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Copyright of Coal Geology & Exploration is the property of Xian Research Institute of China Coal Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To improve the uniformity of microwave heating and enhance the quality of continuous microwave drying for raspberry pulp, a self-developed programmable logic controller (PLC) control system with pulsed microwave output was implemented. The central composite experimental design method was employed to analyze the effects of four experimental factors, namely microwave duty cycle, pulse period, air velocity and drying time on the average temperature, temperature dispersion value, moisture content, moisture content dispersion value, anthocyanin retention rate, and anthocyanin retention rate dispersion value of raspberry pulp. The optimal process for pulsed microwave drying of raspberry pulp was obtained. Compared with dried pulp quality and uniformity indexes from pulsed microwave drying, commonly used feedback temperature control microwave drying, intermittent microwave drying, and continuous microwave drying processes to develop a continuous microwave drying quality optimization control system for raspberry pulp. The results showed that the magnetron from pulsed microwave drying in the form of pulse output rectangular wave form power through the PLC control system. Turning on the magnetron intermittently was more effective than continuous microwave heating. Pulsed microwave drying of raspberry pulp has better product quality and heating efficiency, lower cost and better reliability than feedback temperature control systems. The optimal process parameters for pulsed microwave drying were microwave duty cycle of 0.6, pulse period of 17 seconds, air velocity of 1.9 m/s, and drying time of 12.5 minutes. Compared with continuous microwave drying, pulsed microwave drying resulted in the highest quality of dried pulp as a 35.31%±0.55% increase in anthocyanin retention, a 33.59%±0.23% increase under feedback temperature control, a 16.42%±0.18% increase under intermittent microwave drying. Pulsed microwave drying can control the power to reduce the dried fruit pulp temperature, improve the uniformity of post-drying quality and provide a basis for the industrial production of dried raspberry products. [ABSTRACT FROM AUTHOR]

Machine transplanting has been the primary technique of rice seedlings in cultivation in recent years. Among them, factory-scale greenhouses have been commonly used for seedling cultivation in northern China. By contrast, paddy-field seedling can be widely used to cultivate rice transplanting in southern China, according to climate, environment, and production costs. However, manual seedlings are limited to the high labor intensity and the waste of chemical fertilizers and pesticides. It is very necessary to improve the irrigation uniformity in the management of water-fertilizer-pesticide in rice paddy fields. In this study, a variable-rate spraying device was designed for water-fertilizer-pesticide irrigation in rice seedlings. A systematic analysis was performed on the large variable-rate sprinkler and the supporting equipment of fertilizer injection at a high-quality level. The overall structure and working principle were clarified for the variable-rate spraying irrigation device of waterfertilizer-pesticide for seedlings; FLUENT software was used to conduct numerical simulation on the sprinkler irrigation variable-diameter pipeline, in order to determine the optimal structural layout of variable-diameter pipeline; The flow rate of sprinkler and the inlet water of main pipe were then determined after experiments. The curved surface model was established for the pressure and electric ball valve opening; A fertilizer injection and dosing mechanism were designed using proportional integral derivative (PID) self-tuning. The real-time equal-proportion fertilizer or medicine injection was realized after optimization. The online control system of fertilizer injection and variable-rate spraying was constructed with the mitsubishi programmable logic controller (PLC) as the control core. The Box-Behnken experiment was adopted to explore the uniform performance and influencing factors of the device for spraying irrigation. The single objective optimization was applied to determine the key parameters of the device for sprinkler irrigation. The optimal combination of parameters was obtained as follows: The inlet water pressure of the main pipe was 0.20 MPa, the electric ball valve opening was 90°, and the nozzle spraying angle was 80°. Christiansen uniformity of the device was 92.69% in this case; There was a linear model between the mass concentration and electrical conductance (EC) value of the potassium chloride fertilizer solution. The variable-rate irrigation and fertilization experiments were conducted on the device. The EC values of the water-fertilizer mixture were 1.65, 1.66, and 1.68 mS/cm, respectively, in the three spraying irrigation levels. The average values of sprinkler intensity were 900.85, 1092.04, and 1263.67 mm/h, respectively. The fertilization uniformity coefficients were 85.21%, 87.86%, and 91.62%, respectively. There was a small fluctuation of EC values for the water-fertilizer mixtures under the three sprinkler irrigation levels of Ⅰ, Ⅱ, and Ⅲ. The average irrigation intensity of sprinklers varied greatly, where the coefficient of uniformity of fertilizer application was higher than 85%. The field test of rice seedlings was carried out using the variable-rate spraying device of water-fertilizer-pesticide for seedlings. The rice varieties were selected as Huahang51 conventional rice and Guang8You165 hybrid rice. The uniformity of seedling growth was higher than 95% at 13, 21, and 28 d after seeding. There were excellent quality indexes and rooting performance of the seedlings. The various quality indicators of rice seedlings fully met the requirements of machine transplanting. The experiment results showed that the variable-rate spraying device of waterfertilizer-pesticide system shared an accurate, real-time, and proportional fertilizer injection, irrigation, and pesticide spraying in rice paddy fields. The finding can provide a practical application to improve the mechanization level of rice paddy field seedlings for the high-quality of seedlings. [ABSTRACT FROM AUTHOR]

