Abstract:The oxygen-enriched intake air technology was applied in a DI diesel engine, the volume fraction of oxygen as follows: 21%, 22%, 23% and 24% respectively. The effect of matching between pure diesel, 10%, 20% and 30% water emulsion diesel on combustion or emission was investigated and simulated. The experiment and simulation were both carried out under the maximum torque working condition of the test engine. The result revealed that under the conditions of burning same emulsion diesel, with the increase of oxygen concentration, the ignition timing decreased and the max pressure increased. Under the same intake air condition, the ignition timing will be delayed with the increase of water rate in emulsion diesel. The ignition timing and combustion rate could be controlled through different water-emulsion rates matched with different oxygen concentrations in intake air. Using 30% water emulsion diesel, the lower combustion temperature made the NO emission lower than original engine’s NO emission, even though the oxygen reached 24% in intake air. Burning 20% water emulsion diesel, when oxygen concentration is below 22%, the NO emission is better than original. The 10% water emulsion only combustion in air, which NO emission is better than original. With increasing of oxygen concentration in intake air and water rate in emulsion diesel, the smoke emission is lower than original engine. Analysis on combustion temperature with the chamber impress-cuts of TDC, ATDC 4°CA and ATDC 10°CA, the water content in emulsion diesel has great impact on low-temperature chemical reaction and the oxygen concentration in intake air is more effective on high-temperature reaction. 

Abstract:In order to confirm cylinder deactivation schemes with preferable dynamic performances of internal combustion engine motion mechanisms, the flexible dynamic model of a V8 diesel engine was established, which coupled mechanisms such as cranktrain, timing-gears, and valvetrain. The dynamic models were validated by experimental data. Motion mechanisms dynamic simulations were conducted for single cylinder deactivation. The results revealed that angular displacement amplitude of crankshaft obviously increased when single cylinder activated, which mainly consisted of low orders rolling vibration, while the change to camshaft was negligible. Motion characteristics of valvetrain were deteriorated and mechanical load increased. Deactivated cylinders which were neighboring to the single or double crunodes positions of crankshaft, behaved better dynamic performances under high speed and low engine loads. 

Abstract:The simulation model electronic unit pump (EUP) was established in AMESim environment. The accuracy of the model was validated by comparing with the experiment results. By simulating, the influence of cam profile velocity, plunger diameter, length of high pressure fuel pipe, inner diameter of high pressure fuel pipe on injection pressure, cycle fuel injection quantity, fuel injection duration and coefficient of fuel feeding was revealed. By using the design of experiments (DOE) method, and taking the interaction into consideration, correlation between various factors and injection characteristic was analyzed. The correlation coefficient was obtained by analysis, the results show that not only the single factor but also the interaction factor of various influence parameters has correlation with the injection characteristic, and the correlation coefficient represents complex law with the speed variation.

Abstract:According to the control system composition and working principle of AVNT, mathematical model of AVNT valve with cam position feedback signal was established, stability performance and characteristic of current-angle were analyzed. Simulation results show that gain margin and phase margin can make control system with guaranteed stability and better dynamic characteristics. Feasibility of the simulation model was verified by the experiments of crankshaft angel changing with input current after AVNT valve was installed in turbocharger.

Abstract:Particulate emissions of engine fuelled different proportions of biodiesel-diesel blends were collected under different fuel supplying advanced angles and different operating conditions. The change of volatile organic fractions in particulate emissions was analyzed using thermo-gravimetric analytical instrument when temperature increased. The results showed that under the tested conditions, compared to the proportions of biodiesel-diesel blends, the change of fuel supplying advanced angle had little influence on the amount of volatile organic fraction in the particulate emissions. The volatile organic fraction in the particulate emissions increased with the increase of the proportions of biodiesel in the blends; volatile organic fractions peaked at the evaporation temperature of 150~180℃, and with the percentage of biodiesel increased, the volatile organic fractions were more concentrated in the temperature range with the increase of percentage of biodiesel.

Abstract:In order to investigate the influence factors of DeNOx behavior in SCR(selective catalytic reduction) catalysts, with the aid of CFD (computational fluid dynamic) coupled with chemical reaction dynamics, a full-processing simulation and validation tests were conducted on the catalytic substrate. The results show that the temperature is the major factor to influence the conversion efficiency. The optimal temperature for SCR reaction is from 350 to 450℃. Space velocity has a certain influence on conversion efficiency of SCR at low temperature. Increasing NO2 concentration can improve the conversion efficiency, but the volume concentration of NO2/NOx need to be controlled within 50%.

