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Concurrent Design on Three-Legged Jacket Structure and Transition Piece of Offshore Wind Turbine by Exploiting Topology Optimization
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作者 Yiming Zhou Jinhua Zhang +5 位作者 Kai Long Ayesha Saed Yutang Chen Rongrong Geng Tao Tao Xiaohui Guo 《Computer Modeling in Engineering & Sciences》 2025年第5期1743-1761,共19页
The jacket structure and transition piece comprise the supporting structure of a bottom-fixed offshore wind turbine(OWT)connected to the steel tower,which determines the overall structural dynamic performance of the e... The jacket structure and transition piece comprise the supporting structure of a bottom-fixed offshore wind turbine(OWT)connected to the steel tower,which determines the overall structural dynamic performance of the entire OWT.Ideally,optimal performance can be realized by effectively coordinating two components,notwithstanding their separate design processes.In pursuit of this objective,this paper proposes a concurrent design methodology for the jacket structure and transition piece by exploiting topology optimization(TO).The TO for a three-legged jacket foundation is formulated by minimizing static compliance.In contrast to conventional TO,two separated volume fractions are imposed upon the structural design domain of the jacket structure and transition piece to ensure continuity.A 5 MW(megawatt)OWT supported by a four-legged or three-legged jacket substructure is under investigation.The external loads are derived from various design load cases that are acquired using the commercial software platform DNV Bladed(Det Norske Veritas).Through a comparative analysis of the fundamental frequency and maximum nodal deformation,it was found that the optimized solution demonstrates a reduced weight and superior stiffness.The findings demonstrate the present concurrent design approach using TO can yield significant benefits by reducing the overall design cycle and enhancing the feasibility of the final design. 展开更多
关键词 Offshore wind turbine topology optimization jacket structure transition piece design load case
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Changbaishan Volcanism:Is Seamount Subduction the Missing Piece?
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作者 Xiaobo He Mingli He +4 位作者 Yibing Li Jiashun Hu Fabin Pan Zhensheng Wang Jianshe Lei 《Journal of Earth Science》 2025年第5期2337-2340,共4页
0 INTRODUCTION Changbaishan volcanism,located on the border of China and North Korea,has been a subject of extensive research due to its unique geological features and active volcanic history(Wan et al.,2024).Two prim... 0 INTRODUCTION Changbaishan volcanism,located on the border of China and North Korea,has been a subject of extensive research due to its unique geological features and active volcanic history(Wan et al.,2024).Two primary models have been proposed to explain the origin of Changbaishan volcanism(CV). 展开更多
关键词 missing piece changbaishan volcanism cv active volcanic history seamount subduction changbaishan volcanismlocated research models Changbaishan volcanism geological features
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Considerations in the management of single-piece intraocular lenses outside the capsular bag
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作者 Anna K Junk 《World Journal of Ophthalmology》 2014年第3期87-91,共5页
AIM: To investigate the outcomes of off label singlepiece acrylic intraocular lenses(SPA-IOL) ciliary sulcus placement compared to three-piece IOL(3P-IOL). METHODS: The charts of eight consecutive eyes of patients who... AIM: To investigate the outcomes of off label singlepiece acrylic intraocular lenses(SPA-IOL) ciliary sulcus placement compared to three-piece IOL(3P-IOL). METHODS: The charts of eight consecutive eyes of patients who received sulcus-placed SPA-IOLs between 2006 and 2009 were reviewed. None of the patients underwent IOL exchange. Charts of six age-matched patients who received sulcus placed 3P-IOLs were reviewed as a control group. RESULTS: Mean follow up was 16 mo for SPA-IOL and 23 mo for 3P-IOL. Five of 8 patients in the SPA-IOL group required chronic use of IOP lowering medications at final follow