The challenge in searching for fundamental symmetry violation.Neutrinoless double-beta(0νββ)decay represents one of the most profound tests of fundamental symmetries in nature.This hypothetical nuclear process,in w...The challenge in searching for fundamental symmetry violation.Neutrinoless double-beta(0νββ)decay represents one of the most profound tests of fundamental symmetries in nature.This hypothetical nuclear process,in which two neutrons simultaneously decay into two protons with the emission of two electrons but no neutrinos,would demonstrate that lepton number is not conserved and confirm that neutrinos are their own antiparticles(Majorana particles).The observation of 0νββdecay would provide crucial insights into the absolute neutrino mass scale and could illuminate the origin of matter-antimatter asymmetry in the universe.展开更多
Moirésystems have emerged as an ideal platform for exploring interaction effects and correlated states.However,most of the experimental systems are based on either triangular or honeycomb lattices.In this study,b...Moirésystems have emerged as an ideal platform for exploring interaction effects and correlated states.However,most of the experimental systems are based on either triangular or honeycomb lattices.In this study,based on the self-consistent Hartree–Fock calculation,we investigate the phase diagram of the kagomélattice in a recently discovered system with two degenerateΓvalley orbitals and strong spin–orbit coupling.By focusing on the filling factors of 1/2,1/3 and 2/3,we identify various symmetry-breaking states by adjusting the screening length and dielectric constant.At the half filling,we discover that the spin–orbit coupling induces Dzyaloshinskii–Moriya interaction and stabilizes a classical magnetic state with 120°ordering.Additionally,we observe a transition to a ferromagnetic state with out-of-plane ordering.In the case of 1/3 filling,the system is ferromagnetically ordered due to the lattice frustration.Furthermore,for 2/3 filling,the system exhibits a pinned droplet state and a 120°magnetic ordered state at weak and immediate coupling strengths,respectively.For the strong coupling case,when dealing with non-integer filling,the system is always charge ordered with sublattice polarization.Our study serves as a starting point for exploring the effects of correlation in moirékagomésystems.展开更多
The statistical parameters of five generalizations of the Lindley distribution, such as the average, variance and moments, are reviewed. A new double truncated Lindley distribution with three parameters is derived. Th...The statistical parameters of five generalizations of the Lindley distribution, such as the average, variance and moments, are reviewed. A new double truncated Lindley distribution with three parameters is derived. The new distributions are applied to model the initial mass function for stars.展开更多
We demonstrate that certain astrophysical distributions can be modelled with the truncated Weibull distribution, which can lead to some insights: in particular, we report the average value, the <em>r</em>t...We demonstrate that certain astrophysical distributions can be modelled with the truncated Weibull distribution, which can lead to some insights: in particular, we report the average value, the <em>r</em>th moment, the variance, the median, the mode, the generation of random numbers, and the evaluation of the two parameters with maximum likelihood estimators. The first application of the Weibull distribution is the initial mass function for stars. The magnitude version of the Weibull distribution is applied to the luminosity function for the Sloan Digital Sky Survey (SDSS) galaxies and to the photometric maximum of the 2MASS Redshift Survey (2MRS) galaxies. The truncated Weibull luminosity function allows us to model the average value of the absolute magnitude as a function of the redshift for the 2MRS galaxies.展开更多
Purpose: Increasing physician awareness of patient exposure to radiation is an important step towards the reduction of potentially harmful effects of radiation. Published studies demonstrated that providing physicians...Purpose: Increasing physician awareness of patient exposure to radiation is an important step towards the reduction of potentially harmful effects of radiation. Published studies demonstrated that providing physicians with feedback regarding their fluoroscopy time leads to a reduction in average fluoroscopy times. The aim of this work was to analyze and publish our medical center data observed during the past year;fluoroscopy time (FT), Dose Area Product (DAP) and cumulative dose (CD) were monitored for radiation protection purposes. Methods: Fluoroscopy time is one of multiple radiation dose indices used in radiation safety auditing. Such auditing is nowadays turning into requirement of patient care safety and quality improvement;as indicated by accreditation bodies both nationally and internationally. All non-cardiac procedures performed outside radiology department by surgeons and interventionists are viewed. FT, DAP and CD are extracted for analysis. Results: a total of 846 cases were studied (643 orthopedic, 99 others, 73 urology, 17 chest, 7 vascular and 4 ERCP cases). Mean FT was 1.3 minutes, mean CD to the patient was 12.98 mGy and the mean DAP was 4.53 Gy/cm2. The longest FT noted was 55 min. The maximum CD was 904 mGy and the maximum DAP was 689 Gy/cm2. Using spearman’s correlation test we found out that there is a significant correlation between FT and DAP (correlation coefficient = 0.615, p. value 0.001). There is a significant correlation between FT and CD (correlation coefficient = 0.628, p. value 0.001). Conclusion: Information about FT that used in each procedure can be used as a tool for patient dose optimization. As we found a significant correlation between DAP as well as CD. Reducing fluoroscopic time (FT) is a radiation protection goal, since it serves the purpose of protection for both the patient and the workers.展开更多
