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Accounting for the uncertainties in the estimation of average shear wave velocity using – correlations

《结构与土木工程前沿（英文）》 2021年 第15卷 第5期   页码 1199-1208 doi: 10.1007/s11709-021-0749-1

摘要： Site-specific seismic hazard analysis is crucial for designing earthquake resistance structures, particularly in seismically active regions. Shear wave velocity ( V S) is a key parameter in such analysis, although the economy and other factors restrict its direct field measurement in many cases. Various V S–SPT– N correlations are routinely incorporated in seismic hazard analysis to estimate the value of V S. However, many uncertainties question the reliability of these estimated V S values. This paper comes up with a statistical approach to take care of such uncertainties involved in V S calculations. The measured SPT– N values from all the critical boreholes were converted into statistical parameters and passed through various correlations to estimate V S at different depths. The effect of different soil layers in the boreholes on the Vs estimation was also taken into account. Further, the average shear wave velocity of the top 30 m soil cover ( V S30) is estimated after accounting for various epistemic and aleatoric uncertainties. The scattering nature of the V S values estimated using different V S– N correlations was reduced significantly with the application of the methodology. Study results further clearly demonstrated the potential of the approach to eliminate various uncertainties involved in the estimation of V S30 using general and soil-specific correlations.

关键词： uncertainties     V S– N correlations     V S30     SPT data     statistical methodology    

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Exergy analysis and simulation of a 30MW cogeneration cycle

Nikhil Dev, Samsher, S. S. Kachhwaha, Rajesh Attri

《机械工程前沿（英文）》 2013年 第8卷 第2期   页码 169-180 doi: 10.1007/s11465-013-0263-9

摘要：

Cogeneration cycle is an efficient mean to recover the waste heat from the flue gases coming out of gas turbine. With the help of computer simulation, design parameters may be selected for the best performance of cogeneration cycle. In the present work a program is executed in software EES on the basis of mathematical modelling described in paper to study cogeneration cycle performance for different parameters. Results obtained are compared with the results available in literature and are found in good agreement with them. Real gas and water properties are inbuilt in the software. Results show that enthalpy of air entering the combustion chamber is higher than that of the flue gases at combustion chamber outlet. For different operative conditions, energy and exergy efficiencies follow similar trends; although, exergy efficiency values are always lower than the corresponding energy efficiency ones. From the results it is found that turbine outlet temperature (TIT) of 524°C is uniquely suited to efficient cogeneration cycle because it enables the transfer of heat from exhaust gas to the steam cycle to take place over a minimal temperature difference. This temperature range results in the maximum thermodynamic availability while operating with highest temperature and highest efficiency cogeneration cycle. Effect of cycle pressure ratio (CR), inlet air temperature (IAT) and water pressure at heat recovery steam generator (HRSG) inlet on the 30 MW cogeneration cycle is also studied.

关键词： Cogeneration cycle     air compressor     HRSG     gas turbine     regenerator     CR     IAT    

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我国地震预测成绩的回顾与统计

高建国

《中国工程科学》 2009年 第11卷 第6期   页码 129-131

摘要：

地震预测预报的难度大，但并非了无痕迹或不可知，我国每次较大的地震都有案例总结。统计表明，近４０ 年来，有７７ 次地震在发生前均有中期、短期甚至临震预测，不能因为汶川地震预测的失败，就全面抹杀中国的地震预报成绩，即我国的地震预测成绩是应予肯定的，汶川地震也并非是无前兆的“怪震”。

关键词： 地震     地震预测     中国近30 多年的地震预报统计    

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Effect of exhaust gas recirculation and ethyl hexyl nitrate additive on biodiesel fuelled diesel engine for the reduction of NO

S. R MURTHY, V. V. SUBBARAO, K. Vijaya KUMAR

《能源前沿（英文）》 2012年 第6卷 第3期   页码 304-310 doi: 10.1007/s11708-012-0195-9

摘要： Cetane improvers reduce the ignition delay, which in turn reduces the combustion temperatures thereby reduce NO emissions. Exhaust gas recirculation (EGR) proved to be an effective way to reduce the NO emissions. In this present experimental work, a combination of exhaust gas recirculation and cetane improver ethyl hexyl nitrate (EHN) is used to investigate the performance and exhaust emissions of a single cylinder four stroke naturally aspirated direct injection and air cooled diesel engine. Test results show that the brake thermal efficiency increases with the increase in the percentage of EGR which is accompanied by a reduction in brake specific fuel consumption and exhaust gas temperatures, and that bio-diesel with cetane improver under 20% EGR reduces NO emissions by 33% when compared to baseline fuel without EGR. However carbon monoxide (CO), hydro carbon (HC) and smoke emissions increase with an increase in percentage of EGR.

