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A Wrapping Encryption Based on Double Randomness Mechanism
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作者 Yi-Li Huang Fang-Yie Leu +2 位作者 Ruey-Kai Sheu Jung-Chun Liu Chi-Jan Huang 《Computers, Materials & Continua》 SCIE EI 2023年第10期1143-1164,共22页
Currently,data security mainly relies on password(PW)or system channel key(SKCH)to encrypt data before they are sent,no matter whether in broadband networks,the 5th generation(5G)mobile communications,satellite commun... Currently,data security mainly relies on password(PW)or system channel key(SKCH)to encrypt data before they are sent,no matter whether in broadband networks,the 5th generation(5G)mobile communications,satellite communications,and so on.In these environments,a fixed password or channel key(e.g.,PW/SKCH)is often adopted to encrypt different data,resulting in security risks since thisPW/SKCH may be solved after hackers collect a huge amount of encrypted data.Actually,the most popularly used security mechanism Advanced Encryption Standard(AES)has its own problems,e.g.,several rounds have been solved.On the other hand,if data protected by the same PW/SKCH at different time points can derive different data encryption parameters,the system’s security level will be then greatly enhanced.Therefore,in this study,a security scheme,named Wrapping Encryption Based on Double Randomness Mechanism(WEBDR),is proposed by integrating a password key(or a system channel key)and an Initialization Vector(IV)to generate an Initial Encryption Key(IEK).Also,an Accumulated Shifting Substitution(ASS)function and a three-dimensional encryption method are adopted to produce a set of keys.Two randomness encryption mechanisms are developed.The first generates system sub-keys and calculates the length of the first pseudo-random numbers by employing IEK for providing subsequent encryption/decryption.The second produces a random encryption key and a sequence of internal feedback codes and computes the length of the second pseudo-random numbers for encrypting delivered messages.A wrapped mechanism is further utilized to pack a ciphertext file so that a wrapped ciphertext file,rather than the ciphertext,will be produced and then transmitted to its destination.The findings are as follows.Our theoretic analyses and simulations demonstrate that the security of the WEBDR in cloud communication has achieved its practical security.Also,AES requires 176 times exclusive OR(XOR)operations for both encryption and decryption,while the WEBDR consumes only 3 operations.That is why the WEBDR is 6.7∼7.09 times faster than the AES,thus more suitable for replacing the AES to protect data transmitted between a cloud system and its users. 展开更多
关键词 Initial encryption key accumulated shifting substitution three-dimensional operation wrapped ciphertext file
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“Wrapping the gastroduodenal artery stump” during pancreatoduodenectomy reduced the stump hemorrhage incidence after operation 被引量:7
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作者 Chang Xu Xinwei Yang +4 位作者 Xiangji Luo Feng Shen Mengchao Wu Weifeng Tan Xiaoqing Jiang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2014年第3期299-308,共10页
Objective: After pancreaticoduodenectomy (PD), the postoperative gastroduodenal artery stump (GDAS) hemorrhage is one of the most serious complications. The purpose of this study is to determine whether wrapping ... Objective: After pancreaticoduodenectomy (PD), the postoperative gastroduodenal artery stump (GDAS) hemorrhage is one of the most serious complications. The purpose of this study is to determine whether wrapping the GDAS during PD could decrease the postoperative GDAS hemorrhage incidence. Methods: A retrospective review involving 280 patients who underwent PD from 2005 to 2012 was performed. Wrapping the GDAS during PD was defined as "Wrapping the GDAS using the teres hepatis ligamentum during PD". A total of 140 patients accepted the "wrapping" procedure (wrapping group). The other 140 patients didn't apply the procedure (non-wrapping group). Age, sex, preoperative data, estimated intraoperative blood loss, postoperative complications, pathologic parameters and hospitalization time were compared between two groups. ResultsI There were no significant differences in patient characteristics between two groups. After wrapping, the incidence of postoperative GDAS bleeding decreased significantly (1/140 vs. 9/140, P=0.01). The rates of the other complications (such as intra-abdominal infection pancreatic fistula, billiary fistula, gastrointestinal bleeding, et aL) showed no significant differences. Conclusions: Wrapping the GDAS during PD significantly reduced the postoperative GDAS hemorrhage incidence. And the "wrapping" had no obvious influence on other complications. 展开更多