The gamma function is a good approximation to the luminosity function of astrophysical objects, and a truncated gamma distribution would permit a more rigorous analysis. This paper examines the generalized gamma distr...The gamma function is a good approximation to the luminosity function of astrophysical objects, and a truncated gamma distribution would permit a more rigorous analysis. This paper examines the generalized gamma distribution (GG) and then introduces the scale and the new double truncation. The magnitude version of the truncated GG distribution with scale is adopted in order to fit the luminosity function (LF) for galaxies or quasars. The new truncated GG LF is applied to the five bands of SDSS galaxies, to the 2dF QSO Redshift Survey in the range of redshifts between 0.3 and 0.5, and to the COSMOS QSOs in the range of redshifts between 3.7 and 4.7. The average absolute magnitude versus redshifts for SDSS galaxies and QSOs of 2dF was modeled adopting a redshift dependence for the lower and upper absolute magnitude of the new truncated GG LF.展开更多
Internal reformation of low steam methane fuel is highly beneficial for improving the energy efficiency and reducing the system complexity and cost of solid oxide fuel cells(SOFCs).However,anode coking for the Ni-base...Internal reformation of low steam methane fuel is highly beneficial for improving the energy efficiency and reducing the system complexity and cost of solid oxide fuel cells(SOFCs).However,anode coking for the Ni-based anode should be prevented before the technology becomes a reality.A multi-physics fully coupled model is employed to simulate the operations of SOFCs fueled by low steam methane.The multi-physics model produces I-V relations that are in excellent agreement with the experimental results.The multi-physics model and the experimental non-coking current density deduced kinetic carbon activity criterion are used to examine the effect of operating parameters and the anode diffusion barrier layer on the propensity of carbon deposition.The interplays among the fuel utilization ratio,current generation,thickness of the barrier layer and the cell operating voltage are revealed.It is demonstrated that a barrier layer of 400μm thickness is an optimal and safe anode design to achieve high power density and non-coking operations.The anode structure design can be very useful for the development of high efficiency and low cost SOFC technology.展开更多
There is an urgent need for high-quality and high-frequency clock generators for high-energy physics experiments.The transmission data rate exceeds 10 Gbps for a single channel in future readout electronics of silicon...There is an urgent need for high-quality and high-frequency clock generators for high-energy physics experiments.The transmission data rate exceeds 10 Gbps for a single channel in future readout electronics of silicon pixel detectors.Others,such as time measurement detectors,require a high time resolution based on the time-to-digital readout architecture.A phase-locked loop(PLL)is an essential and broadly used circuit in these applications.This study presents an application-specific integrated circuit of a low-jitter,low-power LC-tank that is PLL fabricated using 55-nm CMOS technology.It includes a 3rd-order frequency synthesis loop with a programmable bandwidth,a divide-by-2 pre-scaler,standard low-voltage differential signaling interfaces,and a current mode logic(CML)driver for clock transmissions.All the d-flip-flop dividers and phase-frequency detectors are protected from single-event upsets using the triple modular redundancy technique.The proposed VCO uses low-pass filters to suppress the noise from bias circuits.The tested LC-PLL covers a frequency locking range between 4.74 GHz and 5.92 GHz with two sub-bands.The jitter measurements of the frequency-halved clock(2.56 GHz)are less than 460 fs and 0.8 ps for the random and deterministic jitters,respectively,and a total of 7.5 ps peak-to-peak with a bit error rate of 10^(-12).The random and total jitter values for frequencies of 426 MHz and 20 MHz are less than 1.8 ps and 65 ps,respectively.The LC-PLL consumed 27 mW for the core and 73.8 mW in total.The measured results nearly coincided with the simulations and validated the analyses and tests.展开更多
The theory of gravitational waves in the frame of non-local quantum hydrodynamics (NLQH) is considered. From calculations follow that NLQH equations for “empty” space have the traveling wave solutions belonging in p...The theory of gravitational waves in the frame of non-local quantum hydrodynamics (NLQH) is considered. From calculations follow that NLQH equations for “empty” space have the traveling wave solutions belonging in particular to the soliton class. The possible influence and reaction of the background microwave radiation is taken into account. These results lead to the principal correction of the inflation theory and serve as the explanation for the recent discovery of the universe’s cosmic microwave background anomalies. The simple analytical particular cases and numerical calculations are delivered. Proposal for astronomers—to find in the center domain of the hefty cold spot the smallest hot spot as the origin of the initial burst—Big Bang.展开更多
The theory of the matter movement in a black hole in the frame of non-local quantum hydrodynamics (NLQHD) is considered. The theory corresponds to the limit case when the matter density tends to infinity. From calcula...The theory of the matter movement in a black hole in the frame of non-local quantum hydrodynamics (NLQHD) is considered. The theory corresponds to the limit case when the matter density tends to infinity. From calculations follow that NLQHD equations for the black hole space have the traveling wave solutions. The domain of the solution existence is limited by the event horizon where gravity tends to infinity. The simple analytical particular cases and numerical calculations are delivered.展开更多
