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ON THE EXACT DEGREE OF APPROXIMATION BY HERMITE-FEJER INTERPOLATION BASED ON THE LAGUERRE ABSCISSAS
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作者 Shen Yunhai Sun Xiehua 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第4期405-410,共6页
For the nonpositive Hermite-Fejér interpolation based on the Laguerre abscissas, a pointwise two-sided estimate of the degree of approximation in the aleatoric interval [0, A] is first established.
关键词 Hermite-Fejér interpolation Laguerre abscissas two-sided estimate degree of approximation.
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DEGREE OF APPROXIMATION ASSOCIATED WITH SOME ELLIPTIC OPERATORS AND ITS APPLICATIONS 被引量:8
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作者 Xinlong Zhou(University of Duisburg, Germany) 《Analysis in Theory and Applications》 1995年第2期9-29,共21页
The Jackson-type estimates by using some elliptic operators will be achieved. These results will be used to characterize the regularity of some elliptic operators by means of the approximation degree and the saturatio... The Jackson-type estimates by using some elliptic operators will be achieved. These results will be used to characterize the regularity of some elliptic operators by means of the approximation degree and the saturation class of the multivariate Bernstein operators as well. 展开更多
关键词 degree of approximation ASSOCIATED WITH SOME ELLIPTIC OPERATORS AND ITS APPLICATIONS II ITS
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DEGREE OF APPROXIMATION BY SUPERPOSITIONS OF A SIGMOIDAL FUNCTION 被引量:16
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作者 Chen Debao (University of Texas at Austin,USA) 《Analysis in Theory and Applications》 1993年第3期17-28,共12页
In this paper we study the degree of approximation by superpositions of a sigmoidal function.We mainly consider the univariate case.If f is a continuous function,we prove that for any bounded sigmoidal function σ,d_... In this paper we study the degree of approximation by superpositions of a sigmoidal function.We mainly consider the univariate case.If f is a continuous function,we prove that for any bounded sigmoidal function σ,d_(n,σ)(f)≤‖σ‖ω(f,1/(n+1)).For the Heaviside function H(x),we prove that d_(n,H)(f)≤ω(f,1/(2(n+1))). If f is a continuous funnction of bounded variation,we prove that d_(n,σ)(f)≤‖σ‖/(n+1)V(f)and d_(n,H)(f)≤ 1/(2(n+1))V(f).For he Heaviside function,the coefficient 1 and the approximation orders are the best possible.We compare these results with the classical Jackson and Bernstein theorems,and make some conjec- tures for further study. 展开更多
关键词 degree of approximation BY SUPERPOSITIONS of A SIGMOIDAL FUNCTION
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Basic belief assignment approximations using degree of non-redundancy for focal element 被引量:3
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作者 Yi YANG Deqiang HAN Jean DEZERT 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第11期2503-2515,共13页
Dempster-Shafer evidence theory, also called the theory of belief function, is widely used for uncertainty modeling and reasoning. However, when the size and number of focal elements are large, the evidence combinatio... Dempster-Shafer evidence theory, also called the theory of belief function, is widely used for uncertainty modeling and reasoning. However, when the size and number of focal elements are large, the evidence combination will bring a high computational complexity. To address this issue,various methods have been proposed including the implementation of more efficient combination rules and the simplifications or approximations of Basic Belief Assignments(BBAs). In this paper,a novel principle for approximating a BBA into a simpler one is proposed, which is based on the degree of non-redundancy for focal elements. More non-redundant focal elements are kept in the approximation while more redundant focal elements in the original BBA are removed first. Three types of degree of non-redundancy are defined based on three different definitions of focal element distance, respectively. Two different implementations of this principle for BBA approximations are proposed including a batch and an iterative type. Examples, experiments, comparisons and related analyses are provided to validate proposed approximation approaches. 展开更多
关键词 BBA approximation Belief functions Evidence theory Focal element Non-redundancy
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A SHARP ESTIMATE ON THE DEGREE OF APPROXIMATION TO FUNCTIONS OF BOUNDED VARIATION BY CERTAIN OPERATORS 被引量:1
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作者 Vijay Gupta 《Analysis in Theory and Applications》 1995年第3期106-107,共2页
Recently Guo introduced integrated Meyer -Konig and Zeller operators and studied the rate of convergence for function of bounded variation. In this note we give a sharp estimate for these operators.
