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The “Dead Universe” Theory: Natural Separation of Galaxies Driven by the Remnants of a Supermassive Dead Universe
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作者 Joel Almeida 《Natural Science》 2024年第6期65-101,共37页
This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This per... This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This perspective challenges the conventional Big Bang theory, particularly concerning dark matter, the expansion of the universe, and the interpretation of phenomena such as gravitational waves. 展开更多
关键词 Dead Universe Theory Heat Death of the Universe Big Bang Theory Universe’s Ultimate Fate Universe Expansion Big Freeze Universe Cosmological Models end of Universe Theories Natural Galaxy Drift Future of the Universe Universe Cooling Down Cosmology and Entropy
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基于B/S架构的高校作业管理系统设计与实现
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作者 周文俊 王国印 《现代计算机》 2024年第2期98-102,共5页
设计基于阿里云服务器实现B/S架构的高校作业管理系统,完成了高校学生的作业发布、作业提交、作业预览、作业评价等基本功能。该系统使用前后端分离的架构,其中主要使用Vue框架、Flask框架、MySQL数据库等组件,详细地使用Vue实现前端服... 设计基于阿里云服务器实现B/S架构的高校作业管理系统,完成了高校学生的作业发布、作业提交、作业预览、作业评价等基本功能。该系统使用前后端分离的架构,其中主要使用Vue框架、Flask框架、MySQL数据库等组件,详细地使用Vue实现前端服务,使用Python+Flask提供后端服务,使用MySQL存储相关数据。测试结果表明,该系统基本能够满足高校日常作业管理的需求,包括教师及学生角色的注册和登录、学生作业管理、教师发布作业及批改作业等功能。 展开更多
关键词 B/s架构 前后端分离 作业管理
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China's English Learners' Verbal Phrase Acquisition Research Based on the Corpus——“at last”and“in the end”as an Example
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作者 张俊梅 柴晶 《海外英语》 2013年第24期262-263,287,共3页
This study is a comparative research based on corpus. This article compares China's English learners with English na?tive speakers about the use of "at last" and "in the end" from three aspects... This study is a comparative research based on corpus. This article compares China's English learners with English na?tive speakers about the use of "at last" and "in the end" from three aspects: frequency of use, location, semantic prosody. The study shows that the use of the two words are greatly different between China's English learners and English native speakers. In addition, this study discusses about causes of obvious differences and teaching enlightenments. 展开更多
关键词 at LAsT in the end" China’s English LEARNERs
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基于SpringBoot+Vue的在线考试系统设计与实现 被引量:1
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作者 姜一波 《无线互联科技》 2023年第23期68-71,共4页
随着互联网技术的不断发展,在线考试模式得到了更为广泛的应用,为满足教师和学生对于快捷出题、快速批改、诚信考试的需求,文章基于前后端分离的思想,前端使用Vue技术搭建,后台采用SpringBoot+MybatisPlus,开发一个基于B/S模式的在线考... 随着互联网技术的不断发展,在线考试模式得到了更为广泛的应用,为满足教师和学生对于快捷出题、快速批改、诚信考试的需求,文章基于前后端分离的思想,前端使用Vue技术搭建,后台采用SpringBoot+MybatisPlus,开发一个基于B/S模式的在线考试系统。系统实现单选、多选、判断、填空等题型的自动判分,并且提供主观题错题解析、错题集合等功能。系统安全稳定、成本低、运行效率高。 展开更多
关键词 springBoot Vue在线考试系统 B/s架构 前后端分离
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Role of the advanced glycation end products receptor in Crohn's disease inflammation 被引量:2
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作者 Rachele Ciccocioppo Alessandro Vanoli +13 位作者 Catherine Klersy Venerina Imbesi Vincenzo Boccaccio Rachele Manca Elena Betti Giuseppina Cristina Cangemi Elena Strada Roberta Besio Antonio Rossi Colomba Falcone Sandro Ardizzone Paolo Fociani Piergiorgio Danelli Gino Roberto Corazza 《World Journal of Gastroenterology》 SCIE CAS 2013年第45期8269-8281,共13页
