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A Task-Oriented Hybrid Cloud Architecture with Deep Cognition Mechanism for Intelligent Space
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作者 Yongcheng Cui Guohui Tian Xiaochun Cheng 《Computers, Materials & Continua》 SCIE EI 2023年第8期1385-1408,共24页
Intelligent Space(IS)is widely regarded as a promising paradigm for improving quality of life through using service task processing.As the field matures,various state-of-the-art IS architectures have been proposed.Mos... Intelligent Space(IS)is widely regarded as a promising paradigm for improving quality of life through using service task processing.As the field matures,various state-of-the-art IS architectures have been proposed.Most of the IS architectures designed for service robots face the problems of fixedfunction modules and low scalability when performing service tasks.To this end,we propose a hybrid cloud service robot architecture based on a Service-Oriented Architecture(SOA).Specifically,we first use the distributed deployment of functional modules to solve the problem of high computing resource occupancy.Then,the Socket communication interface layer is designed to improve the calling efficiency of the function module.Next,the private cloud service knowledge base and the dataset for the home environment are used to improve the robustness and success rate of the robot when performing tasks.Finally,we design and deploy an interactive system based on Browser/Server(B/S)architecture,which aims to display the status of the robot in real-time as well as to expand and call the robot service.This system is integrated into the private cloud framework,which provides a feasible solution for improving the quality of life.Besides,it also fully reveals how to actively discover and provide the robot service mechanism of service tasks in the right way.The results of extensive experiments show that our cloud system provides sufficient prior knowledge that can assist the robot in completing service tasks.It is an efficient way to transmit data and reduce the computational burden on the robot.By using our cloud detection module,the robot system can save approximately 25% of the averageCPUusage and reduce the average detection time by 0.1 s compared to the locally deployed system,demonstrating the reliability and practicality of our proposed architecture. 展开更多
关键词 Service robot intelligent space cloud robot interactive robot system robot cloud service framework
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Research on the Campus Space Cognition and Active Path of Peking University Students
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作者 GONG Yuxuan 《Journal of Landscape Research》 2020年第4期9-13,共5页
Questionnaire survey and investigation were carried out to get students’feelings and cognition about campus of Peking University Shenzhen Graduate School,and active paths of their daily routine were analyzed to fi gu... Questionnaire survey and investigation were carried out to get students’feelings and cognition about campus of Peking University Shenzhen Graduate School,and active paths of their daily routine were analyzed to fi gure out the relationship between cognition and path.Characteristics of the students’space cognition and time-space active path were analyzed,and the causes of these characteristics explored to summarize the laws of students’daily life,and provide references to know psychologic status of students. 展开更多
关键词 Shenzhen Graduate School space cognition Daily routine Time-space path
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Space-Time Cognition Contrast between English and Chinese Reflected Through Plant Metaphor Translation
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作者 LIU Xiao BAO De-wang 《Journal of Literature and Art Studies》 2022年第12期1304-1313,共10页
This paper intends to demonstrate the differences in space-time cognition by contrasting the English translations of Chinese PLANT metaphors composed by English and Chinese translators.The materials used for analysis ... This paper intends to demonstrate the differences in space-time cognition by contrasting the English translations of Chinese PLANT metaphors composed by English and Chinese translators.The materials used for analysis are two English versions of the classic Chinese novel Dream of the Red Mansion translated by David Hawks and Yang Xianyi.The paper hypothesizes that Chinese is more space-oriented in plant conceptualization,while English is more time-oriented.We analyzed the cognitive reasons behind different translation strategies adopted for the same PLANT metaphor and verified the deduction from example analysis in the corpus.The typical PLANT metaphor analyzed in the research is the“root”metaphor.The results indicate that most Chinese“root”metaphors are“double-imaged”metonymic metaphors,which rely on the hierarchical correlation between plant components and the accumulation of spacial characteristics through multiple metonymies embedded in metaphorical projection.On the contrary,the conceptualization of“root”and“plant”in English pay more attention to the dynamic growth of the plant rather than the spacial relations between different parts. 展开更多
关键词 space-time cognition PLANT metaphor double-imaged metonymic metaphor
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Interpretation of Jadine's Identity Cognition inTar Babyfrom thePerspective of Space Theory
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作者 WANG Ruofan 《International English Education Research》 2019年第1期43-45,共3页
According to the contemporary Western theory of Lefebvre, the space is divided into three levels: physical space, spiritual space and social space. After going through the toss of the physical space, the exile of the ... According to the contemporary Western theory of Lefebvre, the space is divided into three levels: physical space, spiritual space and social space. After going through the toss of the physical space, the exile of the spiritual spaceas well as the dilemma of social space with the journey from Paris to Isle des Chevaliers, to New York, then to Eloe, and finally to Paris, Jadine in Tar Baby had broken the restriction of "dualism" andobtained the ethical identity and culture affiliation of ,"black&white", which will create a new path for the whole African-Americans to search for their ethnic identities and culture attributions. 展开更多
关键词 physical space SPIRITUAL space SOCIAL space IDENTITY exploration culture affiliation
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Impaired Cognition and Stroke Rehabilitation Outcomes: Are They Related?
