Paradigm for Determining the Optimal Ultradeep and Superthick Saline Aquifer for High-TDS Mine Water Geological Storage

Saline aquifers are the most popular waste and CO_(2)injection and storage reservoirs worldwide.This project proposes that several optimal injection positions should be investigated as hydraulic pressure-focused positions,in order to relieve the high demands of pump performance.The comprehensive indices(F_(i))representing the injectivity of different burial depths were obtained by using information entropy,based on the mercury injection experimental data of 13 rock samples.The results demonstrated that the burial depths of No.4,No.1 and No.2 in the Liujiagou Formation were the most suitable positions for hydraulic focused injection,which means the upper 30 m thickness could be regarded as the hydraulic focused range in the saline aquifer with an average thickness of 400 m.In addition,some laboratory experiments and in situ tests were carried out for the purpose of certifying and analyzing results,including SEM,XRD,brittleness index and logging.The results suggested that the rock samples at the No.4,No.1 and No.2 burial depth ranges have loose microstructure,weak cementation,as well as dual pores and fractures.The lithology is mainly quartz and feldspar,but the clay mineral content is high(10%-25%),which is positive for dissolution.The lithology is suitable for hydraulic fracturing to form extended cracks and micro-fissures during high-TDS(total dissolved solids)mine water injection,because of the high brittleness index.Finally,a theoretical and technical framework for high-TDS mine water injection was established,based on operating pilot engineering.Some theoretical defects and drawbacks learned from the field practices were summarized and solutions proposed.The research in this study could provide guidance and a paradigm for the inexpensive treatment of high-TDS mine water by injection and storage.

Determination of Optimal Cash Position of Mutual Fund

Cash position, held by mutual fund with purpose to satisfy investors′ redemption, will inevitably generate certain amount of cost. In this paper, the total cost caused by cash position is divided into opportunity cost and shortage cost, and a model is constructed to describe the relationship between total cost and cash position along with investors′ purchase and redemption, from which the formula of optimal cash position is deduced. Finally, the adjustment of optimal cash position in different market situations is discussed.

Position Optimization for Mobile Relay Communications with Constrained Energy over a Whole Horizontal Plane

This paper concerns the position optimization problem of a mobile relay over a whole horizontal plane.This problem is important because the position of a mobile relay directly affects the end-to-end performance,e.g.,reliability,connectivity,and data rate.In this paper,we propose a new position optimization scheme of a mobile relay over a whole horizontal plane based on the one-bit feedback information from the destination node,which improves the performance over the prior scheme whose position of the mobile relay is optimized over a fixed orbit.In the proposed scheme,the mobile relay is equipped with merely one single onboard antenna.Moreover,no prior information about the positions of both the source node and the destination node is required.Thus,the proposed scheme can work at low network resources scenario,which is particularly suitable for mobile relay communication with constrained energy,e.g.,the communications in a disaster area where the infrastructure is heavily damaged,volcano monitoring,and wireless powered communication networking.According to the characteristics of the proposed scheme,we further design two heuristic implementations to calculate the optimal position of a mobile relay over a whole horizontal plane.The first implementation has better steady performance whereas the second implementation has better convergence speed.We implement the proposed scheme and conduct an extensive performance comparison between the proposed scheme and prior schemes to verify the advantages of the proposed scheme.

The Topology Optimization of Oil Cylinder Mounting

The method of the structural topology optimization is often used to design machine in the early stage of the mechanical design.And the mechanical structures use the topology design to produce a new still and lightweight part with the different loading.A new structure is created through overlapping these new optimized structure.

2(1/2)D(FD)~2TD Method and Its Application to an Antenna in Water

A novel 212DFDTD method aiming to deal with dispersive media is developed. It is named as 212D(FD)2TD method. The main idea of it is to represent the constitutive equation by a convolution in time domain. Consequently, this newly developed method is used to analyze some of the characteristics of an ideal line antenna in pure water. A good agreement with the former experimented results is obtained.

Experimental Investigation and Optimization Design of Multi-Support Pipeline System

The design of aircraft hydraulic pipeline system is limited by many factors,such as the integrity of aviation structure or narrow installation space,so the limited clamp support position should be considered.This paper studied the frequency adjustment and dynamic responses reduction of the multi-support pipeline system through experiment and numerical simulation.To avoid the resonance of pipeline system,we proposed two different optimization programs,one was to avoid aero-engine working range,and another was to avoid aircraft hydraulic pump pulsation range.An optimization method was introduced in this paper to obtain the optimal clamp position.The experiments were introduced to validate the optimization results,and the theoretical optimization results can agree well with the test.With regard to avoiding the aero-engine vibration frequency,the test results revealed that the first natural frequency was far from the aero-engine vibration frequency.And the dynamic frequency sweep results showed that no resonance occurred on the pipeline in the engine vibration frequency range after optimization.Additionally,with regard to avoiding the pump vibration frequency,the test results revealed that natural frequencies have been adjusted and far from the pump vibration frequency.And the dynamic frequency sweep results showed that pipeline under optimal clamp position cannot lead to resonance.The sensitivity analysis results revealed the changing relationships between different clamp position and natural frequency.This study can provide helpful guidance on the analysis and design of practical aircraft pipeline.

The possibility of isolated target 3-D position estimation and optimal receiver position determination in SS-BSAR

Starting from the generalized ambiguity function of bistatic SAR （BSAR）, it is shown that 3-D point target estimation can be carried out in space-surface bistatic SAR （SS-BSAR）. Appropriate analytical equations, based on maximum likelihood estimation （MLE）, are derived and confirmed via computer simulation. Furthermore, the performance of the estimate using the Crammer-Rao bound is analyzed for the case in question, thus further revealing the possibility and potential of target 3-D position estimation. Setting the determinant maximum of the information matrix as the criterion, the optimal receiver position and multi-receiver configuration are analytically determined in the SS-BSAR system. Simulation results also validate the correctness of the analytical calculation.

