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Design and optimization of the RGB beam combiner in micro display using entropy weight-TOPSIS method
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作者 ZHENG Yu ZHAO Yan-bing +4 位作者 ZOU Xin-jie WANG Ji-rong JIANG Xiang LIU Jian-zhe DUAN Ji-an 《Journal of Central South University》 2025年第2期483-494,共12页
Red-green-blue(RGB)beam combiners are widely used in scenarios such as augmented reality/virtual reality(AR/VR),laser projection,biochemical detection,and other fields.Optical waveguide combiners have attracted extens... Red-green-blue(RGB)beam combiners are widely used in scenarios such as augmented reality/virtual reality(AR/VR),laser projection,biochemical detection,and other fields.Optical waveguide combiners have attracted extensive attention due to their advantages of small size,high multiplexing efficiency,convenient mass production,and low cost.An RGB beam combiner based on directional couplers is designed,with a core-cladding relative refractive index difference of 0.75%.The RGB beam combiner is optimized from the perspective of parameter optimization.Using the beam propagation method(BPM),the relationship between the performance of the RGB beam combiner and individual parameters is studied,achieving preliminary optimization of the device’s performance.The key parameters of the RGB beam combiner are optimized using the entropy weight-technique for order preference by similarity to an ideal solution TOPSIS method,establishing the optimal parameter scheme and further improving the device’s performance indicators.The results show that after optimization,the multiplexing efficiencies for red,green,and blue lights,as well as the average multiplexing efficiency,reached 99.17%,99.76%,96.63%and 98.52%,respectively.The size of the RGB beam combiner is 4.768 mm×0.062 mm. 展开更多
关键词 optical waveguide combiners red-green-blue beam combiner beam propagation method entropy weight TOPSIS method multiplexing efficiency
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Investigation on dynamic response of liquid-filled cylindrical shellstructures under the action of combined blast and fragments loading
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作者 Zhujie Zhao Hailiang Hou +4 位作者 Dian Li Xiaowei Wu Yongqing Li Zhenghan Chen Linzhi Wu 《Defence Technology(防务技术)》 2025年第7期334-354,共21页
This study designs four types of liquid-filled cylindrical shell structures to investigate their protection characteristics against explosive shock waves and high-speed fragments.Bare charge and charge-driven prefabri... This study designs four types of liquid-filled cylindrical shell structures to investigate their protection characteristics against explosive shock waves and high-speed fragments.Bare charge and charge-driven prefabricated fragments are employed to examine the damage under blast shock waves and combined blast and fragments loading on various liquid-filled cylindrical shell structures.The test results are compared to numerical calculations and theoretical analysis for the structure's deformation,the liquid medium's movement,and the pressure waves'propagation characteristics under different liquid-filling methods.The results showed that the filling method influences the blast protection and the struc-ture's energy absorption performance.The external filling method reduces the structural deformation,and the internal filling method increases the damage effect.The gapped internal filling method improves the structure's energy absorption efficiency.The pressure wave loading on the liquid-filled cylindrical shell structure differs depending on filling methods.Explosive shock waves and high-speed fragments show a damage enhancement effect on the liquid-filled cylindrical shell structure,depending on the thickness of the internal liquid container layer.The specific impulse on the inner surface of the cylindrical shell positively correlates to the radial deformation of the cylindrical shell structure,and the external liquid layer limits the radial structural deformation. 展开更多
关键词 Blast wave combined blast and fragments loading Filling method Liquid-filled structure Dynamic response
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Combined indirect and direct method for adaptive fuzzy output feedback control of nonlinear system 被引量:2
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作者 Ding Quanxin Chen Haitong +1 位作者 Jiang Changsheng Chen Zongji 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第1期120-124,共5页
A novel control method for a general class of nonlinear systems using fuzzy logic systems (FLSs) is presertted. Indirect and direct methods are combined to design the adaptive fuzzy output feedback controller and a ... A novel control method for a general class of nonlinear systems using fuzzy logic systems (FLSs) is presertted. Indirect and direct methods are combined to design the adaptive fuzzy output feedback controller and a high-gain observer is used to estimate the derivatives of the system output. The closed-loop system is proven to be semiglobally uniformly ultimately bounded. In addition, it is shown that if the approximation accuracy of the fuzzy logic system is high enough and the observer gain is chosen sufficiently large, an arbitrarily small tracking error can be achieved. Simulation results verify the effectiveness of the newly designed scheme and the theoretical discussion. 展开更多
