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Research on the Upper Limit of Accuracy for Predicting Theoretical Tandem Mass Spectrometry
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作者 Changjiu He Xiaoyu Wang +1 位作者 Mingming Lyu Xinye Bian 《Journal of Computer and Communications》 2024年第3期184-195,共12页
In recent years, numerous theoretical tandem mass spectrometry prediction methods have been proposed, yet a systematic study and evaluation of their theoretical accuracy limits have not been conducted. If the accuracy... In recent years, numerous theoretical tandem mass spectrometry prediction methods have been proposed, yet a systematic study and evaluation of their theoretical accuracy limits have not been conducted. If the accuracy of current methods approaches this limit, further exploration of new prediction techniques may become redundant. Conversely, a need for more precise prediction methods or models may be indicated. In this study, we have experimentally analyzed the limits of accuracy at different numbers of ions and parameters using repeated spectral pairs and integrating various similarity metrics. Results show significant achievements in accuracy for backbone ion methods with room for improvement. In contrast, full-spectrum prediction methods exhibit greater potential relative to the theoretical accuracy limit. Additionally, findings highlight the significant impact of normalized collision energy and instrument type on prediction accuracy, underscoring the importance of considering these factors in future theoretical tandem mass spectrometry predictions. 展开更多
关键词 Tandem Mass Spectrometry Spectral prediction theoretical Limit
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Theoretical prediction of forming limit diagram of AZ31 magnesium alloy sheet at warm temperatures 被引量:3
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作者 曹晓卿 徐平平 +1 位作者 樊奇 王文先 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第9期2426-2432,共7页
A theoretical prediction on forming limit diagram(FLD) of AZ31 magnesium alloy sheet was developed at warm temperatures based on the M-K theory. Two different yield criteria of von Mises and Hill'48 were applied in... A theoretical prediction on forming limit diagram(FLD) of AZ31 magnesium alloy sheet was developed at warm temperatures based on the M-K theory. Two different yield criteria of von Mises and Hill'48 were applied in this model. Mechanical properties of AZ31 magnesium alloy used in the prediction were obtained by uniaxial tensile tests and the Fields-Backofen equation was incorporated in the analysis. In addition, experimental FLDs of AZ31 were acquired by conducting rigid die swell test at different temperatures to verify the prediction. It is demonstrated from a comparison between the predicted and the experimental FLDs at 473 K and 523 K that the predicted results are influenced by the type of yield criterion used in the calculation, especially at lower temperatures. Furthermore, a better agreement between the predicted results and experimental data for AZ31 magnesium alloy sheet at warm temperatures was obtained when Hill'48 yield criterion was applied. 展开更多
