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Correction:A novel method for simultaneous measurement of ^(222)Rn and ^(220)Rn progeny concentrations measured by an alpha spectrometer
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作者 Zhong-Kai Fan Jia-Le Sun +5 位作者 Hao-Xuan Li Xiang-Ming Cai Hui Yang Shou-Kang Qiu Yan-Liang Tan Jian Shan 《Nuclear Science and Techniques》 2025年第2期157-157,共1页
Correction to:Nuclear Science and Techniques(2024)36:8 https://doi.org/10.1007/s41365-024-01570-7 In this article the affiliation details for Author Jian Shan were incorrectly given as‘College of Physics and Electron... Correction to:Nuclear Science and Techniques(2024)36:8 https://doi.org/10.1007/s41365-024-01570-7 In this article the affiliation details for Author Jian Shan were incorrectly given as‘College of Physics and Electronic Engi-neering,Hengyang Normal University,Hengyang 421008,China’but should have been‘School of Nuclear Science and Technology,University of South China,Hengyang 421001,China’.The original article has been corrected. 展开更多
关键词 DETAILS simultaneous corrected
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An approximate analytical model for unconventional reservoir considering variable matrix blocks and simultaneous matrix depletion
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作者 Kai-Xuan Qiu Jia Li +2 位作者 Dong Feng Shi-Ming Wei Gang Lei 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期352-365,共14页
In regard to unconventional oil reservoirs,the transient dual-porosity and triple-porosity models have been adopted to describe the fluid flow in the complex fracture network.It has been proven to cause inaccurate pro... In regard to unconventional oil reservoirs,the transient dual-porosity and triple-porosity models have been adopted to describe the fluid flow in the complex fracture network.It has been proven to cause inaccurate production evaluations because of the absence of matrix-macrofracture communication.In addition,most of the existing models are solved analytically based on Laplace transform and numerical inversion.Hence,an approximate analytical solution is derived directly in real-time space considering variable matrix blocks and simultaneous matrix depletion.To simplify the derivation,the simultaneous matrix depletion is divided into two parts:one part feeding the macrofractures and the other part feeding the microfractures.Then,a series of partial differential equations(PDEs)describing the transient flow and boundary conditions are constructed and solved analytically by integration.Finally,a relationship between oil rate and production time in real-time space is obtained.The new model is verified against classical analytical models.When the microfracture system and matrix-macrofracture communication is neglected,the result of the new model agrees with those obtained with the dual-porosity and triple-porosity model,respectively.Certainly,the new model also has an excellent agreement with the numerical model.The model is then applied to two actual tight oil wells completed in western Canada sedimentary basin.After identifying the flow regime,the solution suitably matches the field production data,and the model parameters are determined.Through these output parameters,we can accurately forecast the production and even estimate the petrophysical properties. 展开更多
关键词 Analytical solution Unconventional reservoir Variable matrix simultaneous flow
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Simultaneous Identification of Thermophysical Properties of Semitransparent Media Using a Hybrid Model Based on Artificial Neural Network and Evolutionary Algorithm
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作者 LIU Yang HU Shaochuang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第4期458-475,共18页
A hybrid identification model based on multilayer artificial neural networks(ANNs) and particle swarm optimization(PSO) algorithm is developed to improve the simultaneous identification efficiency of thermal conductiv... A hybrid identification model based on multilayer artificial neural networks(ANNs) and particle swarm optimization(PSO) algorithm is developed to improve the simultaneous identification efficiency of thermal conductivity and effective absorption coefficient of semitransparent materials.For the direct model,the spherical harmonic method and the finite volume method are used to solve the coupled conduction-radiation heat transfer problem in an absorbing,emitting,and non-scattering 2D axisymmetric gray medium in the background of laser flash method.For the identification part,firstly,the temperature field and the incident radiation field in different positions are chosen as observables.Then,a traditional identification model based on PSO algorithm is established.Finally,multilayer ANNs are built to fit and replace the direct model in the traditional identification model to speed up the identification process.The results show that compared with the traditional identification model,the time cost of the hybrid identification model is reduced by about 1 000 times.Besides,the hybrid identification model remains a high level of accuracy even with measurement errors. 展开更多
关键词 semitransparent medium coupled conduction-radiation heat transfer thermophysical properties simultaneous identification multilayer artificial neural networks(ANNs) evolutionary algorithm hybrid identification model
