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维生素D治疗全面性发育迟缓患儿的临床疗效研究
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作者 牛国辉 谢加阳 +6 位作者 朱登纳 崔博 赵会玲 王明梅 冯欢欢 张萌萌 李停停 《中国全科医学》 CAS 北大核心 2025年第3期346-351,共6页
背景 除了某些有明确病因的代谢性疾病导致的全面性发育迟缓(GDD),康复治疗是GDD的主要治疗方式;维生素D通过影响神经营养因子在调节神经细胞的发育和分化方面发挥着重要的神经保护作用;但目前关于补充维生素D对GDD患儿临床疗效的研究... 背景 除了某些有明确病因的代谢性疾病导致的全面性发育迟缓(GDD),康复治疗是GDD的主要治疗方式;维生素D通过影响神经营养因子在调节神经细胞的发育和分化方面发挥着重要的神经保护作用;但目前关于补充维生素D对GDD患儿临床疗效的研究开展较少。目的 探讨补充不同剂量的维生素D对GDD患儿康复治疗的临床效果。方法 于2020年9月—2022年6月选取在郑州大学第三附属医院康复医学科首次住院就诊的120例GDD患儿为研究对象,采用随机区组化的方法将其分为常规组(38例)、400 U组(37例)和1 200 U组(35例)。常规组仅进行常规康复治疗;400 U组在常规康复治疗的基础上给予口服400 U/d维生素D;1 200 U组在常规康复训练的基础上给予口服1 200 U/d维生素D。收集3组患儿的性别、就诊年龄等基本资料;于入院时(治疗前)及第3个疗程末(治疗后)行血清25羟维生素D[25(OH)D]水平检测和Gesell发育量表评估[评估适应能力、大运动能力、精细运动能力、语言能力和社交能力5个能区的发育商(DQ)];记录发生在患儿住院期间不良事件的次数,并对上述资料进行分析比较。结果 3组患儿性别、居住地、出生季节、分娩方式、就诊年龄、出生体质量、出生胎龄、主要就诊原因比较,差异均无统计学意义(P>0.05)。治疗前,3组患儿25(OH)D水平、Gesell量表各能区DQ值比较,差异均无统计学意义(P>0.05);治疗后,1 200 U组患儿血25(OH)D水平、Gesell量表大运动能力、精细运动能力、语言能力DQ值高于常规组(P<0.05)。第1、2疗程期间,3组患儿不良事件发生率比较,差异无统计学意义(P>0.05);第3疗程期间,1 200 U组患儿不良事件发生率低于常规组及400 U组(P<0.05)。结论 补充1 200 U维生素D对GDD患儿的康复疗效有益,且能减少康复期间不良事件的发生率。 展开更多
关键词 儿童发育障碍 广泛性 全面性发育迟缓 维生素d Gesell量表 不良事件 康复治疗 神经保护
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绝经后女性维生素D水平与生殖特点和运动膳食情况的关系 被引量:1
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作者 王东阳 杨巧慧 林欣潮 《中国组织工程研究》 CAS 北大核心 2025年第5期1021-1025,共5页
背景:研究证明绝经后骨质疏松症与女性生殖特点和运动膳食有关,但是鲜有研究证明女性生殖特点及运动膳食是否对绝经后女性维生素D有影响。目的:探讨北京市绝经后女性维生素D水平与女性生殖特点和运动膳食情况的关系及其影响因素。方法:... 背景:研究证明绝经后骨质疏松症与女性生殖特点和运动膳食有关,但是鲜有研究证明女性生殖特点及运动膳食是否对绝经后女性维生素D有影响。目的:探讨北京市绝经后女性维生素D水平与女性生殖特点和运动膳食情况的关系及其影响因素。方法:选取2017年9月至2018年5月北京市多个城区的17个社区现场问卷调查的727例46-75岁绝经后女性作为研究对象,问卷内容包括受试者的基本信息和月经史、绝经史、妊娠史、运动膳食情况等。采用电化学发光免疫分析仪及其配套试剂测定25-(OH)D水平;使用双能X射线骨密度检测仪测定腰椎(L1-L4、整体)和双髋关节(股骨颈、整体)的骨密度和T值;观察维生素D与生殖特点和运动膳食的相关性,并进行维生素D的影响因素分析。结果与结论:①维生素D正常组136例(18.7%),维生素D不足组389例(53.5%),维生素D缺乏组202例(27.8%);平均维生素D水平为(15.60±5.85)ng/mL。②随着维生素D水平的升高,不同部位的骨密度值及T值也随之升高。③维生素D水平与初潮年龄、月经持续天数、绝经阶段、运动情况、饮食类型、饮食偏好均呈正相关(P<0.05);与月经周期、绝经年龄、生育次数均呈负相关(P<0.05);与初孕年龄、怀孕次数无相关性(P>0.05)。④多因素有序Logistic回归分析结果显示,喝奶制品频率对绝经后女性维生素D值存在正向相关(P<0.05),且奶制品是维生素D水平的保护因素。⑤调查结果说明,北京市绝经后女性维生素D水平普遍不足、骨密度值普遍低下,维生素D水平与部分生殖特点、运动膳食情况存在关联,且其中喝奶制品是其保护因素。因此可以通过开展相关骨质疏松的健康教育,对绝经后女性膳食情况进行调整加以干预,增加体内维生素D含量,以期增加骨密度值,减少绝经后骨质疏松患病率。 展开更多
关键词 北京市 绝经后女性 维生素d 生殖特点 运动膳食 骨质疏松
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Wedge-shaped HfO_(2) buffer layer-induced field-free spin-orbit torque switching of HfO_(2)/Pt/Co structure 被引量:1
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作者 陈建辉 梁梦凡 +4 位作者 宋衍 袁俊杰 张梦旸 骆泳铭 王宁宁 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期662-667,共6页
Field-free spin-orbit torque(SOT)switching of perpendicular magnetization is essential for future spintronic devices.This study demonstrates the field-free switching of perpendicular magnetization in an HfO_(2)/Pt/Co/... Field-free spin-orbit torque(SOT)switching of perpendicular magnetization is essential for future spintronic devices.This study demonstrates the field-free switching of perpendicular magnetization in an HfO_(2)/Pt/Co/TaO_(x) structure,which is facilitated by a wedge-shaped HfO_(2)buffer layer.The field-free switching ratio varies with HfO_(2)thickness,reaching optimal performance at 25 nm.This phenomenon is attributed to the lateral anisotropy gradient of the Co layer,which is induced by the wedge-shaped HfO_(2)buffer layer.The thickness gradient of HfO_(2)along the wedge creates a corresponding lateral anisotropy gradient in the Co layer,correlating with the switching ratio.These findings indicate that field-free SOT switching can be achieved through designing buffer layer,offering a novel approach to innovating spin-orbit device. 展开更多
关键词 spin-orbit torque field-free switching HfO_(2) buffer layer
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Control method based on DRFNN sliding mode for multifunctional flexible multistate switch 被引量:1
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作者 Jianghua Liao Wei Gao +1 位作者 Yan Yang Gengjie Yang 《Global Energy Interconnection》 EI CSCD 2024年第2期190-205,共16页
