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Machine learning algorithm partially reconfigured on FPGA for an image edge detection system 被引量:1
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作者 Gracieth Cavalcanti Batista Johnny Oberg +3 位作者 Osamu Saotome Haroldo F.de Campos Velho Elcio Hideiti Shiguemori Ingemar Soderquist 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第2期48-68,共21页
Unmanned aerial vehicles(UAVs)have been widely used in military,medical,wireless communications,aerial surveillance,etc.One key topic involving UAVs is pose estimation in autonomous navigation.A standard procedure for... Unmanned aerial vehicles(UAVs)have been widely used in military,medical,wireless communications,aerial surveillance,etc.One key topic involving UAVs is pose estimation in autonomous navigation.A standard procedure for this process is to combine inertial navigation system sensor information with the global navigation satellite system(GNSS)signal.However,some factors can interfere with the GNSS signal,such as ionospheric scintillation,jamming,or spoofing.One alternative method to avoid using the GNSS signal is to apply an image processing approach by matching UAV images with georeferenced images.But a high effort is required for image edge extraction.Here a support vector regression(SVR)model is proposed to reduce this computational load and processing time.The dynamic partial reconfiguration(DPR)of part of the SVR datapath is implemented to accelerate the process,reduce the area,and analyze its granularity by increasing the grain size of the reconfigurable region.Results show that the implementation in hardware is 68 times faster than that in software.This architecture with DPR also facilitates the low power consumption of 4 mW,leading to a reduction of 57%than that without DPR.This is also the lowest power consumption in current machine learning hardware implementations.Besides,the circuitry area is 41 times smaller.SVR with Gaussian kernel shows a success rate of 99.18%and minimum square error of 0.0146 for testing with the planning trajectory.This system is useful for adaptive applications where the user/designer can modify/reconfigure the hardware layout during its application,thus contributing to lower power consumption,smaller hardware area,and shorter execution time. 展开更多
关键词 Dynamic partial reconfiguration(DPR) Field programmable gate array(FPGA)implementation Image edge detection Support vector regression(SVR) Unmanned aerial vehicle(UAV) pose estimation
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THE INTERIOR TRANSMISSION EIGENVALUE PROBLEM FOR AN ANISOTROPIC MEDIUM BY A PARTIALLY COATED BOUNDARY
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作者 向建立 严国政 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期339-354,共16页
We consider the interior transmission eigenvalue problem corresponding to the scattering for an anisotropic medium of the scalar Helmholtz equation in the case where the boundary?Ωis split into two disjoint parts and... We consider the interior transmission eigenvalue problem corresponding to the scattering for an anisotropic medium of the scalar Helmholtz equation in the case where the boundary?Ωis split into two disjoint parts and possesses different transmission conditions.Using the variational method,we obtain the well posedness of the interior transmission problem,which plays an important role in the proof of the discreteness of eigenvalues.Then we achieve the existence of an infinite discrete set of transmission eigenvalues provided that n≡1,where a fourth order differential operator is applied.In the case of n■1,we show the discreteness of the transmission eigenvalues under restrictive assumptions by the analytic Fredholm theory and the T-coercive method. 展开更多
关键词 interior transmission eigenvalue anisotropic medium partially coated boundary the analytic Fredholm theory T-coercive method
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Adaptive detection of range-spread targets in homogeneous and partially homogeneous clutter plus subspace interference
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作者 JIAN Tao HE Jia +3 位作者 WANG Bencai LIU Yu XU Congan XIE Zikeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期43-54,共12页
Adaptive detection of range-spread targets is considered in the presence of subspace interference plus Gaussian clutter with unknown covariance matrix.The target signal and interference are supposed to lie in two line... Adaptive detection of range-spread targets is considered in the presence of subspace interference plus Gaussian clutter with unknown covariance matrix.The target signal and interference are supposed to lie in two linearly independent subspaces with deterministic but unknown coordinates.Relying on the two-step criteria,two adaptive detectors based on Gradient tests are proposed,in homogeneous and partially homogeneous clutter plus subspace interference,respectively.Both of the proposed detectors exhibit theoretically constant false alarm rate property against unknown clutter covariance matrix as well as the power level.Numerical results show that,the proposed detectors have better performance than their existing counterparts,especially for mismatches in the signal steering vectors. 展开更多
