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BIM Base软件在工程算量中精确性与效率提升的研究
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作者 李东霖 张莲珠 李杰 《赤峰学院学报(自然科学版)》 2026年第1期25-31,共7页
本研究针对传统工程算量方法效率低、误差大等问题,探讨基于国产自主BIM Base平台的工程算量软件在提升建筑工程算量精确性与效率中的应用价值。通过理论分析与案例验证,表明该软件采用拓扑关系重建算法和图形相交技术,解决了异形构件... 本研究针对传统工程算量方法效率低、误差大等问题,探讨基于国产自主BIM Base平台的工程算量软件在提升建筑工程算量精确性与效率中的应用价值。通过理论分析与案例验证,表明该软件采用拓扑关系重建算法和图形相交技术,解决了异形构件扣减规则模糊问题,将复杂节点(如梁柱交接)工程量误差压缩至0.5%以内;结合矩阵变换技术优化模型调整流程,利用四叉树图形索引提升空间检索效率,并通过多线程并行计算使算量速度较单线程软件提高5倍以上。案例证明,其碰撞检测功能可规避设计冲突,钢筋避让规则使钢筋算量误差趋近于零,安装算量误差降至0.5%以内,整体效率提升80%以上。研究证实,基于BIM Base平台的自主算量软件能打通“设计—深化—算量—施工”全链条数据传递,推动建筑业数字化转型升级。 展开更多
关键词 BIM base平台 工程算量 拓扑重建 矩阵变换 多线程计算
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Towards mechanism-based tau-targeted therapies
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作者 Lidia Bakota Roland Brandt 《Neural Regeneration Research》 2026年第2期687-688,共2页
Tau plays a crucial role in several neurodegenerative diseases,collectively referred to as tauopathies.Therefore,targeting potential pathological changes in tau could enable useful therapeutic interventions.However,ta... Tau plays a crucial role in several neurodegenerative diseases,collectively referred to as tauopathies.Therefore,targeting potential pathological changes in tau could enable useful therapeutic interventions.However,tau is not an easy target because it dynamically interacts with microtubules and other cellular components,which presents a challenge for tau-targeted drugs.New cellular models could aid the development of mechanism-based tau-targeted therapies. 展开更多
关键词 tau targeted therapies cellular components mechanism based therapies cellular componentswhich cellular models MICROTUBULES TAUOPATHIES neurodegenerative diseasescollectively
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Enhanced Capacity Reversible Data Hiding Based on Pixel Value Ordering in Triple Stego Images
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作者 Kim Sao Nguyen Ngoc Dung Bui 《Computers, Materials & Continua》 2026年第1期1571-1586,共16页
Reversible data hiding(RDH)enables secret data embedding while preserving complete cover image recovery,making it crucial for applications requiring image integrity.The pixel value ordering(PVO)technique used in multi... Reversible data hiding(RDH)enables secret data embedding while preserving complete cover image recovery,making it crucial for applications requiring image integrity.The pixel value ordering(PVO)technique used in multi-stego images provides good image quality but often results in low embedding capability.To address these challenges,this paper proposes a high-capacity RDH scheme based on PVO that generates three stego images from a single cover image.The cover image is partitioned into non-overlapping blocks with pixels sorted in ascending order.Four secret bits are embedded into each block’s maximum pixel value,while three additional bits are embedded into the second-largest value when the pixel difference exceeds a predefined threshold.A similar embedding strategy is also applied to the minimum side of the block,including the second-smallest pixel value.This design enables each block to embed up to 14 bits of secret data.Experimental results demonstrate that the proposed method achieves significantly higher embedding capacity and improved visual quality compared to existing triple-stego RDH approaches,advancing the field of reversible steganography. 展开更多
关键词 RDH reversible data hiding PVO RDH base three stego images
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Correction:Flux‑based assessment of ozone visible foliar injury in Southern Alps
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作者 Elena Marra Alessandra De Marco +8 位作者 Andrea Ebone Anna Maria Ferrara Fabio Giannetti Francesco Tagliaferro Pierre Sicard Andrei Popa Ionel Popa Elena Paoletti Yasutomo Hoshika 《Journal of Forestry Research》 2026年第2期305-305,共1页
Correction to:Journal of Forestry Research(2025)36:124 https://doi.org/10.1007/s11676-025-01918-8 In this article the author’s name Yasutomo Hoshika was incorrectly written as Yasutoma Hoshika.The original article ha... Correction to:Journal of Forestry Research(2025)36:124 https://doi.org/10.1007/s11676-025-01918-8 In this article the author’s name Yasutomo Hoshika was incorrectly written as Yasutoma Hoshika.The original article has been corrected. 展开更多
