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Time to recovery from severe pneumonia and its predictors among pediatric patients admitted in Mizan-Tepi University Teaching Hospital,South West Ethiopia,2022
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作者 Belete Fenta Kebede Aynalem Yetwale Hiwot +2 位作者 Tsegaw Biyazin Tesfa Yalemtsehay Dagnaw Genie Nigatu Dessalegn Mulu 《Frontiers of Nursing》 2024年第3期343-353,共11页
Objective:Despite trials and programs for the prevention of childhood mortality due to pneumonia,Ethiopia is among the top five countries with the highest number of deaths due to pneumonia.Although the prevalence of p... Objective:Despite trials and programs for the prevention of childhood mortality due to pneumonia,Ethiopia is among the top five countries with the highest number of deaths due to pneumonia.Although the prevalence of pneumonia has increased in the abovementioned trials,little is known about the recovery time from severe pneumonia and its predictors in the study area.Therefore,this study aimed to assess the time to recovery from severe pneumonia and its predictors among pediatric patients admitted to Mizan-Tepi University Teaching Hospital,Ethiopia,in 2022.Methods:A total of 591 children admitted for severe pneumonia were selected using simple random sampling.Data were entered into Epi-data version 4.4.2.1 and expor ted to STATA version 14 for analysis,and the assumptions of Cox propor tional hazard models and goodness of fit were assessed through Shoenfeld residual and Cox-Snell residual,respectively.Bivariate and multivariable Cox regression models were used to identify the predictors of mor tality.Results:This study revealed that 91.54%(95%confidence interval[CI]:89.00–93.53)of participants recovered with an incidence rate of 24.10(95%CI:22.15–26.21)per 100 person-day–observations.The hmedian recovery time of children was 4 days(95%CI:2–6).Children who were not exclusively breastfed(AHR=1.3;95%CI:1.03–1.66),who had a history of inability to suck/feed(AHR=0.81;95%CI:0.65–0.99)were independent predictors of the time to recovery.Conclusions:Children with severe pneumonia who had not exclusively breastfed and who had a history of inability to suck/feed were independent predictors of time to recovery.Therefore,all stakeholders and concerned health care providers should focus more on early diagnosis and management and hasten early recovery based on the identified factors. 展开更多
关键词 Mizan-Tepi university Teaching Hospital pediatric patients PREDICTORS severe pneumonia Southwest Ethiopia time to recovery
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The Jiao Tong University Spectroscopic Telescope Project 被引量:1
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作者 JUST Team Chengze Liu +28 位作者 Ying Zu Fabo Feng Zhaoyu Li Yu Yu Hua Bai Xiangqun Cui Bozhong Gu Yizhou Gu Jiaxin Han Yonghui Hou Zhongwen Hu Hangxin Ji Yipeng Jing Wei Li Zhaoxiang Qi Xianyu Tan Cairang Tian Dehua Yang Xiangyan Yuan Chao Zhai Congcong Zhang Jun Zhang Haotong Zhang Pengjie Zhang Yong Zhang Yi Zhao Xianzhong Zheng Qingfeng Zhu Xiaohu Yang 《Astronomical Techniques and Instruments》 CSCD 2024年第1期16-30,共15页
The Jiao Tong University Spectroscopic Telescope(JUST)is a 4.4-meter f/6.0 segmented-mirror telescope dedicated to spectroscopic observations.The JUST primary mirror is composed of 18 hexagonal segments,each with a di... The Jiao Tong University Spectroscopic Telescope(JUST)is a 4.4-meter f/6.0 segmented-mirror telescope dedicated to spectroscopic observations.The JUST primary mirror is composed of 18 hexagonal segments,each with a diameter of 1.1 m.JUST provides two Nasmyth platforms for placing science instruments.One Nasmyth focus fits a field of view of 10′and the other has an extended field of view of 1.2°with correction optics.A tertiary mirror is used to switch between the two Nasmyth foci.JUST will be installed at a site at Lenghu in Qinghai Province,China,and will conduct spectroscopic observations with three types of instruments to explore the dark universe,trace the dynamic universe,and search for exoplanets:(1)a multi-fiber(2000 fibers)medium-resolution spectrometer(R=4000-5000)to spectroscopically map galaxies and large-scale structure;(2)an integral field unit(IFU)array of 500 optical fibers and/or a long-slit spectrograph dedicated to fast follow-ups of transient sources for multi-messenger astronomy;(3)a high-resolution spectrometer(R~100000)designed to identify Jupiter analogs and Earth-like planets,with the capability to characterize the atmospheres of hot exoplanets. 展开更多
