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Fuzzy Risk Assessment Method for Airborne Network Security Based on AHP-TOPSIS
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作者 Kenian Wang YuanHong Chunxiao Li 《Computers, Materials & Continua》 SCIE EI 2024年第7期1123-1142,共20页
With the exponential increase in information security risks,ensuring the safety of aircraft heavily relies on the accurate performance of risk assessment.However,experts possess a limited understanding of fundamental ... With the exponential increase in information security risks,ensuring the safety of aircraft heavily relies on the accurate performance of risk assessment.However,experts possess a limited understanding of fundamental security elements,such as assets,threats,and vulnerabilities,due to the confidentiality of airborne networks,resulting in cognitive uncertainty.Therefore,the Pythagorean fuzzy Analytic Hierarchy Process(AHP)Technique for Order Preference by Similarity to an Ideal Solution(TOPSIS)is proposed to address the expert cognitive uncertainty during information security risk assessment for airborne networks.First,Pythagorean fuzzy AHP is employed to construct an index system and quantify the pairwise comparison matrix for determining the index weights,which is used to solve the expert cognitive uncertainty in the process of evaluating the index system weight of airborne networks.Second,Pythagorean fuzzy the TOPSIS to an Ideal Solution is utilized to assess the risk prioritization of airborne networks using the Pythagorean fuzzy weighted distance measure,which is used to address the cognitive uncertainty in the evaluation process of various indicators in airborne network threat scenarios.Finally,a comparative analysis was conducted.The proposed method demonstrated the highest Kendall coordination coefficient of 0.952.This finding indicates superior consistency and confirms the efficacy of the method in addressing expert cognition during information security risk assessment for airborne networks. 展开更多
关键词 airborne networks information security risk assessment cognitive uncertainty Pythagorean fuzzy sets
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Nature:Methyl-salicylate-mediated plant airborne defense and mechanism of interaction and coevolution between plant viruses,vector insects,and host plants
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作者 He Yan Yue Jiang 《Advanced Agrochem》 2024年第2期109-110,共2页
The discipline of plant immunity has developed rapidly in the 21st century and is marked by substantial progress toward understanding the molecular mechanisms of plant immune recognition and the pathogenicity of micro... The discipline of plant immunity has developed rapidly in the 21st century and is marked by substantial progress toward understanding the molecular mechanisms of plant immune recognition and the pathogenicity of microorganisms.Here,we highlight the recent advances in plant immunity studies made by Yule Liu and his team at Tsinghua University in Beijing,China. 展开更多
关键词 airborne defense MESA Co-evolutionary mutualism
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PC-based artif icial neural network inversion for airborne time-domain electromagnetic data 被引量:8
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作者 朱凯光 马铭遥 +4 位作者 车宏伟 杨二伟 嵇艳鞠 于生宝 林君 《Applied Geophysics》 SCIE CSCD 2012年第1期1-8,114,共9页
Traditionally, airborne time-domain electromagnetic (ATEM) data are inverted to derive the earth model by iteration. However, the data are often highly correlated among channels and consequently cause ill-posed and ... Traditionally, airborne time-domain electromagnetic (ATEM) data are inverted to derive the earth model by iteration. However, the data are often highly correlated among channels and consequently cause ill-posed and over-determined problems in the inversion. The correlation complicates the mapping relation between the ATEM data and the earth parameters and thus increases the inversion complexity. To obviate this, we adopt principal component analysis to transform ATEM data into orthogonal principal components (PCs) to reduce the correlations and the data dimensionality and simultaneously suppress the unrelated noise. In this paper, we use an artificial neural network (ANN) to approach the PCs mapping relation with the earth model parameters, avoiding the calculation of Jacobian derivatives. The PC-based ANN algorithm is applied to synthetic data for layered models compared with data-based ANN for airborne time-domain electromagnetic inversion. The results demonstrate the PC-based ANN advantages of simpler network structure, less training steps, and better inversion results over data-based ANN, especially for contaminated data. Furthermore, the PC-based ANN algorithm effectiveness is examined by the inversion of the pseudo 2D model and comparison with data-based ANN and Zhody's methods. The results indicate that PC-based ANN inversion can achieve a better agreement with the true model and also proved that PC-based ANN is feasible to invert large ATEM datasets. 展开更多
