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基于层次分析法确定复合成本计算模式的“元”数
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作者 陈祯剑 杨攀 《北方经贸》 2007年第12期72-73,共2页
兼顾成本计算模式的实用性和经济性,复合成本计算模式"元"数确定应遵循算为管用原则。复合成本计算对象原则,经济可行原则;通过建立"元"数的确定评价指标,采用层次分析法对复合成本计算模式进行"元"数的... 兼顾成本计算模式的实用性和经济性,复合成本计算模式"元"数确定应遵循算为管用原则。复合成本计算对象原则,经济可行原则;通过建立"元"数的确定评价指标,采用层次分析法对复合成本计算模式进行"元"数的选择。 展开更多
关键词 成本计算模式 “元”数 层次分析法
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A holographic optical communication system based on RSA algorithm and quaternion function
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作者 YANG Peng HAN Jianning 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期338-343,共6页
A facile encryption way was successfully applied to the holographic optical encryption system with high speed,multidimensionality,and high capacity,which provided a better security solution for underwater communicatio... A facile encryption way was successfully applied to the holographic optical encryption system with high speed,multidimensionality,and high capacity,which provided a better security solution for underwater communication.The reconstructed optical security system for information transmission was based on wavelengthλand focal length f that were keys to encryption and decryption.To finish the secure data transmission(λ,f)between sender and receiver,an extended Rivest-Shamir-Adleman(ERSA)algorithm for the encryption was achieved based on three-dimension quaternion function.Therein,the Pollard’s rho method was used for the evaluation and comparison of RSA and ERSA algorithms.The results demonstrate that the message encrypted by the ERSA algorithm has better security than that by RSA algorithm in the face of unpredictability and complexity of information transmission on the unsecure acoustic channel. 展开更多
关键词 HOLOGRAPHY QUATERNION Fourier lens extended Rivest-Shamir-Adleman(ERSA) Pollard’s rho method
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A novel method for integrating chromatographic fingerprint analytical units of Chinese materia medica:the matching frequency statistical moment method
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作者 LI Haiying PAN Xue +4 位作者 WANG Mincun LI Wenjiao HE Peng HUANG Sheng HE Fuyuan 《Digital Chinese Medicine》 CAS CSCD 2024年第3期294-308,共15页
Objective To facilitate the quality evaluation suitable for the unique characteristics of Chinese materia medica(CMM)by developing and implementing a novel approach known as the matching frequency statistical moment(M... Objective To facilitate the quality evaluation suitable for the unique characteristics of Chinese materia medica(CMM)by developing and implementing a novel approach known as the matching frequency statistical moment(MFSM)method.Methods This study established the MFSM method.To demonstrate its effectiveness,we applied this novel approach to analyze Danxi Granules(丹膝颗粒,DXG)and its constituent herbal materials.To begin with,the ultra-performance liquid chromatography(UPLC)was applied to obtain the chromatographic fingerprints of DXG and its constituent herbal materi-als.Next,the MFSM was leveraged to compress and integrate them into a new fingerprint with fewer analytical units.Then,we characterized the properties and variability of both the original and integrated fingerprints by calculating total quantum statistical moment(TQSM)parameters,information entropy and information amount,along with their relative standard deviation(RSD).Finally,we compared the TQSM parameters,information entropy and infor-mation amount,and their RSD between the traditional and novel fingerprints to validate the new analytical method.Results The chromatographic peaks of DXG and its 12 raw herbal materials were divided and integrated into peak families by the MFSM method.Before integration,the ranges of the peak number,three TQSM parameters,information entropy and information amount for each peak or peak family of UPLC fingerprints of DXG and its 12 raw herbal materials were 95.07−209.73,9390−183064μv·s,5.928−21.33 min,22.62−106.69 min^(2),4.230−6.539,and 50530−974186μv·s,respectively.After integration,the ranges of these parameters were 10.00−88.00,9390−183064μv·s,5.951−22.02 min,22.27−104.73 min^(2),2.223−5.277,and 38159−807200μv·s,respectively.Correspondingly,the RSD of all the aforementioned pa-rameters before integration were 2.12%−9.15%,6.04%−49.78%,1.15%−23.10%,3.97%−25.79%,1.49%−19.86%,and 6.64%−51.20%,respectively.However,after integration,they changed to 0.00%,6.04%−49.87%,1.73%−23.02%,3.84%−26.85%,1.17%−16.54%,and 6.40%−48.59%,respectively.The results demonstrated that in the newly integrated fingerprint,the analytical units of constituent herbal materials,information entropy and information amount were significantly reduced(P<0.05),while the TQSM parameters remained unchanged(P>0.05).Additionally,the RSD of the TQSM parameters,information entropy,and information amount didn’t show significant difference before and after integration(P>0.05),but the RSD of the number and area of the integrated analytical units significantly decreased(P<0.05).Conclusion The MFSM method could reduce the analytical units of constituent herbal mate-rials while maintain the properties and variability from their original fingerprint.Thus,it could serve as a feasible and reliable tool to reduce difficulties in analyzing multi-compo-nents within CMMs and facilitating the evaluation of their quality. 展开更多