关键词 Pancreaticoduodenectom (PD) wrapping the gastroduodenal artery stump (GDAS) GDAShemorrhage
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Auricular cartilage versus donor sclera as a wrapping of hydroxyapatite orbital implants
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作者 Ying-Jie Ma Xiu-Ying Zhu +3 位作者 Ben Chen Yan-Yan Lin Jia Liu Xi Chen 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2021年第3期436-441,共6页
AIM: To retrospectively compare postoperative outcomes after primary enucleation and placement of a hydroxyapatite(HA) implant without wrapping, wrapped with auricular cartilage or donor sclera. METHODS: Medical recor... AIM: To retrospectively compare postoperative outcomes after primary enucleation and placement of a hydroxyapatite(HA) implant without wrapping, wrapped with auricular cartilage or donor sclera. METHODS: Medical records of patients presented as intraocular tumor or severe ocular injury were identified from the electronic medical record system. Cases underwent enucleation and HA orbital implantation were enrolled in this study and were divided into 3 groups according to the wrapping material of HA implant. Cases with autogenous cartilage caps were enrolled in group A(n=11), with donor sclera caps in group B(n=12), and without any wrapping material in group C(n=9). Follow-ups were set at 1, 2 wk, 1, 3, 6, and 12 mo after surgery.RESULTS: Altogether 32 cases finished the followup and were enrolled in this study. Three cases(27.27%) in group A, 4 cases(33.33%) in group B, and 4 cases(44.44%) in group C developed one complication each after surgery. In group A, no HA exposure occurred, but conjunctival inclusion cyst occurred in one and severe conjunctive chemosis in two cases. In group B, one HA exposure occurred, conjunctive inclusion cysts occurred in one, severe conjunctive chemosis occurred in one, and conjunctival granuloma occurred in one case. In group C, one HA exposure occurred, severe conjunctive chemosis occurred in two cases, and conjunctival granuloma occurred in one case. The case of exposure of none-wrapped implant was noted in the first 6 mo after placement of the orbital implant. The case of exposure of donor sclerawrapped implant was noted at the 12 mo after placement of the orbital implant. Both exposure cases were treated successfully with conservative treatment.CONCLUSION: With low incidence of implant exposure and mild complications, auricular cartilage can be a good choice of alternative wrapping material of orbit implant with satisfied outcome. 展开更多
关键词 hydroxyapatite orbital implants wrapping auricular cartilage donor sclera COMPLICATION
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Multi-baseline phase unwrapping algorithm for INSAR
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作者 Xianming Xie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第3期417-425,共9页
A novel multi-baseline phase unwrapping algorithm based on the unscented particle filter for interferometric synthetic aperture radar (INSAR) technology application is proposed. The proposed method is not constraine... A novel multi-baseline phase unwrapping algorithm based on the unscented particle filter for interferometric synthetic aperture radar (INSAR) technology application is proposed. The proposed method is not constrained by the nonlinearity of the problem and is independent of noise statistics, and performs noise eliminating and phase unwrapping at the same time by combining with an unscented particle filter with a path-following strategy and an omni-directional local phase slope estimator. Results obtained from multi-baseline synthetic data and single-baseline real data show the performance of the proposed method. 展开更多
关键词 interferometric aperture radar (INSAR) phase un- wrapping unscented particle filter.
