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Folded localized excitations in the (2+1)-dimensional modified dispersive water-wave system 被引量:7
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作者 雷燕 马松华 方建平 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第1期138-142,共5页
By using a mapping approach and a linear variable separation approach, a new family of solitary wave solutions with arbitrary functions for the (2+1)-dimensional modified dispersive water-wave system (MDWW) is de... By using a mapping approach and a linear variable separation approach, a new family of solitary wave solutions with arbitrary functions for the (2+1)-dimensional modified dispersive water-wave system (MDWW) is derived. Based on the derived solutions and using some multi-valued functions, we obtain some novel folded localized excitations of the system. 展开更多
关键词 mapping approach modified dispersive water-wave system solitary wave solution folded localized excitation
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Folded Solitary Wave Excitations for(2+1)-Dimensional Nizhnik-Novikov-Veselov System 被引量:2
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作者 MA Song-Hua FANG Jian-Ping LU Zhi-Jie 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第3期479-484,共6页
With the help of an improved mapping approach and a linear-variable-separation approach, a new family of exact solutions with arbitrary functions of the (2+1)-dimensional Nizhnik-Novikov-Veselov system (NNV) is d... With the help of an improved mapping approach and a linear-variable-separation approach, a new family of exact solutions with arbitrary functions of the (2+1)-dimensional Nizhnik-Novikov-Veselov system (NNV) is derived. Based on the derived solutions and using some multi-valued functions, we find a few new folded solitary wave excitations for the (2+1)-dimensional NNV system. 展开更多
关键词 (2+1)-dimensional NNV system improved mapping approach~ multi-valued functions folded solitary wave excitations
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A Single Folded Beam Magneto-Optical Trap System for Neutral Mercury Atoms 被引量:1
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作者 刘亢亢 赵儒臣 +6 位作者 苟维 付小虎 刘洪力 尹士奇 孙剑芳 徐震 王育竹 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第7期38-41,共4页
Mercury is a promising candidate for the optical lattice clock, due to its low sensitivity to the blackbody radiation. We develop a single folded beam magneto-optical trap for the neutral mercury optical lattice clock... Mercury is a promising candidate for the optical lattice clock, due to its low sensitivity to the blackbody radiation. We develop a single folded beam magneto-optical trap for the neutral mercury optical lattice clock, with a 253. 7nm frequency quadrupled laser. Up to 1.7 × 10^6 (202Hg) or 1.5 × 10^6 (199Hg) atoms can be captured, and the atom temperature is lowered to 170μK (202Hg) or 50μK (199Hg). The cold atom signals of all six rich abundant isotopes are observed in this system. 展开更多
关键词 for of Hg A Single folded Beam Magneto-Optical Trap system for Neutral Mercury Atoms in is MOT
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Investigation of a wideband folded double-ridged waveguide slow-wave system 被引量:1
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作者 何俊 魏彦玉 +1 位作者 宫玉彬 王文祥 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第5期237-243,共7页
The folded double-ridged waveguide structure is presented and its properties used for wide-band traveling-wave tube are investigated. Expressions of dispersion characteristics, normalized phase velocity and interactio... The folded double-ridged waveguide structure is presented and its properties used for wide-band traveling-wave tube are investigated. Expressions of dispersion characteristics, normalized phase velocity and interaction impedance of this structure are derived and numerically calculated. The calculated results using our theory agree well with those obtained by using the 3D electromagnetic simulation software HFSS. Influences of the ridge-loaded area and broad-wall dimensions on the high frequency characteristics of the novel slow-wave structure are discussed. It is shown that the folded double-ridged waveguide structure has a much wider relative passband than the folded waveguide slow-wave structure and a relative passband of 67% could be obtained, indicating that this structure can operate in broad-band frequency ranges of beam-wave interaction. The small signal gain property is investigated for ensuring the improvement of bandwidth. Meanwhile, with comparable dispersion characteristics, the transverse section dimension of this novel structure is much smaller than that of conventional one, which indicates an available way to reduce the weight of traveling-wave tube. 展开更多
