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According to the selection and evaluation of railway freight transport of the third party logistics, establish a complete set of fuzzy hierarchy evaluation (F-AHP) model of railway freight third party logistics company. Taking Nanchang Train Depot as an example of empirical analysis, Calculate and screen the most appropriate third party logistics company. At the same time, we confirm the reliability and authenticity of F-AHP method that applies to the third party logistics company, which provides reference experience for the railway freight department on the selection of third party logistics companies.

Traditional transfer alignment must use a pure Inertial Navigation System (INS) as the reference, because using the integrated navigation system as the reference would disrupt the transfer alignment process and lead to the divergence of the fine alignment filter. But there are some cases require the cooperation between the master INS and slave INS for long time duration, such as mapping. To guarantee the accuracy of the master INS, integrated navigation feedback is needed. So, transfer alignment technique using the integrated navigation system as the reference is required. Taking the error of master INS into account, a transfer alignment attitude error in the body frame was defined, which makes the transfer alignment attitude error free from the impact of integrated navigation feedback corrections. Then, its error equations were developed and a Kalman filter was designed based on it. Finally, a transfer alignment simulation using a GPS/INS integrated navigation system as reference was performed to validate the proposed scheme.

JG590 steel is one of high strength, low alloy and high toughness engineering machinery steels, and its tensile strength is not less than 590MPa. The fatigue failure is one of the main forms of the welding structure failure. This paper studies the influence of the ultrasonic treatment on welded joint fatigue performance. Through the experiments, the paper compares the fatigue performance on as-welded welding joint with the performance on ultrasonic impact treatment welding joint. The results show that the ultrasonic treatment reduces the stress concentration factor by improving the geometry of the toe of weld’ area. It transforms the welding residual tensile stress on the surface of the welded joint into compressive stress, and makes the surface of the toe of weld’ area hardening. The fatigue strength of welded joint is increased by 114%, and the fatigue life increased by 133~184 times.

A procedure for obtaining the load distribution in a four point contact wind turbine yaw bearing considering the effect of the structure’s elasticity is presented. The inhomogeneous stiffness of the supporting structures creates a variation in the results obtained with a rigid model. A finite element model substituting the rolling elements with nonlinear compression springs has been built to evaluate the effect of the supporting structure elasticity on the contact forces between the rolling elements and the raceways.

JB800 steel has grain boundary allotriomorphic ferrite and granular bainite (FGBA/BG), and it is a kind of high strength low alloy steels, which has simple produce procedure, lower cost and excelled property. The law of microstructure transformation in CGHAZ, hardness, and impact toughness in HAZ of JB800 steel were studied by means of thermal simulation. The test results show that under the general condition of welding process (t8/5=5~50s), microstructure of CGHAZ is composed of mixture microstructure of Martensite and Bainite and with the increase of cooling rate, the content of Martensite will decrease, but that of Bainite will increase; when t8/5 is 20s, CGHAZ zone have better impact toughness, which is composed of 95% Martensite and 5% Bainite. Therefore t8/5 should be controlled at about 20s to get better impact toughness.

Under the background of economic globalization and regional economic integration, B2C enterprises begin to focus on how to handle the relationship between logistics services and E-commerce services in the face of intense competition from other companies. This paper proposes a fuzzy analytical hierarchy process (FAHP) approach to select the logistics mode of B2C electronic commerce companies. In addition, a case study is presented to demonstrate how the approach can help in solving such problems in practice.

For meeting the needs of equipment maintenance support, all kinds of maintenance support data are widely used and studied. By analyzing these data, information models are put forward. XML is used to describe the models. The information models built by XML have good maintainability and portability. The unified information models will play an important role in data exchange in equipment maintenance support areas.

