Biology-Inspired Adaptive and Nonlinear Robust Control of BAUV Using Pectoral-Like Fins

Aquatic animals have splendid ability to move smoothly through water using variety of oscillating fins. Presently researchers are involved in developing biorobotic autonomous underwater vehicles (BAUVs) which have the ability to swim like marine animals. Multiple oscillating fins (dorsal, caudal, pectoral, pelvic, etc.) can be mounted on BAUVs to generate control forces for propulsion and maneuvering. In this research work, control of the BAUVs using pectoral fins alone is considered. The oscillating pectoral fins produce unsteady periodic forces. The control of motion of an BAUV in yaw and dive planes are considered

Optimizing Fuel-Constrained UAV-UGV Routes for Large Scale Coverage: Bilevel Planning in Heterogeneous Multi-Agent Systems

Fast moving unmanned aerial vehicles (UAVs) are well suited for aerial surveillance, but are limited by their battery capacity. To increase their endurance UAVs can be refueled on slow moving unmanned ground vehicles (UGVs). The cooperative routing of UAV-UGV multi-agent system to survey vast regions within their speed and fuel constraints is a computationally challenging problem, but can be simplified with heuristics. Here we present multiple heuristics to enable feasible and sufficiently optimal solutions to the problem. Using the UAV fuel limits and the minimum set cover algorithm, the UGV refueling stops are determined. These refueling stops enable the allocation of mission points to the UAV and UGV. A standard traveling salesman formulation and a vehicle routing formulation with time windows, dropped visits, and capacity constraints is used to solve for the UGV and UAV route, respectively. Experimental validation on a small-scale testbed (http://tiny.cc/8or8vz) underscores the effectiveness of our multi-agent approach.Comment: The paper is submitted to MRS 202

A case of carpal tunnel syndrome in patient with rheumatoid arthritis

Department of Internal Medicine Rheumatology and Nephrology, Nicolae Testemitanu State University of Medicine and Pharmacy, Chisinau, Republic of Moldova, The 8th International Medical Congress for Students and Young Doctors, September 24-26, 2020Background. Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy caused by compression of the median nerve at the wrist, and most likely the most common peripheral neurological involvement in patients with rheumatoid arthritis. It is manifested withpain and/either paresthisias at night associated with weakness, loss of dexterity and even thenar atrophy. Case report. We report a case of a female patient GN, 42y.o., with established seropositive (FR-153 IU/L; anti-CCP – 340 U/ml), highly active (DAS28-5.47) Rheumatoid Arthritis. Now she presented with inflammatory joint pain and swelling in 11 joints (including elbow bilaterally, wrist bilaterally, metacarpophalangeal, and proximal interphalangeal joints), morning stiffness is more than2 hours, additionally she reports numbness, tingling and burning in the 1,2 and 3rd fingers of the left hand. Carpal tunnel syndrome was suspected. Both Tinel’s (paresthesia in a median nerve distribution, after percussion of the median nerve at the wrist) and Phalen’s (paresthesia in a median nerve distribution, after passive flexion of the hand at the wrist) signs were positive. The patient recalls having similar symptoms in the right hand 3 years ago. An EMG exam performed at that time was showing: Prolongation of the median motor distal latency and median F-wave abnormalities. A diagnosis of carpal tunnel syndrome was established the patient being treated with surgical approach by neurolysis of the median nerve. Considering thatthe patient presented with swelling in the left wrist joint, it was decided to do an infiltration of corticosteroids. The patient had a satisfactory recovery with resolution of all carpal tunnel symptoms within 1 week. When looking for a detailed history of disease itwas concluded that the carpal tunnel syndrome in the right hand occurred most likely also as a consequence of joint swelling which is frequently disregarded as an important and easily treatable cause of carpal tunnel syndrome. However, the situation was less clear due to the fact that it occurred at the onset of rheumatoid arthritis. Conclusions. Carpal tunnel syndrome is the most frequent nerve entrapment condition associated with RA. Although diagnosis is at time tricky, one shouldn’t prompt surgical approach since most cases are caused by flexor tenosynovitis which responds well to injections with corticosteroids. However to prevent development of such complication, effective disease modifying therapy should be in place

Assessing avionics-based GNSS integrity augmentation performance in UAS mission- and safety-critical tasks

The integration of Global Navigation Satellite System (GNSS) integrity augmentation functionalities in Unmanned Aerial Systems (UAS) has the potential to provide an integrity-augmented Sense-and-Avoid (SAA) solution suitable for cooperative and non-cooperative scenarios. In this paper, we evaluate the opportunities offered by this integration, proposing a novel approach that maximizes the synergies between Avionics Based Integrity Augmentation (ABIA) and UAS cooperative/non-cooperative SAA architectures. When the specified collision risk thresholds are exceeded, an avoidance manoeuvre is performed by implementing a heading-based differential geometry or pseudospectral optimization to generate a set of optimal trajectory solutions free of mid-air conflicts. The optimal trajectory is selected using a cost function with minimum time constraints and fuel penalty criteria weighted for separation distance. The optimal avoidance trajectory also considers the constraints imposed by the ABIA in terms of UAS platform dynamics and GNSS satellite elevation angles (plus jamming avoidance when applicable), thus preventing degradation or loss of navigation data during the Track, Decision and Avoidance (TDA) process. The performance of this Integrity-Augmented SAA (IAS) architecture was evaluated by simulation case studies involving cooperative and non-cooperative platforms. Simulation results demonstrate that the proposed IAS architecture is capable of performing high-integrity conflict detection and resolution when GNSS is used as the primary source of navigation data

