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Hypersingular parameterized Marcinkiewicz integrals with variable kernels on Sobolev and Hardy-Sobolev spaces 被引量:2
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作者 CHEN Jie-cheng YU Xiao ZHANG Yan-dan WANG Hui 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第4期420-430,共11页
Let α≥ 0 and 0 〈 ρ ≤ n/2, the boundedness of hypersingular parameterized Marcinkiewicz integrals μΩ,α^ρ with variable kernels on Sobolev spaces Lα^ρ and HardySobolev spaces Hα^ρ is established.
关键词 parameterized Marcinkiewicz integral variable kernel hardy-sobolev space L^α-Dini condition
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WANDERING SUBSPACES OF THE HARDY-SOBOLEV SPACES OVER D^n
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作者 肖杰胜 曹广福 《Acta Mathematica Scientia》 SCIE CSCD 2016年第5期1467-1473,共7页
In this paper, we show that for log(2/3)/2log2≤ β ≤1/2, suppose S is an invariant subspace of the Hardy-Sobolev spaces H_β~2(D^n) for the n-tuple of multiplication operators(M_(z_1),...,M_(z_n)). If(M_(z_1)|S,...,... In this paper, we show that for log(2/3)/2log2≤ β ≤1/2, suppose S is an invariant subspace of the Hardy-Sobolev spaces H_β~2(D^n) for the n-tuple of multiplication operators(M_(z_1),...,M_(z_n)). If(M_(z_1)|S,..., M_(z_n)|S) is doubly commuting, then for any non-empty subset α = {α_1,..., α_k} of {1,..., n}, W_α~S is a generating wandering subspace for M_α|_S =(M_(z_(α_1))|_S,..., M_(z_(α_k))|_S), that is, [W_α~S]_(M_(α |S))= S, where W_α~S=■(S ■ z_(α_i)S). 展开更多
关键词 wandering subspace invariant subspace Beurling's theorem hardy-sobolev space doubly commuting
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GENERALIZED FORELLI-RUDIN TYPE OPERATORS BETWEEN SEVERAL FUNCTION SPACES ON THE UNIT BALL OF C^(N) 被引量:1
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作者 Xuejun ZHANG Yuting GUO +1 位作者 Hongxin CHEN Pengcheng TANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1301-1326,共26页
In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order t... In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order to prove the main results,we first give some bidirectional estimates for several typical integrals. 展开更多
关键词 Forelli-Rudin type operator L^(p q s k)(B_(n))space BOUNDEDNESS unit ball
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BIG HANKEL OPERATORS ON HARDY SPACES OF STRONGLY PSEUDOCONVEX DOMAINS
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作者 陈伯勇 江良英 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期789-809,共21页
In this article,we investigate the(big) Hankel operator H_(f) on the Hardy spaces of bounded strongly pseudoconvex domains Ω in C^(n).We observe that H_(f ) is bounded on H~p(Ω)(1 <p <∞) if f belongs to BMO a... In this article,we investigate the(big) Hankel operator H_(f) on the Hardy spaces of bounded strongly pseudoconvex domains Ω in C^(n).We observe that H_(f ) is bounded on H~p(Ω)(1 <p <∞) if f belongs to BMO and we obtain some characterizations for Hf on H^(2)(Ω) of other pseudoconvex domains.In these arguments,Amar's L^(p)-estimations and Berndtsson's L^(2)-estimations for solutions of the ■_(b)-equation play a crucial role.In addition,we solve Gleason's problem for Hardy spaces H^(p)(Ω)(1 ≤p≤∞) of bounded strongly pseudoconvex domains. 展开更多
关键词 Hankel operator Hardy space Bergman space pseudoconvex domain
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PRODUCT TYPE OPERATORS ACTING BETWEEN WEIGHTED BERGMAN SPACES AND BLOCH TYPE SPACES
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作者 Zuoling LIU Hasi WULAN 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1327-1336,共10页
For analytic functions u,ψin the unit disk D in the complex plane and an analytic self-mapφof D,we describe in this paper the boundedness and compactness of product type operators T_(u,ψ,φ)f(z)=u(z)f(φ(z))+ψ(z)f... For analytic functions u,ψin the unit disk D in the complex plane and an analytic self-mapφof D,we describe in this paper the boundedness and compactness of product type operators T_(u,ψ,φ)f(z)=u(z)f(φ(z))+ψ(z)f'(φ(z)),z∈D,acting between weighted Bergman spaces induced by a doubling weight and a Bloch type space with a radial weight. 展开更多
关键词 COMPACTNESS BOUNDEDNESS Bloch type space product type operator weighted Bergman space
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Butterfly taxonomic and functional diversity in the urban green spaces of Hefei city
