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生成量子稳定子码的种子生成器
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作者 肖芳英 陈汉武 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2010年第1期52-57,共6页
为了解决生成量子稳定子码的码字时需先找出种子生成器的问题,将寻找种子生成器转化为解线性方程组及线性空间中向量组线性相关和线性无关问题,提出了快速判决法、排序查找法和求解方程组方法来验证找到的算子是否为合法的种子生成器.... 为了解决生成量子稳定子码的码字时需先找出种子生成器的问题,将寻找种子生成器转化为解线性方程组及线性空间中向量组线性相关和线性无关问题,提出了快速判决法、排序查找法和求解方程组方法来验证找到的算子是否为合法的种子生成器.将稳定子与种子生成器同时标准化可以快速得到量子稳定子码的编码电路.给出了稳定子码种子生成器总数和编码电路所需要的2-qubit和1-qubit门数量.该方法既能用于同时包含Ⅰ型和Ⅱ型生成元的量子稳定子码,又能用于仅含Ⅰ型生成元的量子稳定子码,得到的种子生成器仅含X算子,故编码电路简单. 展开更多
关键词 量子纠错码 稳定子 种子生成 编码电路
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SmartSeed:一种面向模糊测试的智能化种子生成策略
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作者 吕晨阳 李宇薇 纪守领 《黑龙江大学工程学报》 2021年第3期90-108,共19页
基于变异的模糊测试工具能通过变异初始种子文件来生成许多输入文件(测试样例),使用这些输入文件测试目标程序,挖掘程序的潜在崩溃。现存的种子选择策略的效率似乎并不比随机选择种子文件作为初始种子集更高效。因此,提出一种新颖、通... 基于变异的模糊测试工具能通过变异初始种子文件来生成许多输入文件(测试样例),使用这些输入文件测试目标程序,挖掘程序的潜在崩溃。现存的种子选择策略的效率似乎并不比随机选择种子文件作为初始种子集更高效。因此,提出一种新颖、通用的模糊测试种子生成系统SmartSeed,用以提升模糊测试的效率。将SmartSeed与AFL结合,在12个具有不同输入文件格式的开源程序上测试其漏洞挖掘性能,进一步将SmartSeed与其它模糊测试工具结合以测试其兼容性。通过实验测试,SmartSeed被证明具有:①SmartSeed能生成具有不同输入格式的种子文件,并能在绝大多数测试程序上显著提升模糊测试工具的漏洞挖掘效率;②SmartSeed与现行主流模糊测试工具能够很好兼容。实验结果表明,SmartSeed可比现存最优种子选择策略多发现超过一倍数量的程序崩溃,并多发现5040条执行路径。根据SmartSeed的报告结果,申请得到16个新的漏洞CVE编号。 展开更多
关键词 模糊测试 漏洞挖掘 种子生成
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基于机器学习的模糊测试种子输入优化
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作者 王敏 冯登国 +1 位作者 程亮 张阳 《计算机系统应用》 2021年第6期1-8,共8页
模糊测试作为一种自动化检测应用程序漏洞的方法,常常被用来检测各种软件以及计算机系统的漏洞挖掘中.而种子文件质量的高低对于模糊测试的效果而言至关重要.所以本文提出了一种基于机器学习的模糊测试种子输入的生成方法,利用样本输入... 模糊测试作为一种自动化检测应用程序漏洞的方法,常常被用来检测各种软件以及计算机系统的漏洞挖掘中.而种子文件质量的高低对于模糊测试的效果而言至关重要.所以本文提出了一种基于机器学习的模糊测试种子输入的生成方法,利用样本输入和基于机器学习的技术来学习样本输入的规则和语法.并利用学到的规则和语法来生成全新的种子输入.我们还提出了一个采样方法.使得这些新的种子输入的覆盖率较之前有了明显提升. 展开更多
关键词 模糊测试 机器学习 代码覆盖率 种子生成 Transformer模型 attention机制
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Callus Induction and Plant Regeneration from Mature Seeds of Perennial Ryegrass 被引量:15
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作者 曾升坚 卞建春 +2 位作者 方钲 张冬霞 邹新海 《Agricultural Science & Technology》 CAS 2009年第6期33-36,共4页
Objective The aim was to explore callus induction and plant regeneration of perennial ryegrass, as well as provide the foundation for transgenic research on perennial ryegrass.[ Methed] Mature seeds of perennial ryegr... Objective The aim was to explore callus induction and plant regeneration of perennial ryegrass, as well as provide the foundation for transgenic research on perennial ryegrass.[ Methed] Mature seeds of perennial ryegrass were used as explants to study the effects of different hormone compositions on callus induction, proliferation and plant differentiation. Result The result showed that the induction rate achieved its highest on 2,4-D of 8 mg/L combining with 6-BA of 0.025 mg/L, which was up to 56.42%. Callus were differentiated after two to three generations, the highest differentiation rate 34.14% was achieved in the medium contained MS medium with 6-BA of 2 mg/L, and the differentiation rate was obviously affected by the callus condition after proliferation. The root inducing medium, containing 0.5 mg/L NAA and MS medium with half of macroelement, gained 98% root inducing rate. Conclusien A high frequency genetic regeneration system was established. 展开更多