关键词 millimeter wave traveling-wave tube slow-wave structure folded waveguide high-frequency characteristics
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Flow field, sedimentation, and erosion characteristics around folded linear HDPE sheet sand fence: Numerical simulation study 被引量:1
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作者 ZHANG Kai ZHANG Hailong +4 位作者 TIAN Jianjin QU Jianjun ZHANG Xingxin WANG Zhenghui XIAO jianhua 《Journal of Mountain Science》 SCIE CSCD 2024年第1期113-130,共18页
Wind and sand hazards are serious in the Milan Gobi area of the Xinjiang section of the Korla Railway. In order to ensure the safe operation of railroads, there is a need for wind and sand protection in heavily sandy ... Wind and sand hazards are serious in the Milan Gobi area of the Xinjiang section of the Korla Railway. In order to ensure the safe operation of railroads, there is a need for wind and sand protection in heavily sandy areas. The wind and sand flow in the region is notably bi-directional. To shield railroads from sand, a unique sand fence made of folded linear high-density polyethylene(HDPE) is used, aligning with the principle that the dominant wind direction is perpendicular to the fence. This study employed field observations and numerical simulations to investigate the effectiveness of these HDPE sand fences in altering flow field distribution and offering protection. It also explored how these fences affect the deposition and erosion of sand particles. Findings revealed a significant reduction in wind speed near the fence corner;the minimum horizontal wind speed on the leeward side of the first sand fence(LSF) decreased dramatically from 3 m/s to 0.64 m/s. The vortex area on the LSF markedly impacted horizontal wind speeds. Within the LSF, sand deposition was a primary occurrence. As wind speeds increased, the deposition zone shrank, whereas the positive erosion zone expanded. Close to the folded corners of the HDPE sand fence, there was a notable shift from the positive erosion zone to a deposition zone. Field tests and numerical simulations confirmed the high windproof efficiency(WE) and sand resistance efficiency(SE) in the HDPE sand fence. Folded linear HDPE sheet sand fence can effectively slow down the incoming flow and reduce the sand content, thus achieving good wind and sand protection. This study provides essential theoretical guidance for the design and improvement of wind and sand protection systems in railroad engineering. 展开更多
关键词 folded linear HDPE sheet sand fence Numerical simulation Flow field characteristics Protection benefits
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The Aghajari (Upper Fars) Formation in the Folded Zagros Zone, Iran: Insights to Identify Facies, Architectural Elements, Fluvial Systems, Petrography and Provenance
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作者 Mohammad SAHRAEYAN Mohammad BAHRAMI Sayed Hassan HEJAZI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第4期1019-1031,共13页
The Aghajari Formation, called also the Upper Fars, develops throughout the Folded Zagros Zone and its thickness in the type section in southwest of Iran is 2966 meters. To analyze the sedimentary basin of this Format... The Aghajari Formation, called also the Upper Fars, develops throughout the Folded Zagros Zone and its thickness in the type section in southwest of Iran is 2966 meters. To analyze the sedimentary basin of this Formation, lithofacies, architectural elements and petrofacies of the related deposits in a section in southeast of Sarvestan in Fars Province of Iran with a thickness of 2221.45 meters were examined. Microscopically studying thin sections, the petrography and the occurrence of the deposits were determined. In this section, 16 lithofacies, 10 architectural elements and 2 sandstone petrofacies were identified. The lithofacies were divided into two major and minor groups, in which the major lithofacies consist of coarse-grained (Gh, Gp, Gt and Gm), medium-grained (Sh, Sp, St, Sl, Sm, Sr and Ss and fine-grained ones (Fm, Fl and Fsm), and the minor lithofacies were evaporative and mixed silisiclastic-carbonate. The identified architectural elements are CH, SB, GB, LA, DA, CR, CS, LV, LS, CH (FF) and FF. By combining evidences from facies analysis and architectural elements together, the Aghajari Formation was divided into three parts in which the related sedimentation environments, from top to bottom, are gravel, gravel-sand and fine-grained meandering river respectively. There have also been playas and shoreface in the lower part. Based on petrography, the sandstones of this formation were classified into two groups: litharenite and sublitharenite. The origin of these deposits (sandstones) was appointed to the recycled orogeny and the source of quartz is low and medium to high metamorphic rank. Using the field evidences, the paleocurrent direction was achieved indicating the direction of the paleocurrent from northwest to southeast at the time of deposition. It is hoped that these data can be used in the interpretation of the basin and reconstruction of the paleogeography in the local and regional scales. 展开更多
