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The purpose of this study is to provide the full-state mathematical model and devise a nonlinear controller for a balloon-supported unmanned aerial vehicle (BUAV).

Newtonian mechanics is used to establish the nonlinear mathematical model of the proposed vehicle assembly which incorporates the dynamics of both balloon and quadrotor UAV. A controllable form of the nine degrees of freedom model is derived. Backstepping control is designed for the proposed model and simulations are performed to assess the tracking performance of the proposed control.

The results show that the proposed methodology works well for smooth trajectories in presence of wind gusts. Moreover, the final mathematical model is affine and various nonlinear control techniques can be used in the future for improved system performance.

Multi-rotor unmanned aerial vehicles (MUAVs) are equipped with controllers but are constrained by smaller flight endurance and payload carrying capability. On the contrary, lighter than air (LTA) aerial vehicles have longer flight times but have poor control performance for outdoor operations. One of the solutions to achieve better flight endurance and payload carrying capability is to augment the LTA balloon to MUAV. The novelty of this research lies in full-order mathematical modeling along with transformation to controllable form for the BUAV assembly.

This paper aims to compare the costs of deploying different wireless terrestrial broadband technologies in the Andes and Amazon Regions of Peru. These areas are representatives of different and challenging geographic regions throughout the globe that currently are severely underserved or unserved for vital broadband services necessary to bridge the “Digital Divide”.

The broadband technologies studied include Wi-Fi, Worldwide Interoperability for Microwave Access (WiMAX), long term evolution (LTE), TVWS and new stratospheric platforms (super-pressure balloons). This study conducts a technical analysis (design and simulation) of wireless broadband networks, and a bottom-up engineering cost analysis to estimate and compare the deployment and operating costs of the networks over a 10-year period. The analysis also identifies potential regulatory barriers to deployment associated with spectrum allocation licenses and overbooking requirements intended to improve quality of service.

Comparison of the capital and operating expenses of these options over a 10-year period finds that LTE and Wi-Fi can be the lowest cost alternatives, though significantly, stratospheric balloons have the lowest initial costs for the first few years and can factor as a low-cost broadband catalyst early in deployment. Finally, the lowest cost technology broadband roadmap for the 10-year period is presented, which includes using stratospheric balloons (carrying micro-LTE base stations) for the first years and deploying complementary terrestrial LTE networks for the rest of the 10-year period.

This study presents detailed technical and engineering cost analysis results of wireless access network deployments, including advanced wireless technologies and new unmanned aerial systems, to expand broadband services to rural areas in mountainous (Andes Region) and rainforest (Amazon Region) geographies to reduce the digital divide in emerging countries. Results aim to aid governments, regulators, internet service providers (incumbents and competitive) and content providers to assess current alternatives to expand broadband service in these rural areas.

Ring spinning is the most widely used spinning method at present. In the spinning, ring and traveller are the two important components of the twisting process. The properties of ring and traveller have a direct relationship with the yarn qualities and spinning speed. Therefore, the purpose of this paper is to study the mutual relationships of flange ring and traveller system by taking the 6802-type traveller with rectangular structure, BU-type traveller with toxoplasma structure and 772-type traveller with corrugated structure as examples.

First, the theoretical calculation models of force and inclinations of the traveller are given, and calculation methods of corresponding key parameters referred in the models are presented. Then, by using SolidWorks software, models of the three kinds of traveller straddling on the PG1-4254 type ring are built, and the traveller and ring are simulated by using ADAMS software. By using MATLAB software, the force and inclinations of the traveller during the rotation around ring are simulated. Finally, the spinning experiments are made.

It is shown that the abrasion of 6802-type traveller is the most serious, and corresponding yarn evenness and hairiness is the worst. The abrasion of BU-type traveller is the slightest, and corresponding yarn evenness is the best. The yarn spins by using 772-type traveller has the least hairiness.

In the paper, the mutual relationships of flange ring and traveller system have been studied. For giving analysis of force and inclinations of the traveller, calculation methods of the key common parameters are presented. By using SolidWorks software, the physical models of the three kinds of traveller straddling on the PG1-4254 type ring are built. And then, the force and inclinations of the traveller during the rotation around ring are simulated by using MATLAB software. At last, the spinning experiments are made to analyse the simulation results.

The purpose of this study is to determine the impact of two-phase power law nanofluid on a curved arterial blood flow under the presence of ovelapped stenosis. Over the past couple of decades, the percentage of deaths associated with blood vessel diseases has risen sharply to nearly one third of all fatalities. For vascular disease to be stopped in its tracks, it is essential to understand the vascular geometry and blood flow within the artery. In recent scenarios, because of higher thermal properties and the ability to move across stenosis and tumor cells, nanoparticles are becoming a more common and effective approach in treating cardiovascular diseases and cancer cells.

The present mathematical study investigates the blood flow behavior in the overlapped stenosed curved artery with cylinder shape catheter. The induced magnetic field and entropy generation for blood flow in the presence of a heat source, magnetic field and nanoparticle (Fe₃O₄) have been analyzed numerically. Blood is considered in artery as two-phases: core and plasma region. Power-law fluid has been considered for core region fluid, whereas Newtonian fluid is considered in the plasma region. Strongly implicit Stone’s method has been considered to solve the system of nonlinear partial differential equations (PDE’s) with 10–6 tolerance error.

The influence of various parameters has been discussed graphically. This study concludes that arterial curvature increases the probability of atherosclerosis deposition, while using an external heating source flow temperature and entropy production. In addition, if the thermal treatment procedure is carried out inside a magnetic field, it will aid in controlling blood flow velocity.