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Online Shape Dynamic Wrapping Angle Compensation Model of Cold Strip 被引量:11
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作者 YANG Li-po YU Bing-qiang YU Hua-xin 《Journal of Iron and Steel Research(International)》 SCIE EI CAS CSCD 2011年第7期28-32,共5页
In specific condition, when wrapping angle of cold rolling strip covering surface of shape detecting roll dynamically changes, online radial compression of the shape detecting roll is changed too, and it seriously aff... In specific condition, when wrapping angle of cold rolling strip covering surface of shape detecting roll dynamically changes, online radial compression of the shape detecting roll is changed too, and it seriously affects online shape detecting precision of cold strip. Based on the latest intelligent shape meter developed by Yanshan University, using PSO-BP neural network and actual working condition datum, the cold strip online dynamic wrapping angle compensation model is established, and successfully applied in 1250 mm 6-high cold mill, remarkable results are achieved. The error between calculated values and measured values of total tensions is within 3 % 展开更多
关键词 cold roiling strip shape detecting wrapping angle COMPENSATION shape meter cold mill
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Study on round rice straw bale wrapping silage technology and facilities 被引量:5
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作者 Liqiao Li Defu Wang Xing Yang 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2018年第4期88-95,共8页
Specific to problems of the existing round bale wrapping machine in China,such as small application scope and failing to satisfy the wrapping demands of round bales of different specifications,a tumbler-type round bal... Specific to problems of the existing round bale wrapping machine in China,such as small application scope and failing to satisfy the wrapping demands of round bales of different specifications,a tumbler-type round bale wrapping machine based on wrapping silage with stretch film was designed.By theoretical analysis and preliminary experiments of the corresponding wrapping process,revolving speed of tumbler,speed ratio between tumbler and carrier rollers,and pre-load force of stretch film were determined as experimental factors,while wrapping time and consumption of stretch film per unit mass of round bale were determined as evaluation indexes.Furthermore,quadratic regression orthogonal rotational combination experimental design was adopted to carry out the wrapping experiment.The regression models were set up,and influencing rules of experimental factors on evaluation indexes were also analyzed.The optimal parameter combination scheme was revolving speed of tumbler of 31-32 r/min,speed ratio between tumbler and carrier rollers of 2.6,and pre-load force of stretch film of 20-22 N.Under such a circumstance,the corresponding wrapping time required was 37.7-38.9 s and consumption of stretch film per unit mass of round bale was 3.21-3.46 kg/t.The predicted values and the measured values of evaluation indexes basically coincided with each other and the relative error fell below 5%,which indicated that both the optimized regression models acquired through the wrapping experiment and the relevant parameter optimization results were reliable.To guarantee the quality of rice straw silage,the round bale should be wrapped by no less than five layers of stretch films through the utilization of the tumbler-type round bale wrapping machine.The study results could be used as references for research and development of the round bale wrapping machine. 展开更多