关键词 Chromatographic fingerprints Analytical units Matching frequency statistical moment method Chinese materia medica Danxi Granule(丹膝颗粒 DXG) Quality evaluation
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Computation of elastic properties of 3D digital cores from the Longmaxi shale 被引量:5
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作者 张文辉 符力耘 +1 位作者 张艳 金维浚 《Applied Geophysics》 SCIE CSCD 2016年第2期364-374,420,共12页
The dependence of elastic moduli of shales on the mineralogy and microstructure of shales is important for the prediction of sweet spots and shale gas production. Based on 3D digital images of the microstructure of Lo... The dependence of elastic moduli of shales on the mineralogy and microstructure of shales is important for the prediction of sweet spots and shale gas production. Based on 3D digital images of the microstructure of Longmaxi black shale samples using X-ray CT, we built detailed 3D digital images of cores with porosity properties and mineral contents. Next, we used finite-element (FE) methods to derive the elastic properties of the samples. The FE method can accurately model the shale mineralogy. Particular attention is paid to the derived elastic properties and their dependence on porosity and kerogen. The elastic moduli generally decrease with increasing porosity and kerogen, and there is a critical porosity (0.75) and kerogen content (ca. ≤3%) over which the elastic moduli decrease rapidly and slowly, respectively. The derived elastic moduli of gas- and oil-saturated digital cores differ little probably because of the low porosity (4.5%) of the Longmaxi black shale. Clearly, the numerical experiments demonstrated the feasibility of combining microstructure images of shale samples with elastic moduli calculations to predict shale properties. 展开更多
关键词 Longmaxi black shale 3D digital cores elastic properties finite-element method
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Ontology and metadata for online learning resource repository management based on semantic web 被引量:3
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作者 宋华珠 钟珞 +1 位作者 王辉 李锐弢 《Journal of Southeast University(English Edition)》 EI CAS 2006年第3期399-403,共5页
An ontology and metadata for online learning resource repository management is constructed. First, based on the analysis of the use-case diagram, the upper ontology is illustrated which includes resource library ontol... An ontology and metadata for online learning resource repository management is constructed. First, based on the analysis of the use-case diagram, the upper ontology is illustrated which includes resource library ontology and user ontology, and evaluated from its function and implementation; then the corresponding class diagram, resource description framework (RDF) schema and extensible markup language (XML) schema are given. Secondly, the metadata for online learning resource repository management is proposed based on the Dublin Core Metadata Initiative and the IEEE Learning Technologies Standards Committee Learning Object Metadata Working Group. Finally, the inference instance is shown, which proves the validity of ontology and metadata in online learning resource repository management. 展开更多
关键词 semantic web online learning resource repository management(OLRRM) ONTOLOGY METADATA
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Analysis of deformation characteristic in multi-way loading forming process of aluminum alloy cross valve based on finite element model 被引量:5
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作者 张大伟 赵升吨 杨合 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第1期199-207,共9页