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作者 Eric F. Tanlaka Torri Trojand 《Open Journal of Therapy and Rehabilitation》 2024年第2期101-116,共16页
Background: Stroke survivors who exhibit impaired cognition at admission to inpatient rehabilitation may experience participation challenges and poorer functional outcomes than those without impaired cognition. Differ... Background: Stroke survivors who exhibit impaired cognition at admission to inpatient rehabilitation may experience participation challenges and poorer functional outcomes than those without impaired cognition. Differences in functional outcomes between stroke survivors with and without impaired cognition may be attributed to age, level of cognitive impairment, and severity of stroke. Materials and Methods: A retrospective secondary data analysis was conducted using health-related administrative data acquired from a Southwestern Ontario hospital’s stroke rehabilitation database. The aim was to explore potential linkages between post-stroke impaired cognition and functional gains, rehabilitation stays, and living settings after discharge from rehabilitation. Results: An aggregate sample of 393 males and 314 females subclassified as experiencing mild, moderate, and severe stroke was analyzed. At inpatient rehabilitation admission, 21.5% (n = 152) of these patients had no impaired cognition, 33.7% (n = 238) had mild impaired cognition, 22.2% (n = 157) had moderate impaired cognition, and 22.6% (n = 160) had severe impaired cognition. Cognitively impaired stroke patients were significantly (p 0.001) older, had (mostly) moderate to severe stroke with significantly (p = 0.012) more moderate cognitive impairment, had significantly (p 0.001) longer rehabilitation stays, and a high propensity for being discharged to longer-term care facilities compared to non-cognitively impaired patients. Conclusion: Presence of significant dissimilarity in rehabilitation stays and post-discharge destinations among stroke survivors with and without cognitive impairment is attributed to the age of the patient, level of cognitive impairment, and rigorous rehabilitation interventions. 展开更多
关键词 STROKE Impaired cognition Inpatient Rehabilitation Functional Outcomes
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Exploration and Practice of Life Education Curriculum Based on Embodied Cognition Theory
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作者 Jing Zhang 《Journal of Contemporary Educational Research》 2024年第5期270-275,共6页
In recent years,the suicide rate of adolescents has been increasing year by year,and life and health problems have become the most important in education.It is urgent to promote the construction of the curriculum of l... In recent years,the suicide rate of adolescents has been increasing year by year,and life and health problems have become the most important in education.It is urgent to promote the construction of the curriculum of life education effectively.In view of the“vacuity”and“fragmented”state of traditional life education,this paper combs the teaching objectives,teaching contents,teaching methods,and teaching evaluation of life education from the perspective of embodied cognition theory,to explore the construction of positive experience of life education curriculum. 展开更多
关键词 Embodied cognition EXPERIENTIAL Life education
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Research on Children’s Game Activity Design Strategies Based on Embodied Cognition Theory
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作者 Xiangmiao He 《Journal of Contemporary Educational Research》 2024年第4期54-58,共5页
Edutainment,in the kindergarten education stage,emphasizes the game as the basic activity and combines the content of education with the form of the game,thus it also forms the educational method of gamification teach... Edutainment,in the kindergarten education stage,emphasizes the game as the basic activity and combines the content of education with the form of the game,thus it also forms the educational method of gamification teaching.Through investigation and analysis,it is found that the current kindergarten game activity design has the problem of improper combination of educational content and game form.The current kindergarten game activity design has problems such as stereotypes,children’s lack of active learning opportunities in activities,teachers’insufficient theoretical understanding,inappropriate teacher guidance methods,and so on.Embodied cognition theory attaches importance to the important role of the body in the development of cognition,provides new guidance for classroom teaching,and opens up a new path for classroom teaching reform.Based on the perspective of embodied cognition theory,the concept of body and mind integration should be adhered to in kindergarten teaching with games as the basic activity,experiential teaching situation should be created,children’s subjective experience should be respected,and games and interactions should be designed to promote children’s physical and mental participation,thus laying a foundation for the realization of children’s individual freedom,autonomy,and all-round development.Therefore,this paper aims at the existing problems in the current kindergarten gamification teaching and discusses the design strategy of children’s game activities based on embodied cognition theory. 展开更多
