Progressive Slide Analysis of Arch Dam Abutment

2012 ◽  
Vol 446-449 ◽  
pp. 2714-2717
Author(s):  
Ying Ming Chen

Safe analysis of the progressive slide is used to estimate the stability of arch dam. The space stochastic parameters are surveyed through considering the relativity of parameter. The stability reliability analysis can be divided into element, sub-structure or sub-system, system.etc. From element to system calculate abutment’s ability. Sub-structure is composed by elements parallel connection. System is composed by sub-structures in series. The substructure method is applied to study the interaction between arch dam and its abutment. In this paper, the weakness part of abutment was found by cracking analysis of the progressive slide, and the safe evaluation was given.

2013 ◽  
Vol 702 ◽  
pp. 3-6
Author(s):  
Ling Qiang Yang ◽  
Rui Gao

Safe analysis of the progressive slide is used to estimate the stability of arch dam. The space stochastic parameters are surveyed through considering the relativity of parameter. The stability reliability analysis can be divided into element, sub-structure or sub-system, system.etc. From element to system calculate abutment’s ability. Sub-structure is composed by elements parallel connection. System is composed by sub-structures in series. The substructure method is applied to study the interaction between arch dam and its abutment. In this paper, the weakness part of abutment was found by cracking analysis of the progressive slide, and the safe evaluation was given.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ismail Muhammad Musa ◽  
Ibrahim Yusuf

PurposeThe purpose of this paper is to model and to improve the stability and long-lasting operation of the small home solar system configuration regarding the reliability, availability, sensitivity, cost analysis and mean time to failure (MTTF).Design/methodology/approachA model of a small home solar system is designed in this write up. It is designed in a series–parallel configuration, such that four panels are arranged in parallel, working under 1-out-of-4: G; policy and two batteries configured in parallel also, working under 1-out-of-2: G; policy. The panels are connected to a charge controller, then to the batteries and lastly to an inverter, all connected together in series configuration. Different types of system reliability such as reliability, sensitivity, availability, MTTF and cost analysis for particular values of the failure and repair rates have been evaluated by using a supplementary variable and Laplace transforms and demonstrated the computed results on tables and graphs. The main objective here is to improve the stability and long-lasting operation of the small solar system configuration regarding the reliability, availability, sensitivity, cost analysis and MTTF.FindingsThe future behavior of the small solar system and similar systems can be easily predicted at any given time for any parametric values, it is also better to provide repair than replacements in the system for better availability and reliability, it signifies that γp, γb, γc and γi are responsible for the better performance of the system, the variation of sensitivity together with the parametric values variations and lastly deduced that the profit will decrease whenever service cost increase.Originality/valueThis paper provides a model of small home solar system and its reliability analysis.


Sensors ◽  
2021 ◽  
Vol 21 (8) ◽  
pp. 2838
Author(s):  
Xiaoxing Zhang ◽  
Haoyuan Yi ◽  
Junjun Liu ◽  
Qi Li ◽  
Xin Luo

There has been a rising interest in compliant legged locomotion to improve the adaptability and energy efficiency of robots. However, few approaches can be generalized to soft ground due to the lack of consideration of the ground surface. When a robot locomotes on soft ground, the elastic robot legs and compressible ground surface are connected in series. The combined compliance of the leg and surface determines the natural dynamics of the whole system and affects the stability and efficiency of the robot. This paper proposes a bio-inspired leg compliance planning and implementation method with consideration of the ground surface. The ground stiffness is estimated based on analysis of ground reaction forces in the frequency domain, and the leg compliance is actively regulated during locomotion, adapting them to achieve harmonic oscillation. The leg compliance is planned on the condition of resonant movement which agrees with natural dynamics and facilitates rhythmicity and efficiency. The proposed method has been implemented on a hydraulic quadruped robot. The simulations and experimental results verified the effectiveness of our method.


Sensors ◽  
2020 ◽  
Vol 20 (22) ◽  
pp. 6438
Author(s):  
Guangtao Lu ◽  
Xin Zhu ◽  
Tao Wang ◽  
Zhiqiang Hao ◽  
Bohai Tan

