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Height connection across sea by using satellite altimetry data sets,ellipsoidal heights,astrogeodetic deflections of the vertical,and an Earth Gravity Model
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作者 Jianbo Wang Xinmin Qi +3 位作者 Kai Luo Zhengyuan Li Ruikang Zhou Jinyun Guo 《Geodesy and Geodynamics》 EI CSCD 2023年第4期347-354,共8页
Islands and the mainland are separated by seas,and the distances between them might be so long that the height on the mainland cannot be exactly translated to the islands,resulting in different height systems on the m... Islands and the mainland are separated by seas,and the distances between them might be so long that the height on the mainland cannot be exactly translated to the islands,resulting in different height systems on the mainland and the islands.In this study,we used astrogeodetic deflections of the vertical and ellipsoidal heights of points on the mainland and island near their coastlines to implement height connection across sea areas.First,the modeled gravity and modeled astrogeodetic vertical deflections of segmentation points along connecting routes over the sea between the mainland and the island were determined by Earth Gravity Model(EGM),and the ellipsoidal heights of segmentation points were determined by the satellite altimetry data sets.Second,we used a linear interpolation model to increase the precision of the vertical deflections of segmentation points.Third,we computed the geopotential difference of points between the mainland and the island using a method derived from geopotential theory and the astronomical leveling principle.Finally,we estimated the normal height of the point on the island using the geopotential-difference iterative computation approach.Using observed data of normal heights,ellipsoidal heights,and astrogeodetic vertical deflections referring to height sites in Qingdao,Shandong Province,we conducted a numerical experiment involving the normal height connection across sea regions.We determined the data of the ellipsoidal heights and gravity of segmentation points along the connecting route across the water in the numerical experiment using DTU10.The distance of the height connection across the sea was approximately 10.5 km.According to China's official leveling specifications,the experimental results met the criterion of third-class leveling precision. 展开更多
关键词 Height datum connection across sea areas Geopotential difference Normal heights Astrogeodetic vertical deflections ISLANDS
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Wake Effects on A Hybrid Semi-Submersible Floating Wind Farm with Multiple Hub Heights
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作者 XU Xiao-sen GU Jia-yang +5 位作者 LING Hong-jie YANG Pu-yi WANG Shuai-shuai XING Yi-han Oleg GAIDAI ZHANG Zhong-yu 《China Ocean Engineering》 SCIE EI CSCD 2023年第1期101-114,共14页
Wind farms generally consist of a single turbine installed with the same hub height. As the scale of turbines increases,wake interference between turbines becomes increasingly significant, especially for floating wind... Wind farms generally consist of a single turbine installed with the same hub height. As the scale of turbines increases,wake interference between turbines becomes increasingly significant, especially for floating wind turbines(FWT).Some researchers find that wind farms with multiple hub heights could increase the annual energy production(AEP),while previous studies also indicate that wake meandering could increase fatigue loading. This study investigates the wake interaction within a hybrid floating wind farm with multiple hub heights. In this study, FAST.Farm is employed to simulate a hybrid wind farm which consists of four semi-submersible FWTs(5MW and 15MW) with two different hub heights. Three typical wind speeds(below-rated, rated, and over-rated) are considered in this paper to investigate the wake meandering effects on the dynamics of two FWTs. Damage equivalent loads(DEL) of the turbine critical components are computed and analyzed for several arrangements determined by the different spacing of the four turbines. The result shows that the dynamic wake meandering significantly affects downstream turbines’ global loadings and load effects. Differences in DEL show that blade-root flapwise bending moments and mooring fairlead tensions are sensitive to the spacing of the turbines. 展开更多
关键词 hybrid floating wind farm wake meandering multiple hub heights floating wind turbine FAST.Farm fatigue
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Regularity classification and corresponding analysis method requirements of horizontally curved bridges with unequal pier heights 被引量:1
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作者 Mohammad Jalal Maleki-amin Shahrokh Maalek 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第2期549-571,共23页
