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Research on the longitudinal protection of a through-type cophase traction direct power supply system based on the empirical wavelet transform
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作者 Lu Li Zeduan Zhang +5 位作者 Wang Cai Qikang Zhuang Guihong Bi Jian Deng Shilong Chen Xiaorui Kan 《Global Energy Interconnection》 EI CSCD 2024年第2期206-216,共11页
This paper proposes a longitudinal protection scheme utilizing empirical wavelet transform(EWT)for a through-type cophase traction direct power supply system,where both sides of a traction network line exhibit a disti... This paper proposes a longitudinal protection scheme utilizing empirical wavelet transform(EWT)for a through-type cophase traction direct power supply system,where both sides of a traction network line exhibit a distinctive boundary structure.This approach capitalizes on the boundary’s capacity to attenuate the high-frequency component of fault signals,resulting in a variation in the high-frequency transient energy ratio when faults occur inside or outside the line.During internal line faults,the high-frequency transient energy at the checkpoints located at both ends surpasses that of its neighboring lines.Conversely,for faults external to the line,the energy is lower compared to adjacent lines.EWT is employed to decompose the collected fault current signals,allowing access to the high-frequency transient energy.The longitudinal protection for the traction network line is established based on disparities between both ends of the traction network line and the high-frequency transient energy on either side of the boundary.Moreover,simulation verification through experimental results demonstrates the effectiveness of the proposed protection scheme across various initial fault angles,distances to faults,and fault transition resistances. 展开更多
关键词 Through-type Cophase traction direct power supply system Traction network Empirical wavelet transform(EWT) longitudinal protection
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Longitudinal Evaluation of Hemiplegic Ankle Rehabilitation Efficacy by Wearable Inertial Sensor Systems with an Assortment of Machine Learning Algorithms
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作者 Robert LeMoyne Timothy Mastroianni 《Journal of Biomedical Science and Engineering》 2023年第9期121-131,共11页
With the amalgamation of wearable systems equipped with inertial sensors, such as a gyroscope, and machine learning a therapy regimen can be objectively quantified, and then the initial phase and final phase of a one ... With the amalgamation of wearable systems equipped with inertial sensors, such as a gyroscope, and machine learning a therapy regimen can be objectively quantified, and then the initial phase and final phase of a one year therapy regimen can be distinguished through machine learning. In the context of rehabilitation of a hemiplegic ankle, a longitudinal therapy regimen incorporating stretching and then a series of repetitions for raising and lowering the foot of the hemiplegic ankle can be applied over the course of a year. Using a smartphone equipped with an application to function as a wearable and wireless gyroscope platform mounted to the dorsum of the foot by an armband, the initial phase and final phase of a one year longitudinally applied therapy regimen can be objectively quantified and recorded for subsequent machine learning. Considerable classification accuracy is attained to distinguish between the initial phase and final phase by a support vector machine for a one year longitudinally applied hemiplegic ankle therapy regimen based on the gyroscope signal data obtained by a smartphone functioning as a wearable and wireless inertial sensor system. . 展开更多
关键词 Smartphone GYROSCOPE Machine Learning HEMIPARESIS Rehabilitation ANKLE longitudinal Evaluation
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Semi-analytical investigation of heat transfer in a porous convective radiative moving longitudinal fin exposed to magnetic field in the presence of a shape-dependent trihybrid nanofluid
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作者 C.G.PAVITHRA B.J.GIREESHA M.L.KEERTHI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第1期197-216,共20页
The thermal examination of a non-integer-ordered mobile fin with a magnetism in the presence of a trihybrid nanofluid(Fe_3O_4-Au-Zn-blood) is carried out. Three types of nanoparticles, each having a different shape, a... The thermal examination of a non-integer-ordered mobile fin with a magnetism in the presence of a trihybrid nanofluid(Fe_3O_4-Au-Zn-blood) is carried out. Three types of nanoparticles, each having a different shape, are considered. These shapes include spherical(Fe_3O_4), cylindrical(Au), and platelet(Zn) configurations. The combination approach is utilized to evaluate the physical and thermal characteristics of the trihybrid and hybrid nanofluids, excluding the thermal conductivity and dynamic viscosity. These two properties are inferred by means of the interpolation method based on the volume fraction of nanoparticles. The governing equation is transformed into a dimensionless form, and the Adomian decomposition Sumudu transform method(ADSTM) is adopted to solve the conundrum of a moving