Current Trajectory Research Articles

Freiheit neu vorstellen: menschliches Handlungsvermögen in Zeiten der ökologischen Katastrophe

Abstract I address the question of human agency from the perspective of critical social theory, starting from the premise that, today, such theories must focus on the global ecological disaster. I assume, furthermore, that radical societal change is necessary in order to arrest our current disastrous ecological trajectory. Radical societal change calls for a fundamental re-orientation in values globally, on both an individual and collective level. This entails a thorough-going change in perceptions of what it means to lead an ethically good life, including revision of deepseated conceptions of ethical agency, in particular, the idea of individual freedom. Wearing the hat of an engaged theorist, I propose a re-imagining and rearticulation of freedom as ecologically attuned, self-directing, self-transforming political agency. Taking social institutions as an example, I discuss non-authoritarian authority as a force for forming and transforming ethical perceptions and attribute a similar non-authoritarian potential to critical social theories, in this case a disclosive one. While a change in ethical perceptions will not be sufficient for the required societal transformation, I claim that it is an integral component of it.

A Multi-Level Attentive Context-Aware Trajectory Prediction Algorithm for Mobile Social Users

The prediction of a user’s trajectory is a key problem in mobility prediction, which has been applied to a range of fields such as location-based service recommendations and traffic planning. The impact of users’ social contacts on mobility is not adequately considered in the current trajectory prediction research. Furthermore, the spatial–temporal dependence of long trajectories is difficult to characterize by conventional recurrent neural network models. A multi-level attentive context-aware trajectory prediction model (MACTP) for mobile social users is proposed in this research to address the above problems. Specifically, users’ social preferences are captured by friend-level attention, and different friends are allocated varying weights. The impact of other check-in points in the trajectory on the present check-in point is considered through check-in-level attention. Trajectory-level attention is used to obtain the representation of historical trajectories influenced by current trajectories, as well as the spatial–temporal dependencies of longer trajectories. Experimental results on two real-world datasets demonstrate that the proposed model significantly improves trajectory prediction performance.

Real-time task-oriented continuous digging trajectory planning for excavator arms

Current digging trajectory planning methods for excavator arms are limited to a single digging cycle, which does not meet the continuous excavation demands of the task. To address this issue, a real-time task-oriented continuous digging trajectory planning method for autonomous excavators is presented. The method involves optimizing digging trajectory for a single excavation cycle using multi-objective PSO method, building a PINN model using optimization results as training samples for real-time planning, and embedding the PINN model in planning framework for typical tasks. The method was validated using four different cross-section shapes of the trench. Results show that the average time taken to plan a single digging trajectory is less than 4.5ms, which is negligible compared to the time taken by PSO. The overall performance of the trajectory is only about 5% different from those planned by PSO. This method offers a more efficient and effective solution for continuous excavation tasks.

Revisiting how scientific research drives technological change: The Fifth Industrial Revolution

Moll, Marwala, and Ntlatlapa highlight salient criticisms of terminologies and definitional uncertainties associated with the term ‘Fourth Industrial Revolution’ (4IR). Scientific research on technological change seems to suggest a need for theoretical synthesis to address a failure of 4IR notions to consider the central role of a revolution in the scientific/knowledge creation process itself – that is seemingly a causal driver of current technological and societal changes. The term ‘Fifth Industrial Revolution’ might helpfully be used to differentiate 4IR debates from those deriving from revolutionary changes in science itself that may underlie our current trajectory of technological change.

Lying to Ourselves: Has the U.S. Navy Become the Imperial Japanese Navy of 1941?

The U.S. Navy’s current trajectory may remind the reader of the Imperial Japanese Navy (IJN) prior to the outbreak of World War II in the Pacific in late 1941. This article argues that many of the same problems the IJN faced against its larger U.S. opponent in World War II exist today in the U.S. Navy’s planning and preparation for possible conflict with the People’s Republic of China. Problems that both navies share include brittle readiness, planning for a short war with a resulting doctrine to match, and a fleet that is too small to sustain any form of attritional war at sea. The article further argues that in many senses the U.S. Navy is less prepared today than was the IJN in 1941. The author provides several recommendations for how to begin to correct these difficulties.