The electrical system fault testing and diagnosis system based on I2C-bus and embedded equipment is proposed. This system is accomplished with the integration of PXI-based computer, field fault testing platform, dedicated interface adapter unit and accessories with software program of virtual instrument and database management and fault guidance system. It can obtain various state parameters of the heavy mechanized bridge by interface adapter unit and corresponding sensors. The dedicated interface adapter unit, that is the core of the hardware platform is composed of chassis, embedded microcomputer controller, I2C-bus data acquisition modules, VPC connection package and military aviation sockets. Because of its flexibility and modular design, it can support different data conversion, for example, analog, digital, and serial, while functioning as an intelligent conversion bridge between field fault testing platform or PXI computer and electrical system of heavy mechanized bridge electrical system. The fault diagnosis software is of hierarchical modular structure with integration of system management control, fault detection and circuit hardware driver modules together with fault repair and diagnosis database. Therefore it provides functions of human-machine interaction, equipment fault detection, fault diagnosis and analysis, as well as repair and maintenance guidance The fault testing and diagnosis system in this work is also featured with handy structure, lightweight, low consumption, large storage capacity, excellent expandability and intelligent inference capability. The system can be used in the online fault testing and diagnosis of similar engineering equipments. So it has important engineering and military application value to the rapid fault testing and fault diagnosis of engineering equipments.

Local railway is mainly constructed by local investment or joint investment with other railways. It shoulders the transportation of local public passengers and short distance of railway goods, and bears the task of boosting local economy and domestic demands [1]. Choosing suitable local railway operation management mode could help to realize maximal economic benefits with least amount of investment, and best management. Through the analysis of China's local railway company operation and management model, this paper proposes five methods to guide how to choose local railway operation and management mode.

Control technology of pneumatic servo spot welding gun is studied, using the proportional flow valve as the control device. The mathematical model of the proportional valve-controlled cylinder system is established, and the experimental studies of position and force control for pneumatic servo spot welding gun have been done. The experimental results show that the servo gun opens smoothly and fast, the impact of electrode is greatly reduced, and the electrode force is controlled precisely and kept steadily, the quick changing of the electrode force is achieved in the welding process.

In view of the process of sampling switch judgment problem of alternating sampling two furnaces oxygen content with an oxygen analyzer, this paper provides an indirect method to monitor oxygen content of furnace sampling switch process based on the time and data. The experimental results show that the method can solve the end decision problem in the process of sampling switch very well. At present, the method has been applied to concrete in practical engineering, having a good effect.

There are more and more data produced in equipment management systems. For decision making, we must collect and integrate all kinds of data and information from different management systems. By analyzing the distributional and heterogeneous data resources, the architecture of equipment management data warehouse is proposed in this paper. We discussed important components of data warehouse for equipment support. The components include metadata, data market, data granularity and data partitioning. By discussing the organization of the data warehouse from the macroscopic point of view, the equipment support data management system with the function of decision making will be used in the future.

With the growth of population, shortage of water resources, natural disasters, climate change, serious shortage of land resources and the development of urbanization and industrialization and impacts of other unfavorable factors, China's grain security issue has become a focus of public concern. Through the Chinese population quantity analysis and forecast of 2020 and 2030 the total demand of grain, comparison between total demand and current level of food production, China's grain problem is facing tremendous pressure. Water conservancy is the lifeline of agriculture and irrigation has great potential for grain production guarantee. Results for food safety in China made the following responses: First, the rational use of water resources, improve the efficiency of irrigation and grain yield per unit area. Second, multiple sectors such as agriculture, meteorology, soil, make a good combination of multiple disciplines for food security. Third, increase the peasants' production enthusiasm. Last, scientific and technological progress is the guarantee of grain production. In General, the issue of food security is national security, social stability, a top priority. The combination of our country's water resources crisis, limited rational development of agricultural water resources, improve the efficiency of irrigation, which will provide a guarantee for China agricultural water crisis, alleviating the shortage of water resources and increasing food safety assurance.

A six degrees-of-freedom (DOF) parallel material testing machine (PMTM), which is based on Stewart Platform, is first proposed in this paper. Several essential issues including prototyping, compliant axis determination and controller design are investigated with specific methods or technologies. The compliant axis, along which the proposed machine has a better performance, is determined by the eigenscrew decomposition method. The proposed force controller incorporates the simplified inverse dynamic model output as a model-based portion of the controller and its validity is verified by means of simulations. Evaluation tests are performed to examine the practicability of the proposed controller and to determine the loading accuracy of the PMTM. Tensile tests and preliminary multiaxial loading tests are performed to verify the performance of the proposed PMTM. The experimental results illustrate that the proposed PMTM is capable of performing multiaxial loading tests of materials and thus a suitable candidate for multiaxial material testing machine.