The deformation characteristic in the forming process of aluminum alloy 7075 cross valve under multi-way loading was investigated by numerical simulation method. The results indicate that there exist 4 deformation pat... The deformation characteristic in the forming process of aluminum alloy 7075 cross valve under multi-way loading was investigated by numerical simulation method. The results indicate that there exist 4 deformation patterns in the multi-way loading forming process of cross valve, such as forward extrusion, backward extrusion, forward-lateral extrusion and backward-lateral extrusion; one or several patterns occur at different forming stages depending on loading path. In general, the main deformation pattern is forward extrusion or backward extrusion at the initial stage; the main deformation pattern is backward extrusion at the intermediate stage, and the backward extrusion and forward-lateral extrusion occur at the final stage. In order to improve the cavity fill and reduce the forming defects, the lateral extrusion deformation should be increased at the initial and intermediate stages, and the forward extrusion deformation at the final forging stage should be reduced or avoided. 展开更多
关键词 cross valve multi-way loading deformation behavior metal flow aluminum alloy FEM numerical simulation
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Mixed noise removal for color images using quaternion representation 被引量:2
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作者 王定成 田宇航 +1 位作者 陈北京 舒华忠 《Journal of Southeast University(English Edition)》 EI CAS 2015年第3期347-352,共6页
In order to effectively restore color noisy images with the mixture of Gaussian noise and impulse noise,a new algorithm is proposed using the quaternion-based holistic processing idea for color images.First,a color im... In order to effectively restore color noisy images with the mixture of Gaussian noise and impulse noise,a new algorithm is proposed using the quaternion-based holistic processing idea for color images.First,a color image is represented by a pure quaternion matrix.Secondly,according to the different characteristics of the Gaussian noise and the impulse noise,an algorithm based on quaternion directional vector order statistics is used to detect the impulse noise. Finally,the quaternion optimal weights non-local means filter (QOWNLMF)for Gaussian noise removal is improved for the mixed noise removal.The detected impulse noise pixels are not considered in the calculation of weights.Experimental results on five standard images demonstrate that the proposed algorithm performs better than the commonly used robust outlyingness ratio-nonlocal means (ROR-NLM)algorithm and the optimal weights mixed filter (OWMF). 展开更多
关键词 color image denoising Gaussian noise impulse noise mixed noise QUATERNION
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Information Description of Vegetable Planting Metadata Model 被引量:1
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作者 陈宏 赵健 +2 位作者 池美香 邱荣洲 翁启勇 《Agricultural Science & Technology》 CAS 2012年第1期238-241,共4页
[Objective] To study the information description of vegetable planting metadata model. [Method] On the basis of analyzing the data involved in every as- pect of vegetable planting, this paper put forward description s... [Objective] To study the information description of vegetable planting metadata model. [Method] On the basis of analyzing the data involved in every as- pect of vegetable planting, this paper put forward description schemes of vegetable planting metadata and constructed vegetable planting metadata model by the means of XML/XML schema. [Result] Metadata model of vegetable planting was established, and information description of vegetable planting metadata model was realized by the using of XML Schema. The whole metadata model consists of 7 first-class classifica- tions, including more than 800 information description points which could completely record vegetable planting-related information. [Conclusion] Standards for data collec- tion, management and sharing were provided for the agriculture applications in indus- tries like GAP management of vegetable planting, facility vegetable, food quality traceability, etc. 展开更多
关键词 Vegetable planting XML/XML Schema METADATA
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Perfectly matched layer-absorbing boundary condition for finite-element time-domain modeling of elastic wave equations 被引量:3
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作者 赵建国 史瑞其 《Applied Geophysics》 SCIE CSCD 2013年第3期323-336,359,共15页
