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A holographic optical communication system based on RSA algorithm and quaternion function
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作者 YANG Peng HAN Jianning 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期338-343,共6页
A facile encryption way was successfully applied to the holographic optical encryption system with high speed,multidimensionality,and high capacity,which provided a better security solution for underwater communicatio... A facile encryption way was successfully applied to the holographic optical encryption system with high speed,multidimensionality,and high capacity,which provided a better security solution for underwater communication.The reconstructed optical security system for information transmission was based on wavelengthλand focal length f that were keys to encryption and decryption.To finish the secure data transmission(λ,f)between sender and receiver,an extended Rivest-Shamir-Adleman(ERSA)algorithm for the encryption was achieved based on three-dimension quaternion function.Therein,the Pollard’s rho method was used for the evaluation and comparison of RSA and ERSA algorithms.The results demonstrate that the message encrypted by the ERSA algorithm has better security than that by RSA algorithm in the face of unpredictability and complexity of information transmission on the unsecure acoustic channel. 展开更多
关键词 HOLOGRAPHY QUATERNION Fourier lens extended Rivest-Shamir-Adleman(ERSA) Pollard’s rho method
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用逆推的数学思想方法解应用题 被引量:2
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作者 邓秀梅 《小学教学研究》 2013年第3期59-61,共3页
逆推的数学思想方法就是从题目的问题或结果出发,根据已知条件一步一步地进行逆向推理,逐步靠拢已知条件,直到解决问题。在小学数学应用题中,有些问题顺向思考很难理出头绪,而利用逆推的数学思想方法进行分析,就像剥笋一样一层一层深入... 逆推的数学思想方法就是从题目的问题或结果出发,根据已知条件一步一步地进行逆向推理,逐步靠拢已知条件,直到解决问题。在小学数学应用题中,有些问题顺向思考很难理出头绪,而利用逆推的数学思想方法进行分析,就像剥笋一样一层一层深入,可以使问题很容易获得解决。一、算式逆推例1:小文在计算两个数相加时,把一个加数个位上的1错误地当做7,把另一个加数十位上的8错误地当做3, 展开更多
关键词 数学思想方法 逆推 数学应用题 已知条件 逆向推理 甲乙丙 文在 邓秀梅 元里 元后
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Distribution of dissolved cadmium in Prydz Bay,Antarctica
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作者 孙维萍 扈传昱 +2 位作者 韩正兵 薛斌 潘建明 《Marine Science Bulletin》 CAS 2011年第1期50-59,共10页
In order to better understand the spatial and temporal distribution of dissolved cadmium in Prydz Bay, east Antarctica, seawaters were sampled by CTD during the CHINARE-25 cruise (Oct. 2008 - Apr. 2009) and the conc... In order to better understand the spatial and temporal distribution of dissolved cadmium in Prydz Bay, east Antarctica, seawaters were sampled by CTD during the CHINARE-25 cruise (Oct. 2008 - Apr. 2009) and the concentrations of cadmium were analyzed by AAS (Atomic Absorption Spectrometry) in the clean laboratory. Together with the data of macronutrients and chl.a from the same cruise, the relationship between cadmium and biological process was studied. The results showed that the concentrations of Cd in the surface water had a good relationship with chl.a and biologicl process was the important factor that influenced the distribution of dissolved Cd in the surface water. Linear relationship was found between dissolved Cd and phosphate in the surface water and the high ratio of Cd/P at the edge of ice shelf was most probably due to ice melting, vertical distribution of Cd was similar to those of macronutrient such as phosphate and was affected by decomposition of organic particals. The temporal change of dissolved Cd in upper layer was slight and tide probably had influence on the change. 展开更多