关键词 Principal component analysis artificial neural network airborne time-domain electromagnetics INVERSION CONDUCTIVITY
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Synthesis and electro-optic properties of fluorine-containing polyimide 被引量:1
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作者 邱凤仙 周钰明 +2 位作者 杨艳芳 刘举正 曹庄琪 《Journal of Southeast University(English Edition)》 EI CAS 2007年第1期131-134,共4页
The fluorine-containing organic polymer was synthesized from 3, 3', 4, 4'-Bisphenyltetracarboxylic (BPDA), and 2,2-Bis (3-amino-4-hydroxyyphenyl) hexafluoropropane (6FHP). It is a first-step preparation of a p... The fluorine-containing organic polymer was synthesized from 3, 3', 4, 4'-Bisphenyltetracarboxylic (BPDA), and 2,2-Bis (3-amino-4-hydroxyyphenyl) hexafluoropropane (6FHP). It is a first-step preparation of a preimided hydroxy-containing polyimide, followed by the covalent bonding of an active chromophore, dispersed red 19 (DR19), onto the backbone of the polyimide via the Mitsunobu reaction. The nonlinear optical (NLO) containing polyimide was synthesized. The differential scanning calorimeter (DSC)and thermal gravimetric analysis (TGA) exhibited Tg and the temperature Tg at which 5 % mass losses occurring of polymer were 248 and 309 ℃, respectively. A reflective electro-optic (EO) modulator using this polymer was fabricated. The optical nonlinearities were determined to be d33 = 5. 209×10^-9 esu (poling voltage of 3.6 kV, 205 ℃) and d33 =7. 418×10^-9esu (poling voltage of 3. 8 kV, 210 ℃) by the second harmonic generation method in in-situ condition at a fundamental wavelength of 1 064 nm. The EO coefficients 733 of the polymer layer in the EO modulator were determined to be 2. 182 pm/V (poling voltage of 3.6 kV, 205 ℃) and 3. 107 pm/V (poling voltage of 3.8 kV, 210 ℃) at 1064 nm by an attenuated-total-reflection (ATR) method. 展开更多
关键词 nonlinear optical electro-optic property POLYIMIDE
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A High-Performance Silicon Electro-Optic Phase Modulator with a Triple MOS Capacitor 被引量:2
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作者 黄北举 陈弘达 +2 位作者 刘金彬 顾明 刘海军 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第12期2089-2093,共5页
We propose and analyze a novel Si-based electro-optic modulator with an improved metal-oxide-semiconductor (MOS) capacitor configuration integrated into silicon-on-insulator (SOl). Three gate-oxide layers embedded... We propose and analyze a novel Si-based electro-optic modulator with an improved metal-oxide-semiconductor (MOS) capacitor configuration integrated into silicon-on-insulator (SOl). Three gate-oxide layers embedded in the silicon waveguide constitute a triple MOS capacitor structure, which boosts the modulation efficiency compared with a single MOS capacitor. The simulation results demonstrate that the Vπ Lπ product is 2. 4V · cm. The rise time and fall time of the proposed device are calculated to be 80 and 40ps from the transient response curve, respectively,indicating a bandwidth of 8GHz. The phase shift efficiency and bandwidth can be enhanced by rib width scaling. 展开更多
关键词 carrier accumulation plasma dispersion effect electro-optic phase modulator METAL-OXIDE-SEMICONDUCTOR optoelectronic integrated circuit
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Calculation and Analysis of Near Field of Airborne Short Wave Antenna
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作者 薛正辉 高本庆 +2 位作者 刘瑞祥 吕昕 杨力 《Journal of Beijing Institute of Technology》 EI CAS 1998年第3期286-292,共7页
Aim To calculate and analyze the near field distribution of ariborne short wave antenna. Methods B-spline method was used to get the mathermatital model of a Boeing 707320Baircraft and simulate its short wave antenna ... Aim To calculate and analyze the near field distribution of ariborne short wave antenna. Methods B-spline method was used to get the mathermatital model of a Boeing 707320Baircraft and simulate its short wave antenna . FDTD (finite-difference time-domain) method are ed tO complete the calculation and analysis. Results The near field distributions on aircraft's surface were obtained, the curve and gray figures of the normalized near field value were shown. Conclusion These modeling and calculating methods can provide data foraircraft's EMC analysis and design. 展开更多
关键词 airborne short antenna near field distribution FDTD method B-SPLINE
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Mach-Zehnder Electro-Optic Polymer Modulator with C orona Poled Core Layer 被引量:3
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作者 杨晓红 杜云 +1 位作者 石志文 吴荣汉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第8期971-974,共4页
