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《时间单位》教学设计与评析
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作者 袁瑞禹 李军 《山东教育》 2003年第16期47-49,共3页
关键词 《时间单位》 教学设计 评析 小学 数学
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Composite Time Concept for Quantum Mechanics and Bio-Psychology 被引量:1
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作者 Franz Klaus Jansen 《Journal of Philosophy Study》 2018年第2期49-66,共18页
Time has multiple aspects and is difficult to define as one unique entity, which therefore led to multiple interpretations in physics and philosophy. However, if the perception of time is considered as a composite tim... Time has multiple aspects and is difficult to define as one unique entity, which therefore led to multiple interpretations in physics and philosophy. However, if the perception of time is considered as a composite time concept, it can be decomposed into basic invariable components for the perception of progressive and support-fixed time and into secondary components with possible association to unit-defined time or tense. Progressive time corresponds to Bergson's definition of duration without boundaries, which cannot be divided for measurements. Time periods are already lying in the past and fixed on different kinds of support. The human memory is the first automatic support, but any other support suitable for time registration can also be considered. The true reproduction of original time from any support requires conditions identical to the initial conditions, if not time reproduction becomes artificially modified as can be seen with a film. Time reproduction can be artificially accelerated, slowed down, extended or diminished, and also inverted from the present to the past, which only depends on the manipulation of the support, to which time is firmly linked. Tense associated to progressive and support fixed time is a psychological property directly dependent on an observer, who judges his present as immediate, his past as finished and his future as uncertain. Events can be secondarily associated to the tenses of an observer. Unit-defined time is essential for physics and normal live and is obtained by comparison of support-fixed time to systems with regular motions, like clocks. The association of time perception to time units can also be broken. Einstein's time units became relative, in quantum mechanics, some physicist eliminated time units, others maintained them. Nevertheless, even the complete elimination of time units is not identical to timelessness, since the psychological perception of progressive and support-fixed time still remains and cannot be ignored. It is not seizable by physical methods, but experienced by everybody in everyday life. Contemporary physics can only abandon the association of time units or tenses to the basic components in perceived time. 展开更多
关键词 composite time time perception progressive time time association physical time quantum mechanics bio-psychology
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Chaotic phenomenon and the maximum predictable time scale of observation series of urban hourly water consumption 被引量:2
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作者 柳景青 张士乔 俞申凯 《Journal of Zhejiang University Science》 EI CSCD 2004年第9期1053-1059,共7页
The chaotic characteristics and maximum predictable time scale of the observation series of hourly water consumption in Hangzhou were investigated using the advanced algorithm presented here is based on the convention... The chaotic characteristics and maximum predictable time scale of the observation series of hourly water consumption in Hangzhou were investigated using the advanced algorithm presented here is based on the conventional Wolf's algorithm for the largest Lyapunov exponent. For comparison, the largest Lyapunov exponents of water consumption series with one-hour and 24-hour intervals were calculated respectively. The results indicated that chaotic characteristics obviously exist in the hourly water consumption system; and that observation series with 24-hour interval have longer maximum predictable scale than hourly series. These findings could have significant practical application for better prediction of urban hourly water consumption. 展开更多
关键词 Hourly water consumption series Lyapunov exponent CHAOS Maximum predictable time scale
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Time-frequency characteristics of blasting vibration signals measured in milliseconds 被引量:9
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作者 Zhao Mingsheng ZhangJianhua Yi Changping 《Mining Science and Technology》 EI CAS 2011年第3期349-352,共4页