关键词 dissolved cadmium MICRONUTRIENT Prydz Bay ANTARCTICA
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《解决问题》导学案实录
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作者 吴雪莲 《黑河教育》 2015年第7期33-33,共1页
教学目标:1.根据除法的意义,会用除法解决此类型的实际问题。2.继续经历解决问题的全过程,会从多余的信息中选取有效信息,积累解决问题的方法和经验,提高解决问题的能力。3.感受数学知识的内在联系,培养学生发现问题、提出问题的能力... 教学目标:1.根据除法的意义,会用除法解决此类型的实际问题。2.继续经历解决问题的全过程,会从多余的信息中选取有效信息,积累解决问题的方法和经验,提高解决问题的能力。3.感受数学知识的内在联系,培养学生发现问题、提出问题的能力。教学重点:会选择有效信息,用除法解决实际问题。教学难点:建立用除法解决问题的模型,深化对除法意义的理解。 展开更多
关键词 导学 教学重点 鲤鱼跳龙门 已知条件 时用 求一 展示交流 元里 列式
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春天之桃夭夭
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作者 黄武剑 《校园心理(医学心理指导)》 2005年第2期16-17,共2页
关键词 无赖 桃花 元里 看天 同学
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故事里一直有我们的时光
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作者 林深之 《快乐阅读》 2015年第1期67-67,共1页
我们没有生活在同一个地方,却被共同的记忆捆绑在一起。那个有着"美食天堂"和"购物胜地"之称的香港生活着一头猪,永远将帽子反着戴,模样蠢萌,行为缓慢,没有腰,没有脖子,喜欢吃快快鸡,再或者记忆一转,将一连串特色... 我们没有生活在同一个地方,却被共同的记忆捆绑在一起。那个有着"美食天堂"和"购物胜地"之称的香港生活着一头猪,永远将帽子反着戴,模样蠢萌,行为缓慢,没有腰,没有脖子,喜欢吃快快鸡,再或者记忆一转,将一连串特色美食的名字稀里哗啦倒出来,二次元里的火鸡、啫啫鸡煲、叉烧饭、常餐、快餐,在三次元的我们看来也能食欲大增……麦兜系列的第五部《麦兜·我和我妈妈》终于拾回了熟悉的正港味。这一次, 展开更多
关键词 美食天堂 三次元 二次元 漫漫长夜 陈小姐 生存技能 元里 郑振铎 能将 米油
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在低年级数学教学中培养学生的练习兴趣
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作者 潘启斌 《小学教学研究》 1992年第7期27-28,共2页
练习是学生巩固知识、形成技能、发展智力的基本途径。在小学数学教学中,从低年级开始就注重学生练习兴趣的培养,不仅对学生现在的学习有利,而且对于他们以后的数学学习也将产生积极的作用,是提高小学数学教学质量的一条重要途径。那么... 练习是学生巩固知识、形成技能、发展智力的基本途径。在小学数学教学中,从低年级开始就注重学生练习兴趣的培养,不仅对学生现在的学习有利,而且对于他们以后的数学学习也将产生积极的作用,是提高小学数学教学质量的一条重要途径。那么,如何使低年级学生对数学练习产生兴趣呢?我以为有以下几种培养兴趣的方式: (一) 注重使用激励、表扬的语言在教学活动中,学生对教师的语言是非常敏感的,低年级学生则更是如此。教师粗暴、讥笑、训斥的语言常会给学生幼小的心灵造成创伤,而教师激励、表扬的语言则能成为学生学习活动的很好动力。 展开更多
关键词 数学教学 数学能力 进位加法 教学活动 练习课 小学低年级 课堂气氛 课堂练习 元里 实践证明
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Analysis of the Dynamic Response of a Shield Tunnel in Soft Soil Under a Metro-Train Vibrating Load 被引量:10
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作者 DENG Fei-huang MO Hai-hong +1 位作者 ZENG Qing-jun YANG Xiao-jie 《Journal of China University of Mining and Technology》 EI 2006年第4期509-513,共5页
This paper concerns the impact of an operating metro train on the structure of a shield tunnel lining and its soft foundation. An elastoplastic 3D dynamic finite difference model was established by using the FLAC3D nu... This paper concerns the impact of an operating metro train on the structure of a shield tunnel lining and its soft foundation. An elastoplastic 3D dynamic finite difference model was established by using the FLAC3D numerical soft- ware. By fully considering the joints, the A-B-K segments and the soft stratum, the dynamic response of the shield tunnel buried in thick, soft soil under the vibrating load induced by a metro train was numerically simulated. The simulation result, for which the joint was considered, was compared with the result when the joint was not considered. The results show that an operating metro train induces a significant dynamic response in the structure of the lining of the shield tunnel and its soft foundation. The severe dynamic response zones of the lining structure are largely distributed in the range of the lower half of the segment-ring and the nearer to the bottom of the segment-ring, the more severe the response. Of two horizontally symmetric, corresponding places on the segment lining, the one near the joint is more severe in its dynamic response than that of the one far from the joint; the nearer the zone of the foundation soil to the lower half of the seg- ment-ring, the more severe the dynamic response. The maximum shear strain of the foundation soil takes place near the joint between two normal segments at the bottom. The dynamic response influenced by joints is more severe than the response not influenced by joints, showing that the non-joint assumption is somewhat impractical. 展开更多