The seismic behavior of horizontally curved bridges,particularly with unequal height piers,is more complicated than that of straight bridges due to their geometric properties.In this study,the seismic responses of sev... The seismic behavior of horizontally curved bridges,particularly with unequal height piers,is more complicated than that of straight bridges due to their geometric properties.In this study,the seismic responses of several horizontally curved single-column-bent viaducts with various degrees of curvature and different pier heights have been investigated,employing three different analysis approaches:namely,modal pushover analysis,uniform load method,and nonlinear time history analysis.Considering the investigated bridge configurations and utilizing the most common regularity indices,the results indicate that viaducts with 45-degree and 90-degree deck subtended angles can be categorized as regular and moderately irregular,respectively,while the bridges with 180-degree deck subtended angle are found to be highly irregular.Furthermore,the viaducts whose pier heights are asymmetric may be considered as irregular for almost all ranges of the deck subtended angles.The effects of higher transverse and longitudinal modes are discussed and the minimum analysis requirements are identified to assess the seismic response of such bridge configurations for design purposes.Although the Regularity Indices used here are useful tools to distinguish between regular and irregular bridges,further studies are needed to improve their reliability. 展开更多
关键词 horizontally curved bridges unequal height piers pushover analysis regularity index seismic analysis and response
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Joint Return Value Estimation of Significant Wave Heights and Wind Speeds with Bivariate Copulas
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作者 TAO Shanshan DONG Sheng +1 位作者 LIN Yifan GUEDES SOARES Carlos 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第5期1181-1192,共12页
The joint design criteria of significant wave heights and wind speeds are quite important for the structural reliability of fixed offshore platforms.However,the design method that regards different ocean environmental... The joint design criteria of significant wave heights and wind speeds are quite important for the structural reliability of fixed offshore platforms.However,the design method that regards different ocean environmental variables as independent is conservative.In the present study,we introduce a bivariate sample consisting of the maximum wave heights and concomitant wind speeds of the threshold by using the peak-over-threshold and declustering methods.After selecting the appropriate bivariate copulas and univariate distributions and blocking the sample into years,the bivariate compound distribution of annual extreme wave heights and concomitant wind speeds is constructed.Two joint design criteria,namely,the joint probability density method and the conditional probability method,are applied to obtain the joint return values of significant wave heights and wind speeds.Results show that(28.5±0.5)m s^(-1)is the frequently obtained wind speed based on the Atlantic dataset,and these joint design values are more appropriate than those calculated by univariate analysis in the fatigue design. 展开更多
关键词 joint design wave height wind speed compound distribution COPULA
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Exploration to the writing techniques of Wuthering Heights
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作者 王珊珊 《海外英语》 2014年第4X期184-185,共2页
Wuthering Heights has been one of the most famous novels in English literature. Emily's writing skills are worth the exploration. She can successfully handle the events out of chronological order; she can master t... Wuthering Heights has been one of the most famous novels in English literature. Emily's writing skills are worth the exploration. She can successfully handle the events out of chronological order; she can master the multiple narrator technique; she can create such repetitions of plots and she can design many meaningful symbols. No wonder why Wuthering Heights is in the a high position in the world literature. 展开更多
关键词 Wuthering heights WRITING TECHNIQUES EMILY Brontё
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An Analysis of Catherine’s Tragedy at Wuthering Heights—from the Contradiction between“Id”and“Social Reality” 被引量:11
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作者 薛明府 王富银 《海外英语》 2019年第16期235-237,共3页
There exist discussions about the heroine's love tragedy in Wuthering Heights from time to time.Based on Freud's Id theory as the starting point,it serves as a new viewpoint of review focusing on the conflict ... There exist discussions about the heroine's love tragedy in Wuthering Heights from time to time.Based on Freud's Id theory as the starting point,it serves as a new viewpoint of review focusing on the conflict between“Social Reality”and“Id”in the novel to analyse the causes of Catherine's love tragedy and criticize the devastation of humanity brought by the concept of“money first”and“family hierarchy”in the 19th century capitalist society. 展开更多
