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Rubber isolator is commonly used as vibration isolation device for piston pump, and the vibration of piston pump can be effectively reduced by adjusting the dynamic stiffness of rubber isolator. In this paper, in order to study the effect of rubber isolator's dynamic stiffness on the dynamic of seawater hydraulic piston pump (SWHPP), four kinds of rubber isolators with different dynamic stiffness were selected. An experimental modal analysis (EMA) experiment was conducted to study the influence of rubber isolator's dynamic stiffness on the natural frequency of SWHPP. The experimental results indicated that the natural frequency of the pump structure decreased as the dynamic stiffness of rubber isolator increased. Then, the influence of the rubber isolator's dynamic stiffness on the vibration of SWHPP was further studied, and conclusions can be obtained that: the vibration level of the pump decreases with the dynamic stiffness of rubber isolator increases. For the four kinds of rubber isolators, when the dynamic stiffness of rubber isolator is 5800N/cm, the vibration reduction effect of the isolator is the best, which reaching 38%. In addition, the dynamic stiffness of rubber isolator mainly affects the vibration of the pump in the frequency of 0–20 Hz.

Shuping Cao,1,* Hongxia Li,2,* Lei Li3 1Department of Gynecology, Dongying District People’s Hospital, Dongying, Shandong, People’s Republic of China; 2Department of Obstetrics, Dongying District People’s Hospital, Dongying, Shandong, People’s Republic of China; 3Department of Pathology, Dongying District People’s Hospital, Dongying, Shandong, People’s Republic of China*These authors contributed equally to this workCorrespondence: Lei LiDepartment of Pathology, Dongying District People’s Hospital, No. 333, Jinan Road, Dongying, Shandong, 257000, People’s Republic of ChinaTel/Fax +86-546-8990136Email lilei65825@163.comPurpose: Cervical cancer is a great threat to women’s health all over the world. Non-coding RNAs performed a wide range of functions. This study aimed to clarify the clinical significance and biological function of lncRNA SNHG17 and miRNA-375-3p (miR-375-3p) in cervical cancer (CC).Patients and Methods: Blood samples from 124 CC patients and 119 healthy volunteers were collected. The relative expression of SNHG17 and miR-375-3p in CC patient serums and cells was evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). The receiver operating curve (ROC) was plotted for diagnostic value estimation. The CCK-8 and transwell assay were conducted to explore the function of SNHG17 on CC cells. A luciferase reporter assay was carried out to confirm the interaction of SNHG17 and miR-375-3p. Rescue experiments were performed to verify the interaction.Results: SNHG17 showed an ascending expression while miR-375-3p descended in the serum of CC patients. For SNHG17 and miR-375-3p, respectively, the AUC was 0.863 and 0.869, the sensitivity was 84.7% and 75.8%, and the specificity was 78.2% and 86.6%. Knockdown of SNHG17 inhibited proliferation, migration, and invasion of CC cells. Serum SNHG17 expression was negatively correlated with miR-375-3p expression, and miR-375-3p was the target miRNA of SNHG17. Rescue experiments verified the knockdown of SNHG17 inhibited cell growth through repressing miR-375-3p expression.Conclusion: SNHG17 and miR-375-3p have the potential to be diagnostic markers for CC. Overexpression of SNHG17 in CC promoted the progression of CC partly via targeting miR-375-3p, implying a novel therapeutic target for CC emerging.Keywords: lncRNA SNHG17, miR-375-3p, clinical significance, biological function, cervical cancer

Water jet propulsion is a crucial technology for ships and underwater vehicles. A high-pressure water jet propulsion system was proposed in this paper. The fundamental thrust theory of this system was studied and the influence of cavitation on the thrust was investigated. First, the mathematical model of thrust based on momentum equation coupled with cavitation theory was established. Then, the performance of cavitation two-phase flow field was simulated through computational fluid dynamics (CFD), and the thrust was calculated according to these simulation results. Finally, experiments were conducted on a test rig to study its force performance. The experimental results showed that the maximum thrust reached 4000 N with a 16-mm nozzle at the flow rate of 1200 L/min. The experimental results were both higher than the simulation and the calculation results. The theoretical force model coupled with the cavitation model was better matched with the experimental results.

Few effective insulation state detection methods for power capacitor can be used in field. In this paper, a power capacitor insulation state detection method based on polarization-depolarization current is proposed. Firstly, the basic principles of the method are discussed. Then, two characterized parameters are conducted based on polarization and depolarization currents, which are DC conductivity and 0.1Hz dielectric loss. A test device based on this method is developed to evaluate the insulation state of power capacitor with different aging conditions. The test results showed that the polarization and depolarization currents increased along with the aging conditions. The DC conductance and 0.1Hz dielectric loss also increased along with the aging conditions. The test indicated the polarization-depolarization current method is suitable for power capacitor insulation state detection.