The severe aerodynamic heating on the surface of modern hypersonic flight vehicle, that can bring high temperature and large temperature gradients in the structure of the vehicle, will be a challenge for the vehicles design and multidisciplinary optimization. The transient thermal environment consists of high temperature and large temperature gradients will generate two important problems related to vehicle structure, namely: 1) the material property, such as elastic modulus, will be degraded at elevated temperature, and 2) the non-uniform thermal stress cased by large temperature gradients will change the stiffness distribution of wing structure, which can make the modal frequencies and shapes of structure changed remarkably. Firstly, the theory and methodology of structure modal analysis in transient thermal environment is outlined. Subsequently, the transient temperature field of structure considering aerodynamic heating is obtained by employing computational technology of aerodynamic heating/structure heat transfer coupling program. Finally, the modal frequencies and shapes of vehicle structure under transient temperature field is calculated based on finite element method (FEM). Based on the analysis and investigation of the simulation results, the influence of the transient thermal environment on structure modal frequency and shape is determined. Furthermore, the investigation of wing structure modal analysis considering aerodynamic heating is an important basis of aerothermoelastic simulation.

With the rapid development of Chinese economy, flight delay happen frequently in many airports. Now, there is an error point in China civil aviation system that is they are all seem to hope expansion airspace to enhance capacity to solving this problem. But in fact, airline company`s service confusion leading to the airspace`s low-effective using is the major cause of delay. Only the more effective using of the existing airspace, the more benefit. This paper analyses the reasons of flight delay, explores the relation of flight delay and air traffic movements mainly, uses the analytical model to calculate the China three major airports ` punctuality rate under the condition of service level reaching the international level, which is higher than the actual data. The result shows that the service quality is the leading cause of influencing punctuality rate. Only improving the service standard, Chinese airports` flight delay can be solved effectively.

In order to improve the smoothness of electronic cam motion,an electronic cam trajectory generation algorithm based on global optimal control points of quintic non-uniform B-spline is prop-osed. This algorithm solves the problem of non-global optimization in existing approaches caused by transferring kinematic constraints into control point constraints to avoid the semi-infinite constraints problem. The interval ranges of the reserved free control point variables are calculated first, followed by partitioning and checking the subinterval with the property of the objective function and kinemat-ical constraints repeatedly until finding the global optimal control point. Compared with the existing control point constraints algorithm, the object function is optimized further and the electronic cam trajectory is smoother. Finally an practical example of electronic cam proves the effectiveness of the proposed algorithm.

Hardware connection and software implementation of communication are designed between the S7-200 PLC and Ethernet. Hardware composition is introduced and low-power microprocessor S3C2440 is selected as the control chip, DM9000 as Ethernet control chip, serial port RS-232 as testing interface. Monitoring page is designed to show the status of PLC. PPI protocol is known by analysing the communication process of S7-200 with PC. Embedded web server Boa is transplanted and CGI program is developed in Linux embedded operating system. It can realize the function of reading and writing I/O value and simulation value. The experiment shows that the system can realize reliable serial communication. It brings a great convenience to work.

In this paper, the typical aircraft panel is excited by the noise induced in traveling wave tube, the vibratory phenomenon of the typical aircraft panel is researched in detail. The piezoelectric vibration of the aircraft panels is damped by Synchronized Switch Damping on Inductor technology (SSDI technology). The acceleration parameters of the structure are controlled and the effect of structural damping is achieved.

In this paper, with a 92,500 ton bulk-carrier being mainly taken as an example, the preparing design of launching processing scheme on the horizontal berth is discussed. Calculation of needed hulling force and strength examination of hoisting pad are done, and then the structural strength of hoisting pads and their stiffening structures are analyzed with the aid of finite element technique. Once the total assembly of hull is completed on the berth, the launching weight should be calculated and proper number of box-beams should be determined. Sliding frictional media used between box-beams and slipping-rails should be selected, and according to combined frictional coefficient, the needed pulling force by which the hull may be hoisted forward securely should be fixed. In order to assure the safety of ship in the period of launching, strength examination calculating for hoisting pads and stiffening members should be done by means of finite element method as soon as their types and assembling positions are determined, so that the strength of hoisting pads and stiffening structures should be able to meet the requirements. Owing to that this ship having being successfully launched, the reliability and usability stated in this paper have being verified. Therefore, it is of quite value to be referred in technical analysis for launching on the horizontal slipway.