关键词 Astronomical instrumentation Optical telescopes Large-scale structure of the universe Redshift surveys time domain astronomy Exoplanet astronomy
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Nighttime meridional neutral wind responses to SAPS simulated by the TIEGCM:A universal time effect 被引量:2
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作者 KeDeng Zhang Hui Wang +3 位作者 WenBin Wang Jing Liu ShunRong Zhang Cheng Sheng 《Earth and Planetary Physics》 CSCD 2021年第1期52-62,共11页
The present work uses the Thermosphere Ionosphere Electrodynamics General Circulation Model(TIEGCM),under geomagnetically disturbed conditions that are closely related to the southward interplanetary magnetic field(IM... The present work uses the Thermosphere Ionosphere Electrodynamics General Circulation Model(TIEGCM),under geomagnetically disturbed conditions that are closely related to the southward interplanetary magnetic field(IMF),to investigate how the nighttime poleward wind(30°–50°magnetic latitude and 19–22 magnetic local time)responds to subauroral polarization streams(SAPS)that commence at different universal times(UTs).The SAPS effects on the poleward winds show a remarkable UT variation,with weaker magnitudes at 00 and 12 UT than at 06 and 18 UT.The strongest poleward wind emerges when SAPS commence at 06 UT,and the weakest poleward wind develops when SAPS occur at 00 UT.A diagnostic analysis of model results shows that the pressure gradient is more prominent for the developing of the poleward wind at 00 and 12 UT.Meanwhile,the effect of ion drag is important in the modulation of the poleward wind velocity at 06 and 18 UT.This is caused by the misalignment of the geomagnetic and geographic coordinate systems,resulting in a large component of ion drag in the geographically northward(southward)direction due to channel orientation of the SAPS at 06 and 18 UT(00 and 12 UT).The Coriolis force effect induced by westward winds maximizes(minimizes)when SAPS commence at 12 UT(00 UT).The centrifugal force due to the accelerated westward winds shows similar UT variations as the Coriolis force,but with an opposite effect. 展开更多
关键词 Subauroral Polarization Streams TIEGCM poleward winds universal time change
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On Universal Space and Time
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作者 Caesar P. Viazminsky Piere K. Vizminiska 《Applied Mathematics》 2014年第16期2530-2546,共17页
In earlier papers [1]-[4], it was shown that the consistency of the concept of time with motion requires time and distance to be of the same dimension, and thus measured by the same unit. The arising reduced system of... In earlier papers [1]-[4], it was shown that the consistency of the concept of time with motion requires time and distance to be of the same dimension, and thus measured by the same unit. The arising reduced system of units revealed that mass and energy were only different facets of one entity, and resulted in the well-known mass-energy equivalence formula as a natural consequence. The physical space can be identified with any inertial frame, but when it comes to comparing the results of measurements in two frames, or more, only one frame, say S, can be taken stationary and identified with the physical space, whereas all other inertial frames are moving relative to S. The equivalence of inertial frames as sites of one physical world implies that an intrinsic units system of length, time, mass