Measurement of the Self-Sensing Capability of Synchronous Machines for High Frequency Signal Injection Sensorless Drives

Signal injection sensor-less control for synchronous machines is known to be afflicted by an estimation error dependent on the load current. The estimation error is related to the cross-saturarion and the saliency of the adopted synchronous machine. A motor can be more or less suitable for signal injection sensorless control compared to other motors with different designs or sizes. A sensorless drive can even be afflicted by the control divergence when the machine is highly saturated, resulting in a useless drive. Moreover, even when the control converges, the actual current control trajectory is different from the given reference. In this paper, a measurement procedure of the convergence region, i.e. the operating points where the motor can be successfully controlled without a position sensor is presented and validated. In particular, two different synchronous motors are considered, a permanent magnet assisted synchronous reluctance motor (PMA-SynRM) and a synchronous reluctance motor (SynRM).

LibCity-Dataset: a standardized and comprehensive dataset for urban spatial–temporal data mining

Abstract The LibCity-Dataset represents a significant contribution to the field of urban spatial-temporal data mining. This dataset uniquely integrates macro traffic state data with micro trajectory data, providing researchers with comprehensive and diverse urban spatial-temporal data. Specifically, we begin by collecting and processing existing open-source spatial-temporal data. Subsequently, we independently collected Beijing taxi trajectory data through third-party interfaces. This data bridges the gap in the scarcity of current open-source vehicle trajectory data. The distinctive aspect of the LibCity-Dataset lies in its innovative approach of standardizing the storage format, achieved through the implementation of atomic files. By adopting this standardized format, diverse data sources are harmonized, enabling effortless application of spatial-temporal prediction models across various datasets. The uniform storage format not only simplifies experimentation but also expedites the advancement of spatial-temporal prediction research, acting as a catalyst for further innovation. This Data Note provides a comprehensive insight into the creation methodology of the LibCity-Dataset, including data collection and processing methodology, data description, data validation, and usage notes. By facilitating open-source collaboration and setting a benchmark for standardization within the spatial-temporal prediction domain, this dataset aims to foster increased research cooperation and knowledge sharing. The open-source link of our dataset is https://drive.google.com/drive/folders/1g5v2Gq1tkOq8XO0HDCZ9nOTtRpB6-gPe.

Pilot Protection Based on Two-Dimensional Space Projection of Dual Differential Currents for Lines Connecting MMC–HVDC Stations

As an important topic of power system protection, protection algorithm for transmission lines connecting MMC-based converter stations has attracted extensive attention. This article proposes a new time-domain pilot protection based on two-dimensional space projection of dual differential currents for lines connecting converter stations. The dual differential currents, i.e., original and virtual differential currents, are projected into two-dimensional space. Subsequently, the dynamic trajectories of dual differential currents under various circumstances are elaborated. On this basis, the non-operating zone and internal fault index are defined, whereby the criterion of pilot protection is developed. Afterwards, the operating characteristic of the proposed pilot protection is analyzed under various circumstances. The performance of proposed pilot protection is widely assessed using PSCAD and RTDS. The contribution of this article lies in a new time-domain pilot protection based current trajectory of dual differential currents, which exhibits exceptional performance in operating speed, sensitivity, complexity, tolerance to fault resistance, CT saturation and abnormal data, adaptability to operation mode of MMC.

Imagining sustainable futures for the high seas by combining the power of computation and narrative

The high seas are experiencing a stark increase in industrial activities, with resources being exploited unsustainably and shared unequally. This suggests the need for a transformation, a shift in the deeper structures of the system such as underlying paradigms and mind-sets. We created future visions by combining computational text analysis with a structured, yet creative futuring approach. This process resulted in four science fiction stories, which aim to capture the complexity of the system, embrace the inherent uncertainty of the future and question current unsustainable trajectories, while emphasizing the vastness of future option space. The visions are analyzed using the concept of imaginaries, demonstrating that futuristic stories can be traced back to current realities and the scientific evidence they were based upon. We argue that engaging with alternative futures can open up transformative spaces to rethink the relationships between humans and the high seas, from which novel imaginaries can emerge.

