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Hyper Gravity-Induced Transients in <i>Phycomyces</i>as Measured by Single Beam Spectrophotometer on the Sounding Rocket TEXUS 50
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作者 Werner Schmidt 《Journal of Modern Physics》 2018年第2期273-286,共14页
In the first paper of two referring to the TEXUS 50 campaign using micro dual wavelength spectrometers (MDWS) we kinetically determined the threshold1 for GIACs (gravity-induced absorption changes) in Phycomyces to be... In the first paper of two referring to the TEXUS 50 campaign using micro dual wavelength spectrometers (MDWS) we kinetically determined the threshold1 for GIACs (gravity-induced absorption changes) in Phycomyces to be lower than 25 × 10&minus;3 g (http://file.scirp.org/pdf/JMP_2015082810060783.pdf). In this second paper, we attended measurement of GIAC-spectra. Unexpectedly, during the upwards movement, i.e. the hypergravity phase up to top acceleration values reaching 11.6 g at 35.4 s after liftoff we observed transient GIAC-spectra ranging from 380 to 750 nm. In addition, during the whole acceleration phase of 68.2 s, another component near 700 nm develops which remains stable during the whole “free fall trajectory parabola” for 381.3 s. The subsequent reentry of the rocket leads to extraordinary deceleration values up 37.8 g, completely destroying Phycomyces sporangiophores excluding their spectral measurement. During the microgravity phase and by centrifuge operation we were unable to detect any GIAC-spectra (in contrast to kinetic MDWS-measurements, first paper). 展开更多
关键词 MDWS (Micro-Dual Wavelength Spectrophotometer) Single beam SPECTROPHOTOMETER (SBS) Diode Array Spectrometer (USB-2000%PLUS% Ocean Optics) GIAC (Gravity-Induced Absorption Change) PHYCOMYCES blakesleeanus Sporangiophore Micro- and Hypergravity Texus 50 Sounding Rocket Graviperception. HYPER Gravity-Induced Transients
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Enhancement of proton collimation and acceleration by an ultra-intense laser interacting with a cone target followed by a beam collimator
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作者 Yajuan HOU Li WANG +1 位作者 Haibo SANG Baisong XIE 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第4期76-84,共9页
A special method is proposed of a laser-induced cavity pressure acceleration scheme for collimating,accelerating and guiding protons,using a single-cone target with a beam collimator through a target normal sheath acc... A special method is proposed of a laser-induced cavity pressure acceleration scheme for collimating,accelerating and guiding protons,using a single-cone target with a beam collimator through a target normal sheath acceleration mechanism.In addition,the problems involved are studied by using two-dimensional particle-in-cell simulations.The results show that the proton beam can be collimated,accelerated and guided effectively through this type of target.Theoretically,a formula is derived for the combined electric field of accelerating protons.Compared with a proton beam without a beam collimator,the proton beam density and cut-off energy of protons in the type II are increased by 3.3 times and 10%respectively.Detailed analysis shows that the enhancement is mainly due to the compact and strong sheath electrostatic field,and that the beam collimator plays a role in focusing energy.In addition,the simulation results show that the divergence angle of the proton beam in type II is less than 1.67 times that of type I.The more prominent point is that the proton number of type II is 2.2 times higher than that of type I.This kind of target has important applications in many fields,such as fast ion ignition in inertial fusion,high energy physics and proton therapy. 展开更多
关键词 single-cone TARGET with beam COLLIMATOR TARGET normal SHEATH ACCELERATION mechanism(TNSAM) particle-in-cell(PIC) SHEATH static electric field(SSEF) inertial fusion high energy physics and PROTON therapy PROTON beam density cut-off energy of PROTON
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MAG动员/BEAM预处理治疗恶性淋巴瘤的长期随访
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作者 刘跃均 吴德沛 +9 位作者 孙爱宁 仇惠英 金正明 苗瞄 唐晓文 傅 马骁 赵晔 夏学鸣 林宝爵 《江苏医药》 CAS CSCD 北大核心 2005年第4期244-246,共3页