up. Of these, one patient needed glaucoma implant surgery for uncontrolled IOP. One patient in the 3P-IOL group used chronic aqueous suppression pre- and postoperatively. Four of eight eyes with SPAIOL were treated with chronic topical steroids and or non-steroidal anti-inflammatory drugs for cystoid macu-la edema, chronic uveitis, pigment dispersion syndrome or a combination of the above, compared to none in the control group. Mean best-corrected visual acuity was 20/35 in the SPA-IOL group and 20/47 in the 3PIOL group.CONCLUSION: Sulcus placed SPA-IOLs are associated with increased ocular morbidity. In select cases good visual acuity may be achieved. Due to postoperative rotation of sulcus placed toric SPA-IOLs stable astigmatism correction cannot be achieved. Alternative intraocular lenses should be considered when in-the-bag placement of SPA-IOL is not possible. 展开更多
关键词 Cataract surgery Sulcus intraocular lens implant Single piece intraocular lenses Three piece intraocular lenses Posterior capsule tear Cataract surgery complication Pigment dispersion Cystoid macula edema Anterior vitrectomy
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针对BitTorrent协议中Piece消息的隐写分析方法 被引量:1
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作者 邢俊俊 翟江涛 刘伟伟 《计算机应用与软件》 北大核心 2020年第5期315-320,共6页
网络隐写是当前网络攻击中常见的一种隐蔽通信方式,给网络安全造成了极大隐患。BitTorrent网络作为一种使用极为广泛的协议,拥有巨大流量,是隐藏信息的极佳载体。近来,有研究者提出了一种基于Piece消息的网络隐写方法,公开文献中尚无有... 网络隐写是当前网络攻击中常见的一种隐蔽通信方式,给网络安全造成了极大隐患。BitTorrent网络作为一种使用极为广泛的协议,拥有巨大流量,是隐藏信息的极佳载体。近来,有研究者提出了一种基于Piece消息的网络隐写方法,公开文献中尚无有效的检测算法。针对此,提出一种基于多特征分类的检测方法。提取正常和含密Piece消息数据流;提取网络数据流时间序列的均值、方差与信息熵特征;使用SVM分类器给出检测结果。实验结果显示,在观测窗口为1000个数据包时,该方法对基于Piece消息隐写的检测率可达94.7%。 展开更多
关键词 BITTORRENT网络 piece消息 隐写检测 多特征 SVM分类器 信息安全
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Torsional vibration analysis of lathe spindle system with unbalanced workpiece 被引量:6
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作者 郭瑞 JANG Sung-Hyun CHOI Young-Hyu 《Journal of Central South University》 SCIE EI CAS 2011年第1期171-176,共6页
For the purpose of analyzing the torsional vibration caused by the gravitational unbalance torque arisen in a spindle system when it is machining heavy work piece,a 10-DOF lumped parameter model was made for the machi... For the purpose of analyzing the torsional vibration caused by the gravitational unbalance torque arisen in a spindle system when it is machining heavy work piece,a 10-DOF lumped parameter model was made for the machine tool spindle system with geared transmission.By using the elementary method and Runge-Kutta method in Matlab,the eigenvalue problem was solved and the pure torsional vibration responses were obtained and examined.The results show that the spindle system cannot operate in the desired constant rotating speed as far as the gravitational unbalance torque is engaged,so it may cause bad effect on machining accuracy.And the torsional vibration increases infinitely near the resonant frequencies,so the spindle system cannot operate normally during these spindle speed ranges. 展开更多
关键词 unbalanced work piece gravitational unbalance torque torsional vibration spindle system geared transmission
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FPSO船体结构建造Piece Mark进度报表开发与应用 被引量:1
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作者 姜秀斌 沈彬 +1 位作者 吴涛 刘镇东 《现代计算机》 2021年第18期138-141,共4页
本文针对国外业主对Piece Mark表的提交需求,结合海洋石油工程股份有限公司的PCMS系统,采用VSTO编程技术,对该进度报表进行了研究和开发,并在某国外FPSO船体建造项目中进行了应用。
关键词 piece Mark PCMS VSTO 进度报表
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A Dual-Platform Laser Scanner for 3D Reconstruction of Dental Pieces 被引量:4
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作者 Shuming Yang Xinyu Shi +1 位作者 Guofeng Zhang Changshuo Lv 《Engineering》 SCIE EI 2018年第6期796-805,共10页