Avionics-based GNSS integrity augmentation performance in a jamming environment

Intentional and unintentional radiofrequency interference (i.e., jamming) can result in degraded navigation accuracy or complete loss of the GNSS signal tracking. Jammers can be classified into three broad categories: Narrowband Jammers (NBJ), Spread Spectrum Jammers(SSJ) and Wideband Gaussian Jammers (WGJ). In recent years, a number of effective jamming detection and anti-jamming (filtering and suppression) techniques have been developed for military GNSS applications and some of them are envisaged to be used for civil purposes (e.g., terrorist attacks). The synergies between these jamming detection techniques and our newly developed Avionics-Based Integrity Augmentation (ABIA) system are investigated in this paper. In particular, GNSS vulnerability to NBJ, SSJ and WGJ types of jamming is analytically described in terms of Jamming to Signal (J/S) tracking thresholds and the models for calculating the minimum acceptable aircraft-to-jammer ranges are presented. Simulation results demonstrate that the proposed ABIA architecture is capable of performing jamming detection and avoidance when GNSS is considered as the primary source of navigation data

Evaluating GNSS integrity augmentation techniques for UAS sense-and-avoid

Global Navigation Satellite Systems (GNSS) far exceed the navigation accuracies provided by other state-of-the-art sensors for aerospace applications. This can support the development of low-cost and high performance navigation and guidance architectures for Unmanned Aircraft Systems (UAS) and, in conjunction with suitable data link technologies, the provision of Automated Dependent Surveillance (ADS) functionalities for cooperative Sense-and-Avoid (SAA). In non-cooperative SAA, the adoption of GNSS can also provide the key positioning and, in some cases, attitude data (using multiple antennas) required for automated collision avoidance. A key limitation of GNSS for both cooperative (ADS) and non-cooperative applications is represented by the achievable levels of integrity. Therefore, an Avionics Based Integrity Augmentation (ABIA) solution is proposed to support the development of an integrity-augmented SAA architecture suitable for both cooperative and non-cooperative scenarios. The performance of this Integrity-Augmented SAA (IAS) architecture was evaluated in representative simulation case studies. Additionally, the ABIA performances in terms of False Alarm Rate (FAR) and Detection Probability (DP) were assessed and compared with Space-Based and Ground-Based Augmentation Systems (SBAS/GBAS). Simulation results show that the proposed IAS architecture is capable of performing high-integrity conflict detection and resolution when GNSS is used as the primary source of navigation data and there is a synergy with SBAS/GBAS in providing suitable (predictive and reactive) integrity flags in all flight phases. Therefore, the integration of ABIA with SBAS/GBAS is a clear opportunity for future research towards the development of a Space-Ground-Avionics Augmentation Network (SGAAN) for UAS SAA and other safety-critical aviation applications

Physicochemical Approaches for Thin Film Energy Storage Devices through PVD Techniques

For the fabrication of thin films, Physical Vapor Deposition (PVD) techniques specified greater contribution than all other deposition techniques. Laser Ablation or Pulsed Laser deposition (PLD) technique is the one of most promising techniques for the fabrication of thin films among all other physical vapor deposition. In particular, flexible thin-film energy storage fabrication PLD plays an important role due to its special parameters such as fine thickness control, partial pressure atmospheric condition, pulsed repetition rate, in-situ annealing and microstructure optimization. Very recently, thin film supercapbatteries have been broadly studied, in which the battery and supercapacitor based electrodes are combined to obtain a high specific power and specific energy density and extended cycle stability. In order to fabricate thin film supercapbatteries, electrodes that have a large potential window, high capacitance, and capacity performance are vastly desired. Thus, the presented chapter represents an important enhancement in the growth of economical and eco-friendly thin flexible supercapbatteries and confirms their potential in sensible applications such as transport electronics devices and other gadgets

Design of Barrage Style Tidal Water Power Plant Structure to Reduce Sediment Accretions in Approach Channel, Entrance, Harbour and Backwaters of Cannanore Port, Kerala

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

TOXICITY OF ATRAZINE AND RELATED TO TESTICULAR, TISSUE DAMAGING ENZYME LEVELS IN POECILIA SPHENOPS

Objective: This study was designed to evaluate the toxic effects of Atrazine (ATZ) on the enzyme levels in Poecilia sphenops.Methods: The cytosolic testicular enzyme and tissue-damaging enzyme activity were measured in Poecilia sphenops was exposed to 3 sub-lethal concentrations (1.25, 2.5 and 5 mg/l) of atrazine for 100days and control was also maintained. The toxic effects of ATZ to Poecilia sphenops were assessed through testicular marker enzyme, tissue-damaging enzyme level.Results: The activities of testicular functional enzyme ALP, ACP, SDH, LDH, G6PDH and tissue-damaging the activities of glutamate oxaloacetic transaminase (GOT) and glutamate pyruvic transaminase (GPT) activity levels were altered in treated groups compared with that of the control.Conclusion: This study demonstrates that atrazine induces tissue damage in terms of enhanced enzyme activity and testicular enzyme activity in Poecilia sphenops. Atrazine has toxicity to the reproductive system in Poecilia sphenops