关键词 visible foliar injury southern Alps flux based assessment yasutomo hoshika journal forestry research yasutoma hoshikathe OZONE
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Height-based biomass models differ for naturally regenerated and planted young trees
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作者 Peter Marcis Jozef Pajtík +1 位作者 Bohdan Konôpka Martin Lukac 《Forest Ecosystems》 2026年第1期178-187,共10页
This study investigated biomass allocation in young stands of European beech(Fagus sylvatica L.)and Norway spruce(Picea abies(L.)Karst.)across 31 forest sites in the Western Carpathians,Slovakia.A total of 541 trees a... This study investigated biomass allocation in young stands of European beech(Fagus sylvatica L.)and Norway spruce(Picea abies(L.)Karst.)across 31 forest sites in the Western Carpathians,Slovakia.A total of 541 trees aged 2–10 years,originating from natural regeneration and planting,were destructively sampled to quantify biomass in four components:foliage,branches,stems,and roots.Generalized non-linear least squares(GNLS)models with a weighing variance function outperformed log-transformed seemingly unrelated regression(SUR)models in terms of accuracy and robustness,especially for foliage and branch biomass.When using height as the predictor,SUR models tended to underestimate biomass in planted beech,leading to notable underprediction of aboveground and total biomass.Biomass allocation patterns varied significantly by species and regeneration origin.Using a non-linear system of equations and component ratio modelling,we found out that planted spruce displayed low variability and a consistent dominance of needle biomass,while naturally regenerated beech showed greater variability and a higher proportion of stem biomass,reflecting stronger competition-driven vertical growth.Interspecific differences in total biomass were more pronounced when using tree height,with spruce generally exhibiting greater biomass than beech at equivalent heights.Overall,stem base diameter marginally outperformed tree height as a predictor of biomass.However,tree height-based models showed strong performance and are particularly suitable for integration with remote sensing applications.These findings can directly support forest managers and modellers in comparing regeneration methods and biomass estimation approaches for early-stage stand development,carbon accounting,and remote sensing calibration. 展开更多
关键词 European beech Norway spruce Allometric relations Tree height Diameter at base Whole-tree biomass Tree components
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Secured-FL:Blockchain-Based Defense against Adversarial Attacks on Federated Learning Models
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作者 Bello Musa Yakubu Nor Shahida Mohd Jamail +1 位作者 Rabia Latif Seemab Latif 《Computers, Materials & Continua》 2026年第3期734-757,共24页
Federated Learning(FL)enables joint training over distributed devices without data exchange but is highly vulnerable to attacks by adversaries in the form of model poisoning and malicious update injection.This work pr... Federated Learning(FL)enables joint training over distributed devices without data exchange but is highly vulnerable to attacks by adversaries in the form of model poisoning and malicious update injection.This work proposes Secured-FL,a blockchain-based defensive framework that combines smart contract-based authentication,clustering-driven outlier elimination,and dynamic threshold adjustment to defend against adversarial attacks.The framework was implemented on a private Ethereum network with a Proof-of-Authority consensus algorithm to ensure tamper-resistant and auditable model updates.Large-scale simulation on the Cyber Data dataset,under up to 50%malicious client settings,demonstrates Secured-FL achieves 6%-12%higher accuracy,9%-15%lower latency,and approximately 14%less computational expense compared to the PPSS benchmark framework.Additional tests,including confusion matrices,ROC and Precision-Recall curves,and ablation tests,confirm the interpretability and robustness of the defense.Tests for scalability also show consistent performance up to 500 clients,affirming appropriateness to reasonably large deployments.These results make Secured-FL a feasible,adversarially resilient FL paradigm with promising potential for application in smart cities,medicine,and other mission-critical IoT deployments. 展开更多