关键词 Wuthering heights ID Catherine's TRAGEDY
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Application of Maximum Entropy Principle to Studying the Distribution of Wave Heights in A Random Wave Field 被引量:6
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作者 周良明 郭佩芳 +1 位作者 王强 杜伊 《海洋工程:英文版》 EI 2004年第1期69-78,共10页
Based on the maximum entropy principle, a probability density function (PDF) is derived for the distribution of wave heights in a random wave field, without any more hypothesis. The present PDF, being a non-Rayleigh f... Based on the maximum entropy principle, a probability density function (PDF) is derived for the distribution of wave heights in a random wave field, without any more hypothesis. The present PDF, being a non-Rayleigh form, involves two parameters: the average wave height H— and the state parameter γ. The role of γ in the distribution of wave heights is examined. It is found that γ may be a certain measure of sea state. A least square method for determining γ from measured data is proposed. In virtue of the method, the values of γ are determined for three sea states from the data measured in the East China Sea. The present PDF is compared with the well known Rayleigh PDF of wave height and it is shown that it much better fits the data than the Rayleigh PDF. It is expected that the present PDF would fit some other wave variables, since its derivation is not restricted only to the wave height. 展开更多
关键词 information entropy wave heights maximum entropy probability density function Rayleigh distribution
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A Maximum-Entropy Compound Distribution Model for Extreme Wave Heights of Typhoon-Affected Sea Areas 被引量:4
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作者 王莉萍 孙效光 +1 位作者 吕可波 徐德伦 《China Ocean Engineering》 SCIE EI 2012年第1期49-58,共10页
A new compound distribution model for extreme wave heights of typhoon-affected sea areas is proposed on the basis of the maximum-entropy principle. The new model is formed by nesting a discrete distribution in a conti... A new compound distribution model for extreme wave heights of typhoon-affected sea areas is proposed on the basis of the maximum-entropy principle. The new model is formed by nesting a discrete distribution in a continuous one, having eight parameters which can be determined in terms of observed data of typhoon occurrence-frequency and extreme wave heights by numerically solving two sets of equations derived in this paper. The model is examined by using it to predict the N-year return-period wave height at two hydrology stations in the Yellow Sea, and the predicted results are compared with those predicted by use of some other compound distribution models. Examinations and comparisons show that the model has some advantages for predicting the N-year return-period wave height in typhoon-affected sea areas. 展开更多
关键词 maximum entropy principle typhoon occurrence-frequency N-year return period wave heights maximumentropy compound distribution
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Fabrication of High-Density Out-of-Plane Microneedle Arrays with Various Heights and Diverse Cross-Sectional Shapes 被引量:2
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作者 Hyeonhee Roh Young Jun Yoon +4 位作者 Jin Soo Park Dong-Hyun Kang Seung Min Kwak Byung Chul Lee Maesoon Im 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第2期60-78,共19页
Out-of-plane microneedle structures are widely used in various applications such as transcutaneous drug delivery and neural signal recording for brain machine interface.This work presents a novel but simple method to ... Out-of-plane microneedle structures are widely used in various applications such as transcutaneous drug delivery and neural signal recording for brain machine interface.This work presents a novel but simple method to fabricate high-density silicon(Si)microneedle arrays with various heights and diverse cross-sectional shapes depending on photomask pattern designs.The proposed fabrication method is composed of a single photolithography and two subsequent deep reactive ion etching(DRIE)steps.First,a photoresist layer was patterned on a Si substrate to define areas to be etched,which will eventually determine the final location and shape of each individual microneedle.Then,the 1st DRIE step created deep trenches with a highly anisotropic etching of the Si substrate.Subsequently,the photoresist was removed for more isotropic etching;the 2nd DRIE isolated and sharpened microneedles from the predefined trench structures.Depending on diverse photomask designs,the 2nd DRIE formed arrays of microneedles that have various height distributions,as well as diverse cross-sectional shapes across the substrate.With these simple steps,high-aspect ratio microneedles were created in the high density of up to 625 microneedles mm^(-2)on a Si wafer.Insertion tests showed a small force as low as~172μN/microneedle is required for microneedle arrays to penetrate the dura mater of a mouse brain.To demonstrate a feasibility of drug delivery application,we also implemented silk microneedle arrays using molding processes.The fabrication method of the present study is expected to be broadly applicable to create microneedle structures for drug delivery,neuroprosthetic devices,and so on. 展开更多
