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Advancements in Time Modeling: Relationalism, Divisional Structures, and Geometry
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作者 Steven D. P. Moore 《Journal of Applied Mathematics and Physics》 2024年第10期3358-3383,共26页
This article broadens terminology and approaches that continue to advance time modelling within a relationalist framework. Time is modeled as a single dimension, flowing continuously through independent privileged poi... This article broadens terminology and approaches that continue to advance time modelling within a relationalist framework. Time is modeled as a single dimension, flowing continuously through independent privileged points. Introduced as absolute point-time, abstract continuous time is a backdrop for concrete relational-based time that is finite and discrete, bound to the limits of a real-world system. We discuss how discrete signals at a point are used to temporally anchor zero-temporal points [t = 0] in linear time. Object-oriented temporal line elements, flanked by temporal point elements, have a proportional geometric identity quantifiable by a standard unit system and can be mapped on a natural number line. Durations, line elements, are divisible into ordered unit ratio elements using ancient timekeeping formulas. The divisional structure provides temporal classes for rotational (Rt24t) and orbital (Rt18) sample periods, as well as a more general temporal class (Rt12) applicable to either sample or frame periods. We introduce notation for additive cyclic counts of sample periods, including divisional units, for calendar-like formatting. For system modeling, unit structures with dihedral symmetry, group order, and numerical order are shown to be applicable to Euclidean modelling. We introduce new functions for bijective and non-bijective mapping, modular arithmetic for cyclic-based time counts, and a novel formula relating to a subgroup of Pythagorean triples, preserving dihedral n-polygon symmetries. This article presents a new approach to model time in a relationalistic framework. 展开更多
关键词 relationALISM Mohist Geometry Euclidean Geometry relational-time Discrete-time CONTINUOUS-time Planck time Zero-time
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Quantitative structure retention relationship studies for predicting relative retention times of chlorinated phenols on gas chromatography
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作者 LiSY SunC 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第3期418-422,共5页
A new method of quantitative structure retention relationship(QSRR) studies was reported for predicting gas chromatography(GC) relative retention times(RRTs) of chlorinated phenols (CPs) using a DB 5 column. Chemica... A new method of quantitative structure retention relationship(QSRR) studies was reported for predicting gas chromatography(GC) relative retention times(RRTs) of chlorinated phenols (CPs) using a DB 5 column. Chemical descriptors were calculated from the molecular structure of CPs and related to their gas chromatographic RRTs by using multiple linear regression analysis. The proposed model had a multiple square correlation coefficient R 2=0.970, standard error SE =0.0472, and significant level P =0.0000. The QSRR model also reveals that the gas chromatographic relative retention times of CPs are associated with physicochemical property interactions with the stationary phase,and influenced by the number of chlorine and oxygen in the CP melecules. 展开更多
关键词 QSRR relative retention times molecular descriptors chlorinated phenols
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Biliary tract injury caused by different relative warm ischemia time in liver transplantation in rats 被引量:24
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作者 Zhao, Hong-Feng Zhang, Guo-Wei +3 位作者 Zhou, Jie Lin, Jian-Hua Cui, Zhong-Lin Li, Xiang-Hong 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2009年第3期247-254,共8页
BACKGROUND: There is a controversy over the degree of liver and biliary injury caused by the period of secondary warm ischemia. A liver autotransplantation model was adopted because it excludes the effects of infectio... BACKGROUND: There is a controversy over the degree of liver and biliary injury caused by the period of secondary warm ischemia. A liver autotransplantation model was adopted because it excludes the effects of infection and immunological rejection on bile duct injury. This study was undertaken to assess biliary tract injury caused by relative warm ischemia (secondary warm ischemia time in the biliary tract) and reperfusion. METHODS: One hundred and two rats were randomly divided into 5 groups: group I (control); groups 11 to V, relative warm ischemia times of 0 minute, 30 minutes, I hour and 2 hours. In addition to the levels of serum alkaline phosphatase, and total bilirubin, pathomorphology assessment and TUNEL assay were performed to evaluate biliary tract damage. RESULTS: Under the conditions that there were no significant differences in warm ischemia time, cold perfusion time and anhepatic phase, group comparisons showed statistically significant differences. The least injury occurred in group H (portal vein and hepatic artery reperfused simultaneously) but the most severe injury occurred in group V (biliary tract relative warm ischemia time 2 hours). CONCLUSIONS: Relative warm ischemia is one of the factors that result in bile duct injury, and the relationship between relative warm ischemia time the bile injury degree is time-dependent. Simultaneous arterial and portal reperfusion is the best choice to avoid the bile duct injury caused by relative warm ischemia. (Hepatobiliary Pancreat Dis Int 2009; 8: 247-254) 展开更多