To address the low accuracy and stability when applying classical control theory in distribution networks with distributed generation,a control method involving flexible multistate switches(FMSs)is proposed in this st... To address the low accuracy and stability when applying classical control theory in distribution networks with distributed generation,a control method involving flexible multistate switches(FMSs)is proposed in this study.This approach is based on an improved double-loop recursive fuzzy neural network(DRFNN)sliding mode,which is intended to stably achieve multiterminal power interaction and adaptive arc suppression for single-phase ground faults.First,an improved DRFNN sliding mode control(SMC)method is proposed to overcome the chattering and transient overshoot inherent in the classical SMC and reduce the reliance on a precise mathematical model of the control system.To improve the robustness of the system,an adaptive parameter-adjustment strategy for the DRFNN is designed,where its dynamic mapping capabilities are leveraged to improve the transient compensation control.Additionally,a quasi-continuous second-order sliding mode controller with a calculus-driven sliding mode surface is developed to improve the current monitoring accuracy and enhance the system stability.The stability of the proposed method and the convergence of the network parameters are verified using the Lyapunov theorem.A simulation model of the three-port FMS with its control system is constructed in MATLAB/Simulink.The simulation result confirms the feasibility and effectiveness of the proposed control strategy based on a comparative analysis. 展开更多
关键词 distribution networks Flexible multistate switch Grounding fault arc suppression double-loop recursive fuzzy neural network Quasi-continuous second-order sliding mode
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Tunable Three-Wavelength Fiber Laser and Transient Switching between Three-Wavelength Soliton and Q-Switched Mode-Locked States
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作者 司志增 戴朝卿 刘威 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第2期10-13,共4页
We report a passive mode-locked fiber laser that can realize single-wavelength tuning and multi-wavelength spacing tuning simultaneously.The tuning range is from 1528 nm–1560 nm,and up to three bands of soliton state... We report a passive mode-locked fiber laser that can realize single-wavelength tuning and multi-wavelength spacing tuning simultaneously.The tuning range is from 1528 nm–1560 nm,and up to three bands of soliton states can be output at the same time.These results are confirmed by a nonlinear Schrodinger equation model based on the split-step Fourier method.In addition,we reveal a way to transform the multi-wavelength soliton state into the Q-switched mode-locked state,which is period doubling.These results will promote the development of optical communication,optical sensing and multi-signal pulse emission. 展开更多
关键词 tuning switched switchING
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Interpolated Bumpless Transfer Control for Asynchronously Switched Linear Systems
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作者 Shengao Lu Tong Wu +2 位作者 Lixian Zhang Jianan Yang Ye Liang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第7期1579-1590,共12页
This paper revisits the problem of bumpless transfer control(BTC) for discrete-time nondeterministic switched linear systems. The general case of asynchronous switching is considered for the first time in the field of... This paper revisits the problem of bumpless transfer control(BTC) for discrete-time nondeterministic switched linear systems. The general case of asynchronous switching is considered for the first time in the field of BTC for switched systems. A new approach called interpolated bumpless transfer control(IBTC) is proposed, where the bumpless transfer controllers are formulated with the combination of the two adjacent modedependent controller gains, and are interpolated for finite steps once the switching is detected. In contrast with the existing approaches, IBTC does not necessarily run through the full interval of subsystems, as well as possesses the time-varying controller gains(with more flexibility and less conservatism) achieved from a control synthesis allowing for the stability and other performance of the whole switched system. Sufficient conditions ensuring stability and H_(∞) performance of the underlying system by IBTC are developed, and numerical examples verify the theoretical findings. 展开更多