关键词 Aghajari Formation lithofacies architectural elements folded Zagros zone Iran provenance
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Interaction between two folded solitary waves for a modified Broer-Kaup system
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作者 吴晓飞 朱加民 马正义 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第12期2395-2401,共7页
By means of a Painlevé-Baicklund transformation and a multi-linear separation-of-variable approach, abundant localized coherent excitations of a modified Broer-Kaup system are derived. There appear possible phase... By means of a Painlevé-Baicklund transformation and a multi-linear separation-of-variable approach, abundant localized coherent excitations of a modified Broer-Kaup system are derived. There appear possible phase shifts for the interactions of the (2+1)-dimensional novel localized structures, which are discussed in this paper. 展开更多
关键词 modified Broer-Kaup system Backlund transformation separation-of-variable method folded localized excitations
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Multi-Band Antenna with Three Folded Monopoles for Mobile Communication Systems
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作者 Ahmad El Sayed Ahmad Alaa Choumane +1 位作者 Jean-Marie Floc’h Philippe Morgand 《Wireless Engineering and Technology》 2020年第3期23-29,共7页
This paper presents the design and the experimental characterization of a new multi-band antenna consisting of three folded monopoles dedicated to mobile communication systems. The originality of this paper is to get ... This paper presents the design and the experimental characterization of a new multi-band antenna consisting of three folded monopoles dedicated to mobile communication systems. The originality of this paper is to get the PMR (Professional or Private Mobile Radio) band with the GSM (Global System for Mobile Communications), DCS (Digital Cellular System) and UMTS (Universal Mobile Telecommunications System) bands. The main lobe of the antenna radiates in the zenith direction with a linear polarization over all bands. It is interesting to design the proposed antenna in order to obtain better performances in terms of directive radiation pattern (especially in the PMR band) in comparison with the already existing antenna systems in the wireless market for similar purposes. The prototype was studied with the software CST-MWS (Micro wave studio 2012). The antenna has been designed and successfully measured. 展开更多
关键词 Multi-Band Antenna folded Monopole Directive Radiation Pattern
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Protective benefit of folded linear HDPE board sand fences along the Golmud-Korla Railway,China:Field observation and wind tunnel study
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作者 ZHANG Kai TIAN Jianjin +2 位作者 WANG Zhenghui ZHANG Hailong ZHANG Xingxin 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2206-2219,共14页
The Milan Gobi area of the Golmud-Korla Railway in northwest China is located in the lower dispersal area of the mountain pass and has strong winds with evident double wind direction characteristics.This study introdu... The Milan Gobi area of the Golmud-Korla Railway in northwest China is located in the lower dispersal area of the mountain pass and has strong winds with evident double wind direction characteristics.This study introduced a novel sand fence deployment technique,termed‘folded linear deployment',designed to position the sand fence orthogonally to the two predominant wind directions for optimal protection.This study used wind tunnel and field tests to evaluate the wind and sand flow characteristics,as well as the windproof and sandresistant performance of folded linear HDPE(Highdensity polyethylene)board sand fences.The results suggest that the airflow around the fence creates clear zoning characteristics.The deceleration area on the BSF(backwind side of the sand fence)is much larger than that on the DSF(downwind side of the sand fence).Thus,sand particles are primarily deposited on the BSF.At different wind speeds,the airflow at 2 and 5 h on the DSF is not disturbed.The WSP(wind speed profile)presents a logarithmic distribution.The airflow is disturbed at 1-20 h on the BSF,and the WSP gradually deviates from the logarithmic law.However,as the airflow moves away from the fence,the WSP gradually approaches a logarithmic distribution.Meanwhile,the WPE(windproof efficiency)and SRE(sand-resistant efficiency)of the sand fence exceed 80%.In addition,the results of wind tunnel tests are compared with those of field tests.The overall dispersion is good,and the best dispersion is found at z/H=2.00,indicating good agreement between the two test results.This study provides a scientific basis for the design of sand hazard control measures,similar to the railway project in the Gobi Gale area. 展开更多