A Mach-Zehnder(MZ) electro-optic(EO) modulator are real iz ed,with three optical layers as polymer materials.The functional layer is the co rona poled crosslinkable polyurethane.The ridge waveguide is fabricated by us... A Mach-Zehnder(MZ) electro-optic(EO) modulator are real iz ed,with three optical layers as polymer materials.The functional layer is the co rona poled crosslinkable polyurethane.The ridge waveguide is fabricated by using the spin-coating,poling,photolithography and oxygen reactive ion etching(RIE) techniques.The mode and the modulation properties of these devices are demonstra ted in a micron control system,while the light source works at the wavelength of 1 31 or 1 55 micron. 展开更多
关键词 poled polymer M Z waveguide electro-optic modulator
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Three-dimensional arbitrarily anisotropic modeling for time-domain airborne electromagnetic surveys 被引量:3
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作者 黄威 贲放 +5 位作者 殷长春 孟庆敏 李文杰 廖桂香 吴珊 西永在 《Applied Geophysics》 SCIE CSCD 2017年第3期431-440,462,共11页
Electrically anisotropic strata are abundant in nature, so their study can help our data interpretation and our understanding of the processes of geodynamics. However, current data processing generally assumes isotrop... Electrically anisotropic strata are abundant in nature, so their study can help our data interpretation and our understanding of the processes of geodynamics. However, current data processing generally assumes isotropic conditions when surveying anisotropic structures, which may cause discrepancies between reality and electromagnetic data interpretation. Moreover, the anisotropic interpretation of the time-domain airborne electromagnetic (TDAEM) method is still confined to one dimensional (1D) cases, and the corresponding three-dimensional (3D) numerical simulations are still in development. In this study, we expanded the 3D TDAEM modeling of arbitrarily anisotropic media. First, through coordinate rotation of isotropic conductivity, we obtained the conductivity tensor of an arbitrary anisotropic rock. Next, we incorporated this into Maxwell's equations, using a regular hexahedral grid of vector finite elements to subdivide the solution area. A direct solver software package provided the solution for the sparse linear equations that resulted. Analytical solutions were used to verify the accuracy and feasibility of the algorithm. The proven model was then applied to analyze the effects of arbitrary anisotropy in 3D TDAEM via the distribution of responses and amplitude changes, which revealed that different anisotropy situations strongly affected the responses of TDAEM. 展开更多
关键词 Three-dimensional time-domain airborne electromagnetic arbitrary anisotropy vector finite element
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2.5D forward modeling and inversion of frequency-domain airborne electromagnetic data 被引量:1
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作者 李文奔 曾昭发 +3 位作者 李静 陈雄 王坤 夏昭 《Applied Geophysics》 SCIE CSCD 2016年第1期37-47,218,共12页
Frequency-domain airborne electromagnetics is a proven geophysical exploration method.Presently,the interpretation is mainly based on resistivity-depth imaging and onedimensional layered inversion;nevertheless,it is d... Frequency-domain airborne electromagnetics is a proven geophysical exploration method.Presently,the interpretation is mainly based on resistivity-depth imaging and onedimensional layered inversion;nevertheless,it is difficult to obtain satisfactory results for two- or three-dimensional complex earth structures using 1D methods.3D forward modeling and inversion can be used but are hampered by computational limitations because of the large number of data.Thus,we developed a 2.5D frequency-domain airborne electromagnetic forward modeling and inversion algorithm.To eliminate the source singularities in the numerical simulations,we split the fields into primary and secondary fields.The primary fields are calculated using homogeneous or layered models with analytical solutions,and the secondary(scattered) fields are solved by the finite-element method.The linear system of equations is solved by using the large-scale sparse matrix parallel direct solver,which greatly improves the computational efficiency.The inversion algorithm was based on damping leastsquares and singular value decomposition and combined the pseudo forward modeling and reciprocity principle to compute the Jacobian matrix.Synthetic and field data were used to test the effectiveness of the proposed method. 展开更多
关键词 Frequency-domain airborne electromagnetic finite element method 2.5D geoelectric model damped least-squares method
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Influence of environmental conditions on airborne infection risk in ward 被引量:1