关键词 Asynchronous switching bumpless transfer H_∞control switched systems
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Switching Frequency Improvement of a High Speed on/off Valve Based on Pre-excitation Control Algorithm
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作者 Qi Zhong Xiaotian Li +4 位作者 Yongxin Mao Enguang Xu Tiwei Jia Yanbiao Li Huayong Yang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第4期94-106,共13页
The high-speed on/off valve(HSV)serves as the fundamental component responsible for generating discrete fluids within digital hydraulic systems.As the switching frequency of the HSV increases,the properties of the gen... The high-speed on/off valve(HSV)serves as the fundamental component responsible for generating discrete fluids within digital hydraulic systems.As the switching frequency of the HSV increases,the properties of the generated discrete fluid approach those of continuous fluids.Therefore,a higher frequency response characteristic of HSV is the key to ensure the control accuracy of digital hydraulic systems.However,the current research mainly focuses on its dynamic performance,but neglect its FRC.This paper presents a theoretical analysis demonstrating that the FRC of the HSV can be enhanced by minimizing its switching time.The maximum switching frequency(MSF)is mainly determined by opening dynamic performance when HSV operates with low switching duty ratio(SDR),whereas the closing dynamic performance limits the MSF when HSV operates with high SDR.Building upon these findings,the pre-excitation control algorithm(PECA)is proposed to reduce the switching time of the HSV,and consequently enhance its FRC.Experimental results demonstrate that PECA shortens the opening delay time of HSV by 1.12 ms,the closing delay time by 2.54 ms,and the closing moving time by 0.47 ms in comparison to the existing advanced control algorithms.As a result,a larger MSF of 417 Hz and a wider controllable SDR range from 20%to 70%were achieved at a switching frequency of 250 Hz.Thus,the proposed PFCA in this paper has been verified as an effective and promising approach for enhancing the control performance of digital hydraulic systems. 展开更多
关键词 High speed on/off valve switching frequency Pre-excitation dynamic performance switching duty ratio
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Iron regulatory protein 1: the deadly switch of ferroptosis
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作者 Daniel A.Bórquez Pamela J.Urrutia 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期477-478,共2页
Ferroptosis,an iron-dependent cell death:Ferroptosis is a type of regulated necrosis,characterized by redox-active iron accumulation and increased free radical production derived by Fenton chemistry,that triggers oxid... Ferroptosis,an iron-dependent cell death:Ferroptosis is a type of regulated necrosis,characterized by redox-active iron accumulation and increased free radical production derived by Fenton chemistry,that triggers oxidation of polyunsaturated fatty acids in phospholipids,loss of cellular membranes integrity,and leakage of intracellular contents. 展开更多
关键词 INTEGRITY switch IRON
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Review of Three-phase Soft Switching Inverters and Challenges for Motor Drives
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作者 Haifeng Lu Qiao Wang +1 位作者 Jianyun Chai Yongdong Li 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第2期177-190,共14页
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 ... 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. 展开更多
关键词 Soft switching inverters Zero-voltage switching Electric vehicles Motor drives
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Recent advancements in continuously scalable conversion-ratio switched-capacitor converter
