Current Trajectory Research Articles

National Board of Examination in Medical Sciences (NBEMS): Current and Future Trajectories — Part–1

National Board of Examination in Medical Sciences (NBEMS): Current and Future Trajectories — Part–1

Imagining Anglo-Saxon England: Utopia, Heterotopia, Dystopia

Imagining Anglo-Saxon England: Utopia, Heterotopia, Dystopia

SEEM: A Sequence Entropy Energy-Based Model for Pedestrian Trajectory All-Then-One Prediction.

Predicting the future trajectories of pedestrians is of increasing importance for many applications such as autonomous driving and social robots. Nevertheless, current trajectory prediction models suffer from limitations such as lack of diversity in candidate trajectories, poor accuracy, and instability. In this paper, we propose a novel Sequence Entropy Energy-based Model named SEEM, which consists of a generator network and an energy network. Within SEEM we optimize the sequence entropy by taking advantage of the local variational inference of f-divergence estimation to maximize the mutual information across the generator in order to cover all modes of the trajectory distribution, thereby ensuring SEEM achieves full diversity in candidate trajectory generation. Then, we introduce a probability distribution clipping mechanism to draw samples towards regions of high probability in the trajectory latent space, while our energy network determines which trajectory is most representative of the ground truth. This dual approach is our so-called all-then-one strategy. Finally, a zero-centered potential energy regularization is proposed to ensure stability and convergence of the training process. Through experiments on both synthetic and public benchmark datasets, SEEM is shown to substantially outperform the current state-of-the-art approaches in terms of diversity, accuracy and stability of pedestrian trajectory prediction.

Strategies for sustainable transportation in road way system in urban areas

The current trajectory of the global transportation system is widely acknowledged to be unsustainable. Many people think it's time for a radical shift in how things are done, how things look, how money is spent, and so on. New technologies will have varying long-term negative implications across all cultures, developed and developing alike. The growing interest in the alternative method to sustainable development may be attributed to the convergence of concerns about environmental quality, social equality, economic viability, and treatment of climate change due to rising CO2. Because sustainable growth is crucial for the future of any era, but particularly in this century, it deserves a lot of attention in this article. Society, the economy, and the environment are the three main components of sustainable development in the transportation industry. Sustainable transport needs equilibrium between these three areas to meet its minimum requirements. The importance of transportation to sustainable development must be bolstered by implementing sustainable practices. These tactics include public transportation advocacy, demand management, better road management, pricing regulations, vehicle technological advancements, the use of clean fuels, cultural enrichment, and transportation planning. In this research, we assess how transportation factors into sustainable development initiatives and what impact such methods have.

A Novel Two-Phase Mode Switching Control Strategy for PMSM Position Servo Systems With Fast-Response and High-Precision

In this article, a novel mode switching control (MSC) strategy is proposed containing a fast-response phase and a high-precision settling phase to meet the requirement of high-quality point-to-point permanent magnet synchronous motor servo systems. In the fast-response stage, an adaptive trajectory planning method is developed to program the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">q</i> -axis current profile online based on the reference for the motor to reach the neighborhood of the reference position in minimum time. The chattering in the conventional time-optimal control is overcome and the idea that skipping speed and position loop with preplanned <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">q</i> -axis current trajectory is first attempted. After switching, the high-precision settling stage that is responsible for improving the transient performance in terms of reducing the overshoot and settling time is built with the proposed robust composite nonlinear feedback (RCNF) control law. This RCNF method cancels the overall disturbance through an extended state observer. The switching condition for the proposed MSC controller is clarified. Afterward, the whole closed-loop system's stability is strictly proved. Experiments are then conducted based on different scenarios to prove the effectiveness and robustness of the proposed MSC method.

