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Thepresent work investigated the effects of grain refiners Mg-30%La alloy on theimpact properties of Al-7Si Alloy. Theresults showed that the addition of Mg-30%La greatly fined the crystal grain. As La content increased in Al-7Si alloy,the alpha-Al with dendritic crystal were refined and the trend of the equiaxedcrystal had obvious enhancement. The introduce of the Mg-30%La cangovern the morphology of the Si phase. With increase of Mg-30%La content,refining effect was better.

The working profile of the roller gear indexing cam is sophisticated space curved surface. It is difficult to get the 3D model with conventional cartography. In this paper, a parameter molding method of the roller gear indexing cam based on VB and UG is provided. A system is compiled.The Simulation and Kinematics Analysis of the roller gear indexing cam mechanism can be done after the parameters are completely set. It hopes that the flaw and other problem in design can be found though this simulation and kinematics analysis, which is facilitate the designer to improve the design in time.

For the complexity of its space surface,the rapid measuring technology of machining errors for roller gear cam has always been a difficulty.In this paper, the NC machining technology of roller gear cam is introduced first, then a rapid measuring method for roller gear cam center distance error is put forward,and a error analysis model is established, last the machining experiment is done to verify the feasibility of the method.

In this paper, a king of Bearing mounting machine for gear box bearing was developed because of much problem in the manual assembly. The control system of the push mounting machine based on the Mitsubishi PLC was expatiated. The real time displacement and the pressure can be displayed with the help of Delta touch panel, and also the real time curvilinear of the key parameter.

Molecular imprinting technology (MIT) is a developing technique with high recognition which is just like the recognition between enzymes and antibodies in the organism. Molecularly imprinted polymers (MIPs), synthetic materials obtained using the imprinting technology, have played a huge advantage and been used in many fields. Especially, MIPs have been applied to the extraction and separation of analytes as the selective adsorbent of solid-phase extraction (SPE), which is known as molecularly imprinted polymer solid-phase extraction (MISPE) in recent years. In the present review, the methodology of MIPs preparation and evaluation are explained. Moreover, recent great developments of SPE and MISPE are discussed, and the potential application of MISPE in extraction of traditional Chinese medicine (TCM) active ingredients are also presented briefly.

An online coal measurement system, which is based on the prompt gamma neutron activation analysis (PGNAA) technology and uses a D-T neutron generator, is studied in this work. To improve the analytical precision of the element in coal, the original moderator is optimized. The standards of the optimization are (1) the neutron flux increase 50% after moderation; (2) the proportion of thermal and middle-energy neutron and fast neutron is nearly equal to 1:1. Using Monte Carlo method, the moderator has been optimized by adding the uranium238 to the original moderator, which consists of high density polyethylene (HDPE). The simulation results show that the optimization standards can be basically satisfied when the thickness of the uranium238 and HDPE are 4cm and 1cm respectively. On this basis, preliminary study on introducing the channel to moderator is carried out. The preliminary results show that the channel can improve the total neutron flux. But also, it will decrease the proportion of thermal and middle-energy neutron and fast neutron.

In order to grasp the state of full life cycle of the power transformer, A new method for power transformer life analysis based on risk assessment is proposed in this paper. Firstly power transformer risk assessment is conducted and fault tree is established accordingly to make the complex transformer faults system subdivide into various kinds of basic types directly; Secondly, the Fuzzy Analytical Hierarchy Process (FAHP) is designed to analyze the fault tree, so the complex system of transformer can be quantitatively described and the reliability of transformer can be obtained; Finally, transformer aging model is established to research the change rules of the transformer runnung state and determine the duration that the transformer stays in each stages of life. In addition, the application result shows the feasibility and effectiveness of the method above.

To study the performance of chitosan nanoparticles systematically, we characterized MMA, chitosan and synthesized chitosan nanoparticles by Raman spectroscopy. Through analyzing the characteristic peaks of each substance, we found MMA grafted chitosan by opening its carbon-carbon double bond. So Raman spectroscopy is a very effective way in terms of the characterization of nanomaterials .

By comparing research methods in the different disciplines of botany, military science and mathematics, in order to discover the phytocoenosium structure of urban green space, this paper induced a simple and practical method, which included four steps, i.e., quadrats selection, integrity indicators surveying, individual indicators surveying and type identification. This method applies to those research activities with less precision need and compact time.

