CNC Machining grinder and the simulation test of the algorithm based on a CAD system are presented in this paper. In order to obtain an accurate algorithm of a ball end mill machining, a mathematical model is needed so that the shape of the mill can be parameterized. Therefore, the mathematical model can be adjusted based on that model. Each of the processing parts has its own position in the local coordinates system. Then, with the coordinates determined by the mathematical model, the partial coordinate and the relative movement between the grinding wheel and the barstock in the local coordinates system can be calculated. So that the 5-Axis manufacturing coordinate can be confirmed by the partial coordinate and the structural parameter. If we input these data and make the 3D-CAD simulation before the machinery manufacture, the algorithm can be tested effectively.

Mass spectrometer is one of the most versatile tools in current analytical science, which can perform both qualitative and quantitative chemical identification with high sensitivity, high accuracy and low consumption. Currently, the development of miniature mass spectrometer has received growing interest, since it provides a rapid way for online detection and real-time analysis. Quadrupole analyzer has been widely used in quantitative analysis, and it can be easily miniaturized for the purpose of developing portable mass spectrometers. A portable quadrupole mass spectrometer was developed for in-situ analysis, which can perform both qualitative and quantitative analysis for solid or liquid samples in atmospheric conditions.

Corner radius end mill, whose cutting capability is mostly affected by the relief surface, is a kind of highly effective end mill [1]. So a novel mathematical model of relief surface curve about corner radius end mill, which is verified with a five-axis computer numerical control (CNC) grinding machine and simulated based on a system CAM, is derived and presented in the paper. According to the proposed tool coordinates system and the mechanical coordinate of the machine, the relative motion between the cup wheel and the tool is determined. In order to obtain an accurate relief curve when machining, the model of a cup wheel edge is also introduced. The coordinates of grinding point when grinding relief surface are calculated. With the input data of the corner radius end geometry, wheels geometry, wheel setting and machine setting, the NC code is generated automatically from the program. Then the code is used to simulate in 3 Dimension before actual machining. Finally, the NC code will be used for machining in the CNC grinding machine. The roundness of the round corner in the final product is very well, means this model is effective.

A novel algorithm for the ball-end mill relief using a five-axis computer numerical control (CNC) grinding machine and the simulation of the ball-end mill based on a CAM system is presented in this paper. In this study, In order to obtain an accurate normal relief angle, which is one of the key factors affecting tool cutting performance, a tool coordinate system based on the required relief angle and the cutting edge was established. Then, by the proposed tool coordinate system, an algorithm to determine the position between the grinding wheel and the tool is proposed, and then the relevant formulations are deduced. The coordinates of grinding point when the step of relief surface is grinded are calculated.Using the input data of a ball-end mill geometry, wheels geometry, wheel setting and machine setting, the NC code for machining will be generated. Then the code will be used as input to simulate the ball-end mill machining in 3 Dimension before real machining. The algorithm of ball-end mill relief can be authenticated by the 3D simulation system.

A new discharge system which can generate stable atmospheric pressure DC glow discharge is reported in this paper. The system is made up of an inner line electrode and an outer cylinder-like electrode. The radii of the inner and outer electrodes are only 0.08 and 2 mm, respectively. The transition from corona discharge to glow discharge is observed. The experiments show that the discharge has typical features of normal glow discharge and can produce nonthermal plasma. It has been used as an ambient ion source, and chemicals such as formic acid, acetic acid, phenol, and benzoic acid can be ionized well.

Travelling wave wall used for Micro Air Vehicle flow control is studied to find out its drag reduction effect. Aerodynamic characteristics of the airfoil with and without a streamwise travelling wave on its surface are calculated. The interrelationship is also analyzed among lift, drag and ratio of motion phase speed to the external flow velocity. The flexible airfoil that can generate streamwise travelling waves is realized via electromagnetic coil actuation. Thirty-six coils are placed streamwisely under heat shrink film and magnets producing magnetic field are placed under coils. Every single coil is controlled by current to move vertically in harmonic motion with 30 degrees phase difference between adjacent ones. So heat shrink film is actuated, and streamwise travelling wave is generated. Meanwhile, a prototype is designed and tested in wind tunnel. The experimental aerodynamic data proves that streamwise traveling wave airfoil can increase lift and reduce air drag.