fin immersed in a trihybrid nanofluid. The obtained results agree well with those numerical simulation results, indicating that this research is reliable. The influence of diverse factors on the thermal overview for varying noninteger values of γ is analyzed and presented in graphical representations. Furthermore, the fluctuations in the heat transfer concerning the pertinent parameters are studied. The results show that the heat flux in the presence of the combination of spherical, cylindrical, and platelet nanoparticles is higher than that in the presence of the combination of only spherical and cylindrical nanoparticles. The temperature at the fin tip increases by 0.705 759% when the value of the Peclet number increases by 400%, while decreases by 11.825 13% when the value of the Hartman number increases by 400%. 展开更多
关键词 convection radiation moving longitudinal fin Adomian decomposition Sumudu transform method(ADSTM) trihybrid nanofluid magnetic field
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Longitudinal vibration characteristics of a tapered pipe pile considering the vertical support of surrounding soil and construction disturbance
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作者 Li Zhenya Pan Yunchao +2 位作者 He Xianbin Lv Chong Mohammad Towhid 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期51-63,共13页
This research is concentrated on the longitudinal vibration of a tapered pipe pile considering the vertical support of the surrounding soil and construction disturbance.First,the pile-soil system is partitioned into f... This research is concentrated on the longitudinal vibration of a tapered pipe pile considering the vertical support of the surrounding soil and construction disturbance.First,the pile-soil system is partitioned into finite segments in the vertical direction and the Voigt model is applied to simulate the vertical support of the surrounding soil acting on the pile segment.The surrounding soil is divided into finite ring-shaped zones in the radial direction to consider the construction disturbance.Then,the shear complex stiffness at the pile-soil interface is derived by solving the dynamic equilibrium equation for the soil from the outermost to innermost zone.The displacement impedance at the top of an arbitrary pile segment is obtained by solving the dynamic equilibrium equation for the pile and is combined with the vertical support of the surrounding soil to derive the displacement impedance at the bottom of the upper adjacent segment.Further,the displacement impedance at the pile head is obtained based on the impedance function transfer technique.Finally,the reliability of the proposed solution is verified,followed by a sensitivity analysis concerning the coupling effect of the pile parameters,construction disturbance and the vertical support of the surrounding soil on the displacement impedance of the pile. 展开更多
关键词 tapered pipe pile longitudinal vibration vertical support of the surrounding soil construction disturbance displacement impedance
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Transverse mode-coupling instability with longitudinal impedance
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作者 Hai-Sheng Xu Chun-Tao Lin +2 位作者 Na Wang Jing-Ye Xu Yuan Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第6期40-53,共14页
Transverse mode-coupling instability(TMCI)is a dangerous transverse single-bunch instability that can lead to severe par-ticle loss.The mechanism of TMCI can be explained by the coupling of transverse coherent oscilla... Transverse mode-coupling instability(TMCI)is a dangerous transverse single-bunch instability that can lead to severe par-ticle loss.The mechanism of TMCI can be explained by the coupling of transverse coherent oscillation modes owing to the transverse short-range wakefield(i.e.,the transverse broadband impedance).Recent studies on future circular colliders,e.g.,FCC-ee,showed that the threshold of TMCI decreased significantly when both longitudinal and transverse impedances were included.We performed computations for the circular electron-positron collider(CEPC)and observed a similar phenom-enon.Systematic studies on the influence of longitudinal impedance on the TMCI threshold were conducted.We concluded that the imaginary part of the longitudinal impedance,which caused a reduction in the incoherent synchrotron tune,was the primary reason for the reduction in the TMCI threshold.Additionally,the real part of the longitudinal impedance assists in increasing the TMCI threshold. 展开更多
关键词 Transverse mode-coupling instability longitudinal impedance
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Factor Structure and Longitudinal Invariance of the CES-D across Diverse Residential Backgrounds in Chinese Adolescents
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作者 Yanjing Cao Chenchen Xu +2 位作者 Qi Li Shan Lu Jing Xiao 《International Journal of Mental Health Promotion》 2024年第4期261-269,共9页