关键词 folded linear HDPE board sand fence Double wind direction Gobi area Protection benefit
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On Restricted Connectivity and Extra Connectivity of Hypercubes and Folded Hypercubes 被引量:13
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作者 徐俊明 朱强 +1 位作者 侯新民 周涛 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第2期203-207,共5页
Given a graph G and a non-negative integer h, the h-restricted connectivity κh(G) of G is the minimum cardinality of a set of vertices of G, in which at least h neighbors of any vertex is not included, if any, whos... Given a graph G and a non-negative integer h, the h-restricted connectivity κh(G) of G is the minimum cardinality of a set of vertices of G, in which at least h neighbors of any vertex is not included, if any, whose deletion disconnects G and every remaining component has the minimum degree of vertex at least h; and the h-extra connectivity κh(G) of G is the minimum cardinality of a set of vertices of G, if any, whose deletion disconnects G and every remaining component has order more than h. This paper shows that for the hypercube Qn and the folded hypercube FQn, κ1(Qn)=κ(1)(Qn)=2n-2 for n≥3, κ2(Qn)=3n-5 for n≥4, κ1(FQn)=κ(1)(FQn)=2n for n≥4 and κ(2)(FQn)=4n-4 for n≥8. 展开更多
关键词 CONNECTIVITY conditional connectivity restricted connectivity extra connectivity HYPERCUBE folded hypercube
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Fabrication and Mechanical Testing of Ultralight Folded Lattice-CoreSandwich Cylinders 被引量:6
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作者 Wanxin Li Qing Zheng +1 位作者 Hualin Fan Bin Ji 《Engineering》 SCIE EI 2020年第2期196-204,共9页
In this research,two novel folded lattice-core sandwich cylinders were designed,manufactured,and tested.The lattice core has periodic zigzag corrugations,whose ridges and valleys are directed axially or circumferentia... In this research,two novel folded lattice-core sandwich cylinders were designed,manufactured,and tested.The lattice core has periodic zigzag corrugations,whose ridges and valleys are directed axially or circumferentially.Free vibration and axial compression experiments were performed to reveal the fundamental frequency,free vibration modes,bearing capacity,and failure mode of the cylinder.A folded lattice core effectively restricts local buckling by reducing the dimension of the local skin periodic cell,and improves the global buckling resistance by enhancing the shear stiffness of the sandwich core.The cylinders fail at the mode of material failure and possess excellent load-carrying capacity.An axially directed folded sandwich cylinder has greater load-carrying capacity,while a circumferentially directed folded sandwich cylinder has higher fundamental frequencies.These two types of folded lattices provide a selection for engineers when designing a sandwich cylinder requiring strength or vibration.This research also presents a feasible way to fabricate a large-dimensional folded structure and promote its engineering application. 展开更多
关键词 folded lattice-core SANDWICH CYLINDER FABRICATION MECHANICAL TESTING
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Bifurcation and catastrophe of seepage flow system in broken rock 被引量:5
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作者 MIAO Xie-xing LI Shun-cai CHEN Zhan-qing 《Mining Science and Technology》 EI CAS 2009年第1期1-7,共7页
The study of dynamical behavior of water or gas flows in broken rock is a basic research topic among a series of key projects about stability control of the surrounding rocks in mines and the prevention of some disast... The study of dynamical behavior of water or gas flows in broken rock is a basic research topic among a series of key projects about stability control of the surrounding rocks in mines and the prevention of some disasters such as water inrush or gas outburst and the protection of the groundwater resource. It is of great theoretical and engineering importance in respect of promo- tion of security in mine production and sustainable development of the coal industry. According to the non-Darcy property of seepage flow in broken rock dynamic equations of non-Darcy and non-steady flows in broken rock are established. By dimensionless transformation, the solution diagram of steady-states satisfying the given boundary conditions is obtained. By numerical analysis of low relaxation iteration, the dynamic responses corresponding to the different flow parameters have been obtained. The stability analysis of the steady-states indicate that a saddle-node bifurcaton exists in the seepage flow system of broken rock. Consequently, using catastrophe theory, the fold catastrophe model of seepage flow instability has been obtained. As a result, the bifurcation curves of the seepage flow systems with different control parameters are presented and the standard potential function is also given with respect to the generalized state variable for the fold catastrophe of a dynamic system of seepage flow in broken rock. 展开更多
