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Improving Video Watermarking through Galois Field GF(2^(4)) Multiplication Tables with Diverse Irreducible Polynomials and Adaptive Techniques
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作者 Yasmin Alaa Hassan Abdul Monem S.Rahma 《Computers, Materials & Continua》 SCIE EI 2024年第1期1423-1442,共20页
Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content authenticity.This study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4))... Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content authenticity.This study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4)),and their interaction with distinct irreducible polynomials.The primary aim is to enhance watermarking techniques for achieving imperceptibility,robustness,and efficient execution time.The research employs scene selection and adaptive thresholding techniques to streamline the watermarking process.Scene selection is used strategically to embed watermarks in the most vital frames of the video,while adaptive thresholding methods ensure that the watermarking process adheres to imperceptibility criteria,maintaining the video's visual quality.Concurrently,careful consideration is given to execution time,crucial in real-world scenarios,to balance efficiency and efficacy.The Peak Signal-to-Noise Ratio(PSNR)serves as a pivotal metric to gauge the watermark's imperceptibility and video quality.The study explores various irreducible polynomials,navigating the trade-offs between computational efficiency and watermark imperceptibility.In parallel,the study pays careful attention to the execution time,a paramount consideration in real-world scenarios,to strike a balance between efficiency and efficacy.This comprehensive analysis provides valuable insights into the interplay of GF multiplication tables,diverse irreducible polynomials,scene selection,adaptive thresholding,imperceptibility,and execution time.The evaluation of the proposed algorithm's robustness was conducted using PSNR and NC metrics,and it was subjected to assessment under the impact of five distinct attack scenarios.These findings contribute to the development of watermarking strategies that balance imperceptibility,robustness,and processing efficiency,enhancing the field's practicality and effectiveness. 展开更多
关键词 Video watermarking galois field irreducible polynomial multiplication table scene selection adaptive thresholding
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A novel control strategy for reproducing the floor motions of high-rise buildings by earthquake-simulating shake tables
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作者 Yuteng Cao Zhe Qu Xiaodong Ji 《Earthquake Research Advances》 CSCD 2024年第1期67-75,共9页
To enable the experimental assessment of the seismic performance of full-scale nonstructural elements with multiple engineering parameters(EDPs),a three-layer testbed named Nonstructural Element Simulator on Shake Tab... To enable the experimental assessment of the seismic performance of full-scale nonstructural elements with multiple engineering parameters(EDPs),a three-layer testbed named Nonstructural Element Simulator on Shake Table(NEST)has been developed.The testbed consists of three consecutive floors of steel structure.The bottom two floors provide a space to accommodate a full-scale room.To fully explore the flexibility of NEST,we propose a novel control strategy to generate the required shake table input time histories for the testbed to track the target floor motions of the buildings of interest with high accuracy.The control strategy contains two parts:an inverse dynamic compensation via simulation of feedback control systems(IDCS)algorithm and an offline iteration procedure based on a refined nonlinear numerical model of the testbed.The key aspects of the control strategy were introduced in this paper.Experimental tests were conducted to simulate the seismic responses of a full-scale office room on the 21^(st)floor of a 42-story high-rise building.The test results show that the proposed control strategy can reproduce the target floor motions of the building of interest with less than 20%errors within the specified frequency range. 展开更多
关键词 Shake table test Nonstructural element High-rise building Open-loop IDCS algorithm Off-line iteration