Background:Valid and reliable measures of depressive symptoms are crucial for understanding risk factors,outcomes,and interventions across rural and urban settings.Despite this need,the longitudinal invariance of thes... Background:Valid and reliable measures of depressive symptoms are crucial for understanding risk factors,outcomes,and interventions across rural and urban settings.Despite this need,the longitudinal invariance of these measures over time remains understudied.This research explores the structural components of the Center for Epidemiological Studies Depression Scale(CES-D)and examines its consistency across various living environments and temporal stability in a cohort of Chinese teenagers.Method:In the initial phase,1,042 adolescents furnished demographic details and undertook the CES-D assessment.After a three-month interval,967 of these participants repeated the CES-D evaluation.The study employed Confirmatory factor analysis(CFA)to scrutinize the scale’s structural integrity.We investigated factorial invariance by conducting a twopronged CFA:one comparing urban vs.rural backgrounds,and another contrasting the results from the initial assessment with those from the follow-up.Results:The CES-D demonstrated adequate reliability in both rural and urban high school student samples.The preliminary four-factor model applied to the CES-D demonstrated a good fit with the collected data.Invariance tests,including multigroup analyses comparing rural and urban samples and longitudinal assessments,confirmed the scale’s invariance.Conclusions:The results suggest that the CES-D serves as a reliable instrument for evaluating depressive symptoms among Chinese adolescents.Its applicability is consistent across different living environments and remains stable over time. 展开更多
关键词 DEPRESSION factor structure measurement invariance Chinese adolescent longitudinal invariance
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Distribution Line Longitudinal ProtectionMethod Based on Virtual Measurement Current Restraint
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作者 WeiWang Yang Yu +3 位作者 Simin Luo Wenlin Liu Wei Tang Yuanbo Ye 《Energy Engineering》 EI 2024年第2期315-337,共23页
As an effective approach to achieve the“dual-carbon”goal,the grid-connected capacity of renewable energy increases constantly.Photovoltaics are the most widely used renewable energy sources and have been applied on ... As an effective approach to achieve the“dual-carbon”goal,the grid-connected capacity of renewable energy increases constantly.Photovoltaics are the most widely used renewable energy sources and have been applied on various occasions.However,the inherent randomness,intermittency,and weak support of grid-connected equipment not only cause changes in the original flow characteristics of the grid but also result in complex fault characteristics.Traditional overcurrent and differential protection methods cannot respond accurately due to the effects of unknown renewable energy sources.Therefore,a longitudinal protection method based on virtual measurement of current restraint is proposed in this paper.The positive sequence current data and the network parameters are used to calculate the virtual measurement current which compensates for the output current of photovoltaic(PV).The waveform difference between the virtual measured current and the terminal current for internal and external faults is used to construct the protection method.An improved edit distance algorithm is proposed to measure the similarity between virtual measurement current and terminal measurement current.Finally,the feasibility of the protection method is verified through PSCAD simulation. 展开更多
关键词 Photovoltaic interconnection distribution network longitudinal protection method edit distance algorithm
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Screening of Myocardial Cardiotoxicity Induced by Anticancer Chemotherapy and the Importance of Global Longitudinal Strain
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作者 Marguerite Téning Diouf Fatou Aw +20 位作者 Hussein Khadra Sophie Ba Doudou Diouf Michel Ngonar Sarr Joseph Salvador Mingou Malick Ndiaye Simon Antoine Sarr Momar Dioum Aliou Alassane Ngaide Serigne Mor Beye Simon Manga Alain Affangla Youssou Diouf Khadimu Rassoul Diop Malick Bodian Mohamed Leye Mouhamadou Bamba Ndiaye Alassane Mbaye Adama Kane Maboury Diao Abdoul Kane 《World Journal of Cardiovascular Diseases》 CAS 2024年第6期381-391,共11页
Introduction: The improvement of survival in patients with cancer and the expansion of therapeutic options have led to the emergence of a new profile of cardiotoxicity, specifically associated with antimitotic agents.... Introduction: The improvement of survival in patients with cancer and the expansion of therapeutic options have led to the emergence of a new profile of cardiotoxicity, specifically associated with antimitotic agents. Our study aimed to assess the incidence of chemotherapy-induced myocardial toxicity in patients with cancer. Patients and Methods: We conducted a looking-forward longitudinal cohort study including all patients admitted to the Cardiology departments of Aristide le Dantec Hospital and Dalal Jamm National Hospital Centre for apre-chemotherapy check-up. The included patients did not undergo any pre-existing cardiopathy. Results: Over a period of two years ranging from January 2019 to December 2021, a total of 37 patients were included in the study. Notably, there was a female predominance (92%) with an average age of 49.7 years ± 13.69. Breast cancer accounted for 70% of the neoplasms. Laboratory findings revealed