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CRB:A new rumor blocking algorithm in online social networks based on competitive spreading model and influence maximization 被引量:1
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作者 董晨 徐桂琼 孟蕾 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期588-604,共17页
The virtuality and openness of online social platforms make networks a hotbed for the rapid propagation of various rumors.In order to block the outbreak of rumor,one of the most effective containment measures is sprea... The virtuality and openness of online social platforms make networks a hotbed for the rapid propagation of various rumors.In order to block the outbreak of rumor,one of the most effective containment measures is spreading positive information to counterbalance the diffusion of rumor.The spreading mechanism of rumors and effective suppression strategies are significant and challenging research issues.Firstly,in order to simulate the dissemination of multiple types of information,we propose a competitive linear threshold model with state transition(CLTST)to describe the spreading process of rumor and anti-rumor in the same network.Subsequently,we put forward a community-based rumor blocking(CRB)algorithm based on influence maximization theory in social networks.Its crucial step is to identify a set of influential seeds that propagate anti-rumor information to other nodes,which includes community detection,selection of candidate anti-rumor seeds and generation of anti-rumor seed set.Under the CLTST model,the CRB algorithm has been compared with six state-of-the-art algorithms on nine online social networks to verify the performance.Experimental results show that the proposed model can better reflect the process of rumor propagation,and review the propagation mechanism of rumor and anti-rumor in online social networks.Moreover,the proposed CRB algorithm has better performance in weakening the rumor dissemination ability,which can select anti-rumor seeds in networks more accurately and achieve better performance in influence spread,sensitivity analysis,seeds distribution and running time. 展开更多
关键词 online social networks rumor blocking competitive linear threshold model influence maximization
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Strange Nonchaotic Attractors in a Quasiperiodically Excited Slender Rigid Rocking Block with Two Frequencies 被引量:1
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作者 Jinkai Jiang Zhengdong Du 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2024年第5期750-761,共12页
In this paper,we investigate the existence of strange nonchaotic attractors(SNAs)in a slender rigid rocking block under quasi-periodic forcing with two frequencies.We find that an SNA can exist between a quasi-periodi... In this paper,we investigate the existence of strange nonchaotic attractors(SNAs)in a slender rigid rocking block under quasi-periodic forcing with two frequencies.We find that an SNA can exist between a quasi-periodic attractor and a chaotic attractor,or between two chaotic attractors.In particular,we demonstrate that a torus doubling bifurcation of a quasi-periodic attractor can result in SNAs via the fractal route before transforming into chaotic attractors.This phenomenon is rarely reported in quasiperiodically forced discontinuous differential equations and vibro-impact systems.The properties of SNAs are verified by the Lyapunov exponent,rational approximation,phase sensitivity,power spectrum,and separation of nearby trajectories. 展开更多
关键词 Strange nonchaotic attractor Slender rigid rocking block Quasi-periodic excitation Chaos Lyapunov exponent
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改良Twin-block矫治器联合微种植体支抗治疗安氏Ⅱ类1分类错[牙合]畸形效果评价
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作者 卢春燕 崔雪蕾 曹培培 《上海口腔医学》 2025年第2期152-156,共5页