EXCHANGE AND COORDINATION: CHALLENGES OF THE GLOBAL ONE HEALTH MOVEMENT

Current economic, social, and environmental trajectories within most world regions are unsustainable. Interaction between bottom-up initiatives and top-down good governance is essential to change them. The One Health movement, made up of many organizations, groups, and individuals from diverse backgrounds and disciplines, seeks to redress the present trajectories but has lacked coordination and cooperation, limiting its effectiveness to date. We take a snapshot of groups/organizations working to promote One Health, explore options to increase cooperation and coordination among global One Health stakeholders, and propose systemic strategies that could positively impact animals, people, the planet, plants, and politics.Methods: Through a review of the compilation of Who’s Who in One Health organizations on the One Health Commission’s (OHC) website and the list of organizations that have pledged support for One Health listed on the One Health Initiative (OHI) website, 289 organizations were identified (as of 29 July 2022: 126 Civil Society Organizations, 133 academic and 30 governmental organizations). A stratified sampling approach and MAXQDA 2022 were used in a mixed-methods analysis to select a sample (N=50) of organizations to evaluate with 10 questions on purpose &amp; focus, structure &amp; transparency, cooperation &amp; implementation, and publications. Results: The words “One Health” appeared in the organizations’ names on 62.0% (N=31) of websites examined, most often those in academic settings (78.2%). As regards transparency of the organizational structures, membership was defined in 70.0% (N=35), again most often by academic organizations (82.6%). Members of the governing structures were named on 34.0% of organizational websites. Projects led in the last two years were described on 32.0%, and cooperation with other organizations was indicated on 64.0% of websites examined. Relevant publications and annual reports were listed on 46.0% and 24.0% of probed websites, respectively. Ranking the number of positive findings for each of the 50 organizations examined revealed that full information for all ten questions was provided by only 4 academic and 1 governmental organization.The OHC website was used as a starting point and thus was not included in the N=50 samples. It was therefore examined as an example of a Non-Profit / CSO working to support bottom-up One Health leadership. Since 2014 the OHC has supported a Global One Health Community listserv of individuals from around the globe. The analysis revealed a dominance of Directors from the US and a high proportion of organizations included on the OHC Who’s Who in One Health organizations webpage were located in North America. The social sciences - sociology and economics in particular – were underrepresented among in its leadership. Conclusion: These 10 questions may not have been fully appropriate for all organizations examined in academic or government settings versus stand-alone non-profit or civil society organizations. However, an examination of the 50 selected websites of organizations working to implement One Health and/or framing their projects and purpose in One Health revealed the global One Health movement to be fragmented and uncoordinated. The authors propose to form a more unified voice for One Health across the international One Health movement, a fully networked, informal global One Health alliance or community of practice that can coordinate sharing of information among the networks and with the general public, and that is able to seek synergies and joining of hands in collective/collaborative actions to effectively and efficiently promote and support bottom-up efforts.

A residual convolutional neural network with multi-block for appliance recognition in non-intrusive load identification

Non-intrusive load monitoring (NILM) is a promising technique for energy consumption monitoring that can recognize load states and appliance types without relying on excessive sensing meters. With the development of the Internet of Things in intelligent buildings, the NILM technique will have broad application prospects. According to the different characteristics of load electrical signals, this work constructs 2D load signatures, including building the weighted voltage–current (WVI ) trajectory image, Markov Transition Field (MTF) image, and current spectral sequence-based GAF (I-GAF) image. Furthermore, a deep learning model named Residual Convolutional Neural Network with Energy-normalization and Squeeze-and-excitation blocks (EN-SE-RECNN) is proposed to mine information on the constructed load signatures and realize the appliance identification task. The accuracy of the proposed method on PLAID, WHITED, and HRAD datasets reached 97.43%, 95.99%, and 98.14%, respectively. And it shows that the proposed method significantly improves the recognition performance compared to existing methods.

Realising the promises of agricultural big data through a Māori Data Sovereignty approach

ABSTRACT This perspective piece considers how principles of Māori Data Sovereignty can bring us closer to realising some of the social and environmental promises of new AgTech and the agricultural big data they produce. Our analysis is situated within the settler colonial context of Aotearoa New Zealand. We consider how obligations detailed within treaties guaranteeing equal partnership and Māori self-determination provide the foundation for: (1) acknowledging how the promises of agricultural big data depend on the people, priorities, practices and power relations that guide and enact them; and (2) creating the space to question and challenge current trajectories to ensure agricultural big data are collected and used in ways that promote data sovereignty and an equitable distribution of benefits. We argue that, due to their treaty obligations, publicly-funded projects developing AgTech and agricultural big data analytics in and for Aotearoa must begin developing equity- and sovereignty-promoting data management and governance practices.