关键词 Embodied cognition Children’s play Game activity design
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Impact of propofol and sevoflurane anesthesia on cognition and emotion in gastric cancer patients undergoing radical resection
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作者 Ao-Han Li Su Bu +2 位作者 Ling Wang Ai-Min Liang Hui-Yu Luo 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第1期79-89,共11页
BACKGROUND Propofol and sevoflurane are commonly used anesthetic agents for maintenance anesthesia during radical resection of gastric cancer.However,there is a debate concerning their differential effects on cognitiv... BACKGROUND Propofol and sevoflurane are commonly used anesthetic agents for maintenance anesthesia during radical resection of gastric cancer.However,there is a debate concerning their differential effects on cognitive function,anxiety,and depression in patients undergoing this procedure.AIM To compare the effects of propofol and sevoflurane anesthesia on postoperative cognitive function,anxiety,depression,and organ function in patients undergoing radical resection of gastric cancer.METHODS A total of 80 patients were involved in this research.The subjects were divided into two groups:Propofol group and sevoflurane group.The evaluation scale for cognitive function was the Loewenstein occupational therapy cognitive assessment(LOTCA),and anxiety and depression were assessed with the aid of the self-rating anxiety scale(SAS)and self-rating depression scale(SDS).Hemodynamic indicators,oxidative stress levels,and pulmonary function were also measured.RESULTS The LOTCA score at 1 d after surgery was significantly lower in the propofol group than in the sevoflurane group.Additionally,the SAS and SDS scores of the sevoflurane group were significantly lower than those of the propofol group.The sevoflurane group showed greater stability in heart rate as well as the mean arterial pressure compared to the propofol group.Moreover,the sevoflurane group displayed better pulmonary function and less lung injury than the propofol group.CONCLUSION Both propofol and sevoflurane could be utilized as maintenance anesthesia during radical resection of gastric cancer.Propofol anesthesia has a minimal effect on patients'pulmonary function,consequently enhancing their postoperative recovery.Sevoflurane anesthesia causes less impairment on patients'cognitive function and mitigates negative emotions,leading to an improved postoperative mental state.Therefore,the selection of anesthetic agents should be based on the individual patient's specific circumstances. 展开更多
关键词 PROPOFOL SEVOFLURANE Radical resection of gastric cancer Anesthetic effect cognitive function Negative emotion
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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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3D MERGE与3D SPACE STIR序列在腰椎间盘突出症检查中的应用比较 被引量:1
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作者 李兰 殷小丹 +2 位作者 李旭雪 吴海燕 张滔 《中国医学物理学杂志》 CSCD 2024年第1期27-31,共5页
目的:对比三维多回波恢复梯度回波(3D MERGE)、三维可变反转角快速自旋回波(3D SPACE STIR)序列在腰椎间盘突出症(LDH)检查中的应用效果。方法:选择2020年1月~2022年11月收治的135例LDH患者,回顾性分析患者临床和磁共振成像(MRI)资料,... 目的:对比三维多回波恢复梯度回波(3D MERGE)、三维可变反转角快速自旋回波(3D SPACE STIR)序列在腰椎间盘突出症(LDH)检查中的应用效果。方法:选择2020年1月~2022年11月收治的135例LDH患者,回顾性分析患者临床和磁共振成像(MRI)资料,所有患者均接受常规MRI扫描及3D MERGE、3D SPACE STIR序列扫描,对比3D MERGE、3D SPACE STIR序列测量神经根直径的一致性,评价两种序列的图像质量参数[信噪比(SNR)、对比噪声比(CNR)]、图像清晰度评分。结果:3D MERGE和3D SPACE STIR序列测量的L3~S1神经根直径比较差异无统计学意义(P>0.05),且两组序列测量的L3、L4、L5和S1直径均显示出较高相关性(r=0.957,0.986,0.975,0.972,P<0.05);3D MERGE序列的SNR及CNR均高于3D SPACE STIR序列,神经根显示分级、图像清晰度评分优于3D SPACE STIR序列,差异有统计学意义(P<0.05)。结论:3D MERGE、3D SPACE STIR序列在LDH神经根直径测量中具有极高一致性,3D MERGE序列较3D SPACE STIR序列能够更清晰显示神经跟的解剖形态,图像质量更好。 展开更多
关键词 腰椎间盘突出症 3D MERGE 3D space STIR 神经根直径 图像质量
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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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3D printing in space:from mechanical structures to living tissues
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作者 Mao Mao Zijie Meng +6 位作者 Xinxin Huang Hui Zhu Lei Wang Xiaoyong Tian Jiankang He Dichen Li Bingheng Lu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期378-387,共10页
