mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
Deep insight into the voltage amplification effect from ferroelectric negative capacitance

Dear editor,Power dissipation has become one of the most serious problems for nano-electronics.For conventional transistors,the operation voltage cannot be continuously reduced due to the fundamental limitation of subthreshold swing (SS) (60 mV/decade at room temperature).The voltage amplification (VA) induced by the negative capacitance (NC) effect of ferroelectric (FE) material provides a possible approach for FE-based transistors to achieve sub-60 SS characteristics.However,the physical origin of NC effect in FE-FET are still unclear and controversial.The traditional quasi-static NC theory considers that the NC can be derived from the negative curvature of energycharge relationship of ferroelectric,which is unstable for standalone FE capacitor and can be stabilized by connecting an appropriate positive capacitor to reach a capacitance matching condition for VA.Different with quasi-static NC theory,it has been recently presented that the NC effect can be modeled as a transient phenomenon caused by the FE polarization switching.In,we have demonstrated the first direct experimental observation of NC phenomenon in a standalone FE capacitor,verifying its dynamic behavior.It is shown that the time-induced polarization is the origin of NC phenomenon.Nevertheless,further study on the optimization of gate stack in FEFETs for achieving VA is still needed.
Autonomous driving:cognitive construction and situation understanding

Autonomous vehicle is a kind of typical complex artificial intelligence system.In current research of autonomous driving,the most widely adopted technique is to use a basic framework of serial information processing and computations,which consists of four modules:perception,planning,decision-making,and control.However,this framework based on data-driven computing performs low computational efficiency,poor environmental understanding and self-learning ability.A neglected problem has long been how to understand and process environmental perception data from the sensors referring to the cognitive psychology level of the human driving process.The key to solving this problem is to construct a computing model with selective attention and self-learning ability for autonomous driving,which is supposed to possess the mechanism of memorizing,inferring and experiential updating,enabling it to cope with traffic scenarios with high noise,dynamic,and randomness.In addition,for the process of understanding traffic scenes,the efficiency of event-related mechanism is more significant than single-attribute scenario perception data.Therefore,an effective self-driving method should not be confined to the traditional computing framework of ‘perception,planning,decision-making,and control’.It is necessary to explore a basic computing framework that conforms to human driver’s attention,reasoning,learning,and decision-making mechanism with regard to traffic scenarios and build an autonomous system inspired by biological intelligence.In this article,we review the basic methods and main progress in current data-driven autonomous driving technologies,deeply analyze the limitations and major problems faced by related algorithms.Then,combined with authors’ research,this study discusses how to implement a basic cognitive computing framework of self-driving with selective attention and an event-driven mechanism from the basic viewpoint of cognitive science.It further describes how to use multi-sensor and graph data with semantic information (such as traffic maps and a spatial correlation of events) to realize the associative representations of objects and drivable areas,as well as the intuitive reasoning method applied to understanding the situations in different traffic scenarios.The computing framework of autonomous driving based on a selective attention mechanism and intuitive reasoning discussed in this study can adapt to a more complex,open,and dynamic traffic environment.
Optimal Planning of AC-DC Hybrid Transmission and Distributed Energy Resource System: Review and Prospects

With the highly-extensive integration of distributed renewable energy resources (DER) into the grid, the power distribution system has changed greatly in the structure, function and operating characteristics. On this ground, An AC-DC hybrid DER system becomes necessary for effective management and control over DER. This paper first summarizes the physical characteristics and morphological evolution of AC-DC hybrid DER system. The impact of these new features on system configuration planning is analyzed with respect to its flexible networking, rich operation control modes, and tight sourcenetwork- load-storage coupling. Then, based on a review of the existing research, problems and technical difficulties are figured out in terms of converter modeling, steady-state analysis, power flow calculation, operating scenarios management, and optimization model solution. In light of the problems and difficulties, a framework for the configuration optimization of AC-DC hybrid DER systems is proposed. At last, the paper provides a prospect of key technologies from six aspects including morphology forecasting, coupling interaction analysis, uncertainty modeling, operation simulation, optimization model solving algorithm and comprehensive scheme evaluation.
Summary of Useful Concepts About the Coordination of Directional Overcurrent Protections