In order to study the time-frequency characteristics of blasting vibration signals, measured in milliseconds, we carried out site blasting vibration tests at an open pit of the Jinduicheng Mine. Based on recorded fiel... In order to study the time-frequency characteristics of blasting vibration signals, measured in milliseconds, we carried out site blasting vibration tests at an open pit of the Jinduicheng Mine. Based on recorded field data and applying a combination of RSPWVD and wavelet, we analyzed the time-fre- quency characteristics of recorded field data, summarized the time-frequency characteristics of blasting vibration signals in different frequency bands and present detailed information of blasting vibration sig- nals in milliseconds of high time-frequency resolutions. Because RSPWVD can be seen as of definite physical significance to signal energy distribution in time and frequency domains, we studied the energy distribution of blasting vibration signals for various milliseconds intervals from a perspective of energy distribution. The results indicate that the effect of milliseconds intervals on time-frequency characteris- tics of blasting vibration signals is significant; the length of delay time directly affects the energy distri- bution of blasting vibration signals as well as the duration of energy in ffeauencv bands. 展开更多
关键词 Blasting vibrationMillisecond blastingWavelet analysis RSPWVD Time-frequency characteristics
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Specific Power Consumption as Factor Disintegration Process Control of Digging-Wheel Excavators
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作者 Josef Jurman and Jiri Fries 《Journal of Mechanics Engineering and Automation》 2013年第9期591-594,共4页
The determination of digging resistance is of decisive importance when evaluating the mining process of digging-wheel excavators. Methodic of measuring and determinant relations (formulae) are different in various c... The determination of digging resistance is of decisive importance when evaluating the mining process of digging-wheel excavators. Methodic of measuring and determinant relations (formulae) are different in various countries and by the comparison of them, underlying data for complex and objective evaluation using the knowledge from the field of rock disintegration can be obtained. In virtue of analysis of many measurements in situ, rather high specific power consumption with a wheel of excavator has been proved. What was the criterion for evaluation was the power consumption related to the volume of a rock disintegrated per unit time. From theoretical analyses, possibilities of eliminating a negative influence of the human factor upon the mining process and thus possibilities of optimum utilizing the power input of a wheel drive follow. 展开更多
关键词 WHEEL EXCAVATOR energy CONSUMPTION DISINTEGRATION digging.
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Survey of Shopping Streets as Basic Knowledge for Revitalizing the Old Town Centre of Parma
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作者 Andrea Ghiretti Chiara Vernizzi 《Journal of Civil Engineering and Architecture》 2010年第3期46-56,共11页
The revitalization of the historic fabric should not be considered only a matter of safeguarding the cultural heritage of collective memory; it will mainly be to recover and value an urban life, as in the urban contex... The revitalization of the historic fabric should not be considered only a matter of safeguarding the cultural heritage of collective memory; it will mainly be to recover and value an urban life, as in the urban context, the historic centre plays a function of social identification and recognition of the community, that commercial distribution helps to keep alive. It is widely spreading the concept of Old Town as Natural Shopping Centre: with this word, we define commercial complex and not homogenous places, developed over time without programming unit. designed as a unique space, which fall within a certain urban perimeter, work together as a business, financial administration, facilities and service all coordinated by a common policy development. In order to recover the vitality of the consolidated tissue of the city of Parma, the Town Council has started to study its historic centre as Natural Shopping Centre, relying on the potential inherent in the existing commercial streets. 展开更多
关键词 Historical town urban survey. Natural Shopping Centre (NSC) curtains building
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Capacity Analysis for Dynamic Space Networks
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作者 Yang Lu Bo Li +2 位作者 Wenjing Kang Gongliang Liu Xueting Li 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第6期45-49,共5页
To evaluate transmission rate of highly dynamic space networks,a new method for studying space network capacity is proposed in this paper. Using graph theory,network capacity is defined as the maximum amount of flows ... To evaluate transmission rate of highly dynamic space networks,a new method for studying space network capacity is proposed in this paper. Using graph theory,network capacity is defined as the maximum amount of flows ground stations can receive per unit time. Combined with a hybrid constellation model,network capacity is calculated and further analyzed for practical cases. Simulation results show that network capacity will increase to different extents as link capacity,minimum ground elevation constraint and satellite onboard processing capability change. Considering the efficiency and reliability of communication networks,how to scientifically design satellite networks is also discussed. 展开更多