关键词 magnesium alloy forming limit diagram theoretical prediction yield criterion sheet warm forming
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Prediction of the amount of urban waste solids by applying a gray theoretical model 被引量:11
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作者 LI Xiao ming, ZENG Guang ming, WANG Ming, LIU Jin jin (Department of Environmental Science and Technology, Hunan University, Changsha 410082, China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第1期43-46,共4页
Urban waste solids are now becoming one of the most crucial environmental problems. There are several different kinds of technologies normally used for waste solids disposal, among which landfill is more favorable in ... Urban waste solids are now becoming one of the most crucial environmental problems. There are several different kinds of technologies normally used for waste solids disposal, among which landfill is more favorable in China than others, especially for urban waste solids. Most of the design works up to now are based on a roughly estimation of the amount of urban waste solids without any theoretical support, which lead to a series problems. To meet the basic information requirements for the design work, the amount of the urban waste solids was predicted in this research by applying the gray theoretical model GM (1,1) through non linear differential equation simulation. The model parameters were estimated with the least square method (LSM) by running a certain MATALAB program, and the hypothesis test results show that the residual between the prediction value and the actual value approximately comply with the normal distribution N (0,0 21 2), and the probability of the residual within the range (-0 17, 0 19) is more than 95%, which indicate obviously that the model can be well used for the prediction of the amount of waste solids and those had been already testified by the latest two years data about the urban waste solids from Loudi City of China. With this model, the predicted amount of the waste solids produced in Loudi City in the next 30 years is 8049000 ton in total. 展开更多
关键词 gray theoretical model predictION waste solids
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Theoretical prediction on corrugated sandwich panels under bending loads 被引量:3
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作者 Chengfu Shu Shujuan Hou 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2018年第5期925-935,共11页
