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短周期地震计回转摆敏感元件优化设计与仿真 被引量:1
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作者 姚振静 段艳丽 +2 位作者 范业彤 洪利 高强 《科学技术与工程》 北大核心 2018年第31期23-29,共7页
为拓展地震计有效频带范围,对回转摆进行理论分析,得出回转摆频率特性与敏感元件簧片尺寸计算公式。采用ANSYS仿真软件建立回转摆有限元仿真模型,对敏感元件进行模态和静态分析,并对敏感元件簧片尺寸进行优化设计。采用游击力锤激励法... 为拓展地震计有效频带范围,对回转摆进行理论分析,得出回转摆频率特性与敏感元件簧片尺寸计算公式。采用ANSYS仿真软件建立回转摆有限元仿真模型,对敏感元件进行模态和静态分析,并对敏感元件簧片尺寸进行优化设计。采用游击力锤激励法对优化前后的回转摆进行振动模态实验,测试结果表明回转摆模态频率误差在1. 01%以内,验证了优化回转摆仿真模型的合理性。采用正弦标定法测量优化前后地震计的频率特性,实验结果表明:相比于传统敏感元件地震计,优化后回转摆一阶与二阶固有频率差提高了22. 48%,地震计频带范围拓展了21. 42%,为地震计扩展频带范围提供了理论依据。 展开更多
关键词 周期地震 回转摆 敏感元件 固有频率
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短周期与宽频带数字地震计记录波形相关分析 被引量:3
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作者 李霞 张志慧 +1 位作者 周彦文 刘希强 《内陆地震》 2010年第1期50-56,共7页
为了研究短周期与宽频带数字地震观测系统的一致性,分别对山东地震台网青岛、济南、荣成、五莲、烟台的5个同一摆墩上安装的两套观测系统记录的同一地震事件波形资料进行了相关性分析。先将宽频带记录通过等波纹带通滤波器进行频带为1... 为了研究短周期与宽频带数字地震观测系统的一致性,分别对山东地震台网青岛、济南、荣成、五莲、烟台的5个同一摆墩上安装的两套观测系统记录的同一地震事件波形资料进行了相关性分析。先将宽频带记录通过等波纹带通滤波器进行频带为1~20Hz的滤波处理,再将短周期记录进行过采样处理,实现与宽频带记录的采样率一致。分析表明,宽频带和短周期地震计记录近震、地方震和非天然近距离地震波形在形态上一致,地震波形的振幅和相位存在较好相似性,震中距越近地震波形振幅和相位的相似度越高,宽频带和短周期地震计得到速度震级间差别不大,一致性较好。 展开更多
关键词 地震波 周期数字地震 宽频带数字地震 相关性分析
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短杆单极质谱计性能研究
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作者 徐波 刘学博 +3 位作者 杨春信 周抗寒 黄刚 邓一兵 《质谱学报》 EI CAS CSCD 2004年第B10期227-228,共2页
The performances of the monopole mass spectrometer were analyzed that it had high resolving power and focusing property. The monopole mass spectrometer whose electrode length was 100mm and r0=5mm had been designed and... The performances of the monopole mass spectrometer were analyzed that it had high resolving power and focusing property. The monopole mass spectrometer whose electrode length was 100mm and r0=5mm had been designed and manufactured. The resolving power and mass range of it had been measured. The researching results indicated: The mass range of the device was 223. The resolving power achieved 30 measured at 10% peak height of the N2^+. The device could he used in residual gas analysis. 展开更多
关键词 杆单极质谱 性能 工作原理 质量范围 分辨率
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对改进定期储蓄计息办法的意见
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作者 吴凡 《浙江金融》 1985年第10期38-38,共1页
现行定期储蓄利率,用约定存期和实际存期两个依据分档计息,调动了储户的积极性,对国家银行积聚资金支持生产和流通有良好作用。但由于现行储蓄章程规定可以提前支取,约定存期对储户没有实际约束力,往往造成原定存期长而提前支取的利率,... 现行定期储蓄利率,用约定存期和实际存期两个依据分档计息,调动了储户的积极性,对国家银行积聚资金支持生产和流通有良好作用。但由于现行储蓄章程规定可以提前支取,约定存期对储户没有实际约束力,往往造成原定存期长而提前支取的利率,会比原定存期短而逾期支取的利率要高,这样,计算方法似欠合理。为此,建议对定期储蓄的提前支取或延期提取的利率,可以改为一律按实际存期长短计给利息,比较合理,这样。 展开更多
关键词 定期储蓄 短计 章程规定 算方法 对鼓
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专业银行转变为商业银行的若干问题
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作者 石雷 《内蒙古金融研究》 1994年第4期4-6,共3页
如何实事求是而又积极稳妥的把专业银行转变为商业银行,实现政策性与商业性金融业务分离,是加快金融体制改革的重要环节,本文就此问题谈些看法。一、哪些银行是专业银行目前我国的银行(不含外资及中外合资银行)。
关键词 商业性金融 中信实业银行 浦东发展 存款者 中国投资银行 信贷 信用方式 债权债务 企业化经营 短计
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Optimizing Efficient Micropropagation System of Rhododendron Brachycarpum D. Don by Uniform Design Method
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作者 姜云天 陈艳秋 +2 位作者 顾地周 李玉梅 曲柏宏 《Agricultural Science & Technology》 CAS 2009年第5期49-51,共3页
[Objective] The study was conducted to establish a high efficient micropropagation system for Rhododendron Brachycarpum D. Don and realize the high efficiency in vitro micropropagation of R. brachycarpum. [ Method ] Y... [Objective] The study was conducted to establish a high efficient micropropagation system for Rhododendron Brachycarpum D. Don and realize the high efficiency in vitro micropropagation of R. brachycarpum. [ Method ] Young stems of R. brachycarpum were used as explants, suitable medium compositions for axillary bud growing and rooting were screened through uniform design exPeriments. [ Result] MS (modified) + IAA 0,15 mg/ L + IBA 0.30 mg/L + GA3 3.00 mg/L was the most suitable medium with the regeneration rate of 92%. Stems each with one node were cut from regenerated shoots and cultured for propagation, the proliferative multiple was over 45 within one culture period of 35 d. [ Conclusion] High efficient micropropagation system of R. brachycarpum has been successfully established, which provides some basis for development and utilization and industrial seedling growth of the alpine rhododendron in Changbai Mountain northeast China. 展开更多
