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Multimodal Signal Processing of ECG Signals with Time-Frequency Representations for Arrhythmia Classification
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作者 Yu Zhou Jiawei Tian Kyungtae Kang 《Computer Modeling in Engineering & Sciences》 2026年第2期990-1017,共28页
Arrhythmias are a frequently occurring phenomenon in clinical practice,but how to accurately dis-tinguish subtle rhythm abnormalities remains an ongoing difficulty faced by the entire research community when conductin... Arrhythmias are a frequently occurring phenomenon in clinical practice,but how to accurately dis-tinguish subtle rhythm abnormalities remains an ongoing difficulty faced by the entire research community when conducting ECG-based studies.From a review of existing studies,two main factors appear to contribute to this problem:the uneven distribution of arrhythmia classes and the limited expressiveness of features learned by current models.To overcome these limitations,this study proposes a dual-path multimodal framework,termed DM-EHC(Dual-Path Multimodal ECG Heartbeat Classifier),for ECG-based heartbeat classification.The proposed framework links 1D ECG temporal features with 2D time–frequency features.By setting up the dual paths described above,the model can process more dimensions of feature information.The MIT-BIH arrhythmia database was selected as the baseline dataset for the experiments.Experimental results show that the proposed method outperforms single modalities and performs better for certain specific types of arrhythmias.The model achieved mean precision,recall,and F1 score of 95.14%,92.26%,and 93.65%,respectively.These results indicate that the framework is robust and has potential value in automated arrhythmia classification. 展开更多
关键词 ELECTROCARDIOGRAM arrhythmia classification MULTIMODAL time-frequency representation
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Time evolution of angular momentum coherent state derived by virtue of entangled state representation and a new binomial theorem 被引量:1
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作者 Ji-Suo Wang Xiang-Guo Meng Hong-Yi Fan 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期253-256,共4页
We study how can an angular momentum coherent state |τ> keeps its form-invariant during time evolution governed by the Hamiltonian H = f(t)J++ f^*(t)J-+ g(t)Jz. We discuss this topic in the context of boson realiz... We study how can an angular momentum coherent state |τ> keeps its form-invariant during time evolution governed by the Hamiltonian H = f(t)J++ f^*(t)J-+ g(t)Jz. We discuss this topic in the context of boson realization of |τ>. By employing the entangled state representation |ζ> and deriving a new binomial theorem involving two-subscript Hermite polynomials, we derive the wave function <ζ|τ>, which turns out to be a single-subscript Hermite polynomial. Based on this result the maintenance of angular momentum coherent state during time evolution is examined, and the value of τ(t) is totally determined by the parameters involved in the Hamiltonian. 展开更多
关键词 invariance of angular momentum coherent STATE ENTANGLED STATE representation NEW BINOMIAL theorem time evolution
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FREUD-BUTZER-HAHN TYPE QUANTITATIVE THEOREMS FOR PROBABILISTIC REPRESENTATIONS OF(C_0)OPERATOR SEMIGROUPS 被引量:1
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作者 Chen Wenzhong (Xiamen University China)Zhou Mi (Xiamen Fisheries College,China) 《Analysis in Theory and Applications》 1993年第3期1-8,共8页
In this paper,we shall exploit the Freud method in the Classical operator approximation theory to im- prove known quantitative estimalions with an emphasis on Calculah' on the generic constants.
关键词 Th FREUD-BUTZER-HAHN TYPE QUANTITATIVE theoremS FOR PROBABILISTIC representationS OF C0)OPERATOR SEMIGROUPS
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Representation Theorem of Fuzzy Rough Set 被引量:3
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作者 舒兰 赵磊 《Journal of Electronic Science and Technology of China》 2004年第4期76-78,共3页
This paper gives the definition of λ-cut sets and studies the structure of fuzzy rough sets. Based on the concept of rough sets, this paper proposes the representation theorem of fuzzy rough sets.
