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Utilisation of green urban space for food sufficiency and the realisation of the sustainable development goals-UK stakeholders perspective
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作者 Alex Opoku Anna Duff +1 位作者 Moohammed Wasim Yahia Samuel Ekung 《Geography and Sustainability》 CSCD 2024年第1期13-18,共6页
The exponential growth of food demand due to the increasing global population has the potential to seriously threaten the quality and quantity of food supplies due to climate change.This study explores the utilisation... The exponential growth of food demand due to the increasing global population has the potential to seriously threaten the quality and quantity of food supplies due to climate change.This study explores the utilisation of green urban spaces for achieving food self-sufficiency by investigating the extent to which sustainable urban farms could be used to reduce the consumption of imported produce in the UK.It also examines urban farming stakeholders'perspective on how food self-sufficiency can help realise the SDGs especially SDG 2(Zero hunger)and SDG 13(Climate action).The study adopts a mixed method approach through a survey with 115 respondents and semi-structured interviews conducted with 12 respondents from 4 different urban farming stakeholder groups.The findings of this study presented a strong correlation between stakeholders who had concerns about where their food came from and the carbon footprint of imported produce.The research shows that,urban farms will no doubt play a vital role in the future of food security in our cities/communities and that the SDGs could be realised through sustainable urban farms implemented within the relevant planning regulations/policies. 展开更多
关键词 Cities Food sufficiency Green urban space Urban farms SDGS
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Seasonal implications for taxonomic sufficiency to simplify M-AMBI methodology in the coastal area adjacent to a eutrophic estuary
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作者 Chenman Yang Hongjun Song +3 位作者 Yi Sun Pengfei Xie Yuan Liu Hongjun Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第10期108-116,共9页
Taxonomic sufficiency(TS)refers to identifying taxa to a taxonomic level sufficient to detect community changes in stressed environments and may provide a cost-effective approach in routine monitoring programs.However... Taxonomic sufficiency(TS)refers to identifying taxa to a taxonomic level sufficient to detect community changes in stressed environments and may provide a cost-effective approach in routine monitoring programs.However,there is still limited information regarding the seasonal impact of applying TS and its implications for the ecological quality evaluation in the estuarine ecosystem.This study investigated the relationship between the multivariate-AZTI’s Marine Biotic Index(M-AMBI)and environmental variables in three seasons(i.e.,spring,summer,and autumn)in the Liaohe River Estuary.We tested the reliability of TS for simplifying the M-AMBI methodology.The results showed that family and genus level data could reproduce the spatial-temporal patterns of community structure at the species level.The M-AMBI values showed a consistent spatial distribution pattern in all sampling seasons,with a decreasing trend with the increasing distance from the estuary mouth.Both genus and family level data performed nearly as well as species level in detecting the seasonal variations of pollutants(i.e.,nutrients and total organic content).The family level M-AMBI was feasible to discern stress in the Liaohe River Estuary because of the high aggregation ratios at different taxonomic levels in all sampling seasons.These findings suggest that applying taxonomic sufficiency based on the M-AMBI provides an efficient approach for evaluating ecological quality in the Liaohe River Estuary. 展开更多
关键词 M-AMBI ecological quality MACROFAUNA taxonomic sufficiency EUTROPHICATION Liaohe River Estuary
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Sufficiency and Duality for Nondif ferentiable Multiobjective Fractional Programming Problems with (Φ,ρ,α)-V-Invexity 被引量:2
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作者 闫春雷 杨舒先 《Journal of Donghua University(English Edition)》 EI CAS 2017年第2期178-183,共6页
A new concept of(Φ,ρ,α)-V-invexity for differentiable vector-valued functions is introduced,which is a generalization of differentiable scalar-valued(Φ,ρ)-invexity.Based upon the(Φ,ρ,α)-V-invex functions,suffi... A new concept of(Φ,ρ,α)-V-invexity for differentiable vector-valued functions is introduced,which is a generalization of differentiable scalar-valued(Φ,ρ)-invexity.Based upon the(Φ,ρ,α)-V-invex functions,sufficient optimality conditions and MondWeir type dual theorems are derived for a class of nondifferentiable multiobjective fractional programming problems in which every component of the objective function and each constraint function contain a term involving the support function of a compact convex set. 展开更多