In this paper,an aluminum corrugated sandwich panel with triangular core under bending loads was investigated.Firstly,the equivalent material parameters of the triangular corrugated core layer,which could be considere... In this paper,an aluminum corrugated sandwich panel with triangular core under bending loads was investigated.Firstly,the equivalent material parameters of the triangular corrugated core layer,which could be considered as an orthotropic panel,were obtained by using Castigliano's theorem and equivalent homogeneous model.Secondly,contributions of the corrugated core layer and two face panels were both considered to compute the equivalent material parameters of the whole structure through the classical lamination theory,and these equivalent material parameters were compared with finite element analysis solutions.Then,based on the Mindlin orthotropic plate theory,this study obtain the closed-form solutions of the displacement for a corrugated sandwich panel under bending loads in specified boundary conditions,and parameters study and comparison by the finite element method were executed simultaneously. 展开更多
关键词 Corrugated SANDWICH PANEL EQUIVALENT material PARAMETER theoretICAL prediction BENDING loads
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Theoretical Prediction of Gibbs Free Energies of Formation for Crystallineα-MOOH andα-M_2O_3 Based on a Linear Free-Energy Relationship 被引量:1
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作者 SUN Xiaoming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第3期656-660,共5页
In the present study,the modified Sverjensky-Molling equation,derived from a linear-free energy relationship,is used to predict the Gibbs free energies of formation of crystalline phases ofα-MOOH (with a goethite st... In the present study,the modified Sverjensky-Molling equation,derived from a linear-free energy relationship,is used to predict the Gibbs free energies of formation of crystalline phases ofα-MOOH (with a goethite structure)andα-M_2O_3(with a hematite structure)from the known thermodynamic properties of the corresponding aqueous trivalent cations(M^(3+)).The modified equation is expressed asΔG_(f,M_VX)~0=a_(M_VX)ΔG_(0,M^(3+))^(0)+b_(M_VX)+β_(M_VXγM^(3+)),where the coefficients a_(M_VX),b_(M_VX),andβ_(M_VX) characterize a particular structural family of M_VX(M is a trivalent cation[M^(3+)]and X represents the remainder of the composition of solid);γ^(3+)is the ionic radius of trivalent cations(M^(3+));ΔG_(f,M_VX)~0 is the standard Gibbs free energy of formation of M_vX;andΔG_(n,M^(3+))~0 is the non-solvation energy of trivalent cations(M^(3+)).By fitting the equation to the known experimental thermodynamic data,the coefficients for the goethite family(α-MOOH)are a_(M_VX)=0.8838,b_(M_VX)=-424.4431(kcal/mol),andβ_(M_VX)=115(kcal/ mol.(?)),while the coefficients for the hematite family(α-M_2O_3)are a_(M_VX)=1.7468,b_(M_VX)=-814.9573(kcal/ mol),andβ_(M_VX)=278(kcal/mol.(?)).The constrained relationship can be used to predict the standard Gibbs free energies of formation of crystalline phases and fictive phases(i.e.phases that are thermodynamically unstable and do not occur at standard conditions)within the isostructural families of goethite(α-MOOH)and hematite(α-M_2O_3)if the standard Gibbs free energies of formation of the trivalent cations are known. 展开更多
