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Triad-displaced ULAs configuration for non-circular sources with larger continuous virtual aperture and enhanced degrees of freedom
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作者 SHAIKH Abdul Hayee DANG Xiaoyu HUANG Daqing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期81-93,共13页
Non-uniform linear array(NULA)configurations are well renowned due to their structural ability for providing increased degrees of freedom(DOF)and wider array aperture than uniform linear arrays(ULAs).These characteris... Non-uniform linear array(NULA)configurations are well renowned due to their structural ability for providing increased degrees of freedom(DOF)and wider array aperture than uniform linear arrays(ULAs).These characteristics play a significant role in improving the direction-of-arrival(DOA)estimation accuracy.However,most of the existing NULA geometries are primarily applicable to circular sources(CSs),while they limitedly improve the DOF and continuous virtual aperture for noncircular sources(NCSs).Toward this purpose,we present a triaddisplaced ULAs(Tdis-ULAs)configuration for NCS.The TdisULAs structure generally consists of three ULAs,which are appropriately placed.The proposed antenna array approach fully exploits the non-circular characteristics of the sources.Given the same number of elements,the Tdis-ULAs design achieves more DOF and larger hole-free co-array aperture than its sparse array competitors.Advantageously,the number of uniform DOF,optimal distribution of elements among the ULAs,and precise element positions are uniquely determined by the closed-form expressions.Moreover,the proposed array also produces a filled resulting co-array.Numerical simulations are conducted to show the performance advantages of the proposed Tdis-ULAs configuration over its counterpart designs. 展开更多
关键词 direction-of-arrival(DOA)estimation sparse array non-circular source(NCS) sum co-array difference co-array degrees of freedom(DOF)
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Time-Domain Analysis of Body Freedom Flutter Based on 6DOF Equation
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作者 Zhehan Ji Tongqing Guo +2 位作者 Di Zhou Zhiliang Lu Binbin Lyu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期489-508,共20页
The reduced weight and improved efficiency of modern aeronautical structures result in a decreasing separation of frequency ranges of rigid and elastic modes.Particularly,a high-aspect-ratio flexible flying wing is pr... The reduced weight and improved efficiency of modern aeronautical structures result in a decreasing separation of frequency ranges of rigid and elastic modes.Particularly,a high-aspect-ratio flexible flying wing is prone to body freedomflutter(BFF),which is a result of coupling of the rigid body short-periodmodewith 1st wing bendingmode.Accurate prediction of the BFF characteristics is helpful to reflect the attitude changes of the vehicle intuitively and design the active flutter suppression control law.Instead of using the rigid body mode,this work simulates the rigid bodymotion of the model by using the six-degree-of-freedom(6DOF)equation.A dynamicmesh generation strategy particularly suitable for BFF simulation of free flying aircraft is developed.An accurate Computational Fluid Dynamics/Computational Structural Dynamics/six-degree-of-freedom equation(CFD/CSD/6DOF)-based BFF prediction method is proposed.Firstly,the time-domain CFD/CSD method is used to calculate the static equilibrium state of the model.Based on this state,the CFD/CSD/6DOF equation is solved in time domain to evaluate the structural response of themodel.Then combinedwith the variable stiffnessmethod,the critical flutter point of the model is obtained.This method is applied to the BFF calculation of a flyingwing model.The calculation results of the BFF characteristics of the model agree well with those fromthe modalmethod andNastran software.Finally,the method is used to analyze the influence factors of BFF.The analysis results show that the flutter speed can be improved by either releasing plunge constraint or moving the center ofmass forward or increasing the pitch inertia. 展开更多
关键词 Body freedom flutter time-domain CFD/CSD/6DOF method dynamic mesh generation strategy aeroelasticity
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Degree of Freedom Analysis for Holographic MIMO Based on a Mutual-Coupling-Compliant Channel Model