Abstract:A zero fuel auto-learning calibration strategy was adopted and the concept of engine segment acceleration was introduced. When the necessary condition for calibration and the rail pressure defined by the calibration were required in overrun phase, zero fuel calibration triggered small injections to a cylinder, and attempted to detect a change in the engine crankshaft segment acceleration. Then, the parameters for the injections were changed in predefine step value for the energizing time until a predefined segment acceleration change was detected between two neighborhood injections. Finally, the energizing time was saved as zero quantity calibration value of the injector in the rail pressure defined. The injection bench and the experimental vehicle test results showed that zero fuel auto-learning calibration strategy does not need to add any components, and it has higher calibration veracity and real-time characteristic.

Abstract:First of all, the control commons of idle speed adjust (ISA), power take off (PTO) and cruise control system (CCS) were concluded; and then, ISA, PTO and CCS were designed based on the software and hardware reusability and were successfully realized on GD electronic controlled diesel engine; last but not the least, the control strategies were verified on the hard in loop (HIL) bench and further on vehicle test, whose result demonstrated that the control functions based on software and hardware reusability would not affect with each other and have a satisfactory control result. By using this method, not only the duplication effort can be avoided, but the development cost can also be cut.

Abstract:Based on the effect of infiltration head on soil water movement, the assumption of layered calculation was put forward. The model of soil water movement at different infiltration heads was established, and the finite difference method was used to solve it. A series of soil column infiltration experiments at different infiltration heads were conducted to verify the model. The computational soil water contents derived from the model was in accordance with the experimental results, the maximum relative error was 4.8%.It indicates that the mathematic model of soil water movement at different infiltration heads is correct and solving of the model with the finite difference method is feasible.

Abstract:In order to discuss spatial distribution characteristics of soil hydraulic properties of Lou soil, samples were taken along lines in the area of wheat and maize crop rotation in Dazhai village, Yangling, Shaanxi. Soil water characteristic curves, saturated hydraulic conductivity, soil water content and soil bulk density were measured. Brooks—Corey models were used to describe soil water characteristic curves, and the spatial variation of Brooks—Corey model parameters (θs, α and n ), saturated hydraulic conductivity (Ks), soil water content (θ) and soil bulk density (ρ) were analyzed with multifractal method. Results indicated that Ks,α and n had stronger variability,θs, θandρshowed weak variability in the entire sampling directions; the soil hydraulic properties showed multifractal features at different sampling directions; the multifractal structures ofθs, θ and ρwere weak at different sampling directions which indicated weak spatial variability.Ks,α and n had obvious multifractal structures at different sampling directions. Their generalized dimensions ranged from 0.7 to 1.9, from 0.6 to 1.2 and from 0.9 to 1.1, respectively, spatial variability were strong, and the spatial distribution structure of Kswas more complex than αand n. 

Abstract:The special distribution of root and root growing dynamic in the grape growth period were studied with a core sampling scheme and ET—100 system. The results showed that roots of grape vine centralized in the radial space between 0 and 100cm, and the amount of the roots accounted for over 80% of total roots. The horizontal distribution of root density of grape vine was minus exponent. The roots of grape vine centralized in the depth between 0 and 60cm, and the amount of the roots accounted for over 75% of total roots. Under the alternate partial root zone irrigation, the available root of grape vine grew differently in the wetted zone and in the dry zone. It was limited by soil moisture condition and its own growing. The distribution of new root of grape vine was parabola in both the wetted zone and the dry zone.

Abstract:The influence of offsets (-0.25mm, 0, 0.25mm, 0.50mm) of dental labyrinth channels of drip emitters on hydraulic and anti-clogging performance was studied by the following methods: there were numerical simulations carried out for the liquid-phase flow and the liquid-solid two-phase flows in the flow field by the CFD program Fluent, and the samples were tested. The obtained results showed positive relationship between offset and discharge coefficient, and negative relationship between offset and flow state exponent. With the increasing of the offset of emitters, the anti-clogging ability declined. Thus, combining the hydraulic and anti-clogging performance, under the condition of adequate flow state exponent, it put forward a suggestion that reducing the offset as much as possible to enhance the anti-clogging performance.

