Unmanned Aerial Vehicles (UAVs) have recently rapidly grown to facilitate a wide range of innovative applications that can fundamentally change the way cyber-physical systems (CPSs) are designed. CPSs are a modern generation of systems with synergic cooperation between computational and physical potentials that can interact with humans through several new mechanisms. The main advantages of using UAVs in CPS application is their exceptional features, including their mobility, dynamism, effortless deployment, adaptive altitude, agility, adjustability, and effective appraisal of real-world functions anytime and anywhere. Furthermore, from the technology perspective, UAVs are predicted to be a vital element of the development of advanced CPSs. Therefore, in this survey, we aim to pinpoint the most fundamental and important design challenges of multi-UAV systems for CPS applications. We highlight key and versatile aspects that span the coverage and tracking of targets and infrastructure objects, energy-efficient navigation, and image analysis using machine learning for fine-grained CPS applications. Key prototypes and testbeds are also investigated to show how these practical technologies can facilitate CPS applications. We present and propose state-of-the-art algorithms to address design challenges with both quantitative and qualitative methods and map these challenges with important CPS applications to draw insightful conclusions on the challenges of each application. Finally, we summarize potential new directions and ideas that could shape future research in these areas. M 2 respectively. However, as shown in Fig.1, both technologies provide two extremes for surveillance with respect to accuracy versus intrusive deployment and maintenance. SRS provides slow large-scale monitoring, while CSNs require widespread deployment and constant human intervention for setup and maintenance, which may not be feasible particularly in harsh environments. On the one hand, SRS cannot be used for finegrain monitoring, such as monitoring of structural objects, with high accuracy, which limits its usage in many applications that require close monitoring and context detection [5]. On the other hand, traditional sensor networks (SNs) are spreading in countless number of Internet of Things (IoT) applications to provide automatic monitoring of objects, humans, and/or infrastructure. SNs, however, require permanent deployment of large magnitude of localized sensors, intrusively to the environment in many cases, and also require constant human intervention to manage and maintain. The proliferation of lowcost UAVs [6] is emerging to provide innovative ways of low altitude sensing with zero-deployment (i.e., no fixed deployment requirements) that can fundamentally change the way such applications are designed.Similar to surveillance applications, UAV technologies have progressed significantly in several applications in the past decade, making commercial and civil applications feasible and compelling. As it occurs with many disruptive technolo...

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These preliminary results suggest that laparoscopic-assisted sigmoidectomy can be used safely for the surgical treatment of diverticular disease.

A group of small spacecraft able to change their relative position and attitude through the use of the potential function method is discussed. The spacecraft shapes, sizes and manoeuvring capabilities are not identical, although all are assumed to manoeuvre using continuous thrusters. A hyperbolic form of the attractive potential function is used to reduce actuator effort by using natural orbital motion to approaching the goal configuration. A superquadric repulsive potential with 3D a rigid object representation is then used to provide an accurate representation of the shape of spacecraft in the potential function. As the spacecraft start away from their goal, a parabolic attractive potential is inefficient as the control force increases with distance from the goal. Using a hyperbolic attractive potential, the control force is independent of the distance to goal, ensuring smooth manoeuvring towards the goal with a bound actuator effort.

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Background: Laparoscopic cholecystectomy is the most commonly performed operation of the digestive tract. )It is considered as the gold standard treatment for cholelithiasis. Aim: To evaluate the outcome of it regarding length of hospital stay, complications, morbidity and mortality at a secondary hospital. Methods: Data of 492 patients who underwent laparoscopic cholecystectomy were retrospectively reviewed. Patients’ demographics, co-morbid diseases, previous abdominal surgery, conversion to open cholecystectomy, operative time, intra and postoperative complications, and hospital stay were collected and analyzed from patients’ files. Results: Out of 492 patients, 386 (78.5%) were females and 106 (21.5%) males. The mean age of the patients was 49.35±8.68 years. Mean operative time was 65.94±11.52 min. Twenty-four cases (4.9%) were converted to open surgery, four due to obscure anatomy (0.8%), 11 due to difficult dissection in Calot’s triangle (2.2%) and nine by bleeding (1.8%). Twelve (2.4%) cases had biliary leakage, seven (1.4%) due to partial tear in common bile duct, the other five due to slipped cystic duct stables. Mean hospital stay was 2.6±1.5 days. Twenty-one (4.3%) developed wound infection. Port site hernia was detected in nine (1.8%) patients. There was no cases of bowel injury or spilled gallstones. There was no mortality recorded in this series. Conclusions: Laparoscopic cholecystectomy is a safe and effective line for management of gallstone disease that can be performed with acceptable morbidity at a secondary hospital.