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Multi-physical field null medium:new solutions for the simultaneous control of EM waves and heat flow
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作者 Sailing He Ruili Zhang Junbo Liang 《Opto-Electronic Advances》 CSCD 2024年第11期1-3,共3页
In a recent study,a research group from Taiyuan University of Technology published their findings in the journal Opto-Electronic Science with a title"Simultaneously realizing thermal and electromagnetic cloaking ... In a recent study,a research group from Taiyuan University of Technology published their findings in the journal Opto-Electronic Science with a title"Simultaneously realizing thermal and electromagnetic cloaking by multi-physical null medium."This work introduces a structure that can control simultaneously both electromagnetic waves and heat flow.For the first time,a single structure capable of cloaking both electromagnetic waves and heat flow was experimentally demonstrated.This research offers new solutions for the simultaneous control of electromagnetic waves and heat flow,and advances the hybrid design of electromagnetic compatibility and thermal management,which may have important potentials in e.g.medical applications. 展开更多
关键词 flow. simultaneous FLOW
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Quantitative Relationship Between Simultaneous Color Contrast and Hue Difference in Complex Displays
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作者 李为 汤遇春 《Journal of Beijing Institute of Technology》 EI CAS 2000年第1期25-30,共6页
To investigate quantitatively one of the parametric effects——simultaneous color contrast on color appearance and color difference evaluation in complex displays, a set of center/surround combinations of color stimu... To investigate quantitatively one of the parametric effects——simultaneous color contrast on color appearance and color difference evaluation in complex displays, a set of center/surround combinations of color stimuli were displayed on a color monitor and the perceived color shifts of test targets induced by its surrounds were measured using binocular matching method while systematically varying hue difference between target and surround. When the hue difference increased, the magnitude of color shift in test target decreased, but the deflection angle of color shift vector from constant hue line increased. Regression analyses of experimental data indicated that the relationship between hue angle difference and the magnitude of perceived color shifts could be described quantitatively by an exponential function, and a linear function could describe quantitative relationship between hue angle difference and deflection angle of color shift vector from constant hue line. 展开更多
关键词 simultaneous color contrast color perception information displays
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Simultaneous Approximation by Baskakov-Durrmeyer Operator
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作者 齐秋兰 郭顺生 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第1期38-45,共8页
In this paper, we investigate the degree of approximation by Baskakov_Durrmeyer operator for functions which derivatives have only discontinuity points of the first kind on [0,∞) with exponential growth.
关键词 OPERATORS simultaneous approximation moduli of smoothness
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Simultaneous catalytic hydrolysis of carbonyl sulfide and carbon disulfide over Al_2O_3-K/CAC catalyst at low temperature 被引量:8
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作者 Xin Sun Ping Ning +6 位作者 Xiaolong Tang Honghong Yi Kai Li Dan He Xianmang Xu Bin Huang Ruiyun Lai 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第2期221-226,共6页
In this work, a series of coal-based active carbon (CAC) catalysts loaded by A1203 were prepared by sol-gel method and used for the simulta- neous catalytic hydrolysis of carbonyl sulfide (COS) and carbon disulfi... In this work, a series of coal-based active carbon (CAC) catalysts loaded by A1203 were prepared by sol-gel method and used for the simulta- neous catalytic hydrolysis of carbonyl sulfide (COS) and carbon disulfide (CS2) at relatively low temperatures of 30-70 ℃. The influences of calcinations temperatures and operation conditions such as: reaction temperature, 02 concentration, gas hourly space velocity (GHSV) and relative humidity (RH) were also discussed respectively. The results showed that catalysts with 5.0 wt% A1203 calcined at 300 ℃ had supe- rior activity for the simultaneous catalytic hydrolysis of COS and CS2. When the reaction temperature was above 50 ℃, catalytic hydrolysis activity of COS could be enhanced but that of CS2 was inhibited. Too high RH could make the catalytic hydrolysis activities of COS and CS2 decrease. A small amount of 02 introduction could enhance the simultaneous catalytic hydrolysis activities of COS and CS2. 展开更多
关键词 carbonyl sulfide carbon disulfide simultaneous catalytic hydrolysis Al2O3-K/CAC catalysts
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Research on simultaneous localization and mapping for AUV by an improved method:Variance reduction FastSLAM with simulated annealing 被引量:5
