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Dynamic Analysis of a 10 MW Floating Offshore Wind Turbine Considering the Tower and Platform Flexibility
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作者 GAO Shan ZHANG Lixian +3 位作者 SHI Wei WANG Wenhua WANG Bin LI Xin 《Journal of Ocean University of China》 CAS CSCD 2024年第2期358-370,共13页
Recently,semisubmersible floating offshore wind turbine technologies have received considerable attention.For the coupled simulation of semisubmersible floating offshore wind energy,the platform is usually considered ... Recently,semisubmersible floating offshore wind turbine technologies have received considerable attention.For the coupled simulation of semisubmersible floating offshore wind energy,the platform is usually considered a rigid model,which could affect the calculation accuracy of the dynamic responses.The dynamic responses of a TripleSpar floating offshore wind turbine equipped with a 10 MW offshore wind turbine are discussed herein.The simulation of a floating offshore wind turbine under regular waves,white noise waves,and combined wind-wave conditions is conducted.The effects of the tower and platform flexibility on the motion and force responses of the TripleSpar semisubmersible floating offshore wind turbine are investigated.The results show that the flexibility of the tower and platform can influence the dynamic responses of a TripleSpar semisubmersible floating offshore wind turbine.Considering the flexibility of the tower and platform,the tower and platform pitch motions markedly increased compared with the fully rigid model.Moreover,the force responses,particularly for tower base loads,are considerably influenced by the flexibility of the tower and platform.Thus,the flexibility of the tower and platform for the coupled simulation of floating offshore wind turbines must be appropriately examined. 展开更多
关键词 floating offshore wind turbine TripleSpar semisubmersible platform rigidity and flexibility platform coupled simulation
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On the Polygonal Wear Evolution of Heavy-Haul Locomotive Wheels due to Wheel/Rail Flexibility and Its Mitigation Measures
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作者 Yunfan Yang Feifan Chai +3 位作者 Pengfei Liu Liang Ling Kaiyun Wang Wanming Zhai 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期40-61,共22页
Wheel polygonal wear can immensely worsen wheel/rail interactions and vibration performances of the train and track,and ultimately,lead to the shortening of service life of railway components.At present,wheel/rail med... Wheel polygonal wear can immensely worsen wheel/rail interactions and vibration performances of the train and track,and ultimately,lead to the shortening of service life of railway components.At present,wheel/rail medium-or high-frequency frictional interactions are perceived as an essential reason of the high-order polygonal wear of railway wheels,which are potentially resulted by the flexible deformations of the train/track system or other external excitations.In this work,the effect of wheel/rail flexibility on polygonal wear evolution of heavy-haul locomotive wheels is explored with aid of the long-term wheel polygonal wear evolution simulations,in which different flexible modeling of the heavy-haul wheel/rail coupled system is implemented.Further,the mitigation measures for the polygonal wear of heavy-haul locomotive wheels are discussed.The results point out that the evolution of polygonal wear of heavy-haul locomotive wheels can be veritably simulated with consideration of the flexible effect of both wheelset and rails.Execution of mixed-line operation of heavy-haul trains and application of multicut wheel re-profiling can effectively reduce the development of wheel polygonal wear.This research can provide a deep-going understanding of polygonal wear evolution mechanism of heavy-haul locomotive wheels and its mitigation measures. 展开更多
关键词 Heavy-haul locomotive Wheel polygonal wear Wheel/rail flexibility Long-term polygonal wear evolution Mitigation measures
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Analysis on the Translation Methods of the Reported Speech in German Academic Papers-Taking the Translation of“Die Internationalisierung der deutschen Hochschulen”as an Example
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作者 WANG Rui CHEN Qi 《Journal of Literature and Art Studies》 2024年第9期802-807,共6页
