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Classification of Relativity

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Journal of Modern Physics 2020年第4期11卷 535-564页

作者： Vu b. Ho Advanced Study 9 Adela Court Mulgrave Victoria Australia

In this work, we discuss the possibility to classify relativity in accordance with the classification of second order partial differential equations that have been applied into the formulation of physical laws in physics. In mathematics, since second order partial differential equations can be classified into hyperbolic, elliptic or parabolic type, therefore we show that it is also possible to classify relativity accordingly into hyperbolic, elliptic or parabolic type by establishing coordinate transformations that preserve the forms of these second order partial differential equations. The coordinate transformation that preserves the form of the hyperbolic equation is the Lorentz transformation and the associated space is the hyperbolic, or pseudo-Euclidean, relativistic spacetime. Typical equations in physics that comply with hyperbolic relativity are Maxwell and Dirac equations. The coordinate transformation that preserves the form of the elliptic equation is the modified Lorentz transformation that we have formulated in our work on Euclidean relativity and the associated space is the elliptic, or Euclidean, relativistic spacetime. As we will show in this work, equations that comply with elliptic relativity are the equations that describe the subfields of Maxwell and Dirac field. And the coordinate transformation that preserves the form of the parabolic equation is the Euclidean transformation consisting of the translation and rotation in the spatial space and the associated space is the parabolic relativistic spacetime, which is a Euclidean space with a universal time. Typical equations in physics that comply with parabolic relativity are the diffusion equation, the Schrödinger equation and in particular the diffusion equations that are derived from the four-current defined in terms of the differentiable structures of the spacetime manifold, and the Ricci flow.

关键词： Special Relativity Elliptic Equation Hyperbolic Equation Parabolic Equation Elliptic Relativity Hyperbolic Relativity Parabolic Relativity Classification of Relativity Maxwell and Dirac Field Maxwell and Dirac Subfield

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Journal of Energy Chemistry 2022年第10期31卷 88-113,I0003页

作者： Magno b.Costa Moisés A.de Araújo Marcos V.de Lima Tinoco Juliana F.de brito Lucia H.Mascaro Departamento de Química Universidade Federal de São CarlosRodovia Washington Luizkm 235São CarlosSão Paulo 13565-905Brazil Instituto de Química de São Carlos Universidade de São PauloAvenida Trabalhador Sancarlense400São CarlosSão Paulo 13566-590Brazil Instituto de Química Universidade Estadual PaulistaRua Professor Francisco Degnis/nAraraquaraSão Paulo 14800-900Brazil

This review shows the importance of WO_(3)photoanode as a potentially low-cost,efficient,stable,and photoactive material for light-driven water *** such,this manuscript aims to review the most recent publications regarding the strategies to improve the phoelectroactivity of WO_(3)films for water *** addition,this review aims to graphically highlight and discuss the general trendings of the photocurrent density response and stability test of the recent outstanding studies in the literature for photoelectrochemical water splitting *** strategies covered in this review will not only concern the WO_(3)morphology and crystal plane growth,but also the many arrangements possibilities to improve the WO_(3)efficiency for water photoelectrooxidation,such as defect engineering based on oxygen vacancies,doping,decorations,and homo and *** these strategies are compared by the photocurrent density results and by the stability of these *** best results in this sense were observed in cases where the use of heterojunction was applied together with a desired morphology and crystal plane of the WO_(3)***,the modifications that caused a decrease in the photocurrent density reaching values that are even lower than the pure WO_(3)were also *** this way,this review intends to improve the knowledge about the synthesis and design of WO_(3)photoanodes to further obtain an efficient photocatalyst to minimize the recombination losses or losses across the interfaces and improve the photoelectroactivity for water splitting in the large-scale application.

