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Research of NO_(2) vertical profiles with look-up table method based on MAX-DOAS
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作者 Yingying Guo Suwen Li +2 位作者 Fusheng Mou Hexiang Qi Qijin Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期332-338,共7页
Obtaining the vertical distribution profile of trace gas is of great significance for studying the diffusion procedure of air pollution.In this article,a look-up table method based on multi-axis differential optical a... Obtaining the vertical distribution profile of trace gas is of great significance for studying the diffusion procedure of air pollution.In this article,a look-up table method based on multi-axis differential optical absorption spectroscopy(MAX-DOAS)technology is established for retrieving the tropospheric NO_(2) vertical distribution profiles.This method retrieves the aerosol extinction profiles with minimum cost function.Then,the aerosol extinction profiles and the atmospheric radiation transfer model(RTM)are employed to establish the look-up table for retrieving the NO_(2) vertical column densities(VCDs)and profiles.The measured NO_(2) differential slant column densities(DSCDs)are compared with the NO_(2) DSCDs simulated by the atmospheric RTM,and the NO_(2) VCDs,the weight factor of NO_(2) in the boundary layer,and the boundary layer height are obtained by the minimization process.The look-up table is established to retrieve NO_(2) VCDs based on MAX-DOAS measurements in Huaibei area,and the results are compared with the data from Copernicus Atmospheric Monitoring Service(CAMS)model.It is found that there are nearly consistent and the correlation coefficient R2 is more than 0.86.The results show that this technology provides a more convenient and accurate retrieval method for the stereoscopic monitoring of atmospheric environment. 展开更多
关键词 multi-axis differential optical absorption spectroscopy look-up table method the cost function NO_(2)vertical profile
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Study on the methods to calculate the numbers of elements in every period in the periodic table
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作者 WU Zhi-fu DENG De-hua +2 位作者 SHEN Yu-hua XIE An-jian CHEN Zhang-xu 《Journal of Chemistry and Chemical Engineering》 2008年第4期71-74,共4页
The previous methods of figuring the numbers of chemical elements is summed up in this paper. Based on that, another two creative calculative methods are introduced as well.
关键词 the periodic table of elements the odd number theeven number calculative methods
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Mapping of the Water Table Levels of Unconfined Aquifers Using Two Interpolation Methods
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作者 Oswaldo Augusto Filho Wanessa Soares Clemente Iriguay Fernandéz 《Journal of Geographic Information System》 2016年第4期480-494,共16页
The spatial prediction of the water table can be used for many applications related to civil works (foundations, excavations) and other urban and environmental management activities. Deterministic and geostatistical i... The spatial prediction of the water table can be used for many applications related to civil works (foundations, excavations) and other urban and environmental management activities. Deterministic and geostatistical interpolation methods were used to predict the spatial distribution of water table levels (unconfined aquifers) of important geological formations of the Joao Pessoa City (capital of Paraiba State, Brazil) with dense urban occupation and high demand for new civil works. The deterministic (topo to raster) and geostatistical (ordinary kriging) interpolation methods were evaluated using a Geographic Information System (GIS)-based investigation. The water table levels were obtained from 276 boring logs of Standard Penetration Test (SPT) in situ investigation distributed over the geological formations studied (an area of 59.8 km<sup>2</sup>, covering 40 districts of the Joao Pessoa City). The Nspt values and textural characterization data are stored for levels of 1 m depth. Some boreholes located in the area investigated were not included in the interpolation processes in order to be compared with estimated values (validation of the results). Maps of the water table depths were also produced to further analyze the quality of the water table surfaces interpolated by both methods. The phreatic surface interpolations provided satisfactory results for both methods (RMSE = 1.8 m). The topo to raster method showed a slight general tendency to be less affected by local values in relation to the kriging method and also has the advantage of integrating the drainage flow system, which is a relevant aspect for spatial models of the water table levels of unconfined aquifers. The ordinary kriging (geostatistical method) provides a prediction surface and some measure of the certainty or accuracy of the predictions. 展开更多
关键词 Water table Deterministic and Geostatistical Interpolation methods SPT Boreholes Geological-Geotechnical Database