When comparing with ship construction within newly-built docks or on tilting slipways, ship constructing on the flat earth method can be said to be a new ship-building technique by which ship is built on a platform and launched with the aid of floating-dock or barge. Some obvious advantages of this technique are such as less investment in basic facilities, low production cost, high production efficiency, wide applicability of ship types, ability to overcome the bottle-neck effect of berths and docks. In this paper, a bulk-carrier being taken as an example, the design of launching processing scheme on the horizontal shipway includes calculation of launching weight and determination of hoisting force during the whole towing period. The whole towing process of hull can be divided into three stages, the first is from the static state to the moment of beginning to move, the second is from the initial position of movement to the front of slipway onto which the hull is predicted to be pulled, and the third is from the front of slipway to the designated position on the floating dock. Subsequently, after the hull being sealed and positioned correctly, the floating dock for launching may be towed to deeper water zone and the hull can be buoyed up on the water surface, and the whole launching process can be completed. From the research, the conclusion is made that the launching technique of this paper is available and feasible. Especially, this paper is the initial application of this method on the 15000t launching ship home and has the epoch-making sense.

This paper presented the loss of the power grid and elaborated the distribution features of the power grid in Anhui, pointed out that measures should be taken to improve the structure of Anhui power grid for energy-saving according to its own specific characteristics. Suggestions includes the construction of UHV power grid, the breaking out of looped network, the construction of multi-circuit transmission lines on the same tower, scientific adjusting the grid operation voltage, improving the power factors, and adjusting the load. Based on the rules and characteristics of grid power loss, measures should be adopted on special ways to get the largest energy-efficient operations and achieve the aim of less investment to increase economic efficiency.

A method for the vibration and noise reduction of a typical aircraft panel structure under noise excitations is studied. The noise excitations are caused by travelling wave test device, and the experimental is performed by the piezoelectric switching shunt circuit based on the piezoelectric effect.

Equiped with an electronic differential function in double wheel or four wheel electric vehicle drive, it must be driven by motor torque control precisely . Due to the nonlinear characteristics of the motor when the wheels switched reluctance motor drive, it is difficult to ensure motor torque and phase current relationship by the theoretical approach. This paper puts forward the experimental methods to get the different speed motor torque and given the relationship between the current , so as to make table, according to the rotation of the motor speed and torque requirements, the accurate switched reluctance motor torque control through given the current value in the future of the electric vehicle.

For uneven temperature distribution of infrared hot recycling of asphalt mixtures, principle and advantage of microwave hot recycling are introduced. Maxwell's equations are applied to build electromagnetic transmission model of recycled asphalt mixtures. Considering asphalt mixtures as dielectric substance, reflection and refraction of electromagnetic field are researched and model of standing wave ratio is built. Equation of magnetic attenuation is applied to contrast attenuation depths of different pavement materials. The results lay a good theoretical foundation to improve heating efficiency and choose pavement materials.

Based on the analysis of the characteristics of the RT-Thread and Cortex-M3, show the superiority of the combination of the two. On the study of RT-Thread and Cortex-M3 system structure and characteristics, RT-Thread is ported to the Cortex-M3 Skillfully. The PendSV exception of Cortex-M3 which can automatic saves part of the registers is used in the process of context switching to reduce the time of thread context switching, and improve the real-time property. This can be as a state-of-the-art design architecture used in intelligent instrument. The system is stable in the practical test, and possessed of popularization and application value.

Although the bag-type dust collector is dust capture equipment which is low cost and high efficiency, it has less filter efficiency to ultra fine particles for its of thicker fiber. So ultrafine fiber were used by bicomponent fiber with splitting craft to improve the filtration efficiency of ultra fine particles greatly. A piece of polyester/nylon sea-island superfine fiber needled nonwovens were splitted processing for nine times by the orthogonal design. And fibre microscopic photographs, weight loss rate and strength were analyzed. The best choice of splitting craft as followed: lye concentration is 16%, splitting time 15 min and splitting temperature is 95 °C.