关键词 nondifferentiable multiobjective fractional programming efficiency ρ α)-V-invexity sufficiency DUALITY
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Sufficiency and Deficiency Indices of Soil Available Zinc for Rice in the Alluvial Soil of the Coastal Yellow Sea 被引量:1
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作者 WEI Yi chang BAI You lu +6 位作者 JIN Ji yun YANG Li ping YAO Zheng XU Si xin Luo Guo an SONG Wei ZHU Chun mei 《Rice science》 SCIE 2007年第3期223-228,共6页
To determine the sufficiency and deficiency indices of soil available Zn by the Agro Services International (ASI) method (ASI-Zn) for Zn fertilizer recommendation in rice production in the alluvial soil of the coa... To determine the sufficiency and deficiency indices of soil available Zn by the Agro Services International (ASI) method (ASI-Zn) for Zn fertilizer recommendation in rice production in the alluvial soil of the coastal Yellow Sea, the relationship between relative rice yield and soil available ASI-Zn concentration was analyzed from a ten-field experiment with various soil test classes ranging from low to high fertility in 2005 and 2006, and nine Zn fertilizer application rates (0, 7.5 15, 22.5, 30, 37.5, 45, 52.5 and 60 kg Zn/ha) arranged at random with three replications in each field. There was a significant quadratic relationship between soil available ASI-Zn and rice yield, and a significant linear relationship between soil available ASI-Zn concentration and Zn fertilization rate. For rice variety Wuyujing 3, soil available ASI-Zn was deficient when the value was at lower than 1 mg Zn/L, low at 1 to 2 mg Zn/L, sufficient at 1 to 2 mg Zn/L, excessive at higher than 7.5 mg Zn/L. Thus, Zn fertilizer recommendation could be done according to the sufficiency and deficiency indices of soil ASI-Zn. For most of alluvial soils of the coastal Yellow Sea in the study, the available ASI-Zn was lower than 1 mg Zn/L, and then the optimum application rate of Zn fertilizer was about 20 kg Zn/ha. 展开更多
关键词 Agro Services International method coastal alluvial soil RICE soil available zinc sufficiency index deficiency index fertilizer recommendation yield
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Sufficiency Economy for Sustainable Human Resource Development in Tourism Business
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作者 Khewika Sukiam 《Journal of Tourism and Hospitality Management》 2018年第1期17-22,共6页
The purpose of this paper is to suggest the concept of sufficiency economy philosophy to be used in tourism business,especially in human resource development(HRD).This paper covers the analysis and synthesis from lite... The purpose of this paper is to suggest the concept of sufficiency economy philosophy to be used in tourism business,especially in human resource development(HRD).This paper covers the analysis and synthesis from literature review,the meaning of sufficiency economy philosophy,sustainable development and human resource.The result has shown that the sufficiency economy philosophy is a measure of well-being(Nothing can be developed sustainably like HRD.Tourism business is a service product that depends on human resources).That is the reason why the sufficiency economy philosophy should be implemented for sustainable HRD in tourism business. 展开更多
关键词 sufficiency ECONOMY SUSTAINABLE human resource development(HRD) TOURISM BUSINESS
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LINEAR SUFFICIENCY IN THE GENERAL GAUSS-MARKOV MODEL
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作者 Liu JinshanDept. of Math., Wuyi Univ.,Guangdong 529020. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第1期85-92,共8页
This paper provides further contributions to the theory of linear sufficiency in the general Gauss-Markov model E(y)=Xβ,Var (y)=V.The notion of linear sufficiency introduced by Baksalary and Kala(1981) and Drygas(198... This paper provides further contributions to the theory of linear sufficiency in the general Gauss-Markov model E(y)=Xβ,Var (y)=V.The notion of linear sufficiency introduced by Baksalary and Kala(1981) and Drygas(1983) is extended for any specific estimable function c′β.Some general results with respect to the extended concept are obtained.An essential result concerning the former notion is a direct consequence of this paper. 展开更多
关键词 general linear model sufficiency BLUE linear sufficient statistics.
