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Geological Hazard Susceptibility Assessment in Shouning County Based on Information Quantity Method
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作者 ZHANG Min CHEN Jiai +2 位作者 CHEN Zhefeng ZHENG Zhe XUE Chengzhi 《Journal of Geodesy and Geoinformation Science》 2025年第3期70-91,共22页
This study develops a geological hazard evaluation index system for Shouning County,a key area for disaster prevention in Fujian Province.Through detailed investigation reports and field surveys,six factors were selec... This study develops a geological hazard evaluation index system for Shouning County,a key area for disaster prevention in Fujian Province.Through detailed investigation reports and field surveys,six factors were selected,including elevation,slope gradient,slope aspect,stratigraphic lithological group,distance from the water systems,and geological structures.A geological hazard susceptibility zoning map was created using the Information Quantity Method(IQM).The evaluation showed that elevation,slope aspect,and distance from the water systems are primary risk factors,with high and extremely high susceptibility areas covering 168.57 km^(2)(52.63%of the study area)and a disaster point density of 3.07 points/km^(2).The model achieved an accuracy of 0.73,validating its effectiveness in hazard assessment.These findings provide a valuable reference for disaster prediction and mitigation in Shouning County,supporting improved planning and risk management efforts. 展开更多
关键词 Shouning County geological hazards information quantity method susceptibility evaluation
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Objective Model Selection in Physics: Exploring the Finite Information Quantity Approach
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2024年第5期1848-1889,共42页
Traditional methods for selecting models in experimental data analysis are susceptible to researcher bias, hindering exploration of alternative explanations and potentially leading to overfitting. The Finite Informati... Traditional methods for selecting models in experimental data analysis are susceptible to researcher bias, hindering exploration of alternative explanations and potentially leading to overfitting. The Finite Information Quantity (FIQ) approach offers a novel solution by acknowledging the inherent limitations in information processing capacity of physical systems. This framework facilitates the development of objective criteria for model selection (comparative uncertainty) and paves the way for a more comprehensive understanding of phenomena through exploring diverse explanations. This work presents a detailed comparison of the FIQ approach with ten established model selection methods, highlighting the advantages and limitations of each. We demonstrate the potential of FIQ to enhance the objectivity and robustness of scientific inquiry through three practical examples: selecting appropriate models for measuring fundamental constants, sound velocity, and underwater electrical discharges. Further research is warranted to explore the full applicability of FIQ across various scientific disciplines. 展开更多