关键词 dynamic response train vibrating load JOINT shield tunnel SEGMENT
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A novel ring vibrating gyroscope based on side piezo-electrodes 被引量:4
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作者 周鑫 吴宇列 +2 位作者 吴学忠 张勇猛 郑煜 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第3期555-561,共7页
Solid-state wave gyroscope is one kind of high-performance vibrating gyroscopes. The present work develops a new type of solid-state wave gyroscope—a ring vibrating gyroscope driven by piezo-electrodes located on the... Solid-state wave gyroscope is one kind of high-performance vibrating gyroscopes. The present work develops a new type of solid-state wave gyroscope—a ring vibrating gyroscope driven by piezo-electrodes located on the sidewall of the structure. It has advantages of large vibrating amplitude, high energy conversion efficiency and compact structure. The working principle of the piezoelectric ring vibrating gyroscope is based on the inertia effect of the standing wave in the axisymmetric resonator caused by Coriolis force. The finite element method(FEM) analysis has been implemented to characterize the ring type resonator. The prototypal gyroscope was manufactured and has been trimmed by mechanical way. The harmonic response of the ring vibrating gyroscope has been tested. The resonating frequency of the ring type resonator is 3715.6 Hz and the frequency split of the two working modes before trimming was about 5 Hz and was reduced to sub-0.01 Hz after trimming procedure. The Q-factor of the ring type resonator was 2504. Then, the turntable experiment was implemented. The measured scale factor k is 9.24 m V/[(°)·s] and the full scale range of the gyroscope is larger than ±300(°)/s. 展开更多
关键词 solid-state wave gyroscope piezoelectric gyroscope side drive ring vibrating gyroscope
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Research on Ethnic Culture Elements of Institute English Education for Three Minority Nations by Taking Man Zhouli College of Inner Mongolia University for Example
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作者 Su Fu-xing 《International Journal of Technology Management》 2015年第7期37-39,共3页
The paper focuses on the connotation of ethnic culture elements of college English education for Three Minority Nations in Inner Mongolia and comprehensive and scientific explanation for Three Minority Nations. Corres... The paper focuses on the connotation of ethnic culture elements of college English education for Three Minority Nations in Inner Mongolia and comprehensive and scientific explanation for Three Minority Nations. Corresponding solutions were proposed from the aspects of teachers, teaching materials, curriculum and so on and feasible suggestions were put forward for nationality culture building by the English education of Three Minority Nations in Inner Mongolia on this basis. 展开更多
关键词 Three Minority Nations English Education Ethnic Culture Elements
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Concept Design of a New Deep Draft Platform
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作者 李彬彬 欧进萍 《Journal of Marine Science and Application》 2010年第3期241-249,共9页