目的:探讨改良Twin-block矫治器联合微种植体支抗治疗安氏Ⅱ类1分类错[牙合]畸形的效果。方法:回顾性分析2018年1月—2022年1月如皋市中医院收治的96例安氏Ⅱ类1分类错[牙合]畸形患者资料,根据治疗方法分为试验组(52例)和对照组(44例),... 目的:探讨改良Twin-block矫治器联合微种植体支抗治疗安氏Ⅱ类1分类错[牙合]畸形的效果。方法:回顾性分析2018年1月—2022年1月如皋市中医院收治的96例安氏Ⅱ类1分类错[牙合]畸形患者资料,根据治疗方法分为试验组(52例)和对照组(44例),对照组采用改良Twin-block矫治器,试验组采用改良Twin-block矫治器联合微种植体支抗。比较2组矫治时间、咬合打开时间、排列整齐时间、上下牙槽座角(ANB)、下牙槽座角(SNB)、上牙槽座角(SNA)、上中切牙长轴与NA连线的夹角(U1-NA)、下中切牙长轴与NA连线的夹角(U1-NB)、上颌中切牙长轴与前颅底平面夹角(U1-SN)、下颌中切牙长轴与下颌平面的后上交角(L1-MP)、上颌唇突度(ULP)、下颌唇突度(LLP)、上下唇突点与颏前点切线和眼耳平面夹角(Z角)、菌斑指数(PLI)、牙龈指数(GI)和龈沟出血指数(SBI)。记录并发症及患者满意度。采用SPSS 24.0软件包对数据进行统计学分析。结果:试验组患者矫治时间、咬合打开时间及排列整齐时间显著少于对照组(P<0.05)。治疗后,2组ANB、U1-NA和U1-SN小于治疗前,试验组显著小于对照组(P<0.05);U1-NB、L1-MP大于治疗前,试验组显著大于对照组(P<0.05);SNB、SNA相比无显著差异(P>0.05)。治疗后,2组ULP、LLP低于治疗前,试验组显著低于对照组(P<0.05);Z角升高,试验组显著高于对照组(P<0.05);PLI低于治疗前,试验组显著低于对照组(P<0.05);GI、SBI相比无显著差异(P>0.05)。2组患者满意度相比无显著差异(P>0.05)。结论:改良Twin-block矫治器联合微种植体支抗治疗安氏Ⅱ类1分类错[牙合]畸形,有助于缩短矫治时间,改善颌骨及面部软组织轮廓,促进牙美学效果的恢复。 展开更多
关键词 错[牙合]畸形 安氏Ⅱ类1分类错[牙合] 改良Twin-block矫治器 微种植体支抗
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Ordered Bicontinuous Network Structures Regulated by Orientational Interactions in a Rod-Coil Block Copolymer
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作者 Xiao-Lin Lyu Shi-Chu Yang +6 位作者 An-Qi Xiao Ping-Ping Hou Wei Zhang Hong-Bing Pan Zhi-Hao Shen Xing-He Fan Qi-Feng Zhou 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第5期636-642,I0008,共8页
The rich phase behavior of block copolymers(BCPs)has drawn great attention in recent years.However,the double diamond(DD)phase is rarely obtained because of the competition between the minimization of interfacial ener... The rich phase behavior of block copolymers(BCPs)has drawn great attention in recent years.However,the double diamond(DD)phase is rarely obtained because of the competition between the minimization of interfacial energy and packing frustration.Here,a rod-coil BCP containing mesogen-jacketed liquid crystalline polymer is designed to acquire ordered bicontinuous network nanostructures.The reduction of internal energy originating from the orientational interaction among the rod blocks can compensate for the free energy penalty of packing frustration to stabilize the DD structure.The resulting BCP can also experience lamellae-to-DD and double gyroid-to-lamellae transitions by changing the annealing temperature.These results make the rod-coil BCP an excellent candidate for the self-assembly of ordered network structures,demonstrating great potential in nanopatterning and metamaterials. 展开更多
关键词 block copolymer ROD-COIL Ordered bicontinuous phase Double diamond Double gyroid
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Pass矫治器与Twin-block功能矫治器联合自锁托槽在安氏Ⅱ类1分类错[牙合]畸形中的矫正效果比较
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作者 黄飞 陈倩 张胜男 《中国现代医学杂志》 2025年第6期6-11,共6页
目的对比Pass矫治器与Twin-block功能矫治器联合自锁托槽在安氏Ⅱ类1分类错[牙合]畸形中的矫正效果。方法选取2020年2月—2022年5月在彭州市中医医院就诊的安氏Ⅱ类1分类错[牙合]畸形患者72例,采用随机数字表法将其分成研究组和对照组,... 目的对比Pass矫治器与Twin-block功能矫治器联合自锁托槽在安氏Ⅱ类1分类错[牙合]畸形中的矫正效果。方法选取2020年2月—2022年5月在彭州市中医医院就诊的安氏Ⅱ类1分类错[牙合]畸形患者72例,采用随机数字表法将其分成研究组和对照组,每组36例。对照组接受Twin-block功能矫治器联合自锁托槽治疗,研究组接受Pass矫治器治疗。对比两组临床疗效、颌牙排齐时间、硬组织头影测量指标[上中切牙轴与蝶鞍中心-鼻根点平面夹角(U1-SN)、下中切牙轴与鼻根点-上齿槽座点连接角(U1-NA)、上齿槽座点、鼻根点及下次槽座点连接角(ANB)、蝶鞍中心、鼻根点及上齿槽座点连接角(SNA)]、软组织头影测量目标[上唇到审美平面距离(TUL-FP)、下唇H线距、下唇到审美平面距离(TLL-FP)、鼻唇角]、矫治效果及患者满意度。结果研究组总有效率高于对照组(P<0.05)。研究组上颌牙排齐时间和下颌牙排齐时间均短于对照组(P<0.05)。两组治疗前后U1-SN、ANB、SNA、SNB的差值比较,差异无统计学意义(P>0.05)。研究组治疗前后U1-NA的差值高于对照组(P<0.05)。研究组治疗前后下唇H线距、TUL-FP、鼻唇角、TLL-FP的差值高于对照组(P<0.05)。研究组治疗前后同行评估等级指数(PAR)评分的差值高于对照组(P<0.05)。研究组满意度高于对照组(P<0.05)。结论相比于Twin-block功能矫治器联合自锁托槽,Pass矫治器治疗安氏Ⅱ类1分类错[牙合]畸形患者效果确切,可提高矫治效果,改善面部侧貌美学,缩短颌牙排齐时间,且患者满意度较高。 展开更多
关键词 安氏Ⅱ类1分类错[牙合]畸形 Pass矫治器 TWIN-block功能矫治器 自锁托槽 矫正效果
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安氏Ⅱ类错[牙合]畸形佩戴Twin-block矫治器时上颌骨的应力分布 被引量:1
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作者 李帅 刘桦 +3 位作者 商永慧 刘义琮 赵启航 刘文 《中国组织工程研究》 CAS 北大核心 2025年第5期881-887,共7页