We hypothesize that 100% of the energy of our cosmic system is held by a physically real Complex Tension Field (CTF). We are using an old methodology of thinking used by our forefather engineers long before the advent...We hypothesize that 100% of the energy of our cosmic system is held by a physically real Complex Tension Field (CTF). We are using an old methodology of thinking used by our forefather engineers long before the advent of modern scientific thinking. We call it Interaction Process Mapping Epistemology or IPM-E. We apply this IPM-E on to the prevailing Measurable Data Modeling Epistemology or MDM-E. This approach helped us analyze the “Measurement Problem”, recognized during the rise of quantum mechanics (QM), and helped us recover a universal property of all linear waves, that they do not interact, or interfere, with each other. This Non-Interaction of Waves, or the NIW-property, should be obvious through daily observations and through the Huygens-Fresnel diffraction integral and through critical evaluation of contradictory hypotheses we have been assigning to photons through ages. This implicates that the time-frequency Fourier theorem, although mathematically correct, and is used universally in all branches of science;does not map the real physical interaction processes for most optical phenomena. Accordingly, we present the necessary modifications for a few selected phenomena in classical and quantum optics to validate the NIW-property. In the process we find that accepting photons as non-interacting, but diffractively propagating linear wave packets crossing the entire cosmic space, requires CTF as a physical medium. Then we develop logical arguments in support of stable elementary particles as nonlinear but resonant vortex-like undulations of this same CTF. These vortex-like particles impose various secondary potential gradients around themselves giving rise to the four forces we know. Thus, CTF can serve as the cosmic substrate to develop a unified field theory without the need of dark matter and dark energy. In the process, we demonstrate a path to add ontologic thinking on our biologically successful epistemic thinking.展开更多
The paper presents the case that physics is already and effectively unified by the energetic tension field, ether. We identify this integrating power of ether first, by re-defining the action generating parameters of ...The paper presents the case that physics is already and effectively unified by the energetic tension field, ether. We identify this integrating power of ether first, by re-defining the action generating parameters of this energetic tension field as the electric-tension, <img src="Edit_1233fa02-9a1c-416a-8153-196733a12887.png" alt="" />, and the magnetic-resistance, <em>μ</em><sub>0</sub>, while re-deriving the Maxwell’s wave equation in analogy with the mechanically stretched string, where the <img src="Edit_07813a1b-d94f-4e68-a3ed-b3023cd3fb5f.png" alt="" />. Then, replacing <img src="Edit_7d06fa1e-760d-4b80-a503-db81378a3512.png" alt="" /> by <img src="Edit_58f15ef0-2e86-42ae-a899-d0b4741f12d0.png" alt="" /> and <em>m</em><sub>0</sub> by <img src="Edit_f8cb7020-1a27-404a-b146-5c1357e1c5b5.png" alt="" />, one can find that almost all working physics theories are being energized by<img src="Edit_f860fcdd-1dc1-40bf-aaf1-e07b0e4a7524.png" alt="" />and <em>μ</em><sub>0</sub>. To complete the unification, we can now postulate that the particles are also freely propagating EM waves, but they are spatially localized as in-phase, close-looped (IP-CL) vortex-like propagation modes of ether. Because of their IP-CL mode structure, they have space-finite spatial structures and remain spatially stationary in the absence of any spatially influencing potential gradients (forces) in their vicinity. Particles’ <em>harmonic phase</em> driven interactions between quantum particles give birth to the <em>appearance</em> of wave-particle duality. There is no need for the confusing and unnecessary de Broglie’s Pilot Wave. The inertia to spatial motion of IP-CL modes automatically accommodates Newton’s laws of motion. The cosmic universality of Maxwellian wave velocity, and particles as IP-CL modes, jointly accommodate the two key postulates of special relativity without the need for unphysical four-dimensionality. The observable universe is represented only by its diverse oscillatory excited states. The stable and stationary Cosmic Ether keeps holding 100% of its energy all the time. We have proposed a one-way light pulse propagation experiment to directly validate the existence of ether, rather than approaching Michelson’s way of measuring the ether drag. We have identified a good number of examples of working theoretical expressions in terms of <img src="Edit_fd739625-efbd-4edd-9e1e-ba4ab5b7c07f.png" alt="" />and<em> μ</em><sub>0</sub> and presented our critical views in physics thinking, belonging to Classical, Relativity, Quantum and Cosmology Physics.展开更多
Review of arguments in refutation of Dyson’s alleged prohibition against use of device physics as to determining if Gravitons can be determined to exist is followed up by use of a hot Plasma within a Tokamak in a red...Review of arguments in refutation of Dyson’s alleged prohibition against use of device physics as to determining if Gravitons can be determined to exist is followed up by use of a hot Plasma within a Tokamak in a redo of the amplitude of alleged Gravitational waves. This overlaps with gravitons, and we follow up with an analysis of the pertinent form of Gravitons, i.e. do we have massless or massive gravitons. In addition we also obtain GW of amplitude as low as five meters above the Tokamak center such low strain values are extremely close to brane world GW, and strain values in early universe cosmology. This is after our device analysis. Using Grischuk and Sachin (1975) amplitude for the GW generation due to plasma in a toroid, we generalize this result for Tokamak physics. We obtain evidence for strain values up to?in a Tokamak center. These values are an order of magnitude sufficient to allow for possible detection of gravitational waves. The critical breakthrough is in utilizing a burning plasma drift current, which relies upon a thermal contribution to an electric field. Such low strain values are extremely close to brane world GW, and strain values in early universe cosmology. We conclude with statements as to comparing our basic results with those of Yan-Gang Miao, Ying-Jie Zhao as to their generalized HUP which gives support to the suppositions given in our comparison of the character of gravitons which are initially at the start of inflation versus those of our present era, as measured by the Tokamak.展开更多
