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The mold clamping mechanism is an important mechanism of injection machine, and the mold clamping mechanism with good kinematic characteristics is the goal pursued when designing injection machine. Traditionally, the mold clamping mechanism must have at least one toggle effect at clamped position; when the mold is at open position, the mold clamping mechanism does not need to have toggle effect. In this paper, 2 mechanisms of existing patents are used to illustrate the process of the dimensional synthesis and kinematic analysis of mold clamping mechanism with double toggle effects at clamped position. The kinematic characteristics of 2nd mechanism is better than 1st mechanism.

The Electron Beam Melted (EBM) method is one of the attractive attention thing additive manufacturing methods. By using an EBM additive manufacturing method, CP Ti and Ti-6Al-4V specimen were fabricated with a certain processing parameters. The mechanical properties such as fatigue limit, tensile properties including microstructural characteristics of CP Ti and Ti-6Al-4V specimens fabricated by EBM were confirmed and were compared with the conventional Ti alloys. Additive manufacturing was obtained high strength by creating martensite due to rapid cooling. On the other hand, void occurrence cannot be avoided by the method of using powder, accordingly it had a low fatigue strength value. Therefore, this study focused on that the values of fatigue characteristics of the EBM specimens and conventional specimens were compared and analyzed. EBM CP Ti had good mechanical properties such as yield strength, ultimate tensile strength, elongation and fatigue limits, approximately as same as casting CP Ti. EBM Ti-6Al-4V showed good mechanical properties, but fatigue limits were lower than wroughtTi-6Al-4V. That resulted from the formation of several kinds of internal pores which caused to increase the crack initiation and propagation.

In order to reduce the variation of suspension parameters during wheel runout, andimprove the handling stability of the whole vehicle, a method for optimal design of Torsional beamsuspension structural parameters based on Multi-island genetic algorithm is proposed. Study on theMacpherson Front suspension of a car, based on the Euler's four-element method of multi-bodydynamics and the spatial analytic geometric transformation formula, the mathematical model ofTorsional beam suspension is derived in this paper, the reliability of the mathematical model isverified by the simulation analysis of the corresponding Adams model. On this basis, the degree ofsuspension performance affected by structure parameters is obtained by Sensitivity analysis. Finally,the optimization of suspension performance is realized by modifying the parameters by usingMulti-island genetic algorithm, which plays an important role in the stability and safety of thewhole vehicle.

As small wind turbines are increasingly used, the assessments of power quality may thus become paramount. Unlike the large-scale wind turbines which are optional required to perform power quality measurements during production certification stage; however the power quality measurements are often neglected in small wind turbines since they are not requested on the certain of national grid codes at low-voltage distribution system level. Considering the high penetrations of small wind turbines may be connected to the future urban electric network, the paper performs the power quality on-site measurements of a horizontal axle small wind turbines. The issues may include the discussion of measurement system structure, the description of measurement method, and the analysis of wind turbine power characteristic, voltage/current trends, harmonics and flicker phenomena. The measured data collected in the study will valuable for the further analysis of power systems connected with the small wind turbines.

Due to the reasons of manufacture cost and mechanical efficiency, the gear transmissions for electric vehicles are helical gear reducers. For electric vehicles, the reduction ratios are required to be 11~30 and their gear reducers are helical gear reducer with two gear pairs. This paper focused on the design and prototype manufacture of helical gear reducers with two gear pairs. First, according to the kinematic requirements of electric vehicles, their reduction ratios were derived. Then, based on the involute theorem, the gear data of helical spur gear pairs we obtained. Finally, according to the gear data, its corresponding engineering drawings were accomplished and its corresponding prototype was manufactured. The results of this paper can be used as reference for engineers to design the gear reducers for electric vehicles.