关键词： additive     exhaust gas recirculation (EGR)     emissions     ethyl hexyl nitrate (EHN)     performance    

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Statistical modeling of radiolytic (

S. Muthu Iswarya, B. Nirkayani, A. Kavithakani, V. C. Padmanaban

《环境科学与工程前沿（英文）》 2019年 第13卷 第3期 doi: 10.1007/s11783-019-1126-3

摘要：

Linear, interactive and quadratic effects of process parameters were studied.

Degradation of Ofloxacin (Ofx) was related with G value of irradiation process.

The synergistic effect of H2O2 on lower dose of g-irradiation was established.

The process follows pseudo first order with dose constant (d = 0.232 kGy–1).

关键词： Ofloxacin     Gamma irradiation     Face centered central composite design     Reaction kinetics     Gas Chromatography-Mass spectrum    

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Epidemiological studies of women under age 30 infected with human papillomavirus

Zhihua LIU MD, Qing LI BM, Weihong LI BM,

《医学前沿（英文）》 2009年 第3卷 第4期   页码 459-462 doi: 10.1007/s11684-009-0084-8

摘要： The aim of this paper was to investigate the prevalence of human papilloma virus (HPV) infection in women under 30 years old with cervical intraepithelial neoplasia (CIN) or cervical cancer, in order to provide a basis for cervical cancer prevention and treatment. We recruited 2052 female cases from the education system in Futian District, Shenzhen city, from April 2006 to April 2008, with age ranging from 22 to 60 years old. Second-generation hybrid capture test was done for detection of female genital tract HPV and cervical colposcopy for screening CIN or cervical cancer. The prevalence of HPV and cervical precancerous lesions or cervical cancer was evaluated in different age groups of women. The HPV positive rate was 247/2052 (12.00%), and 35/2052 (1.71%) of the cases were≥CIN I by pathological diagnosis. In the 22―29-year-old age group, there were 291 cases, including 39HPV-positive cases (13.40%) and one case of pathological diagnosis≥CIN I (0.34%), and there were 1761 cases in the 30―60-year-old age group, including 208 HPV-positive cases (11.81%) and 34 cases of pathological diagnosis≥CIN I (1.93%). The HPV-positive rate of 22―29-year-old age group was higher than that of 30―60-year-old age group, but the difference was not significant ( = 0.5967, = 0.4398); the CIN and cervical cancer detection rate of the former group was lower than that of the latter one, and the difference was not significant either ( = 3.7519, = 0.0527). The cases in 30―60-year-old age group were divided into five age sub-groups, and the HPV-positive rate of the 22―29-year-old age group was compared with the remaining groups, and it was found that the HPV-positive rate of the former group (13.40%) was lower than that of the 40―44-year-old age group (14.70%) but higher than that of the other four groups. Moreover, the difference in the HPV-positive rate between the 22―29-year-old age group and the 50―60-year-old age group (6.06%) was significant ( = 5.545, = 0.018), but the difference between the 22― 29-year-old age group and each of the other four groups was not significant (>0.05). In addition, the CIN and cervical cancer detection rate of the 22―29-year-old age group (0.34%) was lower than that of the remaining five groups, and the difference between the 22―29-year-old age group and the 35―39-year-old age group (2.26%), and between 22―29-year-old age group and 40―44-year-old age group (2.30%) was significant ( = 4.446, = 0.0035; = 4.525, = 0.0363, respectively), but the difference between the 22―29-year-old age group and each of other three groups was not significant (>0.05). Furthermore, 80.00% (28/35) cases of pathological diagnosis≥CIN I and 90.91% (10/11) lesions of pathological diagnosis≥CIN II occurred at 35―49 years of age. For many young women below the age of 30 who were infected with high-risk HPV were one-off infections, so it was not appropriate to recommend HPV detection as cervical precancerous lesions or cancer screening program for women less than 30 years old. The prevention and treatment of cervical cancer should be focused on those women more than 35 years of age.

