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TRANSFORMATION OF EFFUSION AND FORMATION OF GRANULATION TISSUE IN PATHOLOGIC PROCESS OF OTITIS MEDIA WITH EFFUSION 被引量:1
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作者 韦俊荣 张青 张全安 《Journal of Pharmaceutical Analysis》 SCIE CAS 2003年第2期170-172,188,共4页
Objective To explore the diversity of stagnant effusions and the pathologic processes leading to granulation tissue formation in otitis media with effusion(OME). Methods Temporal bone slides from 306 ears with OME w... Objective To explore the diversity of stagnant effusions and the pathologic processes leading to granulation tissue formation in otitis media with effusion(OME). Methods Temporal bone slides from 306 ears with OME were studied histopathologically under the light microscope. Results Results of this study revealed a pathologic process in witch the type and the condition of stagnant effusion in the middle ear cleft was a variable in the dynamics of OME progression from an early stage to an advanced stage. The location of granulation tissue and retentive effusion were found to be closely related. Conclusion Early stage granulation tissue formation exhibited a pathologic process in which granulation tissue formation occurred only in areas where effusion had stagnated or was absorbed. The incidence of the retentive effusion and formation of granulation tissue was much higher and the pathologic changes most extensive in the area around the ossicular chain. 展开更多
关键词 transformATION formatION EFFUSION granulation tissue otitis media
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The Transformation of Calcium Phosphate Bioceramics in Vivo
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作者 戴红莲 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2003年第2期19-22,共4页
To study the transformation process of calcium phosphate bioceramic in vivo,biodegradable porous β-tricalcium phosphate ceramics (β-TCP) were used in this experiment. The materials (5×8mm) were implanted in the... To study the transformation process of calcium phosphate bioceramic in vivo,biodegradable porous β-tricalcium phosphate ceramics (β-TCP) were used in this experiment. The materials (5×8mm) were implanted in the tibia of rabbits. The β-TCP ceramics with bone tissue were retrieved and treated for histology, and then observed by using a scanning electron microscope (SEM) and an electron probe X-ray microanalyzer (EMPA) every month. The results show that β-TCP ceramics bond to bone directly,new bones are forming and maturing with materials continuous degrading,and the materials are nearly replaced by the formed bone finally.Parts of the materials were degraded,absorpted and recrystallized,the others dispersped on the cancellous bone and the Haversian lamella with an irregular arrangement incorporating in bone formation directly by remodeling structure. 展开更多
关键词 calcium phosphate ceramics transformATION DEGRADATION incorporating in bone formation
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Discussion on the Application of Warm Yang to Promote Qi Transformation in Acne Mastitis from“Yang Promotes Qi Transformation and Yin Promotes Forming”
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作者 Yupei Chen Zhenlin Chen Pu Zhang 《Journal of Clinical and Nursing Research》 2021年第6期155-158,共4页
“Yang promotes Qi transformation and Yin promotes forming”maintains the normal progress of human life activities,which is an important embodiment of human vitality.The dysfunction of“Yang promotes Qi transformation... “Yang promotes Qi transformation and Yin promotes forming”maintains the normal progress of human life activities,which is an important embodiment of human vitality.The dysfunction of“Yang promotes Qi transformation and Yin promotes forming”leads to the coagulation of pathological products such as phlegm and blood stasis in the breast meridian,resulting in the occurrence of acne mastitis.In clinical treatment,we should take“warm Yang to promote Qi transformation”as the treatment principle,and add or subtract according to the specific situation. 展开更多
