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Aiming at energy saving and consumption reduction, this project applies the technology of combined heating and cooling heat pump to ecological building design. The combined hot and cold system is an integrated control system, which utilizes the solar system and heat pump technology (air source heat pump, water source heat pump) to complement each other based on changes in the outdoor environment, thus providing users with hot water heating and cold water cooling in winter. After installing a new heating and cooling system, coupled with well-equipped automatic control equipment, the heating coal consumption has been significantly reduced, and the emissions of CO2, SO2 dust, and other pollutants have also been correspondingly reduced. Compared with the cold and hot split supply system using electric refrigeration and thermal heating, the winter and summer sharing of the cold and hot combined supply device not only improves energy utilization efficiency, but also saves investment in heat source construction, thereby reducing costs and environmental pollution. [ABSTRACT FROM AUTHOR]

Aiming at the problems of the low efficiency of manual pesticide application in the greenhouse, the narrow operating space of plant protection machinery, and the possibility of poisoning the pesticide applicators due to the closed space, a high-pressure atomization spraying equipment for the greenhouse was designed. The spraying equipment adopts two-way communication between PLC and HMI to realize the adjustment of atomization pressure and atomization flow, and the control equipment completes automatic spraying. To determine the best working parameters of the spraying equipment, orthogonal tests were conducted with atomization pressure and atomization nozzle aperture as the test factors and the coefficient of variation of the fog volume distribution as the evaluation index. The optimum combination after parameter optimization was determined to be as follows: atomization pressure of 4 MPa, atomization nozzle aperture of 0.4 mm. The test results under the optimal parameters showed that the spray distribution coefficient of variation was 10.5%, and the uniformity of fog volume distribution was good to meet the requirements of spraying in greenhouses. [ABSTRACT FROM AUTHOR]

Cycle identification via the rainflow‐algorithm is implemented online in a model predictive controller (MPC) for Li‐ion batteries. This is achieved by externalization of the cycle identification from the optimization problem. The limitation for cyclic aging estimation due to short prediction horizons is overcome by updating and utilizing a State of Charge memory. Furthermore, a comprehensive plant model for Li‐ion batteries is presented with novel submodels for calendric and cyclic aging. The novel MPC is implemented in the ACADO Toolkit and tested with the aforementioned plant model. Simulation results indicate that—even without tuning—the novel MPC clearly outperforms a rule‐based controller and an extensively tuned MPC from literature. [ABSTRACT FROM AUTHOR]

In recent years, people are committed to developing new technologies and technologies for energy storage and conversion, environmental detection, high-performance sensors and energy security, and other aspects of the increasingly prominent problems in the field of environmental and biosafety. The purpose of this paper is to explore the manufacturing system and automatic synthesis equipment of carbon nanomaterials, understand the control device and control method, and analyze the structure and morphology characteristics of three kinds of carbon nanomaterials produced by carbon nanomaterial manufacturing system by X-ray diffraction and infrared spectroscopy. The results show that the carbon nanomaterial manufacturing system and automatic synthesis system in this paper solve the problems of high cost, low efficiency, and small scale of the existing carbon nanomaterials manufacturing and achieve the precision control of automatic production, so that the productivity is increased by 20%–35%, and the cost is reduced by 15%–30%. Therefore, they are widely used in the fields of science and technology, environmental protection, and intelligent manufacturing broad prospects. Carbon nanotube manufacturing equipment and automatic synthesis equipment have great production advantages, which can greatly improve the quality and efficiency of carbon nanomaterials. UPY, GO, and UGO carbon nanomaterials produced by carbon nanotube manufacturing equipment are not easy to fall off from the materials. When the wavelength is 500 nm, the absorption frequency of the three materials is the largest. With the extension of the spectral wavelength, the absorption frequency of the three materials is reduced by 52%, 33%, and 34.7%, respectively. [ABSTRACT FROM AUTHOR]

The increasing popularity and maturity of plasma actuators for many flow control applications requires a common standard for plasma actuator performance evaluation. In the present work, a comprehensive comparative study of existing and new evaluation measures is presented, based on results from identical plasma-actuator configurations. A power-flow diagram is introduced that covers the entire range of power stages from the energy source to the flow-control success. All individual power stages are explained, existing controversial definitions are clarified, and an evaluation guideline is applied to previously obtained data. Finally, the defined systematic analysis is applied to the results of a recently conducted plasma-actuator in-flight experiment. [ABSTRACT FROM AUTHOR]

The article describes the fabrication of Twisted Coiled Polymer Actuators (TCPA) and the different elements that compose it. Topics discussed include the initial TCPA manufacturing process, the use of an Arduino Mega with a stepper motor shield for the control system, and the major parts of the device including end plates and motors, carriage and rails, and sensor board.

