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Beibu Gulf Describes Development Blueprint
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作者 Zhong Weike 《China Chemical Reporter》 2007年第11期3-3,共2页
The National Development and Reform Commission(NDRC)recently characterizedthe investment developments of this year’s first two months as"rapid,stable andmoderate."China’s investment in these two months tot... The National Development and Reform Commission(NDRC)recently characterizedthe investment developments of this year’s first two months as"rapid,stable andmoderate."China’s investment in these two months totaled RMB653.5 billion,a yearlygrowth of 23.4%,compared With 24.5% in the same period of 2006.The 展开更多
关键词 Beibu Gulf describes Development Blueprint
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Information for Authors
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《Zoological Systematics》 2025年第1期I0001-I0002,共2页
The current journal is mainly focused in zoological systematics. According to Systematics Agenda 2000(1994), systematics is the science built on the following tasks: Taxonomy—the science of discovering, describing, a... The current journal is mainly focused in zoological systematics. According to Systematics Agenda 2000(1994), systematics is the science built on the following tasks: Taxonomy—the science of discovering, describing, and classifying species or groups of species(together termed taxa);Phylogenetic analysis—the discovery of the evolutionary relationships among a group of species;and Classification—the grouping of species, ultimately on the basis of evolutionary relationships. 展开更多
关键词 RELATIONSHIPS classify describing
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Multi-Distributed Sampling Method to Optimize Physical-Informed Neural Networks for Solving Optical Solitons
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作者 Huasen Zhou Zhiyang Zhang +2 位作者 Muwei Liu Fenghua Qi Wenjun Liu 《Chinese Physics Letters》 2025年第7期1-9,共9页
Optical solitons,as self-sustaining waveforms in a nonlinear medium where dispersion and nonlinear effects are balanced,have key applications in ultrafast laser systems and optical communications.Physics-informed neur... Optical solitons,as self-sustaining waveforms in a nonlinear medium where dispersion and nonlinear effects are balanced,have key applications in ultrafast laser systems and optical communications.Physics-informed neural networks(PINN)provide a new way to solve the nonlinear Schrodinger equation describing the soliton evolution by fusing data-driven and physical constraints.However,the grid point sampling strategy of traditional PINN suffers from high computational complexity and unstable gradient flow,which makes it difficult to capture the physical details efficiently.In this paper,we propose a residual-based adaptive multi-distribution(RAMD)sampling method to optimize the PINN training process by dynamically constructing a multi-modal loss distribution.With a 50%reduction in the number of grid points,RAMD significantly reduces the relative error of PINN and,in particular,optimizes the solution error of the(2+1)Ginzburg–Landau equation from 4.55%to 1.98%.RAMD breaks through the lack of physical constraints in the purely data-driven model by the innovative combination of multi-modal distribution modeling and autonomous sampling control for the design of all-optical communication devices.RAMD provides a high-precision numerical simulation tool for the design of all-optical communication devices,optimization of nonlinear laser devices,and other studies. 展开更多
关键词 multi distributed sampling nonlinear schrodinger equation describing soliton evolution residual based adaptive grid point sampling strategy optical solitonsas optical communicationsphysics informed physical informed neural networks ultrafast laser systems
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High-Precision Sub-Seafloor Velocity Building Based on Joint Tomography and Deep Learning on OBS Data in the South China Sea
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作者 Guoxin Chen Jun Li +5 位作者 Jinxin Chen Rongsen Du Yutao Liu Yuli Qi Chun-Feng Li Xingguo Huang 《Journal of Earth Science》 2025年第2期830-834,共5页