Abstract:Because the current methods for determining specific yield of undisturbed soil are not precise, aimed at designing a new determinator and proposing a new test idea and its calculation method, the research was conducted. First, the structure of a new determinator and its operational process for specific yield were proposed. Second, based on the analysis of infiltration and water release process of soil and the definition of specific yield, the formula presented by physical property parameters of medium and penetration liquid was obtained for computation of specific yield. The analysis results and examples indicated that the determination process of the determinator designed is simple. The seepage process was approximately the same as the practical flow pattern, and the formula has high accuracy.

Abstract:In order to prevent and eliminate vortex and the vortex tube occurred in the suction passage of two-way-reversible pumping system for the safe operation of the pump unit, an additional curved guide pier was placed on the bottom of suction passage under pump mouth. By using the CFD software the numeric simulation was made to obtain three-dimensional flow fields inside the pumping system with the additional guide pier and predict the performance of the pumping system. Combined with the model test, this paper focused on the velocity distribution of suction passage outlet, and its influences on the pump system performance. Both the computation and the measurement results showed that the additional guide pier on the bottom inside the suction passage did not effect on the velocity distribution of suction passage. The velocity evenness of suction passage outlet reach 93% with guide pier, which can meet the needs of pump operation. The performance of the pumping system was good and the high efficiency of the system at BEP is 68.89%. Experimental observations showed that the set of the guide pier could effectively prevent the vortex generation under pump inlet, the vortices were not found within the suction passage under different operation conditions. The pump ran smoothly without vibration. Comparing the calculated results with the model test results of the outlet velocity distribution of the suction passage, both of them are similar in overall structure and pump performance prediction at BEP is consistent with the test results. 

Abstract:The large eddy simulation method with sliding mesh technology was used to investigate unsteady flow characteristic in a double-suction centrifugal pump on different operating conditions. The unsteady flow in the impeller, especially on the blade surface was focused on. The results showed that the rotating frequency dominated the pressure fluctuations in the impeller at design and off-design conditions. The amplitude of the pressure fluctuation became higher when the flow rate was farer from the design flow rate, especially at Q/Qd=0.62 that the maximum amplitude occurred, nearly three times of design condition. At design condition, the maximum amplitude of pressure fluctuations happened on the blade leading edge, nearly 14% of average pressure, which was respectively 86% and 169% higher than the centers of the blade pressure side and suction side.

Abstract:Double-volute casings were introduced to reduce the radial force that is inherent in single-volute designs. A general three-dimensional computational fluid dynamics（CFD）simulation of a double-volute centrifugal pump was presented to predict hydraulic performance and impeller radial force. By using the shear stress transport (SST) k—ω turbulent model, the simulation results in the form of characteristic curves were compared with the experimental data. The result presented that the head and efficiency of the original double-volute pump drop were 21.8% and 41.3% respectively at design point due to the failed dividing rib (splitter) in the volute casing. Thus, with the aim to analyze the effects of rib structure on pumps, three optimized rib schemes were designed to reduce the impeller radial force and keep the hydraulic performance. Three factors were considered in the rib design: start point, end point and curve equation. According to the steady numerical simulation result in each optimized scheme by CFD, No.2 scheme reduced about half of the radial force while keeping the hydraulic performance. A method in designing the rib structure for double-volute centrifugal pumps was provided.

Abstract:Based on the RNG k—εturbulence model and Rayleigh—Plesset cavitation function, three dimensional turbulent flow fields in centrifugal pump with inducer were calculated and analyzed numerically. The results showed a good prediction of the head drop for five flow rates. The hydrodynamic mechanism of the head drop was investigated through a local and global study of the flow fields. It was found that head began to approximately drop when the cavitation sheet reached the throat between two adjacent blades. The total pressure breakdown caused by cavitation firstly occurred in the upstream region of the impellers, then progressive decreased as the pressure rose in the whole blade-to-blade passage. Meanwhile, the cavity increased the total pressure of local regions, which would move downstream by the development of cavitation.

