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Earthquake Engineering and Engineering Vibration 2017年第2期16卷 297-309页

作者： JASC Jayasinghe M. Hori mr riaz MLL Wijerathne T Ichimura Earthquake Research Institute University of Tokyo Tokyo 113-0032 Japan

In this study, a new method for conversion of solid finite element solution to beam finite element solution is developed based on the meta-modeling theory which constructs a model consistent with continuum mechanics. The proposed method is rigorous and efficient compared to a typical conversion method which merely computes surface integration of solid element nodal stresses to obtain cross-sectional forces. The meta-modeling theory ensures the rigorousness of proposed method by defining a proper distance between beam element and solid element solutions in a function space of continuum mechanics. Results of numerical verification test that is conducted with a simple cantilever beam are used to find the proper distance function for this conversion. Time history analysis of the main tunnel structure of a real ramp tunnel is considered as a numerical example for the proposed conversion method. It is shown that cross-sectional forces are readily computed for solid element solution of the main tunnel structure when it is converted to a beam element solution using the proposed method. Further, envelopes of resultant forces which are of primary importance for the purpose of design, are developed for a given ground motion at the end.

关键词： meta-modeling theory finite element method solid and beam element models continuum mechanics structural mechanics

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天然裂缝性油藏中的散射传质模拟

石油勘探开发情报 1994年第3期 63-73页

作者： riaz.,mr 冯为民

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DREAMBUILDERS

小学生时代（大嘴英语） 2024年第3期 30-35页

作者： mr.Duck 不详

英文原名:Dreambuilders中文译名:梦境历险记掌握关键词:dream梦剧情简介爸爸妈妈离婚后,米娜(Minna)跟着爸爸一起生活,两个人的日子平静而幸福,米娜还养了一只小仓鼠……直到爸爸再婚,家里多了两位新成员——爸爸的新妻子海莲娜(Helena... 详细信息

英文原名:Dreambuilders中文译名:梦境历险记掌握关键词:dream梦剧情简介爸爸妈妈离婚后,米娜(Minna)跟着爸爸一起生活,两个人的日子平静而幸福,米娜还养了一只小仓鼠……直到爸爸再婚,家里多了两位新成员——爸爸的新妻子海莲娜(Helena)和她的女儿珍妮(Jenny)。

关键词：历险记中文译名米娜

西安,何谓十三朝古都?千年建城史带来的荣光

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城市地理 2024年第5期 18-27页

作者： Rae 高鑫(图) mr.Carrot(图) 左小朵(图) 虎子(图) 摄图网

甲辰龙年春节,春晚西安分会场干人齐诵《将进酒》的画面,让“顶流”城市西安的文旅热度再上一层楼。在这里,跨越时间长河的西安城墙,延续着数干年的历史文脉;大唐不夜城里衣翻飞的丽人,让人恍若走进《簪花仕女图》的画中;“最西安”的... 详细信息

甲辰龙年春节,春晚西安分会场干人齐诵《将进酒》的画面,让“顶流”城市西安的文旅热度再上一层楼。在这里,跨越时间长河的西安城墙,延续着数干年的历史文脉;大唐不夜城里衣翻飞的丽人,让人恍若走进《簪花仕女图》的画中;“最西安”的标识秦兵马,则见证了王朝霸业下的沧桑巨变……历经十三朝兴衰,在如今的西安,仍能窥见旧时长安的繁盛模样。

关键词：西安城墙《将进酒》一层楼历史文脉十三朝古都沧桑巨变

Influence of Non-Uniform Temperature Distribution on Metallic Charge Length on Energy and Force Parameters During Groove-Rolling

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Journal of Iron and Steel Research International 2012年第8期19卷 17-24页

作者： mróz Sebastian Czestochowa University of Technology

Change in the temperature of band over its length, associated with the stock being non-uniformly heated in the furnace, influences the variations in the magnitudes of energy-force parameters. Using the FEM (Finite Element Model) programs for the computation of the values of the energy-force parameters can take into account the distribution of temperature over the band length. The mathematical model of the computer program Forge2008 was used to theoretically examine the energy-force parameters and plastic metal flow in the roughing stands of the continuous rolling mill. The results of experimental investigation of influence of the non-uniform temperature distribution were presented on the metallic charge length on the energy and force parameters and dimensions of the band during round bars rolling. Thermovision monitoring energy and force parameters monitoring were carried out in continuous rolling mill D350 in one of the Polish industrial plants. On the basis of obtained results, it could be stated that non-uniform distribution of temperatures along the charge length causes local increase of energy and force parameters values and also such distribution affects the local increase of the width of rolled band. The rolling process of charge with non-uniform distribution of temperature could lead to exceeding required dimensional tolerances of the final products.

关键词： groove-rolling energy parameter force parameter numerical technique FEM

从兵马俑到大唐不夜城 “网红”古都的出圈之路

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城市地理 2024年第5期 28-37页

作者：辰于惊蛰高鑫(图) 虎子(图) mr.Carrot(图) 赵泽颖(图) 徐莹滢(图) 不详

“网红”一词随着当代大众传播和消费主义浪潮的兴起,逐步走进大众视野。过去几年,西安人见到了太多陡然出现又迅速销声匿迹的地方,从吸引外地游客的大唐不夜城、永兴坊,到针对本地年轻人的东柳巷和民乐园,西安的热度甚器尘上。晨钟暮鼓... 详细信息

“网红”一词随着当代大众传播和消费主义浪潮的兴起,逐步走进大众视野。过去几年,西安人见到了太多陡然出现又迅速销声匿迹的地方,从吸引外地游客的大唐不夜城、永兴坊,到针对本地年轻人的东柳巷和民乐园,西安的热度甚器尘上。晨钟暮鼓间,这座干年古都始终傲然位立,迎接着汹涌的人潮。