关键词 Federated learning(FL) blockchain FL based privacy model defense FL model security ethereum smart contract
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Improvement of Traveling Wave-based Fault Location Method for Overhead Distribution Lines
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作者 Xinyi Zhang Bingyin Xu +1 位作者 Zhaoru Han Fang Shi 《Protection and Control of Modern Power Systems》 2026年第1期157-172,共16页
Traveling wave(TW)fault location technology has been widely used in transmission systems due to its high accuracy and simplicity.Recently,there has been growing interest in applying this technology to medium voltage(M... Traveling wave(TW)fault location technology has been widely used in transmission systems due to its high accuracy and simplicity.Recently,there has been growing interest in applying this technology to medium voltage(MV)distribution lines.However,current practices in its deployment,signal measurement,and threshold setting are usually from the application experiences in transmission lines,despite significant differences in fault-induced wave characteristics between transmission and distribution systems.To address these issues,this paper investigates the feasibility and applicability of TW fault technology in MV overhead distribution lines through characteristic analysis of fault-induced TWs.The propagation characteristics of aerial mode and zero mode TWs on overhead distribution lines are studied.Furthermore,it evaluates the influence of critical distri-bution network components including distribution transformers,multi-branch configurations,and busbar structures on wave propagation characteristics.Deployment strategies for traveling wave fault location(TWFL)devices is proposed to address the unique challenges of distribution networks,while the fault location method is also improved.Field test results demonstrate the effectiveness of the proposed methodology,showing improved fault detection accuracy and system reliability in distri-bution network applications.This research provides practical implementation suggestions for TWFL technology in distribution networks. 展开更多
关键词 Branch lines distribution network overhead lines propagation characteristics traveling wave based fault location
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Zirconium-and hafnium-based chalcogenide perovskites:From materials to devices and applications
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作者 Hicham Zalrhi Salma Daim +4 位作者 Mohammed Makha Nelson Yaw Dzade Abdelkader Outzourhit Mohammed Abd-lefdil Lahoucine Atourki 《Journal of Energy Chemistry》 2026年第3期448-472,共25页
Chalcogenide perovskites(CPs)based on zirconium(Zr)and hafnium(Hf)are becoming increasingly attractive as a new class of materials for next-generation solar cells.CPs with the ABX_(3) structure stand out due to their ... Chalcogenide perovskites(CPs)based on zirconium(Zr)and hafnium(Hf)are becoming increasingly attractive as a new class of materials for next-generation solar cells.CPs with the ABX_(3) structure stand out due to their attractive optical and electrical properties,such as efficient light absorption,direct bandgaps in the range of 1.1–2.1 eV,and remarkable defect tolerance,making them a compelling alternative to hybrid and double perovskites for solar energy conversion.Although theoretical studies have progressed rapidly,experimental verification still faces challenges such as the high synthesis temperatures required(>900℃),particularly in producing high-quality,phase-pure thin films and scalable solution-based processes.In this review,we aim to provide a comprehensive overview of the progress and remaining obstacles in advancing CP-based materials and devices.First,we describe the structure and composition as well as the different CPs in which the B site is occupied by Zr and Hf.Second,we summarize the methods used and the challenges that researchers face in producing an effective device.We highlight the main features that make CPs a preferred option for photovoltaic and other applications.Third,we look at the progress made in simulating solar cells that can achieve a power conversion efficiency(PCE)of over 30%using SCAPS-1D software.In the end,challenges and future research directions toward the development of CP materials and devices are provided.Overall,this review will serve as a valuable resource for researchers in selecting suitable strategies to achieve high-performance optoelectronic devices. 展开更多