关键词 Rhododendron Brachycarpum D. Don MICROPROPAGATION Uniform Design
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基于检波器的短周期地震计的改进 被引量:4
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作者 张晓鹏 李世维 +1 位作者 王同东 靳平 《地球物理学进展》 CSCD 北大核心 2014年第5期2466-2471,共6页
基于检波器的Lippmann式短周期地震计利用内部电路提供的高阻尼,拓展检波器的带宽,使其符合流动地震观测的要求.但这种地震计的温度稳定性差且灵敏度低.针对上述缺点,本文根据传感器性能受温度影响的理论模型和前置放大器的设计原理,提... 基于检波器的Lippmann式短周期地震计利用内部电路提供的高阻尼,拓展检波器的带宽,使其符合流动地震观测的要求.但这种地震计的温度稳定性差且灵敏度低.针对上述缺点,本文根据传感器性能受温度影响的理论模型和前置放大器的设计原理,提出了一种改进的方法:使用负温度系数的温度补偿网络和一种新型的前置放大器来改善地震计的性能.改进的基于检波器的短周期地震计的传递性能在很大的温度范围内不受温度的影响,具有较高的灵敏度和较低的噪声水平. 展开更多
关键词 检波器 周期地震 温度稳定性 高灵敏度
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TENSILE STRENGTH OF RANDOM ORIENTED SHORT FIBER COMPOSITE
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作者 唐德敏 许晓秋 +1 位作者 冯建新 方洞浦 《Transactions of Tianjin University》 EI CAS 1998年第2期59-62,共4页
This paper shows a calculation model and a method for predicting the tensile strength of the random distributed short fiber composite.On the basis of Renjie Mao's model,the longitudinal tensile strength of the ali... This paper shows a calculation model and a method for predicting the tensile strength of the random distributed short fiber composite.On the basis of Renjie Mao's model,the longitudinal tensile strength of the aligned short fiber composite is formulated.Considering the transverse tensile strength and in plane shear strength of the unidirectional fiber composite,and the stress transformation relations of two couples of axes,the stress of the unidirectional fiber composite when it is loaded at an arbitrary angle is obtained.With the aid of an equivalence relation,the calculation formulation of the tensile strength of the random short fiber reinforced composite is deduced. 展开更多
关键词 random short fiber composite tensile strength calculation model
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Steiner Tree Based Optimal Resource Caching Scheme in Fog Computing 被引量:11
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作者 SU Jingtao LIN Fuhong +1 位作者 ZHOU Xianwei Lü Xing 《China Communications》 SCIE CSCD 2015年第8期161-168,共8页
Fog Computing is a new platform that can serve mobile devices in the local area. In Fog Computing, the resources need to be shared or cached in the widely deployed Fog clusters. In this paper, we propose a Steiner tre... Fog Computing is a new platform that can serve mobile devices in the local area. In Fog Computing, the resources need to be shared or cached in the widely deployed Fog clusters. In this paper, we propose a Steiner tree based caching scheme, in which the Fog servers, when caching resources, first produce a Steiner tree to minimize the total path weight(or cost) such that the cost of resource caching using this tree could be minimized. Then we give a running illustration to show how the Fog Computing works and we compare the traditional shortest path scheme with the proposed one. The outcome shows that the Steiner tree based scheme could work more efficiently. 展开更多
关键词 steiner Tree resource caching fogcomputing ARCHITECTURE
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Liquid Flow Field on Evaporator of Wiped Short Path Distillation——Experimental Results and Computer Simulation  被引量:1
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作者 许松林 王军武 +1 位作者 向爱双 徐世民 《Transactions of Tianjin University》 EI CAS 2005年第1期6-10,共5页
Short path distillation (SPD) is a kind of high vacuum distillation method, which is suitable for the separation of high boiling, heat sensitivity and viscidity products.In this paper,through measuring the phase-avera... Short path distillation (SPD) is a kind of high vacuum distillation method, which is suitable for the separation of high boiling, heat sensitivity and viscidity products.In this paper,through measuring the phase-averaged velocity distributions with a conditional sampling method of the particle imaging velocimetry (PIV), the liquid flow field that affects the heat and mass transfer of evaporating thin-film in an SPD evaporator is investigated.Measured results show that the flow velocities decrease rapidly apart from the wiper at different wiper velocities, the maximum velocity appears before wipers, and the quicker the wiping, the larger the flow velocity. Meanwhile, the evaluation of numerical calculations is carried out.The measured velocity distributions indicate clearly the effect of the wiper both on the flow field along its moving direction and on the vortices behind the wiper.Simulation data show that the performance of liquid flow field on the heating surface not only agrees with the experimental results well,but also can give further more information, such as the distribution of turbulent kinetic energy.In this study,turbulent kinetic energy mainly distributes before wipers and laminar flow appears far away from the wipers. 展开更多
