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his article discusses the main sources of odorants and odors in water bodies, the regulations on odorants in drinking water quality standards, and the detection of odorants in water sources and drinking water in China. Discussed two testing methods for odor substances, their respective characteristics and limitations.Introduced the treatment technologies for odorants, such as adsorption, advanced oxidation, and biological methods, as well as their respective application ranges and advantages and disadvantages. The development trend of odor treatment technology in the future was prospected. [ABSTRACT FROM AUTHOR]

Copyright of Tobacco Science & Technology is the property of Tobacco Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the analysis of operation system capability testing and evaluation, this paper studies the data resource system of operation system capability testing and evaluation from operation, business and engineering aspects. A 3-View Data resource framework is presented. And some suggestions on data resource construction are given. The research can help to clarify the data needs, improve the consistent understanding of joint operation system capability evaluation data, and promote the development of the data resource and data integrated service platform. [ABSTRACT FROM AUTHOR]

Copyright of Cancer Research on Prevention & Treatment is the property of Cancer Research on Prevention & Treatment Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Industrial Water Treatment is the property of CNOOC Tianjin Chemical Research & Design Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mechanical & Electronic Control Engineering is the property of Omniscient Pte. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Engineering Management & Technology Discussion is the property of Omniscient Pte. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Particle flow code (PFC) software has been widely used as the general discrete-element modeling (DEM), due to the excellent performance to deal with continuous and discontinuous media. Among them, the mesoscopic parameters can only be acquired to repeatedly debug the experimental data using trial-and-error method, leading to the low efficiency with the high blindness. A set of usable parameters can be inevitable in the dozens of trial and error during calibration, even though the sound experience of experts. Therefore, it is highly urgent to accurately and rapidly calibrate the mesoscopic parameters for the promotion of PFC software and the follow-up test, particularly beyond the manual operation. In this study, the uniaxial creep test model of corn stalk particles was established to combine with the built-in Burgers model of the PFC 2D. An orthogonal experiment was also carried out to verify the improved model. The multivariate analysis of variance was then made to analyze the complex relationship between the macroscopic and mesoscopic parameters of the Burgers model. There was a quite difference in the significance of the influence of each mesoscopic parameter on the macroscopic one. A highly nonlinear relationship was also found between the macroscopic and mesoscopic parameters. Therefore, the regression analysis was inappropriate to obtain the relationship between the macroscopic and mesoscopic parameters for the calibration of the mesoscopic parameters. Fortunately, BP neural network can be expected to serve as these complex relationships, just suitable for the parameter calibration. As such, the BP neural network was established with the 4, 9 and 5 nodes in the input, hidden, and output layer, respectively, according to the number and characteristics of macroscopic and mesoscopic parameters. Then, the resulting BP neural network was trained and calibrated using 150 sets of macroscopic and mesoscopic parameters. It was found that above 92% was achieved in the calibration accuracy of all mesoscopic parameters in the Burgers model, especially with the relatively stable errors. Moreover, the correlation coefficient (R) was greater than 0.96 in the trained BP neural network, indicating the more reliable performance of inversion. The improved calibration of parameters can also be popularized for the mesoscopic parameters. Furthermore, the macroscopic parameters after the uniaxial creep test of corn stalk were introduced into the trained BP neural network for the calibration of the mesoscopic parameters. A better consistence was found in the simulated and measured creep curves with the maximum error of the dependent variable of 2%, indicating the excellent calibration ability of parameters. The finding can also provide a strong reference for the PFC parameter calibration. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the problem that the response characteristics of solenoid valve for a system need to be optimized, the optimal combination of parameters affecting the response characteristics of solenoid valve was studied. Firstly, the working principle of the solenoid valve was introduced and the mathematical model of the solenoid valve was established. Then, the electric, magnetic and mechanical-hydraulic simulation model based on Simulink was established, and the orthogonal experiment method was used to optimize the response time. Four main influencing factors, including coil turns, spring stiffness, working stroke and dynamic mass, were selected for combined analysis. Finally, the optimal parameter group scheme of the main factors affecting the response characteristics of the solenoid valve was determined and analyzed and verified. The results show that the order of the factors affecting the opening characteristics is dynamic mass, spring stiffness, turns and working stroke. The primary and secondary order of factors affecting release characteristics is spring stiffness, working stroke, dynamic mass, and turns; the response characteristics under the optimal combination scheme are significantly improved compared with those before optimization. Accurate simulation results of solenoid valve response characteristics are obtained, which provides a theoretical basis for improving the design quality and efficiency of switch solenoid valve. [ABSTRACT FROM AUTHOR]