and charge should be defined in terms of basic constituent physical blocks that have the same identity in all inertial frames. A basic feature of the universal space and time theory (UST) is that the same one time prevails in all inertial frames. The scaling transformations (STs) that relate the geometric distances in two frames, S (s) when chosen the stationary frame, are derived, and applied to explain the Doppler’s effect. The time distance between a moving object in S and an observer depends on its state of motion;and the Euclidean form of the STs is employed to explain arrival of some meta-stable at the earth’s surface despite its short lifetime. The quantitative predicted Doppler’s effect, which is in a striking agreement with the Ives-Stilwell experimental results, coincides with the relativistic prediction for longitudinal motion, but yet predicts a complete absence of a transverse effect at a right angle. In coming parts of this work it will be shown that the UST explains elaborately the drag effect, stellar aberration, and produces naturally the relativistic mechanics. The UST will also be completed through deriving the scaling transformations of the second type, by which the null results of Michelson and Morley experiment, Michelson and Gale experiment, and the Sagnac effect are explained. The current work and our intended future works in UST are new versions containing basic conceptions and visions that didn’t appear in earlier versions [1]-[6]. 展开更多
关键词 Reduced System of UNITS INTRINSIC UNITS universal time and DISTANCE Mass-Energy EQUIVALENCE
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The Whole Theory of This Universe—A Step Forward to Einstein. Part-4: “Concept Map of Rotating Universe”
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作者 Rehana Kousar 《Journal of Applied Mathematics and Physics》 2024年第5期1699-1724,共26页
The article collectively proposes a revolutionary perspective on the universe, intertwining concepts of time, spatial positioning, and cosmic dynamics. We introduce the idea of a rotating universe centered around Mega... The article collectively proposes a revolutionary perspective on the universe, intertwining concepts of time, spatial positioning, and cosmic dynamics. We introduce the idea of a rotating universe centered around Mega Central Energy Pools (MCEPs), where time varies relative to the distance from the universe’s center, potentially enabling time travel. This model challenges conventional notions of time and cosmology, suggesting that black holes and white holes act as cosmic recycling factories. Additionally, this model unveils a novel theory of dark matter, positing photons as its constituents and highlighting their role in energy transfer across the cosmos. Furthermore, the investigation into Venus’s unique day-length-to-year-length ratio unveils a microscopic mechanism involving swirling energy droplets, charged particles, and field interactions, offering insights into planetary dynamics on both micro and macro scales. 展开更多
关键词 Rotating universe time Stair time Acceleration time Dilations Accelerating Galaxies
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Paper Analysis of Shanghai Ocean University in Bibliometric Method from Web of Science
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作者 Jia Jiang 《Journal of Applied Mathematics and Physics》 2024年第2期632-638,共7页
The data of this research was mainly collected from the Web of Science (WOS) and Incites database platform, which was filtered and cataloged according to the different platforms. For tracing the change in scientific r... The data of this research was mainly collected from the Web of Science (WOS) and Incites database platform, which was filtered and cataloged according to the different platforms. For tracing the change in scientific research at Shanghai Ocean University, make use of Bibliometric analysis to get the image and table of highly cited papers and hot papers. In this study, the scientific aspects in highly cited papers and hot papers, published in the last year in the core collection of Web of Science, were taken as objects, and office software was used as the main tool to carry out bibliometric and figure analysis. From the four aspects to find the difference in these fields, the production of specific fields and cited times is inconsistent. And suggest the department and management adjust the policy and method via elastic personnel and rewards to prompt the advancement of the research fields. 展开更多