关键词 Chalcogenide perovskites Lead-free perovskites Solar energy conversion Thin-film fabrication Photovoltaic materials Perovskite based solar cells
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Erratum:Marine Shell-Inspired Laser Surface Texturing:Characterizing the Surface Properties of Co-Based Alloy
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作者 Sefika Kasman Sertan Ozan 《Journal of Bionic Engineering》 2026年第1期551-551,共1页
The original online version of this article was revised:Several errors occurred in the published version of the article.These have now been corrected as follows:Page 2,section"2.2 Laser Texturing Procedure of Sur... The original online version of this article was revised:Several errors occurred in the published version of the article.These have now been corrected as follows:Page 2,section"2.2 Laser Texturing Procedure of Surfaces",line 2:The device name was corrected from"YDFLP-E-50-M8"to"YDFLP-50-M8."Page 3,Section 2.4:The phrase"95%confidence interval"has been corrected to"95%confidence level."Page 3,Figure 1 caption:The phrase"fandg"has been corrected to"f and g."The order"C4 and C12"has been reversed to"C12 and C4,"in accordance with the display order in the figure.Page 4,Figure reference:The phrase"Figs.4c and d"has been corrected to"Figs.5b and c."Page 5,paragraph starting with"The ANOVA results are presented...":The phrase"95%confidence interval"has been corrected to"95%confidence level." 展开更多
关键词 laser surface texturing surface properties marine shell inspired co based alloy laser texturing procedure confidence level ANOVA results
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One-step generation of sh2isu1 sweet maize via CRISPR/Cas9 cytosine base editor(CBE)
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作者 Lu Zhang Yao Wang +7 位作者 Mengyuan Liu Ziheng Song Xiaoxu Li Yue Fu Panchao Wang Ya Liu Ronghuan Wang Jiuran Zhao 《Journal of Integrative Agriculture》 2026年第3期1297-1300,共4页
Maize(Zea mays L.)is recognized as one of the most significant cereal crops worldwide,serving as a primary source of human food,animal feed,and industrial raw materials.With increasing diversification of market demand... Maize(Zea mays L.)is recognized as one of the most significant cereal crops worldwide,serving as a primary source of human food,animal feed,and industrial raw materials.With increasing diversification of market demands for specialty maize varieties,distinctive fresh produce cultivars characterized by unique textures have gained considerable popularity among consumers(Boyer and Shannon 1984).Notably,sweet maize is often referred to as the‘King of fruits and vegetables'due to its richness in polysaccharides,dietary fiber,trace elements,vitamins,linoleic acid,and other essential nutrients(Revilla et al.2021). 展开更多
关键词 fresh produce cultivars specialty maize CRISPR Cas cytosine base editor sweet maize zea mays fresh produce sh isu
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LLMKB:Large Language Models with Knowledge Base Augmentation for Conversational Recommendation
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作者 FANG Xiu QIU Sijia +1 位作者 SUN Guohao LU Jinhu 《Journal of Donghua University(English Edition)》 2026年第1期91-103,共13页
Conversational recommender systems(CRSs)focus on refining preferences and providing personalized recommendations through natural language interactions and dialogue history.Large language models(LLMs)have shown outstan... Conversational recommender systems(CRSs)focus on refining preferences and providing personalized recommendations through natural language interactions and dialogue history.Large language models(LLMs)have shown outstanding performance across various domains,thereby prompting researchers to investigate their applicability in recommendation systems.However,due to the lack of task-specific knowledge and an inefficient feature extraction