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The Paris 2024 Olympic and Paralympic Games
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作者 Walter Herzog 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第6期717-718,共2页
The first modern Olympic Games took place in Athens in 1896.While in those early days of the Olympics only amateur and gentleman athletes were allowed to participate,today Olympic athletes are highly trained professio... The first modern Olympic Games took place in Athens in 1896.While in those early days of the Olympics only amateur and gentleman athletes were allowed to participate,today Olympic athletes are highly trained professionals often dedicating decades of preparation for the chance to compete in the Olympic Games.In sharp contrast to these highly trained athletes,the world’s population becomes less physically active on average,resulting in an obesity epidemic with associated metabolic syndrome and increased mortality through non-communicable diseases(e.g.,Collins et al.^(1)). 展开更多
关键词 OLYMPIC allowed SHARP
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Heteronuclear Magnetisms with Ultracold Spinor Bosonic Gases in Optical Lattices
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作者 Yongqiang Li Chengkun Xing +2 位作者 Ming Gong Guangcan Guo Jianmin Yuan 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第2期69-82,共14页
Motivated by recent realizations of spin-1 NaRb mixtures in the experiments[Phys.Rev.Lett.114,255301(2015);Phys.Rev.Lett.128,223201(2022)],we investigate heteronuclear magnetism in the Mott-insulating regime.Different... Motivated by recent realizations of spin-1 NaRb mixtures in the experiments[Phys.Rev.Lett.114,255301(2015);Phys.Rev.Lett.128,223201(2022)],we investigate heteronuclear magnetism in the Mott-insulating regime.Different from the identical mixtures where the boson statistics only admits even parity states from angular momentum composition,for heteronuclear atoms in principle all angular momentum states are allowed,which can give rise to new magnetic phases.While various magnetic phases can be developed over these degenerate spaces,the concrete symmetry breaking phases depend on not only the degree of degeneracy but also the competitions from many-body interactions.We unveil these rich phases using the bosonic dynamical mean-field theory approach.These phases are characterized by various orders,including spontaneous magnetization order,spin magnitude order,singlet pairing order,and nematic order,which may coexist specially in the regime with odd parity.Finally we address the possible parameter regimes for observing these spin-ordered Mott phases. 展开更多
关键词 PARITY MOMENTUM allowed
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Application of Sigma Metric Analysis to Evaluate the Performance of the Biochemistry Analytical System in a Medical Biology Laboratory in Côte d’Ivoire
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作者 Koffi Akissi Joelle Kouakou Francisk +3 位作者 Kouadio Charlotte Yeo Karna Ahiboh Hugues Hauhouot-Attoungbré Marie-Laure 《Journal of Analytical Sciences, Methods and Instrumentation》 2024年第1期14-21,共8页
Introduction: The Six Sigma methodology is an opportunity for a better understanding of the performance of analytical methods and for a better adaptation of the quality control management policy of the medical biology... Introduction: The Six Sigma methodology is an opportunity for a better understanding of the performance of analytical methods and for a better adaptation of the quality control management policy of the medical biology laboratory. Using the sigma metric, this study assessed the performance of the Biochemistry analytical system of a medical biology laboratory in Côte d'Ivoire. Methods: Six Sigma methodology was applied to 3 analytes (alanine aminotransferase, glucose and creatinine). Performance indicators such as measurement imprecision and bias were determined based on the results of internal and external quality controls. The sigma number was calculated using the total allowable error values proposed by Ricos et al. Results: For both control levels, ALT had a sigma number greater than 6 (7.6 for normal control and 7.9 for pathological control). However, low sigma numbers, less than or equal to 2 for creatinine (1.4 for normal control and 2 for pathological control) and less than 1 for glucose were found. Conclusion: This study revealed good analytical performance of ALT from the point of view of 6 sigma analysis. However, modifications to the overall quality control procedure for glucose and creatinine are needed to improve their analytical performance. The study should be extended to the entire laboratory’s analytes in order to modify the strategies of quality control procedures based on metric analysis for an overall improvement in analytical performance. 展开更多