Temperature in the creep area for piglets will decrease from birth to weaning. To reduce the consumption of electricity and meet the temperature requirement of piglets from birth to weaning, an experiment of variable power heating system of heat lamp compared with constant power heating system of heat lamp was conducted in a scaled pig farm in Northern China. Two units of farrowing room (one unit with 23 farrowing sows and 25 heat lamps of 250 W) in the pig farm were chosen for this study, except for heat lamps, hot water floor heating was provided for piglets. An automatic control system which was composed of ATS (air temperature sensor) and SCM (single chip microcomputer with PID (proportional, integral and derivative) control) and SCR (silicon controlled rectifiers) was used in the test unit and constant power heating system was used in the control unit. The temperature automatic control system can bear 10 000 W. In the test unit, temperature of 30.0 ℃ was set from piglets birth to the age of 7 days, and then reduce temperature by 2.0 ℃ every week till 21 days after birth. In the control unit, heat lamp was with constant power to heat piglets creep areas. Electricity consumption used in the test unit and control unit was recorded by two ammeters, respectively. Behaviors and temperatures in creep area of piglets were recorded and analyzed. Piglets performance was also recorded and analyzed. It was shown that during the first week after birth, both of the heat lamps in the test unit and in the control unit maintain full power operation, the average temperature right below the heat lamp (0.3 m high from the floor) was 27.4 ℃; during the second week, the average temperature right below the heat lamp for the test unit and the control unit were 27.2 and 27.5 ℃, respectively; during the third week, the average temperature right below the heat lamp for the test unit and control unit were 26.8 and 27.4 ℃, respectively. Floor temperature right below the test unit and control unit were 29.5-31.0 and 31.0-30.6 ℃, respectively. In brief, from birth to 21 days, floor temperature right below the heat lamp, side below the lamp and the slatted floor were 29.5-31.0, 28.9-29.5 and 22.9-23.0 ℃, respectively. Lying rates in different areas of right below the heat lamp, side below the lamp and the slatted floor were 40.7%-66.5%, 14.4%-33.4% and 0.9%-8.7%, respectively. Rates of survival of piglets (28 days weaning) in the test unit and control unit were 95.8% and 93.8%, respectively. Average daily gain of piglets (28 days weaning) in the test unit and control unit were 0.198 and 0.193 kg/(head·d), respectively. Using this kind of variable power heating system, the farrowing room can save 1.8 kW·h per lamp per day from 8 days to 14 days after piglets birth, and 2.7 kW·h per lamp per day from 15 days to 21 days after piglets birth. The energy consumption can be saved by 25.4% each batch of production based on 21 days weaning. On condition of electricity price of 0.5215 yuan/(kW·h), 25 heat lamps with 250 W in one farrowing unit and investment of one set of equipment of temperature automatic control with 2 980 yuan, payback period will be 2 a. The temperature automatic control system of heat lamp can not only save energy but also can improve piglets performance. [ABSTRACT FROM AUTHOR]

• Attributes of the trustworthiness of automated subways are grouped into automation- and service-related factors: 'automation trustworthiness' and 'service trustworthiness'. • Automation trustworthiness includes reliability and consistency of automation and operation. Service trustworthiness, on the other hand, includes reliability and reputation of problem detection, resolution and communication, and benevolence and integrity. • Both automation trustworthiness and service trustworthiness appear to significantly contribute to passengers' trust in automated subway services. • Both trustworthiness factors appear to negatively affect passengers' anxiety and fear, mediated by the passengers' sense of certainty and coping potential. Commuters worldwide can now travel to work using unmanned subway services while tourists may travel to holiday destinations on planes that employ automatic flight control equipment. More recently, autonomous buses have made their debut in several cities. Technological advances in transport services, however, are accompanied by challenges to passengers' perceived safety and the acceptability of the technology. While passengers' anxiety and fear appear to reduce their acceptance of new technologies, trust has been shown to positively affect their acceptance of automation and autonomous vehicles. In this vein, the present study investigates the trustworthiness of automated subway services in Korea with regard to passenger anxiety and fear. First, automated subway-specific trustworthiness factors are identified through exploratory factor analysis. Subsequently, the effects of the identified factors on passenger anxiety and fear are examined using structural equation modeling. The results indicate that attributes that contribute to the trustworthiness of automated subways are grouped into automation- and service-related factors: 'automation trustworthiness' and 'service trustworthiness', both of which appear to negatively affect passengers' anxiety and fear, mediated by the passengers' sense of certainty and coping potential. The negative effects of trustworthiness on anxiety and fear indicate that strengthening of the trustworthiness factors must be accompanied with technological advances in transportation. The implications for strengthening the trustworthiness of unmanned automated subways and other transport services employing autonomous features are presented, correspondingly, in this study. [ABSTRACT FROM AUTHOR]