关键词 Comparative Uncertainty Finite information quantity Formulating a Model Measurement Accuracy Limit Objective Model Selection
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The remote sensing composite information entropy and types of Nansha coral reef atolls
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作者 刘宝银 王岩峰 +1 位作者 高俊国 郝庆祥 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1999年第3期389-400,共12页
In the viempint that the coral reef atolls' growth index of the Nansha Islands is influenced by many factors, the measured remote sensing comopite information including some mutually related factors is divided int... In the viempint that the coral reef atolls' growth index of the Nansha Islands is influenced by many factors, the measured remote sensing comopite information including some mutually related factors is divided into 10 geographic events as N1, N2 ..., N10, and the analysis of the atolls' information entropy is made. From the value of theentropy, the closed related factors with the index of the emerged atolls are shown. In proper order, the factors are reeftop's area(0. 319), lagoon's area(0. 324), open-degree of atoll(0. 336), trend of atoll(0. 551 ). On the basis of thiswork, a new description function of the emerged atoll growth index is proposed. This function can be used to identifythe open my of Nansha atoll growth. 展开更多
关键词 Nansha Islands remote sensing information information entropy growth index atoll's types
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Quantity discount contracts for supply chain coordination under asymmetric information and disruptions
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作者 Zhuang, Pin Zhao, Lindu 《Journal of Southeast University(English Edition)》 EI CAS 2008年第S1期11-16,共6页
The quantity discount contracts are investigated for a one-supplier-one-retailer supply chain with asymmetric information when the retailer's cost is disrupted. While the retailer's cost structure is asymmetri... The quantity discount contracts are investigated for a one-supplier-one-retailer supply chain with asymmetric information when the retailer's cost is disrupted. While the retailer's cost structure is asymmetric information, two all-unit quantity discount contract models, fixed expected-profit percentage discount(FEPD) and fixed wholesale-pricing percentage discount(FWPD) under asymmetric information are proposed in a regular scenario. When the retailer's cost distribution fluctuates due to disruptions, the optimal emergency strategies of supply chains are obtained under asymmetric information. Using numerical methods, the impact of cost disruptions on decisions about the regular wholesale price, discount wholesale price, order quantity and expected profits of the retailer, the supplier as well as the total system are analyzed. It is found that the FEPD policy is more robust and adaptable than the FWPD policy in disruption circumstances. 展开更多
关键词 supply chain quantity discount disruption management asymmetric information
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Quantity Discount Scheme in Supply Chain under Asymmetric Information