目的探讨恶性淋巴瘤(ML)用MAG方案动员、BEAM方案预处理、自体外周血干细胞移植(APBSCT)的疗效和毒性.方法 8年采用APBSCT治疗ML14例[9例非霍奇金淋巴瘤(NHL),5例霍奇金病(HD)],外周血干细胞动员采用MAG方案(Ara-C 2g/m2 q12 h,d1~2,MT... 目的探讨恶性淋巴瘤(ML)用MAG方案动员、BEAM方案预处理、自体外周血干细胞移植(APBSCT)的疗效和毒性.方法 8年采用APBSCT治疗ML14例[9例非霍奇金淋巴瘤(NHL),5例霍奇金病(HD)],外周血干细胞动员采用MAG方案(Ara-C 2g/m2 q12 h,d1~2,MTZ 10 mg·m2d2~3,rhG-CSF 300 μg/d),为预处理采用BEAM方案(BCNU 250 mg/m2d1,VP-16 200 mg2d2~5,Ara-C 400 mg/m-2d2~5,Mel 140 mg/m2d6).化疗结束后36~48 h回输自体造血干细胞.结果 13/14例一次采集即获足量干/祖细胞.回输单个核细胞(MNC)3.91(1.21~6.61)×108/kg、粒-单核系祖细胞(CFU-GM) 4.40(2.33~6.47)×105/kg和CD34+细胞17.79(4.79~30.69)×106/kg.所有患者移植后均获造血重建,中性粒细胞(ANC)≥0.5×109/L时间为10(8~13) d,血小板(Plt)≥20×109/L为13(9~22) d.中位随访时间46(4~100)个月,12例存活,总生存率85.7%,无病生存率78.5%.结论 MAG方案动员/BEAM方案预处理APBSCT治疗ML安全有效. 展开更多
关键词 beam MAG 访 CD34^%PLUS% CT APBS / AM
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Effect of Laser Beam Welding Parameters on Microstructure and Properties of Duplex Stainless Steel 被引量:1
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作者 Abdel-Monem El-Batahgy Abdel-Fattah Khourshid Thoria Sharef 《Materials Sciences and Applications》 2011年第10期1443-1451,共9页
The present study is concerned with laser beam welding and its effect on size and microstructure of fusion zone then, on mechanical and corrosion properties of duplex stainless steel welded joints. In this regard, inf... The present study is concerned with laser beam welding and its effect on size and microstructure of fusion zone then, on mechanical and corrosion properties of duplex stainless steel welded joints. In this regard, influence of different laser welding parameters was clarified. Both bead-on-plate and autogenously butt welded joints were made using carbon dioxide laser with a maximum output of 9 kW in the continuous wave mode. Welded joints were subjected to visual, dye penetrant and radiography tests before sectioning it for different destructive tests. Accelerated corrosion test was carried out based on tafel plot technique. The results achieved in this investigation disclosed that welding parameters play an important role in obtaining satisfactory properties of welded joint. High laser power and/or high welding speed together with adjusting laser focused spot at specimen surface have produced welded joints with a remarkable decrease in fusion zone size and an acceptable weld profile with higher weld depth/width ratio. Besides, acceptable mechanical and corrosion properties were obtained. Using nitrogen as a shielding gas has resulted in improving mechanical and corrosion properties of welded joints in comparison with argon shielding. This is related to maintaining proper ferrite/austenite balance in both weld metal and HAZ in case of nitrogen shielding. As a conclusion, laser power, welding speed, defocusing distance and type of shielding gas combination have to be optimized for obtaining welded joints with acceptable profile as well as mechanical and corrosion properties. 展开更多
关键词 DUPLEX STAINLESS Steel LASER beam WELDING LASER Power WELDING Speed DEFOCUSING Distance Shielding Gas Type Fusion Zone Microstructure Mechanical Properties Corrosion Resistance
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饮酒与脑血管危险因素-脂类代谢的关系及其对BEAM的影响
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作者 宋凤英 曹升奇 《菏泽医学专科学校学报》 1998年第2期1-2,共2页
选择100例男性慢性嗜酒者,系统跟踪观察血脂蛋白、ApoA1、ApoB及脑电地形图(BEAM)等12项指标的变化,按每日饮酒量分小量、中量、大量三组与对照组比较,单因素方差分析,多组间比较及配对资料分析.中、大量饮酒(150~1500ml/d以... 选择100例男性慢性嗜酒者,系统跟踪观察血脂蛋白、ApoA1、ApoB及脑电地形图(BEAM)等12项指标的变化,按每日饮酒量分小量、中量、大量三组与对照组比较,单因素方差分析,多组间比较及配对资料分析.中、大量饮酒(150~1500ml/d以上)血清TC、TG、LDL-ch、ApoB水平升高(P<0.01),HDL-ch、ApoA1水平降低(P<0.01).BEAM异常(P<0.01);小量饮酒(100ml/d以下)血清HDL-C、ApoA水平增高(P<0.05),TC、TG、LDL-ch、ApoB略高,无统计学意义,BEAM无不良影响(P<0.05)。提出科学饮酒方法(每日<100ml低度白酒)。科学饮酒可预防脑血管病(CVD)发生,中、大量饮酒是CVD的重要危险因素。 展开更多
关键词 beam (CVD) ApoA1 LDL-ch APOB HDL-CH LDL-ch 0.05 HDL-C TC
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Estimation of the Temperature in the Weld Penetration Channel in Electron Beam Welding
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作者 D. N. Trushnikov E. S. Salomatova V. Ya. Belenkiy 《Journal of Power and Energy Engineering》 2013年第7期51-53,共3页
In this paper, the method of experimental estimation of the temperature in a penetration channel in electron beam welding is described on the basis of chemical elements concentration in the vapors above welding zone. ... In this paper, the method of experimental estimation of the temperature in a penetration channel in electron beam welding is described on the basis of chemical elements concentration in the vapors above welding zone. The temperature of a vapor-gas phase in the penetration channel is determined when equating calculated and experimental concentrations of the elements. 展开更多