关键词 rough set fuzzy sets fuzzy rough sets λ-cut sets representation theorem
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Convolution Theorem of Fractional Fourier Transformation Derived by Representation Transformation in Quantum Mechancis 被引量:1
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作者 FAN Hong-Yi HAO Ren LU Hai-Liang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第9期611-614,共4页
Based on our previous paper (Commun.Theor.Phys.39 (2003) 417) we derive the convolution theoremof fractional Fourier transformation in the context of quantum mechanics,which seems a convenient and neat way.Generalizat... Based on our previous paper (Commun.Theor.Phys.39 (2003) 417) we derive the convolution theoremof fractional Fourier transformation in the context of quantum mechanics,which seems a convenient and neat way.Generalization of this method to the complex fractional Fourier transformation case is also possible. 展开更多
关键词 fractional Fourier transformation convolution theorem quantum mechanical representation transform
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An elementary proof for the representation theorem of analytic isotropic tensor functions of a second-order tensor
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作者 Tianbo WANG Dinglin YANG +1 位作者 Chen LI Diwei SHI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2021年第5期747-754,共8页
Based on the Cayley-Hamilton theorem and fixed-point method,we provide an elementary proof for the representation theorem of analytic isotropic tensor functions of a second-order tensor in a three-dimensional(3D)inner... Based on the Cayley-Hamilton theorem and fixed-point method,we provide an elementary proof for the representation theorem of analytic isotropic tensor functions of a second-order tensor in a three-dimensional(3D)inner-product space,which avoids introducing the generating function and Taylor series expansion.The proof is also extended to any finite-dimensional inner-product space. 展开更多
关键词 representation theorem analytic tensor function fixed-point method
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The Representation Theorems of Conjugate Spaces of Some l^0({X_(i)}) Type F-Normed Spaces
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作者 Jianyong WANG 《Journal of Mathematical Research with Applications》 CSCD 2017年第5期591-602,共12页
In a paper published in Acta Mathematica Sinica(2016,59(4))we obtained some representation theorems for the conjugate spaces of some l^(0) type F-normed spaces.In this pa-per,for a sequence of normed spaces(X_(i)),we ... In a paper published in Acta Mathematica Sinica(2016,59(4))we obtained some representation theorems for the conjugate spaces of some l^(0) type F-normed spaces.In this pa-per,for a sequence of normed spaces(X_(i)),we study the representation problems of conjugate spaces of some l^(0)({X_(i)})type F-normed spaces,obtain the algebraic representation continued equalities(l^(0)({X_(i)}))^(*)=^(A)(c00^(0)({X_(i)}))^(*)=Ac00({X_(i)^(*)}),(l^(0)(X))^(*)=^(A)(c0^(0)(X))^(*)=^(A)(c00^(0)(X))^(*)=^(A)C00(X^(0)),and the topological representation((c00^(0)({X_(i)}))^(*),sw^(*))=c00^(0)({X_(i)^(*)}),where sw^(*)is the sequen-tial weak star topology.For the sequences of inner product spaces and number fields with the usual topology,the concrete forms of the basic representation theorems are obtained at last. 展开更多
关键词 l^0({X_(i)})type F-normed space locally convex space locally bounded space sequential weak star topology representation theorem
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Inversion formula and Parseval theorem for complex continuous wavelet transforms studied by entangled state representation
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作者 胡利云 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期263-267,共5页
In a preceding letter (2007 Opt. Lett. 32 554) we propose complex continuous wavelet transforms and found Laguerre-Gaussian mother wavelets family. In this work we present the inversion formula and Parseval theorem ... In a preceding letter (2007 Opt. Lett. 32 554) we propose complex continuous wavelet transforms and found Laguerre-Gaussian mother wavelets family. In this work we present the inversion formula and Parseval theorem for complex continuous wavelet transform by virtue of the entangled state representation, which makes the complex continuous wavelet transform theory complete. A new orthogonal property of mother wavelet in parameter space is revealed. 展开更多
