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Perception of fundamental science to boost lithium metal anodes toward practical application
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作者 Jinkun Wang Li Wang +2 位作者 Hong Xu Li Sheng Xiangming He 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第3期454-472,共19页
As a key material for lithium metal batteries(LMBs),lithium metal is one of the most promising anode materials to break the bottleneck of battery energy density and a commonly used active material for reference electr... As a key material for lithium metal batteries(LMBs),lithium metal is one of the most promising anode materials to break the bottleneck of battery energy density and a commonly used active material for reference electrodes.Although lithium anodes are regarded as the holy grail of lithium batteries,decades of exploration have not led to the successful commercialization of LMBs,due mainly to the challenges related to the inherent properties of lithium metal.To pave the way for further investigation,herein,a comprehensive review focusing on the fundamental science of lithium are provided.Firstly,the natures of lithium atoms and their isotopes,lithium clusters and lithium crystals are revisited,especially their structural and energetic properties.Subsequently,the electrochemical properties of lithium metal are reviewed.Numerous important concepts and scientific questions,including the electronic structure of lithium,influence of high pressure and low temperature on the properties of lithium,factors influencing lithium deposition,generation of lithium dendrites,and electrode potential of lithium in different electrolytes,are explained and analyzed in detail.Approaches to improve the performance of lithium anodes and thoughtfulness about the electrode potential in lithium battery research are proposed. 展开更多
关键词 LITHIUM CLUSTER Crystal Physicochemical property fundamental science
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New Approach to Synchronize General Relativity and Quantum Mechanics with Constant “K”-Resulting Dark Matter as a New Fundamental Force Particle
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作者 Siva Prasad Kodukula 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期292-302,共11页
Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction a... Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction and expansion forces of space time. According to this, the space time with Planck diameter is a flat space time. This is the only diameter of space time that can be used as signal transformation in special relativity. This space time diameter defines the fundamental force which belongs to that space time. In quantum mechanics, this space time diameter is only the quantum of space which belongs to that particular fundamental force. Einstein’s general relativity equation and Planck parameters of quantum mechanics have been written in terms of equations containing a constant “K”, thus found a new equation for transformation of general relativity space time in to quantum space time. In this process of synchronization, there is a possibility of a new fundamental force between electromagnetic and gravitational forces with Planck length as its space time diameter. It is proposed that dark matter is that fundamental force carrying particle. By grand unification equation with space-time diameter, we found a coupling constant as per standard model “α<sub>s</sub>” for that fundamental force is 1.08 × 10<sup>-23</sup>. Its energy calculated as 113 MeV. A group of experimental scientists reported the energy of dark matter particle as 17 MeV. Thorough review may advance science further. 展开更多
关键词 General Relativity Quantum Mechanics Space Time Dark Matter A New fundamental Constant “K”
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Performance in the Fundamentals of Laparoscopic Surgery: Does it reflect global rating scales in the Objective Structured Assessment of Technical Skills in porcine laparoscopic surgery?