We use Padmabhan’s “Invitation to Astrophysics” formalism of a scalar field evolution of the early universe, from first principles, to show something which seems counter intuitive. How could, just before inflation,...We use Padmabhan’s “Invitation to Astrophysics” formalism of a scalar field evolution of the early universe, from first principles, to show something which seems counter intuitive. How could, just before inflation, kinetic energy be larger than potential energy in pre-Planckian physics, and what physics mechanism is responsible for the Planckian physics result that Potential energy is far larger than kinetic energy. This document answers that question, as well as provides a mechanism for the dominance of kinetic energy in pre-Planckian space-time, as well as its reversal in the Planckian era of cosmology. The kinetic energy is proportional to , with initial degrees of freedom, and T the initial temperature just before the onset of inflation. Our key assumption is the smallness of curvature, as given in the first equation, which permits adoption of the Potential energy and Kinetic energy formalism used, in the Planckian and pre-Planckian space-time physics. Interpretation of this result, if done correctly, will be able to allow a correct distinguishing of relic gravitational waves, as to avoid the BICEP 2 pickup of galactic dust as a false relic Gravitational wave signal, as well as serve as an investigative template as to if quantum gravity is embedded in a deterministic dissipative system, as cited in the conclusion.展开更多
The truncated version of the two-parameter Sujatha distribution is analysed. In particular, its probability density function and distribution function are obtained. The results are applied to the initial mass function...The truncated version of the two-parameter Sujatha distribution is analysed. In particular, its probability density function and distribution function are obtained. The results are applied to the initial mass function for stars, to the luminosity function for galaxies, to the number of galaxies as a function of the redshift and to the average absolute magnitude of a galaxy as a function of its redshift.展开更多
The Maxwell-Boltzmann (MB) distribution for velocities in ideal gases is usually defined between zero and infinity. A double truncated MB distribution is here introduced and the probability density function, the distr...The Maxwell-Boltzmann (MB) distribution for velocities in ideal gases is usually defined between zero and infinity. A double truncated MB distribution is here introduced and the probability density function, the distribution function, the average value, the rth moment about the origin, the root-mean-square speed and the variance are evaluated. Two applications are presented: 1) a numerical relationship between root-mean-square speed and temperature, and 2) a modification of the formula for the Jeans escape flux of molecules from an atmosphere.展开更多
Two relativistic distributions which generalize the Maxwell Boltzman (MB) distribution are analyzed: the relativistic MB and the Maxwell-Jüttner (MJ) distribution. For the two distributions, we derived in terms o...Two relativistic distributions which generalize the Maxwell Boltzman (MB) distribution are analyzed: the relativistic MB and the Maxwell-Jüttner (MJ) distribution. For the two distributions, we derived in terms of special functions the constant of normalization, the average value, the second moment about the origin, the variance, the mode, the asymptotic behavior, approximate expressions for the average value as function of the temperature and the connected inverted expressions for the temperature as function of the average value. Two astrophysical applications to the synchrotron emission in presence of the magnetic field and the relativistic electrons are presented.展开更多
Static and transient spectroscopic characters of newly synthesized start-like molecules, 1,3,5-tri（10-butyl-3-propenyl-10H-phenothiazine）-benzene （TP3B） and 2,4,6-tri（10-butyl-3-propenyl -10H-phenothiazine）-[1,3...Static and transient spectroscopic characters of newly synthesized start-like molecules, 1,3,5-tri（10-butyl-3-propenyl-10H-phenothiazine）-benzene （TP3B） and 2,4,6-tri（10-butyl-3-propenyl -10H-phenothiazine）-[1,3,5]triazine （TP3T）, are studied using static, picosecond fluorescence and femtosecond transient absorption spectroscopy. The results show that when the benzene group is in the center, a large conjugation system is formed, while a fast electron-transfer process happens when the center group is triazine.展开更多
This study was conducted to examine problems that challenged academic performance of physics students in higher governmental institutions in the case of Arbaminch, Wolayita Sodo, Hawassa and Dilla Universities. Questi...This study was conducted to examine problems that challenged academic performance of physics students in higher governmental institutions in the case of Arbaminch, Wolayita Sodo, Hawassa and Dilla Universities. Questionnaires, interviews and video recordings were used to collect relevant data for the study. Data from questionnaires was compiled and analyzed using a computerized data analysis package known as Statistical Package for Social Science SPSS 17.0. The Pearson chi-square test was used to compute to test association between dependent variable and independent variables and T-test was used to find out how academic performance varied with interest to subject matter. On the other hand, ANOVA test was used to test variation of the academic performance in study sites. Besides, percentages were used for comparison of data analysis. The findings reveal the existence of a significant influence of teachers both in fostering positive or negative attitude to subject (physics) and for their poor academic performance in lower class as well as in higher institutions. On the basis of the findings, the least percentage of students (16%) indicated that their current department was the best choice for them during application for admission. Whereas the highest percentage (84%) of sample class students was enrolled in department of physics without their interest and the academic performance (ESELS result), the highest percentage (70) of students who were admitted to department of physics was below 50%. The p values 0.01 and 0.00, respectively for students who are enrolled in department of physics with best choice and without their interest, are less than alpha level of significance (0.05), which reveals that, there is statistical significance academic performance deference between students in both cases. However, the difference is more significant for those students who are enrolled without their interest. By analysis of Pearson chi-square test summary in respective study sites, the p values 0.01, 0.007, 0.021 and 0.022 respectively are less than the alpha (α) level of significance of 0.05, which reveals that there is strong association between those variables. In the other corner of the ANOVA test analysis indicates that p value 0.01 is less than alpha level of significance 0.05. This reveals variation of academic performance of students between four higher governmental institutions where the study is made.展开更多