关键词 MICRONEEDLE Various heights Cross-sectional shapes Isotropic etch Deep reactive ion etching
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Stochastic seismic response of multi-layered soil with random layer heights 被引量:1
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作者 M.Badaoui M.K.Berrah A.Mébarki 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2010年第2期213-221,共9页
This paper deals with the effect of layer height randomness on the seismic response of a layered soil. These parameters are assumed to be lognormal random variables. The analysis is carried out via Monte Carlo simulat... This paper deals with the effect of layer height randomness on the seismic response of a layered soil. These parameters are assumed to be lognormal random variables. The analysis is carried out via Monte Carlo simulations coupled with the stiffness matrix method. A parametric study is conducted to derive the stochastic behavior of the peak ground acceleration and its response spectrum,the transfer function and the amplification factors. The input soil characteristics correspond to a site in Mexico City and the input seismic accelerations correspond to the Loma Prieta earthquake. It is found that the layer height heterogeneity causes a widening of the frequency content and a slight increase in the fundamental frequency of the soil profile,indicating that the resonance phenomenon is a concern for a large number of structures. Variation of the layer height randomness acts as a variation of the incident angle,i.e.,a decrease of the amplitude and a shift of the resonant frequencies. 展开更多
关键词 random layer heights layered soil seismic acceleration lognormal distribution amplification factors Mexico City
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Nelly the Greatest Villain in Wuthering Heights
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作者 王静 张景玲 《海外英语》 2017年第24期168-169,179,共3页
Nelly in Wuthering Heights is viewed by many critics as a servant who witnesses the love-hatred story of the two generations, an onlooker and narrator who seems calmly detached from the story, a friend-like figure of ... Nelly in Wuthering Heights is viewed by many critics as a servant who witnesses the love-hatred story of the two generations, an onlooker and narrator who seems calmly detached from the story, a friend-like figure of honesty, fidelity and benevolence. However a close reading of the novel reveals that the role of Nelly is more than that. Nelly not only is deeply involved in the story, but also plays the very important role of the representative of the malicious adult, the great villain who contributes much to the development of the story. 展开更多
关键词 Wuthering heights Nelly CHILD ADULT VILLAIN
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An Analysis of Heathcliff's Silence in Wuthering Heights
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作者 潘琛 《海外英语》 2013年第17期191-194,236,共5页
Heathcliff is a highly controversial character in Emily Bront 's canon Wuthering Heights. He is depicted as an incredi ble conglomeration of enigmas and simplicity, aloofness and affinity, ferocity and vulnerabili... Heathcliff is a highly controversial character in Emily Bront 's canon Wuthering Heights. He is depicted as an incredi ble conglomeration of enigmas and simplicity, aloofness and affinity, ferocity and vulnerability, inhumanity and heroicity, a man who appears more silent and preoccupied than talkative and carefree, inaudible and incalculable in both words and thoughts. The author of this paper considers that there is much left to be read and contemplate on in Heathcliff's silence and thus make a tempa tive research into Heathcliff's silence by discerning its manifestations and probing its causes, in order to resonate with the inner touch of this complicated soul and relate his silence with the spirit that Emily Bront wished to deliver through Wuthering Heights. Heathcliff's silence manifests as muteness, elusion and colloquial or physical violence. In his whole life, Heathcliff inter mittently experiences the self-chosen silence and the forced silence. He chooses to be silence out of self-protection and the infe riority complex; he considers silence as a token of masculinity. And the ruthless force from outside also compels him into a periph eralized situation where he has to keep silent and struggles against the torture and torment alone. 展开更多