关键词 space network capacity hybrid constellation model graph theory practical cases
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Importance of the Role of Gibberellic Acid and Potassium Nitrate in Seed Germination Habanero
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作者 Oscar Gabriel Villegas-Torres Martha Ldla Dommguez-Patino +3 位作者 Carlos Manuel Acosta-Durfin HectorSotelo-Nava Jose Daniel Lopez-Gomez Guillermo Flores-Sfinchez 《Journal of Chemistry and Chemical Engineering》 2013年第2期145-153,共9页
The habanero chili (Capsicum chinense Jacq.) is a species of great demand in the domestic and international markets. One problem in the cultivation is low percentage of seed germination. There is little information ... The habanero chili (Capsicum chinense Jacq.) is a species of great demand in the domestic and international markets. One problem in the cultivation is low percentage of seed germination. There is little information on the use of promoters and imbibition time to increase this parameter, without compromising the quality of seedlings. In this context, authors assessed the independent effect of GAs (gibberellic acid) and KNOs at concentrations of 0, 100, 200, 300, 400 and 500 mg·L1. Seeds without preconditioning were the witness. The experimental unit was a Petri dish with 50 seeds on filter paper placed equidistant. There were three replicates per treatment and the experimental design was randomized complete block. Imbibition time was 24 h. The experimental units were kept in an incubator at 22 ± 2 ℃. From the time of planting and for periods of 24 h for 14 d, experimental units were reviewed to determine the time at the beginning of germination and the total cumulative percentage. The authors also determined the number of normal and abnormal seedlings, the length of hypocotyl and radicle, weight of fresh and dry matter of seedlings. On the fifth day after sowing in vitro, concentrations of 500 mg·L^-1 of GAs, 300 and 400 mg·L^-1 KNO3, increased 208% the percentage of seed germination of habanero chile. On day 14 after sowing in vitro concentrations of 500 mg·L^-1 GA3, 300 and 400 mg·L^-1 KNO3, increased 23% normal seedlings and 40% dry matter thereof, with respect to seeds obtained without preconditioning. Unconditioned seeds before sowing produced 125% more seedlings. 展开更多
关键词 IMBIBITION HYPOCOTYL RADICLE dry matter fresh matter.
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Unit Root Analysis of Traffic Time Series in Toll Highways
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作者 Antonio Sanchez Solino Antonio L. Lara Galera 《Journal of Civil Engineering and Architecture》 2012年第12期1641-1647,共7页
Concession contracts in highways often include some kind of clauses (for example, a minimum traffic guarantee) that allow for better management of the business risks. The value of these clauses may be important and ... Concession contracts in highways often include some kind of clauses (for example, a minimum traffic guarantee) that allow for better management of the business risks. The value of these clauses may be important and should be added to the total value of the concession. However, in these cases, traditional valuation techniques, like the NPV (net present value) of the project, are insufficient. An alternative methodology for the valuation of highway concession is one based on the real options approach. This methodology is generally built on the assumption of the evolution of traffic volume as a GBM (geometric Brownian motion), which is the hypothesis analyzed in this paper. First, a description of the methodology used for the analysis of the existence of unit roots (i.e., the hypothesis of non-stationarity) is provided. The Dickey-Fuller approach has been used, which is the most common test for this kind of analysis. Then this methodology is applied to perform a statistical analysis of traffic series in Spanish toll highways. For this purpose, data on the AADT (annual average daily traffic) on a set of highways have been used. The period of analysis is around thirty years in most cases. The main outcome of the research is that the hypothesis that traffic volume follows a GBM process in Spanish toll highways cannot be rejected. This result is robust, and therefore it can be used as a starting point for the application of the real options theory to assess toll highway concessions. 展开更多
关键词 Real options unit root analysis INVESTMENT highway concession traffic.
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Learning by Doing Effect in North South Trade under the Global Value Chains: An Empirical Analysis of Various Industries in the U.S.