The perfectly matched layer (PML) is a highly efficient absorbing boundary condition used for the numerical modeling of seismic wave equation. The article focuses on the application of this technique to finite-eleme... The perfectly matched layer (PML) is a highly efficient absorbing boundary condition used for the numerical modeling of seismic wave equation. The article focuses on the application of this technique to finite-element time-domain numerical modeling of elastic wave equation. However, the finite-element time-domain scheme is based on the second- order wave equation in displacement formulation. Thus, the first-order PML in velocity-stress formulation cannot be directly applied to this scheme. In this article, we derive the finite- element matrix equations of second-order PML in displacement formulation, and accomplish the implementation of PML in finite-element time-domain modeling of elastic wave equation. The PML has an approximate zero reflection coefficients for bulk and surface waves in the finite-element modeling of P-SV and SH wave propagation in the 2D homogeneous elastic media. The numerical experiments using a two-layer model with irregular topography validate the efficiency of PML in the modeling of seismic wave propagation in geological models with complex structures and heterogeneous media. 展开更多
关键词 Absorbing boundary condition elastic wave equation perfectly matched layer finite-element modeling
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DUAL QUATERNION CURVE INTERPOLATION ALGORITHM FOR FORMATION SATELLITES 被引量:1
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作者 李静 王惠南 刘海颖 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第1期90-95,共6页
The traditional algorithms for formation flying satellites treat the satellite position and attitude sepa- rately. A novel algorithm combining satellite attitude with position is proposed. The principal satellite traj... The traditional algorithms for formation flying satellites treat the satellite position and attitude sepa- rately. A novel algorithm combining satellite attitude with position is proposed. The principal satellite trajectory is obtained by dual quaternion interpolation, then the relative position and attitude of the deputy satellite are ob- tained by dual quaternion modeling on the principal satellite. Through above process, relative position and atti- tude are unified. Compared with the orbital parameter and the quaternion methods, the simulation result proves that the algorithm can unify position and attitude, and satisfy the precision requirement of formation flying satel- lites. 展开更多
关键词 formation satellites dual quaternion interpolation algorithm relative position and attitude
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Analysis of the Elastic-Plastic Dynamic Finite Element on a Jointed Rock Mass 被引量:1
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作者 郭文章 冯顺山 王海福 《Journal of Beijing Institute of Technology》 EI CAS 1999年第2期27-32,共6页
Aim To study the elastic plastic dynamical constitutive relations about a jointed rock mass under explosion load and its computer simulation. Methods\ Stress history is taken into account and stresses will follow ch... Aim To study the elastic plastic dynamical constitutive relations about a jointed rock mass under explosion load and its computer simulation. Methods\ Stress history is taken into account and stresses will follow changes in time during a period of explosion load. According to the principle of static force balance, the corresponding nodal concentrated force is calculated and the nodal displacement is counted. The elastic plastic dynamic finite element equations are thus obtained. Results\ A finite element method is given for a jointed rock mass under explosion load. Conclusion\ The problem of large plastic deformation for jointed rock mass on blasting was efficiently resolved through dynamic finite element analysis and the range of damages by blasting simulated, and this pushes forward the problem to engineering practice. 展开更多
关键词 jointed rock mass dynamic finite element numerical simulation
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FAULT-TOLERANT INTEGRATED NAVIGATION SYSTEM BASED ON NEURONS 被引量:1
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作者 马昕 袁信 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1998年第2期4-7,共4页
In this paper, the multisensor data fusion technique of a fault tolerant integrated navigation system is discussed. A neural approach for data fusion is proposed for multisensor integrated systems. The simulation res... In this paper, the multisensor data fusion technique of a fault tolerant integrated navigation system is discussed. A neural approach for data fusion is proposed for multisensor integrated systems. The simulation results show that this neural approach for data fusion is feasible. 展开更多
关键词 navigation system NEURON data fusion fault tolerant
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On Triangle Interpolation Approximation of the Double Function 被引量:3
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作者 袁学刚 韩友发 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第4期61-65,共5页
本文以两组不同的节点构造了一个组合型的二元三角插值多项式算子Lmn(f;x,y),并且研究了二元连续周期函数对这个算子的收敛性及收敛阶的估计等问题。
关键词 double triangle interpolation polymial convergence order converge uniforml?