process,LLMs still have suboptimal performance in recommendation tasks.Therefore,external knowledge sources,such as knowledge graphs(KGs)and knowledge bases(KBs),are often introduced to address the issue of data sparsity.Compared to KGs,KBs possess higher retrieval efficiency,making them more suitable for scenarios where LLMs serve as recommenders.To this end,we introduce a novel framework integrating LLMs with KBs for enhanced retrieval generation,namely LLMKB.LLMKB initially leverages structured knowledge to create mapping dictionaries,extracting entity-relation information from heterogeneous knowledge to construct KBs.Then,LLMKB achieves the embedding calibration between user information representations and documents in KBs through retrieval model fine-tuning.Finally,LLMKB employs retrievalaugmented generation to produce recommendations based on fused text inputs,followed by post-processing.Experiment results on two public CRS datasets demonstrate the effectiveness of our framework.Our code is publicly available at the link:https://anonymous.4open.science/r/LLMKB-6FD0. 展开更多
关键词 recommender system large language model(LLM) knowledge base(KB)
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Home-Based Care Service
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作者 XU JUNXING 《China Today》 2026年第3期70-72,共3页
Hebei Province has incorporated targeted assistance services for people with disabilities into livelihood projects,upgrading the quality and efficiency of support services for disadvantaged groups.THE living and nursi... Hebei Province has incorporated targeted assistance services for people with disabilities into livelihood projects,upgrading the quality and efficiency of support services for disadvantaged groups.THE living and nursing allowances provided by the Chinese government for people with disabilities who are unable to work are not only important components of China’s social security system which provide for the needs of its disabled,but also show China’s ability to guarantee the basic living standard and social fairness and justice for this group of people. 展开更多
关键词 livelihood projects home based care targeted assistance livelihood projectsupgrading people disabilities living nursing allowances targeted assistance services social security system
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Single-Dimensional Encryption Against Stealthy Attacks on Stochastic Event-Based Estimation
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作者 Jun Shang Di Zhao +1 位作者 Hanwen Zhang Dawei Shi 《IEEE/CAA Journal of Automatica Sinica》 2026年第1期233-235,共3页
Dear Editor,This letter studies the problem of stealthy attacks targeting stochastic event-based estimation,alongside proposing measures for their mitigation.A general attack framework is introduced,and the correspond... Dear Editor,This letter studies the problem of stealthy attacks targeting stochastic event-based estimation,alongside proposing measures for their mitigation.A general attack framework is introduced,and the corresponding stealthiness condition is analyzed.To enhance system security,we advocate for a single-dimensional encryption method,showing that securing a singular data element is sufficient to shield the system from the perils of stealthy attacks. 展开更多
关键词 enhance system securitywe securing singular data element single dimensional encryption stochastic event based estimation stealthiness condition security mitigation attack framework stealthy attacks
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FedPA:Federated Learning with Performance-Based Averaging for Efficient Medical Image Classification
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作者 Atif Mahmood Yasin Saleem +2 位作者 Usman Tariq Yousef Ibrahim Daradkeh Adnan N.Qureshi 《Computer Modeling in Engineering & Sciences》 2026年第3期1077-1101,共25页