背景:Twin-block矫治器常用于安氏Ⅱ类错[牙合]畸形的矫治,其刺激下颌骨生长的作用机制已得到许多研究证实,但对上颌骨生长的影响尚不清楚。目的:通过有限元法分析安氏Ⅱ类错[牙合]畸形患者佩戴Twin-block矫治器时上颌骨复合体、周围骨... 背景:Twin-block矫治器常用于安氏Ⅱ类错[牙合]畸形的矫治,其刺激下颌骨生长的作用机制已得到许多研究证实,但对上颌骨生长的影响尚不清楚。目的:通过有限元法分析安氏Ⅱ类错[牙合]畸形患者佩戴Twin-block矫治器时上颌骨复合体、周围骨缝及上颌牙列的应力分布。方法:选择在山东省康复大学青岛医院/青岛市市立医院口腔正畸科进行正畸治疗的安氏Ⅱ类错[牙合]畸形患者1例,测量患者佩戴Twin-block矫治器时的咬合力数据,采集其锥形束CT数据,建立包含上颌骨复合体、周边各骨缝、Twin-block矫治器及上颌牙列在内的有限元模型,通过ABAQUS软件模拟患者戴入Twin-block时上颌骨、骨缝及上颌牙列的应力分布与位移。结果与结论:①上颌前牙受到的等效应力明显小于后牙,两侧牙齿的最大等效应力分别为4.7975 MPa和8.7161 MPa,均位于第一前磨牙处;最大位移呈现在两侧上颌切牙处,分别为0.0805 mm和0.0810 mm;②骨缝的最大等效应力为1.284 MPa,主要集中在两侧翼腭缝及额颌缝,其余骨缝受力情况几乎无差异;骨缝的最大位移为0.07 mm,其中翼腭缝的位移量最大,其次是额颌缝;③上颌骨复合体受到的最大等效应力为27.18 MPa,主要集中在上颌骨前面梨状孔两侧、鼻额缝周边及颚骨后部翼腭缝附近;上颌骨的最大位移值为0.07 mm,主要集中于上颌牙槽骨;④结果显示,咬合力通过Twin-block矫治器作用于上颌骨复合体,导致上颌骨顺时针旋转、牙合平面变陡,应采取相应措施补偿这种趋势,例如建牙合过程中考虑上颌磨牙伸长、下颌磨牙压低,不仅能够将牙合平面整平,同时有利于下颌前伸,这将进一步提高Ⅱ类错[牙合]正畸治疗效果。 展开更多
关键词 错牙合畸形 组织构建 骨组织工程 TWIN-block矫治器 功能矫治 有限元分析
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Midpoint transverse process to pleura block for postoperative analgesia following laparoscopic renal cyst decortication:Two case reports
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作者 Wei-Jie He Wen-Xing Xu +4 位作者 Xu-Dong Zhang Yue Chen Shu-Ying He Xian-Qin Wei Xiao-Lan Huang 《World Journal of Clinical Cases》 SCIE 2024年第18期3629-3635,共7页
BACKGROUND The midpoint transverse process to pleura(MTP)block,a novel technique for thoracic paravertebral block(TPVB),was first employed in laparoscopic renal cyst decortication.CASE SUMMARY Thoracic paravertebral n... BACKGROUND The midpoint transverse process to pleura(MTP)block,a novel technique for thoracic paravertebral block(TPVB),was first employed in laparoscopic renal cyst decortication.CASE SUMMARY Thoracic paravertebral nerve block is frequently employed for perioperative analgesia during laparoscopic cyst decortication.To address safety concerns associated with TPVBs,we administered MTP blocks in two patients prior to administering general anesthesia for laparoscopic cyst decortication.The MTP block was performed at the T9 level under ultrasound guidance,with 20 mL of 0.5%ropivacaine injected.Reduced sensation to cold and pinprick was observed from the T8 to T11 dermatome levels.Immediately postoperative Numeric Pain Rating Scale scores were 0/10 at rest and on movement,with none exceeding a mean 24 h numeric rating scale>3.CONCLUSION MTP block was effective technique for providing postoperative analgesia for patients undergoing laparoscopic renal cyst decortication. 展开更多
关键词 Midpoint transverse process to pleura block Laparoscopic renal cyst decortication PAIN ANALGESIA Case report
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A Lightweight Multiscale Feature Fusion Network for Solar Cell Defect Detection
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作者 Xiaoyun Chen Lanyao Zhang +3 位作者 Xiaoling Chen Yigang Cen Linna Zhang Fugui Zhang 《Computers, Materials & Continua》 SCIE EI 2025年第1期521-542,共22页
Solar cell defect detection is crucial for quality inspection in photovoltaic power generation modules.In the production process,defect samples occur infrequently and exhibit random shapes and sizes,which makes it cha... Solar cell defect detection is crucial for quality inspection in photovoltaic power generation modules.In the production process,defect samples occur infrequently and exhibit random shapes and sizes,which makes it challenging to collect defective samples.Additionally,the complex surface background of polysilicon cell wafers complicates the accurate identification and localization of defective regions.This paper proposes a novel Lightweight Multiscale Feature Fusion network(LMFF)to address these challenges.The network comprises a feature extraction network,a multi-scale feature fusion module(MFF),and a segmentation network.Specifically,a feature extraction network is proposed to obtain multi-scale feature outputs,and a multi-scale feature fusion module(MFF)is used to fuse multi-scale feature information effectively.In order to capture finer-grained multi-scale information from the fusion features,we propose a multi-scale attention module(MSA)in the segmentation network to enhance the