Abstract:In order to reveal the internal flow laws of large-scale mixed-flow pumps, a high specific speed mixed-flow pump was simulated based on the standard k—εturbulence model and SIMPLEC algorithm by using software FLUENT. The axial velocity and circulation distributions of steady flow under working conditions of 0.8Qopt, 1.0Qopt, and 1.2Qopt at impeller outlet were obtained. The numerical results showed that the flow was stable under all the three working conditions; the axial velocity gradually decreased from hub to tip; the circulation flow pattern of the mixed-flow was nonlinear at impeller inlet, and approximately uniform at impeller outlet. The negative pressure zone which gradually expanded with the flow rate increasing existed obviously at the suction side. The study provided a certain reference for the hydraulic design of mixed-flow pump.

Abstract:According to the fact that water distribution of variable rate complete fluidic sprinkler is not uniformity under different pressures, 20PXH variable rates complete sprinkler was taken as the research model, and eight different schemes of vice nozzles were designed and analyzed by jet water theory. The water distribution was measured. The method of analyzing the test data by different sprinkler irrigation intensities under different pressures was applied, and the best scheme was obtained. The test for water distribution under different pressures and baffle angles was carried out. Taking maximal uniformity coefficient as the function objective, and the range of baffle angle and uniformity coefficient as the constraint conditions, the comprehensive evaluation function of variable rates of the complete sprinkler uniformity was created for the first time. The optimum baffle angle is 21.2° by derivative the function.

Abstract:The three-dimensional internal flow field of cross flow fans with 30°twisted blade was simulated with computational fluid dynamic (CFD) method. The influence of each structure parameters (volute case gap, volute throat gap, internal circumferential angle of the blade, external circumferential angle of the blade, blade numbers, the ratio of internal diameter to external diameter of the impeller or twisted angle of the blade) on the volume flow rate of the cross flow fan outlet was numerically researched. The optimal combination of seven structural parameters with the optimal performance of the cross flow fans was obtained by the orthogonal design method. Under the constant impeller external diameter and rotating speed, the optimal combination of structural parameters are as follows: volute case gap εc is 1mm, the volute throat gap εt is 2mm, the internal circumferential angle of the blade α is 90°, the external circumferential angle of the blade β is 20°, the blade numbers n is 30, the ratio of internal diameter to external diameter of the impeller γis 0.75, and the twisted angle of the blade θis 90°. It is obtained that the volume flow rate of the outlet of the optimized cross flow fan was increased by 25.2%. By means of the detection device of cross flow fan’s performance parameters, the air outlet average velocities of the optimized and original cross flow fans were experimentally tested under the constant impeller external diameter and different impeller rotating speeds. The experimental result showed the air outlet average velocities of the optimized cross flow fan were increased by 4.6%. The theoretical calculation results were consistent with the experimental test results. 

Abstract:In order to investigate the resistance characteristics of flap gate, the experimental and numerical simulation studies of resistance loss of flap gate were performed. Outlet circulation of the pump has great influence on resistance loss of flap gate, so the resistance loss and the square value of flow do not show the proportional relationship. In the conditions of the same flow, efficiency decreased value of pump system was negative correlated with the open angle of flap gate. On the basis of numerical simulation, flow patterns of the outlet were analyzed with and without flap gate under designed operating condition. The resistance loss of flap gate was predicted. A good agreement was achieved between the predicted data and the experimental data under designed operating condition.

Abstract:Operating conditions of the floating impeller was simulated with special equipment, and the fore-and-aft pressure of the back seal ring on the impeller was measured directly. The test curves of fore-and-aft pressure of the back seal ring and pump head were obtained. Thus the fluid leakage curve of the balance cavity of the floating impeller was got. The study solved the calculation problem of chamber pressure and leakage calculation in balance cavity of the floating impeller.

Abstract:Based on the technology of biomass powder heated by hot solid heat carrier (ceramic balls), an original down flow tube reactor (DFTR) for bio-oil production from biomass flash pyrolysis was developed. The structural design process of the critical parts was introduced in detail and the experiments were conducted to test the performance of each part of the DFTR, including the solid heat exchanger, the particle feeder, the down flow tube, the particle separator and the quencher. The results indicated that the temperature of the solid heat carrier fluctuated little and its feeding rate could be controlled precisely. The solid heat carrier and biomass char can be separated completely. The hollow-cone type nozzle is very suitable for quenching the pyrolyzed gaseous products which can atomize well as the nozzle diameter is 4.0mm and the fluid flow pressure is 0.2MPa. The pyrolyzed bio-oil yield recovering from agricultural residues reached to 43% as this type nozzle is used to quench the condensable vapor.

