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An approach for heritage settlement classification using block patterns:The study of 37 typical colonial heritage settlements in the Americas
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作者 Wei Wei Liyang Liu +1 位作者 Zhaosong Niu Hongrui Li 《Frontiers of Architectural Research》 2025年第4期983-1000,共18页
Settlements serve as the tangible carriers of civilization,with historic urban blocks reflecting distinct cultural attributes that are essential for analyzing settlement types,exploring urban form characteristics,and ... Settlements serve as the tangible carriers of civilization,with historic urban blocks reflecting distinct cultural attributes that are essential for analyzing settlement types,exploring urban form characteristics,and refining spatial planning ideologies.Thus,this study focuses on the block as the fundamental morphological unit and introduces a structured research methodology from the typo-morphological perspective,comprising the following stages:Block Morphology Quantification,Block Pattern Types Extraction,Settlement Type Division,and Planning Ideology Discussion.This methodology can efficiently enhance the understanding of morphology and planning ideologies of heritage settlements by applying quantitative approaches to clustering settlements based solely on block pattern.For method validation,37 typical colonial heritage settlements in the Americas is conducted as empirical study through the following process:first,quantifying block morphology;second,identifying block pattern types by K-means clustering;third,applying hierarchical clustering referring to the proportion of block pattern types within each case,resulting in the identification of four categories of"strategic core","corridor node","resource spot"and"overseas new town";lastly,three key planning ideologies-"order","efficiency"and"practicality"—that shaped these settlements are derived from classification results accordingly.As empirical study result,the effectiveness of classifying heritage settlements using block patterns is validated. 展开更多
关键词 Heritage settlement morphology block pattern Typo-morphology Urban form
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Simulation of Landscape Pattern of Old Growth Forests of Korean Pine By Block Kriging 被引量:1
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作者 王政权 张颜东 +1 位作者 王庆成 HarbinLi 《Journal of Forestry Research》 SCIE CAS CSCD 1997年第3期131-136,共6页
The study area was located in Liangshui Natural Reserve. Xaoxing'an Mountains. Northeastern China. Korean pine forests are the typical forest ecosystems and landscapcs in this region. It is a high degrees of spati... The study area was located in Liangshui Natural Reserve. Xaoxing'an Mountains. Northeastern China. Korean pine forests are the typical forest ecosystems and landscapcs in this region. It is a high degrees of spatial and temporal hetcrogeneity at different scales, which effected on landscape pattern and processes. In this paper we used the data of 144 plots and semivariogram to analyze spatial heterogeneity of old growth forests of Korean pine in landscape level. Model for forest variations by isotropic semivariogram is linear with sill. The spatial heterogeneity is dependent on scales and dircctions in Korean pine forests. Patterns of forest types in space were resulted from complex interactions between physical and biological forces. We uscd 20 metres for interpolation interval to cstimate the values of unsampled area. Comparing the results with field data, block kriging and mapping are an cffective techniques to simulate landscape pattern. 展开更多
关键词 Korean pine SEMIVARIOGRAM block kriging SIMULATION Landscape pattern
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From Self-assembled Monolayers to Chemically Patterned Brushes:Controlling the Orientation of Block Copolymer Domains in Films by Substrate Modification 被引量:3
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作者 Xiao-sa Jin Yuan-yuan Pang 季生象 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2016年第6期659-659,660-678,共20页
Block copolymer lithography is emerging as one of the leading technologies for patteming nanoscale dense features. In almost all potential applications of this technology, control over the orientation of cylindrical a... Block copolymer lithography is emerging as one of the leading technologies for patteming nanoscale dense features. In almost all potential applications of this technology, control over the orientation of cylindrical and lamellar domains is required for pattern transfer from the block copolymer film. This review highlights the state-of-art development of brushes to modify the substrates to control the assembly behaviors of block copolymers in films. Selected important contributions to the development of self-assembled monolayers, polymer brushes and mats, and chemically patterned brushes are discussed. 展开更多
关键词 SELF-ASSEMBLY block copolymer Neutral brush Chemical pattern Wetting behavior.
