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In the last two decades new emphasis has been given to the economic impact of geography, especially on the cost of being landlocked. From a development perspective, understanding the cost of being landlocked and its economic impact is critical, since one country of four in the world is landlocked (almost one out of three in Sub-Saharan Africa). Attempts to address the cost of being landlocked have mainly focused on regional and multilateral conventions aiming at ensuring freedom of transit, and on the development of regional transport infrastructure. The success of these measures has been limited, and many massive investments in infrastructure seem to have had a disappointing impact on landlocked economies. Although there may still be an infrastructure gap, this book, based on extensive data collection in several regions of the world, argues that logistics and trade services efficiency can be more important for landlocked countries than investing massively in infrastructure. Logistics have become increasingly complex and critical for firms' competitiveness, and a weakness in this field can badly hurt firms based in landlocked countries. This book proposes a revised approach to tackling the cost of being landlocked and a new analytical framework which uses a microeconomic approach to assess the trade and macroeconomic impacts of logistics. It takes into account recent findings on the importance of logistics chain uncertainty and inventory control in firms' performance. It argues that: (i) exporters and importers in landlocked developing countries face high logistics costs, which are highly detrimental to their competitiveness in world markets, (ii) high logistics costs depend on low logistics reliability and predictability, and (iii) low logistics reliability and predictability result mostly from rent-seeking and governance issues (prone to proliferate in low volume environments).

The factors responsible for variation in dispersal distances across species remain poorly understood. Previous comparative studies found differing results and equivocal support for theoretical predictions. Here I re-examine factors that influence natal dispersal distances in British birds while taking into account the cost of transport as estimated from proxies of long-distance flight efficiency. First, I show that flight efficiency, as estimated by the hand-wing index, the aspect ratio, or the lift-to-drag ratio, is a strong predictor of dispersal distances among resident species. Most migratory species showed a similar pattern, but a group of species with relatively low aerodynamic efficiency showed longer-than-expected dispersal distances, making the overall trend independent of flight efficiency. Ecological, behavioral, and life history factors had a small or nil influence on dispersal distances, with most of their influence likely mediated by adaptations for the use of space reflected in flight efficiency. This suggests that dispersal distances in birds are not determined by adaptive strategies for dispersal per se, but are predominantly influenced by the energetic cost of movement.

The metabolic costs of animal movement have been studied extensively under laboratory conditions, although frequently these are a poor approximation of the costs of operating in the natural, heterogeneous environment. Construction of “energy landscapes,” which relate animal locality to the cost of transport, can clarify whether, to what extent, and how movement properties are attributable to environmental heterogeneity. Although behavioral responses to aspects of the energy landscape are well documented in some fields (notably, the selection of tailwinds by aerial migrants) and scales (typically large), the principles of the energy landscape extend across habitat types and spatial scales. We provide a brief synthesis of the mechanisms by which environmentally driven changes in the cost of transport can modulate the behavioral ecology of animal movement in different media, develop example cost functions for movement in heterogeneous environments, present methods for visualizing these energy landscapes, and derive specific predictions of expected outcomes from individual- to population- and species-level processes. Animals modulate a suite of movement parameters (e.g., route, speed, timing of movement, and tortuosity) in relation to the energy landscape, with the nature of their response being related to the energy savings available. Overall, variation in movement costs influences the quality of habitat patches and causes nonrandom movement of individuals between them. This can provide spatial and/or temporal structure to a range of population- and species-level processes, ultimately including gene flow. Advances in animal-attached technology and geographic information systems are opening up new avenues for measuring and mapping energy landscapes that are likely to provide new insight into their influence in animal ecology.

Energetic expenditure is an important factor in animal locomotion. Here we test the hypothesis that fishes control tail-beat kinematics to optimize energetic expenditure during undulatory swimming. We focus on two energetic indices used in swimming hydrodynamics, cost of transport and Froude efficiency. To rule out one index in favour of another, we use computational-fluid dynamics models to compare experimentally observed fish kinematics with predicted performance landscapes and identify energy-optimized kinematics for a carangiform swimmer, an anguilliform swimmer and larval fishes. By locating the areas in the predicted performance landscapes that are occupied by actual fishes, we found that fishes use combinations of tail-beat frequency and amplitude that minimize cost of transport. This energy-optimizing strategy also explains why fishes increase frequency rather than amplitude to swim faster, and why fishes swim within a narrow range of Strouhal numbers. By quantifying how undulatory-wave kinematics affect thrust, drag, and power, we explain why amplitude and frequency are not equivalent in speed control, and why Froude efficiency is not a reliable energetic indicator. These insights may inspire future research in aquatic organisms and bioinspired robotics using undulatory propulsion.

In this article, we propose a 3-dimensional framework for evaluating the costs of transporting goods between Europe and Asia, including direct transport, time, and Environmental Costs (ECs). We estimate the costs of alternative container transport routes, including direct sea transport via the Suez Canal Route (SCR) and the Northern Sea Route (NSR); direct rail connections via the Trans-Siberian Rail (TSR) and the Belt and Road Initiative (BRI), and intermodal transport options consisting of rail and sea transport legs. When considering environmental and Inventory Carrying Costs (ICs), the NSR is viable at least seasonally, whereas rail and intermodal alternatives remain more expensive. The results provide a robust estimate of the potential of alternative transport routes and modes. The inclusion of ECs in our analysis provides valuable new information to stakeholders on how to achieve the ambitious environmental goals while also considering the economic viability of different route options in Europe–Asia container trade.

