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基于分程Clapper-Yule模型的消光膜凹版印刷光谱预测模型的研究

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印刷与数字媒体技术研究 2024年第1期 24-30页

作者：武城运郭凌华张宜洋陕西科技大学轻工科学与工程学院西安710021 陕西科技大学中国轻工业功能印刷与运输包装重点实验室西安710021

为了建立可以精确预测消光膜上凹版印刷的颜色光谱预测模型,本研究提出一种基于分程Clapper-Yule模型的光谱预测方法。以包含729个色块的IT8.7-4色靶为实验样本,利用Matlab软件建立分程系数数据集,以CIE DE1976色差公式为消光膜凹版印... 详细信息

为了建立可以精确预测消光膜上凹版印刷的颜色光谱预测模型,本研究提出一种基于分程Clapper-Yule模型的光谱预测方法。以包含729个色块的IT8.7-4色靶为实验样本,利用Matlab软件建立分程系数数据集,以CIE DE1976色差公式为消光膜凹版印刷光谱预测模型的评价指标,并与现有的光谱预测模型进行了对比。实验结果表明,消光膜凹版印刷光谱预测模型色差ΔE~*_(ab)在0~3之间,占比为75%,整体平均色差ΔE~*_(ab)为1.7。本研究所建立的模型相较于经典Clapper-Yule模型具有较高的预测精度,能满足凹版印刷消光膜对颜色复制的需求。

关键词： Clapper-Yule模型分程系数光谱反射率消光膜

Humic-Like Substances from Different Compost Extracts Could Significantly Promote Cucumber Growth

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Pedosphere 2012年第6期22卷 815-824页

作者： XU Da-Bing WANG Qiu-Jun wu yun-cheng YU Guang-Hui SHEN Qi-Rong HUANG Qi-Wei Jiangsu Provincial Key Lab for Organic Solid Waste Utilization Nanjing Agricultural UniversityNanjing 210095(China)

The effects of direct extracts of compost (DEC), aerated fermentation extracts of compost (AFEC) and non-aerated fermentation extracts of compost (NAFEC) on cucumber growth and the action mechanisms were evaluated based on the structure and activity analysis of humic-like substances. AFEC increased cucumber growth most significantly, followed by DEC and NAFEC, which was insignificant compared to the control treatment. Humic-like substances from compost extracts played an important role in promoting cucumber growth. Application of humic-like substances stimulated auxin-like activity and increased chlorophyll content and nitrogen accumulation in plants. The positive auxin-like activity of humic-like substances could be attributed to the relative distribution of special carbon groups, such as those with a large amount of peptidic and carbohydratic groups or with a low content of phenolic groups. In conclusion, the best growth promotion by application of AFEC was mainly attributed to the humic-like substances in the AFEC.

关键词： auxin-like activity 13C nuclear magnetic resonance chemical structure elemental composition analysis

Infiltration,runoff,and slope stability behaviors of infinite slope with macropores based on an improved Green–Ampt model

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Journal of Mountain Science 2024年第7期21卷 2220-2235页

作者： LI Shanghui wu Guoxiong QUE yun JIANG Zhenliang cheng Gaoyun College of Intelligent Construction Fuzhou University of International Studies and TradeFuzhou 350202China College of Civil Engineering Chongqing Jiao Tong UniversityChongqing 400074China Chongqing Vocational College of Architectural Engineering Chongqing 400072China College of Civil Engineering Fuzhou UniversityFuzhou 350000China Department of Civil and Environmental Engineering Hong Kong University of Science and TechnologyHong Kong 999077China T.Y.Lin International Engineering Consulting(China)Co.Ltd Chongqing 401120China

Infiltration–runoff–slope instability mechanism of macropore slope under heavy rainfall is *** paper studied its instability mechanism with an improved Green–Ampt(GA)model considering the dual-porosity(i.e.,matrix and macropore)and ponding condition,and proposed the infiltration equations,infiltration–runoff coupled model,and safety factor calculation *** show that the infiltration processes of macropore slope can be divided into three stages,and the proposed model is rational by a comparative *** wetting front depth of the traditional unsaturated slope is 17.2%larger than that of the macropore slope in the early rainfall stage and 27%smaller than that of the macropore slope in the late rainfall ***,macropores benefit the slope stability in the early rainfall but not in the *** flow does not occur initially but becomes pronounced with increasing rainfall *** equal depth of the wetting front in the two domains is regarded as the onset criteria of macropore *** analysis shows that macropore flow is delayed by increasing proportion of macropore domain(ω_(f)),whereas promoted by increasing ratio of saturated permeability coefficients between the two domains(μ).The increasing trend of ponding depth is sharp at first and then grows ***,when rainfall duration is less than 3 h,ωf andμhave no significant effect on the safety factor,whereas it decreases with increasingωf and increases with increasingμunder longer duration(≥3 h).With the increase ofω_(f),the slope maximum instability time advances by 10.5 h,and with the increase ofμ,the slope maximum instability time delays by 3.1 h.

