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A method of thermal structure analysis is developed for supersonic missile rudder. The method calculates the aerodynamic heat based on Eckert reference enthalpy method, and calculates the temperature field by finite element method. The temperature field is taken as the volume load while calculating the thermal stress gradient and time history. Considering the influence of thermal stress, the natural vibration characteristics such as the mode and vibration frequency with time are obtained. The numerical computation results show that the aerodynamic heat is distributed unevenly across the rudder, such as stagnation point, laminar flow, transition and turbulence. The solid blocks of rudder shaft, longitudinal and transverse wall plates cause local low temperature, and large temperature gradient leads to higher thermal stress. Due to the change of material properties and thermal stress, the natural vibration frequency of the rudder has a significant decrease at sometime. The software of ANSYS was used to calculate and output cloud diagrams. The software of Microsoft Office was used to make curve graphics. The developed APDL command flow is very efficient and portable, which is convenient for complex structural model, and can provide technical support for supersonic missile rudder.

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.

In this study, the numerical computation is used to investigate the transient movement of a water droplet in a microchannel. For tracking the evolution of the free interface between two immiscible fluids, we employed the finite element method with the two-phase level set technique to solve the Navier-Stokes equations coupled with the energy equation. Both the upper wall and the bottom wall of the microchannel are set to be an ambient temperature. 40mW heat source is placed at the distance of 1 mm from the initial position of a water droplet. When the heat source is turned on, a pair of asymmetric thermocapillary convection vortices is formed inside the droplet and the thermocapillary on the receding side is smaller than that on the advancing side. The temperature gradient inside the droplet increases quickly at the initial times and then decreases versus time. Therefore, the actuation velocity of the water droplet first increases significantly, and then decreases continuously. The dynamic contact angle is strongly affected by the oil flow motion and the net thermocapillary momentum inside the droplet. The advancing contact angle is always larger than the receding contact angle during actuation process.

The variable pitch twin-screw vacuum pump has more advantage than the uniform pitch twin-screw vacuum pump. Its energy efficiency and volumetric compression ratio are specifically high. Under the cyclic gas pressure and working temperature, the rotors of vacuum pump often deform and interfere that lead to noise, vibration and rotor abrasion. In this paper, a 3D model of the variable pitch rotor generating by CNC turning process is constructed to reasonably estimate the rotor load and deformation in operation. The contact force have been analyzed to show the advantages of variable pitch rotors.

In this paper, by designing a new type of mechanism, the time-varying cylinder load ofthe reciprocating compressor is simulated. The time-varying cylinder pressure load includes fourprocesses of expansion, suction, compression and exhaust, where the pressure of the expansionprocess is gradually reduced until it is equal to the suction pressure, and the pressures of the suctionand exhaust processes are almost constant. The pressure of the compression process is graduallyincreased until it is equal to the exhaust pressure value. Through the motion simulation of themechanism, four processes of time-varying cylinder pressure load can be realized. This newmechanism will provide new ideas for the time-varying load involved in the simulation of thereciprocating compressor fault test bench.

Most of types of laser distance measuring instrument cost hundreds of thousand dollars such as Atos scanner or Depth Camera that gives depth maps of space very fast. However, the handling is too complicated for non-professional users and the utilization of 3D reconstruction is very limited. This paper introduces a workflow of 3D reconstruction using a new cheaper instrument, the Microsoft Kinect. The first experiences with Microsoft Kinect v2 sensor are presented, and the ability of 3D modelling for mechanical parts is investigated. For this purpose, the point cloud on output data as well as a calibration approach are demonstrated.

In this research, a shear-mode MR damper that can replace conventional passive damper of a front-loaded washing machine is designed, manufactured and an experiment based model is employed to characterize hysteresis behavior of the damper. Firstly, an optimized MR damper for front loaded washing machine is manufactured and an experimental system is set up for testing hysteresis behaviour of the damper. The experimental test is then conducted and presented. From experiential results, hysteresis of the damper is investigated and a suitable hysteresis model is proposed for the damper. The proposed hysteresis model of damper is then evaluated through experimental results.

