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Turned off Characteristics of Linear Ultrasonic Motor
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作者 Zhang Jun Shi Yunlai +1 位作者 Niu Zijie Liang Dazhi 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第1期49-54,共6页
The high controllability and high resolution control of linear ultrasonic motors depend on effective control of driving signals.For a good control characteristic,step control which the driver output turned off and on ... The high controllability and high resolution control of linear ultrasonic motors depend on effective control of driving signals.For a good control characteristic,step control which the driver output turned off and on was used.Therefore,a novel dual PWM topology structure ultrasonic motor driver was designed and analyzed.According to the characteristics of the circuits,two kinds of hardware turned off methods named methods A and B were discussed.The differences of the voltage applied on motor by different methods were figured out.Finally,a series of experiments were carried out in the clean room to study the influence of step characteristic by different turn off methods.The experimental results show that the steplength was 230 nm by method A and 125 nm by method B,while cycles of driving signals were 6.The method B has a smaller steplength when cycles are 6.The average steplength varies in non-linear while driving cycles changing.The steplength varies approximately in linear while voltage amplitude changing.Therefore,method B is better to implement step control,because it gets a better control in positioning system. 展开更多
关键词 LINEAR ULTRASONIC MOTOR turned OFF CHARACTERISTICS STEP control steplength
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Taishun Wood-turned Toys
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作者 Xu Huading 《China's Foreign Trade》 1994年第4期18-18,共1页
Located along the border between Zhejiang and Fujian provinces, Taishun has exuberant vegetation and rich timber resources because the Xianxialing Mountain range runs across it. About 500 years ago during the Ming Dyn... Located along the border between Zhejiang and Fujian provinces, Taishun has exuberant vegetation and rich timber resources because the Xianxialing Mountain range runs across it. About 500 years ago during the Ming Dynasty, the local people began to use the abundant timber to make various types 展开更多
关键词 Fujian turned timber vegetation abundant BORDER PAINT MAKER SOUTHEAST DYNASTY
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Fluid Flow and Heat Transfer Charateristics in a 180-deg Round Turned Channel with a Perforated Divider
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作者 Rui Xu Rui Xu +4 位作者 Jinliang Hou Li Wang Yanfei Yu Jiaxing Wei Changfeng Li 《Journal of Applied Mathematics and Physics》 2014年第6期411-417,共7页
This study provided a new configuration of the 180-deg round turned channel with a perforated divider, as well as numerically investigated the effect of perforations, including the diameter of perforation and the ange... This study provided a new configuration of the 180-deg round turned channel with a perforated divider, as well as numerically investigated the effect of perforations, including the diameter of perforation and the angel of perforation, on the fluid flow and heat transfer. The numerical results appeared in good agreement with previous experimental data under the same operating conditions. The results indicated that large size and positive angle of perforation changed the fluid flow pattern and the local Nusselt-number distribution fundamentally. It is noteworthy that a more uniform distribution of Nusselt-number was achieved by increasing the diameter of perforation. 展开更多
关键词 180-deg turned CHANNEL Perforated DIVIDER Heat Transfer COMPUTATIONAL FLUID Dynamic
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Baozhusi Hydropower Station turned over formally
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《Electricity》 2001年第1期6-6,共1页
关键词 OVER Baozhusi Hydropower Station turned over formally
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CNPC turned a profit last year
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《China Oil & Gas》 CAS 1995年第1期13-13,共1页
CNPCturnedaprofitlastyearForthefirsttimesince1988,China'sonshorepetroleumindustryturnedaprofitlastyear-thank... CNPCturnedaprofitlastyearForthefirsttimesince1988,China'sonshorepetroleumindustryturnedaprofitlastyear-thankstooilpriceadjust... 展开更多
关键词 CNPC turned a profit last year
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The 15th ITMF Corona-Survey Business situation and expectation have turned negative
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《China Textile》 2022年第5期30-30,共1页
