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Satellite Multi-Temporal Data and Cropping Pattern Approach for Green Gram Crop Management in the Lower Midland Zone IV and V in Kenya
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作者 Kalekye Hilda Manzi Shadrack Ngene Joseph P. Gweyi-Onyango 《Advances in Remote Sensing》 2024年第2期41-71,共31页
Creation of a spectral signature reflectance data, which aids in the identification of the crops is important in determining size and location crop fields. Therefore, we developed a spectral signature reflectance for ... Creation of a spectral signature reflectance data, which aids in the identification of the crops is important in determining size and location crop fields. Therefore, we developed a spectral signature reflectance for the vegetative stage of the green gram (Vigna. radiata L.) over 5 years (2020, 2018, 2017, 2015, and 2013) for agroecological zone IV and V in Kenya. The years chosen were those whose satellite resolution data was available for the vegetative stage of crop growth in the short rain season (October, November, December (OND)). We used Landsat 8 OLI satellite imagery in this study. Cropping pattern data for the study area were evaluated by calculating the Top of Atmosphere reflectance. Farms geo-referencing, along with field data collection, was undertaken to extract Top of Atmosphere reflectance for bands 2, 3, 4 and 7. We also carried a spectral similarity assessment on the various cropping patterns. The spectral reflectance ranged from 0.07696 - 0.09632, 0.07466 - 0.09467, 0.0704047 - 0.12188,0.19822 - 0.24387, 0.19269 - 0.26900, and 0.11354 - 0.20815 for bands 2, 3, 4, 5, 6, and 7 for green gram, respectively. The results showed a dissimilarity among the various cropping patterns. The lowest dissimilarity index was 0.027 for the maize (Zea mays L.) bean (Phaseolus vulgaris) versus the maize-pigeon pea (Cajanus cajan) crop, while the highest dissimilarity index was 0.443 for the maize bean versus the maize bean and cowpea cropping patterns. High crop dissimilarities experienced across the cropping pattern through these spectral reflectance values confirm that the green gram was potentially identifiable. The results can be used in crop type identification in agroecological lower midland zone IV and V for mung bean management. This study therefore suggests that use of reflectance data in remote sensing of agricultural ecosystems would aid in planning, management, and crop allocation to different ecozones. 展开更多
关键词 multi-TEMPORAL Cropping Patterns Spectral signatures Landsat 8 CROP Identification
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A New ID-Based Proxy Multi-Signature Scheme from Bilinear Pairings 被引量:1
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作者 GU Chun-xiang PAN Heng ZHU Yue-fei 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期193-197,共5页
ID-based public key cryptosystem can be a good alternative for certifieate-based public key setting. This paper provides an efficient ID-based proxy multi signature scheme from pairings. In the random oracle model, we... ID-based public key cryptosystem can be a good alternative for certifieate-based public key setting. This paper provides an efficient ID-based proxy multi signature scheme from pairings. In the random oracle model, we prove that our new scheme is secure against existential delegation forgery with the assumption that Hess's scheme-1 is existential unforgeable, and that our new scheme is secure against existential proxy multi-signature forgery under the hardness assumption of the computational Diffie-Hellman problem. 展开更多
关键词 ID-based signatures proxy multi-signature ID-based proxy multi signatures bilinear pairlngs provable security
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Digital Multi-Signature Based on the Controlled Quantum Teleportation 被引量:8
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作者 WEN Xiaojun LIU Yun ZHANG Pengyun 《Wuhan University Journal of Natural Sciences》 CAS 2007年第1期29-32,共4页
In this paper, a scheme which can be used in multi-user quantum digital signature is proposed. The scheme of signature and verification is based on the characters of GHZ (Greenberger-Horne-Zeilinger) states and cont... In this paper, a scheme which can be used in multi-user quantum digital signature is proposed. The scheme of signature and verification is based on the characters of GHZ (Greenberger-Horne-Zeilinger) states and controlled quantum teleportation. Different from the digital signatures based on computational complexity, this scheme is unconditional secure, and compared to the former presented quantum signature scheme, it does not rely on an arbitrator to verify the signature and realize a message can be signed by multi-user together. 展开更多
关键词 quantum digital signature quantum teleportation multi-USER
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Multi-proxy quantum group signature scheme with threshold shared verification 被引量:4