A novel piezoceramic stack-based smart aggregate (PiSSA) with piezoceramic wafers in series or parallel connection is developed to increase the efficiency and output performance over the conventional smart aggregate with only one piezoelectric patch. Due to the improvement, PiSSA is suitable for situations where the stress waves easily attenuate. In PiSSA, the piezoelectric wafers are electrically connected in series or parallel, and three types of piezoelectric wafers with different electrode patterns are designed for easy connection. Based on the theory of piezo-elasticity, a simplified one-dimensional model is derived to study the electromechanical, transmitting and sensing performance of PiSSAs with the wafers in series and parallel connection, and the model was verified by experiments. The theoretical results reveal that the first resonance frequency of PiSSAs in series and parallel decreases as the number or thickness of the PZT wafers increases, and the first electromechanical coupling factor increases firstly and then decrease gradually as the number or thickness increases. The results also show that both the first resonance frequency and the first electromechanical coupling factor of PiSSA in series and parallel change no more than 0.87% as the Young’s modulus of the epoxy increases from 0.5 to 1.5 times 3.2 GPa, which is helpful for the fabrication of PiSSAs. In addition, the displacement output of PiSSAs in parallel is about 2.18–22.49 times that in series at 1–50 kHz, while the voltage output of PiSSAs in parallel is much less than that in parallel, which indicates that PiSSA in parallel is much more suitable for working as an actuator to excite stress waves and PiSSA in series is suitable for working as a sensor to detect the waves. All the results demonstrate that the connecting type, number and thickness of the PZT wafers should be carefully selected to increase the efficiency and output of PiSSA actuators and sensors. This study contributes to providing a method to investigate the characteristics and optimize the structural parameters of the proposed PiSSAs.


Information ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 278
Author(s):  
Sanlong Jiang ◽  
Shaobo Li ◽  
Qiang Bai ◽  
Jing Yang ◽  
Yanming Miao ◽  
...  

A reasonable grasping strategy is a prerequisite for the successful grasping of a target, and it is also a basic condition for the wide application of robots. Presently, mainstream grippers on the market are divided into two-finger grippers and three-finger grippers. According to human grasping experience, the stability of three-finger grippers is much better than that of two-finger grippers. Therefore, this paper’s focus is on the three-finger grasping strategy generation method based on the DeepLab V3+ algorithm. DeepLab V3+ uses the atrous convolution kernel and the atrous spatial pyramid pooling (ASPP) architecture based on atrous convolution. The atrous convolution kernel can adjust the field-of-view of the filter layer by changing the convolution rate. In addition, ASPP can effectively capture multi-scale information, based on the parallel connection of multiple convolution rates of atrous convolutional layers, so that the model performs better on multi-scale objects. The article innovatively uses the DeepLab V3+ algorithm to generate the grasp strategy of a target and optimizes the atrous convolution parameter values of ASPP. This study used the Cornell Grasp dataset to train and verify the model. At the same time, a smaller and more complex dataset of 60 was produced according to the actual situation. Upon testing, good experimental results were obtained.


Author(s):  
V. D. Pavlov ◽  

The use of the symbolic (complex) method has significantly simplified the study of resonance and near-resonance phenomena, in particular, it has made it possible to deeply unify and formalize the consideration of various mechanical systems. The cumbersome and time-consuming operations associated with composing and solving differential equations have been replaced by simple algebraic transformations. The method is based on the mechanical analogue of Ohm’s law in a complex representation and the concept of mechanical reactance, resistance, impedance, susseptance, conductance and admittance. Resonances and antiresonances of forces and velocities are determined. Resonances occur when the elements are connected in parallel with a force source, or when the elements are connected in series with a velocity source. Antiresonances occur when a parallel connection and a speed source are combined, or a serial connection and a force source are combined. These concepts are a generalization to mechanics of the concepts of «voltage source» and «current source» from theoretical electrical engineering. The closest to the source of speed in its properties is a crank-rocker (connecting rod) mechanism with a massive flywheel. The source of force corresponds more to the rod of the significantly smaller of the two connected pneumatic cylinders.


Author(s):  
Hanno Stagge ◽  
Lars Doerrer ◽  
Ralf Benger ◽  
Beck Hans-Peter

Fuel cells consist of single cells that are connected in series to form a stack. This increases output voltage and therefore decreases current-dependent power losses, but the electric current of the stack has to flow through each single cell. In case of an increase of resistance or a failure of just one single cell the whole stack is affected. The failure tolerance of a parallel connection is higher. The serial and parallel connection of single solid oxide fuel cells (SOFC) is compared under the aspects of failure probability, power drop and stress on the single cells. With both a highly linearized and a complex SOFC model simulations have been accomplished of the connection of two single cells in parallel and in serial configuration. Additionally different connection concepts of 16 single cells were examined. Finally, an outlook on different other source or storage technologies for electric energy like batteries and photovoltaic cells is given.


2010 ◽  
Vol 43 ◽  
pp. 211-216
Author(s):  
Xiao Dong Tan ◽  
Yong Sheng Zhao ◽  
Xia Li ◽  
Bao Liang Li ◽  
Shi Xuan Yao

In this paper, a design method of software simulated SCIs has been proposed to resolve the problem that the built-in SCIs of the MCU could not meet the need of data communications in the research and development of the yacht monitoring system. Two simulated SCIs have been established through building hardware circuits and writing software programs by using the parallel I/O ports and the enhanced capture timer of the MCU. Meanwhile, the error control programs have been designed, and the reliability of the simulated SCIs has been analysed through on-site tests, in order to improve the stability of data transmissions.


Sign in / Sign up

Export Citation Format

Share Document