International risk of food insecurity and mass mortality in a runaway global warming scenario

Climate and agriculture have played an interconnected role in the rise and fall of historical civilizations. Our modern food system, based on open-environment production and globalised supply chains, is vulnerable to a litany of abiotic and biotic stressors exacerbated by anthropogenic climate change. Despite this evidence, greenhouse gas emissions continue to rise. Current trajectories suggest global warming of ∼2.0–4.9 °C by 2100, however, a worst-case emissions scenario with rapid combustion of all available fossil fuels could cause a rise of ∼12 °C. Even if emissions decline, unprecedented atmospheric CO2-e concentrations risk triggering tipping points in climate system feedbacks that may see global warming exceed 8 °C. Yet, such speculative ‘runaway global warming’ has received minimal attention compared to mainstream low- to mid-range scenarios. This study builds on The Limits to Growth to provide new insights into the international risk of mass mortality due to food insecurity based on a higher-resolution illustration of World3’s ‘runaway global warming’ scenario (∼8–12 °C+). Our simulation indicates rapid decline in food production and unequal distribution of ∼6 billion deaths due to starvation by 2100. We highlight the importance of including high-resolution simulations of high-range global warming in climate change impact modelling to make well-informed decisions about climate change mitigation, resilience and adaptation.

Assessment of Potential Recovery Viability for Colorado Pikeminnow Ptychocheilus lucius in the Colorado River in Grand Canyon

Abstract Colorado Pikeminnow Ptychocheilus lucius, the Colorado River's top native predatory fish, was historically distributed from the Gulf of California delta to the upper reaches of the Green, Colorado, and San Juan rivers in the Colorado River basin in the Southwestern United States. In recent decades Colorado Pikeminnow population abundance has declined, primarily as a result of predation by warmwater nonnative fish and habitat modification following dam construction. Small, reproducing populations remain in the Green and upper Colorado rivers, but their current population trajectory is declining and the San Juan River population is maintained primarily through stocking. As such, establishment of an additional population could aid recovery efforts and increase the species' resilience and population redundancy. The Colorado River in Grand Canyon once supported Colorado Pikeminnow, but until recently habitat suitability in this altered reach was considered low as a result of depressed thermal regime and abundant nonnative predators. Climate change and ongoing drought has presented an opportunity to evaluate the feasibility of native fish restoration in a system where declining reservoir storage has led to warmer releases and re-emergence of riverine habitat. These changes in the physical attributes of the river have occurred in concert with a system-wide decline in nonnative predators. Conditions 10 y ago were not compatible with reintroduction feasibility in Grand Canyon; however, as a result of rapidly changing conditions an expert Science Panel was convened to evaluate whether the physical and biological attributes of this reach could now support various life stages of Colorado Pikeminnow. Here, we report on the evaluation process and outcome from the Science Panel, which developed a science-based recommendation to the U.S. Fish and Wildlife Service on reintroduction feasibility. The Science Panel concluded that current habitat attributes in Grand Canyon could satisfy some, but perhaps not all, Colorado Pikeminnow life history requirements. This reach has the potential to support adult and subadult growth, foraging, migrations, and spawning, but low juvenile survival may limit recruitment. However, populations of other native species are successfully reproducing and increasing in western Grand Canyon, even in areas once considered suboptimal habitat. Should managers decide to move to the next phase of this process, actions such as experimental stocking and monitoring, telemetry studies, bioenergetics modeling, and laboratory-based research may provide additional information to further evaluate a potential reintroduction effort in this rapidly changing but highly altered system.

