natural dynamics
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2022 ◽  
Vol 9 (1) ◽  
Author(s):  
María Fernanda Ordóñez ◽  
Kelly Shannon ◽  
Viviana d’Auria

AbstractIn 2008, Ecuador became the first country in the world to declare nature as a subject of rights based on the ‘Buen Vivir’ (Good Living) philosophy which is premised on an indigenous principle that envisions a world where humans are part-and-parcel of a larger natural and social environment. Although Ecuador’s constitution is groundbreaking from a legal standpoint, the question arises of how the rights of nature is spatially manifested beyond the designation of protected areas? To shed light on such interrogation, this article, based on qualitative research, focuses on the linear park component of the mega-project Guayaquil Ecológico heralded as a first materialization which champions the “Rights of Nature” under the vision of the Buen Vivir. It unravels the contested rhetoric and realities of the Guayaquil Ecológico linear park in a critical review of the as-built project in relation to the larger objectives of Buen Vivir. The Guayaquil Ecologico linear park promised to simultaneously upgrade both social and environmental dimensions. However, it did not fully address the complexity of Guayaquil’s socio-ecological context and some of the structural injustices of the estuarine territory. Buen Vivir was rhetorically mobilised to implement a project where aesthetic dimensions dominated, further perpetuating socio-ecological vulnerabilities through relocation and evictions. Furthermore, its implementation was dependent on a specific political moment, leaving it in a state of abandonment and neglect. The Buen Vivir philosophy—as a decolonial stance that challenges western forms of development—can offer a fundamental base to question current modes of territorial occupation based on extractivist planning and design strategies. It holds significant potential to serve as base to re-think the relationship between forms of settlement, natural dynamics, and worldviews.


2021 ◽  
Vol 14 (6) ◽  
pp. 3255
Author(s):  
Alessandra De Santana Lima ◽  
Camila Gardenea de Almeida Bandim ◽  
Gabriel Antonio Silva Soares ◽  
Juliana Patrícia Fernandes Guedes Barros ◽  
Josiclêda Domiciano Galvíncio

Os grandes aglomerados urbanos desencadeiam profundas problemáticas de natureza hidroclimática, resultantes principalmente das formas de uso e ocupação do solo. Os padrões hídricos, tais como escoamento e acúmulo de fluxo, são afetados diretamente pelo efeito de impermeabilização do solo decorrente das construções humanas e quando esta estrutura urbana é somada aos eventos climáticos extremos, culminam na ocorrência periódica de inundações. Diante deste contexto, o presente estudo tem como objetivo compreender e identificar os danos hidrológicos decorrentes da concentração urbana, sobre a dinâmica natural do escoamento, a fim de investigar os fatores que provocam estas inundações nas determinadas regiões. A área de estudo do presente trabalho é representada por folhas de amostragem do sensor LiDAR das Regiões político administrativas IV e VI do município do Recife, Pernambuco. Para subsidiar a análise proposta, os modelos digitais de elevação do projeto Pernambuco 3D, provenientes do sensor LiDAR, foram processados em ambiente SIG, e a partir destes dados de alta resolução espacial foi possível analisar detalhadamente as variáveis que propiciam o escoamento superficial e acúmulo de fluxo nas áreas em estudo. Os resultados obtidos para as áreas de amostragem, foram analisados e comparados com as políticas públicas de drenagem urbana e planejamento territorial vigentes, avaliando a relação entre as redes de macro e microdrenagem, com a ocorrência de inundações no meio urbano. The use of lidar data for the understanding of water flow and accumulation dynamics in the Recife – PEA B S T R A C TLarge urban agglomerations result in huge problems of hydroclimatic nature, resulting mainly from the forms of land use and occupation. Water patterns, such as runoff and flow accumulation, are directly affected by the waterproofing effect from human constructions, and when added to the extreme weather events, they culminate in a periodic occurrence of urban floods. The study area of the present work is represented by the LiDAR sensor sampling sheets from the administrative political Regions IV and VI of the municipality of Recife, in Pernambuco. Given this context, the present study aims to understand and identify the hydrological damage caused by the urban concentration on the natural dynamics of runoff, to investigate the factors that cause these floods in that specific region. To subsidize the proposed analysis, the digital elevation models of the Pernambuco 3D project, from the LiDAR sensor, were processed in a GIS environment, and from these high spatial resolution data it was possible to analyze in detail the variables that propitiate surface runoff and flow accumulation in the areas under study. The results obtained for the sampling areas were analyzed and compared with the urban drainage and territorial planning public policies in force, evaluating the relationship between the macro and micro drainage networks, with the occurrence of floods in the urban environment. Keywords: Geoprocessing. remote sensing. urbanization. urban flood. surface runoff.