关键词 HEATHCLIFF SILENCE Wurhering heights NATURE and LO
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A New Interpretation on the Theme of Wuthering Heights
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作者 杨美君 《海外英语》 2011年第9X期377-378,共2页
In Wuthering Heights,Heathcliff and Hareton are technically enemies but they share many similarities,such as their growing environment,feeling of inferiority complex,and their intensive persistence in love for their b... In Wuthering Heights,Heathcliff and Hareton are technically enemies but they share many similarities,such as their growing environment,feeling of inferiority complex,and their intensive persistence in love for their beloved.The major difference between them is the attitude towards revenge and tolerance.Depicting the similarity and difference between the two characters that starts with the same fate but ends with completely different consequence,Emily Bronte indicates the karma that avenger will suffer from the evil consequence committed by himself and tolerance is the true virtue. 展开更多
关键词 wuthering heights HEATHCLIFF hareton comparison KARMA
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On the Tragic Love in Emily Bronte's Wuthering Heights 被引量:1
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作者 李俊华 《海外英语》 2014年第24期180-181,共2页
Wuthering Heights is a highly imaginative novel of love and revenge and a shining pearl in the treasure of English literature.This thesis aims to make a full exploration of the inner and external reasons resulting in ... Wuthering Heights is a highly imaginative novel of love and revenge and a shining pearl in the treasure of English literature.This thesis aims to make a full exploration of the inner and external reasons resulting in the tragic love between Catherine and Heathcliff in the novel with the application of Freud’s theory of personality structure and from metaphorically geographical,social and economic perspectives as well.Readers are expected to fully realize the destructive force of a desperate soul,better appreciate the tragic beauty of a doomed love and,above all,capture the humane light beneath a tragic drama. 展开更多
关键词 Wuthering heights TRAGIC LOVE Freud’s THEORY of PE
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On the Narrative Unreliability in Wuthering Heights
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作者 陈敏 《海外英语》 2011年第6X期233-234,共2页
Since its publication, Wuthering Heights has won great popularity home and abroad for the complexity and delicacy of the narration. However, the story is not true as the unreliability of its narrator is obvious as far... Since its publication, Wuthering Heights has won great popularity home and abroad for the complexity and delicacy of the narration. However, the story is not true as the unreliability of its narrator is obvious as far as it is judged by Rimmon-Kenan's theory of narrative unreliability. 展开更多
关键词 NARRATIVE UNRELIABILITY Wuthering heights Rimrnon-Kenan
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CALCULATIONS OF WAVE BREAKING PROBABILITY AND DISTRIBUTION OF BREAKING WAVE HEIGHTS IN DEEP WATER
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作者 宋金宝 娄顺里 田纪伟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1997年第3期252-257,共6页
This practical method for calculating the probability of a wave breaking and the distribution of breaking weve heights is based on the joint probebility distribution of wave heights and periods derived by Sun Fu and t... This practical method for calculating the probability of a wave breaking and the distribution of breaking weve heights is based on the joint probebility distribution of wave heights and periods derived by Sun Fu and the breaking criterion obtained by Ochi and Tsai from measurements of irregular waves generated in a tank. Computations for differnt an states using the P-M spectrum and the JONSWAP spectrum showed that the probability of wave basking (or the distribution of beding were heights) in the deep ocean can be determined, at least approximated, from the zero, the first and the scond moments of the wave spectrum. 展开更多
关键词 WAVE BREAKING PROBABILITY of WAVE BREAKING DISTRIBUTION of BREAKING WAVE heights
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Long-Period Distribution of Wave Heights and Its Application
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作者 Weng Keqin Associate Professor, Hydraulic and Hydro-Power Engineering Dept., Tsinghua University, Beijing 100084 《China Ocean Engineering》 SCIE EI 1995年第2期171-182,共12页
This paper reveals that the long-period statistic distribution of the characteristic heights of deep-water waves assumes the lognormal distribution. Thereafter, the largest wave-height which may occur in the service l... This paper reveals that the long-period statistic distribution of the characteristic heights of deep-water waves assumes the lognormal distribution. Thereafter, the largest wave-height which may occur in the service life of coastal structures is derived in this paper. 展开更多