关键词 A SHARP ESTIMATE ON THE degree of approximation TO FUNCTIONS of BOUNDED VARIATION BY CERTAIN OPERATORS
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Degree of Approximation of Conjugate of Signals (Functions) by Lower Triangular Matrix Operator 被引量:1
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作者 Vishnu Narayan Mishra Huzoor H. Khan Kejal Khatri 《Applied Mathematics》 2011年第12期1448-1452,共5页
In the present paper, an attempt is made to obtain the degree of approximation of conjugate of functions (signals) belonging to the generalized weighted W(LP, ξ(t)), (p ≥ 1)-class, by using lower triangular matrix o... In the present paper, an attempt is made to obtain the degree of approximation of conjugate of functions (signals) belonging to the generalized weighted W(LP, ξ(t)), (p ≥ 1)-class, by using lower triangular matrix operator of conjugate series of its Fourier series. 展开更多
关键词 CONJUGATE FOURIER Series Generalized Weighted W(LP ξ(t))-Class degree of approximation and LOWER TRIANGULAR Matrix Means
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Statistical analysis on the validity of the cold plasma approximation for chorus waves based on Van Allen Probe observations and their effects on radiation belt electrons
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作者 AoJun Ren Jiang Yu +2 位作者 Jing Wang ZuZheng Chen XiaoMan Liu 《Earth and Planetary Physics》 EI CAS 2025年第1期159-170,共12页
Theoretical analysis has demonstrated that the dispersion relation of chorus waves plays an essential role in the resonant interaction and energy transformation between the waves and magnetospheric electrons.Previous ... Theoretical analysis has demonstrated that the dispersion relation of chorus waves plays an essential role in the resonant interaction and energy transformation between the waves and magnetospheric electrons.Previous quantitative analyses often simplified the chorus dispersion relation by using the cold plasma assumption.However,the applicability of the cold plasma assumption is doubtful,especially during geomagnetic disturbances.We here present a systematic statistical analysis on the validity of the cold plasma dispersion relation of chorus waves based on observations from the Van Allen Probes over the period from 2012 to 2018.The statistical results show that the observed magnetic field intensities deviate substantially from those calculated from the cold plasma dispersion relation and that they become more pronounced with an increase in geomagnetic activity or a decrease in background plasma density.The region with large deviations is mainly concentrated in the nightside and expands in both the radial and azimuthal directions as the geomagnetic activity increases or the background plasma density decreases.In addition,the bounce-averaged electron scattering rates are computed by using the observed and cold plasma dispersion relation of chorus waves.Compared with usage of the cold plasma dispersion relation,usage of the observed dispersion relation considerably lowers the minimum resonant energy of electrons and lowers the scattering rates of electrons above tens of kiloelectronvolts but enhances those below.Furthermore,these differences are more pronounced with the enhancement of geomagnetic activity or the decrease in background plasma density. 展开更多
关键词 chorus waves cold plasma approximation dispersion relations scattering rates
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Exceptional Set for Diophantine Approximation with Primes of Two Squares and Three Biquadrates
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作者 LIU Minmin ZHANG Min LI Jinjiang 《数学进展》 北大核心 2025年第1期18-36,共19页
Suppose thatλ_(1),λ_(2),λ_(3),λ_(4),λ_(5)are nonzero real numbers,not all of the same sign,andλ_(1)/λ_(2)is irrational and algebraic.Let V be a well-spaced sequence,δ>0.In this paper,it is proved that,for ... Suppose thatλ_(1),λ_(2),λ_(3),λ_(4),λ_(5)are nonzero real numbers,not all of the same sign,andλ_(1)/λ_(2)is irrational and algebraic.Let V be a well-spaced sequence,δ>0.In this paper,it is proved that,for anyε>0,the number of v∈V with v≤N such that the following inequality|λ_(1)p_(1)~2+λ_(2)p_(2)~2+λ_(3)p_(3)~4+λ_(4)p_(4)~4+λ_5p_5~4-v|<v^(-δ)has no solution in prime variables p_(1),p_(2),p_(3),p_(4),p_(5)does not exceed O(N^(29/32+2δ+ε)). 展开更多
关键词 Diophantine approximation exponential sum Davenport-Heilbronn method prime variable
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Ordering Degree Regulation of Pt_(2)NiCo Intermetallics for Efficient Oxygen Reduction Reaction
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作者 Chen-Hao Zhang Han-Yu Hu +3 位作者 Jun-Hao Yang Qian Zhang Chang Yang De-Li Wang 《电化学(中英文)》 北大核心 2025年第4期12-23,共12页