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作者 Jiashan Cui Dongzhu Feng +1 位作者 Yunhui Li Qichen Tian 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第3期651-661,共11页
At present,simultaneous localization and mapping(SLAM) for an autonomous underwater vehicle(AUV)is a research hotspot.Aiming at the problem of non-linear model and non-Gaussian noise in AUV motion,an improved method o... At present,simultaneous localization and mapping(SLAM) for an autonomous underwater vehicle(AUV)is a research hotspot.Aiming at the problem of non-linear model and non-Gaussian noise in AUV motion,an improved method of variance reduction fast simultaneous localization and mapping(FastSLAM) with simulated annealing is proposed to solve the problems of particle degradation,particle depletion and particle loss in traditional FastSLAM,which lead to the reduction of AUV location estimation accuracy.The adaptive exponential fading factor is generated by the anneal function of simulated annealing algorithm to improve the effective particle number and replace resampling.By increasing the weight of small particles and decreasing the weight of large particles,the variance of particle weight can be reduced,the number of effective particles can be increased,and the accuracy of AUV location and feature location estimation can be improved to some extent by retaining more information carried by particles.The experimental results based on trial data show that the proposed simulated annealing variance reduction FastSLAM method avoids particle degradation,maintains the diversity of particles,weakened the degeneracy and improves the accuracy and stability of AUV navigation and localization system. 展开更多
关键词 Autonomous underwater vehicle(AUV) SONAR simultaneous localization and mapping(SLAM) Simulated annealing FASTSLAM
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Economical multiparty simultaneous quantum identity authentication based on Greenberger-Horne-Zeilinger states 被引量:6
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作者 杨宇光 温巧燕 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第8期3233-3237,共5页
A multiparty simultaneous quantum identity authentication protocol based on Creenberger-Horne-Zeilinger (GHZ) states is proposed. The multi-user can be authenticated by a trusted third party (TTP) simultaneously. ... A multiparty simultaneous quantum identity authentication protocol based on Creenberger-Horne-Zeilinger (GHZ) states is proposed. The multi-user can be authenticated by a trusted third party (TTP) simultaneously. Compared with the scheme proposed recently (Wang et al 2006 Chin. Phys. Lett. 23(9) 2360), the proposed scheme has the advantages of consuming fewer quantum and classical resources and lessening the difficulty and intensity of necessary operations. 展开更多
关键词 quantum identity authentication multiparty simultaneous quantum identity authentication Greenberger-Horne-Zeilinger state
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X-ray communication based simultaneous communication and ranging 被引量:4
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作者 宋诗斌 许录平 +1 位作者 张华 高娜 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第9期289-298,共10页
To improve the link efficiency and decrease the payloads in space explorations, a novel simultaneous communication and ranging method based on x-ray communication(XCOM) is proposed in this paper. A delicate signal s... To improve the link efficiency and decrease the payloads in space explorations, a novel simultaneous communication and ranging method based on x-ray communication(XCOM) is proposed in this paper. A delicate signal symbol structure is utilized to achieve simultaneous data transmission and range measurement. With the designed symbol structure, the ranging information is imbedded into the communication signal and transmitted with it simultaneously. The range measurement is realized by the two-way transmission of the range information. To illustrate the proposed method, firstly, the principle of the method is introduced and the signal processing procedure is presented. Then, the performance of the proposed method is analyzed theoretically in various aspects, including the acquisition probability, the bit error rate, the ranging jitter,etc. Besides, numerical experiments are conducted to verify the proposed method and evaluate the system performance.The simulation results show that the proposed method is feasible and that the system performance is influenced by the parameters concerning the signal symbol structure. Compared with the previous methods, the proposed method improves the link efficiency and is beneficial for system miniaturization and integration, which could provide a potential option for future deep space explorations. 展开更多
关键词 simultaneous communication and ranging signal design x-ray communication bit error rate
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THE BERNSTEIN TYPE INEQUALITY AND SIMULTANEOUS APPROXIMATION BY INTERPOLATION POLYNOMIALS IN COMPLEX DOMAIN 被引量:6
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作者 涂天亮 《Acta Mathematica Scientia》 SCIE CSCD 1991年第2期213-220,共8页
In this paper we investigate simultaneous approximation for arbitrary system of nodes on smooth domain in complex plane. Some results which are better than those of known theorems are obtained.