关键词 Highly Cited Papers Hot Paper Shanghai Ocean university COMPARISON Cited times AUTHOR
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“Eternal Motion” as a “Form of Movement of a Special Nature” and the Main Condition for the Creation of the Universe
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作者 Avas Khugaev Eugeniya Bibaeva 《Journal of Applied Mathematics and Physics》 2024年第6期2041-2068,共28页
The article hypothesizes that DE and DM (UCM) are a “Form of Motion of a Special Nature”, where “Form of Motion” means “Eternal Motion” as the power of dynamics of different levels and varying degrees of self-su... The article hypothesizes that DE and DM (UCM) are a “Form of Motion of a Special Nature”, where “Form of Motion” means “Eternal Motion” as the power of dynamics of different levels and varying degrees of self-sufficiency, and by “Special Nature”, gravitational and two other properties of matter, “tied” to the “Eternal Movement” and completely dependent on it. Carriers of key properties of a “Special Nature” have been established: “0”-DE particles and “3”-DM particles (UDM). The unity of their inherent “motionally-gravitational” properties and the peculiarity of the relationship between “motion” and “gravity” are revealed: the higher the intensity of “Eternal Motion”, the stronger the gravitational properties of matter are manifested (and vice versa). The relationship of “time” with the “vibration frequency” and the “mass” of photons with the “degree of bonding and deformation properties of the field” is shown. The maximum level of gravity has been determined, which allows Nature to successfully create the Universe: such a landmark is the proximity to the property of the Primary Source—the “pure graviton” of the OSP space, the most powerful “motionally-gravitational” particle of the Universe. The reasons for the emergence of such an identity of the gravitational properties of particles with the indicators of a “pure graviton” are established: for “0”-DE particles, this is the acquisition of the function of “freedom of movement”;for “3”-DM particles (UDM), the creation of a special structure—a “double field” (“Main” and “Small”). The presence in the “double field” of specific “tools” for the creation of the worlds of the Universe—gravitational “waves” gives rise to impulses (shocks) of varying intensity and shape. A list of functions performed by “waves” in the “Main” and “Small” fields has been compiled. The specific conditions for the formation of “UDM Streams”, their transformation into a “Vortex” and, under the influence of a powerful Initial Impulse (push), sending them to the “place” of the creation of galaxies, are shown. It is suggested that there is a “Cycle of Matter in Nature” in the closed structure of our Universe due to the “work” of “waves” and the functioning of special “factories” in the form of exotic space objects—Black holes. 展开更多
关键词 DE DM (UCM) Graviton Eternal motion Double Field of the universe Motionally-Gravitational Particles Degree of Self-Sufficiency Main Field Small Field Gravitational Waves Primary Impulse Flows UDM Vortex time Massive Photons Clumps of DM Movement of Galaxies Factories of Black Holes Circulation of Matter in Nature
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Laser, Universe and Arrow of Time
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作者 Mitali Konwar Gauranga Dhar Baruah 《Optics and Photonics Journal》 2019年第8期127-139,共13页