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ON SUFFICIENCY AND DUALITY OF SOLUTIONS FOR QUASI B_s-INVEX SEMI-INFINITE PROGRAMMING 被引量:1
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作者 张庆祥 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2001年第1期37-44,共8页
A class of functions called quasi B s invex and pseudo B s invex functions are introduced by using the concept of symmetric gradient. The examples of quasi B s invex and pseudo B s invex functions are given. The suffi... A class of functions called quasi B s invex and pseudo B s invex functions are introduced by using the concept of symmetric gradient. The examples of quasi B s invex and pseudo B s invex functions are given. The sufficient optimality conditions and Mond Weir type duality results are obtained for a nondifferentiable nonlinear semi infinite programming problem involving quasi B s invex and pseudo B s invex functions. 展开更多
关键词 INVEX quasi B s invex and pseudo B s invex sufficient optimality DUALITY semi infinite programming.
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Transcriptome Analysis and Physiological Responses of Economic Macroalga Gracilariopsis lemaneiformis under Sulfate Deficiency
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作者 Haojie Jia Hong Du +9 位作者 Muhmmad Aslam Tangcheng Li Canqi Zheng Xihui Xie Nan Huang Honghao Liang Pengbing Pei Ping Li Weizhou Chen Xiaojuan Liu 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第1期91-110,共20页
Sulfur is an essential macronutrient for the growth of all photosynthetic organisms and plays important roles in different metabolic pathways.However,sulfur metabolism and its related research on macroalgae with impor... Sulfur is an essential macronutrient for the growth of all photosynthetic organisms and plays important roles in different metabolic pathways.However,sulfur metabolism and its related research on macroalgae with important ecological value is rather limited.In this study,marine ecological valued macroalga Gracilariopsis lemaneiformis was used to study the general physiological responses and transcriptome profiling under the sulfate deficiency.The relative growth rate of algae under sulfate deficiency was statistically significantly lower than that of control after 6 days.However,no significant differences were observed in the pigments content and Fv/Fm value,indicating that the photosynthesis was not obviously affected under the sulfate deficiency.Furthermore,the significantly increased soluble protein and carbohydrate contents,and indistinctively differentially expressed sulfate transporter/permease(ST)and ATP sulfurylase(ATPS)genes suggesting that G.lemaneiformis cells did not use sulfur from internal protein and carbohydrate pools but utilize stored sulfur from vacuole to satisfy their nutritional requirements during the sulfate deficiency.Transcriptome data showed that most annotated differentially expressed genes(DEGs)were down-regulated under the sulfate deficiency,including a large proportion of genes involved in the pathway of sulfur metabolism.Therefore,it was concluded that the pathway of sulfur metabolism was suppressed under the sulfate deficiency in G.lemaneiformis.The results and analysis in this study provide a comprehensive understanding for the physiological and molecular response of G.lemaneiformis to sulfate deficiency. 展开更多
关键词 Gracilariopsis lemaneiformis sulfate deficiency sulfate sufficiency transcriptome
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When 2D Materials Encounter Disorder
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作者 刘磊 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第5期58-58,共1页
Back to the 1950s,Anderson revealed the absence of wave diffusion,i.e.,Anderson localization,in a sufficiently disordered media,marking the start of electron transport research in non-periodic lattices.[1]In a simplif... Back to the 1950s,Anderson revealed the absence of wave diffusion,i.e.,Anderson localization,in a sufficiently disordered media,marking the start of electron transport research in non-periodic lattices.[1]In a simplified theoretical model,one critical order parameter was proposed to determine the boundary of electron delocalization。 展开更多
关键词 simplified sufficiently ABSENCE
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SUFFICIENT AND NECESSARY CONDITIONS ON THE EXISTENCE AND ESTIMATES OF BOUNDARY BLOW-UP SOLUTIONS FOR SINGULAR p-LAPLACIAN EQUATIONS
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作者 张学梅 阚士坤 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1175-1194,共20页
