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A proposed directional function and wind-wave directional spectrum 被引量:4
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作者 Wen Shengchang Wu Kejian +1 位作者 Guan Changlong Sun Shicai and Zhang Dacuo (Institute of Physical Oceanography, Ocean University of Oingdao, Oingdao 266003, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1995年第2期155-166,共12页
A directional function for frequencies equal to and larger than the peak frequency of a wind-wave frequency spectrum is constructed by fitting the angular spreading based on the analytically derived directional spectr... A directional function for frequencies equal to and larger than the peak frequency of a wind-wave frequency spectrum is constructed by fitting the angular spreading based on the analytically derived directional spectrum of Wen et al. (1993, Journal of Oceanography, 49(2), 131~147, 149~172). For frequencies smaller than the peak frequency, the directional function is obtained by comparing and analyzing existing formulas. The nondimensional wind-wave frequency spectrum of Wen et al. (1994, Progress in Natural Seience, 4(4). 407~427;4 (5), 586~596) has been used together with the directional function just mentioned to obtain the directional spectrum for easier application. 展开更多
关键词 Wind-wave directional function directional spectrum
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Three-dimensional free vibration analysis of multi-directional functionally graded piezoelectric annular plates on elastic foundations via state space based differential quadrature method 被引量:3
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作者 M.H.YAS N.MOLOUDI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第4期439-464,共26页
The three-dimensional free vibration analysis of a multi-directional func- tionally graded piezoelectric (FGP) annular plate resting on two parameter (Pasternak) elastic foundations is investigated under different... The three-dimensional free vibration analysis of a multi-directional func- tionally graded piezoelectric (FGP) annular plate resting on two parameter (Pasternak) elastic foundations is investigated under different boundary conditions. The material properties are assumed to vary continuously along the radial and thickness directions and have exponent-law distribution. A semi-analytical approach named the state space based differential quadrature method (SSDQM) is used to provide an analytical solution along the thickness using the state space method (SSM) and an approximate solution along the radial direction using the one-dimensional differential quadrature method (DQM). The influence of the Winkler and shear stiffness of the foundation~ the material property graded variations, and the circumferential wave number on the nomdimensional natural frequency of multi-directional FGP annular plates is studied. 展开更多
关键词 multi-directional functionally graded PIEZOELECTRIC annular plate freevibration
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AXISYMMETRIC BENDING OF TWO-DIRECTIONAL FUNCTIONALLY GRADED CIRCULAR AND ANNULAR PLATES 被引量:6
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作者 Guojun Nie Zheng Zhong 《Acta Mechanica Solida Sinica》 SCIE EI 2007年第4期289-295,共7页
Assuming the material properties varying with an exponential law both in the thick- ness and radial directions, axisymmetric bending of two-directional functionally graded circular and annular plates is studied using ... Assuming the material properties varying with an exponential law both in the thick- ness and radial directions, axisymmetric bending of two-directional functionally graded circular and annular plates is studied using the semi-analytical numerical method in this paper. The deflections and stresses of the plates are presented. Numerical results show the well accuracy and convergence of the method. Compared with the finite element method, the semi-analytical nu- merical method is with great advantage in the computational efficiency. Moreover, study on ax- isymmetric bending of two-directional functionally graded annular plate shows that such plates have better performance than those made of isotropic homogeneous materials or one-directional functionally graded materials. Two-directional functionally graded material is a potential alternative to the one-directional functionally graded material. And the integrated design of materials and structures can really be achieved in two-directional functionally graded materials. 展开更多
关键词 two-directional functionally graded materials circular and annular plates axisym-metric bending semi-analytical numerical method integrated design
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THE BOREL DIRECTIONS OF ALGEBROIDAL FUNCTION AND ITS COEFFICIENT FUNCTIONS 被引量:2
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作者 张少华 张晓梅 孙道椿 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期241-251,共11页
In this article, the relationship between the Borel direction of algebroidal function and its coefficient functions is studied for the first time. To begin with, several theorems of algebroidal functions in unit disk ... In this article, the relationship between the Borel direction of algebroidal function and its coefficient functions is studied for the first time. To begin with, several theorems of algebroidal functions in unit disk are proved. By these theorems, some interesting conclusions are obtained. 展开更多
关键词 Algebroidal function coefficient function Borel direction.