An elastic-plastic contact stress analysis is presented to study cyclic plastic deformation of rolling elements under repeatedly contact loadings. The rolling contact is simulated by a Hertzian line contact loading translating over the surface of an elastic-plastic half-space, and the Chaboche nonlinear hardening rule is used to model the cyclic plastic behavior of contact components. A finite element procedure based on the return mapping algorithm is implemented to analyze the evolution plastic strains and residual stresses versus contact cycles. For the contact loading below the shakedown limit, p0/k=4, the plastic deformation occur only at first few contact cycles and become pure elastic in the subsequent cycles due to the existing residual stresses and material hardening. For the contact loading exceeding the shakedown limit, p0/k=7, the plastic strains increase progressively with each pass of contact cycles and result in plastic ratchetting. The normal residual stresses, however, quickly reach a steady state after few contact cycles.

A multi-material, multi-layer dome structure is proposed for desigining futuristic body protection pads that will address a safety issue prominent among the population of elderly people, patients, industry workers, military personnel, and sport players. Those people are prone to be subjected to blunt impacts due to falls, bullets, and blast waves, which can result in serious injuries, early death, and extremely high medical costs. Protector pads can effectively reduce impact force and prevent injuries in high-risk individuals. However, most currently available protection pads are bulky, heavy, or rigid. Therefore, new body protectors need to be developed to satisfy the requirements of wearing comfort, ease of fitting, ensured protection, and cost-effectiveness. Out of many different design ideas generated, the most promising ones were identified through an evaluation process based on various criteria such as performance, comfort, and manufacturability. One of those designs utilizes a dome-shaped top layer and thin fabric membrane component that is very strong in tension but flexible in bending. Such structure will make the pads excellent in dissipating shock energy by diverting normal impact force to lateral direction and minimizing the force directly transmitted to the weakest body parts. Through finite element analyses, the best combinations of materials and components were identified. The selected pad structure was optimized for light-weight and flexibility while keeping excellent resistance to the compression. The thickness of the shell element and the overall thickness of the whole pad were optimized for the same level of deflection and stress as other simple shell pads. The results showed that the dome-shaped structure could be a useful component of effective body protection pads through optimal combination of various materials and layers.

This research focuses on influence of pore structure on chloride distribution in surface layer of cement paste under cyclic wet-dry condition. The results of chloride distribution reveal that drying and wetting cycles can lead to a peak value of chloride content (Cmax) occurring in surface layer of cement paste. Cmax increases with the increase of W/C. While the depth (Δx) at which Cmax appears does not show a regular change. Moreover, Cmax should be used to predict service life of concrete structures when Cmax appears in the chloride profiles. For the influence of pore structure, there exists an obvious hyperbolic relationship between chloride diffusion coefficient (D), Cmax and pore structure parameters. D and Cmax increase with total porosity and the most probable pore diameter, decrease with tortuosity, and stabilize gradually. And the most probable pore diameter has the most significant impact on D and Cmax. In addition, XRD and SEM-EDS results indicate that the deposition of Friedel’s salt results in the formation of more inkbottle shaped pores, which may cause the appearance of Cmax under cyclic drying-wetting conditions due to hysteretic moisture effect.

Nano-filler reinforced epoxy composites has been investigated in this study subjected to various mechanical and pin-on-disk tribological tests. Two different types of nano-filler were used namely, rigid nano-silica (SiO2) particles and soft nano-rubber particles. Incorporation of nano-filler in polymer matrix enhance mechanical properties. In addition, tribological response of composites are also better compared to neat epoxy polymer. However, the effect of nano-silica addition is much more pronounced than that of nano-rubber due to the high rigidity of nano-silica reinforced epoxy composite. This was mainly attributed to transfer film layer (TFL) formation. The TFL was further investigated by electron microscope and nanoindentor. The best set of tribological properties was achieved at 8 wt. % nano-silica addition. This was due to better reinforcement dispersion and continuous transfer film layer formation which eventually control the overall friction and wear mechanism.