In the solid-state fermentation of soybean meal, in order to provide suitable conditions for the growth and reproduction of microorganisms to achieve good fermentation effect, the real-time temperature was monitored and controlled in the complex fermentation environment. The temperature of the fermenter was controlled by PID closed loop with PLC and the experiments with the target value of 37 °C were designed. The results show that, the peptides content and ACE inhibitory activity of fermented soybean meal reach 4.45 g/kg and 53.2% respectively at the end point, which are 5.7% and 9.92% higher than that under natural fermentation state. The temperature control system can effectively improve the quality of soybean meal fermentation products and the method is feasible. This work provides a theoretical basis for the production-oriented solid-state fermentation of soybean meal industry. [ABSTRACT FROM AUTHOR]

In response to the problems of high cost and the need for a vacuum environment in additive manufacturing equipment using laser and electron beams as heat sources, the programmable logic controllers (PLC) was used to design and independently build a powder feeding plasma arc additive manufacturing equipment. The effects of different process parameters on the macroscopic morphology, size, microstructure, and mechanical properties of single-layer and single-pass cladding layers was studied by using the single variable method. The results show that when the welding current of the welding machine is 190 A, the moving speed of the welding gun is 180 mm/min, and the powder feeding speed is 21 g/min, the smooth surface cladding layer can be obtained. At this time, the average hardness of the cladding layer is 864HV. As the welding current increases, the width of the cladding layer increases from 7.0 mm to 8.6 mm, and the height decreases from 1.9 mm to 1.7 mm. The microstructure and hardness gradually increase. As the movement speed of the welding gun increases, the width of the cladding layer decreases from 10.0 mm to 7.4 mm, and the height decreases from 2.3 mm to 1.5 mm. The microstructure gradually refines, and the hardness first increases and then decreases. As the powder feeding speed increases, the width of the cladding layer first increases to the maximum value of 11.2 mm, and then begins to decrease. The height gradually increases, and the microstructure gradually becomes fine. The hardness change pattern is consistent with the result caused by the moving speed of the welding gun. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Power Generation Technology is the property of Power Generation Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Donghua University (Natural Science Edition) is the property of Journal of Donghua University (Natural Science) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

:【Objective】Light is the most important factor affecting plant growth, development, metabolism and external phenotype. In the process of plant growth, artificial light sources are often used instead of natural light to fill the seeds and seedlings to improve the quality, yield and efficiency of fruits and vegetables. Artificial light plant is one of the important ways for standardized and efficient seedling cultivation, but its high energy consumption, accounting for 60% to 80% of the total energy consumption of plant factories, seriously hinder the promotion and application of factory seedling technology. Therefore, reducing the energy consumption of light source and improving the utilization rate of light is one of the core goals for plant seedling. 【Method】 Aiming at the problems of fixed height, high energy consumption and difficult to match the light demand of seed and seedling growth, this study developed a precise light cultivation platform for seedlings based on Programmable Logic Controller (PLC) technology by combining theoretical analysis, model construction and experiment. Taking cucumber seedlings as the object, the performance of the light intensity control system of the precision light cultivation platform for seedlings was verified, and its effect on the growth of cucumber seedlings was explored.【Result】The experimental results showed that the light intensity and light distribution uniformity were improved after the optimization of the lamp bead structure. The developed platform can fill the light of cucumber seedlings by manual, automatic, Human Machine Interface (HMI) and host computer. Through the platform optical radiation energy consumption model and the layer level adjustment control strategy, the LED operating power is effectively reduced, saving about 40.65% of electric energy. The maximum and minimum relative error of the optical platform radiation model are 34.37% and 3.57%, respectively, and the average relative error is 11.45%. Cultivation experiments showed that under the same light intensity treatment, there was no significant difference in seedling phenotype parameters and strong seedling index by comparing the precision light cultivation platform with the traditional high floor fixed platform. 【Conclusion】The precision light cultivation platform of seedlings based on PLC technology realizes automatic lifting and intelligent dimming, and saves up to 40.65% power without affecting the growth of seedlings. [ABSTRACT FROM AUTHOR]

In this paper, an experimental platform for dynamic control of offshore drilling riser suspensions in offshore drilling is developed. A six-degree-of-freedom platform is used to simulate the motion of offshore floating drilling platform. A scale model of riser is designed based on the centralized mass method and dynamic similarity principle. The suspension system of the experimental platform can realize 3 kinds of actions: up stroke control, down stroke control and non-control locking. The measurement and control system is developed by using monitor and control generated system (MCGS) configuration software, Siemens S7-1200 programmable logic controller (PLC) and proportion integral derivative (PID) control algorithm. By using this experimental platform, students can increase their perceptual knowledge of the dynamic control of riser suspension in offshore drilling. Through practical hands-on training, they can deepen their understanding of the theory, technology and device of riser suspension dynamic control, improve the teaching effect and cultivate students' innovative consciousness. [ABSTRACT FROM AUTHOR]