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作者 Mo Huang Yuanfei Wang +1 位作者 Rui P.Martins Yan Lu 《Journal of Semiconductors》 EI CAS CSCD 2024年第4期8-11,共4页
Switched-capacitor(SC)DC-DC converter[1]is an impor-tant alternative to inductive DC-DC converter,in terms of removing the bulky power inductor.Hence,it is widely used in low-profile,low-power applications,such as the... Switched-capacitor(SC)DC-DC converter[1]is an impor-tant alternative to inductive DC-DC converter,in terms of removing the bulky power inductor.Hence,it is widely used in low-profile,low-power applications,such as the internet of things(IoT)sensor nodes and energy harvesting[2].Mean-while,considering that capacitor has a much higher energy density than inductor,high-power applications. 展开更多
关键词 CONVERTER switchEd removing
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An LED-Side-Pumped Intracavity Frequency-Doubled Nd,Ce:YAG Laser Producing a 2W Q-Switched Red Beam
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作者 沈建平 徐少聪 +6 位作者 芦鹏 江容容 王巍 张四维 邢凤阳 陈阳 陈亮 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第3期44-47,共4页
We report a high-average-power acousto-optic(AO)Q-switched intracavity frequency-doubled red laser based on a high-efficiency light-emitting-diode(LED)pumped two-rod Nd,Ce:YAG laser module.Under quasi-continuous wave ... We report a high-average-power acousto-optic(AO)Q-switched intracavity frequency-doubled red laser based on a high-efficiency light-emitting-diode(LED)pumped two-rod Nd,Ce:YAG laser module.Under quasi-continuous wave operation conditions,a maximum output power of 1319.08 nm wavelength was achieved at 11.26 W at a repetition rate of 100 Hz. 展开更多
关键词 PUMPEd switchEd LASER
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Valley switch effect in anα-T3 lattice-based superconducting interferometer
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作者 Ya-Jun Wei Jun Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期372-377,共6页
Dirac electrons possess a valley degree of freedom,which is currently under investigation as a potential information carrier.We propose an approach to generate and manipulate the valley-switching current(VSC)through A... Dirac electrons possess a valley degree of freedom,which is currently under investigation as a potential information carrier.We propose an approach to generate and manipulate the valley-switching current(VSC)through Andreev reflection using an interferometer-based superconductor hybrid junction.The interferometer comprises a ring-shaped structure formed by topological kink states in the a-T3 lattice via carefully designed electrostatic potentials.Our results demonstrate the feasibility of achieving a fully polarized VSC in this device without contamination from cotunneling electrons sharing the same valley as the incident electron.Furthermore,we show that control over the fully polarized VSC can be achieved by applying a nonlocal gate voltage or modifying the global parameter a.The former alters the dynamic phase of electrons while the latter provides an a-dependent Berry phase,both directly influencing quantum interference and thereby affecting performance in terms of generating and manipulating VSC,crucial for advancements in valleytronics. 展开更多
关键词 valley switch effect valleytronics Andreev reflection a-T3 lattice
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Chalcogenide Ovonic Threshold Switching Selector
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作者 Zihao Zhao Sergiu Clima +4 位作者 Daniele Garbin Robin Degraeve Geoffrey Pourtois Zhitang Song Min Zhu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期1-40,共40页