AIM:To investigate the level of mucosal expression and the involvement of the receptor for the advanced glycation end products(RAGE)in delayed apoptosis and tumor necrosis factor(TNF)-αproduction in Crohn’s disease(... AIM:To investigate the level of mucosal expression and the involvement of the receptor for the advanced glycation end products(RAGE)in delayed apoptosis and tumor necrosis factor(TNF)-αproduction in Crohn’s disease(CD).METHODS:Surgical and endoscopic specimens from both inflamed and non-inflamed areas of the ileum and/or colon were collected from 20 and 14 adult CD patients,respectively,and used for the assessment of RAGE expression by means of immunohistochemistry and western blotting analysis.Normal tissues from 21 control subjects were used for comparison.The same polyclonal anti-human RAGE antibody(R and D System)was used in all experimental conditions.RAGE staining was quantized by a score including both the amount of positive cells and intensity of immunoreactivity;cellular pattern was also described.The effects of RAGE blocking on apoptotic rate and TNF-αproduction were investigated on immune cells freshly isolated from CD mucosa and incubated both with and without the muramyl dipeptide used as antigenic stimulus.Statistical analysis was performed via the test for trend,with regression models to account for intra-patient correlations.A 2-sided P<0.05 was considered significant.RESULTS:In inflamed areas,RAGE expression in both the epithelial and lamina propria compartments was higher than control tissues(P=0.001 and 0.021,respectively),and a cluster of positive cells were usually found in proximity of ulcerative lesions.Similar results were obtained in the lamina propria compartment of non-inflamed areas(P=0.025).The pattern of staining was membranous and granular cytosolic at the epithelial level,while in the lamina propria it was diffuse cytosolic.When evaluating the amount of protein expression by immunoblotting,a significant increase of both surface area and band intensity(P<0.0001 for both)was observed in CD inflamed areas compared to control tissue,while in non-inflamed areas a significant increase was found only for band intensity(P<0.005).Moreover,a significantly lower expression in noninflamed areas in comparison with inflamed areas was found for both surface area and band intensity(P<0.0006 for both).Finally,RAGE blocking largely affects both the apoptotic rate of mucosal cells(towards an increase in both non-inflamed and inflamed areas of P<0.001 and<0.0001,respectively)and TNF-αsecretion(towards a decrease in both non-inflamed and inflamed areas of P<0.05 and<0.01,respectively),mainly in the presence of antigenic stimulation.CONCLUSION:RAGE is up-regulated in CD,especially in inflamed areas,and it appears to play a role in the mechanisms involved in chronic inflammation. 展开更多
关键词 Apoptosis Crohn’s disease CHRONIC INFLAMMATION IMMUNOHIsTOCHEMIsTRY RECEPTOR for advanced glycation end products TUMOR NECROsIs factor-α
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Synthesis and mesomorphic properties of fluorinated Schiff's base liquid crystals containing vinyl end groups 被引量:1
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作者 Qiang Wei Siquan Zhu +4 位作者 Lin Shi Lipei Zhang Xiaotao Yuan Hui Cao Huai Yang 《Journal of University of Science and Technology Beijing》 CSCD 2007年第4期373-377,共5页
Three kinds of fluorinated Schiff's base esters, 4-allyloxy-2-X-6-X-benzoic acid 4-[(2, 3, 4-trifluorophenylimino)methyl]phenyl ester, where X=H or F, were synthesized and characterized. Their chemical structures w... Three kinds of fluorinated Schiff's base esters, 4-allyloxy-2-X-6-X-benzoic acid 4-[(2, 3, 4-trifluorophenylimino)methyl]phenyl ester, where X=H or F, were synthesized and characterized. Their chemical structures were identified by Fourier transform infrared spectroscopy (FTIR) and ^1H nuclear magnetic resonance (^1H NMR). Their mesomorphic properties were studied by polarized optical microscopy (POM) and differential scanning calorimetry (DSC). It was found that all the three compounds exhibited enantiotropic nematic phases only. And their cleating point temperature and thermal range of mesophase decreased with the number of fluorine atoms on the rigid core of the compounds; while their melting point temperature showed no distinct regularity. 展开更多
关键词 sYNTHEsIs schiff's base fluorinated liquid crystal vinyl end group
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端面密封材料S-07不锈钢滑动摩擦学行为的分子动力学模拟 被引量:1