关键词 Electron beam WELDING The Chemical Composition of the WELD Austenitny STAINLESS Steel THERMODYNAMIC CALCULATIONS Steam Pressure in the CHANNEL
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The Effects of the Longitudinal Axis of Loading upon Bending, Shear and Torsion of a Thin-Walled Cantilever Channel Beam
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作者 David W. A. Rees Abdelraouf M. Sami Alsheikh 《World Journal of Mechanics》 2024年第5期73-96,共24页
Three aluminium channel sections of US standard extruded dimension are mounted as cantilevers with x-axis symmetry. The flexural bending and shear that arise with applied axial torsion are each considered theoreticall... Three aluminium channel sections of US standard extruded dimension are mounted as cantilevers with x-axis symmetry. The flexural bending and shear that arise with applied axial torsion are each considered theoretically and numerically in terms of two longitudinal axes of loading not coincident with the shear centre. In particular, the warping displacements, stiffness and stress distributions are calculated for torsion applied to longitudinal axes passing through the section’s centroid and its web centre. The stress conversions derived from each action are superimposed to reveal a net sectional stress distribution. Therein, the influence of the axis position upon the net axial and shear stress distributions is established compared to previous results for each beam when loading is referred to a flexural axis through the shear centre. Within the net stress analysis is, it is shown how the constraint to free warping presented by the end fixing modifies the axial stress. The latter can be identified with the action of a ‘bimoment’ upon each thin-walled section. 展开更多
关键词 Thin-Aluminium Channels Cantilever beam Bending Shear Torsion WARPING BIMOMENT Flexural Axis Centre of Twist CENTROID Shear Centre Torsional Stiffness Constrained Stress
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Image Reconstruction from Fan-Beam Projections without Back-Projection Weight in a 2-D Dynamic CT: Compensation of Time-Dependent Rotational, Uniform Scaling and Translational Deformations 被引量:1
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作者 A. V. Narasimhadhan Aman Sharma Dipen Mistry 《Open Journal of Medical Imaging》 2013年第4期136-143,共8页
In a dynamic CT, the acquired projections are corrupted due to strong dynamic nature of the object, for example: lungs, heart etc. In this paper, we present fan-beam reconstruction algorithm without position-dependent... In a dynamic CT, the acquired projections are corrupted due to strong dynamic nature of the object, for example: lungs, heart etc. In this paper, we present fan-beam reconstruction algorithm without position-dependent backprojection weight which compensates for the time-dependent translational, uniform scaling and rotational deformations occurring in the object of interest during the data acquisition process. We shall also compare the computational cost of the proposed reconstruction algorithm with the existing one which has position-dependent weight. To accomplish the objective listed above, we first formulate admissibility conditions on deformations that is required to exactly reconstruct the object from acquired sequential deformed projections and then derive the reconstruction algorithm to compensate the above listed deformations satisfying the admissibility conditions. For this, 2-D time-dependent deformation model is incorporated in the fan-beam FBP reconstruction algorithm with no backprojection weight, assuming the motion parameters being known. Finally the proposed reconstruction algorithm is evaluated with the motion corrupted projection data simulated on the computer. 展开更多
关键词 Fan-beam Reconstruction Algorithm Hilbert Filter Virtual Acquisition Geometry Equiangular Detector Geometry ROTATIONAL UNIFORM SCALING and Translational Deformation Position Dependent BACK-PROJECTION Weight
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An R(x)-orthonormal theory for the vibration performance of a non-smooth symmetric composite beam with complex interface 被引量:2
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作者 Chein-Shan Liu Bo-Tong Li 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2019年第1期228-241,I0007,共15页