The method of high temperature physical vapor transport (HTPVT) is an available approach to prepare silicon carbide (SiC) ceramics with high density and high purity. In the present work, α-SiC (6H-SiC) and β-SiC (3C-SiC) powders were used as starting materials respectively to fabricate SiC ceramics with HTPVT process, and the effects of starting materials on nucleation, density, microstructure and mechanical properties of SiC ceramics were investigated. It showed that at high temperature, the decomposition rate of β-SiC was higher than that of α-SiC, and at the initial nucleation stage, the average grain size of SiC crystal obtained with β-SiC starting materials was smaller than that with α-SiC starting materials, because higher vapour pressure of gas phase which decomposed by β-SiC starting materials facilitated nucleation and growth of SiC grains. Density of the resulted SiC ceramics using α-SiC and β-SiC as starting materials was 3.16 g·cm-3 and 3.17 g·cm-3, indicating close values, while, using β-SiC as the starting materials, the grain size was smaller, consequently, the flexure strength was higher. Increasing growth temperature from 2200°C to 2300°C, the densities and the flexure strength of the SiC ceramics using either α-SiC or β-SiC were decreased.

A new heat treatment procedure is proposed to remove the strong texture microstructure of JIS type G4051 S45C rolled steel, thus making ease for further machining process and hardening to obtain higher hardness and grain homogeneousness over the common heat treatment procedure. This procedure includes annealing and normalising process and is applied for f14x20 mm samples. By annealing process at approximate 840 to 880°C for 2 to 6 hours, the strong texture has been improved by about 30-40% in comparison to the conventional crystallization process. By normalising process at 880°C and 920°C for 15 minutes, the strong texture has almost treated. The grain size along the rolling direction (RD) and traverse direction (TD) are in the range of 15 to 50 μm.

Electrical discharge machining (EDM) process is widely used to process hard materials in the industry. The process of electrical discharge is changed and called PMEDM when alloy powder is added in the oil dielectric. In the current study, the effect of tungsten carbide alloy powder added in the dielectric on the surface roughness (Ra) and the micro hardness of surface (HV) status of the workpiece SKD61 after machining is investigated. Studies show that the surface roughness and the micro hardness of surface obtained by PMEDM is generally better than that by normal EDM. The method can be applied for improving surface quality such as improving strengthening of molds and machine parts.

This paper presents experimental studied results about surface roughness during end milling SKD11 steel under room temperature and work-piece preheated condition. Conventional samples were first performed. The samples which are same technical parameters were then performed at elevated temperatures to evaluate effective of heating process on the surface roughness. Orthogonal array Taguchi method was used to experimental design. The results showed that the surface quality of product was significantly improved under thermal - assisted milling. The surface roughness model during machining at room and elevated temperatures were evaluated and showed a good agreement with result of experiments.

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.

Surface modification of activated carbon (AC) could be done through different methods in order to modify their specific physical and chemical properties to facilitate metals removal from wastewater. Three methods were used to modify the rice husk AC (RHAC) including the use of (1) HNO3, (2) dithizone and (3) the combination of HNO3 with dithizone. These modification agents were increased its affinity towards the desired pollutant. The modification methods demonstrated the effective process for the metal ions adsorption capability and the removal of them from water. For Ni2+ and Cd2+ adsorption, RHAC was modified by HNO3 giving the best adsorption capacity in comparison with using dithizone or the combination of HNO3 with dithizone. That adsorption was reached 17.23 mg/g for Ni2+ and 29.61 mg/g for Cd2+. Additionally, the surface area, which was characterized by BET (Brunauer–Emmett–Teller) of RHAC, was 710.8 m2/g and DA micropore volume was 0.447 (cm3/g). Especially, the only modified RHACs had the peak of N-H functional group by using Fourier transform infrared spectrum (FTIR). Besides, the only RHAC modification by HNO3 had peak of C=O. That significantly contributed to increase the metal ions adsorption capacity of RHAC.

We report the new strategy by investigating the novel Ti0.7Mo0.3O2material can just as easily be used as a conductive support for PtRu for DMFCs to prevent not only the carbon corrosion but also improved activity of catalyst due to some functional advantages of novel Ti0.7Mo0.3O2support. The Ti0.7Mo0.3O2nanoparticle have good crystallinity with well-defined fringes corresponding to the 3.45 Å spacing value of the {101} plane of anatase TiO2, which were good according to the XRD pattern. The BET surface area measurements showed that the Ti0.7Mo0.3O2possessed 125 m2g-1Fig. 3 shows the TEM measurement of Ti0.7Mo0.3O2nanoparticle and Pt/Ti0.7Mo0.3O2, it can be observed that spherical PtRu alloy particles with an average particle size of 2-4 nm were uniformly anchored on the surface of Ti0.7Mo0.3O2support. More importantly, we found that there has a strong metal support interaction (SMSI) between the PtRu noble metal and the Ti0.7Mo0.3O2support material - resulting in facile electron donation from the Ti0.7Mo0.3O2support to PtRu metal with an ultimate drastic decrease in the d-band vacancy of Pt. Thus, the unique structural features of the Ti0.7Mo0.3O2support and the PtRu/Ti0.7Mo0.3O2catalyst appear to provide a suitable combination favoring that promise for the high performance of methanol oxidation, CO-tolerance in DMFCs.