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作者 王权 庄宿国 +2 位作者 黄丹 朱正兴 刘秀波 《润滑与密封》 CAS CSCD 北大核心 2023年第3期141-146,共6页
为探究端面密封材料S-07不锈钢在不同参数下的摩擦学行为,构建纳米尺度下S-07不锈钢的摩擦磨损模型,以对偶件的压入深度和滑动速度作为变量,研究S-07不锈钢表面摩擦学性能及形貌变化。结果表明:随着摩擦相对滑动速度的增加(50、100、150... 为探究端面密封材料S-07不锈钢在不同参数下的摩擦学行为,构建纳米尺度下S-07不锈钢的摩擦磨损模型,以对偶件的压入深度和滑动速度作为变量,研究S-07不锈钢表面摩擦学性能及形貌变化。结果表明:随着摩擦相对滑动速度的增加(50、100、150 m/s),S-07不锈钢磨损表面粗糙度降低;随着对偶件压入深度(0.3、0.6、0.9 nm)的增大,摩擦因数呈上升趋势;磨损量随压入深度增大而增大,随滑动速度上升呈下降趋势。在微观尺度上,从位错、塑性变形等角度解释了在不同磨损条件下S-07不锈钢性能变化的原因,为该材料适用摩擦工况的选择提供了理论参考。 展开更多
关键词 端面密封 摩擦学行为 分子动力学模拟 s-07不锈钢
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Rapid Amplification of 5′ cDNA End of S. Liaotungensis Choline Monooxygenase Using Inverse PCR RACE 被引量:1
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作者 李秋莉 Gao Xiaorong +3 位作者 FAN Qi Yuan Xiaodong Liu Dawei An Lijia 《High Technology Letters》 EI CAS 2002年第1期5-7,共3页
Based on part of a known cDNA sequence of Suaeda Liaotungensis choline monooxygenase, the authors successfully cloned the 5′ cDNA end of Suaeda Lianotungensis choline monooxygenase using Inverse PCR RACE with a speci... Based on part of a known cDNA sequence of Suaeda Liaotungensis choline monooxygenase, the authors successfully cloned the 5′ cDNA end of Suaeda Lianotungensis choline monooxygenase using Inverse PCR RACE with a specially designed 5′-phosphated RT primer and two pairs of specific inverse PCR primers. Compared with the anchored PCR RACE, inverse PCR RACE has better specificity and higher amplification. 展开更多
关键词 DNA 放大 反演PCR RACE应用
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Unicentric Castleman's disease associated with end stage renal disease caused by amyloidosis
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作者 Eray Eroglu Ismail Kocyigit +5 位作者 Aydin Unal Murat Hayri Sipahioglu Hulya Akgun Leylagul Kaynar Bulent Tokgoz Oktay Oymak 《World Journal of Clinical Cases》 SCIE 2017年第3期119-123,共5页
Castleman's disease(CD), also known as angiofolicular lymph node hyperplasia, is a rare heterogenous group of lymphoproliferative disorders. Histologically, it can be classified as hyaline vascular type, plasma ce... Castleman's disease(CD), also known as angiofolicular lymph node hyperplasia, is a rare heterogenous group of lymphoproliferative disorders. Histologically, it can be classified as hyaline vascular type, plasma cell type, or mixed type. Clinically two different subtypes of the CD are present: Unicentric and multicentric. Unicentric CD is generally asymptomatic and associated with hyaline vascular type, and its diagnoses depend on the localized lymphadenopathy on examination or imaging studies. However, multicentric CD presents with generalized lymphadenopathy and systemic symptoms including malaise, fever, night sweats, weight loss, and it is associated with the plasma cell type and mix type. Herein, we report a patient with unicentric CD of the plasma cell type without systemic symptoms, who developed end stage renal failure caused by amyloidosis 6 years after onset of CD. 展开更多
关键词 Castleman’s disease AMYLOIDOsIs Plasma cell INFLAMMATION end stage renal disease
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ZTE Plans to Deploy Colombia's First Mobile WiMAX Network by the End of 2008
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《ZTE Communications》 2008年第3期62-62,共1页
ZTE Corporation announced on August19,2008 that it had clinched an exclusive bid from Colombia’s leading operator
关键词 WIMAX ZTE Plans to Deploy Colombia’s First Mobile WiMAX Network by the end of 2008
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Fun and Merriment at the Rainbow’s End
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作者 LIU HUANZHI & XU YING 《China Today》 2011年第2期74-81,共8页
THOUGH many times eclipsed by its more famous neighboring cities of Beijing and Tianjin, Hebei Province hardly delivers a lack luster performance where local color and beautiful environs are concerned.