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Seismic performance evaluation of water supply pipes installed in a full-scale RC frame structure based on a shaking table test 被引量:1
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作者 Wu Houli Guo Endong +2 位作者 Wang Jingyi Dai Xin Dai Chenxi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期163-178,共16页
As an important part of nonstructural components,the seismic response of indoor water supply pipes deserves much attention.This paper presents shaking table test research on water supply pipes installed in a full-scal... As an important part of nonstructural components,the seismic response of indoor water supply pipes deserves much attention.This paper presents shaking table test research on water supply pipes installed in a full-scale reinforced concrete(RC)frame structure.Different material pipes and different methods for penetrating the reinforced concrete floors are combined to evaluate the difference in seismic performance.Floor response spectra and pipe acceleration amplification factors based on test data are discussed and compared with code provisions.A seismic fragility study of displacement demand is conducted based on numerical simulation.The acceleration response and displacement response of different combinations are compared.The results show that the combination of different pipe materials and different passing-through methods can cause obvious differences in the seismic response of indoor riser pipes. 展开更多
关键词 water supply pipe different materials shaking table test amplification factor seismic fragility
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Prevalence of Enteric Pathogens Associated with Infections among Table Egg Consumers in Some Primary Health Establishments in the Center Region of Cameroon
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作者 Mariane Lucie Ngueguim Bernard Viban Tangwa +2 位作者 Victor Ngu Ngwa Albert Ngakou Abdoulmoumini Mamoudou 《Advances in Infectious Diseases》 CAS 2024年第3期606-619,共14页
Method: In Cameroon limited data are available regarding the prevalence of enteric bacteria associated with table egg consuming infections. As such, a situational-based study was performed in patients with complains o... Method: In Cameroon limited data are available regarding the prevalence of enteric bacteria associated with table egg consuming infections. As such, a situational-based study was performed in patients with complains of stomach disorders after egg consumption. Data related to sociodemographic characteristics and other factors were collected using a structured based questionnaire. Stool culture of utmost importance in stomach disorders patients and serum were collected for typhoid serological test. Results: A total of 207 participants took part in the survey, Results indicated nontyphoidal Salmonella infections were highest in the 3 areas of study with Mfoundi (73.44%) having the highest level of infection compared to other bacterial infection. other enteric bacteria associated to this infection were E. coli serotype 157, Aeromonas, Citrobacter freundii, Enterobacter cloaca and typhi salmonella. Meanwhile salmonelosis caused by typhic salmonella had highest prevalence in the Lekie Division (13.11%) as a result of poor hygienic practices associated with the conservation and preparation of eggs, Stool culture was observed to detect more positive cases in the diagnosis of typhoid fever than Widal test, but with no statistically significant (p > 0.05) difference between the stool culture and Widal test in the 3 areas of study. Conclusion: this study revealed that egg consumers are pruned to enteric bacterial and salmonella infections depending on how and where egg is consumed. 展开更多
关键词 Enteric Pathogens table Eggs Consumption Center Region Cameroon
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Accelerated generation of holograms with ultra-low memory symmetrically high-compressed look-up table
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作者 杨燕 朱建英 +1 位作者 孙敏远 毕勇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期466-471,共6页