Many astrophysical phenomena are modeled by an inverse power law distribution at high values of the random variable but often at low values of the random variable we have a departure from an inverse power law. In orde...Many astrophysical phenomena are modeled by an inverse power law distribution at high values of the random variable but often at low values of the random variable we have a departure from an inverse power law. In order to insert a continuous transition from low to high values of the random variable we analyse the truncated gamma-Pareto distribution in two versions by deriving the most important statistical parameters. The application of the results to the distribution in energy of cosmic rays allows deriving an analytical expression for the average energy, which is 2.6 GeV.展开更多
文摘The challenge in searching for fundamental symmetry violation.Neutrinoless double-beta(0νββ)decay represents one of the most profound tests of fundamental symmetries in nature.This hypothetical nuclear process,in which two neutrons simultaneously decay into two protons with the emission of two electrons but no neutrinos,would demonstrate that lepton number is not conserved and confirm that neutrinos are their own antiparticles(Majorana particles).The observation of 0νββdecay would provide crucial insights into the absolute neutrino mass scale and could illuminate the origin of matter-antimatter asymmetry in the universe.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12350404 and 12174066)the Innovation Program for Quantum Science and Technology(Grant No.2021ZD0302600)+1 种基金the National Key Research and Development Program of China(Grant No.2019YFA0308404)the Science and Technology Commission of Shanghai Municipality(Grant Nos.23JC1400600 and 2019SHZDZX01)。
文摘Moirésystems have emerged as an ideal platform for exploring interaction effects and correlated states.However,most of the experimental systems are based on either triangular or honeycomb lattices.In this study,based on the self-consistent Hartree–Fock calculation,we investigate the phase diagram of the kagomélattice in a recently discovered system with two degenerateΓvalley orbitals and strong spin–orbit coupling.By focusing on the filling factors of 1/2,1/3 and 2/3,we identify various symmetry-breaking states by adjusting the screening length and dielectric constant.At the half filling,we discover that the spin–orbit coupling induces Dzyaloshinskii–Moriya interaction and stabilizes a classical magnetic state with 120°ordering.Additionally,we observe a transition to a ferromagnetic state with out-of-plane ordering.In the case of 1/3 filling,the system is ferromagnetically ordered due to the lattice frustration.Furthermore,for 2/3 filling,the system exhibits a pinned droplet state and a 120°magnetic ordered state at weak and immediate coupling strengths,respectively.For the strong coupling case,when dealing with non-integer filling,the system is always charge ordered with sublattice polarization.Our study serves as a starting point for exploring the effects of correlation in moirékagomésystems.
文摘The statistical parameters of five generalizations of the Lindley distribution, such as the average, variance and moments, are reviewed. A new double truncated Lindley distribution with three parameters is derived. The new distributions are applied to model the initial mass function for stars.
文摘We demonstrate that certain astrophysical distributions can be modelled with the truncated Weibull distribution, which can lead to some insights: in particular, we report the average value, the <em>r</em>th moment, the variance, the median, the mode, the generation of random numbers, and the evaluation of the two parameters with maximum likelihood estimators. The first application of the Weibull distribution is the initial mass function for stars. The magnitude version of the Weibull distribution is applied to the luminosity function for the Sloan Digital Sky Survey (SDSS) galaxies and to the photometric maximum of the 2MASS Redshift Survey (2MRS) galaxies. The truncated Weibull luminosity function allows us to model the average value of the absolute magnitude as a function of the redshift for the 2MRS galaxies.
文摘Purpose: Increasing physician awareness of patient exposure to radiation is an important step towards the reduction of potentially harmful effects of radiation. Published studies demonstrated that providing physicians with feedback regarding their fluoroscopy time leads to a reduction in average fluoroscopy times. The aim of this work was to analyze and publish our medical center data observed during the past year;fluoroscopy time (FT), Dose Area Product (DAP) and cumulative dose (CD) were monitored for radiation protection purposes. Methods: Fluoroscopy time is one of multiple radiation dose indices used in radiation safety auditing. Such auditing is nowadays turning into requirement of patient care safety and quality improvement;as indicated by accreditation bodies both nationally and internationally. All non-cardiac procedures performed outside radiology department by surgeons and interventionists are viewed. FT, DAP and CD are extracted for analysis. Results: a total of 846 cases were studied (643 orthopedic, 99 others, 73 urology, 17 chest, 7 vascular and 4 ERCP cases). Mean FT was 1.3 minutes, mean CD to the patient was 12.98 mGy and the mean DAP was 4.53 Gy/cm2. The longest FT noted was 55 min. The maximum CD was 904 mGy and the maximum DAP was 689 Gy/cm2. Using spearman’s correlation test we found out that there is a significant correlation between FT and DAP (correlation coefficient = 0.615, p. value 0.001). There is a significant correlation between FT and CD (correlation coefficient = 0.628, p. value 0.001). Conclusion: Information about FT that used in each procedure can be used as a tool for patient dose optimization. As we found a significant correlation between DAP as well as CD. Reducing fluoroscopic time (FT) is a radiation protection goal, since it serves the purpose of protection for both the patient and the workers.