We have presented a comparison between the universe and the Laser. In many ways, the physics of laser and the universe are analogous. The root of the analogy is the fact that both laser and early universe depend compl... We have presented a comparison between the universe and the Laser. In many ways, the physics of laser and the universe are analogous. The root of the analogy is the fact that both laser and early universe depend completely on the quantum nature. We have also presented a simple analogous example of the growth of a flower at successive stages of development and shown how the arrow of time may be represented in these cases. 展开更多
关键词 LASER universE time
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The Relativity of Cosmic Time: The Universe Is a Black Hole
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作者 Pascal Churoux 《Journal of Modern Physics》 2015年第13期1840-1851,共12页
Up to now, cosmology metrics have been based on Einstein relativity, established in 1905. Hubble has discovered the correlation between redshift and distance. Cosmology interprets the redshift as an expansion effect a... Up to now, cosmology metrics have been based on Einstein relativity, established in 1905. Hubble has discovered the correlation between redshift and distance. Cosmology interprets the redshift as an expansion effect a(t) through the ΛCDM model. We have proposed a new theory to explain Hubble law. The theory has been validated against observation data. It proposes a new approach of time which introduces the cosmic time tc. Cosmic time is an absolute reference to universe. It is zero at the edge with tc = 0, tc = T at the observer position and tc = s for any source between the edge and the observer, with T > s > 0. This theory acts like the relativity of space-time. The redshift is interpreted as a perspective parameter p(tc) = tc/T. Using gravitation, it is the Einstein effect applied to the uni-verse. This paper comments and interprets further consequences of this new theory. We emphasize the difference between duration (as usually used in classical cosmologic metrics) and the cosmic time tc as a notion of date. It induces two related effects: relativity of speed of light and time stretching. We explain why the cosmological standard model is not well suited to describe the Hubble law, to describe the universe. We also explain why gravitation and temperature increase when going from the center to the edge of the universe, when going from present to birth. The model has no use of black energy. As a consequence, the universe is seen as a black hole created by the cosmic time shock wave when tc = 0. 展开更多
关键词 HUBBLE Law Space-time RELATIVITY Light Speed universE Expansion REDSHIFT Big Bang Black Hole COSMIC time
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The Explanation of the Michelson-Morley Experiment Results by Means Universal Frame of Reference
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作者 Karol Szostek Roman Szostek 《Journal of Modern Physics》 2017年第11期1868-1883,共16页
It is commonly thought that the Michelson-Morley experiment from 1887 and Kennedy-Thorndike experiment from 1932 demonstrated that the universal frame of reference (ether) does not exist and that the velocity of light... It is commonly thought that the Michelson-Morley experiment from 1887 and Kennedy-Thorndike experiment from 1932 demonstrated that the universal frame of reference (ether) does not exist and that the velocity of light in vacuum is absolutely constant. The analysis of this experiment led to the creation of the Special Theory of Relativity (STR). The article explains why Michelson-Morley and Kennedy-Thorndike experiments could not detect the universal frame of reference. In this article, a different transformation of time and position than the Lorentz transformation is derived on the basis of the geometric analysis of the Michelson-Morley and Kennedy-Thorndike experiments. The transformation is derived based on the assumption that the universal frame of reference (UFR) exists. UFR is a frame of reference in which the velocity of light is constant in every direction. In inertial frames of reference moving in the UFR, the velocity of light may be different. The article has derived the formula for relative speed and patterns for the maximum and minimum speed of light that can be measured in the inertial system. Finally, the anisotropy of the microwave background radiation has been explained by using the presented theory. According to the body kinematics model presented in this article, anisotropy of cosmic microwave background is the Doppler effect for observer moving in the UFR. 展开更多