关键词 Nonlinear control systems Non-affine combined indirect and direct method Adaptive fuzzy controller High-gain observer (HGO)
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A Class of Real-Time Parallel Combined Methods ofDigital Simulation for Large Systems
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作者 Liu Degui & Chen Lirong(Beijing Institute of Computer Application and Simulation Technology, 100854, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第2期25-31,共7页
In this paper, a class of real-time parallel combined methods (RTPCM) of the digital simulation for a partitioned large system is presented. By means of combination of the parallelism across the system with the parall... In this paper, a class of real-time parallel combined methods (RTPCM) of the digital simulation for a partitioned large system is presented. By means of combination of the parallelism across the system with the parallelism across the method, stiff and non-stiff subsystems are solved in parallel on parallel computer by a parallel Rosenbrock method and a parallel RK method, respectively. Their construction, convergence and numerical stability are discussed, and the digitalsimulation experiments are conducted. 展开更多
关键词 Large system Real-time parallel combined method Parallel computer
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Class of modified parallel combined methods of real-time numerical simulation for a stiff system
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作者 朱珍民 刘德贵 陈丽容 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第3期387-391,共5页
A class of modified parallel combined methods of real-time numerical simulation are presented for a stiff dynamic system. By combining the parallelism across the system with the parallelism across the method, and rela... A class of modified parallel combined methods of real-time numerical simulation are presented for a stiff dynamic system. By combining the parallelism across the system with the parallelism across the method, and relaxing the dependence of stage value computation on sampling time of input function, a class of modified real-time parallel combined methods are constructed. Stiff and nonstiff subsystems are solved in parallel on a parallel computer by a parallel Rosen-brock method and a parallel RK method, respectively. Their order conditions and convergences are discussed. The numerical simulation experiments show that this class of modified algorithms can get high speed and efficiency. 展开更多
关键词 stiff system real-time numerical simulation parallel combined method.
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Elastoplastic solutions for single piles under combined vertical and lateral loads 被引量:17
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作者 ZHANG Lei GONG Xiao-nan +1 位作者 YANG Zhong-xuan YU Jian-lin 《Journal of Central South University》 SCIE EI CAS 2011年第1期216-222,共7页
In order to improve the reliability of the design and calculation of single piles under the combined vertical and lateral loads, the solutions were presented based on the subgrade reaction method, in which the ultimat... In order to improve the reliability of the design and calculation of single piles under the combined vertical and lateral loads, the solutions were presented based on the subgrade reaction method, in which the ultimate soil resistance was considered and the coefficient of subgrade reaction was assumed to be a constant. The corresponding computational program was developed using FORTRAN language. A comparison between the obtained solutions and the model test results was made to show the validity of the obtained solutions. The calculation results indicate that both the maximum lateral displacement and bending moment increase with the increase of the vertical and lateral loads and the pile length above ground, while decrease as the pile stiffness, the coefficient of subgrade reaction and the yielding displacement of soil increase. It is also shown that the pile head condition controls the pile responses and the vertical load may cause the instability problem to the pile. In general, the proposed method can be employed to calculate the pile responses independent of the magnitude of the pile deflection. 展开更多
关键词 pile-soil interaction combined vertical and lateral loads ultimate resistance subgrade reaction method bendingmoment
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Stability and reliability of pit slopes in surface mining combined with underground mining in Tonglushan mine 被引量:10
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作者 罗一忠 吴爱祥 +1 位作者 刘湘平 王洪江 《Journal of Central South University of Technology》 EI 2004年第4期434-439,共6页