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On the Blocking Flow Patterns in the Euro–Atlantic Sector:A Simple Model Study
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作者 LUO Dehai YAO Yao 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第5期1181-1196,共16页
The flow patterns of Euro-Atlantic blocking events in winter are investigated by dividing the sector into three sub- regions: 60°-30°W (Greenland region); 20°W-30°E [eastern Atlantic-Europe (EA... The flow patterns of Euro-Atlantic blocking events in winter are investigated by dividing the sector into three sub- regions: 60°-30°W (Greenland region); 20°W-30°E [eastern Atlantic-Europe (EAE) region]; and 50°-90°E (Ural region). It is shown that blocking events in winter are extremely frequent in the three sub-regions. Composite 500-mb geopotential height fields for intense and long-lived blocking events demonstrate that the blocking fields over Greenland and Ural regions exhibit southwest-northeast (SW-NE) and southeast-northwest (SE-NW) oriented dipole-type patterns, respectively, while the composite field over the EAE region exhibits an Ω-type pattern. The type of composite blocking pattern seems to be related to the position of the blocking region relative to the positive center of the climatological stationary wave (CSW) anomaly existing near 10°W. The physical cause of why there are different composite blocking types in the three sub-regions is identified using a nonlinear multiscale interaction model. It is found that when the blocking event is in almost the same position as the positive CSW anomaly, the planetary-scale field can exhibit an Ω-type pattern due to the enhanced positive CSW anomaly. Neverthe- less, a SW-NE (SE-NW) oriented dipole-type block can occur due to the reduced positive CSW anomaly as it is farther in the west (east) of the positive CSW anomaly. The total fields of blocking in the three regions may exhibit a meandering flow comprised of several isolated anticyclonic and cyclonic vortices, which resembles the Berggren-Bolin-Rossby meandering jet type. 展开更多
关键词 blocking flow pattern synoptic eddies nonlinear multiscale interaction climatological stationary wave anomaly
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Does the Luangwa Hippo Population Size and Density Distribution Vary between Upper and Lower Study Blocks? What Are the Management Implications of Such Distribution Pattern? 被引量:2
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作者 Chansa Chomba Twakundine Simpamba +1 位作者 George Kampamba Vincent Nyirenda 《Open Journal of Ecology》 2014年第5期262-280,共19页
The pattern of population distribution of the common hippopotamus was examined along the 165 km stretch of the Luangwa River in eastern Zambia. The study area was divided between the upper (A-D) and lower (E-H) study ... The pattern of population distribution of the common hippopotamus was examined along the 165 km stretch of the Luangwa River in eastern Zambia. The study area was divided between the upper (A-D) and lower (E-H) study blocks. Population data are collected between 1976-2008 and this study 2009-2012 showed a significant difference in the pattern of density distribution between upper and lower study blocks. Upper blocks had higher density of 41/km than lower blocks 29/km. Length of study blocks was discounted as density was used to determine distribution pattern. Results obtained suggest that primary production in each study block as influenced by river geomorphologic features such as river bends and confluences characterized higher hippopotamus density in the upper blocks. Further research is required to investigate other factors that may have interplayed with food (above ground grass biomass) and river meander features to separate upper and lower blocks. 展开更多
关键词 Common HIPPOPOTAMUS pattern Density UPPER blockS LOWER blockS
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Classification of Gastric Lesions Using Gabor Block Local Binary Patterns
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作者 Muhammad Tahir Farhan Riaz +1 位作者 Imran Usman Mohamed Ibrahim Habib 《Computer Systems Science & Engineering》 SCIE EI 2023年第9期4007-4022,共16页
The identification of cancer tissues in Gastroenterology imaging poses novel challenges to the computer vision community in designing generic decision support systems.This generic nature demands the image descriptors ... The identification of cancer tissues in Gastroenterology imaging poses novel challenges to the computer vision community in designing generic decision support systems.This generic nature demands the image descriptors to be invariant to illumination gradients,scaling,homogeneous illumination,and rotation.In this article,we devise a novel feature extraction methodology,which explores the effectiveness of Gabor filters coupled with Block Local Binary Patterns in designing such descriptors.We effectively exploit the illumination invariance properties of Block Local Binary Patterns and the inherent capability of convolutional neural networks to construct novel rotation,scale and illumination invariant features.The invariance characteristics of