Today’s explosion of data urgently requires memory technologies capable of storing large volumes of data in shorter time frames,a feat unattain-able with Flash or DRAM.Intel Optane,commonly referred to as three-dimen... Today’s explosion of data urgently requires memory technologies capable of storing large volumes of data in shorter time frames,a feat unattain-able with Flash or DRAM.Intel Optane,commonly referred to as three-dimensional phase change memory,stands out as one of the most promising candidates.The Optane with cross-point architecture is constructed through layering a storage element and a selector known as the ovonic threshold switch(OTS).The OTS device,which employs chalcogenide film,has thereby gathered increased attention in recent years.In this paper,we begin by providing a brief introduction to the discovery process of the OTS phenomenon.Subsequently,we summarize the key elec-trical parameters of OTS devices and delve into recent explorations of OTS materials,which are categorized as Se-based,Te-based,and S-based material systems.Furthermore,we discuss various models for the OTS switching mechanism,including field-induced nucleation model,as well as several carrier injection models.Additionally,we review the progress and innovations in OTS mechanism research.Finally,we highlight the successful application of OTS devices in three-dimensional high-density memory and offer insights into their promising performance and extensive prospects in emerging applications,such as self-selecting memory and neuromorphic computing. 展开更多
关键词 Non-volatile memory Ovonic threshold switch(OTS) CHALCOGENIdE SELECTOR
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Fault Diagnosis Scheme for Railway Switch Machine Using Multi-Sensor Fusion Tensor Machine
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作者 Chen Chen Zhongwei Xu +2 位作者 Meng Mei Kai Huang Siu Ming Lo 《Computers, Materials & Continua》 SCIE EI 2024年第6期4533-4549,共17页
Railway switch machine is essential for maintaining the safety and punctuality of train operations.A data-driven fault diagnosis scheme for railway switch machine using tensor machine and multi-representation monitori... Railway switch machine is essential for maintaining the safety and punctuality of train operations.A data-driven fault diagnosis scheme for railway switch machine using tensor machine and multi-representation monitoring data is developed herein.Unlike existing methods,this approach takes into account the spatial information of the time series monitoring data,aligning with the domain expertise of on-site manual monitoring.Besides,a multi-sensor fusion tensor machine is designed to improve single signal data’s limitations in insufficient information.First,one-dimensional signal data is preprocessed and transformed into two-dimensional images.Afterward,the fusion feature tensor is created by utilizing the images of the three-phase current and employing the CANDE-COMP/PARAFAC(CP)decomposition method.Then,the tensor learning-based model is built using the extracted fusion feature tensor.The developed fault diagnosis scheme is valid with the field three-phase current dataset.The experiment indicates an enhanced performance of the developed fault diagnosis scheme over the current approach,particularly in terms of recall,precision,and F1-score. 展开更多
关键词 Railway switch machine tensor machine fault diagnosis
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Performance of Lateral 4H-SiC Photoconductive Semiconductor Switches by Extrinsic Backside Trigger
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作者 WANG Hao LIU Xuechao +8 位作者 ZHENG Zhong PAN Xiuhong XU Jintao ZHU Xinfeng CHEN Kun DENG Weijie TANG Meibo GUO Hui GAO Pan 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2024年第9期1070-1076,共7页
Photoconductive semiconductor switch(PCSS)can be applied in pulsed high power systems and microwave techniques.However,reducing the damage and increasing the lifetime of silicon carbide(SiC)PCSS are still faced severe... Photoconductive semiconductor switch(PCSS)can be applied in pulsed high power systems and microwave techniques.However,reducing the damage and increasing the lifetime of silicon carbide(SiC)PCSS are still faced severe challenges.In this study,PCSSs with various structures were prepared on 4-inch diameter,500μm thick high-purity semi-insulating 4H-SiC substrates and their on-state resistance and damage mechanisms were investigated.It was found that the PCSS of an Au/TiW/Ni electrode system annealed at 950℃had a minimum on-state resistance of 6.0Ωat 1 kV bias voltage with a 532 nm and 170 mJ pulsed laser by backside illumination single trigger.The backside illumination single trigger could reduce on-state resistance and alleviate the damage of PCSS compared to the frontside trigger when the diameter of the laser spot was larger than the channel length of PCSS.For the 200 s trigger test by a 10 Hz laser,the black branch-like ablation on Au/TiW/Ni PCSS was mainly caused by thermal stress owing to hot carriers.Replacing metal Ni with boron gallium co-doped zinc oxide(BGZO)thin films annealed at 400℃,black branch-like ablation was alleviated while concentric arc damage was obvious at the anode.The major causes of concentric arc are both pulsed laser diffraction and thermal effect. 展开更多