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electric Drive is the property of Electric Drive Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Smart Rail Transit is the property of Smart Rail Transit Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Animal lipid can be extracted from the fat of diseased carcass with the ecological and economic benefits. In this work, an extraction device combined heating and squeezing was designed to improve the yield of lipid. The analysis on statics and heat transfer was conducted to design the key components such as the pressuring, heating and separating units. Subsequently, the equipment selection was carried out, according to the material characteristics of animal skin and flesh tissue. Moreover, the key parameters for the heating, pressuring, and PLC(programmable logic controller) control system were optimized. Furthermore, the performance of the device was tested, taking suet from pig belly as experimental raw material. In addition, the viscosity of the extracted lipid was determined. The adjustable range of temperature was 25 to 300 ℃ in the device, and the pressure range was 0 to 5.0 MPa. Meanwhile, the data of heat and pressure were collected, where the control response time was less than one second. Additionally, the relative error of temperature was between 0.41% and 1.20%, and the absolute error of the pressure was about 0.2 MPa, with the requirements for lipid extraction tests. The results showed that the increasing yield of lipid extraction was found with the rise of temperature under the heating only or the combined heating and squeezing in the temperature range of 70 to 150 ℃. Specifically, the lipid extraction yields were 10.74% to 59.15% and 41.95% to 81.35%, respectively. At the same temperature, the extraction yield of lipid with combined heating and squeezing was higher than that of heating only. In particular, the lipid extraction yield of material S1(size is 10 mm×10 mm×10 mm) increased by 31.21 percentage points at 110 °C. Because the structure of the raw material was hardened under the action of heat, the release of lipid was accompanied in this process. Further, the action of pressure provides the power of lipid movement, for this reason the lipid extraction yield was significantly improved. There was no significant increase in the lipid extraction yield by heating only or the combined heating and squeezing, when the temperature was higher than 130°C. Furthermore, the lipid extraction yield was observed to increase with the decreasing size of material under the action of heating only. However, there was no outstanding size effect on the lipid extraction yield under the heating and squeezing together. Moreover, the animal meat materials were achieved in the complete separation under the combined heating and squeezing. Especially, the optimal conditions were 130℃ operating temperature, 5 min heating time, and 2.0 MPa pressure to achieve a mean lipid yield of 81.35%, while the material size was S2(size is 20 mm×20 mm×20 mm). The lipid viscosity was ranged from 0.004 to 0.091 Pa·s at the temperature range of 50 to 150 ℃. Meanwhile the viscosity curve showed a steady trend, while the viscosity value remained basically unchanged with shear rates higher than 20 s-1. Newtonian fluid characteristics were observed under different shear rates at the same temperature, fully meeting the viscosity standard of industrial lubricating oil. [ABSTRACT FROM AUTHOR]

Copyright of Light Industry Machinery is the property of Light Industry Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electric Drive is the property of Electric Drive Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Conditioning temperature is one of the key factors in the quality of feed pellets during feed processing. It is a high demand to maintain the constant conditioning temperature. Specifically, too high conditioning temperature can lead to the inactivation of heat-sensitive ingredients, such as probiotics, whereas, too low conditioning temperature can be found in the incomplete sterilization of the starch paste. In this study, a Proportion Integration Differentiation (PID)-based control system was developed to control the conditioning temperature of the feed pellets during processing. The whole unit consisted of a control system, steam piping, and a pelletizer. The control system with a Programmable Logic Controller (PLC) and a touch screen was utilized to control the start/stop of the pelletizer and the opening of the electric regulating valve. The process parameters of the pelletizer were also automatically collected, according to the given time interval. A temperature sensor was installed at the outlet of the pelletizer. The PT100 temperature sensor was used to collect the conditioning temperature of the material at the outlet of the temperature in real time. Subsequently, the collected data was fed back to the PLC. The PID closed-loop control algorithm was utilized to calculate the electric actuator again after the appropriate adjustment of the parameters. The stable control of tempering temperature was realized to change the steam flow into the temperature. A systematic analysis was made to obtain the convective heat exchange process between the mixed feed and steam at temperature. A theoretical model of heat transfer was established to obtain the specific parameters using the step response curve method. After that, the data curve was processed (R² = 0.976) to obtain a control model between the electric proportional control valve and the tempering temperature in the control system. As such, a large influence of special points was avoided on the experimental data after processing. Furthermore, the simulation analysis was carried out to determine the optimum parameters for the PID control using the Simulink platform. A comparison was performed on the response curves from three PID parameter regulations, namely the Z-N regulation, the decay curve method, and the critical proportional method. Finally, the critical proportional method was found to present the best control effect, in terms of the overshoot and regulation time in the dynamic performance indicators with the PID parameters (proportionality coefficient Kp=52.7, integral coefficient Ti=6.4, and differential coefficient Td= 1.6). The response time of the PID controller obtained by the critical proportionality method was 14 s and the overshoot was 3.3 ℃. Taking the lactating sow meal as an example, a series of prototype tests were carried out on the pelletizer. Specifically, the lactating sow meal was first crushed with the 1.5 and 2 mm sieves. The moisture content of the mixture was 10.17%, while the tempering temperature was set at 75, 80, and 85 °C. The tempering temperature was maintained within the set range after stability. Subsequently, the tempering temperature of 80 °C was chosen for the stability test. The tempering temperature was recorded every 1min during the test. The basically stable tempering temperature was achieved in the whole test process, which was controlled within (80±1) ℃, indicating the small average relative error and coefficient of variation of temperature. Therefore, the stable control of system temperature can be expected to automatically collect the pelletizing production data. Anyway, the control system can be expected to serve as the rapid response and real-time control of tempering temperature in the pelletizing process. Furthermore, the processing operation was simplified to improve automation in pelletizing production. [ABSTRACT FROM AUTHOR]