Neighbor statistic algorithm is a kind of commonly used algorithm, statistical analysis was carried out on certain analysis value through the grid in the window, to reflect the local and zone terrain feature. This paper discussed the method of parallel algorithm based on neighborhood statistics serial algorithm parses and terrain algorithm. Focus on the data partition strategy and aperture effects processing strategy. Experiments show that, the two optimization method proposed can make the parallel program neighborhood grid processing algorithms make full use of parallel computing resources, and then further enhance its parallel performance on the general parallelization.

Principal Component Pursuit (PCP) recovers low-dimensional structures from a small set of linear measurements, such as low rank matrix and sparse matrix. Pervious works mainly focus on exact recovery without additional noise. However, in many applications the observed measurements are corrupted by an additional white Gaussian noise (AWGN). In this paper, we model the recovered matrix the sum a low-rank matrix, a sparse matrix and an AWGN. We propose a weighted PCP for the recovery matrix, which is solved by alternating direction method. Numerical results show that the reconstructions performance of weighted PCP outperforms the classical PCP in term of accuracy.

In order to test the feasibility of co-composting for surplus sludge and garbage RD thermal decompositing nutrient soil, the mid-temperature composting experiments for the optimized conditions such as bacteria inoculating mode, initial moisture and pH were carried. The results showed that:(1) K-bacteria isolated from soil had a ability of decompositing insoluble mineral potassium to soluble forms at a rate of 9.20 μgK/200ml.h, and a decomposing ratio of 7.83% for potassium feldspar in liquid batch culturing. Moreover, after liquid enlargement culturing for 32h, the quantity of bacteria spores reached its climax, which ensured the high survival rate of K-bacteria. (2) The pre-compost inoculating mode (M1) was superior to post-compost (5th d M2) based on available nutrient or K-bacteria quantity increasing;(3) Through optimizing experiments, the best initial moisture of 50-60% and pH of 6.5 were determined with an ideal available nutrients and K-bacteria quantity in compost; (4) The inoculating of K-bacteria could increase the microbial quantity and activity, which may increase the heavy metal activity in compost, so the further researches on heavy metal passivation should be considered.

This paper described the microstructure feature of the first short circuit and the second short circuit of copper wires in the electrical equipment line fire. The cause of fire is evaluated and analyzed by the difference in microstructure between the first short circuit and the second short circuit of copper wire. It would provide scientific and favorable evidence for the department of fireman to clear up a case of fire.

In this study we prepared a new rust conversion coating and examined its corresponding characteristics through a series of experiments. And at the end of the paper, we summarized the working mechanism of it. All the results may help to promote the development of rust conversion coatings and anti-corrosion science.

The reliability of power transformer is very important to the safe operation of the power system. So a new method for power transformer risk assessment based on FTA, FAHP and GA is proposed. The method firstly establishes the power transformer fault tree; Secondly, it analyzes the fault tree through Fuzzy Analytic Hierarchy Process and constructs the fuzzy judgment matrix on transformer fault factors; Finally, it changes the question of solving the weight coefficients of each factor into a mathematical programming problem, and uses Genetic Algorithms to get the result so as to obtain the transformer reliability. In addition, the application result shows the effectiveness of the method above.

The enclosed air plays a significant role in form-finding and loading analysis of ETFE cushions. A new numerical model of ETFE cushions is proposed in order to consider the interaction effects between outer membrane and internal air. Then the form-finding and loading analysis of a regular hexagon ETFE cushion are performed and compared with experimental study. It is shown that the numerical results are in good agreement with the test results. The interaction FE model can be used in static analysis of ETFE cushions.

External environment, information retrieval and productive process exist many uncertain factors.When making production plan,enterprises must take the uncertain parameters into account.This paper summarizes the characteristics of manufacturing network and define the node enterperise in manufacturing network;It discusses information uncertainty in manufacturing network and uncertainty in the process of production.It has in depth analysis of MRP formulation process under the environment.The perspective and methods of research on MRP has been given and it has certain enlightenment function for further research.

Globoidal Cam Indexing Mechanisms are used extensively as automatic tool changers (ATC) of machining centres or as indexing mechanisms in various machinery.By applying the theory of conjugate surface , the model for the surface design of the Globoidal Cam Indexing Mechanism of ATC is developed with MathCAD and Pro/E. The dynamic simulation of the me

This article described the operations of measurement, calculation and analysis of the cooling effect field of Shangcheng Park, the green space in Erqi Square Center of Zhengzhou City. This program is carried out in four steps. Firstly, the high-vegetation-quantity-area center was confirmed as the center point of the green space, and observation points and a reference one were also be identified. Secondly, field observation with instruments conducted and the data were kept records. Thirdly, Excel software was used to calculate the average daily temperature and the cooling rate of the green space. At last, analysis was given on the result of the operation. The results of Shangcheng Park study show that the cooling effect field of the green space has a radius of more than 60m, and distributes regularly.