The Evolution of FinTech in Scientific Research: A Bibliometric Analysis

This study aims to investigate how FinTech evolved over time in research using bibliometric analysis. First, 1359 publications particularly related to the field of FinTech, from 2010 to 2021, were collected from the Scopus database. This study analyzed the fundamental issues and characteristics of FinTech in research, such as the annual contribution of publication, hot in the press, and foci, using theme analysis, concurrence analysis, and timeline analysis of authors’ keywords. Second, prolific objects, such as journals, authors, institutions, countries, regions, and corresponding pivotal cooperative relationship mapping were used to present who leads considerable attention in FinTech research. Third, the citation structures of authors and journals were investigated, and presented the burst detection analysis of cited authors, journals, and references. Finally, combining the analysis results with the current financial environment, the challenges and future development opportunities are discussed further. This bibliometric analysis revealed an increasing annual publication trend, a shifting focus on financial inclusion, a dominance of authors from the USA, and a growing number of international collaborations and publications from different sources, indicating FinTech as a lively field with potential for further scientific enrichment. Accordingly, this comprehensive study of the FinTech documents not only reviews the current research characteristics and trajectories, but also helps scholars find the appropriate research entry-point and conduct in-depth research.

Circuit Breaker Fault Diagnosis Method Based on Coil Current Time Sequence Phase Trajectory Characteristics

The traditional circuit breaker fault diagnosis method suffers from insufficient feature information extraction and is easily affected by abnormal signal acquisition. To address this, this paper introduces the phase space reconstruction algorithm to reconstruct the current signal for fault diagnosis based on phase trajectory features. The proposed method uses a first-order forward differencing method and mutual information method to process abnormal data and select the parameters of the reconstruction, then extract overall and local inflection point features to construct a fault feature set. The support vector machine algorithm-based model is trained and tested using actual samples, and the results show that the proposed method can adaptively sample anomalous signals, exhibit strong robustness, and significantly improve the accuracy of fault classification.

Staying in bounds: A framework for setting workplace boundaries to promote physician wellness.

Staying in bounds: A framework for setting workplace boundaries to promote physician wellness.

Suppression of dc‐offset current in ac‐link of dual‐active‐bridge dc‐dc converter based on triple‐phase‐shift optimal control

AbstractWhen dual‐active‐bridge dc‐dc converter (DAB) with energy storage load operates in a wide voltage range and high dynamic condition, the mismatch of primary and secondary side voltages will lead to high current stress and loss, and the dc‐offset current in the high‐frequency ac link will lead to magnetic saturation of magnetic components, which will damage the devices in serious cases. Therefore, aiming at the operation of DAB in a wide voltage range, a triple‐phase‐shift (TPS) optimal control strategy is adopted, and the phase shift angles of the bridges are adjusted according to the voltage ratio, so as to optimize the electrical stress and loss. What is more, the cause and mechanism of dc‐offset current in the ac‐link are analysed. Based on the TPS optimal strategy, the static dc‐offset current is suppressed with the low‐bandwidth detection of the offset current and the dynamic dc‐offset current is suppressed with the planning the current trajectory. A small‐power prototype is built, and the effectiveness of the TPS optimal control and the static and dynamic dc‐offset current suppression is verified.

Adaptive Model Predictive Current Control for PMLSM Drive System

This article proposes an adaptive model predictive current control (AM-MPCC) for surface-mounted permanent magnet linear synchronous motor systems to simultaneously enhance the robustness against permanent magnet flux, inductance, and resistance mismatches. First, the conventional continuous control set model predictive control is analyzed, illustrating that parameter variations will inevitably deteriorate the current regulation performance. Then, an adaptive predictive model, which involves a disturbance term and an optimized current change rate coefficient, is proposed. The optimal coefficient is estimated using a steady-state incremental model and the steepest descent method at each control period. A discrete-time sliding mode disturbance observer is devised based on the adaptive model with updated coefficients to achieve the disturbance term. Finally, an exponential reaching law-based-reference trajectory is defined for the cost function of AM-MPCC to adjust the current approach trajectory. Experimental results verify the excellent robustness performances of the proposed method.

Special Issue: Climate Crisis and Primary Health Care.