Copyright of Tobacco Science & Technology is the property of Tobacco Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Osteoporosis is the property of Chinese Journal of Osteoporosis and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Fuzhou University is the property of Journal of Fuzhou University, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A military wheel-leg hybrid quadruped robot is developed, which can move by the dynamic driving wheels on the road without being damaged at high speed, and can walk by stepping alternately in the ruins with its mechanical legs, and can skate on a flat road by the wheels without dynamic driving.The robot can walk at the maximum speed with the minimum energy consumption. A new type of meta-morphic mechanical leg based on the 3-PUPS parallel mechanism is proposed, and its kinematic analysis is done. The effects of dimension parameters of 3-PUPS mechanism on its kinematic and static evaluation indexes are analyzed by defining performance evaluation indexes. A set of the structural parameters of mechanical leg is selected, and an experimental prototype of mechanical leg is developed. A general mechanism model of wheel-leg hybrid quadruped robot is established, and the relationship among robot’s parameters and its kinematic and static evaluation indexes is revealed. A set of structural parameters of wheel-leg hybrid quadruped robot is selected,and the overall design of wheel-leg hybrid quadruped robot is completed. The pose of mechanical leg experimental prototype is measured using a special robot calibration system. Experimental results show that the maximum error of mechanical leg motion platform along x axis is 0.041 mm, the maximum error along y axis is 0.040 mm, the maximum error along z axis is 0.040 mm, the maximum error of the attitude angle around z axis is 0.041°, the maximum error of attitude angle around y axis is 0.043°, and the maximum error of attitude angle around x axis is 0.045°. The experimental prototype of mechanical leg meets the design requirements. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Clinical Hepatology / Linchuang Gandanbing Zazhi is the property of Journal of Clinical Hepatology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the continuous promotion of agricultural modernization in China, new requirements for agricultural robots are put forward. The agricultural robots are developing in the direction of automatic walking and unmanned operation, and the working environment is extended from structured environment to unstructured environment. In the future, the agricultural robots should be able to change DOF (degree of freedom) through mechanical structure changes and carry different end effectors to adapt to different types of crops, which can achieve one machine multipurpose and improve the utilization rate. In order to adapt to the new requirements of modern agriculture for robots, according to the principle of bionics, this paper presents a novel quadruped robot with 3-DOF leg mechanism based on the serial-parallel and wheel-legged mechanism, which consists of 2-universal joint-prismatic joint-spherical joint plus universal joint, and revolute joint ((2-UPS+U) &R). Firstly, based on the principle of bionics, the leg mechanism and the whole structure of the robot are developed. The walking of human and animal is realized by the contraction and relaxation of the skeletal muscle to drive the bone, and through the analysis of the distribution of muscle structure, the mechanism uses 2 electric push rods to mimic the muscle distribution of the leg to drive the swing of the robot’s upper leg in 2 directions. The mechanism has the combining advantages of series mechanism and parallel mechanism. It overcomes small work space and can achieve high precision and strong bearing capacity. The robot not only can walk in four-legged mode, but also can curl up the lower leg and become the wheeled mode to achieve rapid movement. According to the analysis of the robots with high speed and heavy load at home and abroad, the desired maximum load of the robot studied is 200 kg, the maximum speed in the legged mode is 1 m/s, and the maximum speed in the wheeled mode is 5 m/s. According to the design objective, the parameters of each part are optimized. Then the forward and inverse kinematics analysis of position for swing leg is carried out. Secondly, according to the general terrain and obstacle terrain in agriculture, the constraints for trajectory planning are put forward. Then the general trajectory planning functions of the robot’s foot-end in forward step and side step are obtained, and the obstacle negotiating trajectory of the robot foot-end is planned by spline interpolation curve, which provides the basis for robot gait planning. The obstacle trajectory planning is simulated by using the ADAMS software, results showed that the lifting height is 98.2 mm with error of 1.8 mm, and the step length is 101.3 mm with error of 1.3 mm, witch show that the robot can overcome small obstacles, and the trajectory planning is correct. The velocity and acceleration of the leg mechanism are continuous without distortion points, and the leg’s jerking movement and concussion are eliminated. All the results above show that the foot-end can achieve soft landing, and the kinematics and foot-end trajectory planning are correct. Thirdly, according to the requirement of robot gait planning, the static stability criterion and the ZMP (Zero Moment Point) theory of dynamic stability criterion are analyzed. Under the premise of ensuring the stability, the diagonal trot gait planning of robot is completed, and the fast walking of the robot is achieved. Based on the diagonal trot gait planning of the robot, the simulation is carried out. The simulation results show that the robot moves steadily and fast, with the height of the robot’s center of gravity changing only about 0.9 mm, and the gait planning is correct. Finally, the trajectory planning experiment of the robot’s single leg prototype is carried out. The leg prototype can move according to the given trajectory, and the feasibility of the mechanism design is verified. The trajectory tracking experiment shows that there are some errors between the theoretical trajectory and the actual trajectory. The maximum error of y-axis is 2.5 mm and the maximum error of z-axis is 5.3 mm, but the errors are less than 10 mm, within the allowable range of error. The errors mainly come from the manufacturing errors and assembly errors. In the future, the turn gait, pivot steering gait and climbing stair gait will be studied. The research on stability analysis and gait planning will provide a theoretical basis for establishing control system of the quadruped robot. [ABSTRACT FROM AUTHOR]