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Seismic response of underground utility tunnels: shaking table testing and FEM analysis 被引量:38
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作者 Jiang Luzhen Chen Jun Li Jie 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2010年第4期555-567,共13页
Underground utility tunnels are widely used in urban areas throughout the world for lifeline networks due to their easy maintenance and environmental protection capabilities. However, knowledge about their seismic per... Underground utility tunnels are widely used in urban areas throughout the world for lifeline networks due to their easy maintenance and environmental protection capabilities. However, knowledge about their seismic performance is still quite limited and seismic design procedures are not included in current design codes. This paper describes a series of shaking table tests the authors performed on a scaled utility tunnel model to explore its performance under earthquake excitation. Details of the experimental setup are first presented focusing on aspects such as the design of the soil container, scaled structural model, sensor array arrangement and test procedure. The main observations from the test program, including structural response, soil response, soil-structure interaction and earth pressure, are summarized and discussed. Further, a finite element model (FEM) of the test utility tunnel is established where the nonlinear soil properties are modeled by the Drucker- Prager constitutive model; the master-slave surface mechanism is employed to simulate the soil-structure dynamic interaction; and the confining effect of the laminar shear box to soil is considered by proper boundary modeling. The results from the numerical model are compared with experiment measurements in terms of displacement, acceleration and amplification factor of the structural model and the soil. The comparison shows that the numerical results match the experimental measurements quite well. The validated numerical model can be adopted for further analysis. 展开更多
关键词 lifeline system utility tunnel shaking table test finite element method soil-structure interaction
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A general purpose exact Rayleigh scattering look-up table for ocean color remote sensing 被引量:5
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作者 HE Xianqiang PAN Delu +1 位作者 BAI Yan GONG Fang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第1期48-56,共9页
The current exact Rayleigh scattering calculation of ocean color remote sensing uses the look-up table (LUT), which is usually created for a special remote sensor and cannot be applied to other sensors. For practica... The current exact Rayleigh scattering calculation of ocean color remote sensing uses the look-up table (LUT), which is usually created for a special remote sensor and cannot be applied to other sensors. For practical application, a general purpose Rayleigh scattering LUT which can be applied to all ocean color remote sensors is generated. An adding-doubling method to solve the vector radiative transfer equation in the plane-parallel atmosphere is deduced in detail. Compared with the exact Rayleigh scattering radiance derived from the MODIS exact Rayleigh scattering LUT, it is proved that the relative error of Rayleigh scattering calculation with the adding-doubling method is less than 0.25%, which meets the required accuracy of the atmospheric correction of ocean color remote sensing. Therefore, the adding-doubling method can be used to generate the exact Rayleigh scattering LUT for the ocean color remote sensors. Finally, the general purpose exact Rayleigh scattering LUT is generated using the adding-doubling method. On the basis of the general purpose LUT, the calculated Rayleigh scattering radiance is tested by comparing with the LUTs ofMODIS, SeaWiFS and the other ocean color sensors, showing that the relative errors are all less than 0.5%, and this general purpose LUT can be applied to all ocean color remote sensors. 展开更多
关键词 ocean color Rayleigh scattering look-up table radiative transfer adding-doubling method
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Numerical simulations of shake-table experiment for dynamic soil-pile-structure interaction in liquefi able soils 被引量:15
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作者 Tang Liang Baydaa Hussain Maula +1 位作者 Ling Xianzhang Su Lei 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第1期171-180,共10页