关键词 round bale SILAGE wrapping machine tumbler-type analysis experiment
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A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair
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作者 Simeon C.Daeschler Katelyn J.W.So +7 位作者 Konstantin Feinberg Marina Manoraj Jenny Cheung Jennifer Zhang Kaveh Mirmoeini JPaul Santerre Tessa Gordon Gregory HBorschel 《Neural Regeneration Research》 SCIE CAS 2025年第1期291-304,共14页
Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong disability.Currently,there are no FDA-approved therapies a... Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong disability.Currently,there are no FDA-approved therapies available to promote nerve regeneration.Tacrolimus accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve surgery.The authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug exposure.Tacrolimus is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 days.Size and drug loading are adjustable for applications in small and large caliber nerves,and the wrap degrades within 120 days into biocompatible byproducts.Tacrolimus released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic delivery.Given its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery. 展开更多
关键词 BIODEGRADABLE local drug delivery nerve injury nerve regeneration nerve wrap TACROLIMUS
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Blade Wrap Angle Impact on Centrifugal Pump Performance:Entropy Generation and Fluid-Structure Interaction Analysis
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作者 Hayder Kareem Sakran Mohd Sharizal Abdul Aziz Chu Yee Khor 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期109-137,共29页
The centrifugal pump is a prevalent power equipment widely used in different engineering patterns,and the impeller blade wrap angle significantly impacts its performance.A numerical investigation was conducted to anal... The centrifugal pump is a prevalent power equipment widely used in different engineering patterns,and the impeller blade wrap angle significantly impacts its performance.A numerical investigation was conducted to analyze the influence of the blade wrap angle on flow characteristics and energy distribution of a centrifugal pump evaluated as a low specific speed with a value of 69.This study investigates six impellermodels that possess varying blade wrap angles(95°,105°,115°,125°,135°,and 145°)that were created while maintaining the same volute and other geometrical characteristics.The investigation of energy loss was conducted to evaluate the values of total and entropy generation rates(TEG,EGR).The fluid-structure interaction was considered numerically using the software tools ANSYS Fluent and ANSYSWorkbench.The elastic structural dynamic equation was used to estimate the structural response,while the shear stress transport k–ωturbulence model was utilized for the fluid domain modeling.The findings suggest that the blade wrap angle has a significant influence on the efficiency of the pump.The impeller featuring a blade wrap angle of 145°exhibits higher efficiency,with a notable increase of 3.76%relative to the original model.Variations in the blade wrap angle impact the energy loss,shaft power,and pump head.The model with a 145°angle exhibited a maximum equivalent stress of 14.8MPa and a total deformation of 0.084 mm.The results provide valuable insights into the intricate flow mechanism of the centrifugal pump,particularly when considering various blade wrap angles. 展开更多