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作者 Ho Yee Tiong Wei Zheng So +10 位作者 Jeremy Yuen-Chun Teoh Shuji Isotani Gang Zhu Teng Aik Ong Eddie Shu-Yin Chan Peggy Sau-Kwan Chu Kittinut Kijvikai Ming Liu Bannakji Lojanapiwat Michael Wong Anthony Chi-Fai Ng 《Asian Journal of Urology》 CSCD 2024年第3期443-449,共7页
Objective:To correlate the utility of the Fundamentals of Laparoscopic Surgery(FLS)manual skills program with the Objective Structured Assessment of Technical Skills(OSATS)global rating scale in evaluating operative p... Objective:To correlate the utility of the Fundamentals of Laparoscopic Surgery(FLS)manual skills program with the Objective Structured Assessment of Technical Skills(OSATS)global rating scale in evaluating operative performance.Methods:The Asian Urological Surgery Training and Educational Group(AUSTEG)Laparoscopic Upper Tract Surgery Course implemented and validated the FLS program for its usage in laparoscopic surgical training.Delegates’basic laparoscopic skills were assessed using three different training models(peg transfer,precision cutting,and intra-corporeal suturing).They also performed live porcine laparoscopic surgery at the same workshop.Live surgery skills were assessed by blinded faculty using the OSATS rating scale.Results:From March 2016 to March 2019,a total of 81 certified urologists participated in the course,with a median of 5 years of post-residency experience.Although differences in task time did not reach statistical significance,those with more surgical experience were visibly faster at completing the peg transfer and intra-corporeal suturing FLS tasks.However,they took longer to complete the precision cutting task than participants with less experience.Overall OSATS scores correlated weakly with all three FLS tasks(peg transfer time:r=0.331,r^(2)=0.110;precision cutting time:r=0.240,r^(2)=0.058;suturing with intracorporeal knot time:r=0.451,r^(2)=0.203).Conclusion:FLS task parameters did not correlate strongly with OSATS globing rating scale performance.Although FLS task models demonstrated strong validity,it is important to assimilate the inconsistencies when benchmarking technical proficiency against real-life operative competence,as evaluated by FLS and OSATS,respectively. 展开更多
关键词 The fundamentals of Laparoscopic Surgery Assessment of Technical Skills Laparoscopic training Surgical education Surgical training Urological laparoscopic surgery
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Fundamental Principles behind Climate Change
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作者 Haiyan DAI 《Meteorological and Environmental Research》 2024年第4期21-23,共3页
The attribution of climate change is complex,and the current mainstream view is more inclined towards human activities and carbon dioxide emissions from fossil fuels.Any complex problem is composed of basic principles... The attribution of climate change is complex,and the current mainstream view is more inclined towards human activities and carbon dioxide emissions from fossil fuels.Any complex problem is composed of basic principles.This article elaborates on the basic logic behind climate change(a global hot topic)through basic principles such as reaction types,carbon thermal properties of biomass energy,greenhouse gas attribution,ecological basic theory,and energy cycle. 展开更多
关键词 Climate change Feedback mechanisms fundamental principles DISASTERS
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The Intervention Path of Fundamental Rights under the Scope of International Private Law
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作者 何叶华 SHEN Jinjun(Translated) 《The Journal of Human Rights》 2024年第2期373-392,共20页
In recent years, international private law scholars have argued for the radiating effect of fundamental rights on international private law by introducing constitutional theory. However,there remains a lack of systema... In recent years, international private law scholars have argued for the radiating effect of fundamental rights on international private law by introducing constitutional theory. However,there remains a lack of systematic research on how fundamental rights should be integrated into judicial practices concerning foreign-related civil and commercial cases. Throughout the development of international private law, public policy has served as a historical carrier of substantive values for judicial entities and has consistently played a crucial role in value review. In cases of international private law where conflicts arise with the values of fundamental rights, public policy indirectly excludes the legal choice outcomes to safeguard the human rights values inherent in fundamental rights from infringement.However, due to limitations imposed by the degree of connection and relative conditions, traditional paths of public policy have certain constraints and cannot provide comprehensive protection for fundamental rights. Therefore, there is a need for judges to shift their logical paradigms, transcend bilateral choice-of-law models, and introduce a direct intervention path for fundamental rights. This direct intervention path utilizes the logical analysis framework of the protection scope,intervention, and justification of fundamental rights. It can effectively balance conflicting legal interests and maximize the protection of the fundamental rights of the parties involved. 展开更多