The 15th ITMF Corona-Survey shows that the business situation plunged into negative territory in July 2022.The business situation is worse in Asia than in the rest of the world.Textile machinery is the only segment st... The 15th ITMF Corona-Survey shows that the business situation plunged into negative territory in July 2022.The business situation is worse in Asia than in the rest of the world.Textile machinery is the only segment still in positive territory.Business expectations have also turned negative for the first time since the start of survey in May 2021.South-East Asia and South America are relatively more optimistic,downstream segments as well. 展开更多
关键词 EXPECTATION turned TERRITORY
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A theoretical and deep learning hybrid model for predicting surface roughness of diamond-turned polycrystalline materials 被引量:2
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作者 Chunlei He Jiwang Yan +3 位作者 Shuqi Wang Shuo Zhang Guang Chen Chengzu Ren 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第3期620-644,共25页
Polycrystalline materials are extensively employed in industry.Its surface roughness significantly affects the working performance.Material defects,particularly grain boundaries,have a great impact on the achieved sur... Polycrystalline materials are extensively employed in industry.Its surface roughness significantly affects the working performance.Material defects,particularly grain boundaries,have a great impact on the achieved surface roughness of polycrystalline materials.However,it is difficult to establish a purely theoretical model for surface roughness with consideration of the grain boundary effect using conventional analytical methods.In this work,a theoretical and deep learning hybrid model for predicting the surface roughness of diamond-turned polycrystalline materials is proposed.The kinematic–dynamic roughness component in relation to the tool profile duplication effect,work material plastic side flow,relative vibration between the diamond tool and workpiece,etc,is theoretically calculated.The material-defect roughness component is modeled with a cascade forward neural network.In the neural network,the ratio of maximum undeformed chip thickness to cutting edge radius RT S,work material properties(misorientation angle θ_(g) and grain size d_(g)),and spindle rotation speed n s are configured as input variables.The material-defect roughness component is set as the output variable.To validate the developed model,polycrystalline copper with a gradient distribution of grains prepared by friction stir processing is machined with various processing parameters and different diamond tools.Compared with the previously developed model,obvious improvement in the prediction accuracy is observed with this hybrid prediction model.Based on this model,the influences of different factors on the surface roughness of polycrystalline materials are discussed.The influencing mechanism of the misorientation angle and grain size is quantitatively analyzed.Two fracture modes,including transcrystalline and intercrystalline fractures at different RTS values,are observed.Meanwhile,optimal processing parameters are obtained with a simulated annealing algorithm.Cutting experiments are performed with the optimal parameters,and a flat surface finish with Sa 1.314 nm is finally achieved.The developed model and corresponding new findings in this work are beneficial for accurately predicting the surface roughness of polycrystalline materials and understanding the impacting mechanism of material defects in diamond turning. 展开更多
关键词 diamond turning material-defect roughness component polycrystalline copper neural network simulated annealing algorithm
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White Layer of Hard Turned Surface by Sharp CBN Tool
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作者 张雪萍 宋合川 C.Richard Liu 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第4期377-380,386,共5页
White layers in hard turned surfaces were identified and measured as a function ot turning parameters based on the Taguchi method. It reveals that white layers generate on the machine surface in the absence of tool fl... White layers in hard turned surfaces were identified and measured as a function ot turning parameters based on the Taguchi method. It reveals that white layers generate on the machine surface in the absence of tool flank wear, and white layer depth varies with the different combinations of hard turning parameters. Turning speed has the most important impact on white layer depth, feed rate follows, and cutting depth at last. The white layer generation consequently suggests a strong couple relation to the heat generation and thermal process of hard turning operation. White layer disappears under an optimal combination of turning parameters by Taguchi method. It suggests that a superior surface integrity without white layer is feasible under some selected combinations of turning parameters by a sharp CBN cutting tool. 展开更多
