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Multi-class classification method for strip steel surface defects based on support vector machine with adjustable hyper-sphere 被引量:2
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作者 Mao-xiang Chu Xiao-ping Liu +1 位作者 Rong-fen Gong Jie Zhao 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2018年第7期706-716,共11页
Focusing on strip steel surface defects classification, a novel support vector machine with adjustable hyper-sphere (AHSVM) is formulated. Meanwhile, a new multi-class classification method is proposed. Originated f... Focusing on strip steel surface defects classification, a novel support vector machine with adjustable hyper-sphere (AHSVM) is formulated. Meanwhile, a new multi-class classification method is proposed. Originated from support vector data description, AHSVM adopts hyper-sphere to solve classification problem. AHSVM can obey two principles: the margin maximization and inner-class dispersion minimization. Moreover, the hyper-sphere of AHSVM is adjustable, which makes the final classification hyper-sphere optimal for training dataset. On the other hand, AHSVM is combined with binary tree to solve multi-class classification for steel surface defects. A scheme of samples pruning in mapped feature space is provided, which can reduce the number of training samples under the premise of classification accuracy, resulting in the improvements of classification speed. Finally, some testing experiments are done for eight types of strip steel surface defects. Experimental results show that multi-class AHSVM classifier exhibits satisfactory results in classification accuracy and efficiency. 展开更多
关键词 Strip steel surface defect Multi-class classification Supporting vector machine adjustable hyper-sphere
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Continuously adjustable mechanical metamaterial based on planetary gear trains and external meshing gears
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作者 Shuai MO Xu TANG +2 位作者 Keren CHEN H.HOUJOH Wei ZHANG 《Applied Mathematics and Mechanics(English Edition)》 2025年第2期233-252,共20页
The metamaterial based on external meshing gears(MEG)is designed based on the principle of external meshing gear transmission.Based on the meshing transmission principle of external meshing gears and planetary gear tr... The metamaterial based on external meshing gears(MEG)is designed based on the principle of external meshing gear transmission.Based on the meshing transmission principle of external meshing gears and planetary gear trains,the internal and external gear rings are designed.Based on the internal and external gear rings,the metamaterial based on inner and outer planetary gear trains(MIP)is designed to study the shear modulus,Young's modulus,and amplitude-frequency characteristics of the metamaterial based on gears at different angles.The effects of the number of planetary gears on the physical characteristics of the MIP are studied.The results show that the MEG can be continuously adjusted by adjusting the shear modulus and Young's modulus due to its meshing characteristics.With the same number of gears,the adjustment range of the MIP is larger than the adjustment range of the MEG.When the number of planetary gears increases,the adjustment range of the MIP decreases.Moreover,when the metamaterial based on gears rotates,the harmonic response changes with the change of the angle. 展开更多
关键词 METAMATERIAL adjustable EXTERNAL inner and outer planetary gear train
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Design and Application of Quantitative Adjustable Liquid Injection Device for Maize Stalk Center Borehole
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作者 Yan YE 《Asian Agricultural Research》 2025年第2期41-44,共4页
In view of the problems that the drilling depth can not be adjusted and the amount of liquid injection can not be accurately modulated in the local test device of maize variety breeding and disease resistance,combinin... In view of the problems that the drilling depth can not be adjusted and the amount of liquid injection can not be accurately modulated in the local test device of maize variety breeding and disease resistance,combining the test technical requirements of drilling,liquid injection and sealing of the penultimate radial pitch of maize straw from the ground,a quantitative adjustable liquid injection device for maize stalk center borehole was designed.Its structure,working principle,key technical parameters and practical application effect were elaborated in detail.The field experiment demonstrated that the quantitative adjustable liquid injection device for maize stalk center borehole could meet the requirements of the local test of maize stalk rot. 展开更多
关键词 Maize stalk Center borehole Quantitative adjustable liquid injection
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Adjustable random linear network coding(ARLNC): A solution for data transmission in dynamic IoT computational environments
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作者 Raffi Dilanchian Ali Bohlooli Kamal Jamshidi 《Digital Communications and Networks》 2025年第2期574-586,共13页