Federated learning is a decentralized model training paradigm with significant potential.However,the quality of Federated Network’s client updates can vary due to non-IID data distributions,leading to suboptimal glob... Federated learning is a decentralized model training paradigm with significant potential.However,the quality of Federated Network’s client updates can vary due to non-IID data distributions,leading to suboptimal global models.To address this issue,we propose a novel client selection strategy called FedPA(Performance-Based Federated Averaging).This proposed model selectively aggregates client updates based on a predefined performance threshold.Only clients whose local models achieve an F1 score of 70%or higher after training are included in the aggregation process.Clients below this threshold receive the updated global model but do not contribute their parameters.In this way,the low-performance clients are still in the process of learning and,after some rounds,will be able to contribute.If no client meets the performance threshold in a given round,the system falls back to standard FedAvg aggregation.This ensures the global model continues to improve even when most clients perform poorly.We evaluate FedPA on a subset of the MURA dataset for abnormality detection in radiographs of four bone types.Compared to baseline federated learning algorithms such as Federated Averaging(FedAvg),Federated Proximal(FedProx),Federated Stochastic Gradient Descent(FedSGD),and Federated Batch Normalization(FedBN),FedPA consistently ranks first or second across key performance metrics,particularly in accuracy,F1 score,and recall.Moreover,FedPA demonstrates notable efficiency,achieving the lowest average round time(≈2270 s)and minimal memory usage(≈645.58 MB),all without relying on GPU resources.These results highlight FedPA’s effectiveness in improving global model quality while reducing computational overhead,positioning it as a promising approach for real-world federated learning applications in resource-constrained environments. 展开更多
关键词 Performance based federated learning(FedPA) distributed machine learning industrial growth public health
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Intelligent Reconfigurable Skyrmion-Based Multi-Port Logic Device for In-Memory Computing
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作者 Fuhao Zou Ziyuan Liu +3 位作者 Zijing Zhao Muhammad Humayun Chundong Wang Xiaolei Wang 《Chinese Physics Letters》 2026年第3期331-345,共15页
New electronic devices based on the physical properties of electrically driven skyrmions are promising for logic computing and nonvolatile memory applications.However,achieving efficient and practical compute-storage ... New electronic devices based on the physical properties of electrically driven skyrmions are promising for logic computing and nonvolatile memory applications.However,achieving efficient and practical compute-storage integration remains challenging owing to the structural complexity,limited functionality,and low flexibility observed in most skyrmion-based devices.In this study,we designed a novel device architecture that integrates seven basic logic gates into a unified physical structure.Their operation can be enabled by physical mechanisms,such as spin-orbit torque,spin-transfer torque,skyrmion-edge repulsions,and skyrmion-skyrmion interactions.Furthermore,by incorporating voltage-controlled magnetic anisotropy,the device achieved multi-input capability and reconfigurability functionality.Ultralow power consumption(<1 fJ/bit per logic function)and extremely high logic density were achieved.Significantly,the compatibility of this nanotrack design with existing skyrmion racetrack memory paves the way for advanced in-memory computing in spintronic architectures. 展开更多
关键词 voltage controlled magnetic anisotropy intelligent reconfigurable skyrmion based multi port logic device memory computing logic computing device architecture spin transfer torque spin orbit torque integrates seven basic logic gates
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含Tröger’s base结构聚(苯并噁唑-酰亚胺)热重排分离膜的制备与其气体分离特性研究
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作者 宋映晓 唐傲 +3 位作者 张家霖 董杰 赵昕 张清华 《高分子学报》 北大核心 2025年第8期1358-1368,共11页
设计合成了一种新型含Tröger’s base(TB)结构的二胺单体—2,8-二氨基-4,10-二甲基-6,12-氢-5,11-亚甲二苯并[1,5]二氮辛(TBDA),并将其与2,2′-双(3,4-二羧酸)六氟丙烷二酐(6FDA)和2,2-双(3-氨基-4-羟基苯基)六氟丙烷(APAF)共聚反... 设计合成了一种新型含Tröger’s base(TB)结构的二胺单体—2,8-二氨基-4,10-二甲基-6,12-氢-5,11-亚甲二苯并[1,5]二氮辛(TBDA),并将其与2,2′-双(3,4-二羧酸)六氟丙烷二酐(6FDA)和2,2-双(3-氨基-4-羟基苯基)六氟丙烷(APAF)共聚反应,合成了一系列含邻羟基酰亚胺单元的聚酰亚胺(HPI).在高温下对HPI膜进行热重排处理,获得了兼具TB自聚微孔结构和热重排结构的聚(苯并噁唑-酰亚胺)气体分离膜.研究结果显示,TB自具微孔结构和热重排结构的协同作用抑制了分子链的规整堆砌,使分离膜自由体积增加,从而赋予其优异的气体分离特性.经430℃热重排反应的6FTB1-TR430膜表现出最优异的综合气体分离性能,对CO_(2)、CH_(4)、O_(2)和N_(2)的渗透系数分别为267.6、7.0、57.2和12.5 Barrer(1 Barrer=7.5×10^(−14) cm^(3)(STP)/(cm^(2)·s·Pa),STP表示标准状态,即0℃,1.01×10^(5)Pa),同时,选择性分别达到α(CO_(2)/CH_(4))=38.2及α(O_(2)/N_(2))=4.6.此外,该类分离膜的热分解温度为530~560℃,玻璃化转变温度(Tg)超过400℃,显示出优异的热稳定性.该研究为设计和开发聚酰亚胺类高效气体分离膜提供了新的思路. 展开更多