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ON NEVANLINNA DIRECTIONS OF ALGEBROID FUNCTIONS 被引量:5
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作者 卢谦 顾永兴 《Acta Mathematica Scientia》 SCIE CSCD 2005年第2期367-375,共9页
In this paper, a notation delta(x)(w) is derived from the counting function N-x(r, w) of branch points of algebriod functions. With this notation, the authors give the definition of the Nevanlinna direction for algebr... In this paper, a notation delta(x)(w) is derived from the counting function N-x(r, w) of branch points of algebriod functions. With this notation, the authors give the definition of the Nevanlinna direction for algebriod functions and discuss its existence in certain condition. By this notation the authors also obtain the numbers of exceptional value of the Julia direction and Borel direction of algebriod functions are not more than 2 + [delta(x) (w)] here [x] implies an maximum integer number which does not exceed x. 展开更多
关键词 Algebriod functions deficient relations Nevanlinna directions
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ON THE NEVANLINNA DIRECTION OF ALGEBROID FUNCTIONS
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作者 张洪申 孙道椿 《Acta Mathematica Scientia》 SCIE CSCD 2012年第4期1441-1448,共8页
In this paper, we prove that for an algebroid function w(z), the singular direction argz = φ0, satisfying that for arbitrary ε(0 〈 ε 〈 2/π) and any given α ∈ C^^,limr→+∞ log τ/n(τ,φ0-ε,φ0+ε,w=a... In this paper, we prove that for an algebroid function w(z), the singular direction argz = φ0, satisfying that for arbitrary ε(0 〈 ε 〈 2/π) and any given α ∈ C^^,limr→+∞ log τ/n(τ,φ0-ε,φ0+ε,w=a)=+∞ holds with at most; 2v possible exceptional values of a, is the Ncvanlinna direction of w(z). 展开更多
关键词 algebroid function Nevanlinna direction algebroid function Nevanlinna direction
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DIRECT AND ADAPTIVE SLICING ON CAD MODEL OF IDEAL FUNCTIONAL MATERIAL COMPONENTS (IFMC) 被引量:3
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作者 XuDaoming JiaZhenyuan GuoDongming 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第1期139-144,共6页
A brand new direct and adaptive slicing approach is proposed, which canapparently improve the part accuracy and reduce the building time. At least two stages are includedin this operation: getting the crossing contour... A brand new direct and adaptive slicing approach is proposed, which canapparently improve the part accuracy and reduce the building time. At least two stages are includedin this operation: getting the crossing contour of the cutting plane with the solid part anddetermining the layer thickness. Apart from usual SPI algorithm, slicing of the solid model has itsspecial requirements. Enabling the contour line segments of the cross-section as long as possible isone of them, which is for improving manufacturing efficiency and is reached by adaptively adjustingthe step direction and the step size at every crossing point to obtain optimized secant height. Thelayer thickness determination can be divided into two phases: the geometry-based thicknessestimation and the material-based thickness verifying. During the former phase, the geometrytolerance is divided into two parts: a variety of curves are approximated by a circular arc, whichintroduces the first part, and the deviation error between the contour line in LM process and thecircular arc generates the second part. The latter phase is mainly verifying the layer thicknessestimated in the former stage and determining a new one if necessary. In addition, an example usingthis slicing algorithm is also illustrated. 展开更多
关键词 Rapid prototyping Ideal functional material components direct and adaptiveslicing Surface/plane intersection MARCHING
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Direction-dependent functions of physical properties for crystals and polycrystals
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作者 Mojia Huang Mengcheng Chen Tenglong Zheng 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第5期639-649,共11页