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作者 SUN Yunqi JIAN Mengnan +2 位作者 YANG Jun ZHAO Yajun CHEN Yijian 《ZTE Communications》 2024年第1期34-40,共7页
Degree of freedom(DOF)is a key indicator for spatial multiplexing layers of a wireless channel.Traditionally,the channel of a multiple-input multiple-output(MIMO)half-wavelength dipole array has a DOF that equals the ... Degree of freedom(DOF)is a key indicator for spatial multiplexing layers of a wireless channel.Traditionally,the channel of a multiple-input multiple-output(MIMO)half-wavelength dipole array has a DOF that equals the antenna number.However,recent studies suggest that the DOF could be less than the antenna number when strong mutual coupling is considered.We utilize a mutual-coupling-compliant channel model to investigate the DOF of the holographic MIMO(HMIMO)channel and give a upper bound of the DOF with strong mutual coupling.Our numerical simulations demonstrate that a dense array can support more DOF per unit aperture as compared with a half-wavelength MIMO system. 展开更多
关键词 channel model degree of freedom holographic MIMO mutual coupling
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Trimming the Degrees of Freedom via a K^(+) Flux Rectifier for Safe and Long‑Life Potassium‑Ion Batteries 被引量:2
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作者 Xianhui Yi Apparao MRao +1 位作者 Jiang Zhou Bingan Lu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第11期157-171,共15页
High degrees of freedom(DOF)for K^(+)movement in the electrolytes is desirable,because the resulting high ionic conductivity helps improve potassium-ion batteries,yet requiring support from highly free and flammable o... High degrees of freedom(DOF)for K^(+)movement in the electrolytes is desirable,because the resulting high ionic conductivity helps improve potassium-ion batteries,yet requiring support from highly free and flammable organic solvent molecules,seriously affecting battery safety.Here,we develop a K^(+)flux rectifier to trim K ion’s DOF to 1 and improve electrochemical properties.Although the ionic conductivity is compromised in the K^(+)flux rectifier,the overall electrochemical performance of PIBs was improved.An oxidation stability improvement from 4.0 to 5.9 V was realized,and the formation of dendrites and the dissolution of organic cathodes were inhibited.Consequently,the K||K cells continuously cycled over 3,700 h;K||Cu cells operated stably over 800 cycles with the Coulombic efficiency exceeding 99%;and K||graphite cells exhibited high-capacity retention over 74.7%after 1,500 cycles.Moreover,the 3,4,9,10-perylenetetracarboxylic diimide organic cathodes operated for more than 2,100 cycles and reached year-scale-cycling time.We fabricated a 2.18 Ah pouch cell with no significant capacity fading observed after 100 cycles. 展开更多
关键词 Electrolytes Degrees of freedom SAFE Coulombic efficiency Potassium-ion batteries
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Freedom EVO全自动酶联免疫前处理仪故障分析
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作者 周惠 李妙 周佳慧 《设备管理与维修》 2023年第12期81-82,共2页
全自动酶联免疫前处理是一种高自动化酶免诊断分析仪,用于检验科各类样品的液体处理工作。仪器在正常保养的情况下,由于标本量巨大、项目繁多,运行过程中不可避免地会出现故障。以Freedom EVO全自动酶联免疫前处理为例,分析总结使用过... 全自动酶联免疫前处理是一种高自动化酶免诊断分析仪,用于检验科各类样品的液体处理工作。仪器在正常保养的情况下,由于标本量巨大、项目繁多,运行过程中不可避免地会出现故障。以Freedom EVO全自动酶联免疫前处理为例,分析总结使用过程中出现的常见故障及解决方法,以尽快解决故障,提高检验质量和工作效率,确保设备长期有效的运行,供操作及维护人员参考。 展开更多
关键词 全自动酶联免疫前处理 freedom EVO 检测 保养 常见故障
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The Prisoner of“Freedom”:Cultural Displacement of Santosh in Naipaul’s In a Free State
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作者 LONG Hang-hang 《Journal of Literature and Art Studies》 2023年第5期357-361,共5页
In a Free State is a post-colonial novel written by Naipaul.“One out of Many”is one of the stories in this novel to explore the freedom of the culturally rootless.The protagonist,Santosh,lives under the collision be... In a Free State is a post-colonial novel written by Naipaul.“One out of Many”is one of the stories in this novel to explore the freedom of the culturally rootless.The protagonist,Santosh,lives under the collision between the Indian culture and American culture.In the“crevice”of two different cultures,he is deeply involved in the tumultuous and painful process of cultural displacement.His behaviors in cultural displacement can be divided into three stages.Firstly,he has experienced a“cultural shock”after his arrival in Washington,D.C.as a new comer.Secondly,after being fully exposed to the host culture and American style,he has experienced assimilation and absorption to be like an American.Finally when he escapes from his employer and chooses his own way of living,he finds that he is not free at all because he is confronted with an awkward cultural dilemma:he can neither return to his past life;nor can he aspire to a better future.The anxiety about the dislocation causes misery for his fate.As a result,he becomes a prisoner in an unfamiliar culture,and his“freedom”can only be a rootless“freedom”. 展开更多
