A U-Shaped Network-Based Grid Tagging Model for Chinese Named Entity Recognition

Chinese named entity recognition(CNER)has received widespread attention as an important task of Chinese information extraction.Most previous research has focused on individually studying flat CNER,overlapped CNER,or discontinuous CNER.However,a unified CNER is often needed in real-world scenarios.Recent studies have shown that grid tagging-based methods based on character-pair relationship classification hold great potential for achieving unified NER.Nevertheless,how to enrich Chinese character-pair grid representations and capture deeper dependencies between character pairs to improve entity recognition performance remains an unresolved challenge.In this study,we enhance the character-pair grid representation by incorporating both local and global information.Significantly,we introduce a new approach by considering the character-pair grid representation matrix as a specialized image,converting the classification of character-pair relationships into a pixel-level semantic segmentation task.We devise a U-shaped network to extract multi-scale and deeper semantic information from the grid image,allowing for a more comprehensive understanding of associative features between character pairs.This approach leads to improved accuracy in predicting their relationships,ultimately enhancing entity recognition performance.We conducted experiments on two public CNER datasets in the biomedical domain,namely CMeEE-V2 and Diakg.The results demonstrate the effectiveness of our approach,which achieves F1-score improvements of 7.29 percentage points and 1.64 percentage points compared to the current state-of-the-art(SOTA)models,respectively.

Comparative analyses of mitogenomes in the social bees with insights into evolution of long inverted repeats in the Meliponini

The insect mitogenome is typically a compact circular molecule with highly conserved gene contents.Nonetheless,mitogenome structural variations have been reported in specific taxa,and gene rearrangements,usually the tRNAs,occur in different lineages.Because synapomorphies of mitogenome organizations can provide information for phylogenetic inferences,comparative analyses of mitogenomes have been given increasing attention.However,most studies use a very few species to represent the whole genus,tribe,family,or even order,overlooking potential variations at lower taxonomic levels,which might lead to some incorrect inferences.To provide new insights into mitogenome organizations and their implications for phylogenetic inference,this study conducted comparative analyses for mitogenomes of three social bee tribes(Meliponini,Bombini,and Apini)based on the phylogenetic framework with denser taxonomic sampling at the species and population levels.Comparative analyses revealed that mitogenomes of Apini and Bombini are the typical type,while those of Meliponini show diverse variations in mitogenome sizes and organizations.Large inverted repeats(IRs)cause significant gene rearrangements of protein coding genes(PCGs)and rRNAs in Indo-Malay/Australian stingless bee species.Molecular evolution analyses showed that the lineage with IRs have lower dN/dS ratios for PCGs than lineages without IRs,indicating potential effects of IRs on the evolution of mitochondrial genes.The finding of IRs and different patterns of gene rearrangements suggested that Meliponini is a hotspot in mitogenome evolution.Unlike conserved PCGs and rRNAs whose rearrangements were found only in the mentioned lineages within Meliponini,tRNA rearrangements are common across all three tribes of social bees,and are significant even at the species level,indicating that comprehensive sampling is needed to fully understand the patterns of tRNA rearrangements,and their implications for phylogenetic inference.

Control of GaN inverted pyramids growth on c-plane patterned sapphire substrates

Growth of gallium nitride(GaN)inverted pyramids on c-plane sapphire substrates is benefit for fabricating novel devices as it forms the semipolar facets.In this work,GaN inverted pyramids are directly grown on c-plane patterned sapphire substrates(PSS)by metal organic vapor phase epitaxy(MOVPE).The influences of growth conditions on the surface morphol-ogy are experimentally studied and explained by Wulff constructions.The competition of growth rate among{0001},{1011},and{1122}facets results in the various surface morphologies of GaN.A higher growth temperature of 985 ℃ and a lowerⅤ/Ⅲratio of 25 can expand the area of{}facets in GaN inverted pyramids.On the other hand,GaN inverted pyramids with almost pure{}facets are obtained by using a lower growth temperature of 930℃,a higherⅤ/Ⅲratio of 100,and PSS with pattern arrangement perpendicular to the substrate primary flat.