The authors analyzed requirements for a new deepwater platform, from conceptual design to hydrodynamic analysis.The design incorporated Deep Draft Multi-Spar (DDMS) that allowed easy fabrication, reduced costs, and pr... The authors analyzed requirements for a new deepwater platform, from conceptual design to hydrodynamic analysis.The design incorporated Deep Draft Multi-Spar (DDMS) that allowed easy fabrication, reduced costs, and provided favorable motion performance.It also provided a dry tree system and other benefits.The conceptual design process included dimension estimation, general arrangements, weight estimation, weight distribution, stability analysis, etc.A high order boundary element method based on potential theory and the modified Morison equation was used to predict the hydrodynamic and viscous effects of this new concept platform.The response amplitude operators (RAOs) were acquired and compared with those of a typical Truss Spar.The response of the platform to the JONSWAP spectra of 3 different extreme ocean conditions was analyzed to evaluate the seakeeping ability of the new concept.The results revealed favorable motion performance due to all the degrees of freedom available. 展开更多
关键词 Spar potential theory Morison equation deepwater platform mooring line heave plate
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Minimum distance constrained nonnegative matrix factorization for hyperspectral data unmixing 被引量:2
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作者 于钺 SunWeidong 《High Technology Letters》 EI CAS 2012年第4期333-342,共10页
This paper considers a problem of unsupervised spectral unmixing of hyperspectral data. Based on the Linear Mixing Model ( LMM), a new method under the framework of nonnegative matrix fac- torization (NMF) is prop... This paper considers a problem of unsupervised spectral unmixing of hyperspectral data. Based on the Linear Mixing Model ( LMM), a new method under the framework of nonnegative matrix fac- torization (NMF) is proposed, namely minimum distance constrained nonnegative matrix factoriza- tion (MDC-NMF). In this paper, firstly, a new regularization term, called endmember distance (ED) is considered, which is defined as the sum of the squared Euclidean distances from each end- member to their geometric center. Compared with the simplex volume, ED has better optimization properties and is conceptually intuitive. Secondly, a projected gradient (PG) scheme is adopted, and by the virtue of ED, in this scheme the optimal step size along the feasible descent direction can be calculated easily at each iteration. Thirdly, a finite step ( no more than the number of endmem- bers) terminated algorithm is used to project a point on the canonical simplex, by which the abun- dance nonnegative constraint and abundance sum-to-one constraint can be accurately satisfied in a light amount of computation. The experimental results, based on a set of synthetic data and real da- ta, demonstrate that, in the same running time, MDC-NMF outperforms several other similar meth- ods proposed recently. 展开更多
关键词 hyperspectral data nonnegative matrix factorization (NMF) spectral unmixing convex function projected gradient (PG)
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时尚太极 静心瘦身6式
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作者 潇潇 段冉 +1 位作者 Eva 刘璐 《父母必读》 2016年第10期78-79,共2页
别以为练习太极的就一定是公园里的老头老太太,其实抵御亚健康的好办法之一就是练习中国的太极拳。这里特别推荐融合了瑜伽元素、健身操元素的时尚太极,减压又瘦身,真正让你内外兼修!
关键词 身法 太御 反复练习 太素 老健 曲肘 元里 真一 太元 外展
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元代景教人名学初探——以迁居济宁的阿力麻里景教家族为中心 被引量:6