the proposed Gabor Block Local Binary Patterns(GBLBP)are demonstrated using a publicly available texture dataset.We use the proposed feature extraction methodology to extract texture features from Chromoendoscopy(CH)images for the classification of cancer lesions.The proposed feature set is later used in conjuncture with convolutional neural networks to classify the CH images.The proposed convolutional neural network is a shallow network comprising of fewer parameters in contrast to other state-of-the-art networks exhibiting millions of parameters required for effective training.The obtained results reveal that the proposed GBLBP performs favorably to several other state-of-the-art methods including both hand crafted and convolutional neural networks-based features. 展开更多
关键词 Texture analysis Gabor filters gastroenterology imaging convolutional neural networks block local binary patterns
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Simple Metrics for Representing East Asian Winter Monsoon Variability:Urals Blocking and Western Pacific Teleconnection Patterns 被引量:1
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作者 Hoffman H.N.CHEUNG Wen ZHOU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第6期695-705,共11页
Instead of conventional East Asian winter monsoon indices (EAWMIs), we simply use two large-scale teleconnection patterns to represent long-term variations in the EAWM. First, the Urals blocking pattern index (UBI... Instead of conventional East Asian winter monsoon indices (EAWMIs), we simply use two large-scale teleconnection patterns to represent long-term variations in the EAWM. First, the Urals blocking pattern index (UBI) is closely related to cold air advection from the high latitudes towards western Siberia, such that it shows an implicit linkage with the Siberian high intensity and the surface air temperature (SAT) variations north of 40°N in the EAWM region. Second, the well-known western Pacific teleconnection index (WPI) is connected with the meridional displacement of the East Asian jet stream and the East Asian trough. This is strongly related to the SAT variations in the coastal area south of 40°N in the EAWM region. The temperature variation in the EAWM region is also represented by the two dominant temperature modes, which are called the northern temperature mode (NTM) and the southern temperature mode (STM). Compared to 19 existing EAWMIs and other well-known teleconnection patterns, the UBI shows the strongest correlation with the NTM, while the WPI shows an equally strong correlation with the STM as four EAWMIs. The UBI-NTM and WPI-STM relationships are robust when the correlation analysis is repeated by (1) the 31-year running correlation and (2) the 8-year high-pass and low-pass filter. Hence, these results are useful for analyzing the large-scale teleconnections of the EAWM and for evaluating this issue in climate models. Int particular, more studies should focus on the teleconnection patterns over extratropical Eurasia. 展开更多
关键词 East Asian winter monsoon Urals blocking high western Pacific teleconnection pattern TELECONNECTION
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Beam Pattern Scanning (BPS) versus Space-Time Block Coding (STBC) and Space-Time Trellis Coding (STTC)
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作者 Peh Keong TEH Seyed ZEKAVAT 《International Journal of Communications, Network and System Sciences》 2009年第6期469-479,共11页
In this paper, Beam Pattern Scanning (BPS), a transmit diversity technique, is compared with two well known transmit diversity techniques, space-time block coding (STBC) and space-time trellis coding (STTC). In BPS (a... In this paper, Beam Pattern Scanning (BPS), a transmit diversity technique, is compared with two well known transmit diversity techniques, space-time block coding (STBC) and space-time trellis coding (STTC). In BPS (also called beam pattern oscillation), controlled time varying weight vectors are applied to the antenna array elements mounted at the base station (BS). This creates a small movement in the antenna array pattern directed toward the desired user. In rich scattering environments, this small beam pattern movement creates an artificial fast fading channel. The receiver is designed to exploit time diversity benefits of the fast fading channel. Via the application of simple combining techniques, BPS improves the probability-of-error performance and network capacity with minimal cost and complexity. In this work, to highlight the potential of the BPS, we compare BPS and Space-Time Coding (i.e., STBC and STTC) schemes. The comparisons are in terms of their complexity, system physical dimension, network capacity, probability-of-error performance, and spectrum efficiency. It is shown that BPS leads to higher network capacity and performance with a smaller antenna dimension and complexity with minimal loss in spectrum efficiency. This identifies BPS as a promising scheme for future wireless communications with smart antennas. 展开更多
关键词 Antenna Array Beam pattern SWEEPING Transmit Diversity SPACE-TIME block CODES and SPACE-TIME TRELLIS Coding