This paper presents a dual-platform scanner for dental reconstruction based on a three-dimensional(3D)laser-scanning method.The scanner combines translation and rotation platforms to perform a holistic scanning.A hybr... This paper presents a dual-platform scanner for dental reconstruction based on a three-dimensional(3D)laser-scanning method.The scanner combines translation and rotation platforms to perform a holistic scanning.A hybrid calibration method for laser scanning is proposed to improve convenience and precision.This method includes an integrative method for data collection and a hybrid algorithm for data processing.The integrative method conveniently collects a substantial number of calibrating points with a stepped gauge and a pattern for both the translation and rotation scans.The hybrid algorithm,which consists of a basic model and a compensation network,achieves strong stability with a small degree of errors.The experiments verified the hybrid calibration method and the scanner application for the measurement of dental pieces.Two typical dental pieces were measured,and the experimental results demonstrated the validity of the measurement that was performed using the dual-platform scanner.This method is effective for the 3D reconstruction of dental pieces,as well as that of objects with irregular shapes in engineering fields. 展开更多
关键词 Laser SCANNING Hybrid CALIBRATION NEURAL network DENTAL pieces
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Identification of Kinematic Errors of Five-axis Machine Tool Trunnion Axis from Finished Test Piece 被引量:3
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作者 ZHANG Ya FU Jianzhong CHEN Zichen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第5期999-1007,共9页
Compared with the traditional non-cutting measurement,machining tests can more accurately reflect the kinematic errors of five-axis machine tools in the actual machining process for the users.However,measurement and c... Compared with the traditional non-cutting measurement,machining tests can more accurately reflect the kinematic errors of five-axis machine tools in the actual machining process for the users.However,measurement and calculation of the machining tests in the literature are quite difficult and time-consuming.A new method of the machining tests for the trunnion axis of five-axis machine tool is proposed.Firstly,a simple mathematical model of the cradle-type five-axis machine tool was established by optimizing the coordinate system settings based on robot kinematics.Then,the machining tests based on error-sensitive directions were proposed to identify the kinematic errors of the trunnion axis of cradle-type five-axis machine tool.By adopting the error-sensitive vectors in the matrix calculation,the functional relationship equations between the machining errors of the test piece in the error-sensitive directions and the kinematic errors of C-axis and A-axis of five-axis machine tool rotary table was established based on the model of the kinematic errors.According to our previous work,the kinematic errors of C-axis can be treated as the known quantities,and the kinematic errors of A-axis can be obtained from the equations.This method was tested in Mikron UCP600 vertical machining center.The machining errors in the error-sensitive directions can be obtained by CMM inspection from the finished test piece to identify the kinematic errors of five-axis machine tool trunnion axis.Experimental results demonstrated that the proposed method can reduce the complexity,cost,and the time consumed substantially,and has a wider applicability.This paper proposes a new method of the machining tests for the trunnion axis of five-axis machine tool. 展开更多
关键词 five-axis machine tool kinematic errors trunnion axis test piece error-sensitive directions
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Surface Magnet Gears with a New Magnet Arrangement and Optimal Shape of Stationary Pole Pieces 被引量:3
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作者 Tomoyuki Fujita Yoshinori Ando +4 位作者 Kosuke Nagaya Masaru Oka Takashi Todaka Masato Enokizono Kazunobu Sugiura 《Journal of Electromagnetic Analysis and Applications》 2013年第6期243-249,共7页
In mechanical gear systems, dust, noise, vibration, and tooth wear are generated by frictions among gear teeth, and suppressing friction requires lubrication. Magnetic gears transmit torque by magnetic forces without ... In mechanical gear systems, dust, noise, vibration, and tooth wear are generated by frictions among gear teeth, and suppressing friction requires lubrication. Magnetic gears transmit torque by magnetic forces without contact and so avoid contact-related problems. The present paper discusses magnet arrangements and the shape of stationary gear teeth to improve transmission torque in surface magnet type magnetic gear transmission mechanisms. 展开更多