关键词 fundamental rights intervention path public policy analysis framework
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Frame Length Dependency for Fundamental Frequency Extraction in Noisy Speech
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作者 Md. Saifur Rahman Any Chowdury +2 位作者 Nargis Parvin Arpita Saha Moinur Rahman 《Journal of Signal and Information Processing》 2024年第1期1-17,共17页
The fundamental frequency plays a significant part in understanding and perceiving the pitch of a sound. The pitch is a fundamental attribute employed in numerous speech-related works. For fundamental frequency extrac... The fundamental frequency plays a significant part in understanding and perceiving the pitch of a sound. The pitch is a fundamental attribute employed in numerous speech-related works. For fundamental frequency extraction, several algorithms have been developed which one to use relies on the signal’s characteristics and the surrounding noise. Thus, the algorithm’s noise resistance becomes more critical than ever for precise fundamental frequency estimation. Nonetheless, numerous state-of-the-art algorithms face struggles in achieving satisfying outcomes when confronted with speech recordings that are noisy with low signal-to-noise ratio (SNR) values. Also, most of the recent techniques utilize different frame lengths for pitch extraction. From this point of view, This research considers different frame lengths on male and female speech signals for fundamental frequency extraction. Also, analyze the frame length dependency on the speech signal analytically to understand which frame length is more suitable and effective for male and female speech signals specifically. For the validation of our idea, we have utilized the conventional autocorrelation function (ACF), and state-of-the-art method BaNa. This study puts out a potent idea that will work better for speech processing applications in noisy speech. From experimental results, the proposed idea represents which frame length is more appropriate for male and female speech signals in noisy environments. 展开更多
关键词 Pitch Estimation fundamental Frequency BaNa ACF Frame Length
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Seismology in the Light of Fundamental Sciences
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作者 Bychkov Serguei 《Open Journal of Earthquake Research》 2024年第1期84-112,共29页
According to the definition, seismology is a science that studies the processes and causes of seismic phenomena and the structure of the Earth, i.e. a scientific discipline that studies the movement of blocks of rocks... According to the definition, seismology is a science that studies the processes and causes of seismic phenomena and the structure of the Earth, i.e. a scientific discipline that studies the movement of blocks of rocks of the Earth’s crust and mantle and related phenomena. Seismology conducts research in the following areas and is designed to scientifically explain two main issues: 1) Study of the nature of seismic phenomena and the internal structure of the Earth. Why, how and where do seismic impacts occur? 2) Protecting humanity from the catastrophic consequences of seismic events. Is it possible to predict seismic impacts? Like any other scientific discipline, seismology is obliged to follow the laws of science and its fundamental principles. This article is devoted to the description of violations of the fundamental laws of science committed by seismologists in the study of seismic processes and raises the question of compliance of the stated research directions with the current level of development of sciences. Answering point No. 1, regarding the structure of the Earth, it is possible to recognize some successes of seismology, which nevertheless cause great doubts in the scientific community of geophysicists, because if the stratigraphic data of ultra-deep wells often refute [1] the conclusions made by seismologists on the structure of the Earth’s crust at shallow depth, then to assert something unambiguously about the structure of the mantle and at the present stage, seismology cannot. Answering the main questions of seismology, why seismic phenomena occur, and how earthquake energy is formed, seismologists have not had, and have not. Answering point No. 2, we can confidently say that in the matter of forecasting seismic phenomena, seismology has not advanced one iota over the past century, and as seismologists have been confused in the search for earthquake prediction algorithms, they are also confused without any hope of success. All that modern seismology can “boast” is the theory of Elastic recoil [2], the absurdity of which does not cause any doubt among the progressive part of geophysicists. But, the fact that most of the leading