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作者 厉吉斌 彭作和 《Journal of Southwest Jiaotong University(English Edition)》 2007年第2期166-171,共6页
Quantity discount scheme plays an important role in supply chain management. The different quantity discount schemes under symmetric (full) information and asymmetric information, are analyzed by using principal-age... Quantity discount scheme plays an important role in supply chain management. The different quantity discount schemes under symmetric (full) information and asymmetric information, are analyzed by using principal-agent and optimal control theory. As a result, the research reveals that the optimal quantity discount solution under symmetric information is a special case of that under asymmetric information. At the same price, the critical value of quantity discount under asymmetric information is much lower than that under asymmetric information. Therefore, this leads to less cost for retailers and smaller profit for their supplier. 展开更多
关键词 Supply chain management quantity discount Asymmetric information Optimal control
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ON INFORMATION THEORY METHOD FOR RELIABILITY ASSESSMENT OF SYSTEMS CONSISTING OF DIFFERENT SUCCESS FAILURE MODEL UNITS 被引量:1
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作者 孙有朝 施军 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第2期129-133,共5页
Using the characteristic of addition of information quantity and the principle of equivalence of information quantity, this paper derives the general conversion formulae of the formation theory method conversion (synt... Using the characteristic of addition of information quantity and the principle of equivalence of information quantity, this paper derives the general conversion formulae of the formation theory method conversion (synthesis) on the systems consisting of different success failure model units. According to the fundamental method of the unit reliability assessment, the general models of system reliability approximate lower limits are given. Finally, this paper analyses the application of the assessment method by examples, the assessment results are neither conservative nor radical and very satisfactory. The assessment method can be popularized to the systems which have fixed reliability structural models. 展开更多
关键词 information theory information quantity success failure model units reliability assessment approximate lower limit
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基于景观形状指数与图斑质心距离特征的土地覆盖数据空间信息测量方法
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作者 罗思龙 周晓光 +2 位作者 侯东阳 赵绍轩 王岚 《地球信息科学学报》 北大核心 2026年第1期222-242,共21页
【目的】土地覆盖产品是传递空间信息的重要数据载体之一,测量与评估其信息含量是地图信息论研究的基础理论。现有香农熵或玻尔兹曼熵在度量土地覆盖数据中的信息内容存在局限性:香农熵主要基于图像中统计特征度量非空间组成信息,难以... 【目的】土地覆盖产品是传递空间信息的重要数据载体之一,测量与评估其信息含量是地图信息论研究的基础理论。现有香农熵或玻尔兹曼熵在度量土地覆盖数据中的信息内容存在局限性:香农熵主要基于图像中统计特征度量非空间组成信息,难以有效表征图像中的空间信息含量;空间熵及一些景观指数虽然能够反映出图像的空间结构特征,但其度量数值与空间结构的无序程度无关,不具有热力学一致性;源于热力学的玻尔兹曼熵虽然能刻画图像的空间结构无序程度,但测量的图像结构信息属于多种空间信息的综合反映,无法精确表达地物几何形状与空间分布等信息成分的含量。【方法】基于地图学对图像信息本质的认知,本文将几何形状与空间分布作为图像空间信息测量的主要成分,提出一种基于景观形状指数与图斑质心距离特征的土地覆盖数据空间信息测量方法。首先,依据土地覆盖数据中的类别体系,构建各个要素类别的几何形状和空间分布特征指标;然后基于特征信息度量模型,测量各要素的几何形状信息与空间分布信息含量;最终基于要素面积加权融合获得图像整体的空间信息含量。【结果】基于AID影像分类数据及其模拟图像进行多组实验,将本文方法与香农熵、空间熵、玻尔兹曼熵及景观指数进行对比,结果表明:本方法能够显著区分不同土地覆盖数据的空间信息差异,测量结果符合人们的空间认知。同时,该方法不仅可以精确刻画图像的几何形状与空间分布特征,而且在表征图像空间无序度方面具有与现有玻尔兹曼熵相当的热力学一致性,相关系数达到0.93。进一步应用于武汉与长沙市两地2010—2020年真实土地覆盖数据产品,结果显示两地区整体综合信息量分别提高约19%与35%。【结论】本文方法有助于精确测量土地覆盖数据的几何形状以及空间分布特征的信息含量,为图像信息量化及其在土地覆盖变化及城市扩张等实践应用中提供一种新的理论工具。 展开更多
