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In order to provide the theory and experiments for the polarized skylight navigation, the polarization patterns of moonlight were discussed in this paper. The polarization patterns of moonlight were simulated by Matlab based on Rayleigh scattering theory. The polarization patterns of full moonlight were obtained by the full-sky imaging system in clear sky. The neutral point and the meridian contain the distribution characteristics of polarization patterns. Compared the tested results with the theoretical polarization patterns of moonlight, the neutral pointand the meridians of the measured polarization patterns of moonlight were studied. The results showed that the tested polarization patterns of moonlight were in agreement with the theoretical polarization patterns basically.

Cylindrical grating angle sensor is a common angle measuring device with high precision. Due to the reflecting arc surface of the cylindrical grating the effects of relative displacement of graduation line and gap variation will interact. Significant residual errors still exist even with high precision cylindrical grating and multiple reading heads around the scale disc .In this paper, based on the principle of circumference closure, the principle of self-calibration is deduced and analyzed in detail. The calibration curve is obtained by obtaining the deviation between the certain position and an ideal position of the graduation line position in real time. A simple self-calibration method of cylindrical grating is acquired. It can calibrate random errors and system errors with time and improve the angle measurement accuracy. The method has the advantages of simple structure and strong maneuverability, and provides technical means for the miniaturization and high precision of cylindrical grating.

Arch bridges will produce horizontal internal force at arch springing under vertical load. The horizontal internal forces and displacement of abutments have significant influences on structural behavior of arch bridge, which was located at soft soil foundation. One of the effective methods to solve the problem is applied the pre-pushing technique behind abutment by two horizontal anti-slide slab. However, there is soil creep deformation at the arch springing under the long-term vertical load. Therefore, an unequal interval multivariable grey model was established to predict the soil creep deformation. This grey model was extended by a single point and equal interval model. The modeling steps are also proposed in this paper. And then the calculated results by the proposed model will compared with the measured results and the results of Burgers model. The compared results showed that it can precisely and effectively predict the amplitude of the creep deformations.

Storage tank is an essential vessel in petrochemical industry, and the corrosion of tank is an important reason for the safety hazard. The corrosion of tank bottom plate is more serious than the tank wall, and it is not easy to check and repair, when damaged to a certain extent it will cause the leakage of the media, then lead to waste of energy, environmental pollution, at the same time it will cause a major accident. Magnetic flux leakage testing is widely used in the field of tank floor inspection with the advantages of fast scanning speed, accurate results and so on. In this paper, the finite element simulation and analysis of the corrosion defect leakage magnetic field is used to obtain the data, and the characteristic of the leakage magnetic field is extracted. The effect of defect depth and width and shape on the magnetic flux leakage field is studied, and the distribution curve of the magnetic flux leakage field is obtained.

In this paper, finite element method was used to carry out parameter optimization and structural improvements of CNC machine. Considering the static and dynamic characteristics of the machine, the headstock and bed of CNC machine has been improved by structural optimizationk, and wall ribs was designed on the headstock CNC machine tools. After optimized the static stiffness and strength of CNC machine can meet the requirements, with a decrease of approximately 24.8% in weight compared to the original machine design.

Space solar power satellite (SSPS) as a very large flexible spacecraft structure with complex configuration, large size and number of units bring the difficulties to dynamics modeling and analysis. Considering SSPS structure characteristics, equivalent strain and kinetic energy theory is adopted to establish the equivalent beam model of SSPS truss structure. The assumed mode method is adopted to describe the flexible body. The modal truncation method implements the dynamics system order reduction. Mixed coordinates method is adopted to establish the rigid-flexible coupled dynamic model. The established dynamic model can reflect dynamic characteristics of SSPS, achieve control requirements for SSPS and decrease the workload of simulation calculation. The independent modal space control (IMSC) method is proposed to active control research view of the large displacement, nonlinearity, low and dense mode frequency, light damping of flexible structures. Simulation results on flexible solar array show the effectiveness of the control method.

In the paper the total FE model of the MAN gas holder is built to analysis oil leak problem of MAN gas holder in steel plant. By comparing the FE result and theoretical result of MAN gas holder under internal pressure, it is observed that they have high consistency, which proved the reliability of FE model, and provided valuable basis for the following calculation. The main body load of MAN gas holder is circumferential stress, which is observed in total structure analysis result of the MAN gas holder. This kind of stress distribution proved to be the main reason of oil leak.

