Physical Connection Research Articles

Integrating Electric Vehicles to Power Grids: A Review on Modeling, Regulation, and Market Operation

Fossil energy consumption and environmental protection issues have pushed electric vehicles (EVs) to become one of the alternatives to traditional fossil-fuel vehicles. EV refers to a vehicle that uses electric energy as power and is driven by an electric motor. The electric energy of EVs is stored in batteries. When the EV is not traveling, the battery can provide power for other loads. Therefore, with the increase in the number of EVs and the load of the power grid, the EV-to-grid (V2G) mode, which uses EVs to supply power to the power grid, has gradually entered the field of vision of researchers. The physical connection mode, charge and discharge technology, and energy management strategy are the main topics of the current review papers; however, there is a lack of systematic research on V2G modeling, framework, and business models. This paper describes the concepts of the spatio-temporal distribution model and the adjustable capacity of EVs. In addition, common constraints and methods in optimization are introduced. Moreover, this paper introduces the interactive relationship among power grids, load aggregators, and EV users. Furthermore, the business model of V2G is introduced and analyzed from various perspectives. Finally, the future development of V2G is pointed out. This paper’s goal is to provide an overview of the present V2G application scenarios and to identify any challenges that must be overcome.

Different higher order kinematics between star-forming and quiescent galaxies based on the SAMI, MAGPI, and LEGA-C surveys

ABSTRACT We present the first statistical study of spatially integrated non-Gaussian stellar kinematics spanning 7 Gyr in cosmic time. We use deep, rest-frame optical spectroscopy of massive galaxies (stellar mass $M_\star \gt 10^{10.5} \, \mathrm{M_\odot }$) at redshifts z = 0.05, 0.3, and 0.8 from the SAMI, MAGPI, and LEGA-C surveys, to measure the excess kurtosis h4 of the stellar velocity distribution, the latter parametrized as a Gauss–Hermite series. We find that at all redshifts where we have large enough samples, h4 anticorrelates with the ratio between rotation and dispersion, highlighting the physical connection between these two kinematic observables. In addition, and independently from the anticorrelation with rotation-to-dispersion ratio, we also find a correlation between h4 and M⋆, potentially connected to the assembly history of galaxies. In contrast, after controlling for mass, we find no evidence of independent correlation between h4 and aperture velocity dispersion or galaxy size. These results hold for both star-forming and quiescent galaxies. For quiescent galaxies, h4 also correlates with projected shape, even after controlling for the rotation-to-dispersion ratio. At any given redshift, star-forming galaxies have lower h4 compared to quiescent galaxies, highlighting the link between kinematic structure and star-forming activity.

ON SOME APPLICATIONS OF THE FORMULA OF THE CENTER OF MASS

From the point of view of didactics, the use of intersubject links to some extent raises the scientific level of teaching, promotes easy assimilation of the presented material. It is no secret that mathematics plays a "dictating" role in this connection, contributing to the substantiation of various physical phenomena and regularities. Despite this "dictating" circumstance, the interdisciplinary connection of mathematics and physics has a dual nature. On the one hand, mathematical knowledge is used to study physical problems and questions, on the other hand, there is a feedback loop when physical regularities fill the field of application of mathematical knowledge, making the teaching of mathematical "abstract" material more objective and interesting. The article is devoted to the identification of some possible useful applications of physical "tools" in the process of teaching mathematical material. In particular, on the basis of the vector formula for determining the radius-vector of the center of mass, well-known from the physics school program, the work offers an innovative-physical approach to solving the problems of covering areas encountered in combinatorics, which is the scientific and pedagogical novelty of the work. Considering such tasks, in the article we will first briefly outline their traditional-mathematical solutions, after which we will offer innovative-physical solutions using the formula for determining the center of mass of the body, thus revealing one more manifestation of the inverse intersubjective connection between physics and mathematics.

Patients' perspectives on video consultation for non-communicable diseases: a qualitative study in Singapore.