network’s ability for small target detection.Moreover,depthwise separable convolutions are introduced to construct depthwise separable residual blocks(DSR)to reduce the model’s parameter number.Finally,to validate the proposed method’s defect segmentation and localization performance,we constructed three solar cell defect detection datasets:SolarCells,SolarCells-S,and PVEL-S.SolarCells and SolarCells-S are monocrystalline silicon datasets,and PVEL-S is a polycrystalline silicon dataset.Experimental results show that the IOU of our method on these three datasets can reach 68.5%,51.0%,and 92.7%,respectively,and the F1-Score can reach 81.3%,67.5%,and 96.2%,respectively,which surpasses other commonly usedmethods and verifies the effectiveness of our LMFF network. 展开更多
关键词 Defect segmentation multi-scale feature fusion multi-scale attention depthwise separable residual block
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3种不同类型Twin-block矫治器对前牙应力分布和位移的影响
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作者 李星雨 张春艳 +8 位作者 李希贝 黄文莉 于少洋 杨文科 张映玥 郭骏 阎潇 张强 袁晓 《医用生物力学》 北大核心 2025年第4期844-850,共7页
目的 研究3种不同类型Twin-block矫治器对前牙、牙周膜及牙槽骨应力及位移的影响。方法 构建上下颌骨、关节盘、牙列及牙周膜的三维有限元模型。3组不同类型Twin-block矫治器的有限元模型分别为传统Twin-block矫治器、带切牙帽Twin-bloc... 目的 研究3种不同类型Twin-block矫治器对前牙、牙周膜及牙槽骨应力及位移的影响。方法 构建上下颌骨、关节盘、牙列及牙周膜的三维有限元模型。3组不同类型Twin-block矫治器的有限元模型分别为传统Twin-block矫治器、带切牙帽Twin-block矫治器、改良隐形Twin-block矫治器(clear twin-block aligner, CTBA)。所有类型矫治器的斜面角度均为70°,双侧分别加载200 N垂直于斜面的力。利用有限元方法分析前牙的应力分布与位移差异。结果 3种不同类型Twin-block矫治器均会导致上前牙舌倾及下前牙唇倾。CTBA组上前牙舌向位移及应力最大,最大应力为30.6 MPa,而下前牙唇向位移及应力最小,位移约为0.02 mm。同时CTBA组下前牙、牙周膜及牙槽骨所受等效应力在3组中最低,而传统Twin-block矫治器组最高。结论 在使用传统Twin-block矫治器治疗安氏Ⅱ类错[牙合]时,无论有无切牙帽,均会导致下前牙的唇倾;而与传统Twin-block矫治器相比,CTBA可减少对下前牙、牙槽骨、牙周膜应力和位移的影响,进而减小下前牙的牙周风险,但需注意上前牙舌向位移带来的舌倾效应。 展开更多
关键词 TWIN-block矫治器 功能矫治 隐形矫治器 安氏Ⅱ类错[牙合] 前牙
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Enhancing postoperative pain control by surgically-initiated rectus sheath block in abdominal aortic aneurysm open repair: A case report
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作者 Kuan-Hua Chen Ming-Yuan Kang +2 位作者 Yi-Ting Chang Sheng-Yang Huang Yung-Szu Wu 《World Journal of Clinical Cases》 SCIE 2025年第6期41-47,共7页
BACKGROUND Abdominal aortic aneurysm(AAA)repair often involves significant postoperative pain,traditionally managed with systemic opioids,which can cause undesirable side effects.This case report explores the novel us... BACKGROUND Abdominal aortic aneurysm(AAA)repair often involves significant postoperative pain,traditionally managed with systemic opioids,which can cause undesirable side effects.This case report explores the novel use of a surgically-initiated rectus sheath block with a catheter-over-needle assembly for pain management in AAA repair.CASE SUMMARY A 67-year-old female with hypertension and previous aortic dissection underwent elective open repair of an infrarenal AAA,which had grown from 3.4 cm to 4.3 cm over 14 months.A rectus sheath block was initiated surgically for postoperative pain control.The patient reported low pain scores and did not require systemic intravenous opioids,enabling early ambulation and discharge on postoperative day seven without complications.By preventing complications of systemic opi-oids,the method indicating a promising direction for postoperative pain management in major vascular surgeries.CONCLUSION Surgically-initiated rectus sheath block as a valuable tool for managing postoperative pain in AAA repair. 展开更多
关键词 Abdominal aortic aneurysm Postoperative pain management Rectus sheath block Surgical anesthesia Opioid-sparing techniques Case report
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The A_(α)-spectral Radius of Block Graphs with Given Dissociation Number
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作者 HUANG Peng LI Jianxi 《数学进展》 北大核心 2025年第4期696-708,共13页