关键词 Six Sigma Qualities Controls BIAS IMPRECISION Total Allowable Error
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不同材质管道定向钻穿越过程最大允许长度探讨 被引量:1
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作者 刘沛 《内蒙古石油化工》 CAS 2023年第7期56-59,共4页
在天然气管道定向钻过程中,不同材质管道所承受的拖拉力不尽相同,导致不同材质的管道最大回拖允许长度不同,本文通过分析钢质管材和聚乙烯管材定向钻穿越过程中的最大允许拖拉力、从而确定不同管材的最大回拖允许长度,为工程实际运用提... 在天然气管道定向钻过程中,不同材质管道所承受的拖拉力不尽相同,导致不同材质的管道最大回拖允许长度不同,本文通过分析钢质管材和聚乙烯管材定向钻穿越过程中的最大允许拖拉力、从而确定不同管材的最大回拖允许长度,为工程实际运用提供理论支持。 展开更多
关键词 Allowable length Different materials
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Research Progress of Genomes of Insect Pests in Paddy Field
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作者 XU Hongxing ZHAO Xianxin +1 位作者 LÜZhongxian LI Fei 《Rice science》 SCIE CSCD 2023年第5期369-373,共5页
Innovations in sequencing technology and the development of bioinformatics have allowed for studies of the genomics of many rice pests.At present,draft genomes of rice pests including Nilaparvata lugens,Sogatella furc... Innovations in sequencing technology and the development of bioinformatics have allowed for studies of the genomics of many rice pests.At present,draft genomes of rice pests including Nilaparvata lugens,Sogatella furcifera,Laodelphax striatellus,Sesamia inferens,Chilo suppressalis,Scirpophaga incertulas. 展开更多
关键词 PESTS CHILO allowed
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Dark Contributions to h→μ^(+)μ^(-) in the Presence of a μ-Flavored Vector-Like Lepton
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作者 Bibhabasu De 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第4期91-94,共4页
A simple extension of the standard model(SM) with a μ-flavored vector-like lepton(VLL) doublet and a real singlet scalar can have an interesting implication to the h→μ^(+)μ^(-)decay while offering the simplest pos... A simple extension of the standard model(SM) with a μ-flavored vector-like lepton(VLL) doublet and a real singlet scalar can have an interesting implication to the h→μ^(+)μ^(-)decay while offering the simplest possible explanation for the dark matter(DM) phenomenology.Assuming the real singlet scalar to be a viable DM candidate,it has been shown that the muon Yukawa coupling can have a negative contribution at the oneloop order if the 2^(nd) generation SM leptons are allowed to couple with the VLL doublet.The stringent direct detection bounds corresponding to a real singlet scalar DM can easily be relaxed if the SM quark sector was augmented with a dimension-6 operator at some new physics(NP) scale Λ_(NP).Thus,this model presents a significant phenomenological study where the muon Yukawa coupling can be corrected within a real singlet scalar DM framework.The considered parameter space can be tested/constrained through the high luminosity run of the LHC(HL-LHC) and future direct detection experiments. 展开更多
关键词 SCALAR SINGLET allowed
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Characterization of hot electrons generated by laser-plasma interaction at shock ignition intensities
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作者 E.D.Filippov M.Khan +17 位作者 A.Tentori P.Gajdos A.S.Martynenko R.Dudzak P.Koester G.Zeraouli D.Mancelli F.Baffigi L.A.Gizzi S.A.Pikuz Ph.D.Nicolaï N.C.Woolsey R.Fedosejevs M.Krus L.Juha D.Batani O.Renner G.Cristoforetti 《Matter and Radiation at Extremes》 SCIE EI CSCD 2023年第6期74-89,共16页
In an experiment carried out at the Prague Asterix Laser System at laser intensities relevant to shock ignition conditions(I>10^(16) W/cm^(2)),the heating and transport of hot electrons were studied by using severa... In an experiment carried out at the Prague Asterix Laser System at laser intensities relevant to shock ignition conditions(I>10^(16) W/cm^(2)),the heating and transport of hot electrons were studied by using several complementary diagnostics,i.e.,K_(α)time-resolved imaging,hard x-ray filtering(a bremsstrahlung cannon),and electron spectroscopy.Ablators with differing composition from low Z(parylene N)to high Z(nickel)were used in multilayer planar targets to produce plasmas with different coronal temperature and collisionality and modify the conditions of hot-electron generation.The variety of available diagnostics allowed full characterization of the population of hot electrons,retrieving their conversion efficiency,time generation and duration,temperature,and angular divergence.The obtained results are shown to be consistent with those from detailed simulations and similar inertial confinement fusion experiments.Based on the measured data,the advantages,reliability,and complementarity of the experimental diagnostics are discussed. 展开更多