关键词 white layer hard turning hardened bearing steel CBN cutting tool
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Simultaneous Optimization of Correlated Multiple Surface Quality Characteristics of Mild Steel Turned Product
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作者 Saurav DATTA Siba Sankar MAHAPATRA 《Intelligent Information Management》 2010年第1期26-39,共14页
Present work highlights application of utility theory combined with Principal Component Analysis (PCA) and Taguchi’s robust design for simultaneous optimization of correlated multiple surface quality characteristics ... Present work highlights application of utility theory combined with Principal Component Analysis (PCA) and Taguchi’s robust design for simultaneous optimization of correlated multiple surface quality characteristics of mild steel machined product prepared by straight turning operation. The study aims at evaluating the most favorable process environment followed by an optimal parametric combination for achieving high surface quality. Traditional Taguchi based hybrid optimization approaches rely on the assumption that quality indices are uncorrelated or independent. But it is felt that, in practice, there may be some correlation among various quality indices (responses) under consideration. To overcome this limitation of Taguchi approach, the present study proposes application of PCA to convert correlated responses into uncorrelated quality indices called principal components. Finally based on utility theory, Taguchi method has been applied to solve this optimization problem. The study demonstrates detailed methodology and concludes robustness and flexibility of the proposed optimization technique and validates its effectiveness through a case study in which correlated multiple response characteristics of turning operation have been optimized. 展开更多
关键词 UTILITY theory principal component analysis Taguchi’s robust design STRAIGHT TURNING
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洛普替尼
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作者 卢书雨(编译) 赵冬梅(审校) 《中国药物化学杂志》 2025年第3期246-246,共1页
洛普替尼(repotrectinib)是由Turning Point Therapeutics公司研发,于2023年11月15日经美国食品药品监督管理局(FDA)批准上市,商品名为Augtyro。洛普替尼是一种多靶点激酶抑制剂,可以靶向ROS1、TRK和ALK,适用于治疗局部晚期或转移性ROS... 洛普替尼(repotrectinib)是由Turning Point Therapeutics公司研发,于2023年11月15日经美国食品药品监督管理局(FDA)批准上市,商品名为Augtyro。洛普替尼是一种多靶点激酶抑制剂,可以靶向ROS1、TRK和ALK,适用于治疗局部晚期或转移性ROS1阳性非小细胞肺癌(non-small cell lung cancer,NSCLC)成人患者[1]。 展开更多
关键词 Turning Point Therapeutics 洛普替尼 repotrectinib
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Tracking toads from dusk till dawn:linking inter-and intra-individual variation in movement behavior
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作者 Nathalie Jreidini David M.Green 《Current Zoology》 2025年第3期320-328,共9页
Animals can differ in their individual movement behaviors during their daily displacements.Studies of animal movement patterns often disregard the need to understand individual variation in these patterns and the role... Animals can differ in their individual movement behaviors during their daily displacements.Studies of animal movement patterns often disregard the need to understand individual variation in these patterns and the role of this variation in shaping population distributions of movements.To assess the link between individual movements and population distributions,we radio-tracked 13 Fowler's Toads Anaxyrus fowleri in Long Point,Ontario,Canada,after their breeding season.We recorded individual coordinates every 30 min,from the moment they emerged from their burrows around dusk until they burrowed in the morning,and obtained a total of 157 movements.We used the resulting series of step lengths and turning angles in a Hidden Markov Model to estimate movement type as"directed"or"non-directed"We also assigned to each encounter one of 3 space-dependent movement states:"foraging""in transit'or"searching"and found that movement type and state switched within individuals irrespective of time during a single night.We find that switching between movement types varied throughout the night,leading to stochastic within-individual variation in movements,and the distribution of movement distances differed significantly among individuals.Movement states,however,were time-dependent,suggesting displacement routines were similar across individuals.Variation in movement behavior within individuals scales up to result in variation among individuals which,in turn,was found to shape the distribution of the sampled population.Our findings therefore underline the importance of a multi-scale approach in the study of movement. 展开更多
关键词 AMPHIBIAN INDIVIDUALITY RADIO-TRACKING step length turning angle.