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The temperature requirements of piglets can decrease with the increasing age in the breeding farm. In this study, the growth performance and behavior of piglets were monitored in real time, in order to explore the effects of precise temperature control on the local heating, and the energy consumption of heat lamps. Forty-eight stalls of piglets were selected from two test rooms of a pig farm in Hebei Province of China. Three groups were divided: four temperature gradients group with 2 ℃ for each gradient (Group Ⅰ), four temperature gradients group with 1℃ for each gradient (Group Ⅱ), and two-stage power group (control group) with 16 stalls in each group. The age of the piglets (21 days from birth to weaning) was divided into four periods, 1 to 3, 4 to 7, 8 to 14, and 15 to 21 days. The automatic system of temperature control was used to set the different temperature gradients. The temperature control system consisted of a touch-screen, a temperature sensor, a Programmable Logic Controller (PLC), and a silicon-controlled rectifier for voltage regulation. Control group was adopted as a manual switch with two push buttons of high and low (high and low indicated the heat lamp with 250 and 175 W power, respectively). In addition, a heat lamp (250 W) was placed for the local heating of piglets in each stall. The temperature under the heat lamps, growth performance, behavior of piglets, and the energy consumption of heat lamps were measured to calculate the carbon dioxide emission of energy consumption. The results showed that the average temperatures were 24.1 and 24.3℃ in the two test rooms, respectively. The average air temperatures were 30.5, 28.1, 27.6, and 26.1 ℃, respectively, under the heat lamp with the Group Ⅰ. By contrast, the air temperatures were 29.7, 27.9, 27.2, and 26.9℃, respectively, under the heat lamp with Group Ⅱ. The air temperatures were 31.4, 27.3, 27.7, and 27.8℃, respectively, under the heat lamp with a control group. There were no significant differences in the average daily gain among the three groups (P>0.05). The survival rates of suckling piglets were 96.7%, 96.8% and 96.7%, respectively. There was no cold stress in the three groups of piglets. Compared with the control group, the energy saving rate of Group Ⅰ and Group Ⅱ were 16.7% and 26.2%, respectively. The automatic system of temperature control recovered the cost only in two and one winters, when the temperature of the heat lamps was set, according to the Group Ⅰ and Group Ⅱ. In energy conservation, four temperature gradients can be expected to better control the heat lamps, compared with the two-stage power control for the local heating of piglets. The finding can provide the reference for the optimal strategy of precise temperature control on the heat lamp, in order to improve the economic benefits of the pig farm. [ABSTRACT FROM AUTHOR]

In view of the deformation of corrugated cartons used in the packaging of steel bottles by traditional packers, a packer with carton shaping function was designed. The equipment was mainly composed of push mechanism, upper cover mechanism, upper spray mechanism, upper capping mechanism and carton shaping mechanism. The control system of the equipment was designed based on Keyence PLC and photoelectric sensor. The sealing machine could correct the shape of the paper box deformed in the process of sealing and improve the quality of packaging. At the same time, the forward pushing mechanism of the box packer used photoelectric sensors and transverse and longitudinal cylinders to push the carton, so as to avoid the accumulation of the box in a certain station in the transportation process and ensure the orderliness of the sealing process. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Dalian University of Technology / Dalian Ligong Daxue Xuebao is the property of Journal of Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Light Industry Machinery is the property of Light Industry Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Programmable logic controllers (PLC) with different manufacturers and models have their own dedicated integrated development environments, so they are not compatible with each other, and the program wring and modification ls more abstract and tedious. In response to the above phenomenon, a PLC automat programming system was designed and developed based on the Scratch platform, which was used for secondary development of the Scratch graphical programming platform. The virtual configuration design was completed by dragging and dropping component models and programming building block programs. And then human-computer interaction was performed based on Qt upper computer software. The expected functions were achieved mainly by Scratch resource file paring algorithm, PLC source code automatic generation algorithm and PLC instruction statement format verification algorithm. After verification by an example, it shows that the system can convert the visual expression scheme into executable PLC source code, which effectively improves the efficiency of PLC programming in industrial control field and can be widely used in the design and maintenance of PLC control systems. [ABSTRACT FROM AUTHOR]

Copyright of Light Industry Machinery is the property of Light Industry Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Light Industry Machinery is the property of Light Industry Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Textile Leader is the property of China Textile Information Center and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Donghua University (Natural Science Edition) is the property of Journal of Donghua University (Natural Science) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Seedling raising has been one of the most key steps in the process of rice mechanization production. In this study, a fully automatic palletizer of a rice seedling tray was designed to accurately clamp, transfer, and position the rice seedling trays in the rice factory. A Cartesian coordinate structure was selected to design the key components, according to the basic structure and working principle of the palletizer. A Programmable Logic Controller (PLC) was utilized as the control core, further to construct the hardware circuit and software program of the system. A palletizing layer detection of the rice trays was designed using the PLC. Specifically, the height of palletized trays was detected to determine the number of completed layers in the control system, thereby realizing the accurate palletizing of rice trays. The optimal ranges of the principal factors were then determined for better palletizing performance. A Box-Behnken orthogonal combination test was conducted to clarify the relationship between the main influencing factors of the operational performance (productivity, detection time of the palletizing layer detection mechanism, and the tray releasing height) and the palletizing performance indexes (palletizing passing rate and seed exposure rate). The influencing factors on the palletizing pass rate were ranked in the descending order of the detection time and tray height. Once one variable was fixed, there was a trend of first rising and then smoothing in the influence of the rest two parameters on the palletizing passing rate. Compared with the productivity, the tray height presented an outstanding influence on the seed exposure rate, indicating a trend of first rising and then falling. A multi-objective optimization was used to optimize the parameters, the influence of each factor, and the interaction on palletizing performance indexes. The test results showed that the detection time and the releasing height of the palletized trays presented a greater effect on the palletizing pass rate, whereas, the releasing height of the palletized trays, productivity and detection time presented a greater effect on the seed exposure rate. An optimal combination of parameters was 1.15 s for the testing time, and 1.10 cm for the releasing height. Correspondingly, the productivity was adjusted to 400, 500, and 600 trays/h under the optimal combination of parameters, where the palletizing pass rates were 99.33%, 99.50%, and 99.20%, respectively, and the seed exposure rates were 0.40%, 0.53%, and 0.70% respectively. Once the productivity was 400-600 trays/h, the palletizing pass rate was greater than 99%, and the seed exposure rate was lower than 1%. The rice planting automation can be widely expected to realize in the precision seeding production for rice seedling transplanting. [ABSTRACT FROM AUTHOR]