Temperature in the creep area for piglets will decrease from birth to weaning. To reduce the consumption of electricity and meet the temperature requirement of piglets from birth to weaning, an experiment of variable power heating system of heat lamp compared with constant power heating system of heat lamp was conducted in a scaled pig farm in Northern China. Two units of farrowing room (one unit with 23 farrowing sows and 25 heat lamps of 250 W) in the pig farm were chosen for this study, except for heat lamps, hot water floor heating was provided for piglets. An automatic control system which was composed of ATS (air temperature sensor) and SCM (single chip microcomputer with PID (proportional, integral and derivative) control) and SCR (silicon controlled rectifiers) was used in the test unit and constant power heating system was used in the control unit. The temperature automatic control system can bear 10 000 W. In the test unit, temperature of 30.0 was set from piglets birth to the age of 7 °C days, and then reduce temperature by 2.0 °C every week till 21 days after birth. In the control unit, heat lamp was with constant power to heat piglets creep areas. Electricity consumption used in the test unit and control unit was recorded by two ammeters, respectively. Behaviors and temperatures in creep area of piglets were recorded and analyzed. Piglets performance was also recorded and analyzed. It was shown that during the first week after birth, both of the heat lamps in the test unit and in the control unit maintain full power operation, the average temperature right below the heat lamp (0.3 m high from the floor) was 27.4 °C; during the second week, the average temperature right below the heat lamp for the test unit and the control unit were 27.2 and 27.5 °C, respectively; during the third week, the average temperature right below the heat lamp for the test unit and control unit were 26.8 and 27.4 °C, respectively. Floor temperature right below the test unit and control unit were 29.5-31.0 and 31.0-30.6 °C, respectively. In brief, from birth to 21 days, floor temperature right below the heat lamp, side below the lamp and the slatted floor were 29.5-31.0, 28.9-29.5 and 22.9-23.0 °C, respectively. Lying rates in different areas of right below the heat lamp, side below the lamp and the slatted floor were 40.7%-66.5%, 14.4%-33.4% and 0.9%-8.7%, respectively. Rates of survival of piglets (28 days weaning) in the test unit and control unit were 95.8% and 93.8%, respectively. Average daily gain of piglets (28 days weaning) in the test unit and control unit were 0.198 and 0.193 kg/(head·d), respectively. Using this kind of variable power heating system, the farrowing room can save 1.8 kW·h per lamp per day from 8 days to 14 days after piglets birth, and 2.7 kW·h per lamp per day from 15 days to 21 days after piglets birth. The energy consumption can be saved by 25.4% each batch of production based on 21 days weaning. On condition of electricity price of 0.5215 yuan/(kW·h), 25 heat lamps with 250 W in one farrowing unit and investment of one set of equipment of temperature automatic control with 2 980 yuan, payback period will be 2 a. The temperature automatic control system of heat lamp can not only save energy but also can improve piglets performance. [ABSTRACT FROM AUTHOR]

Highlights • A novel adaptive tracking control method is proposed for a tower crane system. • The proposed control method can obtain better tracking performance for tower crane systems in complex working environment. • The payload swing can be effectively suppressed during the tracking process. Abstract As an efficient transportation tool, a tower crane is widely used in construction sites. To improve the working efficiency, some automatic control methods have been proposed for tower crane systems, including some open loop methods, such as input shaping methods, trajectory planning methods, and so on. However, generally, tower cranes usually work in outdoor environment, which are sensitive to unavoidable external disturbances. Additionally, accurate system parameters are hard to obtain, which increases the control difficulty of the tower crane system. Considering these factors, in this paper, we propose an adaptive tracking control method, which achieves satisfactory tracking performance w.r.t. parameter uncertainties and external disturbances. Specifically, utilizing the passivity property, a shaped energy-like function is designed as a Lyapunov candidate, based on which, an adaptive tracking controller is proposed to deal with parameter uncertainties. Using Lyapunov stability analysis, together with LaSalle's invariance principle, the closed-loop system is proven to be asymptotically stable. At last, a series of experimental tests are implemented to illustrate the satisfactory performance of the proposed method. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate milk yield and frequency of visits to the milking station of primiparous versus multiparous cows at different stages of lactation on farms with automatic milking systems (AMS) in the Upper Midwest United States. Forty farms were included in the study, and daily AMS software data were collected for 18 mo. For the investigation of milk yield and milking visits, stage of lactation was categorized into 14 periods, 7 d in length for the first 28 d in milk (DIM) and 30 d in length thereafter until 328 DIM. Cow traffic flow to the AMS (free or guided) was included in the model. For the evaluation of failures and refusals, stage of lactation was categorized into 6 periods, 7 d in length each for the first 28 DIM, and 2 periods of 150 d in length each thereafter until 328 DIM. Failures are milking station visits where a cow fails to be milked due to lack of machine attachment although it is time for the cow to be milked. Refusals are milking station visits before adequate time has passed since previous milking, thus the cow leaves the milking station without being milked. Data from lactation days beyond 328 DIM were excluded from the study. Primiparous cows in free-flow systems produced less milk than multiparous cows until the 11th stage of lactation and produced more milk from the 12th stage until the end of the study period. Primiparous cows in guided-flow systems produced less milk than multiparous cows all 14 stages of lactation, but were approaching the milk yield of multiparous cows at the end of the study period. This was a biologically normal lactation curve for primiparous cows. However, estimated peak ratio (primiparous vs. multiparous cows' peak milk yield) was lower than industry standards. Both traffic flow systems had fewer milking visits for primiparous cows compared with multiparous cows in early lactation. This lower milking frequency persisted until the 11th stage of lactation in free-flow systems. In guided-flow systems, primiparous cows were milked less frequently until the 5th stage of lactation, had similar milking frequency in the 6th stage of lactation, and were milked more frequently thereafter. Failures were greater for primiparous cows during all stages of lactation. However, the greatest differences were detected in the early stages of lactation. Primiparous cows had 0.067 more failures/cow per d on average than multiparous cows during the 1st wk of lactation. For the remaining lactation stages, differences in failures ranged from 0.003 to 0.039. Refusals were less frequent (0.4 to 0.6/d) for primiparous cows during the first 2 wk of lactation, similar for the 3rd wk of lactation, and more frequent for the remaining lactation stages (0.10 to 0.14/d). Failures and refusals were only evaluated in free-flow systems. These findings appear to indicate a potential lagging performance for primiparous cows in early lactation as compared with multiparous cows. Additional investigation into improving the adaptation of primiparous cows to AMS in early lactation may be warranted [ABSTRACT FROM AUTHOR]