The COVID-19 pandemic increased the use of telemedicine in primary care services. Understanding patients' perspectives on telemedicine is pivotal for its wider adoption in managing non-communicable diseases (NCDs) in the community. To explore the views and concerns of patients who have yet to use video consultation (VC) for NCD management in Singapore. This qualitative study was conducted in a primary care clinic in Singapore. In total, 16 patients participated in individual in-depth interviews. The participants had type 2 diabetes mellitus and/or hypertension and/or hyperlipidaemia without prior VC experience. They were purposively enrolled in the polyclinic. Audited transcripts were independently coded by two investigators. Thematic analysis was performed to identify perspectives on telemedicine based on the health, information, and technology zones of the Health Information Technology Acceptance Model. The following three themes emerged: perceived benefits of VC utility; perceived barriers of VC adoption; and potential challenges of VC. Participants viewed VC as safe and convenient if they had stable NCD. They voiced concerns on possible suboptimal care owing to the absence of physical examination, network connectivity, and personal medical data security. Participants highlighted challenges of VC uptake such as digital health familiarity, availability of their own mobile and telemonitoring devices, and healthcare costs consideration. Addressing the concerns and challenges highlighted by non-VC users can help physicians and policymakers explore ways to scale up telemedicine in Singapore. A hybrid clinical care model comprising in-person visits and VC may be the way forward for NCD management.

A Novel Conditional Connectivity and Hamiltonian Connectivity of BCube with Various Faulty Elements

BCube is one of the main data center networks because it has many attractive features. In practical applications, the failure of components or physical connections is inevitable. In data center networks in particular, switch failures are unavoidable. Fault-tolerance capability is one main aspect to measure the performance of data center networks. Connectivity, fault tolerance Hamiltonian connectivity, and fault tolerance Hamiltonicity are important parameters that assess the fault tolerance of networks. In general, the distribution of fault elements is scattered, and it is necessary to consider the distribution of fault elements in different dimensions. We research the fault tolerance of BCube when considering faulty switches and faulty links/edges that distribute in different dimensions. We also investigate the connectivity, fault tolerance Hamiltonian connectivity, and Hamiltonicity. This study better evaluates the fault-tolerant performance of data center networks.

The Intermediate Connection of Subcells in Si-based Tandem Solar Cells.

Tandem solar cells are rationally designed and fabricated by stacking multiple subcells to achieve power conversion efficiency well above the Shockley-Queisser (SQ) limit. There is a large selection pool for the subcell candidates, such as Si, III-V, Kesterite, Perovskite, and organic solar cells. A series of different combinations of these subcells have been successfully demonstrated in practical tandem solar cell devices. However, there has not been a systematic summary of how to connect subcells in a tandem solar cell using a practical, cost-effective, and efficiency-beneficial fashion. In this work, the connection manners of subcells within a tandem cell are classified into three main categories, performing sequential growth, using the physical connection, and applying an intermediate layer, focusing on systematical description of intermediate layers using different materials. The advantages and disadvantages of these connection methods and their applicability to tandem cell types are further elaborated using two typical example models, III-V/Si and Perovskite inclusive tandem cell devices. Eventually, this work can provide useful guidance on how to carry out a suitable intermediate connection in the design of tandem solar cells depending on the selected subcells and device structure.

Influence of Physically Constrained Initial Perturbations on the Predictability of Mei-Yu Heavy Precipitation

Abstract Based on the conditional nonlinear optimal perturbation (CNOP) approach, the predictability of mei-yu heavy precipitation and its underlying physical processes is investigated. As an extension of our previous work, the practical predictability of heavy precipitation events is studied using more realistic initial perturbations than previously considered. The initial perturbation reflects certain physical connections among multiple variables, including zonal and meridional winds, potential temperature (T), and water vapor mixing ratio (Q). Two types of initial perturbations for the CNOP are identified, with similar spatial distributions but opposite signs and resulting effects. The accumulated precipitation is strengthened with mostly positive perturbations in the T and Q components for the CNOP and weakened by negative perturbations. Comparing downscaling (DOWN) perturbations and random perturbations (RPs) with the CNOP, it is found that the CNOP and DOWN perturbations exhibit particularly large- and mesoscale spatial structures, respectively, while the RPs yield a spatial distribution with mostly convective-scale features. Also, the CNOP results in the largest error growth and forecast uncertainty, especially for Q, followed by the DOWN perturbations; those in the RPs are the smallest. These results provide important implications for optimizing the initial perturbations of convection-permitting ensemble prediction systems, especially precipitation forecasts. Moreover, it is suggested that small-scale related variables, that is, those associated with vertical motion and microphysical processes, are much less predictable than thermodynamic variables, and the errors grow through distinct physical processes for the three types of initial perturbations, that is, those with flow-dependent features.