Slope stability is of critical importance in the process of surface-underground mining combination. The influence of underground mining on pit slope stability was mainly discussed, and the self-stabilization of underg... Slope stability is of critical importance in the process of surface-underground mining combination. The influence of underground mining on pit slope stability was mainly discussed, and the self-stabilization of underground stopes was also studied. The random finite element method was used to analyze the probability of the rock mass stability degree of both pit slopes and underground stopes. Meanwhile, 3D elasto-plastic finite element method was used to research into the stress, strain and rock mass failure resulting from mining. The results of numerical simulation indicate that the mining of the underground test stope has certain influence on the stability of the pit slope, but the influence is not great. The safety factor of pit slope is decreased by 0.06, and the failure probability of the pit slope is increased by 1.84%. In addition, the strata yielding zone exists around the underground test stope. The results basically conform to the information coming from the field monitoring. 展开更多
关键词 surface-underground mining combination STABILITY RELIABILITY random finite element method (numerical simulation)
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Optimization principle of combined surface and underground mining and its applications 被引量:3
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作者 陈建宏 古德生 李建雄 《Journal of Central South University of Technology》 2003年第3期222-225,共4页
The pit limit optimization is discussed, which is one of the most important problems in the combined min-ing method, on the basis of the economic model of ore-blocks. A new principle of the limit optimization is put f... The pit limit optimization is discussed, which is one of the most important problems in the combined min-ing method, on the basis of the economic model of ore-blocks. A new principle of the limit optimization is put for-ward through analyzing the limitations of moving cone method under such conditions. With a view to recovering asmuch mineral resource as possible and making the maximum profit from the whole deposit, the new principle is tomaximize the sum of gain from both open-pit and underground mining. The mathematical models along the horizon-tal and vertical directions and modules for software package (DM&MCAD) have been developed and tested inTonglushan Copper Mine. It has been proved to be rather effective in the mining practice. 展开更多
关键词 surface MINING UNDERGROUND MINING combined MINING method OPTIMIZATION MODEL open PIT limit block economic MODEL
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Nonlinear combined forecasting model based on fuzzy adaptive variable weight and its application 被引量:1
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作者 蒋爱华 梅炽 +1 位作者 鄂加强 时章明 《Journal of Central South University》 SCIE EI CAS 2010年第4期863-867,共5页
In order to enhance forecasting precision of problems about nonlinear time series in a complex industry system,a new nonlinear fuzzy adaptive variable weight combined forecasting model was established by using concept... In order to enhance forecasting precision of problems about nonlinear time series in a complex industry system,a new nonlinear fuzzy adaptive variable weight combined forecasting model was established by using conceptions of the relative error,the change tendency of the forecasted object,gray basic weight and adaptive control coefficient on the basis of the method of fuzzy variable weight.Based on Visual Basic 6.0 platform,a fuzzy adaptive variable weight combined forecasting and management system was developed.The application results reveal that the forecasting precisions from the new nonlinear combined forecasting model are higher than those of other single combined forecasting models and the combined forecasting and management system is very powerful tool for the required decision in complex industry system. 展开更多
关键词 nonlinear combined forecasting nonlinear time series method of fuzzy adaptive variable weight relative error adaptive control coefficient
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Combination Method for Parallel Computation in ODEs
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作者 Song Xiaoqiu(Beijing Institute of Computer Application and Simulation Technology ) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1996年第4期19-26,共8页
In this paper, a 3rd order combination method with three processes and a 4th order combination method with five processes for solving ODEs are discussed. These methods are the Runge-Kutta method combined with a linear... In this paper, a 3rd order combination method with three processes and a 4th order combination method with five processes for solving ODEs are discussed. These methods are the Runge-Kutta method combined with a linear multistep method, which overcomes the defect of the 3rd order parallel Runge-Kutta method discussed in [1]. 展开更多
关键词 SOFTWARE RELIABILITY Numerical analysis combination method Parallel Computation ODEs.