关键词 Parseval theorem complex continuous wavelet transforms entangled state representation
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Application of Fourier Slice Theorem in Wigner Operator Theory and New Complete Representation
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作者 WANG Tong-Tong FAN Hong-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第11期829-831,共3页
By applying the Fourier slice theorem, Sθ(λ) =∫^∞-∞Pθ(t)e^-iλt=F(λcosθ,λsinθ),where Pθ(t) is a projection of f(x,p)=^∞∫∫-∞F(u,v)e^i(uz+up) dudv along lines of constant, to the Wigner ... By applying the Fourier slice theorem, Sθ(λ) =∫^∞-∞Pθ(t)e^-iλt=F(λcosθ,λsinθ),where Pθ(t) is a projection of f(x,p)=^∞∫∫-∞F(u,v)e^i(uz+up) dudv along lines of constant, to the Wigner operator we are naturally led to a projection operator (pure state), which results in a new complete representation. The Weyl orderimg formalism of the Wigner operator is used in the derivation. 展开更多
关键词 Wigner operator Fourier slice theorem new complete representation
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REMARKS ON THE REPRESENTATION THEOREM FOR RIESZ SPACES POSSESSING WEAK UNITS
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作者 熊洪允 《Transactions of Tianjin University》 EI CAS 1995年第1期10+6-10,共6页
The author obtains an algebraic version of the main result from his previous paper 'A characterization of Riesz spaces which are Riesz isomorphic to C(X) for some completely regular space X', and also studies... The author obtains an algebraic version of the main result from his previous paper 'A characterization of Riesz spaces which are Riesz isomorphic to C(X) for some completely regular space X', and also studies the relations among some conditions used therein. 展开更多
关键词 Riesz space weak unit representation
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MMHCA:Multi-feature representations based on multi-scale hierarchical contextual aggregation for UAV-view geo-localization 被引量:2
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作者 Nanhua CHEN Tai-shan LOU Liangyu ZHAO 《Chinese Journal of Aeronautics》 2025年第6期517-532,共16页
In global navigation satellite system denial environment,cross-view geo-localization based on image retrieval presents an exceedingly critical visual localization solution for Unmanned Aerial Vehicle(UAV)systems.The e... In global navigation satellite system denial environment,cross-view geo-localization based on image retrieval presents an exceedingly critical visual localization solution for Unmanned Aerial Vehicle(UAV)systems.The essence of cross-view geo-localization resides in matching images containing the same geographical targets from disparate platforms,such as UAV-view and satellite-view images.However,images of the same geographical targets may suffer from occlusions and geometric distortions due to variations in the capturing platform,view,and timing.The existing methods predominantly extract features by segmenting feature maps,which overlook the holistic semantic distribution and structural information of objects,resulting in loss of image information.To address these challenges,dilated neighborhood attention Transformer is employed as the feature extraction backbone,and Multi-feature representations based on Multi-scale Hierarchical Contextual Aggregation(MMHCA)is proposed.In the proposed MMHCA method,the multiscale hierarchical contextual aggregation method is utilized to extract contextual information from local to global across various granularity levels,establishing feature associations of contextual information with global and local information in the image.Subsequently,the multi-feature representations method is utilized to obtain rich discriminative feature information,bolstering the robustness of model in scenarios characterized by positional shifts,varying distances,and scale ambiguities.Comprehensive experiments conducted on the extensively utilized University-1652 and SUES-200 benchmarks indicate that the MMHCA method surpasses the existing techniques.showing outstanding results in UAV localization and navigation. 展开更多
关键词 Geo-localization Image retrieval UAV Hierarchical contextual aggregation Multi-feature representations
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Herglotz type Noether theorems of nonholonomic systems with generalized fractional derivatives 被引量:1
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作者 Yuan-Yuan Deng Yi Zhang 《Theoretical & Applied Mechanics Letters》 2025年第2期179-187,共9页