Research on the Current Situation and Countermeasures of Life Education for Chinese Primary School Students

In recent years, various problems in life education for primary school students have become increasingly prominent. There have been a number of tragic events involving minors that could have been prevented were students more aware of themselves and their physical and psychological connection to society as a whole and therefore other lives around them. This paper mainly discusses the life education of primary school students, which is of great significance for their physical and mental growth and overall development. For the purpose of this research, the author has used a literature analysis method and has drawn on previously published work to aid in the research for this paper. The author has discovered some problems through this research. The educational methods and environment of many families are not conducive to the development of life education. Schools do not pay enough attention to life education and lack resources. Poor social values in society and adverse factors in the network have a negative impact on life education for primary school students. The author also has put forward some suggestions. It is necessary to enhance the awareness of life education among educational subjects and create a good environment for life education. At the same time, it is also necessary to expand the content and form of life education, strengthen the training of teachers, and establish a complete teaching evaluation system.

Simulation and comparative study of the effect of the electrical connection between the battery electrodes on the battery thermal behavior

Accurately simulating and characterizing the thermal behavior of lithium batteries is vital for thermal design and management. Currently, the widely used simulation method for studying battery module thermal behavior and management is the virtual electrical connection. However, this method overlooks the presence of the busbar. Therefore, this study utilizes a physical electrical connection simulation method to investigate the impact of busbar heat generation and transfer on the thermoelectric behavior of the battery module. The results indicate that the busbar's heat production and transfer significantly affect the current density and temperature distribution, as well as the temperature uniformity of the battery module. The physical electrical connection simulation method accurately models the actual current transfer process between the battery electrodes, aligning with the real-world operation. In comparison to the virtual electrical connection simulation method, the physical electrical connection approach shows elevated local temperatures at the battery electrodes and the upper area in proximity to the busbar. It also exhibits more significant temperature gradients and worse temperature uniformity. Under real-world driving conditions, the temperature and heat generation of the battery undergo more frequent and wider fluctuations compared with constant-current discharge. The impact of the busbar's heat production and transfer on battery thermal behavior becomes more evident in these conditions. For example, under the FTP75, NEDC, and WLTC conditions, the maximum temperature increased by 8.04 °C, 28.43 °C, and 27.35 °C respectively, and the maximum temperature difference increased by 7.91 °C, 28.41 °C, and 27.19 °C respectively. Thus, the physical electrical connection simulation method significantly enhances the realism of battery module thermoelectric behavior simulations, contributing to the accuracy and effectiveness of thermal management analysis and product design.

Analysis and Experiment of Laser Energy Distribution of Laser Wireless Power Transmission Based on a Powersphere Receiver

Laser wireless power transmission (WPT) is one of the most important technologies in the field of long-range power transfer. This technique uses a laser as a transmission medium instead of conventional physical or electrical connections to perform WPT. It has the characteristics of long transmission distance and flexible operation. The existing laser wireless power transmission system uses photovoltaic cells as a receiver, which convert light into electricity. Due to the contradiction between the Gaussian distribution of laser and the uniform illumination requirements of photovoltaic cells, the laser wireless power transmission technology has problems such as low transmission efficiency and small output power. Therefore, understanding the energy distribution changes in the laser during transmission, especially the energy change after the laser is transmitted to each key device, and analyzing the influencing factors of the energy distribution state, are of great significance in improving the transmission efficiency and reducing the energy loss in the system. This article utilizes the optical software Lighttools as a tool to establish a laser wireless power transmission model based on a powersphere. This model is used to study the energy distribution changes in the laser as it passes through various components, and to analyze the corresponding influencing factors. To further validate the simulation results, an experimental platform was constructed using a semiconductor laser, beam expander, Fresnel lens, and powersphere as components. A beam quality analyzer was used to measure and analyze the laser energy distribution of each component except for the powersphere. The output voltage and current values of various regions of the powersphere were measured using a multimeter. The energy distribution of the powersphere was reflected based on the linear relationship between photo-generated current, voltage, and light intensity. The experimental results obtained were in good agreement with the simulation results. Simulations and experiments have shown that using a beam expander can reduce divergence angle and energy loss, while employing large-aperture focusing lens can enhance energy collection and output power, providing a basis for improving the efficiency of laser wireless power transfer.