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作者 王晋 钱华 张小松 《Journal of Southeast University(English Edition)》 EI CAS 2010年第2期266-269,共4页
In order to study the influence of parameters on airborne transmitted diseases in a hospital ward,a pollutant decay equation and a Wells-Riley model are adopted to study the relationship between the airborne infection... In order to study the influence of parameters on airborne transmitted diseases in a hospital ward,a pollutant decay equation and a Wells-Riley model are adopted to study the relationship between the airborne infection risk and the parameters such as the ventilation rate,the number of susceptible persons and the volume of the ward.The results show that the airborne infection risk can be reduced by increasing the ventilation rate.For two wards with the same air change per hour(ACH)but different volumes,the ventilation rate in a large room is higher than that in a small one.The number of the infected persons in the ward increases with the increase in the susceptible persons when the ACH is a constant.Therefore,the ventilation rate in the ward is not only estimated by the ACH but also related to the volume of the ward and the number of the susceptible persons. 展开更多
关键词 airborne transmitted diseases air change per hour(ACH) ventilation rate
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Development of analytical methods for polycyclic aromatic hydrocarbons (PAHs) in airborne particulates: A review 被引量:10
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作者 LIU Li-bin LIU Yan +3 位作者 LIN Jin-ming TANG Ning HAYAKAWA Kazuichi MAEDA Tsuneaki 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第1期1-11,共11页
In the present work, the different sample collection, pretreatment and analytical methods for polycyclic aromatic hydrocarbons (PAHs) in airborne particulates is systematacially reviewed, and the applications of the... In the present work, the different sample collection, pretreatment and analytical methods for polycyclic aromatic hydrocarbons (PAHs) in airborne particulates is systematacially reviewed, and the applications of these pretreatment and analytical methods for PAHs are compared in detail. Some comments on the future expectation are also presented. 展开更多
关键词 polycyclic aromatic hydrocarbons (PAHs) airborne particulates analytical methods REVIEW
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Effect and Prospect of Basic Geological Survey Based on Airborne Gravimetry in China 被引量:11
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作者 LI Wenyong ZHOU Jianxin +4 位作者 XIONG Shengqing GUO Zhihong LU Wenfen XU Jianchun LIU Yanxu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第1期38-47,共10页
The airborne gravimetry was an important leap and innovation in the world's history of geophysical exploration. China's first test of the airborne gravity geological survey in the onshoreoffshore transitional area o... The airborne gravimetry was an important leap and innovation in the world's history of geophysical exploration. China's first test of the airborne gravity geological survey in the onshoreoffshore transitional area of the western and southern part of the Bohai Sea was successful and effective in geology. Based on the airborne gravity data, and combining previous ground gravity, seismic and drilling data etc., we carried out the geological interpretation by forward and inverse methods. The result shows that the airborne Bouguer gravity anomaly was clear, the fracture interpretation was reliable, and the inversion depth of the main geological interfaces was relatively accurate. This airborne gravity geological survey not only filled the exploring gaps in the onshore- offshore transitional area, and realized the geological and tectonic junction between the sea and the land, but also discovered four local gravity anomalies, 11 fractures and three sags or subsags, and so on. The good geological effect of airborne gravimetry not restricted by terrain condition shows that it can be served as a new geophysical method in the exploration of complex terrain physiognomy area such as mountain, jungle, desert, marsh, onshore-offshore transitional area and so on, and has an extensive application prospect in China in the future. 展开更多
关键词 airborne gravimetry geological survey potential application onshore-offshoretransitional area
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Introduction to the airborne marine surveillance platform and its application to water quality monitoring in China 被引量:5
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作者 WANG Difeng GONG Fang +2 位作者 PAN Delu HAO Zengzhou ZHU Qiankun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2010年第2期33-39,共7页