关键词 broken rock non-Darcy flow STABILITY saddle-node bifurcation fold catastrophe
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Composite active control system of roof and side truss cable for large section coal roadway in fold coal pillar area 被引量:5
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作者 Sheng-Rong XIE Er-Peng LI Fu-Lian HE Shou-Bao ZHANG Guang-Chao ZHANG Mao-Yu PANG 《Journal of Coal Science & Engineering(China)》 2013年第2期126-132,共7页
In order to solve the surrounding rock control problem of large section gangue replacement roadway under complicated conditions, this paper analyzed the impact to the roadway controlling produced by the geological con... In order to solve the surrounding rock control problem of large section gangue replacement roadway under complicated conditions, this paper analyzed the impact to the roadway controlling produced by the geological conditions such as high ground stress, folded structure tilted roof asymmetry and soft wall rock, and built the tilt layered roof structural mechanics model to clarify the increase span mechanism of the weak coal instability. Then, we proposed the combined control system including roof inclined truss cable, coal-side cable-channel steel and intensive bolt support. And then by building the structural mechanics model of roof inclined truss cable system, the support principle was described. Besides, according to this model, we deduced the calculation formula of cable anchoring force and its tensile stress. Finally surrounding rock control technology of large section roadway in fold coal pillar area was formed. Field practice shows that the greatest roof convergence of gangue replacement roadway is 158 mm and coal-side deformation is 243 mm. Roadway deformation is controlled effectively and technical support is provided for replacement mining. 展开更多
关键词 fold coal pillar area increase span mechanism roof inclined truss cable system coal-side cable-channel steel structural mechanics model
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The Unique Folding Style in the Zagros Simply Folded Belt, the Kuh-e Qazi Anticline, South Iran 被引量:5
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作者 Zahra Maleki 《Open Journal of Geology》 2015年第7期514-526,共13页
The study area is located in the Zagros Simply Folded Belt of Iran and in the interior Fars sub-basin (175 km from Persian Gulf). The Zagros fold-thrust belt is home to one of the largest petroleum producing reservoir... The study area is located in the Zagros Simply Folded Belt of Iran and in the interior Fars sub-basin (175 km from Persian Gulf). The Zagros fold-thrust belt is home to one of the largest petroleum producing reservoirs in the world. Structures in this area have complications and the study anticline has unique structures in the Fars region. In the study area, the Kuh-e Qazi anticline due to special fold style and rotation toward Northeast is the unique structure between anticlines of the Zagros belt. This anticline is fault bend fold and plunge of the anticline in eastern part rotated toward Northeast along with the Nezamabad fault trend. In this area, the Kuh-e Qazi anticline has asymmetric structures and some faults such as the Nezamabad and the Sarvestan strike slip fault effect on this anticline. The geometry of anticlines in the Zagros fold-thrust belt is affected by the type of deformation and mechanical behavior of stratigraphic units specially detachment units. The purpose of this research is to determine of folding pattern of the Kuh-e Qazi anticline and define structural features affected on them in the study area. This paper presents a part of the results of a regional study of the Fars province in the Zagros Simply Folded Belt, based on original fieldwork, satellite images, structural sections, geological maps and well data. Also, we use some software as Global Mapper and Tectonics FP for preparing some data.?Based on the research, which have been done, the boundary between ductile and frictional substrates causes rotation as a result of lateral, along-strike migration of the ductile substrate. The ductile or viscose layer in the study area is Hormuz Series. Due to lack or thinning of Hormuz salt over the Gavbandi basement high and in the eastern side of the Nezamabad basement fault, causes translation