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Reliability sensitivity analysis based on multi-hyperplane combination method 被引量:1
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作者 Yu-ge DONG Hai-tao LU Ling-ling LI 《Defence Technology(防务技术)》 SCIE EI CAS 2014年第4期354-359,共6页
For a nonlinear limit state function, the first-order reliability method(FORM) may cause large errors in the computation of not only the reliability index or failure probability but also the reliability sensitivity. I... For a nonlinear limit state function, the first-order reliability method(FORM) may cause large errors in the computation of not only the reliability index or failure probability but also the reliability sensitivity. In order to obtain more the accurate results of the reliability sensitivity analysis, a number of hyperplanes are built near the design point by first-order Tayler series expansion, which replace the known nonlinear limit state hypersurface, and an equivalent computational method is utilized to construct an equivalent hyperplane of the obtained hyperplanes. And the reliability sensitivities can be estimated more accurately by the derived equations based on the equivalent hyperplane. An example shows that the method is effective and feasible. 展开更多
关键词 可靠性指标 灵敏度分析 超平面 极限状态函数 可靠性灵敏度 泰勒级数展开 可靠度方法 失效概率
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煤矿深部巷道大变形分步联合控制研究 被引量:4
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作者 李培涛 刘泉声 +2 位作者 朱元广 高峰 范利丹 《岩土力学》 北大核心 2025年第2期591-612,共22页
深部巷道大变形已成为深部煤炭安全高效开采的关键制约因素。为实现深部软弱围岩稳定性控制,提出了基于深部巷道大变形演化过程的分步联合支护方案及其理论分析模型。结果表明,深部软弱围岩呈破裂碎胀变形-损伤扩容变形-连续变形的分布... 深部巷道大变形已成为深部煤炭安全高效开采的关键制约因素。为实现深部软弱围岩稳定性控制,提出了基于深部巷道大变形演化过程的分步联合支护方案及其理论分析模型。结果表明,深部软弱围岩呈破裂碎胀变形-损伤扩容变形-连续变形的分布特征。分步联合支护后,围岩极限承载力随锚杆和锚索等效支护力增大呈线性增大趋势,但随注浆修复系数呈指数增大趋势。锚杆和锚索支护设计时应以极限承载力所需的注浆修复系数等于1.0时的等效支护力临界条件为基准。深浅孔注浆支护时须同时考虑注浆修复系数和围岩破裂区半径。不同支护措施的协同支护参数可由破裂修复区围岩极限承载平衡条件确定。数值模拟和工程应用分析表明,分步联合支护可实现深部软弱围岩碎胀大变形控制,具有较高的工程推广应用价值。 展开更多
关键词 深部软弱围岩 大变形 分步联合支护 承载平衡 协同控制
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基于组合赋权和物元可拓模型的东北河流健康评价 被引量:1
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作者 张媛媛 刘建卫 +1 位作者 逄晓腾 王明玮 《中国农村水利水电》 北大核心 2025年第2期31-36,44,共7页