Time-Optimal Current Control of Synchronous Motor Drives

We are concerned with the problem of fast and accurate tracking of currents in the general synchronous drive. The problem becomes complicated with decreasing available voltage, which is common in high-speed and field weakening regimes. The existing time-optimal controllers rely on a simplified model, ignoring stator resistance and differences in inductances. We derive a solution for the general model considering all parameters and show how the parameters affect the current trajectory. One simplifying assumption had to be made, but we show in simulation that it has a negligible impact on accuracy. The simplification allowed for the design of a feed-forward controller that has a low computational cost and can be easily implemented in realtime. We provide experimental validation of the controller on the developed IPMSM drive prototype of the rated power of 4.5 kW using conventional industrial DSP. The controller is compared to conventional PI and deadbeat solutions, demonstrating that the time-optimal controller can reach the required setpoint four times faster than the competitors at the field weakening regime of the drive. The proposed feed-forward control can be seen as a universal building block that can be combined with existing feedback controllers and observers and thus incorporated into existing control solutions.

The projected burden of non-communicable diseases attributable to overweight in Brazil from 2021 to 2030

Although studies have quantified the current burden of diseases attributable to overweight and obesity in Brazil, none have estimated its burden in the future. The study aimed to estimate the potential impact of different scenarios of changes in the prevalence of overweight on non-communicable diseases (NCD) in the Brazilian adult population until 2030. We developed a multistate life table model including 11 body mass index (BMI) related diseases to estimate attributable NCDs cases and deaths under the following scenarios of changes in overweight over a 10-year simulation: (1) the continuity of the current trajectory of BMI increases, (2) reducing the rate of increase by half, (3) stopping future BMI increases, and (4) the reduction of the prevalence of overweight by 6.7%. In Brazil, if the current trends of BMI increase are maintained from 2021 to 2030, approximately 5.26 million incident cases and 808.6 thousand deaths from NCDs may occur due to overweight. If the annual increase in overweight was reduced by half until 2030, 1.1% of new NCD cases and 0.2% of deaths could be prevented (respectively, 29,600 cases and 1900 deaths). Alternatively, if the current prevalence of overweight is maintained, as set as a national goal in Brazil until 2030, the incident NCD cases and the deaths could be reduced by respectively 3.3% (92,900) and 1.5% (12,100) compared to continuation of current trends. If the prevalence of overweight is reduced by 6.7% until 2030, 6.5% (182,200) of NCD cases and 4.2% (33,900) of deaths could be prevented. The epidemiologic burden of overweight in Brazil tends to increase if bold policy interventions are not adopted in Brazil.

Updated estimates of large and medium vessel strokes, mechanical thrombectomy trends, and future projections indicate a relative flattening of the growth curve but highlight opportunities for expanding endovascular stroke care

BackgroundA study was undertaken to determine the incidence of acute ischemic stroke (AIS) and strokes related to large (LVO) and medium (MVO) vessel occlusions, and to estimate annual mechanical thrombectomy...

Threat management priorities for conserving Antarctic biodiversity.

Antarctic terrestrial biodiversity faces multiple threats, from invasive species to climate change. Yet no large-scale assessments of threat management strategies exist. Applying a structured participatory approach, we demonstrate that existing conservation efforts are insufficient in a changing world, estimating that 65% (at best 37%, at worst 97%) of native terrestrial taxa and land-associated seabirds are likely to decline by 2100 under current trajectories. Emperor penguins are identified as the most vulnerable taxon, followed by other seabirds and dry soil nematodes. We find that implementing 10 key threat management strategies in parallel, at an estimated present-day equivalent annual cost of US$23 million, could benefit up to 84% of Antarctic taxa. Climate change is identified as the most pervasive threat to Antarctic biodiversity and influencing global policy to effectively limit climate change is the most beneficial conservation strategy. However, minimising impacts of human activities and improved planning and management of new infrastructure projects are cost-effective and will help to minimise regional threats. Simultaneous global and regional efforts are critical to secure Antarctic biodiversity for future generations.

Inductionless control of high speed permanent magnet synchronous motor in full speed range based on neural network

In order to solve the problems of high control error, large maximum output torque and long control time in the traditional full speed range sensorless control method of high-speed permanent magnet synchronous motor, a full speed range sensorless control method of high-speed permanent magnet synchronous motor based on neural network is proposed in this paper. Analyze the range of stator current trajectory in rotor coordinate system, so as to build the discrete model of permanent magnet synchronous motor, and build the whole process control model of high-speed permanent magnet synchronous motor by using neural network algorithm. Through the design of observer, overall control structure and speed regulation range of non inductance control, the goal of non inductance control in the full speed range of high-speed permanent magnet synchronous motor is achieved. The experimental results show that the non inductive control error in the full speed range of the high-speed permanent magnet synchronous motor is 0.2, the maximum output torque is 420 N⋅m, and reaches 2000 r/min at 0.6 s. The practical application effect is good.

