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Generic Issues on Broad-Scale Soil Monitoring Schemes: A Review

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Pedosphere 2012年第4期22卷 456-469页

作者： D. ARROUAYS B. P. MARCHAnT n. P. A. SABY j. MEERSMAnS T. G. ORTOn M. P. MARTIn P. H. BELLAMY R. M. LARK M. KIBBLEWHITE InRA US 1106 InfoSol Unit CS 40001 Ardon F-45075 Orléans cedex 2 (France) Rothamsted Research Harpenden Hertfordshire AL5 2JQ (UK) Cranfield University Cranfield Bedfordshire MK43 0AL (UK) British Geological Survey Keyworth Nottingham NG12 5GG (UK)

numerous scientific challenges arise when designing a soil monitoring network (SMn), especially when assessing large areas and several properties that are driven by numerous controlling factors of various origins and scales. Different broad approaches to the establishment of SMns are distinguished. It is essential to establish an adequate sampling protocol that can be applied rigorously at each sampling location and time. We make recommendations regarding the within-site sampling of soil. Different statistical methods should be associated with the different types of sampling design. We review new statistical methods that account for different sources of uncertainty. Except for those parameters for which a consensus exists, the question of testing method harmonisation remains a very difficult issue. The establishment of benchmark sites devoted to harmonisation and inter-calibration is advocated as a technical solution. However, to our present knowledge, no study has addressed crucial scientific issues such as how many calibration sites are necessary and how to locate them.

关键词：土壤监测脊髓运动神经元展望统计方法抽样设计科学问题监测网络控制因素

Stress Analysis of Bolted joints Part II. Contact and Slip Analysis of a Four Bolt joint

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Modern Mechanical Engineering 2014年第1期4卷 46-55页

作者： László Molnár Károly Váradi jános Holubán Andor Tamási Department of Machine and Product Design Budapest University of Technology and Economics Budapest Hungary

For up-to-date bolted joints, first of all in vehicles, high strength bolts of 10.9 or even 12.9 are used, which are preloaded up to 90% or even 100% of the yield strength. The primary aim of this high degree utilization is the weight reduction. For the analytic dimensioning of bolted joints, the VDI 2230 Richtlinien German standard [1] provides support. However, the analytic model can mostly consider the true structural characteristics only in a limited way. The analytic modeling is especially uncertain in case of multiple bolted joints when the load distribution among the bolts depends reasonably upon the elastic deformation of the participating elements in the joints over the geometry of the bolted joint. The first part of this paper deals with the problems of numerical modeling and stress analysis, respectively specifying the analytic dimensioning procedure by applying elastic or rather elastic-plastic material law. The error magnitude in bolted joint calculation was examined in case of omitting the existing threaded connection—between the bolt and the nut—in order to simplify the model. The second part of the paper deals with the dimensioning of stands and cantilevers’ multi-bolt fixing problems, first of all, with the load distribution among the bolts keeping in view the analysis of the local slipping relations. For demonstrating the above technique, an elaborated numeric procedure is presented for a four-bolted cantilever, having bolted joints pre-tightened to the yield strength.

关键词： Bolted joints numerical Modeling Stress Analysis

A Long-Range Generalized Predictive Control Algorithm for a DFIG Based Wind Energy System

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IEEE/CAA journal of Automatica Sinica 2019年第5期6卷 1209-1219页

作者： j.S.Solis-Chaves Lucas L.Rodrigues C.M.Rocha-Osorio Alfeu j.Sguarezi Filho the Department of Energy Engineering at the Federal University of ABC-UFABC Santo AndreSPBrazil

This paper presents a new Long-range generalized predictive controller in the synchronous reference frame for a wind energy system doubly-fed induction generator based. This controller uses the state space equations that consider the rotor current and voltage as state and control variables, to execute the predictive control action. Therefore, the model of the plant must be transformed into two discrete transference functions, by means of an auto-regressive moving average model, in order to attain a discrete and decoupled controller, which makes it possible to treat it as two independent single-input single-output systems instead of a magnetic coupled multiple-input multiple-output system. For achieving that, a direct power control strategy is used, based on the past and future rotor currents and voltages estimation. The algorithm evaluates the rotor current predictors for a defined prediction horizon and computes the new rotor voltages that must be injected to controlling the stator active and reactive powers. To evaluate the controller performance, some simulations were made using Matlab/Simulink. Experimental tests were carried out with a small-scale prototype assuming normal operating conditions with constant and variable wind speed profiles. Finally, some conclusions respect to the dynamic performance of this new controller are summarized.

关键词： Direct power control doubly-fed induction generator flux oriented control generalized predictive control long-range predictive control wind energy systems

Physical simulation and application of a new TEM configuration

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Physical simulation and application of a new TEM configurati...