为构建适用于东北地区的河流健康评价体系,针对东北河流特殊的季节性冰封水文特征,以及传统评价体系的应用局限性,如未给予水文指标合理的权重和解释,评价结果难以体现河流健康发展趋势等问题。基于《河湖健康评估技术导则(SL/T793-2020... 为构建适用于东北地区的河流健康评价体系,针对东北河流特殊的季节性冰封水文特征,以及传统评价体系的应用局限性,如未给予水文指标合理的权重和解释,评价结果难以体现河流健康发展趋势等问题。基于《河湖健康评估技术导则(SL/T793-2020)》,结合东北河流的水文、生态和社会服务功能等多维特征进行评价体系及方法改进,并以拉林河、第二松花江、伊通河、饮马河、东辽河等东北典型河流作为研究对象,通过采用组合赋权和物元可拓模型的方法,对各河流的健康等级进行量化评价,并利用综合关联度距离预测了河流健康水平的未来发展趋势。结果显示,改进后的东北河流健康评价体系共包含水文、水环境、河岸物理结构、水生生物以及社会服务功能5个状态层16项评价指标,能够基本适应东北河流的健康评价需求;健康评价结果得到伊通河最大综合关联度为0.014 6,健康等级为IV级,处于“不健康”状态,其余河流均处于“亚健康”状态(III级),且健康状态呈好转趋势。这一结论在综合指数法和模糊评价模型中得到了验证,能够为东北河流的持续健康管理提供科学依据,同时,也为类似寒冷地区的河流健康评估和管理提供了参考。 展开更多
关键词 河流健康 指标体系 组合赋权法 物元可拓
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基于栅格信息量法的区域地面沉降风险评价——以河北省沧州市为例 被引量:1
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作者 刘波 李诗浓 +3 位作者 李伟 王文鹏 鲁程鹏 束龙仓 《吉林大学学报(地球科学版)》 北大核心 2025年第3期919-929,共11页
地面沉降风险诱发因素复杂、空间分布差异较大,为科学开展地面沉降风险评估工作,本研究提出栅格信息量法的地面沉降风险评价方法。首先通过计算各栅格化评价指标与地表形变量之间的信息量值,定量表征两者之间的关联程度;然后构建包含危... 地面沉降风险诱发因素复杂、空间分布差异较大,为科学开展地面沉降风险评估工作,本研究提出栅格信息量法的地面沉降风险评价方法。首先通过计算各栅格化评价指标与地表形变量之间的信息量值,定量表征两者之间的关联程度;然后构建包含危险性、脆弱性和暴露度3个方面共11项指标的评价体系;再采用主客观综合赋权方法确定权重并计算风险值,通过受试者工作特征曲线进行的可靠性检验后进行风险评价;最后将上述方法应用于2022年河北省沧州市地面沉降风险评价。结果表明:相较于脆弱性评价指标,危险性和暴露度评价指标的栅格信息量值偏高。危险性评价指标中,年平均地面沉降速率为高风险指标,当年平均地面沉降速率为-127~-17 mm/a时,信息量值为1.538,对地面沉降风险的危险性最大;暴露度评价指标中,人口密度为高风险指标,当人口密度>5430人/km^(2)时,信息量值为1.923,对地面沉降风险的暴露度最高。沧州市1 km空间分辨率下地面沉降风险等级为高、较高、中、较低、低五个等级的区域面积占比分别为9.90%、24.91%、31.12%、23.05%、11.02%;高风险区主要集中在沧州市主城区、肃宁县、黄骅市等区域,中风险地区主要分布于沧州市西部区域。栅格信息量法对沧州市地面沉降风险评价的可靠性较好,准确度达到0.714。 展开更多
关键词 风险评价 栅格信息量法 地面沉降 主客观组合赋权 河北省沧州市
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联合净化法结合高效液相色谱-串联质谱同时测定鸽蛋中5类24种兽药残留 被引量:1
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作者 张静 马丽娜 +6 位作者 刘茵茵 周倩 唐修君 陆俊贤 樊艳凤 赵敏 高玉时 《中国家禽》 北大核心 2025年第2期105-112,共8页
为建立一种可同时检测鸽蛋中多类兽药残留的高通量液相色谱-串联质谱法,试验采用正己烷去脂,联合QuEChERS净化结合冷冻脂质过滤法,建立检测鸽蛋中5类24种兽药残留的高效液相色谱-串联质谱法。样品中的5类兽药(氯霉素类、磺胺类、硝基咪... 为建立一种可同时检测鸽蛋中多类兽药残留的高通量液相色谱-串联质谱法,试验采用正己烷去脂,联合QuEChERS净化结合冷冻脂质过滤法,建立检测鸽蛋中5类24种兽药残留的高效液相色谱-串联质谱法。样品中的5类兽药(氯霉素类、磺胺类、硝基咪唑类、喹诺酮类和抗病毒类)经1.0%乙酸乙腈溶液提取,氮气吹干,冷冻过夜后,结合QuEChERS净化和正己烷去脂,采用1 mL 0.1%甲酸水-乙腈溶液(v/v,90∶10)复溶;高效液相色谱-串联质谱测定,内标法定量,采用实际样品建立方法的初步应用。结果显示:24种兽药在2.0~200 ng/mL线性关系良好(R2>0.99),该方法的定量限为2μg/kg,平均回收率为62.2%~117.1%,相对标准偏差4.3%~18.9%;实际样品检出的7种目标化合物与标准方法相比的相对标准偏差为1.34%~5.20%。研究表明,建立的检测鸽蛋中多类兽药残留的高通量液相色谱-串联质谱法省去固相萃取步骤,成本较低,灵敏高效,回收率优良、重复性稳定,适用于鸽蛋中多类兽药的快速监测分析。 展开更多