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作者 Haicong Zeng Yan Zhu +5 位作者 Junyao Zhang Chenliang Li Jian Zhang Hui Liu Jianan Wang Dexian Zhao 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期47-62,共16页
Urbanization has profound impacts on ecological environments. Green spaces are a vital component of urban ecosystems and play a crucial role in maintaining ecological balance and enhancing sustainability. This study a... Urbanization has profound impacts on ecological environments. Green spaces are a vital component of urban ecosystems and play a crucial role in maintaining ecological balance and enhancing sustainability. This study aimed to investigate the community composition characteristics of butterflies in urban green spaces within the context of rapid urbanization. Simultaneously, it explored the status and differences in butterfly taxonomic diversity, functional diversity, and functional traits among different types of urban green spaces, regions, and urban gradients to provide relevant insights for further improving urban green space quality and promoting biodiversity conservation. We conducted a year-long survey of 80 green spaces across different urban regions and ring roads within Hefei City, Anhui Province, with monthly sampling intervals over 187 transects. A total of 4822 butterflies, belonging to 5 families, 17 subfamilies, 40 genera, and 55 species were identified. The species richness, Shannon, Simpson, functional richness, and Rao's quadratic entropy indices of butterflies in urban park green spaces were all significantly higher than those in residential and street green spaces(P < 0.05). Differences in butterfly diversity and functional traits among different urban regions and ring roads were relatively minor, and small-sized, multivoltine, and long flying duration butterflies dominated urban green spaces. Overall, these spaces offer more favorable habitats for butterflies. However, some residential green spaces and street green spaces demonstrate potential for butterfly conservation. 展开更多
关键词 Urban green space planning Rapid urbanization Butterfly functional traits Green space types Urban biodiversity
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MAXIMAL FUNCTION CHARACTERIZATIONS OF HARDY SPACES ASSOCIATED WITH BOTH NON-NEGATIVE SELF-ADJOINT OPERATORS SATISFYING GAUSSIAN ESTIMATES AND BALL QUASI-BANACH FUNCTION SPACES
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作者 林孝盛 杨大春 +1 位作者 杨四辈 袁文 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期484-514,共31页
Assume that L is a non-negative self-adjoint operator on L^(2)(ℝ^(n))with its heat kernels satisfying the so-called Gaussian upper bound estimate and that X is a ball quasi-Banach function space onℝ^(n) satisfying som... Assume that L is a non-negative self-adjoint operator on L^(2)(ℝ^(n))with its heat kernels satisfying the so-called Gaussian upper bound estimate and that X is a ball quasi-Banach function space onℝ^(n) satisfying some mild assumptions.Let HX,L(ℝ^(n))be the Hardy space associated with both X and L,which is defined by the Lusin area function related to the semigroup generated by L.In this article,the authors establish various maximal function characterizations of the Hardy space HX,L(ℝ^(n))and then apply these characterizations to obtain the solvability of the related Cauchy problem.These results have a wide range of generality and,in particular,the specific spaces X to which these results can be applied include the weighted space,the variable space,the mixed-norm space,the Orlicz space,the Orlicz-slice space,and the Morrey space.Moreover,the obtained maximal function characterizations of the mixed-norm Hardy space,the Orlicz-slice Hardy space,and the Morrey-Hardy space associated with L are completely new. 展开更多
关键词 Hardy space ball quasi-Banach function space Gaussian upper bound estimate non-negative self-adjoint operator maximal function
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A DERIVATIVE-HILBERT OPERATOR ACTING FROM LOGARITHMIC BLOCH SPACES TO BERGMAN SPACES
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作者 Shanli YE Yun XU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1916-1930,共15页