Resource consumption, energy consumption, environmental impact and costs of layer-combustion boiler were assessed by using life cycle assessment (LCA). The costs during construction stage, resource and energy consumption during operation stage of layer-combustion hot-water boiler were focused on. Life cycle inventory was established. The results show that: throughout the boiler life cycle, the largest resource consumption indicator is that of coal with value of 93%, followed by natural gas and limestone. For the internal costs, although operation costs are obviously higher than construction costs, the construction costs still account for more than 30%, which is related to the relatively short servicetime of layer-combustion heating boilers. For the external costs, global warming accounts for the highest proportion.

In order to solve the problems of the easy breakage, transport problems and pile holes shrinkage, a sleeve piling machine was designed. It included a fully used pile frame, a novel pile driver and its piling method. The piling machine integrated the advantages of the diesel hammer piling machine and the vibration hammer piling machine. It is suitable for bored piles and compacted piles. Based on the sleeve pile tubes, the diesel hammer and the vibration hammer worked together to drill. Then the reinforcing cage was lifted by the hoister, the pile tubes were pulled and the concrete were poured with the help of the vibration hammer. All of them can avoid the shrinkage of the pile, the break of the pile, and improve construction efficiency. Besides, finite element analysis of the pile tubes were calculated by ANSYS, the results showed that the strength of the pile tubes was satisfied with the requirements of application. The piling machine and the method were feasible.

Aluminum foam sandwich structure is a new type of composite material with excellent mechanical and functional properties. As it is known that properties of aluminum foam sandwiches (AFS) vary if the foam core is sandwiched between different face sheets. To study the effects of face-sheet materials on the mechanical properties of AFS and enable a better understanding of the usage of such AFS structures under flexural load, AFS sandwiched by 6061-aluminum alloy face-sheets and 304 stainless steel face-sheets were fabricated and investigated under three-point bending by using WDW-T100 electronic universal tensile testing machine. Results showed that 6061-aluminum alloy reinforced AFS had the same peak load value with 304-stainless steel reinforced one almost so long as the thicknesses of the face-sheet material were the same and the foam core densities were the same too, but the energy absorption ability of 304-stainless steel reinforced AFS was much higher than that of 6061-aluminum alloy reinforced. However, the integrality of the 6061-sandwiched AFS was better than 304-sandwiched AFS. Deformation modes of the two types of AFS were also discussed in the present study.

This study aims to review variation pattern of moisture content ratio of grains in deep-bed drying process, guide the drying technology design, realize real-time tracking and regulation in drying process, improve the quality of drying process and reduce energy consumption. Based on the moisture diffusion model in thin layer drying process, the principle of mass conservation of deep drying process, state function and irreversible thermodynamics analytic method, we have established and solved basic equations of deep-bed drying of grains, obtained the moisture content ratio of grains and analysis formula of drying velocity distribution in processes of concurrent flow drying, counter flow drying, cross-flow drying and standing drying and resolved the sustained decreasing drying process of grains in the concurrent flow drying and extreme point of drying rate in the counter-flow drying. Under the same conditions of temperature, humidity and air output, the drying velocity in counter-flow drying significantly higher than that in the concurrent flow drying. It means the energy utilization effects in counter-flow drying is better than that in the concurrent flow drying. Drying characteristics of grains in cross-flow drying and standing flow drying are the same, while drying rates in inlet-air side and outlet-air side vary widely. It means that when the layer thickness is 0.5m and the moisture content is over 20%, the drying rate in outlet-air side is nearly zero and the drying uniformity is bad. Tests on 5HP-3.5 recirculation drier shows that maximum deviation between analytic value and measured value in deep drying process is 0.69% and the range scope is -0.27%-0.69%. From the drying characteristics of grains, deviations mainly come from instrument detection deviations. The analytic method has important significance for realizing real-time tracking and regulation in drying process, guiding drying technology design, reducing energy consumption, increasing drying rate and drying machine capacity.