To facilitate the manufacturing of an end mill, this paper presents a manufacturing model of a flat-end mill using a five-axis computer numerical control (CNC) grinding machine. Using input data of end mill geometry, wheels geometry, wheel setting and machine setting, the NC code for machining will be generated directly from a solid modeling then used as input to simulate the end mill machining in 3 Dimension before machining. The 3D simulation system of the end mill grinding is generated by VBA and AutoCAD2008. Machining simulation consists of a sequence of Boolean operations on difference between the tool and the grinding wheels through NC code. Then the major design parameters of a cutter, such as relief angle and inner radius, can be verified by interrogating the section profile of its solid model. The manufacturing model presented in this paper provides a practical and efficient method for developing CAM software for the manufacture of an end mill.

A novel ambient glow discharge ion source with improved line-cylinder electrodes is put forward and designed in this paper. The diameters of inner and outer electrodes are 0.16 and 4 mm respectively. With a special assembly method, a perfect coaxiality of the two electrodes is obtained. From the gas discharge experiment, it can be seen that the discharge can stably work in normal glow discharge mode. The operating currents of the ion source are in an order of milliamperes and can generate a much larger number and wider variety of reagent ions. The MS experiment shows that the ion source has higher detection sensitivity.

This article investigated the dispersion and modification of multiwalled carbon nanotubes (MWCNTs) through solution mixing based on the noncovalent interactions between polystyrene (PS) and MWCNTs. It was found that the interactions were robust enough to stabilize the debundled MWCNTs in solution after vigorous sonication. The PS attached, which altered the surface properties of MWCNTs and made them easily soluble in organic solvents, can remain even after careful washing with solvents. Besides, many other PS-based polymers were proved to retain the ability to disperse MWCNTs to form stable solutions. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

The barium titanate based X7R ceramics, which are doped with rare earth oxide, Nb2O5, Co3O4 and ZnO-B2O3, could be sintered at a rather low temperature to satisfy the X7R requirements with good permittivity and dielectric loss. In this paper, different doping methods of sintering aids have been used to prepare X7R BaTiO3 ceramics. Samples were sintered at a low temperature and the relationship of doping methods and sintering properties has been concluded.

Incorporation of carbon nanotubes (CNTs) into such functional devices as transistors, sensors and field emitters requires a control over their placement on substrate surfaces. In this paper, horizontal arrays of multi-walled carbon nanotubes (MWNTs) have been assembled on silicon substrate surfaces using a gas flow method. The influences of the flow rate and the flow time on the alignment of the MWNTs have been systematically studied. Additionally, the field emission property of the horizontal MWNT arrays prepared using this method has been studied.

To study the protective effect of glucagon-like peptide-1 (GLP-1) on the left ventricular diastolic function and endothelial function in patients with type 2 diabetes.27 patients with type 2 diabetes were randomly divided into two groups: GLP-1 treated group and insulin treated group. Patients in the GLP-1 group were given GLP-1 analogue and metformin hydrochloride. Patients in the insulin group were given insulin and metformin hydrochloride. The outcomes of treatments were measured by fasting plasma glucose (FBG) fasting lipid profile, glycosylated hemoglobin (HbA1c), blood pressure and general clinical features. High resolution Doppler ultrasound was performed to detect mitral early diastolic rapid filling (E-wave), atrial contraction late filling (A-wave), E/A ratio, early diastolic mitral annular velocity (e), late diastolic mitral annular velocity (a), e/a ratio, endothelium-dependent vasodilatation (EDV) mediated by brachial arterial blood flow, and endothelium-independent vasodilatation (EIV) mediated by nitroglycerin.The levels of FBG and HbA1c decreased significantly in both groups after treatments (P0.05). Patients in the GLP-1 group showed improved e, e/a ratio, and E/e ratio after treatments (P0.05), but no significant changed in E, A, and E/A ratio (P0.05). By contrast, patients in the insulin group showed no significant changes in e, a, E, A, E/A ratio, e/a ratio and E/e ratio after treatments (P0.05). EDV increased significantly after treatments in both groups (P0.05). A higher level of post-treatment EDV was found in patients in the GLP-1 group compared with those in the insulin group. No significant changes in EIV were found in both groups.GLP-1 may be able to mitigate the left ventricular diastolic dysfunction and improve endothelial function of patients with type 2 diabetes. Our findings suggest that GLP-1 has the potential to prevent or delay cardiovascular complications in patients with type 2 diabetes. Further studies are needed.