of strain and anticlockwise rotation in Southeast of the Kuh-e Qazi anticline toward Northwest unlike foreland basin due to the Nezamabad fault activity. This style between all of the anticlines in the study area is unique that rotates unlike foreland basin. In addition, influence on anticlockwise rotation, extensional stress has been created and then salt dome cropping out in Southeast of the Kuh-Qazi anticline. One of the best evidence for effect of extensional stress is triangular facets in this part of the study anticline. Based on folding analysis (geometry of axial plane and fold orientation), it is clearly confirmed that the translation of strain and anticlockwise rotation in Southeast of the Kuh-e Qazi anticline toward Northwest has been formed by basement fault activity as the Nezamabad fault in the boundary between ductile and frictional substrates of the study area. 展开更多
关键词 ZAGROS Iran Kuh-e Qazi ANTICLINE Rotation FOLD STYLE Nezamabad Fault
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A new method of complicated folded fabric modeling 被引量:2
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作者 程涵 余莉 殷柱伟 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第2期43-46,共4页
In order to resolve the complicated folded fabric modeling problem and establish the high quality finite element model for fabric working simulation in aviation or aerospace area,the Fluid Structure Interaction(FSI) m... In order to resolve the complicated folded fabric modeling problem and establish the high quality finite element model for fabric working simulation in aviation or aerospace area,the Fluid Structure Interaction(FSI) method based on Arbitrary Lagrangian Eulerian(ALE) coupling theory was applied for modeling in this paper.An expanded three-dimensional fabric model(a special airbag) was divided into several segments.Then the folded state of each was calculated based on this numerical method.At last,the completely folded finite element model was obtained.This method can effectively simulate the complicated and natural folds,and the quality of model is very high which can greatly improve the success rate of fabric working process simulation.This method also can be guidance for other kinds of folded fabric modeling. 展开更多
关键词 FABRIC FOLD ALE FSI inflatable structure
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The study of synchronization in the periodic nonuniform folded waveguide 被引量:1
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作者 徐翱 王文祥 +1 位作者 魏彦玉 宫玉彬 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第2期810-814,共5页
The periodic nonuniform folded waveguides are special structures, the physical dimension of which is between the periodic folded waveguide and the tapering period folded waveguide. Therefore, the synchronization betwe... The periodic nonuniform folded waveguides are special structures, the physical dimension of which is between the periodic folded waveguide and the tapering period folded waveguide. Therefore, the synchronization between the microwave and the electron beam can be maintained in the whole interaction process and the periods are not tapered. In comparison with the tapering period folded waveguide, the theoretical analysis and the technological requirements for this structure are more convenient. In order to study this structure, the space harmonics are analysed, the conditions to make the rn-th space harmonic synchronizing with the electron beam in the whole interaction process are present, and the dispersion curve and the coupling impedance curve are obtained by the simulation software HFSS. 展开更多
关键词 folded waveguide NONUNIFORM SYNCHRONIZATION physical dimension
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Theoretical models for designing a 220-GHz folded waveguide backward wave oscillator 被引量:1
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作者 蔡金赤 胡林林 +3 位作者 马国武 陈洪斌 金晓 陈怀璧 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第6期245-252,共8页
In this paper, the basic equations of beam-wave interaction for designing the 220 GHz folded waveguide (FW) backward wave oscillator (BWO) are described. On the whole, these equations are mainly classified into sm... In this paper, the basic equations of beam-wave interaction for designing the 220 GHz folded waveguide (FW) backward wave oscillator (BWO) are described. On the whole, these equations are mainly classified into small signal model (SSM), large signal model (LSM), and simplified small signal model (SSSM). Using these linear and nonlinear one-dimensional (1D) models, the oscillation characteristics of the FW BWO of a given configuration of slow wave struc- ture (SWS) can be calculated by numerical iteration algorithm, which is more time efficient than three-dimensional (3D) particle-in-cell (PIC) simulation. The SSSM expressed by analytical formulas is innovatively derived for determining the initial values of the FW SWS conveniently. The dispersion characteristics of the FW are obtained by equivalent circuit analysis. The space charge effect, the end reflection effect, the lossy wall effect, and the relativistic effect are all considered in our models to offer more accurate results. The design process of the FW BWO tube with output power of watt scale in a frequency range between 215 GHz and 225 GHz based on these 1D models is demonstrated. The 3D PIC method is adopted to verify the theoretical design results, which shows that they are in good agreement with each other. 展开更多