Reporting is essential in language use,including the re-expression of other people’s or self’s words,opinions,psychological activities,etc.Grasping the translation methods of reported speech in German academic paper... Reporting is essential in language use,including the re-expression of other people’s or self’s words,opinions,psychological activities,etc.Grasping the translation methods of reported speech in German academic papers is very important to improve the accuracy of academic paper translation.This study takes the translation of“Internationalization of German Universities”(Die Internationalisierung der deutschen Hochschulen),an academic paper of higher education,as an example to explore the translation methods of reported speech in German academic papers.It is found that the use of word order conversion,part of speech conversion and split translation methods can make the translation more accurate and fluent.This paper helps to grasp the rules and characteristics of the translation of reported speech in German academic papers,and also provides a reference for improving the quality of German-Chinese translation. 展开更多
关键词 academic paper reported speech TRANSLATION
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Ureteroscopy with Holmium: YAG Laser—A Initial Study in the Urology Department of the Pr Bocar Sidy Sall University Hospital of Kati
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作者 Amadou Kassogue Idrissa Sissoko +11 位作者 Daouda Sangare Moussa Salifou Diallo Hamed Sylla Mahamadou Traore Boureima Coulibaly Salia Coulibaly Modibo Diakite Modibo Togola Fadima Tall Ilias Guindo Ben Naoum Kamel Mamadou Lamine Diakite 《Open Journal of Urology》 2024年第4期207-216,共10页
Introduction: Ureteroscopy is a minimally invasive endoscopic surgery which provides access to the ureter, pyelon and calyceal cavities via the urethra and the bladder. Laser ureteroscopy uses the laser as an energy s... Introduction: Ureteroscopy is a minimally invasive endoscopic surgery which provides access to the ureter, pyelon and calyceal cavities via the urethra and the bladder. Laser ureteroscopy uses the laser as an energy source to treat the stone and eliminate it naturally. Minimally invasive endoscopic methods are struggling to become popular in sub-Saharan African countries, especially for the upper urinary tract. The objective of our work was to report the results of our first laser ureteroscopy experience in the department. Materials and Methods: This was a prospective and descriptive study running from December 1, 2023 to February 19, 2024. Included in our study was any case of upper urinary tract stone operated by Laser ureteroscopy. The characteristics of the lithiasis were determined by CT scan. Sterilization of urine was verified by carrying out a cytobacteriological examination of urine. Ureteral lithiasis was approached by semi-rigid ureteroscopy. Renal lithiasis was immediately addressed by flexible ureteroscopy. Ureteroscopy was coupled with a Holmium YAG laser. A double J ureteral catheter was placed after the operation. A 230 µm laser fiber was used in each case with a generator with a power of 35 watts (Storz Calculase III type). An access sheath was used in all cases of flexible ureteroscopy. The parameters studied were: sociodemographic characteristics, lithiasis (site, size, number, density, topography), type of anesthesia, duration of laser use, duration of intervention, postoperative outcomes. Data entry and analysis were carried out using the software (Word 2016 and SPSS). Result: We collected 30 cases of laser ureteroscopy. The average age was 37 years with extremes of 9 and 79 years. The male gender was more represented. The most common age group was 24-39 years old. Renal colic was the most frequent reason for admission, 12 patients (40%). On physical examination, lumbar tenderness was present in 47% (14 patients). ECBU was positive in 4 patients (13%). CT scan was performed in all our patients before the intervention. The average stone size was 12 mm and the largest was 23 mm. The majority of stones, i.e. 59% (18 patients), had a density greater than 1000 HU. The stone was unique in 19 patients (63%). The location of the stone was pyelic in 8 patients or 27%. An impact on the upper urinary tract was found in 16 of our patients or 53%. General anesthesia was used in 25 patients (83%). A digital flexible ureteroscopy was used in 24 patients and a semi-rigid ureteroscopy (URS) in 6 patients. Full-course fragmentation was the most used therapeutic method, 9 patients or 32%. The average duration of interventions was 61 minutes. Drainage by double J catheter at the end of the procedure was performed in all our patients. The length of hospitalization was 24 hours. Only one case of failure in the USSR was recorded, and one case of failure was in the semi-rigid URS. Conclusion: Laser ureteroscopy is an effective minimally invasive surgery in the management of lithiasis of the upper urinary tract. It significantly reduces the length of hospitalization. Mastery of this technique and the acquisition of the equipment necessary for its implementation is an undeniable asset in the management of renal and ureteral lithiasis. 展开更多
关键词 URETEROSCOPY SEMI-RIGID Flexible Holmium YAG Laser