Fractional calculus is widely used to deal with nonconservative dynamics because of its memorability and non-local properties.In this paper,the Herglotz principle with generalized operators is discussed,and the Herglo... Fractional calculus is widely used to deal with nonconservative dynamics because of its memorability and non-local properties.In this paper,the Herglotz principle with generalized operators is discussed,and the Herglotz type equations for nonholonomic systems are established.Then,the Noether symmetries are studied,and the conserved quantities are obtained.The results are extended to nonholonomic canonical systems,and the Herglotz type canonical equations and the Noether theorems are obtained.Two examples are provided to demonstrate the validity of the methods and results. 展开更多
关键词 Nonholonomic system Herglotz principle Noether theorem Generalized operators
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On the representations of string pairs over virtual field
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作者 TAO Kun FU Chang-Jian 《四川大学学报(自然科学版)》 北大核心 2025年第5期1103-1108,共6页
Let F_(1)be the virtual field consisting of one element and(Q,I)a string pair.In this paper,we study the representations of string pairs over the virtual field F_(1).It is proved that an indecomposable F_(1)-represent... Let F_(1)be the virtual field consisting of one element and(Q,I)a string pair.In this paper,we study the representations of string pairs over the virtual field F_(1).It is proved that an indecomposable F_(1)-representation is either a string representation or a band representation by using the coefficient quivers.It is worth noting that for a given band and a positive integer,there exists a unique band representation up to isomorphism. 展开更多
关键词 string pair string representation band representation
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Advances in small molecule representations and AI-driven drug research:bridging the gap between theory and application 被引量:1
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作者 Junxi Liu Shan Chang +2 位作者 Qingtian Deng Yulian Ding Yi Pan 《Chinese Journal of Natural Medicines》 2025年第11期1391-1408,共18页
Artificial intelligence(AI)researchers and cheminformatics specialists strive to identify effective drug precursors while optimizing costs and accelerating development processes.Digital molecular representation plays ... Artificial intelligence(AI)researchers and cheminformatics specialists strive to identify effective drug precursors while optimizing costs and accelerating development processes.Digital molecular representation plays a crucial role in achieving this objective by making molecules machine-readable,thereby enhancing the accuracy of molecular prediction tasks and facilitating evidence-based decision making.This study presents a comprehensive review of small molecular representations and AI-driven drug discovery downstream tasks utilizing these representations.The research methodology begins with the compilation of small molecule databases,followed by an analysis of fundamental molecular representations and the models that learn these representations from initial forms,capturing patterns and salient features across extensive chemical spaces.The study then examines various drug discovery downstream tasks,including drug-target interaction(DTI)prediction,drug-target affinity(DTA)prediction,drug property(DP)prediction,and drug generation,all based on learned representations.The analysis concludes by highlighting challenges and opportunities associated with machine learning(ML)methods for molecular representation and improving downstream task performance.Additionally,the representation of small molecules and AI-based downstream tasks demonstrates significant potential in identifying traditional Chinese medicine(TCM)medicinal substances and facilitating TCM target discovery. 展开更多
关键词 Small molecular representation Drug-target interaction prediction Drug-target affinity prediction Drug property prediction De novo drug generation Traditional Chinese medicine
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The Paley-Wiener Theorem for General Weighted Hardy Spaces on Tube Domains
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作者 HUANG Yun ZHANG Dawei 《应用数学》 北大核心 2025年第3期841-849,共9页