To increase active property of aluminum anode material and decrease its corrosion rate, the effect of urotropine ((CH2)6N4) and saturated Ca (OH)2 environment-friendly additives on electrochemical behaviors of aluminum anode (99.999%) has been investigated by adding urotropine and saturated Ca (OH)2 into 4 mol/L KOH solution. The results show that additive urotropine ((CH2)6N4) can decrease the hydrogen-segregation and can increase activation property of aluminum anode greatly. With 1.0 % (w) of urotropine ((CH2)6N4) and saturated Ca (OH)2 addition in 4mol/L KOH solution, the corrosion current of aluminum anode becomes to minimum; its corrosion-inhibition ratio gets high to 87.3%. At the-1.20 V potential the current density of aluminum anode reaches to 37.7 mA.cm-2; the open circuit potential (Eocp) moves negatively and greatly to-1.815 V.

In order to detect the weak signal deeply buried in the noise, a weak signal detection system based on lock-in amplifier is proposed. The system includes the preamplifier circuit, active low pass filter circuit, AC amplifying circuit and phase sensitive demodulation circuit. Test results show that it can greatly increase the signal-to-noise ratio (SNR) up to 12.7db.

In this paper, combined with the approach bridge of cast-in-place continuous box girder project,discussion on the main bridge construction with support cast-in-place scheme design.The role of a great reference for large-scale projects,from the implementation of the index statistics, analysis shows that, to achieve even better than the specification requirements, and achieved the desired results.

For estimating seismic response of pier-structure under near-fault ground motion, The typical pulse-type near-fault ground motion records were chosen to establish a record base, and three pier models with different natural period were established; The non-elastic response spectral displacement of ground motion was used to estimate the nonlinear response; The yield displacement of the nonlinear oscillator was defined based on the static pushover analysis result, and its influence on response estimation was studied. The study result is important for structural seismic response estimation by using the non-elastic response spectral displacement and the probability-based seismic performance evaluation.

For projects, especially large-scale projects, due to the long time of project construction, the construction of the complexity of the geological conditions, sometimes inevitably lead to quality defects.How scientific and reasonable quality defects hidden works to take remedial measures, or effective correction to restore the loss of time, cost, quality, safety,become an important engineering problem.Some cracks, will not have a substantial impact on the project, you can take measures to deal with to ensure proper implementation of the project.The article takes the analysis of crack initiation and Treatment in the Suining two station project.There are a lot of reference in processing defects in the country's large projects.Statistical indicators from the implementation of the results, analysis shows that to achieve even better than the regulatory requirements, and achieved the expected results.

With wind tunnel tests, simultaneous pressure measurements are made on 4 cylindrical roof models with different rise-span ratios and roof inclinations. Effects of these geometrical factors on wind pressure characteristics of the roofs are investigated, including mean pressure coefficients, RMS pressure coefficients, skewness, kurtosis, and probability distributions of wind pressure. Results show that the mean vertical wind force coefficient of high rise-span ratio roof is larger than that of the low rise-span ration roof; the mean pressure coefficient distribution of the low rise-span ratio roof is similar to that of RMS pressure coefficients and the skewness (or the kurtosis); the vortex center line occurs at the windward edge for the low rise-span ratio roof with inclination 0°, which occurs at the roof apex for the high rise-span ratio roof. The roof inclination has more effects on the low rise-span ratio roof, the vortex moves from the windward edge to the apex for the roof with inclination 7.2°when the wind flows from the low eave to the high eave. The distribution of the skewness is strongly correlative to that of the kurtosis. The probability distributions of the roof edges and corners deviate obviously from the Guass distribution. If this point is ignored, the peak suction pressure will be underestimated.

A precision temperature control system that uses ATmega128 as the main control microcomputer is built. The temperature is sensed by a Pt100 thermistor, and then converted into the voltage signal by a temperature transmitter to the microcomputer. Two kinds of digital PID (Proportional-Integral-Differential) algorithms are adopted to control the output power of the thermo-electric cooler (TEC) automatically. The test results of the improved temperature control system show that the set-up time of this system is about 340s and the temperature control accuracy is up to±0.1°C.