Kornelis H. Miskotte’s Biblical ABC s

Abstract Kornelis H. Miskotte's theology generally, and his Biblical ABC s—an important wartime work newly translated into English—in particular represent a welcome provocation to contemporary Christian theology. This essay assesses the key theological claims at the heart of the work, reflects critically upon their meaning and significance, and then draws them into converation with a number of current trends and trajectories in current theological research and writing. In this way, the significance of the work in its own right as well as its—perhaps surprising—relevance to the present theological discussion is brought to light.

A Generalized Current Trajectory Based Fault Diagnostic Method for Three-Phase Two-Level Inverters

Inverters play a vital role in the distributed generated energy systems. Hence, the reliability of the entire distributed energy system depends on the consistent and continuous operation of the inverter. Consequently, to maintain a reliable operation, effective condition monitoring and fault diagnostic schemes have to be incorporated. In this paper, a method based on current trajectory is analyzed for the fault detection and diagnosis of open-switch faults in three-phase two-level voltage source inverters (VSI). The current trajectory-based method of fault diagnosis has been already presented literature for the identification and localization of open-switch fault in the three-phase two-level VSI. The main drawback of the existing current trajectory method is that the fault diagnosis and detection is dependent on the phase currents selected to plot the current trajectories. Therefore, in this paper, a generalization is proposed for the fault diagnosis and diagnosis based on the current trajectory, which make the method independent of the selection of the phase current used to plot the current trajectory. The validity and effectiveness of the proposed generalization is verified by simulation and experiments in a laboratory prototype of three-phase two-level VSI.

An online reliable local trajectory planner for quadrotors

PurposeThis paper aims to propose an online local trajectory planner for safe and fast trajectory generation that combines the jerk-limited trajectory (JLT) generation algorithm and the particle swarm optimization (PSO) algorithm. A trajectory switching algorithm is proposed to improve the trajectory tracking performance. The proposed system generates smooth and safe flight trajectories online for quadrotors.Design/methodology/approachFirst, the PSO algorithm method can obtain the optimal set of target points near the path points obtained by the global path searching. The JLT generation algorithm generates multiple trajectories from the current position to the target points that conform to the kinetic constraints. Then, the generated multiple trajectories are evaluated to pick the obstacle-free trajectory with the least cost. A trajectory switching strategy is proposed to switch the unmanned aerial vehicle (UAV) to a new trajectory before the UAV reaches the last hovering state of the current trajectory, so that the UAV can fly smoothly and quickly.FindingsThe feasibility of the designed system is validated through online flight experiments in indoor environments with obstacles.Practical implicationsThe proposed trajectory planning system is integrated into a quadrotor platform. It is easily implementable onboard and computationally efficient.Originality/valueThe proposed local planner for trajectory generation and evaluation combines PSO and JLT generation algorithms. The proposed method can provide a collision-free and continuous trajectory, significantly reducing the required computing resources. The PSO algorithm locally searches for feasible target points near the global waypoint obtained by the global path search. The JLT generation algorithm generates trajectories from the current state toward each point contained by the target point set. The proposed trajectory switching strategy can avoid unnecessary hovering states in flight and ensure a continuous and safe flight trajectory. It is especially suitable for micro quadrotors with a small payload and limited onboard computing power.