In this paper,the Paley-Wiener theorem is extended to the analytic function spaces with general weights.We first generalize the theorem to weighted Hardy spaces Hp(0<p<∞)on tube domains by constructing a sequen... In this paper,the Paley-Wiener theorem is extended to the analytic function spaces with general weights.We first generalize the theorem to weighted Hardy spaces Hp(0<p<∞)on tube domains by constructing a sequence of L^(1)functions converging to the given function and verifying their representation in the form of Fourier transform to establish the desired result of the given function.Applying this main result,we further generalize the Paley-Wiener theorem for band-limited functions to the analytic function spaces L^(p)(0<p<∞)with general weights. 展开更多
关键词 Paley-Wiener theorem Fourier transform Weighted Hardy space Tube domain
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“Representation”的基本语义与中译名辨析
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作者 周建增 《文艺理论研究》 北大核心 2025年第2期55-67,141,共14页
“Representation”概念具有一个由多民族语言构成的词汇谱系。此一谱系的语义内核为替代,兼涉自我与他者,展现出一种在场的摇摆特性。以此观之,“再现”虽具备他者指涉内涵,却往往被视为模仿的另一种表述;再现还被用以翻译“reproduct... “Representation”概念具有一个由多民族语言构成的词汇谱系。此一谱系的语义内核为替代,兼涉自我与他者,展现出一种在场的摇摆特性。以此观之,“再现”虽具备他者指涉内涵,却往往被视为模仿的另一种表述;再现还被用以翻译“reproduction”,后者也是模仿的代名词。“表征”尽管突破了模仿的思路,试图涵盖“representation”的自我和他者面向;但是其古代汉语内涵和当代科技中文运用与“representation”原义不相凿枘。“表象”自古具有象征、代表和表示之义,能够涵盖“representation”的客体化和动作化意味。现代汉语翻译实践印证了这一点。所以,与再现、表征相比,表象更适合成为“representation”的主要中译名。将“representation”中译名拟定为表象,能够更好地释放出这一概念自身的理论潜能,以及它与中国文论的对话潜能。对“representation”概念进行语义学和中译名考察,乃尝试以还原、释义和正名之法,探讨异域概念的合适的汉语表达方式,进而寻求中西方文论对话、汇通的可能性。 展开更多
关键词 替代 再现 模仿 表征 表象
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A Metamodeling Approach to Enforcing the No-Cloning Theorem in Quantum Software Engineering
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作者 Dae-Kyoo Kim 《Computers, Materials & Continua》 2025年第8期2549-2572,共24页
Quantum software development utilizes quantum phenomena such as superposition and entanglement to address problems that are challenging for classical systems.However,it must also adhere to critical quantum constraints... Quantum software development utilizes quantum phenomena such as superposition and entanglement to address problems that are challenging for classical systems.However,it must also adhere to critical quantum constraints,notably the no-cloning theorem,which prohibits the exact duplication of unknown quantum states and has profound implications for cryptography,secure communication,and error correction.While existing quantum circuit representations implicitly honor such constraints,they lack formal mechanisms for early-stage verification in software design.Addressing this constraint at the design phase is essential to ensure the correctness and reliability of quantum software.This paper presents a formal metamodeling framework using UML-style notation and and Object Constraint Language(OCL)to systematically capture and enforce the no-cloning theorem within quantum software models.The proposed metamodel formalizes key quantum concepts—such as entanglement and teleportation—and encodes enforceable invariants that reflect core quantum mechanical laws.The framework’s effectiveness is validated by analyzing two critical edge cases—conditional copying with CNOT gates and quantum teleportation—through instance model evaluations.These cases demonstrate that the metamodel can capture nuanced scenarios that are often mistaken as violations of the no-cloning theorem but are proven compliant under formal analysis.Thus,these serve as constructive validations that demonstrate the metamodel’s expressiveness and correctness in representing operations that may appear to challenge the no-cloning theorem but,upon rigorous analysis,are shown to comply with it.The approach supports early detection of conceptual design errors,promoting correctness prior to implementation.The framework’s extensibility is also demonstrated by modeling projective measurement,further reinforcing its applicability to broader quantum software engineering tasks.By integrating the rigor of metamodeling with fundamental quantum mechanical principles,this work provides a structured,model-driven approach that enables traditional software engineers to address quantum computing challenges.It offers practical insights into embedding quantum correctness at the modeling level and advances the development of reliable,error-resilient quantum software systems. 展开更多
关键词 METAMODELING no-cloning theorem quantum software software engineering
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Scaling Rule,Energy Distribution and Energy Level Analysis for Morse Oscillator by Virtue of Hermann-Feynman Theorem