The purpose of this work is to improve the understanding of the role of venetian blinds as a part of a building energy system. This is valuable for both designing automatic control of blinds and advising occupants towards energy-efficient use of manual blinds. A new strategy to control venetian blinds developed in the work aims at minimizing energy consumption by controlling blinds in a way that takes into account not only the effect of blinds on both solar transmission but also the effect on heat loss through windows. Annual computer simulations were performed to calculate the effect of blind use patterns on heating, cooling and lighting demand in four European climates in three single-family houses. The results show that the use patterns of blinds have a significant effect on energy consumption and that the new control strategy leads to lowest total energy consumption in all of the simulated buildings in all four climates. In contrast, a completely passive strategy—although very common in reality—consumes the most; depending on the climate and window size, total consumption is highest either when the blinds remain continually lowered and closed or continually raised. Occupants should be advised about the potential to save energy by changing blind use behaviours, also in the heating season. [ABSTRACT FROM AUTHOR]

Highlights • This paper proposes a general control logic framework based on human cognitive model (IDA). • In order to describe the control process in reliability analysis, the traditional GO-FLOW modeling theory is extended. It clearly describes the information interaction process between the control system and the controlled system. • In this paper, a hierarchical modeling and analysis method is used to achieve hierarchical GO-FLOW modeling. • The implementation of the above method is verified through a case study of chemical and volume control system (CVCS) in NPP. Abstract Reliability of system, structures and components plays a crucial role in ensuring the safe and stable operation of nuclear power plants. With the widespread application of automation in nuclear power plants, the role of the operator in main control room has been changing from actual implementation of control to supervision of the control process. Reliability monitoring of automatic control components and systems provides an insight of the ability of plant systems in realizing their expected goals over time. This paper presents an extension of GO-FLOW methodology in modeling automatic control component and systems from the perspective of cognitive process. Through the concept of hierarchical modeling, this paper designs an improved GO-FLOW model hierarchical modeling and analysis framework, which further increases the feasibility of modular modeling and model readability. Taking CVCS of nuclear power plant as an example, considering the control of ACP, the analysis and calculation of several scenarios are carried out in this study. In the course of the analysis, it was verified that the model is able to update automatically and realize the real-time system reliability monitoring function. The approach proposed in this paper is a general technique which could be extended further to describe more complex control logic. [ABSTRACT FROM AUTHOR]

Maize inspection is an important and time-consuming task in the domain of food engineering. The human-based inspection strategy needs to be brought up to date with the rapid developments in the maize industry. In this paper, an automatic maize-inspection machine is proposed. Our proposed machine integrates several new designs in terms of both hardware and software components. First, a gravity-based dual-side camera design expands the machine's field-of-view to evaluate maize kernels more thoroughly. Second, touching kernels are pre-processed using a new k-means clustering guided-curvature method, which can improve the robustness of our machine. Next, a deep convolutional neural network, which has shown promise for application in image processing, is embedded into the system to evaluate maize kernels. In this work, the ResNet, which is a deep convolutional neural network architecture, was trained by fine-tuning with 1632 images. It achieved a 98.2% prediction accuracy for 408 test images, which outperforms existing approaches. Highlights • Design a dual-camera based synchronised maize inspection machine. • Applied an improved background removal method. • Propose a K-means-guided curvature method to segment the touching kernels. • Integrate deep convolutional neural network in the maize inspection machine. [ABSTRACT FROM AUTHOR]

In this paper, a novel switching event-triggered synchronization scheme is established for chaotic networked control systems with different dimensions. First, a reduced-dimension observer is constructed to help the response system estimate all the states of the drive system. Next, a switching event-triggered networked control method which depends both on relative error and absolute error of the sampled-data is designed to reduce the burden of network bandwidth effectively while ensuring the desirable synchronization performance. On the basis of the above, some sufficient synchronization criterions are derived in the form of linear matrix inequalities. Finally, the numerical simulation is carried out to demonstrate the effectiveness and superiority of the synchronization method. [ABSTRACT FROM AUTHOR]