A shake-table experiment on pile foundations in liquefi able soils composed of liquefi able sand and overlying soft clay is studied. A three-dimensional(3D) effective stress fi nite element(FE) analysis is employed to... A shake-table experiment on pile foundations in liquefi able soils composed of liquefi able sand and overlying soft clay is studied. A three-dimensional(3D) effective stress fi nite element(FE) analysis is employed to simulate the experiment. A recently developed multi-surface elasto-plastic constitutive model and a fully coupled dynamic inelastic FE formulation(u-p) are used to model the liquefaction behavior of the sand. The soil domains are discretized using a solid-fl uid fully coupled(u-p) 20-8 noded brick element. The pile is simulated using beam-column elements. Upon careful calibration, very good agreement is obtained between the computed and the measured dynamic behavior of the ground and the pile. A parametric analysis is also conducted on the model to investigate the effect of pile-pinning, pile diameter, pile stiffness, ground inclination angle, superstructure mass and pile head restraints on the ground improvement. It is found that the pile foundation has a noticeable pinning effect that reduces the lateral soil displacement. It is observed that a larger pile diameter and fi xed pile head restraints contribute to decreasing the lateral pile deformation; however, a higher ground inclination angle tends to increase the lateral pile head displacements and pile stiffness, and superstructure mass seems to effectively infl uence the lateral pile displacements. 展开更多
关键词 LIQUEFACTION pile pinning soil improvement pile deformation EARTHQUAKE nonlinear fi nite element method shake-table experiment
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Stable Routh-Padé-type approximation in model reduction of interval systems
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作者 顾传青 杨健 《Journal of Shanghai University(English Edition)》 CAS 2010年第5期369-373,共5页
An interval Pade-type approximation is introduced and then Routh-Pade-type method (IRPTM) is presented to model reduction in interval systems. The denominator in reduced model is obtained from the stable Routh table... An interval Pade-type approximation is introduced and then Routh-Pade-type method (IRPTM) is presented to model reduction in interval systems. The denominator in reduced model is obtained from the stable Routh table, and its numerator is constructed by the interval Pade-type definition. Compared to the existing Routh-Pade method, IRPTM does not need to solve linear interval equations theoretical analysis shows that IRPTM has example is given to illustrate our method. Hence, we do not have to compute smaller computational cost than that interval division in the process. Moreover, of Routh-Pade method. A typical numerical 展开更多
关键词 interval system model reduction Routh-table Pade-type approximant Routh-Pad6-type method
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特高压GIS套管内绝缘失效地震易损性分析
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作者 石高扬 谢强 《工程力学》 北大核心 2026年第1期260-268,共9页
特高压套管外套筒-导电杆体系在地震作用下存在电气功能失效的风险。为了研究导电杆位移引起的套管内绝缘失效,建立外套筒-导电杆耦联体系理论模型,利用±1100 kV复合材料GIS套管振动台试验和有限元分析进行模型验证,研究外套筒-导... 特高压套管外套筒-导电杆体系在地震作用下存在电气功能失效的风险。为了研究导电杆位移引起的套管内绝缘失效,建立外套筒-导电杆耦联体系理论模型,利用±1100 kV复合材料GIS套管振动台试验和有限元分析进行模型验证,研究外套筒-导电杆相互作用机理及地震易损性,结果表明:地震作用下套管内绝缘失效模式主要来源于:外套筒顶部位移引起的导电杆变形、导电杆自身受到的地震激励,其中外套筒顶部位移是引起内绝缘失效的主要原因;外套筒与导电杆的相对位移沿着高度呈现出近似抛物线分布规律,最大值点位于套管重心下部;相同地震强度作用下,特高压套管内绝缘失效概率介于套管根部断裂和顶部牵拉失效概率之间。外套筒-导电杆体系相对位移的地震响应可以通过建立耦联体系理论模型求得,应该同时关注内绝缘失效和套管根部断裂失效对电气功能的影响。 展开更多
关键词 特高压GIS套管 振动台试验 内绝缘失效 外套筒-导电杆体系 分析方法
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Synthesis of Water Utilization System Using Concentration Interval Analysis Method ( Ⅰ ) Non-Mass-Transfer-Based Operation 被引量:3
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作者 刘永健 袁希钢 罗祎青 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第3期361-368,共8页
A strategy for water and wastewater minimization is developed for continuous water utilization systems involving fixed flowrate(non-mass-transfer-based)operations,based on the fictitious operations that is introduced ... A strategy for water and wastewater minimization is developed for continuous water utilization systems involving fixed flowrate(non-mass-transfer-based)operations,based on the fictitious operations that is introduced to represent the water losing and/or generating operations and a modified concentration interval analysis(MCIA) technique.This strategy is a simple,nongraphical,and noniterative procedure and is suitable for the quick yields of targets and the identification of pinch point location.Moreover,on the basis of the target method,a heuristic-based approach is also presented to generate water utilization networks,which could be demonstrated to be optimum ones. The proposed approaches are illustrated with example problems. 展开更多
关键词 water minimization water utilization network targeting method concentration interval table
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Simple Method for Dynamic Responses of Soil-Pile-Isolated Structure Interaction System 被引量:1
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作者 Yu Xu Zhuang Haiyang Liu Shuai 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第4期426-437,共12页