Alloying transition metals with Pt is an effective strategy for optimizing Pt-based catalysts toward the oxygen reduction reaction(ORR).Atomic ordered intermetallic compounds(IMC)provide unique electronic and geometri... Alloying transition metals with Pt is an effective strategy for optimizing Pt-based catalysts toward the oxygen reduction reaction(ORR).Atomic ordered intermetallic compounds(IMC)provide unique electronic and geometrical effects as well as stronger intermetallic interactions due to the ordered arrangement of metal atoms,thus exhibiting superior electrocata-lytic activity and durability.However,quantitatively analyzing the ordering degree of IMC and exploring the correlation between the ordering degree and ORR activity remains extremely challenging.Herein,a series of ternary Pt_(2)NiCo interme-tallic catalysts(o-Pt_(2)NiCo)with different ordering degree were synthesized by annealing temperature modulation.Among them,the o-Pt_(2)NiCo which annealed at 800℃for two hours exhibits the highest ordering degree and the optimal ORR ac-tivity,which the mass activity of o-Pt_(2)NiCo is 1.8 times and 2.8 times higher than that of disordered Pt_(2)NiCo alloy and Pt/C.Furthermore,the o-Pt_(2)NiCo still maintains 70.8%mass activity after 30,000 potential cycles.Additionally,the ORR activity test results for Pt_(2)NiCo IMC with different ordering degree also provide a positive correlation between the ordering degree and ORR activity.This work provides a prospective design direction for ternary Pt-based electrocatalysts. 展开更多
关键词 Fuel cell Oxygen reduction reaction ELECTROCATALYSIS Intermetallic compound Ordering degree
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The Degree of Approximation by(E,q)(C,α,β)Means in Orlicz Spaces
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作者 CHEN Lin WU Ga-ridi 《Chinese Quarterly Journal of Mathematics》 2024年第4期399-406,共8页
In this paper,we study the trigonometric approximation problems of functions which belong to the Lipαclass,the Lip(ξ(t))class,and the W(L_(M)^(*);ξ(t))class in Orlicz spaces by using the tools Hölder inequalit... In this paper,we study the trigonometric approximation problems of functions which belong to the Lipαclass,the Lip(ξ(t))class,and the W(L_(M)^(*);ξ(t))class in Orlicz spaces by using the tools Hölder inequality in Orlicz spaces,the second mean value theorem for integrals,and(E,q)(C,α,β)means etc.At the same time,we give the corresponding degree of approximation. 展开更多
关键词 Orlice space Trigonometric approximation degree of approximation
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Exploration and Practice of Innovative Talent Cultivation Models for Master's Degree Students in Ethnic Medicine:A Case Study of Guangxi University of Chinese Medicine
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作者 Haicheng WEN Ting LIU +2 位作者 Chen LIN Wei WEI Hao CHENG 《Asian Agricultural Research》 2025年第10期45-49,共5页
The cultivation of innovative talents has become the primary objective of talent development in colleges and universities and is also essential for the personal development of master's degree students.Ethnic medic... The cultivation of innovative talents has become the primary objective of talent development in colleges and universities and is also essential for the personal development of master's degree students.Ethnic medicine,a key discipline at Guangxi University of Chinese Medicine,aims to cultivate high-level master's degree talents who possess comprehensive qualities,strong innovative capabilities,and distinctive characteristics of Zhuang medicine.This program is designed to better serve the local economic development and social needs of Guangxi,thereby promoting the substantive advancement of higher education within traditional medical institutions. 展开更多
关键词 ETHNIC MEDICINE Innovative TALENT Master's degree student Ability cultivation
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Optimizing structural ordering degree to improve the mechanical reliability of metallic glasses
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作者 Shuang Su Wenjie Zhao +6 位作者 Xin Su Yagnesh Shadangi Zhishuai Jin Zhiliang Ning Yanming Zhang Jianfei Sun Yongjiang Huang 《Journal of Materials Science & Technology》 2025年第24期304-314,共11页
This study systematically investigates the influences of annealing treatment on the energy state,microstructure and macroscopic mechanical behaviors of metallic glasses(MGs).By reducing the energy state,the annealing ... This study systematically investigates the influences of annealing treatment on the energy state,microstructure and macroscopic mechanical behaviors of metallic glasses(MGs).By reducing the energy state,the annealing process significantly enhances the structural ordering degree and uniformity of MGs,thereby improving their overall mechanical reliability.Specifically,annealing promotes the formation of localized icosahedral short-range order,a structural signature that contributes to improved nanohardness and tensile strength.Furthermore,the release and redistribution of internal stress during annealing further optimize the internal stress state,significantly enhancing the fracture resistance and achieving reliable mechanical performance.This study not only elucidates the regulatory mechanisms of annealing on the microstructure of MGs but also provides theoretical support and experimental evidence for exploring MG materials with high strength and high fracture reliability. 展开更多