China Marine Surveillance Force was equipped with modern aerial equipments for marine lawexecute with the advantage of functioning agilely at a large scale of surveillance coverage, providing powerful all-round safegu... China Marine Surveillance Force was equipped with modern aerial equipments for marine lawexecute with the advantage of functioning agilely at a large scale of surveillance coverage, providing powerful all-round safeguard, which is of benefit to the harmonious and sustainable development of coastal economy. Onboard the planes, three kinds of remote sensing sensors have been installed, including a marine airborne multi-spectrum scanner (MAMS), an optical-electronic platform, and an airborne hyper-spectral system AISA+. The specifications of remote sensing platforms were introduced briefly first, then examples of water quality monitoring by airborne remote sensing were presented, including the monitoring in coastal suspended material, oil-spill and abnormal warm water, etc. 展开更多
关键词 airborne remote sensing water quality monitoring multi-spectrum hyper-spectrum
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Electro-Optical Effect Measurement of Thin-Film Material Using PM Fiber Mach-Zehnder Interferometer
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作者 屠晓光 赵雷 +4 位作者 陈平 陈少武 左玉华 余金中 王启明 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第7期1012-1016,共5页
A polarization-maintaining (PM) fiber Mach-Zehnder (MZ) interferometer has been established to measure the EO effect of very thin film materials with optical anisotropy. Unlike a common MZ interferometer, all the ... A polarization-maintaining (PM) fiber Mach-Zehnder (MZ) interferometer has been established to measure the EO effect of very thin film materials with optical anisotropy. Unlike a common MZ interferometer, all the components are connected via polarization-maintaining fibers. At the same time, a polarized DFB laser with a maximum power output of 10mW is adopted as the light source to induce a large extinction ratio. Here,we take it to determine the electro-optical coefficients of a very thin superlattice structure with GaAs, KTP, and GaN as comparative samples. The measured EO coefficients show good comparability with the others. 展开更多
关键词 electro-optic effect polarization-maintaining fiber Mach-Zehnder interferometer
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Characteristic Verification and Parameter Optimization of Airbags Cushion System for Airborne Vehicle 被引量:5
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作者 WANG Hongyan HONG Huangjie +3 位作者 HAO Guixiang DENG Huaxia RUI Qiang LI Jianyang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第1期50-57,共8页
Abstract: The major methods to investigate the airbags cushion system are experimental method, thermodynamic method and finite element method (FEM). Airbags cushion systems are very complicated and very difficult t... Abstract: The major methods to investigate the airbags cushion system are experimental method, thermodynamic method and finite element method (FEM). Airbags cushion systems are very complicated and very difficult to be investigated thoroughly by such methods For experimental method, it is nearly impossible to completely analyze and optimize the cushion characteristics of airbags of airborne vehicle because of charge issue, safety concern and time constraint. Thermodynamic method fails to take the non-linear effects of large airbag deformation and varied contact conditions into consideration. For finite element method, the FE model is usually complicated and the calculation takes tens of hours of CPU time. As a result, the optimization of the design based on a nonlinear model is very difficult by traditional iterative approach method. In this paper, a model based on FEM and control volume method is proposed to simulate landing cushion process of airborne vehicle with airbags cushion system in order to analyze and optimize the parameters in airbags cushion system. At first, the performance of airbags cushion system model is verified experimentally. In airdrop test, accelerometers are fixed in 4 test points distributed over engine mount, top, bottom and side armor plate of hull to obtain acceleration curves with time. The simulation results are obtained under the same conditions of the airdrop test and the simulation results agree very well with the experimental results, which indicate the established model is valid for further optimization. To optimize the parameters of airbags, equivalent response model based on Latin Hypercube DOE and radial basis function is employed instead of the complex finite element model. Then the optimal results based on equivalent response model are obtained using simulated annealing algorithm. After optimization, the maximal acceleration of airborne vehicle landing reduces 19.83%, while the energy absorption by airbags increases 7.85%. The performance of the airbags cushion system thus is largely improved through optimization, which indicates the proposed method has the capability of solving the parameter optimization problem of airbags cushion system for airborne vehicle. 展开更多