A composite beam is symmetric if both the material property and support are symmetric with respect to the middle point. In order to study the free vibration performance of the symmetric composite beams with different ... A composite beam is symmetric if both the material property and support are symmetric with respect to the middle point. In order to study the free vibration performance of the symmetric composite beams with different complex nonsmooth/discontinuous interfaces, we develop an R(x)-orthonormal theory, where R(x) is an integrable flexural rigidity function. The R(x)-orthonormal bases in the linear space of boundary functions are constructed, of which the second-order derivatives of the boundary functions are asked to be orthonormal with respect to the weight function R(x). When the vibration modes of the symmetric composite beam are expressed in terms of the R(x)-orthonormal bases we can derive an eigenvalue problem endowed with a special structure of the coefficient matrix A :=[aij ],aij= 0 if i + j is odd. Based on the special structure we can prove two new theorems, which indicate that the characteristic equation of A can be decomposed into the product of the characteristic equations of two sub-matrices with dimensions half lower. Hence, we can sequentially solve the natural frequencies in closed-form owing to the specialty of A. We use this powerful new theory to analyze the free vibration performance and the vibration modes of symmetric composite beams with three different interfaces. 展开更多
关键词 SYMMETRIC composite beams R(x)-orthogonality of second-order derivatives of boundary functions R(x)-orthonormal THEORY Non-smooth/discontinuous interface Sequentially closed-from natural frequencies
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Experimental Study on Seismic Behavior ofSeismic-damaged Lateral Joints in CompositeFrame Consisting of CFSST Columns and SteelBeams Strengthened with Enclosed ReinforcedConcrete
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《建筑工程(中英文版)》 2015年第2期22-29,共8页
A new composite strengthening method of seismic-damaged lateral joints in composite frame consisting of Concrete-Filled SquareSteel Tubes (CFSST) columns and steel beams strengthened with enclosed Reinforced Concre... A new composite strengthening method of seismic-damaged lateral joints in composite frame consisting of Concrete-Filled SquareSteel Tubes (CFSST) columns and steel beams strengthened with enclosed Reinforced Concrete (RC) at the ends of columns andwelding steel plates at the ends of beams was presented. Based on the current design specifications, one half scaled models of 4lateral joints in composite frame consisting of CFSST columns and steel beams were designed and manufactured. One model wasoriginal control specimen, one was strengthened by enclosed RC, and the others were strengthened after pre-damage. The destructiontests under lateral cyclic load on the models were carried. The effectiveness of seismic-damaged joints strengthened with enclosedRC and the reinforcement effect on different levels of seismic damage were studied. The test results show that seismic- damagedjoints in composite frame consisting of CFSST columns and steel beams strengthened with enclosed RC meets the strongcolumn-weak beam joints requirement of seismic design, and the failure modes are of all joints are the bending failure of steel beam.The reinforcement with enclosed RC has a significant on increasing the ultimate capacity and the seismic behaviors of joints. Thestudy indicated the rehabilitated joints recover the level of their original seismic performances before seismic damage in a certainextent damage level. Based on the test data, namely the ultimate capacity, limit displacement, ductility, the energy consumptioncoefficient, limit displacementthe strengthening method of seismic-damaged joints by strengthened with enclosed RC is an effectivemethod for seismic strengthening. 展开更多
关键词 Frame Joint with Concrete-Filled Square STEEL Tube (CFSST)-Steel beam Strengthening with Enclosed ReinforcedConcrete (RC) QUASI-STATIC Test SEISMIC Damage SEISMIC Behavior
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强流脉冲碳离子束强化T5K10刀具机理研究 被引量:4
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作者 张健 张罡 +2 位作者 毕鉴智 李玉海 姚俊 《腐蚀科学与防护技术》 CAS CSCD 北大核心 2005年第3期165-168,共4页