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作者 马晓林 《北京大学学报(哲学社会科学版)》 CSSCI 北大核心 2016年第1期134-140,共7页
元代景教人名学(Anthroponymy)研究需要在汉文史料的基础上进行。以新出按檀不花家族史料为中心,结合出土叙利亚文、回鹘文材料,可以逐一考察人名的词源及形态演变。通过人名、居地、年岁、身份、职官的考察,此家族始祖岳雄(岳难之讹)... 元代景教人名学(Anthroponymy)研究需要在汉文史料的基础上进行。以新出按檀不花家族史料为中心,结合出土叙利亚文、回鹘文材料,可以逐一考察人名的词源及形态演变。通过人名、居地、年岁、身份、职官的考察,此家族始祖岳雄(岳难之讹)可勘定为赤峰出土瓷质墓碑的主人Yonan。此家族五代19个人名的还原方案,揭出9个基督教名,并对汉文文献中的讹字作出校正。结合迁徙前后的语言环境来看,这个家族虽然受到汉文化的不少影响,但其景教信仰仍然很有分量。 展开更多
关键词 蒙元史 景教 也里可温 叙利亚文 回鹘文
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“婚姻存折”存幸福
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作者 灵子 《鹃花(爱人故事)》 2008年第3期36-36,共1页
我的"婚姻存折"是出嫁那天,妈妈递到我手上的。当时,我以为会是一大笔钱,打开一看发现只有1000元。我用失望的眼神看着妈妈,妈妈却笑着说:"这是我特意为你们办理的‘婚姻存折’,以后每逢值得纪念的日子,都可以存一笔钱,... 我的"婚姻存折"是出嫁那天,妈妈递到我手上的。当时,我以为会是一大笔钱,打开一看发现只有1000元。我用失望的眼神看着妈妈,妈妈却笑着说:"这是我特意为你们办理的‘婚姻存折’,以后每逢值得纪念的日子,都可以存一笔钱,等到老的时候,里面除了钱,还有无限的幸福……" 展开更多
关键词 一元钱 对我说 我爱你 心仪已久 声地 乳腺肿瘤 次取 元里
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用身边的生活,让数学课堂教学焕发出精彩的活力
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作者 李永村 《希望月报(下)》 2007年第12期48-48,共1页
数学家华罗庚曾说:宇宙之大,粒子之微,火箭之速,化工之巧,地球之变,生物之谜,日月之繁无处不用数学。新课标指出:"数学是日常生活和进一步学习必不可少的基础和工具……"让数学走进生活,是数学问题生活化,生活问题数学化。随... 数学家华罗庚曾说:宇宙之大,粒子之微,火箭之速,化工之巧,地球之变,生物之谜,日月之繁无处不用数学。新课标指出:"数学是日常生活和进一步学习必不可少的基础和工具……"让数学走进生活,是数学问题生活化,生活问题数学化。随着新课程改革的逐步实施,我们认识到,小学数学教学要以生活体验为原型,以实践活动为载体,以自主探究为动力。因此,在教学中,我们要从现实生活入手,让学生通过参与身边的数学活动,激发他们内在的情感体验,缩短学生与学习内容之间的距离,让学生主动参与新知探究,营造和谐、愉快的学习氛围。从而发现数学问题,探求数学规律,构件数学思想。 展开更多
关键词 问题生活化 课堂教学 新课程改革 课堂知识 教育理念 新华字典 元里 教育发展 自然体 明应
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ACCURACY ANALYSIS FOR QUASI-CAREY ELEMENT 被引量:18
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作者 Dongyang SHI Xiaobin HAO 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2008年第3期456-462,共7页
In this paper, a new triangular element (Quasi-Carey element) is constructed by the idea of Specht element. It is shown that this Quasi-Carey element possesses a very special property, i.e., the consistency error is... In this paper, a new triangular element (Quasi-Carey element) is constructed by the idea of Specht element. It is shown that this Quasi-Carey element possesses a very special property, i.e., the consistency error is of order O(h^2), one order higher than its interpolation error when the exact solution belongs to H^3(Ω). However, the interpolation error and consistency error of Carey element are of order O(h). It seems that the above special property has never been seen for other triangular elements for the second order problems. 展开更多
关键词 Consistency errors nonconforming finite element Quasi-Carey element
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SUPERCONVERGENCE ANALYSIS OF A NONCONFORMING TRIANGULAR ELEMENT ON ANISOTROPIC MESHES 被引量:8
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作者 Dongyang SHI Hui LIANG Caixia WANG 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2007年第4期536-544,共9页
The class of anisotropic meshes we conceived abandons the regular assumption. Some distinct properties of Carey's element are used to deal with the superconvergence for a class of two- dimensional second-order ellipt... The class of anisotropic meshes we conceived abandons the regular assumption. Some distinct properties of Carey's element are used to deal with the superconvergence for a class of two- dimensional second-order elliptic boundary value problems on anisotropic meshes. The optimal results are obtained and numerical examples are given to confirm our theoretical analysis. 展开更多
关键词 Anisotropic meshes Carey's element NONCONFORMING superclose superconvergence.