Efficient and Stable Inverted Perovskite Solar Modules Enabled by Solid-Liquid Two-Step Film Formation

A considerable efficiency gap exists between large-area perovskite solar modules and small-area perovskite solar cells.The control of forming uniform and large-area film and perovskite crystallization is still the main obstacle restricting the efficiency of PSMs.In this work,we adopted a solid-liquid two-step film formation technique,which involved the evaporation of a lead iodide film and blade coating of an organic ammonium halide solution to prepare perovskite films.This method possesses the advantages of integrating vapor deposition and solution methods,which could apply to substrates with different roughness and avoid using toxic solvents to achieve a more uniform,large-area perovskite film.Furthermore,modification of the NiO_(x)/perovskite buried interface and introduction of Urea additives were utilized to reduce interface recombination and regulate perovskite crystallization.As a result,a large-area perovskite film possessing larger grains,fewer pinholes,and reduced defects could be achieved.The inverted PSM with an active area of 61.56 cm^(2)(10×10 cm^(2)substrate)achieved a champion power conversion efficiency of 20.56%and significantly improved stability.This method suggests an innovative approach to resolving the uniformity issue associated with large-area film fabrication.

Reduced-Order Observer-Based LQR Controller Design for Rotary Inverted Pendulum

The Rotary Inverted Pendulum(RIP)is a widely used underactuated mechanical system in various applications such as bipedal robots and skyscraper stabilization where attitude control presents a significant challenge.Despite the implementation of various control strategies to maintain equilibrium,optimally tuning control gains to effectively mitigate uncertain nonlinearities in system dynamics remains elusive.Existing methods frequently rely on extensive experimental data or the designer’s expertise,presenting a notable drawback.This paper proposes a novel tracking control approach for RIP,utilizing a Linear Quadratic Regulator(LQR)in combination with a reduced-order observer.Initially,the RIP system is mathematically modeled using the Newton-Euler-Lagrange method.Subsequently,a composite controller is devised that integrates an LQR for generating nominal control signals and a reduced-order observer for reconstructing unmeasured states.This approach enhances the controller’s robustness by eliminating differential terms from the observer,thereby attenuating unknown disturbances.Thorough numerical simulations and experimental evaluations demonstrate the system’s capability to maintain balance below50Hz and achieve precise tracking below1.4 rad,validating the effectiveness of the proposed control scheme.

Intrinsic thermal stability of inverted perovskite solar cells based on electrochemical deposited PEDOT

Thermal stability of perovskite materials is an issue impairing the long-term operation of inverted perovskite solar cells(PSCs). Herein, the thermal attenuation mechanism of the MAPb I3films that deposited on two different hole transport layers(HTL), poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS) and poly(3,4-ethylenedioxythiophene)(PEDOT), is comprehensively studied by applying a heat treatment at 85℃. The thermal stress causes the mutual ions migration of I, Pb and Ag through the device, which leads to the thermal decomposition of perovskite to form Pb I2. Interestingly, we find that I ions tend to migrate more towards electron transport layer(ETL) during heating, which is different with the observation of I ions migration towards HTL when bias pressure is applied. Moreover, the use of electrochemical deposited PEDOT as HTL significantly decreases the defect density of MAPb I3films as compared to PEDOT:PSS supported one. The electrochemical deposition PEDOT has good carrier mobility and low acidity, which avoids the drawbacks of aqueous PEDOT:PSS. Accordingly, the inverted PSCs based on PEDOT show superior durability than that with PEDOT:PSS. Our results reveal detailed degradation routes of a new kind of inverted PSCs which can contribute to the understanding of the failure of thermal-aged inverted PSCs.

Effect of mold and core preheating temperature on corrosion resistance of casting Al-12Si alloy U-shaped cooling channel

Temperature has an important impact on the corrosion resistance of mold with cooling channels prepared by casting method.The effect of preheating temperature of the mold and the carbon fiber core on the roughness and corrosion resistance of U-shaped cooling channels made of Al-12Si alloy was examined in depth.The experimental results suggest that as the preheating temperature increased from 273 K to 573 K,the roughness of the inner wall of the cooling channel reduced from 96.6μm to 77.0μm.When the preheating temperature continued to increase to 723 K,the roughness increased to 85.3μm.The wetting between the Al melt and the carbon fiber will reduce micro bubbles and waves on the channel wall as the preheating temperature rises,thereby reducing the roughness.However,with the further increase of preheating temperature,it will increase the solidification time of the Al melt.At this time,the carbon fiber and Al melt will take more time to react,which increases the roughness of the channel wall to a certain extent.The results of exfoliation corrosion show that the larger roughness will aggravate exfoliation corrosion.The prolongation of high temperature reaction time between the carbon fiber and the Al melt will lead to the segregation of Si,which is easy to cause intergranular corrosion.Therefore,reasonable preheating temperature has an important impact on the roughness and corrosion resistance of U-shaped cooling channels.