关键词 Metallic glasses ANNEALING Ordering degree Mechanical performance
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3I3S:Practice in the Software Engineering Degree Granting Program at Harbin Institute of Technology
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作者 Zhongjie Wang Tonghua Su +3 位作者 Shuang Yu Shuo Jin Yingxin Tian Yin Chen 《计算机教育》 2025年第3期71-79,共9页
In response to the current issues in the construction of software engineering(SE)degree granting program,such as insufficient resource integration,low level of internationalization,and inadequate quality control,we pr... In response to the current issues in the construction of software engineering(SE)degree granting program,such as insufficient resource integration,low level of internationalization,and inadequate quality control,we propose the Software Engineering Degree Granting Program Construction Practice Project at Harbin Institute of Technology(HIT).This project aims to explore new models for software talent cultivation,establish a superior SE degree granting program,and ultimately cultivate outstanding internationalized composite SE professionals to support the high-quality development of the national software industry.To this end,we design a distinctive overall construction idea and plan for the SE degree granting program,which are characterized by“3I3S:three highlights for specialized cultivation and strictness in three aspects to ensure quality control”.After years of practice and validation of the project at the School of Software at HIT,this project has proven effective in optimizing talent cultivation models,enhancing students’practical abilities,promoting international exchange and cooperation,advancing industry-education integration,and meeting industrial needs. 展开更多
关键词 Software engineering major degree granting program construction Quality assurance system
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Slip rate and locking degree of Haiyuan fault zone,northeastern Qinghai-Xizang plateau,based on refined block model and GPS data
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作者 Yang Liu Yuxuan Qiu +2 位作者 Jialiang Liu Yu Zhang Caijun Xu 《Geodesy and Geodynamics》 2025年第5期536-545,共10页
As a major fault in the northeastern Qinghai-Xizang Plateau,the Haiyuan fault zone is important for understanding the regional deformation.Aiming at the differences in the slip rate and locking degree obtained from di... As a major fault in the northeastern Qinghai-Xizang Plateau,the Haiyuan fault zone is important for understanding the regional deformation.Aiming at the differences in the slip rate and locking degree obtained from different studies,this study constructs a refined block model(including Qilian,Alxa,Ordos,Xining,Haiyuan,and Lanzhou blocks)and uses the grid search and simulated annealing methods to invert GPS data for slip rate and locking degree of the Haiyuan fault zone.The results are as follows:(1)The sinistral slip rates in the western,middle,and eastern segments are 4.93-5.22 mm/a,1.52-4.94 mm/a,and 0.43-1.18 mm/a,decreasing eastward on the whole,while the compression rates are 0.45-1.26 mm/a,0.58-2.62 mm/a,and3.52-4.48 mm/a,increasing eastward on the whole.(2)The locking depth of the western segment increases from about 5 km to about 20 km eastward;the middle segment decreases and then increases eastward;the eastern segment concentrates at about 20 km(PHI is about 0.86).(3)The slip deficit is relatively higher in the Lenglongling,Jinqianghe,Maomaoshan,and Liupanshan faults(averaging about 3.42 mm/a,4.16 mm/a,4.23 mm/a,and 3.43 mm/a within 20 km).(4)The Qilian,Alxa,Xining,Lanzhou,and Haiyuan blocks rotate clockwise,while the Ordos block rotates counterclockwise.Additionally,by comparing different block models,the Haiyuan block should be considered independently.The Haiyuan fault zone adjusts surrounding block movements and uplifts Liupanshan mountain tectonically.The results can provide important references for understanding the regional earthquake risk and deformation mechanism. 展开更多
关键词 Haiyuan fault zone Block model Locking degree Slip rate
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Six-Degree-of-Freedom Motion Analysis of High-Speed Craft Navigating through Variable Marine Environments
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作者 Xiaoyang Wu Wenchao Han +2 位作者 Min Kuang Xinqi Wang Wenhao Xie 《Fluid Dynamics & Materials Processing》 2025年第9期2201-2223,共23页