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新目标英语八年级(下)Unit 6知识要点归纳
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《中学生英语》 2025年第18期32-32,共1页
【重点词汇】1.work on doing sth.致力于做某事2.once upon a time从前3.continue to do sth.继续做某事4.keep doing sth.坚持做某事5.give up放弃6.instead of代替;反而7.turn...into变成8.get married结婚。
关键词 instead CONTINUE keep doing work TURN get married once upon time give up
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War Hero Turned Civil Servant
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《Beijing Review》 2019年第27期27-27,共1页
Zhang Fuqing, a war hero, has kept a low profi le, devoting himself to serving the people for more than seven decades. The following is an edited excerpt of a Xinhua News Agency report on him:Zhang Fuqing, 95, wears a... Zhang Fuqing, a war hero, has kept a low profi le, devoting himself to serving the people for more than seven decades. The following is an edited excerpt of a Xinhua News Agency report on him:Zhang Fuqing, 95, wears a hat almost every day, not to keep himself warm,but to ease the aftereffect of head injuries he suffered in a fi erce battle over 70 years ago. 展开更多
关键词 ZHANG WAR HERO turned CIVIL SERVANT
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The sweet artistry of blowing sugar figures
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作者 孔云汉 龙菲(指导) 《疯狂英语(初中天地)》 2025年第1期71-71,共1页
In Shandong,the special folk activity of blowing sugar figures during the Spring Festival has a long history.It is said that this skill can be traced back to the Tang Dynasty.At that time,as sugar-making technology im... In Shandong,the special folk activity of blowing sugar figures during the Spring Festival has a long history.It is said that this skill can be traced back to the Tang Dynasty.At that time,as sugar-making technology improved a lot,smart folk craftsmen(工匠)began to use sugar to create various small items.Once heated,sugar turns soft and malleable(可塑的). 展开更多
关键词 SUGAR heated TURNS
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NEWS ROUNDUP
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《ChinAfrica》 2025年第4期8-10,共3页
Boosting Birth Rates,Generous childcare subsidies have been reported across China as part of the country’s holistic efforts to boost birth rates,making news headlines and sparking discussions.The latest news came fro... Boosting Birth Rates,Generous childcare subsidies have been reported across China as part of the country’s holistic efforts to boost birth rates,making news headlines and sparking discussions.The latest news came from Hohhot,capital of north China’s Inner Mongolia Autonomous Region.The city announced this week that it will offer a one-time subsidy of 10,000 yuan($1,394)to couples having their first child.A second child will receive 10,000 yuan per year until he/she reaches five years old.For the third child or more,the annual subsidy is 10,000 yuan until the child turns 10. 展开更多
关键词 discussions TURNS BOOST
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What changes are needed for the outdoor industry's sustainable transformation in 2025?
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作者 Zhao Xinhua 《China Textile》 2025年第1期14-15,共2页
The year 2024 is also a turning point in the outdoor gear industry's commitment to sustainability,This shift towards eco-friendly products is not just a trend but a response to a growing awareness of environmental... The year 2024 is also a turning point in the outdoor gear industry's commitment to sustainability,This shift towards eco-friendly products is not just a trend but a response to a growing awareness of environmental conservation.Manufacturers are increasingly focusing on reducing the ecological footprint of their products,utilizing recycled materials,and adopting sustainable manufacturing processes.This transformation is driven by a combination of consumer demand,environmental responsibility,and technological advancements. 展开更多
关键词 TRANSFORMATION TURNING SUSTAINABLE
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TURNING BACK THE CLOCKS——Xizang Museum teams up with other museums to revive relics
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作者 Kang Caiqi 《China's Tibet》 2025年第1期33-35,共3页
Located in the southeast corner of Norbulingka Palace Park in Lhasa,the Xizang Museum stands out as a facility integrating contemporary technology,design and practices with the regional characteristics of Xizang Auton... Located in the southeast corner of Norbulingka Palace Park in Lhasa,the Xizang Museum stands out as a facility integrating contemporary technology,design and practices with the regional characteristics of Xizang Autonomous Region,southwest China.The museum houses over 520,000 cultural relics,including silk pieces,religious instruments,ancient books and documents,porcelain and jade articles,enamel vessels,and silverware,as well as Thangka paintings. 展开更多
关键词 RELIGIOUS silver TURN
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What Fun Apps Do You Use?