关键词 Kinematics of Bodies universal Frame of Reference COORDINATE and time Transformation One-Way Speed of Light Anisotropy of COSMIC Microwave Background
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Space, Time, and the Creation of Universe
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作者 Zhi Gang Sha Rulin Xiu 《Journal of Philosophy Study》 2017年第2期66-74,共9页
The understanding about the creation of our universe is explored in many philosophies, natural sciences, religions, ideologies, traditions, and disciplines. Current natural science cannot answer this question at the f... The understanding about the creation of our universe is explored in many philosophies, natural sciences, religions, ideologies, traditions, and disciplines. Current natural science cannot answer this question at the fundamental level. In this work, we combine the ancient Chinese Tao wisdom about the creation with quantum physics. We propose that everything comes from the emptiness. Our universe is manifested from the emptiness through two pairs of duality measurements: space and time duality pair and inclusion and exclusion duality pair. From this understanding, we are able to derive one mathematic formula describing our universe. It also yields a new metaphysical approach to derive and interpret string theory as well as produce more testable predictions from string theory. This work gives a new way to understand and mathematically describe how our universe is created and evolved. It provides another way to comprehend the meaning and function of space and time. It indicates that our universe is manifested from the emptiness through human actions. Space and time is a pair of duality action and codes that help manifest our universe. It provides answer to an important philosophical question about whether and why we can understand and mathematically describe our universe. 展开更多
关键词 SPACE time creation of universe string theory Tao wisdom quantum physics measurement theory duality MANIFESTATION grand unification theory
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5D World-Universe Model Space-Time-Energy 被引量:3
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2015年第1期25-34,共10页
5D Space-Time-Energy World-Universe Model is a unified model of the World built around the concept of Medium, composed of massive particles (protons, electrons, photons, neutrinos, and dark matter particles). The Mode... 5D Space-Time-Energy World-Universe Model is a unified model of the World built around the concept of Medium, composed of massive particles (protons, electrons, photons, neutrinos, and dark matter particles). The Model provides a mathematical framework that enables precise calculation of medium-bound physical parameters: Hubble’s parameter, intergalactic plasma parameters, temperature of microwave background radiation and the rest mass of photons. This paper aligns the World-Universe Model (WUM) with the theoretical framework developed by Prof. P. S. Wesson, albeit assigning a new physical meaning to the fifth coordinate. In the World-Universe Model, the fifth dimension is associated with the total energy of the Medium of the World, and the gravitomagnetic parameter of the Medium serves as the dimension-transposing parameter. 展开更多
关键词 5D World-universe Model Space-time-Energy Medium of the World Intergalactic Plasma Microwave BACKGROUND Radiation Mass VARYING PHOTONS