moderate anemia in 19 patients (51%). At inclusion, the left ventricle (LV) was of normal size (LV diastole at 44.46 ± 4.97 mm). The systolic function of the left ventricle was normal in all patients, with an average ejection fraction (EF) of 63.1% ± 5.80 and a mean global longitudinal strain (GLS) of −20.4% ± 2.58. The most commonly used agents were anthracyclines. During follow-up, 3 patients (8.1%) developed clinical symptoms of left heart failure, and LV dysfunction on echocardiography was observed in 5 (13.5%) patients, with a significant decrease in EF Conclusion: The incidence of cardiac toxicity is not negligible, hence the importance of early screening. Strain imaging is an essential tool that should be performed as part of the assessment before chemotherapy and re-evaluated during treatment. 展开更多
关键词 Cancer CHEMOTHERAPY Global longitudinal Strain CARDIOTOXICITY
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Flexible pavement longitudinal joint quality evaluation using non-destructive testing
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作者 Hamad Bin Muslim Syed Waqar Haider Lev Khazanovich 《Journal of Road Engineering》 2024年第2期189-202,共14页
Longitudinal joint construction quality is critical to the life of flexible pavements.Maintaining deteriorated longitudinal joints has become a challenge for many highway agencies.Improving the joint's quality thr... Longitudinal joint construction quality is critical to the life of flexible pavements.Maintaining deteriorated longitudinal joints has become a challenge for many highway agencies.Improving the joint's quality through better compaction during construction can help achieve flexible pavements with longer service lives and less maintenance.Current quality control(QC)and quality assurance(QA)plans provide limited coverage.Consequently,the risk of missing areas with poor joint compaction is significant.A density profiling system(DPS)is a non-destructive alternative to conventional destructive evaluation methods.It can provide quick and continuous real-time coverage of the compaction during construction in dielectrics.The paper presents several case studies comparing various types of longitudinal joints and demonstrating the use of DPS to evaluate the joint's compaction quality.The paper shows that dielectric measurements can provide valuable insight into the ability of various construction techniques to achieve adequate levels of compaction at the longitudinal joint.The paper proposes a dielectric-based longitudinal joint quality index(LJQI)to evaluate the relative compaction of the joint during construction.It also shows that adopting DPS for assessing the compaction of longitudinal joints can minimize the risk of agencies accepting poorly constructed joints,identify locations of poor quality during construction,and achieve better-performing flexible pavements. 展开更多
关键词 Sustainable pavements Dielectric/density profiling system Quality assurance Non-destructive testing Asphalt longitudinal joint
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Research on the Resistance of Cutting Mechanism of Mining Longitudinal Roadheader
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作者 Mengjiao NIU Yong ZHAO Yongliang YUAN 《Mechanical Engineering Science》 2024年第1期8-12,共5页
In order to accurately obtain the dynamic characteristics of the cutting mechanism of the mining longitudinal roadheader,combined with the working principle of the mining longitudinal roadheader,the theoretical analys... In order to accurately obtain the dynamic characteristics of the cutting mechanism of the mining longitudinal roadheader,combined with the working principle of the mining longitudinal roadheader,the theoretical analysis and derivation are carried out in detail.By using ADAMS to simulate,the resistance curve and torque curve of the cutting mechanism in different directions are obtained.The results show that ADAMS can effectively predict the excavation resistance and torque of the cutting mechanism of mining longitudinal roadheader,which has certain reference value for future optimization design. 展开更多
关键词 longitudinal roadheader cutting mechanism dynamic characteristics DYNAMICS
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Simulation study of longitudinal injection scheme for HALS with a higher harmonic cavity system 被引量:4
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作者 Zhen-Biao Sun Lei Shang +3 位作者 Feng-Lei Shang Yun-Gai Tang Wei Liu Wen-Bin Song 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第7期77-82,共6页
Longitudinal injection is a promising on-axis injection scheme for diffraction-limited storage rings. In the latest version of the Hefei advanced light source (HALS), both the dynamic aperture and momentum aperture ha... Longitudinal injection is a promising on-axis injection scheme for diffraction-limited storage rings. In the latest version of the Hefei advanced light source (HALS), both the dynamic aperture and momentum aperture have been optimized. A longitudinal injection scheme was investigated on the HALS using a doublefrequency radio frequency system. To evaluate the injection performance, various errors were considered. A series of tracking simulations were conducted, and the injection efficiency was obtained under different error levels. 展开更多