In mobile computing environments, most IoT devices connected to networks experience variable error rates and possess limited bandwidth. The conventional method of retransmitting lost information during transmission, c... In mobile computing environments, most IoT devices connected to networks experience variable error rates and possess limited bandwidth. The conventional method of retransmitting lost information during transmission, commonly used in data transmission protocols, increases transmission delay and consumes excessive bandwidth. To overcome this issue, forward error correction techniques, e.g., Random Linear Network Coding(RLNC) can be used in data transmission. The primary challenge in RLNC-based methodologies is sustaining a consistent coding ratio during data transmission, leading to notable bandwidth usage and transmission delay in dynamic network conditions. Therefore, this study proposes a new block-based RLNC strategy known as Adjustable RLNC(ARLNC), which dynamically adjusts the coding ratio and transmission window during runtime based on the estimated network error rate calculated via receiver feedback. The calculations in this approach are performed using a Galois field with the order of 256. Furthermore, we assessed ARLNC's performance by subjecting it to various error models such as Gilbert Elliott, exponential, and constant rates and compared it with the standard RLNC. The results show that dynamically adjusting the coding ratio and transmission window size based on network conditions significantly enhances network throughput and reduces total transmission delay in most scenarios. In contrast to the conventional RLNC method employing a fixed coding ratio, the presented approach has demonstrated significant enhancements, resulting in a 73% decrease in transmission delay and a 4 times augmentation in throughput. However, in dynamic computational environments, ARLNC generally incurs higher computational costs than the standard RLNC but excels in high-performance networks. 展开更多
关键词 Random linear network coding adjust redundancy Galois field Internet of Things Data transfer
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Risk adjustable optimal operation for electricity-hydrogen integrated energy system based on chance constrained goal programming
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作者 ZHOU Xiao-jun HU Jia-ming +1 位作者 LI Chao-jie YANG Chun-hua 《Journal of Central South University》 2025年第6期2224-2238,共15页
The electricity-hydrogen integrated energy system(EH-IES)enables synergistic operation of electricity,heat,and hydrogen subsystems,supporting renewable energy integration and efficient multi-energy utilization in futu... The electricity-hydrogen integrated energy system(EH-IES)enables synergistic operation of electricity,heat,and hydrogen subsystems,supporting renewable energy integration and efficient multi-energy utilization in future low carbon societies.However,uncertainties from renewable energy and load variability threaten system safety and economy.Conventional chance-constrained programming(CCP)ensures reliable operation by limiting risk.However,increasing source-load uncertainties that can render CCP models infeasible and exacerbate operational risks.To address this,this paper proposes a risk-adjustable chance-constrained goal programming(RACCGP)model,integrating CCP and goal programming to balance risk and cost based on system risk assessment.An intelligent nonlinear goal programming method based on the state transition algorithm(STA)is developed,along with an improved discretized step transformation,to handle model nonlinearity and enhance computational efficiency.Experimental results show that the proposed model reduces costs while controlling risk compared to traditional CCP,and the solution method outperforms average sample sampling in efficiency and solution quality. 展开更多
关键词 electricity-hydrogen integrated energy system chance constrained goal programming risk adjustment state transition algorithm
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INTERVAL ADJUSTABLE ENTROPY ALGORITHM FOR A CLASS OF UNCONSTRAINED DISCRETE MINIMAX PROBLEMS 被引量:6
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作者 LiSubei CaoDexin +1 位作者 WangHaijun DengKazhong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2004年第1期37-43,共7页
In this paper,a class of unconstrained discrete minimax problems is described,in which the objective functions are in C 1.The paper deals with this problem by means of taking the place of maximum entropy function... In this paper,a class of unconstrained discrete minimax problems is described,in which the objective functions are in C 1.The paper deals with this problem by means of taking the place of maximum entropy function with adjustable entropy function.By constructing an interval extension of adjustable entropy function an d some region deletion test rules,a new interval algorithm is presented.The rele vant properties are proven.The minimax value and the localization of the minimax points of the problem can be obtained by this method. This method can overcome the flow problem in the maximum entropy algorithm.Both theoretical and numerica l results show that the method is reliable and efficient. 展开更多
关键词 discrete minimax problem adjustable entropy function interval algorithm .