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作者 杨宇光 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期415-418,共4页
A multi-proxy quantum group signature scheme with threshold shared verification is proposed. An original signer may authorize a proxy group as his proxy agent. Then only the cooperation of all the signers in the proxy... A multi-proxy quantum group signature scheme with threshold shared verification is proposed. An original signer may authorize a proxy group as his proxy agent. Then only the cooperation of all the signers in the proxy group can generate the proxy signature on behalf of the original signer. In the scheme, any t or more of n receivers can verify the message and any t - 1 or fewer receivers cannot verify the validity of the proxy signature. 展开更多
关键词 quantum signature multi-proxy quantum group signature threshold shared verification
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A Nominative Multi-Proxy Signature Scheme Based on ECC 被引量:1
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作者 MAChuan-gui GAOFeng-xiu WANGYan 《Wuhan University Journal of Natural Sciences》 CAS 2005年第1期223-226,共4页
A nominative multi-proxy signature in which the original signer authorizes a group of proxy signers is presented. Meanwhile, our proposed scheme is based on elliptic curve cryptosystem which is more efficient than the... A nominative multi-proxy signature in which the original signer authorizes a group of proxy signers is presented. Meanwhile, our proposed scheme is based on elliptic curve cryptosystem which is more efficient than the corresponding one based on traditional discrete logarithm. 展开更多
关键词 proxy signature nominative proxy signature multi-proxy signature elliptic curve cryptosystem (ECC)
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Efficient and Secure Multi-Signature Scheme Based on Trusted Computing 被引量:1
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作者 HAO Liming YANG Shutang +1 位作者 LU Songnian CHEN Gongliang 《Wuhan University Journal of Natural Sciences》 CAS 2008年第2期180-184,共5页
A new multi-signature scheme was proposed with the extension of the direct anonymous attestation (DAA) protocol supported by trusted computing (TC) technology. Analysis and simulation results show that the signer... A new multi-signature scheme was proposed with the extension of the direct anonymous attestation (DAA) protocol supported by trusted computing (TC) technology. Analysis and simulation results show that the signer's privacy is well protected with dynamic anonymity, the public key and signatures have length independent of the number of signature members, new signers are allowed to join the signature without modifying the public key, and attacks caused by secret key dumping or leaking can be avoided. 展开更多
关键词 multi-signature trusted computing (TC) direct anonymous attestation (DAA) dynamic anonymity
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A New Sequential Digital Multi-Signature Scheme
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作者 Jia Xiaoyun Luo Shoushan +1 位作者 Chen Ping Yuan Chaowei 《China Communications》 SCIE CSCD 2007年第4期66-71,共6页
The paper proposes a new sequential digital multi-signature scheme based on Knapsack public-key cryptosystem,which is different from the existing scheme.The advantages of this scheme over the existing schemes are that... The paper proposes a new sequential digital multi-signature scheme based on Knapsack public-key cryptosystem,which is different from the existing scheme.The advantages of this scheme over the existing schemes are that it simplifies the signature generation process and speeds up the signature verification process.What’s more,the scheme reduces the cost of communication and redundancy operation, and improves efficiency,and can avoid cheating by signer efficiently,so the scheme has very broad application prospects. 展开更多
关键词 KNAPSACK public-key CRYPTOSYSTEM digital signature SEQUENTIAL multi-signature
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Provable Security of ID-Based Proxy Multi-Signature Schemes
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作者 GU Chunxiang ZHU Yuefei ZHAO Tao 《Wuhan University Journal of Natural Sciences》 CAS 2007年第1期87-90,共4页
In the last couple of years, D-based cryptography has got fruitful achievements. Proxy multi-signature allows a designated person, called a proxy signer, to sign on behalf of two or more original signers. In this pape... In the last couple of years, D-based cryptography has got fruitful achievements. Proxy multi-signature allows a designated person, called a proxy signer, to sign on behalf of two or more original signers. In this paper, we present a general security model for ID-based proxy multi-signature (ID-PMS) schemes. Then, we show how to construct a secure ID-PMS scheme from a secure ID-based signature scheme, and prove that the security of the construction can be reduced to the security of the original ID-based signature scheme. 展开更多
关键词 ID-based signature ID-based proxy multi-signature provable security bilinear pairings.
