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RESEARCH OF THE FEEDING SPEED ADOPTING CORED-WIRE METHOD TO SPHEROIDIZE DUCTILE IRON MELT 被引量:1
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作者 G.W. Chang H.X. Wang +1 位作者 X.D. Yue H.L. Zhang 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2008年第5期362-368,共7页
在把核心电线方法用于 spheroidize 为解决喂的问题加速可锻的铁融化, ANSYS 软件被使用模仿转移和质传,和在铁的钢长带的melt 时间融化的热被连接热转移和质传决定,然后喂的速度被计算。结论被得出了铁层在喂电线的过程期间在核心... 在把核心电线方法用于 spheroidize 为解决喂的问题加速可锻的铁融化, ANSYS 软件被使用模仿转移和质传,和在铁的钢长带的melt 时间融化的热被连接热转移和质传决定,然后喂的速度被计算。结论被得出了铁层在喂电线的过程期间在核心电线的表面上被形成。当时,厚度是 0.073 公里铁的温度融化是 1500 ° C,铁层的 remelting 的从形成的时间是 0.063 s。什么时候铁的温度融化在 1500 ° C 下面,花让钢长带融化的时间很快被弄短。什么时候铁的温度融化在 1500 ° C 上面,钢长带的变化振幅与时间融化变化逐渐地被减少。钢长带的 melt 时间很快随钢长带厚度的增加被增加。什么时候铁的温度融化是 1500 ° C,碳含量是 4% ,钢脱衣的 melt 时间,有 0.5 公里的厚度,是三次其厚度是 0.3 公里的钢脱衣的。喂的速度的计算结果是基本上在工厂里与使用的喂一致加速。 展开更多
关键词 延性铁 延期热处理 进给速度 数值模拟
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Attack-Resilient Distributed Cooperative Control of Virtually Coupled High-Speed Trains via Topology Reconfiguration
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作者 Shunyuan Xiao Xiaohua Ge Qing Wu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期1066-1068,共3页
Dear Editor,This letter addresses the resilient distributed cooperative control problem of a virtually coupled train convoy under stochastic disturbances and cyber attacks.The main purpose is to achieve distributed co... Dear Editor,This letter addresses the resilient distributed cooperative control problem of a virtually coupled train convoy under stochastic disturbances and cyber attacks.The main purpose is to achieve distributed coordination of virtually coupled high-speed trains with the prescribed inter-train distance and same cruise velocity. 展开更多
关键词 PRESCRIBED speed TRAINS
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Heart Failure-Like Reaction Is Likely Involved in the Feeding Behaviour of Blood-Sucking Leeches
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作者 Li Yang Jiao Shu +4 位作者 Xiao Wang Wei Yu Debin Wang Zichao Liu Bin Wang 《Advances in Bioscience and Biotechnology》 CAS 2024年第1期52-69,共18页
Medicinal leeches have been utilized in therapy for thousands of years. However, the adaptation physiology between leeches and hosts is not fully understand. To disclose the molecular mechanisms of adaptation between ... Medicinal leeches have been utilized in therapy for thousands of years. However, the adaptation physiology between leeches and hosts is not fully understand. To disclose the molecular mechanisms of adaptation between leech and host, the body transcriptomes of hunger and fed blood-sucking Poecilobdella javanica, Haemadipsa cavatuses, and Hirudo nipponia leeches were obtained by RNA sequencing, after comparison, a stratified unigenes group was obtained, which closely correlated to body distension. In the group, Rfamide receptor decreased significantly (P < 0.05) while serotonin receptor increased significantly (P < 0.05). Moreover, four KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways, including cardiac muscle contraction, complement and coagulation cascades, renin-angiotensin system, and hypertrophic cardiomyopathy were significantly enriched. The unigenes annotation, neuroregulators correlation analysis and induced function of the KEGG pathways, were consistently supported the same result as: vasoconstriction and systole reaction enhance in hunger leeches and vice versa vasodilation and diastole increase in fed leeches, meanwhile, Interspecific comparison and correlative analyses of physiological function showed that the strongest reaction of induced heart failure from four KEGG occur in strongest reaction of systole in hungry P. javanica and in strongest reaction of diastole in fed H. nipponia. Overall, heart failure is likely a physiological function involved in feeding behaviour. 展开更多
关键词 Blood-Sucking Leeches Transcriptomic Analysis Heart Failure feeding Behaviour
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Speed limit effect during lane change in a two-lane lattice model under V2X environment
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作者 金灿 彭光含 聂方彦 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期718-722,共5页