This paper summarizes some useful concepts about the coordination of directional overcurrent protections. The following key topics are described: the analysis of systems in a ring configuration and only one source of short-circuit currents; the impossibility of obtaining selectivity for all the possible system configurations with multiple sources; the need for inverse functions in order to obtain selectivity in systems with multiple sources; the coordination with protections for radial loads; the coordination between instantaneous and delayed functions; the considerations to select the pickup values; the influence of contributions from motors to short circuit currents; the transient configurations due to sequential trips at both line ends; the influence of dynamic behavior of overcurrent functions; the influence of stability constraints; other specific considerations for ground functions; some specific considerations for systems with distributed generation. A summary of these points and their effect on the coordination of directional overcurrent protections is not available in the current literature. This novel description should facilitate the inclusion of these key points in research and coordination studies related to these protective functions.
An Approach for Establishing a Common Grid Model for Flow-based Market Mechanism Simulations

The discussions on the development of an electricity market model for accommodating cross-border cooperation remains active in Europe. The main interest is the establishment of market couplings without curtailing the fair use of the scarce transmission capacity. However, it is difficult to gain mutual consensus on this subject because of the absence of convincing simulation results for the entire region. To achieve that, researchers need a common grid model (CGM) which is a simplified representation of the detailed transmission model which comprises aggregated buses and transmission lines. A CGM should sufficiently represent the inter-area power flow characteristics. Generally, it is difficult to establish a standard CGM that represents the actual transmission network with a sufficient degree of exactness because it requires knowledge on the details of the transmission network, which are undisclosed. This paper addresses the issue and reviews the existing approaches in transmission network approximation, and their shortcomings. Then, it proposes a new approach called the adaptive CGM approximation (ACA) for serving the purpose. The ACA is a datadriven approach, developed based on the direct current power flow theory. It is able to construct a CGM based on the published power flow data between the inter-connected market areas. This is done by solving the issue as a non-linear model fitting problem. The method is validated using three case studies.
Bidding Strategy of a Virtual Power Plant Considering Carbon-electricity Trading

Virtual power plant (VPP) aggregates large amounts of distributed energy and controllable loads. The comprehensive consideration of carbon emissions and electricity transactions has great significance in improving the VPP operation’s economic efficiency. In this paper, the bidding strategy of the VPP by considering the carbon-electricity integration trading in an auxiliary service (AS) market is studied. First of all, the basic structure and operating features of the VPP are briefly introduced. Then, the bidding strategy model of carbon-electricity integration trading in an auxiliary service market is proposed and the corresponding objective function and the constraint conditions are also analyzed. Furthermore, the GAMS solver is utilized to give the optimal solution of the bidding strategy model. Finally, the effectiveness of the bidding strategy of a VPP based on the consideration of carbon-electricity integration trading is verified through simulation cases.
Collaborative Planning of Distributed Wind Power Generation and Distribution Network with Large-scale Heat Pumps

With the advancement of clean heating projects and the integration of large-scale distributed heat pumps into rural distribution networks in northern China, power grid companies face tremendous pressure to invest in power grid upgrades, which bring opportunities for renewable power generation integration. The combination of heating by distributed renewable energy with the flexible operation of heat pumps is a feasible alternative for dealing with grid reinforcement challenges resulting from heating electrification. In this paper, a mathematical model of the collaborative planning of distributed wind power generation (DWPG) and distribution network with large-scale heat pumps is developed. In this model, the operational flexibility of the heat pump load is fully considered and the requirements of a comfortable indoor temperature are met. By applying this model, the goals of not only increasing the profit of DWPG but also reducing the cost of the power grid upgrade can be achieved.
Review of System Strength and Inertia Requirements for the National Electricity Market of Australia