关键词 Santosh In a Free State NAIPAUL cultural displacement freedom
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We Will Have More Freedom in the Next Century
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作者 Li Yinhe 《China Today》 2000年第1期8-9,共2页
关键词 We will Have More freedom in the Next Century
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The Conflict and Balance Between Intellectual Property Rights and Public Freedom of Information in the“Anti-circumvention Clause”
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作者 龚珊珊 严小翔 SHEN Jinjun(译) 《The Journal of Human Rights》 2023年第5期1115-1133,共19页
There is a long-standing conflict between intellectual property rights and public freedom of information.The continuous development of the“anti-circumvention clause”has caused the conflict to intensify.As a basic hu... There is a long-standing conflict between intellectual property rights and public freedom of information.The continuous development of the“anti-circumvention clause”has caused the conflict to intensify.As a basic human right,freedom of information is being gradually eroded by the expansion of intellectual property rights.The existing research mainly carries on the right balance from the negative protection path,but the positive protection path is more advantageous to realizing the public freedom of information and alleviates the conflict between the two kinds of rights.In practice,there are some problems in the application of the anti-circumvention clause,such as the legality of the aim,the division of the protected part,and the determination of the circumvention.This is mainly due to the lack of restrictions on technical measures,the failure to distinguish between“copyright protection”and“contact control”,and the offside and absence of administrative bodies in practice.We should protect public freedom of information by distinguishing the two measures of copyright protection and contact control and the two torts of access and use,increasing the restrictive conditions for the use of technical protection measures,and changing the functions of administrative supervision agencies. 展开更多
关键词 anti-circumvention clause intellectual property rights public information freedom balance of interests human rights
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The Kinematics Performance of Self-Propelled Full Freedom Filament in Wakes of Flow around Cylinder
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作者 Jiyao Yang Yun Liu Guoyi He 《Journal of Applied Mathematics and Physics》 2023年第10期2913-2922,共10页
In vortex streets, the kinematics performance of self-propelled full freedom filament is closely related to the length and the position of filaments in the flow field. In this paper, the changes of passive propulsion ... In vortex streets, the kinematics performance of self-propelled full freedom filament is closely related to the length and the position of filaments in the flow field. In this paper, the changes of passive propulsion velocity and pressure of full-degree-of-freedom filaments after cylindrical wake were analyzed by 15 sets of experiments when the length and position of filaments were changed. The results show that the propulsive velocity of the filament, it approximately increases first and then decreases with the filament length increasing, and the further away from the center of the cylinder, the smaller the propulsive velocity of the filament. In addition, the longer the filament length and the further it is from the center of the cylinder, the lower the pressure around the filament. Experiments show that filaments without energy input can obtain energy from the surrounding flow field to maintain self-propelled motion. Studying the influence of length and position on the kinematics of filaments is helpful to provide a reference for revealing the hydrodynamic mechanism on passive propulsion process and developing low resistance energy harvesting device in swimming fish movement. 展开更多
关键词 Length Position Change Full freedom Filaments Passive Propulsion