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Improvement of the Fit of Bra Prototypes Developed Based on the Existing Bodice Blocks for Adult Women 被引量:1
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作者 刘驰 王利珍 +1 位作者 贾培培 徐步高 《Journal of Donghua University(English Edition)》 EI CAS 2018年第3期244-251,共8页
An in-depth study of bra pattern designs based on the existing bodice blocks was conducted to improve bra fit.The two popular bra prototypes,D's and Y's prototypes developed based on the existing bodice blocks... An in-depth study of bra pattern designs based on the existing bodice blocks was conducted to improve bra fit.The two popular bra prototypes,D's and Y's prototypes developed based on the existing bodice blocks for adult women,were first analyzed to understand their structural differences.Four bra samples were created and modified with respect to the standard shape and size of 75 B female mannequin breasts to compare the fit of the two bra prototypes.The fitness of these four bra samples was then tested on the mannequin and also on a real model of the same size.The examples demonstrated in the paper illustrate the principles and procedures for designing good-fit bras,and the bodice blocks using to develop bra prototypes in this study can also be replaced and widespread applied in other kind of bodice blocks in the future. 展开更多
关键词 bra prototype bodice block pattern design intimate apparel bra fit
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GIS-based analysis of fault patterns in urban areas: A case study of Irkutsk city, Russia 被引量:2
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作者 R.M. Lobatskaya I.P. Strelchenko 《Geoscience Frontiers》 SCIE CAS CSCD 2016年第2期287-294,共8页
The capabilities of GIS in modeling fault patterns are explored for Irkutsk city in East Siberia with implications for ground stability. The neotectonic structure of the area is visualized in three dimension (3D) ta... The capabilities of GIS in modeling fault patterns are explored for Irkutsk city in East Siberia with implications for ground stability. The neotectonic structure of the area is visualized in three dimension (3D) taking into account fault dips, using the ArcGIS, GlobalMapper and Paradigm Geophysical packages. The study area is divided into blocks of different size classes according to the length-based ranks of the bounding faults, which are of five classes distinguished with the equal interval method. The blocks show different deformation patterns, with different densities and strikes of crossing and bounding faults. The data are statistically processed using GIS to estimate the deformation degrees of blocks in arbitrary units per square kilometer using the attributes of rank and crossing/bounding position of faults and the size of blocks. The deformation degrees are then compared with available estimates of ground stability measured as a score of points corresponding to destabilizing factors. Although the comparison generally confirms some linkage between the deformation degree of blocks and their ground stability, the correlation is intricate and ambiguous. In order to enhance the advantages of GIS in building and analyzing 3D models of fault patterns for estimating ground stability and mitigating geological hazards, it is expected in the future to proceed from the reported initial step of visualization to more advanced analysis. 展开更多
关键词 GIS 3D modeling Fault pattern FAULTS blockS Ground stability
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LBlock算法的基于比特积分攻击 被引量:1
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作者 潘志舒 郭建胜 《信息工程大学学报》 2013年第1期30-35,共6页
对分组密码算法LBlock在基于比特积分攻击下的安全性进行了分析,利用基于比特的积分攻击思想,构造了8轮积分区分器,并向前扩展到12轮,基于该区分器对17轮算法进行了积分攻击,给出了攻击算法,攻击的计算复杂度约为263.7。
关键词 分组密码 密码分析 基于比特积分攻击 Lblock算法
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Regional Geochemical Division—A Tool for Delineating Geochemical Block 被引量:3
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作者 Chen Ming Yan Guangsheng Department of Geology, China University of Geosciences, Beijing 100083 Fan Jizhang Li Jingchao Geomathematics Institute, Changchun University of Science and Technology, Changchun 130026 《Journal of Earth Science》 SCIE CAS CSCD 2000年第2期58-61,共4页
Regional geochemical division is a mapping technique to divide an area into slices where the associations between geochemical elements are relatively simple and uniform. The result of division is expressed on a 2 D ma... Regional geochemical division is a mapping technique to divide an area into slices where the associations between geochemical elements are relatively simple and uniform. The result of division is expressed on a 2 D map. The scheme of regional geochemical division includes non supervised pattern recognition, elementary statistics and factor analysis. A practical example in a gold prospecting area in Jilin, China, and the corresponding explanation are presented. Regional geochemical division is a basic approach to the delineation of the geochemical blocks as well. 展开更多
关键词 regional geochemical exploration regional geochemical division C transformation pattern RECOGNITION geochemical block association of elements.