关键词 WAVE distribution of wave heights extreme wave height APPLICATION
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Regional Frequency Analysis of Significant Wave Heights Based onL-moments
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作者 马青山 李炎保 李静 《China Ocean Engineering》 SCIE EI 2006年第1期85-98,共14页
L-moments are defined as linear combinations of probability-weighted moments, They are, virtually unbiased for small samples, and perform well in parameter estimation, choice of the distribution type and regional anal... L-moments are defined as linear combinations of probability-weighted moments, They are, virtually unbiased for small samples, and perform well in parameter estimation, choice of the distribution type and regional analysis. The traditional methods of determining the design wave heights for planning marine structures use data only from the site of interest. Regional frequency analysis gives a new approach to estimate quantile by use of the homogeneous neighborhood informatian. A regional frequency analysis based on L-moments with a case study of the California coast is presented. The significant wave height data for the California coast is offered by NDBC. A 6-site region without 46023 is considered to be a homogeneous region, whose optimal regional distribution is Pearson Ⅲ. The test is conducted by a simulation process. The regional quantile is compared with the at-site quantile, and it is shown that efficient neighborhood information can be used via regional frequency analysis to give a reasonable estimation of the site without enough historical data. 展开更多
关键词 L-MOMENTS regional frequency analysis significant wave heights SIMULATION
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Influence of shallow low resistivity thin layer on SATEM response at different receiving heights in near and far regions
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作者 Shixing Wang Ming Guo +1 位作者 Zhenxiong Zhang Guocai Yi 《Earthquake Research Advances》 CSCD 2021年第S01期38-40,共3页
In recent years,the semi-airborne transient electromagnetic method(SATEM)has been rapidly developed in China.Based on the theoretical development of the long grounding wire source transient electromagnetic method,the ... In recent years,the semi-airborne transient electromagnetic method(SATEM)has been rapidly developed in China.Based on the theoretical development of the long grounding wire source transient electromagnetic method,the unmanned aerial vehicle is equipped with the receiving coil to collect the electromagnetic response data at high altitude,making the TEM no longer affected by the terrain and greatly improving the actual working efficiency.However,its flight altitude has not been concerned for a long time.It is generally believed that the change of flight altitude only affects the amplitude of the received response.However,under special circumstances,the electromagnetic response data received at different flight altitudes in the near and far regions may lose the characteristic information of the target geological body.This paper simulates the low resistance thin layer model and analyzes the electromagnetic responses of different receiving heights under different transceiver distances.The results show that in the near area,when the flight altitude is higher than 30 meters or more,the received electromagnetic response will lose the information of the shallow lowresistance thin layer,while in the far area,the change of flight altitude has no obvious influence on the characteristic electromagnetic response information of the received geological body. 展开更多
关键词 Semi-airborne transient electomagnetic method SHALLOW low RESISTIVITY thin layer receiving heights
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A Possible Relationship between Schottky Barrier Heights and Adhesion Energies of Metal/Semiconductor or
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作者 李建国 《Rare Metals》 SCIE EI CAS CSCD 1994年第1期7-12,共6页
A possible relationship between Schottky barrier heights and adhesion energies of different nonreactivemetal/semiconductor or insulator interfaces is presented .Various experimental evidences further sup-porting such ... A possible relationship between Schottky barrier heights and adhesion energies of different nonreactivemetal/semiconductor or insulator interfaces is presented .Various experimental evidences further sup-porting such a relationship are briefly exploited. The consequence indicated by such a relationship on the understanding of metal / ceramic interfaces is stressed. 展开更多
关键词 Schottky barrier heights Adhesion energies Metal/ semiconductorinterfaces
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