Some physical properties of crystals differ in direction n because crystal lattices are often anisotropic. A polycrystal is an aggregate of numerous tiny crystallites. Unless the polycrystal is an isotropic aggregate ... Some physical properties of crystals differ in direction n because crystal lattices are often anisotropic. A polycrystal is an aggregate of numerous tiny crystallites. Unless the polycrystal is an isotropic aggregate of crystallites, the physical properties of the polycrystal vary with n. The direction-dependent functions (DDF) for crystals and polycrystals are introduced to describe the variations of the physical properties in direction n. Until now there are few papers dealing systematically with relations between the DDF and the crystalline orientation distribution. Herein we give general expressions of the DDF for crystals and polycrystals. We discuss the applications of the DDF in describing the physical properties of crystals and polycrystals. 展开更多
关键词 direction-dependent function Orientation distribution function Physical properties of crystals and polycrystals
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Graph-Directed Coalescence Hidden Variable Fractal Interpolation Functions
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作者 Md. Nasim Akhtar M. Guru Prem Prasad 《Applied Mathematics》 2016年第4期335-345,共11页
Fractal interpolation function (FIF) is a special type of continuous function which interpolates certain data set and the attractor of the Iterated Function System (IFS) corresponding to a data set is the graph of the... Fractal interpolation function (FIF) is a special type of continuous function which interpolates certain data set and the attractor of the Iterated Function System (IFS) corresponding to a data set is the graph of the FIF. Coalescence Hidden-variable Fractal Interpolation Function (CHFIF) is both self-affine and non self-affine in nature depending on the free variables and constrained free variables for a generalized IFS. In this article, graph directed iterated function system for a finite number of generalized data sets is considered and it is shown that the projection of the attractors on is the graph of the CHFIFs interpolating the corresponding data sets. 展开更多
关键词 Iterated function System Graph-directed Iterated function System Fractal Interpolation functions Coalescence Hidden Variable FIFs
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Wideband direction-of-arrival estimation based on cubic spline function
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作者 Hongqi Yu David Day-Uei Li +2 位作者 Kun Zhang Jietao Diao Haijun Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第4期688-693,共6页
A new direction-of-arrival (DOA) estimation algorithm for wideband sources is introduced, The new method obtains the output of the virtual arrays in the signal bandwidth using cubic spline function interpolation tec... A new direction-of-arrival (DOA) estimation algorithm for wideband sources is introduced, The new method obtains the output of the virtual arrays in the signal bandwidth using cubic spline function interpolation techniques. The narrowband high- resolution algorithm is then used to get the DOA estimation. This technique does not require any preliminary knowledge of DOA angles. Simulation results demonstrate the effectiveness of the method. 展开更多
关键词 array signal processing wideband sources cubicspline function direction-of-arrival (DOA) estimation.
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On Singular Directions of Entire and Meromorphic Functions
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作者 常建明 宋国栋 任福尧 《Northeastern Mathematical Journal》 CSCD 2000年第4期379-382,共4页
关键词 entire and meromorphic function Martys direction GROWTH
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Self-Administered “Flow” Transcranial Direct Current Stimulation (tDCS) Depression Treatment in a Crisis Resolution & Home Treatment (CRT) Service: Functioning, and Health-Related Quality of Life Outcomes
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作者 Chris Griffiths Sherif Abdalla +1 位作者 Mark Mcconnochie Harmony Jiang 《Open Journal of Psychiatry》 2024年第S2期514-527,共14页