Joint remote preparation of an arbitrary five-qubit Brown state via non-maximally entangled channels

We firstly present a novel scheme for deterministic joint remote state preparation of an arbitrary five-qubit Brown state using four Greenberg-Horme-Zeilinger （GHZ） entangled states as the quantum channel. The success probability of this scheme is up to 1, which is superior to the existing ones. Moreover, the scheme is extended to the generalized case where three-qubit and four-qubit non-maximally entangled states are taken as the quantum channel. We simultaneously employ two common methods to reconstruct the desired state. By comparing these two methods, we draw a conclusion that the first is superior to the second-optimal positive operator-valued measure only taking into account the number of auxiliary particles and the success probability.

Research on controlling long-term performance by tensioning post tendon of long-span continuous rigid-frame bridges

The problems like cracking of the girder in the mid-span and the ever-increasing vertical deflection appear during the long term usage of the long-span continuous rigid-flame bridge. Post-tension tendon with re- served duct can increase the pre-stress of the main beam effectively, and decrease the long term span deflection in order to improve the performance of the girder. At the same time, the proper tension position is very crucial to optimise the stress distribution of the bridge and control the deflection increase. Combining with practical en- gineering, the authors analyze the influence of different positions of post-tension tendon （ including top-, web- and bottom plate tendons） on the stress and deflection of the main beam, and find out the optimal position of post tendon.

Optimization of the key position parameters for tractor steering wheel based on a driver’s arm muscle load analysis

Steering wheel is the most frequently used manual device in tractors,whose position directly affects the handling comfort of the driver and fatigue degree of the arm muscles.In this study,the biomechanical modelling software AnyBody was used for an inverse kinetics analysis of the rotation process of tractor steering wheel,calculate the muscle activation degree of the driver’s arm and compare it with the calculated results of surface EMG tests to verify the reliability of the biomechanical model.Based on the biomechanical model,the effects of three position parameters(steering wheel inclination,front-back distance,and upper-lower height)on the activation degree of the driver’s arm muscles were evaluated.The results demonstrated that steering wheel inclination has the most significant effect on the degree of muscle activation,followed by the upper-lower height and then front-back distance.Considering the interaction among factors,a regression orthogonal test was designed,and the test results revealed that the minimum muscle activation(1.2887)can be obtained with the steering wheel inclination of 31°,front-back distance of 431 mm and upper-lower height of 375 mm.The findings can provide a reference for optimizing the structure and position parameters of tractor steering wheels.

Comfort evaluation and position parameter optimization of the steering wheel in agricultural machinery based on a three-level evaluation index system

The aim of this study is to evaluate the comfort and optimize the position parameters of steering wheel.Taking the H point of driver as the reference point,three position parameters of steering wheel were determined,which were used as experimental factors.A comprehensive evaluation index system of the comfort was established.The comfort range and optimal levels of three parameters were determined by a single factor test,based on which a response surface optimization and validation test was carried out.The optimization and validation test results show that the expected comprehensive score of the comfort is 0.864,and the average relative error between the predicted and the measured value is 4.18%,indicating that the optimization results are reliable.The findings can provide reference for the comfort optimization design of steering wheel in agricultural devices.

Position optimization of particular solution sources for distributed source boundary point method by volume velocity-matching

Choosing particular solution source and its position have great influence on accu- racy of sound field prediction in distributed source boundary point method. An optimization method for determining the position of particular solution sources is proposed to get high accu- racy prediction result. In this method, tripole is chosen as the particular solution. The upper limit frequency of calculation is predicted by setting 1% volume velocity relative error limit using vibration velocity of structure surface. Then, the optimal position of particular solution sources, in which the relative error of volume velocity is minimum, is determined within the range of upper limit frequency by searching algorithm using volume velocity matching. The transfer matrix between pressure and surface volume velocity is constructed in the optimal position. After that, the sound radiation of structure is calculated by the matrix. The results of numerical simulation show that the calculation error is significantly reduced by the proposed method. When there are vibration velocity measurement errors, the calculation errors can be controlled within 5% by the method.

Active vibration control of a large space telescope truss based on unilateral saturated cable actuators

Due to obvious advantages,such as light weight,easy folding and deployment and high accuracy of optical imaging,the membrane diffraction large space telescope has currently been one of the hot research topics.Because of the influence of external disturbance and attitude adjustment,the large space telescope will occur a certain degree of vibration inevitably,affecting the imaging accuracy of the space telescope for Earth.Thus,to satisfy the requirement of imaging accuracy,it is necessary for the space telescope to adopt appropriate vibration control methods.In this paper,the active vibration control of the large space telescope is studied using cables as active actuators.Considering that cables can work under tension but not under pression and the tensile capacity is limited,the unilateral and saturated characteristics of cable actuators are taken into account during control design in this paper.Firstly,the dynamic model of the membrane diffraction space telescope is established using the finite element method(FEM).Secondly,in combination with the linear quadratic regulator(LQR)and the bang-bang regulator,a piecewise cost function is used to design the active vibration control law.Next,the controllability criterion and the genetic algorithm(GA)are adopted to determine the optimal positions of cable actuators.Finally,the validity of the proposed control method is verified by numerical simulations.Simulation results indicate that the vibration of the space telescope can be suppressed effectively using the proposed control method,and the imaging requirements of the telescope may be realized using the least cable actuators,whose minimum quantity and position distribution are determined in this paper.