Letμbe a positive Borel measure on the interval[0,1).The Hankel matrix■with entriesμn,k=μn+k,whereμn=■[0,1)tndμ(t),induces,formally,the operator■where■is an analytic function in.We characterize the measuresμ... Letμbe a positive Borel measure on the interval[0,1).The Hankel matrix■with entriesμn,k=μn+k,whereμn=■[0,1)tndμ(t),induces,formally,the operator■where■is an analytic function in.We characterize the measuresμfor which■is bounded(resp.,compact)operator from the logarithmic Bloch space■into the Bergman space■,where 0≤α<∞,0<p<∞.We also characterize the measuresμfor which■is bounded(resp.,compact)operator from the logarithmic Bloch space■into the classical Bloch space■. 展开更多
关键词 derivative-Hilbert operator logarithmic Bloch space Carleson measure
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SUMS OF DUAL TOEPLITZ PRODUCTS ON THE ORTHOGONAL COMPLEMENTS OF FOCK-SOBOLEV SPACES
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作者 陈泳 Young Joo Lee 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期810-822,共13页
We consider dual Toeplitz operators on the orthogonal complements of the FockSobolev spaces of all nonnegative real orders.First,for symbols in a certain class containing all bounded functions,we study the problem of ... We consider dual Toeplitz operators on the orthogonal complements of the FockSobolev spaces of all nonnegative real orders.First,for symbols in a certain class containing all bounded functions,we study the problem of when an operator which is finite sums of the dual Toeplitz products is compact or zero.Next,for bounded symbols,we construct a symbol map and exhibit a short exact sequence associated with the C^(*)-algebra generated by all dual Toeplitz operators with bounded symbols. 展开更多
关键词 dual Toeplitz operators Fock-Sobolev spaces symbol map
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Weighted multilinear p-adic Hardy operators and commutators on p-adic Herz-type spaces
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作者 MA Teng ZHOU Jiang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期554-570,共17页
In this paper,we introduce the weighted multilinear p-adic Hardy operator and weighted multilinear p-adic Ces`aro operator,we also obtain the boundedness of these two operators on the product of p-adic Herz spaces and... In this paper,we introduce the weighted multilinear p-adic Hardy operator and weighted multilinear p-adic Ces`aro operator,we also obtain the boundedness of these two operators on the product of p-adic Herz spaces and p-adic Morrey-Herz spaces,the corresponding operator norms are also established in each case.Moreover,the boundedness of commutators of these two operators with symbols in central bounded mean oscillation spaces and Lipschitz spaces on p-adic Morrey-Herz spaces are also given. 展开更多
关键词 Morrey-Herz spaces weighted multilinear p-adic Hardy operator COMMUTATORS operator norms
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Integrity and Size of Green Spaces Are Critical for the Functional Di-versity of Birds:Evidence from the Eastern and Northwestern Regions of China
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作者 GONG Lingxuan WANG Lili +5 位作者 YAO Yao WU Linyi WANG Su TAN Bingchang YUAN Hongdan HU Runan 《Chinese Geographical Science》 SCIE CSCD 2024年第6期1073-1089,共17页
Urbanization often changes bird species richness and affects the functional diversity.Therefore,understanding these changes helps city planners improve green space design and land use planning.Our study used multiple ... Urbanization often changes bird species richness and affects the functional diversity.Therefore,understanding these changes helps city planners improve green space design and land use planning.Our study used multiple datasets to explore the effects of land-scape patterns and natural environments on the functional diversity of birds in urban parks and campuses in the eastern and northwest-ern regions of China.Firstly,we used the data to calculate birds of the functional richness(FRic),functional evenness(FEve),and func-tional divergence(FDiv)of 68 urban spaces in the eastern and northwestern regions of China.Further,we established generalized linear models of natural factors,human factors,and functional diversity.Results showed more bird species with unique traits were in the north-western region.This may be because the earlier urbanization in the eastern region filtered out urban-sensitive species,leaving behind urban adapters.Moreover,we found that the fractal dimension index was the most significant positive factor of FRic in the eastern re-gion but the most significant negative factor of FDiv.Elevation was the most significant negative influence factor of FEve in the eastern region,but it was the most potent positive influence factor of FRic in the northwestern region.Population density had a significant posit-ive effect on FDiv in the northwestern region.However,green space areas significantly negatively impacted FEve in the northwestern region.In addition,birds in parks in both regions had more functional traits than those on campuses,possibly because of the larger green space in parks,which may contain more fragments of native vegetation and reduce human interference.Our study suggests that pre-serving more original vegetation and reducing human disturbance in cities can increase the functional diversity of urban birds and im-prove urban ecosystem functions. 展开更多