关键词 α-MOOH α-M_2O_3 Gibbs free energy theoretical prediction
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Theoretical Prediction of the Photovoltaic Properties of BFBPD-PC61 BM System as a Promising Organic Solar Cell 被引量:1
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作者 赵蔡斌 马剑琪 +3 位作者 葛红光 唐志华 靳玲侠 王文亮 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第1期15-26,共12页
In this work,the photovoltaic properties of BFBPD-PC61 BM system as a promising high-performance organic solar cell(OSC) were theoretically investigated by means of quantum chemistry and molecular dynamics calculati... In this work,the photovoltaic properties of BFBPD-PC61 BM system as a promising high-performance organic solar cell(OSC) were theoretically investigated by means of quantum chemistry and molecular dynamics calculations coupled with the incoherent charge-hopping model.Moreover,the hole carrier mobility of BFBPD thin-film was also estimated with the aid of an amorphous cell including 100 BFBPD molecules.Results revealed that the BFBPD-PC61 BM system possesses a middle-sized open-circuit voltage of 0.70 V,large short-circuit current density of 17.26 mA ·cm^-2,high fill factor of 0.846,and power conversion efficiency of 10%.With the Marcus model,in the BFBPD-PC61 BM interface,the exciton-dissociation rate,kdis,was predicted to be 2.684×10^13 s^-1,which is as 3-5 orders of magnitude large as the decay(radiative and non-radiative) one(10-8-10^10s^-1),indicating a high exciton-dissociation efficiency of 100% in the BFBPD-PC61 BM interface.Furthermore,by the molecular dynamics simulation,the hole mobility of BFBPD thin-film was predicted to be as high as 1.265 × 10^-2 cm-2·V^-1·s^-1,which can be attributed to its dense packing in solid state. 展开更多
关键词 photovoltaic performances theoretical prediction carrier mobility hopping mechanism
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Ab Initio Theoretical Prediction on Structures of Boron Cationic Cluster B_(17)^+
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作者 Xu-Guang HU Yu-Min CAI Qian-Shu LI(Institute of Theoretical Chemistry, National Key Laboratory of Theoretical and Computational Chemistry, Jilin University, Changchun 130023)(Department of Chemical Engineering, Xi an Petroleum Institute,Xi an, 710061)(Col 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第8期737-740,共4页
Four isomers of the three-dimensionally connected bare boron cationic cluster B were investigated by using ab initio molecular orbital theory at the HF/6-31G level. The results show that the D5h symmetric isomer of B ... Four isomers of the three-dimensionally connected bare boron cationic cluster B were investigated by using ab initio molecular orbital theory at the HF/6-31G level. The results show that the D5h symmetric isomer of B is a possible isomer candidate of its stable geometries with closed structure. 展开更多
