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A Chaotic Pulse Train Generator Based on Henon Map

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Intelligent Automation & Soft Computing 2023年第7期37卷 1197-1207页

作者： Babu H.Soumya n.Vijayakumar K.Gopakumar College of Engineering Trivandrum695016India Government Engineering College Barton HillTrivandrum695035India APJ Abdul Kalam Technological University Trivandrum695016India

The Henon map forms one of the most-studied two-dimensional discrete-time dynamical systems that exhibits chaotic *** Henon map takes a point(Xn,Yn)in the plane and maps it to a new point(Xn+1,Yn+1).In this paper,a chaotic pulse generator based on the chaotic Henon map is *** consists of a Henon map function subcircuit to realize the Henon map and another subcircuit to perform the iterative *** Henon map subcircuit comprises operational amplifiers,multipliers,delay elements and resistors,whereas,the iterative subcircuit is implemented with a simple design that comprises of an edge forming circuit followed by a monostable multivibrator and a voltage controlled switch without the use of any clock *** proposed design can be used to realize the Henon map and also to generate a chaotic pulse train,with a controllable time interval and pulse *** proposed circuit is implemented and simulated using Multisim 13.0 and MATLAB *** chaotic nature of the generated pulse train and also the time interval between the consecutive pulses is verified by the calculation of its Lyapunov exponents.

关键词： Chaos iterated maps henon map chaotic pulse train lyapunov exponents

岩石、节理以及岩体抗剪强度的相关问题与解决方法

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地壳构造与地壳应力 2014年第2期 1-28页

作者： n.R. barton 江英豪 nick barton &Associates

岩石、节理以及岩体抗剪强度这三个重要的论题,每个论题即使是概括性的讨论,也都值得使用单独的论卷来深入讨论,但本文仅在一篇文章中将它们联系起来进行总结。包罗万象的岩体剪切强度既不能用Hoek-Brown准则中的高级代数来表述,也无法... 详细信息

岩石、节理以及岩体抗剪强度这三个重要的论题,每个论题即使是概括性的讨论,也都值得使用单独的论卷来深入讨论,但本文仅在一篇文章中将它们联系起来进行总结。包罗万象的岩体剪切强度既不能用Hoek-Brown准则中的高级代数来表述,也无法用摩尔-库仑的线性准则来定义,因为这些方法都是预先估计,而不是建立在经验上的后续检验。完整岩体的高度非线性的剪切强度是小应变破坏时的重要组成部分,其定义严重偏离了摩尔库伦准则所定义的曲线,而且曲率也比Hoek-Brown准则所定义的曲线大。在地壳岩石的深处或许是塑性的,或者处于它们的临界状态。这些不同的脆弱的节理和裂缝,给土木和采矿工程的稳定性方面制造了诸多难题,但是它们也是帮助裂隙化储层维持渗透性的重要因素。节理具备高度各向异性的特点。节理裂隙在高法向刚度和低尺度的剪切刚度条件下呈现出的属性特征差异非常大。正如1966年穆勒在书中所述,与完整的岩体相比,节理能够在更大的剪切应变下明显地达到最大剪切强度,而且在内聚力消失后,仍然保持它们的摩擦力。在非线性Hoek-Brown表达式中和内聚力c加上?tan的条件下,增加完整岩体的内聚力以及节理的剪切阻力是错误的。在更大的剪切应变下存在第三个剪切强度分量,在粘土填充的(比如在断层附近的区域)的不连续区域存在更小的摩擦力强度。最后,这里存在某一平面上的从主应力、到正应力再到剪切应力的应力转换大问题。侧向膨胀、剪切破坏以及该平面的存在都违背了原始的理论假设。