关键词 adaptive detection subspace interference constant false alarm rate Gradient test partially homogeneous environment
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Data-Driven Modeling of Partially Observed Biological Systems
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作者 Wei-Hung Su Ching-Shan Chou Dongbin Xiu 《Communications on Applied Mathematics and Computation》 EI 2024年第1期739-754,共16页
We present a numerical approach for modeling unknown dynamical systems using partially observed data,with a focus on biological systems with(relatively)complex dynamical behavior.As an extension of the recently develo... We present a numerical approach for modeling unknown dynamical systems using partially observed data,with a focus on biological systems with(relatively)complex dynamical behavior.As an extension of the recently developed deep neural network(DNN)learning methods,our approach is particularly suitable for practical situations when(i)measurement data are available for only a subset of the state variables,and(ii)the system parameters cannot be observed or measured at all.We demonstrate that,with a properly designed DNN structure with memory terms,effective DNN models can be learned from such partially observed data containing hidden parameters.The learned DNN model serves as an accurate predictive tool for system analysis.Through a few representative biological problems,we demonstrate that such DNN models can capture qualitative dynamical behavior changes in the system,such as bifurcations,even when the parameters controlling such behavior changes are completely unknown throughout not only the model learning process but also the system prediction process.The learned DNN model effectively creates a“closed”model involving only the observables when such a closed-form model does not exist mathematically. 展开更多
关键词 Deep neural network(DNN) Governing equation discovery Biological system partial observation
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Improved combustion stability of biogas at different CO_(2) concentrations using inhomogeneous partially premixed stratified flames
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作者 Mohy Saad Mansour Maged Kiriakos +1 位作者 Lili Hao Mohamed Amr Serag-Eldin 《Global Energy Interconnection》 EI CSCD 2024年第4期486-502,共17页
Biogas is a renewable and clean energy source that plays an important role in the current environment of lowcarbon transition.If high-content CO_(2) in biogas can be separated,transformed,and utilized,it not only real... Biogas is a renewable and clean energy source that plays an important role in the current environment of lowcarbon transition.If high-content CO_(2) in biogas can be separated,transformed,and utilized,it not only realizes high-value utilization of biogas but also promotes carbon reduction in the biogas field.To improve the combustion stability of biogas,an inhomogeneous,partially premixed stratified(IPPS)combustion model was adopted in this study.The thermal flame structure and stability were investigated for a wide range of mixture inhomogeneities,turbulence levels,CO_(2) concentrations,air-to-fuel velocity ratios,and combustion energies in a concentric flow slot burner(CFSB).A fine-wire thermocouple is used to resolve the thermal flame structure.The flame size was reduced by increasing the CO_(2) concentration and the flames became lighter blue.The flame temperature also decreased with increase in CO_(2) concentration.Flame stability was reduced by increasing the CO_(2) concentration.However,at a certain level of mixture inhomogeneity,the concentration of CO_(2) in the IPPS mode did not affect the stability.Accordingly,the IPPS mode of combustion should be suitable for the combustion and stabilization of biogas.This should support the design of highly stabilized biogas turbulent flames independent of CO_(2) concentration.The data show that the lower stability conditions are partially due to the change in fuel combustion energy,which is characterized by the Wobbe index(WI).In addition,at a certain level of mixture inhomogeneity,the effect of the WI on flame stability becomes dominant. 展开更多
关键词 BIOGAS Renewable energy Effect of CO_(2) Combustion stability Burner design Renewable fuels partial premixed
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Small cell lung carcinoma with KIF5B-RET fusion partially responded to the 4^(th)-line therapy with anlotinib:A case report
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作者 Rui Zhang Yu-Ting He +2 位作者 Yi-Sha Liu Hang Li Feng Zhao 《World Journal of Clinical Cases》 SCIE 2024年第23期5410-5415,共6页