To investigate the effect of soil-pile-structure interaction(SPSI effect)on the dynamic response of a baseisolated structure with buried footings on a pile foundation,certain shake table tests are previously conducted... To investigate the effect of soil-pile-structure interaction(SPSI effect)on the dynamic response of a baseisolated structure with buried footings on a pile foundation,certain shake table tests are previously conducted.Based on the test results and the existing related studies,an efficient simplified model and a corresponding calculation method are verified for estimating the dynamic characteristics of a base-isolated structure with buried footings on a pile foundation with the SSI effect.In this method,the solutions by Veletsos and co-workers for a non-isolated structure with the SSI effect are verified and advanced for a base-isolated structure,and the solutions by Maravas and co-workers for a non-isolated structure on a pile foundation are introduced to consider the effect of the piles.By comparison with the shake table test,this work proves that the simplified method can efficiently estimate the dynamic responses of a base-isolated structure with buried footings on a pile foundation.Using parameter analysis,this work also shows that the dynamic characteristics of a non-isolated structure are quite similar to those of the base-isolated structure when the soil foundation is sufficiently soft,which means that the isolation layer gradually loses its isolation function as the soil foundation softens. 展开更多
关键词 soil-structure interaction(SSI) base-isolated structure seismic response shake table test simplified method
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Determining the Basaltic Sequence Using Seismic Reflection and Resistivity Methods 被引量:1
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作者 A. Alanezi A. Qadrouh 《Open Journal of Geology》 2013年第2期17-21,共5页
This study was carried out in Harat Rahat (south of Almadinah Almonwarah) using seismic reflection and resistivity methods. The main objectives of this study are to determine the extent of the basaltic layer and to de... This study was carried out in Harat Rahat (south of Almadinah Almonwarah) using seismic reflection and resistivity methods. The main objectives of this study are to determine the extent of the basaltic layer and to define the subsurface faults and fractures that could affect and control the groundwater movement in the study area. A 2D seismic profile was acquired and the result shows that the subsurface in the study area has a major fault. We obtained a well match when the seismic result was compared with drilled wells. As a complementary tool, the resistivity method was applied in order to detect the groundwater level. The results of the resistivity method showed that six distinct layers have been identified. The interpretation of these six layers show that the first three layers, the fourth layer, the fifth layer and the bottom of the section indicated various subsurface structures and lithologies;various basaltic layers, fractured basalt, weathered basement and fresh basaltic layers, respectively. It is obvious that the eventual success of geophysical surveys depend on the combination with other subsurface data sources in order to produce accurate maps. 展开更多
关键词 SEISMIC method Vertical Electrical SOUNDING (VES) Water table
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A Discrete Newton's Method for Gain Based Predistorter 被引量:1
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作者 Xiaochen LIN Minglu JIN Aifei LIU 《International Journal of Communications, Network and System Sciences》 2008年第1期16-21,共6页
Gain based predistorter (PD) is a highly effective and simple digital baseband predistorter which compensates for the nonlinear distortion of PAs. Lookup table (LUT) is the core of the gain based PD. This paper presen... Gain based predistorter (PD) is a highly effective and simple digital baseband predistorter which compensates for the nonlinear distortion of PAs. Lookup table (LUT) is the core of the gain based PD. This paper presents a discrete Newton’s method based adaptive technique to modify LUT. We simplify and convert the hardship of adaptive updating LUT to the roots finding problem for a system of two element real equations on athematics. And we deduce discrete Newton’s method based adaptive iterative formula used for updating LUT. The iterative formula of the proposed method is in real number field, but secant method previously published is in complex number field. So the proposed method reduces the number of real multiplications and is implemented with ease by hardware. Furthermore, computer simulation results verify gain based PD using discrete Newton’s method could rectify nonlinear distortion and improve system performance. Also, the simulation results reveal the proposed method reaches to the stable statement in fewer iteration times and less runtime than secant method. 展开更多
关键词 PREDISTORTION DISCRETE Newton’s method Power Amplifiers (PAs) LOOKUP table (LUT)
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Risk Assessment Framework and Algorithm of Power Systems Based on the Partitioned Multi-objective Risk Method 被引量:11
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作者 XIE Shaoyu WANG Xiuli WANG Xifan 《中国电机工程学报》 EI CSCD 北大核心 2011年第34期I0005-I0005,7,共1页