Crustal structure beneath Tien Shan orogenic belt and its adjacent regions from multi-scale seismic data

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： G.Q.Xue X.Li·H.j.Quan S.jaggar n.n.Zhou Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of Sciences College of Geology Engineering and Geomatics Chang'an University

In some applications,especially for tunnel surveys and ancient tomb investigations,the scale of survey location is so small that it is impossible to lay a large enough transmitter loop for detection.A small-scale and high-power Transient Electromagnetic(TEM) transmitter configuration must be adapted to detect longer distance or greater *** the TEM surveying configuration may facilitate improving signal penetration and precision of TEM *** on physical simulation,a newly designed special-loop-source TEM survey configuration has been introduced,which employs four square apertures within a single large transmitter loop to excite stronger *** primary and secondary fields have been measured using both the new special-loop system and standard normal single loop TEM configuration for different receiver-transmitter separations and for different target *** response curves were compared, revealing that the primary field intensity and the secondary field response were improved by the special-loop transmitter system as compared to the standard *** new special-loop configuration can be used for tunnel TEM prediction and other TEM investigations.A case study was conducted on tunnel forecasting in Hubei Province,China. This terra TEM survey showed that it is an effective and successful method for exploring and predicting challenging geological structures ahead of a tunnel wall during excavation.

关键词： Transient electromagnetic Loop configuration Small loop Model tests

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Science China Earth Sciences 2017年第10期60卷 1769-1782页

作者： n.Ghani KHAn BAI Ling ZHAO junMeng LI GuoHui M.Moklesur RAHMAn CHEnG Cheng YAnG jianYa Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau ResearchChinese Academy of Sciences Department of Earth Sciences COMSATS Institute of Information Technology (CIIT)

As one of the world's most active intracontinental mountain belts, Tien Shan has posed questions for researchers regarding the formation of different tectonic units and active shallow seismicity. Here, we used a huge data set comprising of 7094 earthquakes from local, regional and teleseismic seismic stations. We used waveform modeling and multi-scale double-difference earthquake relocation technique to better constrain the source parameters of the earthquakes. The new set of events provided us with better initial earthquake locations for further tomographic investigation. We found that reverse-faulting earthquakes dominate the whole study area while the fault plane solutions for earthquakes beneath the northwestern Tarim Basin and the Main Pamir Thrust are diverse. There is a low-velocity anomaly beneath Bashkaingdy at depth of 80 km, and high-velocity anomalies beneath central Tien Shan at shallower depths. These observations are the keys to understand the mechanism of Tien Shan's formation because of Tarim Basin northward and Kazakh Shield's southward subduction in the south and north respectively. Velocities beneath western Tien Shan are relatively high. We thus infer that the Western Tien Shan is relatively less deformed than the eastern Tien Shan primarily due to a relatively brittle mantle.

关键词：地震资料多尺度地壳结构塔里木盆地北部邻区 c带速度异常陆内造山带

Appearance of aseptic vascular grafts after endovascular aortic repair on[(18)F]fluorodeoxyglucose positron emission tomography/computed tomography

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世界放射学杂志:英文版(电子版) 2023年第8期15卷 241-249页

作者： Paige Bennett Maria Bernadette Tomas Christopher F Koch Kenneth j nichols Christopher j Palestro Department of Radiology LIJMC Northwell HealthNew Hyde ParkNY 11040United States Department of Radiology Zucker School of Medicine at Hofstra/NorthwellHempsteadNY 11549United States Division of nuclear Medicine and Molecular Imaging Department of RadiologyNorthwell HealthNew Hyde ParkNY 11040United States

BACKGROUnD Diagnosis of prosthetic vascular graft infection with[(18)F]fluorodeoxyglucose positron emission tomography/computed tomography(18F-FDG PET/CT)allows for early detection of functional changes associated with infection,based on increased glucose utilization by activated macrophages and *** vascular grafts,like all foreign bodies,can stimulate an inflammatory response,which can present as increased activity on 18F-FDG PET/***,distinguishing aseptic inflammation from graft infection,though important,can be *** the case of endovascular aneurysm repair(EVAR),a minimally invasive procedure involving the transfemoral insertion of an endoprosthetic stent graft,the normal postoperative appearance of these grafts on 18F-FDG PET/CT can vary over time,potentially confounding study *** To investigate the visual,semiquantitative,and temporal characteristics of aseptic vascular grafts in patients status post *** In this observational retrospective cohort study,patients with history of EVAR who underwent 18F-FDG PET/CT for indications other than infection were identified *** patients were asymptomatic for graft infection-no abdominal pain,fever of unknown origin,sepsis,or leukocytosis-at the time of imaging and for≥2 mo after each PET/*** studies such as CT for each patient were also reviewed,and any patients with suspected or confirmed vascular graft infection were *** hundred two scans performed on 43 patients(34 males;9 females;age=77±8 years at the time of the final PET/CT)were retrospectively *** 43 patients had an abdominal aortic(AA)vascular graft,40 patients had a right iliac(RI)limb graft,and 41 patients had a left iliac(LI)limb *** patients had 1 PET/CT and 21 patients had from 2 to 9 PET/*** were imaged between 2 mo to 168 mo(about 14 years)post *** grafts were imaged within 6 mo of placement,including three that were imaged wit