In this paper, air Anions functions such as cleaning air, resisting bacteria, health care and the seven evaluation criteria system of the air anions concentration were introduced. Air Anion Concentration of Riyuexia National Forest Park in Heilongjiang province was Measured and analyzed. After comparing the result of 10 samples to the Anions evaluation system we can see that the air quality of Riyuexia National Forest Park is very fresh, it helps to health and is fit for some ecotourism activities such as health preservation of forest and fresh air bath. The paper proposes that we should preserve forest and water tourism resources, construct featured green eco-system and publish air anion Concentration index regularly.

In this paper, air Anion and its functions such as cleaning air, resisting bacteria and health care are introduced. Beidaihe where is located at sea and near Beijing is a famous place for people to live and travel.Through measuring air Anion concentration of Beidaihe and comparing the result to the seven evaluation criteria system of the air anions concentration, we can see that the air in Beidaihe is very fresh, it helps to health and is fit for some eco-tourism activities. Coming to a conclusion that Beidaihe is the best city to travel and keep healthy.

In this paper, the micro-nanopowder of ancient Sea rock was used as core material to filter tap water. With this method, the healthy-drinking water has been prepared successfully with the property of weak alkaline, small molecule clusters, rich of trace elements contributing to health. Its properties were characterized by high-resolution superconducting NMR spectrometer, inductively-coupled plasma spectrometer, far infrared radiation rate tester, pH acidity meter and redox potential instrument. The results showed that the pH value of this water was 7.2~7.8, and the region of ORP was 124mV; FWHM of 17O-NMR spectrum was 56.39Hz, It is a kind of water with small molecules; It also contains a variety of macro and micro elements which human needed; The filtered water is beneficial to human health and longevity with a good immune function. Keywords: Ancient Sea rock, Function water, Health, Longevity

The 4,4-diphenyl methane diisocyanate (MDI), polyethylene glycol (PEG) and epoxy resin (EP-44 and EP-51) were selected to prepare series of water polyurethane modified by epoxy resin (EWPU) by using chain extender, catalyst, and neutralizer. The influence of such factors as the R (NCO/OH), the contents of DMPA and epoxy resin on the performance of emulsion and film were discussed in details. The results shows that when R was 1.7, DMPA content was 7%, epoxy resin content was 8%, the EWPU emulsion appears brilliantly and shows great stability, it was measured that the water absorption, tensile strength and breaking elongation of the film are respectively 8.41%, 15.52MPa and 318%. Moreover, the comprehensive performance of the WPU modified by E-44 is better than that modified by E-51. According to the FTIR analysis, the EP has been successfully introduced to the waterborne polyurethane molecular chain.

This article describes the preparation process of the anion acrylic and its test. In this study, using natural mineral nanomaterials prepared anion additives, using a two-step prepared anion acrylic fiber. Has been tested, the anion acrylic the indicators are good, the anion release can reach 1430 anions / cm3, and can be widely used in clothing, textile, medical and other fields.

A kind of installation used to push the sand out of railroad consisted of railway sand pushing installation and railway turnout sand blowing installation. The installation can be set on the pre-panel of the rail car or patrol and check vehicle; which can be used for quick extrusion the sand on the railway and blow out the sand in the railway turnout. Thus the train can run in gear when the railways are covered with a lot of sand. So we can solve the problem that the train is blocked by the sand on the railway. Keywords. Railway installation, Railway sand pushing installation, Railway turnout sand blowing installation, Railway sand cleaning installation.

This paper described the inspection device of temperature control in data acquisition, data storage, display and other functions and development methods, a through instances of the application data logger in fire simulation test. Its application of development methods and program can be used in other similar project. Thus a reference has been provided for them.

Pyroelectric sensors based on PVDF polymers have great potentialities in the practical areas because of their great merits in the high converting efficiency from caloric or kinetic energy to the electric signal, as well as light-weight and flexibility. This work emphasized on the simulation of the PVDF pyroelectric sensor on the circuit level. The presented equivalent circuit model was simulated with the combination of the whole testing circuit in the environment of Multisim, so the simulated data could be comparable with the measured ones. And the validity of this PVDF sensor’s Multisim model was testified by the comparison with experimental data. Moreover, thermoelectric energy conversion was discussed by the extracted parameters in the equivalent circuit.