INTRODUCTION.Crustal velocity model is crucial for describing the subsurface composition and structure,and has significant implications in offshore oil and gas exploration and marine geophysical engineering(Xie et al.... INTRODUCTION.Crustal velocity model is crucial for describing the subsurface composition and structure,and has significant implications in offshore oil and gas exploration and marine geophysical engineering(Xie et al.,2024).Currently,travel time tomography is the most commonly used method for velocity modeling based on ocean bottom seismometer(OBS)data(Zhang et al.,2023;Sambolian et al.,2021).This method usually assumes that the sub-seafloor structure is layered,and therefore faces challenges in high-precision modeling with strong lateral discontinuities. 展开更多
关键词 velocity modeling time tomography marine geophysical engineering xie joint tomography describing subsurface composition structureand high precision velocity modeling offshore oil gas exploration ocean bottom seismometer obs data zhang
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New scientific basis for the 2018 U.S. Physical Activity Guidelines
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作者 Loretta DiPietro David M.Buchner +3 位作者 David X.Marquez Russell R.Pate Linda S.Pescatello Melicia C.Whitt-Glover 《Journal of Sport and Health Science》 SCIE 2019年第3期197-200,共4页
The U.S.Department of Health and Human Services convened the 2018 Physical Activity Guidelines Advisory Committee(PAGAC)and charged it with reviewing and summarizing the current scientific evidence linking physical ac... The U.S.Department of Health and Human Services convened the 2018 Physical Activity Guidelines Advisory Committee(PAGAC)and charged it with reviewing and summarizing the current scientific evidence linking physical activity to human health and function.The 2018 PAGAC Scientific Report1 serves as the basis for the Physical Activity Guidelines for Americans,2nd edition3 The 2018 Scientific Report extends the findings of the 2008 Scientific Report3 by examining a broader range of health outcomes and special populations that benefit from increased physical activity.In addition,the 2018 Scientific Report more closely examined the specific types,volumes,and intensities of physical activity that are associated with those benefits and now describes novel strategies for physical activity promotion at the population level. 展开更多
关键词 DEPARTMENT of HEALTH Services convened now describes novel
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Linear QSAR Regression Models for the Prediction of Bioconcentration Factors of Chloroanilines in Fish by Density Functional Theory 被引量:16
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作者 冯长君 杨伟华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第6期830-834,共5页
Density functional theory(DFT)-B3LYP level with the 6-311G**(d,p) basis set was used to calculate a set of molecular quantum chemical descriptors of 12 chloroanilines. Quantitative structure-activity relationshi... Density functional theory(DFT)-B3LYP level with the 6-311G**(d,p) basis set was used to calculate a set of molecular quantum chemical descriptors of 12 chloroanilines. Quantitative structure-activity relationship(QSAR) models of the bioconcentration factors(BCF) of the anilines in fish were established using some of the following calculated descriptors: EHOMO, ENHOMO, ELUMO, ENLUMO, ΔE1(= ELUMO- EHOMO), ΔE2(= ENLUMO- ENHOMO), dipole moment(μ), molecular volume(V), vibrational energy of 0 K(Ev), thermodynamic energy(E), heat capacity(Cv), entropy(Sm) and the charge of benzene ring(Qph). Using the variable selection and leaps-and-bounds regression, the quantum chemical descriptors derived directly from the molecular structures were employed to develop a linear QSAR model between the bioconcentration factors(BCF) and two descriptors(Sm, ENHOMO) of 12 chloroanilines. Statistically, the most significant one is a two-parameter linear equation with the correlation coefficient(R^2) of 0.981 and cross-validated correlation coefficient(Rcv^2) of 0.967. The established QSAR model has good stability and predictability based on the results from Rcv2 of leave-one-out cross-validation, AIC, FIT and tα/2. The quantum chemical analyses were performed from two aspects of frontier molecular orbital and entropy. The results show that two structural describers are crucial to the bioconcentration activity of chloroanilines. 展开更多