关键词 Yang promotes Qi transformation and Yin promotes formation Warm Yang to promote Qi transformation Acne mastitis
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Inverse Transformation of Elliptical Relative State Transition Matrix 被引量:1
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作者 Jianfeng Yin Yinrui Rao Chao Han 《International Journal of Astronomy and Astrophysics》 2014年第3期419-428,共10页
A new set of relative orbit elements (ROEs) is used to derive a new elliptical formation flying model in previous work. In-plane and out-of-plane relative motions can be completely decoupled, which benefits elliptical... A new set of relative orbit elements (ROEs) is used to derive a new elliptical formation flying model in previous work. In-plane and out-of-plane relative motions can be completely decoupled, which benefits elliptical formation design. In order to study the elliptical control strategy and perturbation effects, it is necessary to derive the inverse transformation of the relative state transition matrix based on relative orbit elements. Poisson bracket theory is used to obtain the linear transformations between the two representations: the relative orbit elements and the geocentric orbital frame. In this paper, the details of these transformations are presented. 展开更多
关键词 RELATIVE ORBIT Elements ELLIPTICAL formation FLYING RELATIVE State Transition Matrix Inverse transformation POISSON BRACKET
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THEORETICAL PREDICTION OF THE KINETICS CURVES OFPEARLITIC TRANSFORMATION IN HYPO-PROEUTECTOID STRUCTURAL STEELS 被引量:4
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作者 Z.G.Li H.B.Chang +2 位作者 T.Y.Hsu Z.Y.Xu X.Y.Ruan 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1998年第3期215-224,共10页
Supposing carbon contents of ferrite phases in pearlite precipitating from austenite in multicomponent steel at temperature T and in Fe-C ystem at T' are the same the pearlite formation temperature diference, can ... Supposing carbon contents of ferrite phases in pearlite precipitating from austenite in multicomponent steel at temperature T and in Fe-C ystem at T' are the same the pearlite formation temperature diference, can be calculated from the FeX phase diagrams and the equilibrium temperature Al. Using Tp and Fe-C binary thermodynamic model, the driving forces for phase transformation from austenite to pearlite in multicomponent steels have been successfully calculated. Through the combination of simplified Zener and Hillert's model for pearlite growth with Johnson-Mehl equation, using data from known TTT diagrams, the interfacial energy parameter and activation energy for pearlite formation can be determined and expressed as functions of chemical composition in steels by regression analysis. The calculated starting curves of pearlitic transformation in some commercial steels agree well with the experimental data. 展开更多
关键词 pearlite formation temperature difference interfacial energy parameter activation enerpy for pearlite transformation Johnson-Mehl equation
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在VC++6.0下读取408UL的SEGD format4.0 被引量:2
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作者 吴莉莉 刘益成 《石油仪器》 2003年第2期37-39,62,共3页
40 8UL地震数据采集系统是一种新颖且功能强大的采集系统 ,它存储数据所采用的格式为SEGDformat4 .0。很多情况下 ,需要在PC机上对这种格式存放的数据进行处理和检测等 ,而PC机上常选用在VC 6 .0环境下对数据进行处理。文章讨论了在VC ... 40 8UL地震数据采集系统是一种新颖且功能强大的采集系统 ,它存储数据所采用的格式为SEGDformat4 .0。很多情况下 ,需要在PC机上对这种格式存放的数据进行处理和检测等 ,而PC机上常选用在VC 6 .0环境下对数据进行处理。文章讨论了在VC 6 .0环境下如何读取文件格式 。 展开更多
关键词 VC++6.0 408UL SEGDformat4.0 格式转化 地震数据采集系统
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Developing a Geological Management Information System: National Important Mining Zone Database 被引量:1
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作者 左仁广 汪新庆 夏庆霖 《Journal of China University of Geosciences》 SCIE CSCD 2006年第1期79-83,94,共6页