Computer-generated holography technology has been widely applied,and as research in this field deepens,the demand for memory and computational power in small AR and VR devices continues to increase.This paper presents... Computer-generated holography technology has been widely applied,and as research in this field deepens,the demand for memory and computational power in small AR and VR devices continues to increase.This paper presents a hologram generation method,i.e.,a symmetrically high-compressed look-up table method,which can reduce memory usage by50%.In offline computing,half of the basic horizontal and vertical modulation factors are stored,halving the memory requirements without affecting inline speed.Currently,its potential extends to various holographic applications,including the production of optical diffraction elements. 展开更多
关键词 computergenerated hologram look-up table HOLOGRAPHY
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The Periodic Table of Primes
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作者 Han-Lin Li Shu-Cherng Fang Way Kuo 《Advances in Pure Mathematics》 2024年第5期394-419,共26页
Over millennia, nobody has been able to predict where prime numbers sprout or how they spread. This study establishes the Periodic Table of Primes (PTP) using four prime numbers 2, 3, 5, and 7. We identify 48 integers... Over millennia, nobody has been able to predict where prime numbers sprout or how they spread. This study establishes the Periodic Table of Primes (PTP) using four prime numbers 2, 3, 5, and 7. We identify 48 integers out of a period 2×3×5×7=210 to be the roots of all primes as well as composites without factors of 2, 3, 5, and 7. Each prime, twin primes, or composite without factors of 2, 3, 5, and 7 is an offspring of the 48 integers uniquely allocated on the PTP. Three major establishments made in the article are the Formula of Primes, the Periodic Table of Primes, and the Counting Functions of Primes and Twin Primes. 展开更多
关键词 PRIMES COMPOSITES the Periodic table of Primes
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Opinions of Students on the Contribution of the DIVA 3D Virtual Dissection Table to the Teaching of Anatomy at the Faculty of Medicine and Odontostomatology of Bamako
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作者 Abdoulaye Kanté Tata Touré +8 位作者 Ousmane Toumany Chérif Haidara Uhl Jean François Mariam Daou Mamadou A. Keita Bakary Keïta Bréhima Bengaly Drissa Traoré Adégné Togo Nouhoum Ongoïba 《Forensic Medicine and Anatomy Research》 2024年第2期13-25,共13页
Objective: Study the contribution of the DIVA 3D dissection table in the teaching of anatomy at the Faculty of Medicine and Odontology of Bamako. Material and Methods: This was a qualitative study carried out from Nov... Objective: Study the contribution of the DIVA 3D dissection table in the teaching of anatomy at the Faculty of Medicine and Odontology of Bamako. Material and Methods: This was a qualitative study carried out from November 1 to December 30, 2023 at the clinical and morphological anatomy laboratory of the Faculty of Medicine and Odontostomatology of Bamako. Included in this study were students who participated in practical and tutorial sessions. The variables studied during this study were: the previous performance of dissection on a cadaver by the students, the opinion of the students on dissection on a cadaver, the replacement of dissection on a cadaver by virtual dissection in the absence of a body, the level student satisfaction. Results: We surveyed 130 participants. The average age was 22 ± 0.2 years with extremes of 17 and 29 years. 95.3% of participants were students. According to 66.7% of participants, virtual dissection is a good palliative in the absence of a corpse. 95.3% of participants found using the virtual dissection table easy with an average of 7.88 ± 1.4. The overall assessment was well rated by 99.3% of participants. Conclusion: According to the results of this study, the virtual dissection table should be improved by integrating commented videos. The use of the DIVA 3D virtual dissection table during practical and tutorial sessions is well appreciated by the students. We believe that the teaching of anatomy using 3D digital technology should be included in the study programs of the Faculty of Medicine and Odontostomatology. 展开更多
关键词 Student Opinion CONTRIBUTION DIVA 3D Virtual Dissection table Anatomy Teaching FMOS