关键词： Solar energy H_(2)production N-type semiconductor Photoelectrode design Oxygen evolution reaction

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Mechanotransduction pathways in articular chondrocytes and the emerging role of estrogen receptor-α

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骨研究:英文版 2023年第2期11卷 229-247页

作者： Ning Wang Yangfan Lu benjamin b.Rothrauff Aojie Zheng Alexander Lamb Youzhen Yan Katelyn E.Lipa Guanghua Lei Hang Lin Department of Orthopaedic Surgery Xiangya HospitalCentral South UniversityChangsha 410008 HunanChina Department of Orthopaedic Surgery University of Pittsburgh School of MedicinePittsburghPA15219USA Department of bioengineering University of Pittsburgh Swanson School of EngineeringPittsburghPA15219USA and Mc Gowan Institute for Regenerative Medicine University of Pittsburgh School of MedicinePittsburghPA15219USA

In the synovial joint,mechanical force creates an important signal that influences chondrocyte *** conversion of mechanical signals into biochemical cues relies on different elements in mechanotransduction pathways and culminates in changes in chondrocyte phenotype and extracellular matrix composition/***,several mechanosensors,the first responders to mechanical force,have been ***,we still have limited knowledge about the downstream molecules that enact alterations in the gene expression profile during mechanotransduction ***,estrogen receptorα(ERα)has been shown to modulate the chondrocyte response to mechanical loading through a ligand-independent mechanism,in line with previous research showing that ERαexerts important mechanotransduction effects on other cell types,such as *** consideration of these recent discoveries,the goal of this review is to position ERαinto the mechanotransduction pathways known to ***,we first summarize our most recent understanding of the mechanotransduction pathways in chondrocytes on the basis of three categories of actors,namely mechanosensors,mechanotransducers,and ***,the specific roles played by ERαin mediating the chondrocyte response to mechanical loading are discussed,and the potential interactions of ERαwith other molecules in mechanotransduction pathways are ***,we propose several future research directions that may advance our understanding of the roles played by ERαin mediating biomechanical cues under physiological and pathological conditions.

关键词： structure loading directions

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Characterization of Generalized Uniform Distribution through Expectation

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Open Journal of Statistics 2014年第8期4卷 563-569页

作者： Milind b. bhatt Department of Statistics Sardar Patel University Vallabh Vidhyanagar India

Normally the mass of a root has a uniform distribution but some have different uniform distributions named Generalized Uniform Distribution (GUD). The characterization result based on expectation of function of random variable has been obtained for generalized uniform distribution. Applications are given for illustrative purpose including a special case of uniform distribution.

关键词： Characterization Generalized Uniform Distribution (GUD)

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bLADDER STONE

中华医学杂志(英文版) 1934年第5期048卷 462-474页

作者： PHILIP b.PRICE Department of Surgery Cheeloo University Medical School and Hospital Tsinan.

Vesical calculus is fairly common in Shantung *** is based on i26 cases admitted to the University Hospital duringthe last five *** of these patients were boys from the country,between five andfifteen years of age,who began to have symptoms in the spring of thesecond to sixth year of *** symptoms occur in attacksof increasing length and severity,until at length there are no symptom-less *** etiology of bladder stone is *** study of incidenceappears to lend some indirect support to the theory that dietary deficiency,perhaps Vitamine A deficiency,is an important causative *** our experience,x-ray examination is the most informative singlediagnostic procedure for bladder *** of the presence of stone in the bladder is not sufficient,*** condition of the urethra,bladder,kidneys,and body ingeneral should be *** severe cystitis or evidence of kidneydamage is found,operation is best delayed until the condition can *** treatment—pre-operative,operative,and Post-operative—deve-loped at the University Hospital is described in *** essentialfeatures are:adequate pre-operative treatment based upon careful andcomplcte diagnosis;suprapubic lithotomy,the bladder being distendedwith measured quantities of air;special care that the wound does not be- come contaminated by bladder contents;anatomical closure,withoutdrainage,of all the layers of the bladder wall;drainage of the bladderfor four or five days by means of a catheter carefully placed and securelyfastened in the urethra;attempts to restore the entire urinary tract *** partly impacted in the prostatic urethra present special *** are made for dealing with this sort of *** results of the different methods we have used in per-forming suprapubic lithotomy are *** results seem todemonstrate the superiority of the technique ***,we believe these