A new type of wheel-leg hybrid quadruped robot is proposed, which has four 6-DOF mechanical legs based on 3-UPS parallel mechanism. The dynamics of mechanical legs are modeled, and their driving parameters are predicted. The vector chain method is used to establish a transfer model of 3-UPS parallel mechanism, and the Jacobian matrix is established. A dynamics model of mechanical legs is established based on the Lagrange equation, and the drive force acted on the mechanism is given. The peak prediction model of servo motors for driving speed and torque is analyzed based on the dynamics model. The calculated result shows that the peak value of rotating speed of driving motor is 19.7 r/s, and the peak value of torque of driving motor is 71 mN·m. A design scheme of mechanical leg and its structure parameters are used to obtain the changes of driving speeds and torques of 6 motors over time. The calculated results show that the peak speed of driving motor is 15.3 r/s, and its peak torque is 48.1 mN·m, which are all less than the predicted limit values. The predicted peak power of servo motors is 77 (W). It proves that the dynamic analysis and the peak prediction model of driving parameters of the mechanical leg are very reasonable. [ABSTRACT FROM AUTHOR]

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chinese Mass Spectrometry Society is the property of Journal of Chinese Mass Spectrometry Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As vehicular Ad-hoc NETworks (VANET) is regarded as practical application of internet of things (IOT) in modern urban traffic network, data fusion of VANET has become an important research subject in the field of IOT information sensing. Aiming at the problems of irrational assignment of conflict evidence, bad convergence effect of fusion method and multi-BBM evidence reasoning in evidence combination of the traditional DS evidence theory, an isometric mapping evidential reasoning (IMER) method is proposed. In IMER method, the low-dimensional embedding vector of each evidence body is obtained by using the similar relations between multi-BBM evidence bodies, and then the similarity of low-dimensional evidence bodies is calculated to achieve evidential reasoning of multi-BBM evidence bodies in VANET. The experimental results show that the proposed method can reasonably assign conflict evidence and has good convergence and effectiveness. [ABSTRACT FROM AUTHOR]

Copyright of Progress in Modern Biomedicine is the property of Publishing House of Progress in Modern Biomedicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Progress in Modern Biomedicine is the property of Publishing House of Progress in Modern Biomedicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the aid of the VISAR, the velocity histories of rear free surface of the alumina with different thicknesses under plate impact loading were recorded. The failure wave trajectory was obtained from the recompression signals observed in the temporal curves of rear free surface velocity of samples. The results indicate that the generation and propagation mechanisms of failure wave are closely related to the mesoscale failure properties of alumina. The mesostructure properties of tested alumina were studied according to the SEM of alumina samples. Based on these properties, a mesoscopic model of alumina, including alumina grain phase and glassy phase, is established. Further, mesoscale simulations were presented to analyze the mesoscale failure properties of alumina. And the generation and propagation mechanisms of failure waves in shocked alumina were researched at the mesoscale. The results show that the nucleation and growth of rapid in-situ grain boundary microcracks under impact loading give rise to the failure wave phenomenon, and the failure wave propagation may be governed by diffusion processes. [ABSTRACT FROM AUTHOR]