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Effects of Crosswise Appendage Plate Flexibility on the Drag Reduction Characteristics of Cylinder
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作者 Jiyao Yang Xiaomei Ye +1 位作者 Guoyi He Feng Yu 《Journal of Applied Mathematics and Physics》 2024年第6期2032-2040,共9页
In engineering applications (Like an ocean riser), fluid flow around bluff bodies generates substantial resistance, which can jeopardize structural integrity, lifespan, and escalate resource consumption. Therefore, em... In engineering applications (Like an ocean riser), fluid flow around bluff bodies generates substantial resistance, which can jeopardize structural integrity, lifespan, and escalate resource consumption. Therefore, employing drag reduction measures becomes particularly crucial. This paper employs the immersed boundary method to investigate the impact of transversely oriented appendage plate flexibility on the drag of cylinders under different Reynolds numbers and distances. The results indicate that flexible appendage plate exerts drag reduction effects on the downstream cylinder, with this effect gradually diminishing as Reynolds numbers increase. At identical Reynolds numbers, the drag reduction effect initially increases and then decreases with distance, with the optimal drag reduction distance observed at D = 2.5. Compared to cylinders without appendage plate, the maximum drag reduction achieved is 30.551%. Addressing the drag reduction issue in cylinders holds significant importance for ensuring engineering structural integrity, enhancing engineering efficiency, and developing novel underwater towing systems. 展开更多
关键词 Appendage Plate flexibility Cylinder Flow Drag Reduction
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Ultrahigh thermoelectric properties of p‐type Bi_(x)Sb_(2−x)Te_(3) thin films with exceptional flexibility for wearable energy harvesting
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作者 Zhuang‐Hao Zheng Yi‐Ming Zhong +9 位作者 Yi‐Liu Li Mohammad Nisar Adil Mansoor Fu Li Shuo Chen Guang‐Xing Liang Ping Fan Dongyan Xu Meng Wei Yue‐Xing Chen 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期273-284,共12页
Use of a flexible thermoelectric source is a feasible approach to realizing selfpowered wearable electronics and the Internet of Things.Inorganic thin films are promising candidates for fabricating flexible power supp... Use of a flexible thermoelectric source is a feasible approach to realizing selfpowered wearable electronics and the Internet of Things.Inorganic thin films are promising candidates for fabricating flexible power supply,but obtaining highthermoelectric‐performance thin films remains a big challenge.In the present work,a p‐type Bi_(x)Sb_(2−x)Te_(3) thin film is designed with a high figure of merit of 1.11 at 393 K and exceptional flexibility(less than 5%increase in resistance after 1000 cycles of bending at a radius of∼5 mm).The favorable comprehensive performance of the Bi_(x)Sb_(2−x)Te_(3) flexible thin film is due to its excellent crystallinity,optimized carrier concentration,and low elastic modulus,which have been verified by experiments and theoretical calculations.Further,a flexible device is fabricated using the prepared p‐type Bi_(x)Sb_(2−x)Te_(3) and n‐type Ag_(2)Se thin films.Consequently,an outstanding power density of∼1028μWcm^(−2)is achieved at a temperature difference of 25 K.This work extends a novel concept to the fabrication of highperformance flexible thin films and devices for wearable energy harvesting. 展开更多
关键词 Bi_(x)Sb_(2−x)Te_(3) electrical transport properties flexibility theRMOELECTRIC
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Study on the Application Effect of Flexible Nursing Care in Patients with Postpartum Urinary Retention and its Effect on Lactation
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作者 Hongyan Zhu 《Journal of Clinical and Nursing Research》 2024年第4期122-127,共6页
Objective: To study the application effect of flexible nursing in patients with postpartum urinary retention and its effect on lactation. Methods: A total of 200 cases of postpartum urinary retention patients admitted... Objective: To study the application effect of flexible nursing in patients with postpartum urinary retention and its effect on lactation. Methods: A total of 200 cases of postpartum urinary retention patients admitted between January 2021 and January 2022 were selected and randomly grouped into two groups, a control group (conventional nursing) and an observation group (flexible nursing), of 100 cases each. The time of onset of lactation, the lactation volume score, urinary indicators, the amount of post-partum hemorrhage, and the quality of life score of the two groups were compared. Results: The observation group’s lactation initiation time (21.41 ± 1.52) h and lactation