关键词 Centrifugal pump blade wrap angle entropy generation theory fluid-structure interaction hydraulic performance
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WRAP53与甲状腺乳头状癌患者临床病理特征及预后的关系
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作者 戢楠楠 邓文艺 +1 位作者 陈秀秀 曾越灿 《现代肿瘤医学》 CAS 2024年第1期60-64,共5页
目的:探讨端粒酶新核心亚单位(WD40-encoding RNA antisense to p53,WRAP53)又名端粒酶卡哈尔体蛋白1(telomerase cajal body protein 1,TCAB1)在甲状腺乳头状癌(papillary thyroid carcinoma,PTC)组织中的表达,分析其与患者临床病理特... 目的:探讨端粒酶新核心亚单位(WD40-encoding RNA antisense to p53,WRAP53)又名端粒酶卡哈尔体蛋白1(telomerase cajal body protein 1,TCAB1)在甲状腺乳头状癌(papillary thyroid carcinoma,PTC)组织中的表达,分析其与患者临床病理特征及预后的关系。方法:收集28例PTC患者的癌及癌周正常新鲜组织标本,应用实时荧光定量聚合酶链反应法(quantitative real-time polymerase chain reaction,qPR-PCR)及免疫组织化学法分别检测WRAP53 mRNA及蛋白在PTC及周围正常组织中的表达,收集117例PTC术后患者的临床数据及对应的癌组织的石蜡切片进行免疫组化检测,分析其蛋白表达水平与甲状腺乳头状癌患者的临床病理特征的相关性,最后应用蛋白质表达图谱(The Human Protein Atlas,HPA)数据库探究WRAP53与PTC预后之间的关系。结果:qPR-PCR及免疫组化结果提示WRAP53在PTC中较正常组织高表达(P<0.05)。与WRAP53低表达的PTC患者相比,WRAP53高表达的PTC患者肿瘤直径更长,更易出现淋巴结转移(P<0.05)。HPA数据库显示WRAP53高表达的PTC患者的生存率差于WRAP53低表达的PTC患者(P=0.041)。结论:通过本次研究表明,WRAP53在PTC组织中表达较周围正常组织升高,且其高表达与PTC增殖、淋巴结转移及不良预后相关。WRAP53可能是治疗PTC新的潜在靶点。 展开更多
关键词 甲状腺乳头状癌 WRAP53 TCAB1 临床病理 预后
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基于Geomagic Wrap软件对铣刀盘的点云处理
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作者 夏亚涛 牛晓敏 《机械管理开发》 2023年第4期63-64,67,共3页
Geomagic Wrap软件在逆向工程中经常用于对三维扫描的点云数据进行处理,通过铣刀盘零件的点云处理流程,分析Geomagic Wrap软件对于点云处理精度和有关影响因素,通过选择合理的命令为后续零件点云处理作参考。
关键词 Geomagic Wrap 三维扫描 逆向工程 点云处理 精度
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厦门市700MHz 5G基站干扰隐患及应对措施 被引量:1
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作者 钟奇 俞越 刘伟骏 《中国无线电》 2023年第2期54-55,63,共3页
5G网络对推动我国经济实现高质量发展具有重要意义,700MHz频段是我国5G通信频谱的重要组成部分。本文重点介绍了厦门市700MHz 5G频段受干扰的主要类型,以及利用瑞谱(WRAP)软件仿真干扰台站的影响范围,并提出相关的解决建议。
关键词 700MHz 干扰类型 5G网络 WRAP软件
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Study on Mechanical Properties and Action Mechanism of Leather Industrial Sludge Aggregate Baking-Free Bricks
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作者 Lei Guo Zekun Wang +1 位作者 Lixia Guo Pingping Chen 《Journal of Renewable Materials》 SCIE EI 2023年第1期453-471,共19页
Taking an industrial sludge and its preparation of sludge wrap shell aggregates(WSAs)instead of sand to prepare baking-free brick as the research object,the development law of mechanical properties and the influence m... Taking an industrial sludge and its preparation of sludge wrap shell aggregates(WSAs)instead of sand to prepare baking-free brick as the research object,the development law of mechanical properties and the influence mechanism of macro and micro characteristic parameters of the bricks under different sludge and WSAs replacement rates were studied through the macroscopic mechanical properties test,with the help of nuclear magnetic resonance(NMR),transmission electron microscopy-energy spectrum and other testing technology and pores and cracks analysis system(PCAS)software.The results showed that the compressive strength of each sample decreased with the increase of sludge content.When