关键词： cervical cancer     human papilloma virus     cervical intraepithelial neoplasia    

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Perioperative management for parturients with pulmonary hypertension: experience with 30 consecutive

null

《医学前沿（英文）》 2013年 第7卷 第3期   页码 395-395 doi: 10.1007/s11684-013-0289-8

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Fatigue crack growth simulations of 3-D linear elastic cracks under thermal load by XFEM

Himanshu PATHAK,Akhilendra SINGH,I.V. SINGH,S. K. YADAV

《结构与土木工程前沿（英文）》 2015年 第9卷 第4期   页码 359-382 doi: 10.1007/s11709-015-0304-z

摘要： This paper deals with the fatigue crack growth simulations of three-dimensional linear elastic cracks by XFEM under cyclic thermal load. Both temperature and displacement approximations are extrinsically enriched by Heaviside and crack front enrichment functions. Crack growth is modelled by successive linear extensions, and the end points of these linear extensions are joined by cubic spline segments to obtain a modified crack front. Different crack geometries such as planer, non-planer and arbitrary spline shape cracks are simulated under thermal shock, adiabatic and isothermal loads to reveal the sturdiness and versatility of the XFEM approach.

关键词： 3-D cracks     fatigue life     Paris law     thermal load     XFEM    

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Response in piled raft foundation of tall chimneys under along-wind load incorporating flexibility of soil

JAYALEKSHMI,S.V. JISHA,R. SHIVASHANKAR

《结构与土木工程前沿（英文）》 2015年 第9卷 第3期   页码 307-322 doi: 10.1007/s11709-015-0288-8

摘要： The present paper deals with the numerical analysis of tall reinforced concrete chimneys with piled raft foundation subjected to along-wind loads considering the flexibility of soil. The analysis was carried out using finite element method on the basis of direct method of soil-structure interaction (SSI). The linear elastic material behavior was assumed for chimney, piled raft and soil. Four different material properties of soil stratum were selected in order to study the effect of SSI. The chimney elevation and the thickness of raft of piled raft foundation were also varied for the parametric study. The chimneys were assumed to be located in terrain category 2 and subjected to a maximum wind speed of 50 m/s as per IS:875 (Part 3)-1987. The along-wind loads were computed according to IS:4998 (Part 1)-1992. The base moments of chimney evaluated from the SSI analysis were compared with those obtained as per IS:4998 (Part 1)-1992. The tangential and radial bending moments of raft of piled raft foundation were evaluated through SSI analysis and compared with those obtained from conventional analysis as per IS:11089-1984, assuming rigidity at the base of the raft foundation. The settlements of raft of piled raft foundation, deflection of pile and moments of the pile due to interaction with different soil stratum were also evaluated. From the analysis, considerable reduction in the base moment of chimney due to the effect of SSI is observed. Higher radial moments and lower tangential moments were obtained for lower elevation chimneys with piled raft resting on loose sand when compared with conventional analysis results. The effect of SSI in the response of the pile is more significant when the structure-foundation system interacts with loose sand.

关键词： finite element method     piled raft     tall chimney     soil-structure interaction     along-wind load    

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Fault diagnosis of spur gearbox based on random forest and wavelet packet decomposition

Diego CABRERA,Fernando SANCHO,René-Vinicio SÁNCHEZ,Grover ZURITA,Mariela CERRADA,Chuan LI,Rafael E.VÁSQUEZ

《机械工程前沿（英文）》 2015年 第10卷 第3期   页码 277-286 doi: 10.1007/s11465-015-0348-8

摘要：

This paper addresses the development of a random forest classifier for the multi-class fault diagnosis in spur gearboxes. The vibration signal’s condition parameters are first extracted by applying the wavelet packet decomposition with multiple mother wavelets, and the coefficients’ energy content for terminal nodes is used as the input feature for the classification problem. Then, a study through the parameters’ space to find the best values for the number of trees and the number of random features is performed. In this way, the best set of mother wavelets for the application is identified and the best features are selected through the internal ranking of the random forest classifier. The results show that the proposed method reached 98.68% in classification accuracy, and high efficiency and robustness in the models.

关键词： fault diagnosis     spur gearbox     wavelet packet decomposition     random forest    

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Elasto-plastic fatigue crack growth analysis of plane problems in the presence of flaws using XFEM

S. SHEDBALE,I. V. SINGH,B. K. MISHRA

《结构与土木工程前沿（英文）》 2015年 第9卷 第4期   页码 420-440 doi: 10.1007/s11709-015-0305-y

摘要： In this paper, elasto-plastic XFEM simulations have been performed to evaluate the fatigue life of plane crack problems in the presence of various defects. The stress-strain response of the material is modeled by Ramberg-Osgood equation. The von-Mises failure criterion has been used with isotropic hardening. The -integral for two fracture modes (mode-I and mode-II) is obtained by decomposing the displacement and stress fields into their symmetric and antisymmetric parts, then individual stress intensity factors are extracted from -integral. The fatigue life obtained by EPFM is found quite close to that obtained by LEFM.