Electro-Hydraulic Proportional Directional Valve (EHPDV) is a key component in an electro-hydraulic proportional control system. Erosion-abrasion caused by solid particles within the oil is one of the major concerns in hydraulic control valves which may result in equipment malfunction and even failure. In this paper, the erosion-abrasion of a sliding spool of EHPDV was researched through Computational Fluid Dynamic (CFD) simulation and the analysis consists of three steps: the continuous phase flow field simulation, particle tracking, and erosion calculation. Therefore, a three dimensional model of the valve was built and the grid was meshed by use of ICEM. Then, a coupled Eulerian-Lagrangian approach was employed to solve the liquid-particle flow characteristics within the EHPDV, the Erosion/Corrosion Research Center (E/CRC) erosion model and the Grant empirical formula of particle-wall rebound models were utilized to predict the erosion rate. The simulation results indicated that the average erosion rate of the sliding spool would nonlinearly various with the valve opening. In addition, the maximum and average erosion rate of the sliding spool would gradually increase with the velocity. 10 µm is the critical diameter, and the erosion rate would decrease with the increases of the particle diameter if the particle diameter is above 10 µm and inversely when the diameter is below 10µm. Based on the simulation results, an erosion prediction model of sliding spool was further proposed, which provides a theoretical principle for forecasting the lifecycle of EHPDV.

Centrifugal pumps are widely used in modern industry, and blades are the key parts of it. The cracks on blades may result in a very serious consequence. In this paper, a fault diagnosis method based on principal component analysis (PCA) and Gaussian mixed model (GMM) was proposed, which combined signal processing and knowledge. Also, the theory model of proposed methods was established, and Expectation Maximization (EM) algorithm was used to make the model converge. PCA was used to reduce the data dimensionalities and increase the feature resolution, and GMM was used as classifier for crack fault. In order to verify the diagnostic effect of the model, the experimental bench of centrifugal pump was established, and various working conditions of the centrifugal pump were simulated. Experimental results showed that the classifier based on these parameters performed very well in data testing.

With the development of data science, there are more and more ways to dig for patterns hidden in the data. If we can apply the advanced model of data science to the power data, we can mine the potential value of power data. In this paper, the monitoring and inspection data of 110kV main transformers and related basic environmental data are fused to establish conditional inference tree model and AdaBoost algorithm to evaluate whether the 110kV main transformers have defects and faults. The accuracy of the two algorithms is compared. Finally, we select the AdaBoost algorithm with higher accuracy for building the 110kV main transformer fault evaluating model. This paper provides a reference for the automatic detection of power grid faults, and provides new ideas for the application of power grid big data.

Domain-specific visual language tools have become important in many domains of software engineering and end user development. However building such tools is very challenging with a need for multiple views of information and multi-user support, the ability for users to change tool diagram and meta-model specifications while in use, and a need for an open architecture for tool integration. We describe Pounamu, a meta-tool for realising such visual design environments. We describe the motivation for Pounamu, its architecture and implementation and illustrate examples of domain-specific visual language tools that we have developed with Pounamu.

According to the function and operating characteristics of water hydraulic relief valves in a high-pressure water pipe system, a novel one-stage relief valve with a one-way damper was designed and analyzed in this study. The one-way damper consists of a damping chamber and a check valve. Moreover, a damping orifice is bored along the axis of the check-valve spool. When the main spool moves to open the valve port, the check valve is fully open, and the damping orifice generates no damping force on the main spool; otherwise, the check valve is completely closed, and the damping orifice produces a damping force on the main spool. Furthermore, based on a mathematical model describing the dynamic characteristics of the relief valve, the effect of the one-way damper on the dynamic characteristics of the relief valve was simulated and analyzed, and certain optimal parameters of the one-way damper were obtained (e.g., the diameter and length of the damping orifice and the initial volume of the damping chamber). Lastly, the experimental results obtained from a prototype of the relief valve, which was manufactured to the optimal dimensions, demonstrated that the pressure overshoot was 7.5%, the response time was 1.43 × 10−2 s, and the transition time was 3.9 × 10−2 s. Thus, the one-way damper could significantly improve the dynamic characteristics of the relief valve.

A non-contact optical approach to measure the in-plane displacement of an object is introduced in this paper. Through a ste of optical system, the image of the object to be measured is formed in the image plane of the CCD. When the object moves in-plane, its image moves in the image plane of the CCD accordingly. Consequently, the displacement of the object can be detected in real-time by measuring the movement of its image with CCD. The prosed w\system is suitable for non-contact measurement such as deformation of objects in high temperature, deformation of elastic objects and low frequency mechanical vibration. It can be widely used in mechanics experiments to achieve high precision measurement in long working distance.

Here a new flash phase-shifting method has been prosed. In this method, the phase difference between three consecutive Moire images is achieved by changing the illumination angles. A theoretical derivation is presented, and certain formulas are obtained to calculate 3D information of the measured object. The special phase unwrapping algorithm connected with this phase shifting method is also solved out. At last, experiment result have been given to compare with theory derivation.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.