采用TIA-450自绝缘二极管碳离子加速器对T5K10刀具进行了强流脉冲离子束辐照表面处理,加速器的加速电压为250keV,束流密度为60A/cm2~150A/cm2,脉冲时间为80纳秒,脉冲次数为2次.XRD、SEM、EDS以及显微硬度分析研究结果表明:当束流密度达... 采用TIA-450自绝缘二极管碳离子加速器对T5K10刀具进行了强流脉冲离子束辐照表面处理,加速器的加速电压为250keV,束流密度为60A/cm2~150A/cm2,脉冲时间为80纳秒,脉冲次数为2次.XRD、SEM、EDS以及显微硬度分析研究结果表明:当束流密度达到100A/cm2,材料表面为完全熔化凝固组织;当束流密度达到150A/cm2时,表面层下也出现熔化凝固组织;熔化凝固组织没有明显相变.在100A/cm2~150A/cm2内,同未辐照表面相比,显微硬度提高1.25倍.硬度增加的主要原因是表面快速凝固组织产生硬化相和基体相中化学成分的重新分布、碳元素的烧损以及晶界的强化. 展开更多
关键词 XRD SEM EDS
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As Could We Assure Safety in Large-Scale Manufacturing of Nanoparticles for the Biomedical Use
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作者 Kirill Serguey Maksimov Serguei Kirillovich Maksimov Nikolay Dmitrievich Soukhov 《Journal of Biomaterials and Nanobiotechnology》 2011年第5期601-613,共13页
Nanoparticles provide great advantages but also great risks. Risks associating with nanoparticles are the problem of all technologies, but they increase in many times in nanotechnologies. Adequate methods of outgoing ... Nanoparticles provide great advantages but also great risks. Risks associating with nanoparticles are the problem of all technologies, but they increase in many times in nanotechnologies. Adequate methods of outgoing production inspection are necessary to solve the problem of risks, and the inspection must be based on the safety standard. Existing safety standard results from a principle of “maximum permissible concentrations or MPC”. This principle is not applicable to nanoparticles, but a safety standard reflecting risks inherent in nanoparticles doesn’t exist. Essence of the risks is illustrated by the example from pharmacology, since its safety assurance is conceptually based on MPC and it has already come against this problem. Possible formula of safety standard for nanoparticles is reflected in many publications, but conventional inspection methods cannot provide its realization, and this gap is an obstacle to assumption of similar formulas. Therefore the development of nanoparticle industry as a whole (also development of the pharmacology in particular) is impossible without the creation of an adequate inspection method. There are suggested new inspection methods founded on the new physical principle and satisfying to the adequate safety standard for nanoparticles. These methods demonstrate that creation of the adequate safety standard and the outgoing production inspection in a large-scale manufacturing of nanoparticles are the solvable problems. However there is a great distance between the physical principle and its hardware realization, and a transition from the principle to the hardware demands great intellectual and material costs. Therefore it is desirable to call attention of the public at large to the necessity of urgent expansions of investigations associated with outgoing inspections in nanoparticles technologies. It is necessary also to attract attention, first, of representatives of state structures controlling approvals of the adequate safety standard to this problem, since it is impossible to compel producers providing the safety without the similar standard, and, second, of leaders of pharmacological industry, since their industry already entered into the nanotechnology era, and they have taken an interest in a forthcoming development of inspection methods. 展开更多
关键词 Risks of NANOPARTICLE LARGE-SCALE MANUFACTURING Adequate SAFETY Standard Outgoing Production Inspection Structure and HABIT Scanning ELECTRON Microscopy HABIT Control by Means of Convergent Illuminating ELECTRON beams SAFETY Assurance in the NANOPARTICLE Industry Is a Solvable Problem
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Theory of Flexural Shear, Bending and Torsion for a Thin-Walled Beam of Open Section
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作者 David W. A. Rees Abdelraouf M. Sami Alsheikh 《World Journal of Mechanics》 2024年第3期23-53,共31页