BACKGROUND Small cell lung cancer(SCLC)exhibits a pronounced tendency for metastasis and relapse,and the acquisition of resistance to chemotherapy and radiotherapy,leading to complexity in treatment outcomes.It is cru... BACKGROUND Small cell lung cancer(SCLC)exhibits a pronounced tendency for metastasis and relapse,and the acquisition of resistance to chemotherapy and radiotherapy,leading to complexity in treatment outcomes.It is crucial to tackle these challenges by advancing targeted therapeutic approaches in ongoing research endeavors.Variant RET fusions have been reported in several solid tumors,but are rarely reported in SCLC.CASE SUMMARY We present the first case of a KIF5B-RET fusion in a 65-year-old male patient with SCLC.To date,the patient has received the 4th line chemotherapy with anlotinib for one year and has shown a sustained favorable partial response.According to the results of next generation sequencing,this SCLC patient harbors the KIF5BRET fusion,suggesting that RET fusion could serve as a promising molecular target for SCLC treatment.Next-generation sequencing(NGS)plays a critical rolein comprehensively assessing the genotype and phenotype of cancer.CONCLUSION NGS can provide SCLC patients with personalized and targeted therapy options,thereby improving their likelihood of survival. 展开更多
关键词 KIF5B-RET fusion Small cell lung cancer Anlotinib partial response Next-generation sequencing Case report
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Improving recovery in sublevel top coal caving mining by using partially reverse drawing technique
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作者 Jinwang Zhang Dongliang Cheng +3 位作者 Jiachen Wang Shengli Yang Xiaohang Wan Xinyang Li 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第12期1655-1676,共22页
The sublevel top coal caving(SLTCC)mining technology is extensively employed in steeply inclined thick coal seams.Because of the typical characteristics of the short coal face in this mining method,a signifi-cant port... The sublevel top coal caving(SLTCC)mining technology is extensively employed in steeply inclined thick coal seams.Because of the typical characteristics of the short coal face in this mining method,a signifi-cant portion of the top coal is lost at the face end.For reducing the coal loss,the partially reverse drawing technique(PRDT)is proposed as a novel top coal drawing technique.Meanwhile,based on the Bergmark-Roos model(B-R model),a theoretical method for calculating the recovery ratio of top coal based on the top coal boundary equation and residual top coal amount is proposed.The mechanism of PRDT to reduce top coal loss at the face end is revealed by comparing with single-round sequential drawing technique(SSDT).Physical experiments and in-site observation data were used to verify the theoretical model.The results show that PRDT can effectively reduce the amount of residual coal near the roof by optimizing the shape characteristics of top coal boundary.Suggestions for improve recovery ratio in Wudong Coal Mine were given based on its face parameters. 展开更多
关键词 Sublevel top coal caving mining partially reverse drawing technique Boundary of top coal Drawing body of top coal Inclined coal seam
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Fracture behavior of sandstone with partial filling flaw under mixed-mode loading: Three-point bending tests and discrete element method
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作者 Dongdong Ma Yu Wu +4 位作者 Xiao Ma Xunjian Hu Wenbao Dong Decheng Li Lingyu Li 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第1期291-308,共18页
The fracture behavior of natural fracture in the geological reservoir subjected to filling property,affects the crack initiation and propagation under stress perturbation.Partial filling flaws were intermediate betwee... The fracture behavior of natural fracture in the geological reservoir subjected to filling property,affects the crack initiation and propagation under stress perturbation.Partial filling flaws were intermediate between open fractures and filled fractures,the fracture response may be worth exploring.In this work,the effect of the filling property of sandstone with partial filling flaws on the fracture behavior was systematically investigated based on three-point bending tests and the numerical approach of discrete element method(DEM).In the laboratory,semi-circular three-point bending tests were carried out with partial filling flaws of various filling strengths.Based on this,numerical simulations were used to further investigate the effect of the filling ratio and the inclination of the partial filling flaw on the mechanical and fracture responses,and the effect of the partial filling flaw under mixed-mode loading on the fracture mechanism was elucidated coupled with acoustic emission(AE)characteristics.The obtained results showed that the increase in filling strength and filling ratio of partial filling flaw led to an