关键词 CHLOROANILINES bioconcentration factor density functional theory quantum chemical describers quantitative structure-activity relationship
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Structural Nonlinear Flutter Characteristics Analysis for an Actuator-fin System with Dynamic Stiffness 被引量:8
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作者 YANG Ning WU Zhigang YANG Chao 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2011年第5期590-599,共10页
The flutter characteristics of an actuator-fin system are investigated with structural nonlinearity and dynamic stiffness of the electric motor.The component mode substitution method is used to establish the nonlinear... The flutter characteristics of an actuator-fin system are investigated with structural nonlinearity and dynamic stiffness of the electric motor.The component mode substitution method is used to establish the nonlinear governing equations in time domain and frequency domain based on the fundamental dynamic equations of the electric motor and decelerator.The existing describing function method and a proposed iterative method are used to obtain the flutter characteristics containing preload freeplay nonlinearity when the control command is zero.A comparison between the results of frequency domain and those of time domain is studied.Simulations are carried out when the control command is not zero and further analysis is conducted when the freeplay angle is changed.The results show that structural nonlinearity and dynamic stiffness have a significant influence on the flutter characteristics.Limit cycle oscillations(LCOs)are observed within linear flutter boundary.The response of the actuator-fin system is related to the initial disturbance.In the nonlinear condition,the amplitude of the control command has an influence on the flutter characteristics. 展开更多
关键词 aeroelasticity FLUTTER actuators dynamic stiffness structural nonlinearity component mode substitution method describing functions
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Mental health in the post-COVID-19 era:challenges and the way forward 被引量:4
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作者 Ramyadarshni Vadivel Sheikh Shoib +12 位作者 Sarah El Halabi Samer El Hayek LamiaàEssam Drita Gashi Bytyçi Ruta Karaliuniene Andre Luiz Schuh Teixeira Sachin Nagendrappa Rodrigo Ramalho Ramdas Ransing Victor Pereira-Sanchez Chonnakarn Jatchavala Frances Nkechi Adiukwu Ganesh Kudva Kundadak 《General Psychiatry》 CSCD 2021年第1期44-48,共5页
The COVID-19 pandemic has posed a serious threat to global mental health.Multiple lines of evidence suggest that there is a varying yet considerable increase in mental health issues among the general population and vu... The COVID-19 pandemic has posed a serious threat to global mental health.Multiple lines of evidence suggest that there is a varying yet considerable increase in mental health issues among the general population and vulnerable groups.12 The aftermath is obscure and speculative from a social,economic,individual and public mental health perspective.Recently published studies support the existence of an emotional epidemic curve,describing a high probability of an increase in the burden of mental health issues in the post-pandemic era.34 Furthermore,previous major public health emergencies showed that more than half of the population devel-oped mental health problems and required mental health intervention.45 There is,therefore,an urgent need to reorganise existing mental health services to address the current unmet needs for mental health and to prepare for future challenges in the postpandemic era in terms of prevention and management. 展开更多
关键词 describing prevention CHALLENGES
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Species diversity of Lachnum (Helotiales, Hyaloscyphaceae) from temperate China 被引量:3
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作者 叶明 曹树青 +3 位作者 姜绍通 潘丽军 罗水忠 李兴江 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第1期20-27,共8页