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作者 Mana Chiu 《空中英语教室(初级版.大家说英语)》 2025年第1期29-30,53,共3页
Every one has heard of apps such as TikTok,Google and Spotify.But have you ever heard of these?The app Done helps you meet your goals and finish tasks.It can help you build good habits and quit bad ones.Walkr is an ap... Every one has heard of apps such as TikTok,Google and Spotify.But have you ever heard of these?The app Done helps you meet your goals and finish tasks.It can help you build good habits and quit bad ones.Walkr is an app that turns exercise into a fun adventure. 展开更多
关键词 app GOOGLE TURNS
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An activated fluorescent probe to monitor NO fluctuation in Parkinson’s disease
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作者 Tao Liu Xuwei Han +5 位作者 Xueyi Sun Weijie Zhang Ke Gao Runan Min Yuting Tian Caixia Yin 《Chinese Chemical Letters》 2025年第3期341-344,共4页
The imbalance of nitric oxide(NO)homeostasis in the brain is closely related to the occurrence of Parkinson’s disease(PD).Therefore,revealing the fluctuation of NO in brain is crucial for understanding the pathophysi... The imbalance of nitric oxide(NO)homeostasis in the brain is closely related to the occurrence of Parkinson’s disease(PD).Therefore,revealing the fluctuation of NO in brain is crucial for understanding the pathophysiological processes.However,currently developed NO probes are unsuitable for this purpose due to their poor blood-brain barrier permeability.Herein,a fluorescent probe(PO-NH)with blood-brain barrier crossing capability and high selectivity for NO was developed.Under the NO mediation,the photoinduced electron transfer(PET)process of the probe was blocked,giving an intensive fluorescence enhancement(F/F_(0)=15).Moreover,PO-NH can be used to effectively monitor changes in intracellular NO levels.Significantly,due to excellent blood-brain barrier crossing ability and near-infrared(NIR)emission,PO-NH is suitable for in vivo imaging of NO in the brain and illustrating with the deterioration of PD,the level of NO gradually increased in the brain of PD mice.We believe that PO-NH may provide a beneficial tool for understanding the biological function of NO in the brain and revealing the complex connection between NO and PD. 展开更多
关键词 Blood brain barrier Nitric oxide Fluorescent probe Turn off/on Parkinson’s disease
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A Directional Locomotion Control of Cyborg Locusts for Complex Outdoor Environments
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作者 Xin Huang Tiancheng Li +2 位作者 Kaixuan Sun Meisong Yuan Bo Yang 《Journal of Bionic Engineering》 2025年第2期596-607,共12页
The ability of cyborg locusts to achieve directional movement in complex outdoor environments is critical for search and rescue missions.Currently,there is a lack of research on motion control for cyborg locusts in ou... The ability of cyborg locusts to achieve directional movement in complex outdoor environments is critical for search and rescue missions.Currently,there is a lack of research on motion control for cyborg locusts in outdoor settings.In this study,we developed cyborg locusts capable of performing directional locomotion in intricate outdoor environments,including jumping over obstacles,climbing slopes,traversing narrow pipelines,and accurately reaching predetermined targets along specified routes.We designed a miniature electrical backpack(10 mm×10 mm,0.75 g)capable of receiving stimulus parameters(frequency,duty ratio,and stimulation time)via Bluetooth commands from mobile phones.Electrical stimulation of locust sensory organs,such as the antennae and cercus,induced turning and jumping behaviors.Experi-mental testing of locust movement control was conducted under outdoor conditions with a short electrical stimulation interval.Results showed a positive correlation between locust turning angles and electrical stimulation parameters within a specified range,with an average jumping height exceeding 10 cm.Additionally,the success rate of locust turning and jumping behaviors correlated positively with the interval time between electrical stimulations.Adjusting these intervals during forward crawling phases increased the likelihood of the locusts jumping again.In conclusion,this study success-fully achieved directional locomotion control of cyborg locusts outdoors,providing insights and references for advancing search and rescue capabilities. 展开更多
关键词 Cyborg locusts Turning and jumping control Directional locomotion Search and rescue
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