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Evaluation of the effects of EPS composite soil replacement on the dynamic performance of caisson structure using shaking table tests
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作者 Gao Hongmei Ji Zhanpeng +3 位作者 Zhang Xinlei Zhang Shushan Wang Zhihua Shen Guangming 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第4期829-843,共15页
The seismic performance of a caisson structure under two types of models with a saturated sandy foundation(CSS)and an expanded polystyrene(EPS)composite soil foundation(CES)are studied using shaking table tests.The ma... The seismic performance of a caisson structure under two types of models with a saturated sandy foundation(CSS)and an expanded polystyrene(EPS)composite soil foundation(CES)are studied using shaking table tests.The macro phenomena of the two different foundation models are described and analyzed.The effects of the replacement of EPS composite soil on seismic-induced liquefaction of backfill and the dynamic performance of a caisson structure are evaluated in detail.The results show that the excess pore water pressure generation in the CES is significantly slower than that in the CSS during the shaking.The dynamic earth pressure acting on the caisson has a triangular shape.The response of horizontal acceleration,displacement,settlement,and rotation angle of the caisson in the CES is smaller than that in the CSS,which means the caisson in the CES has a better seismic performance.Furthermore,the out-of-phase phenomenon between dynamic earth thrust and inertial force in the CES is more obvious than that in the CSS,which is beneficial to reduce the lateral force and improve the stability of the caisson structure. 展开更多
关键词 EPS composite soil foundation Caisson-type quay wall shaking table test phase difference rotation angle
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Numerical analysis on seismic performance of underground structures in liquefiable interlayer sites from centrifuge shaking table test
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作者 Yan Guanyu Xu Chengshun +2 位作者 Zhang Zihong Du Xiuli Wang Xuelai 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第4期781-798,共18页
When an underground structure passes through a liquefiable soil layer,the soil liquefaction may pose a significant threat to the structure.A centrifuge shaking table test was performed to research the seismic response... When an underground structure passes through a liquefiable soil layer,the soil liquefaction may pose a significant threat to the structure.A centrifuge shaking table test was performed to research the seismic response of underground structures in liquefiable interlayer sites,and a valid numerical model was obtained through simulation model test.Finally,the calibrated numerical model was used to perform further research on the influence of various distribution characteristics of liquefiable interlayers on the seismic reaction of underground structures.The key findings are as follows.The structure faces the most unfavorable condition once a liquefiable layer is located in the middle of the underground structure.When a liquefiable layer exists in the middle of the structure,the seismic reactions of both the underground structure and model site will increase with the rise of the thickness of the liquefiable interlayer.The inter-story drift of the structure in the non-liquefiable site is much smaller than that in the liquefiable interlayer site.The inter-story drift of the structure is not only associated with the site displacement and the soil-structure stiffness ratio but also closely associated with the slippage of the soil-structure contact interface under the condition of large deformation of the site. 展开更多
关键词 centrifuge shaking table test underground structure liquefiable interlayer sites seismic response validation of numerical model
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Pre-training transformer with dual-branch context content module for table detection in document images
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作者 Yongzhi LI Pengle ZHANG +2 位作者 Meng SUN Jin HUANG Ruhan HE 《虚拟现实与智能硬件(中英文)》 EI 2024年第5期408-420,共13页