Geo-data is a foundation for the prediction and assessment of ore resources, so managing and making full use of those data, including geography database, geology database, mineral deposits database, aeromagnetics data... Geo-data is a foundation for the prediction and assessment of ore resources, so managing and making full use of those data, including geography database, geology database, mineral deposits database, aeromagnetics database, gravity database, geochemistry database and remote sensing database, is very significant. We developed national important mining zone database (NIMZDB) to manage 14 national important mining zone databases to support a new round prediction of ore deposit. We found that attention should be paid to the following issues: ① data accuracy: integrity, logic consistency, attribute, spatial and time accuracy; ② management of both attribute and spatial data in the same system;③ transforming data between MapGIS and ArcGIS; ④ data sharing and security; ⑤ data searches that can query both attribute and spatial data. Accuracy of input data is guaranteed and the search, analysis and translation of data between MapGIS and ArcGIS has been made convenient via the development of a checking data module and a managing data module based on MapGIS and ArcGIS. Using AreSDE, we based data sharing on a client/server system, and attribute and spatial data are also managed in the same system. 展开更多
关键词 geological management information system checking data ARCSDE transforming data format data sharing data security
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Cooperative coalition for formation flight scheduling based on incomplete information 被引量:9
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作者 Meng Linghang Xu Xiaohao Zhao Yifei 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2015年第6期1747-1757,共11页
This study analyzes the cooperative coalition problem for formation scheduling based on incomplete information. A multi-agent cooperative coalition framework is developed to optimize the formation scheduling problem i... This study analyzes the cooperative coalition problem for formation scheduling based on incomplete information. A multi-agent cooperative coalition framework is developed to optimize the formation scheduling problem in a decentralized manner. The social class differentiation mech- anism and role-assuming mechanism are incorporated into the framework, which, in turn, ensures that the multi-agent system (MAS) evolves in the optimal direction. Moreover, a further differen- tiation pressure can be achieved to help MAS escape from local optima. A Bayesian coalition nego- tiation algorithm is constructed, within which the Harsanyi transformation is introduced to transform the coalition problem based on incomplete information to the Bayesian-equivalent coali- tion problem based on imperfect information. The simulation results suggest that the distribution of agents' expectations of other agents' unknown information approximates to the true distribution after a finite set of generations. The comparisons indicate that the MAS cooperative coalition algo- rithm produces a significantly better utility and possesses a more effective capability of escaping from local optima than the proposal-engaged marriage algorithm and the Simulated Annealing algorithm. 展开更多
关键词 Coalition Commercial aviation formation flight Harsanyi transformation Incomplete information Multi agent systems (MAS) SCHEDULING
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Leader trajectory planning method considering constraints of formation controller
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作者 YAO Dongdong WANG Xiaofang +1 位作者 LIN Hai WANG Zhuping 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第5期1294-1308,共15页