Speed limit measures are ubiquitous due to the complexity of the road environment,which can be supplied with the help of vehicle to everything(V2X)communication technology.Therefore,the influence of speed limit on tra... Speed limit measures are ubiquitous due to the complexity of the road environment,which can be supplied with the help of vehicle to everything(V2X)communication technology.Therefore,the influence of speed limit on traffic system will be investigated to construct a two-lane lattice model accounting for the speed limit effect during the lane change process under V2X environment.Accordingly,the stability condition and the mKdV equation are closely associated with the speed limit effect through theory analysis.Moreover,the evolution of density and hysteresis loop is simulated to demonstrate the positive role of the speed limit effect on traffic stability in the cases of strong reaction intensity and high limited speed. 展开更多
关键词 traffic flow lattice model speed limit
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The Development of a Feeding Coparenting Scale for Japanese Parents of Fifth- and Sixth-Grade Elementary School Children
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作者 Maiko Yasuzato Tae Kawahara +2 位作者 Yuichi Nakayama Cin Cin Tan Akemi Yamazaki 《Open Journal of Nursing》 2024年第1期27-39,共13页
Aim: Recently, the role of feeding coparenting has gained attention in the child eating research field. The Feeding Coparenting Scale (FCS), a measure of how caregivers interact with their partners when feeding their ... Aim: Recently, the role of feeding coparenting has gained attention in the child eating research field. The Feeding Coparenting Scale (FCS), a measure of how caregivers interact with their partners when feeding their children was developed in the United States in 2019. However, there is no valid and reliable measure to assess feeding coparenting among caregivers of school-aged children in Japan. Therefore, this study aimed to develop a Japanese version of the FCS (FCS-J) questionnaire for caregivers with school-aged children. Methods: This was a web-based cross-sectional survey completed by caregivers of children aged 10-12 years. A preliminary survey using interviews and a web-based survey was conducted and found that the translated items of the FCS into Japanese were understandable to Japanese people. The developed survey was administered to parents of children at an elementary school. The reliability of the survey was assessed using both test-retest reliability and internal consistency analysis. Exploratory factor analysis was used to test construct validity, and known population validity was examined in relation to attributes, marital satisfaction, and feeding tasks. Results: Findings with 135 parents of school-aged children showed good internal reliability and validity of the FCS-J. The mean score for the overall FCS-J score was 46.2 (SD = 6.2), with Cronbach’s α of 0.72. For the subscales, Cronbach’s α ranged from 0.75 to 0.79. In sum, the present study’s results support the three-factor structure of the FCS in Japanese caregivers in Japan. Conclusions: The developed FCS-J was found to have a certain degree of reliability and validity. In this study, a Japanese version of the FCS-J was developed. . 展开更多
关键词 CHILD Coparenting PARENTS feeding Coparenting
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Feeding Practices and Use of Lysine and Methionine in Pigrationing on Intensified Pig Breeding in the West Center and Hauts Bassins Regions of Burkina Faso
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作者 Isidor Zangbéwindin Ouedraogo Timbilfou Kiendrebeogo +1 位作者 Aboubacar Toguyeni Chantal Yvette Kabore-Zoungrana 《Open Journal of Animal Sciences》 2024年第1期23-38,共16页
The aim of the study was to assess feeding practices and the use of lysine and methionine in pig rationing on intensified and semi-intensive pig breeding in the Koudougou and Bobo-Dioulasso areas. To this end, a cross... The aim of the study was to assess feeding practices and the use of lysine and methionine in pig rationing on intensified and semi-intensive pig breeding in the Koudougou and Bobo-Dioulasso areas. To this end, a cross-sectional survey was carried out on 87 breeding in these towns. A Discriminant Factorial Analysis (DFA) confirming a k-means classification of the data collected was used to retain 71 breeding divided into three breeding classes: Class A (32.4% of breeding), Class B (14.08%) and Class C (53.52%). The results show that the majority of pig breeders were men between the ages of 36 and 59. Average herd sizes were 35 ± 28;79 ± 42 and 89 ± 21 pigs for Classes A, B and C respectively. The main breeds of pig found on the breeding were crossbred, Large white, local, Landrace and Duroc. Class A (26.1%), B (30%) and C (15.8%) breeders were familiar with both lysine and methionine. Class A breeders distributed feed staggered (65.2%) and in rations (34.8%). Lysine (13%) and methionine (8.7%) were purchased at 5250 FCFA/kg. Those