the sludge content was less than 30%,it was mainly affected by the water-binder ratio.When the sludge content was more than 30%,it was mainly affected by the sludge content.At the age of 7 days,with the increase in replacement rate of WSAs,the compressive strength of the S10 and S30 groups was higher than that of the control group.The compressive strength of the S50 experimental group was 30.38 MPa,and the loss of compressive strength was slight compared with the control group.The water absorption rate of the 28 days S100 experimental group increased by 10.71%compared with the control group.When the content of WSAs was less than 50%,the holes above 0.1μm in the brick can be reduced and transformed into smaller holes,with a decreasing trend of the plane porosity of the brick.The microscopic results of the baking-free brick showed that the three-phase system of WSAs-interface transition area-mortar was poorly bonded and delaminated compared with the gravel aggregate-interface transition area-mortar system,and damage was more likely to occur in the WSAs and interface transition area.The above results show that it is feasible to use sludge and WSAs instead of sand for the preparation of baking-free bricks.This technology not only solves the problem of sludge disposal,but also protects the over-exploitation of mineral resources,and the technology has a broad application prospect and market value. 展开更多
关键词 SLUDGE wrap shell aggregates baking-free brick interface
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“Capsule drape wrap”——a new technology for iridoschisis management during phacoemulsification
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作者 Hui Chen Wan Chen +1 位作者 Yong-Bin Lin Wei-Rong Chen 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第6期984-987,共4页
·AIM: To introduce a new technique for iridoschisis management during phacoemulsification: “capsule drape wrap”.·METHODS: “Capsule drape wrap” technique was used for an 80-year-old man with idiopathic ir... ·AIM: To introduce a new technique for iridoschisis management during phacoemulsification: “capsule drape wrap”.·METHODS: “Capsule drape wrap” technique was used for an 80-year-old man with idiopathic iridoschisis in the right eye during phacoemulsification. The inserted flexible nylon iris hooks to hold anterior capsule in place, the margin of the anterior capsule could act as drape wrap, tracking the fibrillary iris strands firmly from free floating and stabilizing the capsular bags simultaneously. ·RESULTS: The eye with iridoschisis was successfully treated. Iris fibrils remained immobile during the procedure, and despite the severity of iridoschisis, there were no intraoperative complications such as tear of the iris, hyphema, iris prolapse, loss of mydriasis, or rupture of the posterior lens capsule during phacoemulsification. The bestcorrected visual acuity was increased by 0.1(log MAR) 6mo after the surgery.·CONCLUSION: “Capsule drape wrap” for iridoschisis is easily manageable, prevents further disruption to the loose iris fibers and ensures the stability of capsule–iris complex simultaneously, consequently minimizing the risk of surgical complications in phacoemulsification. 展开更多
关键词 “capsule drape wrap”technique iridoschisis management iris hook PHACOEMULSIFICATION
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第二代曲波变换的图像降噪新算法 被引量:6
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作者 都伊林 白直灿 《声学技术》 CSCD 2010年第3期331-335,共5页