Twenty-three temperate China species of Lachnum, Lachnum abnorme, L. angustum, L. brevipilosum, L. calosporum, L. calyculiforme, L. carneolum, L. ciliare, L. controversum, L. flavidulum, L. cf. fushanese, L. indicum, ... Twenty-three temperate China species of Lachnum, Lachnum abnorme, L. angustum, L. brevipilosum, L. calosporum, L. calyculiforme, L. carneolum, L. ciliare, L. controversum, L. flavidulum, L. cf. fushanese, L. indicum, L. kumaonicum, L. lushanese, L. minutum, L. montanum, L. cf. pteridophyllum, L. pygmaeum, L. sclerotii var. sclerotii, L. sclerotii var. sichuanense, L. subpygmeaum, L. tenuissimum, L. virgineum and L. willisii are reported, whose main characteristics are given in a formula of the described species, some of which are discussed below. 展开更多
关键词 Lachnum Species diversity Formula of described species
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Rough set model based on variable universe 被引量:3
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作者 Qingzhao Kong Xueer Chang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2022年第3期503-511,共9页
Rough set theory has a very good effect in information processing and knowledge discovery.In an information table,the current scholars regard all objects as a universe,and then establish various rough set models.Howev... Rough set theory has a very good effect in information processing and knowledge discovery.In an information table,the current scholars regard all objects as a universe,and then establish various rough set models.However,in the analysis of many data problems,it is more reasonable to select parts of objects which are useful to us or can meet the actual needs as a universe.Therefore,in order to make up for the deficiency of traditional models,a new model is introduced from the perspective of variable universe.Then,some interesting properties of this model,such as approximation sets,reduct of attributes and maximum part of universe,are discussed.Through the study of this paper,it can be seen that the model developed in our paper is not only more accurate but also more effective in describing uncertain knowledge. 展开更多
关键词 APPROXIMATION UNIVERSE describing
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Renal cell carcinoma: Evolving and emerging subtypes 被引量:7
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作者 Suzanne M Crumley Mukul Divatia +3 位作者 Luan Truong Steven Shen Alberto G Ayala Jae Y Ro 《World Journal of Clinical Cases》 SCIE 2013年第9期262-275,共14页
Our knowledge of renal cell carcinoma(RCC) is rapidly expanding. For those who diagnose and treat RCC, it is important to understand the new developments. In recent years, many new renal tumors have been described and... Our knowledge of renal cell carcinoma(RCC) is rapidly expanding. For those who diagnose and treat RCC, it is important to understand the new developments. In recent years, many new renal tumors have been described and defined, and our understanding of the biology and clinical correlates of these tumors is changing. Evolving concepts in Xp11 translocation carcinoma, mucinous tubular and spindle cell carcinoma, multilocular cystic clear cell RCC, and carcinoma associated with neuroblastoma are addressed within this review. Tubulocystic carcinoma, thyroid-like follicular carcinoma of kidney, acquired cystic disease-associated RCC, and clear cell papillary RCC are also described. Finally, candidate entities, including RCC with t(6;11) translocation, hybrid oncocytoma/chromophobe RCC, hereditary leiomyomatosis and RCC syndrome, and renal angiomyoadenomatous tumor are reviewed. Knowledge of these new entities is important for diagnosis, treatment and subsequent prognosis. This review provides a targeted summary of new developments in RCC. 展开更多
关键词 RENAL CELL CARCINOMA SUBTYPES Xp11 TRANSLOCATION Mucinous tubular and spindle CELL Multilocular CYSTIC clear CELL CARCINOMA associated with neuroblastoma recently described entities Clear CELL papillary RENAL CELL CARCINOMA Acquired CYSTIC kidney disease Hereditary leiomyomatosis Candidate entities RENAL CELL CARCINOMA with t(6 11)translocation
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Two new species of the genus Rhopalopsole (Plecoptera:Leuctridae) from China
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作者 钱昱含 杜予州 《Entomotaxonomia》 CSCD 北大核心 2012年第1期17-21,共5页
Two Rhopalopsole species from China are described as new to science: R. intonsa Qian & Du sp. nov. and R. siculiformis Qian & Du sp. nov..