关键词 short-path distillation turbulent liquid film particle imaging velocimetry(PIV): evaporator
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Electro-Discharge Fine Truing of Metal-Bonded Fine-Grain Diamond Wheel Based on Real-Time Monitoring 被引量:2
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作者 金卫东 任成祖 +1 位作者 华瑾海 王太勇 《Transactions of Tianjin University》 EI CAS 2005年第3期176-182,共7页
A data acquisition system based on LabVIEW is designed and implemented, and electro-discharge(ED) fine truing of metal-bonded fine-grain diamond wheel based on real-time monitoring is researched. Real-time monitoring ... A data acquisition system based on LabVIEW is designed and implemented, and electro-discharge(ED) fine truing of metal-bonded fine-grain diamond wheel based on real-time monitoring is researched. Real-time monitoring not only makes efficient impulse specification of ED truing easily obtained, but also is good for timely identifying no-load, avoiding short circuit and arc discharge phenomena and then for obtaining normal machining state. ED fine truing of the fine-grain wheel includes two steps: rough truing for high efficiency and fine truing for high precision. Final ED truing precision and efficiency not only depend on electric process specification, but also is concerned with electrode shape, insulated performance of operating fluid and vertical feed quantity value and frequency. Experiments indicate that ED fine truing based on real-time monitoring can improve the truing precision and efficiency. Average machining efficiency of W10 wheel is about 0.95 μm/min; the final run-out by ED truing is less than 2 μm. 展开更多
关键词 metal-bonded diamond wheel electro-discharge truing(ED truing) real-time monitor- ing short-circuit current
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3D structure parameterization design and modeling for irregular structure of stope bottom 被引量:3
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作者 曾庆田 Wang Liguan 《High Technology Letters》 EI CAS 2016年第1期55-62,共8页
Stope mining design is a very important and complicated task in daily production design and technical management of an underground mine.Based on workface technology and human-computer interaction technology,this study... Stope mining design is a very important and complicated task in daily production design and technical management of an underground mine.Based on workface technology and human-computer interaction technology,this study introduces a method of 3D parametric design for the irregular structure of stope bottoms,and focuses on solving technical problems in surface modeling of stope bottom structure.Optimization of the minimum span length algorithm(MSLA) and the shortest path search algorithm(SPSA) is conducted to solve the problem of contour-line based instant modeling of stope bottom structures,which makes possible the 3D parametric design for irregular structure of stope bottom.Implementation process and relevant methods of the proposed algorithms are also presented.Feasibility and reliability of the proposed modeling method are testified in a case study.In practice,the proposed 3 D parameterization design method for irregular structure stope bottom proves to be very helpful to precise 3D parametric design.This method is capable of contributing to improved efficiency and precision of stope design,and is worthy of promotion. 展开更多
关键词 irregular stope bottom structure STOPE structure parameterization design surface reconstruction modeling
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Computer Aided Design of Geodesic Forms
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作者 Dimitra Tzourmakliotou 《Journal of Civil Engineering and Architecture》 2012年第2期131-149,共19页