关键词 liver transplantation bile duct ischemia-reperfusion injury relative warm ischemia time models animal RAT
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A QSRR Study on the Relative Retention Time of Halogenated Methyl-phenyl Ethers 被引量:5
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作者 XU Hui-Ying YU Qing-Sen +3 位作者 ZOU Jian-Wei WANG Yan-Hua WANG Hong-Qing CHEN Xue-Song 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第7期811-817,共7页
Halogenated methyl-phenyl ethers (anisoles) are ubiquitous organic compounds in the environment. In the present study, geometrical optimization and electrostatic potential calculations have been performed for 42 hal... Halogenated methyl-phenyl ethers (anisoles) are ubiquitous organic compounds in the environment. In the present study, geometrical optimization and electrostatic potential calculations have been performed for 42 halogenated anisoles at the HF/6-31 G^* level. A number of statistically based parameters have been obtained. By multiple regression method, linear relationships between the gas-chromatographic relative retention time (RRT) and structural descriptors have been established for the training set of 32 halogenated anisoles. The result showed that the parameters derived from electrostatic potentials (ESPs) together with the molecular volume (Vmc) could be well used to express the quantitative structure-RRT relationships of halogenated anisoles. The best two-variable regression model gives a correlation coefficient of 0.980 and a standard deviation of 0.07, and the leave-one-out cross-validated correlation coefficient is 0.975. The goodness of the model has been further validated through exploring the predictive power for the testing set of 10 halogenated anisoles. 展开更多
关键词 halogenated methyl-phenyl ethers (anisoles) molecular electrostatic potentials (ESPs) relative retention time (RRT) QSRR
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Time Related Influence of α-Mercapto-β-(2-Furyl) Acrylic Acid (MFA) in Cadmium Toxicity 被引量:1
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作者 SHASHI KHANDELWAL SUSHIL K.TANDON 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1991年第3期304-309,共6页
The effect of a-mercapto-β-(2-furyl) acrylic acid (MFA, 200 mg/kg, oral) administered 30 min or 24 h post cadmium (1 mg/kg, i.p.) exposure on cadmium toxicity, was investigated in rats. The Cd induced hepatic metallo... The effect of a-mercapto-β-(2-furyl) acrylic acid (MFA, 200 mg/kg, oral) administered 30 min or 24 h post cadmium (1 mg/kg, i.p.) exposure on cadmium toxicity, was investigated in rats. The Cd induced hepatic metallothionein was reduced by MFA treatment parallel to the depletion of hepatic Cd. However, in renal tissue,MFA caused only redistribution of metal from the paniculate to the soluble fraction. Hepatic and renal Zn and renal Cu were significantly increased on Cd exposure. MFA therapy, however, lowered the hepatic Zn and increased the renal Cu levels. The action of MFA appears to be via metal chelation rather than by MT induction. 展开更多
关键词 MFA Acrylic Acid in Cadmium Toxicity Mercapto FURYL time Related Influence of
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Joint DOA and time delay estimation method for space-time coherent distributed signals based on search 被引量:1
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作者 Qian Bin Yang Wanlin Wan Qun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期341-346,共6页
Under dense urban fading environment, performance of joint multi-path parameter estimation method based on traditional point signal model degrades seriously. In this paper, a new space and time signal model based on m... Under dense urban fading environment, performance of joint multi-path parameter estimation method based on traditional point signal model degrades seriously. In this paper, a new space and time signal model based on multipath distribution function is given after new space and time manifold is reconstructed. Then joint spacetime signal subspace is obtained by converting acquired channel from time domain to frequency domain .Then space and time spectrum is formulated by the space sub-matrix and time sub-matrix taken out of joint space-time signal subspace, and parameters are estimated by searching the minimum eigenvalues of the space matrix and the time matrix. Lastly, A space and time parameters matching process is performed by using the orthogonal property between joint noise subspace and the space-time manifold. In contrast with tradition MUSIC, the algorithm we present here only need two 1- dimension searching and was not sensitive to different distribution function. 展开更多
关键词 Space-time coherent distribution DOA Relative time delay Minimum eigenvalue.