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Design method of organizational structure for MAVs and UAVs heterogeneous team with adjustable autonomy 被引量:7
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作者 CHEN Jun QIU Xunjie +1 位作者 RONG Jia GAO Xiaoguang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第2期286-295,共10页
The increasingly complex battlefield environment requests much closer connection in a team having both manned and unmanned aerial vehicles(MAVs and UAVs). This special heterogeneous team structure causes demands for e... The increasingly complex battlefield environment requests much closer connection in a team having both manned and unmanned aerial vehicles(MAVs and UAVs). This special heterogeneous team structure causes demands for effective organizational structure design solutions. Implementing adjustable autonomy in the organizational structure, the expected evaluation function is established based on the physical resource, intelligent resource, network efficiency, network vulnerability and task execution reliability. According to the above constraints, together with interaction latency, decision-making information processing capacity, and decision-making latency, we aim to find a preferential organizational structure. The proposed organizational structure includes cooperative relationships, supervisory control relationships, and decision-making authorization relationships. In addition,by considering the influence on the intelligent support capabilities and the task execution reliability created by adjustable autonomy, it helps to build the proposed organizational structure designed with certain degree of flexibility to deal with the potential changes in the unpredictable battlefield environment. Simulation is conducted to confirm our design to be valid. And the method is still valid under different battlefield environments and interventions. 展开更多
关键词 organizational structure cooperative relationship supervisory control relationship decision-making authorization relationship adjustable autonomy
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Effectivity of intraoperative adjustable suture technique in horizontal strabismus 被引量:3
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作者 Ayse Gul Kocak Altintas Hasan Basri Arifoglu +2 位作者 Inci Kocak Midillioglu Elif Damar Gungor Saban Simsek 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2013年第4期492-497,共6页
AIMTo compare the long-term effectivity of intraoperative adjustable suture technique with traditional non-adjustable strabismus surgery.
关键词 adjustable suture strabismus surgery esodeviation exodeviation
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Adjustable entropy function method for support vector machine 被引量:4
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作者 Wu Qing Liu Sanyang Zhang Leyou 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第5期1029-1034,共6页
Based on KKT complementary condition in optimization theory, an unconstrained non-differential optimization model for support vector machine is proposed. An adjustable entropy function method is given to deal with the... Based on KKT complementary condition in optimization theory, an unconstrained non-differential optimization model for support vector machine is proposed. An adjustable entropy function method is given to deal with the proposed optimization problem and the Newton algorithm is used to figure out the optimal solution. The proposed method can find an optimal solution with a relatively small parameter p, which avoids the numerical overflow in the traditional entropy function methods. It is a new approach to solve support vector machine. The theoretical analysis and experimental results illustrate the feasibility and efficiency of the proposed algorithm. 展开更多
关键词 OPTIMIZATION support vector machine adjustable entropy function Newton algorithm.