To ensure safe flight of multiple fixed-wing unmanned aerial vehicles(UAVs)formation,considering trajectory planning and formation control together,a leader trajectory planning method based on the sparse A*algorithm i... To ensure safe flight of multiple fixed-wing unmanned aerial vehicles(UAVs)formation,considering trajectory planning and formation control together,a leader trajectory planning method based on the sparse A*algorithm is introduced.Firstly,a formation controller based on prescribed performance theory is designed to control the transient and steady formation configuration,as well as the formation forming time,which not only can form the designated formation configuration but also can guarantee collision avoidance and terrain avoidance theoretically.Next,considering the constraints caused by formation controller on trajectory planning such as the safe distance,turn angle and step length,as well as the constraint of formation shape,a leader trajectory planning method based on sparse A^(*)algorithm is proposed.Simulation results show that the UAV formation can arrive at the destination safely with a short trajectory no matter keeping the formation or encountering formation transformation. 展开更多
关键词 trajectory planning formation control prescribed performance controller multiple constraints formation shape formation transformation
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EFFECTS OF TEST TEMPERATURE AND STRAIN RATE ON THE MECHANICAL PROPERTIES IN AN INTERCRITICALLYHEAT-TREATED BAINITE-TRANSFORMED STEEL 被引量:2
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作者 Z.Li D.Wu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2004年第6期840-848,共9页
Larger amount of austenite could be retained in an intercritically heat-treated bainite- transformed steel. The elongation and the strength-ductility balance of the steel could be enhanced considerably due to strain-i... Larger amount of austenite could be retained in an intercritically heat-treated bainite- transformed steel. The elongation and the strength-ductility balance of the steel could be enhanced considerably due to strain-induced martensite transformation and transformation- induced plasticity (TRIP) of retained austenite. The effects of test temperature and strain rate on the mechanical properties and strain induced transformation behavior of retained austenite in the steel were investigated. Total elongation and strength-ductility balance of the specimen reached maximum when it strained at a strain rate of 2.8×10-4s-1 and at 350℃. The relation between test temperature and tensile properties showed the same tendency at three kinds of strain rates. Flow stress increased considerably with decreasing the strain rate. 展开更多
关键词 strain rate mechanical property strain-induced transformation trans- formation-induced plasticity (TRIP)
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P144 Increases Adipose Tissue Volume by Inhibiting TGF-<i>β</i>1-Mediated Fibrous Capsule Formation in a Tissue Engineering Chamber
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作者 Yaodong Yuan Jianhua Gao +3 位作者 Zi Jing Yan Shi Feng Lu Zhangbo Chen 《Journal of Biosciences and Medicines》 2021年第12期98-109,共12页
Tissue engineering chambers (TECs) represent a new and attractive in vivo tissue engineering model that can successfully generate mature adipose tissue. However, the newly formed adipose tissue is not able to fill the... Tissue engineering chambers (TECs) represent a new and attractive in vivo tissue engineering model that can successfully generate mature adipose tissue. However, the newly formed adipose tissue is not able to fill the volume of the chamber as expected. To investigate whether the capsule surrounding the newly formed adipose tissue limits the adipose tissue volume in the chamber, we detected fibrotic parameters two months after these chambers were implanted into rats. The results showed that the newly formed adipose tissue was surrounded by a thick layer of capsule, and the protein levels of transforming growth factor-<em>β</em>1 (TGF-<em>β</em>1), phosphorylated