increase in peak strength,with a decreasing trend in peak strength with the inclination of partial filling flaw.In terms of crack propagation pattern,the increasing filling strength of the partial filling flaw induced the transformation of the fracture mechanism toward deflection,with a tortuosity path,while the filling ratio and inclination of partial filling flaw led to fracture mechanism change from deflection to penetration and attraction,accompanied with a larger AE event source in filler.Accordingly,the b-value based on the Gutenberg-Richter equation fluctuated between 5 and 4 at low filling ratio and inclination and remained around 5 at high filling ratio and inclination of partial filling flaw.Related results may provide an application prospective for reservoir stimulation using the natural fracture system. 展开更多
关键词 partial filling flaw Mixed-mode loading Semi-circular three-point bending Acoustic emission(AE) B-VALUE
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Unidirectional imaging with partially coherent light
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作者 Guangdong Ma Che-Yung Shen +8 位作者 Jingxi Li Luzhe Huang Çagatay I¸˘sıl Fazil Onuralp Ardic Xilin Yang Yuhang Li Yuntian Wang Md Sadman Sakib Rahman Aydogan Ozcan 《Advanced Photonics Nexus》 2024年第6期67-79,共13页
.Unidirectional imagers form images of input objects only in one direction,e.g.,from field-of-view(FOV)A to FOV B,while blocking the image formation in the reverse direction,from FOV B to FOV A.Here,we report unidirec... .Unidirectional imagers form images of input objects only in one direction,e.g.,from field-of-view(FOV)A to FOV B,while blocking the image formation in the reverse direction,from FOV B to FOV A.Here,we report unidirectional imaging under spatially partially coherent light and demonstrate high-quality imaging only in the forward direction(A→B)with high power efficiency while distorting the image formation in the backward direction(B→A)along with low power efficiency.Our reciprocal design features a set of spatially engineered linear diffractive layers that are statistically optimized for partially coherent illumination with a given phase correlation length.Our analyses reveal that when illuminated by a partially coherent beam with a correlation length of≥∼1.5λ,whereλis the wavelength of light,diffractive unidirectional imagers achieve robust performance,exhibiting asymmetric imaging performance between the forward and backward directions—as desired.A partially coherent unidirectional imager designed with a smaller correlation length of<1.5λstill supports unidirectional image transmission but with a reduced figure of merit.These partially coherent diffractive unidirectional imagers are compact(axially spanning<75λ),polarization-independent,and compatible with various types of illumination sources,making them well-suited for applications in asymmetric visual information processing and communication. 展开更多
关键词 partially coherent light diffractive neural networks machine learning optical processors unidirectional imagers.Received Aug.14 2024 revised manuscript received Sep.15 2024 accepted for publication Oct.3 2024 published online Oct.26 2024.
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二元向量输出的PartiallyBent函数(英文) 被引量:1
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作者 岳廷海 陈鲁生 符方伟 《南开大学学报(自然科学版)》 CAS CSCD 北大核心 2007年第3期31-37,共7页
把关于布尔函数的 Carlet 不等式推广到向量输出的布尔函数并且引入了向量输出的 Partially Bent函数的概念,即广义 Carlet 不等式中等式成立的向量输出布尔函数.给出了一些广义 Carlet 不等式中等式成立的充分必要条件.进一步讨论了二... 把关于布尔函数的 Carlet 不等式推广到向量输出的布尔函数并且引入了向量输出的 Partially Bent函数的概念,即广义 Carlet 不等式中等式成立的向量输出布尔函数.给出了一些广义 Carlet 不等式中等式成立的充分必要条件.进一步讨论了二元向量输出的 partially bent 函数的密码学性质. 展开更多
关键词 密码学 partially BENT函数 非线性度 线性结构
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Reflection of Oblique Incident Waves by Breakwaters with Partially-Perforated Wall 被引量:19
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作者 李玉成 刘洪杰 +1 位作者 滕斌 孙大鹏 《China Ocean Engineering》 SCIE EI 2002年第3期329-342,共14页
The reflection of oblique incident waves from breakwaters with a partially-perforated front wall is investigated. The fluid domain is divided into two sub-domains and the eigenfunction expansion method is applied to e... The reflection of oblique incident waves from breakwaters with a partially-perforated front wall is investigated. The fluid domain is divided into two sub-domains and the eigenfunction expansion method is applied to expand velocity potentials in each domain. In the eigen-expansion of the velocity potential, evanescent waves are included. Numerical results of the present model are compared with experimental data. The effect of porosity, the relative chamber width, the relative water depth in the wave absorbing chamber and the water depth in front of the structure are discussed. 展开更多
关键词 wave reflection partially perforated breakwaters oblique incident waves BREAKWATER