关键词 BIRDS functional diversity green space the eastern and northwestern regions of China
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TOEPLITZ OPERATORS BETWEEN WEIGHTED BERGMAN SPACES OVER THE HALF-PLANE
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作者 Lixia FENG Yan LI +1 位作者 Zhiyu WANG Liankuo ZHAO 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1707-1720,共14页
In this paper,by characterizing Carleson measures,we investigate a class of bounded Toeplitz operator between weighted Bergman spaces with Békolléweights over the half-plane for all index choices.
关键词 weighted Bergman spaces Békolléweights Carleson measure Toeplitz operators
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THE BOUNDEDNESS OF OPERATORS ON WEIGHTED MULTI-PARAMETER LOCAL HARDY SPACES
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作者 丁卫 汤彦 朱月萍 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期386-404,共19页
Though atomic decomposition is a very useful tool for studying the boundedness on Hardy spaces for some sublinear operators,untill now,the boundedness of operators on weighted Hardy spaces in a multi-parameter setting... Though atomic decomposition is a very useful tool for studying the boundedness on Hardy spaces for some sublinear operators,untill now,the boundedness of operators on weighted Hardy spaces in a multi-parameter setting has been established only by almost orthogonality estimates.In this paper,we mainly establish the boundedness on weighted multi-parameter local Hardy spaces via atomic decomposition. 展开更多
关键词 weighted multi-parameter local Hardy spaces atomic decomposition BOUNDEDNESS inhomogeneous Journéclass
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The Dual of the Two-Variable Exponent Amalgam Spaces (Lq(),lp())(Ω)
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作者 Sambourou Massinanke Sékou Coulibaly Mamadou Traore 《Journal of Applied Mathematics and Physics》 2024年第2期383-431,共49页
Wiener amalgam spaces are a class of function spaces where the function’s local and global behavior can be easily distinguished. These spaces are ex-tensively used in Harmonic analysis that originated in the work of ... Wiener amalgam spaces are a class of function spaces where the function’s local and global behavior can be easily distinguished. These spaces are ex-tensively used in Harmonic analysis that originated in the work of Wiener. In this paper: we first introduce a two-variable exponent amalgam space (L<sup>q</sup><sup>()</sup>,l<sup>p</sup><sup>()</sup>)(Ω). Secondly, we investigate some basic properties of these spaces, and finally, we study their dual. 展开更多
关键词 Amalgam spaces Variable Exponent Lebesgue spaces Dual of a Vector space
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Motion and Special Relativity in Complex Spaces
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作者 Jerzy K. Filus 《Journal of Applied Mathematics and Physics》 2024年第1期330-361,共32页
A natural extension of the Lorentz transformation to its complex version was constructed together with a parallel extension of the Minkowski M<sup>4</sup> model for special relativity (SR) to complex C<... A natural extension of the Lorentz transformation to its complex version was constructed together with a parallel extension of the Minkowski M<sup>4</sup> model for special relativity (SR) to complex C<sup>4</sup> space-time. As the [signed] absolute values of complex coordinates of the underlying motion’s characterization in C<sup>4</sup> one obtains a Newtonian-like type of motion whereas as the real parts of the complex motion’s description and of the complex Lorentz transformation, all the SR theory as modeled by M<sup>4</sup> real space-time can be recovered. This means all the SR theory is preserved in the real subspace M<sup>4</sup> of the space-time C<sup>4</sup> while becoming simpler and clearer in the