Modern timber buildings are more and more popular with their characteristics of green, environmental protection, low carbon. According to their structure, they are divided into light wood frame construction, sawn and log timber structures, glued laminated timber structures, log cabins. This paper analyzes the structure supporting structural system of log cabins, from material requirements, structural design to production process, supplemented by practical case to demonstration, to explore the design method of log cabin’s structure supporting system.

The stability of slope in open-pit affects the economic benefits and safety production of mining enterprises. From the two aspects of internal factors and external factors, this paper analyses the factors affecting the slope stability of open-pit, discusses the basic theory of slope stability analysis, and puts forward the criterion of slope stability based on the safety coefficient. The limit equilibrium method is chosen to analyze the stability of the high and steep slope of open-pit in this paper, and the SLIDE software is used for numerical simulation according to the actual slope model of certain open-pit. The simulation results show that the slope safety coefficient of the instance is 1.01, which is unstable slope. When the number of the slope blocks is more than 40, the safety coefficient tend to be stable. Blasting vibration has a great influence on slope stability. The results of slope stability analysis provide a scientific guidance for the prevention and control of the slope instability.

While axial piston pump is the core component of hydraulic system, its service life and reliability depend much on the selection of materials, friction pairs and process parameters. To identify these factors, wear condition of friction pair is conducted by using MWF-10 wear rig. Based on ANOVA of Taguchi Method,the influences of surface roughness and hardness on wear loss and friction coefficient are compared. In addition, the results show that the optimal friction pair and surface roughness of hard specimens have influence mostly on the wear loss and the friction coefficient.

Mobile robots have been widely used for the good adaptability, payload capability. Robot cooperation brings benefits for the task in a multi-robot team. In this paper, the modular hardware design of a leader-follower mobile robot team is discussed, including the distributed control architecture and the electronic system of each robot of the team. The basic idea behind this paper is to introduce the design of the hardware and distributed control architecture, which mainly manages the distributed control system, consisting of microcontroller modules connected through a data bus. The research has a potential applying prospect in mobile robot tracing and locating in the future.

Based on the dynamic analysis of ANSYS for the intense state of cutlery and ice, the device can be judged whether it can successfully finish the ice and snow removing job. And the process of straight cutting tool of the same height, width and length with the bending one removing the same ice is analyzed using ANSYS under the same the situation. So the stress distribution diagrams were studied. Comparing the stress distribution diagrams between the cutting tools and ice and snow, some results can be gotten. In addition, the rationality of the choice of cutting tool can be proved.

By using analytical and finite element analysis method, this paper analyzes the various factors on the impact of EDM surface roughness, puts forward a new mirror machining method of changing the order of the processing conditions and increasing the momentum of the swinging electrode in the process of EDM. Puts a measuring method for the surface quality with white light interferometer characterized by non-contact, high precision and vertical resolution in nanometer. Experiments show that in the non-mixed powder fluid, without replacing the electrodes and the processed work-piece is 45 # steel, the surface roughness of work-piece is 0.02 micro-meter, which meets the requirements for precision of the electrical discharge mirror machining.

Considering the refuse and leachate as one whole system, a conventional landfill (CL) was set as a control, transformation of dioctyl phthalate (DOP) in recirculated landfill (RL) and bioreactor landfill (BL) was studied. Results showed that DOP was detected in both leachate and refuse from CL, RL and BL. The initial DOP amount was 0.8 μg g-1 in the landfill refuse. At the day of 310, refuse sedimentation rates were 7.0%, 11.9% and 24.3% in CL, RL and BL, respectively. DOP removal rates were 17.4%, 30.8% and 31.7% in the refuse from CL, RL and BL, respectively. The residual amounts of DOP with significant differences well fitted exponential decay models in CL, RL and BL. DOP biodegradation was accelerated with the operation of leachate recirculation compared to the conventional operation, and it was further promoted with the introduction of methanogenic reactor.

A 250-kW organic Rankine cycle system comprised of a preheater, evaporator, condenser, turbine, generator, and pump was used to study its off-design performance and operational control strategy by the flow rate control approach of the working fluid R245fa. The net power output was 243 kW, and the system thermal efficiency was 9.5% under design conditions. The analytical results demonstrated that the flow rate of the working fluid increased with increasing the heat source temperature (TW,in); higher TW,in yielded better heat transfer performance of the designed preheater as well as a higher requirement for the evaporator’s heat capacity; and the net power output increased linearly with increasing TW,in.