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Improvement of M-U-O and K-P-W proxy signature schemes 被引量:10
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作者 李继国 曹珍富 张亦辰 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第2期145-148,共4页
The concept of proxy signature introduced by Mambo, Usuda, and Okamoto allows a designated person, called a proxy signer, to sign on behalf of an original signer in 1996. However, most existing proxy signature schemes... The concept of proxy signature introduced by Mambo, Usuda, and Okamoto allows a designated person, called a proxy signer, to sign on behalf of an original signer in 1996. However, most existing proxy signature schemes does not support nonrepudiation. In this paper, we propose two secure nonrepudiable proxy signature schemes, which overcome disadvantages of M U O and K P W proxy signature schemes, respectively. The schemes proposed can withstand public key substitution attack and forge attack. In addition, our new schemes have some other advantages such as proxy signature key generation and updating using insecure channels. Our approach can also be applied to other ElGamal like proxy signature schemes. 展开更多
关键词 nonrepudiable DIGITAL signature PROXY signature multi-signature
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Static Digits Recognition Using Rotational Signatures and Hu Moments with a Multilayer Perceptron 被引量:1
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作者 Francisco Solís Margarita Hernández +1 位作者 Amelia Pérez Carina Toxqui 《Engineering(科研)》 2014年第11期692-698,共7页
This paper presents two systems for recognizing static signs (digits) from American Sign Language (ASL). These systems avoid the use color marks, or gloves, using instead, low-pass and high-pass filters in space and f... This paper presents two systems for recognizing static signs (digits) from American Sign Language (ASL). These systems avoid the use color marks, or gloves, using instead, low-pass and high-pass filters in space and frequency domains, and color space transformations. First system used rotational signatures based on a correlation operator;minimum distance was used for the classification task. Second system computed the seven Hu invariants from binary images;these descriptors fed to a Multi-Layer Perceptron (MLP) in order to recognize the 9 different classes. First system achieves 100% of recognition rate with leaving-one-out validation and second experiment performs 96.7% of recognition rate with Hu moments and 100% using 36 normalized moments and k-fold cross validation. 展开更多
关键词 SIGN Language Recognition ROTATIONAL signatureS HU MOMENTS multi-Layer PERCEPTRON
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A=80区奇奇核signature反转现象研究 被引量:1
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作者 程南璞 郑仁蓉 +1 位作者 朱顺泉 文家焱 《西南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2000年第6期648-651,共4页
利用粒子转子模型对A =80区多个奇奇核的晕带能谱进行了实际计算 ,结果表明
关键词 粒子-转子模型 奇奇核 signature反转 晕带能
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A~160区奇奇核signature反转的系统性初探
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作者 文家焱 杨增红 +2 位作者 文学义 程南璞 郑仁蓉 《中山大学学报(自然科学版)》 CAS CSCD 北大核心 2001年第4期55-57,共3页
利用粒子转子模型对A~160质量区奇奇核的signature反转现象的系统性进行了初步的研究,计算结果与实验值符合得很好,并巨表明质子-中子相互作用的逐渐变化对该区奇奇核的signature反转点的系统变化起着主要作用.
关键词 粒子转子模型 奇奇核 signature反转 系统性 质子-中子相互作用 反转机制 反转点
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Multi-features Based Approach for Moving Shadow Detection 被引量:4
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作者 周宁 周曼丽 +1 位作者 许毅平 方宝红 《Journal of Donghua University(English Edition)》 EI CAS 2004年第6期76-80,共5页
In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving... In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving visual object detection. The major novelty of the shadow suppression is the integration of several features including photometric invariant color feature, motion edge feature, and spatial feature etc. By modifying process for false shadow detected, the averaging detection rate of moving object reaches above 90% in the test of Hall-Monitor sequence. 展开更多
关键词 MOVING SHADOW detection multi - features MOVING OBJECT DETECTION
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The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) 被引量:40
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作者 Xiang-Qun Cui Yong-Heng Zhao +52 位作者 Yao-Quan Chu Guo-Ping Li Qi Li Li-Ping Zhang Hong-Jun Su Zheng-Qiu Yao Ya-Nan Wang Xiao-Zheng Xing Xin-Nan Li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-Li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong Liu Hao-Tong Zhang De-Hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang Xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Yan Li Ye-Ping Li Guan-QunLiu Zhi-Gang Liu Huo-Ming Shi Zheng-Hong Tang Qing-Sheng Tao Xiang-Yan Yuan Chao Zhai Jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-Hua Zhou Jie Zhu Si-Cheng Zou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第9期1197-1242,共46页