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Linear Factorization of λ _polynomial Over Quaternionic Field 被引量:3
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作者 郭时光 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期12-16,共5页
A proof is given that any λ _polynome over real quaternionic sfield can be factorized into produce of some linear factors.By the way,some properties and applications of this factorization in matrix theory are given.
关键词 determine polynome main spectral sequence main value SINGULAR
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IMPROVED ALGORITHM FOR CFD/CSD COUPLED SYSTEM DESIGN AND CALCULATION 被引量:4
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作者 安效民 徐敏 陈士橹 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第2期162-169,共8页
The data information transfer and time marching strategies between computational fluid dynamics (CFD) and computational structural dynamics (CSD) play crucial roles on the aeroelastic analysis in a time domain. An... The data information transfer and time marching strategies between computational fluid dynamics (CFD) and computational structural dynamics (CSD) play crucial roles on the aeroelastic analysis in a time domain. An improved CFD/CSD coupled system is designed, including an interpolation method and an improved loosely coupled algorithm. The interpolation method based on boundary element method (BEM) is developed to transfer aerodynamic loads and structural displacements between CFD and CSD grid systems, it can be universally used in fluid structural interaction solution by keeping energy conservation. The improved loosely coupled algo-rithm is designed, thus it improves the computational accuracy and efficiency. The new interface is performed on the two-dimensional (2-D) extrapolation and the aeroelastie response of AGARD445.6 wing. Results show that the improved interface has a superior accuracy. 展开更多
关键词 computational fluid dynamics boundary element method data transfer fluid and structure interaction aeroelasticity
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Effect of geometrical parameters on forming quality of high-strength TA18 titanium alloy tube in numerical control bending 被引量:7
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作者 方军 梁闯 +1 位作者 鲁世强 王克鲁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第2期309-318,共10页
The forming quality of high-strength TA18 titanium alloy tube during numerical control bending in changing bending angle β, relative bending radius R/D and tube sizes such as diameter D and wall thickness t was clari... The forming quality of high-strength TA18 titanium alloy tube during numerical control bending in changing bending angle β, relative bending radius R/D and tube sizes such as diameter D and wall thickness t was clarified by finite element simulation. The results show that the distribution of wall thickness change ratio Δt and cross section deformation ratio ΔD are very similar under different β; the Δt and ΔD decrease with the increase of R/D, and to obtain the qualified bent tube, the R/D must be greater than 2.0; the wall thinning ratio Δto slightly increases with larger D and t, while the wall thickening ratio Δti and ΔD increase with the larger D and smaller t; the Δto and ΔD firstly decrease and then increase, while the Δti increases, for the same D/t with the increase of D and t. 展开更多
关键词 high-strength TA18 tube geometrical parameters forming quality finite element simulation numerical control bending
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The Monotonicity Problems for Generalized Inverses of Matrices in H (n, ≥) 被引量:1
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作者 庄瓦金 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第3期18-23,共6页
On the basis of the paoers[3—7],this paper study the monotonicity problems for the positive semidefinite generalized inverses of the positive semidefinite self-conjugate matrices of quaternions in the Lowner partial ... On the basis of the paoers[3—7],this paper study the monotonicity problems for the positive semidefinite generalized inverses of the positive semidefinite self-conjugate matrices of quaternions in the Lowner partial order,give the explicit formulations of the monotonicity solution sets A{1;≥,T_1;≤B^(1)}and B{1;≥,T_2≥A^(1)}for the(1)-inverse,and two results of the monotonicity charac teriaztion for the(1,2)-inverse. 展开更多
关键词 positive semidefinite self-Conjugate matrices of quaternions generalized inverses Lwner partial order MONOTONICITY
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FEM simulation and experimental verification of temperature field and phase transformation in deep cryogenic treatment 被引量:4
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作者 黎军顽 汤磊磊 +1 位作者 李绍宏 吴晓春 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第10期2421-2430,共10页