关键词 Ab Initio theoretical prediction on Structures of Boron Cationic Cluster B
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基坑降水引发的沉降理论计算及预测研究 被引量:1
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作者 彭伟 《粉煤灰综合利用》 CAS 2024年第1期100-106,共7页
为有效掌握基坑沉降变形规律,以基坑所处地质条件为基础,先结合有效应力原理,利用分层综合法计算基坑降水引发的沉降理论值;其次,再以基坑施工过程中的现场沉降监测数据为基础,通过变形预测来佐证理论计算值的准确性。分析结果表明:在... 为有效掌握基坑沉降变形规律,以基坑所处地质条件为基础,先结合有效应力原理,利用分层综合法计算基坑降水引发的沉降理论值;其次,再以基坑施工过程中的现场沉降监测数据为基础,通过变形预测来佐证理论计算值的准确性。分析结果表明:在基坑沉降的理论计算结果中,沉降理论计算值均不同程度的小于沉降监测值,且随着与降水井中心距离的增加,沉降值具持续减小特征;在基坑沉降的预测研究结果中,所得预测结果的相对误差均值介于2.02%~2.09%,说明ILSO-RVM-CT在基坑沉降变形预测中具有较强的预测能力,且预测结果显示基坑沉降变形后续还会具小速率增加特征,说明基坑沉降变形趋于稳定。 展开更多
关键词 基坑 降水 沉降理论计算 变形预测
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负泊松比点阵结构填充薄壁管轴向压缩行为及吸能特性
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作者 李海玉 王雷 +2 位作者 王陶 王利 黄昭明 《材料科学与工艺》 CAS CSCD 北大核心 2024年第3期96-103,共8页
薄壁填充结构具有轻量化、高比吸能的优点,被广泛应用于航空航天、汽车、轨道交通等工程领域。负泊松比结构在受到冲击时力学性能会逐渐增强,因此本文基于双箭头型负泊松比点阵提出一种新型薄壁填充管吸能结构,通过准静态压缩实验和有... 薄壁填充结构具有轻量化、高比吸能的优点,被广泛应用于航空航天、汽车、轨道交通等工程领域。负泊松比结构在受到冲击时力学性能会逐渐增强,因此本文基于双箭头型负泊松比点阵提出一种新型薄壁填充管吸能结构,通过准静态压缩实验和有限元数值模拟方法研究了新型填充管在压缩载荷作用下的变形失效模式与力学响应。建立了平均碰撞力的理论预测模型,并通过有限元分析验证了模型可靠性,在此基础上研究了负泊松比点阵结构的细观设计参数对填充管抗压缩性能的影响规律。结果表明,填充管在压缩载荷作用下的失效模式为局部屈曲失效,相比于单一薄壁管与点阵结构,填充管具有更好的抗压缩性能;通过参数分析明确了通过增加胞元杆件壁厚和下支撑杆夹角,能显著提高填充管抗压缩性能,这将为后续负泊松比点阵填充结构的抗冲击优化设计提供重要参考。 展开更多
关键词 负泊松比 点阵结构 填充管 理论预测模型 细观设计参数
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攀西某强蚀变钒钛磁铁矿钛的赋存状态及理论指标预测
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作者 刘飞燕 徐力 +1 位作者 陈超 徐妍博 《有色金属(选矿部分)》 CAS 2024年第6期13-20,39,共9页
攀西四大矿区是我国战略资源铁、钛主产区,铁、钛均可综合利用,矿集区内铁主要从钛磁铁矿中回收,钛主要从钛铁矿中回收,从其他矿物中回收的类型鲜有报道。对攀西某地强蚀变矿石研究发现,矿石中铁含量低,主要赋存于绿泥石中,无利用价值;... 攀西四大矿区是我国战略资源铁、钛主产区,铁、钛均可综合利用,矿集区内铁主要从钛磁铁矿中回收,钛主要从钛铁矿中回收,从其他矿物中回收的类型鲜有报道。对攀西某地强蚀变矿石研究发现,矿石中铁含量低,主要赋存于绿泥石中,无利用价值;钛可有效利用,钛的赋存机制与四大矿集区差异较大。为查清该矿石中钛的赋存状态,采用多种矿物学研究手段对矿石进行了深入研究。研究结果表明:矿石中钛的主要载体矿物为锐钛矿及钛铁矿,分别占总钛的51.39%、21.54%,二者或紧密共生,或独立存在,粒间普遍分布不规则填隙状碳酸盐等脉石矿物;锐钛矿与钛铁矿粒径0.074 mm以上含量低,分别占35.64%、43.92%,细磨单体解离度较差。此外,因矿石发生重度蚀变,少量钛还分布在结晶较差无法有效利用的锐钛矿-绿泥石过度相及榍石等矿物中,即矿石为细粒难选冶、钛赋存状态复杂的钒钛磁铁矿矿石。基于矿石的嵌布特性,最终制定了原矿棒磨后摇床富集钛,预富集产品焙烧-磨矿-酸洗-浮钛-酸浸的混合选钛工艺流程,获得了TiO_(2)品位及回收率均在50%以上的钛精矿,研究成果为该区钛的后续选冶工艺制定提供了新的理论支撑,释放了呆滞钛资源,对同类型矿石综合利用具有重要的参考意义。 展开更多
关键词 锐钛矿型钛矿石 工艺矿物学 赋存状态 理论指标预测
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宜居城市环境品质提升关键问题与研究路径
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作者 郝洛西 张改景 +1 位作者 曹亦潇 邵戎镝 《世界建筑》 2024年第10期80-85,共6页
我国城市已迈入以品质提升为主的转型发展新阶段,宜居环境建设成为城市发展的新理念、新目标。本文介绍了“城市可度量、居民能感知、方法更本土、技术高融合”的城市环境品质提升策略与路线,重点阐述了“宜居城市环境品质评价和提升的... 我国城市已迈入以品质提升为主的转型发展新阶段,宜居环境建设成为城市发展的新理念、新目标。本文介绍了“城市可度量、居民能感知、方法更本土、技术高融合”的城市环境品质提升策略与路线,重点阐述了“宜居城市环境品质评价和提升的本土化理论方法”“城市道路慢行系统与空间环境的适应性改造”“城市声、光、热环境品质的协同提升”与“城市宜居环境综合品质预测模型及应用”四大关键问题,以期构筑“新标尺”,支撑对城市环境品质的精确测度与科学提升。此外,本研究还就数智技术驱动下城市环境品质提升模式的创新与变革进行了探讨。 展开更多