针对平均风险指标无法区分高损失-低概率事件及低损失-高概率事件的缺点,提出了电力系统的分割多目标风险分析框架。该框架将电力系统的风险状态细分为低损失、中等损失和高损失3个风险范围,并提出3个损失范围条件风险函数和条件风险概... 针对平均风险指标无法区分高损失-低概率事件及低损失-高概率事件的缺点,提出了电力系统的分割多目标风险分析框架。该框架将电力系统的风险状态细分为低损失、中等损失和高损失3个风险范围,并提出3个损失范围条件风险函数和条件风险概率的概念。采用经典的容量停运表模型,建立了这些条件期望指标的计算方法。对IEEE-RTS及TH-RTS2000系统进行了分割多目标风险评估,研究不同负荷水平下系统风险在3个损失范围的分布及转移情况,并分析损失分割点对系统风险的影响。通过分割多目标风险分析,风险分析者和决策者可以权衡系统的平均风险以及高、中、低损失范围的条件期望风险,从而对系统的风险状况有一个全面和深入的了解。 展开更多
关键词 英文摘要 内容介绍 编辑工作 期刊
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Synthesis of Water Utilization System Using Concentration Interval Analysis Method (Ⅱ) Discontinuous Process
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作者 刘永健 袁希钢 罗祎青 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第3期369-375,共7页
The first part of the series of this article proposed a systematic method for the synthesis of continuous water-using system involving both non-mass-transfer-based and mass-transfer-based operations.This article,by ex... The first part of the series of this article proposed a systematic method for the synthesis of continuous water-using system involving both non-mass-transfer-based and mass-transfer-based operations.This article,by ex- tending the method,proposes a time-dependent concentration interval analysis(CIA)method to solve the problems associated with the synthesis of discontinuous or batch water-using systems involving both non-mass-transfer-based and mass-transfer-based operation.This method can effectively identify the possibility of water reuse and the amount of water reused under time constraints for minimizing the consumption of freshwater in single or repeated batch/discontinuous water-using systems.Moreover,on the basis of the heuristic method adapted from concentra- tion interval analysis method for the continuous process network design,the network design for the discontinuous or batch process can be obtained through the designs for every time interval.Case study illustrates that the method presented in this article can simultaneously minimize the freshwater consumption in single or repeated batch/discontinuous water system and can determine a preferable storage tank capacity for some problems. 展开更多
关键词 water network target method discontinuous process concentration-interval table
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Seismic effectiveness evaluation and optimized design of tie up method for securing museum collections
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作者 Wang Meng Yan Yi +3 位作者 Yang Weiguo Liu Pei Ge Jiaqi Ma Botao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期741-763,共23页
To quantify the seismic effectiveness of the most commonly used fishing line tie up method for securing museum collections and optimize fixed strategies for exhibitions,shaking table tests of the seismic systems used ... To quantify the seismic effectiveness of the most commonly used fishing line tie up method for securing museum collections and optimize fixed strategies for exhibitions,shaking table tests of the seismic systems used for typical museum collection replicas have been carried out.The influence of body shape and fixed measure parameters on the seismic responses of replicas and the interaction behavior between replicas and fixed measures have been explored.Based on the results,seismic effectiveness evaluation indexes of the tie up method are proposed.Reasonable suggestions for fixed strategies are given,which provide a basis for the exhibition of delicate museum collections considering the principle of minimizing seismic responses and intervention.The analysis results show that a larger ratio of height of mass center to bottom diameter led to more intense rocking responses.Increasing the initial pretension of fishing lines was conducive to reducing the seismic responses and stress variation of the lines.Through comprehensive consideration of the interaction forces and effective securement,it is recommended to apply 20%of breaking stress as the initial pretension.For specific museum collections that cannot be effectively protected by the independent tie up method,an optimized strategy of a combination of fishing lines and fasteners is recommended. 展开更多
关键词 tie up method museum collections shaking table test seismic effectiveness optimized design
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Mathematical Programming Method as a Means of Calibration of NIR Analyzers
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作者 Ilya Skutin Konstantin Zharinov Maria Sushkova 《Journal of Chemistry and Chemical Engineering》 2012年第8期692-697,共6页
In addition to the conventional methods of the calibration model construction, such as PCR (principal components regression) and PLS (partial least-squares), a MPM (mathematical programming method) is developed ... In addition to the conventional methods of the calibration model construction, such as PCR (principal components regression) and PLS (partial least-squares), a MPM (mathematical programming method) is developed and proposed for practical use in NIR analyses of agricultural and food products. The proposed method involves the mathematical programming techniques to seek the regression coefficients for the calibration model calculation. It is based on the optimization theory used for finding the extremum of the objective function in the given domain of a vector space and employs the method of the complementarity problems solving. The MPM algorithm is described in detail. The MPM was tested on an InfraLUM FT-10 NIR analyzer of Lumex company with samples of dry milk (for fat), corn (for protein) and rye flour (for moisture). The obtained results show that the MPM can be used for constructing multivariate calibrations with the qualitative characteristics superior over those of the classical PCR and PLS methods of analysis. 展开更多