Arthrospira (Spirulina) platensis contains large quantities of γ-linolenic acid (GLA). GLA is an essential omega-6 unsaturated fatty acid made in the human body from linoleic acid. It can be metabolized to various important eicosanoids such as prostaglandins, thromboxanes, leukotrienes, prostacyclins, and lipoxins. The aim of this study was to investigate the optimal extraction parameters of GLA from A. platensis using supercritical CO2 technology. Results showed that operating temperatures and pressures were important factors in the extraction of GLA. A maximum GLA yield of 161.98 μg/g could be obtained at a pressure of 30 MPa, a temperature of 60°C, and a CO2 flow rate of 6 mL/min. Conversely, only a yield of 104.16 μg/g could be obtained at a pressure of 10 MPa, a temperature of 40°C, and a CO2 flow rate of 6 mL/min. The correlation between pressure and yield could be explained by an increase in collision rates between CO2 molecules and carrier affinity under a high pressure. Therefore, an operating temperature between 50 and 60°C and a pressure of 30 MPa should be used to maximize the yield of GLA from A. platensis using supercritical CO2 technology.

In the paper double-cone seal of ammonia converter is analyzed by means of the finite element method. The contact nonlinear FEM is adopted to simulate the process of double-cone seal in the pretension condition and the operation condition. The curve of contact stress versus time is generated based on the simulation. The stress distribution of plat head and seal ring identified that the standard radial clearance design in GB150-2011 is reasonable and can meet the seal requirements. The deformation and stress distribution evaluation of the entire double-cone seal is further conducted. Bolts load obtained from analysis result and theoretical value of the two conditions are in good agreement, and the deviation is less than 2.1%, which proves that the simulation result is reliable.

In this paper, the three-dimensional motion of two bubbles in melt Aluminum was simulated by using level set method. Through changing the positions and sizes of two bubbles, the influence of bubbles wake flow and their interaction are considered. Our numerical simulations demonstrate the bubbles characteristic behavior such as distortion, attraction, and repulsion. The velocity field around the bubbles reveals the interaction between the wakes of two bubbles in fluid dynamics. For the two bubbles placed horizontally or vertically, it is found that the coalescence of bubbles may happen when 50% of the below bubble’s projected area enters the wake zone of the upper bubble.

With the living standards improvement of rural residents, people pay more attention to the safety of drinking water in China. As the final step in drinking water treatment, disinfection technology has received much attention. At present, drinking water disinfection process is mainly involved in chlorine disinfection, chlorine dioxide disinfection, chloramine disinfection, disinfection of potassium permanganate, ozone disinfection and ultraviolet disinfection. However, due to limitations in rural economic conditions and management level, only ozone disinfection and ultraviolet disinfection are suitable for rural areas in China. This paper described some of the application problems and limitations in drinking water disinfection process, as well as the select principle in rural areas. The principle, research status, trends and issues in application of ozone and ultraviolet disinfection technology were emphatically introduced. Finally, the development of drinking water disinfection technologies was discussed.

Four single-story single-span Gabled Frame Structures (GFSs) which included in China national Standard Design Drawing of Light-weight Steel Structure with Gabled Frame (02SG518-1) were studied and their longitudinal seismic performances were evaluated through extensive nonlinear time-history analysis using eight ground motions representing the Frequent Earthquake, DBE and the MCE hazard levels, the load-bearing performances, deformation capacities and the curves of displacement were studied. The analysis results showed that the longitudinal seismic action of all GFSs considered in this study is very little, the displacement at the top of the column can satisfy the demands of the Technical Specificationfor Steel Structure of Light-weight Building with Gabled Frames even in MCE. The GFSs designed followed the Specificaiton have the excellent longitudinal seismic performance.

In order to study the application of Weibull distribution in cable partial discharge pattern recognition. We apply a 10kV 30m XLPE cable for this study. Then design four kinds of typical artificial defect model and analyze each of defect model’s discharge pulse signals. Finally, estimate the Weibull distribution of signals by use of the maximum likelihood method. The results show that Weibull probability distribution is similar to partial discharge amplitude distribution, the shape parameter β can be used to identify different types of discharge.

The theory of gait is one of walking ways which is efficient, fast and stable in a variety of industrial robots, offering a structure of climbing robots in a way of gait and climbing with the gait motion in paper. Through the results of analysis by various industrial software, the presented structure of climbing robots which is composed of two terminal parts and two robot arms that is the part of pedestal and climbing mechanism. In the process of climbing, realizing gripping, Swing work, turning work, an orderly motion and get to the aimed place finally through alternate between the upper and lower part of the body by the control of SCM. The presented method has not only improved many problems like complicated climbing structure, controlling rough, slow-motion and unable thronging obstacles, but also accomplished the subsequent operations like tools delivering, pole testing, clearing, maintenance work, furthermore, there has more comprehensive benefits.