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An efficient BTC image compression algorithm with visual patterns
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作者 陆哲明 潘正祥 孙圣和 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2000年第3期62-65,共4页
Discusses block truncation coding (BTC) a simple and fast image compression technique suitable for real time image transmission with high channel error resisting capability and good reconstructed image quality, and it... Discusses block truncation coding (BTC) a simple and fast image compression technique suitable for real time image transmission with high channel error resisting capability and good reconstructed image quality, and its main drawback of high bit rate of 2 bits/pixel for a 256 gray image for the purpose of reducing the bit rate, and introduces a simple look up table method for coding the higher mean and the lower mean of a block, and a set of 24 visual patterns used to encode 4×4 bit plane of the high detail block and proposes a new algorithm, when needs only 19 bits to encode 4×4 high detail block and 12 bits to encode the 4×4 low detail block. 展开更多
关键词 block TRUNCATION CODING VISUAL patternS image compression
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Finite-Time Normal Mode Disturbances and Error Growth During Southern Hemisphere Blocking
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作者 Jorgen S.FREDERIKSEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第1期69-89,共21页
The structural organization of initially random errors evolving in abarotropic tangent linear model, with time-dependent basic states taken from analyses, is examinedfor cases of block development, maturation and deca... The structural organization of initially random errors evolving in abarotropic tangent linear model, with time-dependent basic states taken from analyses, is examinedfor cases of block development, maturation and decay in the Southern Hemisphere atmosphere duringApril, November, and December 1989. The statistics of 100 evolved errors are studied for six-dayperiods and compared with the growth and structures of fast growing normal modes and finite-timenormal modes (FTNMs). The amplification factors of most initially random errors are slightly lessthan those of the fastest growing FTNM for the same time interval. During their evolution, thestandard deviations of the error fields become concentrated in the regions of rapid dynamicaldevelopment, particularly associated with developing and decaying blocks. We have calculatedprobability distributions and the mean and standard deviations of pattern correlations between eachof the 100 evolved error fields and the five fastest growing FTNMs for the same time interval. Themean of the largest pattern correlation, taken over the five fastest growing FTNMs, increases withincreasing time interval to a value close to 0.6 or larger after six days. FTNM 1 generally, but notalways, gives the largest mean pattern correlation with error fields. Corresponding patterncorrelations with the fast growing normal modes of the instantaneous basic state flow aresignificant' but lower than with FTNMs. Mean pattern correlations with fast growing FTNMs increasefurther when the time interval is increased beyond six days. 展开更多