in class B distributed feed staggered (50%) and in the form of rations (50%), in which they incorporated lysine (30%) and methionine (30%) purchased at a cost of 2500 FCFA/kg and 3000 FCFA/kg respectively. Rationing and staggered feeding were practiced by 23.7% and 76.3% of Class C breeders respectively. Only lysine purchased at 3400 FCFA/kg was incorporated into rations by 10.5% of breeders. The high cost of lysine and methionine was incriminated by Class A (100%), B (33.3%) and C (50%) breeders. In conclusion, intensive pig breeding, the practice of rationing and the incorporation of the amino acids lysine and methionine are of ascending importance from classes C, A to B. The high cost of feedstuffs, particularly lysine and methionine, compromises their use in rations, which could have a negative impact on expected breeding performance. The screening and use of feeds rich in and/or enriched with these amino acids, through the development or adaptation of technologies, could improve the efficiency of rations and the productivity of intensive pig breeding in Burkina Faso. 展开更多
关键词 feeding Practices LYSINE METHIONINE Intensive Pig Breeding Burkina Faso
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Early selective enteral feeding in treatment of acute pancreatitis: A case report
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作者 Aleksei A Kashintsev Sergey V Anisimov +1 位作者 Anastasya Nadeeva Vitali Proutski 《World Journal of Clinical Cases》 SCIE 2024年第3期637-642,共6页
BACKGROUND Early initiation of enteral feeding is recognized to play a crucial role in improving the outcomes of treatment of acute pancreatitis.However,the method of adminis-tration of enteral nutrition remains debat... BACKGROUND Early initiation of enteral feeding is recognized to play a crucial role in improving the outcomes of treatment of acute pancreatitis.However,the method of adminis-tration of enteral nutrition remains debatable.We present the experience of treating a patient with moderate-severe acute pancreatitis,at high risk of progressing to a severe or fatal condition,using a novel method of selective feeding with duodenal isolation.CASE SUMMARY A 27-year-old female patient presented to the emergency unit of the hospital with a typical manifestation of acute pancreatitis.Despite a conventional treatment,the patient’s condition deteriorated by day 2 of hospitalization.Using an endoscopic approach,a novel catheter PandiCathffwas placed to the duodenum of the patient,isolating its segment between the duodenal bulb and the ligament of Treitz.In the isolated area created,a negative pressure was applied,followed by introduction of early selective enteral feeding.The patient’s condition subsequently improved in a rapid manner,and no complications often associated with moderate-to-severe acute pancreatitis developed.CONCLUSION Within 48 h of starting treatment with the novel method,it can prevent the development of multiple organ failure and,when combined with minimally invasive drainage methods,help prevent infection. 展开更多
关键词 Acute pancreatitis Enteral feeding Infectious complications Systemic inflammatory response syndrome MODS
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Effects of wind speed,underlying surface,and seed morphological traits on the secondary seed dispersal in the Tengger Desert,China
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作者 QU Wenjie ZHAO Wenzhi +3 位作者 YANG Xinguo WANG Lei ZHANG Xue QU Jianjun 《Journal of Arid Land》 SCIE CSCD 2024年第4期531-549,共19页
The maintenance of sand-fixing vegetation is important for the stability of artificial sand-fixing systems in which seed dispersal plays a key role.Based on field wind tunnel experiments using 11 common plant species ... The maintenance of sand-fixing vegetation is important for the stability of artificial sand-fixing systems in which seed dispersal plays a key role.Based on field wind tunnel experiments using 11 common plant species on the southeastern edge of the Tengger Desert,China,we studied the secondary seed dispersal in the fixed and semi-fixed sand dunes as well as in the mobile dunes in order to understand the limitations of vegetation regeneration and the maintenance of its stability.Our results indicated that there were significant variations among the selected 11 plant species in the threshold of wind speed(TWS).The TWS of Caragana korshinskii was the highest among the 11 plant species,whereas that of Echinops gmelinii was the lowest.Seed morphological traits and underlying surface could generally explain the TWS.During the secondary seed dispersal processes,the proportions of seeds