关键词 SPECTROSCOPY shock allowed
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Allowance Extraction Considering of Inner and Outer Contour and Experimental Research on Belt Grinding of Hollow Blade
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作者 Yun Huang Ming Wei +2 位作者 Guijian Xiao Shuai Liu Yuan Wu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第3期230-240,共11页
Aero-engine fan blades of ten use a cavity structure to improve the thrust-to-weight ratio of the aircraft.However,the use of the cavity structure brings a series of difficulties to the manufacturing and processing of... Aero-engine fan blades of ten use a cavity structure to improve the thrust-to-weight ratio of the aircraft.However,the use of the cavity structure brings a series of difficulties to the manufacturing and processing of the blades.Due to the limitation of blade manufacturing technology,it is difficult for the internal cavity structure to achieve the designed contour shape,so the blade has uneven wall thickness and poor consistency,which affects the fatigue performance and airflow dynamic performance of the blade.In order to reduce the influence of uneven wall thickness,this paper proposes a grinding allowance extraction method considering the double dimension constraints(DDC)of the inner and outer contours of the hollow blade.Constrain the two dimensions of the inner and outer contours of the hollow blade.On the premise of satisfying the outer contour constraints,the machining model of the blade is modified according to the distribution of the inwall contour to obtain a more reasonable distribution of the grinding allowance.On the premise of satisfying the contour constraints,according to the distribution of the inwall contour,the machining model of the blade is modified to obtain a more reasonable distribution of the grinding allowance.Through the grinding experiment of the hollow blade,the surface roughness is below Ra0.4μm,and the contour accuracy is between-0.05~0.14 mm,which meets the processing requirements.Compared with the allowance extraction method that only considers the contour,the problem of poor wall thickness consistency can be effectively improved.It can be used to extract the allowance of aero-engine blades with hollow features,which lays a foundation for the study of hollow blade grinding methods with high service performance. 展开更多
关键词 Double dimension constraints Allowance extraction Abrasive belt grinding
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Optimal reduction and equilibrium carbon allowance price for the thermal power industry under China’s peak carbon emissions target
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作者 Jiaojiao Sun Feng Dong 《Financial Innovation》 2023年第1期344-370,共27页
As the largest source of carbon emissions in China,the thermal power industry is the only emission-controlled industry in the first national carbon market compliance cycle.Its conversion to clean-energy generation tec... As the largest source of carbon emissions in China,the thermal power industry is the only emission-controlled industry in the first national carbon market compliance cycle.Its conversion to clean-energy generation technologies is also an important means of reducing CO_(2)emissions and achieving the carbon peak and carbon neutral commitments.This study used fractional Brownian motion to describe the energy-switching cost and constructed a stochastic optimization model on carbon allowance(CA)trading volume and emission-reduction strategy during compliance period with the Hurst exponent and volatility coefficient in the model estimated.We defined the optimal compliance cost of thermal power enterprises as the form of the unique solution of the Hamilton–Jacobi–Bellman equation by combining the dynamic optimization principle and the fractional It?’s formula.In this manner,we obtained the models for