The dynamic behavior of high-speed craft navigating through variable sea states plays a pivotal role in ensuring maritime safety.However,many existing simulation approaches rely on linear or overly simplified represen... The dynamic behavior of high-speed craft navigating through variable sea states plays a pivotal role in ensuring maritime safety.However,many existing simulation approaches rely on linear or overly simplified representations of the marine environment,thereby limiting the fidelity of motion predictions.This study explores the motion characteristics of a 4.5-t high-speed vessel by conducting fully coupled numerical simulations using the STAR-CCM+software.The analysis considers both calm and varying sea conditions,incorporating fluctuations in wave height,wavelength,and wind speed to reflect more realistic operating scenarios.Simulation results reveal that the vessel’s hydrodynamic response is highly sensitive to changes in sea state.As conditions deteriorate,the free surface becomes increasingly complex,with higher wave amplitudes and more pronounced interactions between the waves generated by the vessel and those imposed by the external environment.These effects lead to significant increases in roll,pitch,heave,and sway motions,thereby imposing greater demands on the vessel’s dynamic stability and operational safety.Furthermore,both hydrodynamic resistance and propulsive thrust exhibit notable dependence on sea state and vessel speed.Total resistance generally increases with rougher sea conditions,while thrust tends to rise with increasing forward speed.Under calm or mildly disturbed waters,a Froude number(Fr)of 0.5 appears to offer an optimal balance for initiating and controlling primary motions such as roll,pitch,heave,and sway.Conversely,in more challenging conditions-such as those represented by a Sea State 3-effective motion control is better achieved at a higher Froude number of approximately 1.0. 展开更多
关键词 High-speed craft sea conditions six degrees of freedom free navigation
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On approximation of Bernstein-Stancu operators in movable interval
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作者 WAGN Feng-feng YU Dan-sheng 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第1期85-101,共17页
In the present paper,we obtain the converse results of approximation of a newly introduced genuine Bernstein-Durrmeyer operators in movable interval.We also get the moments properties of an auxiliary operator which ha... In the present paper,we obtain the converse results of approximation of a newly introduced genuine Bernstein-Durrmeyer operators in movable interval.We also get the moments properties of an auxiliary operator which has its own independent values.The moments of the auxiliary operators play important roles in establishing the main result(Theorem 4). 展开更多
关键词 Bernstein-Stancu operators movable interval approximation rates Voronovskaja's asymptotic estimate
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Mediating Effect of Medical Coping Styles in Patients with Chronic Pain between Pain Degree and Pain Catastrophe
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作者 Hui Qiang Yan Hua 《Journal of Clinical and Nursing Research》 2025年第11期409-419,共11页
Objective:To explore the relationship between pain degree and pain catastrophe and medical coping mode in patients with chronic pain.Methods:A visual analogue score scale,medical coping style questionnaire and pain ca... Objective:To explore the relationship between pain degree and pain catastrophe and medical coping mode in patients with chronic pain.Methods:A visual analogue score scale,medical coping style questionnaire and pain catastrophe scale were used to survey 200 patients in the pain department.Results:The average scores of pain degree of patients with chronic pain were(5.97±2.29),the average score of the total score of the Pain Catastrophe Scale was(21.21±11.56),and the average scores of facing,avoidance and surrender in the Medical Response Style Questionnaire were(17.93±3.4),(16.82±2.4),and(8.87±2.83),respectively.Pain degree was positively correlated with the yield dimension in pain catastrophe and medical coping(p<0.05).The yield dimension of medical coping was positively correlated with pain catastrophe(p<0.05).Medical coping methods played a partial mediating role between pain degree and pain catastrophe,and the mediating effect accounted for 21.59%of the total effect.Conclusion:The pain level of chronic pain patients can affect the level of pain catastrophe through medical coping,and clinical medical staff should guide patients to adopt positive coping methods to promote their healthy recovery. 展开更多
关键词 Chronic pain degree of pain Medical responses Catastrophic pain Mediating effects
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Effects of Standardized Bronchoscopic Interventional Therapy on Efficacy and Degree of Stenosis in Patients with Airway Stenosis
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作者 Jiahe Wang Wei Ji +2 位作者 Xuehui Mou Hongjuan Lyu Chen Chen 《Journal of Clinical and Nursing Research》 2025年第5期173-179,共7页