Background Document images such as statistical reports and scientific journals are widely used in information technology.Accurate detection of table areas in document images is an essential prerequisite for tasks such... Background Document images such as statistical reports and scientific journals are widely used in information technology.Accurate detection of table areas in document images is an essential prerequisite for tasks such as information extraction.However,because of the diversity in the shapes and sizes of tables,existing table detection methods adapted from general object detection algorithms,have not yet achieved satisfactory results.Incorrect detection results might lead to the loss of critical information.Methods Therefore,we propose a novel end-to-end trainable deep network combined with a self-supervised pretraining transformer for feature extraction to minimize incorrect detections.To better deal with table areas of different shapes and sizes,we added a dualbranch context content attention module(DCCAM)to high-dimensional features to extract context content information,thereby enhancing the network's ability to learn shape features.For feature fusion at different scales,we replaced the original 3×3 convolution with a multilayer residual module,which contains enhanced gradient flow information to improve the feature representation and extraction capability.Results We evaluated our method on public document datasets and compared it with previous methods,which achieved state-of-the-art results in terms of evaluation metrics such as recall and F1-score.https://github.com/Yong Z-Lee/TD-DCCAM. 展开更多
关键词 table detection Document image analysis TRANSFORMER Dilated convolution Deformable convolution Feature fusion
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Impact of water table on hierarchically nested groundwater flow system
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作者 Jun Zhang Rong-zhe Hou +2 位作者 Kun Yu Jia-qiu Dong Li-he Yin 《Journal of Groundwater Science and Engineering》 2024年第2期119-131,共13页
Water table configuration gives rise to hierarchically nested groundwater flow systems.However,there remains a lack of comprehensive understanding regarding the controlling factors of water table and its impact on flo... Water table configuration gives rise to hierarchically nested groundwater flow systems.However,there remains a lack of comprehensive understanding regarding the controlling factors of water table and its impact on flow systems.Moreover,it remains challenging to identify characteristics of water table space variation through limited groundwater observations at the regional scale.Based on two ideal two-dimensional cross-section analytical models,this study presents a simplified approach to preliminarily assess the nonlinear interactions between water table variation and three driving factors:Topography,geol-ogy and climate.Two criteria,C1 and C2,are utilized to address issues at different scales ranging from basin to local:(i)the influence of various factors on water table configuration;and(ii)the influence of water table on groundwater flow pattern.Then,the Ordos Plateau is taken as an example to explore the role of the water table in nested groundwater systems using the provided approach and criterion.The applica-tion of this approach in the Ordos Plateau demonstrates its appropriateness as a practical method for prelim-inarily determining the characteristics of water table configuration and its impact on flow systems.The study explores the mechanism influencing spatial variation in the water table and improves understanding of the interaction between topography,geology,and climate on groundwater flow patterns. 展开更多
关键词 Water table configuration Groundwater flow pattern Analytical models Top boundary condi-tions Ordos Plateau
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1997版与2007版Partin tables预测国人前列腺癌病理分期准确性的比较 被引量:2
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作者 朱虹 章青 +1 位作者 吴登龙 傅深 《中国肿瘤临床》 CAS CSCD 北大核心 2008年第17期975-979,共5页