The materials currently used in proton-exchange membrane fuel cells (PEMFCs) require complex control of operating conditions to make them sufficiently durable to permit commercial deployment. One of the major materials challenges to allow simplification of fuel cell operating strategies is the discovery of catalyst supports that are much more stable to oxidative decomposition than currently used carbon blacks. Here, we report the synthesis and characterization of advanced nanostructure Ti0.7W0.3O2prepared via a low-temperature solvothermal process without using any surfactants or stabilizers. A promising doped metal oxide is a candidate for such a durable catalyst support. The synthesized nanoparticles were characterized by XRD, TEM measurements. Results show that Ti0.7W0.3O2exists in a single-phase solid solution with anatase phase of TiO2. Interestingly, the average particles size approximately 5 nm that could be promised to have a large specific surface area, which is an extremely important factor for promising catalyst support. Moreover, Ti0.7W0.3O2synthesized at 200 °C for 6 hours obtains the smaller particles size without particles agglomeration compared to previous researches. These results open a new approach for synthesis nanostructure Ti0.7W0.3O2by a solvothermal process for further application as catalyst support in PEMFCs.

We report the facial synthesis of BiVO4crystals with different morphologies by the solvothermal and hydrothermal process. The phase structure and morphology as-synthesized samples were characterized by XRD, FE-SEM, and UV-vis DRS spectroscopy. We also investigated the photocatalytic activity of BiVO4for the decomposition of rhodamine B (RhB) under visible light irradiation. The results showed that oliver-like BiVO4was obtained when using the mixed solvent of ethylene glycol and water while starflower-like BiVO4was obtained using the mixed solvent of ethylene glycol monomethyl ether and water. The hydrothermal evolution process the BiVO4product with a rod-like morphology. Oliver-like BiVO4with pure monoclinic scheelite phase and high specific surface area exhibits efficient photodegradation of RhB (k = 7.82x10-3min-1).

We investigated the use of durian shell-derived activated carbon (DSAC) for the removal of Cu2+. To determine the optimal condition for Cu2+ removal, the response surface methodology (RSM) was used to establish a second-order polynomial model with variables such as Cu2+ concentration (Ci), adsorbent dosage (dDSAC) and pH. With R2 = 0.9847 and P-value < 0.0001, the model was proved to be statistically significant. The RSM based confirmation test revealed that the removal of Cu2+ was maximum (99.6%) at optimal conditions: Ci = 61.6 mg/L, dDSAC = 5.0 g/L and pH = 5.2. Based on calculated R2, data fitness for adsorption isotherms were positioned as follows: Langmuir > Tempkin > Freundlich. In other words, monolayer adsorption was the most favorable behavior with maximum capacity of 76.92 mg/g from Langmuir model. Interestingly, DSAC was reused at least five times without a considerable decrease of Cu2+ removal efficiency. Therefore, durian shell can be used as a highly effective, reusable and promising raw material to fabricate the activated carbon.

A design and simulation for L-shaped slot microstrip line antenna with semicircle defected ground structure has been researched, the main purpose is suppressing the existence of higher order harmonic. In this paper, simulated soft (Ansoft HFSS V.6.0) used to be simulated the frequency response under different parameters such as dimensions, amounts of SDGS. The results show good performance of SDGS in higher resonant frequency suppression. Final, an antenna with 2.4GHz center frequency had been design and fabricated.

A design and simulation for low pass microstrip line filter with defected ground structure has been researched, the main purpose is with the simplest method to design an ideal low pass filter. In this paper, simulated soft (Ansoft HFSS V.6.0) used to be simulated the frequency response under different geometric shape of DGS. The results show good performance of a low pass filter with DGS. Final, a low pass filter with DGS design and fabricated, The properties are shown as flow: center-frequency: 7.28G, S21:-47dB, cut-off frequency: 5.88GHz.

A new type of recycled aggregate concrete curb is designed based on the strength comparison between the recycled concrete mixed with crushed brick masonry at an appropriate ratio with the ordinary concrete through a compression strength test. The result shows the compressive strength of this recycled concrete curb is not as good as that of ordinary concrete curb, so reinforcement measures have to be taken. The construction technique of the new designed recycled concrete curb is simple, environment-friendly and permeability, it is recommended for urban and rural roads subject to rainy weather.