2021 ◽  
Vol 13 (24) ◽  
pp. 14006
Author(s):  
Carla Victoria Ramirez-Lopez ◽  
Leticia Castano ◽  
Patricia Aldape ◽  
Santa Tejeda

One of the most significant challenges of telepresence distance education is to bring the professor and the students closer together in a synchronistic educational experience where the professor is perceived as anatomically proportionate. Telepresence, an educational technology ecosystem using holograms, offers a way to solve this technological challenge. Our mixed exploratory research investigating this methodology had two purposes: (1) propose the key elements to teach distance courses synchronously in an educational technology ecosystem, and (2) demonstrate the technological, didactic practices that result in positive student learning outcomes in several specified courses. This methodology included applying a student questionnaire to collect their perceptions of the educational experience. The scores and written comments from the questionnaire were analyzed using Grounded Theory. On a Likert scale from 1 to 5, the students scored their educational experience, attaining a mean of 4.05. The positive perception affirmed that they valued: (a) recreating the natural dynamics of face-to-face classes, where the students perceived their professors as being physically present in the classroom; (b) professors renowned in their disciplines; (c) professor–student and campus and intercampus learning community interactions, and, finally, (d) class design and content. The main conclusions of this research were that students positively perceived the “wow” effect of the technology, feeling comfort, amazement, interest, and engagement. In addition, we found that professors and keynote speakers with excellent pedagogical skills and experts in their disciplines were well appreciated. Key elements for the success of the experience were professor–student, campus, and intercampus interactions and the quality of the technological and communication infrastructure.


2021 ◽  
Author(s):  
Sigit D Sasmito ◽  
Pierre Taillardat ◽  
Letisha Fong ◽  
Jonathan Ren ◽  
Hanna Sundahl ◽  
...  

Author(s):  
Kuan-Yu Tseng ◽  
Pei-Chun Lin

Abstract This article introduces a model-based strategy for a quadruped robot with differentiated fore- and hind-leg ground reaction-force patterns to generate animal-like running behavior. The proposed model comprises a rigid body and two eSLIP legs with dampers. The eccentric-SLIP (eSLIP) model extends the traditional spring-loaded inverted pendulum (SLIP) model by adding a bar to offset the spring direction. The proposed two-leg eSLIP (TL-eSLIP) model’s fore- and hind legs were designed to have the same offset magnitude but in opposite offset directions, producing different braking and thrusting force patterns. The TL-eSLIP model’s reference leg trajectories were designed based on the fixed-point motion of the eSLIP model. Additionally, the legs were clock torque-controlled to modulate leg motion and stabilize the model to follow its natural dynamics. The model’s equations for motion were derived, and the model’s dynamic behavior was simulated and analyzed. The simulation results indicate that the model with leg offsets and in either trotting or pronking has differentiated leg force patterns, and it is more stable and has larger basins of attraction than the model without leg offsets. A quadruped robot was built for experimental validation. The experimental results demonstrate that the robot with differentiated legs ran with differentiated ground reaction force patterns and ran more stably than another robot with the same leg morphology.


2021 ◽  
pp. 179-202
Author(s):  
Jorge Daniel Taillant

This chapter introduces the concept of the periglacial environment, an area of frozen ground that is rich in hydrological resources. Periglacial environments provide drinking water to significant portions of the Earth’s population and are home to the enigmatic and almost unknown rock glaciers, which are subterranean rivers of ice, invisible to the naked eye unless you know where to look for them. The chapter offers the reader many pictures of rock glaciers around the world and describes the hydrological function and the natural dynamics of the periglacial environment and how it captures water from the atmosphere, freezes it, and then re-injects it into the ecosystem.