关键词 Fun and Merriment at the Rainbow s end
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基于END误差下EV回归模型中LS估计量的强相合性
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作者 丁洋 葛梅梅 邓新 《滁州学院学报》 2021年第5期18-23,共6页
推广的负象限相依(END)变量是一类包含独立变量、负相协(NA)变量、负象限相依(NOD)变量等在内的非常广泛的相依变量,在保险与金融数学、复杂性系统、可靠性理论、生存分析等领域都有着广泛的应用。为了建立EV回归模型中未知参数LS估计... 推广的负象限相依(END)变量是一类包含独立变量、负相协(NA)变量、负象限相依(NOD)变量等在内的非常广泛的相依变量,在保险与金融数学、复杂性系统、可靠性理论、生存分析等领域都有着广泛的应用。为了建立EV回归模型中未知参数LS估计量的强相合性,在假设误差是END随机变量序列的前提下,利用END变量的Bernstein型不等式以及随机变量的截尾技术,得出结论。所得结果不仅推广了NA随机变量的相应研究,也完善了概率极限理论。 展开更多
关键词 end随机变量 EV回归模型 A.s.收敛
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15th China’s International Chemical Fiber Conference Ended in Hangzhou
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《China Textile》 2009年第7期17-17,共1页
The 15th China’s International Chemical Fiber Conference was held at Hangzhou, Zhejiang Province on June 10th-12th, 2009. The theme of the conference is "Financial Crisis and Chemical Fiber Industry". Hundr... The 15th China’s International Chemical Fiber Conference was held at Hangzhou, Zhejiang Province on June 10th-12th, 2009. The theme of the conference is "Financial Crisis and Chemical Fiber Industry". Hundreds of delegates 展开更多
关键词 PTA In s International Chemical Fiber Conference ended in Hangzhou China
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China to Become U.S. Third Largest Export Market by Year End
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《China Textile》 2007年第9期10-11,共2页
China is likely to become the third biggest importer of goods from the United States within a year after five straight years as the fastest growing U.S. export market. Chinese Vice Minister of Commerce Gao Hucheng sa... China is likely to become the third biggest importer of goods from the United States within a year after five straight years as the fastest growing U.S. export market. Chinese Vice Minister of Commerce Gao Hucheng said on Thursday that China was expected to overtake Japan as the third largest U.S. export market at the end of this year or early next year. 展开更多
关键词 China to Become U.s Third Largest Export Market by Year end than high
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S波段3.3 MW脉冲磁控管的可靠性技术研究
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作者 刘宇荣 李胜明 +10 位作者 葛锐 潘峰 徐青松 陈小慧 李永明 黄俊杰 王少哲 邹建军 覃奀垚 黄浩 王琦龙 《真空电子技术》 2023年第3期25-27,38,共4页
在S波段3.3 MW脉冲磁控管研制过程中,连续多支磁控管在工作比为1.05‰的条件下工作不足100 h,阳极端盖出现明显的氧化现象,经分析轴向电子轰击端盖产生局部高温是引起磁控管阳极端盖氧化的一个重要原因。本文对阴极发射体端部结构进行改... 在S波段3.3 MW脉冲磁控管研制过程中,连续多支磁控管在工作比为1.05‰的条件下工作不足100 h,阳极端盖出现明显的氧化现象,经分析轴向电子轰击端盖产生局部高温是引起磁控管阳极端盖氧化的一个重要原因。本文对阴极发射体端部结构进行改进,仿真分析及实验结果证明了改进后的结构可实现对轴向电子的有效抑制。改进后的磁控管在脉冲电压为47.5 kV、脉冲电流为120 A、脉冲宽度为4.2μs、工作比为1.2‰的条件下,输出脉冲功率大于3.3 MW,磁控管已稳定工作超300 h,阳极端盖无氧化现象发生。实验结果为进一步提升磁控管技术性能及推广应用打下了良好基础。 展开更多
关键词 s波段 磁控管 阳极端盖 轴向电子 氧化现象
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200 Gbit/s SR4光收发模块的研究与设计