Connecting the mechanical properties of magnesium and high-entropy alloys

The deformation mechanisms in individual crystal structures have been extensively studied, such as the yielding phenomenon in face-centered-cubic (FCC) high-entropy alloys (HEAs) and the ductility in hexagonal close-packed (HCP) magnesium alloys. However, the physical connection of these mechanisms between the different crystal structures has rarely been investigated. For example, high-strength HEAs and ductile magnesium alloys both require low stacking fault energy (SFE), and the physical origin of this common feature is unclear. Here we provide a physical model for the SFE trend in FCC HEAs that connects the two phenomena. The physical model predicts the change of SFE based on elastic constants and geometrical parameters. This study paves the pathway to unifying the mechanics of close-packed materials.

The triple-dip La Niña of 2020–22: updates to the correlation of ENSO with the termination of solar cycles

The Sun provides the energy required to sustain life on Earth and drive our planet’s atmosphere. However, establishing a solid physical connection between solar and tropospheric variability has posed a considerable challenge across the spectrum of Earth-system science. Over the past few years a new picture to describe solar variability has developed, based on observing, understanding and tracing the progression, interaction and intrinsic variability of the magnetized activity bands that belong to the Sun’s 22-year magnetic activity cycle. A solar cycle’s fiducial clock does not run from the canonical min or max, instead resetting when all old cycle polarity magnetic flux is cancelled at the equator, an event dubbed the “termination” of that solar cycle, or terminator. In a recent paper, we demonstrated with high statistical significance, a correlation between the occurrence of termination of the last five solar cycles and the transition from El Niño to La Niña in the Pacific Ocean, and predicted that there would be a transition to La Niña in mid 2020. La Niña did indeed begin in mid-2020, and endured into 2023 as a rare “triple dip” event, but some of the solar predictions made did not occur until late 2021. This work examines what went right, what went wrong, the correlations between El Niño, La Niña and geomagnetic activity indices, and what might be expected for the general trends of large-scale global climate in the next decade.

Interactive Distribution Expansion and Measurement Planning Considering Controlled Partitioning

To model interactions among system expansion, con-trolled partitioning (CP), and observability, an integrated multi-period framework is developed in this paper for simultaneous planning of distribution systems and measurements with CP con-straints (DSMP-CP) in unbalanced multi-phase networks. The proposed framework, employing the network AC model, is formu-lated as a mixed-integer quadratically-constrained programing problem. This problem minimizes investment costs (including the costs of feeder reinforcement, distributed generation (DG) place-ment, and allocation of micro-phasor measurement units and their measuring channels) and operation costs (including the costs of DG operation, energy purchased from the upstream grid (UG), re-dispatching of DG and UG injections, and energy curtailment). A phase-based observability function is also introduced to ensure the observability of all phases of buses. Furthermore, the concept of zero-injection (ZI) property is proposed for ZI groups considering physical connections and mutual impedances among phases to en-hance observability efficiency and avoid suboptimal solutions. To enhance problem tractability and eliminate linearization errors, a duality-based solution approach is proposed employing an exact-ness loop with recursive re-linearization. The performance of the proposed framework is evaluated by testing it on the unbalanced IEEE 111-node and 256-node distribution test systems.

A Comprehensive Simulation of Solar Wind Formation from the Solar Interior: Significant Cross-field Energy Transport by Interchange Reconnection near the Sun

The physical connection between thermal convection in the solar interior and the solar wind remains unclear due to their significant scale separation. Using an extended version of the three-dimensional radiative magnetohydrodynamic code RAMENS, we perform the first comprehensive simulation of the solar wind formation, starting from the wave excitation and the small-scale dynamo below the photosphere. The simulation satisfies various observational constraints as a slow solar wind emanating from the coronal hole boundary. The magnetic energy is persistently released in the simulated corona, showing a hot upward flow at the interface between open and closed fields. To evaluate the energetic contributions from Alfvén wave and interchange reconnection, we develop a new method to quantify the cross-field energy transport in the simulated atmosphere. The measured energy transport from closed coronal loops to open field accounts for approximately half of the total. These findings suggest a significant role of the supergranular-scale interchange reconnection in solar wind formation.