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The force of oblique incident wave on the breakwater with a partially perforated wall 被引量:6
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作者 LI Yucheng LIU Hongjie DONG Guohai 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第4期121-130,共10页
Wave forces induced by the interaction between the oblique incident wave and the breakwater with a partially perforated front wall is investigated. The fluid domain is divided into two sub-domains and the eigen-functi... Wave forces induced by the interaction between the oblique incident wave and the breakwater with a partially perforated front wall is investigated. The fluid domain is divided into two sub-domains and the eigen-function expansion method is applied to expanding velocity potentials in each domain. In the eigen-expansion of the velocity potential, evanescent waves are included. Numerical results of the present model are compared with other theories and a good agreement can be found between them. Experimental data have been compared with the present theoretical results. The effect of the traverse wall on wave forces has been discussed in detail. On the basis of the linear wave theory, it is shown that in the range Of engineering practice, the incident angle of wave has small influence on wave forces on the unit length of perforated caisson. 展开更多
关键词 partially perforated oblique incident wave wave force
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Distributed wireless quantum communication networks with partially entangled pairs 被引量:9
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作者 余旭涛 张在琛 徐进 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第1期66-73,共8页
Wireless quantum communication networks transfer quantum state by teleportation. Existing research focuses on maximal entangled pairs. In this paper, we analyse the distributed wireless quantum communication networks ... Wireless quantum communication networks transfer quantum state by teleportation. Existing research focuses on maximal entangled pairs. In this paper, we analyse the distributed wireless quantum communication networks with partially entangled pairs. A quantum routing scheme with multi-hop teleportation is proposed. With the proposed scheme, is not necessary for the quantum path to be consistent with the classical path. The quantum path and its associated classical path are established in a distributed way. Direct multi-hop teleportation is conducted on the selected path to transfer a quantum state from the source to the destination. Based on the feature of multi-hop teleportation using partially entangled pairs, if the node number of the quantum path is even, the destination node will add another teleportation at itself. We simulated the performance of distributed wireless quantum communication networks with a partially entangled state. The probability of transferring the quantum state successfully is statistically analyzed. Our work shows that multi-hop teleportation on distributed wireless quantum networks with partially entangled pairs is feasible. 展开更多
关键词 distributed wireless quantum communication networks partially entangled pairs routing multi-hop teleportation
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Partially hydrolyzed guar gum in pediatric functional abdominal pain 被引量:5
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作者 Claudio Romano Donatella Comito +2 位作者 Annalisa Famiani Sabrina Calamarà Italia Loddo 《World Journal of Gastroenterology》 SCIE CAS 2013年第2期235-240,共6页
AIM:To assess the effects of partially hydrolyzed guar gum(PHGG) diet supplement in pediatric chronic abdominal pain(CAP) and irritable bowel syndrome(IBS).METHODS:A randomized,double-blind pilot study was performed i... AIM:To assess the effects of partially hydrolyzed guar gum(PHGG) diet supplement in pediatric chronic abdominal pain(CAP) and irritable bowel syndrome(IBS).METHODS:A randomized,double-blind pilot study was performed in sixty children(8-16 years) with functional bowel disorders,such as CAP or IBS,diagnosed according to Rome Ⅲ criteria.All patients underwent ultrasound,blood and stool examinations to rule out any organic disease.Patients were allocated to receive PHGG at dosage of 5 g/d(n = 30) or placebo(fruitjuice n = 30) for 4 wk.The evaluation of the efficacy of fiber supplement included IBS symptom severity score(Birmingham IBS Questionnaire),severity of abdominal pain(Wong-Baker Face Pain Rating Score) and bowel habit(Bristol Stool Scale).Symptom scores were completed at 2,4,and 8 wk.The change from baseline in the symptom severity scale at the end of treatment and at 4 wk follow-up after treatment was the primary endpoint.The secondary endpoint was to evaluate compliance to supplementation with the PHGG in the pediatric population.Differences within groups during the treatment period and follow-up were evaluated by the Wilcoxon signed-rank test.RESULTS:The results of the study were assessed considering some variables,such as frequency