关键词 Perennial ryegrass Mature seed: Tissue culture Plant regeneration
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基于流线的流场可视化绘制方法综述 被引量:3
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作者 张倩 肖丽 《计算机科学》 CSCD 北大核心 2021年第12期1-7,共7页
流场可视化是科学计算可视化中一个重要的分支,主要对计算流体动力学的模拟计算结果进行可视化,给研究人员提供视觉上直观可见的图形图像,方便研究人员进行分析。流场可视化的已知技术包括基于几何的方法(如流线和粒子追踪法)以及基于... 流场可视化是科学计算可视化中一个重要的分支,主要对计算流体动力学的模拟计算结果进行可视化,给研究人员提供视觉上直观可见的图形图像,方便研究人员进行分析。流场可视化的已知技术包括基于几何的方法(如流线和粒子追踪法)以及基于纹理的方法(如LIC、噪声点、IBFV等)。流线可视化是流场可视化的一个重要且常用的几何可视化手段。在流线可视化的研究中,流线的放置是整个流线可视化的重点,流线的数目和位置影响了整个可视化效果。当流线放置过多时,会造成视觉的杂乱;而流线放置过少会使流场信息表达不完整,无法传递完整的信息给领域专家。为了实现对科学数据的精确显示,流线可视化产生了两个重要的研究方向:种子点的放置和流线的约减。文中介绍了种子点放置方法和流线的约减方法的相关研究,总结了在2D和3D流场上出现的一些问题和采取的解决方案,并针对日益增长的科学数据,提出流线可视化下一步需要解决的问题。 展开更多
关键词 流线放置 种子生成策略 流线约减 流场可视化 科学计算可视化
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Effects of the anti-tumor composition ofthe acetoacetate extract of vitex negundoseed on the growth of human cervical carcinomaxenografts in nude mice 被引量:2
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作者 Yanlin Cai Zhongdong Chen +3 位作者 Aiqiong Tang Bin Jiang Zhaohua Fan Jun Bai 《The Chinese-German Journal of Clinical Oncology》 CAS 2014年第3期105-109,共5页
Objective: The aim of our study was to investigate the effects of the anti-tumor composition of the acetoacetate extract of Vitex Negundo Seed (EVn-50) on the growth of human cervical carcinoma HeLa cells xenograft... Objective: The aim of our study was to investigate the effects of the anti-tumor composition of the acetoacetate extract of Vitex Negundo Seed (EVn-50) on the growth of human cervical carcinoma HeLa cells xenografts in nude mica and its possible molecular mechanism. Methods: Models of human cervical cancer HeLa cells xenografts transplanted subcuta- neously in nude mice were established and randomly divided into 7 groups (each group including 5 nude mice): saline group, Taxol group, EVn-50 group, comp-6 group, comp-7 group, comp-8 group and comp-10 group. The volume and weight of Xe- nograts were observed and compared. The alteration of the weight of nude mice, and the change of serum levels ofLDH, ALT, Cr and WBC counts were examined and compared. The apoptotic rate of human cervical carcinoma HeLa cells xenografts was analyzed by FCM. The expressions of P53 and Bcl-2 proteins of HeLa cells xenografts were determined by Western blot- ting. Results: EVn-50 and its fractionated extracts could significantly suppress the increasing volume and weight of human cervical carcinoma HeLa cells xenografts in nude mice models in time-dependent manner, yet had no significant effect on the weight of nude mice, the serum levels of LDH, ALT, Cr and WBC were counted. When the xenografts were treated with EVn-50 and its fractionated extracts for 16 days, the apoptotic rate of xenografts cells were significantly increased, and the expression of P53 protein was up-regulated and protein level of Bcl-2 was decreased. Conclusion: EVn-50 and its fractionated extracts could suppress the growth of human cervical carcinoma HeLa cells xenografts in nude mice, which may be related to its pro- motion on xenografts cells apoptosis through down-regulation of Bcl-2 expressionPand activation of P53 expression. 展开更多