This paper explains and demonstrates the operation mode and management characteristics of self- supporting railway company. According to these characteristics, the paper designs and analyses process framework of primary business for local railway company. And it designs the process of transportation planning, transportation scheduling operation, train operation organization and freight organization respectively based on the idea of self- supporting management mode. Finally, this paper analyses the advantages of transport organization process design for self- supporting railway company.

According to the unified theory of general concrete filled steel tube, this paper puts forward a constitutive relationship model of the self-stressed concrete filled steel tube, which was verified by experiments and finite element methods. On the basis of the above, the influences on the bearing capacity of self-stressed CFST members were analyzed about the strength grades and magnitudes of self-stress of confined concrete. The results show that the bearing capacity of the self-stressed concrete filled steel tube members will be improved with the increase of the magnitudes of self-stress and concrete strength grades. Compared to the general CFST in the same condition, the maximum of the bearing capacity can be approximately enhanced 20%.

Although biosorption for reclaiming single precious metal was frequently reported, the actual subsistent adsorptive competition among different metal ions sometimes shows diverging reinforcement or prohibition for different species. This study tries to screen bacteria that are able to absorb certain precious metals with high selectivity under competitive conditions. The activated sludge was cultivated from enrichment by magnetotactic bacteria medium proposed by Blakemore. Then four microbes, microaerobic bacteria(A) acclimated micro-aerobic bacteria (B), anaerobic bacteria(C) and acclimated anaerobic bacteria(D) were obtained for the following adsorption experiments. The four microbes have high removal efficiency of Au3+ both in its unitary and Au3+-Cu2+binary system. The microaerobic bacteria (B) are good metal catchers and carriers for the uptake of gold in aquatic solution with coexistence of copper. In Pd2+-Cu2+system, there is a collaborative adsorption effect, especially on (B).

The Whole-cell patch clamp technique was used to study the properties of voltage dependent ion channel expressed by the cultured types A、B、C neurosecretory cells dissociated from medulla terminalis X-organ (MTXO) of Chinese mitten crabEriocheir sinensis24-48 hours after plating. Under voltage clamp conditions, significantly inward currents were recorded from all three kinds of neurons, followed by large outward currents. When outward currents were suppressed with use of 3mmol/L 4-aminopyridine (4-AP) and 30mmol/L tetraethylammonium (TEA), a tetrodotoxin-sensitive Na+current （INa） and a slow (time to peak current 6~8mS at +10mV), Cd2+-sensitive Ca2+current (ICa) were resolved. INawas activated at potential-40mV and was maximal at-10mV. In TTX, ICawas activated at potential-30mV, was maximal at 10~20mV. In the presence of 1mol/L TTX and 0.5mmol/L Cd2+, a 4-AP-sensitive transient current and a slower-rising, TEA-sensitive current were recorded from a holding potential of-50mV. On the basis of electric feature and pharmacology, transient current was identified as IA, and late, slower-rising current as IK. IAand IKshowed the same activation threshold of-30mV. In conclusion, no differences were observed on the properties and kinetics of ionic current among the three kinds of neurons. By comparison with those described in crabCardisoma carnifexand crayfishProcambarus clarkia, there existed diversity of excitability in X-organ peptidergic neurons from different crustaceans.

Based on modern ideas of thermomechanics, small strain dynamic dissipation function of Hardin-Drnevich model for soils is formulated using the assumptions of the beeline and the skeleton curve shift laws. The first and the second threshold shear strain are proposed. Both the two threshold shear strains do depend significantly on the dynamic parameters for soils. Comparison between the results of eight kinds of cohesionless soils, it is shown that the two threshold shear strains decrease when the maximum dynamic shear modulus coefficient and exponent increase. The first threshold shear strain basically does not change with the change of internal friction angle. However, for the second threshold strain, a monotonically increasing function and monotonically decreasing function can be used to model the change with respect to the internal friction angle for the beeline and the skeleton shift stress respectively.