关键词 Tröger’s base结构 热重排反应 协同作用 气体分离膜
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结合Diffusion-Based WGANGP的变压器油纸绝缘老化状态拉曼光谱检测方法 被引量:3
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作者 陈新岗 敖怡 +5 位作者 张知先 马志鹏 张文轩 万福 况露 罗博文 《光谱学与光谱分析》 北大核心 2025年第8期2164-2173,共10页
提出了一种结合拉曼光谱与扩散模型改进的Wasserstein生成对抗网络(WGANGP)方法,用于提高变压器油纸绝缘老化状态的检测精度。凭借拉曼光谱技术无接触、不损耗的优势,可通过其分析油浸式电力变压器内部油纸绝缘材料的老化产物来评估变... 提出了一种结合拉曼光谱与扩散模型改进的Wasserstein生成对抗网络(WGANGP)方法,用于提高变压器油纸绝缘老化状态的检测精度。凭借拉曼光谱技术无接触、不损耗的优势,可通过其分析油浸式电力变压器内部油纸绝缘材料的老化产物来评估变压器的老化程度。结合深度学习分类模型简化了拉曼光谱数据预处理过程,但此类模型对训练数据的数量和质量有较高要求,由于热加速老化实验周期长,导致可用于训练的有效拉曼光谱数据集相对稀少,限制了分类模型性能。为了解决这一难题,本研究引入了一种新的数据增强方法,即基于扩散模型的WGANGP(Diffusion-Based WGANGP),该方法通过将去噪扩散概率模型的前向加噪过程与WGANGP相结合,向WGANGP中引入实例化的噪声,去除了传统WGANGP的生成器结构中的复杂向上采样过程,简化了数据增强模型结构,有利于模型参数优化。相比于传统GAN及其变体,这种方法不仅保持了变压器油纸绝缘老化样本拉曼光谱数据集的原始特征峰特征与老化程度相关的基线漂移趋势,且与原始数据集特征保持近似的空间分布,生成的数据集信噪比(SNR)为24.84 dB,相比于原始数据集提高了32.11%;同时,也提升了生成样本的多样性,提高了基于深度学习的老化诊断模型的泛化能力、定量分析能力和鲁棒性。实验结果表明,采用Diffusion-Based WGANGP数据增强模型所生成的拉曼光谱数据集,在多个分类模型上的表现均优于其他数据增强方法,特别是在与ResNet-SVM分类模型结合时,在Accuracy(准确性,0.9974)、F1 score(F1分数,0.9969)、Recall(召回率,0.9960)和Precision(精确度,0.9980)四个评价指标上均表现出优势,这表明改进后的数据增强模型能够有效解决变压器老化绝缘油样本稀缺的问题,同时提高了分类模型对变压器老化状态的定量诊断能力。 展开更多
关键词 变压器 油纸绝缘 拉曼光谱 Diffusion-based WGANGP 故障诊断
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孟德尔随机化MR-Base数据库的应用 被引量:1
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作者 蒿花 陈新欢 +3 位作者 姜红 耿辉 马茂 米白冰 《中国循证心血管医学杂志》 2025年第3期270-273,共4页
越来越多的流行病学证据表明,生活方式、饮食习惯等环境因素与多种健康状况之间存在复杂的因果关系。然而,传统的观察性研究易受到混杂因素的影响,无法准确揭示疾病与环境间的因果关系。孟德尔随机化研究(Mendelian Randomization,MR)... 越来越多的流行病学证据表明,生活方式、饮食习惯等环境因素与多种健康状况之间存在复杂的因果关系。然而,传统的观察性研究易受到混杂因素的影响,无法准确揭示疾病与环境间的因果关系。孟德尔随机化研究(Mendelian Randomization,MR)通过遗传变异的随机分配可有效减少混杂因素偏倚,从而更可靠地估计因果效应。MR-Base数据库作为全球最大的孟德尔随机化研究平台,汇集了来自世界各地的遗传数据,为研究者提供了探索遗传变异与健康结局之间因果关系的宝贵资源。本文探讨孟德尔随机化在MR-Base数据库中的应用,旨在介绍该方法的基本原理、数据库的结构与功能,以及如何利用这些数据来探索环境因素与包括心血管疾病、代谢性疾病和精神健康研究等在内的健康结局潜在关联。同时,本文展望了孟德尔随机化方法的未来发展方向,强调了其在精准医疗和公共卫生政策中的潜在作用。 展开更多
关键词 MR-base数据库 孟德尔随机化 遗传变异 工具变量
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RUNX2 is essential for maintaining synchondrosis chondrocytes and cranial base growth 被引量:1
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作者 Shawn A.Hallett Ashley Dixon +9 位作者 Isabella Marrale Lena Batoon JoséBrenes Annabelle Zhou Ariel Arbiv Vesa Kaartinen Benjamin Allen Wanida Ono Renny T.Franceschi Noriaki Ono 《Bone Research》 2025年第4期939-956,共18页
The cranial base synchondroses,comprised of opposite-facing bidirectional chondrocyte layers,drive anteroposterior cranial base growth.In humans,RUNX2 haploinsufficiency causes cleidocranial dysplasia associated with ... The cranial base synchondroses,comprised of opposite-facing bidirectional chondrocyte layers,drive anteroposterior cranial base growth.In humans,RUNX2 haploinsufficiency causes cleidocranial dysplasia associated with deficient midfacial growth.However,how RUNX2 regulates chondrocytes in the cranial base synchondroses remains unknown.To address this,we inactivated Runx2 in postnatal synchondrosis chondrocytes using a tamoxifen-inducible Fgfr3-creER(Fgfr3-Runx2cKO)mouse model.Fgfr3-Runx2cKO mice displayed skeletal dwarfism and reduced anteroposterior cranial base growth associated with premature synchondrosis ossification due to impaired chondrocyte proliferation,accelerated hypertrophy,apoptosis,and osteoclast-mediated cartilage resorption.Lineage tracing reveals that Runx2-deficient Fgfr3+cells failed to differentiate into osteoblasts.Notably,Runx2-deficient chondrocytes showed an elevated level of FGFR3 and its downstream signaling components,pERK1/2 and SOX9,suggesting that RUNX2 downregulates FGFR3 in the synchondrosis.This study unveils a new role of Runx2 in cranial base chondrocytes,identifying a possible RUNX2-FGFR3-MAPK-SOX9 signaling axis that may control cranial base growth. 展开更多
关键词 cranial base synchondroses chondrocyte proliferation HYPERTROPHY cleidocranial dysplasia cranial base synchondrosescomprised apoptosis inactivated runx RUNX
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