For a simple graph G,let A(G)and D(G)be the adjacency matrix and the diagonal degree matrix of G,respectively.[Appl.Anal.Discrete Math.,2017,11(1):81-107]defined the matrix A_(α)(G)of G as A_(α)(G)=αD(G)(1-α)A(G)... For a simple graph G,let A(G)and D(G)be the adjacency matrix and the diagonal degree matrix of G,respectively.[Appl.Anal.Discrete Math.,2017,11(1):81-107]defined the matrix A_(α)(G)of G as A_(α)(G)=αD(G)(1-α)A(G),α∈[0,1].The Aa-spectral radius is the largest eigenvalue of A_(α)(G).Let G_(n,β) be the set graphs with order n and dissociation numberβ.In this paper,we identify the b with maximal A_(α)-spectral radius among all graphs in G_(n,β). 展开更多
关键词 A_(α)-spectral radius block graph SIZE dissociation number
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Block sparse compressed sensing with frames:Null space property and l_(2)/l_(q)(0
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作者 WU Fengong ZHONG Penghong QIN Yuehai 《中山大学学报(自然科学版)(中英文)》 北大核心 2025年第3期173-182,共10页
This paper explores the recovery of block sparse signals in frame-based settings using the l_(2)/l_(q)-synthesis technique(0<q≤1).We propose a new null space property,referred to as block D-NSP_(q),which is based ... This paper explores the recovery of block sparse signals in frame-based settings using the l_(2)/l_(q)-synthesis technique(0<q≤1).We propose a new null space property,referred to as block D-NSP_(q),which is based on the dictionary D.We establish that matrices adhering to the block D-NSP_(q)condition are both necessary and sufficient for the exact recovery of block sparse signals via l_(2)/l_(q)-synthesis.Additionally,this condition is essential for the stable recovery of signals that are block-compressible with respect to D.This D-NSP_(q)property is identified as the first complete condition for successful signal recovery using l_(2)/l_(q)-synthesis.Furthermore,we assess the theoretical efficacy of the l2/lq-synthesis method under conditions of measurement noise. 展开更多
关键词 Compressed sensing block sparse l2/lq-synthesis method null space property
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Bayesian network structure learning by dynamic programming algorithm based on node block sequence constraints
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作者 Chuchao He Ruohai Di +1 位作者 Bo Li Evgeny Neretin 《CAAI Transactions on Intelligence Technology》 2024年第6期1605-1622,共18页
The use of dynamic programming(DP)algorithms to learn Bayesian network structures is limited by their high space complexity and difficulty in learning the structure of large-scale networks.Therefore,this study propose... The use of dynamic programming(DP)algorithms to learn Bayesian network structures is limited by their high space complexity and difficulty in learning the structure of large-scale networks.Therefore,this study proposes a DP algorithm based on node block sequence constraints.The proposed algorithm constrains the traversal process of the parent graph by using the M-sequence matrix to considerably reduce the time consumption and space complexity by pruning the traversal process of the order graph using the node block sequence.Experimental results show that compared with existing DP algorithms,the proposed algorithm can obtain learning results more efficiently with less than 1%loss of accuracy,and can be used for learning larger-scale networks. 展开更多
关键词 Bayesian network(BN) dynamic programming(DP) node block sequence strongly connected component(SCC) structure learning
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A Nonlinear Multi-Scale Interaction Model for Atmospheric Blocking:A Tool for Exploring the Impact of Changing Climate on Mid-to-High Latitude Weather Extremes 被引量:1
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作者 Dehai LUO Wenqi ZHANG Binhe LUO 《Advances in Atmospheric Sciences》 2025年第10期2018-2035,共18页