Background: Transcranial direct current stimulation (tDCS) has research evidence that it can reduce symptoms of depression. Flow FL-100 is a transcranial direct current stimulation (tDCS) device self-administered by a... Background: Transcranial direct current stimulation (tDCS) has research evidence that it can reduce symptoms of depression. Flow FL-100 is a transcranial direct current stimulation (tDCS) device self-administered by a patient at home in combination with a software application that delivers wellbeing behaviour therapy training. Purpose/aim: The purpose of this study was to investigate if Flow can be introduced to a Crisis Resolution & Home Treatment (CRT) service and the impact of Flow in treating depression. The study addresses the questions: 1) “what are the depression reliable improvement and remission rates?” and 2) “can Flow significantly reduce depressive symptoms and improve real world functioning (every-day, social and occupational functioning) and health-related quality of life?”. Methods: An open-label patient cohort design with no control group. Pre-intervention and 6-week follow-up intervention assessments using the participant self-report measures: Patient Health Questionnaire (PHQ-9), Work and Social Adjustment Scale (WSAS), and EuroQol five-dimension (EQ-5D-5L). Participants were 49 CRT patients, 19 males and 30 females, with an age range of 20 to 66 years, and average age of 42 years. Results: PHQ-9 reliable improvement and remission rates were 57.1% and 14.3%. PHQ-9 scores significantly improved, from 23.1 (SD 3.44) to 14.8 (SD 6.82) at 6 weeks, with a large effect size. PHQ-9 suicide/self-harm related question significantly improved from 2.51 (SD 0.77) to 1.08 (SD 1.17), with a large effect size. WSAS scores significantly improved, from 33.6 (SD 5.22) to 21.9 (SD 10.82) at 6 weeks, with a large effect size. EQ-5D-5L results showed significant improvements in the health index score, global assessment of health EQ-VAS from 34.2 (22.26) to 51.6 (24.95), and three EQ-5D-5L dimensions (“self-care”, “usual activity”, and “anxiety/depression”). Conclusion: A CRT service effectively integrated Flow tDCS treatment. Flow was beneficial in terms of improving functioning and quality of life and reducing depression symptoms and thoughts of suicide/self-harm. Flow FL100 tDCS and wellbeing behaviour therapy training could be offered through all CRT services to treat depression, reduce thoughts of suicide/self-harm, enable better functioning, and improve quality of life. 展开更多
关键词 DEPRESSION Quality of Life functionING Transcranial direct Current Stimulation (tDCS)
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Multi-function radar emitter identification based on stochastic syntax-directed translation schema 被引量:4
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作者 Liu Haijun Yu Hongqi +1 位作者 Sun Zhaolin Diao Jietao 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2014年第6期1505-1512,共8页
To cope with the problem of emitter identification caused by the radar words' uncertainty of measured multi-function radar emitters, this paper proposes a new identification method based on stochastic syntax-directed... To cope with the problem of emitter identification caused by the radar words' uncertainty of measured multi-function radar emitters, this paper proposes a new identification method based on stochastic syntax-directed translation schema(SSDTS). This method, which is deduced from the syntactic modeling of multi-function radars, considers the probabilities of radar phrases appearance in different radar modes as well as the probabilities of radar word errors occurrence in different radar phrases. It concludes that the proposed method can not only correct the defective radar words by using the stochastic translation schema, but also identify the real radar phrases and working modes of measured emitters concurrently. Furthermore, a number of simulations are presented to demonstrate the identification capability and adaptability of the SSDTS algorithm.The results show that even under the condition of the defective radar words distorted by noise,the proposed algorithm can infer the phrases, work modes and types of measured emitters correctly. 展开更多
关键词 Context-free Emitter identification Multi-function radar Signal processing Syntax-directed Translation schema