关键词： Macropore slope Green–Ampt infiltration model Equivalent wetting front Ponding response time Slope stability

Anti-Spoofing:Integrated Information Authentication of BeiDou-ⅡCivil Navigation Message

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China Communications 2024年第9期21卷 242-261页

作者： wu Zhijun Liang cheng Zhang yun Liu Rusen Yue Meng School of Safety Science and Engineering Civil Aviation University of ChinaTianjin 300300China School of Electronic Information and Automation Civil Aviation University of ChinaTianjin 300300China Dalian Air Traffic Management Station of Civil Aviation of China Dalian 116000China

The BeiDou-Ⅱcivil navigation message(BDⅡ-CNAV)is transmitted in an open environment and no information integrity protection measures are ***,the BDⅡ-CNAV faces the threat of spoofing attacks,which can lead to wrong location reports and time *** order to deal with this threat,we proposed a scheme of anti-spoofing for BDⅡ-CNAV based on integrated information *** scheme generates two type authentication information,one is authentication code information(ACI),which is applied to confirm the authenticity and reliability of satellite time information,and the other is signature information,which is used to authenticate the integrity of satellite location information and other *** authentication information is designed to embed into the reserved bits in BDⅡ-CNAV without changing the frame *** order to avoid authentication failure caused by public key error or key error,the key or public key prompt information(KPKPI)are designed to remind the receiver to update both keys in *** results indicate that the scheme can successfully detect spoofing attacks,and the authentication delay is less than 1%of the transmission delay,which meets the requirements of BDⅡ-CNAV information authentication.

关键词： anti-spoofing authentication BeiDou-II civil navigation message(BDII-CNAV) signature spoofing attack

Effect of the vortical structures on the hydrodynamic performance of a pitching hydrofoil

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Journal of Hydrodynamics 2024年第2期36卷 406-420页

作者： Rui Yuan Hui-yun Hao Qin wu yun-qing Liu Biao Huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China

The objective is to study the vortical structural behaviors of a transient pitching hydrofoil and their effects on the hydrodynamic performance. The pitching motion of the hydrofoil is set to pitch up with an almost constant rate from 5° to 15° and then back to 5°, with the Reynolds number 4.4×10^(5) and the frequency 2 Hz. The results show that the main coherent structures around the pitching hydrofoil include small-scale laminar separation bubble (LSB), large-scale second vortex (SV) and trailing edge vortex (TEV) which are all vortical. The relationship between the vortical structure and the lift is investigated with the finite-domain impulse theory. It indicates that the major part of the lift is contributed by the LSB, whereas the shedding and the formation of the SV and TEV cause the fluctuation of the lift. The proper orthogonal decomposition (POD) method is applied to capture the most energetic modes, revealing that the LSB mode occupies a large amount of energy in the flow field. The dynamic mode decomposition (DMD) method accurately extracts the dominant frequency and modal characteristics, with the first mode corresponding to the mean flow, the second mode corresponding to the LSB structure and the third and fourth modes corresponding to the vortex shedding.

关键词： Hydrodynamics vortical structures finite-domain impulse theory proper orthogonal decomposition(POD) dynamic mode decomposition(DMD) Pitching hydrofoil

Integrated Chinese and Western Medicine in Treatment of Bronchopleural Fistula with Mycobacterium abscessus:A Case Report

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Chinese Journal of Integrative Medicine 2024年第8期30卷 742-746页

作者： WANG Qian-yun cheng Miao BAN cheng-jun ZHANG Li-shan WANG Hong-wu YANG Bing ZOU Heng WANG Ming-zhe The First Clinical Medical College of Beijing University of Chinese Medicine Beijing100700China Department of Respiratory Dongzhimen HospitalBeijing University of Chinese MedicineBeijing100700China

Bronchopleural fistula(BPF)is defined as a pathological connection between the trachea or bronchus and the pleural *** may occur as a serious complication after lung surgery.^((1))It has a low incidence of 1%-3%^((2.3... 详细信息