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作者 Zhi-Long Wan Jun-Hua Chen Hong-Yi Fan 《Chinese Journal of Chemical Physics》 2025年第3期368-372,I0109,共6页
We propose the scaling rule of Morse oscillator,based on this rule and by virtue of the Her-mann-Feymann theorem,we respectively obtain the distribution of potential and kinetic ener-gy of the Morse Hamiltonian.Also,w... We propose the scaling rule of Morse oscillator,based on this rule and by virtue of the Her-mann-Feymann theorem,we respectively obtain the distribution of potential and kinetic ener-gy of the Morse Hamiltonian.Also,we derive the exact upper limit of physical energy level.Further,we derive some recursive relations for energy matrix elements of the potential and other similar operators in the context of Morse oscillator theory. 展开更多
关键词 Morse oscillator Scaling rule Hermann-Feynman theorem
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From a Preeminent Metaphysical Poet to a Half-orphan Poet:Mis/representation of John Donne as a Full-blown Metaphysical Poet
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作者 Eugene Ngezem 《Philosophy Study》 2025年第6期369-372,共4页
The purpose of this article is to depart from the conventional belief that John Donne,a vibrant 17th-century writer,is a full-blown metaphysical poet as widely claimed while also acknowledging the poetic ingenuity of ... The purpose of this article is to depart from the conventional belief that John Donne,a vibrant 17th-century writer,is a full-blown metaphysical poet as widely claimed while also acknowledging the poetic ingenuity of John Donne.While Donne’s poetry is rich in matter and manner,and his poems are caked in wit,intellectual superiority,and apt exploration of telling themes,dressing him fully in borrowed robes seems a stretch.Some of Donne’s poems,without a shred of doubt,contain flavors of metaphysical poetry,but the term“metaphysical”seems to be unsuitable for poems such as“A Valediction:Forbidding Mourning”. 展开更多
关键词 metaphysical metaphysics mis/representation exaggeration half-orphan full-blown half-baked ingenuity
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Integrating species diversity, ecosystem services, climate and ecological stability helps to improve spatial representation of protected areas for quadruple win
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作者 Hui Dang Yihe Lü +2 位作者 Xiaofeng Wang Yunqi Hao Bojie Fu 《Geography and Sustainability》 2025年第1期47-57,共11页
Establishing and maintaining protected areas is a pivotal strategy for attaining the post-2020 biodiversity target. The conservation objectives of protected areas have shifted from a narrow emphasis on biodiversity to... Establishing and maintaining protected areas is a pivotal strategy for attaining the post-2020 biodiversity target. The conservation objectives of protected areas have shifted from a narrow emphasis on biodiversity to encompass broader considerations such as ecosystem stability, community resilience to climate change, and enhancement of human well-being. Given these multifaceted objectives, it is imperative to judiciously allocate resources to effectively conserve biodiversity by identifying strategically significant areas for conservation, particularly for mountainous areas. In this study, we evaluated the representativeness of the protected area network in the Qin ling Mountains concerning species diversity, ecosystem services, climate stability and ecological stability. The results indicate that some of the ecological indicators are spatially correlated with topographic gradient effects. The conservation priority areas predominantly lie in the northern foothills, the southeastern, and southwestern parts of the Qinling Mountain with areas concentrated at altitudes between 1,500-2,000 m and slopes between 40°-50° as hotspots. The conservation priority areas identified through the framework of inclusive conservation optimization account for 22.9 % of the Qinling Mountain. Existing protected areas comprise only 6.1 % of the Qinling Mountain and 13.18 % of the conservation priority areas. This will play an important role in achiev ing sustainable development in the region and in meeting the post-2020 biodiversity target. The framework can advance the different objectives of achieving a quadruple win and can also be extended to other regions. 展开更多
关键词 Protected areas Nature conservation Ecological representation Qinling Mountains Spatial planning
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