Computational model of integrin adhesion elongation under an actin fiber.

Cells create physical connections with the extracellular environment through adhesions. Nascent adhesions form at the leading edge of migrating cells and either undergo cycles of disassembly and reassembly, or elongate and stabilize at the end of actin fibers. How adhesions assemble has been addressed in several studies, but the exact role of actin fibers in the elongation and stabilization of nascent adhesions remains largely elusive. To address this question, here we extended our computational model of adhesion assembly by incorporating an actin fiber that locally promotes integrin activation. The model revealed that an actin fiber promotes adhesion stabilization and elongation. Actomyosin contractility from the fiber also promotes adhesion stabilization and elongation, by strengthening integrin-ligand interactions, but only up to a force threshold. Above this force threshold, most integrin-ligand bonds fail, and the adhesion disassembles. In the absence of contraction, actin fibers still support adhesions stabilization. Collectively, our results provide a picture in which myosin activity is dispensable for adhesion stabilization and elongation under an actin fiber, offering a framework for interpreting several previous experimental observations.

A multidisciplinary detection system for cyber attacks on Powertrain Cyber Physical Systems

With the introduction of external connectivity to modern vehicles, both academic and industry security practitioners addressed the issues related to external communication interfaces exposing internal networks that are used to control the different vehicle’s systems. Despite these issues are considered having little-to-no impact on the functioning of the vehicle itself due to their demand of physical connection, with the advent of cellular connectivity proof-of-concept and demonstrations of remote takeover of the vehicle have been showcased, raising awareness about the risks related to the introduction of external connectivity on the vehicle system. All these remote attacks demonstrated by security researchers exploited several vulnerabilities to gain remote access to the Controller Area Network (CAN), one of the most deployed in-vehicle communication protocol. In these works, the authors demonstrate how to exploit the drive-by-wire features of modern vehicles to jeopardize people inside and outside the vehicle. To address this issue, several researchers designed algorithms to detect the injection of malicious CAN messages. However, these solutions are focused on the only CAN communication, without considering all the other subsystems that can be used by an attacker to hijack the vehicular system. Due to their high complexity, modern vehicle can be seen as Cyber–Physical Systems, in which the physical system (i.e. the mechanics of the vehicle) are controlled via software hosted on microcontrollers that communicate with each other via different communication protocols. Hence, to properly address the cybersecurity of a modern vehicle it is necessary to consider all the different aspects of the system, without focusing on a single one. In this work we investigate the capabilities of a multidisciplinary approach for anomaly detection based for securing the powertrain system of a generic vehicle. The experimental analysis presented in this paper is based on the model of a generic internal combustion engine and a speed controller, communicating via CAN. Four different detection methods from both control theory and computer security are tested against cyber attacks carried out from different contexts. Our threat model is composed by different attack scenarios representative of known cyber-attacks targeting modern vehicles. The experimental evaluation presented in this work highlights the strengths and weaknesses of each detection method against different attack scenarios carried out on the different components of our system. To the best of our knowledge, this is the first paper addressing the cyber security of the connected vehicle with a multidisciplinary approach.

Love Expressions in Children's Poems before and after 2000

This study explores the expressions of love in children's poems before and after the year 2000. Seeing the differences in the characteristics of the generation of children before and after 2000, this study aims to find out the children's love expressions to their parents through imagery used in poems as a reflection of Birrul Walidain. This research applies the technique analysis from Miles and Huberman, started with data reduction and presentation to finally come to one conclusion. Furthermore, the result of this research found that there is a distinction between love expressions in two different eras. During the era before 2000, the children expressed their gratitude primarily to their parents for their direct emotional bonding. Furthermore, during the era after 2000, the children tended to deliver their hope and pray for their parents, which portrays that the children missed the direct physical connection with their parents because there are almost no narratives that indicated the use of a physical indicator of imagery; however, they still expressed their loves by writing their wishes in their poems.