关键词 CHEMOMETRICS multivariate calibration mathematical programming simplex table method.
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A Novel Hybrid Encryption Method Based on Honey Encryption and Advanced DNA Encoding Scheme in Key Generation
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作者 Nwe Ni Khin Thanda Win 《Journal of Computer and Communications》 2022年第9期22-36,共15页
Nowadays, increased information capacity and transmission processes make information security a difficult problem. As a result, most researchers employ encryption and decryption algorithms to enhance information secur... Nowadays, increased information capacity and transmission processes make information security a difficult problem. As a result, most researchers employ encryption and decryption algorithms to enhance information security domains. As it progresses, new encryption methods are being used for information security. In this paper, a hybrid encryption algorithm that combines the honey encryption algorithm and an advanced DNA encoding scheme in key generation is presented. Deoxyribonucleic Acid (DNA) achieves maximal protection and powerful security with high capacity and low modification rate, it is currently being investigated as a potential carrier for information security. Honey Encryption (HE) is an important encryption method for security systems and can strongly prevent brute force attacks. However, the traditional honeyword encryption has a message space limitation problem in the message distribution process. Therefore, we use an improved honey encryption algorithm in our proposed system. By combining the benefits of the DNA-based encoding algorithm with the improved Honey encryption algorithm, a new hybrid method is created in the proposed system. In this paper, five different lookup tables are created in the DNA encoding scheme in key generation. The improved Honey encryption algorithm based on the DNA encoding scheme in key generation is discussed in detail. The passwords are generated as the keys by using the DNA methods based on five different lookup tables, and the disease names are the input messages that are encoded by using the honey encryption process. This hybrid method can reduce the storage overhead problem in the DNA method by applying the five different lookup tables and can reduce time complexity in the existing honey encryption process. 展开更多
关键词 Honey Encryption DNA Encoding Hybrid method Data Lookup tables Time Complexity Storage Overhead
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A Study of Different Unwarping Methods for Omnidirectional Imaging
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作者 Wee Shen Pua Wai Kit Wong +1 位作者 Chu Kiong Loo Way Soong Lim 《Computer Technology and Application》 2012年第3期226-239,共14页
Omni-directional imaging system is becoming more and more common in reducing the maintenance fees and the number of cameras used as well as increasing the angle of view in a single camera. Due to omni-directional imag... Omni-directional imaging system is becoming more and more common in reducing the maintenance fees and the number of cameras used as well as increasing the angle of view in a single camera. Due to omni-directional images are not directly understandable, an approach namely the un-warping process, has been implemented in converting the omni-directional image to a panoramic image, making it understandable. There are different kinds of methods used for the implementation of this approach. This paper evaluates the performance of the 3 universal un-warping methods currently applied actively around the world in transforming omni-directional image to panoramic image, namely the pano-mapping table method, discrete geometry method (DGT) and the log-polar mapping method. The algorithm of these methods will first be proposed, and the code will then be generated and be tested on several different omni-directional images. The images converted will then be compared among each other and be evaluated based on their performance on the resolutions, quality, algorithm used, complexity based on Big-O computations, processing time, and finally their data compression rate available for each of the methods. The most preferable un-warping method will then be concluded, taking into considerations all these factors. 展开更多
关键词 Omnidirectional image evaluation of image quality un-warping discrete geometry techniques DGT (discrete geometrymethod pano-mapping table method log-polar mapping.