The optimal control of the heating, ventilation, and air-conditioning (HVAC) system in buildings has a significant energy saving potential and therefore is of a great practical interest. An event-based HVAC control adjusts control actions when certain events occur, which may be faster and more scalable than state-based or time-driven control methods. However, events may capture either local or global changes in the rooms. The choice of events is a tradeoff between the computational efficiency and the control performance. This challenging problem remains open. We consider this as an important problem in this paper and make three major contributions. First, we define local and global events for the HVAC control problem. The complexity of these event-based control policies is defined. Second, based on hypothesis testing, we develop a method to select events that capture a sufficient state information and with a relatively small event space. Third, we demonstrate the performance of this method on two groups of examples, including one group of small-scale problems for the proof of concept and the other group of large-scale problems in the HVAC control. It is shown that our method outperforms the Levin search, which is a traditional complexity-based search method and finds event-based HVAC control policies with a good performance. Note to Practitioners—When there are multiple rooms in a building, the HVAC control may achieve a significant energy saving and an indoor comfort satisfaction in the same time through exploring the coupling among the rooms. By appropriately defining the events, the size of the event space is usually much smaller than the state space. Therefore, an event-based control is more scalable and preferred in practice. Local events capture the state changes of rooms in a small neighborhood, which leads to a small event space but limited information. Global events capture the state changes of rooms in a large neighborhood, which leads to more information but a large event space. It remains open how to select events in large-scale HVAC control problems, especially when the computing budget is limited. In this paper, we define the complexity of an event-based control policy by the number of neighboring rooms considered. We develop a method based on hypothesis testing to select events with a proper complexity in order to achieve a good system performance. The performance of this method is demonstrated on an HVAC control problem. [ABSTRACT FROM AUTHOR]

Low-level control of autonomous underwater vehicles (AUVs) has been extensively addressed by classical control techniques. However, the variable operating conditions and hostile environments faced by AUVs have driven researchers towards the formulation of adaptive control approaches. The reinforcement learning (RL) paradigm is a powerful framework which has been applied in different formulations of adaptive control strategies for AUVs. However, the limitations of RL approaches have lead towards the emergence of deep reinforcement learning which has become an attractive and promising framework for developing real adaptive control strategies to solve complex control problems for autonomous systems. However, most of the existing applications of deep RL use video images to train the decision making artificial agent but obtaining camera images only for an AUV control purpose could be costly in terms of energy consumption. Moreover, the rewards are not easily obtained directly from the video frames. In this work we develop a deep RL framework for adaptive control applications of AUVs based on an actor-critic goal-oriented deep RL architecture, which takes the available raw sensory information as input and as output the continuous control actions which are the low-level commands for the AUV’s thrusters. Experiments on a real AUV demonstrate the applicability of the stated deep RL approach for an autonomous robot control problem. [ABSTRACT FROM AUTHOR]

Developing mechanical devices to restore natural locomotion for transfemoral amputees still raises many challenges. One of them is the development of an efficient control strategy for the prosthesis active joints, with the objective of making it flexible and intuitive to use. This paper focuses on the transfemoral CYBERLEGs Beta-Prosthesis, an actuated elastic ankle–knee prosthesis embedding bio-inspired mechanisms targeting the minimization of its total power consumption. We provide the development of a bio-inspired, torque-based, controller for this device, requiring no torque sensing. Torque control is achieved by means of static modelling of the prosthesis geometrical and elastic relationships. Bench testing of the prosthesis was performed to show that this static model is able to accurately predict the actual behaviour of the device. The model was then used to build the low-level controller of the prosthesis, converting desired torques into reference positions for the joint actuators. Next, a walking experiment with a transfemoral amputee was conducted to assess the feasibility of a torque-based control approach for the prosthesis, with a simple high-level controller combining reference torque trajectories and bio-inspired joint impedances. Results validated the use of our static model for implementing the low-level controller of such an elastic and redundant prosthesis. [ABSTRACT FROM AUTHOR]

In accordance with the occupational health and safety standards currently in force, the safety parameters that define the underground atmosphere (mainly temperature and gases) will be monitored during the closing of mines, both during the proper closing and the preservation stage, as well during the temporary or permanent closing of the mine areas damaged during the mining period. The solution intends to warn against the hazards of undergrounds fires and gas and powders explosions; it consists in the automatic sampling and processing of information on the evolution of temperature and gases inside goofs and closed underground areas. [ABSTRACT FROM AUTHOR]

White button mushrooms, one of the most commonly and widely consumed mushrooms worldwide, require grading before entering the market. The diameter of the pileus is an important factor that affects the selling price. The aim of this study is to develop an automatic sorting system for fresh white button mushrooms based on image processing according to the pileus diameter. First, an automatic sorting hardware system is designed that consists of a conveying mechanism, an image acquisition system, a control module and an actuator. Second, we present an image algorithm based on the watershed method, Canny operator, OR operation, and closed operation to determine the pileus diameter of fresh white button mushrooms. The algorithm eliminates the influence of the shadow and petiole on the image. Third, a precise control strategy is introduced based on the conveyor speed, distance between the trigger and the flap piece, trigger time and algorithm processing time. Finally, we present analysis and control software based on OpenCV 2.4.10 and Visual Studio 2010. In the experimental portion, a prototype system was tested to validate its applicability and reliability by the grading performance and results. The experimental results showed that the average maximum grading speed was 102.41 mushrooms/minute, the accuracy of grading was 97.42%, the damage rate was 0.05%, and the undetected rate was 0.96%. Relative to manual grading, the grading speed was improved by 38.86%, and the accuracy was improved by 6.84%. The system can operate stably and continuously. For long-duration grading in particular, the advantage of the automatic sorting system is apparent because it eliminates labourer fatigue. The system achieves online automatic sorting and grading of fresh white button mushrooms with minimal destruction. [ABSTRACT FROM AUTHOR]