volume score (2.11 ± 0.52) were better than that of the control group (P < 0.05). The observation group’s first urination time (2.11 ± 0.51) min was lower than the control group, while the urinary retention completely relieved time (33.12 ± 8.61) h, and first urinary volume (262.17 ± 52.41) mL was higher than that of the control group (P < 0.05). The amount of postpartum hemorrhage in the observation group (151.21 ± 22.12) mL was less than that in the control group (P < 0.05). The scores of somatic functioning (86.25 ± 2.20), psychological functioning (91.56 ± 1.45), social functioning (89.25 ± 2.45), and material life (89.75 ± 1.45) of the observation group were higher than those of the control group after nursing (P < 0.05). Conclusion: Flexible nursing care in patients with postpartum urinary retention exhibited significant nursing effects and lactation function was effectively improved. 展开更多
关键词 Flexible nursing Postpartum urinary retention LACTATION
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Research on the Application of Second Language Acquisition Theory in College English Speech Teaching
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作者 Hui Zhang 《Journal of Contemporary Educational Research》 2024年第3期173-178,共6页
The teaching of English speeches in universities aims to enhance oral communication ability,improve English communication skills,and expand English knowledge,occupying a core position in English teaching in universiti... The teaching of English speeches in universities aims to enhance oral communication ability,improve English communication skills,and expand English knowledge,occupying a core position in English teaching in universities.This article takes the theory of second language acquisition as the background,analyzes the important role and value of this theory in English speech teaching in universities,and explores how to apply the theory of second language acquisition in English speech teaching in universities.It aims to strengthen the cultivation of English skilled talents and provide a brief reference for improving English speech teaching in universities. 展开更多
关键词 Second language acquisition theory Teaching English speeches in universities Practical strategies
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COMPRESSED SPEECH SIGNAL SENSING BASED ON THE STRUCTURED BLOCK SPARSITY WITH PARTIAL KNOWLEDGE OF SUPPORT 被引量:1
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作者 JiYunyun YangZhen XuQian 《Journal of Electronics(China)》 2012年第1期62-71,共10页
Structural and statistical characteristics of signals can improve the performance of Compressed Sensing (CS). Two kinds of features of Discrete Cosine Transform (DCT) coefficients of voiced speech signals are discusse... Structural and statistical characteristics of signals can improve the performance of Compressed Sensing (CS). Two kinds of features of Discrete Cosine Transform (DCT) coefficients of voiced speech signals are discussed in this paper. The first one is the block sparsity of DCT coefficients of voiced speech formulated from two different aspects which are the distribution of the DCT coefficients of voiced speech and the comparison of reconstruction performance between the mixed program and Basis Pursuit (BP). The block sparsity of DCT coefficients of voiced speech means that some algorithms of block-sparse CS can be used to improve the recovery performance of speech signals. It is proved by the simulation results of the mixed program which is an improved version of the mixed program. The second one is the well known large DCT coefficients of voiced speech focus on low frequency. In line with this feature, a special Gaussian and Partial Identity Joint (GPIJ) matrix is constructed as the sensing matrix for voiced speech signals. Simulation results show that the GPIJ matrix outperforms the classical Gaussian matrix for speech signals of male and female adults. 展开更多
关键词 Compressed Sensing (CS) speech signals Sensing matrix Block sparsity
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A Study on Parts of Speech Conversion in English and Chinese from the Perspective of Translation
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作者 陈志勇 《海外英语》 2016年第1期142-144,共3页