that did not disperse(no dispersal)and only dispersed over short distance(short-distance dispersal within the wind tunnel test section)were significantly higher than those of seeds that were buried(including lost seeds)and dispersed over long distance(long-distance dispersal beyond the wind tunnel test section).Compared with other habitats,the mobile dunes were the most difficult places for secondary seed dispersal.Buried seeds were the easiest to be found in the semi-fixed sand dunes,whereas fixed sand dunes were the best sites for seeds that dispersed over long distance.The results of linear mixed models showed that after controlling the dispersal distance,smaller and rounder seeds dispersed farther.Shape index and wind speed were the two significant influencing factors on the burial of seeds.The explanatory power of wind speed,underlying surface,and seed morphological traits on the seeds that did not disperse and dispersed over short distance was far greater than that on the seeds that were buried and dispersed over long distance,implying that the processes and mechanisms of burial and long-distance dispersal are more complex.In summary,most seeds in the study area either did not move,were buried,or dispersed over short distance,promoting local vegetation regeneration. 展开更多
关键词 seed dispersal seed morphological traits wind speed vegetation regeneration wind tunnel Tengger Desert
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Experimental study on the variation of optical remote sensing imaging characteristics of internal solitary waves with wind speed
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作者 Zhe CHANG Lina SUN +4 位作者 Tengfei LIU Meng ZHANG Keda LIANG Junmin MENG Jing WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期408-420,共13页
Optical remote sensing has been widely used to study internal solitary waves(ISWs).Wind speed has an important effect on ISW imaging of optical remote sensing.The light and dark bands of ISWs cannot be observed by opt... Optical remote sensing has been widely used to study internal solitary waves(ISWs).Wind speed has an important effect on ISW imaging of optical remote sensing.The light and dark bands of ISWs cannot be observed by optical remote sensing when the wind is too strong.The relationship between the characteristics of ISWs bands in optical remote sensing images and the wind speed is still unclear.The influence of wind speeds on the characteristics of the ISWs bands is investigated based on the physical simulation experiments with the wind speeds of 1.6,3.1,3.5,3.8,and 3.9 m/s.The experimental results show that when the wind speed is 3.9 m/s,the ISWs bands cannot be observed in optical remote sensing images with the stratification of h_(1)∶h_(2)=7∶58,ρ_(1)∶ρ_(2)=1∶1.04.When the wind speeds are 3.1,3.5,and 3.8 m/s,which is lower than 3.9 m/s,the ISWs bands can be obtained in the simulated optical remote sensing image.The location of the band’s dark and light extremum and the band’s peak-to-peak spacing are almost not affected by wind speed.More-significant wind speeds can cause a greater gray difference of the light-dark bands.This provided a scientific basis for further understanding of ISW optical remote sensing imaging. 展开更多
关键词 internal solitary wave(ISW) optical remote sensing wind speed characteristics of ISWs bands
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Corrosion Test of the Steel Plate in a WJ-8 Fastener for High Speed Rail
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作者 Zhiyong Wang Zhiping Zeng Hualiang (Harry) Teng 《Journal of Transportation Technologies》 2024年第1期16-30,共15页
It was found that the steel plate in the composite plate in the WJ-8 fastener used in high speed rail is rusty. The objective of this study is to test the zinc coating of the steel plate. A literature review was condu... It was found that the steel plate in the composite plate in the WJ-8 fastener used in high speed rail is rusty. The objective of this study is to test the zinc coating of the steel plate. A literature review was conducted to identify the zinc coating techniques, and the companies that can provide different coating service was identified. A salt fog chamber was built that was in compliance with the ANSI B117 code, and the steel plates that were coated by the identified companies were tested using the salt fog chamber. The results indicated that the coating technique that had the best performance in preventing corrosion was the Greenkote plates with passivation. The galvanized option had the roughest coating layer, and it was the most reactive in the salt water solution. This makes it non-ideal for the dynamic rail environment because the increased friction of the plate could damage the supports, especially during extreme temperatures that would cause the rail to expand or contract. Greenkote with Phosphate and ArmorGalv also provided increased corrosion prevention with a smooth, strong finish, but it had more rust on the surface area than the Greenkote with ELU passivation. The ArmorGalv sample had more rust on the surface area than the Greenkote samples. This may not be a weakness in the ArmorGalv process;rather, it likely was the result of this particular sample not having the added protection of a colored coating. 展开更多