new complex model’s framework. Since velocities in the complex model can be determined geometrically, with no primary use of time, time turns out to be definable within the equivalent theory of the reduced complex C<sup>4</sup> model to the C<sup>3</sup> “para-space” model. That procedure allows us to separate time from the (para)space and consider all the SR theory as a theory of C<sup>3</sup> alone. On the other hand, the complex time defined within the C<sup>3</sup> theory is interpreted and modeled by the single separate C<sup>1</sup> complex plane. The possibility for application of the C<sup>3</sup> model to quantum mechanics is suggested. As such, the model C<sup>3</sup> seems to have unifying abilities for application to different physical theories. 展开更多
关键词 Special Relativity Complex space and Time Models and Dramatic SR Simplification Complex Time and space Separation Complex Time Interpretation
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Micro Renewal of Public Spaces in Communities Surrounding Colleges and Universities
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作者 ZHANG Ningning 《Journal of Landscape Research》 2024年第5期64-67,共4页
The community located around colleges and universities is a place where university students and community residents engage in production and life together.Due to the influence of colleges and universities,these commun... The community located around colleges and universities is a place where university students and community residents engage in production and life together.Due to the influence of colleges and universities,these communities have spontaneously formed various other functions,resulting in the disorderly development of the entire space and a lack of effective guidance and control.With the development of colleges and universities,problems within the community are gradually increasing.These factors affect the spatial quality of the communities,as well as the environmental atmosphere of colleges and universities,and cause damage to the spatial environment of the entire region.By sorting out the issues between universities and surrounding communities,the development of universities is linked with that of communities,and a path of cooperation and win-win development is sought. 展开更多
关键词 Surrounding communities of colleges and universities Public space Micro renewal
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Identity of Urban Spaces: Assessment and Evaluation
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作者 Elham Madadi-Kandjani 《Journal of Civil Engineering and Architecture》 2024年第5期254-259,共6页
As a major symbol of civilization,the city was built by man for his security and comfort.It is not only a settlement,but also an urban development which has been identified with the spirit that has been breathed into ... As a major symbol of civilization,the city was built by man for his security and comfort.It is not only a settlement,but also an urban development which has been identified with the spirit that has been breathed into the community.Urban identity which is also known as collective identity,has gained meaning through the content of objective manifestation and the creation of flashbacks,citizens’memories and mental associations.That is what makes urban dwellers become citizens.Although the identity of the city is a result of civic culture,it still has an influence on the process of citizenship and can also be a reason for developing criteria related to the participation and assessment of its inhabitants.According to the view that identity is a set of traits and characteristics that distinguishes the dignity of a person and a society from other individuals and communities,a city becomes characterized and independent by adhering to these criteria.Despite the importance of identity as one of the richest qualitative aspects of urban life that gives meaning and fulfilment to the human quiddity,this complicated and expanded concept has still not been seriously considered,especially in relation to urban spaces.In fact,identity in architecture and urban spaces has recently diminished,since the main focus lies on building spaces for optimized profit and not for high quality living areas.In this research paper,parameters affecting urban identity are evaluated,and strategies and guidelines to promote these parameters are finally presented. 展开更多
关键词 IDENTITY urban spaces quality of life urban development strategies