文摘The gamma function is a good approximation to the luminosity function of astrophysical objects, and a truncated gamma distribution would permit a more rigorous analysis. This paper examines the generalized gamma distribution (GG) and then introduces the scale and the new double truncation. The magnitude version of the truncated GG distribution with scale is adopted in order to fit the luminosity function (LF) for galaxies or quasars. The new truncated GG LF is applied to the five bands of SDSS galaxies, to the 2dF QSO Redshift Survey in the range of redshifts between 0.3 and 0.5, and to the COSMOS QSOs in the range of redshifts between 3.7 and 4.7. The average absolute magnitude versus redshifts for SDSS galaxies and QSOs of 2dF was modeled adopting a redshift dependence for the lower and upper absolute magnitude of the new truncated GG LF.
基金supported by the National Natural Science Foundation of China (No.11574284 abd No.11774324)the National Basic Research Program of China (No.2012CB215405)Collaborative Innovation Center of Suzhou Nano Science and Technology
文摘Internal reformation of low steam methane fuel is highly beneficial for improving the energy efficiency and reducing the system complexity and cost of solid oxide fuel cells(SOFCs).However,anode coking for the Ni-based anode should be prevented before the technology becomes a reality.A multi-physics fully coupled model is employed to simulate the operations of SOFCs fueled by low steam methane.The multi-physics model produces I-V relations that are in excellent agreement with the experimental results.The multi-physics model and the experimental non-coking current density deduced kinetic carbon activity criterion are used to examine the effect of operating parameters and the anode diffusion barrier layer on the propensity of carbon deposition.The interplays among the fuel utilization ratio,current generation,thickness of the barrier layer and the cell operating voltage are revealed.It is demonstrated that a barrier layer of 400μm thickness is an optimal and safe anode design to achieve high power density and non-coking operations.The anode structure design can be very useful for the development of high efficiency and low cost SOFC technology.
基金supported in part by the National Natural Science Foundation of China(Nos.12005245,12075100,and 11775244)by the Scientific and Technological Innovation Project(No.2020000165)from the Institute of High Energy Physics,Chinese Academy of Sciences+1 种基金partially funded by the Scientific Instrument Development Project of the Chinese Academy of Sciences(No.ZDKYYQ20200007)Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.Y201905).
文摘There is an urgent need for high-quality and high-frequency clock generators for high-energy physics experiments.The transmission data rate exceeds 10 Gbps for a single channel in future readout electronics of silicon pixel detectors.Others,such as time measurement detectors,require a high time resolution based on the time-to-digital readout architecture.A phase-locked loop(PLL)is an essential and broadly used circuit in these applications.This study presents an application-specific integrated circuit of a low-jitter,low-power LC-tank that is PLL fabricated using 55-nm CMOS technology.It includes a 3rd-order frequency synthesis loop with a programmable bandwidth,a divide-by-2 pre-scaler,standard low-voltage differential signaling interfaces,and a current mode logic(CML)driver for clock transmissions.All the d-flip-flop dividers and phase-frequency detectors are protected from single-event upsets using the triple modular redundancy technique.The proposed VCO uses low-pass filters to suppress the noise from bias circuits.The tested LC-PLL covers a frequency locking range between 4.74 GHz and 5.92 GHz with two sub-bands.The jitter measurements of the frequency-halved clock(2.56 GHz)are less than 460 fs and 0.8 ps for the random and deterministic jitters,respectively,and a total of 7.5 ps peak-to-peak with a bit error rate of 10^(-12).The random and total jitter values for frequencies of 426 MHz and 20 MHz are less than 1.8 ps and 65 ps,respectively.The LC-PLL consumed 27 mW for the core and 73.8 mW in total.The measured results nearly coincided with the simulations and validated the analyses and tests.
文摘The theory of gravitational waves in the frame of non-local quantum hydrodynamics (NLQH) is considered. From calculations follow that NLQH equations for “empty” space have the traveling wave solutions belonging in particular to the soliton class. The possible influence and reaction of the background microwave radiation is taken into account. These results lead to the principal correction of the inflation theory and serve as the explanation for the recent discovery of the universe’s cosmic microwave background anomalies. The simple analytical particular cases and numerical calculations are delivered. Proposal for astronomers—to find in the center domain of the hefty cold spot the smallest hot spot as the origin of the initial burst—Big Bang.
文摘The theory of the matter movement in a black hole in the frame of non-local quantum hydrodynamics (NLQHD) is considered. The theory corresponds to the limit case when the matter density tends to infinity. From calculations follow that NLQHD equations for the black hole space have the traveling wave solutions. The domain of the solution existence is limited by the event horizon where gravity tends to infinity. The simple analytical particular cases and numerical calculations are delivered.