The main steam temperature of the boiler adopted usually a cascade PID control. Traditional PID parameter engineering tuning method has a very high demand for the control personnel. And the control loop of inner and outer ring interacted. Adjusting wasted the time and labor, and the control effects were difficult to achieve the optimal. Adopting the ant colony algorithm can optimize Cascade PID controller parameters. A combination of multiple parameters was the ant colony's foraging path, and the moment integral of absolute error was the optimization objective function, through the simulation for an ant foraging process, the optimal combination of parameters was identified. The simulation results showed that the main steam temperature cascade PID controller based on ant colony algorithm has good control effect.

Finite element method (FEM) is applied to analyze the buckling performance of alloy aluminum stiffened panel subjected to uniform axial compression. With the skin thickness and stiffener pitch unchanged, the influence of flange thickness, flange length, stiffener thickness and stiffener height on compress buckling critical loads are studied by FEM. Important parameters influencing the buckling performance are identified and the results offer a referenced measure for the optimization design and engineering application of the structure.

Two equivalent models based on sandwich panel theory and equivalent panel theory were discussed in this paper. By analyzing the performance of fiber - paper honeycomb sandwich structure compound panel by bending load, the computational results are in accordance with test and Engineering software ANSYS. Therefore, it shows that the finite element equivalent models are reasonable and practical for the optimization design of fiber - paper honeycomb sandwich composites.

Comparative molecular similarity indices analysis (CoMSIA) were performed on N-dichloroacetyl oxazolidine derivatives as herbicide safeners. The best CoMSIA models that were generated using atom based alignmen, Rcv2=0.632, n=4, R2=0.927, F=31.796 and s=0.097. The contributions of steric field, electrostatics field, hydrophobicities field and hydrogenbond acceptor were 0.127, 0.260, 0.285 and 0.328, respectively. The CoMSIA model was satisfactory and would be useful for the future design of new N-dichloroacetyl oxazolidine herbicide safener.

On the basis of the CT mountings’ technology characteristics produced by Furan resin self-hardening sand, and aiming at the easy appearing defects in the progresses, the reasonable solution had proposed. Practice has proved that, through the scientific selection of raw and auxiliary materials, controlling the molding the environment conditions and strict management of key processes, can improve product quality to meet customer needs.

Finite element method is applied to analyze the buckling performance of composite stiffened panel. Compress buckling critical loads of six types panels with T or Z-section stiffeners are calculated by FEM. The emulational calculation results show that with same cross section area, critical buckling load of panel with T-section stiffeners increases with the reduction of stiffener pitch and the increase of stiffener numbers, while the buckling load of panel with Z-section stiffeners increases to a certain level and then keep almost changeless. To T-section stiffener panels, the relation between thickness of skin and buckling load is approximately quadratic trinominal. Conclusions obtained can offer a referenced measure for the optimization design and engineering application of the structure.

Considering the structure type of the steel staggered-truss (SST) system, the effect of infilled walls will be major and need to be studied amply, some scientific design regulations need to be found for referrence. Based on two different 3D models considering or ignoring the stiffness of infilled walls (SIW), a numerical investigation is presented on the structural behaviors of the SST system utilizing the finite element 3D simulation analysis soft ware ETABS. The longitudinal structure is asymmetrical due to the SIW, it causes the torsion forces in the building. Comparing to the different results of response spectrum analysis, including storey drift and equivalent base shear under frequent earth quake and rare earth quake, some conclusions were made, including the capacity of the SST system under seismic load and the effect of the SIW for SST system. The increased base shear force factors due to the effect of the SIW were suggested for SST structure design, it is different from the other steel structure types.

Continuous cooling transformation (CCT) diagram of steel 22MnB5 was studied using dilatometer method. The influence of the hot forming process parameters, such as the heating temperature and holding time on the mechanical properties and microstructure of stamped parts was analyzed by tensile tests and the metallographic observation on the parts with various processing parameters. The microstructural evolution obtained from the dilatometer samples reveals that the cooling rates not smaller than 20K/s induced fully martensitic microstructure. As the cooling rate decreasing, more ferrite and pearlite or more bainitic microstructure forms. Tensile tests results show an excellent tensile strength and ductility combination of 22MnB5. The tensile strength and yield strength reach 1500MPa and 1200MPa respectively, with total elongation of around 10%.