关键词 TERAHERTZ folded waveguide backward wave oscillator theoretical models
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Material Properties and Mold Folded Core Based on Ultra-violet Cured Resins 被引量:1
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作者 Wang Zhijin Valentin Khaliulin +1 位作者 Vitality Kovalev Oskar Khamidullin 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第5期529-535,共7页
Ultra-violet(UV)curing is an efficient method for composite molding.Firstly,thermophysical properties of UV cured glass-fiber reinforced plastics are conducted.Material properties are studied for various kinds of post... Ultra-violet(UV)curing is an efficient method for composite molding.Firstly,thermophysical properties of UV cured glass-fiber reinforced plastics are conducted.Material properties are studied for various kinds of postcuring modes.Then the UV curing method is suggested in manufacturing V-crimp folded core for sandwich panels.Two kinds of processing schemes for V-crimp folded core manufacturing using UV curing are presented.Finally,the effect of post-curing on the mechanical properties of folded core sandwiches is experimentally studied,and optimum modes of post-curing are determined.The experimental results show that the ultimate compressive strength of the folded sandwiches is increased by 60% after post-curing with the optimum post-curing mode. 展开更多
关键词 glass-fiber reinforced plastic composites ultra-violet(UV)curing V-crimp strength of folded core
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Plants and Animals as Concept Generators for the Development of Biomimetic Cable Entry Systems 被引量:1
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作者 Tom Masselter Uwe Scharf Thomas Speck 《Journal of Bionic Engineering》 SCIE EI CSCD 2008年第2期167-173,共7页
Many animals and plants have high potential to serve as concept generators for developing biomimetic materials and structures. We present some ideas based on structural and functional properties of plants and animals ... Many animals and plants have high potential to serve as concept generators for developing biomimetic materials and structures. We present some ideas based on structural and functional properties of plants and animals that led to the development of two types ofbiomimetic cable entry systems. Those systems have been realized on the level of functional demonstrators. 展开更多
关键词 BIONICS biomimetics cable entry STENTS folding structures
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Research on a Folded Blumlein Line Using Kapton Film as Dielectrics 被引量:1
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作者 欧阳佳 刘永贵 +2 位作者 刘金亮 王明星 冯加怀 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第2期231-234,共4页
In this project, a Blumlein line with a folded parallel-plates configuration using Kapton film as dielectrics was investigated. The characteristic parameters of this Blumlein line were analysed theoretically. The elec... In this project, a Blumlein line with a folded parallel-plates configuration using Kapton film as dielectrics was investigated. The characteristic parameters of this Blumlein line were analysed theoretically. The electric field distributions under different inner radii of the folded part were simulated. The output waveforms on the match load were also simulated by means of an equivalent electric circuit. According to the results of the theoretecal analysis and simulation, a Blumlein line with the folded parallel-plates configuration with an output voltage of 500 kV, a pulse duration of 100 ns, and a characteristic impedance of 4.773Ω was designed and manufactured. The experimental results properly demonstrated the wave transmitting process in the Blumlein line, and provided the voltage waveform of 500 kV and the current waveform of 50 kA with a pulse duration of 150 ns. Some engineering problems such as the edge electric breakdown and measuring precision by a resistance divider were revealed, which must be solved in future work to produce a more compact transmission line. 展开更多
关键词 folded Blumlein line compact pulsed power system Kapton film electromagnetic field distribution
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