关键词：节理裂隙完整岩体抗剪强度地壳岩石剪切强度 Brown 剪切应变不连续区域

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没有地理隔离的物种形成

地质科学译丛 1989年第4期6卷 38-39页

作者： n.H.barton 杨铁汾

物种起源主要地不是达尔文认为的那种物种起源,即物种形成仅仅是现存谱系内形态演化的延伸。现在,种被看作是遗传学上独立的单位,但当必须涉及到一些不适合个体的出现时,因这些个体几乎不可能与其它种交换基因,种的起源是很难理解的。... 详细信息

物种起源主要地不是达尔文认为的那种物种起源,即物种形成仅仅是现存谱系内形态演化的延伸。现在,种被看作是遗传学上独立的单位,但当必须涉及到一些不适合个体的出现时,因这些个体几乎不可能与其它种交换基因,种的起源是很难理解的。大多数进化生物学家相信,只要有一个地理障碍,阻隔祖先与后裔之间的基因交换,新种就能够演化形成,这就是物种形成的异域性。由于基因流和以杂种为背景的选择将压倒任何生殖隔离的趋势,那么一新种出现在祖先的同一地区或邻近的种群中,通常是不可能的。相反,种群遗传学理论表明,在一定的自然选择和种群结构的条件下,存在交配障碍,物种能够不管基因流而进化。

关键词：地理物种地史学古生物学

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进化

作者： (英)n. H. 巴顿(nicholas H. barton)[等]

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绵羊白肝病

郑州牧业工程高等专科学校学报 1983年第S1期 40-41页

作者：王建民 n.J.barton 澳

绵羊白肝病1967年发现于新西兰,现该病在新西兰每年春季和夏季流行。患此病者多为羔羊。病畜症状为:食欲骤减,体重减轻,有时出现黄疸和感光过敏现象。

关键词：白肝病澳大利亚新西兰大洋洲绵羊羔羊

Pituitary Lesions, Obesity, and Mesenteric Lipomas in Insulin-Resistant Horses

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Open Journal of Veterinary Medicine 2014年第9期4卷 190-196页

作者： Kimberly M. newkirk Kelly A. Chameroy Elizabeth M. Tadros barton W. Rohrbach nicholas Frank Department of Biomedical and Diagnostic Sciences College of Veterinary Medicine University of Tennessee Knoxville TN USA Department of Large Animal Clinical Sciences College of Veterinary Medicine University of Tennessee Knoxville TN USA

The aim of the current study was to identify associations between pituitary lesions, body condition scores, and mesenteric lipomas in horses with insulin resistance. necropsy examinations were performed following euthanasia in 30 adult horses designated as insulin resistant (n = 11) or insulin sensitive (n = 19). Insulin sensitivity was determined using the insulin-modified frequently sampled intravenous glucose tolerance test and resting insulin concentrations. At necropsy, mesenteric lipomas were measured. The pituitary and adrenal glands, pancreas, and liver were evaluated histologically;pituitary glands were scored based on published criteria. Insulin-resistant horses had significantly higher pituitary scores (p = 0.0035) and body condition scores (p = 0.0001), even when adjusting for age, and a greater frequency of mesenteric lipomas (p = 0.014) and greater lipoma area (p = 0.0332) than insulin-sensitive horses. Regardless of insulin status, horses with pituitary scores ≥3 (diffuse hyperplasia;n = 25) had higher body condition scores (p = 0.0313) and a greater frequency of mesenteric lipomas (p n those with lower pituitary scores. High body condition score was not correlated to an increased frequency of mesenteric lipomas. Detection of higher pituitary scores in insulin-resistant horses suggested an association between insulin resistance and pituitary morphology. Horses in the insulin-resistant group and those with high pituitary scores had higher body condition scores and a greater frequency of mesenteric lipomas. These horses might be at increased risk for lipoma-associated colic.