Abstract:A method for predicting product-yield of corn stalk pyrolysis was established by means of BP neural network model. The model consisted of three neuron layers: input layer with four nodes which affected the pyrolysis process. It included input power, air flow rate, feeding rate and pressure, output layer with pyrolysis liquid yield and hidden layer. If the training data were representative, the results obtained by neural network model could be well in accordance with the experimental results and its errors would be less than 5%. The results obtained by neural network are more accurate than those obtained by non-linear regression.

Abstract:The physical and chemical characterization of biomass crushed straw (practical size from 5mm to 30mm) which from major grain producing areas was studied and analyzed according to the biomass standards and methods introduced here. The results showed physical and chemical characterization of corn straw from different areas has significant difference. For northeast area, the static angle of repose was maximum, the ash was minimum and bulk density was 17.25%, lower than that of other area. The physical and chemical characterization of different straw from the same area has significant difference, too. The dynamic external friction angle of corn and cotton straw was much higher than that of other crop straw, for bulk density, the soybean, cotton and peanut straw was maximum. The model of net calorific value and proximate analysis was developed. The verification results showed that the largest regression coefficient P value was less than 0.05.

Abstract:Dynamic valid wind speed of aerodynamic characteristic wind wheel was evaluated based on BP neural network.According to the evaluated valid wind speed dynamically and combined direct wind speed control with indirectly wind control, a new complex control method was proposed. With this complex control method, dynamic characteristics of MPPT under indirect wind speed control can be obviously improved when wind speed evaluation is estimated with error. Besides, it can also follow the fluctuations of wind to increase the efficiency of wind power.

Abstract:O/W emulsions (pH value 7.0) stabilized by whey protein isolated was prepared as the primary emulsion at first, and then polysaccharides with different electrical properties, e.g. anionic pectin, neutral guar gum, and cationic chitosan were added to the secondary emulsions structure. The influences of pH value, protein and polysaccharide ratio on the formation of protein-polysaccharide multilayer membranes were investigated. It showed that no electrical reaction between guar gum and emulsion particles could be detected. Chitosan could adsorb to the surface of particles at a pH value 5.0~6.0, however, the formed WPI-chitosan secondary emulsions were unstable. Pectin molecules could absorb to the surface of particles and formed WPI-pectin secondary emulsion at the pH value 3.0~5.0. Stable WPI-pectin secondary emulsion could be formed at pectin concentration 0.2%~0.5%. 

Abstract:The soybean meal was used as the raw material to prepare soy protein isolate (SPI) with high emulsification activity (EA) by the method of microwave-assisted phosphorylation. A response model was established by the central composite rotatable design, with concentration of SPI, ratio of sodium tripolyphosphate (STP), microwave power, time of reaction as four variables and the emulsification activity (EA) as the evaluation index. Response surface analysis revealed that the optimized conditions of preparation of soybean protein isolate with high EA by microwave-assisted phosphorylation were as follows: concentration of SPI 10%, ratio of STP 16%, microwave power 480W and time of reaction 4min. The response model was valid in analyzing and predicting the extent of EA due to its higher fitting degree and less experimental error. Under the optimal conditions, the EA reached 66.8 and the emulsification stability (ES) reached 29.80min. Compared with the previously unmodified SPI, the EA and the ES were increased by 134.4% and 61.6%, respectively.

Abstract:The electrical conductivity method for determination of acid value in edible oil was developed based on the electrical conductivity change value of alkaline solution during reaction, and the effects on determination of the varying condition, as concentration of the alkaline solution, types of the oil samples, temperature and the solid-liquid ratio were explored. The method was validated by Chinese national standard methods. The results showed the experimental conditions had no significant effect on the determination. When the solid-liquid ratio was 1∶10, the calibration was y=0.0024x-0.1571 (where x is the value of the conductivity change, y is acid values), R2=0.9984. The linear correlativity of the determination of the acid value between two methods was very well, the relative deviation of blind samples experiment’s data were less than 10%.