关键词 宜居城市 环境品质 本土理论 慢行系统 声光热环境 城市预测模型 数智驱动
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硫取代氮增强g-C_(3)N_(4)光催化产氢性能 被引量:2
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作者 王海涛 余良浪 +2 位作者 江吉周 Arramel 邹菁 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第5期41-44,共4页
利用取之不尽的太阳能资源进行光催化水裂解制氢是缓解全球能源危机、实现碳中和战略的一项有前景的技术。石墨相氮化碳(g-C_(3)N_(4))因成本低且稳定性高在光催化产氢领域备受关注。然而,纯g-C_(3)N_(4)存在表面积小、电子转移慢、光... 利用取之不尽的太阳能资源进行光催化水裂解制氢是缓解全球能源危机、实现碳中和战略的一项有前景的技术。石墨相氮化碳(g-C_(3)N_(4))因成本低且稳定性高在光催化产氢领域备受关注。然而,纯g-C_(3)N_(4)存在表面积小、电子转移慢、光生载流子复合快等缺陷,产氢性能通常不佳。本研究通过直接热解硫酸铵和三聚氰胺混合物,成功实现硫物种对g-C_(3)N_(4)氮位点的原位取代,开发出一种高效的硫掺杂g-C_(3)N_(4) (S-g-CN)光催化剂。系列结构和光谱表征证实硫的成功掺杂。密度泛函理论的第一性原理计算表明S活性位对氢的吸附吉布斯自由能近乎为零(~0.26 eV),揭示S掺杂在优化H活性中间体吸附和解吸过程中起着重要作用。透射电子显微镜和原子力显微镜测试结果表明,S-g-CN具有超薄的纳米片状结构,其片层厚度约为2.5 nm。随后的氮气吸脱附等温线和光电化学性质测试结果表明,S掺杂不仅可显著增大g-C_(3)N_(4)比表面积,而且还能有效提高其光生电子-空穴对的转移、分离和氧化还原能力。得益于材料良好的结构特性,S-g-CN的光催化产氢速率高达4923 μmol·g^(-1)·h^(-1),是原始g-C_(3)N_(4)的28倍,超越诸多最近报道的其它S掺杂g-C_(3)N_(4)光催化剂。而且,S-g-CN的表观量子效率高达3.64%。本研究除了开发一种高效的光催化剂,还将为高性能g-C_(3)N_(4)基催化剂的设计提供有益借鉴。 展开更多
关键词 理论预测 硫掺杂 g-C_(3)N_(4) 产氢 光催化
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面向全色域转杯纺纱的Kubelka-Munk双常数理论模型构建及颜色预测 被引量:3
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作者 汪燕燕 薛元 +1 位作者 陈宥融 石焕强 《现代纺织技术》 北大核心 2024年第3期1-13,共13页
为了能在色纺纱的纺纱阶段即时调控纱线颜色,减少混色成本,缩短工艺流程,结合三通道数控转杯纺纱的特点构建了全色域网格化混色模型,该模型可在纺纱过程中进行全色域范围内的色相调控、明度调控和彩度调控。为了解决色纺纱的测配色问题... 为了能在色纺纱的纺纱阶段即时调控纱线颜色,减少混色成本,缩短工艺流程,结合三通道数控转杯纺纱的特点构建了全色域网格化混色模型,该模型可在纺纱过程中进行全色域范围内的色相调控、明度调控和彩度调控。为了解决色纺纱的测配色问题,得到与之相匹配的测配色系统,根据来样快速进行计算机测配色,节约成本,结合传统Kubelka-Munk双常数理论模型的特点,从构建的全色域网格化混色模型中选取混合样来进行颜色预测。从传统Kubelka-Munk双常数理论模型颜色预测的结果发现,部分混合样的预测反射率明显低于实际的反射率,针对这个问题,重新构建了新的Kubelka-Munk双常数理论模型来进行颜色预测得到新的预测反射率,并用插值替换的方法,把传统Kubelka-Munk双常数理论模型预测结果中明显低于实际反射率的部分用新的预测反射率替换,得到最终的混合样预测反射率。结果表明:与传统的Kubelka-Munk双常数理论模型预测混合样颜色结果相比,新的Kubelka-Munk双常数理论模型预测颜色并用插值替换法替换后得到的最终的混合样的颜色,色差平均值从1.48降低到1.04,且所有混合样的色差均能控制在2.0以内。该预测方法较传统Kubelka-Munk双常数理论模型具有更好的预测精度,所构建的全色域网格化混色模型和新的Kubelka-Munk双常数理论模型可应用于多基色纤维混色色彩和混合比的预测。 展开更多
关键词 色纺纱 Kubelka-Munk双常数理论 颜色预测 转杯纺纱 反射率
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基于Timoshenko梁模型的变截面体心立方梯度点阵结构力学特性研究
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作者 杨鄂川 谭成帅 +3 位作者 马婧华 李映辉 覃亮 孔垂建 《力学季刊》 CAS CSCD 北大核心 2024年第2期401-410,共10页
针对由变截面杆构成的体心立方(Body-Centered Cubic, BCC)梯度点阵结构,推导了BCC线性变截面弯折杆弯矩的分布表达式,应用于Timoshenko梁理论,得到了梯度点阵结构的力学特性参数化理论预测模型;采用六面体实体单元建立了BCC变截面单胞... 针对由变截面杆构成的体心立方(Body-Centered Cubic, BCC)梯度点阵结构,推导了BCC线性变截面弯折杆弯矩的分布表达式,应用于Timoshenko梁理论,得到了梯度点阵结构的力学特性参数化理论预测模型;采用六面体实体单元建立了BCC变截面单胞单元和梯度点阵结构的有限元模型,完成了仿真分析,验证了理论预测模型的有效性.对于梯度点阵结构则采用3D打印技术并选择316L金属粉末制备试样,开展了准静态压缩力学试验,同时也完成了同样工况下的有限元仿真分析,验证了Timoshenko梁模型对于长径比10以下梯度点阵结构力学特性研究的适用性,最后通过理论模型讨论了不同长径比、单胞尺寸、单胞数量和梯度方向等各种梯度点阵结构力学特性的变化规律.研究结果表明:对于线性变截面弯折杆,文中所推导的弯矩分布更加精确,能有效降低理论解的误差;采用本文中的理论预测模型,若长径比在3.5~8.7区间内,BCC变截面单胞单元及梯度点阵结构的等效弹性模量解的误差在3%以内. 展开更多
关键词 梯度点阵结构 力学特性 TIMOSHENKO梁 理论预测