scientists-seismologists continue to piously believe the conclusions of the Elastic Recoil theory puts seismology in a humiliating position, because Mr. Reid’s theory is the clearest example of a false theory based on scientific incompetence of scientists, a model of brazen violation of the fundamental laws of science and the foundation of false and ignorant conclusions. Based on the results achieved, or rather on their absence, we regret to draw a sad conclusion: modern seismology is in the deepest decline, the cause of which is the incompetence of researchers as a result of their catastrophically low level of academic training, who stuff the scientific community with scientific geophysical rubbish, breeding similar ignoramuses in seismology. We understand that by asserting this, we offend most seismologists, but it is impossible to continue to tolerate this state of affairs in geophysics, because: “Amicus plato, sed magis amica est veritas.” Obviously, the time has come for a new meteorologist, Alfred Wagener [3], who will come and teach seismologists not to guess on coffee grounds, but to investigate seismic processes using the fundamental laws of science. In this article, we not only investigate the reasons for the unsatisfactory state of affairs in seismology, but also give our answers to the questions, of why earthquakes occur and how seismic energy is formed. 展开更多
关键词 SEISMOLOGY EARTHQUAKE fundamental Laws of Science
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Effect of simulating training of the fundamentals of laparoscopic surgery on the attitude of operating room nurses students:an intervention study
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作者 Reza Mohebbi Armin Fereidouni +1 位作者 Sedigheh Hannani Esmaeil Teymoori 《Frontiers of Nursing》 2024年第3期295-302,共8页
Objective:Clinical education plays a key role in preparing students for patient care.Laparoscopy is one of the most important minimally invasive surgeries(MISs)wherein surgical technologists are responsible for camera... Objective:Clinical education plays a key role in preparing students for patient care.Laparoscopy is one of the most important minimally invasive surgeries(MISs)wherein surgical technologists are responsible for camera navigation and assistant surgeons are responsible for peg transfer.Therefore,it is necessary to improve the attitude of the operating room students toward these skills during their study period.The present study was conducted to determine the effect of simulating training in the fundamentals of laparoscopic surgery(FLS)on the attitude of the operating room students.Methods:This interventional study was conducted on 28 operating room students of Iran University of Medical Sciences in 2019.The census sampling method was used.The data-collection tool included the“Intrinsic motivation inventory(IMI)questionnaire.”The educational intervention was carried out in theoretical(booklet design)and practical(simulation)sections.Data analysis was carried out using descriptive and inferential analyses including the paired t-test,Mann–Whitney U test,and independent t-test.The collected data were analyzed using R and SPSS software.P-value<0.05 was considered as the significant level.Results:The mean±SD of the participants'age was 22.93±2.14 years,and the majority of them were women(67.9%).There was a significant difference in the mean scores of students'attitudes toward the FLS before and after the educational intervention(P<0.001)in all dimensions(interest,perceived competence,perceived choice,and tension).There was also a significant correlation between gender and interest dimension(P=0.005).Conclusions:The results of the present study showed that simulating the training FLS curriculum positively affects students'attitudes.Therefore,the researchers suggest that for creating a positive attitude,increasing students'interest in laparoscopic surgery,and ensuring a more effective presence in the operating room,this training should be considered in the operating room curriculum. 展开更多
关键词 ATTITUDE education fundamentals of laparoscopic surgery nurse operating room students STIMULATION
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Fundamental Physical Constants and Primary Physical Parameters
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第1期190-209,共20页
Every four years the Committee on Data for Science and Technology (CODATA) supplies a self-consistent set of values of the basic constants and conversion factors of physics recommended for international use. In 2013, ... Every four years the Committee on Data for Science and Technology (CODATA) supplies a self-consistent set of values of the basic constants and conversion factors of physics recommended for international use. In 2013, the World-Universe Model (WUM) proposed a principally different depiction of the World as an alternative to the picture of the Big Bang Model. This article: 1) Gives the short history of Classical Physics before Special Relativity;2) Calculates Fundamental Physical Constants based on experimentally measured Rydberg constant, Electrodynamic