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effecti... The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects. 展开更多
关键词 techniques: wide field telescope - active optics - multi fiber - spectroscopy survey - data reduction
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A=130号区部分双奇核πh11/2×vh11/2带Signature反转点…
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作者 普运伟 朱顺泉 《青岛大学学报(自然科学版)》 CAS 1997年第A00期38-42,共5页
本文运用轴对称转子加准粒子模型,并在基矢空间中计及p-n相互作用项,对A=130号区部分双奇核πh11/2×vh11/2晕带进行实际计算,结果较好地再现了这些核的signature反转,能谱也与实验值定性相符,由... 本文运用轴对称转子加准粒子模型,并在基矢空间中计及p-n相互作用项,对A=130号区部分双奇核πh11/2×vh11/2晕带进行实际计算,结果较好地再现了这些核的signature反转,能谱也与实验值定性相符,由此进一步证实了双奇核signature反转源于p-n相互作用与科氏力竞争这一机制。 展开更多
关键词 粒子-转子模型 双奇核 signature反转
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多状态可靠性系统动态signature及其剩余寿命分析
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作者 徐凡启 贾旭杰 +1 位作者 松雪莹 苏傲雪 《运筹与管理》 CSSCI CSCD 北大核心 2021年第9期38-42,共5页
系统signature是分析系统可靠性的一个强有力的工具。本文研究了多状态系统的动态signature。Signature概念被拓展到多维的情形,并将其应用于两状态元件下多态关联系统的分析,得到系统在每一状态下的联合生存函数的表达式,探究了系统在... 系统signature是分析系统可靠性的一个强有力的工具。本文研究了多状态系统的动态signature。Signature概念被拓展到多维的情形,并将其应用于两状态元件下多态关联系统的分析,得到系统在每一状态下的联合生存函数的表达式,探究了系统在时刻的动态signature,为处于工作状态的多状态系统在时刻t接受检查,发现其处于l(t)状态并且恰好已发生了q(t)次元件失效,分别给出了两状态元件多态关联系统动态signature及其剩余寿命的表达式。 展开更多
关键词 系统可靠性 signature 动态signature 多状态系统 剩余寿命
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A Comparative Study of Acute Hemodynamic Effects of Multi -site Cardiac Pacing in patients with cardiac function NYHA class ⅠtoⅡ without bundle branch block 被引量:2
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作者 朱参战 崔长琮 +5 位作者 张全发 薛小临 刘维维 刘引会 《South China Journal of Cardiology》 CAS 2001年第2期101-105,共5页
Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS ... Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS 7, Ⅲ°AVB 5) undergoing pacemaker implantation. Right ventricular apex (RVA), right ventricular outflow tract (RVOT), right ventricular bifocal (RV-Bi), left ventricular base (LVB) and bi -ventricular (Bi-Ⅴ) pacing at 60 -80 ppm were done in VVI mode prior to implantation of DDD pacemaker. The cardiac index (CI), mean pulmonary artery pressure (mPAP) and pulmonary capillary wedge pressure (PCWP) were measured with Swan - Ganz thermodilution catheter after 5 minutes of each pacing mode. Results (1) Comparing to pacing at RVA (CI: 2. 41± 0. 38 L/min per m2, PCWP: 16. 7 ±3.3 mmHg), the CI increased and the PCWP decreased significantly in pacing at RVOT(CI: 2. 63 ± 0.46, PCWP: 13. 8±2. 3), LVB(CI: 2. 78±0.52, PCWP: 14. 4±3.1), RV-Bi(CI: 2. 83±0.57, PCWP: 12. 8± 2. 5) and Bi -Ⅴ pacing (CI: 2. 94± 0.60, PCWP: 12. 7±2. 5), P < 0. 01, respectively. (2) The CI of RV-Bi and Bi-Ⅴ pacing was higher than that of RVOT and LVB pacing, the PCWP was lower, P < 0. 05, respectively. (3) There was no significant difference between RV - Bi pacing and Bi-Ⅴ pacing in CI and PCWP. Conclusion There is no significant difference between RV - Bi pacing and Bi -V pacing in the acute hemodynamic effects; however,dual - site pacing is much better than single site pacing in that aspect for patients with cardiac function NYHA class Ⅰ to Ⅱ without BBB. Among single site pacing, the RVOT and LVB pacing is better than RVA pacing in cardiac function. 展开更多
关键词 multi - site cardiac pacingHemodynamics
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Research on A Master - slave Multi - microcomputers Control System for Hollow Spindle Fancy Yarn Spinning Machine
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作者 李志蜂 陈子展 阵瑞琪 《Journal of China Textile University(English Edition)》 EI CAS 1999年第1期49-52,共4页
In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardwar... In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardware construction, is introduced. Spinning experiments show that the system achieves satisfactory result. This system can solve the diftkultles of mechatronical fusion between domestic hollow splndk fancy yarn spuming muchine and its microcomputer control technology. 展开更多
关键词 hollow SPINDLE FANCY YAM spinning machine mechatrvnical fusion MASTER - SLAVE multi - microcomputers control system PC - BUS.
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On the Representation of Multi-layer Woven Structure
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作者 易洪雷 丁辛 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期14-16,共3页
A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the rein... A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the reinforcement of textile composites, the relationships among the structural parameters are derived for different binding patterns of the fabric structure. The conditions, which meet the requirements of structural cell stability,are also discussed. 展开更多
关键词 multi - layer woven FABRIC structural parame-ter BINDING PATTERN TEXTILE composite .
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奇奇核^76Rb,^80Rb的Signature反转现象研究
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作者 文家焱 普运伟 《西南师范大学学报(自然科学版)》 CAS CSCD 北大核心 1998年第5期538-542,共5页
关键词 -奇核 铷76 signature反转 铷80
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