关键词 Steel Plate for High speed Rail Fastening Steel Corrosion Zinc Coating Salt-Fog Chamber
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Determining future high speed rail review topics through bibliometric analysis
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作者 Heather Steele Marcelo Blumenfeld Paul Plummer 《High-Speed Railway》 2024年第1期17-29,共13页
As High Speed Rail(HSR)has proliferated globally,so has a related research field dedicated to exploring and addressing its unique issues.Yet,studies to understand and classify the HSR research domain are limited.This ... As High Speed Rail(HSR)has proliferated globally,so has a related research field dedicated to exploring and addressing its unique issues.Yet,studies to understand and classify the HSR research domain are limited.This paper addresses the gap,using bibliometric analysis to identify future research areas and 20 candidate topics for literature review based on keyword analysis through VOSviewer.Article and review papers related to HSR published in the last 20 years(2003-2022)were retrieved from Scopus,and then analyzed to determine the split in knowledge between languages,the collaboration between countries and institutions,highly productive and cited journals,and research topics which have and have not been reviewed.Approximately 30%of the search results were published exclusively in Chinese,highlighting the importance of extending the evaluation to cover both languages.This is a novel aspect of the work,which has enabled the recognition of potential knowledge gaps.It is recommended that future reviews incorporate works in both languages,possibly through international collaboration.Institutions in China and other countries that are strong collaborators have been identified,as well as relevant,highly cited journals. 展开更多
关键词 High speed rail Literature review Bibliometric analysis Vosviewer Keyword co-occurrence
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Numerical analysis of high‑speed railway slab tracks using calibrated and validated 3D time‑domain modelling
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作者 A.F.Esen O.Laghrouche +4 位作者 P.K.Woodward D.Medina‑Pineda Q.Corbisez J.Y.Shih D.P.Connolly 《Railway Engineering Science》 EI 2024年第1期36-58,共23页
Concrete slabs are widely used in modern railways to increase the inherent resilient quality of the tracks,provide safe and smooth rides,and reduce the maintenance frequency.In this paper,the elastic performance of a ... Concrete slabs are widely used in modern railways to increase the inherent resilient quality of the tracks,provide safe and smooth rides,and reduce the maintenance frequency.In this paper,the elastic performance of a novel slab trackform for high-speed railways is investigated using three-dimensional finite element modelling in Abaqus.It is then compared to the performance of a ballasted track.First,slab and ballasted track models are developed to replicate the full-scale testing of track sections.Once the models are calibrated with the experimental results,the novel slab model is developed and compared against the calibrated slab track results.The slab and ballasted track models are then extended to create linear dynamic models,considering the track geodynamics,and simulating train passages at various speeds,for which the Ledsgard documented case was used to validate the models.Trains travelling at low and high speeds are analysed to investigate the track deflections and the wave propagation in the soil,considering the issues associated with critical speeds.Various train loading methods are discussed,and the most practical approach is retained and described.Moreover,correlations are made between the geotechnical parameters of modern high-speed rail and conventional standards.It is found that considering the same ground condition,the slab track deflections are considerably smaller than those of the ballasted track at high speeds,while they show similar behaviour at low speeds. 展开更多