Due to the current existing outdoor trash put, cannot effectively separate collection, easy to produce odor and other issues, In this paper we designed a solar intelligent trash. The trash can has a better appearance, can effectively separate collection, automatic flip, the use of solar power to achieve lighting, voice prompts, deodorant and other functions. Smart trash concise design, environmental protection, and harmony.

In recent years, our some rare earths have been mined improperly, causing some problems like environmental damages and the desertification of land in the mines. There is a necessary to restore them ecologically. In this paper, fuzzy comprehensive evaluation analysis was used to select all evaluating indicators implementing the land reclamation in a mine, and then expert judging method was to evaluate them with their comprehensive subordination degrees and their scores. Not only did these scores showed a good performance, but these solutions gave an example to other mines with a fact that this process was proofed feasible and scientific to evaluate the effectiveness of land reclamation.

Based on the characteristics of space truss structures, the concept of modal strain energy is introduced and square difference in elemental modal strain is presented. Through the square difference in elemental modal strain and wavelet transform, this paper presents a method for space truss structure damage recognition. The structural damage index is presented with the change of wavelet coefficients. Numerical simulation results show that: this method is effective to locate the single, multiple damages and light, severe damage with the first mode information. The preliminary tries for damage extent identification were made by the wavelet coefficients.

The purpose of this experiment was to study the inoculation and start-up, domestication and cultivation of ANAMMOX system and the stable operation after the successful start-up. The experiment used the activated sludge SBR reactor and artificial raw water. The inoculated sludge included nitrification sludge, anaerobic sludge and garden soil exudate. The ANAMMOX s ystem was s uccessfully started on the 114th day after the inoculation. The removal ratio of NH4+-N, NO2-, and NO3- -N mostly was 1:2.8～3.6:0.2～1.8. It could be inferred that in addition to Anammox phenomenon, there was other denitrification process without the participation of external carbon sources in the system In the stable operation period, the sludge was flocculent, and the flocs were dispersed, irregular shaped. The sludge was mixed with a large number of red, dark red particles.

High-Temperature Superconducting (HTS) cable has the merits of high capacity, low line loss, narrow corridor, and environmental friendly, which has bright prospects for current tendency of accelerating development of renewable energy, shortage of available land, and awakening of environmental awareness. In the past decades, HTS cable technology made remarkable progress. Based on the past and current situation, the paper introduces the HTS materials for cable and presents the structures, classification, heat losses, and cryogenic method of HTS cable. Overview of HTS cable research in typical country is stated and representative HTS cable projects are listed. In the end, application outlook and development tendency of HTS cable in the future are made.

In order to improve the power quality problems caused by electric vehicle charging equipment, this paper put forward the research on Application of Unified Power Quality Controller (UPQC) in the charging field. Based on the mathematical model of UPQC, current control unit with state feedback single loop PI controller and voltage control unit based on dual PI loop controller are designed. Based on the mathematical model, the design reference parameters are derived. Finally, a UPQC prototype is developed and experiment is carried out, results show that UPQC has good application prospect in the field of electric vehicle charging.

IEC61850 uses the abstract communication service interface (ACSI) and specific communication service mapping (SCSM) definition method. Most of data structure and communication service are mapping to Manufacturing Message Specification (MMS), but MMS has high abstraction, many 61850 ACSI services are mapping to one mms service [6]. At the same time there are many fuzzy definitions even mapping deviation phenomena, different vendors may have inconsistent understanding to the standard, this is harmful to the interoperability. This paper provide analysis and comparison to the 61850 ACSI services mapping to the MMS read, including GetDataValues, GetDataSetValues, GetBRCBValues and so on, and based on these, firstly gives implementation using the mms-ease lite of SISCO Company and detailed explanations of actual telegram. Our research is helpful to eliminate understanding difference and achieve interoperability. System test uses multiple popular software of different company to simulate as server, and the widely used network protocol analyzer software Omicron IEDScout is used to capture packets, the result verifies our implementation satisfy the functionality and interoperability.