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考虑电力调配的省级民用建筑碳排放核算方法研究——以河北省为例 被引量:2
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作者 朱丽 李明杰 +1 位作者 严哲星 安莹 《建筑节能(中英文)》 2025年第2期7-12,共6页
在实现“双碳”目标的背景下,省级建筑领域碳排放核算研究的重要性逐渐提升。目前,采用区域电网排放因子计算得到的省级建筑碳排放,未考虑各省的电力调入调出和资源禀赋状况,碳排放计算结果有一定偏差,无法真实体现省级区域逐年碳排放... 在实现“双碳”目标的背景下,省级建筑领域碳排放核算研究的重要性逐渐提升。目前,采用区域电网排放因子计算得到的省级建筑碳排放,未考虑各省的电力调入调出和资源禀赋状况,碳排放计算结果有一定偏差,无法真实体现省级区域逐年碳排放变化情况。考虑省际电力调配,提出逐年动态电力碳排放因子计算方法,以河北省为研究区域,采用能源平衡表拆分法计算得到河北省2010年-2020年民用建筑碳排放总量情况,分析了变化趋势,旨在为省级建筑碳排放核算研究提供参考依据,同时为河北省建筑领域碳减排研究提供基础。结果表明:2010年-2020年,河北省民用建筑碳排放总量整体呈现持续增长的趋势,11年间增长至原来的1.7倍。年度增长率总体上呈正增长趋势,2013年-2018年为高增长阶段。与区域电网排放因子相比,省级逐年动态电力排放因子核算结果更有利于表达省级区域逐年碳排放的真实情况。 展开更多
关键词 河北省 民用建筑碳排放 逐年动态碳排放因子 能源平衡表拆分法
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基于飞机全动垂尾结构的抖振载荷加载方法研究
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作者 李益萱 张飞 +3 位作者 李凯翔 白春玉 刘小川 王彬文 《西北工业大学学报》 北大核心 2025年第5期888-895,共8页
在大攻角飞行等严酷工况下高机动性飞机的一些典型结构,如全动垂尾结构,会发生强烈的抖振,亟需开展抖振载荷和气动载荷联合作用下的动态疲劳试验。针对此类试验中抖振载荷的加载需求,设计研发了“双液压球头+橡胶板”抖振加载系统与振... 在大攻角飞行等严酷工况下高机动性飞机的一些典型结构,如全动垂尾结构,会发生强烈的抖振,亟需开展抖振载荷和气动载荷联合作用下的动态疲劳试验。针对此类试验中抖振载荷的加载需求,设计研发了“双液压球头+橡胶板”抖振加载系统与振动台随动加载系统。该系统通过实时追踪垂尾变形后的空间姿态,实现了对变形翼面的垂直加载,同时采用低干扰力控技术将加载装置对结构动力学特性的影响降至最小。基于具有相同动特性的垂尾模拟件,开展了加载方法的试验验证。结果表明:文中提出的加载方法可稳定施加低、中、高量级抖振载荷,系统运行可靠且数据完整有效,验证了其满足全动垂尾动态疲劳试验的技术要求,具有直接工程应用价值,可推广至真实结构的试验中。 展开更多
关键词 全动垂尾结构 动态疲劳试验 振动台随动系统 抖振载荷加载 试验验证
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