目的:验证2007版Partin tables对国人前列腺癌患者病理特征预测的准确性,并与1997版进行比较。方法:选本院2003年1月至2007年9月间,116例前列腺癌患者经根治术后病理确诊为前列腺腺癌,术前资料具备前列摘要目的:验证2007版Partin table... 目的:验证2007版Partin tables对国人前列腺癌患者病理特征预测的准确性,并与1997版进行比较。方法:选本院2003年1月至2007年9月间,116例前列腺癌患者经根治术后病理确诊为前列腺腺癌,术前资料具备前列摘要目的:验证2007版Partin tables对国人前列腺癌患者病理特征预测的准确性,并与1997版进行比较。方腺特异抗原(prostate specific antigen,PSA),临床分期,穿刺活检Gleason评分。根据术后病理分为四型:器官局限(OC),包膜外侵犯(EPE),精囊侵犯(SVI)与淋巴结转移(LNI)。患者中93例符合2007版Partin tables预测入选标准,113例符合1997版预测入选标准,每例患者中分别应用两版Partintables预测术后病理特征的可能性,并通过工作特征曲线(ROC曲线)分析法研究两版Partintables的预测准确性并行比较。结果:根据2007版或1997版Partin tables预测入选标准,本组患者OC、EPE、SVI、LNI发生率分别为51%、15%、13%、22%或50%、16%、12%、23%。应用2007版Partin tables预测OC、EPE、SVI、LNI的ROC曲线下面积(AUC)分别为0.786、0.613、0.666和0.811,而应用1997版预测时分别为0.834、0.605、0.716、0.808。结论:两版Partin tables皆对OC及LNI有合理的预测价值(AUC>0.7),1997版Partin table比2007版显示出更佳的预侧准确性。 展开更多
关键词 前列腺肿瘤 Partin tables 病理分期 试验预测值
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Life Tables for the Experimental Population Phenacoccus solenopsis Tinsley at Different Temperatures 被引量:3
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作者 关鑫 陆永跃 +1 位作者 曾玲 杨玉枝 《Agricultural Science & Technology》 CAS 2012年第4期792-797,814,共7页
[Objective] The study was to investigate the effect of temperature on pop- ulation dynamics of Phenacoccus solenopsis Tinsley, so as to providing references for the control and prevention of this pest. [Method] The ex... [Objective] The study was to investigate the effect of temperature on pop- ulation dynamics of Phenacoccus solenopsis Tinsley, so as to providing references for the control and prevention of this pest. [Method] The experimental populations were kept in laboratory and fed on cotton plants, and the major parameters of the population were recorded. [Result] By the construction of age specific life tables and reproductive life tables for the P. solenopsis experimental population at 24, 27, 30 ~C, more than 10 parameters were obtained, including mean generation time, survival rates of different stages and sexes, life expectancy, spawning period, fecundity amount per female, sexual ratio, net reproductive rate, intrinsic increase rate, finite increase rate, population trend index, curve of survival rate, and curve of daily fe- male oviposition, which revealed the effect of temperature on growth and develop- ment, life expectancy and fecundities of P. solenopsis. [Conclusion] The reproductive potential of the P. solenopsis population is very great at suitable temperature, making it easy to outbreak. The research provided scientific basis for population dynam- ics investigation, predication and integrated control of P. solenopsis. 展开更多
关键词 Phenacoccus solenopsis Tinsley TEMPERATURE Age specific life table Reproductive life table
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Partin tables与Roach公式预测国人前列腺癌病理分期准确性的比较
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作者 朱虹 章青 +1 位作者 吴登龙 傅深 《肿瘤学杂志》 CAS 2008年第7期550-554,共5页
[目的]比较1997版、2007版Partin tables及Roach公式三种方式对国人前列腺癌患者病理特征预测的准确性。[方法]对116例患者应用1997版和2007版的Partin tables查出并利用Roach公式计算出术后病理分期,并通过工作特征曲线(ROC曲线)分析... [目的]比较1997版、2007版Partin tables及Roach公式三种方式对国人前列腺癌患者病理特征预测的准确性。[方法]对116例患者应用1997版和2007版的Partin tables查出并利用Roach公式计算出术后病理分期,并通过工作特征曲线(ROC曲线)分析法比较三种方式预测病理分期的准确性。[结果]应用1997版Partin tables预测器官局限,包膜外侵犯,精囊侵犯或淋巴结转移的ROC曲线下面积(AUC)分别为0.834、0.605、0.716、0.808,而2007版分别为0.786、0.613、0.666和0.811;Roach公式预测包膜外侵犯,精囊侵犯或淋巴结转移的AUC分别为0.495、0.712、0.754。[结论]3种预测方式综合比较,1997版Partin tables对前列腺癌病理特征预测的准确性最佳。 展开更多
关键词 前列腺肿瘤 Partin tables 病理分期
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Netfilter/iptables的架构及应用 被引量:1
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作者 肖媛娥 吕亚南 康永平 《井冈山大学学报(自然科学版)》 2007年第4期37-39,共3页
本文通过研究Linux 2.4/2.6内核netfilter/iptables的架构,介绍了如何利用基于Linux的iptables来构建防火墙。
关键词 NETFILTER/IPtables 表链 规则 防火墙
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IPv6防火墙ip6tables过滤规则配置的图形界面设计
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作者 李晓峰 张玉清 李星 《计算机工程与应用》 CSCD 北大核心 2002年第23期116-117,140,共3页
IPv6的逐渐流行,将带来头痛的IPv6网络安全问题。Linux2.4内核中自带了IPv6防火墙软件———ip6tables,它以命令行的规则配置方式提供了齐全的IPv6过滤功能。但ip6tables的命令行方式,对用户来说使用非常不便,同时使得过滤规则的扩充和... IPv6的逐渐流行,将带来头痛的IPv6网络安全问题。Linux2.4内核中自带了IPv6防火墙软件———ip6tables,它以命令行的规则配置方式提供了齐全的IPv6过滤功能。但ip6tables的命令行方式,对用户来说使用非常不便,同时使得过滤规则的扩充和修改也极为繁琐。为了更为有效地配置IPv6防火墙过滤规则,笔者针对ip6tables设计了一个用过滤规则配置的图形界面,从而可以方便快捷地应用功能强大的ip6tables。 展开更多
关键词 IPV6协议 防火墙 ip6tables 过滤规则 图形界面 设计 网络安全 计算机网络 防火墙软件包
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基于Linux的Netfilter/Iptables技术及其应用 被引量:2
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作者 卢朝晖 傅光轩 《海南师范学院学报(自然科学版)》 2003年第1期35-38,共4页
Netfilter/Iptables是一个集成在Linux内核中的IP数据包过滤系统.文章主要介绍了该 系统的两个基本组件及其基本工作原理,最后应用iptables工具建立一个简单的包过滤防火墙.