The characteristics of regeneration failure and their potential to shift wet temperate forests into alternate stable states

Under the current trajectory of accelerated climatic and environmental change, many forests are at risk of regeneration failure and subsequent transition to alternate stable states including non-forests or grassland. These regimes shifts can have severe ecological impacts and compromise carbon stores, undermine climate change mitigation, and create conditions incompatible with the survival of biodiversity. However, detailed empirical-based understanding of the alternative states associated with disturbance regime shifts is limited. Here, using a manipulative experiment, and controlling for seed application, we document temporal patterns of vegetation structure and composition associated with regeneration failure after clearcut logging in the ash-type eucalypt forests in south-eastern Australia. Our findings clearly demonstrate that in the absence of direct seed input, frequent stand-replacing disturbance can result in regeneration failure in these forests leading to them being replaced by low species diversity Acacia woodland. These insights can be extrapolated to scenarios of post-fire regeneration failure, where frequent fire precludes the development of adequate seed-stores (<21 years). Such shifts to alternative stable states can have severe ecological implications which require management intervention to circumvent and conserve the functional integrity of these forests. Our case study demonstrates the value of manipulative empirical experiments in quantifying the potential aftermath of forest regeneration failure. Such experiments may be useful to support theories and models in quantifying the ecological implications of regeneration failure, and to guide the application of management interventions for restoration where empirical-based knowledge of these states is limited.

Gradient-Based Predictive Pulse Pattern Control of Medium-Voltage Drives—Part I: Control, Concept, and Analysis

This article proposes a control and modulation strategy for medium-voltage (MV) drives that exhibits excellent steady-state and transient behavior. Specifically, optimized pulse patterns (OPPs) and direct model predictive control are employed so that the associated advantages of both, such as minimum stator current total demand distortion (TDD) and fast transients, respectively, are fully exploited. To do so, the current reference trajectory tracking and modulation problems are addressed in a coordinated manner in the form of a constrained optimization problem that utilizes the knowledge of the stator current evolution—as described by its gradient—within the prediction horizon. Solving this problem yields the optimal real-time modification of the offline-computed OPP, which guarantees that very low—and close to its theoretical minimum value—stator current TDD is produced at steady state, and very short settling times during transients. To highlight the effectiveness of the proposed strategy, a variable speed drive system consisting of a three-level neutral point clamped inverter and an MV induction machine serves as a case study.

Gradient-Based Predictive Pulse Pattern Control of Medium-Voltage Drives—Part II: Performance Assessment

In this article, the performance of gradient-based predictive pulse pattern control (GP <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^{3}$</tex-math></inline-formula> C) is evaluated for a medium-voltage variable-speed drive consisting of a three-level neutral-point-clamped (NPC) inverter and a medium-voltage induction machine. To this end, real-time tests are performed in a hardware-in-the-loop (HIL) environment, which, along with extensive simulation studies, elucidate the potential of performance gains achieved with GP <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^{3}$</tex-math></inline-formula> C. As shown, by manipulating offline-computed optimized pulse patterns (OPPs) in real time such that the stator current of the machine follows a precalculated optimal current trajectory, superior steady-state and transient performance can be achieved. Specifically, the current total demand distortion (TDD) is significantly reduced compared with established control methods, such as field-oriented control (FOC) with space vector modulation (SVM), while shorter settling times during transients are achieved. Finally, to complete the assessment of the control method of interest, real-time implementation aspects are discussed in detail.

Tropical peatlands in the Anthropocene: The present and the future

Tropical peatlands are a globally important carbon store. They host significant biodiversity and provide a range of other important ecosystem services, including food and medicines for local communities. Tropical peatlands are increasingly modified by humans in the rapid and transformative way typical of the “Anthropocene,” with the most significant human—driven changes to date occurring in Southeast Asia. This review synthesizes the dominant changes observed in human interactions with tropical peatlands in the last 200 years, focusing on the tropical lowland peatlands of Southeast Asia. We identify the beginning of transformative anthropogenic processes in these carbon-rich ecosystems, chart the intensification of these processes in the 20 th and early 21 st centuries, and assess their impacts on key ecosystem services in the present. Where data exist, we compare the tropical peatlands of Central Africa and Amazonia, which have experienced very different scales of disturbance in the recent past. We explore their global importance and how environmental pressures may affect them in the future. Finally, looking to the future, we identify ongoing efforts in peatland conservation, management, restoration, and socio-economic development, as well as areas of fruitful research toward sustainability of tropical peatlands. • Tropical peatlands are under threat from ongoing human impact in the Anthropocene. • Not all tropical peatlands have been equally exposed to human influences in the past, and many peatlands provide vital ecosystem services for local communities • Current trajectories for climate and land use change disturbances differ between the three major tropical peatland regions • Local to global initiatives and partnerships (for example the Global Peatlands Initiative) allow the sharing of knowledge between actors and provide an opportunity to improve peatland outcomes, including restoration and conservation