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High Power Laser Science and Engineering 2015年第3期3卷 20-27页

作者： D.T.Michel A.K.Davis W.Armstrong r.Bahr r.epstein V.N.Goncharov M.Hohenberger I.V.Igumenshchev r.Jungquist D.D.Meyerhofer P.B.radha T.C.Sangster C.Sorce D.H.Froula Laboratory for Laser Energetics University of Rochester

Self-emission x-ray shadowgraphy provides a method to measure the ablation-front trajectory and low-mode nonuniformity of a target imploded by directly illuminating a fusion capsule with laser beams. The technique uses time-resolved images of soft x-rays(>1 ke V) emitted from the coronal plasma of the target imaged onto an x-ray framing camera to determine the position of the ablation front. Methods used to accurately measure the ablation-front radius(δ r= ±1.15 μm), image-to-image timing(δ( t)= ±2.5 ps) and absolute timing(δt= ±10 ps) are *** averaging of the images provides an average radius measurement of δ( rav)= ±0.15 μm and an error in velocity of δV / V= ±3%. This technique was applied on the Omega Laser Facility [Boehly et al., Opt. Commun. 133, 495(1997)] and the National Ignition Facility [Campbell and Hogan, Plasma Phys. Control. Fusion 41, B39(1999)].

关键词： low mode nonuiformity nuclear fusion self-emission shadowgraphy shell trajectory

用先进的超声波脉冲回波技术进行厚壁套管外的水泥评价:接近极限

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国外测井技术 2014年第1期34卷 62-66页

作者： Foianini B.Mandal r.epstein 舒中强哈里伯顿中石化中原石油工程有限公司地球物理测井公司

随着全球钻井条件更为复杂和极端,经过专业设计的井及其设备不再罕见而已成为常态。政府增加监督,强调保证井的完整性以及安全操作同样影响了资产发展。因此需要重新设计干预工具应对这些挑战。超声脉冲回波技术已成功应用于0.75英寸厚... 详细信息

随着全球钻井条件更为复杂和极端,经过专业设计的井及其设备不再罕见而已成为常态。政府增加监督,强调保证井的完整性以及安全操作同样影响了资产发展。因此需要重新设计干预工具应对这些挑战。超声脉冲回波技术已成功应用于0.75英寸厚的套管外水泥评价多年。然而,传统的超声波无法产生合适的信号电平和穿透常用的深水井完井厚套管。但先进的超声波技术可以解决这个问题。腔室测试后进行各种换能器材料和激发技术的初步研究以验证在一定范围内的水泥浆和套管尺寸的数据质量和重复率。实验室结果表明,套管外水泥阻抗可达1.2英寸厚。该新服务的应用特别适合高成本、高风险资产的区域(超深水墨西哥湾,西非以及巴西近海等),在这些区域油井完整性保证和减少干预的时间和成本极为重要。

关键词：超声波技术厚壁套管脉冲回波水泥浆评价极限专业设计安全操作

Creating large EMS populations for functional genomics and breeding in wheat

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Journal of Integrative Agriculture 2024年第2期23卷 484-493页

作者： Wenqiang Wang Xizhen Guan Yong Gan Guojun Liu Chunhao Zou Weikang Wang Jifa Zhang Huifei Zhang Qunqun Hao Fei Ni Jiajie Wu Lynn epstein Daolin Fu Spring Valley Agriscience Co. Ltd.Jinan 250300China College of Life Sciences Zaozhuang UniversityZaozhuang 277160China National Key Laboratory of Wheat Improvement College of AgronomyShandong Agricultural UniversityTai’an 271018China Department of Plant Pathology University of CaliforniaDavisCA 95616USA

Wheat germplasm is a fundamental resource for basic research,applied studies,and wheat breeding,which can be enriched normally by several paths,such as collecting natural lines,accumulating breeding lines,and introducing mutagenesis *** methane sulfonate(EMS)is an alkylating agent that can effectively introduce genetic variations in a wide variety of plant *** this study,we created a million-scale EMS population(MEP)that started with the Chinese wheat cultivars‘Luyan 128’,‘Jimai 38’,‘Jimai 44’,and‘Shannong 30’.In the M1 generation,the MEP had numerous phenotypical variations,such as>3,000 chlorophyll-deficient mutants,2,519 compact spikes,and 1,692 male sterile *** were also rare mutations,including 30 independent tillers each with double *** M1 variations of chlorophyll-deficiency and compact spikes were inheritable,appearing in the M2 or M3 *** advance the entire MEP to higher generations,we adopted a single-seed descendent(SSD)*** other seed composites of M2 were used to screen other agronomically important traits,such as the tolerance to herbicide *** MEP is available for collaborative projects,and provides a valuable toolbox for wheat genetics and breeding for sustainable agriculture.