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Dalian University of Technology / Dalian Ligong Daxue Xuebao is the property of Journal of Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Liquid Crystal & Displays is the property of Chinese Journal of Liquid Crystal & Displays and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Current transportation of feed with high labor intensity has posed a great challenge on the popular aquaculture production in a timely manner at present, particularly on the pond culture. Furthermore, the quantity of delivered feed per run cannot be precisely controlled in the previous generation of widely-used feeding machines without a weighing device. In addition, the lacking of a digital control device has made feeding system difficult to be integrated into the management system in precise agriculture. The manual operation of feeding machines on site has not been feasible for large-scale farms, including a large number of ponds. In this study, a full-automatic precise feeding system was designed to improve the mechanical, automatic control, and information management in digital agriculture using cloud analytics. Four types of subsystems were firstly proposed, including mechanized operation, accurate measurement, automatic control, and digital integrated management, according to functional requirements in the need of large-scale pond aquaculture production. The system structure was based on the concept of "control was local and management was deployed in the cloud". A fully mechanized operation was realized using a large-capacity silo, and pneumatic conveyor to throw the feed. As such, the previous screw conveyor was replaced to carry the feed from the bulk truck to the silo. Three load cells were mounted on the bottom of support pillars to measure the weight of the silo. The remaining feed quantity was obtained by subtracting the weight of fixed mechanical parts from the total weight of the silo. The feed was firstly loaded into the delivery pipe through the unloader and then was blown to the inlet of the spreader through the air flow generated by the blower. A high-speed spreader was utilized to produce the centrifugal force for the spread of feed far away. A programmable logic controller (PLC) was also designed to accurately adjust the feed quantity of each feeding task, according to the preset parameters. The specific feed weight was also real-time collected from the weighing unit in the fully automated system of the feeding machine without manual operation. The local control center was constructed to realize the integrated management of the feeding task. The accurate docking of control and information management system was selected to implement the feeding control and production management. The feeding process was visualized to serve as efficient management tools using video monitoring equipment. The performance of the system was finally tested to achieve the designed goal. A demonstration base of full-automatic feeding and breeding was constructed with an area of 800 hectares in a large-scale breeding factory, including 90 feeding machines, 90 control cabinets, 5 zone control centers, and one management platform. An unmanned feeding was basically realized using the present system. The labor intensity was reduced by 70%, compared with the conventional feeding mode with a small feeding machine and manual operation. Real-time monitoring of feeding quantity was also realized in each pond for precise feeding, where the feed consumption was saved by 3%, indicating excellent performance. This finding can provide a promising application to the mechanized operation and automatic control system in large-scale pond culture [ABSTRACT FROM AUTHOR]

Identification of screen breakage in a hammer millis relying mainly on the manual feed sampling currently in Chinese feed industry. There are four disadvantages in the manual selection for the feed via artificial senses:a )Human errors and failings easily occurred in the mechanical detection of online system; b)Low efficiency is difficult to meet the requirements of automatic production in modern agriculture; c)High misdetection rate can result in the unqualified granularity of product; d)The procedure is costly, time consuming and labor intensive, sometimes involving hazardous chemicals. In this study, an online automatic identification system mounted on a novel sampling mechanism was established for the rapid and accurate detection of screen breakage in a hammer mill using imaging technology and machine vision. Three key parts were designed in the device, including sampling mechanism, screening mechanism, and image acquisition. Specifically, the sampling mechanism mainly consisted of a chute feeder, and automatic sampling components. The screening mechanism was composed of a vibrating feeding device, screen components, and feeder base. The platform of image acquisition included camera bellows, cloud platform, and complex optical assembly, such as camera, lens, as well as an annular LED light source. The sampling mechanism was selected to automatically select feed samples in real time. The screening mechanism was applied to screen and separate the obtained samples, thereby transfer the samples to the next mechanism. The platform of image acquisition was then applied to collect the image of particles in the samples. A Siemens S7-200 PLC programmable controller was applied to realize automatic control in the whole system, including sampling, sample screening, vibrating, and image collecting. Python language was used for the image processing and programming, graying, denoising, and binarization that contained in image preprocessing, where the contour of large particles and the minimum circumscribed rectangle were determined during the program. The equivalent diameter of projected circle and the minimum area of circumscribed rectangular for the screened large particles were taken as the characteristic parameters, and the threshold. K-nearest neighbor and radial basis function support vector machine were utilized to establish the identification model of screen breakage. The accuracy rates of threshold model were 98% and 93% for the diameters of 1.0 and 2.0 mm in the screen identification. The recognition model established by the threshold was not reliable to deal with the experimental data, due to the different distribution of dataset. The accuracy rates of KNN(K-Nearest Neighbor, KNN) model were 94% and 96% for the diameters of 1.0 and 2.0 mm in the screen identification, when k=3, and the input parameters of the nearest neighbor KNN model were set as the average diameter of projected circle and the average minimum of circumscribed rectangular area. When the input parameters of the radial basis kernel function support vector machine (RBFSVM) model were set as the average diameter of projected circle and the average minimum of circumscribed rectangular area, and the optimal penalty coefficient and gamma parameters (C, g) were (2-5, 2-7) and (2, 2-1), respectively, the recognition accuracies of RBFSVM model were 89% and 91% for the diameters of 1.0 and 2.0 mm in the screen identification. As such, the KNN recognition model was determined as the recognition of system, in case there was no significant difference between the running speed of KNN and RBFSVM models. The newly developed device can provide a promising technical support to the online automatic identification of screen breakage in a hammer mill. [ABSTRACT FROM AUTHOR]