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The Effect of Non-Invasive Goal Directed Fluid Administration on Graft Function in Deceased Donor Renal Transplantation: A Pilot Study
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作者 Joseph R. Whiteley Jason M. Taylor +5 位作者 John J. Freely Jr. Thomas I. Epperson Laura Bell John L. Murray IV Charles F. Bratton William R. Hand 《Open Journal of Organ Transplant Surgery》 2016年第3期13-21,共9页
Background: Non-invasive goal directed fluid therapy during deceased donor renal transplant (CRT) may reduce the incidence of delayed graft function. Plethysmograph Variability Index (PVI) has been shown to predict fl... Background: Non-invasive goal directed fluid therapy during deceased donor renal transplant (CRT) may reduce the incidence of delayed graft function. Plethysmograph Variability Index (PVI) has been shown to predict fluid responsiveness during surgery. This pilot study evaluated the feasibility of goal directed fluid administration protocol based upon PVI studying the incidence of delayed graft function (DGF) in renal transplant recipients. Methods: Twenty patients underwent primary CRT. The Control group received intravenous fluid (IVF) at a calculated constant rate. The Treatment group received a baseline IVF infusion throughout the surgery. PVI values greater than 13% were treated with 250 ml boluses of IVF. Primary end point was DGF;total IVF administration and urinary biomarker NGAL levels were secondary endpoints. Results: Treatment group at every time point received significantly less IVF. There was no significant difference in incidence of DGF between the groups. 2 patients in the Control group and 6 in the Treatment group developed DGF. NGAL was not associated with the group assignment or total IVF given (p < 0.2). Conclusions: The effectiveness of goal directed fluid therapy with non-invasive dynamic parameters has not been validated in renal transplant surgery and larger prospective studies are needed to determine its utility in renal transplantation. 展开更多
关键词 Deceased Donor Renal Transplant Non-Invasive Goal directed Fluid Therapy Delayed Graft function Plethysmograph Variability Index
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Onsite-effects of dual-hemisphere versus conventional single-hemisphere transcranial direct current stimulation A functional MRI study
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作者 Yong Hyun Kwon Sung Ho Jang 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第24期1889-1894,共6页
We performed functional MRI examinations in six right-handed healthy subjects.During functional MRI scanning,transcranial direct current stimulation was delivered with the anode over the right primary sensorimotor cor... We performed functional MRI examinations in six right-handed healthy subjects.During functional MRI scanning,transcranial direct current stimulation was delivered with the anode over the right primary sensorimotor cortex and the cathode over the left primary sensorimotor cortex using dual-hemispheric transcranial direct current stimulation.This was compared to a cathode over the left supraorbital area using conventional single-hemispheric transcranial direct current stimulation. Voxel counts and blood oxygenation level-dependent signal intensities in the right primary sensorimotor cortex regions were estimated and compared between the two transcranial direct current stimulation conditions.Our results showed that dual-hemispheric transcranial direct current stimulation induced greater cortical activities than single-hemispheric transcranial direct current stimulation.These findings suggest that dual-hemispheric transcranial direct current stimulation may provide more effective cortical stimulation than single-hemispheric transcranial direct current stimulation. 展开更多
关键词 transcranial direct current stimulation dual-hemispheric stimulation cortical activation functional MRI primary sensorimotor cortex NEUROIMAGING regeneration neural regeneration
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Effect of Goal-Directed Fluid Therapy on Lung Function, Cognitive Function and Inflammatory Response in Patients Undergoing Radical Esophageal Cancer Surgery under One-Lung Ventilation