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Predicting the Relative Retention Time (RRT) of Polybrominated Diphenyl Ethers (PBDEs) 被引量:2
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作者 Shu Shen LIU Yan LIU +1 位作者 Da Qiang YIN Lian Sheng WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第11期1559-1562,共4页
Using the molecular electronegativity distance vector descriptors derived directly from the molecular topological structures, the relative retention time (RRT) of polybrominated diphenyl ethers (PBDEs) were predic... Using the molecular electronegativity distance vector descriptors derived directly from the molecular topological structures, the relative retention time (RRT) of polybrominated diphenyl ethers (PBDEs) were predicted. A four-variable regression model (M30) with the correlation coefficient of 0.9816 and the root mean square errors of 0.061 was developed using a training set including 30 PBDEs. The correlation coefficient of 0.9841 and the root mean square errors of 0.054 between the values of RRT predicted by M30 and the RRT observed for 16 external PBDEs show a good predictive potential of M30. The descriptors included in the M30 represent four interactions between four pairs of atom types, i.e., atom -C= and -C=, -C= and 〉C=, 〉C= and 〉C=, -C= and -Br. 展开更多
关键词 Polybrominated diphenyl ethers (PBDEs) relative retention time (RRT) molecular electronegativity distance vector (MEDV).
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A Novel Method for Real-Time Monitoring of Channel Siltation Based on Bistatic Scattering Theory
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作者 侯朋 许文海 +1 位作者 王俊生 李瑛 《China Ocean Engineering》 SCIE EI 2010年第1期105-115,共11页
Monitoring the thickness changes of channel siltation is paramount in safeguarding navigation and guiding dredging, This paper presents a novel method for realizing the field monitoring of channel siltation in real ti... Monitoring the thickness changes of channel siltation is paramount in safeguarding navigation and guiding dredging, This paper presents a novel method for realizing the field monitoring of channel siltation in real time. The method is based on the bistatic scattering theory and concerned more with the receiving and processing of multipath signal at high-frequency and small grazing angle. By use of the multipath propagation structure of underwater acoustic channel, the method obtains the silt thickness by calculating the relative time delay of acoustic signals between the direct and the shortest bottom reflected paths. Bistatic transducer pairs are employed to transmit and receive the acoustic signals, and the GPS time synchronization technology is introduced to synchronize the transmitter and receiver, The WRELAX (Weighted Fourier transforul and RELAX) algorithm is used to obtain the high resolution estimation of muhipath time delay. To examine the feasibility of the presented method and the accuracy and precision of the developed system, a series of sea trials are conducted in the southwest coast area of Dalian City, north of the Yellow Sea. The experimental results are compared with that using high-resolution dual echo sounder HydroBoxTM, and the uncertainty is smaller than + 0.06 m. Compared with the existing means for measuring the silt thickness, the present method is innovative, and the system is stable, efficient and provides a better real-time performance. It especially suits monitoring the narrow channel with rapid changes of siltation. 展开更多
关键词 channel siltation real-time monitoring bistatic bottom scattering relative time delay WREIAX multipath signal
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Relative Time Quantum-based Enhancements in Round Robin Scheduling
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作者 Sardar Zafar Iqbal Hina Gull +5 位作者 Saqib Saeed Madeeha Saqib Mohammed Alqahtani Yasser A.Bamarouf Gomathi Krishna May Issa Aldossary 《Computer Systems Science & Engineering》 SCIE EI 2022年第5期461-477,共17页