关键词 normal modes finite-time normal modes blockING tangent linear model pattern correlations
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Steganalysis of MSU Stego Video Based on Block Matching of Interframe Collusion and Motion Detection
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作者 REN Yanzhen WANG Mingjie +2 位作者 ZHAO Yanbin WANG Lina CAI Tingting 《Wuhan University Journal of Natural Sciences》 CAS 2012年第5期441-446,共6页
MSU Stego Video is a public video steganographic tool, which has strong robustness and is regarded as a real video steganographic tool. In order to increase the detection rate, this paper proposes a new steganoalysis ... MSU Stego Video is a public video steganographic tool, which has strong robustness and is regarded as a real video steganographic tool. In order to increase the detection rate, this paper proposes a new steganoalysis method against MSU, which uses the chessboard character of MSU embedded video, proposes a down-sample block-based collusion method to estimate the original frame and checks the chessboard mode of the different frame between tested frame and estimated frame to detect MSU steganographic evidences. To reduce the error introduced by severe movement of the video content, a method that abandons severe motion blocks from detecting is proposed. The experiment results show that the false negative rate of the proposed algorithm is lower than 5%, and the false positive rate is lower than 2%. Our algorithm has significantly better performance than existing algorithms. Especially to the video that has fast motion, the algorithm has more remarkable performance. 展开更多
关键词 MSU Stego Video video steganalysis block-based matching chessboard pattern motion detection
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Fault-Propagate Pattern Based DFA on PRESENT and PRINTcipher 被引量:2
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作者 ZHAO Xinjie GUO Shize +2 位作者 WANG Tao ZHANG Fan SHI Zhijie 《Wuhan University Journal of Natural Sciences》 CAS 2012年第6期485-493,共9页
This article proposes an enhanced differential fault analysis(DFA) method named as fault-propagation pattern-based DFA(FPP-DFA).The main idea of FPP-DFA is using the FPP of the ciphertext difference to predict the... This article proposes an enhanced differential fault analysis(DFA) method named as fault-propagation pattern-based DFA(FPP-DFA).The main idea of FPP-DFA is using the FPP of the ciphertext difference to predict the fault location and the fault-propagation path.It shows that FPP-DFA is very effective on SPN structure block ciphers using bitwise permutation,which is applied to two block ciphers.The first is PRESENT with the substitution permutation sequence.With the fault model of injecting one nibble fault into the r-2nd round,on average 8 and 16 