关键词 airborne vehicle AIRBAG nonlinear finite element method VERIFICATION equivalent response model
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Analysis of forest structural complexity using airborne LiDAR data and aerial photography in a mixed conifer–broadleaf forest in northern Japan 被引量:6
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作者 Sadeepa Jayathunga Toshiaki Owari Satoshi Tsuyuki 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第2期473-487,共15页
Determining forest structural complexity,i.e.,a measure of the number of different attributes of a forest and the relative abundance of each attribute,is important for forest management and conservation.In this study,... Determining forest structural complexity,i.e.,a measure of the number of different attributes of a forest and the relative abundance of each attribute,is important for forest management and conservation.In this study,we examined the structural complexity of mixed conifer–broadleaf forests by integrating multiple forest structural attributes derived from airborne Li DAR data and aerial photography.We sampled 76 plots from an unmanaged mixed conifer–broadleaf forest reserve in northern Japan.Plot-level metrics were computed for all plots using both field and remote sensing data to assess their ability to capture the vertical and horizontal variations of forest structure.A multivariate set of forest structural attributes that included three Li DAR metrics(95 th percentile canopy height,canopy density and surface area ratio) and one image metric(proportion of broadleaf cover),was used to classify forest structure into structural complexity classes.Our results revealed significant correlation between field and remote sensing metrics,indicating that these two sets of measurements captured similar patterns of structure in mixed conifer–broadleaf forests.Further,cluster analysis identified six forest structural complexity classes includingtwo low-complexity classes and four high-complexity classes that were distributed in different elevation ranges.In this study,we could reliably analyze the structural complexity of mixed conifer–broadleaf forests using a simple and easy to calculate set of forest structural attributes derived from airborne Li DAR data and high-resolution aerial photography.This study provides a good example of the use of airborne Li DAR data sets for wider purposes in forest ecology as well as in forest management. 展开更多
关键词 airborne laser scanning High resolution imagery HOKKAIDO Forest structure Pan-mixed forests
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Comprehensive characterization of indoor airborne bacterial profile 被引量:5
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作者 P. L. Chan P. H. F. Yu +2 位作者 Y. W. Cheng C. Y. Chan P. K. Wong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第8期1148-1152,共5页
This is the first detailed characterization of the airborne bacterial profiles in indoor environments. Two restaurants were selected for this study. Fifteen genera of bacteria were isolated from each restaurant and id... This is the first detailed characterization of the airborne bacterial profiles in indoor environments. Two restaurants were selected for this study. Fifteen genera of bacteria were isolated from each restaurant and identified by three different bacterial identification systems including MIDI, Biolog and Riboprinter. The dominant bacteria of both restaurants were Gram-positive bacteria in which Micrococcus and Bacillus species were the most abundant. Most bacteria identified were representative species of skin and respiratory tract of human, and soil. Although the bacterial levels in these two restaurants were below the limit of the Hong Kong Indoor Air Quality Objective (HKIAQO) Level 1 standard (i.e., 〈 500 cfu/m^3), the majority of these bacteria were opportunistic pathogens. These results suggested that the identity of airborne bacteria should also be included in the IAQ to ensure there is a safety guideline for the public. 展开更多
关键词 airborne bacterial profile bacterial identification indoor air quality
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Space-time clutter model for airborne bistatic radar with non-Gaussian statistics 被引量:4
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作者 Duan Rui Wang Xuegang Jiang Chaoshu Chen Zhuming 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期283-290,共8页