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Velocity adjustable TMD and numerical simulation of seismic performance 被引量:4
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作者 秦丽 周锡元 闫维明 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2007年第2期147-158,共12页
A new type of velocity adjustable tuned mass damper (TMD) consisting of impulse generators and clutches is presented. The force impulse is generated by a joining operation of electromagnets and springs and MR damper... A new type of velocity adjustable tuned mass damper (TMD) consisting of impulse generators and clutches is presented. The force impulse is generated by a joining operation of electromagnets and springs and MR dampers are used as clutches. Rules for velocity adjustment are established according to the working mechanism of TMD. The analysis program is developed on a VB platform. Seismic response of SDOF structures with both passive TMD and velocity adjustable TMD are analyzed. The results show that (l) the control effectiveness of passive TMDs is usually unstable; (2) the control effectiveness of the proposed semi-active TMDs is much better than passive TMDs under typical seismic ground motions; and (3) unlike the passive TMD system, the proposed velocity adjustable TMDs exhibit good control effectiveness even when the primary structure performance becomes inelastic during severe earthquakes. 展开更多
关键词 velocity adjustable TMD passive TMDs MR damper seismic control control effectiveness
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Bowel perforation due to break and distal passage of the safety ring of an adjustable intra-gastric balloon: A potentially life threatening situation 被引量:3
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作者 Ali M Al-Zubaidi Hassan U Alghamdi +2 位作者 Abdu H Alzobydi Irshad A Dhiloon Laeeque A Qureshi 《World Journal of Gastrointestinal Endoscopy》 CAS 2015年第4期429-432,共4页
A 45-year-old man of Middle Eastern origin, morbid obese, with a body mass index of 39 had an intragastric balloon, filled with 500 mL of saline/methylene blue and intended as definite therapy, inserted some8 wk previ... A 45-year-old man of Middle Eastern origin, morbid obese, with a body mass index of 39 had an intragastric balloon, filled with 500 mL of saline/methylene blue and intended as definite therapy, inserted some8 wk previously. He was admitted to the emergency department with abdominal cramps. An ultrasound of the abdomen was performed in ER which confirmed the balloon to be in place without any abnormality.He was discharged home on symptomatic medication.Patient remains symptomatic therefore he reported back to ER 2 d later. Computed tomography scan was performed this time for further evaluation which revealed a metallic ring present in the small bowel while the intra-gastric balloon was in its proper position.There was no clinical or radiological sign of intestinal obstruction. Patient was hospitalized for observation and conservative management. The following night,patient experienced sudden and severe abdominal pain, therefore an X-ray of the abdomen in erect position was done, which showed free air under the right dome of diaphragm. Patient was transferred to O.R for emergency laparotomy. There were two small perforations identified at the site of the metallic ring entrapment. The ring was removed and the perforations were repaired. Due to increasing prevalence of obesity and advances in modalities for its management,physicians should be aware of treatment options, their benefits, complications and clinical presentation of the known complications. Physicians need to be updated to approach these complications within time, to avoid lifethreatening situations caused by these appliances. 展开更多
关键词 Spatz adjustable balloon Intragastricballoon MORBID obesity SAFETY RING PERFORATION
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Simulator of pyroshock environment and effect rules of its adjustable parameters 被引量:3
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作者 Hongda ZHAO Jifeng DING +4 位作者 Wei LIU Zhiwei HAO Yi SUN Qiuhua ZHANG Yizhi LIU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第2期609-620,共12页