constant, Electron Charge-to-Mass Ratio, and Planck constant;3) Discusses Electrodynamic constant and Speed of Light;4) Considers Dimensionless Fundamental Parameters (Dirac Large Number Q and Dimensionless Rydberg Constant α);5) Calculates Newtonian Constant of Gravitation based on the Inter-connectivity of Primary Physical Parameters;6) Makes a detailed analysis of the Self-consistency of Fundamental Physical Constants and Primary Physical Parameters through the prism of WUM. The performed analysis suggests: 1) Discontinuing using the notion “Vacuum” and its characteristics (Speed of Light in Vacuum, Characteristic Impedance of Vacuum, Vacuum Magnetic Permeability, Vacuum Electric Permittivity);2) Accepting the exact numerical values of Electrodynamic constant, Planck constant, Elementary charge, and Dimensionless Rydberg Constant α. WUM recommends the predicted value of Newtonian Constant of Gravitation in 2018 to be considered in CODATA Recommend Values of the Fundamental Physical Constants 2022. 展开更多
关键词 Classical Physics fundamental Physical Constants Electrodynamic Constant Speed of Light Dirac Large Number Dimensionless Rydberg Constant Newtonian Constant of Gravitation Self-Consistency of fundamental Physical Constants
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The Significance of Generalized Gauge Transformation across Fundamental Interactions
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作者 Bi Qiao 《Journal of Modern Physics》 CAS 2023年第5期604-622,共19页
The author of this paper has put forward a unified program of gauge field from the mathematical and physical picture of the principal associated bundles: thinking that our universe may have more fundamental interactio... The author of this paper has put forward a unified program of gauge field from the mathematical and physical picture of the principal associated bundles: thinking that our universe may have more fundamental interactions than the four fundamental interactions, and these basic interaction gauge fields are only the projection components to the base manifold, that is our universe, from a unified gauge potential or connection of the principal associated bundle manifold on the base manifold. These components can satisfy the transformation of gauge potential, and can even be transformed from one basic interaction gauge potential to another basic interaction gauge potential, and can be summarized into a unified equation, that is, the generalized gauge Equation (GGE), but the gauge potential or connection on the principal bundle is invariant, corresponding to the invariance of gauge transformation [1]. In this paper, we will continue to discuss this aspect concretely, and specifically construct a spatiotemporal model with the frame bundle as the principal bundle, and the tensor bundle as the associated bundle, so that the four fundamental interactions, especially the electromagnetic interaction and the gravitational interaction, can be reflected in the bottom manifold, that is, the regional distributions in our universe. Furthermore, this paper studies the existence of gauge transformation across basic interactions by establishing a model of gauge transformation of basic interaction field;it is found that the unified expression formula is GGE and the expression relation on the curvature of space-time. Therefore, the author discusses the feasibility of the generalized gauge transformation across the basic electromagnetic interaction and the basic gravitational interaction, and on this basis, specifically determines a method or way to find the generalized gauge transformation, so as to try to realize the last step of the “unification” of the four fundamental interactions in physics, that is, the “unification” of electromagnetism and gravity. 展开更多
关键词 Generalized Gauge Transformation Unification of fundamental Interactions Principal Bundle Connection and Curvature
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Supreme Theory of Everything: The Fundamental Forces in Quantum Hysteresis
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作者 Tardad Ulaanbaatar 《Journal of Applied Mathematics and Physics》 2023年第10期3274-3285,共12页
Gravity is considered one of the most mysterious of the four fundamental forces, a well-studied but poorly understood phenomenon in science. Newtonian physics and General Relativity have studied it from outside. Based... Gravity is considered one of the most mysterious of the four fundamental forces, a well-studied but poorly understood phenomenon in science. Newtonian physics and General Relativity have studied it from outside. Based on fundamental forces the Grand Unified Theory (GUT) and the Standard Model (SM) of Particle Physics study from the inside. GUT and SM explain three fundamental forces that govern the universe: electromagnetism, the strong force, and the weak force. The fourth fundamental force hopes that must be gravity, which the SM cannot adequately explain. The research aims to explain fundamental forces and their interactions based on the hysteresis law. The hysteresis law studies the fundamental forces from both inside and outside, so, I hope it can explain the rules and principles of the universe from the microworld to the macroscopic world. The united force of the three fundamental forces in high energy singularity (vertical asymptote) of the hysteresis becomes the weakest like weak interaction and continuously like strong force but has an infinite range like electromagnetic interaction. In this sense, it may be called gravity. Unfortunately, gravity is not an individual force;it is the positive singularity or high energy asymptotic sum of three fundamental forces emerging from the depth of the hysteresis of the subatomic particles. 展开更多