Self-Supervised Learning for Multilevel Skeleton-Based Forgery Detection via Temporal-Causal Consistency of Actions

Skeleton-based human action recognition and analysis have become increasingly attainable in many areas, such as security surveillance and anomaly detection. Given the prevalence of skeleton-based applications, tampering attacks on human skeletal features have emerged very recently. In particular, checking the temporal inconsistency and/or incoherence (TII) in the skeletal sequence of human action is a principle of forgery detection. To this end, we propose an approach to self-supervised learning of the temporal causality behind human action, which can effectively check TII in skeletal sequences. Especially, we design a multilevel skeleton-based forgery detection framework to recognize the forgery on frame level, clip level, and action level in terms of learning the corresponding temporal-causal skeleton representations for each level. Specifically, a hierarchical graph convolution network architecture is designed to learn low-level skeleton representations based on physical skeleton connections and high-level action representations based on temporal-causal dependencies for specific actions. Extensive experiments consistently show state-of-the-art results on multilevel forgery detection tasks and superior performance of our framework compared to current competing methods.

RF02 Using functional genomic techniques to help us understand the TYK2 pathway in psoriasis

Abstract Genetic screens have identified around 126 genetic signals associated with psoriasis through genome-wide association studies (GWAS) and rare variant analyses (Tsoi LC, Stuart PE, Tian C et al. Large scale meta-analysis characterizes genetic architecture for common psoriasis associated variants. Nat Commun 2017; 8:15382). The aim of this study was to use genome-editing techniques to investigate and validate the effect of a psoriasis-associated genetic signal on the expression of TYK2. GWAS have linked TYK2 to psoriasis susceptibility through the association of a protein-changing, exonic variant where TYK2 impairment confers protection against the development of psoriasis and other autoimmune diseases. The vast majority of disease risk-associated variants are found outside gene-coding regions. Functional experimental techniques may help characterize the effect of these variants on gene expression. The development of genome editing technology, clustered regularly interspaced short-palindromic repeat-Cas9 (CRISPR-Cas9), has made it possible to edit cell genomes. We used CRISPR-Cas9 to validate functionally the psoriasis-associated single nucleotide polymorphism (SNP) rs892085 on TYK2 expression in immortal T-cell lines. In-house data from our centre revealed the presence of long-range physical interactions between rs892085 and TYK2. We are the first to investigate functionally this signal and characterize this physical connection. We used CRISPR-Cas9 systems to both activate and inhibit the region around rs892085 and then measured the consequence of this through informative functional readouts using quantitative reverse transcription polymerase chain reaction. This revealed consistent alteration of TYK2 expression upon inhibition and activation of rs892085. This supports previous observations, where this regulatory region harbouring GWAS-implicated variation operates through direct long-distance contact. Previously, the closest or most biologically relevant gene was often assigned to a GWAS variant. We have shown that this is unreliable, with DNA regions looping over large distances to control genes. This work provides the first functional validation of the psoriasis-associated SNP rs892085. TYK2 is a recognized drug target with one therapy, deucravacitinib, approved by the US Food and Drug Administration. Drugs entering the clinical development stage that have used human genetic data to select drug targets may be more likely to succeed. This work demonstrates the potential complexity of how risk alleles may work to dysregulate TYK2 signalling in disease, with both gene function and expression increasing the risk of disease. Ultimately, genetic risk scores, incorporating functional evidence from studies like this, may be generated to predict how patients with different genetically perturbed biology pathways may respond to therapy.

Dynamic coupling across energy forms and hybrid simulation of the multi-energy system

A multi-energy (ME) system can coordinate local energy sources and users and optimize the supply of various energy forms, to maximize the comprehensive utilization efficiency of energy. As the scale of the multi-energy system becomes more extensive and the physical connections of different energy forms become diversified, the coupling of various forms of energy becomes closer. Such development has brought significant challenges to safe operations and effective regulation of the system and equipment. However, no efficient and easy-to-use dynamic simulation method is available for multi-energy systems. It has become an urgent problem how to fully use the existing rich models and algorithms of conventional energy systems to construct the dynamic simulations of multi-energy systems. Based on the multi-energy system’s structure, components, and model characteristics, this paper studies the mechanism of cross-energy-form dynamic coupling, proposes the critical techniques of multi-energy hybrid simulation and verifies the effectiveness and accuracy of the methods through case tests.