Synchronous generators (SGs) are still making major contributions to the re-stabilization of a power system following voltage/frequency disturbances, attributed to their inherent capability of providing system strength and inertia. However, SGs powered by fossil fuels are operating to a lesser extent and scheduled for decommissioning in the National Electricity Market (NEM) of Australia due to the accelerating increase of low bidding priced asynchronous generation of wind and solar, which leads to the reduction and even in some cases, a shortage of system strength and inertia. This paper comprehensively reviews the requirements of system strength and inertia in the NEM from an operational security perspective. Australia is the first country that established the regulation rules of system strength and inertia to accommodate issues of an emerging high penetration level of non-synchronous renewable generation.
Digital Twin Framework and Its Application to Power Grid Online Analysis

Digital twin (DT) framework is introduced in the context of application for power grid online analysis. In the development process of a new power grid real-time online analysis system, an online analysis digital twin (OADT) has been implemented to realize the new online analysis architecture. The OADT approach is presented and its prominent features are discussed. The presentation, discussion, and performance testing are based on a large-scale grid network model (40K+ buses), exported directly from the EMS system of an actual power grid. A plan to apply the OADT approach to digitize power grid dispatching rules is also outlined.
Stochastic Dynamic Economic Dispatch of Wind-integrated Electricity and Natural Gas Systems Considering Security Risk Constraints

As the proportion of wind power generation increases in power systems, it is necessary to develop new ways for wind power accommodation and improve the existing power dispatch model. The power-to-gas technology, which offers a new approach to accommodate surplus wind power, is an excellent way to solve the former. Hence, this paper proposes to involve power-to-gas technology in the integrated electricity and natural gas systems (IEGSs). To solve the latter, on one hand, a new indicator, the scale factor of wind power integration, is introduced into the wind power stochastic model to better describe the uncertainty of grid-connected wind power; on the other hand, for quantizing and minimizing the impact of the uncertainties of wind power and system loads on system security, security risk constraints are established for the IEGS by the conditional value-at-risk method. By considering these two aspects, an MILP formulation of a security-risk based stochastic dynamic economic dispatch model for an IEGS is established, and GUROBI obtained from GAMS is used for the solution. Case studies are conducted on an IEGS consisting of a modified IEEE 39-bus system and the Belgium 20-node natural gas system to examine the effectiveness of the proposed dispatch model.
Key Technologies of Ultra-high Voltage Hybrid LCC-VSC MTDC Systems

The key technologies of ultra-high voltage hybrid LCC-VSC MTDC systems are investigated, focusing on the design of system configurations, converter topologies and the control and protection system. A double converter per pole of VSC connection is proposed along with the design of a 5000 MW VSC valve to develop a ± 800 kV/5000 MW large-capacity power transmission. The hybrid MMC topology capable of clearing the DC faults and the control strategy are developed to effectively improve the reliability in case of overhead line faults. The control and protection system of the LCC-VSC MTDC system is introduced to offer flexible operations under both normal and abnormal conditions, which includes voltage/current margin-based coordination, converter switch-in and switch-out, re-connection and drop-off of a third station. Simulations of an LCC-VSC MTDC system based on the LCC-VSC MTDC project are performed.
Optimal Scheduling for Combined District Heating and Power Systems Using Subsidy Strategies

The ongoing development of cogeneration technology has promoted public awareness on the integration of different types of energy systems. Integration of power and heating systems is the most common approach for energy transmission. The heat and power coupling of combined heat and power (CHP) units constrains the improvement of flexibility to accommodate more wind power, especially in winter. To address this problem, electrical boilers (EBs) are utilized as independent heat sources in one heat station to enhance their flexibility. This paper proposes a subsidy based bi-level optimal model. The objective of the upper problem is to minimize the operating cost, while the lower problem is to maximize the benefits of CHP and EBs based on the subsidy signals sent by the power system operator (PSO). The bi-level model is reformulated as a single -level linear problem by Karush Kuhn Turck (KKT) conditions and recast to a mix integer quadratic program using strong duality theory. Numerical results performed on an IEEE six-bus system with a eight-node district heating system validate the proposed model. The results demonstrate that the subsidy strategies can make the EB and CHP units operate according to the system operators’ preferences to accommodate more wind power.
Cyclophosphamide-induced reproductive toxicity: Beneficial effects of Helichrysum odoratissimum (Asteraceae) in male Wistar rats