Parts of speech conversion refers to transforming the certain words of the source language into another category words of the target language, which is one of the common methods and techniques used in the translation ... Parts of speech conversion refers to transforming the certain words of the source language into another category words of the target language, which is one of the common methods and techniques used in the translation of English and Chinese languages. This paper starts from a relatively significant difference in English and Chinese language— the tendency of static words in English in contrast to that of dynamic words in Chinese, to explore the theoretical basis of transference in parts of speech in English and Chinese language translation. Combining with a large number of examples, the author puts forward some skills on transformation of parts of speech in English-Chinese translation to guide translation practice. The study found that the theoretical basis of the conversion in English and Chinese mostly including:1) there is a boundary ambiguity between lexical category;2)English SV/SVO structure is rigorous, which leads to expressing the dynamic meaning by means of using other lexical category; 3) the development of social culture not only makes new words continue to increase rapidly, but also gives many used words with new meanings; 4)it is acknowledged in Lexical morphology that English words which come from derivation are in larger number and derivations can make the word class of the corresponding original words either the same or different. The dynamic and specific features of Chinese make it more use of verbs in language use. Thus, in the process of translation, appropriate parts of speech conversion can make the translation more in line with their own habits of expression. 展开更多
关键词 partS of speech CONVERSION STATIC dynamic Chinese ENGLISH
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Enhancing the Efficiency of Voice Controlled Wheelchairs Using NAM for Recognizing Partial Speech in Tamil
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作者 Angappan Kumaresan Nagarajan Mohankumar +1 位作者 Mathavan Sureshanand Jothi Suganya 《Circuits and Systems》 2016年第10期2884-2892,共9页
In this paper, we have presented an effective method for recognizing partial speech with the help of Non Audible Murmur (NAM) microphone which is robust against noise. NAM is a kind of soft murmur that is so weak that... In this paper, we have presented an effective method for recognizing partial speech with the help of Non Audible Murmur (NAM) microphone which is robust against noise. NAM is a kind of soft murmur that is so weak that even people nearby the speaker cannot hear it. We can recognize this NAM from the mastoid of humans. It can be detected only with the help of a special type of microphone termed as NAM microphone. We can use this approach for impaired people who can hear sound but can speak only partial words (semi-mute) or incomplete words. We can record and recognize partial speech using NAM microphone. This approach can be used to solve problems for paralysed people who use voice controlled wheelchair which helps them to move around without the help of others. The present voice controlled wheelchair systems can recognize only fully spoken words and can’t recognise words spoken by semi-mute or partially speech impaired people. Further it uses normal microphone which hassevere degradation and external noise influence when used for recognizing partial speech inputs from impaired people. To overcome this problem, we can use NAM microphone along with Tamil Speech Recognition Engine (TSRE) to improve the accuracy of the results. The proposed method was designed and implemented in a wheelchair like model using Arduino microcontroller kit. Experimental results have shown that 80% accuracy can be obtained in this method and also proved that recognizing partially spoken words using NAM microphone was much efficient compared to the normal microphone. 展开更多
关键词 NAM speech Recognition TSRE Wheelchair Guidance HCI
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Experimental Georgian Speech Synthesizer Part 1 Structure of Synthesizer
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作者 Alexander Vashalomidze 《Journal of Mathematics and System Science》 2013年第6期289-300,共12页
The term "Experimental" in the title means, that the synthesizer is constructed as tool to conduct experiments, for investigating the influence of environment of unit on sounding of it. Synthesizer as tool for testi... The term "Experimental" in the title means, that the synthesizer is constructed as tool to conduct experiments, for investigating the influence of environment of unit on sounding of it. Synthesizer as tool for testing of hypotheses and results of experiments, satisfy three conditions: independence from the selection of unit for the synthesis (word or any part of it); taking into account the environment of unit (left and right hand contexts and position of unit); independence from the content of base. Such synthesizer is a good tool for studying many aspects of speech and removes the problem of selection. We can vary the unit and other parameters, described in paper, by the same synthesizer, synthesize the same text and listen to the results directly. This paper describes the formal structure of experimental Georgian speech synthesizer. 展开更多
关键词 speech synthesis interchangeable units adequate covering optimal covering.