关键词 silicon carbide photoconductive semiconductor switch on-state resistance failure analysis
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An analytical transient coal permeability model:Sorption non-equilibrium index-based swelling switch
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作者 Xingxing Liu Jishan Liu +2 位作者 Liang Chen Jinchang Sheng Huimin Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1175-1191,共17页
Long-term permeability experiments have indicated that sorption-induced swelling can switch from internal to bulk depending on the evolutive sorption status.However,this sorption swelling switch mechanism has not been... Long-term permeability experiments have indicated that sorption-induced swelling can switch from internal to bulk depending on the evolutive sorption status.However,this sorption swelling switch mechanism has not been considered in current analytical permeability models.This study introduces a normalized sorption non-equilibrium index(SNEI)to characterize the sorption status,quantify the dynamical variations of matrix swelling accumulation and internal swelling partition,and formulate the sorption swelling switch model.The incorporation of this index into the extended total effective stress concept leads to an analytical transient coal permeability model.Model results show that the sorption swelling switch itself results in the permeability switch under stress-constrained conditions,while the confined bulk swelling suppresses the permeability recovery to the continuous reduction under displacement-constrained conditions.Model verifications show that current experimental observations correspond to the early stages of the transient process,and they could be extended to the whole process with these models.This study demonstrates the importance of the sorption swelling switch in determining permeability evolution using simple boundary conditions.It provides new insights into experimentally revealing the sorption swelling switch in the future,and underscores the requirement of a rigorous model for complex coupled processes in large-scale coal seams. 展开更多
关键词 Coal permeability Sorption swelling switch Sorption non-equilibrium Boundary conditions
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Resistive switching behavior and mechanism of HfO_(x) films with large on/off ratio by structure design
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作者 黄香林 王英 +2 位作者 黄慧香 段理 郭婷婷 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期660-665,共6页
Different bilayer structures of HfO_(x)/Ti(TiO_(x)) are designed for hafnium-based memory to investigate the switching characteristics. The chemical states in the films and near the interface are characterized by x-ra... Different bilayer structures of HfO_(x)/Ti(TiO_(x)) are designed for hafnium-based memory to investigate the switching characteristics. The chemical states in the films and near the interface are characterized by x-ray photoelectron spectroscopy,and the oxygen vacancies are analyzed. Highly improved on/off ratio(~104) and much uniform switching parameters are observed for bilayer structures compared to single layer HfO_(x) sample, which can be attributed to the modulation of oxygen vacancies at the interface and better control of the growth of filaments. Furthermore, the reliability of the prepared samples is investigated. The carrier conduction behaviors of HfO_(x)-based samples can be attributed to the trapping and de-trapping process of oxygen vacancies and a filamentary model is proposed. In addition, the rupture of filaments during the reset process for the bilayer structures occur at the weak points near the interface by the recovery of oxygen vacancies accompanied by the variation of barrier height. The re-formation of fixed filaments due to the residual filaments as lightning rods results in the better switching performance of the bilayer structure. 展开更多