In September 2021, Family Practice joined with over 200 medical journals publishing a joint editorial which called climate change “the greatest threat to public health.”1 In 2023, we have decided that it is time to do more. As far as we know this is the first ever special edition on Climate Crisis in a Family Medicine journal: however given current trajectories for planetary warming, it is unlikely to be the last. Primary care clinicians working in 2023 are on the frontline, dealing with the healthcare impacts of record-breaking flooding, wildfires, and heatwaves. The physical and mental health impacts of Australian bushfires are explored in this issue in both older adults2 and new mothers3 with an emphasis on learnings and opportunities for primary care. The climate crisis has specific impacts on rural communities that are explored in an international review which also outlines key issues for healthcare utilization.4 Further, the disproportionate impact of the climate crisis for socioeconomically ­disadvantaged groups is explored by Blane et al.5 and medical-legal partnerships are highlighted by Anderson et al. for their role in mitigating climate impacts in disadvantaged populations.6

Multi‐decadal stability of fish productivity despite increasing coral reef degradation

Abstract Under current trajectories, it is unlikely that the coral reefs of the future will resemble those of the past. As multiple stressors, such as climate change and coastal development, continue to impact coral reefs, understanding the changes in ecosystem functioning is imperative to protect key ecosystem services. We used a 26‐year dataset of benthic reef fishes (including cryptobenthic fishes) to identify multi‐decadal trends in fish biomass production on a degraded coral reef. We converted fish abundances into estimates of community productivity to track the long‐term trend of fish biomass production through time. Following the first mass coral bleaching event in 1998, the abundance, standing biomass and productivity of fish communities remained remarkably constant through time, despite the occurrence of multiple stressors, including extreme sedimentation, cyclones and mass coral bleaching events. Species richness declined following the 1998 bleaching event, but rebounded to prebleaching levels and also remained relatively stable. Although the species composition of the communities changed over time, these new community configurations still maintain a steady level of fish biomass production. While these highly dynamic and increasingly degraded systems can still provide some critical ecosystem functions, it is unclear whether these patterns will remain stable over future decades. Read the free Plain Language Summary for this article on the Journal blog.

Проблемы и возможности развития моногородов российской Арктики

Broad context of the dynamics and prospects of Russian Arctic development within the framework of achieving its strategic objectives indicates the magnitude of the tasks, the solution of which consists in the actualization of, firstly, the risks and opportunities for environmental and social responsibility of vertically integrated companies, whose production branches conduct their activities in the Arctic, and, secondly, the supportive role of the state as the regulator of conditions for the development of business initiatives. The aims of the study are to identify significant factors that influence the dynamics of socio-economic development and to determine the prospects for the development of single-industry towns in the Russian Arctic. Research methods include bibliographical, comparative, economic and statistical analysis. The study substantiates the critical factors limiting the development opportunities of single-industry towns in the Russian Arctic. The first group is represented by the state of mineral resource base, which determines natural limits and cyclicality of production activities of city-forming enterprises. The second group is the global crisis phenomena, producing the dependence of production of city-forming enterprises on the external conjuncture of prices for raw materials and main export items. The third group includes risks of fulfilment of budgetary obligations. Taken together, these factors limit the opportunities for economic diversification of single-industry towns in the Russian Arctic and the development of entrepreneurial activity there. It has been revealed that the promising opportunities for the development of single-industry towns in the Russian Arctic are limited by the priority areas of investment activities of vertically integrated companies and imperfect state instruments of development support. The practical significance of the study is determined by the current trajectory of territorial development within the framework of the global strategy for sustainable development of extractive industries of a city-forming nature that takes into account not only risks, but also opportunities.

“New Wine in Old Bottles”: Structures of Feeling for a New Way to See New Wood Products

Acknowledging an undeniable need for innovation, this paper offers a qualitative assessment for recognition and policy advocacy for superior innovations—for new wood products and processes offering more benefits and fewer drawbacks than other innovations. The paper highlights the irrationality of using the limited natural and human-made goods of the world to produce and consume inferior innovations, especially when they fail to mitigate or, in fact, contribute to worsening climate change. Raymond Williams’ “structures of feeling” are used to disclose evaluative commitments associated with the “new” characteristic of industrialized and indigenous civilizations toward illuminating potential pathways for halting an otherwise seemingly unstoppable engine of climate change from pushing all of life on Earth over its precipice. Discussing how the “new” is always implicated in the “old,” decision-making and design methods applicable over the whole of the value chain are proposed for generating “new” innovations and processes that are genuinely able to change the current world trajectory of our species. Future research is also discussed.