Smad2 (p-Smad2), connective tissue growth factor (CTGF), collagen type I (COL-I) and α-smooth muscle actin (<em>α</em>-SMA) in the capsule were increased. The levels of these proteins decreased following systemic administration of P144 (a peptide inhibitor of TGF-<em>β</em>1). Furthermore, the capsule thickness was significantly reduced, and the adipose tissue volume was markedly greater when using P144. These findings indicate that capsule formation, which is mediated through a TGF-<em>β</em>1 signaling pathway, restricted the volume of the engineered adipose tissue that was formed. This study may provide a new approach to regenerate amounts of adipose tissue for the reconstruction of large soft tissue defects. 展开更多
关键词 Adipose Tissue Tissue Engineering Chamber Capsule formation transforming Growth Factor-β1 P144
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Simultaneous ISAR imaging of group targets flying in formation
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作者 Chen Jie Xiao Huaitie +1 位作者 Song Zhiyong Fan Hongqi 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2014年第6期1554-1561,共8页
This paper proposes a novel inverse synthetic aperture radar(ISAR) imaging method based on second-order keystone transform(KT) and Sandglass transform for group targets flying in a formation with constant accelera... This paper proposes a novel inverse synthetic aperture radar(ISAR) imaging method based on second-order keystone transform(KT) and Sandglass transform for group targets flying in a formation with constant accelerated rectilinear motion in the same radar beam. First, range curvature and range walk of each sub-target among group targets are corrected by the second-order KT combined with the quadratic phase term compensation. After range alignment, the signals in each range frequency cell can be modelled as multiple chirp signals and then the Sandglass transform is utilized to cross-range imaging, which transforms the time–frequency distribution of the signals in each range frequency cell into beelines parallel to the slow time axis simultaneously. Finally, cross-range profiles of group targets in each range frequency cell are obtained via a projection of the perk of every scatterer in the two-dimensional accumulation plane onto the frequency axis. The advantage of the proposed method is that it can align range profiles of each sub-target simultaneously and image cross-range profiles directly without separating the returned signals, which simplifies the operation procedure. Simulation results are used to demonstrate the effectiveness of the proposed method. 展开更多
关键词 formation flying Group targets Inverse synthetic aperture radar Keystone transform Radar imaging Sandglass transform
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Basic Elements Knowledge Acquisition Study in the Chinese Character Intelligent Formation System
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作者 Mingyou LIU Chengsen DUAN Youguo PI 《Journal of Software Engineering and Applications》 2009年第5期316-322,共7页
In the Chinese character intelligent formation system without Chinese character library, it is possible that the same basic element in different Chinese characters is different in position, size and shape. The geometr... In the Chinese character intelligent formation system without Chinese character library, it is possible that the same basic element in different Chinese characters is different in position, size and shape. The geometry transformation from basic elements to the components of Chinese characters can be realized by affine transformation, the transformation knowledge acquisition is the premise of Chinese character intelligent formation. A novel algorithm is proposed to ac-quire the affine transformation knowledge of basic elements automatically in this paper. The interested region of Chi-nese character image is determined by the structure of the Chinese character. Scale invariant and location invariant of basic element and Chinese character image are extracted with SIFT features, the matching points of the two images are determined according to the principle of Minimum Euclidean distance of eigenvectors. Using corner points as identifi-cation features, calculating the one-way Hausdorff distance between corner points as the similarity measurement from the affine image to the Chinese character sub-image, affine coefficients are determined by optimal similarity. 