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作者 向华 罗超 +1 位作者 孙洪君 孙莉萍 《电子设计工程》 2023年第20期73-76,81,共5页
针对互联网的高速发展,现代数据中心寻求一种高速率、高带宽的信息传输方式。光纤通信因其大容量以及低损耗的特点脱颖而出。光收发模块是光纤通信系统中完成光电信号转换的关键部件。该文重点分析了200 Gbit/s SR4光收发模块的基本原理... 针对互联网的高速发展,现代数据中心寻求一种高速率、高带宽的信息传输方式。光纤通信因其大容量以及低损耗的特点脱颖而出。光收发模块是光纤通信系统中完成光电信号转换的关键部件。该文重点分析了200 Gbit/s SR4光收发模块的基本原理,主要阐述了模块的发射单元、接收单元、管理单元及数字处理芯片4个部分。测试了200 Gbit/s SR4光收发模块的主要指标,测试结果表明,模块可以满足协议的各项要求。 展开更多
关键词 数据中心 光纤通信系统 200 Gbit/s光收发模块 发射端 接收端
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基于初始电流行波相位的多端混合直流线路单端保护方案
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作者 戴志辉 牛宝仪 +3 位作者 邱宏逸 奚潇睿 韩哲宇 韦舒清 《高电压技术》 EI CAS CSCD 北大核心 2024年第2期649-659,I0003-I0010,共19页
为了解决LCC-MMC型多端混合直流系统线路保护存在的问题,提出一种基于初始电流行波相位的多端混合直流线路单端保护方案。首先基于多端混合直流输电线路发生不同位置和类型的故障工况,推导直流线路入射电压行波的解析式并计算其高频段... 为了解决LCC-MMC型多端混合直流系统线路保护存在的问题,提出一种基于初始电流行波相位的多端混合直流线路单端保护方案。首先基于多端混合直流输电线路发生不同位置和类型的故障工况,推导直流线路入射电压行波的解析式并计算其高频段相位。其次结合线路边界行波折反射原理和测量波阻抗特性,提出利用初始电压行波相位的区内外识别判据,并根据雷击和短路故障的入射行波低频相位特性构建雷击干扰判据。在PSCAD/EMTDC中搭建昆柳龙多端混合直流系统模型进行验证,证明所提方案仅利用单端量信息即可满足故障判断和选线要求,满足速度性的同时具备一定的抗过渡电阻能力(500Ω)。 展开更多
关键词 多端混合直流 电流行波相位 线路故障 s变换 单端量保护
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“S”形刃球头立铣刀的研究(Ⅰ)──数学模型 被引量:9
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作者 易德明 廖钢 +2 位作者 龙美彪 林丞 杨受章 《湖南大学学报(自然科学版)》 EI CAS CSCD 1996年第2期65-69,共5页
在分析球头立铣刀刃磨方法的基础上,建立了“S”形刃球头立铣刀前、后刀面以及切削刃的数学模型.模型的建立对“S”形刃球头立铣刀几何参数的分析及优化、切削机理的研究、刃磨参数的选择以及刃磨装置的设计都将具有理论意义;对加... 在分析球头立铣刀刃磨方法的基础上,建立了“S”形刃球头立铣刀前、后刀面以及切削刃的数学模型.模型的建立对“S”形刃球头立铣刀几何参数的分析及优化、切削机理的研究、刃磨参数的选择以及刃磨装置的设计都将具有理论意义;对加快“S”形刃球头立铣刀的国产化制造具有实用价值. 展开更多
关键词 数学模型 刃磨 球头立铣刀 铣刀
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基于Ajax和SVG的Web远程实时监控系统 被引量:22
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作者 吴灿培 胡顺豪 +1 位作者 王海航 沈先海 《计算机工程与设计》 CSCD 北大核心 2011年第9期3004-3007,3013,共5页
以ASP.NET为平台,使用Ajax和SVG实时显示技术完成了基于Web的B/S模式远程监控,实现了跨操作平台的网站式远程实时监控系统,将实时监测与控制系统构筑于Internet之上,通过Internet实现对现场设备的实时远程监控、设备故障诊断与调试。设... 以ASP.NET为平台,使用Ajax和SVG实时显示技术完成了基于Web的B/S模式远程监控,实现了跨操作平台的网站式远程实时监控系统,将实时监测与控制系统构筑于Internet之上,通过Internet实现对现场设备的实时远程监控、设备故障诊断与调试。设计的前端设备远程监控器可实时监控现场设备的工况,方便组网实现多监控点的实时监控,易于扩展。应用结果表明,该系统有良好的实时性、可靠性、交互性和扩展性。 展开更多
关键词 Web B/s 前端设备远程监控器 AJAX 可伸缩矢量图形 远程实时监控
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一种球头铣刀“S”形刃口曲线的数学建模方法 被引量:4
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作者 庞思勤 乔小峰 +1 位作者 王西彬 彭松 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2014年第5期44-49,共6页
为了简化球头铣刀'S'形刃口的数学模型,推导两个空间平面与球面相交而成的复合型刃口曲线方程,提出并应用了'单球法'和'双球法'两种数学建模方法,并推导了球头铣刀球面部分平面刃口曲线偏转角和螺旋角的数学表... 为了简化球头铣刀'S'形刃口的数学模型,推导两个空间平面与球面相交而成的复合型刃口曲线方程,提出并应用了'单球法'和'双球法'两种数学建模方法,并推导了球头铣刀球面部分平面刃口曲线偏转角和螺旋角的数学表达式.结果表明:偏转角和螺旋角两者相等,可以简化球面部分平面刃口曲线的数学模型,既降低了平面刀刃曲线的推导过程的复杂性,同时又为两个或多个空间平面与球头铣刀球面部分相交而成的复合型刃口曲线方程的建模提供了一种有效方法. 展开更多
关键词 球头铣刀 s”形刃口曲线 刀刃曲线 数学模型
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