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On the Conversion of Parts of Speech in English-Chinese Translation
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作者 侯丽香 张春艳 《海外英语》 2017年第19期147-149,共3页
Conversion refers to the transformation of parts of speech in some words while maintaining the original content unchanged in order to make the translated text sound smooth and fluent as well as more idiomatic in the t... Conversion refers to the transformation of parts of speech in some words while maintaining the original content unchanged in order to make the translated text sound smooth and fluent as well as more idiomatic in the target language. In E-C translation, conversion of pars of speech is one of the most important translation methods. Several different forms about conversion of parts of speech are introduced through analyzing the differences and usages between the two languages so that a better version in E-C translation can be got. 展开更多
关键词 E-C translation Conversion of parts of speech METHODS
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An Exploration of the Influences of a Third Party on Chinese College Students’Speech Act of Disagreement
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作者 刘颖 《海外英语》 2021年第12期105-107,共3页
Face is a concept much cared about and delicately disposed among Chinese people,especially with the presence of a third party.Unfortunately so far substantial studies on patterns and politeness strategies utilized to ... Face is a concept much cared about and delicately disposed among Chinese people,especially with the presence of a third party.Unfortunately so far substantial studies on patterns and politeness strategies utilized to diminish the threat to the inter-locutor's face in expressing disagreement have been carried out in English-as-the-first-language settings with lttle effort in ex-ploring disageement in Chinese culture.Therefore,this paper seeks to explore what disagreement strategies Chinese college stu-dents will use to mitigate the face-threatening act with absence or presence of a third party for an attempt to shed some light on the speech act theory in Chinese settings. 展开更多
关键词 disagreement strategies a third party speech act theory Chinese settings
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Enhancing the Interaction of Carbon Nanotubes by Metal-Organic Decomposition with Improved Mechanical Strength and Ultra-Broadband EMI Shielding Performance 被引量:3
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作者 Yu-Ying Shi Si-Yuan Liao +7 位作者 Qiao-Feng Wang Xin-Yun Xu Xiao-Yun Wang Xin-Yin Gu You-Gen Hu Peng-Li Zhu Rong Sun Yan-Jun Wan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期281-294,共14页
The remarkable properties of carbon nanotubes(CNTs)have led to promising applications in the field of electromagnetic inter-ference(EMI)shielding.However,for macroscopic CNT assemblies,such as CNT film,achieving high ... The remarkable properties of carbon nanotubes(CNTs)have led to promising applications in the field of electromagnetic inter-ference(EMI)shielding.However,for macroscopic CNT assemblies,such as CNT film,achieving high electrical and mechanical properties remains challenging,which heavily depends on the tube-tube interac-tions of CNTs.Herein,we develop a novel strategy based on metal-organic decomposition(MOD)to fabricate a flexible silver-carbon nanotube(Ag-CNT)film.The Ag particles are introduced in situ into the CNT film through annealing of MOD,leading to enhanced tube-tube interactions.As a result,the electrical conductivity of Ag-CNT film is up to 6.82×10^(5) S m^(-1),and the EMI shielding effectiveness of Ag-CNT film with a thickness of~7.8μm exceeds 66 dB in the ultra-broad frequency range(3-40 GHz).The tensile strength and Young’s modulus of Ag-CNT film increase from 30.09±3.14 to 76.06±6.20 MPa(~253%)and from 1.12±0.33 to 8.90±0.97 GPa(~795%),respectively.Moreover,the Ag-CNT film exhibits excellent near-field shield-ing performance,which can effectively block wireless transmission.This innovative approach provides an effective route to further apply macroscopic CNT assemblies to future portable and wearable electronic devices. 展开更多
关键词 EMI shielding Mechanical strength Carbon nanotubes Metal-organic decomposition flexibility
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An Analysis of the Hoarse Speech Signals by the Three Mass Model of Vocal Cords *
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作者 程启明 陈雪丽 万德钧 《Journal of Southeast University(English Edition)》 EI CAS 1998年第1期81-85,共5页
A three mass model of vocal cords as well as mathematical expression of the model are discussed. Different kinds of typical hoarse speech due to laryngeal diseases are simulated on microcomputer and the effects of di... A three mass model of vocal cords as well as mathematical expression of the model are discussed. Different kinds of typical hoarse speech due to laryngeal diseases are simulated on microcomputer and the effects of different pathological factors of vocal cords on model parameters are studied. Some typical spectrum distribution of the simulated speech signals are given. Moreover, hoarse speech signals of some typical cases are analyzed by the methods of digital signal processing, including FFT, LPC, Cepstrum technique, Pseudocolor encoding, etc. The experiment results show that the three mass model analysis of vocal cords is an efficient method for analysis of hoarse speech signals. 展开更多
关键词 hoarse speech signal three mass model of vocal cords laryngeal diseases
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Manipulating the Macroscopic and Microscopic Morphology of Large-Area Gravure-Printed ZnO Films for High-Performance Flexible Organic Solar Cells 被引量:1