关键词 High-speed railways Slab track New ballastless track Ballasted track Critical speeds Finite element modelling Calibration of numerical models
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Key technologies of earthquake early warning system for China’s high-speed railway
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作者 Geming Zhang Lin Yang Wenxiang Jiang 《Railway Sciences》 2024年第2期239-262,共24页
Purpose–The purpose of this study is to introduce the top-level design ideas and the overall architecture of earthquake early-warning system for high speed railways in China,which is based on P-wave earthquake early-... Purpose–The purpose of this study is to introduce the top-level design ideas and the overall architecture of earthquake early-warning system for high speed railways in China,which is based on P-wave earthquake early-warning and multiple ways of rapid treatment.Design/methodology/approach–The paper describes the key technologies that are involved in the development of the system,such as P-wave identification and earthquake early-warning,multi-source seismic information fusion and earthquake emergency treatment technologies.The paper also presents the test results of the system,which show that it has complete functions and its major performance indicators meet the design requirements.Findings–The study demonstrates that the high speed railways earthquake early-warning system serves as an important technical tool for high speed railways to cope with the threat of earthquake to the operation safety.The key technical indicators of the system have excellent performance:The first report time of the P-wave is less than three seconds.From the first arrival of P-wave to the beginning of train braking,the total delay of onboard emergency treatment is 3.63 seconds under 95%probability.The average total delay for power failures triggered by substations is 3.3 seconds.Originality/value–The paper provides a valuable reference for the research and development of earthquake early-warning system for high speed railways in other countries and regions.It also contributes to the earthquake prevention and disaster reduction efforts. 展开更多
关键词 Earthquake early-warning High speed railway China earthquake networks center(CENC) Earthquake emergency treatment
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Roller Screw and Threaded Chain Speed Reducer: An Experimental Evaluation
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作者 Filiberto Gutiérrez 《Modern Mechanical Engineering》 2024年第1期1-11,共11页
We are developing a speed reducer that can be considered a transformation of a worm gear reducer: the worm is replaced by an inverted roller screw, and the gear is replaced by a threaded chain drive. This configuratio... We are developing a speed reducer that can be considered a transformation of a worm gear reducer: the worm is replaced by an inverted roller screw, and the gear is replaced by a threaded chain drive. This configuration lessens wear, increases load capacity, and improves efficiency. The threaded chain consists of nut-shaped links. This paper presents the results of tests carried out on a prototype with a reduction ratio of 46. 展开更多
关键词 speed Reducer Inverted Roller Screw Chain Drive Threaded Chain Drive
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A Method to Obtain the Moving Speed of Uncooperative Target Based on Only Two Measurements
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作者 Tao Yu 《Advances in Aerospace Science and Technology》 2024年第1期1-9,共9页
The existing research results show that a fixed single station must conduct three consecutive frequency shift measurements and obtain the target’s moving speed by constructing two frequency difference equations. This... The existing research results show that a fixed single station must conduct three consecutive frequency shift measurements and obtain the target’s moving speed by constructing two frequency difference equations. This article proposes a new method that requires only two consecutive measurements. While using the azimuth measurement to obtain the angular difference between two radial distances, it also conducts two consecutive Doppler frequency shift measurements at the same target azimuth. On the basis of this measurement, a frequency difference equation is first constructed and solved jointly with the Doppler frequency shift equation. By eliminating the velocity variable and using the measured angular difference to obtain the target’s lead angle, the target’s velocity can be solved by using the Doppler frequency shift equation again. The new method avoids the condition that the target must move equidistantly, which not only provides an achievable method for engineering applications but also lays a good foundation for further exploring the use of steady-state signals to achieve passive positioning. 展开更多