During the launching of spacecraft,the on-board devices will undergo a series of pyroshock environments.In order to verify the reliability of these devices under these pyroshock environments,all of them are needed to ... During the launching of spacecraft,the on-board devices will undergo a series of pyroshock environments.In order to verify the reliability of these devices under these pyroshock environments,all of them are needed to take the shock test before launching.This paper has carried out an in-depth research on the simulation method of the pyroshock based on the true explosive excitation.In this study,a simulator containing multiple adjustment parameters is presented and the safety is considered by the design of the protective cover.And the working process of this setup is simulated with the explicit dynamic codes LS-DYNA.Whafs more,the effects of the adjustment parameters on the three factors of shock Response Spectrum(SRS)of the resonant board are explored carefully.The rules achieved in this paper are verified by a typical example.The results indicate that the improved simulator can avoid the danger of explosive and make full use of the advantage of actual explosive excitation.And the test condition can be quickly realized at the simulator according to the effect rules of the three adjustable parameters. 展开更多
关键词 adjustable parameters Maximum EXPECTED FLIGHT Environment(MEFE) Protective COVER Pyroshock Shock Response Spectrum(SRS)
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Adjustable Luminescence of SrAl_2O_4:Eu^(2+),Dy ^(3+) Assembled in Zeolite 被引量:1
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作者 刘应亮 王晓华 +3 位作者 张静娴 容建华 黄浪欢 袁定胜 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第1期100-103,共4页
Capsulating vip into the nanometer voids of zeolites is a effective way to form novel host-vip material. In our work, stoichiometric SrAl2O4 : Eu2+, Dy3+ sol vip was prepared by sol-gel method and assembled into... Capsulating vip into the nanometer voids of zeolites is a effective way to form novel host-vip material. In our work, stoichiometric SrAl2O4 : Eu2+, Dy3+ sol vip was prepared by sol-gel method and assembled into the nanometer channels of zeolite ZSM-5 host through mechanical mixing, hydrothemial reaction and microwave heating reaction, respectively. After being reduced and diffused in a microwave muffle, the fluorescence spectra of the host-vip materials exhibit remarkable blue shifts in companison of that of SrAl2O4 : Eu2+, Dy3+ Some interesting phenomena in the assembled host-vip materials are that the after-low emission spectra exist two bands at about 400 nm and 517 nm and the relative strengths of these two hands can be adjusted by changing the assembly methods and the assembly concentration. These are attributed to the fact that the phosphor was capsuiated into the voids of zeolite ZSM-5 and generated the quantum size effect and the host-vip effect. 展开更多
关键词 ZEOLITE ASSEMBLE blue shift adjustable PHOSPHORESCENCE rare earths
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Astigmatic correction with implantation of a light adjustable vs monofocal lens:a single site analysis of a randomized controlled trial 被引量:4
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作者 Majid Moshirfar William D.Wagner +6 位作者 Steven H.Linn David F.Skanchy Tanner W.Brown Aaron T.Gomez Jackson L.Goldberg Yasmyne C.Ronquillo Phillip C.Hoopes Jr. 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第7期1101-1107,共7页
AIM:To evaluate the light adjustable lens(LAL)vs a standard monofocal lens in achieving target astigmatic refraction and improving postoperative uncorrected distance visual acuity(UDVA).METHODS:This randomized control... AIM:To evaluate the light adjustable lens(LAL)vs a standard monofocal lens in achieving target astigmatic refraction and improving postoperative uncorrected distance visual acuity(UDVA).METHODS:This randomized controlled clinical trial included 40 patients with pre-existing astigmatism and visually significant cataract.Twenty-eight patients received the LAL and 12 control patients received a monofocal intraocular lens(IOL)after cataract extraction at a single institution.The patients with the LAL underwent adjustment by ultraviolet(UV)light postoperatively plus subsequent lock-in procedures and all patients returned to clinic for follow up of study parameters at 6,9,and 12 mo.Manifest refraction,distance visual acuity,and adverse events were recorded at each visit.RESULTS:The mean cylinder before adjustment in eyes with the LAL was-0.89±0.58 D(-2.00 to 0.00 D)and-0.34±0.34 D(-1.25 to 0.00 D)after lock-in(P=1.68 x10-8).The mean cylinder in patients with the monofocal lens was-1.00±0.32 D(-1.50 to-0.50 D)at 17-21 d postoperatively,which was statistically different from the LAL cylinder postlock-in(P=1.43 x10-6).UDVA in the LAL group was 20/20 or better in 79%of patients post lock-in with good stability over 12 mo compared with 33%of the control patients with UDVA of 20/20 or better.CONCLUSION:These results demonstrate that the LAL is more effective in achieving target refractions and improving postoperative UDVA in patients with pre-existing corneal astigmatism than a standard monofocal lens. 展开更多