关键词 联合净化法 高效液相色谱-串联质谱 QUECHERS 兽药残留 鸽蛋
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数字经济赋能下经济高质量发展的动态评价研究——基于时间加权最优组合赋权法 被引量:1
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作者 王韶华 杨志葳 +1 位作者 张伟 王菲 《运筹与管理》 北大核心 2025年第1期207-213,I0086,共7页
实现高质量发展是中国式现代化的本质要求之一,在实现经济高质量发展的过程中,数字经济大有可为。基于经济高质量发展的内涵及理论分析,构建涵盖传统供给侧因素、供给侧数字化、传统需求侧因素和需求侧数字化的经济高质量发展评价指标... 实现高质量发展是中国式现代化的本质要求之一,在实现经济高质量发展的过程中,数字经济大有可为。基于经济高质量发展的内涵及理论分析,构建涵盖传统供给侧因素、供给侧数字化、传统需求侧因素和需求侧数字化的经济高质量发展评价指标体系。运用包含层次分析法、熵权法、CRITIC权重法和独立性权重法的最优组合赋权法确定时变指标权重,并引入时间加权向量对其进行改进,消除时间属性,计算时间加权组合权重。在此基础上,对我国2013—2019年30省市的经济高质量发展水平进行评价,并采用多种手段对其时空演变进行分析。结果表明:传统供给侧和传统需求侧是影响经济高质量发展的前两大因素,需求侧数字化逐步超越供给侧数字化,成为影响经济高质量发展的第三大因素;我国数字经济发展水平实现了整体跃迁,其中西南地区发展亮眼;经济高质量发展存在较大的区域异质性,北部沿海、东部沿海、南部沿海和长江中游地区是我国经济高质量发展的四个极点。实证评价结果为进一步推动我国经济高质量发展提供参考和借鉴。 展开更多
关键词 经济高质量发展 数字经济 动态评价 时间加权最优组合赋权法
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基于两种染色法联用的混合浆纸纤维识别方法的研究
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作者 芮金生 徐如彦 +3 位作者 闫新可 王悦悦 朱成文 任浩 《林产化学与工业》 北大核心 2025年第4期105-113,共9页
基于Herzberg和Graff“C”两种染色剂的特点和工作原理,探索了不同染色剂质量分数、温度和染色时间对针叶材、阔叶材和麻浆纤维染色结果差异性的影响,通过系统调整染色剂质量分数(100%、92%、90%、80%)、温度(10~50℃)和时间(10~40 s)... 基于Herzberg和Graff“C”两种染色剂的特点和工作原理,探索了不同染色剂质量分数、温度和染色时间对针叶材、阔叶材和麻浆纤维染色结果差异性的影响,通过系统调整染色剂质量分数(100%、92%、90%、80%)、温度(10~50℃)和时间(10~40 s)成功建立了一种简单高效的鉴别混合浆纤维组成的方法。发现通过调整染色剂质量分数可以逐步实现对麻浆和阔叶材纤维的最为显著的识别效果,针叶材纤维可通过颜色的深浅程度判断其存在与否。当Herzberg染色剂稀释到标准染色剂的90%,染色20 s时可识别混合浆中麻浆纤维;Graff“C”染色剂稀释到标准染色剂的90%,染色30 s时可识别阔叶材纤维。通过单因素试验可得:染色剂的质量分数对染色结果影响最大,且相同质量分数下的染色时间和染色温度对染色效果影响不显著。在最佳染色工艺条件下,对5种商品卷烟纸样(S1~S5)进行了鉴定,确认在不同的时间、温度等环境条件下建立的识别方法可以有效分辨纤维种类,且具有高度的稳定性。 展开更多
关键词 染色法联用 混合浆 定性识别
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地下水背景值评估研究进展
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作者 闫纲丽 冯屾 +1 位作者 刘睿男 黄冠星 《吉林大学学报(地球科学版)》 北大核心 2025年第5期1655-1670,共16页