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康德文本中Willkür概念的诠释及启示 被引量:5
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作者 胡万年 《安徽师范大学学报(社会科学版)》 CSSCI 北大核心 2012年第4期428-434,共7页
Willkür是康德批判哲学的核心概念之一,是正确理解康德自由意志概念、乃至整个哲学体系的关键。基于文本学或诠释学研究方法,通过Wille和Gesinnung两个概念来诠释Willkür概念:首先,Willkür和Wille是同一个意志的两个方面... Willkür是康德批判哲学的核心概念之一,是正确理解康德自由意志概念、乃至整个哲学体系的关键。基于文本学或诠释学研究方法,通过Wille和Gesinnung两个概念来诠释Willkür概念:首先,Willkür和Wille是同一个意志的两个方面,Wille专指"纯粹实践理性的意志",即本体意义上的"自由意志"。Willkür是指"一般实践理性的意志",即既具有本体意义又具有现象意义的"自由意志"。其次,Gesinnung是Willkür进行自由抉择的根据,当我们追问Willkür的具体行为的根据时,我们便从Willkür过渡到Gesi-nnung。 展开更多
关键词 康德 自由 意志 决意 意向
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开源片上系统Freedom E310调试过程原理分析 被引量:1
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作者 雷思磊 王军 张海燕 《单片机与嵌入式系统应用》 2017年第9期19-22,28,共5页
Freedom E310是第一款基于RISC-V指令集架构的开源商业片上系统,可以依据具体应用场景对其进行深度定制,在介绍Freedom E310中与调试有关的模块、地址空间、控制状态寄存器之后,从原理上分析了halt、resume、step、断点设置等调试指令... Freedom E310是第一款基于RISC-V指令集架构的开源商业片上系统,可以依据具体应用场景对其进行深度定制,在介绍Freedom E310中与调试有关的模块、地址空间、控制状态寄存器之后,从原理上分析了halt、resume、step、断点设置等调试指令的实现过程。 展开更多
关键词 RISC-V freedom E310 JTAG
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开源片上系统Freedom E310调试方法研究 被引量:1
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作者 雷思磊 薛正 《单片机与嵌入式系统应用》 2017年第7期59-62,共4页
Freedom E310是第一款基于RISC—V指令集架构的开源商业片上系统,可以依据具体应用场景对其进行深度定制,在对Freedom E310及其Debug单元简单介绍的基础上,设计通过OpenOCD、J—Link建立Freedom E310调试环境,并进行了实际测试。
关键词 RISC—V freedom E310 JTAG
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Evaluation on Configuration Stiffness of Overconstrained 2R1T Parallel Mechanisms
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作者 Xuejian Ma Zhenghe Xu +3 位作者 Yundou Xu Yu Wang Jiantao Yao Yongsheng Zhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期62-82,共21页
Currently,two rotations and one translation(2R1T)three-degree-of-freedom(DOF)parallel mechanisms(PMs)are widely applied in five-DOF hybrid machining robots.However,there is a lack of an effective method to evaluate th... Currently,two rotations and one translation(2R1T)three-degree-of-freedom(DOF)parallel mechanisms(PMs)are widely applied in five-DOF hybrid machining robots.However,there is a lack of an effective method to evaluate the configuration stiffness of mechanisms during the mechanism design stage.It is a challenge to select appropriate 2R1T PMs with excellent stiffness performance during the design stage.Considering the operational status of 2R1T PMs,the bending and torsional stiffness are considered as indices to evaluate PMs'configuration stiffness.Subsequently,a specific method is proposed to calculate these stiffness indices.Initially,the various types of structural and driving stiffness for each branch are assessed and their specific values defined.Subsequently,a rigid-flexible coupled force model for the over-constrained 2R1T PM is established,and the proposed evaluation method is used to analyze the configuration stiffness of the five 2R1T PMs in the entire workspace.Finally,the driving force and constraint force of each branch in the whole working space are calculated to further elucidate the stiffness evaluating results by using the proposed method above.The obtained results demonstrate that the bending and torsional stiffness of the 2RPU/UPR/RPR mechanism along the x and y-directions are larger than the other four mechanisms. 展开更多
关键词 Parallel mechanism STIFFNESS Over-constrained Three degrees of freedom
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Dual-negative-objective Coordinated Control of Brushless Doubly Fed Induction Generator under Unbalanced Grid Voltage
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作者 Ming Cheng Zheng Cao Xiaoming Yan 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第3期347-355,共9页
This article proposes a dual-negative-objective coordinated control strategy for brushless doubly fed induction generator(BDFIG)based wind power generation system under unbalanced grid voltage.To alleviate the mechani... This article proposes a dual-negative-objective coordinated control strategy for brushless doubly fed induction generator(BDFIG)based wind power generation system under unbalanced grid voltage.To alleviate the mechanical stress and impaction on rotating shaft,the negative control objective(NCO)of machine side converter(MSC)is set to suppress the ripple of electromagnetic torque.While the NCO of grid side converter(GSC)is selected to suppress the oscillation of total output active power or the unbalanced degree of total output current for BDFIG generation system.In comparison with traditional single converter control scheme of the MSC or GSC,dual NCOs can be satisfied at the same time due to the enlarged freedom degree in the proposed improved coordinated control system for back-toback converters.The effectiveness of proposed control strategy is validated by simulation and experimental results on a dual-cagerotor BDFIG(DCR-BDFIG)prototype. 展开更多