关键词 longitudinal INJECTION Hefei advanced LIGHT SOURCE Double-frequency RF system INJECTION efficiency
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An Integrated Dynamic Model of Ocean Mining System and Fast Simulation of Its Longitudinal Reciprocating Motion 被引量:3
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作者 戴瑜 刘少军 《China Ocean Engineering》 SCIE EI CSCD 2013年第2期231-244,共14页
An integrated dynamic model of China's deep ocean mining system is developed and the fast simulation analysis of its longitudinal reciprocating motion operation processes is achieved. The seafloor tracked miner is bu... An integrated dynamic model of China's deep ocean mining system is developed and the fast simulation analysis of its longitudinal reciprocating motion operation processes is achieved. The seafloor tracked miner is built as a three-dimensional single-body model with six-degree-of-freedom. The track-terrain interaction is modeled by partitioning the track-terrain interface into a certain number of mesh elements with three mutually perpendicular forces, including the normal force, the longitudinal shear force and the lateral shear force, acting on the center point of each mesh element. The hydrodynamic force of the miner is considered and applied. By considering the operational safety and collection efficiency, two new mining paths for the miner on the seafloor are proposed, which can be simulated with the established single-body dynamic model of the miner. The pipeline subsystem is built as a three-dimensional multi-body discrete element model, which is divided into rigid elements linked by flexible connectors. The flexible connector without mass is represented by six spring-damper elements. The external hydrodynamic forces of the ocean current from the longitudinal and lateral directions are both considered and modeled based on the Morison formula and applied to the mass center of each corresponding discrete rigid element. The mining ship is simplified and represented by a general kinematic point, whose heave motion induced by the ocean waves and the longitudinal and lateral towing motions are considered and applied. By integrating the single-body dynamic model of the miner and the multi-body discrete element dynamic model of the pipeline, and defining the kinematic equations of the mining ship, the integrated dynamic model of the total deep ocean mining system is formed. The longitudinal reciprocating motion operation modes of the total mining system, which combine the active straight-line and turning motions of the miner and the ship, and the passive towed motions of the pipeline, are proposed and simulated with the developed 3D dynamic model. Some critical simulation results are obtained and analyzed, such as the motion trajectories of key subsystems, the velocities of the buoyancy modules and the interaction forces between subsystems, which in a way can provide important theoretical basis and useful technical reference for the practical deep ocean mining system analysis, operation and control. 展开更多
关键词 deep ocean mining system single-body model track-terrain interaction model discrete element model longitudinal reciprocating motion operation mode dynamic simulation analysis
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Longitudinal Performance Assessment of Traffic Signal System Impacted by Long-Term Interstate Construction Diversion Using Connected Vehicle Data 被引量:6
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作者 Enrique D. Saldivar-Carranza Margaret Hunter +2 位作者 Howell Li Jijo Mathew Darcy M. Bullock 《Journal of Transportation Technologies》 2021年第4期644-659,共16页
Local arterials can be significantly impacted by diversions from adjacent work zones. These diversions often occur on unofficial detour routes due to guidance received on personal navigation devices. Often, these rout... Local arterials can be significantly impacted by diversions from adjacent work zones. These diversions often occur on unofficial detour routes due to guidance received on personal navigation devices. Often, these routes do not have sufficien<span style="font-family:Verdana;">t sensing or communication equipment to obtain infrastructure-based tra</span><span style="font-family:Verdana;">ffic signal performance measures, so other data sources are required to identify locations being significantly affected by diversions. This paper examines the network impact caused by the start of an 18-month closure of the I-65/70 interchange (North Split), which usually serves approximately 214,000 vehicles per day in Indianapolis, IN. In anticipation of some proportion of the public diverting from official detour routes to local streets, a connected vehicle monitoring program was established to provide daily performances measures for over 100 intersections in the area without the need for vehicle sensing equipment. This study reports on 13 of the most impacted signals on an alternative arterial to identify locations and time of day where operations are most degraded, so that decision makers have quantitative information to make informed adjustments to the system. Individual vehicle movements at the studied locations are analyzed to estimate changes in volume, split failures, downstream blockage, arrivals on green, and travel times. Over 130,000 trajectories were analyzed in an 11-week period. Weekly afternoon peak period volumes increased by approximately 455%, split failures increased 3%, downstream blockage increased 10%, arrivals on green decreased 16%, and travel time increase 74%. The analysis performed in this paper will serve as a framework for any agency that wants to assess traffic signal performance at hundreds of locations with little or no existing sensing or communication infrastructure to prioritize tactical retiming and/or longer-term infrastructure investments.</span> 展开更多