关键词： XFEM     von-Mises yield criterion     isotropic hardening     fatigue crack growth     J-integral    

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简评深部采矿的机遇与挑战

,Zhao Jian,Ju Minghe,De Silva Radhika V. S.,Rathnaweera Tharaka D.,Bandara Adheesha K. M. S.

《工程（英文）》 2017年 第3卷 第4期   页码 546-551 doi: 10.1016/J.ENG.2017.04.024

摘要：

随着全球生活水平的提高，更多消费者进入了矿物资源市场，使得矿物资源的消耗正在迅速增长。其结果是，在21 世纪为了有效应对矿物资源供应危机，地下采矿持续地向更深的水平推进。然而，深部采矿在一个需要有非常规技术以及有挑战性的环境下进行，为了克服这些挑战和实现可观的经济收益需要重大的创新性解决方案、最佳实践以及实施额外的安全标准。这些挑战包括深部采矿工程常常遇到的灾难性事件：岩爆、瓦斯突出、高的原岩和次生应力、大变形、挤压和流变岩体以及高温。本文回顾了全球深部采矿现状，指出了一些与深部采矿的岩石力学和工程地质相关的技术进展及机遇。在这些技术进展中，基于全自动化的采矿和矿物提取过程的无人工作面和无人矿山已成为21 世纪的重要领域。

关键词： 深部采矿     岩石力学     岩爆     原岩应力     采矿自动化    

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Spatial targeting evaluation of energy and environmental performance of waste-to-energy processing

Petar S. Varbanov, Timothy G. Walmsley, Yee V. Fan, Jiří J. Klemeš, Simon J. Perry

《化学科学与工程前沿（英文）》 2018年 第12卷 第4期   页码 731-744 doi: 10.1007/s11705-018-1772-1

摘要：

Waste-to-energy supply chains are important potential contributors to minimising the environmental impacts of municipal solid waste by reducing the amounts of waste sent to landfill, as well as the fossil fuel consumption and environmental footprints. Accounting for the spatial and transport properties of the waste-to-energy supply chains is crucial for understanding the problem and improving the supply chain designs. The most significant challenge is the distributed nature of the waste generation and the household energy demands. The current work proposes concepts and a procedure for targeting the size of the municipal solid waste collection zone as the first step in the waste-to-energy supply chains synthesis. The formulated concepts and the provided case study reveal trends of reducing the net greenhouse gas savings and energy recovery by increasing the collection zone size. Population density has a positive correlation with the greenhouse gas saving and energy recovery performance. For smaller zone size the energy recovery from waste approaches and in some cases may surpass the energy spent on waste transportation. The energy recovery and greenhouse gas savings remain significant even for collection zones as large as 200 km2. The obtained trends are discussed and key directions for future work are proposed.

关键词： waste-to-energy     supply chain optimisation     GHG savings     energy recovery ratio    

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Controlled drug delivery systems: the next 30 years

Yeonhee YUN,Byung Kook LEE,Kinam PARK

《化学科学与工程前沿（英文）》 2014年 第8卷 第3期   页码 276-279 doi: 10.1007/s11705-014-1426-x

摘要： The drug delivery scientists need to reexamine the advances made during the past 60 years, analyze our current abilities, and design the future technologies that will propel us to achieve the next level of drug delivery technologies. History shows that the first generation (1G) of drug delivery research during 1950–1980 was quite productive, while the second generation (2G) technologies developed during 1980–2010 were not as prolific. The ultimate goal of drug delivery research is to develop clinically useful formulations to treat various diseases. Effective drug delivery systems can be developed by overcoming formulation barriers and/or biological barriers. The engineering approach has a limit in solving the problem, if biological difficulties are not clearly identified and understood. The third generation (3G) drug delivery systems will have to focus on understanding the biological barriers so that they can be overcome by engineering manipulation of the drug delivery systems. Advances in the next 30 years will be most accelerated by starting open dialogues without any preconceived ideas on drug delivery technologies. The new generation of drug delivery scientists needs to be aware of the successes and limitations of the existing technologies to design the new technologies for meaningful advances in the future.