关键词： wheat germplasm ethyl methane sulfonate genetics and breeding

Analysis and Optimization of Operational and Pollutant Attributes of Diesel Engine with CNT-Infused Orange Peel Biodiesel-Diesel Blend Fuel

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Journal of Thermal Science 2024年第2期33卷 761-778页

作者： ranjeet rAI r.r.SAHOO Mechanical Engineering Department GLA UniversityMathura281406India Mechanical Engineering Department IIT(BHU)Varanasi221005India

The current study is performed to find sustainable solutions for the future of transportation and environmental *** conventional methods and experimental design table(L16 Orthogonal Array)techniques have been employed to examine and optimize a diesel-powered engine's operational and pollutant *** L16 Orthogonal Array is obtained through Taguchi's experimental design approach using Minitab 16 *** experimental design incorporated three control variables,namely engine speed,fuel type,and engine load,each with four *** operational parameters,namely brake thermal efficiency(BTE)and brake specific fuel consumption(BSFC),as well as the emission characteristics,including hydrocarbon(HC),carbon monoxide(CO),nitrogen oxide(NO),and smoke emissions,were acquired using the L16 orthogonal array(OA) and subsequently *** utilization of methodologies such as signal-to-noise(S/N) ratio and grey analysis was employed to determine the optimal operational state of the engine to achieve maximum performance while minimizing *** engine's ideal state of operation,in terms of BTE and BSFC,was determined to be at 75% engine load,1000 r/min engine speed,and using 10^(-4)(in vol) carbon nanotube incorporated 20% orange peel biodiesel(OPB20CNT100) blended fuel(A3-B1-C4).The study indicated that engine load significantly influenced BTE and BSFC,with 84.05% and 87.79% contribution factors,*** 25% engine load,1000 r/min,and OPB20CNT100 fuel(A1-B1-C4) CO,smoke,NO,and HC emissions were the *** load affects emissions the *** BSFC increased 3.10% and NO emissions 1.77%.BTE,CO,smoke,and HC emissions decreased by 1.9%,12.29%,47.05%,and 47.22%,respectively,at optimal operating conditions concerning diesel *** study shows that Taguchi-Grey's experimental design optimizes diesel engine operational and pollutant *** outcomes revealed that orange peel biodiesel infused with CNT can replace diesel fuel in a

关键词： Taguchi-Grey method OPB20CNT100 transesterification S/N ratio GrG HC CO and NO

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全球变暖对健康有害吗?

Kinematic analysis of flexible bipedal robotic systems

新思路 2001年第1期

作者： Paul r.epstein

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 795-818页

作者： r.FAZEL A.M.SHAFEI S.r.NEKOO Department of Mechanical Engineering Shahid Bahonar University of KermanKerman ***Iran Departamento de Ingenieria de Sistemas y Automatica Escuela Técnica Superior de IngenieriaUniversidad de SevillaSeville 41092Spain

In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for numerous *** distinguishes the present research from similar works is the consideration of flexibility in the constituent links of this type of robotic *** is not a far-fetched assumption because in the transient(impact)phase,due to the impulsive forces which are applied to the system,the likelihood of exciting the vibration modes increases ***,the human leg bones that are involved in walking are supported by viscoelastic muscles and ***,for achieving more exact results,it is essential to model the robot links with viscoelastic *** this end,the Gibbs-Appell formulation and Newton's kinematic impact law are used to derive the most general form of the system's dynamic equations in the swing and transient phases of *** most important issue in the passive walking motion of bipedal robots is the determination of the initial robot configuration with which the system could accomplish a periodic and stable gait solely under the effect of gravitational *** extremely unstable nature of the system studied in this paper and the vibrations caused by the impulsive forces induced by the impact of robot feet with the inclined surface are some of the very serious challenges encountered for achieving the above-mentioned *** overcome such challenges,an innovative method that uses a combination of the linearized equations of motion in the swing phase and the algebraic motion equations in the transition phase is presented in this paper to obtain an eigenvalue *** solving this problem,the suitable initial conditions that are necessary for the passive gait of this bipedal robot on a sloping surface are *** effects of the characteristic parameters of elastic links including the modulus of elasticity and the Kelvin-Voigt coefficient on the walking stability of this type of

关键词： bipedal robot flexible link swing phase transient phase eigenvalue problem Kelvin-Voigt coefficient

Holographic dark energy in non-conserved gravity theory

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Communications in Theoretical Physics 2024年第4期76卷 126-133页