关键词 Magnetic GEAR STATIONARY Pole piece Optimal Shape HALBACH MAGNET Arrangement
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Rapid recognition of Chinese herbal pieces of Areca catechu by different concocted processes using Fourier transform mid-infrared and near-infrared spectroscopy combined with partial least-squares discriminant analysis 被引量:12
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作者 Hai-Yan Fu Dong-Chen Huang +2 位作者 Tian-Ming Yang Yuan-Bin She Hao Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第7期639-642,共4页
Rapid and sensitive recognition of herbal pieces according to different concocted processing is crucial to quality control and pharmaceutical effect. Near-infrared (NIR) and mid-infrared (MIR) technology combined ... Rapid and sensitive recognition of herbal pieces according to different concocted processing is crucial to quality control and pharmaceutical effect. Near-infrared (NIR) and mid-infrared (MIR) technology combined with supervised pattern recognition based on partial least-squares discriminant analysis (PLSDA) was attempted to classify and recognize six different concocted processing pieces of 600 Areca catechu L. samples and the influence of fingerprint information preprocessing methods on recognition performance was also investigated in this work. Recognition rates of 99.24%, 100% and 99.49% for original fingerprint, multiple scatter correct (MSC) fingerprint and second derivative (2nd derivative) fingerprint of NIR spectra were achieved by PLSDA models, respectively. Meanwhile, a perfect recognition rate of 100% was obtained for the above three fingerprint models of MIR spectra. In conclusion, PLSDA can rapidly and effectively extract otherness of fingerprint information from NIR and MIR spectra to identify different concocted herbal pieces ofA. catechu. 展开更多
关键词 NIR and MIR spectroscopy Partial least-squares discriminant analysis Different concocted processing herbal pieces
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Development of sandwich joining piece to fabricate segmented half-Heusler/skutterudite thermoelectric joints 被引量:1
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作者 Wei-An Wang Xiao-Ya Li +4 位作者 Yun-Fei Xing Ming Gu Long-Hui Fang Ye-Feng Bao Jin-Hui Fan 《Rare Metals》 CSCD 2021年第7期1966-1970,共5页
Sn/Ni-Sn/Sn sandwich joining piece was developed and applied to fabricate segmented half-Heusler/skutterudite thermoelectric joints,and high-temperature service behavior of the joints was studied.The microstructure an... Sn/Ni-Sn/Sn sandwich joining piece was developed and applied to fabricate segmented half-Heusler/skutterudite thermoelectric joints,and high-temperature service behavior of the joints was studied.The microstructure and contact resistance of the joint before and after aging were investigated.The joints are well bonded and no cracks appear at the interfaces of the joint before and after aging,which can be attributed to the formation of high-melting point intermetallic compounds.The electrical resistance crosses the joining layer smoothly and the contact resistance is low.These results show that the sandwich joining piece is effective and flexible,and promising for the preparation of segmented thermoelectric devices. 展开更多
关键词 Sandwich joining piece Segmented thermoelectric joint Microstructure Contact resistance
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“a piece of+名词”与其修饰语 被引量:1
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作者 余尚文 《语言教育》 1993年第3期25-25,共1页
在“a piece of+名词”结构中,作修饰语的形容词出现在piece 之前与出现在名词之前这两种情况都有。例如: a piece of good luck;a piece of bad news 与 a finepiece of work;a delicate piece of mechanism 等等。还可以举出许多例子... 在“a piece of+名词”结构中,作修饰语的形容词出现在piece 之前与出现在名词之前这两种情况都有。例如: a piece of good luck;a piece of bad news 与 a finepiece of work;a delicate piece of mechanism 等等。还可以举出许多例子。那么,这是否就等于说该结构中的形容词可以任意放在上述两个位置中的一个上呢?也不尽然。笔者查阅了若干词典。 展开更多
关键词 piece a piece of FURNITURE EMOTION 外籍专家 PRIVATE ordinary music
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Ocular hypertension secondary to obesity: cortisol, the missing piece of the pathophysiological puzzle?