Geodesic forms constitute an important family of structural systems. They are efficient and appealing and are employed frequently for dome structures. Data generation for geodesic forms has always been a difficult tas... Geodesic forms constitute an important family of structural systems. They are efficient and appealing and are employed frequently for dome structures. Data generation for geodesic forms has always been a difficult task, from the days of hand data generation using tables of coefficients to today's specially written computer programs with many limitations and shortcomings. Formex algebra is a mathematical system which is ideally suited for data generation and configuration processing. The objective of the present paper is to introduce the concepts of formex algebra through which data generation for polyhedric and geodesic forms can be handled with ease and elegance. 展开更多
关键词 Geodesic Form formex algebra polyhedra structural configuration retronorm.
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Exact Solutions to Short Pulse Equation
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作者 FU Zun-Tao ZHENG Ming-Hua LIU Shi-Kuo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第3期395-396,共2页
In this paper, dependent and independent variable transformations are introduced to solve the short pulse equation. It is shown that different kinds of solutions can be obtained to the short pulse equation.
关键词 Jacobian elliptic function the short pulse equation TRANSFORMATION
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Analysis of the characteristics of gravity waves during a local rainstorm event in Foshan,China 被引量:1
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作者 WANG Xiujuan LEI Hengchi +3 位作者 FENG Liang ZHU Jiangshan LI Zhaoming JIANG Zhongbao 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第2期163-170,共8页
A detailed analysis of the dynamic frequency spectrum characteristics of gravity waves(GWs)during a local heavy rainfall event on 20–21 November 2016 in Foshan,China,is presented.The results of this analysis,which wa... A detailed analysis of the dynamic frequency spectrum characteristics of gravity waves(GWs)during a local heavy rainfall event on 20–21 November 2016 in Foshan,China,is presented.The results of this analysis,which was based on high-precision microbarograph data,indicate that GWs played a key role in generating the rainstorm.The GWs experienced two intermittent periods of amplitude enhancement and period widening.The largest amplitudes of the GWs were 80–160 Pa,with a corresponding period range of 140–270 min,which were approximately 4 h ahead of the rainstorm.The severe storms appeared to affect the GWs by augmenting the wave amplitudes with center amplitudes of approximately 80–100 Pa and periods ranging between 210 and 270 min;in particular,the amplitudes increased to approximately 10 Pa for GWs with shorter periods(less than 36 min).The pre-existing large-amplitude GWs may be precursors to severe storms;that is,these GWs occurred approximately 4 h earlier than the time radars and satellites identified convections.Thus,these results indicate that large-amplitude GWs constitute a possible mechanism for severe-storm warning. 展开更多
关键词 Gravity wave microbarograph dynamic characteristics short period long period AMPLITUDE
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Short-term effectiveness of radiochemoembolization for selected hepatic metastases with a combination protocol 被引量:2
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作者 Shahram Akhlaghpoor Alireza Aziz-Ahari +3 位作者 Mahasti Amoui Shahnaz Tolooee Hossein Poorbeigi Shahab Sheybani 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第37期5249-5259,共11页
AIM: To introduce the combination method of radio- chemoembolization for the treatment of selected he- patic metastases. METHODS: Twenty patients with biopsy proven hepat- ic metastases were selected from those who ... AIM: To introduce the combination method of radio- chemoembolization for the treatment of selected he- patic metastases. METHODS: Twenty patients with biopsy proven hepat- ic metastases were selected from those who underwent transarterial radiochemoembolization, a novel combina- tion protocol, between .lanuary 2009 and July 2010. Patients had different sources of liver metastasis. The treatment included transarterial administration of three chemotherapeutic drugs (mitomycin, doxorubicin and cisplatin), followed by embolization with large (50-150 μm) radioisotope particles of chromic 32R Multiphasic computer tomography or computer tomography stud- ies, with and without contrast medium injections, were performed for all patients