28 research outputs found
Maritime Networks, Port Efficiency, and Hinterland Connectivity in the Mediterranean
International audience; For millennia, the Mediterranean has been one of the most active trading areas, supported by a transport network connecting riparian cities and beyond to their hinterland. The Mediterranean has complex trade patterns and routes--but with key differences from the past. It is no longer an isolated world economy: it is both a trading area and a transit area linking Europe and North Africa with the rest of the world through the hub-and-spoke structure of maritime networks. Understanding how trade connectivity works in the Mediterranean, and elsewhere, is important to policy makers, especially those in developing countries in the Mediterranean, concerned with the economic benefits of large investment in infrastructure. Better connectivity is expected to increase trade with distant markets and stimulate activities in the hinterland. This book is a practical exploration of the three interdependent dimensions of trade connectivity: maritime networks, port efficiency, and hinterland connectivity. Because of the complexity and richness of maritime and trade patterns in the Mediterranean, the research book combines both a regional focus and globally scalable lessons. This book is intended for a wide readership of policy makers in maritime affairs, trade, or industry; professionals from the world of finance or development institutions; and academics. It combines empirical analysis of microeconomic shipping and port data with three case studies of choice of port (focusing on Spain, Egypt, and Morocco) and five case studies on hinterland development (Barcelona; Malta; Marseilles; Port Said East, Egypt; and Tanger Med, Morocco).
Document type: Boo
Connecting to Compete 2018: Trade Logistics in the Global Economy. The Logistics Perfomance Index and Its Indicators
The air connectivity index : measuring integration in the global air transport network
The authors construct a new measure of connectivity in the global air transport network, covering 211 countries and territories for the year 2007. It is grounded in network analysis methods, and is based on a gravity-like model that is familiar from the international trade and regional science literatures. It is a global measure of connectivity, in the sense that it captures the full range of interactions among all network nodes, even when there is no direct flight connection between them. The best connected countries are the United States, Canada, and Germany; the United States' score is more than two-thirds higher than the next placed country's, and connectivity overall follows a power law distribution that is fully consistent with the hub-and-spoke nature of the global air transport network. The measure of connectivity is closely correlated with important economic variables, such as the degree of liberalization of air transport markets, and the extent of participation in international production networks. It provides a strong basis for future research in areas such as air and maritime transport, as well as international trade.
Document type: Boo
The Cost of Being Landlocked: Logistics Costs and Supply Chain Reliability
The Cost of Being Landlocked\u27 proposes a new analytical framework to interpret and model the constraints faced by logistics chains on international trade corridors. The plight of landlocked developing countries (LLDCs) has naturally received special attention for decades, leading to a specific set of development priorities based upon the concept of dependence on the transit state. Therefore, the standard approach used to tackle the cost of being landlocked has been predominantly aimed at developing regional transport infrastructure and ensuring freedom of transit through regional conventions. But without sufficient attention given to the performance of logistics service delivery to traders, the standard approach is unable to address key bottleneck concerns and the factors that contribute to the cost of being landlocked. Consequently, the impact of massive investment on trade corridors could not materialize to its full extent. Based on extensive data collection in several regions of the world, this book argues that although landlocked developing countries do face high logistics costs, these costs are not a result of poor road infrastructure, since transport prices largely depend on trucking market structure and implementation of transit processes. This book suggests that high logistics costs in LLDCs are a result of low logistics reliability and predictability, which stem from rent-seeking and governance issues. \u27The Cost of Being Landlocked\u27 will serve as a useful guide for policy makers, supervisory authorities, and development agencies
Evolutionary Algorithm with Geometrical Heuristics for Solving the Close Enough Traveling Salesman Problem: Application to the Trajectory Planning of an Unmanned Aerial Vehicle
Evolutionary algorithms have been widely studied in the literature to find sub-optimal solutions to complex problems as the Traveling Salesman Problem (TSP). In such a problem, the target positions are usually static and punctually defined. The objective is to minimize a cost function as the minimal distance, time or energy. However, in some applications, as the one addressed in this paper—namely the data collection of buried sensor nodes by means of an Unmanned Aerial Vehicle— the targets are areas with varying sizes: they are defined with respect to the radio communication range of each node, ranging from a few meters to several hundred meters according to various parameters (e.g., soil moisture, burial depth, transmit power). The Unmanned Aerial Vehicle has to enter successively in these dynamic areas to collect the data, without the need to pass at the vertical of each node. Some areas can obviously intersect. That leads to solve the Close Enough TSP. To determine a sub-optimal trajectory for the Unmanned Aerial Vehicle, this paper presents an original and efficient strategy based on an evolutionary algorithm completed with geometrical heuristics. The performances of the algorithm are highlighted through scenarios with respectively 15 and 50 target locations. The results are analyzed with respect to the total route length. Finally, conclusions and future research directions are discussed
Adaptive Robot Control Based on Wireless Underground Sensor Network in Agriculture 4.0
International audienceFrom sensor nodes fully buried at a few dozens of centimeters deep in Wireless Underground Sensor Networks (WUSN), the soil moisture information can be measured anywhere, including in the passage of vehicles. This opens new opportunities, in particular in Agriculture 4.0, to adapt the speed and work of agricultural mobile robots to the ground conditions. By integrating a collector node in a robot, connected to its CAN bus, this paper experimentally demonstrates the possibility to adapt in real time the speed of the robot with respect to the soil moisture information transmitted in LoRa by a buried sensor node. The hardware and software developements are presented, and the first experimental results discussed. Future research directions are given to extend the capabilities of the system proposed. The innovative approach presented in thispaper enables to envision new possibilities in the combination of WUSN and robotics technologies
Data Collection from Buried Sensor Nodes by Means of an Unmanned Aerial Vehicle
International audienceThe development of Wireless Underground Sensor Networks (WUSNs) is a recent research axis based on sensor nodes buried a few dozen centimeters deep. The communication ranges are, however, highly reduced due to the high attenuation of electromagnetic waves in soil, leading to issues of data collection. This paper proposes to embed a data collector on an Unmanned Aerial Vehicle (UAV) coming close to each buried sensor node. The whole system was developed (sensor nodes, data collector, gateway) and experimentations were carried out in real conditions. In hovering mode, the measurements on the RSSI levels with respect to the position of the UAV highlight the interest in maintaining a high altitude when the UAV is far from the node. In dynamic mode, the experimental results demonstrate the feasibility of carrying out the data collection task while the UAV is moving. The speed of the UAV has, however, to be adapted to the required time to collect the data. In the case of numerous buried sensor nodes, evolutionary algorithms are implemented to plan the trajectory of the UAV optimally. To the best of our knowledge, this paper is the first one that reports experiment results combining WUSN and UAV technologies
Internet of Underground Things in Agriculture 4.0: Challenges, Applications and Perspectives
Internet of underground things (IoUTs) and wireless underground sensor networks (WUSNs) are new technologies particularly relevant in agriculture to measure and transmit environmental data, enabling us to optimize both crop growth and water resource management. The sensor nodes can be buried anywhere, including in the passage of vehicles, without interfering with aboveground farming activities. However, to obtain fully operational systems, several scientific and technological challenges remain to be addressed. The objective of this paper is to identify these challenges and provide an overview of the latest advances in IoUTs and WUSNs. The challenges related to the development of buried sensor nodes are first presented. The recent approaches proposed in the literature to autonomously and optimally collect the data of several buried sensor nodes, ranging from the use of ground relays, mobile robots and unmanned aerial vehicles, are next described. Finally, potential agricultural applications and future research directions are identified and discussed