Aspects of the general Vlasov theory are examined separately as applied to a thin-walled channel section cantilever beam under free-end end loading. In particular, the flexural bending and shear that arise under trans... Aspects of the general Vlasov theory are examined separately as applied to a thin-walled channel section cantilever beam under free-end end loading. In particular, the flexural bending and shear that arise under transverse shear and axial torsional loading are each considered theoretically. These analyses involve the location of the shear centre at which transverse shear forces when applied do not produce torsion. This centre, when taken to be coincident with the centre of twist implies an equivalent reciprocal behaviour. That is, an axial torsion applied concentric with the shear centre will twist but not bend the beam. The respective bending and shear stress conversions are derived for each action applied to three aluminium alloy extruded channel sections mounted as cantilevers with a horizontal principal axis of symmetry. Bending and shear are considered more generally for other thin-walled sections when the transverse loading axes at the shear centre are not parallel to the section = s centroidal axes of principal second moments of area. The fixing at one end of the cantilever modifies the St Venant free angular twist and the free warping displacement. It is shown from the Wagner-Kappus torsion theory how the end constrained warping generates an axial stress distribution that varies with the length and across the cross-section for an axial torsion applied to the shear centre. It should be mentioned here for wider applications and validation of the Vlasov theory that attendant papers are to consider in detail bending and torsional loadings applied to other axes through each of the centroid and the web centre. Therein, both bending and twisting arise from transverse shear and axial torsion applied to each position being displaced from the shear centre. Here, the influence of the axis position upon the net axial and shear stress distributions is to be established. That is, the net axial stress from axial torsional loading is identified with the sum of axial stress due to bending and axial stress arising from constrained warping displacements at the fixing. The net shear stress distribution overlays the distributions from axial torsion and that from flexural shear under transverse loading. Both arise when transverse forces are displaced from the shear centre. 展开更多
关键词 Thin Wall Theory Cantilever beam Open Channel Section Principal Axes Flexure Transverse Shear TORSION Shear Centre Shear Flow WARPING Fixed-End Constraint
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Impact of antenna and beam-selection-based sectored relay planning for 備 performance evaluation of 4G LTE-A tri-sectored cell
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作者 Javaid A. Sheikh Mehboob-ul- Amin +1 位作者 Shabir A. Parah G. Mohiuddin Bhat 《Digital Communications and Networks》 SCIE 2019年第2期121-130,共10页
The deployment of Relay Nodes (RNs) in 4G LTE-A networks, mainly originating from the wireless backhaul link, provides an excellent network planning tool to enhance system performance. Better coordination between the ... The deployment of Relay Nodes (RNs) in 4G LTE-A networks, mainly originating from the wireless backhaul link, provides an excellent network planning tool to enhance system performance. Better coordination between the base station and relays to mitigate inter-cell interference becomes an important aspect of achieving the required system performance, not only in the single-cell scenario, but also in multi-cell scenarios. In this paper, we model and analyze two basic approaches for designing a 4G LTE-A tri-sectored cellular system. The approaches are based on Antenna Selection Sectored Relaying (ASSR) and Beam Selection Sectored Relaying (BSSR). The main purpose of the proposed schemes is to enhance system performance by improving the quality of the wireless relay backhaul link. In this technique, antenna selection takes into consideration Non-Line-Of-Sight (NLOS) communication, whereas BSSR considers the case of Line-Of-Sight (LOS) communication using heuristic beam forming approach. The resource allocation problem has also been investigated for relay based cooperative LTE-A trisectored cell in the downlink. The best possible location for relay node in the sector, power allocation and MIMO channel modeling is formulated as an optimization problem with the aim of maximizing the end to end link rate and the Signal to Interference plus Noise Ratio (SINR) of 4G LTE-A systems. Power allocation/optimization has been solved by means of the duality equation of the stationary Karush-Kuhn-Tucker (KKT) cond让ion and is used to derive optimal values for the beam forming vector on both the relay as well as the access link. The performance of the proposed scheme is verified through simulations carried out using MATLAB software. The simulation results show a significant improvement in the SINR, throughput capacity, and coverage area of the 4G LTE-A cell, while guaranteeing better quality of service. 展开更多