关键词 Traffic Signal Performance Measures Connected Vehicle longitudinal Study Big Data
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Evaluation of Venous Ammonia Level, Splenic Longitudinal Diameter, Portal Vein and Splenic Vein Diameters as Non-Invasive Indicators for the Presence of Portosystemic Collaterals in Egyptian Cirrhotic Patients 被引量:2
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作者 Mohamed F. Montasser Heba M. Abdella Amir Helmy Samy 《Open Journal of Gastroenterology》 2014年第6期265-274,共10页
Introduction and Aim of the Work: The identification of cirrhotic patients with esophageal varices or other portosystemic collateral by non-invasive means is appealing in that it could decrease the necessity of endosc... Introduction and Aim of the Work: The identification of cirrhotic patients with esophageal varices or other portosystemic collateral by non-invasive means is appealing in that it could decrease the necessity of endoscopic screening. This study was to evaluate the diagnostic utility of venous ammonia level with other ultrasonographic parameters as non-invasive markers for the presence of portosystemic shunts. Patients and methods: The study included 3 groups of Child Pugh class A and early B patients. Group (A): 25 patients with evidence of both esophageal varices and portosystemic collaterals;group (B) 25 patients with neither evidence of varices nor portosystemic collaterals and group (C): 25 patients with evidence of varices but no collaterals. Measurement of venous ammonia level was done for all patients. Results: serum ammonia level was significantly higher in group A (222.8 ± 54 μg/dL) than that in group B (85 ± 21.1 μg/dL) and group C (148.2 ± 19.6 μg/dL). The cut-off value of serum ammonia level 113 μg/dL was a good predictor for the presence of esophageal varices, while the cut-off value of serum ammonia level at 133 μg/dL was a good predictor for the presence of both esophageal varices and abdominal collaterals. Combination of portal vein diameter > 13mm + splenic vein diameter > 8.9mm + ammonia level > 133 μg/dL gives 100% of sensitivity and 96% of specificity for the prediction of the presence of portosystemic shunts. Conclusion: Determination of serum ammonia level, splenic, portal vein and splenic vein diameters are considered as good predictors for the presence of portosystemic shunts in patients with liver cirrhosis. 展开更多
关键词 Serum Ammonia Potosystemic COLLATERALS PORTAL Hypertension Esophageal VARICES SPLENIC VEIN DIAMETER PORTAL VEIN DIAMETER SPLENIC longitudinal DIAMETER
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Fuzzy Sliding Mode Control Based on Longitudinal Force Estimation for Electro-mechanical Braking Systems using BLDC Motor 被引量:3
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作者 Xiaoyan Peng Mingfei Jia +2 位作者 Lei He Xiang Yu Yibin Lv 《CES Transactions on Electrical Machines and Systems》 2018年第1期142-151,共10页
This paper focuses on the controller design using fuzzy sliding mode control(FSMC)with application to electro-mechanical brake(EMB)systems using BLDC Motor.The EMB controller transmits the control signal to the motor ... This paper focuses on the controller design using fuzzy sliding mode control(FSMC)with application to electro-mechanical brake(EMB)systems using BLDC Motor.The EMB controller transmits the control signal to the motor driver to rotate the motor.The torque distribution of motors is studied in this paper actually.Firstly,the model of the EMB system is established.Then the state observer is developed to estimate the vehicle states including the vehicle velocity and longitudinal force.Due to the fact that the EMB system is nonlinear and uncertain,a FSMC strategy based on wheel slip ratio is proposed,where both the normal and emergency braking conditions are taken into account.The equivalent control law of sliding mode controller is designed on the basis of the variation of the front axle and rear axle load during the brake process,while the switching control law is adjusted by the fuzzy corrector.The simulation results illustrate that the FSMC strategy has the superior performance,better adaptability to various types of roads,and shorter braking distance,as compared to PID control and traditional sliding mode control technologies.Finally,the hardware-in-loop(HIL)experimental results have exemplified the validation of the developed methodology. 展开更多
关键词 BLDC Motor electro-mechanical brake fuzzy sliding mode control longitudinal force estimation hardware-in-loop experiments wheel slip ratio
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Longitudinal Vibration Analysis of Elastically Coupled Nanorods System with General Boundary Supports