The cleaning efficiency of EO (ethylene oxide) 8~9 mole was about 78-80%, it is the best. The highest cleaning efficiency for each EO mole concentration is as follows. The cleaning efficiency was 97% in the surfactant of 4.8% EO 5 mole, the cleaning efficiency was 97% in the surfactant of 7.7% EO 8 mole, and 68% in the surfactant of 7.7% EO 10 mole. The cleaning efficiency was measured using a surfactant with various EO mole. All detergents were tested at 20% surfactant concentration and EO 8 and EO 9 showed the highest cleaning power. In experiments using 8 mole of EO surfactant NPE8, the highest cleaning power was obtained at surfactant concentration of 7.7%. To determine the cause of this, the electrical conductivity of the solution was measured at the concentration of NPE8 at 1.6%, 4.8%, 7.7%, 14.4% and 20%, respectively. After washing the test plate with NPE8, the detergent remaining on the surface of the test plate was analyzed by FT / IR, and it was found that the detergent did not remain.

This paper discusses the use of centralized control method in an Intelligent Energy Management System (iEMS) to prevent voltage violation after load transfer between distribution feeders with high PV penetration level. The proposed method comprises three control modes with different control algorithms for regulating both reactive and active power output of PV inverters in a distribution system with multiple PV installations. Before the execution of load transfer, the total reactive power compensation required at the critical Point of Common Coupling (PCC) is solved by the reactance of distribution feeder line segment to prevent system voltage violation. With the proposed control algorithms, the iEMS dispatches total reactive power compensation among PV systems according to the reactance of line segment and issues the control command to each PV inverter for adjustment of PV power generation so that the ancillary service of voltage support can be provided by all PV systems in a fairer manner. A practical Cimei island distribution feeder pair is selected for computer simulation to verify the effectiveness of the proposed control method after load transfer between two feeders.

This study proposes a Mahalanobis Distance Measurement (MDM) method to analyze current waveform for determining the motor’s quality types. The MDM method consists of three major stages: (i) the preprocessing stage which is for enlarging motor current waveforms’ amplitude and eliminating noises, and includes signal amplitude amplifier, filter circuit (eliminating noises), and analog-to-digital converter (ADC) parts, (ii) the qualitative features stage which is for qualitative feature selection on motor current waveforms, and (iii) the classification stage which is for determining motor quality types using the MDM method. It can recognize defective motors and their defective types in less than 0.5 second. In the experiment, the total classification accuracy (TCA) was approximately 99.03% in average. The proposed method has the advantages of good detection results, no complex mathematic computations, hi-speed, and hi-reliability.

This paper develops a digital measurement and control technology of grey predictor-based inverse hyperbolic sliding function for solar PV inverters. The advantage of inverse hyperbolic sliding function (IHSF) is very low sensitivity to system uncertainties. However, when a large parameter variation or a sudden external load interference is applied, the steady-state errors still occur in the IHSF controlled solar PV inverter and incur high total harmonic distortion (THD), even deteriorate control accuracy. To eliminate steady-state errors, a grey predictor is used for the prediction of voltage THD. Once a high voltage THD of the solar PV inverter output is detected and then measured by grey predictor, the tracking error of the IHSF controlled system will gradually decrease to zero, thus achieving zero steady-state errors. With the proposed measurement and control technology, a digital closed-loop solar PV inverter system will yield high-quality AC output voltage with low THD and fast dynamic response even under highly nonlinear loading. Experimental results for the solar PV inverter are performed in support of the proposed technology.

Rotor axis orbit measurement of the spindle under cutting process is the important basis of cutting quality judgment and spindle fault diagnosis. In the cutting process, the non-stationary characteristics of vibration measurement signal of spindle rotor has been particularly outstanding, under such circumstances it is difficult to draw spindle rotor axis orbit accurately. To solve this problem, a new method using EEMD (Ensemble Empirical Mode Decomposition) and harmonic wavelet is put forward to realize non-stationary signal purification and rotor axis orbit feature extraction under machine tool spindle cutting process. In order to filter out the high frequency noise of the measurement, the EEMD method has been used, in addition that the characteristics of the original signal is preserved well. However the signal after EEMD filter still contains a variety of frequency components, in order to solve it, the harmonic wavelet method is used to decompose the signal into several signals according to the different frequency components, through the signal reconstruction achieve rotor axis orbit feature extraction. Using this method, the machined workpiece has been cut under the speed of 12000r/min, the vibration of spindle has been measured and processed. The experiment results show that the new method can effectively reduce the high frequency interference noise signal, and also apparently the rotor axis orbit obtained is more clearly than the original rotor axis orbit.