The shortcomings of current on-line condition monitoring system include: the research was concentrated in AC substation; the function was single and completely independent; the protocols were not compatible and the interface was not unified. To improve these disadvantages and better satisfy the needs of the condition monitoring in converter station, the design and implementation of condition monitoring and decision support system in HVDC converter station was realized. By studying of condition monitoring method, decision support technology and engineering application of HVDC project, the system design principle was discussed, the software structure was shown and the function realization was given in detail. The implementation realized real time monitoring for running equipments, provided reliable gist for maintenance and reduced the costs of resources. The implementation is applied to HVDC project witch has a great significance in improving the operation efficiency and promoting the smart grid construction.

this paper develops a kind of nano infrared smoke material with static explosion contrast test with copper powder material. In the condition of reducing charge amount, the smoke property has been improved to a large extent. The loading density of original copper powder material is 2.3 g/cm3 with effective shielding period of no more than 60s for intermediate & far infrared and action area of 100 m2. However, nano infrared smoke material, with density of no more than 1.6 g/cm3, can have an effective shielding period of more than 70s for intermediate & far infrared and action area of over 120 m2.

In order to measure capture performance of the seeker in the typical terminal guidance scene under HPM damage effect, the paper proposes a new method to model the dynamic capture state in different ballistic position. The proposed missile-target geometry count can be used to process multiple data generated in multiple Monte Carlo simulations under the same scene, which facilitates capture performance comparative analysis between different scenes. Simulations validate proposed counting measure, so that it can be applied for measuring the performance of missile capture.

Benzyl alcohol was selectively oxidized to benzaldehyde with iron (III) complexed to tetra amido macrocyclic ligands (FeIII–TAML) as catalyst and 30% H2O2 as oxidant. The effect of reaction temperature, reaction time, solvent, amount of catalyst and oxidant on the reaction of catalyzed oxidation of benzyl alcohol were explored. The conversion and selectivity of this oxidation reaction were calculated from calibrated GC yields of benzyl alcohol and benzaldehyde. When oxidation reaction was conducted under the conditions: solvent NMMO: ethanol = 1: 1, n (H2O2): n (benzyl alcohol) = 2, n (catalyst): n (benzyl alcohol) = 1%, temperature 80 ̊C and reaction time 60 minutes, the conversion was 91.23% and the selectivity was 90.12%.

In the last several decades, a couple of fuzzy power flow algorithms were presented to deal with the uncertainties in power grid. But there is no a functional simulation tool introduced to simplify the calculation. This paper presents a simulation tool, Matpower, under one of the algorithms to do the fuzzy power flow calculation. The algorithm gives the user the possibility to specify fuzzy numbers to represent the possible behavior of loads and generations and outputs fuzzy membership functions for voltage magnitudes and phases, active and reactive power flows and generations. Matpower, as a simulation tool, was modified to handle fuzzy numbers and show fuzzy results. In a final section, we present results obtained with a case study based on a real power system to illustrate and highlight details of the proposed algorithm. Suggestions for future implementation of the fuzzy Matpower are also summarized.

The optimization of the camera’s intrinsic and extrinsic parameters is a key step after obtaining the initialized parameters’ state by considering the homography between the board space plane and the image plane in Zhengyou Zhang method. In this paper, we proposed a camera calibration optimization algorithm by adopting genetic algorithm and the simulated annealing algorithm. The experiment results demonstrate that our algorithm can improve the precision of the camera calibration to a certain extent.

Large energy consumption, serious pollution and poor quality of indoor thermal environment are generally seen during construction in villages and towns in China nowadays, leading to poor building insulation performance. Envolope of enclosure of a buidling is key to its insulation performance. Material selection of building enclosures and green design of construction technology are the key to promoting insulation performance of the building as villages and towns in cold region are subject to special geographical position, climate conditions and economic factors. With a focus on research of traditional non-wood fibrous material modification with existing technology and the engineering practice in non-wood fibre roof in villages and towns of cold region, this paper came up with the prospects of its applicatin in the following design strategies including “ecological and conservation-oriented roofing with modified local materials, new hybrid roofing with simplified construction technology and paper tensioning roofing with innovative synthetic materials”.

Doping different concentration of ZrO2in Mn:Fe:LiNbO3crystals, a series of Zr:Mn:Fe:LiNbO3crystals were grown by the Czochralski method. The infrared transmission spectra and the photo-damage resistant ability of the crystals were measured. The OH-absorption peak of Zr (2mol%):Mn:Fe:LiNbO3crystal shifts to ultraviolet. The photo-damage resistant ability of Zr (3mol%):Mn:Fe:LiNbO3crystal is about three orders of magnitude higher than that of Mn:Fe:LiNbO3crystals. The diffraction efficiency, response time of Zr:Mn:Fe:LiNbO3crystals were measured by two-wave coupling experiment. The response time of Zr (3mol%):Mn:Fe:LiNbO3crystal is only one tenth of that of Mn:Fe:LiNbO3. The mechanism of OH-absorption peak shifting and improvement of holographic storage properties was discussed.