Which animals use their energy better during movement? One metric to answer this question is the energy cost per unit distance per unit weight. Prior data show that this metric decreases with mass, which is considered to imply that massive animals are more efficient. Although useful, this metric also implies that two dynamically equivalent animals of different sizes will not be considered equally efficient. We resolve this longstanding issue by first determining the scaling of energy cost per unit distance traveled. The scale is found to be M ²/³ or M ¹/², where M is the animal mass. Second, we introduce an energy-consumption coefficient (C E) defined as energy per unit distance traveled divided by this scale. C E is a measure of efficiency of swimming and flying, analogous to how drag coefficient quantifies aerodynamic drag on vehicles. Derivation of the energy-cost scale reveals that the assumption that undulatory swimmers spend energy to overcome drag in the direction of swimming is inappropriate. We derive allometric scalings that capture trends in data of swimming and flying animals over 10–20 orders of magnitude by mass. The energy-consumption coefficient reveals that swimmers beyond a critical mass, and most fliers are almost equally efficient as if they are dynamically equivalent; increasingly massive animals are not more efficient according to the proposed metric. Distinct allometric scalings are discovered for large and small swimmers. Flying animals are found to require relatively more energy compared with swimmers.

In this paper, we propose a locomotion control method for a compliant legged robot from slow walking to fast running. We also examine the energy efficiency of the compliant legged robot controlled by the proposed locomotion control method. Experimentally, we obtain the robot running speed of about 4.3m/s with the initial compliant leg length of 0.1m. In addition, we obtain very good energy efficiency. In the best case, the mechanical cost of transport(Cmt), known as an energy efficiency measure, is obtained at about 0.2. Comparing with the other energy efficient robots, our robot exhibits very good energy efficiency.

Offshore electricity production, mainly by wind turbines, and, eventually, floating PV, is expected to increase renewable energy generation and their dispatchability. In this sense, a significant part of this offshore electricity would be directly used for hydrogen generation. The integration of offshore energy production into the hydrogen economy is of paramount importance for both the techno-economic viability of offshore energy generation and the hydrogen economy. An analysis of this integration is presented. The analysis includes a discussion about the current state of the art of hydrogen pipelines and subsea cables, as well as the storage and bunkering system that is needed on shore to deliver hydrogen and derivatives. This analysis extends the scope of most of the previous works that consider port-to-port transport, while we report offshore to port. Such storage and bunkering will allow access to local and continental energy networks, as well as to integrate offshore facilities for the delivery of decarbonized fuel for the maritime sector. The results of such state of the art suggest that the main options for the transport of offshore energy for the production of hydrogen and hydrogenated vectors are through direct electricity transport by subsea cables to produce hydrogen onshore, or hydrogen transport by subsea pipeline. A parametric analysis of both alternatives, focused on cost estimates of each infrastructure (cable/pipeline) and shipping has been carried out versus the total amount of energy to transport and distance to shore. For low capacity (100 GWh/y), an electric subsea cable is the best option. For high-capacity renewable offshore plants (TWh/y), pipelines start to be competitive for distances above approx. 750 km. Cost is highly dependent on the distance to land, ranging from 35 to 200 USD/MWh.

Humans naturally select conditions to minimize their net cost of transport (COT) during walking. One way to do this is by exploiting the mechanical benefit of arm swing which reduces whole-body rotation about the vertical axis and thus, minimizes the free vertical moment (FVM) that the foot applies to the ground. Humans appear to exploit these benefits of arm swing at speeds that are considered optimal, but we sought to determine if these benefits are conserved across slow to fast walking speeds. If true, arm swing may be a key feature that helps to minimize the net COT regardless of one’s walking speed. We hypothesized that at all speeds, walking with arm swing would be less costly compared to walking without arm swing. As a secondary aim, we also explored if reductions in the peak FVM could explain the metabolic benefits of arm swing. Twenty-one young, healthy subjects walked with and without arm swing at speeds ranging from 0.50 to 2.00 m/s while we recorded metabolic, kinematic and kinetic data. At slow speeds (≤1.00 m/s), net COT was similar when walking with or without arm swing (p > 0.05). However, at intermediate and fast speeds (≥1.00 m/s), arm swing reduced the net COT by ~7–13% (all p’s < 0.05). Additionally, peak FVM magnitudes decreased with arm swing, suggesting that it may partially explain the metabolic benefit of arm swing. Overall, we find that arm swing provides a net metabolic benefit during walking, but this benefit is constrained to intermediate and fast walking speeds.

Stiffness-customized passive-dynamic ankle–foot orthoses (PD-AFOs) have been shown to reduce the mechanical cost of transport (COT) of individuals post-stroke. However, the mechanisms underlying this reduced COT are unknown. Therefore, this study aimed to identify the factors driving COT reduction with PD-AFO use for individuals post-stroke. Results showed that changes in limb work were strongly correlated to changes in COT with the PD-AFO compared to No AFO in the paretic (tau = 0.637, p < 0.001) and non-paretic (tau = 0.621, p < 0.001) limbs. There was also a strong correlation between changes in limb work and changes in COT compared to SOC AFO in the paretic (tau = 0.569, p < 0.001) and non-paretic (tau = 0.503, p = 0.003) limbs. Conversely, changes in stride length and changes in COT were not correlated. Changes in COT between No AFO and PD-AFO were moderately correlated to the number of constituents that performed less mechanical work for both the paretic (tau = −0.462, p = 0.009) and non-paretic (tau = −0.402, p = 0.025) limbs. Compared to walking with SOC AFOs, there was a moderate correlation between COT and the number of constituents in the paretic limb (tau = −0.458, p = 0.011) but not the non-paretic limb (tau = −0.247, p = 0.173). These findings indicate that PD-AFOs reduce COT primarily through small changes in work across many lower limb constituents. Understanding how COT reduction occurs can help optimize PD-AFO design and possibly other rehabilitation interventions for individuals post-stroke.