In this paper, graphene nanosuspension was spray deposited using electrohydrodynamic atomization (EHDA) technique, and the polydimethylsiloxane (PDMS) was used as the substrate during the EHDA process. The effect of the PDMS substrate before and after oxygen plasma treatment on the characteristics of EHDA was examined. A cone-jet mode of the EHDA of graphene nanosuspension was obtained using the oxygen plasma treated PDMS substrate. In addition graphene films were deposited on the oxygen plasma treated PDMS at different working distances. The lowest sheet resistance of the graphene films is 127Ω·sq-1. Furthermore, graphene lines at the range of 30μm-170μm were fabricated using the template assisted EHDA deposition method.

The accurate measurement of labor productivity data can mean the difference between the success and failure of a building construction project. Due to the sheer diversity and complexity of international building construction practices, minimal research has been performed on comparative labor productivity between countries. In this paper, the authors present a research project that was conducted by comparing the Chinese labor productivity with the U.S. labor productivity in building construction projects. The labor productivity data were collected from different jobsites in the U.S. and China by using a time-study method with established data collection procedures. Furthermore, work sampling in the HVAC system work category was used as a method to gather information about the amount of labor productive and nonproductive work hours spent on construction activities. It is certain that there are many factors affecting productivity in the building construction process. With the lack of timely and effective project quality supervision, construction quality cannot be guaranteed. For this reason, various statistical analysis methods were applied to analyze and compare the collected productivity data from both countries. Findings of this productivity comparison can provide industry practitioners the advancement of knowledge in the Chinese building construction industry and it can support benchmarking and continuous improvement of productivity with a greater efficiency in both the US and Chinese building construction markets.

The smaller envelope of space manipulator system is often required during the launch phase, while the lager range and higher precision for operation is needed in the space application stage. It is difficult for a single manipulator to meet the above requirements. To solve this problem, a self-reconfigurable space manipulator system with telescopic rod is proposed. When the manipulator is in the contracted state, the envelope is small and the operation precision is high; however, when the manipulator is in the extended state, it can reach a large operation range. This paper presents a equal-section arm telescopic mechanism，which can realize the extension and contraction of arms by the horizontal strip and the vertical strip being engaged and locked with each other. And the parameters of the telescopic mechanism and the stiffness of the rod are analyzed and simulated，which shows that it has the characteristics of high stiffness and high telescopic ratio. Finally, aiming at the target operating conditions in the narrow space, the manipulator motion planning simulation analysis is carried out. The simulation results show that the design of the equal-section telescopic rod can improve the adaptability of the space manipulator system.

Driving axle loader is a key component for loader. For the steering drive axle of the QAY125 all terrain crane, the main parameters of the main reduction gears and drive axle housing have been designed and calculated. By adopting the method of optimum matching between engine and transmission system parameters, the ratio of the main reducer is determined by the optimum design. Considering the drive axle housing structure and the force is very complex, in order to ensure the strength of full static strength check calculation of impact load and emergency braking of the three cases, calculations show that the axle strength design can meet the design requirements. The half shaft diameter is calculated by using the maximum torque, when the half shaft diameter is 45mm, the material selection 42CrMo, the half shaft safety factor is 2.09, completely meet the use requirements.

There are a series of problems in using explosive source in land oil seismic exploration at present. Aiming at this problem, a new hammer source system which can replace explosive source was proposed. Function of the hammer source system was analyzed and a typical pneumatic control circuit was designed. With the advantages of strong impact, high speed and small gas consumption, quick air exhaust impact cylinder was used in the hammer source system. An electronic control system was designed based on PLC, including the hardware component and software design. The pneumatic control system was simulated and analyzed in AMESim, and the results showed that the system can meet the design requirements, provide a reference for engineering application.