Modern human life is heavily dependent on computing systems and one of the core components affecting the performance of these systems is underlying operating system.Operating systems need to be upgraded to match the n... Modern human life is heavily dependent on computing systems and one of the core components affecting the performance of these systems is underlying operating system.Operating systems need to be upgraded to match the needs of modern-day systems relying on Internet of Things,Fog computing and Mobile based applications.The scheduling algorithm of the operating system dictates that how the resources will be allocated to the processes and the Round Robin algorithm(RR)has been widely used for it.The intent of this study is to ameliorate RR scheduling algorithm to optimize task scheduling.We have carried out an experimental study where we have developed four variations of RR,each algorithm considers three-time quanta and the performance of these variations was compared with the RR algorithm,and results highlighted that these variations performed better than conventional RR algorithm.In the future,we intend to develop an automated scheduler that can determine optimal algorithm based on the current set of processes and will allocate time quantum to the processes intelligently at the run time.This way the task performance of modern-day systems can be improved to make them more efficient. 展开更多
关键词 CPU scheduling Round Robin enhanced Round Robin relative time quantum operating systems
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Relation between the Intervals ΔE and Δt Obtained in the De-Excitation Process of Electrons in Metals
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作者 Stanislaw Olszewski 《Journal of Modern Physics》 2012年第3期217-220,共4页
A relation between the intervals of energy and time, derived in a former paper and associated with the electron transitions on the Fermi surface of a metal, is examined in comparison with the experimental data. These ... A relation between the intervals of energy and time, derived in a former paper and associated with the electron transitions on the Fermi surface of a metal, is examined in comparison with the experimental data. These data are obtained from the de-excitation process of electrons in metals. A comparison between theory and experiment demonstrated that the new relation between energy and time is fitted much better for the experimental results than the well-known relation due to the Heisenberg theory. 展开更多
关键词 De-Excitation of Electrons METALS relations between the Intervals of Energy and time
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Relative timing jitter compression in a Fabry-Pérot cavity-assisted free-running dual-comb interferometry
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作者 Chen Liu Liang Xu +2 位作者 Lei Zhang Chi Zhang Xinliang Zhang 《Advanced Photonics Nexus》 2024年第5期140-150,共11页
Dual-comb interferometric systems with high time accuracy have been realized for various applications.The flourishing ultralow noise dual-comb system promotes the measurement and characterization of relative timing ji... Dual-comb interferometric systems with high time accuracy have been realized for various applications.The flourishing ultralow noise dual-comb system promotes the measurement and characterization of relative timing jitter,thus improving time accuracy.With optical solutions,introducing an optical reference enables 105 harmonics measurements,thereby breaking the limit set by electrical methods;nonlinear processes or spectral interference schemes were also employed to track the relative timing jitter.However,such approaches operating in the time domain either require additional continuous references or impose stringent requirements on the amount of timing jitter.We propose a scheme to correct the relative timing jitter of a free-running dual-comb interferometry assisted by a Fabry-Pérot(F-P)cavity in the frequency domain.With high wavelength thermal stability provided by the F-P cavity,the absolute wavelength deviation in the operating bandwidth is compressed to<0.4 pm,corresponding to a subpicosecond sensitivity of pulse-to-pulse relative timing jitter.Also,Allan deviation of 10^(-10) is obtained under multiple coherent averaging,which lays the foundation for mode-resolved molecular spectroscopic applications.The spectral absorption features of hydrogen cyanide gas molecules at ambient temperature were measured and matched to the HITRAN database.Our scheme promises to provide new ideas on sensitive measurements of relative timing jitter. 展开更多
关键词 optical frequency comb dual-comb interferometry relative timing jitter postcalibration precision optical metrology
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关系论教学时间观:生成论教学哲学的立场 被引量:1