关键词：兵马俑消费主义大众传播网红民乐园外地游客古都西安

Ability for Self-Pelletization of Iron Ores and Magnetite Concentrates

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Journal of Iron and Steel Research International 2011年第6期18卷 1-7页

作者： Francik Przemysaw Jan mróz Czestochowa University of Technology Czestochowa 42-200Poland

A procedure for evaluating the susceptibility of raw materials for the process of sintering of iron ore mixes is presented. The procedure relies on the evaluation of the amount and quality of the finest grain fraction. The method is based on determination of particular grain fractions. For the grain less than 0.15 mm, the determination of the a- mount is performed using an IPS （Infrared Particles Sizer） grain size analyzer and for the grain larger than 0.15 ram, the fraction is determined using the （wet and dry） screening methods. This allows for quantity assessment of the quality of material in terms of its susceptibility to self-pelletizing by calculating Total Ability for SelPPelletizing （TASP） index fT. The presented method, in combination with the grain size and chemical analyses, can serve for evaluation of suitability of raw material and mixes for the sintering process. Furthermore, the TASP index for 10 types of iron ores and concentrates was determined. The usability of the TASP index was verified by determination of its impact on yield of sintering process both in laboratory and in industry scale.

关键词： iron ore concentrate grain composition pelletization process sintering process productivity

Prediction of XRF analyzers error for elements on-line assaying using Kalman Filter

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International Journal of Mining Science and Technology 2012年第4期22卷 595-601页

作者： Nakhaei F Sam A Mosavi mr Nakhaei A Department of Mining Engineering Shahid Bahonar Kerman UniversityKerman 761886-8366Iran Department of Electrical Engineering Iran University of Science and TechnologyTehran 16846-13114Iran Department of Electrical Engineering Birjand UniversityBirjand 97175-376Iran

Determination of chemical elements assay plays an important role in mineral processing *** factor is used to control process accuracy,recovery calculation and plant *** new assaying methods including chemical methods,X-ray fluorescence and atomic absorption spectrometry are advanced and ***,in some applications,such as on-line assaying process,high accuracy is *** this paper,an algorithm based on Kalman Filter is presented to predict on-line XRF *** research has been carried out on the basis of based the industrial real data collection for evaluating the performance of the presented *** measurements and analysis for this study were conducted at the Sarcheshmeh Copper Concentrator Plant located in *** quality of the obtained results was very satisfied;so that the RMS errors of prediction obtained for Cu and Mo grade assaying errors in rougher feed were less than 0.039 and 0.002 and in final flotation concentration less than 0.58 and 0.074,*** results indicate that the mentioned method is quite accurate to reduce the on-line XRF errors measurement.

关键词： PredictionAccuracyX-ray fluorescence Kalman FilterAssayingError

In-situ Monitoring the Setting Behavior of Foamed Concrete Using Ultrasonic Pulse Velocity Method

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Journal of Wuhan University of Technology(Materials Science) 2013年第6期28卷 1146-1154页

作者： SHE Wei ZHANG Yunsheng JONES mr GUO Panpan Jiangsu Key laboratory for Construction Materials Southeast University Concrete Technology Unit Division of Civil EngineeringUniversity of Dundee

The applicability of ultrasonic pulse velocity （UPV） method to in-situ monitor setting and hardening process of foamed concrete （FC） was systematically investigated. The UPVs of various FC pastes were automatically and continuously measured by a specially designed ultrasonic monitoring apparatus （UMA）. Ultrasonic tests were performed on FC mixtures with different density （300, 500, 800 and 1 000 kg/m3）, and different fly ash contents （0%, 20%, 40% and 60%）. The influence of curing temperatures （20, 40, 60 and 80~C） was also studied. The experimental results show that three characteristic stages can be clearly identified during the setting process of an arbitrary FC paste： dormant stage, acceleration stage, and deceleration stage. Wet density, fly ash content, and curing temperature have great impact on setting behavior. A stepwise increase of the wet density results in shorter dormant stage and larger final UPV. Hydration reaction rate is obviously promoted with an increase in curing temperature. However, the addition fly ash retards the microstn,lcture formation. To aid in comparing with the ultrasonic results, the consistence spread test and Vicat needle test （VNT） were also conducted. A correlation between ultrasonic and VNT results was also established to evaluate the initial and final setting time of the FC mixtures. Finally, certain ranges of UPV with reasonable widths were suggested for the initial and final setting time, respectively.

关键词： foamed concrete (FC) early age setting behavior ultrasonic monitoring setting time consistence

Experimental investigation on phase transformation type micropump

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Chinese Science Bulletin 2002年第6期47卷 518-522页

作者： Li, ZX Wang, mr Tan, LY Tsing Hua Univ Dept Engn Mech Beijing 100084 Peoples R China

The phase transformation type micropump without moving parts was experimentally studied in this note. To analyze the pumping mechanism of the micropump, a simplified physical model was presented. The experimental results indicate that the pump characteristic is mainly dependent on the heating and cooling conditions. For a given system, there exist an optimal combination of heating current and switch time with which the flow rate reaches maximum. Comparing with the natural cooling, the forced con-vective cooling needs larger heating current to obtain the same flow rate. In our experiments, the maximum flow rate is 33μL/min when the inner diameter of the micropump is 200μm, and the maximum pumping pressure reaches over 20 kPa. The theoretical analysis shows that the pumping mechanism of the micropump mainly lies in the large density difference between liquid and gas phases and the effect of gas chocking.

关键词： micropump phase transformation pumping character-istic.