关键词： Body Condition Score Horse Insulin Resistance Mesenteric Lipoma Pituitary

Surface Perfluoroalkyl Chains Segregation: A Tool for Reducing Calcium Deposits in Medical Grade Poly(Methyl Methacrylate)

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Journal of Biomaterials and nanobiotechnology 2017年第2期8卷 176-187页

作者： Baljit K. Ghatora Peter J. S. Foot Stephen J. barton Ravtej S. Thatti Antonio Papagni Luca Vaghi Materials Research Centre SEC Faculty Kingston University Surrey UK Department of Materials Science University of Milano-Bicocca Milano Italy

Intraocular lenses can be manufactured from a wide variety of polymers, but due to the lost cost associated with the use of Poly (methyl methacrylate) (PMMA), it is still the preferred material used in the developing countries. However, a major drawback to its use is the build-up of calcium containing deposits that are formed on the intraocular lens over a period of time. In an attempt to hinder this deposition, surface modification of medical grade PMMA has been carried out using perfluoroalkyl chain (1,2,4-trifluoro-3-(C10F21CH2O)-7-(n,n)-dimethylaminoacridine) segregation. The segregation was explored using a 1% 1,2,4-trifluoro-3-(C10F21CH2O)-7-(n,n)-dimethyla-minoacridine in two methods: film casting and spin-coating, a thin film onto preformed PMMA discs. Both methods were compared against control PMMA to determine which method provided the best hindrance against calcium containing deposits when immersed in a simulated aqueous humour solution. Characterisation of the surface using scanning electron microscopy coupled with energy;dispersive x-ray analysis indicated that the surface segregation of perfluoroalkyl chains had hindered calcification in both methods. This pleminary research shows promising results of employing perfluoroalkyl chains in the surface segregation of biomaterials that can be employed in intraocular lenses.

关键词： Poly(Methyl Methacrylate) (PMMA) Perfluoroalkyl Segregation Medical Polymers Wettability Calcium Deposits

Performance and calibration of quark/gluon-jet taggers using 140 fb^(-1) of pp collisions at √s=13 TeV with the ATLAS detector

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Chinese Physics C 2024年第2期48卷 1-25页

作者： G. Aad B. Abbott K. Abeling n.J. Abicht S.H. Abidi A. Aboulhorma H. Abramowicz H. Abreu Y. Abulaiti B.S. Acharya C. Adam Bourdarios L. Adamczyk S.V. Addepalli M.J. Addison J. Adelman A. Adiguzel T. Adye A.A. Affolder Y. Afik M.n. Agaras J. Agarwala A. Aggarwal C. Agheorghiesei A. Ahmad F. Ahmadov W.S. Ahmed S. Ahuja X. Ai G. Aielli A. Aikot M. Ait Tamlihat B. Aitbenchikh I. Aizenberg M. Akbiyik T.P.A. Åkesson A.V. Akimov D. Akiyama n.n. Akolkar K. Al Khoury G.L. Alberghi J. Albert P. Albicocco G.L. Albouy S. Alderweireldt M. Aleksa I.n. Aleksandrov C. Alexa T. Alexopoulos F. Alfonsi M. Algren M. Alhroob B. Ali H.M.J. Ali S. Ali S.W. Alibocus M. Aliev G. Alimonti W. Alkakhi C. Allaire B.M.M. Allbrooke J.F. Allen C.A. Allendes Flores P.P. Allport A. Aloisio F. Alonso C. Alpigiani M. Alvarez Estevez A. Alvarez Fernandez M. Alves Cardoso M.G. Alviggi M. Aly Y. Amaral Coutinho A. Ambler C. Amelung M. Amerl C.G. Ames D. Amidei S.P. Amor Dos Santos K.R. Amos V. Ananiev C. Anastopoulos T. Andeen J.K. Anders S.Y. Andrean A. Andreazza S. Angelidakis A. Angerami A.V. Anisenkov A. Annovi C. Antel M.T. Anthony E. Antipov M. Antonelli F. Anulli M. Aoki T. Aoki J.A. Aparisi Pozo M.A. Aparo L. Aperio Bella C. Appelt A. Apyan n. Aranzabal S.J. Arbiol Val C. Arcangeletti A.T.H. Arce E. Arena J-F. Arguin S. Argyropoulos J.-H. Arling O. Arnaez H. Arnold G. Artoni H. Asada K. Asai S. Asai n.A. Asbah J. Assahsah K. Assamagan R. Astalos S. Atashi R.J. Atkin M. Atkinson H. Atmani P.A. Atmasiddha K. Augsten S. Auricchio A.D. Auriol V.A. Austrup G. Avolio K. Axiotis G. Azuelos D. Babal H. Bachacou K. Bachas A. Bachiu F. Backman A. Badea P. Bagnaia M. Bahmani A.J. Bailey V.R. Bailey J.T. Baines L. Baines O.K. Baker E. Bakos D. Bakshi Gupta V. Balakrishnan R. Balasubramanian E.M. Baldin P. Balek E. Ballabene F. Balli L.M. Baltes W.K. Balunas J. Balz E. Banas M. Bandieramonte A. Bandyopadhyay S. Bansal L. Barak M. Barakat E.L. Barberio D. Barberis M. Barbero M.Z. Barel K.n. Barends T. Barillari M-S. Barisits T. Barklow P. Baron D.A. Baron Mo The ATLAS Collaboration