Objective:To analyze the treatment effect of standardized bronchoscopic interventional therapy(i.e.,interventional therapy)on airway stenosis.Methods:Forty patients with airway stenosis admitted to the hospital betwee... Objective:To analyze the treatment effect of standardized bronchoscopic interventional therapy(i.e.,interventional therapy)on airway stenosis.Methods:Forty patients with airway stenosis admitted to the hospital between September 2022 and September 2024 were selected and randomly divided into two groups using a random number table.The experimental group received interventional therapy,while the reference group received conventional treatment.The total effective rate,degree of airway stenosis,shortness of breath score,and lung function indicators were compared.Results:The total effective rate in the experimental group was higher than that in the reference group.The proportion of mild stenosis in the degree of airway stenosis was higher in the experimental group than in the reference group.The shortness of breath score was lower in the experimental group than in the reference group.The lung function indicators were better in the experimental group than in the reference group(P<0.05).Conclusion:Interventional therapy is effective for patients with airway stenosis,as it can reduce the degree of stenosis,improve symptoms of shortness of breath,and protect patients’lung function. 展开更多
关键词 Standardized bronchoscopic interventional therapy Airway stenosis Therapeutic effect degree of stenosis
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Theoretical Investigation on an Oscillating Wave Energy Converter in Different Degrees of Freedom in Front of a Seawall
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作者 WANG Yuhan DONG Sheng 《Journal of Ocean University of China》 2025年第2期289-302,共14页
The interaction between regular waves and an oscillating wave energy converter(WEC)in front of a vertical seawall is investigated using a 2D analytical model.A three-degree of freedom(DOF)WEC and a WEC hinged to the s... The interaction between regular waves and an oscillating wave energy converter(WEC)in front of a vertical seawall is investigated using a 2D analytical model.A three-degree of freedom(DOF)WEC and a WEC hinged to the seawall(constrained to pitch mode)are considered to examine the influence of the DOF of the WEC on the wave energy extraction performance.Results show that the piston-mode water resonance in the gap and the coupled WEC and water column resonant motion significantly influence the wave energy extraction efficiency.At low frequency,the case with a 3-DOF WEC has a broader high-efficiency bandwidth than that with a heaving WEC.However,3-DOF WEC exhibits worse performance at high frequencies.The frequency response of the wave energy capture width ratio(CWR)for the pitching WEC case shows a trimodal trend under the specified conditions.It showcases the best overall wave energy extraction performance in terms of the high-efficiency bandwidth.Furthermore,a parametric study indicates that the gap distance between the WEC and the seawall has tremendous effects on the CWR of both cases.As the position of the hinge point of the pitching WEC changes,the CWR at the low and high frequencies shows opposite trends. 展开更多
关键词 analytical model wave energy converter hinge connection multiple degrees of freedom gap resonance
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Detection of rock joints and opening degrees based on drilling parameters and moving average filter
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作者 Wenhao Yi Mingnian Wang +2 位作者 Qinyong Xia Honglin Shen Siguang Zhao 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第10期6130-6144,共15页
2The joint opening degree is a critical index for assessing the stability of jointed rock masses,which directly impacts the rock mass quality.It is also a key factor influencing the design of tunnel support structures... 2The joint opening degree is a critical index for assessing the stability of jointed rock masses,which directly impacts the rock mass quality.It is also a key factor influencing the design of tunnel support structures.Hammer and rotary drilling rigs,commonly employed as rock-breaking equipment in tunneling,inevitably encounter joints with varying opening degrees during construction.This research aims to enhance the sampling frequency of hammer and rotary drilling rigs and optimize the joint detection algorithm,thereby equipping these rigs with the capability to detect joint opening degrees.This paper develops high-frequency acquisition equipment for drilling parameters to realize millimeter-level data acquisition.Drilling experiments on jointed rock mass are conducted under conditions corresponding to joint opening degrees of 1 mm,3 mm,and 5 mm.The relationships among joint opening degree,drilling parameters,and width of rock failure region are investigated.A joint opening degree detection algorithm is proposed based on the drilling parameters and moving average filter.The results indicate that the curves of penetration velocity and rotary pressure along the drilling direction exhibit a three-segment distribution,i.e."stable segment-adjustment segment-stable segment".The variation curves of drilling parameters display a“velocity mountain”and a“pressure valley”in the failure region.The relative errors in joint opening degree estimation based on penetration velocity and rotary pressure range from 3.4%to 32%and from 6%to 35%,with average relative errors of 12.95%and 16.24%,respectively. 展开更多
关键词 Joint opening degree Drilling parameters Hammer and rotary drilling rigs Drilling experiment Data filtering
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