Abstract:Extraction method of Changshanhuyou peel total flavonoids by supercritical carbon dioxide fluid was studied. On the basis of entrainer test and extraction pressure, extraction temperature, dynamic extraction time, CO2 flow rate, orthogonal experiment was carried out. The results showed that entrainer was unnecessary and the optimum extraction pressure was 35MPa, extraction temperature was 45℃, extraction time for dynamic extraction was 60min after static extraction for 40min, and the flow rate of CO2 was 3L/min. Under above process conditions, the extraction yield of Changshanhuyou peel total flavonoids reached to the maximum of 1.01mg/g.

Abstract:A part of technologies of strawberry harvesting robot was researched and an automatic picking mechanism of executive body which in connection with the strawberries planted in hill-culture was developed. Ripe strawberries could be distinguished and located by the machine vision system of the executive body, and the fruits were harvested by gripping and cutting peduncles so as to achieve scatheless picking. Moreover, a method that did not depend on high precise equipments was adopted to control the robot, so the cost was reduced greatly. Experiments of the robot were carried out and the results showed that the success ratio of scatheless picking was more than 90%.

Abstract:A recognition method of mature litchi in natural scene was researched. Through analyzing the gray and color features of litchi, the YCbCr color model was selected, and by using threshold segmentation, the Cr component image was selected to remove the complex background, then morphology operation and connected region label were used to remove random noise, and then the one-dimensional random signal histogram analysis and the fuzzy C-means clustering (FCM) segmentation were used to achieve the recognition of litchi fruit and peduncle. The recognition results under different natural conditions showed that the algorithm could segment the fruit successfully and the recognition rate reached to 95.5%.

Abstract:A C—V model based on level set and prior information was proposed and was applied to segment weed, wheat and apple images. Based on the characteristics of the image, the image was represented by a model which made the image easy to segment at first, and then the data contents of a region of interest in this model were extracted as the prior information. An initial contour by hue was obtained and the proposed model by this contour was initialized, the level set function was iteratively solved. Finally, a stationary-contour was obtained. The correct rates of weed, wheat and apple were 0.999, 0.999 and 0.846 respectively and the error rates were 0, 0 and 0.125 respectively.

Abstract:In order to acquire tea plant water requirement precisely and achieve tea plantation precision irrigation control, the distributed precision irrigation control system based on wireless sensor network for tea plantation was developed, and the system architecture, hardware configuration and software design approach were also introduced in detail. According to the characteristics of many wireless sensor network nodes highly dispersed in tea plantation, two kinds of distributed irrigation control methods applied to different scale tea plantations were proposed, and the hierarchical irrigation controller composed of fuzzy controller in the lower layer and optimal controller in the upper layer was designed. The developed system with distributed hierarchical irrigation controller can realize tea plantation precision irrigation control and satisfy the certain irrigation performance index. Preliminary experimentations indicated the rationality and practicability of the system. It can be effectively applied to the large scale precision irrigation areas, such as the cropland, the orchard and the nursery garden, etc.

Abstract:A method for an even distribution of N sampling points within a given polygon which contained inaccessible constraints was presented based on the simulation of ideal electrons’ repulsion movement. First, the edges of the polygon and the inner constraints into bunches of fixed electrons were described. N electrons can then be put into the polygon in random positions. And then they were “free and hold” one by one and were moving under Coulombic force. Finally, a balance was achieved with their resultant force and velocities approach to zero. At this time, these N electrons were evenly distributed within the given region; thus, their layout was considered to be an even sampling layout of N samples. Theoretical analysis and the experimental results indicated that electrons-repulsion simulation is a simple and efficient method for implementing even sampling layout of N samples within a complex polygon.

Abstract:Odor samples from three fattening rooms with different floor systems were collected and analyzed by using triangle odor bag method under cool and warm weather. It showed that there were significantly positive correlations between odor concentration and indoor temperature and pig weight（p<0.05）. The correlation was not significant between odor concentration and relative humidity（p>0.1）. Significant differences were found in the three pig rooms with different floor systems（p<0.05）. Odor concentration was highest in the pig room with traditional concrete floor system; full-slatted floor system was the second, and the lowest for deep-litter fermentation system. The results indicated that deep-litter system was effective for odor mitigation. Odor emission factors from the deep-litter room, fully-slatted floor room, and concrete floor room were (3.39±3.33), (3.70±1.31) and (4.33±2.39)OU/ (m2·s), respectively. 