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Clinical studies on different acupuncture time for primary dysmenorrhea 被引量:3
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作者 Xue Xiao Huang Yan +1 位作者 Liu Xin Yue Zeng-hui 《Journal of Acupuncture and Tuina Science》 CSCD 2016年第6期416-419,共4页
Objective: To seek the optimal acupuncture time for primary dysmenorrhea and provide clinical basis for optimal acupuncture treatment protocol. Methods: A total of 90 eligible cases were randomly allocated into thre... Objective: To seek the optimal acupuncture time for primary dysmenorrhea and provide clinical basis for optimal acupuncture treatment protocol. Methods: A total of 90 eligible cases were randomly allocated into three groups, 30 cases in each group. Points Guanyuan(CV 4), bilateral Zusanli(ST 36) and Sanyinjiao(SP 6) were selected for patients in all three groups, with a different treatment duration: 15 min in group A, 30 min in group B and 45 min in group C. Then the clinical efficacy in each group was evaluated by pain symptom scoring. Results: As for the pain symptom scores, there were statistically significant intra-group differences between before and after treatment in three groups(all P〈0.05); coupled with statistically significant inter-group differences between group B and the other two groups(both P〈0.05). As for clinical efficacy, there were statistical differences between group B and the other two groups(both P〈0.05), indicating that 30 min of acupuncture is the optimal duration in the treatment of dysmenorrhea. Conclusion: With the same needling manipulation, 30 min of acupuncture treatment achieves a better efficacy for primary dysmenorrhea. 展开更多
关键词 Acupuncture Therapy POINT Guanyuan(CV 4) POINT Zusanli(ST 36) POINT Sanyinjiao(SP 6) DYSMENORRHEA Needle Retaining
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Mechanism study of the transmission of moxibustion heat in human acupoint tissues 被引量:6
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作者 Ding Jia-feng Chu Xin +8 位作者 Chang Xiao-rong Li Xin-mei Zeng Yao Liang Jian Xu Xue-mei Bi Ding-yan Liu Mi Dai Guo-bin Hong Jue (Translator) 《Journal of Acupuncture and Tuina Science》 CSCD 2019年第1期24-30,共7页
Objective: To discuss the topical action characteristics of the biological transmission of moxibustion heat via temperature collection and numerical modeling. Methods: Temperature of moxibustion was measured at multip... Objective: To discuss the topical action characteristics of the biological transmission of moxibustion heat via temperature collection and numerical modeling. Methods: Temperature of moxibustion was measured at multiple points at a distance of 3 cm to obtain the moxibustion temperature field nephograms by the high-accuracy temperature measure array. Finite element analysis was used to imitate the three-dimensional dynamic distribution of temperature in acupoint tissues. Results: Through numerical analysis, the one-dimensional, two-dimensional and three-dimensional distributions of temperature in human acupoint tissues at 5 min of moxibustion were established. The result showed that moxibustion heat mainly tran smitted from the surface of the tissue to the internal, and the in flue nee of moxibusti on heat decreased with the depth of the tissue. The analysis of the nephograms of acupoint tissue temperature at 5,10, 15 and 20 min of moxibustion showed that with the in crease of the moxibusti on time, the temperature in acupoint tissues consta ntly rose, and the transmission depth of moxibustion heat also further expanded inside acupoint. Conclusion: By establishing the three-dimensional dynamic model of heat transmission inside acupoint tissues with the biological parameters of human tissues and the temperature values obtained, this study used finite element analysis software ANSYS 14.0 and discovered the rules in the transmission of heat in body tissues during moxibustion, and the features in moxibustion heat transmission (from the proximal to the distant) and heat penetration (from the surface to the intern al). This study provides theoretical and experime ntal support for the application of moxibusti on in clinical practice. 展开更多
关键词 Moxibustion Therapy Moxa Stick Moxibustion Point Zusanli (ST 36) Finite Element Analysis Temperature Thermal Conductivity Temperature Field Healthy Volunteers
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