Controlling the length of carbon nanotubes (CNTs) by easy and reproducible method has proven to be crucial for most devices based on CNTs and solution-phase processing of CNTs. In our previous study, it was confirmed that controlling the length of the multi-walled carbon nanotubes (MWCNTs) could improve the probability in the post-growth assembly of MWCNTs [1]. Many studies have been done on length sorting of the cut CNTs. The methods include field-flow fractionation (FFF) [2], capillary electrophoresis (CE) [3,4], gel electrophoresis [5], size-exclusion chromatography (SEC) [6–9], and high performance liquid chromatography [10]. These approaches are usually applicable for short single-walled carbon nanotubes (SWCNTs), and the sorted CNTs are functionalized with polymer or surfactants. In addition, the lengths of the SWCNTs are usually several hundred to tens of nanometers. In this study, we report a method specially focusing on length sorting of the MWCNTs. Firstly, the long and bundled pristine MWCNTs are oxidatively shortened, and dispersed in water with broad length distribution. Then through high-speed centrifugation with changing speeds, the MWCNTs are sorted from over ten microns to hundreds of nanometers with narrow length distribution without using any surfactant or polymer. Oxidized MWCNTs (0.5 g) were dispersed in 1000 ml water by sonication for half an hour before putting it in the high-speed centrifugal machine (Hitachi Himac CR 21G) for length sorting. The process began with 4000 rev for 1 h until the sediment was formed, which was collected and named M-1. Then the residual solution was continued to be centrifuged under 6000 rev, 8000 rev and 10,000 rev for 1 h, respectively. The sediments obtained at various rotating speeds are called M-2, M-3, M-4, and the last residual solution is called M-5. Furthermore, the sediments of M-1 to M-4 were dispersed in water, respectively by sonication and centrifuged again under 4000 rev, 6000 rev, 8000 rev and 10,000 rev for 1 h. The collected sediments and residual solutions are called M-1-1 and M-1-2, M-2-1 and M-2-2, M-3-1and M-3-2, M-4-1 and M-4-2, respectively. The scheme of the whole process is shown in Fig. 1. As shown in Fig. 1, the sedimentated MWCNTs (M-1-1) was first obtained at low centrifugal speed. With increasing the speed, the M-5 was lastly obtained at the highest centrifugal speed. Every fraction of the MWCNTs was dispersed in water to form very dilute solution and further sonicated for 30 min. Then a drop of the solution was dripped onto a 3m m· 3m m NH 2–silicon wafer functionalized with NH2 groups, and the MWCNTs adsorbed on the silicon wafer were observed by scanning electron microscopy (SEM, Hitachi S-4550) after drying. As shown in Fig. 2, the first fraction (M-1-1) is mainly consisted of long and wide nanotubes, which have the average length of 4.26 lm, and some MWCNTs are above 10 lm. The second fraction (M-1-2) is found to be consisted of shorter nanotubes (average length of 2.33 lm). The tube lengths decrease gradually with increasing the centrifugal speed. The average lengths of the MWCNTs in the later fractions (M-2-1 to M-5 ) are 1.7 lm, 1.4 lm, 0.96 lm, 0.90 lm, 0.81 lm, 0.69 lm, and 0.53 lm, respectively. In the last fraction, it is found that the lengths are mainly less than 500 nm. The average lengths for different fractions are shown in Fig. 3, which are getting shorter and shorter with increasing the centrifugal speed, and 1–9 represent M-1-1, M-12, M-2-1, M-2-2, M-3-1, M-3-2, M-4-1, M-4-2, M-5, respectively in the histograms. The defects of the MWCNTs were characterized by Raman spectra (Nicolet Almega dispersive Raman spectrometer with a 514 nm excitation source). Five samples, M-1-1, M-2-1, M-3-1, M-4-1 and M-5 were chosen for analyzing. The ratios of the G band to the D band, which are attributed to ordered graphitic structure and the defects of the CNTs, respectively, are 1.24, 1.21, 1.16, 1.14, and 1.00, respectively, and the ratio of the pristine MWCNTs

This paper presents the development of an electrically powered micro air vehicle (MAV) with a wingspan of 360 mm. A miniature flight control system including a self-made micro video image system especially suitable for MAV is developed. The aerodynamic performance of several airfoil sections at low chords Reynolds number is analyzed in order to find an optimum airfoil section for the MAV prototype. A small-sized propulsion testing setup is built to measure the performance of the motor-gear-propeller-battery combination so that an efficient propulsion system can be obtained. The TH360 MAV with a payload of a self-made micro color video image system has been successfully tested in the real-time flight, where the real-time images of the ground target can be transmitted from the onboard video camera to the ground.