Curvelet变换表示曲线奇异函数的异向性及图像边缘时,具有比小波变换更优的表示特性。针对小波图像降噪存在的不足,分析基于wrapping算法的快速离散曲波变换的特点,提出结合循环平移、厄尔迭代方法和蒙特卡洛阈值规则的新消噪方法。该... Curvelet变换表示曲线奇异函数的异向性及图像边缘时,具有比小波变换更优的表示特性。针对小波图像降噪存在的不足,分析基于wrapping算法的快速离散曲波变换的特点,提出结合循环平移、厄尔迭代方法和蒙特卡洛阈值规则的新消噪方法。该算法充分利用曲波系数的相关性,消除了因Curvelet变换缺乏平移不变性引起的图像"划痕"失真和"振铃"效应。实验结果表明,该算法与传统的小波消噪、二代小波消噪、小波包消噪和曲波硬阈值消噪相比,得到降噪图像的峰值信噪比更高,视觉效果更好。 展开更多
关键词 快速离散曲波变换 图像降噪 wrapping算法 循环平移
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PTN中一种MPLS-TP环共享保护方法 被引量:4
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作者 孙捷 蒋杰 杨岱云 《光通信技术》 CSCD 北大核心 2014年第3期21-23,共3页
介绍了MPLS-TP环保护倒换(MRPS)的工作机制,提出了一种共享保护隧道的MRPS方案,详述了其保护倒换原理,给出了基于此原理的多环互联时的共享保护方法。此外,还针对共享保护环的LSP标签限制,分析了其产生原因,并给出了消除该限制的方案。
关键词 MRPS wrapping 共享保护隧道 LSP
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一种新型的环网保护倒换机制(英文) 被引量:1
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作者 唐世庆 孙以泽 +1 位作者 王琦 黄蕾 《电讯技术》 北大核心 2015年第7期730-735,共6页
环网保护是ITU-T和IETF联合工作组正在研究的多协议标签交换传送应用(MPLS-TP)关键技术之一。在研究现有的环网保护方案的基础上,提出了一种新颖的快速"Wrapping"环网保护倒换机制以及对应的分布式实现方式。运用这种快速的&q... 环网保护是ITU-T和IETF联合工作组正在研究的多协议标签交换传送应用(MPLS-TP)关键技术之一。在研究现有的环网保护方案的基础上,提出了一种新颖的快速"Wrapping"环网保护倒换机制以及对应的分布式实现方式。运用这种快速的"Wrapping"环网保护倒换机制及其对应的分布式实现方式,可以降低在保护倒换中数据的丢失率。同时,分布式实现方式易于增加保护组容量,简化网络管理操作,增强设备可靠性。 展开更多
关键词 MPLS-TP 环网保护 保护倒换 快速“wrapping 分布式实现
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PTN组网的保护技术选择 被引量:8
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作者 郭雄飞 张优训 《移动通信》 2010年第24期32-36,共5页
文章通过对PTN技术的跟踪和研究,重点介绍PTN组网方案中核心环节之一:保护技术选择;结合3G基站回传业务中PTN技术应用的成功经验,分析在城域传输网络中应如何选择PTN网络的保护方式和策略;通过对设备级、网络级各种保护方式的比较分析,... 文章通过对PTN技术的跟踪和研究,重点介绍PTN组网方案中核心环节之一:保护技术选择;结合3G基站回传业务中PTN技术应用的成功经验,分析在城域传输网络中应如何选择PTN网络的保护方式和策略;通过对设备级、网络级各种保护方式的比较分析,探讨各项保护技术优劣;最终给出PTN技术在3G基站回传网络建设中的保护技术选择建议。 展开更多
关键词 PTN 网络保护 LAG保护 wrapping保护 3G基站回传业务
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基于快速曲波变换和独立分量分析的有噪图像盲分离算法 被引量:1
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作者 毕杨 肖军 《自动化技术与应用》 2010年第1期53-56,共4页
曲波(Curvelet)变换有两种数值实现方法,一种是基于非均匀采样的快速Fourier变换即usfft算法;另一种是基于特殊选择的Fourier采样的卷绕即wrapping算法。将这两种实现方法针对图像去噪性能进行了比较,并且提出将曲波变换的wrapping算法... 曲波(Curvelet)变换有两种数值实现方法,一种是基于非均匀采样的快速Fourier变换即usfft算法;另一种是基于特殊选择的Fourier采样的卷绕即wrapping算法。将这两种实现方法针对图像去噪性能进行了比较,并且提出将曲波变换的wrapping算法和FastICA算法结合起来,对含有噪声的混合图像进行了盲分离。仿真研究结果表明,对于含有加性观测噪声的混合图像,该方法有更好的去噪分离效果,并且运算速度显著提高。 展开更多
关键词 快速离散曲波变换 usfft算法 wrapping算法 FASTICA算法 图像盲分离
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一种快速的曲波变换图像去噪算法 被引量:2
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作者 毕杨 《科技信息》 2009年第16期11-12,共2页
第二代Curvelet变换有两种数值实现方法,一种是基于非均匀采样的快速Fourier变换;另一种是基于特殊选择的Fourier采样的卷绕。本文将这两种实现方法进行了比较,并且将其应用到图像去噪中,分析噪声进行curvelet变换后的系数特点,采用曲... 第二代Curvelet变换有两种数值实现方法,一种是基于非均匀采样的快速Fourier变换;另一种是基于特殊选择的Fourier采样的卷绕。本文将这两种实现方法进行了比较,并且将其应用到图像去噪中,分析噪声进行curvelet变换后的系数特点,采用曲波硬阈值去噪。试验结果表明,wrapping曲波变换算法比usfft算法具有更好的去噪效果,并且运算速度显著提高。 展开更多
关键词 快速离散曲波变换 usfft算法 wrapping算法 图像去噪
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基于快速曲波变换的数字水印算法
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作者 毕杨 《科学技术与工程》 2011年第19期4631-4635,共5页
为适应大图像的数字水印,结合快速曲波算法的特点和人类视觉特征,设计了一种快速的数字水印算法。仿真研究结果表明,基于usfft算法和基于wrapping算法的数字水印算法都能较好地保证数字水印的鲁棒性和不可见性之间的统一,并且基于wrapp... 为适应大图像的数字水印,结合快速曲波算法的特点和人类视觉特征,设计了一种快速的数字水印算法。仿真研究结果表明,基于usfft算法和基于wrapping算法的数字水印算法都能较好地保证数字水印的鲁棒性和不可见性之间的统一,并且基于wrapping算法在提高了运行速度方面效果更加显著。 展开更多
关键词 快速离散曲波变换 usfft算法 wrapping算法 数字水印算法
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