Harvesting of the fresh fruit is remains heavily reliant on manual labor. It is the most time-consuming and laborious part of the whole fruit production process, which accounts for about 40% of the total workload. Therefore, automatic fruit harvesting technology and agricultural picking robot become a focus of research, and one of the key questions is how to design an end-effector of harvester suitable for specific fruits without damaging fruit during the picking process. A pneumatic sucking-gripping integrated non-destructive end-effector for tomato was developed and a non-destructive control method was proposed in this study. Firstly, an innovative multi-link 3-finger mechanism with spatial envelop was designed, which was arranged symmetrically on 3-finger type slide guide air gripper and driven by it. The vacuum cup was fixed in the center of three claws and was hinged to claws through multi-linkage. Based on this structure, the degrees of freedom (DOF) of vacuum cup was limited to the axial direction of air gripper, when three claws opened or closed. Thus, the two motions of pulling and gripping the fruit which was sucked by vacuum cup were driven by single active component in order. Secondly, the structural parameters of end effector with maximum envelope range of 156 mm and the maximum moving distance of sucker 38.7 mm are determined by establishing of kinematic model. Meanwhile, the relative relation between the motion velocity and acceleration of each component was obtained based on ADAMS kinematics and dynamics simulation analysis, as well as the relative relation between the holding force and pneumatic system pressure and fruit size. Thirdly, an electro-pneumatic system of end-effector with pressure feedback and pressure continuous regulation function was built. The Arduino Due programmable controller was used as the controller to control the proportional pressure regulating valve, so that the clamping force can be adjusted continuously in real time. In addition, FSR-402 pressure sensors were placed inside the three gripper fingers to detect the clamping force of each finger in the picking process. By analyzing the time domain signal of the digital quantity of the pressure sensors on the gripper fingers under the two slip conditions of the linear movement and rotation of the fruit relative to the gripper fingers, the dual-threshold slip judgment algorithm based on dynamic standard deviation rising fluctuation node and non-destructive picking control strategy based on slippage criterion and threshold of damage limit pressure were presented. Finally, the actuator performance test was carried out in the vegetable planting base of Bishan District, Chongqing, China. 204 ripe tomatoes of Hongyun 712 cultivar with outer diameter from 50 to 100 mm were selected for field trials. The indexes of picking success rate was defined to evaluate the performance of end-effector. The direct damage rate and 72 h browning rate was used to measure the performance of non-destructive clamping control method. The experimental results showed that the picking success rate was 96.03% of this actuator, direct damage rate was 1.58%, 72 h browning rate was 1.76%, and time consuming of one picking process was 5 s, which demonstrated the picking end-effector could sufficiently meet the usage demand of fruit picking robot. [ABSTRACT FROM AUTHOR]