Enhancing performance of inverted quantum-dot light-emitting diodes based on a solution-processed hole transport layer via ligand treatment

The performance of inverted quantum-dot light-emitting diodes(QLEDs)based on solution-processed hole transport layers(HTLs)has been limited by the solvent-induced damage to the quantum dot(QD)layer during the spin-coating of the HTL.The lack of compatibility between the HTL’s solvent and the QD layer results in an uneven surface,which negatively impacts the overall device performance.In this work,we develop a novel method to solve this problem by modifying the QD film with 1,8-diaminooctane to improve the resistance of the QD layer for the HTL’s solvent.The uniform QD layer leads the inverted red QLED device to achieve a low turn-on voltage of 1.8 V,a high maximum luminance of 105500 cd/m2,and a remarkable maximum external quantum efficiency of 13.34%.This approach releases the considerable potential of HTL materials selection and offers a promising avenue for the development of high-performance inverted QLEDs.

Inverted Modelling:An Effective Way to Support Motion Planning of Legged Mobile Robots

This paper presents an effective way to support motion planning of legged mobile robots—Inverted Modelling,based on the equivalent metamorphic mechanism concept.The difference from the previous research is that we herein invert the equivalent parallel mechanism.Assuming the leg mechanisms are hybrid links,the body of robot being considered as fixed platform,and ground as moving platform.The motion performance is transformed and measured in the body frame.Terrain and joint limits are used as input parameters to the model,resulting in the representation which is independent of terrains and particular poses in Inverted Modelling.Hence,it can universally be applied to any kind of legged robots as global motion performance framework.Several performance measurements using Inverted Modelling are presented and used in motion performance evaluation.According to the requirements of actual work like motion continuity and stability,motion planning of legged robot can be achieved using different measurements on different terrains.Two cases studies present the simulations of quadruped and hexapod robots walking on rugged roads.The results verify the correctness and effectiveness of the proposed method.

Ecofriendly Hydroxyalkyl Cellulose Additives for Efficient and Stable MAPbI_(3)-Based Inverted Perovskite Solar Cells

Perovskite solar cells(PSCs)have been demonstrated to be one of the most promising technologies in the field of renewable energy.However,the presence of the defects in the perovskite films greatly limits the efficiency and the stability of the PSCs.The additive engineering is one of the most effective approaches to overcome this problem.Most of the successful additives are extracted from the petroleum-based materials,while the research on the biomass-based additives is still lagging behind.In this paper,two ecofriendly hydroxyalkyl cellulose additives,i.e.,hydroxyethyl cellulose(HEC)and hydroxylpropyl cellulose(HPC),are investigated on the performance of the MAPbl_(3)-based inverted PSCs.Due to the strong interaction between the hydroxyl groups of the cellulose and the divalent cations of the perovskite,these additives enhance the crystal grain orientation and significantly repair the defects of the perovskite films.Working as the additives,these two cellulose derivatives show a strong passivation ability,which significantly reduces the trap density and improves the optoelectronic feature of the PSCs.Compared with the average power conversion efficiency(PCE)of the control device(19.19%),an enhancement of~10%is achieved after the addition of HEC.The optimized device(PCE=21.25%)with a long-term stability(10:80 h,PCE=20.93%)is achieved by the incorporation of the HEC additives into the precursor solution.It is the best performance among the PSCs with the cellulose additives up to now.This research provides a novel choice to develop a cost-effective and renewable additive for the PSCs with high efficiency and excellent long-term stability.

Non-Fullerene-Based Inverted Organic Photovoltaic Device with Long-Term Stability

In this work,we developed the PM6:Y6-based inverted structure organic photovoltaic(i-OPV)with improved power conversion efficiency(PCE)and long-term stability by resolving the origins of the performance deterioration.The deep defects between the metal oxide-based electron transport layer and bulk-heterojunction photoactive layer interface were responsible for suboptimal PCE and facilitated degradation of devices.While the density of deep traps is increased during the storage of i-OPV,the penetrative oxygen-containing defects additionally generated shallow traps below the band-edge of Y6,causing an additional loss in the open-circuit voltage.The suppression of interfacial defects by chemical modification effectively improved the PCE and long-term stability of i-OPV.The modified i-OPV(mi-OPV)achieved a PCE of 17.42%,which is the highest value among the reported PM6:Y6-based i-OPV devices.Moreover,long-term stability was significantly improved:~90%and~80%retention of its initial PCE after 1200 h of air storage and illumination,respectively.

Recent progress of inverted organic-inorganic halide perovskite solar cells

In recent years,inverted perovskite solar cells(IPSCs)have attracted significant attention due to their low-temperature and cost-effective fabrication processes,hysteresis-free properties,excellent stability,and wide application.The efficiency gap between IPSCs and regular structures has shrunk to less than 1%.Over the past few years,IPSC research has mainly focused on optimizing power conversion efficiency to accelerate the development of IPSCs.This review provides an overview of recent improvements in the efficiency of IPSCs,including interface engineering and novel film production techniques to overcome critical obstacles.Tandem and integrated applications of IPSCs are also summarized.Furthermore,prospects for further development of IPSCs are discussed,including the development of new materials,methods,and device structures for novel IPSCs to meet the requirements of commercialization.