Thermo-gravimetric technology was used to rapidly evaluate and measure safe use life of food contact polymer materials. The thermo-gravimetric curve showed that silicone rubber pad decomposition temperature was about 350°C in air and the maximum decomposition rate was 450°C. 370°C, 380°C, 390°C, 400°C, 410°C at the right temperature zone was chosen to do thermo-gravimetric constant temperature experiments; the time of silicon rubber pad’s weightlessness of 5%, 10% 15% was calculated by the above curve, respectively. Finally Arrhenius equation was used to establish the relationship between temperature and time; and then the result of infer silicone rubber pad using life was 1.37 thousand times when it was used as a baking tray.

Semi-submersible permeable tetrahedron is a new wave consumption structure. The design concept of the model structure is that on the premise of ensuring the natural landscape are not destroyed. Structure completely infiltrate below sea level is called semi-submersible wave structure. In this paper, based on the physical model, the transmission coefficient of this wave consumption structure under regular wave were got, and the effect of the wave period, wave height, model height, rows’ number of layout and other factors on the attenuation characteristics of Semi-submersible permeable tetrahedron were investigated. The research results show that Semi-submersible permeable tetrahedron performs better wave dissipation on both long-period waves and short-period waves, which has wide prospect in application.

With the continuous development of social economy, China's port construction scale has become saturated. As an important part of the harbor, the breakwater plays a crucial role in the safety of the working environment in the harbor, and the reliability of the breakwater is an assessment of its safety. Build on the previous studies, this paper puts forward a semi-submersible breakwater using waste tires. The reliability of this breakwater is analyzed by Monte Carlo method of artificial neural network based on Matlab, and the results are compared to those of Direct sampling Monte Carlo method and Important sampling Monte Carlo method. The results show that the Monte Carlo method is able to analyze the reliability of overturning failure of semi-submersible breakwater of waste tire. Compared with the other two consequences, the result is more accurate. The Monte Carlo method of artificial neural network based on Matlab has the obvious advantage in being devoted to the problem of complex structure and variable. Safety of the breakwater meets the relevant requirements and can be applied to the actual engineering. It can be seen that waste tires has a high degree of reliability, daptability, and a wide range of applications.

The red phosphor (TiZn2O4) is formed from TiO2 and ZnO via simple solid-state reaction. This red phosphor is prepared by chemically stable as well as inexpensive oxide materials. Emission and excitation spectra are investigated for this phosphor. Photoluminescence (PL) measurements reveal that this phosphor emits bright red emission at 611 nm, which is associated with 5D0 – 7F2 transition, with near UV (395 nm) and blue light excitation (470 nm). The measured decay time of this red emission can be fitted well with a fast decay time of 67 ms and a slow decay time of 208 ms, respectively. A broad grain size distribution is observed for TiZn2O4 phosphor. Further, photoluminescence excitation (PLE) shows a good absorption band near UV, and the blue spectral region of visible spectrum as well. The optical properties, X-ray diffraction (XRD) measurements, and scanning electron micrographs (SEM) of this TiZn2O4 phosphor are studied.

The importance of environmental consequences due to diverse substances that are emitted during the production of concrete is recognized, but environmental performance tends to be evaluated separately from the economic performance and durability performance of concrete. In order to evaluate concrete from the perspective of sustainable development, evaluation technologies are required for comprehensive assessment of environmental performance, economic performance, and durability performance based on a concept of sustainable development called the triple bottom line (TBL). Herein an assessment method for concrete eco-efficiency is developed as a technique to ensure the manufacture of highly durable and eco-friendly concrete, while minimizing both the load on the ecological environment and manufacturing costs. The assessment method is based on environmental impact, manufacturing costs, and the service life of concrete.