70244 Chinese characters in National Standards GB18030-2005 character set are taken as the experimental object, all the characters are performed and the experimental courses and results are presented in this paper. 展开更多
关键词 Chinese CHARACTER INTELLIGENT formatION KNOWLEDGE Acquisition AFFINE transformation HAUSDORFF Distance
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航天器编队轨迹跟踪Port-Hamiltonian控制方法
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作者 刘俊 包素艳 +1 位作者 陈琪锋 郝文康 《国防科技大学学报》 北大核心 2025年第3期64-72,共9页
针对航天器编队相对运动构型时变轨迹跟踪控制问题,基于端口哈密顿(port-Hamiltonian,PH)模型和广义正则变换,采用互联阻尼分配无源控制(interconnection and damping assignment passivity-based control,IDA-PBC)算法设计了一种分布... 针对航天器编队相对运动构型时变轨迹跟踪控制问题,基于端口哈密顿(port-Hamiltonian,PH)模型和广义正则变换,采用互联阻尼分配无源控制(interconnection and damping assignment passivity-based control,IDA-PBC)算法设计了一种分布式协调控制律。通过对航天器编队线性动力学的PH建模和广义正则变换,得到轨迹跟踪误差PH系统。在拓扑结构连通且固定的假设下,利用相对运动误差PH系统模型,基于IDA-PBC算法推导出了考虑邻居航天器间相对误差的轨迹跟踪分布式协调控制律。数值仿真验证了控制律的有效性,结果表明,利用PH控制方法可以完成航天器编队轨迹跟踪控制,为航天器编队分布式协调控制提供了一种新的有效方法。 展开更多
关键词 航天器编队 广义正则变换 轨迹跟踪 IDA-PBC port-Hamiltonian
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数字化赋能就业高质量发展的内在逻辑、现实困境与纾解路径 被引量:8
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作者 杨仲迎 《重庆社会科学》 北大核心 2025年第1期66-81,共16页
数字化赋能就业高质量发展,不仅是新质生产力发展态势下的必然选择,还是保障社会和谐稳定发展的重要举措,也体现出基于共同发展需要驱动而双向奔赴的内在逻辑关系,已成为新时代经济高质量发展的题中应有之义和当务之需。但快速和不均衡... 数字化赋能就业高质量发展,不仅是新质生产力发展态势下的必然选择,还是保障社会和谐稳定发展的重要举措,也体现出基于共同发展需要驱动而双向奔赴的内在逻辑关系,已成为新时代经济高质量发展的题中应有之义和当务之需。但快速和不均衡数字化赋能授权造成了技术性失业、收入波动、岗位错配等就业风险,同时亦面临着就业观念转变难、经济发展格局调整难、结构性就业矛盾纾解难、供需匹配质效提增难等就业高质量发展的现实困境。故以马克思主义科学技术观为指导,按照问题导向,主动应变数字化赋能策略和方式,着力从数字化就业新理念贯彻、服务型就业新生态创建、高质量充分就业新结构优化、合理性数字就业新模式构建等几个途径推进就业高质量发展难题的有效纾解。 展开更多
关键词 数字化转型 赋能 高质量充分就业 新业态
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不同坐标系转换方式下舰艇编队协同定位精度分析
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作者 王苏 黄鸿殿 +1 位作者 周红进 赵健文 《现代电子技术》 北大核心 2025年第21期120-126,共7页
针对水面舰艇编队协同定位系统欧氏距离量测模型建立过程中的坐标系转换问题,以舰艇经纬度与速度为系统状态,在此基础上分析不同坐标系转换方式对系统定位精度的影响。首先,建立舰艇编队协同定位系统状态模型,并针对地心地固坐标系、基... 针对水面舰艇编队协同定位系统欧氏距离量测模型建立过程中的坐标系转换问题,以舰艇经纬度与速度为系统状态,在此基础上分析不同坐标系转换方式对系统定位精度的影响。首先,建立舰艇编队协同定位系统状态模型,并针对地心地固坐标系、基于弧度近似的平面直角坐标系和基于墨卡托投影的坐标系与经纬度坐标的转换方式,分别推导不同坐标系转换方式下的系统量测方程;然后,根据不同坐标系转换原理推导相应的误差传递方程,并通过数值分析方法分析不同坐标系转换方式下舰艇间距离解算误差,以及舰艇间测距传递误差所导致的协同定位误差。通过仿真实验可以看出,基于地心地固坐标系进行经纬度坐标转换的舰艇编队协同定位精度最高,与基于墨卡托投影、弧度近似坐标系转换方式相比,系统定位精度分别提高1.78%和4.32%,可知基于地心地固坐标系进行经纬度转换的方法可应用于精密定位场景中。 展开更多
关键词 协同定位 坐标系转换 地心地固坐标系 墨卡托投影 舰艇编队 惯性导航
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工业场景下的数据价值形成机理与评估方法研究
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作者 刘小茵 郭伟龙 《数字化转型》 2025年第5期21-28,共8页
聚焦工业数字化转型背景,深入剖析工业场景下的数据价值内涵、形成机理与评估方法,揭示了数据在工业流程各环节创造价值的路径,构建了工业数据价值形成理论模型,分析了工业场景下的数据资产不同评估方法的利弊,并对工业数据价值评估发... 聚焦工业数字化转型背景,深入剖析工业场景下的数据价值内涵、形成机理与评估方法,揭示了数据在工业流程各环节创造价值的路径,构建了工业数据价值形成理论模型,分析了工业场景下的数据资产不同评估方法的利弊,并对工业数据价值评估发展提出了展望。研究成果可以帮助工业企业深入理解数据价值潜力、挖掘工业数据价值,为制定工业数据全生命周期数据价值应用策略提供支撑。 展开更多
关键词 工业数字化转型 数据价值 形成机理 评估方法
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Composition and distribution of NSO compounds in two different shales at the early maturity stage characterized by negative ion electrospray ionization coupled with Fourier transform ion cyclotron resonance mass spectrometry
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作者 Chang-Wei Ke Yao-Hui Xu +1 位作者 Xiang-Chun Chang Wei-Bin Liu 《Petroleum Science》 SCIE CAS CSCD 2018年第2期289-296,共8页