To validate the potential space-time adaptive processing (STAP) algorithms for airborne bistatic radar clutter suppression under nonstationary and non-Gaussian clutter environments, a statistically non-Gaussian, spa... To validate the potential space-time adaptive processing (STAP) algorithms for airborne bistatic radar clutter suppression under nonstationary and non-Gaussian clutter environments, a statistically non-Gaussian, space-time clutter model in varying bistatic geometrical scenarios is presented. The inclusive effects of the model contain the range dependency of bistatic clutter spectrum and clutter power variation in range-angle cells. To capture them, a new approach to coordinate system conversion is initiated into formulating bistatic geometrical model, and the bistatic non-Gaussian amplitude clutter representation method based on a compound model is introduced. The veracity of the geometrical model is validated by using the bistatic configuration parameters of multi-channel airborne radar measurement (MCARM) experiment. And simulation results manifest that the proposed model can accurately shape the space-time clutter spectrum tied up with specific airborne bistatic radar scenario and can characterize the heterogeneity of clutter amplitude distribution in practical clutter environments. 展开更多
关键词 airborne bistatic radar clutter model GEOMETRY NON-GAUSSIAN
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Study of Residual Basin and Tectonolayering Based on Airborne Gravity and Magnetic Data 被引量:6
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作者 LI Wenyong ZHOU Jianxin +2 位作者 XIONG Shengqing LIU Yanxu XU Jianchun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第4期1137-1153,共17页
This paper takes the South Yellow Sea as an example to show a new method for comprehensive geological-geophysical research such as residual basin and tectonolayering using airborne gravity and magnetic data in China. ... This paper takes the South Yellow Sea as an example to show a new method for comprehensive geological-geophysical research such as residual basin and tectonolayering using airborne gravity and magnetic data in China. Based on airborne gravity and magnetic data, by measuring and analyzing stratigraphic density and susceptibility, the depths to the pre-Sinian magnetic basement top, the pre-Jurassic top and the Cenozoic bottom, are obtained by forward and inverse methods constrained by seismic and drilling data; and furthermore, the residual thicknesses of the Sinian-Triassic, the Jurassic-Cretaceous and the Cenozoic are calculated. Based on airborne gravity and magnetic anomalies, the faults in the pre-Sinian magnetic basement, the Jurassic-Cretaceous and the Cenozoic are respectively interpreted by the qualitative and quantitative methods. On the basis of the above study, and combining regional important tectonic events, four tectonolayers are divided in the vertical succession in South Yellow Sea, namely the pre-Sinian magnetic basement, the Sinian-Triassic, the Jurassic-Cretaceous and the Cenozoic. The result shows that there are thick Cenozoic and Jurassic-Cretaceous strata and thin residual Sinian-Triassic strata in the Suzhong-Huangnan depression area, but there are thin or only sporadic Mesozoic-Cenozoic terrestrial strata and thick Sinian-Triassic marine strata reserved in Subei-Huangzhong uplift area and Sunan-Wunansha uplift area. The four tectonolayers are very different in structures as well as distributions in plane. 展开更多
关键词 airborne gravity and magnetics comprehensive interpretation residual basin tectonolayering South Yellow Sea
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Study on Size Distributions of Airborne Particles by Aircraft Observation in Spring over Eastern Coastal Areas of China 被引量:3
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作者 王玮 刘红杰 +3 位作者 岳欣 李红 陈建华 汤大钢 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第3期328-336,共9页
The authors studied the size distributions of particles at an altitude of 2000 m by aircraft observation over eastern costal areas of China from Zhuhai, Guangdong to Dalian, Liaoning (0.47-30 μm, 57 channels, includi... The authors studied the size distributions of particles at an altitude of 2000 m by aircraft observation over eastern costal areas of China from Zhuhai, Guangdong to Dalian, Liaoning (0.47-30 μm, 57 channels, including number concentration distribution, surface area concentration distribution and mass concentration distribution). In these cities, the average daily concentrations of PM10 are very high. They are among the most heavily polluted cities in China. The main pollution sources are anthropogenic activities such as wood, coal and oil burning. The observed size distributions show a broad spectrum and unique multi-peak characteristics, indicating no significant impacts of individual sources from urban areas. These results are far different from the distribution type at ground level. It may reflect the comprehensive effect of the regional pollution characteristics. Monitoring results over big cities could to some extent reflect their pollution characteristics. 展开更多
关键词 airborne particles size distribution aircraft observation coastal areas China
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