A nonlinear multi-scale interaction(NMI)model was proposed and developed by the first author for nearly 30 years to represent the evolution of atmospheric blocking.In this review paper,we first review the creation and... A nonlinear multi-scale interaction(NMI)model was proposed and developed by the first author for nearly 30 years to represent the evolution of atmospheric blocking.In this review paper,we first review the creation and development of the NMI model and then emphasize that the NMI model represents a new tool for identifying the basic physics of how climate change influences mid-to-high latitude weather extremes.The building of the NMI model took place over three main periods.In the 1990s,a nonlinear Schr?dinger(NLS)equation model was presented to describe atmospheric blocking as a wave packet;however,it could not depict the lifetime(10-20 days)of atmospheric blocking.In the 2000s,we proposed an NMI model of atmospheric blocking in a uniform basic flow by making a scale-separation assumption and deriving an eddyforced NLS equation.This model succeeded in describing the life cycle of atmospheric blocking.In the 2020s,the NMI model was extended to include the impact of a changing climate mainly by altering the basic zonal winds and the magnitude of the meridional background potential vorticity gradient(PVy).Model results show that when PVy is smaller,blocking has a weaker dispersion and a stronger nonlinearity,so blocking can be more persistent and have a larger zonal scale and weaker eastward movement,thus favoring stronger weather extremes.However,when PVy is much smaller and below a critical threshold under much stronger winter Arctic warming of global warming,atmospheric blocking becomes locally less persistent and shows a much stronger westward movement,which acts to inhibit local cold extremes.Such a case does not happen in summer under global warming because PVy fails to fall below the critical threshold.Thus,our theory indicates that global warming can render summer-blocking anticyclones and mid-to-high latitude heatwaves more persistent,intense,and widespread. 展开更多
关键词 nonlinear Schrödinger equation nonlinear multi-scale interaction model of atmospheric blocking meridional background potential vorticity gradient climate change mid-to-high latitude weather extremes
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Differential-Linear Attacks on Ballet Block Cipher
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作者 ZHOU Yu CHEN Si-Wei +2 位作者 XU Sheng-Yuan XIANG Ze-Jun ZENG Xiang-Yong 《密码学报(中英文)》 北大核心 2025年第2期469-488,共20页
Ballet is one of the finalists of the block cipher project in the 2019 National Cryptographic Algorithm Design Competition.This study aims to conduct a comprehensive security evaluation of Ballet from the perspective ... Ballet is one of the finalists of the block cipher project in the 2019 National Cryptographic Algorithm Design Competition.This study aims to conduct a comprehensive security evaluation of Ballet from the perspective of differential-linear(DL)cryptanalysis.Specifically,we present an automated search for the DL distinguishers of Ballet based on MILP/MIQCP.For the versions with block sizes of 128 and 256 bits,we obtain 16 and 22 rounds distinguishers with estimated correlations of 2^(-59.89)and 2^(-116.80),both of which are the publicly longest distinguishers.In addition,this study incorporates the complexity information of key-recovery attacks into the automated model,to search for the optimal key-recovery attack structures based on DL distinguishers.As a result,we mount the key-recovery attacks on 16-round Ballet-128/128,17-round Ballet-128/256,and 21-round Ballet-256/256.The data/time complexities for these attacks are 2^(108.36)/2^(120.36),2^(115.90)/2^(192),and 2^(227.62)/2^(240.67),respectively. 展开更多
关键词 Ballet block cipher differential-linear(DL)cryptanalysis MILP/MIQCP distinguisher key-recovery attacks
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Enhanced Cutaneous Melanoma Segmentation in Dermoscopic Images Using a Dual U-Net Framework with Multi-Path Convolution Block Attention Module and SE-Res-Conv