关键词 light adjustable lens monofocal lens ASTIGMATISM CATARACT
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Optical design of adjustable light emitting diode for different lighting requirements 被引量:1
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作者 芦佳宁 余杰 +1 位作者 童玉珍 张国义 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第12期436-439,共4页
Light emitting diode (LED) sources have been widely used for illumination. Optical design, especially freedom compact lens design is necessary to make LED sources applied in lighting industry, such as large-range in... Light emitting diode (LED) sources have been widely used for illumination. Optical design, especially freedom compact lens design is necessary to make LED sources applied in lighting industry, such as large-range interior lighting and small-range condensed lighting. For different lighting requirements, the size of target planes should be variable. In our paper we provide a method to design freedom lens according to the energy conservation law and Snell law through establishing energy mapping between the luminous flux emitted by a Lambertian LED source and a certain area of the target plane. The algorithm of our design can easily change the radius of each circular target plane, which makes the size of the target plane adjustable. Ray-tracing software Tracepro is used to validate the illuminance maps and polar-distribution maps. We design lenses for different sizes of target planes to meet specific lighting requirements. 展开更多
关键词 LED optical design freedom compact lens energy mapping adjustable TRACEPRO
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Rigidloop Adjustable可调袢钢板治疗踝关节骨折并下胫腓联合损伤 被引量:4
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作者 李宏亮 黄涛 +3 位作者 卞峰 方红育 周少怀 范明宇 《生物骨科材料与临床研究》 CAS 2024年第3期49-52,共4页
目的比较Rigidloop Adjustable(RLA)可调袢钢板与螺钉治疗踝关节骨折合并下胫腓联合损伤的临床效果。方法回顾性分析2019年9月至2022年5月武汉市第三医院收治的44例踝关节骨折合并下胫腓联合损伤的患者。踝关节骨折行切开复位内固定后,... 目的比较Rigidloop Adjustable(RLA)可调袢钢板与螺钉治疗踝关节骨折合并下胫腓联合损伤的临床效果。方法回顾性分析2019年9月至2022年5月武汉市第三医院收治的44例踝关节骨折合并下胫腓联合损伤的患者。踝关节骨折行切开复位内固定后,下胫腓联合采用RLA可调袢钢板固定22例,2枚皮质骨螺钉三皮质骨固定22例。应用AOFAS踝与后足功能评分、术侧与健侧踝关节活动度平均差值及术前、术后随访时正位X线片下胫腓间隙(tibiofibular bottom clear space,TBCS)、下胫腓重叠距离(tibiofibular bottom overlap,TBOL)比较两组临床效果。结果患者均获得随访,随访时间12~18个月,平均(16.41±1.66)个月。患者踝关节功能满意,无伤口感染、皮肤激惹等并发症。术后3、6、12个月时,RLA可调袢钢板组双侧踝关节活动度差值均显著小于螺钉组,差异有统计学意义(P<0.05);术后3、6、12个月时,两组的AOFAS评分比较,差异无统计学意义(P>0.05);TBCS、TBOL术前、术后即刻、术后3个月及末次随访时,差异无统计学意义(P>0.05)。结论RLA可调袢钢板和螺钉均可有效固定下胫腓联合,与螺钉固定相比,RLA可调袢钢板组可早期功能锻炼,获得更好的踝关节活动度。 展开更多
关键词 踝关节骨折 下胫腓联合损伤 弹性固定 Rigidloop adjustable(RLA)可调袢钢板 皮质骨螺钉
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Development of adjustable permanent magnet Zeeman slowers for optical lattice clocks 被引量:3
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作者 张晓航 徐信业 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第5期102-107,共6页
We develop a permanent-magnet Zeeman slower with adjustable magnets along the longitudinal and radial directions.Produced by four arrays of cylindrical magnets, the longitudinal magnetic field in the slower is tunable... We develop a permanent-magnet Zeeman slower with adjustable magnets along the longitudinal and radial directions.Produced by four arrays of cylindrical magnets, the longitudinal magnetic field in the slower is tunable if relevant parameters vary, for example, laser detuning or intensity. The proposed Zeeman slower can be reconfigured for Sr atoms. Additionally,we demonstrate that the residual magnetic field produced by the permanent magnets in the magneto-optical trap region can be as small as 0.5 Gs. 展开更多
关键词 permanent magnet slower adjustable longitudinal dipole tunable clock directions captured
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Insight into the reaction mechanism of sulfur chains adjustable polymer cathode for high-loading lithium-organosulfur batteries 被引量:2
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作者 Jinqiu Zhou Xi Zhou +3 位作者 Yawen Sun Xiaowei Shen Tao Qian Chenglin Yan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第5期238-244,共7页