2021 ◽  
Author(s):  
Felix Ruppert ◽  
Alexander Badri-Spröwitz

Abstract Legged robots have the potential to show locomotion performance with reduced control effort and energy efficiency by leveraging elastic structures inspired by animals' elastic tendons and muscles. However, it remains a challenge to match the natural dynamics of complex legged robots and their control task dynamics. Here we present a framework to match control task dynamics and natural dynamics based on the neuroelasticity and neuroplasticity concept. Inspired by animals we design quadruped robot Morti with strong natural dynamics as a testing platform. It is controlled through a bioinspired closed-loop central pattern generator (CPG) that is designed to neuroelastically mitigate short term perturbations using sparse contact feedback. We use the amount of neuroelastic activity as a proxy to quantify the dynamics' mismatching. By minimizing neuroelastic activity, we neuroplastically match the control task dynamics to the robot's natural dynamics. Through matching the robot learns to walk within one hour with only sparse feedback and improves its energy efficiency without explicitly minimizing it in the cost function.


2021 ◽  
Author(s):  
Xuwei Wu ◽  
Christian Ott ◽  
Alin Albu-Schäffer ◽  
Alexander Dietrich

Kinematic redundancy in robots makes it possible to execute several control tasks simultaneously. As some tasks are usually more important than others, it is reasonable to dynamically decouple them in order to ensure their execution in a hierarchical way or even without any interference at all. The most widely used technique is to decouple the system by feedback linearization. However, that requires to actively shape the inertia and consequently modify the natural dynamics of the robot. Here we propose a passivity-based multi-task tracking controller that preserves these inertial properties but fully compensates for task-space cross-couplings using external force feedback. Additionally, three formal proofs are provided: uniform exponential stability for trajectory tracking, passivity during physical interaction, and input-to-state-stability. The controller is validated in simulations and experiments and directly compared with the hierarchical PD+ approach and the feedback linearization. The proposed approach is well suited for safe physical human-robot interaction and dynamic trajectory tracking if measurements or estimations of the external forces are available.


2021 ◽  
Author(s):  
Xuwei Wu ◽  
Christian Ott ◽  
Alin Albu-Schäffer ◽  
Alexander Dietrich

Kinematic redundancy in robots makes it possible to execute several control tasks simultaneously. As some tasks are usually more important than others, it is reasonable to dynamically decouple them in order to ensure their execution in a hierarchical way or even without any interference at all. The most widely used technique is to decouple the system by feedback linearization. However, that requires to actively shape the inertia and consequently modify the natural dynamics of the robot. Here we propose a passivity-based multi-task tracking controller that preserves these inertial properties but fully compensates for task-space cross-couplings using external force feedback. Additionally, three formal proofs are provided: uniform exponential stability for trajectory tracking, passivity during physical interaction, and input-to-state-stability. The controller is validated in simulations and experiments and directly compared with the hierarchical PD+ approach and the feedback linearization. The proposed approach is well suited for safe physical human-robot interaction and dynamic trajectory tracking if measurements or estimations of the external forces are available.


2021 ◽  
pp. 1-41
Author(s):  
Hongbo Yang ◽  
Arika Ligmann-Zielinska ◽  
Yue Dou ◽  
Min Gon Chung ◽  
Jindong Zhang ◽  
...  

AbstractRural areas are increasingly subject to the effects of telecouplings (socioeconomic-environmental interactions over distances) whereby their human and natural dynamics are linked to socioeconomic and environmental drivers operating far away, such as the growing demand for labor and ecosystem services in cities. Although there have been many studies evaluating the effects of telecouplings, telecoulplings in those studies were often investigated separately and how telecoulplings may interact and affect dynamics of rural coupled human and natural systems (CHANS) jointly was rarely evaluated. In this study, we developed an agent-based model and simulated the impacts of two globally common telecouplings, nature-based tourism and labor migration, on forest dynamics of a rural CHANS, China’s Wolong Nature Reserve (Wolong). Nature-based tourism and labor migration can facilitate forest recovery, and the predicted forest areas in Wolong in 2030 would be reduced by 26.2 km2 (6.8%) and 23.9 km2 (6.2%), respectively, without their effects. However, tourism development can significantly reduce the probability of local households to have member(s) out-migrate to work in cities and decrease the positive impact of labor migration on forest recovery. Our simulations show that the interaction between tourism and labor migration can reduce the potential forest recovery by 3.5 km2 (5.0%) in 2030. Our study highlights that interactions among different telecouplings can generate significant impacts on socioeconomic and environmental outcomes and should be jointly considered in the design, management, and evaluation of telecouplings for achieving sustainable development goals.


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