for a short-term period before and after the treatment sessions. The short-term effec- tiveness of this procedure was evaluated by modified response evaluation criteria in solid tumors (mRECIST), which also takes necrosis into account. The subjective percentage of necrosis was also assessed. The re- sponse evaluation methods were based on the changes in size, number, and the enhancement patterns of the lesions between the pre- and post-treatment imaging studies. RESULTS: Patients had liver metastasis from colorectal carcinomas, breast cancer, lung cancer and carcinoid tumors. The response rate based on the mRECIST criteria was 5% for complete response, 60% for par- tial response, 10% for stable disease, and 25% for progressive disease. Regarding the subjective necrosis percentage, 5% of patients had complete response, 50% had partial response, 25% had stable disease, and 20% had progressive disease. Based on traditional RECIST criteria, 3 patients (15%) had partial response, 13 patients (65%) had stable disease, and 4 patients (20%) had disease progression. In most patients, colorectal carcinoma was the source of metastasis (13 patients). Based on the mRECIST criteria, 8 out of these 13 patients had partial responses, while one remained stable, and 5 showed progressive disease. We also had 5 cases of breast cancer metastasis which mostly remained stable (4 cases), with only one partial response after the procedure. Six patients had bilobar involvement; three of them received two courses of radiochemoembolization. The follow up imaging study of these patients was performed after the second ses- sion. In the studied patients there was no evidence of extrahepatic occurrence, including pulmonary radioac- tive deposition, which was proven by Bremsstrahlung scintigraphy performed after the treatment sessions. For the short-term follow-ups for the 2 mo after the therapy, no treatment related death was reported. The mostly common side effect was post-embolization syndrome, presented as vomiting, abdominal pain, and fever. Nineteen (95%) patients experienced this syndrome in different severities. Two patient had asci- tes (with pleural effusion in one patient) not related to hepatic failure. Moreover, no cases of acute liver failure, hepatic infarction, hepatic abscess, biliary necrosis, tu- mor rupture, surgical cholecystitis, or non-targeted gut embolization were reported. Systemic toxicities such as alopecia, marrow suppression, renal toxicity, or cardiac failure did not occur in our study group. CONCLUSION: Radiochemoembolization is safe and effective for selected hepatic metastases in a short- term follow-up. Further studies are required to show the long-term effects and possible complications of this approach. 展开更多
关键词 Hepatic metastasis Radiochemoemboliza-tion Phosphorus radioisotopes TREATMENT OUTCOME
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Parameters estimate of recurrent quantum stochastic filter for time variant frequency periodic signals
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作者 ZHOU Li-chun JIN Fu-jiang +1 位作者 WU Hao-han WANG Bo 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第12期3328-3337,共10页
Designing optimal time and spatial difference step size is the key technology for quantum-random filtering(QSF)to realize time-varying frequency periodic signal filtering.In this paper,it was proposed to use the short... Designing optimal time and spatial difference step size is the key technology for quantum-random filtering(QSF)to realize time-varying frequency periodic signal filtering.In this paper,it was proposed to use the short-time Fourier transform(STFT)to dynamically estimate the signal to noise ratio(SNR)and relative frequency of the input time-varying frequency periodic signal.Then the model of time and space difference step size and signal to noise ratio(SNR)and relative frequency of quantum random filter is established by least square method.Finally,the parameters of the quantum filter can be determined step by step by analyzing the characteristics of the actual signal.The simulation results of single-frequency signal and frequency time-varying signal show that the proposed method can quickly and accurately design the optimal filter parameters based on the characteristics of the input signal,and achieve significant filtering effects. 展开更多
关键词 quantum stochastic filter(QSF) parameters estimation least square(LS) short-time Fourier transform(STFT)