文摘We hypothesize that 100% of the energy of our cosmic system is held by a physically real Complex Tension Field (CTF). We are using an old methodology of thinking used by our forefather engineers long before the advent of modern scientific thinking. We call it Interaction Process Mapping Epistemology or IPM-E. We apply this IPM-E on to the prevailing Measurable Data Modeling Epistemology or MDM-E. This approach helped us analyze the “Measurement Problem”, recognized during the rise of quantum mechanics (QM), and helped us recover a universal property of all linear waves, that they do not interact, or interfere, with each other. This Non-Interaction of Waves, or the NIW-property, should be obvious through daily observations and through the Huygens-Fresnel diffraction integral and through critical evaluation of contradictory hypotheses we have been assigning to photons through ages. This implicates that the time-frequency Fourier theorem, although mathematically correct, and is used universally in all branches of science;does not map the real physical interaction processes for most optical phenomena. Accordingly, we present the necessary modifications for a few selected phenomena in classical and quantum optics to validate the NIW-property. In the process we find that accepting photons as non-interacting, but diffractively propagating linear wave packets crossing the entire cosmic space, requires CTF as a physical medium. Then we develop logical arguments in support of stable elementary particles as nonlinear but resonant vortex-like undulations of this same CTF. These vortex-like particles impose various secondary potential gradients around themselves giving rise to the four forces we know. Thus, CTF can serve as the cosmic substrate to develop a unified field theory without the need of dark matter and dark energy. In the process, we demonstrate a path to add ontologic thinking on our biologically successful epistemic thinking.
文摘The paper presents the case that physics is already and effectively unified by the energetic tension field, ether. We identify this integrating power of ether first, by re-defining the action generating parameters of this energetic tension field as the electric-tension, <img src="Edit_1233fa02-9a1c-416a-8153-196733a12887.png" alt="" />, and the magnetic-resistance, <em>μ</em><sub>0</sub>, while re-deriving the Maxwell’s wave equation in analogy with the mechanically stretched string, where the <img src="Edit_07813a1b-d94f-4e68-a3ed-b3023cd3fb5f.png" alt="" />. Then, replacing <img src="Edit_7d06fa1e-760d-4b80-a503-db81378a3512.png" alt="" /> by <img src="Edit_58f15ef0-2e86-42ae-a899-d0b4741f12d0.png" alt="" /> and <em>m</em><sub>0</sub> by <img src="Edit_f8cb7020-1a27-404a-b146-5c1357e1c5b5.png" alt="" />, one can find that almost all working physics theories are being energized by<img src="Edit_f860fcdd-1dc1-40bf-aaf1-e07b0e4a7524.png" alt="" />and <em>μ</em><sub>0</sub>. To complete the unification, we can now postulate that the particles are also freely propagating EM waves, but they are spatially localized as in-phase, close-looped (IP-CL) vortex-like propagation modes of ether. Because of their IP-CL mode structure, they have space-finite spatial structures and remain spatially stationary in the absence of any spatially influencing potential gradients (forces) in their vicinity. Particles’ <em>harmonic phase</em> driven interactions between quantum particles give birth to the <em>appearance</em> of wave-particle duality. There is no need for the confusing and unnecessary de Broglie’s Pilot Wave. The inertia to spatial motion of IP-CL modes automatically accommodates Newton’s laws of motion. The cosmic universality of Maxwellian wave velocity, and particles as IP-CL modes, jointly accommodate the two key postulates of special relativity without the need for unphysical four-dimensionality. The observable universe is represented only by its diverse oscillatory excited states. The stable and stationary Cosmic Ether keeps holding 100% of its energy all the time. We have proposed a one-way light pulse propagation experiment to directly validate the existence of ether, rather than approaching Michelson’s way of measuring the ether drag. We have identified a good number of examples of working theoretical expressions in terms of <img src="Edit_fd739625-efbd-4edd-9e1e-ba4ab5b7c07f.png" alt="" />and<em> μ</em><sub>0</sub> and presented our critical views in physics thinking, belonging to Classical, Relativity, Quantum and Cosmology Physics.
文摘Review of arguments in refutation of Dyson’s alleged prohibition against use of device physics as to determining if Gravitons can be determined to exist is followed up by use of a hot Plasma within a Tokamak in a redo of the amplitude of alleged Gravitational waves. This overlaps with gravitons, and we follow up with an analysis of the pertinent form of Gravitons, i.e. do we have massless or massive gravitons. In addition we also obtain GW of amplitude as low as five meters above the Tokamak center such low strain values are extremely close to brane world GW, and strain values in early universe cosmology. This is after our device analysis. Using Grischuk and Sachin (1975) amplitude for the GW generation due to plasma in a toroid, we generalize this result for Tokamak physics. We obtain evidence for strain values up to?in a Tokamak center. These values are an order of magnitude sufficient to allow for possible detection of gravitational waves. The critical breakthrough is in utilizing a burning plasma drift current, which relies upon a thermal contribution to an electric field. Such low strain values are extremely close to brane world GW, and strain values in early universe cosmology. We conclude with statements as to comparing our basic results with those of Yan-Gang Miao, Ying-Jie Zhao as to their generalized HUP which gives support to the suppositions given in our comparison of the character of gravitons which are initially at the start of inflation versus those of our present era, as measured by the Tokamak.