Abstract:One kind of monitoring system with function of tracing was designed to apply in industrialized aquaculture, data communication. It was accomplished via PROFIBUS—DP. Data from field were processed by computer with algorithm of fuzzy control and artificial neural networks, and control signals were produced to ensure the system to run in style of closed loop. The technology of radio frequency identification (RFID) was also applied into the system to realize function of quality tracing. Finally the results including the precision of dissolved oxygen and temperature, the scale of total ammonia and nitrogen and the scale of pH value showed that the system completely met the demand of industrialized aquaculture and the integrity. The validity of information of tracing system also met the demands.

Abstract:The problems of the individualized product evaluation were formalized, and a product evaluation model with algorithms based on case reasoning was proposed. The case library was divided into groups through fuzzy clustering analysis, and different groups had different dynamic weights by mathematical calculation under the constraints of experience rules. The program flow chart of the algorithm of evaluation parameter weights optimization was presented. Euclidean distance with weights was adopted to search a similar instance. The final result of product evaluation was adjusted based on the similar instance. The proposed methodology demonstrated the effectiveness in an instance of the evaluation of crane products.

Abstract:An RRR—UPRR—RPUR parallel manipulator which can achieve spherical motion around fixed point was presented. The manipulator has three rotational degree-of-freedom (DOF), of which two rotational DOFs are independent and could be actuated by single actuator. The screw formulations of kinematic joints under ordinary configuration were established, which was employed to determine the three continues rotational DOF of the manipulator. Then, the kinematics of moving-platform and adjacent part were deduced, and the analytical algorithm of direct kinematics of the mechanism was established. Finally, the theoretical results are verified by the motion simulation of the prototype mechanism.

Abstract:A type of 3—PTT CNC serial-parallel manipulator with 5-DOF was designed based on comprehensive analysis of the advantages of serial and parallel which characteristics for complex surface processing. The configuration and degrees of freedom was analyzed by using decomposition and synthesis. The analysis and calculations show that the 3—PTT manipulator can satisfy the design needs of CNC serial-parallel machine and the configuration is reasonable. The working space and posture limit of manipulator was analyzed based on the singular constraints and posture factors in Matlab. Simulation results show that the analysis can reflect the complete working space of 3—PTT CNC serial-parallel machine tools and provide a theoretical basis for automatic control of working process.

Abstract:A method to identify such two important characteristic parameters of joint interfaces as fractal dimension and fractal roughness was given. The expression of normal total load in joint interface was modified. A joint interface was selected as an example in XHK5140 automatic tool-changing CNC vertical boring and milling machine tool on the basis of the experimental results about test specimen, the theoretical solutions for normal and tangential contact stiffness were verified in terms of qualitative comparison principle of resembling mode shape and quantitative comparison principle of natural frequencies. The theoretical mode shapes agreed well with the experimental results. The relative errors between the theoretical natural frequencies and the experimental ones are between -9% and 9%.

Abstract:From the perspective of differential cylinder, the differential connections of hydraulic motor were studied, and a differential connection method was put forward. Through the analysis of the differential connections of different-acting double-stator motors, the mathematical expressions of the motor’s rotational speed and torque were obtained. As for the effect of motor displacement scale factor C on the differential connection, the values of C for the single-acting, double-acting and multi-acting double-stator motor were found out respectively. These can make the motor differential connections turn out the same results or even fail to work. The number of repeated groups and failure points was calculated. This work will offer a new way for the theoretical research of hydraulic motor differential connection. 

Abstract:Based on poor Brinell hardness measurement information, a novel uncertainty evaluation method was described. According to analyzing the data of all error sources or the limited measurement results, characteristics of these data were gained. And then, by big sample random simulations, sample space of these data can be expanded. Finally, in terms of the Bessel formula and the uncertainty synthesis principle, poor information Brinell hardness measurement uncertainty can be evaluated rightfully. By a practical Brinell hardness measurement, the validity of proposed method was proved.

Abstract:In order to realize the efficient forming of difficulty forming surfaces such as vertical wall, the method of multi-stages CNC incremental forming with individuation was proposed based on the surface zoning for the triangular mesh model, and the generation method of the path which needed by each stage forming in the surface zone was studied. A triangular mesh surface zoning approach based on formability was given. Moreover a strategy to generate multi-stage spiral forming tool path for each surface area by offset was presented. The case studies indicated that the proposed method could realize surface zoning and generate smooth and successive multi-stage spiral forming path for the corresponding surface zones.