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作者 Jibo Zhao Yuanli Li +4 位作者 Dengyun Xia Xiaojia Sun Yuan Zhang Fulong Li Jinliang Teng 《Journal of Cancer Therapy》 2021年第9期487-496,共10页
<strong>Objective:</strong><span style="font-family:;" "=""><span style="font-family:Verdana;"> To explore the effects of goal-directed fluid therapy (GDFT) o... <strong>Objective:</strong><span style="font-family:;" "=""><span style="font-family:Verdana;"> To explore the effects of goal-directed fluid therapy (GDFT) on lung function, cognitive function and inflammatory response in patients undergoing radical esophageal cancer surgery under one-lung ventilation. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> Sixty-seven patients undergoing radical esophageal cancer surgery were divided into GDFT group</span></span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">(GDFT therapy) and control group</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">(conventional liquid therapy). The changes in patients</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;"> pulmonary function,</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">cognitive function and inflammatory response were evaluated. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> Both alveolar-arterial oxygen partial pressure difference</span></span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">[P(A-a)O</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">] and respiratory index</span></span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">(RI) increased at one-lung ventilation for 30 minutes (T</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">) and decreased at one-lung ventilation for 60 minutes</span></span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">(T</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">), and after surgery (T</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;">) in the two groups, and the GDFT group </span></span><span style="font-family:Verdana;">was</span><span style="font-family:Verdana;"> lower than the control group (P</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;"><</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">0.05);theoxygenation index (OI) of the two groups decreased at T</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">, T</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">, and T</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> compared with</span></span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">that at T</span><sub><span style="font-family:Verdana;">1</span></sub><span style="font-family:Verdana;"> (before one-lung ventilation), and the GDFT group was higher than the control group (P</span></span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;"><</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">0.05). At T</span><sub><span style="font-family:Verdana;">4</span></sub><span style="font-family:Verdana;"> and T</span><sub><span style="font-family:Verdana;">5</span></sub><span style="font-family:Verdana;">, the tumor necrosis factor </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;"> (TNF-</span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">), interleukin 6 (IL-6), central nervous system specific protein (S100</span><i><span style="font-family:Verdana;">β</span></i><span style="font-family:Verdana;">), and neuron specific enolase (NSE) in the GDFT group were lower compared to the control group (P</span></span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;"><</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">0.05), while interleukin-10 (IL-10) was higher compared to the control group (P</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;"><</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">0.05);the incidence of perioperative neurocognitive disorder (PND) in the GDFT group was lower than that in the control group (P</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;"><</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">0.05). </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> GDFT can help prevent lung injury during radical esophageal cancer surgery under one-lung ventilation, reduce the body</span></span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">s inflammatory response, and reduce the incidence of perioperative cognitive disorder to a certain extent.</span> 展开更多