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作者 Andrej Belancic Marija Krpina +1 位作者 Sanja Klobucar Majanovic Maja Merlak 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第6期1050-1051,共2页
Dear Editor,Obesity has nowadays become a global public health challenge due to its rapidly growing prevalence and interconnection with a wide spectrum of comorbidities.
关键词 Ocular hypertension secondary obesity CORTISOL the missing piece of the pathophysiological PUZZLE
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Ten Years Dedication Blossom on the Delicate Piece——Ordifen Cup 2014 China Lingerie Design ContestLaunches in Beijing
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作者 Anne Zhang 《China's Foreign Trade》 2014年第Z2期64-64,共1页
In the afternoon of October 29th,2014,Ordifen Cup 2014 China Lingerie Design Contest unveiled during China Fashion Week.Jointly held by China Fashion Association and Ordifen International Group,the contest presented u... In the afternoon of October 29th,2014,Ordifen Cup 2014 China Lingerie Design Contest unveiled during China Fashion Week.Jointly held by China Fashion Association and Ordifen International Group,the contest presented us a grand feast with the essence of Ordifen’s ten years dedication.Tiny but delicate,the lingerie condenses the charisma of both culture and fashion in the small piece of cloth.Time goes so fast all in the blink of an eye. 展开更多
关键词 ESSENCE AFTERNOON cloth fashion piece perfect FELL
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A systematic review and meta-analysis to compare the effects of Chinese herbal pieces and granule in different diseaseherbal pieces
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作者 Yang Yu Lu Wang +1 位作者 Jing-Bo Zhai Chang-Gang Sun 《TMR Integrative Medicine》 2020年第18期1-27,共27页
Objective:Compared to Chinese herbal piecesherbal pieces,the quality of TCM granule is stable and controllable,it is also a convenient alternative to decocting herbs.However,whether they are as clinically effective as... Objective:Compared to Chinese herbal piecesherbal pieces,the quality of TCM granule is stable and controllable,it is also a convenient alternative to decocting herbs.However,whether they are as clinically effective as Chinese herbal piecesherbal pieces is still controversial.In this study,a systematic review and meta-analysis were performed to assess the clinical efficacy of TCM granules and Chinese herbal piecesherbal pieces.Methods:A search of online databases for eligible articles was performed,including PubMed,Embase,Cochrane Library,Web of Science,China National Knowledge Internet,WanFang,and Chongqing VIP Information,searching from the inception of these databases to 2020.The Cochrane Handbook 5.1.0 was used to independently identify the trials,extract data,and assess the risk of bias.The meta-analysis was performed via RevMan 5.3 software.Results:A total of 98 eligible articles were included.After classification and statistical analysis of the related diseases,a meta-analysis was performed on 8 types of illnesses(cold,hypertension,migraine,osteoporosis,and diseases of the digestive system,such as gastritis,gastric ulcer,colitis,epigastric pain)included in 66 randomized controlled trials to compare the clinical efficacy and adverse events of TCM granules and Chinese herbal pieces.Meta-analysis showed that compared with Chinese herbal piecesherbal pieces,TCM granules had similar effectiveness and safety in treating cold,hypertension,and osteoporosis,but a higher response rate in migraines and a better effect in reducing migraine duration and higher response rate on diseases of the digestive system.Conclusion:Compared with the traditional decoctions,TCM formula granules had the same efficacy and safety,moreover,they had higher efficacy and safety in treating migraines and digestive system diseases. 展开更多
关键词 TCM granules TCM herbal pieces Cold Hypertension Osteoporosis Digestive system diseases MIGRAINES META-ANALYSIS
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Single Piece Dental Implant: A Remedy for Atrophic Ridges: Review