关键词 Moving speed Non-Cooperative Target Doppler Frequency Shift Frequency Difference Equation AZIMUTH Steady-State Signal Passive Location
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Wind Speed Prediction Based on Improved VMD-BP-CNN-LSTM Model
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作者 Chaoming Shu Bin Qin Xin Wang 《Journal of Power and Energy Engineering》 2024年第1期29-43,共15页
Amid the randomness and volatility of wind speed, an improved VMD-BP-CNN-LSTM model for short-term wind speed prediction was proposed to assist in power system planning and operation in this paper. Firstly, the wind s... Amid the randomness and volatility of wind speed, an improved VMD-BP-CNN-LSTM model for short-term wind speed prediction was proposed to assist in power system planning and operation in this paper. Firstly, the wind speed time series data was processed using Variational Mode Decomposition (VMD) to obtain multiple frequency components. Then, each individual frequency component was channeled into a combined prediction framework consisting of BP neural network (BPNN), Convolutional Neural Network (CNN) and Long Short-Term Memory Network (LSTM) after the execution of differential and normalization operations. Thereafter, the predictive outputs for each component underwent integration through a fully-connected neural architecture for data fusion processing, resulting in the final prediction. The VMD decomposition technique was introduced in a generalized CNN-LSTM prediction model;a BPNN model was utilized to predict high-frequency components obtained from VMD, and incorporated a fully connected neural network for data fusion of individual component predictions. Experimental results demonstrated that the proposed improved VMD-BP-CNN-LSTM model outperformed other combined prediction models in terms of prediction accuracy, providing a solid foundation for optimizing the safe operation of wind farms. 展开更多
关键词 Wind speed Forecast Long Short-Term Memory Network BP Neural Network Variational Mode Decomposition Data Fusion
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关节镜下speed-bridge技术修复中大型肩袖撕裂的临床应用
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作者 季斌 樊珂良 +5 位作者 陆超峰 刘磊 年坤党 方志豪 游镇君 吴可沁 《全科医学临床与教育》 2024年第1期28-31,共4页
目的 探讨关节镜下speed-bridge技术修复中大型肩袖撕裂的临床应用效果。方法 回顾性选择18例中大型肩袖撕裂的患者,均采用关节镜下speed-bridge技术修复肩袖撕裂,术后指导康复锻炼。记录患者术前、术后1个月、术后3个月和术后6个月的... 目的 探讨关节镜下speed-bridge技术修复中大型肩袖撕裂的临床应用效果。方法 回顾性选择18例中大型肩袖撕裂的患者,均采用关节镜下speed-bridge技术修复肩袖撕裂,术后指导康复锻炼。记录患者术前、术后1个月、术后3个月和术后6个月的肩关节前屈及外展活动度、疼痛视觉模拟评分(VAS)、Constant-Murley肩关节功能评分。结果 术前、术后1个月、术后3个月、术后6个月患者肩关节前屈活动度分别为(83.33±3.75)°、(98.06±3.12)°、(120.00±2.49)°、(139.72±2.74)°;肩关节外展活动度分别为(69.17±4.40)°、(82.50±4.24)°、(111.39±3.19)°、(138.89±2.74)°;VAS评分分别为(5.78±0.30)分、(3.28±0.22)分、(2.06±0.25)分、(0.89±0.17)分;Constant-Murley评分分别为(53.17±1.15)分、(60.33±1.07)分、(71.61±1.11)分、(80.83±0.91)分。术后随着康复锻炼的进行,肩关节前屈及外展活动度、VAS评分、Constant-Murley肩关节功能评分均明显改善,差异均有统计学意义(P<0.05)。结论 采用关节镜下speed-bridge技术修复中大型肩袖撕裂,操作简便,并发症少,可取得满意疗效。 展开更多
关键词 speed-bridge 无结缝线桥技术 中大型肩袖撕裂 疗效
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Precise Positioning Method for Seafloor Geodetic Stations Based on the Temporal Variation of Sound Speed Structure 被引量:1
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作者 Shuang ZHAO Zhenjie WANG +3 位作者 Zhixi NIE Kaifei HE Huimin LIU Zhen SUN 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第2期81-92,共12页
At present,GNSS-Acoustic(GNSS-A)combined technology is widely used in positioning for seafloor geodetic stations.Based on Sound Velocity Profiles(SVPs)data,the equal gradient acoustic ray-tracing method is applied in ... At present,GNSS-Acoustic(GNSS-A)combined technology is widely used in positioning for seafloor geodetic stations.Based on Sound Velocity Profiles(SVPs)data,the equal gradient acoustic ray-tracing method is applied in high-precision position inversion.However,because of the discreteness of the SVPs used in the forementioned method,it ignores the continuous variation of sound velocity structure in time domain,which worsens the positioning accuracy.In this study,the time-domain variation of Sound Speed Structure(SSS)has been considered,and the cubic B-spline function is applied to characterize the perturbed sound velocity.Based on the ray-tracing theory,an inversion model of“stepwise iteration&progressive corrections”for both positioning and sound speed information is proposed,which conducts the gradual correction of seafloor geodetic station coordinates and disturbed sound velocity.The practical data was used to test the effectiveness of our method.The results show that the Root Mean Square(RMS)errors of the residual values of the traditional methods without sound velocity correction,based on quadratic polynomial correction and based on cubic B-spline function correction are 1.43 ms,0.44 ms and 0.21 ms,respectively.The inversion model with sound velocity correction can effectively eliminate the systematic error caused by the change of SSS,and significantly improve the positioning accuracy of the seafloor geodetic stations. 展开更多