Inflatable membrane structure employs flexible membranes as main constructive materials, as well as pressurized gas in the membrane envelope aiming to provide the bearing capacity and structural integrity. Therefore, the internal pressure control and load simulation method are very significant to estimate the structural behavior of inflatable membrane structure. This paper presents an automatic system for pressure control and load simulation of inflatable membrane structure, including a pressure control subsystem and a load simulation subsystem. For pressure control, internal pressure of inflatable membrane structure is controlled by switching the high-speed on/off valves which connect air compressor to the structure. For load simulation, wind pressure and wind suck loads, acting on membrane surface in the normal direction, are simulated by controlling the solenoid valves to allow the vacuum pumps to inflate air into or pump air out from the load simulation chamber which is closely connected to inflatable membrane structure with an airtight space. More importantly, the coupling control of two subsystems can be automatically carried out to simulate the inflatable membrane structure under resisting the varied wind loads. These above actions are automatically performed based on the control logic coded in software module. In order to estimate the proposed automatic system, the internal pressure control, load simulation and coupling control tests were performed on a square double-layer ETFE (ethylene tetrafluoroethylene) cushion model. Control performance and accuracy of the proposed system are proved by analyzing the measured pressures. It is thus demonstrated that the proposed automatic system is considerably automatic, accurate, efficient and reliable for pressure control and load simulation of inflatable membrane structures. [ABSTRACT FROM AUTHOR]

In order to study the influencing factors of speed control of large particle seed metering device, by using response surface method, it is obviously that coefficient of variation of row spacing(C) is effected by the interaction between the belt speed and the given impulse, especially the belt speed is the main influencing factor.Experiment results showed that the socket-roller seeding device could achieve the seeding test successfully,stably and its performance index accord with the standard of single grain precision seeding experiment. Thus, the precision seeding could be achieved by the device. [ABSTRACT FROM AUTHOR]

During the refuelling process, the float switch closes when the internal tank liquid level reaches the highest level, but the automatic control valve cannot be closed simultaneously. If the delay time is too long, it may lead to an oil spill accident. In this paper, we analyzed the structure and basic working principle of the liquid level control. In addition, the flow of the automatic control valve, the force condition of the value core, the time required for closing the value, the speed and accelerated velocity of value core movement were theoretically studied according to the fluid momentum theorem and the kinematic equation of the valve closing process, which is of great practical significance for advancing research level of liquid level control valve. [ABSTRACT FROM AUTHOR]

At present, all kinds of liquid level control system is widely used in ground and underground storage tanks and other containers, which plays an important role to ensure the safety of production. Thus, it become an indispensable device of modern oil production and storage. In this paper, the governing equations of the internal flow field of the automatic control valve are established by using the basic theory of computational dynamic fluid and the RNG two equations turbulence model. And, the internal flow field of the automatic control valve under steady working state is simulated by using Fluent CFD software. Then, the pressure diagram, velocity profiles figure, velocity vector diagrams were obtained. It is believed that the research results of this paper have reference value for the further optimization of liquid level control valve. [ABSTRACT FROM AUTHOR]

Liquid level control value is widely used in the process industry to control internal liquid height as pipe flow control component. During the operation of the liquid level control valve, the force condition of the value core directly affects the stability of the valve works. Therefore, it becomes the important factors in the design of the spring components of the liquid level control valve. In this paper, the internal flow field of the automatic control valve during closing process is simulated by using Fluent CFD software. The numerical simulation results show that in the process of closing the automatic control value, the water hammer phenomenon will be occurred at the beginning stage. With the continuation of the valve closing process, the pressure in upper chamber of the value core and internal chamber are rapidly reduced and tend to be gentle, while the pressure difference increases gradually. What is more, the flow of throttle gradually increases, and the inner chamber of the valve core appears small disturbance. These conclusions provide a theoretical basis for the technical design and improvement of the control valve. [ABSTRACT FROM AUTHOR]

The use of process bus modern technology in accordance with the IEC 61850 protocol allows performing modern measurement and improving the protection automation system. It also allows for the integration and complex building of functional automation and control systems based on network devices in Ethernet technology. The paper presents measuring tests of a process bus equipment and the operation of protection functions based on measurements. [ABSTRACT FROM AUTHOR]

This paper proposes an improved input shaping scheme for an efficient sway control of a nonlinear three dimensional (3D) overhead crane with friction using the particle swarm optimization (PSO) algorithm. Using this approach, a higher payload sway reduction is obtained as the input shaper is designed based on a complete nonlinear model, as compared to the analytical-based input shaping scheme derived using a linear second order model. Zero Vibration (ZV) and Distributed Zero Vibration (DZV) shapers are designed using both analytical and PSO approaches for sway control of rail and trolley movements. To test the effectiveness of the proposed approach, MATLAB simulations and experiments on a laboratory 3D overhead crane are performed under various conditions involving different cable lengths and sway frequencies. Their performances are studied based on a maximum residual of payload sway and Integrated Absolute Error (IAE) values which indicate total payload sway of the crane. With experiments, the superiority of the proposed approach over the analytical-based is shown by 30–50% reductions of the IAE values for rail and trolley movements, for both ZV and DZV shapers. In addition, simulations results show higher sway reductions with the proposed approach. It is revealed that the proposed PSO-based input shaping design provides higher payload sway reductions of a 3D overhead crane with friction as compared to the commonly designed input shapers. [ABSTRACT FROM AUTHOR]