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Creating Tender Spaces
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作者 ZHANG YAGE 《ChinAfrica》 2024年第12期34-35,共2页
China is pushing to develop child-friendly cities Li Jingyu,a 10-year-old student from Peixin Primary School in Beijing’s Dongcheng District,has been an art enthusiast for six years.On 3 November,one of her creations... China is pushing to develop child-friendly cities Li Jingyu,a 10-year-old student from Peixin Primary School in Beijing’s Dongcheng District,has been an art enthusiast for six years.On 3 November,one of her creations was exhibited at the capital’s Today Art Museum. 展开更多
关键词 spaces CREATION friendly
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THREE KINDS OF DENTABILITIES IN BANACH SPACES AND THEIR APPLICATIONS
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作者 张子厚 周晶 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期445-454,共10页
In this paper,we study some dentabilities in Banach spaces which are closely related to the famous Radon-Nikodym property.We introduce the concepts of the weak^(*)-weak denting point and the weak^(*)-weak^(*)denting p... In this paper,we study some dentabilities in Banach spaces which are closely related to the famous Radon-Nikodym property.We introduce the concepts of the weak^(*)-weak denting point and the weak^(*)-weak^(*)denting point of a set.These are the generalizations of the weak^(*)denting point of a set in a dual Banach space.By use of the weak^(*)-weak denting point,we characterize the very smooth space,the point of weak^(*)-weak continuity,and the extreme point of a unit ball in a dual Banach space.Meanwhile,we also characterize an approximatively weak compact Chebyshev set in dual Banach spaces.Moreover,we define the nearly weak dentability in Banach spaces,which is a generalization of near dentability.We prove the necessary and sufficient conditions of the reflexivity by nearly weak dentability.We also obtain that nearly weak dentability is equivalent to both the approximatively weak compactness of Banach spaces and the w-strong proximinality of every closed convex subset of Banach spaces. 展开更多
关键词 weak^(*)-weak denting point nearly weak dentability very smooth space point of weak^(*)-weak continuity extreme point approximatively weak compactness w-strong proximinality REFLEXIVITY
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Attributes of Domestic Spaces for Contemporary Habitation-A Secondary Publication
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作者 Silvina Barraud Caffaratti 《Journal of Architectural Research and Development》 2024年第1期84-92,共9页
The domestic space can be defined as the sphere that articulates the needs for subjective containment and contextual stimuli.In this sense,questions arise about the indispensable attributes that spaces must possess fo... The domestic space can be defined as the sphere that articulates the needs for subjective containment and contextual stimuli.In this sense,questions arise about the indispensable attributes that spaces must possess for this articulation to take place adequately.Architecture,as the discipline in charge of satisfying the specific spatial needs of those who inhabit these spaces and,in a broader sense,as a concrete contribution to society,must address this relationship in all its complexity and generate concrete responses that incorporate the appropriate spatial attributes during the design processes.The design processes that shape living spaces confront this dialectic,and the manner in which they do so brings identity and character to them.It is believed that the higher the level of variables that are contemplated and weighted,the greater the adequacy of spaces to the changing dynamics of the people who inhabit them.This article focuses on a thorough analysis of these spatial attributes,in parallel to the definition of each one as a particular condition for design,based on their conceptualization,breakdown,and articulation.Conceptually,the following attributes are addressed:flexibility,adaptability,variability,versatility,multiplicity,plurality,integrality,gradualness,incrementality,progressiveness,independence,connectivity,intimacy,and privacy.Each of these attributes is valued as a contribution to creating adequate habitability in contextual terms,with consideration to possible integrations and combinations. 展开更多
关键词 Attributes Domestic space Design processes
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