文摘We use Padmabhan’s “Invitation to Astrophysics” formalism of a scalar field evolution of the early universe, from first principles, to show something which seems counter intuitive. How could, just before inflation, kinetic energy be larger than potential energy in pre-Planckian physics, and what physics mechanism is responsible for the Planckian physics result that Potential energy is far larger than kinetic energy. This document answers that question, as well as provides a mechanism for the dominance of kinetic energy in pre-Planckian space-time, as well as its reversal in the Planckian era of cosmology. The kinetic energy is proportional to , with initial degrees of freedom, and T the initial temperature just before the onset of inflation. Our key assumption is the smallness of curvature, as given in the first equation, which permits adoption of the Potential energy and Kinetic energy formalism used, in the Planckian and pre-Planckian space-time physics. Interpretation of this result, if done correctly, will be able to allow a correct distinguishing of relic gravitational waves, as to avoid the BICEP 2 pickup of galactic dust as a false relic Gravitational wave signal, as well as serve as an investigative template as to if quantum gravity is embedded in a deterministic dissipative system, as cited in the conclusion.
文摘The truncated version of the two-parameter Sujatha distribution is analysed. In particular, its probability density function and distribution function are obtained. The results are applied to the initial mass function for stars, to the luminosity function for galaxies, to the number of galaxies as a function of the redshift and to the average absolute magnitude of a galaxy as a function of its redshift.
文摘The Maxwell-Boltzmann (MB) distribution for velocities in ideal gases is usually defined between zero and infinity. A double truncated MB distribution is here introduced and the probability density function, the distribution function, the average value, the rth moment about the origin, the root-mean-square speed and the variance are evaluated. Two applications are presented: 1) a numerical relationship between root-mean-square speed and temperature, and 2) a modification of the formula for the Jeans escape flux of molecules from an atmosphere.
文摘Two relativistic distributions which generalize the Maxwell Boltzman (MB) distribution are analyzed: the relativistic MB and the Maxwell-Jüttner (MJ) distribution. For the two distributions, we derived in terms of special functions the constant of normalization, the average value, the second moment about the origin, the variance, the mode, the asymptotic behavior, approximate expressions for the average value as function of the temperature and the connected inverted expressions for the temperature as function of the average value. Two astrophysical applications to the synchrotron emission in presence of the magnetic field and the relativistic electrons are presented.
基金Supported by the National Natural Science Foundation of China under grant Nos 60878019, 10934001, 60677002 and 10821062, and the National Basic Research Program of China under Grant Nos 2009CB930504, 2006CB921601 and 2006CB806007.
文摘Static and transient spectroscopic characters of newly synthesized start-like molecules, 1,3,5-tri（10-butyl-3-propenyl-10H-phenothiazine）-benzene （TP3B） and 2,4,6-tri（10-butyl-3-propenyl -10H-phenothiazine）-[1,3,5]triazine （TP3T）, are studied using static, picosecond fluorescence and femtosecond transient absorption spectroscopy. The results show that when the benzene group is in the center, a large conjugation system is formed, while a fast electron-transfer process happens when the center group is triazine.
文摘This study was conducted to examine problems that challenged academic performance of physics students in higher governmental institutions in the case of Arbaminch, Wolayita Sodo, Hawassa and Dilla Universities. Questionnaires, interviews and video recordings were used to collect relevant data for the study. Data from questionnaires was compiled and analyzed using a computerized data analysis package known as Statistical Package for Social Science SPSS 17.0. The Pearson chi-square test was used to compute to test association between dependent variable and independent variables and T-test was used to find out how academic performance varied with interest to subject matter. On the other hand, ANOVA test was used to test variation of the academic performance in study sites. Besides, percentages were used for comparison of data analysis. The findings reveal the existence of a significant influence of teachers both in fostering positive or negative attitude to subject (physics) and for their poor academic performance in lower class as well as in higher institutions. On the basis of the findings, the least percentage of students (16%) indicated that their current department was the best choice for them during application for admission. Whereas the highest percentage (84%) of sample class students was enrolled in department of physics without their interest and the academic performance (ESELS result), the highest percentage (70) of students who were admitted to department of physics was below 50%. The p values 0.01 and 0.00, respectively for students who are enrolled in department of physics with best choice and without their interest, are less than alpha level of significance (0.05), which reveals that, there is statistical significance academic performance deference between students in both cases. However, the difference is more significant for those students who are enrolled without their interest. By analysis of Pearson chi-square test summary in respective study sites, the p values 0.01, 0.007, 0.021 and 0.022 respectively are less than the alpha (α) level of significance of 0.05, which reveals that there is strong association between those variables. In the other corner of the ANOVA test analysis indicates that p value 0.01 is less than alpha level of significance 0.05. This reveals variation of academic performance of students between four higher governmental institutions where the study is made.
文摘Many astrophysical phenomena are modeled by an inverse power law distribution at high values of the random variable but often at low values of the random variable we have a departure from an inverse power law. In order to insert a continuous transition from low to high values of the random variable we analyse the truncated gamma-Pareto distribution in two versions by deriving the most important statistical parameters. The application of the results to the distribution in energy of cosmic rays allows deriving an analytical expression for the average energy, which is 2.6 GeV.