关键词 NETFILTER/IPtables IP数据 包过滤系统 LINUX操作系统 包过滤防火墙 网络安全
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COM开发中不同语言Sparse V-Tables接口问题的研究
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作者 李娜 《航空计算技术》 2006年第2期60-62,共3页
基于从事COM相关开发和研究的实际经验,本文对于M icrosoft公司和Borland公司对于Sparse V-Tab les的处理方式进行了研究和实验,并提出了解决此类意外AV问题的方法。
关键词 COM SPARSE V-tables接口 AV问题
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On-line Popularity Monitoring Method Based on Bloom Filters and Hash tables for Differentiated Traffic 被引量:4
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作者 ZHANG Guo ZHANG Jianhui +1 位作者 WANG Binqiang ZHANG Zhen 《China Communications》 SCIE CSCD 2016年第S1期72-86,共15页
Towards line speed and accurateness on-line content popularity monitoring on Content Centric Networking(CCN) routers, we propose a three-stage scheme based on Bloom filters and hash tables for differentiated traffic. ... Towards line speed and accurateness on-line content popularity monitoring on Content Centric Networking(CCN) routers, we propose a three-stage scheme based on Bloom filters and hash tables for differentiated traffic. At the first stage, we decide whether to deliver the content to the next stage depending on traffic types. The second stage consisting of Standard Bloom filters(SBF) and Counting Bloom filters(CBF) identifies the popular content. Meanwhile, a scalable sliding time window based monitoring scheme for different traffic types is proposed to implement frequent and real-time updates by the change of popularities. Hash tables according with sliding window are used to record the popularity at the third stage. Simulation results reveal that this method reaches a 40 Gbps processing speed at lower error probability with less memory, and it is more sensitive to the change of popularity. Additionally, the architecture which can be implemented in CCN router is flexible and scalable. 展开更多
关键词 CCN line speed TRAFFIC type BLOOM filters HASH tables POPULARITY monitoring
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Exploring Soil Layers and Water Tables with Ground-Penetrating Radar 被引量:12
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作者 K.ROTH U.WOLLSCHLAGER +1 位作者 CHENGZhu-Hua ZHANGJia-Bao 《Pedosphere》 SCIE CAS CSCD 2004年第3期273-282,共10页
Ground-penetrating radar (GPR) has been used predominantly for environments with low electrical conductivity like freshwater aquifers, glaciers, or dry sandy soils. The objective of the present study was to explore it... Ground-penetrating radar (GPR) has been used predominantly for environments with low electrical conductivity like freshwater aquifers, glaciers, or dry sandy soils. The objective of the present study was to explore its application for mapping in subsurface agricultural soils to a depth of several meters. For a loamy sand and a clayey site on the North China Plain, clay inclusions in the sand were detected; the thickness, inclination, and continuity of the confining clay and silt layers was assessed; and a local water table was mapped. Direct sampling (soil coring and profiling) in the top meter and independent measurement of the water table were utilized to confirm the findings. Also, effective estimates of the dielectric number for the site with the dielectric number of moist clayey soils depending strongly on frequency were obtained. Thus, important properties of soils, like the arrangement and type of layers and in particular their continuity and inclination, could be explored with moderate efforts for rather large areas to help find optimal locations for the time-consuming and expensive measurements which would be necessary to detail a model of the subsurface. 展开更多
关键词 ground-penetrating radar soil layers water table
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