关键词 Long Term Evolution-Advanced (LTE-A) RELAY Node (RN) Sectored RELAYING (SR) ANTENNA SELECTION Sectored RELAYING (ASSR) beam SELECTION Sectored RELAYING (BSSR) Karush-Kuhn-Tucker (KKT)
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PROGRESS IN ION BEAM ANALYSIS AT FUDAN UNIVERSITY
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作者 杨福家 汤家镛 《Nuclear Science and Techniques》 SCIE CAS CSCD 1990年第Z1期1-9,共9页
Progres in ion beam analysis at Fudan University in the recent years is briefly reviewed. Presented as examples of the research activities performed in this field are the following projects: (1) Nuclear potential reso... Progres in ion beam analysis at Fudan University in the recent years is briefly reviewed. Presented as examples of the research activities performed in this field are the following projects: (1) Nuclear potential resonance scattering of 6.25 MeV and 4.25 MeV helium ions for simultaneous compositional analysis of carbon and oxygen in a Mylar, a SnInO, and some other film samples: (2) Determination of stoichiometry of a high-temperature superconducting Y-Ba-Cu-O sample by backscattering of 8.8 MeV helium ions; (3) Backscattering and channeling analysis of multilayered structures periodically consisting of layers of pure Si and alternate layers of Ge and Si, grown on (100) Si substrates by molecular beam epitaxy: (4) Studies of surface structure of Al(100) by the use of MeV ions backscattering and channeling surface peak: and (5) MeV ion microbeam analysis and the use of PIXE method in DNA study. etc. 展开更多
关键词 ION beam ANALYSIS Non - RUTHERFORD BACKSCATTERING CHANNELING ANALYSIS of superlattice Surface structure study MeV ION MICRObeam system
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Reirradiation of recurrent breast cancer with proton beam therapy:A case report and literature review
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作者 Yi-Lan Lin 《World Journal of Clinical Oncology》 CAS 2019年第7期256-268,共13页
BACKGROUND Locoregional recurrence of breast cancer is challenging for clinicians,due to the various former treatments patients have undergone.However,treatment of the recurrence with systemic therapy and subsequent r... BACKGROUND Locoregional recurrence of breast cancer is challenging for clinicians,due to the various former treatments patients have undergone.However,treatment of the recurrence with systemic therapy and subsequent reirradiation of chest wall is accompanied by increased toxicities,particularly radiation-induced cardiovascular disease.Reirradiation by proton beam therapy(PBT)enables superior preservation of adjacent organs at risk as well as concurrent dose escalation for delivery to the gross tumor.This technology is expected to improve the overall outcome of recurrent breast cancer.CASE SUMMARY A 47-year-old female presented with an extensive locoregional recurrence at 10 yr after primary treatment of a luminal A breast cancer.Because of tumor progression despite having undergone bilateral ovarectomy and systemic therapy,the patient was treated with PBT BE total dose of 64.40 Gy to each gross tumor and 56.00 Gy to the upper mediastinal and retrosternal lymphatics including the entire sternum in 28 fractions.Follow-up computed tomography showed a partial remission,without evidence of newly emerging metastasis.At 19 mo after the PBT,the patient developed a radiation-induced pericardial disease and pleural effusions with clinical burden of dyspnea,which were successfully treated by drainage and corticosteroid.Cytological analysis of the puncture fluid showed no malignancy,and the subsequent computed tomography scan indicated stable disease as well as significantly decreased pericardial and pleural effusions.The patient remains free of progression to date.CONCLUSION PBT was a safe and effective method of reirradiation for locoregionally recurrent breast cancer in our patient. 展开更多
关键词 Proton beam therapy Recurrent breast cancer CHEST wall RECURRENCE REIRRADIATION PERICARDITIS RADIATION-INDUCED CARDIOVASCULAR disease Case report
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Nanofabrication of 50 nm zone plates through e-beam lithography with local proximity effect correction for x-ray imaging 被引量:3