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作者 Shakhawan M. Ali Payman Kh. Mahmud +1 位作者 Kawan S. Othman Abduljaleel A. Samad 《International Journal of Otolaryngology and Head & Neck Surgery》 2019年第6期271-282,共12页
Implant placement in severely atrophic jaws is especially challenging because of the poor quality and quantity of the future implant bed. Although various bone augmentation procedure like ridge augmentation, sinus lif... Implant placement in severely atrophic jaws is especially challenging because of the poor quality and quantity of the future implant bed. Although various bone augmentation procedure like ridge augmentation, sinus lift these procedures are possible today but it may lead to surgical morbidity they increase the risks and costs of dental implant treatment as well as the number of necessary operations. Also sometimes the patient is not agreeing for such extensive surgical procedures, according to the well-known implantological rules for dental restorations, crestal implants are indicated in situations when an adequate vertical bone supply is given but single piece dental implant (basal implants) is a viable treatment option derives support from the basal bone area which usually remains free from the infection and less prone to resorption. 展开更多
关键词 Single piece Dental Implant (Basal Implants) Crestal IMPLANTS ORTHOPAEDIC IMPLANTS Atrophied ALVEOLAR Ridge
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Pieces targets comparision of RBC components before and after leucocyte removal filter
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《中国输血杂志》 CAS CSCD 2001年第S1期342-,共1页
关键词 RBC pieces targets comparision of RBC components before and after leucocyte removal filter
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寻找日本连载动画《One Piece》成功的钥匙
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作者 熊千淇 《戏剧之家》 2015年第24期86-87,共2页
《One Piece》又名《海贼王》,于1997年开始连载以来,其影响力不容小觑,被誉为日本三大国民动漫之一。这是一部连载超过十年的动画作品,本文试从创作者、叙事、文化、配乐等方面浅析《One Piece》成功的原因。
关键词 《One piece 尾田荣一郎 叙事 配乐
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A Trove of Masterpieces
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作者 ZHANG HUI 《China Today》 2023年第11期34-37,共4页
The special exhibition“The Greats of Six Centuries:Masterpieces from the Museo Nacional Thyssen-Bornemisza,”held in Shanghai provides profound insight into the evolution of Western culture,lifestyle,and social lands... The special exhibition“The Greats of Six Centuries:Masterpieces from the Museo Nacional Thyssen-Bornemisza,”held in Shanghai provides profound insight into the evolution of Western culture,lifestyle,and social landscapes over the 600 years. 展开更多
关键词 MASTER LANDSCAPE pieces
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The analysis of structural complexity of Piano Pieces "dedicated to Alice"
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作者 Junzhong ZHANG 《International Journal of Technology Management》 2014年第11期57-59,共3页
Beethoven is a famous German pianist, composer, and conductor, and he set the culmination of Western classical, created a romantic music camp precedent. The size of his music in general is very ambitious, mostly conce... Beethoven is a famous German pianist, composer, and conductor, and he set the culmination of Western classical, created a romantic music camp precedent. The size of his music in general is very ambitious, mostly concertos, symphonies, operas and other large works, technical approach and structure used is quite complex, people are left with a deep impression. But it works, while small piano pieces, also has music research value, "dedicated to Alice" is one of the few Beethoven piano pieces. This paper focuses on creative background "dedicated to Alice," this elaborate piano works by the complexity of the analysis of the structure of this work is that it reflects the author' s ideological soul to explore their musical value. 展开更多
关键词 BEETHOVEN Piano pieces "dedicated to Alice" complex structures
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