关键词 HfO_(x)film resistive switching structure design interface modulation
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A framework for dynamic modelling of railway track switches considering the switch blades,actuators and control systems
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作者 Saikat Dutta Tim Harrison +2 位作者 Christopher Ward Roger Dixon Phil Winship 《Railway Engineering Science》 EI 2024年第2期162-176,共15页
The main contribution of this paper is the development and demonstration of a novel methodology that can be followed to develop a simulation twin of a railway track switch system to test the functionality in a digital... The main contribution of this paper is the development and demonstration of a novel methodology that can be followed to develop a simulation twin of a railway track switch system to test the functionality in a digital environment.This is important because,globally,railway track switches are used to allow trains to change routes;they are a key part of all railway networks.However,because track switches are single points of failure and safety-critical,their inability to operate correctly can cause significant delays and concomitant costs.In order to better understand the dynamic behaviour of switches during operation,this paper has developed a full simulation twin of a complete track switch system.The approach fuses finite element for the rail bending and motion,with physics-based models of the electromechanical actuator system and the control system.Hence,it provides researchers and engineers the opportunity to explore and understand the design space around the dynamic operation of new switches and switch machines before they are built.This is useful for looking at the modification or monitoring of existing switches,and it becomes even more important when new switch concepts are being considered and evaluated.The simulation is capable of running in real time or faster meaning designs can be iterated and checked interactively.The paper describes the modelling approach,demonstrates the methodology by developing the system model for a novel“REPOINT”switch system,and evaluates the system level performance against the dynamic performance requirements for the switch.In the context of that case study,it is found that the proposed new actuation system as designed can meet(and exceed)the system performance requirements,and that the fault tolerance built into the actuation ensures continued operation after a single actuator failure. 展开更多
关键词 Railway track switch Mathematical modelling Redundant actuation Finite element analysis
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A Tri-Salt Composite Electrolyte with Temperature Switch Function for Intelligently Temperature-Controlled Lithium Batteries
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作者 Ende Fu Huimin Wang +4 位作者 Yating Zhang Zhenxue Xiao Xiu Zheng Shuai Hao Xueping Gao 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第6期84-93,共10页
The intense research of lithium-ion batteries has been motivated by their successful applications in mobile devices and electronic vehicles.The emerging of intelligent control in kinds of devices brings new requiremen... The intense research of lithium-ion batteries has been motivated by their successful applications in mobile devices and electronic vehicles.The emerging of intelligent control in kinds of devices brings new requirements for battery systems.The high-energy lithium batteries are expected to respond or react under different environmental conditions.In this work,a tri-salt composite electrolyte is designed with a temperature switch function for intelligently temperature-controlled lithium batteries.Specifically,the halide Li_(3)YBr_(6)together with LiTFSI and LiNO_(3)works as active fillers in a low-melting-point polymer matrix(polyethyleneglycol dimethyl