High frequency doubling efficiency THz GaAs Schottky barrier diode based on inverted trapezoidal epitaxial cross-section structure

A high-performance terahertz Schottky barrier diode(SBD)with an inverted trapezoidal epitaxial cross-sectional structure featuring high varactor characteristics and reverse breakdown characteristics is reported in this paper.Inductively coupled plasma dry etching and dissolution wet etching are used to define the profile of the epitaxial layer,by which the voltage-dependent variation trend of the thickness of the metal-semiconductor contact depletion layer is modified.The simulation of the inverted trapezoidal epitaxial cross-section SBD is also conducted to explain the physical mechanism of the electric field and space charge region area.Compared with the normal structure,the grading coefficient M increases from 0.47 to 0.52,and the capacitance modulation ratio(C^(max)/C_(min))increases from 6.70 to 7.61.The inverted trapezoidal epitaxial cross-section structure is a promising approach to improve the variable-capacity ratio by eliminating the accumulation of charge at the Schottky electrode edge.A 190 GHz frequency doubler based on the inverted trapezoidal epitaxial cross-section SBD also shows a doubling efficiency of 35%compared to that 30%of a normal SBD.

Large gastric hamartomatous inverted polyp accompanied by advanced gastric cancer:A case report

BACKGROUND Gastric hamartomatous inverted polyps(GHIPs)are benign polyps of the gastric submucosal layer.Currently there are 52 reported cases in the English literature.According to a literature review,approximately 27%of GHIPs show a coexisting carcinoma.CASE SUMMARY A 66-year-old man was referred to our institution with ulcerative lesions detected on esophagogastroduodenoscopy(EGD)during a regular check-up.Other medical findings were nonspecific.The lesions had borderline histologic features that could not exclude malignancy and were followed up with three EGDs and biopsies at intervals of 3 mo.The latest biopsy was revealed as an adenocarcinoma.A total gastrectomy was performed to remove the tumor.The surgical specimen revealed a 6.9 cm×4.5 cm sized GHIP with a coexisting 1.6 cm sized well-differentiated adenocarcinoma which extended to the muscularis propria.The malignancy did not originate from the GHIP but showed an overlap.CONCLUSION A large GHIP,which was unusually presented as an ulcerative lesion,was surgically removed,and was accompanied by advanced gastric cancer.Regular follow-up and thorough examinations of ulcerative lesions with equivocal biopsy have resulted in appropriate diagnosis and treatment.Therefore,aggressive intervention may be beneficial if GHIP is suspected.

Thermally Evaporated ZnSe for Efficient and Stable Regular/Inverted Perovskite Solar Cells by Enhanced Electron Extraction

Electron transport layers(ETLs)are crucial for achieving efficient and stable planar perovskite solar cells(PSCs).Reports on versatile inorganic ETLs using a simple film fabrication method and applicability for both low-cost planar regular and inverted PSCs with excellent efficiencies(>22%)and high stability are very limited.Herein,we employ a novel inorganic ZnSe as ETL for both regular and inverted PSCs to improve the efficiency and stability using a simple thermal evaporation method.The TiO_(2)-ZnSe-FAPbl_(3)heterojunction could be formed,resulting in an improved charge collection and a decreased carrier recombination further proved through theoretical calculations.The optimized regular PSCs based on TiO_(2)/ZnSe have achieved 23.25%efficiency with negligible hysteresis.In addition,the ZnSe ETL can also effectively replace the unstable bathocuproine(BCP)in inverted PSCs.Consequently,the ZnSe-based inverted device realizes a champion efficiency of 22.54%.Moreover,the regular device comprising the TiO_(2)/ZnSe layers retains 92%of its initial PCE after 10:00 h under 1 Sun continuous illumination and the inverted device comprising the C_(60)/ZnSe layers maintains over 85%of its initial PCE at 85℃for 10:00 h.This highlights one of the best results among universal ETLs in both regular and inverted perovskite photovoltaics.