关键词 NODE THE BERNSTEIN TYPE INEQUALITY AND simultaneous APPROXIMATION BY INTERPOLATION POLYNOMIALS IN COMPLEX DOMAIN
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Passively Q-Switched Nd,Cr:YAG Laser Simultaneous Dual-Wavelength Operation at 946 nm and 1.3μm 被引量:2
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作者 林斌 张秋琳 +3 位作者 张东香 冯宝华 何京良 张景园 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第7期76-79,共4页
A diode-end-pumped Q-switched high-efficiency Nd, Cr:YAG laser with simultaneous dual-wavelength emission at 946nm and 1.3μm is demonstrated. The maximum output power of 1.93 W with simultaneous dual-wavelength oper... A diode-end-pumped Q-switched high-efficiency Nd, Cr:YAG laser with simultaneous dual-wavelength emission at 946nm and 1.3μm is demonstrated. The maximum output power of 1.93 W with simultaneous dual-wavelength operation is achieved at an absorbed pump power of 13.32 W and an absorbed slope efficiency of 15.15%. The maximum optical-optical efficiency is 14.49% with pulse widths of 16.38ns at 946nm and 26.65ns at 1.3μm. A maximum total repetition rate of 43.25 kHz is obtained. 展开更多
关键词 YAG as Passively Q-Switched Nd Cr:YAG Laser simultaneous Dual-Wavelength Operation at 946 nm and 1.3 of NM ND Cr
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PREVENTION AND TREATMENT OF REJECTION AFTER SIMULTANEOUS PANCREAS-KIDNEY TRANSPLANTATION 被引量:3
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作者 Lei Yang Yong-feng Liu Shu-rong Liu Gang Wu Jia-lin Zhang Yi-man Meng Shao-wei Shong Gui-chen Li 《Chinese Medical Sciences Journal》 CAS CSCD 2005年第3期210-213,共4页
Objective To explore methods of preventing and reversing rejection after simultaneous pancreas-kidney (SPK) transplantation. Methods Seventeen patients underwent SPK transplantation from September 1999 to September... Objective To explore methods of preventing and reversing rejection after simultaneous pancreas-kidney (SPK) transplantation. Methods Seventeen patients underwent SPK transplantation from September 1999 to September 2003 were reviewed retrospectively. Immunosuppression was achieved by a triple drug regimen consisting of cyclosporine, mycophenolate mofleil (MMF), and steroids. Three patients were treated with anti-CD3 monoclone antibody (OKT3, 5 mg·d^-1) for induction therapy for a mean period of 5-7 days. One patients received IL-2 receptor antibodies (daclizumab) in a dose of I mg·kg^-1 on the day of transplant and the 5th day posttransplant. One patient was treated with both OKT3 and daclizumab for induction. Results No primary non-functionality of either kidney or pancreas occurred in this series of transplantations. Function of all the kidney grafts recovered within 2 to 4 days after transplantation. The level of serum creatinine was 94 ± 11 μmol/L on the 7th day posttransplant. One patient experienced the accelerated rejection, resulting in the resection of the pancreas and kidney grafts because of the failure of conservative therapy. The incidence of the first rejection episodes at 3 months was 47.1% (8/17). Only the kidney was involved in 35.3% (6/17); and both the pancreas and kidney were involved in 11.8% (2/17). All these patients received a high-dose pulse of methylprednisone (0.5 g·d^-1) for 3 days. OKT3 (0.5 mg·d^-1) was administered for 7-10 days in two patients with both renal and pancreas rejection. All the grafts were successfully rescued. Conclusion Rejection, particularly acute rejection, is the major cause influencing graft function in SPK transplantation. Monitoring renal function and pancreas exocrine secretion, and reasonable application of immunosuppressants play important roles in the diagnosis and treatment of rejection. 展开更多
关键词 simultaneous pancreas-kidney transplantation REJECTION
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Simultaneously Suppressing Low-Frequency and Relaxation Oscillation Intensity Noise in a DBR Single-Frequency Phosphate Fiber Laser 被引量:3
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作者 肖瑜 李灿 +4 位作者 徐善辉 冯洲明 杨昌盛 赵齐来 杨中民 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第6期73-76,共4页
Effective multiple optoelectronic feedback circuits for simultaneously suppressing low-frequency and relaxation oscillation intensity noise in a single-frequency phosphate fiber laser are demonstrated. The forward tra... Effective multiple optoelectronic feedback circuits for simultaneously suppressing low-frequency and relaxation oscillation intensity noise in a single-frequency phosphate fiber laser are demonstrated. The forward transfer function, which relates the laser output intensity to the pump modulations, is measured and analyzed. A custom two-path feedback system operating at different frequency bands is designed to adjust the pump current directly. The relative intensity noise is decreased by 20dB from 0.2 to 5kHz and over lOdB from 5 to lOkHz. The relaxation oscillation peak is suppressed by 22dB. In addition, a long term (24h) laser instability of less than 0.05% is achieved. 展开更多