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Evaluation of Current Design Practices on Estimation of Axial Capacity of Concrete Encased Steel Composite Stub Columns: A Review
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作者 Amiya Kumar Samanta Amit Paul 《Journal of Civil Engineering and Architecture》 2013年第9期1080-1091,共12页
This paper presents the design assessment of concrete encased I-sections composite column based approaches given in Eurocode, ACI Code, BS Code and AISC-LRFD. This study includes comparison of various design parameter... This paper presents the design assessment of concrete encased I-sections composite column based approaches given in Eurocode, ACI Code, BS Code and AISC-LRFD. This study includes comparison of various design parameters and evaluation of design strength based on the procedures predicted in the various codes of practices. A practical example has been assumed and calculation has been shown to evaluate their potentiality in understanding in predicting the potentiality of various procedures. The obtained results based on the methods varies widely, because of the different design considerations adopted by the different codes. As such, they have hardly considered the effect of confinement of the concrete due to the presence of longitudinal reinforcements as well as lateral ties. The study has attempted to throw light on critical review and their potentiality in assessing the strength of such concrete encased composite column under purely axial loads. 展开更多
关键词 Concrete encased structural steel composite column design philosophy.
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Axial compressive behavior and design method of tubed circular steel reinforced concrete short columns
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作者 Jasim Ali Abdullah 张素梅 刘界鹏 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第1期1-7,共7页
To study the behavior and design of tubed circular steel reinforced concrete (TCSRC) short column under axial compressive loads, a nonlinear finite element model (FEM) has been developed to simulate this kind of struc... To study the behavior and design of tubed circular steel reinforced concrete (TCSRC) short column under axial compressive loads, a nonlinear finite element model (FEM) has been developed to simulate this kind of structure. Depending on the FEM results, an elastic-plastic analysis was carried out to clarify the status of steel tube, then a simplified procedure was proposed to predict the compressive axial load strength. The results obtained from this procedure were compared with the test results. It is found that they agree well each other. 展开更多
关键词 TCSRC short column FEM elastic-plastic analysis compressive axial load strength
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SMS-Parking Service Introduced in Oman
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作者 Syed Jafar Naqvi Hafedh AI-Shihi Saqib Ali 《Computer Technology and Application》 2011年第9期712-715,共4页
Mobile computing has increased quite rapidly over the past few years. The major drivers of mobile computing are large number of mobile phone users. As their number is increasing worldwide, different organizations are ... Mobile computing has increased quite rapidly over the past few years. The major drivers of mobile computing are large number of mobile phone users. As their number is increasing worldwide, different organizations are offering their services using the mobile devices. Oman is a developing country that strives to adapt M-services. The number of mobile phone users in Oman increased substantially since its launch in 1996. Prepaid mobile services and SMS (Short Message Services) were introduced in 2001 and both are currently popular with subscribers. Such fine appeal influenced many government organizations to go mobile with their services. This paper describes the SMS-Parking service, which is introduced recently by a joint venture of the Muscat Municipality and the Oman Mobile company offering mobile services to its citizens and reports the initial feedback of its users. This study shows that the new service is not yet popular among its users and may need their more positive attitudes toward it for its quick adoption. 展开更多
关键词 Mobile computing m-services short message services (SMS) SMS-parking service
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