The findings of this computational analysis hold great significance for clinical researchers and biologists, as they offer the ability to anticipate the occurrence of endothelial cell injury and plaque accumulation in curved arteries with specific wall shear stress patterns. Consequently, these insights may contribute to the potential alleviation of the severity of these illnesses. Furthermore, the application of nanoparticles and external heat sources in the discipline of blood circulation has potential in the medically healing of illness conditions such as stenosis, cancer cells and muscular discomfort through the usage of beneficial effects.

We develop a Bayesian approach for modeling brain activation and connectivity from functional magnetic resonance image (fMRI) data. Our approach simultaneously estimates local hemodynamic response functions (HRFs) and activation parameters, as well as global effective and functional connectivity parameters. Existing methods assume identical HRFs across brain regions, which may lead to erroneous conclusions in inferring activation and connectivity patterns. Our approach addresses this limitation by estimating region-specific HRFs. Additionally, it enables neuroscientists to compare effective connectivity networks for different experimental conditions. Furthermore, the use of spike and slab priors on the connectivity parameters allows us to directly select significant effective connectivities in a given network.

We include a simulation study that demonstrates that, compared to the standard generalized linear model (GLM) approach, our model generally has higher power and lower type I error and bias than the GLM approach, and it also has the ability to capture condition-specific connectivities. We applied our approach to a dataset from a stroke study and found different effective connectivity patterns for task and rest conditions in certain brain regions of interest (ROIs).

The aim of this study, the moderating effect of pleasure-seeking and loss aversion, was investigated in relation to the big five personality traits with regard to risky investment intentions.

In the study, the data was obtained between January and November 2019 via an online survey with convenience sampling. The total number of subjects is 886. The authors used IBM SPSS Statistics for analysis. Exploratory factor analysis, correlation analysis, regression analysis and discriminant analysis were performed.

Significant relationships were found between five personality traits and risky investment intentions. In these relationships, the moderator effect of pleasure-seeking for extraversion, conscientiousness and neuroticism personality traits was also determined. Besides, investment preferences for choosing “unknown and new investment” against “known and experienced investment”, which is a typical feature of the balloon periods, were modeled with big five personality traits and motivation variables (pleasure-seeking and loss aversion) and the equation was formed. As a result, high accuracy classification success was obtained.

The study is unique owing to its findings. In addition, general risk aversion and risky investment intention were investigated simultaneously to explain the different findings in the literature regarding the attitude of big five personality traits to risk and personality traits that show consistent approach were identified.

THE Advisory Committee for Aeronautics was appointed on April 30, 1909. The twenty‐one years since that date contain nearly the whole history of flight by men. To quote from Sir Walter Raleigh, “At the beginning of the year 1909 the mystery and craft of flying was still known only to the few. In the two years which followed, it was divulged to the many, and became a public spectacle.” In the previous year, in France, Henri Farman, Delagrange, and Blériot had flown their various machines. For some years previously, the Wrights had been at work in America, and in 1903 had flown in a power‐driven machine. In August, 1908, Wilbur Wright had shown, in France, what might be achieved by the application of scientific investigation and research to the art of flying, and had caused Delagrange, who witnessed his manoeuvres in the air at the Hunandières race‐course, to exclaim, “Eh bien. Nous n'existons pas, nous sommes battus.”

The purpose of this paper is to describe a work that aims to solve contour detection problem using a planar deformable model and a swarm‐based optimization technique. Contour detection is an important task in image processing as it allows depicting boundaries of objects in an image. The proposed approach uses snakes as active contour model and adapts predator prey optimization (PPO) metaheuristic so that to define a new dynamic for evolving snakes in a way to reduce time complexity while providing good quality results.

In the proposed approach, contour detection has been cast as an optimization problem requiring function minimization. PPO has been used to develop a search strategy to handle the optimization process. PPO is a population‐based method inspired by the phenomenon of predators attack and preys evasion. It has been proposed as an improvement of particle swarm optimization (PSO) where additional particles are introduced to repel the other particles into the swarm. The introduced dynamic is intended to achieve better exploration of the search space. In the design, a representation scheme has been first defined. Each particle either a predator or a prey is represented as a curve (snake) defined by a set of control points. The idea is then to evolve a set of curves using the dynamic governed by PPO model equations. As a result, the curve that optimizes a defined energy function is identified as the contour of the target object.

Application of the proposed method to a variety of images using a multi agent platform has shown that good quality results have been obtained compared to a PSO‐based method.

Nature inspired computing is an emergent paradigm that witnesses a growing interest because it suggests a new philosophy to optimization. This work contributes in showing its suitability to solve problems even it is still at infancy. In another hand, despite the amount of work done in image processing, it is still required to define new methods for image segmentation. This work outlines a new way to deal with this problem through the use of PPO.

The purpose of the paper is to reflect on how sensegiving cues are encapsulated in models of reporting for human resources. This has been by investigating elements, arguments and formats of the models.

This paper focuses on the three discourses of human resource reporting that Jan‐Erik Gröjer is a part of. This paper is an appreciation of the importance of Jan‐Erik's work in the field of human resource communication as well as an illustration of how ideas and models changes over time.

The paper concludes that: there is no coherent idea of how sensegiving should be made in order to affect the sensemaking processes of human resources, the models emanate from different forms of critiques and the sensegiving cues change accordingly, and accounting for human resources has an ethical dimension.

The choice of model for reporting on human resources affects not only the content of the human resource report (the what and how question), but also affected by which arguments are considered as most efficient in the sensegiving process..

The paper contributes to the understanding of how sensemaking is dependent on which sensegiving cues bring forward in the accounts of human accounts.

Explores the life of Paul A. Samuelson, of whom it is said, that he is the ‘last generalist in economics’, from his early days in the USA. Gives great detail from his lecture, particularly for his provision of a rich, unknown source of new problems in economic science.