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基于马尔可夫残差修正灰色模型的轨道质量指数及其分项预测
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作者 邓逸帆 李宵楠 +2 位作者 李政 厚康恒 肖杰灵 《铁道建筑》 北大核心 2024年第6期37-42,共6页
为研究轨道质量指数(Track Quality Index,TQI)及各分项值的变化趋势,本文考虑动检数据的非等时距特征,构建了关于TQI及各分项值的一阶灰色模型。原始数据经过累加变换后,利用最小二乘法求解模型的灰参数,并引入马尔可夫残差修正方法对... 为研究轨道质量指数(Track Quality Index,TQI)及各分项值的变化趋势,本文考虑动检数据的非等时距特征,构建了关于TQI及各分项值的一阶灰色模型。原始数据经过累加变换后,利用最小二乘法求解模型的灰参数,并引入马尔可夫残差修正方法对灰色模型进行修正。通过对比修正前后灰色模型TQI及各分项的输出值(拟合值和预测值)与实测值,验证残差修正对提升模型预测精度和降低预测误差的改善效果。结果表明:经马尔可夫残差修正后,灰色模型TQI及各分项输出值可以较好反映其波动情况;与修正前灰色模型相比,修正后灰色模型TQI预测值与实测值的平均误差由1.59%降至0.89%,整体预测精度由2级提升到1级;TQI各分项预测值与实测值的平均误差由3.18%降至1.42%,整体精度由2~4级提升到1~2级。从降低误差和提升预测精度两方面看,修正后灰色模型的预测效果明显提升。 展开更多
关键词 铁路轨道 TQI预测 理论分析 TQI TQI分项 灰色模型 非等时距 马尔可夫残差修正
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AI-Powered Innovations in High-Tech Research and Development: From Theory to Practice
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作者 Mitra Madanchian Hamed Taherdoost 《Computers, Materials & Continua》 SCIE EI 2024年第11期2133-2159,共27页
This comparative review explores the dynamic and evolving landscape of artificial intelligence(AI)-powered innovations within high-tech research and development(R&D).It delves into both theoreticalmodels and pract... This comparative review explores the dynamic and evolving landscape of artificial intelligence(AI)-powered innovations within high-tech research and development(R&D).It delves into both theoreticalmodels and practical applications across a broad range of industries,including biotechnology,automotive,aerospace,and telecom-munications.By examining critical advancements in AI algorithms,machine learning,deep learning models,simulations,and predictive analytics,the review underscores the transformative role AI has played in advancing theoretical research and shaping cutting-edge technologies.The review integrates both qualitative and quantitative data derived from academic studies,industry reports,and real-world case studies to showcase the tangible impacts of AI on product innovation,process optimization,and strategic decision-making.Notably,it discusses the challenges of integrating AI within complex industrial systems,such as ethical concerns,technical limitations,and the need for regulatory oversight.The findings reveal a mixed landscape where AI has significantly accelerated R&D processes,reduced costs,and enabled more precise simulations and predictions,but also highlighted gaps in knowledge transfer,skills adaptation,and cross-industry standardization.By bridging the gap between AI theory and practice,the review offers insights into the effectiveness,successes,and obstacles faced by organizations as they implement AI-driven solutions.Concluding with a forward-looking perspective,the review identifies emerging trends,future challenges,and promising opportunities inAI-poweredR&D,such as the rise of autonomous systems,AI-driven drug discovery,and sustainable energy solutions.It offers a holistic understanding of how AI is shaping the future of technological innovation and provides actionable insights for researchers,engineers,and policymakers involved in high-tech Research and Development(R&D). 展开更多