3D printing stands at the forefront of transforming space exploration,offering unprecedented on-demand and rapid manufacturing capabilities.It adeptly addresses challenges such as mass reduction,intricate component fa... 3D printing stands at the forefront of transforming space exploration,offering unprecedented on-demand and rapid manufacturing capabilities.It adeptly addresses challenges such as mass reduction,intricate component fabrication,and resource constraints.Despite the obstacles posed by microgravity and extreme environments,continual advancements underscore the pivotal role of 3D printing in aerospace science.Beyond its primary function of producing space structures,3D printing contributes significantly to progress in electronics,biomedicine,and resource optimization.This perspective delves into the technological advantages,environmental challenges,development status,and opportunities of 3D printing in space.Envisioning its crucial impact,we anticipate that 3D printing will unlock innovative solutions,reshape manufacturing practices,and foster self-sufficiency in future space endeavors. 展开更多
关键词 3D printing in space space manufacturing MICROGRAVITY
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Metallurgical performance evaluation of space-weathered Chang’e-5 lunar soil
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作者 Chen Li Wenhui Ma +1 位作者 Yang Li Kuixian Wei 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1241-1248,共8页
Space metallurgy is an interdisciplinary field that combines planetary space science and metallurgical engineering.It involves systematic and theoretical engineering technology for utilizing planetary resources in sit... Space metallurgy is an interdisciplinary field that combines planetary space science and metallurgical engineering.It involves systematic and theoretical engineering technology for utilizing planetary resources in situ.However,space metallurgy on the Moon is challenging because the lunar surface has experienced space weathering due to the lack of atmosphere and magnetic field,making the mi-crostructure of lunar soil differ from that of minerals on the Earth.In this study,scanning electron microscopy and transmission electron microscopy analyses were performed on Chang’e-5 powder lunar soil samples.The microstructural characteristics of the lunar soil may drastically change its metallurgical performance.The main special structure of lunar soil minerals include the nanophase iron formed by the impact of micrometeorites,the amorphous layer caused by solar wind injection,and radiation tracks modified by high-energy particle rays inside mineral crystals.The nanophase iron presents a wide distribution,which may have a great impact on the electromagnetic prop-erties of lunar soil.Hydrogen ions injected by solar wind may promote the hydrogen reduction process.The widely distributed amorph-ous layer and impact glass can promote the melting and diffusion process of lunar soil.Therefore,although high-energy events on the lun-ar surface transform the lunar soil,they also increase the chemical activity of the lunar soil.This is a property that earth samples and tradi-tional simulated lunar soil lack.The application of space metallurgy requires comprehensive consideration of the unique physical and chemical properties of lunar soil. 展开更多
关键词 space metallurgy Chang’e-5 lunar soil space weathering metallurgical performance
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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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From“Car Priority”to“People Priority”: Exploring New Ideas for Refined Road Space Design
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作者 HUANG Xin 《Journal of Landscape Research》 2024年第2期25-29,共5页
Roads are crucial public spaces in cities and serve as a window to showcase the city’s characteristics.They serve not only as a means of urban transportation but also as a crucial spatial carrier for urban communicat... Roads are crucial public spaces in cities and serve as a window to showcase the city’s characteristics.They serve not only as a means of urban transportation but also as a crucial spatial carrier for urban communication activities and a significant location for meeting the increasing demands of people for a better quality of life.The current road infrastructure prioritizes the right of way for cars,neglecting the design of sidewalks and green belts within the road’s boundaries,and extension spaces between buildings and boundary lines of roads.There is a pressing need to improve street space in response to the demand for development transformation and the creation of a warmer city.This paper summarizes common problems in current road spaces,draws on the experience of excellent urban road spaces in foreign countries,discusses new ideas for the refined design of road spaces based on the transformation of road planning concepts,and suggests a reference standard for guiding detailed design.Simultaneously,the review of road construction will incorporate the detailed design of road space to enhance the role of planning in guiding and controlling the construction of road works. 展开更多
关键词 Road space Refined design Communication space City perception
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Space Topologies and Their Dual Space Topologies for Conventional Functional Space Topologies
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作者 Mahjoub A. Elamin 《Journal of Applied Mathematics and Physics》 2024年第3期778-804,共27页