关键词 Brushless doubly fed induction generator Dual-negative-objective freedom degree Unbalanced grid voltage
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Unification of Gravitational and Strong Interaction Fields Using Partial Gauge Symmetry
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作者 Young Hwan Yun Kiho Jang 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期515-533,共19页
We propose the new field potential by maintaining both the symmetry of the scalar gauge and the conservation law keeping N?ether’s theorem, while disregarding the symmetry of the vector gauge. The new potential forms... We propose the new field potential by maintaining both the symmetry of the scalar gauge and the conservation law keeping N?ether’s theorem, while disregarding the symmetry of the vector gauge. The new potential forms like the well-type potential where a particle behaves almost freely but is very hard to escape without external energy, which can be interpreted as local confinement and asymptotic freedom. By assuming a 2-dimensional metric tensor in 4-dimensional space-time, we suggest the existence of 3 kinds of particles that resemble QCD with 3 color charges. We also show that the mass term exists but comes to zero and derive the charge and spin values. We can regard the particle with this new potential as a gluon, and the interaction in this well-type potential as a strong interaction for the properties of mass, charge, spin, and its behavior. We suggest the eight-fold way with this new particle, which is similar to the existing method based on SU (3) symmetry. Even though the strong interaction has been analyzed in the standard model and string theory, we build a new consistent model based on the theory of relativity including Riemann geometry, and show the unification of gravitational and strong interactional field. 展开更多
关键词 Strong Interaction Gauge Symmetry RELATIVITY QCD CONFINEMENT Asymptotic freedom
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Cultivating the Human Rights Garden
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作者 RONNIE LINS 《China Today》 2024年第1期42-44,共3页
In the practice of advancing the cause of human rights,China has blazed a path of human rights development that is both consistent with the trend of the times and befits the nation’s conditions.WHEN contemplating hum... In the practice of advancing the cause of human rights,China has blazed a path of human rights development that is both consistent with the trend of the times and befits the nation’s conditions.WHEN contemplating human rights,the principle of individual freedom often comes to the forefront.The Chinese government’s perception,however,consists in the more organic concept of a metaphorical garden,wherein human rights flourish by virtue of China’s unique soil-its rich history,ancient culture,and political system.China,as a seasoned gardener,thus endeavors,under the leadership of President Xi Jinping,to develop human rights based on its national conditions. 展开更多
关键词 SEASON GARDEN freedom
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Probability Laws Derived from the Gamma Function
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作者 Lansana Toure Soumaila Conde 《Open Journal of Statistics》 2024年第1期106-118,共13页
Several densities or probability laws of continuous random variables derive from the Euler Gamma function. These laws form the basis of sampling theory, namely hypothesis testing and estimation. Namely the gamma, beta... Several densities or probability laws of continuous random variables derive from the Euler Gamma function. These laws form the basis of sampling theory, namely hypothesis testing and estimation. Namely the gamma, beta, and Student law, through the chi-square law and the normal law are all distributions resulting from applications of Euleur functions. 展开更多
关键词 Gamma Function Beta Function PROBABILITY Degree of freedom
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Levinas on the Ethics of the Other
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作者 HU Lijun PU Jingxin 《Philosophy Study》 2024年第1期16-21,共6页
