The Analysis of Transitions in Economic Performance Using Covariate Dependent Markov Model.

Tfte GDP or GNP as a measure of economic performance of a country changes continuously. We can identify the factors that precede its ups and downs

Contrasting ability of deep and shallow rooting rice genotypes to grow through plough pans containing simulated biopores and cracks

Fundings: Commonwealth Scholarship Commission Open access via Springer agreement Acknowledgements This study was funded by the Commonwealth Scholarship Commission in the UK. We thank all people that contributed to this work. In particular, Luke Harrold, Rong Qu, Yehia Hazzazi, Licida Maria Giuliani and Istiaq Ahmed with their stimulating discussion during and after setting experiment. We are highly grateful to Annette Rafan, Dr. Stewart J Chalmers and Jaime Buckingham for providing technical supportPeer reviewedPublisher PD

Rhizosphere development under alternate wetting and drying in puddled paddy rice

We thank all people who contributed to this work. In particular, Annette Raffan, Luke Harrold, Faraj Elsakloul, Utibe Utin and Yehia Hazzazi for their vivid discussion during and after setting experiment. We would also like to thank Dr. Stewart J Chalmers and Jaime Buckingham for providing technical support. We especially thank Dr. Craig Sturrock, Hounsfield Facility, University of Nottingham for supporting X-ray CT image analysis.Peer reviewe

Design and Evaluation of Sensor Housing for Boundary Layer Profiling Using Multirotors

Traditional configurations for mounting Temperature–Humidity (TH) sensors on multirotor Unmanned Aerial Systems (UASs) often suffer from insufficient radiation shielding, exposure to mixed and turbulent air from propellers, and inconsistent aspiration while situated in the wake of the UAS. Descent profiles using traditional methods are unreliable (when compared to an ascent profile) due to the turbulent mixing of air by the UAS while descending into that flow field. Consequently, atmospheric boundary layer profiles that rely on such configurations are bias-prone and unreliable in certain flight patterns (such as descent). This article describes and evaluates a novel sensor housing designed to shield airborne sensors from artificial heat sources and artificial wet-bulbing while pulling air from outside the rotor wash influence. The housing is mounted above the propellers to exploit the rotor-induced pressure deficits that passively induce a high-speed laminar airflow to aspirate the sensor consistently. Our design is modular, accommodates a variety of other sensors, and would be compatible with a wide range of commercially available multirotors. Extensive flight tests conducted at altitudes up to 500m Above Ground Level (AGL) show that the housing facilitates reliable measurements of the boundary layer phenomena and is invariant in orientation to the ambient wind, even at high vertical/horizontal speeds (up to 5m/s) for the UAS. A low standard deviation of errors shows a good agreement between the ascent and descent profiles and proves our unique design is reliable for various UAS missions

Design and Evaluation of Sensor Housing for Boundary Layer Profiling Using Multirotors

Traditional configurations for mounting Temperature–Humidity (TH) sensors on multirotor Unmanned Aerial Systems (UASs) often suffer from insufficient radiation shielding, exposure to mixed and turbulent air from propellers, and inconsistent aspiration while situated in the wake of the UAS. Descent profiles using traditional methods are unreliable (when compared to an ascent profile) due to the turbulent mixing of air by the UAS while descending into that flow field. Consequently, atmospheric boundary layer profiles that rely on such configurations are bias-prone and unreliable in certain flight patterns (such as descent). This article describes and evaluates a novel sensor housing designed to shield airborne sensors from artificial heat sources and artificial wet-bulbing while pulling air from outside the rotor wash influence. The housing is mounted above the propellers to exploit the rotor-induced pressure deficits that passively induce a high-speed laminar airflow to aspirate the sensor consistently. Our design is modular, accommodates a variety of other sensors, and would be compatible with a wide range of commercially available multirotors. Extensive flight tests conducted at altitudes up to 500m Above Ground Level (AGL) show that the housing facilitates reliable measurements of the boundary layer phenomena and is invariant in orientation to the ambient wind, even at high vertical/horizontal speeds (up to 5m/s) for the UAS. A low standard deviation of errors shows a good agreement between the ascent and descent profiles and proves our unique design is reliable for various UAS missions

Three-Phase Induction Motor Speed Estimation Using Recurrent Neural Network

In induction motor speed control method, the development of the field-oriented control (FOC) algorithm which can control torque and flux separately enables the motor to replace many roles of DC motors. Induction motor speed control can be done by using a close loop system which requires a speed sensor. Referring to the speed sensor weaknesses such as less accurate of the measurement, this is due to the placement of the sensor system that is too far from the control system. Therefore, a speed sensorless method was developed which has various advantages. In this study, the speed sensorless method using an artificial neural network with recurrent neural network (RNN) as speed observer on three-phase induction motor has been discussed. The RNN can maintain steady-state conditions against a well-defined set point speed, so that the observer is able and will be suitable if applied as input control for the motor drives. In this work, the RNN has successfully estimated the rotor flux of the induction motor in MATLAB R2019a simulation as about 0.0004Wb. As based on speed estimation error, the estimator used has produced at about 26.77%, 8.7% and 6.1% for 150rad/s, 200rad/s and 250rad/s respectively. The future work can be developed and improved by creating a prototype system of the induction motor to get more accurate results in real-time of the proposed RNN observer

Extending Shelf Life of Guava Fruits by Mint oil and UVC Treatments

A lot of quarantine methods have been developed to replace fumigants in the control of arthropods and microorganisms in post–harvest management of fruits and vegetables. That is, guava fruit is infested in Sudan by a number of hexapods which include Ceratitis capitata Weid., Ceratitis quinaria (Bez.), Certatitis cosyra WLK., Bactrocera invadens Drew, Trusta & White and Bactrocera zonata (Saunders).This study aims at using some uncommonly used treatments in improving the storability of guava fruits in Sudan. That is, UVC (ultraviolet rays type C) and coating with mint oil were used to disinfest guava from fruit flies at ambient temperature. The results, after 9 days bench storage, showed an infestation percentage of 20, 33 and 38% for mint, UVC and the control, respectively. The corresponding data for the range of infestation were 18, 20 and 48 and for the mean number of insects in infested fruits were 8.3, 8.8 and 15.2. The quality indexes studied reflected 9.5, 20.5 and 22.6% weight loss, for the mint oil, UVC and the control lots, respectively. The corresponding data for marketable retention (%) were 100, 10 and 13; the fruit firmness, 1.6, 0.3, and 0.1; acidity (%), 0.2 for all; ascorbic acid (mg/ 100 g pulp), 196, 190, and 194; reducing sugar (g/ 100g), 8.2, 7.6, and 7.6; sensory quality includes appearance (%), 84, 42, and 30; taste (%), 79, 41, and 34; flavor (%), 88, 42, and 40, respectively. These results revealed the edge of mint oil coating over UVC and the untreated lots