Hole‑Transport Management Enables 23%‑Efficient and Stable Inverted Perovskite Solar Cells with 84%Fill Factor

NiO_(x)-based inverted perovskite solar cells(PSCs)havepresented great potential toward low-cost,highly efficient and stablenext-generation photovoltaics.However,the presence of energy-levelmismatch and contact-interface defects between hole-selective contacts(HSCs)and perovskite-active layer(PAL)still limits device efficiencyimprovement.Here,we report a graded configuration based on bothinterface-cascaded structures and p-type molecule-doped compositeswith two-/three-dimensional formamidinium-based triple-halideperovskites.We find that the interface defects-induced non-radiativerecombination presented at HSCs/PAL interfaces is remarkably suppressedbecause of efficient hole extraction and transport.Moreover,astrong chemical interaction,halogen bonding and coordination bondingare found in the molecule-doped perovskite composites,whichsignificantly suppress the formation of halide vacancy and parasitic metallic lead.As a result,NiO_(x)-based inverted PSCs present a power-conversion-efficiency over 23%with a high fill factor of 0.84 and open-circuit voltage of 1.162 V,which are comparable to the best reported around 1.56-electron volt bandgap perovskites.Furthermore,devices with encapsulation present high operational stability over 1,200 h during T_(90) lifetime measurement(the time as a function of PCE decreases to 90%of its initial value)under 1-sun illumination in ambient-air conditions.

Project-Based Teaching in Control Theory Education Based on V-REP: A Cart Inverted Pendulum Case

This paper provides a teaching concept for control theory education based on Virtual Robot Experimentation Platform(V-REP).A cart inverted pendulum virtual physical model is developed on V-REP.Students must analyze,design,and implement a suitable controller for the cart inverted pendulum system using their knowledge of the control theory.Different from traditional experiment and numerical simulation,virtual experiment is safe and less constrained.Moreover,the experiment results are more intuitive and obvious.This study can improve students’interest in learning the control theory and help students understand the relevant content better.

Review of Fault-tolerant Control for Motor Inverter Failure with Operational Quality Considered

In recent years,motor drive systems have garnered increasing attention due to their high efficiency and superior control performance.This is especially apparent in aerospace,marine propulsion,and electric vehicles,where high performance,efficiency,and reliability are crucial.The ability of the drive system to maintain long-term fault-tolerant control(FTC)operation after a failure is essential.The likelihood of inverter failures surpasses that of other components in the drive system,highlighting its critical importance.Long-term FTC operation ensures the system retains its fundamental functions until safe repairs or replacements can be made.The focus of developing a FTC strategy has shifted from basic FTC operations to enhancing the post-fault quality to accommodate the realities of prolonged operation post-failure.This paper primarily investigates FTC strategies for inverter failures in various motor drive systems over the past decade.These strategies are categorized into three types based on post-fault operational quality:rescue,remedy,and reestablishment.The paper discusses each typical control strategy and its research focus,the strengths and weaknesses of various algorithms,and recent advancements in FTC.Finally,this review summarizes effective FTC techniques for inverter failures in motor drive systems and suggests directions for future research.

Review of Three-phase Soft Switching Inverters and Challenges for Motor Drives

For electric vehicles (EVs),it is necessary to improve endurance mileage by improving the efficiency.There exists a trend towards increasing the system voltage and switching frequency,contributing to improve charging speed and power density.However,this trend poses significant challenges for high-voltage and high-frequency motor controllers,which are plagued by increased switching losses and pronounced switching oscillations as consequences of hard switching.The deployment of soft switching technology presents a viable solution to mitigate these issues.This paper reviews the applications of soft switching technologies for three-phase inverters and classifies them based on distinct characteristics.For each type of inverter,the advantages and disadvantages are evaluated.Then,the paper introduces the research progress and control methods of soft switching inverters (SSIs).Moreover,it presents a comparative analysis among the conventional hard switching inverters (HSIs),an active clamping resonant DC link inverter (ACRDCLI) and an auxiliary resonant commuted pole inverter (ARCPI).Finally,the problems and prospects of soft switching technology applied to motor controllers for EVs are put forward.

Adaptive Predefined-Time Backstepping Control for Grid Connected Photovoltaic Inverter

The system performance of grid-connected photovoltaic(PV)has a serious impact on the grid stability.To improve the control performance and shorten the convergence time,a predefined-time controller based on backstepping technology and dynamic surface control is formulated for the inverter in the grid-connected photovoltaic.The time-varying tuning functions are introduced into state-tracking errors to realize the predefined-time control effect.To address the“computational explosion problem”in the design process of backstepping control,dynamic surface control is adopted to avoid the analytical calculations of virtual control.The disturbances of the PV system are estimated and compensated by adaptive laws.The control parameters are chosen and the global stability of the closed-loop is ensured by Lyapunov conditions.Simulation results confirm the effectiveness of the proposed controller and ensure the predefined time control in the photovoltaic inverter.