optimal emission reduction and equilibrium CA price.Our numerical analysis revealed that,within a compliance period of 2021–2030,the optimal reductions and desired equilibrium prices of CAs changed concurrently,with an increasing trend annually in different peak-year scenarios.Furthermore,sensitivity analysis revealed that the energy price indirectly affected the equilibrium CA price by influencing the Hurst exponent,the depreciation rate positively impacted the CA price,and increasing the initial CA reduced the optimal reduction and the CA price.Our findings can be used to develop optimal emission-reduction strategies for thermal power enterprises and carbon pricing in the carbon market. 展开更多
关键词 Carbon peak Fractional Brownian motion Optimal control Carbon allowance price
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Impact of Multi-Axle Vehicles and Road Overloads on the Durability of Asphalt Pavements
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作者 Kokoro Kobori Doua Allain Gnabahou +1 位作者 Kossi Imbga Alphonse Sibri Sandwidi 《Open Journal of Civil Engineering》 2023年第2期237-251,共15页
The multiplication of heavy vehicle axles and road overloads are phenomena that are becoming increasingly important on the road network of the WAEMU community. These phenomena, although framed by standards, have an im... The multiplication of heavy vehicle axles and road overloads are phenomena that are becoming increasingly important on the road network of the WAEMU community. These phenomena, although framed by standards, have an impact on the durability of pavements. In this manuscript it is a question of evaluating the life of the road under the effect of traffic of these multi-axle vehicles and the different tolerances of overloads observed on the road network. To achieve this, a modeling of a bituminous pavement was made with the software ALIZE Lcpc Version 231 based on the principle of the French method of sizing. An inventory of multi-axle heavy goods vehicles was also made on a road with a weighing station. This traffic counting made it possible to classify heavy goods vehicles into three categories, namely: 1) trucks, 2) dual-wheeled semi-trailers and 3) single-wheeled semi-trailers. The results obtained show that in terms of aggressiveness, single-wheeled semi-trailers are the most aggressive, followed by heavy goods vehicles in the category of trucks with more than five axles and semi-trailers with dual wheels with more than seven axles. The durability of the road depends on the aggressiveness of heavy goods vehicles, it was found that the tolerance threshold for overloads of 15% of the total permissible rolling weight (TARW) or the total permissible laden weight (TALW) currently granted in the Community area needs to be reviewed. For durable road surfaces, this tolerance may only be allowed for heavy goods vehicles of type P11, P12 and P13. The 5% tolerance can be applied to all vehicles except heavy goods vehicles with single wheels. 展开更多
关键词 AGGRESSIVENESS Multi-Axle TARW TALW Allowable Deformation Modeling
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Media Watch
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《ChinAfrica》 2023年第11期7-7,共1页
EXCERPTS FROM MAJOR CHINESE MAGAZINES THE WANDERING POET Sanlian Lifeweek 2 October The immense box office success of Chang’An,a Chinese animated film released this summer,has allowed many people to rediscover Li Bai... EXCERPTS FROM MAJOR CHINESE MAGAZINES THE WANDERING POET Sanlian Lifeweek 2 October The immense box office success of Chang’An,a Chinese animated film released this summer,has allowed many people to rediscover Li Bai,a Tang Dynasty(618-907)poet who rivals his contemporary Du Fu for the title of China’s greatest poet of all time.A romantic in his view of life and also in his verse,Li is much loved for both his wildly imaginative poems and his carefree lifestyle.The poet was always on the move. 展开更多
关键词 allowed CONTEMPORARY IMMENSE
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电大英语第三册模拟试题(英文)
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作者 李士芗 《电大理工》 1994年第Z4期27-29,7,共4页
关键词 模拟试题 intended CAREFUL FOOTBALL 参考答案 allowed party VILLAGE 召刀 CHAIR
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invisible hand 小议
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作者 符延军 《语言教育》 2001年第3期21-21,共1页
invisible hand 是由英国人亚当·斯密(Adam Smith)首先提出来的。Adam Smith(1723—1790)是英国苏格兰人,经济学家与哲学家。他于1776年完成了经济学史上的经典著作《国富论》(The Wealth of Na-
