Automated Irrigation and Fertigation System Applying Sensing Technology

Internet of Things (IoT) is the most discussed topic nowadays and it finds many applications in various industries. The development of efficient agricultural systems has become essential to address the challenges of feeding the enormous and ever-increasing population around the globe. One way of dealing with this is to expand agricultural production standard and quantity. An integrated IoT system with irrigation and finishing on the market was missing. To increase production efficiency, farmers shall collect massive data from various devices. The system's effectiveness depends on the performance of the sensor under various climate changes. The network and a closed-loop feedback system need to be connected to the system for maximum operational capacity. The module of the Soil Moisture Sensor and the MCU ESP8266 V2 MCU Node, the float switch and the 5V Optocoupler relay module are used in this project. The remote control of the system is a mobile application. If the moisture level in the soil reaches the desired value, it will stop water supply. The project could be expended on a larger scale in the future and the system may also be developed with solar energy rather than batteries.

Number and Distribution of Fiducial Fibres in a Spectroscopic Survey Telescope

To date, the Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) has been in operation for 12 years. To improve the telescope’s astronomical observation accuracy, the original open-loop fibre positioning system of LAMOST is in urgent need of upgrading. The upgrade plan is to locate several fibre view cameras (FVCs) around primary mirror B to build a closed-loop feedback control system. The FVCs are ~20 m from the focal surface. To reduce a series of errors when the cameras detect the positions of the optical fibres, we designed fiducial fibres on the focal surface to be fiducial points for the cameras. Increasing the number of fiducial fibres can improve the detection accuracy of the FVC system, but it will also certainly reduce the number of fibre positioners that can be used for observation. Therefore, the focus of this paper is how to achieve the quantity and distribution that meet the requirements of system detection. In this paper, we introduce the necessity of using fiducial fibres, propose a method for selecting their number, and present several methods for assessing the uniformity of their distribution. Finally, we use particle swarm optimization to find the best distribution of fiducial fibres.

Experimental Comparison of PID Based RPM Control for Long Horizontal vs. Vertical Drillstring

Drilling vibrations has been identified as a key performance limiter that prevents successful energy transfer from the surface to the bit. The resultant irregular bit rotation speed causes drilling challenges like poor hole quality and reduction in rate of penetration to name a few. Amongst other vibration suppression techniques, active control of vibrations is widely used and recommended. Active control system utilizes a closed loop feedback control to continuously adapt to downhole vibrations detected at the surface. The system requires regular tuning and upgrades which is done experimentally before field deployment. The paper presents a PID based experimental tuning of horizontal and vertical strings for irregular RPM. In doing so, the paper highlights the need of having horizontal experimental setups for state-of-the-art PID tuning for downhole RPM. The settling time of irregular RPM for horizontal setup is found to be lower than the vertical configuration due to multiple contact points and increased friction coefficient.

Implementing an Anonymous Closed-Loop Feedback Process and Associations With ACGME Annual Survey Scores in a Family Medicine Residency

Background and Objectives: The annual Accreditation Council for Graduate Medical Education (ACGME) survey evaluates numerous variables, including resident satisfaction with the training program. We postulated that an anonymous system allowing residents to regularly express and discuss concerns would result in higher ACGME survey scores in areas pertaining to program satisfaction. Methods: One family medicine residency program implemented a process of quarterly anonymous closed-loop resident feedback and discussion in academic year 2012-2013. Data were tracked longitudinally from the 2011-2019 annual ACGME resident surveys, using academic year 2011-2012 as a baseline control. Results: For the survey item “Satisfied that evaluations of program are confidential,” years 2013-2014, 2014-2015, and 2018-2019 showed a significantly higher change from baseline. For “Satisfied that program uses evaluations to improve,” year 2018-2019 had a significantly higher percentage change from baseline. For “Satisfied with process to deal with problems and concerns,” year 2018-2019 showed significantly higher change. For “Residents can raise concerns without fear,” years 2013-2014 and 2018-2019 saw significantly higher changes. Conclusions: These results suggest that this feedback process is perceived by residents as both confidential and promoting a culture of safety in providing feedback. Smaller changes were seen in residents’ belief that the program uses evaluations to improve, and in satisfaction with the process to deal with problems and concerns.

Performance Analysis of Vibration Sensors for Closed-Loop Feedback Health Monitoring of Mechanical Equipment

In this paper, we analyze the performance of mechanical equipment through a closed-loop feedback health monitoring vibration sensor, develop an OTDR optical signal reception and the processing module, and realize the reception, amplification, and filtering of the backscattered optical signal. In terms of vibration signal demodulation, the FPGA signal processing module was developed and debugged to realize the intermodulation with OTDR optical signal reception processing module and the preprocessing of the vibration data stream by taking advantage of the FPGA in parallel high-speed data stream processing. The objective function is constructed based on the dynamic data of the first four vertical frequencies of the modal recognition and the static data of the constant-load cable force of the inclined cable, and the third-order response surface method is applied to fit the response surface function of each correction target. The errors between the corrected FEM calculated values and the measured results are within 5%. The results were compared with the results of static and dynamic corrections, and the results showed that the joint static and dynamic corrections using the third-order response surface could obtain a finite element model that was more comprehensive and closer to the actual engineering response. A 180° feedback gain is set in the mass detection system to reduce the system’s equivalent mass and increase the system resonant frequency. An inverse lock-in amplifier is used instead of a high-frequency bandpass filter to spectrally migrate the useful frequencies and better filter out noise interference. A thin-film microresonant pressure sensor, a cantilever beam microresonant gas sensor, and a microresonant biosensor were designed and developed using the micromachining process. A closed-loop feedback method was used to design a low-frequency detection system, a medium-frequency detection system, and a high-frequency feedback detection based on a phase-locked loop system, completed open-loop and closed-loop detection experiments of the intrinsic frequency of the sensor, through-pressure experiments of the pressure sensor, low and medium frequency gas-sensitive experiments of the gas sensor, and high-frequency detection experiments of the biosensor oxygen absorption/deoxygenation, and measured the mass of individual oxygen molecules.

A terrain treadmill to study small animal locomotion through large obstacles

A major challenge to understanding locomotion in complex 3-D terrain with large obstacles is to create tools for controlled, systematic lab experiments. Existing terrain arenas only allow observations at small spatiotemporal scales (~10 body length, ~10 stride cycles). Here, we create a terrain treadmill to enable high-resolution observations of small animal locomotion through large obstacles over large spatiotemporal scales. An animal moves through modular obstacles on an inner sphere, while a rigidly-attached, concentric, transparent outer sphere rotated with the opposite velocity via closed-loop feedback to keep the animal on top. During sustained locomotion, a discoid cockroach moved through pillar obstacles for 25 minutes (≈ 2500 strides) over 67 m (≈ 1500 body lengths), and was contained within a radius of 4 cm (0.9 body length) for 83% of the duration, even at speeds of up to 10 body length/s. The treadmill enabled observation of diverse locomotor behaviors and quantification of animal-obstacle interaction.