关键词 Two Rhopalopsole species from China are described as new to science: R. intonsa Qian Du sp.nov. and R. siculiformis Qian Du sp. nov.. Plecoptera Leuctridae Rhopalopsole new species China
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Multi-harmonic equivalent modeling for a planar repetitive structure with polynomial-nonlinear joints 被引量:1
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作者 Xinyuan Li Guo Wei +2 位作者 Fushou Liu Jiaojiao Guo Dongping Jin 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2022年第9期1-11,共11页
How nonlinear joints affect the response of large space structures is an important problem to investigate.In this paper,a multi-harmonic equivalent modeling method is presented to establish a frequency-domain model of... How nonlinear joints affect the response of large space structures is an important problem to investigate.In this paper,a multi-harmonic equivalent modeling method is presented to establish a frequency-domain model of planar repetitive structures with nonlinear joints.First,at the local level,the nonlinear joint is modeled by the multi-harmonic describing function matrix.The element of the hybrid beam is obtained by the dynamic condensation of the beam-joint element.Second,at the global level,the displacement-equivalence method is used to model the multi-harmonic Euler continuum beam equivalent to the planar repetitive structure.Then,the pseudo-arc-length continuation method is applied to track the multi-harmonic trajectory of response.Afterwards,an experiment is conducted to validate the correctness of the modeling method,considering the effect of hanging rope and air damping.In the numerical studies,several simulation results indicate the similarity of response between a single-degree-of-freedom system with a single nonlinear joint and the system of the planar repetitive structure with a large number of nonlinear joints.Finally,the component of higher-order harmonics is shown to be important for predicting the resonance frequencies and amplitudes. 展开更多
关键词 Repetitive structure Multi-harmonic describing function method Nonlinear joints Harmonic response Joint eccentricity Equivalent modeling
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Structure-activity Relationship Model for Predicting the Hallucinogenic Activity of Phenylalkylamines 被引量:1
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作者 范英芳 成素丽 张佳瑛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第8期1201-1208,共8页
A Quantitative Structure-activity Relationship(QSAR) model was developed to predict the hallucinogenic activity of phenylalkylamines by Artificial Neural Network(ANN) method.Each compound was represented by the ca... A Quantitative Structure-activity Relationship(QSAR) model was developed to predict the hallucinogenic activity of phenylalkylamines by Artificial Neural Network(ANN) method.Each compound was represented by the calculated structural descriptors involving constitutional,topological,geometrical,electrostatic and quantum-chemical features of compound.The ANN method produced a nonlinear and seven-descriptor QSAR model with a standard error S = 0.0128 and a correlation coefficient R = 0.9752.The electronic properties of 75 phenylalkylamines were calculated with Gaussian 03 program at the DFT/B3LYP/6-311+G(d,p) level.The quantum chemical analyses were performed from two aspects of frontier molecular orbital and charge distribution.The results show that seven structural describers are crucial to the hallucinogenic activity of phenylalkylamines and that the para-and ortho-positions could be active sites acting as electron donors. 展开更多
关键词 phenylalkylamines QSAR ANN quantum chemical describers HALLUCINOGENS
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Analytically determining frequency and amplitude of spontaneous alpha oscillation in Jansen's neural mass model using the describing function method 被引量:1
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作者 Yao Xu Chun-Hui Zhang +1 位作者 Ernst Niebur Jun-Song Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第4期551-558,共8页
Spontaneous alpha oscillations are a ubiquitous phenomenon in the brain and play a key role in neural information processing and various cognitive functions.Jansen's neural mass model(NMM) was initially proposed to... Spontaneous alpha oscillations are a ubiquitous phenomenon in the brain and play a key role in neural information processing and various cognitive functions.Jansen's neural mass model(NMM) was initially proposed to study the origin of alpha oscillations.Most of previous studies of the spontaneous alpha oscillations in the NMM were conducted using numerical methods.In this study,we aim to propose an analytical approach using the describing function method to elucidate the spontaneous alpha oscillation mechanism in the NMM.First,the sigmoid nonlinear function in the NMM is approximated by its describing function,allowing us to reformulate the NMM and derive its standard form composed of one nonlinear part and one linear part.Second,by conducting a theoretical analysis,we can assess whether or not the spontaneous alpha oscillation would occur in the NMM and,furthermore,accurately determine its amplitude and frequency.The results reveal analytically that the interaction between linearity and nonlinearity of the NMM plays a key role in generating the spontaneous alpha oscillations.Furthermore,strong nonlinearity and large linear strength are required to generate the spontaneous alpha oscillations. 展开更多
关键词 neural mass model spontaneous alpha oscillation describing function
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Design of Robust Controller for Flexible Joint Robot with Nonlinear Friction Characteristics 被引量:1
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作者 陈健 葛连正 李瑞峰 《Journal of Donghua University(English Edition)》 EI CAS 2015年第5期737-742,共6页