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作者 Jingyuan Zhu Sichao Zhang +8 位作者 Shanshan Xie Chen Xu Lijuan Zhang Xulei Tao Yuqi Ren Yudan Wang Biao Deng Renzhong Tai Yifang Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第4期456-461,共6页
High resolution Fresnel zone plates for nanoscale three-dimensional imaging of materials by both soft and hard x-rays are increasingly needed by the broad applications in nanoscience and nanotechnology.When the outmos... High resolution Fresnel zone plates for nanoscale three-dimensional imaging of materials by both soft and hard x-rays are increasingly needed by the broad applications in nanoscience and nanotechnology.When the outmost zone-width is shrinking down to 50 nm or even below,patterning the zone plates with high aspect ratio by electron beam lithography still remains a challenge because of the proximity effect.The uneven charge distribution in the exposed resist is still frequently observed even after standard proximity effect correction(PEC),because of the large variety in the line width.This work develops a new strategy,nicknamed as local proximity effect correction(LPEC),efficiently modifying the deposited energy over the whole zone plate on the top of proximity effect correction.By this way,50 nm zone plates with the aspect ratio from 4:1 up to 15:1 and the duty cycle close to 0.5 have been fabricated.Their imaging capability in soft(1.3 keV)and hard(9 keV)x-ray,respectively,has been demonstrated in Shanghai Synchrotron Radiation Facility(SSRF)with the resolution of 50 nm.The local proximity effect correction developed in this work should also be generally significant for the generation of zone plates with high resolutions beyond 50 nm. 展开更多
关键词 FRESNEL zone PLATES electron beam LITHOGRAPHY LOCAL PROXIMITY effect correction x-ray imaging 50 NM resolution
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一带悬挑结构的计算分析与补强设计
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作者 刘铁 郑文忠 王英 《工业建筑》 CSCD 北大核心 2005年第4期15-17,共3页
哈药六厂某厂房外横墙因功能调整需由原设计的 4 90mm厚砖墙改为 6 2 0mm厚砖墙 ,为使本工程的外观造型与其近邻办公楼相协调 ,在该外横墙外侧需较原设计增设干挂石材幕墙 ,由于填充墙加厚及干挂石材幕墙等新增荷载在原设计中未予考虑 ... 哈药六厂某厂房外横墙因功能调整需由原设计的 4 90mm厚砖墙改为 6 2 0mm厚砖墙 ,为使本工程的外观造型与其近邻办公楼相协调 ,在该外横墙外侧需较原设计增设干挂石材幕墙 ,由于填充墙加厚及干挂石材幕墙等新增荷载在原设计中未予考虑 ,需对带悬挑的预应力边框架进行核算与补强加固。经核算 ,框架柱及框架梁的非悬挑区段在荷载增大后仍能满足相关设计标准的要求 ,只需对框架梁的悬挑区段进行补强加固。提出了通过在基础悬挑梁和一层顶悬挑梁间后置钢筋混凝土墙形成带边框深梁以增大悬挑结构抗力 ,减小悬挑结构裂缝和变形的加固思想和方法。 展开更多
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集中荷载作用下超高强混凝土无腹筋梁抗剪强度的试验研究 被引量:9
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作者 支运芳 王敢峰 +2 位作者 李立仁 陈永庆 甘民 《重庆工学院学报》 2005年第3期69-75,共7页
通过对18根超高强混凝土无腹筋梁(包括9根简支梁和9根约束)在集中荷载下抗剪强度的试验,观察了试件从裂缝出现到完全破坏失去承载能力全过程的试验现象,获得了试件的各阶段荷载值和各项应变值以及挠度值等试验数据,得出约束情况、剪跨... 通过对18根超高强混凝土无腹筋梁(包括9根简支梁和9根约束)在集中荷载下抗剪强度的试验,观察了试件从裂缝出现到完全破坏失去承载能力全过程的试验现象,获得了试件的各阶段荷载值和各项应变值以及挠度值等试验数据,得出约束情况、剪跨比和混凝土强度3个因素对构件抗剪强度影响 同时将试验实测值与国内外多个抗剪强度公式的混凝土项计算进行验算比较,对其用于计算超高强混凝土构件时的适用性、安全性进行了评价。 展开更多
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Seismic Behavior of Diaphragm-Through Connections of Concrete-Filled Square Steel Tubular Columns and H-Shaped Steel Beams 被引量:6
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作者 荣彬 陈志华 +1 位作者 Apostolos Fafitis 苗纪奎 《Transactions of Tianjin University》 EI CAS 2013年第3期195-201,共7页
Based on the introductions of a type of diaphragm-through connection between concrete-filled square steel tubular columns (CFSSTCs) and H-shaped steel beams,a finite element model of the connection is developed and us... Based on the introductions of a type of diaphragm-through connection between concrete-filled square steel tubular columns (CFSSTCs) and H-shaped steel beams,a finite element model of the connection is developed and used to investigate the seismic behavior of the connection.The results of the finite element model are validated by a set of cyclic loading tests.The cyclic loading tests and the finite element analyses indicate that the failure mode of the suggested connections is plastic hinge at the beam with inelastic rotation angle exceeding 0.04 rad.The suggested connections have sufficient strength,plastic deformation and energy dissipation capacity to be used in composite moment frames as beam-to-column rigid connections. 展开更多
关键词 concrete-filled square STEEL TUBULAR COLUMN H-shaped STEEL beam diaphragm-through connection seismic behavior load transfer mechanism
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