关键词 土地覆盖 空间信息 信息量 几何形状 空间分布 空间结构 无序度
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Unleashing the Power of Information Theory: Enhancing Accuracy in Modeling Physical Phenomena 被引量:1
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2023年第3期760-779,共20页
When building a model of a physical phenomenon or process, scientists face an inevitable compromise between the simplicity of the model (qualitative-quantitative set of variables) and its accuracy. For hundreds of yea... When building a model of a physical phenomenon or process, scientists face an inevitable compromise between the simplicity of the model (qualitative-quantitative set of variables) and its accuracy. For hundreds of years, the visual simplicity of a law testified to the genius and depth of the physical thinking of the scientist who proposed it. Currently, the desire for a deeper physical understanding of the surrounding world and newly discovered physical phenomena motivates researchers to increase the number of variables considered in a model. This direction leads to an increased probability of choosing an inaccurate or even erroneous model. This study describes a method for estimating the limit of measurement accuracy, taking into account the stage of model building in terms of storage, transmission, processing and use of information by the observer. This limit, due to the finite amount of information stored in the model, allows you to select the optimal number of variables for the best reproduction of the observed object and calculate the exact values of the threshold discrepancy between the model and the phenomenon under study in measurement theory. We consider two examples: measurement of the speed of sound and measurement of physical constants. 展开更多
关键词 Finite information quantity International System of Units MODELLING Physical Constant Speed of Sound
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基于改进遗传算法的电力数字化故障检测研究
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作者 谢振刚 卢建生 +3 位作者 王超 杨子成 梁玥 郭海旭 《信息技术》 2026年第2期136-140,共5页
电力系统中的监测数据受到测量误差、传感器噪声以及通信干扰等因素的影响,数据质量可能不稳定。数据中的噪声和异常值给故障检测带来了困难。为此,文中提出基于改进遗传算法的电力数字化故障检测方法。提取电力负荷异常数据,建立有故... 电力系统中的监测数据受到测量误差、传感器噪声以及通信干扰等因素的影响,数据质量可能不稳定。数据中的噪声和异常值给故障检测带来了困难。为此,文中提出基于改进遗传算法的电力数字化故障检测方法。提取电力负荷异常数据,建立有故障和无故障情况下的结构转移矩阵;获取电力故障信息特征量,识别和提取故障信号中的关键特征量,实现电力数字化故障的检测。应用多种群遗传算法对故障检测结果完成校正。实验结果显示:对于电流故障、电压故障、功率故障以及负荷波形故障的检测,研究方法的误差始终低于1.0%,且F1得分接近1。 展开更多
关键词 改进遗传算法 电力数字化故障 电力负荷 信息特征量 误差校正
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基于自我调节常识理论模型的2型糖尿病患者健康信息寻求行为现状及影响因素分析
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作者 何文苡 李琦 +1 位作者 李玉玲 李薇 《中国实用护理杂志》 2026年第6期423-432,共10页