关键词： Aseptic vascular grafts Endovascular aortic repair [(18)F]fluorodeoxyglucose positron emission tomography/computed tomography

A Comparative in vitro Study on Biomedical Zr-2.5X(X=nb,Sn) Alloys

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journal of Materials Science & Technology 2014年第4期30卷 299-306页

作者： F.Y.Zhou K.j.Qiu D.Bian Y.F.Zheng j.P.Lin Centre for Biomedical Materials and Engineering Harbin Engineering University Department of Materials Science and Engineering College of EngineeringPeking University State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

nb and Sn are major alloying elements in Zr alloys. In this study, the microstructure, mechanical properties, corrosion behavior, cytocompatibility and magnetic resonance imaging （MRI） compatibility of Zr-2.5X （X = nb, Sn） alloys for biomedical application are comparatively investigated. It is found that Zr-2.5nb alloy has a duplex structure of ~ and ~ phase and Zr-2.5Sn alloy is composed of α phase. Both separate addition of nb and Sn can strengthen Zr but nb is more effective in strengthening Zr than Sn. The studied Zr-2.5X （X = nb, Sn） alloys show improved corrosion resistance compared to pure Zr as indicted by the decreased corrosion current density. The alloying addition of nb enhances the pitting resistance of Zr, whereas the addition of Sn decreases the pitting resistance of Zr. The extracts of Zr-2.5X alloys produce no significant deleterious effect on fibroblast cells （L-929） and osteoblast-Iike cells （MG 63）, indicating good in vitro cytocompatibility. The Zr-2.5X （X = nb, Sn） alloys show decreased magnetic susceptibility compared to pure Zr and their magnetic susceptibility is far lower than that of pure Ti and Ti-6AI-4V alloy. Based on these facts, Zr-2.5nb alloy is more suitable for implant material than Zr-2.5Sn alloy. Sn is not suitable as individual alloying addition for Zr because Sn addition decreases the pitting resistance in physiological solution.

关键词： Zr alloys Mechanical properties Corrosion resistance Cytocompatibility Magnetic susceptibility

高海拔下锌的高浸出率——谢里特为中国西部矿业公司进行的锌氧压浸出研究

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中国有色冶金 2009年第3期38卷 16-21页

作者： M.j.Collins R.j.Kalanchey I.M.Masters n.E.Tuffrey 杨征谢里特国际公司西部矿业股份有限公司青海西宁811600

西部矿业(WMC)甘河精炼厂海拔高,WMC矿山生产的精矿含铁高,这两点是WMC为其新的锌精炼厂选择氧压浸出工艺的关键因素。谢里特公司在萨斯喀彻温堡用WMC从中国青海省提供的精矿样品进行了氧压浸出试验,本论文描述了该试验的结果。小型间... 详细信息

西部矿业(WMC)甘河精炼厂海拔高,WMC矿山生产的精矿含铁高,这两点是WMC为其新的锌精炼厂选择氧压浸出工艺的关键因素。谢里特公司在萨斯喀彻温堡用WMC从中国青海省提供的精矿样品进行了氧压浸出试验,本论文描述了该试验的结果。小型间断氧压浸出试验和四天连续扩大试验的结果都进行了报告。连续扩大试验包括两段氧压浸出、中和及除铁的连续操作,产出无铁硫酸锌溶液。氧压浸出取得了大于98%的锌浸出率,同时产出含有约9 g/L硫酸和2 g/L铁的溶液。中和及除铁后,溶液约含170g/L锌和<10mg/L的铁。从锌精矿原料到元素硫副产品的总硫回收率约为85%,从中和渣中可回收原料中75～80%的铟。试验结果显示了谢里特锌氧压浸出工艺的技术和经济优势,并且为工程设计提供了所需数据。

关键词：氧压浸出高海拔高铁锌精矿高浸出率

Effect of 1Al addition on deformation behavior of Mg

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journal of Magnesium and Alloys 2021年第2期9卷 489-498页

作者： ji Hyun Hwang A.Zargaran Gyeongbae Park O.Lee B.-j.Lee nack j.Kim Center for Advanced Aerospace Materials Pohang University of Science and Technology(POSTECH)PohangSouth Korea

Deformation behavior of 1 Al containing Mg alloy has been investigated in the present *** annealing,the Mg-1 Al alloy shows a typical basal *** compared to the pure Mg having a similar texture and grain size,the Mg-1 Al alloy shows much higher strength and larger *** trace analyses of the tensile strained specimens show that non-basal slips such as pyramidal I and II slips can be easily activated at an early stage of deformation in the Mg-1 Al alloy and the grains in the Mg-1 Al alloy are seen to accommodate a larger degree of deformation than those in the pure Mg at a given *** increasing tensile strain,however,there is a strain localization along the initially formed slip lines of non-basal slips,forming surface steps without activating multiple slip lines.

关键词： Deformation behavior Slip trace analysis non-basal slip Strain localization Ductility