The damage caused by blasting vibration on rock mass is an extremely complex process, and has certain impact on the mechanical properties and bearing capacity of the rock, which will affect the overall stability and safe operation of the construction. Therefore, studying on the damage effect of blasting vibration is very necessary. Taking Laxiwa hydropower station project as a background, the paper computed relative velocity response spectrum using monitoring and measuring blasting velocity as an excitation, then analysis was carried out to study the relationship between the depth of rock blasting and the integral value of relative velocity response spectrum as well as the index of cooperation of the integral value and the blast vibration’s duration time. The results show that using three-parameter (velocity, frequency, duration time) was clearly superior to two-parameter (velocity, frequency) on studying the damage fracture of rock blasting, and two-parameter was better than one-parameter (velocity) by analogy.

In this paper an optimal maintenance policy for a Reactor Protection System (RPS) for a nuclear plant was developed. RPS consists of continuously operating sub-systems that were subject to random failures. A block system diagram for RPS had been proposed that facilitates analyzing of individual sub-systems separately. The proposed maintenance policy is the Age Replacement model, which incorporated both corrective and preventive maintenances. A Markov model was used to optimize the preventive maintenance interval of those sub-systems whose failure and repair rates were exponentially distributed. Finally, a sensitivity analysis had been performed and recommendations for maintaining the required RPS availability have been suggested.

This paper briefly introduces silicone and the material’s properties and performance, and explains the silicone polymer with high-performance used in building innovative preservation, furthermore, the protection mechanism of silicones was presented. It shows that silicones can improve thousands of building materials work better and make architecture have longer life.

Single Column shaped bridge is often used as a city program, it has the separate grade crossing, and multi-entry multi-exit, and greater clearance under the bridge, etc. But its stress situation is more complex, for designers and construction workers, put forward higher requirements. This article embarks from the stress of single Column shaped bridge, comparative analysis shaped bridge and curved bridge, concreting continuous beam bridge differences and similarities, and proposes the support way to the heterogeneous bridge's influence. Based on the single column bridge study, we find a simplified method on modeling, and its accuracy is in line with requirements of project. Finally, analyzes of the actual bridge, verifies the correctness of the calculation method, and proposes the key technologies.

This paper describes the complexity and particularity of the trajectory of tube-sphere intersection and derives mathematical model of the track; according to characteristics of B-Spline curve, the track intersecting curve is partitioned ,and determine the mathematical relationship between the control points (deBoor point) and the data points of J-type groove; using cubic non-uniform irrational B-Spline theory, generate segments of approximation curves, then first and last point of each segment are constrained, so that combination curves can be seen as a whole curve with C1continuity; programming the trajectory of the preprocess module with C# language, it has advantages of approximate accuracy and high efficiency, thereby it can increase accuracy and precision of welding terminal position, so that the overall system has a metronomic characteristic.

Unascertained clustering is an unsupervised clustering based on unascertained set. It is a method to make soft division of objects which is more scientific and realistic than the general one. According to the basic idea of unascertained average clustering, we write a specific procedure to achieve calculation by the MATLAB technology and then we verify the feasibility and effectiveness of the written procedures as well as the practical value and feasibility of calculation through case study.

Input-Queued switching fabrics are widely used in high speed network switches for their scalability. However, a scheduling algorithm must be elaborative designed for input-queued switches to get high throughput. The randomized algorithms are attractive in kinds of scheduling algorithms for their low complexity and well performance. In this paper, a fluid model is introduced to analyze the rate stability of switching systems with randomized schedulers. By this method, we proved that the randomized scheduling algorithm can achieve 100% throughput under any admissible traffics which satisfy the strong law of large numbers (SLLN).

Residual stress on the machined surface and the subsurface is one of the most important factors that can influence the service quality of a component, such as fatigue life, tribological properties, and distortion. In this work, a 2D FEM model of AISI 52100 hard turning processes is setup. The material properties are widely selected to describe the material property more precisely. By using user subroutine named Konti-Cut, the steady state of cutting process is simulated and the cutting forces and residual stresses in this time are investigated. By comparing the cutting forces, the FEM model can gives quite good appliance with experimental data. And the basic relations between residual stresses and cutting parameter, tool geometry are drawn.