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作者 Deshui Xu Jingtao Du Yuhao Zhao 《Sound & Vibration》 2019年第2期16-28,共13页
In this paper,an accurate series solution for the longitudinal vibration analysis of elastically coupled nanorods system is established,in which artificial springs are introduced to simulate such general coupling and ... In this paper,an accurate series solution for the longitudinal vibration analysis of elastically coupled nanorods system is established,in which artificial springs are introduced to simulate such general coupling and boundary conditions.Energy formulation is derived for the description of axial dynamics of multiple coupled nanorods based on Eringen nonlocal elasticity.For each nanorod component,its longitudinal vibration displacement function is invariantly assumed as the superposition of Fourier series and boundary smoothed supplementary polynomials,with the aim to make all the spatial differential sufficiently continuous across each rod.All the unknown coefficients are determined in conjunction with Rayleigh-Ritz procedure to solve a standard eigenvalue matrix.Numerical results are presented for the particular cases of twonanorod and three-nanorod systems to demonstrate the correctness and effectiveness of the proposed model.Excellent agreements can be repeatedly observed in comparison with those from other approaches available in literature.Based on the model established,influence of elastic boundary and coupling conditions on the longitudinal modal characteristics of multiple nanorods system is investigated and addressed.This work can provide an efficient energy-based modeling framework for longitudinal vibration analysis of elastically connected nanorod system with complicated boundary conditions. 展开更多
关键词 longitudinal VIBRATION NANORODS system ELASTIC BOUNDARY and COUPLING energy-based method
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Reporting of longitudinal pancreatojejunostomy with partial pancreatic head resection(the Frey procedure) for chronic pancreatitis: A systematic review
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作者 Minas Baltatzis Santhalingam Jegatheeswaran Ajith K Siriwardena 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2021年第2期110-116,共7页
Background:Longitudinal pancreatojejunostomy with partial pancreatic head resection(the Frey procedure)is accepted for surgical treatment of painful chronic pancreatitis.However,conduct and reporting are not standardi... Background:Longitudinal pancreatojejunostomy with partial pancreatic head resection(the Frey procedure)is accepted for surgical treatment of painful chronic pancreatitis.However,conduct and reporting are not standardized and thus,making comparisons difficult.This study assesses the reporting standards of this procedure.Data sources:A systematic literature review was performed between January 1987 and January 2020.The keyword and Medical Subject Heading"chronic pancreatitis"was used together with the individual operation term"Frey pancreatojejunostomy".Reports were included if they provided original information on conduct and outcome.Thirty-three papers providing information on 1205 patients constituted the study population.Risk of bias in included reports was assessed.Results:Etiology of chronic pancreatitis(alcohol)was reported in 26 of 28(93%)studies,duration of symptoms prior to surgery in 19(58%)studies and pre-operative opiate use in 12(36%)studies.In terms of morphology,pancreatic duct diameter was reported in 17(52%)studies and diameter of the pancreatic head in 13(39%)studies.In terms of technique,three(9%)studies reported weight of excised parenchyma.There were 9(0.7%)procedure-related deaths.Post-operative follow-up ranged from 6 to 82.5 months.No studies reported post-operative portal hypertension.Conclusions:There is substantial heterogeneity between studies in reporting of clinical baseline,morphology of the diseased pancreas,operative detail and outcome after longitudinal pancreatojejunostomy with partial pancreatic head resection.This critically compromises the comparison between centers and between surgeons.Structured reporting is necessary for clinicians to assess choice of procedure and for patients to make informed choices when seeking treatment for painful chronic pancreatitis. 展开更多
关键词 Chronic pancreatitis Frey procedure REPORTING longitudinal pancreatojejunostomy
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Mechanism of Generation and Collapse of a Longitudinal Vortex System Induced around the Leading Edge of a Delta Wing
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作者 Shigeru Ogawa Jumpei Takeda 《Open Journal of Fluid Dynamics》 2015年第3期265-274,共10页
The purpose of the paper is to clarify the mechanism of generation and collapse of a longitudinal vortex system induced around the leading edge of a delta wing. CFD captured well characteristics of flow structure of t... The purpose of the paper is to clarify the mechanism of generation and collapse of a longitudinal vortex system induced around the leading edge of a delta wing. CFD captured well characteristics of flow structure of the vortex system. It is found that the vortex system has a cone-shaped configuration, and both rotational velocity and vorticity have their largest values at the tip of the vortex and reduce downstream along the vortical axis. This resulted in inducing the largest negative pressure at the tip of the delta wing surface. The collapse of the vortex system was also studied. The system can still remain until the tip angle of 110 degrees. However, between 110 degrees and 120 degrees, the system becomes unstable. Over 120 degrees, the characteristics of the vortex are considered to have converted from the longitudinal vortex to the transverse one. 展开更多