Small molecules with adjustable sulfur atoms in the confined structure were acted as precursor for the synthesis of polymer cathodes for lithium-organosulfur batteries.Among them,poly(diallyl tetrasulfide)(PDATtS)deli... Small molecules with adjustable sulfur atoms in the confined structure were acted as precursor for the synthesis of polymer cathodes for lithium-organosulfur batteries.Among them,poly(diallyl tetrasulfide)(PDATtS)delivered a high capacity of 700 mAh g^(-1),stable capacity retention of 85%after 300 cycles,high areal capacity~4 m Ah cm^(-2) for electrode with up to 10.3 mg cm^(-2) loading.New insight into the reaction mechanism of PDATtS electrode that radicals arisen from the homolytic cleavage of S-S bond in PDATtS reacted with Li+to generate thiolates(RSLi)and insoluble lithium sulfides(Li_(2)S)or lithium disulfide(Li_(2)S_(2))was clearly verified by in-situ UV/Vis spectroscopy,nuclear magnetic resonance(NMR)studies and density-functional theory(DFT)calculations.Therefore,based on the unique reaction mechanism,problems of rapid capacity fading due to the formation of soluble polysulfide intermediates and their serious shuttle effect in conventional lithium-sulfur(Li-S)batteries was totally avoided,realizing the dendrite-free lithium sulfur batteries.This study sets new trends for avenues of further research to advance Li-S battery technologies. 展开更多
关键词 Lithium-sulfur battery Organosulfur polymer adjustable sulfur chains Cathode material
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Numerical Simulation of Axial Inflow Characteristics and Aerodynamic Noise in a Large-Scale Adjustable-Blade Fan 被引量:4
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作者 Lin Wang Chunguo An +4 位作者 Nini Wang Yaming Ping Kun Wang Ming Gao Suoying He 《Fluid Dynamics & Materials Processing》 EI 2020年第3期585-600,共16页
Numerical simulation are conducted to explore the characteristics of the axial inflow and related aerodynamic noise for a large-scale adjustable fan with the installation angle changing from−12°to 12°.In suc... Numerical simulation are conducted to explore the characteristics of the axial inflow and related aerodynamic noise for a large-scale adjustable fan with the installation angle changing from−12°to 12°.In such a range the maximum static(gauge)pressure at the inlet changes from−2280 Pa to 382 Pa,and the minimum static pressure decreases from−3389 Pa to−8000 Pa.As for the axial intermediate flow surface,one low pressure zone is located at the junction of the suction surface and the hub,another is located at the suction surface close to the casing position.At the outlet boundary,the low pressure is negative and decreases from−1716 Pa to−4589 Pa.The sound pressure level of the inlet and outlet noise tends to increase monotonously by 11.6 dB and 7.3 dB,respectively.The acoustic energy of discrete noise is always higher than that of broadband noise regardless of whether the inlet or outlet flow surfaces are considered.The acoustic energy ratio of discrete noise at the inlet tends to increase from 0.78 to 0.93,while at the outlet it first decreases from 0.79 to 0.73 and then increases to 0.84. 展开更多
关键词 adjustable blade axial flow fan variable installation angle condition axial static pressure aerodynamic noise
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Experimental investigation of an adjustable ejector for CO_2 heat pump water heaters 被引量:3
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作者 Guang-ming CHEN Li-xia LIANG Li-ming TANG Xiao-xiao XU Zhi-jiang ZHU Qi CHEN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第11期1678-1682,共5页
An adjustable ejector expansion device for a CO2 heat pump water heater (HPWP) is proposed to improve the system performance. It has been designed to investigate experimentally the effects of the motive nozzle throat ... An adjustable ejector expansion device for a CO2 heat pump water heater (HPWP) is proposed to improve the system performance. It has been designed to investigate experimentally the effects of the motive nozzle throat area of the ejector, entrained flow pressure, back pressure and primary flow pressure on the entrainment ratio. Experiments based on different motive nozzle throat areas were conducted and the results of the prototype ejector using CO2 as working fluid are presented. The results show that an adjustable ejector can achieve high performance and work well in a wide range of working conditions. 展开更多
关键词 adjustable elector System nerformance CO2 heat oumo water heater (HPWH) Entrainment ratio
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