The countries around the world have developed and operated systems which assesses the environment-friendliness of buildings. The levels of certification systems differ to the circumstances by countries such as weather conditions and natural features. This study compared Korea’s certification system of Green Standard for Energy and Environmental Design (G-SEED) to LOTUS, a Vietnamese certification system and checked the operating methods. Especially the certification criteria of non-residential buildings were comparatively analyzed. Certification criteria in G-SEED and LOTUS certification systems have similar categories and weights. Regarding certification items, there are similar items in terms of assessment methods. However, some items are assessed separately by each system. The results of this study would be available as fundamental data for developing an international certification system for G-SEED. This study could be available as a reference in the development of global certification system in the future.

With the bottlenecks of traditional manufacturing technology becoming increasingly prominent, manufacturing industry need to adjust and upgrade the industrial structure, and intelligent manufacturing is the future development direction of manufacturing industry. According to the characteristics of complex, open system hierarchy structure and distributed multi agent of intelligent manufacturing, in order to solve the problem of information integration and collaborative processing of the organic elements of intelligent manufacturing collaborative perception process, it is necessary to give the autonomy of intelligent manufacturing entities to make it to form a fully functional agent, and these agents are connected to the communication network as a network node, so as to realize the data sharing and collaborative awareness processing function between the intelligent manufacturing body. Therefore, this article build the intelligent manufacturing system based the multi Agent and Storm-Hadoop distributed cluster framework through the research and analysis of distributed artificial intelligence and distributed cluster mechanism, and provides a collaborative framework based on multi Agent and Storm-Hadoop for information integration, data sharing, collaborative processing of collaboration awareness problem for multi manufacturing subjects of intelligent manufacturing. The simulation results shows that the cooperative sensing framework proposed in this paper can provide an effective information, data and knowledge processing mechanism and method for realizing multi subject intelligent manufacturing collaborative awareness.

By the method of EVA emulsion coating, cron stalk-magnesium oxychloride cement composites (C-MOC) was modified to study the effect of EVA emulsion content on C-MOC density, the coefficient of thermal conductivity, water resistance and mechanical properties. Furthermore microstructure of C-MOC was analyzed by SEM. The results show that: with the increase of EVA emulsion content, the coefficient of thermal conductivity and softening of C-MOC increase, but water absorption reduces. When the content is 80%, the flexural strength after 28 days could reach 3.65 MPa and the compressive strength is 4.69 MPa, reaching the maximum. At the same time, C-MOC density is 816 kg/m3 and thermal conductivity is 0.111 W/(m·k). Water absorption is 36% and softening coefficient was 0.47. It is believed that EVA emulsion could form a thin film on the outer surface of the corn stalk by microscopic analysis, increasing the roughness of the straw surface and reducing the gap between the stalk. Since the EVA emulsion has good compatibility with the magnesium oxychloride cement, they could constitute a whole jointly with glue liquid, crystal and fiber, playing the role of enhancing the surface. Therefore, water resistance, thermal conductivity and mechanical properties of C-MOC have been improved effectively.

This paper presents a review of some of the applications for artificial muscle and several material of artificial muscle. We focus attention on the polymer material artificial muscle, which responds to electrical stimulation with a significant change in shape or size. Through our research on a variety of materials and the analysis of the mechanical properties of muscle movement, finally we designed the artificial muscle device the imitation of muscles stretching device. This article describes the structure and performance of the device.

Harvesting grain directly has been the development trend of modern maize combine harvester. To satisfy the demand of harvesting grain straightly type maize combine harvester for large feeding rate, low damage rate, high threshing rate, the longitudinal axial flow threshing and separating device was designed. It could also increase the separating rate of grain and miscellaneous, and reduce the burden of cleaning device. Threshing gap was adjustable in the range of 30 to 60mm, which reduced the incidence of jam faults effectively in the threshing process. Spiral blade on feeder, threshing rasp-bar and separating nail were replaceable, which improved the efficiency for threshing and separating.