Deceptive promotions occur frequently on Taobao Mall, Jd Mall and other net-shopping platforms, which not only affecting the focus online store, but also having favorable or adverse impact on other competing online stores, and cause spillover effect. From the perspective of mass and frequency, this paper used the scenario experiment method to explore the effect of deceptive promotion’s characteristics on negative spillover effect to other competing online stores. The study found that the higher the mass of deceptive promotion is, the stronger negative spillover effect of deceptive promotion from the focus online store to competing online stores is, and the higher the frequency of deceptive promotion is, the stronger negative spillover effect of deceptive promotion from the focus online store to competing online stores is. Frequency moderates the effect of mass on negative spillover effect to competing online stores; under the condition of low-frequency, there are not significant differences between high-mass group and low-mass group; under the condition of high-frequency, spillover effect of high-mass group was significantly stronger than that of low-mass group. In practice, this paper explains the effect of the characteristics of deceptive promotions on spillover effect, which provides valuable reference for competing online stores to predict spillover effect of deceptive promotion effectively.

Because the output signals of photon detectors are scattered under weak light, the single photon counting method uses pulse discrimination technique and digital counting technique to identify and count weak signals. Compared with analog recording technique, the single photon counting technique has the advantages of high signal-to-noise ratio and good anti drift performance. Discrimination voltage is an important part of single photon counting, which will greatly affect the signal to noise ratio (SNR). The selected process of discrimination voltage is very complicated, especially the number of photomultiplier tube spectral analysis system [1], discrimination voltage selection process more time-consuming. This paper presents a software for automatically searching voltage discrimination. The software can automatically measure the discrimination voltage of a plurality of photomultiplier tubes, greatly improve the efficiency and accuracy of screening voltage selection, and verify the effectiveness of the screening voltage software by calculating the signal-to-noise ratio.

Aiming at the problem of the complicated process, the low precision and efficiency of crack detection and key geometric feature of the circular saw blade, the quality detection system of the circular saw blade based on the nondestructive testing and laser measurement technology is studied. By using the laser measurement technology and optimizing the data processing method, the face runout, the thickness of the circular saw blade are measured. The crack defects in the tooth root region of the circular saw blade are detected by eddy current nondestructive testing technology. The system achieves the radial detection of 1mm radial sawing, the detection accuracy of the round beating is> 0.03mm, and the thickness measurement accuracy is> 0.005mm.

According to level I and level II stability analysis of the API617 (7th edition), the stability of a natural gas pipeline compressor system is studied. It is found that the rotor bearing system is unstable. Therefore, adding swirl brake on the system is to improve the damping characteristics. The stability of the unit can meet the requirement of API617 dynamic design. The research demonstrates that the stability of compressor system is not solely determined by the rotor system, but the stator system is also an important factor. In particular, the swirl brake on the diaphragm can reduce the cross coupling stiffness generated by the seal, and it is significant to improve the stability of the compressor system.

A multi-section high efficient pumping unit was designed. The pumping unit has a multi-stage structure including forcer part of the use of linear motor and four-stage linear motor extract oil one after another. Consumption can be reduced and the operating efficiency of the machine can be improved. Each component of high efficiency linear pumping unit is introduced. Using power inverter to control pumping unit without complicated equipment and contact limit controller, pumping stroke adjustment can be realized. The control system adopts the vector control, high control precision and anti-interference ability.

Shipping damage is one of the key problems of photovoltaic (PV) failures in the field. In addition, the detailed documents and industry standards are necessary, to avoid cell breakages or cracks during transportation. Therefore, ITRI coordinated some TFs to set up a series of experiments on the performance evaluation for PV-cell and PV-module caused by transportation and shipping. This work aims to standardize the test method for performance criteria of PV-cell and PV-module for transportation, and evaluates a guideline and risk analysis for shipped package of PV product to meet the relevant reliability concerns in a long-term perspective. PV products are shipped not only in a fab by forklift trucks or handling, but also transported outside a fab by shipping vehicles such as truck, train, aircraft and shipboard. Consequently, results were applied to SEMI Doc. 5431 and released as SEMI PV56 [1] by voting in 2014. PV product’s makers and buyers, or any other party interested like package designers, can thus have a common testing standard to refer to when desired.

This work aims to analysis the SEMI PV standards developed in Taiwan during 2009 to 2014. The major technical committee (TC) and task force (TF) include Photovoltaic Technical Committee (2009), Photovoltaic Module Vibration TF (2010), Photovoltaic Cell Vibration TF (2011), Package Performance TF (2012), OPV and DSSC TF (2013), BIPV TF (2013) and Reliability TF (2014). ITRI coordinated these TFs to set up a series of experiments and discussions, which focused on the performance evaluation for PV cell, module and materials. The TFs have developed four standards include SEMI PV23 (2011), SEMI PV38 (2012), SEMI PV56 (2014) and SEMI PV57 (2014). Through these standardizations, some specific test methods and test flows were completed to evaluate the reliability for both c-Si and organic/inorganic PV products, which are helpful to improve the performances of cell and module, and propose the common testing guidelines for PV industry to refer to when desired.