and intensity of symptoms with modifications of the bowel habit.Both groups were balanced for baseline characteristics and all patients completed the study.Group A(PHGG group) presented a higher level of efficacy compared to group B(control group),(43% vs 5%,P = 0.025) in reducing clinical symptoms with modification of Birmingham IBS score(median 0 ± 1 vs 4 ± 1,P = 0.025),in intensity of CAP assessed with the Wong-Baker Face Pain Rating Score and in normalization of bowel habit evaluated with the Bristol Stool Scale(40% vs 13.3%,P = 0.025).In IBS subgroups,statistical analysis shown a tendency toward normalization of bowel movements,but there was no difference in the prevalence of improvement in two bowel habit subsets.PHGG was therefore better tolerated without any adverse effects.CONCLUSION:Although the cause of pediatric functional gastrointestinal disorders is not known,the results show that complementary therapy with PHGG may have beneficial effects on symptom control. 展开更多
关键词 Functional BOWEL DISORDERS partially hydrolyzed GUAR gum PEDIATRIC chronic ABDOMINAL pain Fiber diet
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Consistency of the directionality of partially coherent beams in turbulence expressed in terms of the angular spread and the far-field average intensity 被引量:5
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作者 陈晓文 季小玲 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第2期253-259,共7页
Under the quadratic approximation of the Rytov's phase structure function, this paper derives the general closed-form expressions for the mean-squared width and the angular spread of partially coherent beams in turbu... Under the quadratic approximation of the Rytov's phase structure function, this paper derives the general closed-form expressions for the mean-squared width and the angular spread of partially coherent beams in turbulence. It finds that under a certain condition different types of partially coherent beams may have the same directionality as a fully coherent Gaussian beam in free space and also in atmospheric turbulence if the angular spread is chosen as the characteristic parameter of beam directionality. On the other hand, it shows that generally, the directionality of partially coherent beams expressed in terms of the angular spread is not consistent with that in terms of the normalized far-field average intensity distribution in free space, but the consistency can be achieved due to turbulence. 展开更多
关键词 TURBULENCE partially coherent beam angular spread far-field average intensity
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Estimation of pulsed laser-induced single event transient in a partially depleted silicon-on-insulator 0.18-μm MOSFET 被引量:6
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作者 毕津顺 曾传滨 +3 位作者 高林春 刘刚 罗家俊 韩郑生 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第8期631-635,共5页
In this paper, we investigate the single event transient (SET) occurring in partially depleted silicon-on-insulator (PDSOI) metal-oxide-semiconductor (MOS) devices irradiated by pulsed laser beams. Transient sig... In this paper, we investigate the single event transient (SET) occurring in partially depleted silicon-on-insulator (PDSOI) metal-oxide-semiconductor (MOS) devices irradiated by pulsed laser beams. Transient signal characteristics of a 0.18-p.m single MOS device, such as SET pulse width, pulse maximum, and collected charge, are measured and an- alyzed at wafer level. We analyze in detail the influences of supply voltage and pulse energy on the SET characteristics of the device under test (DUT). The dependences of SET characteristics on drain-induced barrier lowering (DIBL) and the parasitic bipolar junction transistor (PBJT) are also discussed. These results provide a guide for radiation-hardened deep sub-micrometer PDSOI technology for space electronics applications. 展开更多
关键词 laser test single event transient charge collection partially depleted silicon on insulator
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Propagation properties of partially coherent Hermite-Gaussian beams through non-Kolmogorov turbulence 被引量:7
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作者 何雪梅 吕百达 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期244-252,共9页
The propagation properties of partially coherent Hermite-Gaussian beams through non-Kolmogorov atmospheric turbulence are studied. The effects of non-Kolmogorov turbulence and beam nonparaxiality on the average intens... The propagation properties of partially coherent Hermite-Gaussian beams through non-Kolmogorov atmospheric turbulence are studied. The effects of non-Kolmogorov turbulence and beam nonparaxiality on the average intensity evolution and the beam-width spreading are stressed. It is found that the evolution of the average intensity distribution and the beam-width spreading depends on the generalized exponent factor, namely, on the non-Kolmogorov turbulence strength for the paraxial case. For the non-paraxial case the effect of the turbulence is negiigibl% while the beam-width spreading becomes very large. The analytical results are illustrated numerically and interpreted physically. 展开更多