关键词 Deep learning high-tech research and development theoretical models practical applications neural networks predictive analytics innovation strategies
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仿生树状分形薄壁结构的耐撞性研究
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作者 吴斌 李伟伟 +1 位作者 张继鹏 王玥 《山东理工大学学报(自然科学版)》 2024年第2期35-41,55,共8页
为提高薄壁管结构的耐撞性,受树枝生长规律的启发,设计了两类树状分形的薄壁多胞结构。根据简化的超折叠单元理论,针对轴向压缩工况,建立仿生薄壁管的平均冲击力理论模型,采用有限元数值模拟技术,研究分形结构对薄壁结构耐撞性的影响。... 为提高薄壁管结构的耐撞性,受树枝生长规律的启发,设计了两类树状分形的薄壁多胞结构。根据简化的超折叠单元理论,针对轴向压缩工况,建立仿生薄壁管的平均冲击力理论模型,采用有限元数值模拟技术,研究分形结构对薄壁结构耐撞性的影响。结果表明:理论模型可以有效地预测仿生薄壁管的平均冲击力,树状分形设计能够促进薄壁结构的变形稳定,高阶仿生薄壁管在比吸能、载荷效率等方面优于单胞方管,且随着分形阶数的增加,仿生管的能量吸收能力和变形稳定性进一步提升。 展开更多
关键词 薄壁结构 耐撞性 理论预测 仿生结构 分形结构
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隧道爆破振动中掏槽段的波形预测方法
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作者 望远福 李云赫 +1 位作者 赵岩 范杰林 《中国测试》 CAS 北大核心 2024年第10期150-156,共7页
为探讨隧道爆破振动响应的分布特征,对掏槽爆破诱发的爆破振动波形展开预测。基于等效的球形爆源理论,引入一种地表爆破振动波形的预测方法,首次将频率的影响纳入爆破振动波形的预测研究中,推导得到等效球形爆破荷载作用下的地表爆破振... 为探讨隧道爆破振动响应的分布特征,对掏槽爆破诱发的爆破振动波形展开预测。基于等效的球形爆源理论,引入一种地表爆破振动波形的预测方法,首次将频率的影响纳入爆破振动波形的预测研究中,推导得到等效球形爆破荷载作用下的地表爆破振动波形的符号表达式。以此为基础,构造形式简洁的爆破振动波形预测函数。依托具体隧道爆破的现场监测数据对预测函数的可靠性进行验证。结果表明:理论波形与实测波形在爆破振动曲线总体趋势上表现出良好的一致性。二者对应的质点峰值速度与振动周期基本相同。这种对比结果可验证该文引入方法的可行性。 展开更多
关键词 隧道爆破振动 等效球形药包 波形预测 理论推导
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基于三点弯曲试验的混凝土叠合梁跨中挠度研究
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作者 胡运 郭瑞 +1 位作者 高振博 苏悦琦 《建筑技术》 2024年第13期1634-1636,共3页
预制装配式结构采用工厂预制与现场安装相结合的方式,可降低环境污染,减少资源浪费,其中装配式混凝土结构常采用叠合梁、叠合板,叠合结构整体性和抗震性能好。选取某构件厂成品叠合梁(YKL2a-XS-1)进行了三点弯曲试验,获得叠合梁荷载挠... 预制装配式结构采用工厂预制与现场安装相结合的方式,可降低环境污染,减少资源浪费,其中装配式混凝土结构常采用叠合梁、叠合板,叠合结构整体性和抗震性能好。选取某构件厂成品叠合梁(YKL2a-XS-1)进行了三点弯曲试验,获得叠合梁荷载挠度曲线,分析叠合梁跨中挠度与荷载的关系;依据梁跨中挠度计算公式,计算叠合梁跨中挠度。叠合梁加载变形特点与适筋梁受弯性能相似,加载期间,叠合面无滑移,预制再生混凝土与后浇普通混凝土整体性较好;随着荷载增加,叠合梁的挠度增加,跨中挠度实测值增加幅度最大,跨中挠度未超过设计限值,叠合梁满足工程实际中构件的延性要求;依据梁跨中挠度计算公式得到的跨中挠度理论值高于真实值。 展开更多
关键词 混凝土叠合梁 跨中挠度 变形 理论预测
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基于热阻法的多层热障涂层叶片隔热预测模型研究
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作者 何佳宁 艾延廷 +2 位作者 关鹏 刘言明 姚玉东 《推进技术》 EI CAS CSCD 北大核心 2024年第10期159-168,共10页
为实现有热障涂层(TBCs)的叶片表面温度预测,开展基于热阻法的热障涂层隔热理论分析,建立了TBCs隔热理论模型,模型包括有热障涂层叶片表面温度预测式(VT-TBCs)和热障涂层隔热温度预测式(IT-TBCs),并分别基于IT-TBCs和仿真分析了陶瓷层(... 为实现有热障涂层(TBCs)的叶片表面温度预测,开展基于热阻法的热障涂层隔热理论分析,建立了TBCs隔热理论模型,模型包括有热障涂层叶片表面温度预测式(VT-TBCs)和热障涂层隔热温度预测式(IT-TBCs),并分别基于IT-TBCs和仿真分析了陶瓷层(TC)、粘结层(BC)的厚度、导热系数对隔热温度的影响。结果表明:与数值仿真结果相比,VT-TBCs的计算结果最大误差不超过3%,平均误差为0.65%。通过IT-TBCs分析可知,导热系数小于0.5 W(/m·K)时,热障涂层厚度与隔热温度趋近对数关系,当导热系数大于0.5 W(/m·K)时,热障涂层厚度与隔热温度趋近线性关系,BC层的导热系数与厚度对隔热温度基本无影响。仿真分析结果与IT-TBCs分析结果一致。 展开更多
关键词 热障涂层 热阻法 隔热理论模型 温度预测 导热系数
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