In the foundation construction of large tidal current power station, the truss hanger system is designed to solve the problem that the weight of crane is large and the lifting capacity of cranes is insufficient. The design process of the truss hanger system is discussed. The finite element calculation of the truss hanger system is carried out. The stress test is carried out during the foundation construction. The result of finite element calculation and stress test in the process of foundation construction show that it is feasible and rational to adopt truss hanger system when the lifting system can be designed with small weight. [ABSTRACT FROM AUTHOR]

Classical input shaping is based on convolving a general input signal with a sequence of timed impulses. These impulses are chosen to match certain modal parameters of the system under control to eliminate residual vibrations in rest-to-rest maneuvers. This type of input shaping is strongly dependent on the system period. In this work, an adjustable maneuvering time wave form command shaper is presented. The equation of motion of a simple pendulum model of a crane is derived and solved in order to eliminate residual vibrations at the end of motion. Several cases are simulated numerically and validated experimentally on an experimental model of an overhead crane. Results show that the proposed command shaper is capable of eliminating residual vibrations effectively with a single continuous wave form command. The work is extended to include the effect of hoisting on the shaper performance. Several functions are used to simulate hoisting. To overcome the added complexity of hoisting on the system, an approximation technique is used to determine initial shaped command parameters, which are later used in a genetic algorithm optimization scheme. Numerical and experimental results prove that the proposed command shaper can effectively eliminate residual vibrations in rest-to-rest maneuvers. [ABSTRACT FROM AUTHOR]

In this work, different variants of a branch-and-bound procedure for yard crane scheduling at seaport container terminals and their effect on the terminal's performance are studied. In particular, this work investigates the level of detail needed to take the exact crane characteristics, e.g., movements and crane interference, into account in the scheduling algorithm. This is examined for four different automated yard crane systems with one or more cranes that operate on rectangular yard blocks with transfer positions at both ends of the block and with the yard blocks arranged orthogonally to the quay. Using a simulation model with realistic scenario data and an automated guided vehicles system for horizontal transport, the results are compared with respect to different key performance indicators, e.g., yard crane productivity and average lateness of jobs. It turns out that especially the consideration of crane interference leads to significant improvements in yard crane productivity. As a result of the long computation times for some crane systems that render the practical application of the algorithm difficult, an approximation procedure is also developed that generates good results in reasonable time and hence allows for real-time application at a container terminal. [ABSTRACT FROM AUTHOR]

This paper presents the design and the experimental results of a CMOS Automatic Control System (ACS) for the biasing of High-Electron-Mobility-Transistors (HEMT). The ACS is the first low-power mixed-signal Application-Specified-Integrated-Circuit (ASIC) able to automatically set and regulate the operating point of an off-chip 6 HEMT Low-Noise-Amplifiers (LNAs), hence it composes a twochip system (the ACS+LNAs) to be used in the Large Scale Polarization Explorer (LSPE) stratospheric balloon for Cosmic Microwave Background (CMB) signal observation. The hereby presented ACS ASIC provides a reliable instrumentation for gradual and very stableLNAs characterization, switchingon, and operating point (<4 mV accuracy). Moreover, it simplifies the electronic instrumentation needed for biasing the LNAs, since it replaces several off-the-shelf and digital programmable device components. The ASIC prototype has been implemented in a CMOS 0.35 μm technology (12 mm2 area occupancy). It operates at 4 kHz clock frequency. The power consumption of one-channel ASIC (biasing one LNA) is 3.6 mW, whereas 30 mW are consumed by a single LNA device. [ABSTRACT FROM AUTHOR]

Offshore drilling platform is a complex object that includes an integrated automation system, each element of which is the source of the risk of emergency situations occurrence. These elements include primary transducers such as sensors, actuating devices and the systems of automatic control and regulation, due to their potential possibility of incorrect response to emerging operating conditions. Implementation of these risks can lead to catastrophic consequences. An algorithm for risk management as an add-on centralized automatic management system of the drilling platform was proposed to minimize the risks and their consequences. The algorithm includes the identification of risks, their analysis, prioritization, risk management planning, the process of managing and monitoring the risk metrics, according to which the assessment of the quality and effectiveness of risk management is carried out. Planning of risk management includes the processes determining ways to manage, search for ways to reduce the risks, risk documenting and risk metrics. The algorithm is based on the analysis of scientific publications dedicated to the description of emergency situations on drilling platforms: their causes, course and consequences; database of design offices, as well as the author's own research conducted at several drilling platforms operating in the Black Sea shelf. [ABSTRACT FROM AUTHOR]

To perform plant-protection operations, an unmanned aerial vehicle (UAV) based automatic control spraying system was designed in China. The system used a highly integrated and ultra-low power MSP430 single-chip micro-computer with an independent functional module. This allowed route planning software to direct the UAV to the desired spray area. The test results of route precision showed that in a 3–4 m/s crosswind, route deviations were around 0.2 m. The result of multiple-spraying swath uniformity tests showed a minimum coefficient of variation of 25% when flying at a height of 5 m with a spraying swath of 7 m and a wind speed of 0–2 m/s. When the spraying swath was 9 m or 5 m, the coefficients were 34% and 41%, respectively. Spray uniformity for these UAV tests were superior to the Standard Requirement for ultra-low volume spraying variation coefficient, 60%. [ABSTRACT FROM AUTHOR]