关键词 kHz simultaneously Suppressing Low-Frequency and Relaxation Oscillation Intensity Noise in a DBR Single-Frequency Phosphate Fiber Laser DBR RIN ROF
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Simultaneous saccharification and fermentation of steam-pretreated lespedeza stalks for the production of ethanol 被引量:2
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作者 Jiang Jian-xin Zhu Li-wei Wang Kun Wang Wei-gan 《Forestry Studies in China》 CAS 2006年第3期30-33,共4页
Lespedeza stalks were subjected to steam pretreatment at 210℃ for some steaming time before simultaneous saccharification and fermentation (SSF). Cellulose-derived glucose was extensively utilized by yeast during S... Lespedeza stalks were subjected to steam pretreatment at 210℃ for some steaming time before simultaneous saccharification and fermentation (SSF). Cellulose-derived glucose was extensively utilized by yeast during SSE The ethanol yields after steam pretreatment of the lespedeza stalks at 210℃ were 59.3%, 72.8% and 62.2% of the theoretically expected values when the steaming times were 2, 4 and 6 min, respectively. The highest yield from α-cellulose was 92.7% of the theoretical value. Steam explosion pretreatment of lespedeza stalks increased ethanol yields by a factor of 4.4, from 16.4% (untreated) to 72.8% (steam explosion pretreated). 展开更多
关键词 ETHANOL lespedeza stalks steam explosion simultaneous saccharification and fermentation
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Simultaneous recovery of carbon and sulfur resources from reduction of CO_2 with H_2S using catalysts 被引量:6
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作者 Hui Su Yuyang Li +3 位作者 Ping Li Yongxiu Chen Zhizhi Zhang Xiangchen Fang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第1期110-116,共7页
An approach to the simultaneous reclamation of carbon and sulfur resources from CO2 and H2S has been proposed and effectively implemented with the aid of catalysts. A brief thermodynamic study reveals the potential of... An approach to the simultaneous reclamation of carbon and sulfur resources from CO2 and H2S has been proposed and effectively implemented with the aid of catalysts. A brief thermodynamic study reveals the potential of direct reduction of CO2 with H2S(15:15 mol% balanced with N2) for selective production of CO and elemental sulfur. The experiments carried out in a fixed-bed flow reactor over the temperature range of 400–800 °C give evidence of the importance of the employment of catalysts. Both the conversions of the reactants and the selectivities of the target products can be substantially promoted over most catalysts studied. Nevertheless, little difference appears among their catalytic performance. The results also prove that the presence of CO2 can remarkably enhance H2S conversion and the sulfur yield in comparison with H2S direct decomposition. A longtime reaction test on Mg O catalyst manifests its superior durability at high temperature(700 °C) and huge gas hourly space velocity(100,000 h-1). Free radicals initiated by catalysts are supposed to dominate the reactions between CO2 and H2S. 展开更多
关键词 Carbon dioxide Hydrogen sulfide simultaneous recovery Reduction Catalyst
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Simultaneous acceleration of two kinds of ion beams in the RISP 被引量:1
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作者 Siwon Jang Eun-San Kim 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第6期70-77,共8页
The Rare Isotope Science Project (RISP) is a research complex consisting of a heavy-ion accelerator, which contains a front-end system, a super-conducting linear accelerator, an isotope separator online (ISOL) system,... The Rare Isotope Science Project (RISP) is a research complex consisting of a heavy-ion accelerator, which contains a front-end system, a super-conducting linear accelerator, an isotope separator online (ISOL) system, and an in-flight system. The original purpose of the post-linear-accelerator (post-linac) section was to accelerate either a stable driver beam derived from an electron cyclotron resonance ion source, or an unstable rare-isotope beam from an ISOL system. The post-linac lattice has now been redesigned using a novel and improved acceleration concept that allows the simultaneous acceleration of both a stable driver beam and a radioisotope beam. To achieve this, the post-linac lattice is set for a mass-to-charge ratio (A/q) that is the average of the two beams. The performance of this simultaneous two-beam acceleration is here assessed using two ion beams: 58Ni^8+ and 132Sn^20+. A beam dynamics simulation was performed using the TRACK and TraceWin codes. The resultant beam dynamics for the new RISP post-linac lattice design are examined. We also estimate the effects of machine errors and their correction on the post-linac lattice. 展开更多