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Emergence of Friedmann Equation of Cosmology of a Flat Universe from the Time-Energy Uncertainty Principle 被引量:1
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作者 Vernon Cooray Gerald Cooray Farhad Rachidi 《Journal of Modern Physics》 2017年第12期1979-1987,共9页
Friedmann equation of cosmology is based on the field equations of general relativity. Its derivation is straight-forward once the Einstein’s field equations are given and the derivation is independent of quantum mec... Friedmann equation of cosmology is based on the field equations of general relativity. Its derivation is straight-forward once the Einstein’s field equations are given and the derivation is independent of quantum mechanics. In this paper, it is shown that the Friedmann equation pertinent to a homogeneous, isotropic and flat universe can also be obtained as a consequence of the energy balance in the expanding universe between the positive energy associated with vacuum and matter, and the negative gravitational energy. The results obtained here is a clear consequence of the fact that the surface area of the Hubble sphere is proportional to the total amount of information contained within it. 展开更多
关键词 Friedmann Equation Expansion of the universE Vacuum ENERGY Dark ENERGY time-Energy Uncertainty PRINCIPLE Holographic PRINCIPLE HUBBLE Sphere
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Space-Time Universe versus Energy Driven Time Arrow Universe: Time-Neutrality Confronted with Fundamental Irreversibility
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作者 Helmut Tributsch 《Journal of Modern Physics》 2019年第8期1029-1064,共36页
A dynamic interpretation of quantum phenomena based on an energy driven time arrow requires a combined description of matter and information on matter. This information around matter turned out to be gravitation and t... A dynamic interpretation of quantum phenomena based on an energy driven time arrow requires a combined description of matter and information on matter. This information around matter turned out to be gravitation and the fact that a photon is continuously recycled via this information generates an always constant light velocity. These two phenomena, simple consequences of fundamental irreversibility, have mathematically been imposed on empty space for time-neutral spacetime in General Relativity theory. In an irreversible universe such a four-dimensional spacetime would not anymore be required. Another striking difference is the role of time. Clock-time, used in Relativity Theory and found to be relative, is not associated with a generation of changes, being only a scale for measuring changes, based on selected periodic phenomena. The real time in an irreversible world, action time, is the flow of action, as generated by the principle of least action, or, alternatively, the loss of information on the past. In contrast to clock-time, action time is invariant with respect to relativistic transformation and also facilitates self-organization of matter and information. Gravitation as information on matter with the aim of imposing the principle of least action also provides the link between quantum world and cosmology, which Relativity Theory cannot provide. Relevant aspects of both theoretical approaches, with special emphasis on already experimentally verified spacetime phenomena, are critically analysed. While Relativity Theory, which is relying on time-neutral laws, is applied to support a chaotically exploding Big Bang scenario, the fundamentally irreversible universe subject to an energy driven time arrow is characterized by self-organization of energy, matter and information yielding an intelligent and creative “Self-Image” universe, which is able to periodically regenerate itself. Arguments for a fundamentally irreversible energy driven nature include, apart from explaining experimental support for Relativity Theory differently, the simple, straightforward derivation from a dynamically interpreted principle of least action, the elimination of quantum and cosmological paradoxes and the more sensitive and flexible information-technology based (digital) nature of gravitation as compared with the analogue “bent space” gravitation. 展开更多