作者： H r Fazlollahi Institute of Gravitation and Cosmology Peoples Friendship University of Russia(RUDN University)6 Miklukho-Maklaya StMoscow117198Russia

recently, reconsidering the rastall idea T_(μ;νν)^(v)=α_(,μ) through relativistic thermodynamics gives a new form for the scalar field α which led us to construct modern modified theory of gravity debugged ‘non-conserved gravity theory’ Fazlollahi 2023 Euro. Phys. J. C 83 923. This theory unlike other modified theories of gravity cannot directly explain the current acceleration expansion in the absence of the cosmological constant and or existence of other forms of dark energy. Hence, in this study we have reinvestigated holographic dark energy Ρ_(X)~H^(2) in the non-conserved theory of gravity. In this context, the density and pressure of dark energy depend on the non-conserved term and density of the dust matter field. As shown, due to non-conservation effects on large-scale structures, unlike the original holographic model, our model onsets an acceleration epoch for the current Universe satisfies observations. Moreover, the interaction and viscous scenarios are studied for this model.

关键词： non-conserved gravity covariant form of thermodynamics holographic dark energy

Pile foundation in alternate layered liquefiable and non-liquefiable soil deposits subjected to earthquake loading

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 359-376页

作者： Praveen Huded M Suresh r Dash LEA Associates South East Asia Pvt.Ltd. New Delhi 110044India Indian Institute of Technology Bhubaneswar Khurda 752050India

Pile foundations are still the preferred foundation system for high-rise structures in earthquake-prone *** foundations have experienced failures in past earthquakes due to *** on pile foundations in liquefiable soils has primarily focused on the pile foundation behavior in two or three-layered soil ***,in natural occurrence,it may occur in alternative layers of liquefiable and non-liquefiable ***,the experimental and/or numerical studies on the layered effect on pile foundations have not been widely addressed in the *** of the design codes across the world do not explicitly mention the effect of sandwiched non-liquefiable soil layers on the pile *** the present study,the behavior of an end-bearing pile in layered liquefiable and non-liquefiable soil deposit is studied *** study found that the kinematic bending moment is higher and governs the design when the effect of the sandwiched non-liquefied layer is considered in the analysis as opposed to when its effect is ***,ignoring the effect of the sandwiched non-liquefied layer in a liquefiable soil deposit might be a nonconservative design approach.

关键词： pile foundation liquefaction alternately layered soil fixity effect layered effect

Conservation laws,Lie symmetries,self adjointness,and soliton solutions for the Selkov–Schnakenberg system

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Communications in Theoretical Physics 2024年第2期76卷 29-44页

作者： Kashif Ali Aly r Seadawy Syed T r rizvi Noor Aziz Department of Mathematics COMSATS University IslamabadLahore CampusPakistan Mathematics Department Faculty of ScienceTaibah UniversityAl-Madinah Al-Munawarah41411Saudi Arabia

In this article,we explore the famous Selkov–Schnakenberg(SS)system of coupled nonlinear partial differential equations(PDEs)for Lie symmetry analysis,self-adjointness,and conservation ***,miscellaneous soliton solutions like dark,bright,periodic,rational,Jacobian elliptic function,Weierstrass elliptic function,and hyperbolic solutions of the SS system will be achieved by a well-known technique called sub-ordinary differential *** these results are displayed graphically by 3D,2D,and contour plots.

关键词： Selkov-Schnakenberg system Lie symmetry analysis conservation laws adjointness integrability

FEA-based Geometrical Modification of Switched reluctance Motor for radial Force reduction

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Chinese Journal of Electrical Engineering 2024年第1期10卷 124-135页

作者： rani S Jayapragash r School of Electrical Engineering Vellore Institute of TechnologyChennai 600127India

Switched reluctance motors(SrMs)are becoming increasingly popular in the automotive sector owing to their robust ***,SrMs are preferred particularly for EV applications owing to their fault tolerance,magnet-free structure,and high power/torque *** main concerns of SrM compared to other machines include torque ripple and *** primary cause of vibration is the radial force created by the SrM.A geometry-based modification of the SrM to reduce the radial force without significantly changing the average torque produced is *** primary goal is to design a 4-phase,8/6 SrM with a lower radial *** possible geometrical alterations are proposed:one with square windows and the other with circular holes on the rotor *** windows are sized and positioned to avoid flux *** criteria are developed for the optimal window size and *** element analysis(FEA)modelling of the SrM is used to validate its *** FEA results are compared with the performance parameters obtained using the analytical *** the multiphysics design tool ANSYS to obtain the natural frequencies and associated deformations through modal *** to the conventional geometry,the radial force is significantly reduced by providing windows.

关键词： 8/6 SrM radial force modal analysis FEA analysis natural frequencies SrM with windows