ether(PEGDME)and polyethylene oxide(PEO)),which is further filled into the pre-lithiated alumina fiber skeleton.Above 60°C,the composite electrolyte exists in the liquid state and fully contacts with the working electrodes on the liquid–solid interface,effectively minimizing the interfacial resistance and leading to high discharge capacity in the cell.The electrolyte is changed into a solid state below 30°C so that the ionic conductivity is significantly reduced and the interface resistance is increased dramatically on the solid–solid interface.Therefore,by simply adjusting the temperature,the cell can be turned“ON”or“OFF”intentionally.This novel function of the composite electrolyte has enlightening significance in developing intelligently temperature-controlled lithium batteries. 展开更多
关键词 composite electrolyte halide electrolyte low melting point solid-state battery temperature switch function
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Real-world experience and long-term outcomes of a mandatory nonmedical switch of adalimumab originator to biosimilars in inflammatory bowel disease
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作者 Jeremy Liu Chen Kiow Thomas Hoang +6 位作者 Harjot K Bedi Zhina Majdzadeh Ardekani Daniel Rosenfeld Marica Reise-Filteau Brian Bressler Yvette Leung Greg Rosenfeld 《World Journal of Gastroenterology》 SCIE CAS 2024年第46期4904-4913,共10页
BACKGROUND Over the last decade,the treatment options for inflammatory bowel disease(IBD)have significantly progressed with the emergence of new medications designed to target various immune pathways and mitigate infl... BACKGROUND Over the last decade,the treatment options for inflammatory bowel disease(IBD)have significantly progressed with the emergence of new medications designed to target various immune pathways and mitigate inflammation.Adalimumab(ADA)is a tumor necrosis factor alpha antagonist and stands as an effective treatment for IBD.In April 2021,the province of British Columbia implemented a mandatory non-medical switch policy of the ADA originator Humira®to ADA biosimilars.Biosimilars offer a potential cost-effective,safe,and efficacious alternative to the originator,yet there remains limited real-world evidence on long-term outcomes of ADA non-medical switching in IBD.AIM To assess the long-term outcomes of non-medical switching from the ADA originator Humira®to an ADA biosimilar among IBD patients.METHODS A retrospective observational chart review study was conducted on IBD patients eligible for the provincially mandated non-medical switch to an ADA biosimilar.The primary outcome was treatment persistence at 30 months post-switch.Secondary outcomes included the proportion of and reasons for therapy alteration or ADA discontinuation,loss of response(LOR)rates,adverse events(AE),and clinical and biochemical remission status.Patients who remained on the originator throughout the switch period,through compassionate support or private pay,constituted the comparison group.RESULTS Patients in the originator(n=43)and biosimilar switch(n=228)groups displayed similar demographics and baseline disease characteristics.By the study endpoint of 30 months,there was no difference in the rate of treatment persistence in either group(n=36,83.7%originator group vs n=201,88.2%biosimilar group,P=0.451).Treatment persistence demonstrated similar rates of discontinuation between both study groups(log-rank P=0.543).There was a numerical but not statistically significant difference in rates of adverse outcomes between either group(39.5%originator vs 28.9%biosimilars,P=0.206).This included comparable rates of LOR(27.9%vs 17.5%)or AE(11.6%vs 11.4%)between the originator and biosimilar cohorts,respectively.C-reactive protein and fecal calprotectin levels were similar one year pre-and post-switch.CONCLUSION These data support the long-term efficacy and safety of non-medical ADA switching in IBD and will help inform patients and physicians in jurisdictions currently undergoing biosimilar switching. 展开更多
关键词 Inflammatory bowel disease Ulcerative colitis Crohn’s disease BIOLOGICS AdALIMUMAB Biosimilar switch
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