关键词 The fundamental Forces Alternative Fermi-Dirac Distribution The Vertical Asymptote of Hysteresis GRAVITY
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Teaching Reform of Fundamentals of Combustion for Energy and Power Engineering Majors in Agricultural Colleges and Universities in the Context of New Engineering Course
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作者 Shengyang GAO Yanhua MA 《Asian Agricultural Research》 2023年第11期46-49,共4页
The Fundamentals of Combustion course is an important compulsory course for Energy and Power Engineering Majors under the background of carbon peaking.According to the characteristics of teaching and scientific resear... The Fundamentals of Combustion course is an important compulsory course for Energy and Power Engineering Majors under the background of carbon peaking.According to the characteristics of teaching and scientific research at present,combined with the characteristics of complexity,interdisciplinary and rapid technology update of this course,this paper discusses the teaching content and teaching design of this course to meet the needs of talents of production,teaching and research under the background of new engineering course.It proposes more applicable teaching methods and practical means to broaden students horizons,stimulate students autonomous learning momentum,master the professional knowledge application ability,and cultivate innovative and competitive engineering professionals to adapt to the new energy strategy. 展开更多
关键词 New engineering course fundamentals of Combustion Undergraduate education Practice teaching Curriculum reform
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Large Scale Fundamental Interactions in the Universe
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作者 Qiao Bi 《Journal of Modern Physics》 2023年第S1期1703-1720,共18页
The author of this paper once attempted to propose a unified framework for gauge fields based on the mathematical and physical picture of the principal fiber bundle: that is, to believe that our universe may have more... The author of this paper once attempted to propose a unified framework for gauge fields based on the mathematical and physical picture of the principal fiber bundle: that is, to believe that our universe may have more fundamental interactions than the four, and these fundamental gauge fields are only components on the bottom manifold (i.e. our universe) projected by a unified gauge potential of the principal fiber bundle manifold;these components can satisfy the transformation of gauge potential, or even be transformed from one basic interaction gauge potential to another basic interaction gauge potential, and can be summarized into a unified equation, namely the generalized gauge equation expression, corresponding to gauge transformation invariance;so the invariance of gauge transformation is a necessary condition for unified field theory, and the four (or more) fundamental interaction fields of the universe are unified in a unified gauge field defined by the connection on the principal fiber bundle. In this paper, the author continues to propose a model of large-scale (gravitational) fundamental interactions in the universe based on the mathematical and physical picture of the principal fiber bundle, attempting to explain that dark matter and dark energy are merely reflections of these gravitational fundamental interactions that deviate in intensity from the gravitational fundamental interactions of the solar system at galaxy scales or some cosmic scales which are much larger than the solar system. All these “gravitational” fundamental interactions originate from the unified gauge field of the universe, namely the connection or curvature on the principal fiber bundle. These interactions are their projected representations on the bottom manifold (i.e. our universe) by different cross-sections (gauge transformations). These projection representations of the universe certainly are described by the generalized gauge equation or curvature similarity equation, and under the guidance of curvature gauge transformation factors, oscillate and evolve between the curvatures 1→0→-1→0→1 of the universe. 展开更多
关键词 Principal Bundle Gauge Similarity Transformation Dark Matter and Dark Energy Large-Scale fundamental Interaction Evolution of Universe