关键词： pleural lung surgery

A Novel CCA-NMF Whitening Method for Practical Machine Learning Based Underwater Direction of Arrival Estimation

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Journal of Beijing Institute of Technology 2024年第2期33卷 163-174页

作者： yun wu Xinting Li Zhimin Cao School of Physics and Electronic Engineering Northeast Petroleum UniversityDaqing 163318China

Underwater direction of arrival(DOA)estimation has always been a very challenging theoretical and practical *** to the serious non-stationary,non-linear,and non-Gaussian characteristics,machine learning based DOA estimation methods trained on simulated Gaussian noised array data cannot be directly applied to actual underwater DOA estimation *** order to deal with this problem,environmental data with no target echoes can be employed to analyze the non-Gaussian ***,the obtained information about non-Gaussian components can be used to whiten the array *** on these considerations,a novel practical sonar array whitening method was ***,based on a weak assumption that the non-Gaussian components in adjacent patches with and without target echoes are almost the same,canonical cor-relation analysis(CCA)and non-negative matrix factorization(NMF)techniques are employed for whitening the array *** the whitened array data,machine learning based DOA estimation models trained on simulated Gaussian noised datasets can be used to perform underwater DOA estimation *** results illustrated that,using actual underwater datasets for testing with known machine learning based DOA estimation models,accurate and robust DOA estimation performance can be achieved by using the proposed whitening method in different underwater con-ditions.

关键词： direction of arrival(DOA) sonar array data underwater disturbance machine learn-ing canonical correlation analysis(CCA) non-negative matrix factorization(NMF)

Capillary Property of Entangled Porous Metallic Wire materials and Its Application in Fluid Buffers:Theoretical Analysis and Experimental Study

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Defence Technology（防务技术） 2024年第1期31卷 400-416页

作者： Yu Tang Yiwan wu Hu cheng Rong Liu Engineering Research Center for Metal Rubber School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou 350156China AECC Guizhou Liyang Aviation Power Co. LTDGuiyang 550014China College of Computer and Information Sciences Fujian Agriculture and Forestry UniversityFuzhou 350156China

Strong impact does serious harm to the military industries so it is necessary to choose reasonable cushioning material and design effective buffers to prevent the impact of *** on the capillary property entangled porous metallic wire materials(EPMWM),this paper designed a composite buffer which uses EPMWM and viscous fluid as cushioning materials under the low-speed impact of the recoil force device of weapon equipment(such as artillery,mortar,etc.).Combined with the capillary model,porosity,hydraulic diameter,maximum pore diameter and pore distribution were used to characterize the pore structure characteristics of *** calculation model of the damping force of the composite buffer was *** low-speed impact test of the composite buffer was *** parameters of the buffer under low-speed impact were identified according to the model,and the nonlinear model of damping force was *** test results show that the composite buffer with EPMWM and viscous fluid can absorb the impact energy from the recoil movement effectively,and provide a new method for the buffer design of weapon equipment(such as artillery,mortar,etc.).

关键词： Entangled porous metallic wire materials Capillary property Viscousfluid Low-speed impact Damping force

Selection Method for New Energy Output Guaranteed Rates Considering Optimal Energy Storage Configuration

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 539-547页

作者： Xin cheng Tong wu Wei Yao Yan Yang Guangdong Power Grid Corporation Guangzhou 510620China State Key Laboratory of Advanced Electromagnetic Engineering and Technology and School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The output of new energy represented by wind power and photovoltaic power features volatility and randomness. It is a practical approach to use the guaranteed rate with statistical characteristics to analyze the output coefficient of new energy. However, there is a lack of analysis and demonstration on the value of the new energy output guaranteed rate. To solve this problem, a selection method for the new energy output guaranteed rate considering optimal energy storage configuration is proposed. First, the influence of the new energy output guaranteed rate on the new energy output coefficient is analyzed. Secondly, with the goal of minimizing the comprehensive costs, an optimal configuration model of energy storage based on the output guaranteed rate of new energy is constructed, and particle swarm optimization is used for the optimization solution. Then, according to the optimal energy storage configuration results under different guaranteed rates, a reasonable new energy output guaranteed rate is determined by maximizing the comprehensive benefits obtained from energy storage. Finally, an example applied to the power grid in an area of Guangdong in Southern China is provided to illustrate the effectiveness of the proposed method.

关键词： Energystorage optimization guaranteed output guaranteed rate new energy consumption