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作者 Kun Lan Feiyang Gao +2 位作者 Xiaoliang Jiang Jianzhen Cheng Simon Fong 《Computers, Materials & Continua》 2025年第9期4805-4824,共20页
With the continuous development of artificial intelligence and machine learning techniques,there have been effective methods supporting the work of dermatologist in the field of skin cancer detection.However,object si... With the continuous development of artificial intelligence and machine learning techniques,there have been effective methods supporting the work of dermatologist in the field of skin cancer detection.However,object significant challenges have been presented in accurately segmenting melanomas in dermoscopic images due to the objects that could interfere human observations,such as bubbles and scales.To address these challenges,we propose a dual U-Net network framework for skin melanoma segmentation.In our proposed architecture,we introduce several innovative components that aim to enhance the performance and capabilities of the traditional U-Net.First,we establish a novel framework that links two simplified U-Nets,enabling more comprehensive information exchange and feature integration throughout the network.Second,after cascading the second U-Net,we introduce a skip connection between the decoder and encoder networks,and incorporate a modified receptive field block(MRFB),which is designed to capture multi-scale spatial information.Third,to further enhance the feature representation capabilities,we add a multi-path convolution block attention module(MCBAM)to the first two layers of the first U-Net encoding,and integrate a new squeeze-and-excitation(SE)mechanism with residual connections in the second U-Net.To illustrate the performance of our proposed model,we conducted comprehensive experiments on widely recognized skin datasets.On the ISIC-2017 dataset,the IoU value of our proposed model increased from 0.6406 to 0.6819 and the Dice coefficient increased from 0.7625 to 0.8023.On the ISIC-2018 dataset,the IoU value of proposed model also improved from 0.7138 to 0.7709,while the Dice coefficient increased from 0.8285 to 0.8665.Furthermore,the generalization experiments conducted on the jaw cyst dataset from Quzhou People’s Hospital further verified the outstanding segmentation performance of the proposed model.These findings collectively affirm the potential of our approach as a valuable tool in supporting clinical decision-making in the field of skin cancer detection,as well as advancing research in medical image analysis. 展开更多
关键词 Dual U-Net skin lesion segmentation squeeze-and-excitation modified receptive field block multi-path convolution block attention module
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A knowledge-data dually driven paradigm for accurate identification of key blocks in complex rock slopes
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作者 Xiaoyu Qi Han Meng +2 位作者 Nengxiong Xu Gang Mei Jianbing Peng 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第6期3726-3746,共21页
Accurate identification and effective support of key blocks are crucial for ensuring the stability and safety of rock slopes.The number of structural planes and rock blocks were reduced in previous studies.This impair... Accurate identification and effective support of key blocks are crucial for ensuring the stability and safety of rock slopes.The number of structural planes and rock blocks were reduced in previous studies.This impairs the ability to characterize complex rock slopes accurately and inhibits the identification of key blocks.In this paper,a knowledge-data dually driven paradigm for accurate identification of key blocks in complex rock slopes is proposed.Our basic idea is to integrate key block theory into data-driven models based on finely characterizing structural features to identify key blocks in complex rock slopes accurately.The proposed novel paradigm consists of(1)representing rock slopes as graph-structured data based on complex systems theory,(2)identifying key nodes