关键词 non-Kolmogorov turbulence partially coherent paraxial and non-paraxial Hermite-Gaussian beams PROPAGATION
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Scintillation of partially coherent Gaussian–Schell model beam propagation in slant atmospheric turbulence considering inner- and outer-scale effects 被引量:3
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作者 李亚清 吴振森 +1 位作者 张元元 王明军 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期409-416,共8页
Based on the modified Rytov theory and the international telecommunication union-radio (ITU-R) slant atmospheric structure constant model, the uniform scintillation index of partially coherent Gaussian-Schell model ... Based on the modified Rytov theory and the international telecommunication union-radio (ITU-R) slant atmospheric structure constant model, the uniform scintillation index of partially coherent Gaussian-Schell model (GSM) beam propa- gation in the slant path is derived from weak- to strong-turbulence regions considering inner- and outer-scale effects. The effects of wavelength of beams and inner- and outer-scale of turbulence on scintillation are analyzed numerically. Compar- ison between the scintillation of GSM beams under the von Karman spectrum and that of beams under the modified Hill spectrum is made. The results obtained show that the scintillation index obtained under the von Karman spectrum is smaller than that under the modified Hill spectrum. This study can find theory bases for the experiments of the partially coherent GSM beam propagation through atmospheric turbulence. 展开更多
关键词 atmospheric turbulence partially coherent beam scintillation atmospheric propagation
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Propagation of the off-axis superposition of partially coherent beams through atmospheric turbulence 被引量:5
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作者 张恩涛 季小玲 吕百达 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第2期571-580,共10页
The propagation properties of the off-axis superposition of partially coherent beams through atmospheric turbulence and their beam quality in terms of the mean-squared beam width w(z) and the power in the bucket (... The propagation properties of the off-axis superposition of partially coherent beams through atmospheric turbulence and their beam quality in terms of the mean-squared beam width w(z) and the power in the bucket (PIB) are studied in detail, where the effects of partial coherence, off-axis beam superposition and atmospheric turbulence are considered. The analytical expressions for the intensity, the beam width and the PIB are derived, and illustrative examples are given numerically. It is shown that the maximum intensity/max and the PIB decrease and w(z) increases as the refraction index structure constant Cn^2 increases. Therefore, the turbulence results in a degradation of the beam quality. However, the resulting partially coherent beam with a smaller value of spatial correlation parameter γ and larger values of separate distance Xd and beam number M is less affected by the turbulence than that with a larger value of y and smaller values of Xd and M. The main results obtained in this paper are explained physically. 展开更多
关键词 off-axis superposition of partially coherent beams atmospheric turbulence propagation property beam quality
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Transient response of a spherical cavity with a partially sealed shell embedded in viscoelastic saturated soil 被引量:14
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作者 刘干斌 谢康和 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第3期194-201,共8页
Based on Biot’s wave equation, this paper discusses the transient response of a spherical cavity with a partially sealed shell embedded in viscoelastic saturated soil. The analytical solution is derived for the trans... Based on Biot’s wave equation, this paper discusses the transient response of a spherical cavity with a partially sealed shell embedded in viscoelastic saturated soil. The analytical solution is derived for the transient response to an axisymmetric surface load and fluid pressure in Laplace transform domain. Numerical results are obtained by inverting the Laplace transform presented by Durbin, and are used to analyze the influences of the partial permeable property of boundary and relative rigidity of shell and soil on the transient response of the spherical cavity. It is shown that the influence of these two parameters is remarkable. The available solutions of permeable and impermeable boundary without shell are only two extreme cases of this paper. 展开更多
关键词 VISCOELASTICITY partial sealing Spherical shell Transient response
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