关键词 经济学史 苏格兰人 国富论 WEALTH INVISIBLE hand 英语表达 看不见的手 经济学体系 西方政治 allowed
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语料库词典学的最新发展和未来趋势(下)——语料库数据在学习词典中的显性应用 被引量:5
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作者 Michael Rundell 夏立新(译) 朱冬生(译) 《辞书研究》 CSSCI 北大核心 2009年第4期81-91,共11页
关键词 学习词典 语料库 应用 显性 词典学 词典使用者 ALLOW 发展趋势
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2014年12月大学英语四级作文试题评析(二)
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作者 贾从永 《大学英语》 2015年第6期61-62,共2页
Directions:For this part,you are allowed 30 minutes to write a short essay about a campus activity that has benefited you most.You should state the reasons and write at least120 but no more than 180 words.这道作文题... Directions:For this part,you are allowed 30 minutes to write a short essay about a campus activity that has benefited you most.You should state the reasons and write at least120 but no more than 180 words.这道作文题目看似不难,但笔者在阅卷中却发现有将近一半的考生写偏题或跑题。先让我们一起仔细审审题:a campus activity that has benefited you most。 展开更多
关键词 大学英语四级 CAMPUS write minutes ESSAY PRONUNCIATION 校园活动 REASONS allowed MAINTAIN
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关于一次应力的余量加到二次应力计算中的讨论 被引量:1
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作者 李家栋 《化工设备与管道》 CAS 2017年第2期-,共4页
对ASME B31.1及B31.3中关于一次应力的余量可以加到二次应力的计算中这一规定进行了详细的讨论及阐述,并考察了在CAESAR II中激活"liberal allowable stress range"选项对于二次应力计算结果的影响。从结果可知,当该选项被激... 对ASME B31.1及B31.3中关于一次应力的余量可以加到二次应力的计算中这一规定进行了详细的讨论及阐述,并考察了在CAESAR II中激活"liberal allowable stress range"选项对于二次应力计算结果的影响。从结果可知,当该选项被激活时,可以有效解决二次应力超出许用应力范围的情况。 展开更多
关键词 CAESARⅡ 一次应力 二次应力 “liberal allowable STRESS range”
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Study on the Relation between Garment Style and Ease Distribution 被引量:12
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作者 王朝晖 张渭源 《Journal of Donghua University(English Edition)》 EI CAS 2004年第6期31-37,共7页
The shape of body and the ease of garment are the important elements in constructing garment style. However, the distribution of ease in garment is uneven and the curves showing different cross-sections of garment sty... The shape of body and the ease of garment are the important elements in constructing garment style. However, the distribution of ease in garment is uneven and the curves showing different cross-sections of garment style with ease are unavailable in the literature. This information is crucial when the three-dimensional garment style is transformed into two-dimensional garment patterns. Thus, several different X-line style garments are produced by 3D draping technology, and the cubic spline is used to fit the cross sectional curves of BL, WL of body and garment. By comparing cross sections of body and garment, the ease at different location can be derived. Besides, garments in 10 different dimensions and quantities of style ease are included in the current study. By numerical operation on discrete ease data at different location, the fitted functions of ease distribution are obtained. 展开更多
关键词 draping flat pattern design eases allowance EASE distribution curve FITTING
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Impact of climate change on allowable bearing capacity on theQinghai-Tibetan Plateau 被引量:8
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作者 XU Xiao-Ming WU Qing-Bai 《Advances in Climate Change Research》 SCIE CSCD 2019年第2期99-108,共10页
Climate change has a substantial impact on infrastructures in the permafrost on the Qinghai-Tibetan Plateau (QTP). In this study, the mean annual ground temperature (MAGT) and permafrost evolution were investigated in... Climate change has a substantial impact on infrastructures in the permafrost on the Qinghai-Tibetan Plateau (QTP). In this study, the mean annual ground temperature (MAGT) and permafrost evolution were investigated in both the historical (1950-2005) and projected (2006-2099) periods. Then, an allowable bearing capacity model was used to discuss the allowable bearing capacity change on the QTP. Results show that the MAGT increased by 0.36 ℃ during 1950-2005. The MAGT will increase by 0.40 (RCP2.6), 0.79 (RCP4.5), 1.07 (RCP6.0), and 1.75 (RCP8.5)℃C during 2006-2099. In addition, the permafrost area has decreased by 0.195 × 10^6 km2 in 1950-2005. The permafrost area will decrease by 0.232 × 10^6 (RCP2.6), 0.468 × 10^6 (RCP4.5), 0.564 × 10^6 (RCP6.0), and 0.803 × 10^6 (RCP8.5) km2 during 2006-2099. With the degradation of permafrost, the allowable bearing capacity in permafrost zones would decrease accordingly. The decreasing trend is 6 kPa per 10 years in 1950-2005, and will be 0.6 (RCP2.6), 5 (RCP4.5), 7 (RCP6.0), and 11 (RCP8.5) kPa per 10 years during 2006-2099. The most remarkable trend would be observed under RCP8.5. Meanwhile, some scientific advices for the design, construction, operation and maintenance of permafrost engineering in the context of climate change were provided. 展开更多