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Unenumerated Rights Clauses and the System of Restriction on Fundamental Rights——Another Construction Plan for Article 51 of the Constitution of PRC
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作者 杜强强 QIAN Chuijun 《The Journal of Human Rights》 2023年第1期91-108,共18页
According to constitutional jurisprudence in China,Article 51 of the Constitution is an unenumerated restrictive clause.Such theoretical construction fails to justify the differentiated restrictions established in the... According to constitutional jurisprudence in China,Article 51 of the Constitution is an unenumerated restrictive clause.Such theoretical construction fails to justify the differentiated restrictions established in the Constitution and makes it difficult to explain the constitutional status of human dignity. Article 51 implies the possibility of other theoretical constructions. It is not an unenumerated restriction clause but an unenumerated rights clause. It aims to provide guarantees for general freedom of action not enumerated in the Constitution rather than restricting fundamental rights. The actual benefit of this kind of theoretical construction lies in that it can establish the basis of the constitutional text for general freedom of action and promote the people’s correct understanding of the model of restriction on fundamental rights established by the Constitution of PRC. 展开更多
关键词 restriction on fundamental rights ¿legal construction ¿general freedom of action
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On Some Fundamental Theorems in Stability Theory 被引量:24
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作者 徐道义 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期61-67,共7页
This paper gives several fundamental theorems for the stability, uniform stability, asymptotic stability and uniform asymptotic stability. Those theorems allow the derivative of Lyapunov functions to be positive on ce... This paper gives several fundamental theorems for the stability, uniform stability, asymptotic stability and uniform asymptotic stability. Those theorems allow the derivative of Lyapunov functions to be positive on certain sets,relax the restriction about the rate of change of state variable in a system to be bounded in Marachkov's theorem and extend the related results in [4—7]. 展开更多
关键词 STABILITY Lyapunov fundamental theorem nonautonomous differential equations
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Study of macroscopic fundamental diagram on Shanghai urban expressway network in China 被引量:2
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作者 石心怡 林航飞 《Journal of Southeast University(English Edition)》 EI CAS 2016年第1期106-111,共6页
The macroscopic fundamental diagram( MFD) is studied to obtain the aggregate behavior of traffic in cities. This paper investigates the existence and the characteristics of different types of daily MFD for the Shang... The macroscopic fundamental diagram( MFD) is studied to obtain the aggregate behavior of traffic in cities. This paper investigates the existence and the characteristics of different types of daily MFD for the Shanghai urban expressway network. The existence of MFD in the Shanghai urban expressway network is proved based on two weeks' data.Moreover, the hysteresis phenomena is present in most days and the network exhibits different hysteresis loops under different traffic situations. The relationship between the hysteresis phenomena and the inhomogeneity of traffic distribution is verified. The MFDs in the years of 2009 and 2012 are compared. The hysteresis loop still exists in 2012, which further verifies the existence of the hysteresis phenomenon. The direct relationship between the length of the hysteresis loop( ΔO) and the congestion is proved based on sufficient data. The width of the hysteresis loop, i. e., the drop in network flow( ΔQ) has no relationship with the congestion, and it varies from day to day under different traffic situations. 展开更多
关键词 macroscopic fundamental diagram(MFD) hysteresis phenomena urban expressway network index of congestion
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Fast estimation of fundamental matrix based on stripe constraints
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作者 杨安康 刘京南 +1 位作者 内田敬久 内田悦行 《Journal of Southeast University(English Edition)》 EI CAS 2008年第4期473-477,共5页
In order to improve the performance of estimating the fundamental matrix, a key problem arising in stereo vision, a novel method based on stripe constraints is presented. In contrast to traditional methods based on al... In order to improve the performance of estimating the fundamental matrix, a key problem arising in stereo vision, a novel method based on stripe constraints is presented. In contrast to traditional methods based on algebraic least-square algorithms, the proposed approach aims to minimize a cost function that is derived from the minimum radius of the Hough transform. In a structured-light system with a particular stripe code pattern, there are linear constraints that the points with the same code are on the same surface. Using the Hough transform, the pixels with the same code map to the Hough space, and the radius of the intersections can be defined as the evaluation function in the optimization progress. The global optimum solution of the fundamental matrix can be estimated using a Levenberg- Marquardt optimization iterative process based on the Hough transform radius. Results illustrate the validity of this algorithm, and prove that this method can obtain good performance with high efficiency. 展开更多