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作者 Zhenguo Wang Jingbo Guo +6 位作者 Yaqin Pan Jin Fang Chao Gong Lixin Mo Qun Luo Jian Lin Changqi Ma 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期229-239,共11页
Gravure printing is a promising large-scale fabrication method for flexible organic solar cells(FOSCs)because it is compatible with two-dimension patternable roll-to-roll fabrication.However,the unsuitable rheological... Gravure printing is a promising large-scale fabrication method for flexible organic solar cells(FOSCs)because it is compatible with two-dimension patternable roll-to-roll fabrication.However,the unsuitable rheological property of ZnO nanoinks resulted in unevenness and looseness of the gravure-printed ZnO interfacial layer.Here we propose a strategy to manipulate the macroscopic and microscopic of the gravure-printed ZnO films through using mixed solvent and poly(vinylpyrrolidone)(PVP)additive.The regulation of drying speed effectively manipulates the droplets fusion and leveling process and eliminates the printing ribbing structure in the macroscopic morphology.The additive of PVP effectively regulates the rheological property and improves the microscopic compactness of the films.Following this method,large-area ZnO∶PVP films(28×9 cm^(2))with excellent uniformity,compactness,conductivity,and bending durability were fabricated.The power conversion efficiencies of FOSCs with gravure-printed AgNWs and ZnO∶PVP films reached 14.34%and 17.07%for the 1 cm^(2)PM6:Y6 and PM6∶L8-BO flexible devices.The efficiency of 17.07%is the highest value to date for the 1 cm^(2)FOSCs.The use of mixed solvent and PVP addition also significantly enlarged the printing window of ZnO ink,ensuring high-quality printed thin films with thicknesses varying from 30 to 100 nm. 展开更多
关键词 flexible organic solar cell gravure printing large-area flexible interfacial layer rheology properties zinc oxide
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An Analysis of the Language Features of Barack Obama's Inaugural Speeches
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作者 李红梅 吴丹 朱耀顺 《海外英语》 2014年第10X期258-259,264,共3页
This thesis tries to analyze the language features of Barack Obama's two inaugural speeches in 2008 and 2012 from the linguistic aspects,including sentence types as well as figures of speech which included imperat... This thesis tries to analyze the language features of Barack Obama's two inaugural speeches in 2008 and 2012 from the linguistic aspects,including sentence types as well as figures of speech which included imperative sentences,parallelism,rhetorical question,alliteration,hyperbole,simile,metaphor and so on. 展开更多
关键词 inaugural speech Barack OBAMA LANGUAGE FEATURES
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Probing the Linguistic and Rhetorical Features of English Speeches 被引量:1
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作者 李庆明 《西安理工大学学报》 CAS 2004年第3期327-331,共5页
English speech is a discourse delivered at an assembly or on formal occasions. As a variety of the English language, English speech has a unique presentation of its own. This paper, as its title indicates, is to analy... English speech is a discourse delivered at an assembly or on formal occasions. As a variety of the English language, English speech has a unique presentation of its own. This paper, as its title indicates, is to analyze and probe the linguistic and rhetorical features of famous English speeches with a view to improving the ability to appreciate English speeches on the part of Chinese learners of English. 展开更多
关键词 英语演讲 语言学 修辞特征 句型
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Traction power systems for electrified railways:evolution,state of the art,and future trends 被引量:1
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作者 Haitao Hu Yunjiang Liu +4 位作者 Yong Li Zhengyou He Shibin Gao Xiaojuan Zhu Haidong Tao 《Railway Engineering Science》 EI 2024年第1期1-19,共19页
Traction power systems(TPSs)play a vital role in the operation of electrified railways.The transformation of conventional railway TPSs to novel structures is not only a trend to promote the development of electrified ... Traction power systems(TPSs)play a vital role in the operation of electrified railways.The transformation of conventional railway TPSs to novel structures is not only a trend to promote the development of electrified railways toward high-efficiency and resilience but also an inevitable requirement to achieve carbon neutrality target.On the basis of sorting out the power supply structures of conventional AC and DC modes,this paper first reviews the characteristics of the existing TPSs,such as weak power supply flexibility and low-energy efficiency.Furthermore,the power supply structures of various TPSs for future electrified railways are described in detail,which satisfy longer distance,low-carbon,high-efficiency,high-reliability and high-quality power supply requirements.Meanwhile,the application prospects of different traction modes are discussed from both technical and economic aspects.Eventually,this paper introduces the research progress of mixed-system electrified railways and traction power supply technologies without catenary system,speculates on the future development trends and challenges of TPSs and predicts that TPSs will be based on the continuous power supply mode,employing power electronic equipment and intelligent information technology to construct a railway comprehensive energy system with renewable energy. 展开更多
关键词 Railway traction power system Future electrified railway Flexible continuous power supply Renewable energy Integrated energy system
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