关键词 Qinghai-Tibetan PLATEAU CLIMATE CHANGE PERMAFROST Allowable BEARING capacity
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Numerical Study of a Novel Procedure for Installing the Tower and Rotor Nacelle Assembly of Offshore Wind Turbines Based on the Inverted Pendulum Principle 被引量:10
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作者 Wilson Guachamin Acero Zhen Gao Torgeir Moan 《Journal of Marine Science and Application》 CSCD 2017年第3期243-260,共18页
Current installation costs of offshore wind turbines(OWTs) are high and profit margins in the offshore wind energy sector are low, it is thus necessary to develop installation methods that are more efficient and pract... Current installation costs of offshore wind turbines(OWTs) are high and profit margins in the offshore wind energy sector are low, it is thus necessary to develop installation methods that are more efficient and practical. This paper presents a numerical study(based on a global response analysis of marine operations) of a novel procedure for installing the tower and Rotor Nacelle Assemblies(RNAs) on bottom-fixed foundations of OWTs. The installation procedure is based on the inverted pendulum principle. A cargo barge is used to transport the OWT assembly in a horizontal position to the site, and a medium-size Heavy Lift Vessel(HLV) is then employed to lift and up-end the OWT assembly using a special upending frame. The main advantage of this novel procedure is that the need for a huge HLV(in terms of lifting height and capacity) is eliminated. This novel method requires that the cargo barge is in the leeward side of the HLV(which can be positioned with the best heading) during the entire installation. This is to benefit from shielding effects of the HLV on the motions of the cargo barge, so the foundations need to be installed with a specific heading based on wave direction statistics of the site and a typical installation season. Following a systematic approach based on numerical simulations of actual operations, potential critical installation activities, corresponding critical events, and limiting(response) parameters are identified. In addition, operational limits for some of the limiting parameters are established in terms of allowable limits of sea states. Following a preliminary assessment of these operational limits, the duration of the entire operation, the equipment used, and weather-and water depth-sensitivity, this novel procedure is demonstrated to be viable. 展开更多
关键词 offshore wind turbine installation crane vessel shielding effects critical events limiting parameters inverted pendulum allowable sea states
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Stability of singular networked control systems with control constraint 被引量:9
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作者 Qiu Zhanzhi Zhang Qingling Zhao Zhiwu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期290-296,共7页
Based on bounded network-induced time-delay, the networked control system is modeled as a linear time-variant singular system. Using the Lyapunov theory and the linear matrix inequality approach, the criteria for dela... Based on bounded network-induced time-delay, the networked control system is modeled as a linear time-variant singular system. Using the Lyapunov theory and the linear matrix inequality approach, the criteria for delay-independent stability and delay-dependent stability of singular networked control systems are derived and transformed to a feasibility problem of linear matrix inequality formulation, which can be solved by the Matlab LMI toolbox, and the feasible solutions provide the maximum allowable delay bound that makes the system stable. A numerical example is provided, which shows that the analysis method is valid and the stability criteria are feasible. 展开更多
关键词 Networked control systems Asymptotical stability Linear matrix inequality Singular controlled plant Control constraint Maximum allowable delay bound.
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