Copyright of Cotton Textile Technology is the property of Cotton Textile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Kelp drying plays an important role in kelp processing and storage. However, there are some challenge issues in the kelp drying, such as high labor cost and high power consumption. In order to solve these issues in kelp drying, reduce the labor intensity, save power consumption, and improve the quality of products, a new type of sea-belt drying system combining the natural drying method with the heat pump drying method has been proposed. The new system is based on a task force and cascading design and consists of 5 parts, namely drying room, heat pump room, palletizing device, bridge part and control room. The automatic control system for the kelp drying includes data communication function, dry rod position tracking function, and environmental parameter measurement function. Without the manual labor, such as transport and tumble the fresh kelp, 50 drying rods hanging 100 kg of fresh kelp are automatically lifted to the drying room, a support frame with a length, width and height of 34.5 m × 6 m × 6.5 m for natural drying. The Siemens programmable logic controller (PLC) is used to communicate with the G120 inverter. The Universal Serial Interface (USS) protocol is employed to achieve long-distance acceleration and deceleration of the target position. The Process Field Bus (PROFIBUS) protocol is utilized to communicate with the Sick barcode positioning sensor to ensure accurate positioning of the drying rod. The rod track is used to synchronize the running motor and position the palletizing equipment. The limit switches are used to generate the trigger signal for kelp transmission from the drying room to the heat pump room, that is, the automatic bridge function. The heat pump drying method is to ensure the moisture content of kelp drying achieving high quality after the natural drying procedure. After completing the design of the automatic control system, several kelps are selected as the experimental samples. The test results showed that the walking motor can be adjusted by frequency conversion. The maximum speed is 20 m/min, the minimum speed is 3 m/min, and the maximum efficiency can be achieved before the target position 50 cm to start the deceleration. The distance between the two drying rods in the drying chamber is 37 cm and can also be precisely located. After the natural drying procedure by the sun-drying and air-drying actually, the moisture content of kelp is about 60 %. When the natural drying level (subject to the sunlight-drying degree and air-drying degree) is insufficient, the kelp should be transfer from the drying room to the heat pump room for further drying. The rails of the drying chamber must be connected to the rails of the heat pump chamber. Then the drying rods hanging the kelp automatically are transferred to the support frame in the heat pump room with a length, width and height of 6.5 m × 6 m × 5.6 m. The distance between the two drying rods is 12 cm, which can be precisely located. The moisture content of kelps are dried to about 15.2% eventually, without sediment, impurity rate of 0%, grade I. The whole operation time is about 5.7 h. The results showed that the novel kelp drying system can achieve high quality products with very low energy consumption and labor cost. In addition, it can be used as a reference in the algae processing industry. [ABSTRACT FROM AUTHOR]

Copyright of Cotton Textile Technology is the property of Cotton Textile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

According to the actual needs of small and medium-sized farms, an automatic control system for eco-environmental monitoring and cleaning was designed with PLC (programmable logic controller) as the core controller. The system was composed of subsystems such as sunshade, fan unit, spray system, manure scraper, and flushing control system. According to the detected value of ecological environment parameters such as temperature, humidity, the ammonia concentration in the pigsty, PLC and human-machine interface controlled the subsystems to achieve the regulation of the environmental parameters for improving the survival rate of piglets and reducing the incidence of pigs, resulted in realize the automatic breeding of pigs. According to the different temperature requirements of pigs in different growth stages, temperature-sensitive resistors were used to measure and control the temperature in different areas of the pigsty. Because the resistances of the temperature-sensitive resistor and the changes of the temperature were non-linear to achieve accurate temperature measurement, a simple resistance-voltage conversion circuit was designed and the measured value of the temperature-sensitive resistor was piecewise linearized in the PLC program design. The test results showed that the processing method made the temperature measurement accuracy reach ±0.2 ℃, which fully met the requirements of the control system. Because the PLC analog input module used in this system had only 4 input channels and the temperature and humidity analog signals had 16 channels. In order to reduce the production cost of this system, a 16-channel analog time-shared data acquisition circuit was designed in this study. This circuit was mainly composed of two CD4052. The two output switch signals of the PLC were converted into TTL (transistor-transistor logic) signals as the strobe address signals. Because the output signal of the ammonia concentration sensor used the MODBUS-RTU communication mode, this article gave a program design method to achieve this communication in Delta PLC. Due to the large space in each area of the pigsty, the detection value output by each sensor was related to the location where it was installed. In order to realize the reasonable detection of the environmental parameters in all areas of the pigsty, a multi-sensor adaptive weighted average fusion algorithm was adopted in this study, and a PLC program design method of the algorithm had given. The test results showed that using the data fusion algorithm, the minimum value of the total variance of the temperature measurement values in the piglet’s living area was about 0.012 5 at 20 ℃, and the variance was 0.856 2 when using the arithmetic mean. When the ammonia concentration was around 15 mg/m³, the minimum value of the variance of the ammonia concentration measurement value of the whole pigsty using the data fusion algorithm was 0.040 6, and the arithmetic mean was 0.954 8. This showed that with the data fusion algorithm, the variance of the measured values of the parameters in each area was much smaller than the variance when the arithmetic mean was used. Each subsystem ran reliably during the test and achieves the design goals. The control system had a simple structure, it was easy to install, debug and maintain, and had a low cost. It could greatly reduce the labor intensity of workers, save manpower, and reduce environmental pollution. Its high application value was especially suitable for small and medium-sized scale breeding farms. [ABSTRACT FROM AUTHOR]

In order to improve the efficiency of tree planting ⑽d the automation 肋d intellectualization level of ^ planter with little damage to the surrounding primary vegetation is designed in this paper. On the basis of kinematics analysis of planting mechanism of tree planter, a control system scheme based on programmable logic controller (PLC) is provided. The work program of hydraulic control system of tree planter, automatic operation cycle scheme of tree planter and plant spacing control scheme are emphatically studied. The results show that the control system of intermittent hole digging and planting mechanism can realize the control of moving intermittent hole digging and planting, intelligently adjusting planting depth and precise plant spacing. The operation of each mechanism is reasonable and non - interference, and the planting efficiency is 400 ~ 500 plants per hour. This provides a way for the development of tree planter to automation and intellectualization. [ABSTRACT FROM AUTHOR]