目的基于自我调节常识理论模型了解2型糖尿病患者健康信息寻求行为的现状、相关影响因素以及作用路径,为健康信息宣传优化政策提供依据。方法采用便利抽样法选取2024年6—12月于广东省第二中医院内分泌科就诊的2型糖尿病患者为调查对象... 目的基于自我调节常识理论模型了解2型糖尿病患者健康信息寻求行为的现状、相关影响因素以及作用路径,为健康信息宣传优化政策提供依据。方法采用便利抽样法选取2024年6—12月于广东省第二中医院内分泌科就诊的2型糖尿病患者为调查对象。采用一般资料调查表、健康信息寻求行为量表、糖尿病管理自我效能量表、病人自我管理任务感知和支持需求问卷进行横断面调查。结果共发放256份问卷,回收248份有效问卷,有效回收率为96.88%。248例患者中男139例,女109例,年龄为(59.96±11.40)岁。2型糖尿病患者健康信息寻求行为、糖尿病管理自我效能、自我管理任务感知和自我管理支持需求得分分别为(3.55±0.54)、(121.71±30.51)、(34.93±9.14)、(28.98±11.41)分;患者健康信息寻求行为的主要影响因素包括年龄、受教育程度、糖尿病病程、住院次数以及糖尿病管理自我效能、自我管理任务感知和自我管理支持需求(t值为-5.47~7.37,均P<0.05);健康信息寻求行为与糖尿病管理自我效能、自我管理任务感知呈正相关(r=0.558、0.730,均P<0.05),与自我管理支持需求呈负相关(r=-0.469,P<0.05);自我管理任务感知和自我管理支持需求在糖尿病管理自我效能和健康信息寻求行为之间均起部分中介作用,效应值分别为0.196、0.037(均P<0.05);其中以自我管理任务感知的中介效应更强,而自我管理支持需求作用相对有限。自我管理任务感知的中介效应占比为46.23%。结论2型糖尿病患者的健康信息寻求行为水平一般,既受到自我效能的直接影响,也通过自我管理任务感知和自我管理支持需求发挥中介作用;据此,未来在临床实践中需要帮助患者明确自我管理任务,为其自我管理提供标准化支持,针对其健康信息寻求行为特点提供个性化护理方案,有效转化临床效益。 展开更多
关键词 糖尿病 2型 健康信息寻求行为 自我调节常识模型 影响因素分析
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基于元路径和边类型增强的异质图神经网络模型
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作者 郑子昂 孙丽萍 +2 位作者 任威 王赛奇 丁伟 《微电子学与计算机》 2026年第1期124-132,共9页
在异质信息网络中,常用元路径来描述不同实体之间的关系。现有的异质图神经网络模型,也常基于元路径来捕获异质信息网络中的复杂关系。除此以外,还涌现出了抛弃元路径转而使用边类型信息的方法来重新表示实体之间的关系。然而,这些方法... 在异质信息网络中,常用元路径来描述不同实体之间的关系。现有的异质图神经网络模型,也常基于元路径来捕获异质信息网络中的复杂关系。除此以外,还涌现出了抛弃元路径转而使用边类型信息的方法来重新表示实体之间的关系。然而,这些方法过度依赖元路径或边类型,未能充分利用元路径和边类型的协同潜力。因此,提出了一种新型的异质图神经网络模型HGME,首次将元路径与边类型信息同时融合,通过元路径和边类型增强的方法协同处理异质信息网络中实体之间的关系。在ACM、DBLP、 Freebase这3个异质网络数据集中进行了实验。实验结果表明:HGME模型在3种数据集的分类和聚类任务中,均优于传统的异质图神经网络模型。通过可视化分析,进一步证实了HGME的有效性。 展开更多
关键词 异质信息网络 图神经网络 元路径 边类型
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SIRT5介导的PKM2对香烟烟雾提取物诱导的巨噬细胞极化的影响及其作用机制
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作者 崔萌萌 徐丹 李风森 《新疆医科大学学报》 2026年第1期9-15,共7页
目的 观察沉默信息调节因子5(Silent information regulator 5,SIRT5)介导的丙酮酸激酶M2受体(Pyruvate kinase type 2,PKM2)通过调节巨噬细胞极化对香烟烟雾诱导的炎症水平的影响,探讨其可能存在的作用机制。方法 以小鼠巨噬细胞为研... 目的 观察沉默信息调节因子5(Silent information regulator 5,SIRT5)介导的丙酮酸激酶M2受体(Pyruvate kinase type 2,PKM2)通过调节巨噬细胞极化对香烟烟雾诱导的炎症水平的影响,探讨其可能存在的作用机制。方法 以小鼠巨噬细胞为研究对象,香烟烟雾提取物(Cigarette smoke extract, CSE)作为刺激因素,诱导体外炎症模型,分为空白对照组(正常培养RAW264.7细胞,不进行任何干预)、CSE干预组(培养细胞,并进行CSE干预)、SIRT5-NC组(CSE干预细胞,只用于感染过程中的对照)、SIRT5-siRNA-2组(CSE干预细胞,转染SIRT5-siRNA)和SIRT5-siRNA-2+OE-PKM2组(CSE干预细胞,转染SIRT5-siRNA后,加入PKM2激动剂)。实时荧光定量逆转录聚合酶链式反应(RT-qPCR)检测SIRT5及PKM2 mRNA的表达。蛋白质印迹(Western blot)法检测各组细胞模型SIRT5和PKM2的蛋白表达。流式细胞术检测各组细胞M1、M2型巨噬细胞表型分布。酶联免疫吸附测定(ELISA)法检测细胞上清中白细胞介素-6(Interleukin-6,IL-6)、IL-10、IL-12和肿瘤坏死因子-α(TNF-α)表达水平。结果 在细胞模型中,与空白对照组和siRNA-NC组相比,SIRT5-siRNA-2组的PKM2表达水平明显降低,差异有统计学意义。CSE干预后M1型促炎巨噬细胞表达增高,M2型抑炎巨噬细胞减少。M1型巨噬细胞随着SIRT5沉默而减少,过表达PKM2后又增多,差异有统计学意义(P<0.01)。与空白对照组相比,M2型巨噬细胞则在炎症模型中均降低,差异有统计学意义(P<0.05)。ELISA结果显示,与空白对照组相比,CSE干预组促炎因子IL-6、IL-12、TNF-α表达增高,抑炎因子IL-10表达降低,差异有统计学意义(P<0.01)。与CSE干预组相比,SIRT5-siRNA-2组下调了促炎因子表达同时也上调了抑炎因子水平,差异具有统计学意义(P<0.01)。SIRT5-siRNA-2+OE-PKM2组较SIRT5-siRNA-2组相比,又上调了IL-6、IL-12、TNF-α,同时IL-10的表达也增高,差异有统计学意义(P<0.01)。结论 SIRT5介导的PKM2通过降低IL-6、IL-12、TNF-α表达,促进IL-10表达,从而减轻香烟烟雾提取物诱导的巨噬细胞极化产生的炎症反应。 展开更多
关键词 慢性阻塞性肺疾病 SIRT5 PKM2 巨噬细胞 炎症
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基于多向扫描策略的嵌套命名实体识别模型
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作者 汪梦成 郝晓丽 雷鸣 《计算机工程与设计》 北大核心 2026年第2期503-510,共8页
为解决现有基于跨度的方法捕捉跨度间逻辑顺序和上下文信息不全面的问题,建立了一种基于多向扫描策略的嵌套命名实体识别模型。该模型通过多向扫描策略沿不同方向全面捕捉具有顺序关系的跨度特征,以便更加精确地表征跨度之间的内在联系... 为解决现有基于跨度的方法捕捉跨度间逻辑顺序和上下文信息不全面的问题,建立了一种基于多向扫描策略的嵌套命名实体识别模型。该模型通过多向扫描策略沿不同方向全面捕捉具有顺序关系的跨度特征,以便更加精确地表征跨度之间的内在联系。同时,该模型还引入了序列特征提取模块,用于捕捉距离当前跨度较远的其它跨度特征,进一步丰富了当前跨度的上下文信息。实验结果显示,相较于经典模型,该模型在特征提取方面有较大的提升。 展开更多