in the graph-structured data using graph deep learning,and(3)mapping the key nodes of graph-structured data to corresponding key blocks in the rock slope.Verification experiments and real-case applications are conducted by the proposed method.The verification results demonstrate excellent model performance,strong generalization capability,and effective classification results.Moreover,the real case application is conducted on the northern slope of the Yanqianshan Iron Mine.The results show that the proposed method can accurately identify key blocks in complex rock slopes,which can provide a decision-making basis and rational recommendations for effective support and instability prevention of rock slopes,thereby ensuring the stability of rock engineering and the safety of life and property. 展开更多
关键词 Key blocks identification Rock slope stability Key block theory Knowledge-data dually driven Graph deep learning
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Diagnosis and treatment of pupillary block glaucoma following implantable collamer lens surgery:a case report
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作者 Bei-Bei Wang Ying-Ying Zou +2 位作者 Dong-Mei Liu Fang Sha Hong-Sheng Bi 《International Journal of Ophthalmology(English edition)》 2025年第6期1173-1177,共5页
Dear Editor,The latest Visian implantable collamer lens(ICL)with a central port design(Aquaport;model V4c)obviates the necessity for preoperative laser iridotomy or intraoperative iridectomy by allowing the free flow ... Dear Editor,The latest Visian implantable collamer lens(ICL)with a central port design(Aquaport;model V4c)obviates the necessity for preoperative laser iridotomy or intraoperative iridectomy by allowing the free flow of the aqueous humor between the sides of the intraocular lens.The design of Aquaport can also eliminate the complications associated with iridotomy and iridectomy.Therefore,the V4c ICL has the potential to significantly reduce the risk of pupillary block compared to its predecessors. 展开更多
关键词 implantable collamer lens surgery laser iridotomy Visian ICL visian implantable collamer lens icl diagnosis pupillary block glaucoma pupillary block aqueous humor
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Twin-block功能矫治器与肌激动器对安氏Ⅱ类下颌后缩的矫治效果对比 被引量:1
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作者 杨宇虹 张静 +2 位作者 孙留振 刘耀冉 姜龙龙 《临床医学工程》 2025年第3期279-282,共4页
目的 对比分析Twin-block功能矫治器与肌激动器在安氏Ⅱ类下颌后缩患者矫治中的应用效果。方法 回顾性分析2020年1月至2024年1月我院收治的80例安氏Ⅱ类下颌后缩患者的临床资料,将采用Twin-block功能矫治器矫治的40例患者设为Twin-block... 目的 对比分析Twin-block功能矫治器与肌激动器在安氏Ⅱ类下颌后缩患者矫治中的应用效果。方法 回顾性分析2020年1月至2024年1月我院收治的80例安氏Ⅱ类下颌后缩患者的临床资料,将采用Twin-block功能矫治器矫治的40例患者设为Twin-block组,采用肌激动器矫治的40例患者设为肌激组。比较两组的矫治效果以及矫治8个月后的上气道矢状径[硬腭平面上气道矢状径(AP-hp)、软腭尖平面上气道矢状径(AP-sp)、会厌尖平面上气道矢状径(AP-te)]和舌骨位置[舌骨点至后鼻棘点距离(H-PNS)、舌骨点至锥前平面距离(H-CVP)、舌骨点至下颌平面距离(H-MP)、舌骨点至腭平面距离(H-PP)],并比较两组患者的主观感受情况。结果 Twin-block组的矫治总有效率(90.00%)与肌激组(80.00%)对比,差异无统计学意义(P>0.05)。矫治8个月后,Twin-block组的AP-hp、 AP-sp、 AP-te、 H-PNS、 H-CVP、 H-MP、 H-PP均大于肌激组(P <0.05);Twin-block组的佩戴顺利、舒适性、依从性和美观度评分均低于肌激组(P <0.05)。结论 Twin-block功能矫治器与肌激动器用于矫治安氏Ⅱ类下颌后缩的效果相当,但Twin-block功能矫治器能更有效地矫正安氏Ⅱ类下颌后缩患者的舌骨位置,改善患者的气道形态,而肌激动器矫治患者的主观感受更好。 展开更多
关键词 安氏Ⅱ类下颌后缩 TWIN-block功能矫治器 肌激动器 上气道矢状径 舌骨位置 主观感受
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Twin Block双期矫治安氏Ⅱ类1分类伴口呼吸错[牙合]畸形的临床研究
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作者 周玲 周慧 +1 位作者 胡关举 郑娟珠 《中国医疗美容》 2025年第7期124-129,共6页
目的探讨扩弓Twin Block联合直丝弓矫治技术治疗青少年安氏Ⅱ类1分类伴口呼吸错[牙合]畸形的临床疗效。方法选取2023年3月至2025年3月在珠海市口腔医院完成正畸治疗的安氏Ⅱ类1分类伴口呼吸错青少年患者60例,分为两组。治疗组采用扩弓、... 目的探讨扩弓Twin Block联合直丝弓矫治技术治疗青少年安氏Ⅱ类1分类伴口呼吸错[牙合]畸形的临床疗效。方法选取2023年3月至2025年3月在珠海市口腔医院完成正畸治疗的安氏Ⅱ类1分类伴口呼吸错青少年患者60例,分为两组。治疗组采用扩弓、Twin Block与直丝弓固定矫治。对照组行直丝弓固定矫治。比较两组治疗前后上下颌骨、牙齿与上气道相关指标的变化。结果两组治疗后SNA、ANB、U1-SN减小,Go-Co、Z-Angle、V总、S总、Smin增加(P<0.05)。治疗组SNB增加,ANB、Go-Co、S总改善较对照组明显(P<0.05)。结论扩弓Twin Block双期矫治青少年安氏Ⅱ类1分类伴口呼吸错[牙合]畸形可促进下颌生长,减少牙性代偿,改善上气道狭窄,疗效显著。 展开更多
关键词 Twin block 扩弓器 双期矫治 直丝弓矫治技术 安氏Ⅱ类1分类错[牙合] 口呼吸
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