faults can reduce the key search space of PRESENT-80/128 to 214.7 and 221.1,respectively.The second is PRINTcipher with the permutation substitution sequence.For the first time,it shows that although the permutation of PRINTcipher is secret key dependent,FPP-DFA still works well on it.With the fault model of injecting one nibble fault into the r-2nd round,12 and 24 effective faults can reduce the key search space of PRINTcipher-48/96 to 213.7 and 222.8,respectively. 展开更多
关键词 fault-propagation pattern differential fault analysis bitwise permutation SPN block cipher PRESENT PRINTcipher
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高校大胸围青年女性上装原型合体性研究
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作者 曹蓓 姜泽虹 黎佳美 《染整技术》 2025年第1期74-76,共3页
前期通过查阅文献,归纳总结高校女性学生的体型特点,探讨大胸围女性着装合体性的问题,对西安地区100名高校女性学生进行人体测量,并结合胸围身高比指数分析大胸围女性衣身各部位尺寸。以新文化原型制图方法为基础,完成高校大胸围青年女... 前期通过查阅文献,归纳总结高校女性学生的体型特点,探讨大胸围女性着装合体性的问题,对西安地区100名高校女性学生进行人体测量,并结合胸围身高比指数分析大胸围女性衣身各部位尺寸。以新文化原型制图方法为基础,完成高校大胸围青年女性上装原型的制图、板型修改及应用实践。该研究结果能够丰富女性体型的分类,为合体女装的结构设计提供参考。 展开更多
关键词 大胸围体型 上装原型 合体性服装
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二维板材排样问题的递归多块布局算法 被引量:1
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作者 潘卫平 樊治平 +1 位作者 黄敏 计明军 《计算机集成制造系统》 北大核心 2025年第6期2153-2164,共12页
针对矩形件二维板材排样问题,提出递归多块排样方式及其动态规划生成算法。递归多块排样方式将板材划分成多个块,然后递归地对每个块进行多块划分,直到每个新产生的块中排放一种最优矩形件为止。为了均衡考虑排样方式的计算复杂度和板... 针对矩形件二维板材排样问题,提出递归多块排样方式及其动态规划生成算法。递归多块排样方式将板材划分成多个块,然后递归地对每个块进行多块划分,直到每个新产生的块中排放一种最优矩形件为止。为了均衡考虑排样方式的计算复杂度和板材排样价值,对于一刀切排样问题将多块划分的块数定为两块,对于非一刀切排样问题将多块划分的块数定为5块。动态规划算法首先计算每个块中分别排放一种矩形件所得到的1阶多块排样方式的最大价值,然后计算每个块中分别排放一个1阶多块排样方式得到的2阶多块排样方式的最大价值,以此递推,得到任意阶数的多块排样方式的最大价值。通过比较块的排样价值的上界和下界来剔除不必要的多块划分,通过离散化划分线位置来控制算法的时间复杂度。采用文献典型例题和实际生产实例,将所提算法与一刀切排样算法和非一刀切排样算法进行对比,表明了所提算法的优越性。 展开更多
关键词 二维板材排样 递归多块排样方式 动态规划 排样价值 矩形件
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推力墩对电站枢纽混凝土拱坝应力变形的影响分析
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作者 李强 郝泽阳 李庆铁 《水科学与工程技术》 2025年第6期55-57,共3页
以波黑优乐高电站枢纽为例,为解决左右岸现有地质条件不对称问题,需在左岸设置一个推力墩,使两岸坝肩岩体质量趋于一致。通过建立包含拱坝、地基和推力墩在内的整体三维模型,模拟不同推力墩高度搭配温升和温降的不同工况,验证结果表明... 以波黑优乐高电站枢纽为例,为解决左右岸现有地质条件不对称问题,需在左岸设置一个推力墩,使两岸坝肩岩体质量趋于一致。通过建立包含拱坝、地基和推力墩在内的整体三维模型,模拟不同推力墩高度搭配温升和温降的不同工况,验证结果表明设置推力墩可较好地改善优乐高拱坝和坝肩的应力变形条件,研究结果可为类似工程建设提供参考。 展开更多
关键词 拱坝 推力墩 应力变形
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图形设计对铜柱电镀单元均匀性的影响
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作者 秦华 陈先明 +5 位作者 黄本霞 黄贵 罗阳 晏小磊 李志丹 邓小峰 《电镀与涂饰》 北大核心 2025年第12期7-13,共7页
[目的]针对高散热性能基板(PHS)中导通铜柱与散热铜块因图形差异导致的电镀厚度不均匀问题,研究图形设计对电镀单元均匀性的影响,以实现对铜柱厚度的精准控制。[方法]通过正交试验,研究了图形中散热铜块尺寸、散热铜块与导通铜柱的间距... [目的]针对高散热性能基板(PHS)中导通铜柱与散热铜块因图形差异导致的电镀厚度不均匀问题,研究图形设计对电镀单元均匀性的影响,以实现对铜柱厚度的精准控制。[方法]通过正交试验,研究了图形中散热铜块尺寸、散热铜块与导通铜柱的间距及导通铜柱的干膜厚度与开窗直径之比(即图形纵横比)对铜柱电镀单元均匀性(以散热铜块与导通铜柱高度差表示)的影响,并基于多元线性回归建立预测模型。[结果]导通铜柱的图形纵横比对电镀单元均匀性影响最大,纵横比越大,电镀单元均匀性越差;其次为铜块与铜柱的间距,越小则电镀单元均匀性越差;散热铜块尺寸对电镀单元均匀性影响不显著。基于关键因素建立的预测模型拟合优度良好,具备较高的预测准确性。[结论]本研究明确了图形设计中影响铜柱电镀均匀性的关键因素及其影响规律,所建立的模型可用于预测不同图形设计下的电镀均匀性,为实际生产中的图形优化与工艺参数设定提供有效指导,有助于提升产品良率并降低生产成本。 展开更多
关键词 铜柱 铜块 图形设计 电镀 厚度均匀性
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