A robust controller method for flexible joint robot considering the effect caused by nonlinear friction was presented.The nonlinear friction was denoted as inverse additive output uncertainty relative to the nominal m... A robust controller method for flexible joint robot considering the effect caused by nonlinear friction was presented.The nonlinear friction was denoted as inverse additive output uncertainty relative to the nominal model in our work,based on which the describing function was analyzed in frequency domain,and the weighting function of nonlinear friction was further calculated as well. By combining the friction uncertainty,the mixed sensitivity H∞optimization was proposed as the benchmark for controller design, which also leaded to good performance of robustness. Furthermore,unstructured perturbation to the system was analyzed so that the stability was guaranteed. Simulation results show that the proposed controller can provide excellent tracking and regulation performance. 展开更多
关键词 robot joints with flexibility nonlinear friction describing function method robust control
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Master equation describing the diffusion process for a coherent state 被引量:1
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作者 刘堂昆 单传家 +1 位作者 刘继兵 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期112-114,共3页
The evolution of a pure coherent state into a chaotic state is described very well by a master equation, as is validated via an examination of the coherent state's evolution during the diffusion process, fully utiliz... The evolution of a pure coherent state into a chaotic state is described very well by a master equation, as is validated via an examination of the coherent state's evolution during the diffusion process, fully utilizing the technique of integration within an ordered product (IWOP) of operators. The same equation also describes a limitation that maintains the coherence in a weak diffusion process, i.e., when the dissipation is very weak and the initial average photon number is large. This equation is dp/dt = -κ[a+ap -a+pa -apa+ + paa+]. The physical difference between this diffusion equation and the better-known amplitude damping master equation is pointed out. 展开更多
关键词 master equation describing diffusion coherent state evolution chaotic state integration within anordered product (IWOP) of operators
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Correlation Analysis of X-Band Sea Clutter in Complex Domain 被引量:2
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作者 CHENG Xiaolong JI Tingting +1 位作者 WANG Guoyu JI Guangrong 《Journal of Ocean University of China》 SCIE CAS 2016年第4期613-618,共6页
The correlation analysis of sea clutter data in a complex domain is conducted in this study. Specific to X-band sea clutter, the statistical characteristics of the complex correlation, particularly the phase character... The correlation analysis of sea clutter data in a complex domain is conducted in this study. Specific to X-band sea clutter, the statistical characteristics of the complex correlation, particularly the phase characteristics which are closely related to the phase difference of the sea clutter and the Doppler properties, are analyzed in detail based on the experimental data, recorded by the Mc Master University IPIX radar in 1993. That the phase term of the complex correlation presents linear change means that there exists the linearity of phase differences between different time intervals in the X-band sea clutter. This investigation explores the regularities about the effect of wind on the complex correlation with similar patterns for different polarization modes. The regularities indicate that the wind direction can be inferred from the distribution pattern of the complex correlation. Moreover, a model describing the relationships between the statistics of the complex correlation and wind parameters is proposed. The application for target detection based on the differences of characteristics of complex correlations between the sea clutter and the target are also investigated and the proposed features have been confirmed. The principle of the method is fundamental for broader future applications. 展开更多
关键词 clutter Correlation Domain describing fitting patch scatter correspondence descriptor normalized
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The Linguistic Means of Representing Women in the Doukhobor Russian Psalms 被引量:1
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作者 Veronika Makarova 《Journal of Literature and Art Studies》 2012年第8期814-832,共19页
This paper analyzes the language employed in the representations of women in Doukhobor Russian ritual texts called "ncanMbf' (psalms) from the viewpoint of linguistic text analysis performed in the Russian traditi... This paper analyzes the language employed in the representations of women in Doukhobor Russian ritual texts called "ncanMbf' (psalms) from the viewpoint of linguistic text analysis performed in the Russian tradition of folklore stylistics. While addressing the representations of Biblical female characters, such as the Holy Virgin Mary Magdalene, the Heavenly Bride, and the Whore of Babylon, along with the portrayals of Doukhobor and other women, the paper identifies stylistic features in their textual descriptions. The study establishes connections between Doukhobor texts and Russian folklore and liturgical tradition. The paper strives to identify the place of Doukhobor psalms as an integral part of the Russian literary and folklore heritage 展开更多
关键词 Doukhobors Doukhobor oral tradition literary style linguistic means of describing women's images RUSSIAN
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