关键词 深度学习 自然语言处理 嵌套实体 信息抽取 实体多分类 实体词识别 预训练语言模型
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基于信息量模型的镇安县地质灾害易发性评价
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作者 王晓东 何新宁 +1 位作者 王鹏 董阳 《陕西水利》 2026年第3期101-103,114,共4页
以镇安县1∶5万地质灾害风险调查评价为基础,结合镇安县地质灾害发育特征,选取坡度、坡高、坡向、地层岩性、地质构造、河流水系和人类工程活动这七个孕灾地质条件因素,运用信息量模型对区内地质灾害易发性展开评价。更加科学精准划分... 以镇安县1∶5万地质灾害风险调查评价为基础,结合镇安县地质灾害发育特征,选取坡度、坡高、坡向、地层岩性、地质构造、河流水系和人类工程活动这七个孕灾地质条件因素,运用信息量模型对区内地质灾害易发性展开评价。更加科学精准划分镇安县地质灾害易发分区,减轻基层地质灾害防控难度,结果可为区内地质灾害风险评价、国土空间规划以及气象地质灾害预警预报提供基础支撑。 展开更多
关键词 地质灾害 易发性评价 信息量法
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任务类型对飞行员手册信息搜索行为的影响研究
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作者 谭维 李会聪 +3 位作者 王文青 孙源 温立宸 严鹏 《综合运输》 2026年第2期65-75,共11页
为提升航空运输安全与效率,本研究通过信息搜索实验研究飞行员在不同任务类型下搜索手册的行为。基于人机交互特性,将任务划分为查询型和研究型,通过实际运输场景(非正常、特殊),记录不同级别的飞行员所关注的手册模块,结合问卷数据与Ap... 为提升航空运输安全与效率,本研究通过信息搜索实验研究飞行员在不同任务类型下搜索手册的行为。基于人机交互特性,将任务划分为查询型和研究型,通过实际运输场景(非正常、特殊),记录不同级别的飞行员所关注的手册模块,结合问卷数据与Apriori关联规则算法,挖掘任务类型与手册及手册搜索行为之间的联系。关联规则结果表明:查询型任务会高频搜索操作程序,研究型任务会高频搜索系统理论,特殊场景下任务类型在搜索系统理论和操作程序中具有显著差异。实验结果表明:查询型任务的任务完成时间、高频词条个数、查询重构次数、浏览页面数量显著低于研究型任务(p<0.05),查询型任务时间紧迫但搜索绩效更高。本研究为航空运输中人机交互优化提供了手册设计依据,对飞行员在具体场景准确搜索手册内容提供了参考。 展开更多
关键词 信息搜索 飞行手册 任务类型 关联规则
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连接软管管径对小型分置式压缩制冷循环系统制冷性能的影响
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作者 胡仁东 张明 +4 位作者 刘浩 代明昊 程翱翔 丁东旭 吕祺 《暖通空调》 2026年第2期77-81,8,共6页
在实际应用场景中,鉴于安装空间狭窄、设备布局紧凑等现实条件,小型压缩制冷循环系统需要按零部件的功能进行分置安装。本文开展了不同管径连接软管的流动阻力试验研究,分析了不同压缩机转速和制冷剂充注量下不同管径连接软管对系统制... 在实际应用场景中,鉴于安装空间狭窄、设备布局紧凑等现实条件,小型压缩制冷循环系统需要按零部件的功能进行分置安装。本文开展了不同管径连接软管的流动阻力试验研究,分析了不同压缩机转速和制冷剂充注量下不同管径连接软管对系统制冷量和COP的影响。结果显示:连接软管管径≥6 mm时,在相同充注量下,系统制冷量和COP与光滑铜管系统基本持平或更高,可以替代光滑铜管,实现快速连接并解决安装空间受限、焊接操作不便的问题。 展开更多
关键词 分置式 压缩制冷 连接软管 管径 制冷性能 流动阻力 转速 充注量
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Lie symmetry and Hojman conserved quantity of a Nielsen equation in a dynamical system of relative motion with Chetaev-type nonholonomic constraint 被引量:2
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作者 王肖肖 孙现亭 +2 位作者 张美玲 解银丽 贾利群 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第12期259-263,共5页
The Lie symmetry and Hojman conserved quantity of Nielsen equations in a dynamical system of relative motion with nonholonomic constraint of the Chetaev type are studied. The differential equations of motion of the Ni... The Lie symmetry and Hojman conserved quantity of Nielsen equations in a dynamical system of relative motion with nonholonomic constraint of the Chetaev type are studied. The differential equations of motion of the Nielsen equation for the system, the definition and the criterion of Lie symmetry, and the expression of the Hojman conserved quantity deduced directly from the Lie symmetry for the system are obtained. An example is given to illustrate the application of the results. 展开更多
关键词 nonholonomic constraint of Chetaev's type relative motion Nielsen equation Hojman conserved quantity
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A New Type of Conserved Quantity of Mei Symmetry for Lagrange Systems 被引量:1