Objective: Cyclophosphamide (CP) is commonly used to treat some cancers, but its clinical efficacy is also linked with testicular toxicity. We investigated the effects of aqueous extract (AE) and methanolic extract (ME) of Helichrysum odoratissimum for reducing CP-induced reproductive toxicity in male rats. Methods: In addition to a normal control (group 1), drugs or vehicles were administered orally to seven groups (n = 5) of rats that had already received 4-weeks of pre-treatment with CP (5 mg/[kg·d], per oral administration); group 2 received CP + distilled water (10 mL/[kg·d]); group 3 received CP + 5 %tween 80 (10 mL/[kg·d]); group 4 received CP + clomiphene citrate (0.25 mg/[kg·d]); groups 5 and 6 received CP + AE (50 and 100 mg/[kg·d]) and groups 7 and 8 received CP + ME (50 and 100 mg/[kg·d]). Animals were sacrificed on day 15, and body and sexual organ weights, sperm characteristics, testosterone level and testicular histology were evaluated. Results: The CP-treated group showed a significant reduction (P < 0.001) in the body and seminal vesicle weights, testosterone level, sperm count, sperm motility and sperm viability, but elevated (P < 0.001) sperm morphological abnormalities and testicular structure alterations, compared to the control group. Interestingly, these detrimental effects of CP were reversed by treatment with H. odoratissimum extracts. For instance, both extracts and all doses of H. odoratissimum significantly increased the sperm count (P < 0.001), sperm motility (AE, 50 mg/kg, P < 0.05; ME, 50 and 100 mg/kg, P < 0.05) and sperm viability (AE, 50 mg/kg, P < 0.001; ME, 50 and 100 mg/kg, P < 0.001) compared to the CP group. H. odoratissimum also improved plasmatic and intratesticular testosterone levels and prevented histological alterations of the testes. Conclusion: H. odoratissimum might be considered as an alternative drug to alleviate/prevent reproductive damage in cancer patients receiving CP chemotherapy.
High-extraction-efficiency,nanosecond bidirectional ring amplifier with twin pulses

The output performances of a bidirectional ring amplifier with twin pulses are demonstrated.Compared to the extraction efficiency of 32% for single-pulse injection,the extraction efficiency of stored energy for twin-pulse injection with bidirectional propagation is increased to 60%.The maximum output energies of the twin pulses are 347 mJ and 351 mJ,and the output energy of a single pulse is only 373 mJ under the same amplifier operating conditions.The experimental results show that the bidirectional ring amplifier with twin pulses can achieve a higher extraction efficiency of stored energy at a lower operating fluence,and has potential applications in high-power and high-energy laser facilities.
Wave Breaking in the Periodic Integrable Hunter-Saxton Equation with a Dispersive Term

Considered here is the periodic Cauchy problem for an integrable Hunter-Saxton equation with a dispersive term. Firstly, we derive a precise blow-up criterion of strong solutions to the equation. Secondly, sufficient conditions guaranteeing the development of breaking waves in finite time are demonstrated by applying some conservative quantities and the method of characteristics, respectively. Finally, the exact blow-up rate is determined.
Challenges of identifying putative planetary-origin meteorites of non-igneous material