Let?denote a smooth,bounded domain in R^(N)(N≥2).Suppose that g is a nondecreasing C^(1)positive function and assume that b(x)is continuous and nonnegative inΩ,and that it may be singular on■Ω.In this paper,we pro... Let?denote a smooth,bounded domain in R^(N)(N≥2).Suppose that g is a nondecreasing C^(1)positive function and assume that b(x)is continuous and nonnegative inΩ,and that it may be singular on■Ω.In this paper,we provide sufficient and necessary conditions on the existence of boundary blow-up solutions to the p-Laplacian problem△_(p)u=b(x)g(u)for x∈Ω,u(x)→+∞as dist(x,■Ω)→0.The estimates of such solutions are also investigated.Moreover,when b has strong singularity,the nonexistence of boundary blow-up(radial)solutions and infinitely many radial solutions are also considered. 展开更多
关键词 singular p-Laplacian equation boundary blow-up sub-supersolution method EXISTENCE nonexistence and estimates sufficient and necessary conditions
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Optimal vector-valued intensity measure for seismic collapse assessment of structures 被引量:5
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作者 Masood Yakhchalian Ahmad Nicknam Gholamreza Ghodrati Amiri 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2015年第1期37-54,共18页
The present study is aimed to investigate the ability of different intensity measures (IMs), including response spectral acceleration at the fundamental period of the structure, Sa(T1), as a common scalar IM and t... The present study is aimed to investigate the ability of different intensity measures (IMs), including response spectral acceleration at the fundamental period of the structure, Sa(T1), as a common scalar IM and twelve vector-valued IMs for seismic collapse assessment of structures. The vector-valued IMs consist of two components, with S(T1) as the first component and different parameters that are ratios of scalar IMs, as well as the spectral shape proxies εSa and N, as the second component. After investigating the properties of an optimal IM, a new vector-valued IM that includes the ratio of Sa(T1) to the displacement spectrum intensity (DSI) as the second component is proposed. The new IM is more efficient than other IMs for predicting the collapse capacity of structures. It is also sufficient with respect to magnitude, source-to-site distance, and scale factor for collapse capacity prediction of structures. To satisfy the predictability criterion, a ground motion prediction equation (GMPE) is determined for Sa(T1)/DSI by using the existing GMPEs. Furthermore, an empirical equation is proposed for obtaining the correlation between the components of the proposed IM. The results of this study show that using the new vector-valued IM leads to a more reliable seismic collapse assessment of structures. 展开更多
关键词 intensity measure efficiency sufficiency displacement spectrum intensity collapse capacity fragility surface
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A Note on Diophantine Equation Ax^4+ 1 = By^2 and Erdos’ Conjecture on Combinatorial Number
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作者 曹珍富 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第2期1-3,共3页
A necessary and suffcient condition is given for the equation Ax4+ 1 =By2 to have positive integer solution, and an effective method is derived for solving equation a2x4 + 1 = By2 in positive integers x, y for given h... A necessary and suffcient condition is given for the equation Ax4+ 1 =By2 to have positive integer solution, and an effective method is derived for solving equation a2x4 + 1 = By2 in positive integers x, y for given ho and B completely. Also, using a recently result of Ribet, Darmon and Merel, we proved that Erdos’ conjecture on combinatorial number is right. 展开更多
关键词 DIOPHANTINE equation necessary and SUFFICIENT condition Jacobi’s SYMBOL
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Efficiency and Duality in Nondifferentiable Multiobjective Programming Involving Directional Derivative
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作者 Izhar Ahmad 《Applied Mathematics》 2011年第4期452-460,共9页
In this paper, we introduce a new class of generalized dI-univexity in which each component of the objective and constraint functions is directionally differentiable in its own direction di for a nondifferentiable mul... In this paper, we introduce a new class of generalized dI-univexity in which each component of the objective and constraint functions is directionally differentiable in its own direction di for a nondifferentiable multiobjective programming problem. Based upon these generalized functions, sufficient optimality conditions are established for a feasible point to be efficient and properly efficient under the generalised dI-univexity requirements. Moreover, weak, strong and strict converse duality theorems are also derived for Mond-Weir type dual programs. 展开更多