Various structures of a regulatory controller ensuring a bumpless switch from manual to automatic control are analyzed. Recommendations for the bumpless switch implementation are made for an automatic control system of steam boiler's feed water drum. [ABSTRACT FROM AUTHOR]

Practical applications of controllers often impose further requirements on the implementation beyond the actual control performance, such as the ability to switch between manual and automatic control or between different control laws or controller parameter settings, known as bumpless transfer. Another common requirement is to limit the control signal in magnitude and/or rate. This paper examines and extends several discrete-time variants of active disturbance rejection control (ADRC), which is increasingly being applied especially in the field of power electronics and drives, in this regard. Detailed guidelines for practical ADRC implementations with these abilities are presented, and all features are being demonstrated with the help of simulation examples. [ABSTRACT FROM PUBLISHER]

A system which ensures stabilization of filament velocity and tension has been developed to control the process of rewinding filaments. The main stage in the system's operation is the matching of the velocities with the prescribed tension and diameter of the package. A PID controller serves as the main control element for fine adjustment of the system. To optimize the parameters of the PID controller, the dynamic characteristics of the filament rewinding process were determined by experimentally identifying recorded data on transients and then approximating them with transfer functions. [ABSTRACT FROM AUTHOR]

Dynamic development of internal combustion engines creates a need to adopt a strategy concerning operational use of these driving units based on the knowledge of their technical condition. The assessment of technical condition belongs to tasks of technical diagnostics. This article presents an analysis of issues concerning vibration diagnostics of automatic compensators of clearances in piston valves of combustion engine. Scientific experiments focused on delivering information necessary to create (and also to validate) diagnostic models enabling assessment of technical condition of those elements of combustion engine that are essential taking into account effectiveness and durability that were carried out and described here. On the basis of the worked out diagnostic model, the algorithm for assessment of the technical condition of automatic compensators of valve clearance was created. [ABSTRACT FROM AUTHOR]

An Automated Demand Response is the most fundamental energy service that contributes to balancing the power demand with the supply, in which it realizes extensive interoperations between the power consumers and the suppliers. The OpenADR specification has been developed to facilitate the service communications, and several facilities offer primitive forms of services in a retail market. However, few researches have reported the details of such a real-world service yet, and thus we are still unaware of how it works exactly. Instead, we rely on our textbooks to design next generations of the ADR service. To overcome the discrepancy of our understanding, this paper shares our hand-on experiences on the commercialized ADR service. In particular, we deploy smart submeters to manage energy loads and install an energy management system in a small commercial facility, helping the owner participate in the ADR service that a local utility offers. The building owner makes a service contract with a qualified load aggregator based on her curtailment rate, a reference point that decides the success of her load curtailment. With the rate, the customer facility participates in three DR events for tests that last for 2, 1, and 3 hours, respectively. Our experimental results are illustrated with discussions on various aspects of the service. [ABSTRACT FROM AUTHOR]

SUMMARY A method for estimating the sway angle using an observer has already been proposed. The state observer estimates the sway angle accurately and must use the detected sway angle value. However, the estimated sway angle has an error owing to rope length error, friction force, and wind. Moreover, the container mass cannot be determined, and therefore the observer parameter is not suitable. We already proposed robust antisway control for overcoming rope length error without adding a new sensor. Further, we designed a friction disturbance observer to cancel out the influence of the friction force. In this paper, we first propose a container mass estimation method when a crane system performs rolling up control. The observer parameter can be selected using the estimated mass value. Second, in crane parallel shift control, we propose a robust antisway control even when there is a wind disturbance. We design a wind disturbance observer and propose a wind disturbance estimator to separate the friction observer output from the wind disturbance observer output. We confirm through experiments that the proposed method can reduce vibration. [ABSTRACT FROM AUTHOR]

Fast restoration of critical loads and non-black-start generators can significantly reduce the economic losses caused by power system blackouts. In a parallel power system restoration scenario, the sectionalization of restoration subsystems plays a very important role in determining the pickup of critical loads before synchronization. Most existing research mainly focuses on the startup of non-black-start generators. The restoration of critical loads, especially the loads with cold load characteristics, has not yet been addressed in optimizing the subsystem divisions. As a result, sectionalized restoration subsystems cannot achieve the best coordination between the pickup of loads and the ramping of generators. In order to generate sectionalizing strategies considering the pickup of critical loads in parallel power system restoration scenarios, an optimization model considering power system constraints, the characteristics of the cold load pickup and the features of generator startup is proposed in this paper. A bi-level programming approach is employed to solve the proposed sectionalizing model. In the upper level the optimal sectionalizing problem for the restoration subsystems is addressed, while in the lower level the objective is to minimize the outage durations of critical loads. The proposed sectionalizing model has been validated by the New-England 39-bus system and the IEEE 118-bus system. Further comparisons with some existing methods are carried out as well. [ABSTRACT FROM AUTHOR]