Combining with the low temperature material properties and the boiling heat transfer coefficient of specimen immersed in the liquid nitrogen, a numerical model based on metallo-thermo-mechanical couple theory was esta... Combining with the low temperature material properties and the boiling heat transfer coefficient of specimen immersed in the liquid nitrogen, a numerical model based on metallo-thermo-mechanical couple theory was established to reproduce the deep cryogenic treatment (DCT) process of a newly developed cold work die steel Cr8Mo2SiV (SDC99). Moreover, an experimental setup for rapid temperature measurement was designed to validate the simulation results. The investigation suggests that the differences in temperature and cooling rate between the surface and core of specimen are very significant. However, it should be emphasized that the acute temperature and cooling rate changes during DCT are mainly concentrated on the specimen surface region about 1/3 of the sample thickness. Subjected to DCT, the retained austenite of quenched specimen continues to transform to martensite and finally its phase volume fraction reduces to 2.3%. The predicted results are coincident well with the experimental data, which demonstrates that the numerical model employed in this study can accurately capture the variation characteristics of temperature and microstructure fields during DCT and provide a theoretical guidance for making the reasonable DCT procedure. 展开更多
关键词 deep cryogenic treatment boiling heat transfer coefficient finite element method phase transformation cold work tool steel
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Numerical simulation of LWD resistivity response of carbonate formation using self-adaptive hp-FEM 被引量:4
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作者 刘得军 马中华 +2 位作者 邢晓楠 李辉 郭智勇 《Applied Geophysics》 SCIE CSCD 2013年第1期97-108,119,120,共14页
Most of the carbonate formation are highly heterogeneous with cavities of different sizes, which makes the prediction of cavity-filled reservoir in carbonate rocks difficult. Large cavities in carbonate formations pos... Most of the carbonate formation are highly heterogeneous with cavities of different sizes, which makes the prediction of cavity-filled reservoir in carbonate rocks difficult. Large cavities in carbonate formations pose serious threat to drilling operations. Logging-whiledrilling (LWD) is currently used to accurately identify and evaluate cavities in reservoirs during drilling. In this study, we use the self-adaptive hp-FEM algorithm simulate and calculate the LWD resistivity responses of fracture-cavity reservoir cavities. Compared with the traditional h-FEM method, the self-adaptive hp-FEM algorithm has the characteristics of the self-adaptive mesh refinement and the calculations exponentially converge to highly accurate solutions. Using numerical simulations, we investigated the effect of the cavity size, distance between cavity and borehole, and transmitted frequency on the LWD resistivity response. Based on the results, a method for recognizing cavities is proposed. This research can provide the theoretical basis for the accurate identification and quantitative evaluation of various carbonate reservoirs with cavities encountered in practice. 展开更多
关键词 LWD resistivity HP-FEM SELF-ADAPTIVE exponential convergence numerical simulation cavity RESERVOIRS
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0.18μm CMOS programmable frequency divider design for DVB-T
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作者 胡庆生 仲建锋 何小虎 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期159-162,共4页
The implementation of a programmable frequency divider, which is one of the components of the phase-locked loop (PLL) frequency synthesizer for digital video broadcastingterrestrial (DVB-T) and other modem communi... The implementation of a programmable frequency divider, which is one of the components of the phase-locked loop (PLL) frequency synthesizer for digital video broadcastingterrestrial (DVB-T) and other modem communication systems, is presented. By cooperating with a dual-modulus prescaler, this divider can realize an integer frequency division from 926 to 1 387. Besides the traditional standard cell design flow, such as logic synthesis, placement and routing, the interactions between front-end and back-end are also considered to optimize the design flow under deep submicron technology. By back-annotating the back-end information to front-end design, a custom wire-load model is created which is more practical compared with the default model. This divider has been fabricated in TSMC 0. 18μm CMOS technology using Artisan standard cell library. The chip area is 675 μm × 475 μm and the power consumption is about 2 mW under a 1.8 V power supply. Measurement results show that it works correctly and can realize a frequency division with high precision. 展开更多
关键词 programmable frequency divider frequency synthesizer standard cell DVB-T
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