关键词 DELTA WING longitudinal VORTEX VORTEX BREAKDOWN CFD
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Analytical solution for longitudinal deformation of shield tunnel induced by overcrossing tunnelling considering circumferential joints
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作者 Zhiwei Zhang Rongzhu Liang +4 位作者 Zhongchao Li Cheng Kang MHEl Naggar Mingzhao Xiao Wenbing Wu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第9期2355-2374,共20页
This paper presents a new analytical solution for assessing the longitudinal deformation of shield tunnel associated with overcrossing tunnelling in consideration of circumferential joints.A simplified longitudinal be... This paper presents a new analytical solution for assessing the longitudinal deformation of shield tunnel associated with overcrossing tunnelling in consideration of circumferential joints.A simplified longitudinal beam-spring model(SLBSM)is established to model the longitudinal behaviours of shield tunnel,which can consider the opening and dislocation between segmental rings simultaneously.Then,the existing tunnel is treated as the SLBSM resting on the elastic foundation.The state equations including tunnel displacements and internal forces are constructed to solve the discontinuous deformation of circumferential joint-segmental ring.The feasibility of the proposed solution is verified through three well-documented cases.The predictions from the proposed method are also compared with other analytical methods.It is found that the proposed method can well capture the deformation of tunnel segmental rings and joints,where the rigid displacement mainly occurs in the segmental rings while the rotation and dislocation occur in the circumferential joints.Some dominant parameters are also analysed to explore the effects on existing tunnel deformation,including the rotation stiffness and shearing stiffness of joints,the skew angle and the clearance between new and old tunnels. 展开更多
关键词 Overcrossing tunnelling Shield tunnel Circumferential joints longitudinal beam-spring model(LBSM) Opening DISLOCATION
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The default mode network is affected in the early stage of simian immunodeficiency virus infection:a longitudinal study
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作者 Zhen-Chao Tang Jiao-Jiao Liu +6 位作者 Xue-Tong Ding Dan Liu Hong-Wei Qiao Xiao-Jie Huang Hui Zhang Jie Tian Hong-Jun Li 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第7期1542-1547,共6页
Acquired immune deficiency syndrome infection can lead to cognitive dysfunction represented by changes in the default mode network.Most recent studies have been cross-sectional and thus have not revealed dynamic chang... Acquired immune deficiency syndrome infection can lead to cognitive dysfunction represented by changes in the default mode network.Most recent studies have been cross-sectional and thus have not revealed dynamic changes in the default mode network following acquired immune deficiency syndrome infection and antiretroviral therapy.Specifically,when brain imaging data at only one time point are analyzed,determining the duration at which the default mode network is the most effective following antiretroviral therapy after the occurrence of acquired immune deficiency syndrome.However,because infection times and other factors are often uncertain,longitudinal studies cannot be conducted directly in the clinic.Therefore,in this study,we performed a longitudinal study on the dynamic changes in the default mode network over time in a rhesus monkey model of simian immunodeficiency virus infection.We found marked changes in default mode network connectivity in 11 pairs of regions of interest at baseline and 10 days and 4 weeks after virus inoculation.Significant interactions between treatment and time were observed in the default mode network connectivity of regions of interest pairs area 31/V6.R and area 8/frontal eye field(FEF).L,area 8/FEF.L and caudal temporal parietal occipital area(TPOC).R,and area 31/V6.R and TPOC.L.ART administered 4 weeks after infection not only interrupted the progress of simian immunodeficiency virus infection but also preserved brain function to a large extent.These findings suggest that the default mode network is affected in the early stage of simian immunodeficiency virus infection and that it may serve as a potential biomarker for early changes in brain function and an objective indicator for making early clinical intervention decisions. 展开更多
关键词 acquired immune deficiency syndrome analysis of variance antiretroviral therapy default mode network functional magnetic resonance imaging human immunodeficiency virus longitudinal study rhesus monkeys simian immunodeficiency virus SIV-mac239
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