The identification of jets originating from quarks and gluons,often referred to as quark/gluon tagging,plays an important role in various analyses performed at the Large Hadron Collider,as Standard Model measurements and searches for new particles decaying to quarks often rely on suppressing a large gluon-induced *** paper describes the measurement of the efficiencies of quark/gluon taggers developed within the ATLAS Collaboration,using √s=13 TeV proton–proton collision data with an integrated luminosity of 140 fb^(-1) collected by the ATLAS *** taggers with high performances in rejecting jets from gluon over jets from quarks are studied:one tagger is based on requirements on the number of inner-detector tracks associated with the jet,and the other combines several jet substructure observables using a boosted decision tree.A method is established to determine the quark/gluon fraction in data,by using quark/gluon-enriched subsamples defined by the jet *** in tagging efficiency between data and simulation are provided for jets with transverse momentum between 500 GeV and 2 TeV and for multiple tagger working points.

关键词： ATLAS JET QUARK GLUOn TAGGInG

前颞叶切除术的视野缺损:Meyer环的定量再评估

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世界核心医学期刊文摘（神经病学分册） 2005年第12期1卷 24-25页

作者： barton J.J.S. Hefter R. 方伯言 neuro-Ophthalmology Section D VGH Eye Care Center 2550 Willow Street Vancouver BC V5Z 3N9 Canada

Temporal lobectomy is often complicated by superior quadrantanopia. The relation of field loss to sagittal resection length can inform us about the functional anatomy of Meyer’s loop, with ramifications for surgical planning. However, the literature has produced highly variable results. We studied 29 patients with anterior temporal lobectomies using Goldmann perimetry. 24 patients had post-operating neuroimaging, with which we assessed resection length relative to each patient’s temporooccipital dimensions. For the field defect we calculated the proportion of area lost for three isopters. We found a significant correlation between resection size and field loss for both nasal and temporal defects. Linear regressions suggested an anterior limit of Meyer’s loop at 24 to 28 mm from the anterior temporal pole, and involvement of the lower quadrant when resections reached 70 to 79 mm, with significant inter-subject variability. The nasal defect was 15%greater than the temporal defect for all degrees of quadrantanopia, with no difference between right and left hemispheres. Macular involvement began when field defects reached 61%of quadrant area, corresponding to a resection of about 58 mm. Patterns of field loss showed that the lower margins were most often horizontal or with a slight slope towards fixation, rather than true wedge defects. We conclude that field loss is related to resection length and that Meyer’s loop extends more anteriorly than estimated in traditional surgical studies, in agreement with modern MRI and dissection studies. The patterns of field loss support a revised retinotopic model in which the most anterior fibers of Meyer’s loop represent the superior field, not the vertical meridian as traditionally proposed.

关键词：前颞叶切除术 Meyer 视野缺损颞极视野检查象限盲术后神经手术计划功能解剖力线

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