关键词 Linear ACCELERATOR simultaneous two-beam ACCELERATION HEAVY-ION ACCELERATOR BEAM dynamics
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Simultaneous multiple coronary arteries thrombosis in patients with STEMI 被引量:1
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作者 Seunghwan Kim Sang-Hoon Seol +5 位作者 Dong-Hee Park Yun-Seok Song Dong-Kie Kim Ki-Hun Kim Doo-Il Kim Pil-Sang Song 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2018年第3期241-243,共3页
Simultaneous thrombosis affecting more than one coronary artery has been reported to occur in about 4.8% of the cases at the time primary percutaneous coronary intervention (PCI). Simultaneous multiple coronary arte... Simultaneous thrombosis affecting more than one coronary artery has been reported to occur in about 4.8% of the cases at the time primary percutaneous coronary intervention (PCI). Simultaneous multiple coronary arteries throm-bosis is uncommon and can lead to a fatal outcome. Careful attention should be given to identification of abnormal ECG and coronary angiography (CAG) results. The affected ves- sel should be opened timely and efficiently in an effort to save the myocardium and reduce serious complications such as congestive heart failure, ventricular arrhythmia, cardiogenic shock, or sudden cardiac death. 展开更多
关键词 MULTIPLE simultaneous STEMI THROMBOSIS
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Recursive Dictionary-Based Simultaneous Orthogonal Matching Pursuit for Sparse Unmixing of Hyperspectral Data 被引量:1
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作者 Kong Fanqiang Guo Wenjun +1 位作者 Shen Qiu Wang Dandan 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第4期456-464,共9页
The sparse unmixing problem of greedy algorithms still remains a great challenge at finding an optimal subset of endmembers for the observed data from the spectral library,due to the usually high correlation of the sp... The sparse unmixing problem of greedy algorithms still remains a great challenge at finding an optimal subset of endmembers for the observed data from the spectral library,due to the usually high correlation of the spectral library.Under such circumstances,a novel greedy algorithm for sparse unmixing of hyperspectral data is presented,termed the recursive dictionary-based simultaneous orthogonal matching pursuit(RD-SOMP).The algorithm adopts a block-processing strategy to divide the whole hyperspectral image into several blocks.At each iteration of the block,the spectral library is projected into the orthogonal subspace and renormalized,which can reduce the correlation of the spectral library.Then RD-SOMP selects a new endmember with the maximum correlation between the current residual and the orthogonal subspace of the spectral library.The endmembers picked in all the blocks are associated as the endmember sets of the whole hyperspectral data.Finally,the abundances are estimated using the whole hyperspectral data with the obtained endmember sets.It can be proved that RD-SOMP can recover the optimal endmembers from the spectral library under certain conditions.Experimental results demonstrate that the RD-SOMP algorithm outperforms the other algorithms,with a better spectral unmixing accuracy. 展开更多
关键词 hyperspectral unmixing greedy algorithm simultaneous sparse representation sparse unmixing
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The effect of wave function orthogonality on the simultaneous ionization and excitation of helium 被引量:1
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作者 刘丽娟 贾昌春 +2 位作者 张立民 陈姣姣 陈长进 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第10期247-251,共5页
Within the framework of the first-order Born approximation, the triple differential cross sections (TDCSs) for simultaneous ionization and excitation of helium are calculated. The wave function of the ejected electr... Within the framework of the first-order Born approximation, the triple differential cross sections (TDCSs) for simultaneous ionization and excitation of helium are calculated. The wave function of the ejected electron is chosen to be orthogonal or non-orthogonal to the wave function of the bound electron before ionization. It is found that the orthogonality has a strong effect on the TDCS, especially when plane waves and Coulomb waves are used to describe the projectile and the ejected electron. 展开更多
关键词 simultaneous ionization and excitation triple differential cross section (TDCS) first-order Bornapproximation ORTHOGONALITY
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