关键词 fundamental matrix structured-light stripe code pattern stereo vision
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Observation of Fundamental and High Order Raman Modes of β-Carotenes in Pd OECC Thin Film by SERS
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作者 刘玉龙 刘金全 +4 位作者 朱恪 杨国桢 单际修 李良璧 匡廷云 《Acta Botanica Sinica》 CSCD 2000年第12期1231-1234,共4页
Raman spectra of purified oxygen evolution core complexes (Pd OECC) thin films on silver mirror substrates have been taken over the frequency range of 250-3100 cm -1 by surface enhanced Raman scattering (SERS). B... Raman spectra of purified oxygen evolution core complexes (Pd OECC) thin films on silver mirror substrates have been taken over the frequency range of 250-3100 cm -1 by surface enhanced Raman scattering (SERS). Besides the fundamental frequency modes of β_carotene in Pd OECC, many weak peaks are observed. According to the selection rules of overtone and combination bands, most of them are attributed to the second_order Raman spectra of β_carotene. Compared with the SERS of normal Pd OECC, the SERS of Pd OECC after strong illumination shows a decrease in scattering intensity and an increase in line widths, indicating changes of conformation and micro_environment of β_carotene. The results of SERS are consistent with the changes of absorption spectrum of Pd OECC induced by strong illumination. There are no changes that can be ascribed to new vibration bands, so it is deduced that Pd OECC on the silver mirror is identical to that in the solution. In summary, SERS proved a good method to study the photodamage mechanism of photosynthesis. 展开更多
关键词 SERS photosynthesis photodamage Β-CAROTENE fundamental and high order Raman modes
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高等教育出版社最新引进的Fundamentals of Chemistry
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作者 卞江 《大学化学》 CAS 2004年第3期61-62,共2页
关键词 书评 高校 化学教材 《化学基础》 fundamentals of Chemistry》 教材内容 目标读者
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Fundamental motor skills,screen-time,and physical activity in preschoolers 被引量:16
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作者 E.Kipling Webster Corby K.Martin Amanda E.Staiano 《Journal of Sport and Health Science》 SCIE 2019年第2期114-121,共8页
Purpose: To examine the associations among preschoolers fundamental motor skills, screen-time, physical activity(PA), and sedentary behavior(SB).Methods: Children ages 3à4 years were enrolled in a prospective obs... Purpose: To examine the associations among preschoolers fundamental motor skills, screen-time, physical activity(PA), and sedentary behavior(SB).Methods: Children ages 3à4 years were enrolled in a prospective observational trial of PA. Trained assessors conducted the Test of Gross Motor Development-3 rd edition(TGMD-3), and the Movement Assessment Battery for Children-2 nd edition, and parent-reported child screen-time and sociodemographic information. Children wore an accelerometer for 7 days to examine SB and total PA(TPA). TPA was further characterized as moderateto-vigorous PA(MVPA) or vigorous PA(VPA). Mixed linear models were calculated, controlling for age(for TGMD-3), sex, household income, and accelerometer wear time(for accelerometry models), with childcare center as a random effect. The primary analysis reported on the cross-sectional baseline data of 126 children with complete fundamental motor skill and screen-time data; a subanalysis included 88 children with complete accelerometry data.Results: Children were 3.4 § 0.5 years of age(54% girls; 46% white, 42% African American, 12% other). A total of 48% lived in households at or below the federal poverty level. Children engaged in 5.1 § 3.6 h/day of screen-time. Children's screen-time was inversely related to the Movement Assessment Battery for Children-2 nd edition, manual dexterity skills percentile(b(SE) = ?1.7(0.8), p = 0.049). In the accelerometry subsample,children engaged in 5.9 § 0.9 h/day of TPA of which 1.7 § 0.6 h/day was MVPA. Boys engaged in more MVPA and VPA and less SB compared with girls(all p < 0.05). A higher TGMD-3, total score(b(SE) = 0.4(0.2), p = 0.017) and locomotor score(b(SE) = 0.7(0.3), p = 0.018) were associated with more VPA but not with TPA or MVPA. Screen-time and television in the bedroom were not related to SB, TPA, MVPA, or VPA.Conclusion: Children's motor skills were positively related to VPA but inversely related to screen-time. Further inquiry into the implications of high exposure to screen-time in young children is needed. 展开更多
关键词 fundamental motor SKILLS Physical activity PRESCHOOL Screen-time
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