关键词 Goal-directed Fluid Therapy Radical Resection of Esophageal Cancer Lung function Cognitive function Inflammatory Response
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重复经颅磁刺激和经颅直流电刺激对脑瘫患儿运动功能及步态影响的网状Meta分析
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作者 曹新燕 于子夫 +3 位作者 冷晓轩 高世爱 陈金慧 刘西花 《中国组织工程研究》 北大核心 2026年第6期1539-1548,共10页
目的:研究表明,重复经颅磁刺激和经颅直流电刺激对改善脑瘫患儿粗大运动功能具有积极作用。采用网状Meta分析方法评价重复经颅磁刺激和经颅直流电刺激对脑瘫患儿下肢运动功能及步态改善的临床疗效。方法:检索中国知网、万方、维普、Sino... 目的:研究表明,重复经颅磁刺激和经颅直流电刺激对改善脑瘫患儿粗大运动功能具有积极作用。采用网状Meta分析方法评价重复经颅磁刺激和经颅直流电刺激对脑瘫患儿下肢运动功能及步态改善的临床疗效。方法:检索中国知网、万方、维普、SinoMed、PubMed、Web of Science、Medline数据库,搜索关于重复经颅磁刺激与经颅直流电刺激改善脑瘫患儿下肢运动功能及步态的随机对照试验,检索时限均为数据库建库至2024-10-05。筛选文献、提取资料并评价纳入研究的偏倚风险,采用Stata 15.0软件进行网状Meta分析,使用GRADE证据分级系统进行质量评价。结果:最终纳入19篇研究,涉及常规治疗、高频重复经颅磁刺激、低频重复经颅磁刺激、阳极经颅直流电刺激4种治疗方案。网状Meta分析结果显示,与常规治疗相比,低频重复经颅磁刺激改善脑瘫患儿粗大运动功能方面的疗效最佳[MD=9.48,95%CI(6.61,12.34),P<0.05],在缓解痉挛方面,高频重复经颅磁刺激的疗效最佳[MD=-0.63,95%CI(-1.72,0.45),P<0.05],经颅直流电刺激改善脑瘫患儿踝关节活动度和步速方面的疗效最佳[MD=2.27,95%CI(1.37,3.17),P<0.05;MD=0.11,95%CI(0.05,0.17),P<0.05]。结论:现有临床证据表明,对于脑瘫患儿,在改善下肢粗大运动功能方面,低频重复经颅磁刺激展现出最佳疗效;对于降低肌痉挛程度,高频重复经颅磁刺激的效果更为显著;在步态改善方面,经颅直流电刺激则表现出明显优势。 展开更多
关键词 无创脑刺激 脑瘫 下肢运动功能 步态 经颅磁刺激 经颅直流电刺激 运动功能康复 工程化组织构建
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智能时代下正比例函数与固体压强的切割问题教学创新研究
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作者 张前瑾 刘宇 王悦 《计算机应用文摘》 2026年第1期22-25,共4页
针对正比例函数与固体压强切割问题中数理割裂和建模困难的现状,提出了一种融合智能学情分析、跨学科知识图谱、动态推理解题和实时评价反馈的教学创新模式。教学实验结果表明,与传统讲授模式相比,该模式显著提高了学生的函数建模能力... 针对正比例函数与固体压强切割问题中数理割裂和建模困难的现状,提出了一种融合智能学情分析、跨学科知识图谱、动态推理解题和实时评价反馈的教学创新模式。教学实验结果表明,与传统讲授模式相比,该模式显著提高了学生的函数建模能力和解题表现,综合成绩明显提升,数理融合意识得到了显著增强,验证了智能化技术在促进数学与物理深度整合中的应用价值。 展开更多
关键词 智能时代 正比例函数 固体压强 切割问题 教学创新
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基于电源车集群并网的电源车逆功率自动化保护技术研究
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作者 郭兴泉 纪业 +1 位作者 周晓光 汪志远 《电子设计工程》 2026年第2期96-100,共5页
针对电源车集群并网时,因电网侧与电源车侧电压幅值和频率差异引发逆功率,致使电源车部件受损及电力系统运行失稳的问题,研究基于电源车集群并网的逆功率自动化保护技术。设计电源车集群并网架构,分析电源车充放电时功率流向变化,依据... 针对电源车集群并网时,因电网侧与电源车侧电压幅值和频率差异引发逆功率,致使电源车部件受损及电力系统运行失稳的问题,研究基于电源车集群并网的逆功率自动化保护技术。设计电源车集群并网架构,分析电源车充放电时功率流向变化,依据功率流向判断逆功率产生的原因。在控制中心装配逆功率保护装置,用时间线性函数描述保护策略。实验结果表明,该技术能在0.1 s内改变电源侧输出功率,快速调整电网侧输出电压幅值与电流幅值,使电网侧频率偏离基准值的离散水平降至0.0801,电源车侧荷电偏离目标值的离散水平降至0.2251,可有效且快速地抑制电源车逆功率。 展开更多
关键词 电源车集群并网 逆功率 自动化保护 功率流向 时间线性函数
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A CLASS OF MULTIWAVELETS AND PROJECTED FRAMES FROM TWO-DIRECTION WAVELETS 被引量:3
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作者 李尤发 杨守志 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期285-300,共16页
This article aims at studying two-direction refinable functions and two-direction wavelets in the setting R^s, s 〉 1. We give a sufficient condition for a two-direction refinable function belonging to L^2(R^s). The... This article aims at studying two-direction refinable functions and two-direction wavelets in the setting R^s, s 〉 1. We give a sufficient condition for a two-direction refinable function belonging to L^2(R^s). Then, two theorems are given for constructing biorthogonal (orthogonal) two-direction refinable functions in L^2(R^s) and their biorthogonal (orthogonal) two-direction wavelets, respectively. From the constructed biorthogonal (orthogonal) two-direction wavelets, symmetric biorthogonal (orthogonal) multiwaveles in L^2(R^s) can be obtained easily. Applying the projection method to biorthogonal (orthogonal) two-direction wavelets in L^2(R^s), we can get dual (tight) two-direction wavelet frames in L^2(R^m), where m ≤ s. From the projected dual (tight) two-direction wavelet frames in L^2(R^m), symmetric dual (tight) frames in L^2(R^m) can be obtained easily. In the end, an example is given to illustrate theoretical results. 展开更多
关键词 Two-direction refinable functions two-direction wavelets MULTIWAVELETS waveletframes biothogonal (orthogonal) SYMMETRY projection method
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