In order to improve the experimental evidence of hotoinitiator, the effects of various dose of photoinitiator on mechanical properties of nanohydroxyapatite composite were investigated. According to the light initiating system, CQ and DMAEMA accounted for 0.8wt％, 1.0wt％, 1.2wt％ of total resin matrix, respectively. And then NHA processed by KH-570 was mixed with resin matrix in the ratio of 55:45. Then three groups （A, B, and C） of light-cured nanohydroxyapatite composites were prepared. Karuisima composite resin was used as control group D. The cured depth, compressive strength, and flexural strength were determined in each group. The results showed that as the ratio of photoinitiator increased, the cured depth increased, while the mechanical function declined. In group B, there were no significant differences in compressive strength, and flexural strength as compared with control group,P>0.05. It is suggested that the quantity of CQ and DMAEMA in resin matrix were 1.0wt% respectively, the new light-cured nanohydroxyapatite composite has good qualities in both cured depth and mechanical property.

During the construction for solving geological hazard of landslide, there often existed the accidents of sticking pipe and burying drilling caused by borehole collapse. It resulted that drilling tool couldn’t be pulled out, and scraped the drilling tool and borehole. So it was necessary to research a kind of pneumatic hammer which could realize drilling at normal work, and push out the drilling tool by reverse impact when the formation collapse caused sticking pipe and bury drilling. In order to research profoundly the pneumatic hammer work mechanism and describe piston movement laws in detail, physical model was established according to the actual conditions, finite difference method was adopted, thermodynamics and kinematics were applied. Using object-oriented programming, the bidirectional pneumatic hammer software was developed whose integrated development environment was VB. The software could calculate acceleration, velocity, displacement, pressure, temperature of the front and back air chamber at any time and the operating performance parameters of the pneumatic hammer. Not only the bidirectional pneumatic hammer, but also the unidirectional pneumatic DTH hammer and the no-dig impactor were designed by the software.

The mechanical behaviors of intersecting joints considering damage accumulation in steel tube structures is analyzed through the FE-program ABAQUS. The stress characteristic and failure modes of these joints are concluded. Especially, it has been analyzed influence of the change of geometric parameters to mechanical behavior of joints. Finally, the results indicate the joints have a good mechanical performance and good plastic deformation as to excessive local buckling of chord under the loads.

Chemiluminescence immunoassay (CLIA) is the combination of chemiluminescence system and immunoassay. CLIA is established as one of the best alternatives to conventional radioimmunoassay for the quantitation of low concentrations of analytes in complex samples. A high-performance CLIA control system based on the embedded microprocessor S3C2410A is presented in this paper. The system principle, the overall structure of the system, the control structure of the key functional blocks and the flow chart of the software are given. The hardware drivers and the application software are developed on the basis of S3C2410A. The experimental results show that the presented system is feasible in the clinical diagnosis and can be used in the automatic chemiluminescence immunoassay analyzer.

According to the strain energy equivalent, the resonant response equivalent static wind load of large span roof is derived. It solves the matter that should consider numerous structural response control objects on calculating equivalent static wind load for large span roofs, and establishes relationship with the structural strain energy introduced by fluctuant wind loads. Finally, the method is used to resonant equivalent static wind load analysis of 2008 Beijing Olympic Tennis Center Stadium roof structure. The results illustrate that the method proposed in this paper is effective and the precision is reliable.

Based on strain energy equivalent, the background response equivalent static wind load of large span roof is derived. It solves the matter that should consider numerous structural response control objects on calculating equivalent static wind load of large span roofs, and establishes relationship with the structural strain energy introduced by fluctuant wind loads. Finally, the method is used to background equivalent static wind load analysis of China National Stadium roof structure. The results illustrate that the method proposed in this paper is effective and the precision is reliable.

The theory of natural frequencies were acquired from vibration experiment, meanwhile, the first order frequencies of honeycomb sandwich structure composites were obtained by using the sandwich laminboard theory and equivalent panel theory via the finite element software ANSYS. The simulation results were compared to the experiment results to get the error of calculation of the two different equivalent methods, thereby we can select more appropriate equivalent method to ensure the veracity of the result analysis and provide a reference for the optimization design of the fiber-paper honeycomb sandwich structure composites.

An in-site measurement method for big gears based on laser tracking and coordinate measurement technology is proposed in this paper. The coordinate transformation method, in which direction cosine are used as parameters, is suitable for large rotation angle transformation. The coordinate transformation with large rotation angle in the in-site measurement, hence, can be realized. The experimental results show that the proposed coordinate transformation method has the advantages of high accuracy and stability, and can meet the requirements of the laser tracking in-site measurement system for big gears.