关键词 time-Neutrality IRREVERSIBILITY General Relativity Theory Big Bang universE SELF-IMAGE universE Information
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Computational uncertainty and optimal grid size and time step of the Lax-Friedrichs scheme for the 1D advection equation
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作者 Jing Cao Jianping Li Yanjie Li 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第3期46-51,共6页
本文对于应用Lax-Friedrichs格式数值求解一维平流方程,研究数值求解过程中产生的截断误差与舍入误差,以及两种误差逐层向高时间层传播的累积,得到新的数值解总误差上界的理论近似公式,以及最优格距和最优时间步长的理论公式.通过数值... 本文对于应用Lax-Friedrichs格式数值求解一维平流方程,研究数值求解过程中产生的截断误差与舍入误差,以及两种误差逐层向高时间层传播的累积,得到新的数值解总误差上界的理论近似公式,以及最优格距和最优时间步长的理论公式.通过数值算例验证了所得公式的可靠性。然后,发现了两种不同机器精度下最优时间步长之比满足的一个仅与机器精度有关的普适关系.最后,理论验证了在网格比固定的情况下,此问题满足数值计算的不确定性原理,以及在机器有限精度下最优时间步长的必然存在。 展开更多
关键词 Lax-Friedrichs格式 数值计算的不确定性原理 最优格距 最优时间步长 普适关系
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采用万向开关的马歇特锤击零时刻确定方法
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作者 陈瑞华 徐艺方 +2 位作者 章品晶 唐晓峰 田相林 《探测与控制学报》 CSCD 北大核心 2024年第2期115-118,共4页
针对电子时间引信马歇特锤击测试过程中信号检测时采用加速度传感器频繁故障问题,提出采用万向开关确定马歇特锤击零时刻。根据马歇特锤击试验条件选定了万向开关关键参数,并设计低通RC滤波电路,采用将万向开关固定于马歇特锤击头部位,... 针对电子时间引信马歇特锤击测试过程中信号检测时采用加速度传感器频繁故障问题,提出采用万向开关确定马歇特锤击零时刻。根据马歇特锤击试验条件选定了万向开关关键参数,并设计低通RC滤波电路,采用将万向开关固定于马歇特锤击头部位,锤击时通过模拟信号滤波电路模块对万向开关闭合信号进行滤波,并采用示波器或中断采集电路进行监测,实现锤击过载零时刻确定,为测试信号提供零时基准。实验测试结果表明,该方法能够有效测量电子时间引信起爆输出计时精度,其采用的硬件简单,工程可行性强,可靠性高,可完全替代加速度计产生零时刻的方案。 展开更多
关键词 引信 马歇特锤击试验 零时刻 万向开关
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试论宇宙、空间、物质、时间及其关系
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作者 刘佩军 《西部学刊》 2024年第14期159-162,共4页
人们对时间的概念会因不同学者的不同观点而显得模糊,时间属性也会因一些学术争议而无法统一。如果将还处在争议中的时间概念纳入宇宙概念,结果就会因时间概念模糊导致宇宙概念一同模糊起来。目前,人们对时间的看法是“过程”,即物质变... 人们对时间的概念会因不同学者的不同观点而显得模糊,时间属性也会因一些学术争议而无法统一。如果将还处在争议中的时间概念纳入宇宙概念,结果就会因时间概念模糊导致宇宙概念一同模糊起来。目前,人们对时间的看法是“过程”,即物质变化过程。物质在空间内存在,在空间内演化,没有空间内的物质变化,时间就无法被确认。显然,空间与时间是隶属关系,而非并列关系。如果抛开时间,单把空间对应宇宙,宇宙“轮廓”会清晰许多,人类意识和潜意识中的宇宙概念也明了很多,在空间与宇宙同域的概念下再去讨论宇宙问题,其大小或边界就替换成整体空间的大小或边界,时间就不再是宇宙要素,讨论宇宙起源或宇宙终结也没有意义,因为空间既不存在起源,也不存在终结。看清宇宙、空间、物质、时间之间的相互关系,将拥有不一样的宇宙观。 展开更多
关键词 宇宙 空间 物质 时间
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基于大数据分析的高校多媒体设备可靠性研究
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作者 史萌 刘青竹 《实验室研究与探索》 CAS 北大核心 2024年第4期224-230,共7页
随着教育事业发展,多媒体教学成为各高校最普遍、使用频率最高的教学模式。充分利用多媒体设备运行数据优化管理工作,延长设备使用寿命,降低设备维护成本,始终是教育技术部门关注的问题。通过对天津大学卫津路校区6年来多媒体设备报修... 随着教育事业发展,多媒体教学成为各高校最普遍、使用频率最高的教学模式。充分利用多媒体设备运行数据优化管理工作,延长设备使用寿命,降低设备维护成本,始终是教育技术部门关注的问题。通过对天津大学卫津路校区6年来多媒体设备报修数据进行统计分析,利用SPSS分析软件对2020和2021年的数据进行线性回归,分析总报修数量与年度使用时间和设备实际使用年限的线性相关性;基于平均故障间隔时间对近2年的硬件报修进行分设备类型统计,从概念引入到推导计算,均给出详细验证过程。结合对非硬件问题造成的软件报修的前5位问题进行详细分析,据此提出设备更新科学化,定期巡检规范化和培训方式多样化的对策建议。 展开更多
关键词 高校多媒体设备 可靠性 线性回归 平均故障间隔时间
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高校党史教育常态化的时代意义与实践路径
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作者 孟笑飞 《湖北开放职业学院学报》 2024年第20期128-130,共3页
习近平总书记多次强调要深刻总结党史育人经验,升华党史育人成果,建立党史育人常态化机制。党史教育常态化,是落实党的全面领导、落实高校“立德树人”根本任务以及坚定大学生理想信念的必然要求,可以深化马克思主义理论学习、优化思想... 习近平总书记多次强调要深刻总结党史育人经验,升华党史育人成果,建立党史育人常态化机制。党史教育常态化,是落实党的全面领导、落实高校“立德树人”根本任务以及坚定大学生理想信念的必然要求,可以深化马克思主义理论学习、优化思想政治教育体系以及弘扬中华优秀传统文化。高校党史教育通过以思政课教育教学为主线、以深化学习教育为保障、以弘扬中华优秀传统文化为拓展,协同打造新时代高校党史教育的协同机制、育人机制和载体机制。 展开更多
关键词 高校 党史教育 时代意义 实践路径
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西南联大教师兼职研究
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作者 刘超 罗冠群 《云南师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2024年第4期137-148,共12页
在时空不稳定的战争时期,西南联合大学的教学与研究资源受到限制,大后方物价的飞涨导致教师生活难以为继,联大教师相继兼职。这种兼职产生了多方面影响:在一定程度上,主业时间的压缩不可避免地影响了教学工作;学者的社会参与和市场活动... 在时空不稳定的战争时期,西南联合大学的教学与研究资源受到限制,大后方物价的飞涨导致教师生活难以为继,联大教师相继兼职。这种兼职产生了多方面影响:在一定程度上,主业时间的压缩不可避免地影响了教学工作;学者的社会参与和市场活动改变了其生活样态和思想观念,推动了近代大学价值取向的变迁,使大学的社会服务功能进一步凸显,大学的学术体制在教师的流动中也有所调适;文化资源的流入与再生,则带动了西南地区政治、经济和文化的发展。 展开更多
关键词 西南联合大学 教师兼职 学术环境 精神再造 在地化
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