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Description of the Overland Route to China in Hudud al-‘Alam: Dates of the Underlying Itinerary

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欧亚学刊

欧亚学刊 2004年 179-197页

作者： Pavel b.Lurje Institut für Iranistik sterreichische Akademie d.Wissenschaften Institute of Oriental Studies St-Petersburg BranchRussian Academy of Sciences

SummaryThe present paper deals with the description of China and East Turkistan as presented in the anonymous Persian geographical treatise H·udūd al-‘lam("Regions of the World",composed in982 AD),and the paralle...

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THE SUPERFICIAL DEPOSITS OF YUTAOHO, SHANSI

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地质学报 1930年第4期 350-357页

作者： GEORGE b. bARbOUR Department of Geology Yenching University

An account is given of the structural relations of a curious Pleistocene conglomerate and a calcareous tufa in Yutaoho valley the interpretation of which bears on the problem of the Pleistocene history of Shansi. Obse... 详细信息

关键词： THE SUPERFICIAL DEPOSITS OF YUTAOHO SHANSI

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基于信道和队列状态信息的跨层最优功率分配

通信学报 2007年第8期28卷 16-23页

作者：陈巍曹志刚樊平毅 LETAIEF K b 清华大学电子工程系北京100084 香港科技大学电子与计算机工程系

研究基于完备信道和队列状态的最优功率分配策略。通过联合物理层和网络层的模型,建立了系统的跨层模型,进而在此基础上建立了功率分配的跨层优化问题。给出跨层最优功率分配问题的解析最优解和相应的算法,即"地窖注水"算法。说明传统的... 详细信息

研究基于完备信道和队列状态的最优功率分配策略。通过联合物理层和网络层的模型,建立了系统的跨层模型,进而在此基础上建立了功率分配的跨层优化问题。给出跨层最优功率分配问题的解析最优解和相应的算法,即"地窖注水"算法。说明传统的"注水策略"仅仅是所提出的地窖注水算法在不考虑队列长度下的一个特例。仿真将验证所提出策略相对于传统功率分配策略的性能优势。在同样的数据包到达率下,所提出的功率分配策略可以达到更小的排队时延。

关键词：无线网络网络信息论功率分配跨层

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Effects of the Fiber Diameter on Mechanic Properties in Polymethyl-Methacrylate Composites Reinforced with Goose Feather Fiber

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Materials Sciences and Applications 2017年第11期8卷 811-827页

作者： Kenan büyükkaya Gazipasa Campus Technical Sciences Vocational High School Giresun University Giresun Turkey

The polymethyl-methacrylate (PMMA)-based composites were prepared using goose feather fibers at different diameters. The fibers, which were washed and dried, cut through the shaft, and their sizes were shrunk to short fiber form. Then the obtained short fibers were added into acryl matrix in portions of 2%, 4%, 6%, and 8% in volume. The mixture containing goose feather fiber was shaped via free casting method, and the goose feather fiber/PMMA composites were obtained. The samples, which were processed in accordance with the standards of test to be implemented after the thermal curing process, were characterized in terms of the mechanical properties after being evaluated by using three-point flexure test and impact test. For the goose feather-added composites, a significant increase was observed in rupture resistance, flexural strength, and flexure module. The flexure test curves of composites clearly revealed the slow and stable crack enlargement. Micro mechanisms of toughening and rupture processes were observed under the light of microstructure of rupture surfaces. The results of present study showed that the goose feather can be used as an important reinforcing material for bio-composites.

关键词： Composite Mechanical Properties Goose Feather Fiber PMMA Fiber Diameter