Porous irons with only micropores were produced through powder metallurgy route. Corn starch of small particle size (5-15μm) was utilized to regulate the densification of green compacts. The structural and mechanical properties of porous irons sintered at different temperatures were evaluated. The porosities increased with increasing the starch content, which reduced compressive strength and increased volumetric shrinkage. The compressive yield stress increased with increasing sintering temperature. It was also found that the effect of sintering temperature on the microstructure and compressive properties was more obvious when green compacts were less densified. Moreover, volumetric shrinkage of porous irons without adding starch remains in a quite low level for different sintering temperatures.

Combined with the research of dynamic mechanical properties of concrete under earthquake action by lots of scholars home and abroad, research status of rate-dependent test within the scope of the Earthquake strain rate (10-4/s~10-1/s) on common concrete materials is reviewed, including the dynamic uniaxial compressive properties, dynamic uniaxial tensile properties, as well as multi-axis dynamic performance. The influence of the Earthquake strain rate on concrete strength, energy absorption capability and deformation capacity such as the elastic modulus, Poisson's ratio, peak strain, and ultimate strain are discussed intensively. Results show that the tensile strength, compressive strength and energy absorption capability of concrete increase with the increase of strain rate, while the results of the various parameters of the deformation ability are not consistent, the reason is that different test results caused by different test conditions. In this paper, the reference for the further study on rate-dependent of concrete in the future is provided.

Based on the fatigue damage mechanism, fatigue life, stiffness degradation, crack width change, bending, shear fatigue properties and other aspects, this paper introduces the research progress of the fatigue properties of ordinary reinforced concrete beams. And the existing reinforced concrete beam flexural, shear fatigue properties of research ideas, methods and results are summarized, providing the basis for further study on the fatigue performance of reinforced concrete beams. At present, the research results show that the fatigue damage of reinforced concrete beam is basically in accordance with the law of the three stages. In the early stage of fatigue, the tensile concrete cracks and exits, and the damage develops rapidly. In the middle of fatigue crack growth, fatigue damage is developed into a more moderate linear growth. In the late stage of fatigue, fatigue fracture occurs in the steel bar, and the bearing capacity of the beam is quickly lost.

Video delivery application over wireless network has become increasingly important in recent years. For achieving more flexible video streams transmission, the scalable extension of the H.264/AVC standard has been developed, as well as which is combined with temporal, spatial and quality scalabilities to adapt efficiently the wireless bandwidth resource. In this paper, a cross-layer optimization for robust H.264 scalable video delivery over WiMAX network is proposed. In order to obtain a better delivery performance, the proposed method is used the hierarchical B-picture approach to classify video packets into different priorities. In the cross-layer optimization, the scalable video and packet classifier are proposed at the application layer, and the packet priority and queue allocation are used at the MAC layer. Finally, it is shown by NS2 simulations that the proposed method provides more stable wireless bandwidth and also achieves a better quality of the video streaming delivery.

This paper presents kinematic analysis and power-flow analysis of an existing 8-speed bicycle drive hub by using the fundamental circuit method. First, a planetary gear mechanism, which consists of three basic planetary gear trains connected in series, and its clutching sequence table are introduced. Based on the fundamental circuits, six kinematic equations of the drive hub are derived. Then, the power-flow diagrams at related gears are illustrated based on the clutching sequence table, and the power-flow paths of the bicycle drive hub can be identified. The results of this study are beneficial to the development of multi-speed drive hubs for bicycles.

This study showcases two independent magnetic manipulation systems to remotely control the movement of Fe3O4 nanomaterial in microfluidic chips. One system utilizes a homogeneous rotating magnetic field to carry out magnetic stirring in 100 μm and 300 μm flow channels. The mixing results of this system revealed that adding Fe3O4 nanoparticles to the solution enhances the efficiency of the micromixer by twice as much that of a device without the nanomaterial. The second manipulation system utilizes oscillating magnetic field for rapid microablation of thrombus in a microchannel. A customizable magnetic platform using 3D-printed material is also constructed. This is proposed as a feasible low-cost and portable magnetic manipulation device that can implement both applications.