This paper summarizes the challenges of identifying planetary-origin meteorites of non-igneous composition-particularly those of sedimentary origin. Evidence for putative sedimentary-origin (sed-type) meteorites and their potential parent bodies is reviewed, suggesting that the list of candidate parent bodies for sed-type meteorites includes, but is not limited to, Mars, Enceladus, Ganymede, Europa, Ceres, Vesta, and other hypothetical planets that existed between the orbits of Mars and Jupiter in the past. The extraterrestrial origin and probable parent body for sed-type meteorites should be assessed based on multiple lines of evidence, and not solely limited to tests of oxygen and noble gas isotopes, whose signatures may undergo terrestrial contamination and which may exhibit significant heterogeneity within both the Solar System and parent cosmic bodies. The observed fall of a cosmic body, evidence of hypervelocity fall, signs of impact, presence of fusion crust, melting, and/or shock deformation features in impactor fragments should be considered as priority signs of meteoritic origin.
Electrically driven uniaxial stress device for tuning in situ semiconductor quantum dot symmetry and exciton emission in cryostat

Uniaxial stress is a powerful tool for tuning exciton emitting wavelength, polarization, fine-structure splitting (FSS), and the symmetry of quantum dots (QDs). Here, we present a technique for applying uniaxial stress, which enables us in situ to tune exciton optical properties at low temperature down to 15 K with high tuning precision. The design and operation of the device are described in detail. This technique provides a simple and convenient approach to tune QD structural symmetry, exciton energy and biexciton binding energy. It can be utilized for generating entangled and indistinguishable photons. Moreover, this device can be employed for tuning optical properties of thin film materials at low temperature.
Room-temperature stable two-dimensional ferroelectric materials

Ferroelectric materials, with spontaneous electric polarization that can be reversed by an external electric field, have many technological applications, such as non-volatile memories, field-effect transistors, and sensors. Ferroelectric polarization originates from an asymmetric distribution of atoms in a material’s crystal structure, requiring the material to have two energetically degenerate ground state structures (two stable spontaneous polarization states) with inversion symmetry breaking[1]. Based on Landau-Ginzburg-Devonshire theory, a ferroelectric material below its transition temperature is described by a double well free energy (F) landscape as a function of the electric polarization (P)[2] as shown in Fig. 1. Thinfilm ferroelectrics have the advantage to significantly scale down the dimensions of the devices. Moreover, the voltage used to flip the electric polarization can be much lower, satisfying the requirement for low-power consumption devices. However, in conventional thin-film ferroelectrics, the arrangement of atoms produces charges on the material’s surface, generating a strong opposite depolarization field to suppress the polarization.
Construction of a One-Vector Multiplex CRISPR/Cas9 Editing System to Inhibit Nucleopolyhedrovirus Replication in Silkworms

Recently the developed single guide(sg)RNA-guided clustered regularly interspaced short palindromic repeats/associated protein 9 nuclease(CRISPR/Cas9) technology has opened a new avenue for antiviral therapy. The CRISPR/Cas9 system uniquely allows targeting of multiple genome sites simultaneously. However, there are relatively few applications of CRISPR/Cas9 multigene editing to target insect viruses. To address the need for sustained delivery of a multiplex CRISPR/ Cas9-based genome-editing vehicle against insect viruses, we developed a one-vector(pSL1180-Cas9-U6-sgRNA) system that expresses multiple sgRNA and Cas9 protein to excise Bombyx mori nucleopolyhedrovirus(BmNPV) in insect cells. We screened the immediate-early-1 gene(ie-1), the major envelope glycoprotein gene(gp64), and the late expression factor gene(lef-11), and identified multiple sgRNA editing sites through flow cytometry and viral DNA replication analysis. In addition, we constructed a multiplex editing vector(PSL1180-Cas9-sgIE1-sgLEF11-sgGP64, sgMultiple) to efficiently regulate multiplex gene-editing and inhibit BmNPV replication after viral infection. This is the first report of the application of a multiplex CRISPR/Cas9 system to inhibit insect virus replication. This multiplex system can significantly enhance the potential of CRISPR/Cas9-based multiplex genome engineering in insect virus.