In this paper, we have studied the topology of some classical functional spaces. Among these spaces, there are standard spaces, spaces that can be metrizable and others that cannot be metrizable. But they are all topo... In this paper, we have studied the topology of some classical functional spaces. Among these spaces, there are standard spaces, spaces that can be metrizable and others that cannot be metrizable. But they are all topological vector spaces and it is in this context that we have chosen to present this work. We are interested in the topology of its spaces and in the topologies of their dual spaces. The first part, we presented the fundamental topological properties of topological vector spaces. The second part, we studied Frechet spaces and particularly the space S(R<sup>n</sup>) of functions of class C<sup>∞ </sup>on R<sup>n</sup> which are as well as all their rapidly decreasing partial derivatives. We have also studied its dual S'(Rn</sup>) the space of tempered distributions. The last part aims to define a topological structure on an increasing union of Frechet spaces called inductive limit of Frechet spaces. We study in particular the space D(Ω) of functions of class C<sup>∞</sup> with compact supports on Ω as well as its dual D' (Ω) the space distributions over the open set Ω. 展开更多
关键词 Linear Forms Dual spaces Frechet spaces Partial Derivatives DISTRIBUTIONS Topological Structure Weak Topology Strong Topology
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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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Space/Air Covert Communications:Potentials,Scenarios,and Key Technologies
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作者 Mao Haobin Liu Yanming +5 位作者 Zhu Lipeng Mao Tianqi Xiao Zhenyu Zhang Rui Han Zhu Xia Xianggen 《China Communications》 SCIE CSCD 2024年第3期1-18,共18页
Space/air communications have been envisioned as an essential part of the next-generation mobile communication networks for providing highquality global connectivity. However, the inherent broadcasting nature of wirel... Space/air communications have been envisioned as an essential part of the next-generation mobile communication networks for providing highquality global connectivity. However, the inherent broadcasting nature of wireless propagation environment and the broad coverage pose severe threats to the protection of private data. Emerging covert communications provides a promising solution to achieve robust communication security. Aiming at facilitating the practical implementation of covert communications in space/air networks, we present a tutorial overview of its potentials, scenarios, and key technologies. Specifically, first, the commonly used covertness constraint model, covert performance metrics, and potential application scenarios are briefly introduced. Then, several efficient methods that introduce uncertainty into the covert system are thoroughly summarized, followed by several critical enabling technologies, including joint resource allocation and deployment/trajectory design, multi-antenna and beamforming techniques, reconfigurable intelligent surface(RIS), and artificial intelligence algorithms. Finally, we highlight some open issues for future investigation. 展开更多
关键词 artificial intelligence(AI) sixth generation(6G) space-air-ground integrated networks(SAGINs) space/air covert communications
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Modified Lorentz Transformations and Space-Time Splitting According to the Inverse Relativity Model
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作者 Michael Girgis 《Journal of Applied Mathematics and Physics》 2024年第7期2467-2489,共23页
Analysis of a four-dimensional displacement vector on the fabric of space-time in the special or general case into two Four-dimensional vectors, according to specific conditions leads to the splitting of the total fab... Analysis of a four-dimensional displacement vector on the fabric of space-time in the special or general case into two Four-dimensional vectors, according to specific conditions leads to the splitting of the total fabric of space-time into a positive subspace-time that represents the space of causality and a negative subspace-time which represents a space without causality, thus, in the special case, we have new transformations for the coordinates of space and time modified from Lorentz transformations specific to each subspace, where the contraction of length disappears and the speed of light is no longer a universal constant. In the general case, we have new types of matric tensor, one for positive subspace-time and the other for negative subspace-time. We also find that the speed of the photon decreases in positive subspace-time until it reaches zero and increases in negative subspace-time until it reaches the speed of light when the photon reaches the Schwarzschild radius. 展开更多
关键词 Four-Dimensional Vector Analysis Four-Dimensional Subspace Causal space Analysis of the Speed of Light Inverse Theory of Relativity
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