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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.

Drawings of some of the Constructional Features of the Flying Boat Described on the Opposite Page

This paper aims to present numerical simulations for a series of flight processes for the postlaunching stage of the “balloon-borne UAV system.” It includes the balloon further ascent motion after airborne launching. In terms of unmanned aerial vehicles (UAVs), the tailspin state and the charge-out process with an anti-tailspin parachute-assisted suspending are analyzed. Then, the authors conduct trajectory optimization simulations for the long-distance gliding process.

The balloon kinematics model and the parachute Kane multibody dynamic model are established. Using steady-state tailspin to reduced-order analysis and achieving change-out simulation by parachute suspension dynamic model. A reentry optimization control problem is developed and the Radau pseudo-spectral method is used to calculate the glide trajectory.

The established dynamic model and trajectory optimization method can effectively simulate the motion process of balloons and UAVs. The system mass reduction for launching UAVs will not cause damage to the balloon structure. The anti-tailspin parachute can reduce the UAV attack angles effectively. The UAV can glide to the designated target position by adjusting the attack angle and sideslip angle. The farthest flight distance after launching from 20 km height is 94 km and the gliding time is 40 min, which demonstrates the potential application advantage of high-altitude launching.

The research content and related conclusions of this article achieve a closed-loop analysis of the flight mission chain for the “balloon-borne UAV system,” which provides simulation references for relevant balloon launching experiments.

This paper establishes a complete set of numerical simulation models and can effectively analyze various postlaunching behaviors.

In recent years, high‐altitude/long‐endurance airship platforms have generated great interest as a means to provide communications and surveillance capabilities. The purpose of this paper is to develop a model for airship conceptual design and help provide insight into the viability of high‐altitude/long‐endurance airships.

A configuration analysis model with the consideration of pressure difference, temperature difference, and helium purity, etc. was developed. The influences of the airship payload, size and area required of solar cell with environment and operation parameters, such as operation latitude, pressure difference, temperature difference, helium purity, seasons, latitude, and wind speed, etc. were analyzed.

The results show that the area of solar cell required for stratospheric airship is very large under the condition of low altitude, high latitude, wind, and in winter, etc. which might make the design of high‐altitude/long‐endurance airship an elusive goal. They also show that the solar cell efficiency is the key technology in the control of solar cell area required for airships, and the technology advances in regenerative fuel cells and propeller efficiency have significant effects among on the airship payload, size, and solar cell area required for airship.

The paper analyses the energy balance of the high‐altitude/long‐endurance airship.

This paper aims to discuss the complexity of predicting the future and of making tourism futuristic predictions. It argues that tourism cannot be separated from the world context in which it operates and explores the various impacts of tourism on people and planet both in a near and more distant future.

This paper revises several reports and research by world economic and tourism authorities as they provide arguments for the study of trends and the complexity of the evolution of the travel and tourism industry.

There is no certain way to know what the future will bring to the tourism industry or how it will interact with society and the physical environment. What the author does know is that from the beginning of time, events do not occur in isolation and that travel and tourism will impact everything that it touches. It is impossible to make exact predictions as to what tourism will be like in the near and distant future, what the author does know is that humans will want to travel, to explore and to learn, and this desire will interact not only with tourism but with the course of history.

By exploring the evolution of tourism in the context of science, the author cannot even be certain where tourism will occur, if only on the same planet, within the other planets of the solar system or in the vastness of space. Science fiction predicts the latter, but only the unfolding of history will teach of the accuracy of future predictions and how the future of travel will be.

MATRA'S space activities employs, 1,350 people. Sales reach 1.7 billion francs, including 80% for export.

With more than 3.6 million overnights in 2012, Ötztal is the strongest destination in Tyrol, Austria. The destination encompasses very different geographic conditions suitable for different kinds of tourism offers. This results in a very strong winter season in the higher regions and a more seasonally balanced set of tourism offers in the lower regions. Until 2006 the destination was split into five parts, managed by five independent DMOs. After merging these DMOs, the destination management faced issues around how to integrate distinct stakeholder interests regarding tourism development. The case highlights how different actors are integrated into destination governance. One focus is on the destination network and relationships between different actors, while information exchange between different actor categories and influences on decisionmaking are also emphasized.

The purpose of this paper is to improve the control precision of the station-keeping control for a stratosphere airship through the feedforward-feedback PID controller which is designed by the wind speed prediction based on the incremental extreme learning machine (I-ELM).

First of all, the online prediction of wind speed is implemented by the I-ELM with rolling time. Second, the feedforward-feedback PID controller is designed through the position information of the airship and the predicted wind speed. In the end, the one-dimensional dynamic model of the stratosphere airship is built, and the controller is applied in the numerical simulation.

Based on the conducted numerical simulations, some valuable conclusions are obtained. First, through the comparison between the predicted value and true value of the wind speed, the wind speed prediction based on I-ELM is very accurate. Second, the feedforward-feedback PID controller designed in this paper is very effective.

This paper is very valuable to the research of a high-accuracy station-keeping control of stratosphere airship.