Gas chromatography/mass spectrometry (GC/MS) can only analyze volatile molecular compounds, and it has limitations when applied to determine the complex components of crude oils and hydrocarbon source rocks. Based o... Gas chromatography/mass spectrometry (GC/MS) can only analyze volatile molecular compounds, and it has limitations when applied to determine the complex components of crude oils and hydrocarbon source rocks. Based on Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) and GC/MS analyses, the molecular compositions of NSO compounds in extracts from the Permian Dalong Formation, Sichuan Basin and the Permian Lucaogou Formation, Junggar Basin in China were compared. Analyses of types of heteroatoms present (S~, $2, $3, OS, OS2, 02S, NS, and NOS compounds) suggest that marine shales from the Dalong Formation are mainly composed of carboxylic acids (02 com- pounds) with a high abundance of fatty acids, indicating a marine phytoplankton organic source. However, lacustrine shales from the Lucaogou Formation are dominated by pyrrolic compounds (N1 compounds) with abundant dibenzocar- bazole. It suggests that the organic source materials may be derived from lower aquatic organisms and lacustrine algae. Overall, FT-ICR-MS has potential for applications in analyses and determination of depositional environments and organic sources in petroleum geology. 展开更多
关键词 Fourier transform ion cyclotron resonance mass spectrometry Dalong formation Lucaogou formation NSO compounds Sedimentary environment
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基于优化人工势场法的智能车辆编队避障策略研究
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作者 孙羽 曹曼曼 +1 位作者 王强 孙博华 《汽车技术》 北大核心 2025年第7期31-39,共9页
为克服动态、不确定的复杂行车环境带来的车辆编队碰撞与稳定性问题,提高行车安全性,提出了一种基于优化人工势场法的智能车辆编队避障策略。设计了智能车辆编队避障策略框架,建立了基于经典人工势场法的车辆编队控制器,以及具备莱维飞... 为克服动态、不确定的复杂行车环境带来的车辆编队碰撞与稳定性问题,提高行车安全性,提出了一种基于优化人工势场法的智能车辆编队避障策略。设计了智能车辆编队避障策略框架,建立了基于经典人工势场法的车辆编队控制器,以及具备莱维飞行随机搜索特性的车辆编队搜索逻辑,以克服人工势场法中引力与斥力增量系数设置的局限性,进而增强车辆编队对复杂行车环境的适应能力。采用联合仿真试验平台对所提出的算法进行了验证,结果表明,基于优化人工势场法的智能车辆编队避障能够更加快速地适应较为复杂的行车环境,并具备更短的编队避障时间。 展开更多
关键词 智能车辆 编队控制 人工势场 莱维飞行 队形异构变换
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Multiple Targets Recognition for Highly-Compressed Color Images in a Joint Transform Correlator
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作者 Abdallah K. Cherri Alshahd S. Nazar 《Optics and Photonics Journal》 2022年第5期107-127,共21页
In this paper, we are proposing a compression-based multiple color target detection for practical near real-time optical pattern recognition applications. By reducing the size of the color images to its utmost compres... In this paper, we are proposing a compression-based multiple color target detection for practical near real-time optical pattern recognition applications. By reducing the size of the color images to its utmost compression, the speed and the storage of the system are greatly increased. We have used the powerful Fringe-adjusted joint transform correlation technique to successfully detect compression-based multiple targets in colored images. The colored image is decomposed into three fundamental color components images (Red, Green, Blue) and they are separately processed by three-channel correlators. The outputs of the three channels are then combined into a single correlation output. To eliminate the false alarms and zero-order terms due to multiple desired and undesired targets in a scene, we have used the reference shifted phase-encoded and the reference phase-encoded techniques. The performance of the proposed compression-based technique is assessed through many computer simulation tests for images polluted by strong additive Gaussian and Salt & Pepper noises as well as reference occluded images. The robustness of the scheme is demonstrated for severely compressed images (up to 94% ratio), strong noise densities (up to 0.5), and large reference occlusion images (up to 75%). 展开更多
关键词 Image Compression JPEG Image format Multiple Targets Detection Fringe-Adjusted Joint transform Correlation Random-Phase Mask
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