关键词 cervical cancer EVn-50 XENOGRAFTS apoptosis
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Herbicidal Activities of Seven Native Plants on the Germination and Growth of Phalaris minor, Echinochloa crusgalli, Portulaca oleracea and Lactuca sativa
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作者 Abdulrohman AL-Humaid Ragab Abdelmohsen El-Mergaw 1,2 《Journal of Agricultural Science and Technology(A)》 2014年第10期843-852,共10页
Plant extracts could turn out to be herbicides used in weed control. We evaluated the herbicidal effect of seven plants from the Al-Qassim Region of Saudi Arabia on germination and growth of Phalaris minor, Echinochlo... Plant extracts could turn out to be herbicides used in weed control. We evaluated the herbicidal effect of seven plants from the Al-Qassim Region of Saudi Arabia on germination and growth of Phalaris minor, Echinochloa crusgalli, Portulaca oleracea and Lactuca sativa. In the laboratory, plant extracts at 5, 10, 20 and 40 g/L inhibited the germination and seedling growth of test seeds. P. minor and P. oleracea were more sensitive to the extracts than L. sativa and E. crusgalli. The germination of either P. minor or P. oleracea were completely inhibited by Prosopisjuliflora at 10 g/L and by Rumex vesicarius and Teucrium baccatus at 20 g/L. Extract of Pulicaria undulate completely inhibited germination of target seeds at concentrations ranged from l 0 g/L to 40 g/L. The rank order of bioactivity was Prosopis jul(17ora 〉 Pulicaria undulata 〉 Rumex vesicarius 〉 Withania somnifera 〉 Teucrium baccatus 〉 Artemisia monosperma 〉 Anvillea garcinii. In the greenhouse trial, the extracts of seven plant species at 30, 60 and 90 g/L reduced growth of six-weeks-old target plants. Anvillea garcinii and Prosopisjuliflora showed the greatest effects. At 90 g/L, the reduction in the growth of target species reached between 20% and 30% for Anvillea garcinii and between I 1% and 25% for Prosopis juliflora. Overall, Prosopis juliflora, Pulicaria undulata, Anvillea garcinii and Rumex vesicarius had potential for use as natural herbicides or for development as novel plant-derived herbicides. 展开更多
关键词 Natural herbicide germination bioassay greenhouse bioassay Saudi Arabia Prosopis juliflora Pulicaria undulata Rumex vesicarius Anvillea garcinii.
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乐鱼教你做电影专辑
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《计算机与网络》 2009年第6期25-25,共1页
网上看电影,资源太多,纵使再大的硬盘都会很快装满,你是否在为无法保存自己喜爱的影片而发愁呢?是否因为时间久淡忘了影片的名称而烦恼呢?或许你是一位怀旧情结浓厚的电影迷,专喜欢一些上世纪七十年代。八十年代的经典电影;或许... 网上看电影,资源太多,纵使再大的硬盘都会很快装满,你是否在为无法保存自己喜爱的影片而发愁呢?是否因为时间久淡忘了影片的名称而烦恼呢?或许你是一位怀旧情结浓厚的电影迷,专喜欢一些上世纪七十年代。八十年代的经典电影;或许你对某个导演的作品情有独钟,想自己长久保存他的电影……这些烦恼让乐鱼帮你解决吧。 展开更多
关键词 乐鱼影音盒 生成种子文件 电影专辑 软件
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