With increasing applications in consumer electronics such as smart phones, laptops and tablet PCs, the need for pervasive computing with a requirement of lower power consumption is increasing every day. This opens the door for energy harvesting that could charge the batteries in these devices to keep them continually functioning in some useful state. There has been a lot of attention on flexible thin film solar cells, such as dye sensitized (DSC), organic and inorganic, given their low-cost and improving efficiency. Performance characterization DSC has been investigated, in order to clarify how to determine their performance accurately. Accurate characterization of DSC requires level lighting consideration on each very slow temporal response in the I-V curves of the DSC are clearly dependent on the voltage sweep direction, even when the sweep time is the order of seconds. Furthermore, the temporal response is dependent on different level lighting consideration. This analysis showed to improve accuracy, measurement should be real time removing capacitance effect with a Real-Time One-Sweep Method (RTOSM). Additionally, RTOSM will be useful to measuring cell performance more accurately and rapidly when evaluating solar cell performance.

The major differences between dye sensitized solar cell (DSSC) and p-n junction solar cells are spectrum absorption range, photoelectric conversion response time and standard test condition (STC). The operation principle of DSSC is using layers of organic molecules subject to lighting after excitation electronic then pass to the inorganic/organic layer of the wide energy gap nanolayer and voltage. Therefore, characterizations of DSSC are important in order to clarify how to determine its performance accurately. Such measurement requires considering the different level lighting on each very slow temporal response (hysteresis and transient) in its current-voltage (I-V) curves, which are dependent on the voltage sweep direction, even when the sweep time is the order of seconds. This paper presents a new test method for determining I-V performance of DSSC, which differs with IEC 60904-1 addressed on single and multi-junction samples. Results were applied to SEMI Doc. 5597 and released as SEMI PV57 by voting in 2014. Consequently, emerging photovoltaic device makers and buyers, or any other party interested, can thus have a common testing standard to refer to when desired.

In order to solve the spindle vibration problem which is mainly caused by the mass unbalance, the single-plane influence coefficient balancing technique was applied into the experimental study. The unbalance elimination could be done through correction weight through before adding trial weight. The coefficient magnitude, the balance weight magnitude and other parameters could be available by extracting vibration signals and measuring vibration phases. The dynamic balance effect comparison has been done under different working rotations. Results indicate that the spindle mechanical vibration decreased by 87.04%, the balancing precision also improved a lot. Such achievements would surly hold an important meaning in reducing noise, improving the equipment service life and ensuring the safely working machine.The method provides regulation strategies for the online dynamic balancing control technique. Key words:single-plane influence coefficient balancing technique; regulation strategy; mechanical vibration

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.

Bentonite has been purified by suspension method and sodiumed with sodium carbonate, and then modified with polyaniline. Finally, characterized by the polarizing microscope, the X-ray diffractometer(XRD) and Fourier infrared spectrometer (FT-IR), in order to determine the optimal preparation technology of polyaniline/bentonite. And the optimal preparation of PAn/MMT is used to research the adsorption dynamics analysis on phenol. The result shows that the sodium ion enters into the bentonite interlayer through ion exchange; When the dosage of bentonite is 5 g, the dosage of FeCl3·6H2O is 2.7 g, the dosage of aniline is 46.5 g, and the dosage of DBSA is 3.26 g, its layer spacing of modified bentonite is 2.823nm, increaseing 1.600nm than the first, so the hydrophobicity and separation effects of the modified bentonite get greatly improvement. And the dosage of PAn/MMT is 0.1 g and the initial concentration of phenol、P-nitrophenol、o-cresol is 10 mg/L, their adsorption rates reach to 51.50%, 80.56%, 62.93%, more high than the sodium bentonite under the same conditinns. It indicates that the modified bentonite is more suitable for the adsorption of benzene homologs.

The thickness of the plastic film is an important physical index to the production of plastic. The measurement reslut relates directly to the companies’ economic benefit. This paper mainly introduces the digital signal processing in the detection system of film thickness. Through a perfect processing, the system can improve its SNR and finally get a high precision. Firstly, the principle and scheme was presented. After that, this paper mainly introduces the hardware implementation of the system. It includes analog filter circuit, AD sampling and digital filter. With the experimental verification, the system realizes the measurement of the film thickness on-line which can get the precision of micrometer. At present, the equipment has aready put into use by some companies.