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作者 DING Ning FANG Jian-Hui WANG Peng ZHANG Xiao-Ni 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第5X期799-800,共2页
A new type of conserved quantity, which is induced from the Mei symmetry of Lagrange systems, is studied. The conditions for that the new type of conserved quantity exists and the form of the new type of conserved qua... A new type of conserved quantity, which is induced from the Mei symmetry of Lagrange systems, is studied. The conditions for that the new type of conserved quantity exists and the form of the new type of conserved quantity are obtained. An illustrated example is given. The Noether conserved quantity induced from the Mei symmetry of Lagrange systems is a special case of the new type of conserved quantity given in this paper. 展开更多
关键词 Mei symmetry new type of conserved quantity Lagrange system
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Mei Symmetry and Mei Conserved Quantity for a Non-holonomic System of Non-Chetaev's Type with Unilateral Constraints in Nielsen Style 被引量:1
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作者 CUI Jin-Chao JIA Li-Qun ZHANG Yao-Yu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第7期7-11,共5页
Mei symmetry and Mei conserved quantity for a non-holonomic system of non-Chetaev's type with unilateralconstraints in the Nielsen style are studied.The differential equations of motion for the system above are es... Mei symmetry and Mei conserved quantity for a non-holonomic system of non-Chetaev's type with unilateralconstraints in the Nielsen style are studied.The differential equations of motion for the system above are established.The definition and the criteria of Mei symmetry,conditions,and expressions of Mei conserved quantity deduced directlyfrom the Mei symmetry are given.An example is given to illustrate the application of the results. 展开更多
关键词 Nielscn stylc unilatcral constraint non-holonomic system of non-Chctaev's type Mci conscrvcd quantity
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A Wipe Transition Detection Approach Using Macroblock Type Information for MPEG Videos 被引量:1
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作者 王建 周源华 周磊 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第3期351-355,共5页
A new wipe transition detection approach was proposed. By analyzing the spatial-temporal characteristics of an ideal wipe production model, the concept of wipe transition strip (TS) was introduced. The macroblock type... A new wipe transition detection approach was proposed. By analyzing the spatial-temporal characteristics of an ideal wipe production model, the concept of wipe transition strip (TS) was introduced. The macroblock type information of P-frames is used to extract TS regions. An improved TS region accumulation technique is performed for detecting and verifying wipe transitions. The experimental results indicate that the proposed approach is capable of detecting various wipe transitions quickly and accurately. 展开更多
关键词 MPEG videos wipe transition detection macroblock type information transition strip
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