关键词 GNSS-Acoustic sound speed structure temporal variation seafloor positioning
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Adaptive Fault Estimation for Dynamics of High Speed Train Based on Robust UKF Algorithm 被引量:1
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作者 Kexin Li Tiantian Liang 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第1期61-72,共12页
This paper proposes an adaptive unscented Kalman filter algorithm(ARUKF)to implement fault estimation for the dynamics of high⁃speed train(HST)with measurement uncertainty and time⁃varying noise with unknown statistic... This paper proposes an adaptive unscented Kalman filter algorithm(ARUKF)to implement fault estimation for the dynamics of high⁃speed train(HST)with measurement uncertainty and time⁃varying noise with unknown statistics.Firstly,regarding the actuator and sensor fault as the auxiliary variables of the dynamics of HST,an augmented system is established,and the fault estimation problem for dynamics of HST is formulated as the state estimation of the augmented system.Then,considering the measurement uncertainties,a robust lower bound is proposed to modify the update of the UKF to decrease the influence of measurement uncertainty on the filtering accuracy.Further,considering the unknown time⁃varying noise of the dynamics of HST,an adaptive UKF algorithm based on moving window is proposed to estimate the time⁃varying noise so that accurate concurrent actuator and sensor fault estimations of dynamics of HST is implemented.Finally,a five-car model of HST is given to show the effectiveness of this method. 展开更多
关键词 high speed train Kalman filter adaptive algorithm robust algorithm unknown noise measurement uncertainty
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Deep Learning for Wind Speed Forecasting Using Bi-LSTM with Selected Features 被引量:1
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作者 Siva Sankari Subbiah Senthil Kumar Paramasivan +2 位作者 Karmel Arockiasamy Saminathan Senthivel Muthamilselvan Thangavel 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期3829-3844,共16页
Wind speed forecasting is important for wind energy forecasting.In the modern era,the increase in energy demand can be managed effectively by fore-casting the wind speed accurately.The main objective of this research ... Wind speed forecasting is important for wind energy forecasting.In the modern era,the increase in energy demand can be managed effectively by fore-casting the wind speed accurately.The main objective of this research is to improve the performance of wind speed forecasting by handling uncertainty,the curse of dimensionality,overfitting and non-linearity issues.The curse of dimensionality and overfitting issues are handled by using Boruta feature selec-tion.The uncertainty and the non-linearity issues are addressed by using the deep learning based Bi-directional Long Short Term Memory(Bi-LSTM).In this paper,Bi-LSTM with Boruta feature selection named BFS-Bi-LSTM is proposed to improve the performance of wind speed forecasting.The model identifies relevant features for wind speed forecasting from the meteorological features using Boruta wrapper feature selection(BFS).Followed by Bi-LSTM predicts the wind speed by considering the wind speed from the past and future time steps.The proposed BFS-Bi-LSTM model is compared against Multilayer perceptron(MLP),MLP with Boruta(BFS-MLP),Long Short Term Memory(LSTM),LSTM with Boruta(BFS-LSTM)and Bi-LSTM in terms of Root Mean Square Error(RMSE),Mean Absolute Error(MAE),Mean Square Error(MSE)and R2.The BFS-Bi-LSTM surpassed other models by producing RMSE of 0.784,MAE of 0.530,MSE of 0.615 and R2 of 0.8766.The experimental result shows that the BFS-Bi-LSTM produced better forecasting results compared to others. 展开更多
关键词 Bi-directional long short term memory boruta feature selection deep learning machine learning wind speed forecasting
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