选取适宜的地下水背景值评估方法是客观认知地下水背景值的关键。本文在回顾地下水背景值研究发展历程的基础上,概述了现有评估方法及其优缺点,并指出其未来发展趋势。地下水背景值评估方法大致可分为基于未被污染地下水样本的方法、预... 选取适宜的地下水背景值评估方法是客观认知地下水背景值的关键。本文在回顾地下水背景值研究发展历程的基础上,概述了现有评估方法及其优缺点,并指出其未来发展趋势。地下水背景值评估方法大致可分为基于未被污染地下水样本的方法、预筛选法、数理统计法、基于图谱的探索性数据分析方法及多方法组合等五类。其中:基于未被污染地下水样本的方法因其自身局限性较强已很少采用;预筛选法和数理统计法是当前常用单一类方法,前者主观性较强而后者客观性更优;基于图谱的探索性数据分析方法少见单独使用,多与其他方法组合联用;多方法组合通过互补单一方法的局限性已经成为地下水背景值评估研究的重要发展方向。多方法组合中:预筛选-数理统计组合方法最常见,应用较广;新兴的基于图谱的探索性数据分析方法与预筛选法、数理统计法或预筛选-数理统计法三种方法中的其中一种分别组合的方法更为优越,但该类组合方法的使用往往需要以研究区水文地球化学的深入认知为基础,便捷性和普适性不如预筛选-数理统计组合方法。多方法组合已成为地下水背景值评估研究的主要发展趋势。 展开更多
关键词 地下水 背景值 预筛选法 数理统计法 基于图谱的探索性数据分析 组合方法
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组合载荷作用下加筋板极限强度相互关系公式
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作者 万琪 宋召军 +2 位作者 钱伟 杨鑫 李晓彬 《船舶力学》 北大核心 2025年第2期277-287,共11页
船舶航行时整体船体梁受到货物装载载荷、船底吃水静水弯矩与波浪弯矩等组合载荷联合作用,而其局部船体加筋板结构则承受面内纵向、横向与面外压力载荷等三向载荷联合作用。侧向载荷的大小不同程度地影响加筋板面内的纵向与横向承载能力... 船舶航行时整体船体梁受到货物装载载荷、船底吃水静水弯矩与波浪弯矩等组合载荷联合作用,而其局部船体加筋板结构则承受面内纵向、横向与面外压力载荷等三向载荷联合作用。侧向载荷的大小不同程度地影响加筋板面内的纵向与横向承载能力,故需建立组合载荷共同加载条件下的加筋板极限强度相互关系式。本文以散货轮船底结构为研究对象,采用对称循环边界的双跨双弯几何范围加筋板模型,应用非线性有限元法分析实船连续船体结构遭受横向、纵向与侧向等组合载荷联合作用时的极限强度相互影响规律。通过研究发现,通常侧向载荷降低加筋板结构纵向与横向极限承载力,且板柔度越小则降低越大,同时建议分别通过增大型材尺寸与板材厚度提高侧压作用下的纵向与横向极限承载力,并提出组合载荷联合作用下的加筋板极限强度相互关系表达式。该方法可评估纵向、横向与侧向载荷联合作用下的极限强度相互关系,以开展复合载荷状态下的船舶加筋板结构强度设计的快速评估。 展开更多
关键词 组合载荷 加筋板 极限强度 数值仿真 相互公式
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G1-CRITIC-VIKOR模型在山区干线公路交通安全评价中的应用研究 被引量:1
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作者 王立 李智俣 +3 位作者 何瑞春 王治利 徐重岐 赵冬 《安全与环境学报》 北大核心 2025年第5期1666-1674,共9页
为克服单一赋权法的局限性,结合山区干线公路交通特征及交通安全评价指标的选取原则,从社会因素、驾驶因素、环境因素、管理因素和道路因素五个维度出发,选取18个综合评价指标,运用序关系分析法(Order Relation Analysis Method,G1)-指... 为克服单一赋权法的局限性,结合山区干线公路交通特征及交通安全评价指标的选取原则,从社会因素、驾驶因素、环境因素、管理因素和道路因素五个维度出发,选取18个综合评价指标,运用序关系分析法(Order Relation Analysis Method,G1)-指标相关性权重确定法(Criteria Importance Through Intercriteria Correlation,CRITIC)确定各评价指标的权重,并结合折中妥协多属性决策法(VlseKriterijumska Optimizacija I Kompromisno Resenje,VIKOR)对山区干线公路交通安全进行综合评价,提出了基于G1-CRITIC-VIKOR模型的山区干线公路交通安全综合评价及比选方法。以中国西部6条山区干线公路为例进行实证研究,结果表明,G1-CRITIC-VIKOR模型的评价效果与传统的秩和比(Rank-Sum Ratio,RSR)综合评价法及加权逼近理想解排序法(Technique for Order Preference by Similarity to Ideal Solution,TOPSIS)的评价结果基本一致,且评价效果明显优于后者,具有更好的辨识性,验证了该模型的可行性和科学性。 展开更多
关键词 安全工程 交通安全评价 山区干线公路 组合赋权 秩和比法 加权逼近理想解排序法
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