Greenhouses in remote areas have difficulty to access power. This paper aims to resolve this problem with a new system that can supply electricity to low-power devices such as energy-saving lamps, temperature and humidity monitoring system, digital equipment and other electrical equipment in greenhouses in remote areas. Current power supply to greenhouses uses distributed energy sources from wind and solar, which are not portable and susceptible to environmental changes. Under certain circumstances, power supplied from these systems is insufficient or even fails. As such, there is an increase in developing portable power generation systems. For example, in China, portable multi-purpose photovoltaic power generation system had been developed for agricultural production using remote-control system (programmable logic controller, PLC) to monitor pumping stations. There was also portable multi-power source power generation system to compliment wind power, solar energy and hand-cranked energy generation. Devices to generate power using the difference in temperature between human body and ambient environment exist, which are powerful enough to power LED lights. Another portable device is to generate thermal energy by burning combustibles in the field. All these portable devices have their pros and cons and the purpose of this paper is to present a new portable thermoelectric power generation system. The size of the system was 20 cm × 20 cm × 5 cm weighted 2580 grams, and its energy sources was from combusting biomass. A flat heat pipe was used for thermal conduction. We simulated performance of the system using the ANSYS, and set an experimental platform to test it. The experimental data showed that the highest temperature at the hot end of the system was 270.1 ℃, the maximum power output was 10.7 W, and the electrical efficiency was 5.73%. The results also revealed that the system had advantages of high hot-end temperature and high thermoelectric efficiency. It can generate electricity under extreme conditions in remote areas. Numerical and experimental analysis of various inputs and outputs indicated that the system is portable, the hot end temperature is high, and the thermoelectric efficiency is high. It provides a baseline for study of portable power generation system. [ABSTRACT FROM AUTHOR]

In order to enhance the intelligent performance of the handling robot and strengthen the monitoring capability of the control center to the industrial field, an intelligent handling robot experiment platform has been designed according to the practical production demands of the intelligent manufacture enterprises along with the scientific research projects undertaken by the laboratory. It integrates multiple advanced technologies together, including binocular vision, handling robot, as well as industrial wireless. As for the platform, the PLC is taken as the main controller of the intelligent handling robot, the binocular vision is applied for classifying and positioning the objects, the industrial wireless technology is adopted for realizing the data communication between the control center and the intelligent handling robot, the HMI is designed for displaying the running status of the intelligent handling robot remotely. The experiment shows that, the intelligent handling robot is able to detect, grab and handle the objects, meanwhile, the control center can perform real-time monitoring in industrial field. [ABSTRACT FROM AUTHOR]

Copyright of Cotton Textile Technology is the property of Cotton Textile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to improve the teaching effect of PLC 'Flip Classroom', a classroom teaching experiment system suitable for this teaching mode was designed. Firstly, according to the characteristics of classroom teaching and 'Flip Classroom' mode, the requirements for PLC experimental system were sorted out. Then, an experimental system that meets the requirements of 'Flip Classroom' teaching was designed by using computer, virtual simulation, wireless communication and other technologies, and the detailed ideas and processes of hardware and software design were given. Finally, the realization process and application effect of the total experimental system were expounded by taking 'Handling Manipulator' as an example. The realization and application of the experimental system solve the problem of separating practice from theory teaching in traditional classroom, and also greatly enhance students' learning interest and lay a foundation for good teaching effect. [ABSTRACT FROM AUTHOR]

Based on the research and optimization of the tension setting value calculation model of cold rolling annealing furnace. Using S7 -400 PLC, S120 frequency converter and PCS7 software platform, the closed-loop tension control system and automation network of annealing furnace are constructed to ensure the stability and reliability of the unit operation. By comparing tension setting with on-line monitoring of feedback curve, the analysis of sampling data of width and thickness of strip before and after entering furnace shows that the tension control of strip is stable and accurate, and the size of strip is almost unchanged. The annealing process index has been completed well, which meets the requirements of production design. [ABSTRACT FROM AUTHOR]

An integrated experiment system of water and fertilizer control based on PLC was designed. Fuzzy-PID controller was used to regulate water pressure and flow through constant pressure water supply system. EC value of water and fertilizer was adjusted by Venturi jet mixer, touch screen was used for operation and real-time monitoring. Precise fertilization was carried out, and the most suitable growth environment for crops was created. Based on the analysis of the system and the establishment of the EC control model, the model was established and simulated by using MATLAB. The simulation results show that the fuzzy PID control can significantly improve the overshoot and the time to reach the steady state, ie, the overshoot is reduced by 8% and the time to reach the steady state is reduced by 20 seconds. The system was debugged and operated in the test base. The overshoot is less than 2 %, and the EC fertilizer is stable within 60 seconds, which meets the requirements of the test system. [ABSTRACT FROM AUTHOR]

DeviceNet has characteristics of reliability, real-time and simple orperation, and is widely used in industrial control. In order to enable beginners to better understand communication mechanism and method of DeviceNet, an experimental system which can embody the characteristics of DeviceNet is designed. The hardware structure, communication configuration and programming method of the experimental system are introduced. Two experimental projects of PLG basic programming and DeviceNet network configuration are designed. The students can master the basic programming instruction, I/O configuration and communication configuration method by the PLC logic control program, and then the network configuration and programming are carried out, so that the communication mode between the controller and the equipment on the DeviceNet can be understood gradually. The experiment system cooperated with the course of “Industrial Communication and Network Technology” for many years, it can help students to understand of the abstract communication theory, and achieved good teaching effect. [ABSTRACT FROM AUTHOR]