关键词： drug delivery     history     formulation barriers     nanotechnology     clinical product    

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Characterization and seasonal distribution of microplastics in the nearshore sediments of the south-east coast of India, Bay of Bengal

Sambandam , S. K. Sivadas , T.V. Ramana Murthy

《环境科学与工程前沿（英文）》 2022年 第16卷 第1期   页码 10-10 doi: 10.1007/s11783-021-1444-0

摘要：

In view of increasing Microplastics (MPs) contamination in the marine environment and dearth of baseline data, a study was conducted on the abundance, characterization, and seasonal distribution of MPs in the nearshore sediments of the south-east coast of India. Sediment samples (n = 130) were collected at a distance of 1 km and 10 km from the shore region at varying depths (8–45 m) along the Chennai to Puducherry coast (165 km stretch), representing two seasons, i.e., south-west (July 2019 and July 2020) and north-east (January 2020) monsoons. The average abundance of MPs at the 22 offshore sites along the Chennai to Puducherry coast varied from 9±4.3 to 19±12.9 particles/50 g dry weight, in July 2019 and January 2020, respectively. July 2020 had an average abundance of 10±4.5 particles/50 g dry weight. Spatially, high levels of MPs were found at 1km stations and transects in proximity to the river inlets, and temporally, the north-east month recorded the maximum concentration. The dominant morphotype was the filament, and the major polymers were polyethylene and polypropylene. Scanning Electron Microscope (SEM) images revealed the surface irregularity and degradation of MPs due to weathering. The study highlights that high sediment contamination by MPs occurs during heavy rainfall and accumulates closer to river inlets. Eventually, this study suggests that appropriate management of plastic wastes on the landside will reduce MP contamination in the marine environment.

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标题 作者 时间 类型 操作

Accounting for the uncertainties in the estimation of average shear wave velocity using – correlations

期刊论文

Exergy analysis and simulation of a 30MW cogeneration cycle

Nikhil Dev, Samsher, S. S. Kachhwaha, Rajesh Attri

期刊论文

我国地震预测成绩的回顾与统计

高建国

期刊论文

Effect of exhaust gas recirculation and ethyl hexyl nitrate additive on biodiesel fuelled diesel engine for the reduction of NO

S. R MURTHY, V. V. SUBBARAO, K. Vijaya KUMAR

期刊论文

Statistical modeling of radiolytic (

S. Muthu Iswarya, B. Nirkayani, A. Kavithakani, V. C. Padmanaban

期刊论文

Epidemiological studies of women under age 30 infected with human papillomavirus

Zhihua LIU MD, Qing LI BM, Weihong LI BM,

期刊论文

Perioperative management for parturients with pulmonary hypertension: experience with 30 consecutive

null

期刊论文

Fatigue crack growth simulations of 3-D linear elastic cracks under thermal load by XFEM

Himanshu PATHAK,Akhilendra SINGH,I.V. SINGH,S. K. YADAV

期刊论文

Response in piled raft foundation of tall chimneys under along-wind load incorporating flexibility of soil

JAYALEKSHMI,S.V. JISHA,R. SHIVASHANKAR

期刊论文

Fault diagnosis of spur gearbox based on random forest and wavelet packet decomposition

Diego CABRERA,Fernando SANCHO,René-Vinicio SÁNCHEZ,Grover ZURITA,Mariela CERRADA,Chuan LI,Rafael E.VÁSQUEZ

期刊论文

Elasto-plastic fatigue crack growth analysis of plane problems in the presence of flaws using XFEM

S. SHEDBALE,I. V. SINGH,B. K. MISHRA

期刊论文

简评深部采矿的机遇与挑战

,Zhao Jian,Ju Minghe,De Silva Radhika V. S.,Rathnaweera Tharaka D.,Bandara Adheesha K. M. S.

期刊论文

Spatial targeting evaluation of energy and environmental performance of waste-to-energy processing

Petar S. Varbanov, Timothy G. Walmsley, Yee V. Fan, Jiří J. Klemeš, Simon J. Perry

期刊论文

Controlled drug delivery systems: the next 30 years

Yeonhee YUN,Byung Kook LEE,Kinam PARK

期刊论文

Characterization and seasonal distribution of microplastics in the nearshore sediments of the south-east coast of India, Bay of Bengal

Sambandam , S. K. Sivadas , T.V. Ramana Murthy

期刊论文