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作者 曾瑶 张广君 《中国电化教育》 CSSCI 北大核心 2023年第6期33-42,共10页
建立在实体论基础上的教学时间观以测量、控制和管理时间为特征。当代教学时间形态与关系变革发展带来教学时间观变革的契机,表现出“例外状态”与接纳偶然性、全时空交互体验、碎片化与碎片整合、“泛在”时空等新发展。生成论教学哲学... 建立在实体论基础上的教学时间观以测量、控制和管理时间为特征。当代教学时间形态与关系变革发展带来教学时间观变革的契机,表现出“例外状态”与接纳偶然性、全时空交互体验、碎片化与碎片整合、“泛在”时空等新发展。生成论教学哲学(GTP)“关系论”取向的教学时间观亦即关系论教学时间观,是基于时间的关系本体论和关系思维,主要由“时域”“时序”“时机”“时势”“时限”“时效”等一系列教学时间意识和日常性、文化性、历史性、审美性及生命性教学时间等诸种类型观念组成的多维一体教学时间观。关系论教学时间观在反思和重释当代教学时间理论和实践中的时间与人关系问题,滋养和支撑当代教学历史观,理解和运用中国古代“时”的教育潜能思想,倡导和实践时间、生命与文化一体同构的教学等方面,有着深刻的教学哲学意蕴。 展开更多
关键词 教学时间 关系论教学时间观 生成论教学哲学
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New Modes for the Prediction of Gas Chromatographic Relative Retention Times of Polybrominated Diphenyl Ethers
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作者 易忠胜 李连臣 +1 位作者 张爱茜 王连生 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2011年第11期2495-2504,共10页
A series of quantitative structure-retention relationship models were developed to predict gas chromatographic relative retention times (GC-RRTs) for 209 polybrominated diphenyl ether (PBDE) congeners on 10 statio... A series of quantitative structure-retention relationship models were developed to predict gas chromatographic relative retention times (GC-RRTs) for 209 polybrominated diphenyl ether (PBDE) congeners on 10 stationary phases. A genetic algorithm with twofold leave-multiple-out cross validation (LMOCV) was used to select optimal subsets from large-size molecular descriptors. Overall multiple-linear regression fitting correlation coefficients (R2) are greater than 0.988, except for the CP-Sil 19 colunm, in which Q^uocv (correlation coefficient of LMOCV), Q^oocv (correlation coefficient of leave-one-out cross validation, LOOCV), and Rp2re (correlation coefficients of prediction set) are larger than 0.98. The excellent statistical parameters reveal that the models are robust and have high internal and external predictive capability. According to the descriptors for constructing the models, the GC-RRTs in various stationary phases are highly dependent on distances among atoms, branches of molecules, and molecular properties. PBDE congeners with 1, 9, and 10 bromines are major outliers based on the results of the application domain. 展开更多
关键词 gas chromatography relative retention times polybrominated diphenyl ethers leave-multiple-out cross validation quantitative structure-retention relationships genetic algorithm
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罗维利的物理关系论思想
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作者 朱科夫 陈磊 马永革 《自然辩证法研究》 CSSCI 北大核心 2016年第8期90-95,共6页
在西方思想史上,时空关系论和时空实体论的争论不仅影响着古今众多哲学家,更对物理学领域的发展起着引导性的作用。通过考察和分析关系论的代表人物——当代物理学家卡尔罗·罗维利对物理关系论的评述,本文从广义相对论、量子力学... 在西方思想史上,时空关系论和时空实体论的争论不仅影响着古今众多哲学家,更对物理学领域的发展起着引导性的作用。通过考察和分析关系论的代表人物——当代物理学家卡尔罗·罗维利对物理关系论的评述,本文从广义相对论、量子力学和量子引力理论的不同角度探讨了在当代物理前沿基础理论视角下的关系论的内涵和意义。 展开更多
关键词 时空关系论 广义相对论 量子力学诠释 量子引力
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Pulsatile blood flow through stenosed artery with axial translation
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作者 Mukesh Kumar Sharma P. R. Sharma Vinay Nasha 《International Journal of Biomathematics》 2015年第3期1-21,共21页
The study of pulsatile blood flow through axisymmetric stenosed artery subject to an axial translation has been attempted with hematocrit concentration-dependent blood viscosity. The heart contraction and subsequent r... The study of pulsatile blood flow through axisymmetric stenosed artery subject to an axial translation has been attempted with hematocrit concentration-dependent blood viscosity. The heart contraction and subsequent relaxation generate periodic pressure gradient in blood flow and translation in the artery can be represented by Fourier series. Numerical data required for computing Fourier harmonics for the pressure gradient and acceleration in the artery has been simulated from pressure waveform graph and biplanar angiogram. Velocity field has been obtained by solving governing equation using variational Ritz method. The hemodynamic indicators WSS, AWSS, OSI, RRT are derived and computed numerically. The effects of thickness of stenosis, and hematocrit concentration index on these indicators are computed and analyzed through graphs. 展开更多
关键词 STENOSIS HEMATOCRIT PULSATILE WSS oscillatory shear index relative residence time
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