关键词 MULTIOBJECTIVE PROGRAMMING NONDIFFERENTIABLE PROGRAMMING GENERALIZED dI-Univexity sufficiency DUALITY
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On the Choice of Reading Materials in TESL
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作者 CHE Ningwei 《Sino-US English Teaching》 2019年第10期415-418,共4页
The choice of reading materials partly decides the effectiveness of classroom reading instructions in TESL.This paper analyses the cognitive process of reading and some problems in classroom reading instructions of re... The choice of reading materials partly decides the effectiveness of classroom reading instructions in TESL.This paper analyses the cognitive process of reading and some problems in classroom reading instructions of reading course,and suggests three basic principles for choosing reading materials,including the principle of comprehensibility reading materials,readers’familiarity with the topics of the reading materials,and the sufficiency of reading materials. 展开更多
关键词 READING materials COMPREHENSIBILITY FAMILIARITY sufficiency
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Differential effect of biotin on carboxylase activity and mice skeletal muscle metabolism
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作者 Marco Antonio Parra Montes de Oca Gabriel Gutierrez-Ospina +4 位作者 Pablo Hofmann Salcedo Alma Lilia Fuentes-Farias Esperanza Melendez-Herrera Margarita Gomez-Chavarin Armida Baez-Saldana 《Advances in Bioscience and Biotechnology》 2013年第7期43-50,共8页
In mammalian skeletal muscle there are four carboxylases involved in several biochemical processes like gluconeogenesis, tricarboxylic acid cycle anaplerosis, metabolism of fatty acids and metabolism of various amino ... In mammalian skeletal muscle there are four carboxylases involved in several biochemical processes like gluconeogenesis, tricarboxylic acid cycle anaplerosis, metabolism of fatty acids and metabolism of various amino acids. It has been shown that biotin deficiency reduces body weight at the expense of muscular mass. When necessary, the liver uses skeletal muscle protein to provide glucose and amino acids to organs in need of such compounds. In this paper we analyzed carboxylase specific activities in hind limb skeletal muscle of 3 weeks old BALB/c male mice, at 0, 1, 4, 7, and 14 days of a specific diet with different biotin concentrations. Biotin was used at 0.0, 1.8 or 98.2 mg per kg of food;and was referred to as biotin deficient, sufficient and supplemented, respectively. Water and food supply and consumption by the three groups of mice were the same. Therefore, the observed effects were directly related to biotin ingestion. The body weight of biotin supplemented mice was the same as the body weight of mice in the biotin sufficient group, while biotin deficiency caused body weight reduction after 7 days of biotin depletion. We found that the total protein concentration in the vastus lateralis muscle is associated with the biotin content in the diet. After 7 days, the muscle total protein content was lower in mice of the biotin deficient group while it was higher in the mice from the biotin supplemented group 展开更多
关键词 Biotin Deficiency Biotin Supplementation Biotin sufficiency Skeletal Muscle Carboxylases Body Growth
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Mechanical model of water inrush from coal seam floor based on triaxial seepage experiments 被引量:35
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作者 Yihui Pang Guofa Wang Ziwei Ding 《International Journal of Coal Science & Technology》 EI CAS 2014年第4期428-433,共6页
In order to study the mechanism of confined water inrush from coal seam floor,the main influences on permeability in the process of triaxial seepage experiments were analyzed with methods such as laboratory experiment... In order to study the mechanism of confined water inrush from coal seam floor,the main influences on permeability in the process of triaxial seepage experiments were analyzed with methods such as laboratory experiments,theoretical analysis and mechanical model calculation.The crack extension rule and the ultimate destruction form of the rock specimens were obtained.The mechanism of water inrush was explained reasonably from mechanical point of view.The practical criterion of water inrush was put forward.The results show that the rock permeability "mutation" phenomenon reflects the differences of stress state and cracks extension rate when the rock internal crack begins to extend in large-scale.The rock ultimate destruction form is related to the rock lithology and the angle between crack and principal stress.The necessary condition of floor water inrush is that the mining pressure leads to the extension and transfixion of the crack.The sufficient condition of floor water inrush is that the confined water’s expansionary stress in normal direction and shear stress in tangential direction must be larger than the internal stress in the crack.With the two conditions satisfied at the same time,the floor water inrush accident will occur. 展开更多