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作者 Lin Kong 《International Journal of Technology Management》 2013年第12期25-28,共4页
This paper studies the division of labor and economic development under global value chains in North South trade by mainly investigating the changes of production hours and cost per unit along with more and more outpu... This paper studies the division of labor and economic development under global value chains in North South trade by mainly investigating the changes of production hours and cost per unit along with more and more output and increasing trade value in several industries in the U.S., because the U. S. is at the leading position in the division of labor by global value chains. The empirical evidence reveals that more international outsourcing, there will be more detailed division of labor, and the industry unit production time and production cost will show more declining trend year by year. This is consistent with that the global value chains and the outsourcing play more and more important roles in the international division of labor and economic growth in both developed and developing countries, and helps explain the integration of workforce across countries in the global value chains. 展开更多
关键词 Global Value Chains North South Trade Division of Labor Learning by Doing INDUSTRIES
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On the mathematically reliable long-term simulation of chaotic solutions of Lorenz equation in the interval [0,10000] 被引量:5
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作者 LIAO ShiJun WANG PengFei 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第2期330-335,共6页
Using 1200 CPUs of the National Supercomputer TH-A1 and a parallel integral algorithm based on the 3500th-order Taylor expansion and the 4180-digit multiple precision data,we have done a reliable simulation of chaotic... Using 1200 CPUs of the National Supercomputer TH-A1 and a parallel integral algorithm based on the 3500th-order Taylor expansion and the 4180-digit multiple precision data,we have done a reliable simulation of chaotic solution of Lorenz equation in a rather long interval 0 t 10000 LTU(Lorenz time unit).Such a kind of mathematically reliable chaotic simulation has never been reported.It provides us a numerical benchmark for mathematically reliable long-term prediction of chaos.Besides,it also proposes a safe method for mathematically reliable simulations of chaos in a finite but long enough interval.In addition,our very fine simulations suggest that such a kind of mathematically reliable long-term prediction of chaotic solution might have no physical meanings,because the inherent physical micro-level uncertainty due to thermal fluctuation might quickly transfer into macroscopic uncertainty so that trajectories for a long enough time would be essentially uncertain in physics. 展开更多
关键词 CHAOS reliable simulation uncertainty propagation
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Orbit Fitting Based on Helmert Transformation 被引量:2
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作者 王解先 《Geo-Spatial Information Science》 2009年第2期95-99,共5页
Orbit fitting is used in many GPS applications. For example, in Precise Point Positioning (PPP), GPS orbits (SP3 orbits) are normally retrieved either from IGS or from one of its Analysis Centers (ACs) with 15 minutes... Orbit fitting is used in many GPS applications. For example, in Precise Point Positioning (PPP), GPS orbits (SP3 orbits) are normally retrieved either from IGS or from one of its Analysis Centers (ACs) with 15 minutes’ sampling, which is much bigger than the normal observation sampling. Therefore, algorithms should be derived to fit GPS orbits to the observation time. Many methods based on interpolation were developed. Using these methods the orbits fit well at the sampling points. However, these methods ignore the physical motion model of GPS satellites. Therefore, the trajectories may not fit the true orbits at the periods in between 2 sampling epochs. To solve this problem, we develop a dynamic approach, in which a model based on Helmert transformation is developed in GPS orbit fitting. In this orbit fitting approach, GPS orbits at sampling points are treated as pseudo-observations. Thereafter, Helmert transformation is built up between the pseudo-observations and dynamically integrated orbits at each epoch. A set of Helmert parameters together with corrections of GPS initial orbits are then modeled as unknown parameters. Results show that the final fit orbits have the same precision as the IGS final orbits. 展开更多
关键词 precise point positioning(PPP) IGS orbits orbit fitting Helmert transformation
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The discrete logarithm problem from a local duality perspective
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作者 HUANG MingDeh 《Science China Mathematics》 SCIE 2013年第7期1421-1427,共7页
The discrete logarithm problem is analyzed from the perspective of Tate local duality. Local duality in the multiplicative case and the case of Jacobians of curves over p-adic local fields are considered. When the loc... The discrete logarithm problem is analyzed from the perspective of Tate local duality. Local duality in the multiplicative case and the case of Jacobians of curves over p-adic local fields are considered. When the local field contains the necessary roots of unity, the case of curves over local fields is polynomial time reducible to the multiplicative case, and the multiplicative case is polynomial time equivalent to computing discrete logarithm in finite fields. When the local field does not contains the necessary roots of unity, similar results can be obtained at the cost of going to an extension that contains these roots of unity. There was evidence in the analysis that suggests that the minimal extension where the local duality can be rationally and algorithmically defined must contain the roots of unity. Therefore, the discrete logarithm problem appears to be well protected against an attack using local duality. These results are also of independent interest for algorithmic study of arithmetic duality as they explicitly relate local duality in the case of curves over local fields to the multiplicative case and Tate-Lichtenbaum pairing (over finite fields). 展开更多
关键词 discrete logarithm local duality
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