The traditional mainstream of political philosophy establishes its thoughts on the subjectivity of“I”,which also formats its ethics of justice and freedom on the ground of selfness for itself and by itself.Political... The traditional mainstream of political philosophy establishes its thoughts on the subjectivity of“I”,which also formats its ethics of justice and freedom on the ground of selfness for itself and by itself.Political philosophers also incline to generalize and neutralize in labelling persons into the abstract concepts which ignore their particularity and diversity;as a result,this led to devastative consequence politically for the other,and also jeopardized the“I”.Hence Emmanuel Levinas provides his solution to this dilemma in an attempt to put the ethics of justice on the ground of the other.Justice for the other is the starting point for the political ethics.The other is the absolute infinity which cannot be encompassed by any conceptual generalization.It is otherness of the other that actually constitutes the selfness of“I”.The freedom of the other guarantees the freedom of“I”.Human being is initially ethical being.Justice for the other is the real foundation in securing justice for“I”.This mutual horizon of the other and I has primitive implication for the genuine ethics. 展开更多
关键词 the other I JUSTICE freedom ETHICS
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Empowerment in chronic wound care——exploring the scope for patient contribution
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作者 Benedikt Hackert Ewa Klara Stürmer Ulrich Weger 《Frontiers of Nursing》 2024年第1期1-16,共16页
Objective:In this study,we investigated the concept of empowerment in chronic wound care and propose to facilitate patient control by making use of degrees of freedom(DOF):that is,shaping of everyday wound care tasks ... Objective:In this study,we investigated the concept of empowerment in chronic wound care and propose to facilitate patient control by making use of degrees of freedom(DOF):that is,shaping of everyday wound care tasks initiated by patients and based on their wishes,mostly in terms of patients executing treatment steps,requesting or directing health care professionals to under take changes,or modifications of internal states.Methods:As a first step,we conducted a systematic literature search,followed by an inductive form of qualitative content analysis,which resulted in the identification of 5 dimensions as main elements of empowerment:education and shared decision making,adherence to self-care behaviors,responsibility and control,general call for empowerment,and DOF.However,the latter are noticeably absent in the literature.To investigate patients'freedom in shaping the wound care process,we conducted a second literature search.Results:A number of possibilities for patients to influence the wound care process could be identified,but experimental or clinical evidence about their effects is missing,their variety is limited,and they are only inadequately described.Conclusions:However,DOF should be an indispensable aspect of genuine empowerment,since they allow patients to occupy the role of the agent in the treatment process and give rise to the subjective experience of feeling empowered.Thus,in the third part,we develop a research proposal on how to investigate and include DOF in the clinical practice of wound care.Finally,limitations about implementations are discussed(e.g.,patients being reluctant to overcome their passive role,resulting in frustration for health care professionals). 展开更多
关键词 ADHERENCE chronic wounds control degrees of freedom EMPOWERMENT shared decision making
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African Warrior Women
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《ChinAfrica》 2024年第11期64-64,共1页
The book brings to light the powerful,often overlooked histories of female fighters across Africa.From ancient empires to modern resistance movements,this compelling narrative highlights the indomitable spirit of wome... The book brings to light the powerful,often overlooked histories of female fighters across Africa.From ancient empires to modern resistance movements,this compelling narrative highlights the indomitable spirit of women who transcended societal constraints to defend their communities,cultures,and freedoms.The book takes readers on a journey to discover the legendary queens of Africa. 展开更多
关键词 AFRICA SPIRIT freedom
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