关键词 Triaxial permeability experiment Floor water innush model Floor water inrush mechanism Necessary and sufficient conditions of water inrush
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Near optimal condition of OMP algorithm in recovering sparse signal from noisy measurement 被引量:5
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作者 Jia Li Qiang Wang Yi Shen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第4期547-553,共7页
This paper analyzes the performance of the orthogonal matching pursuit (OMP) algorithm in recovering sparse signals from noisy measurement. Considering the fact that some matrices satisfy some restricted isometry pr... This paper analyzes the performance of the orthogonal matching pursuit (OMP) algorithm in recovering sparse signals from noisy measurement. Considering the fact that some matrices satisfy some restricted isometry properties (RIPs) but not the coherence condition, a superior RIP-based condition is proposed, which means that if the measurement matrix satisfies δk+1 〈 1/(2 + √k) and the minimum component signal-to-noise ratio (MCSNR) is bounded, the OMP algorithm can exactly identify the support of the original sparse signal within k iterations. Finally, the theoretical results are verified by numerical simulations con- cerning different values of MCSNR and noise levels. 展开更多
关键词 compressive sensing (CS) orthogonal matching pur-suit (OMP) measurement matrix sufficient condition.
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SECOND-ORDER OPTIMALITY CONDITIONS FOR OPTIMAL CONTROL PROBLEMS GOVERNED BY 3-DIMENSIONAL NEVIER-STOKES EQUATIONS 被引量:5
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作者 王丽娟 何培杰 《Acta Mathematica Scientia》 SCIE CSCD 2006年第4期729-734,共6页
This article is concerned with second-order necessary and sufficient optimality conditions for optimal control problems governed by 3-dimensional Navier-Stokes equations. The periodic state constraint is considered.
关键词 Necessary and sufficient optimality conditions optimal control Navier-Stokes equation periodic state constraint
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ON THE BELTRAMI FLOWS 被引量:3
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作者 是长春 黄永念 陈耀松 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1992年第4期289-294,共6页
To illustrate the general properties of the Beltrami flows,a new sufficient and necessary condi- tion of the general solution of the Beltrami flows has been given,on whose basis some sufficient and necessary condition... To illustrate the general properties of the Beltrami flows,a new sufficient and necessary condi- tion of the general solution of the Beltrami flows has been given,on whose basis some sufficient and necessary conditions and sufficient conditions in literature are unified.The advantages of the new expressions are that one may get solutions of Beltrami flows with constant proportional factors which satisfy some given asymptotic decaying conditions at infinity.Finally,we find a class of spherical vortices of Beltrami flows,where the mo- tion trajectories of the fluid particles are confined within a sphere or two adjacent concentric spherical shells.We find that the superpositions of the spherical vortices of the same order with different polar axes may produce chaotic trajectories. 展开更多
关键词 Beltrami flow sufficient and necessary condition spherica vortex chaotic trajectory
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ON THE BOUNDEDNESS AND THE NORM OF A CLASS OF INTEGRAL OPERATORS 被引量:2
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作者 周立芳 《Acta Mathematica Scientia》 SCIE CSCD 2015年第6期1475-1482,共8页
The boundedness and the norm of a class of integral operators Ta,b,c on Lλ^P spaces are studied in this paper. The author not only gives the sufficient and necessary condition for the boundedness of Ta,b,c on Lλ^P,b... The boundedness and the norm of a class of integral operators Ta,b,c on Lλ^P spaces are studied in this paper. The author not only gives the sufficient and necessary condition for the boundedness of Ta,b,c on Lλ^P,but also obtains its accurate norm on Lλ^P for some range under the condition of c = n + a + b. 展开更多
关键词 integral operators sufficient condition necessary condition operator norm hypergeometric functions
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