Microstructure evolution of Ti14 （α＋Ti2Cu） alloy during semi-solid isothermal process at different temperatures was investigated. The results reveal that both the temperature and holding time have effect on the gr...Microstructure evolution of Ti14 （α＋Ti2Cu） alloy during semi-solid isothermal process at different temperatures was investigated. The results reveal that both the temperature and holding time have effect on the grain growth behavior. The grains grow obviously and the degree of globularity increases with the increase of holding time. According to the statistic analysis of experimental data, the grain growth indices are 0.88 and 0.97 at 1 000 ℃ and 1 050 ℃, respectively, which indicates that increasing isothermal temperature would accelerate microstructural evolution.展开更多
The techniques to forecast available parking space(APS) are indispensable components for parking guidance systems(PGS). According to the data collected in Newcastle upon Tyne, England, the changing characteristics of ...The techniques to forecast available parking space(APS) are indispensable components for parking guidance systems(PGS). According to the data collected in Newcastle upon Tyne, England, the changing characteristics of APS were studied. Thereafter, aiming to build up a multi-step APS forecasting model that provides richer information than a conventional one-step model, the largest Lyapunov exponents(largest LEs) method was introduced into PGS. By experimental tests conducted using the same dataset, its prediction performance was compared with traditional wavelet neural network(WNN) method in both one-step and multi-step processes. Based on the results, a new multi-step forecasting model called WNN-LE method was proposed, where WNN, which enjoys a more accurate performance along with a better learning ability in short-term forecasting, was applied in the early forecast steps while the Lyapunov exponent prediction method in the latter steps precisely reflect the chaotic feature in latter forecast period. The MSE of APS forecasting for one hour time period can be reduced from 83.1 to 27.1(in a parking building with 492 berths) by using largest LEs method instead of WNN and further reduced to 19.0 by conducted the new method.展开更多
Planting date is a critical component of soybean [Glycine max （L.） Merr.] production, under dry land conditions in the Southeastern Coastal Plain. The objectives of this study were to 1. Evaluate the effect of plant...Planting date is a critical component of soybean [Glycine max （L.） Merr.] production, under dry land conditions in the Southeastern Coastal Plain. The objectives of this study were to 1. Evaluate the effect of planting date on plant leaf area index （LAI） and normalized difference vegetation index （NDVI） at 60 and 90 days after planting （DAP）, plant height and grain yield, and 2. Determine the optimum planting period by integrating the responses from vegetation growth to yield for soybean maturity group （MG） IV-VIII under dry land conditions in the Southeastern Coastal Plain. Planting dates were scheduled about 14-days intervals from late April to mid-July （2008） or late July （2009）. Greatest grain yield for MG IV was obtained from planting in around mid-May in both years. The yield was greater for MG V planted in May and greater for MG VI-VIII planted in late April and May, but started to decline for planting in early June. Plant LAI and NDVI at 60 DAP were affected by both planting date and precipitation, but were poorly correlated with grain yield. However, plant LAI and NDVI were well correlated with yield and were greater for May planting dates at 90 DAP. These indiccs declined for soybean planted after May. Mature plant height decreased more rapidly with delayed planting. These results indicate that plant growth and yield decreased after May planting. Optimum planting period for all MGs was early to mid-May.展开更多
In the preceding paper （Commun. Theor. Phys. 51 （2009） 321） we have recommended a convenient method for disentangling exponential operators. In this work we use this method for disentangling exponential operators ...In the preceding paper （Commun. Theor. Phys. 51 （2009） 321） we have recommended a convenient method for disentangling exponential operators. In this work we use this method for disentangling exponential operators composed of angular momentum operators. We mainly desentangle the form of exp[2hJz ＋ g J＋ ＋ kJ_] as the ordering exp（... J＋）exp（... Jz）exp（... J_）, we employ the Schwinger Bose realization J_ = bta, J＋ = atb, Jz=（ata - btb）/2 to fulfil this task, without appealing to Lie algebra method. Note that this operator＇s desentanglng is different from its decomposition in normal ordering.展开更多
The circadian rhythms of apical meristem mitosis cells of the two types of soybean were investigated： wild soybeans - Glycine max （L.） Merr. （G. hispida Max.）, G. soja Sieb., and Zucc （G, ussuriensis Reg. and Ma...The circadian rhythms of apical meristem mitosis cells of the two types of soybean were investigated： wild soybeans - Glycine max （L.） Merr. （G. hispida Max.）, G. soja Sieb., and Zucc （G, ussuriensis Reg. and Maack）; and the hybrids of their homozygous forms （F6）. Representatives of the initial kinds and interspecific hybrids for reproduction were grown up in comparable conditions. Seeds of a soybean were grown up at 24℃ in Petri cups in thermostat in darkness during winter. For research of mitotic meristem cages activity the tips of roots were fixed temporal by acetoalcohol （fractional fixing） from 1 p.m. till 12 a.m., further up to 12 p.m. each 60 minutes. Acetokarmin was used for preparing the coloring. For researching of mitotic indexes, there have been analyzed from 6 up to 10 thousand cells at each stage （during each moment of time： 01 hour, 02, 03 06 ... 12, 13 ... 18 hours and further）. Within a day （day ＋ night） in cells of root apical meristem, three mitosis ＂waves＂ in each of the investigated forms with an absolute starting point of rest at 12 p.m., with precisely expressed further periodicity were found out. Each of the investigated forms misses in character of wave processes, on a degree of increase and recession of mitosis waves, on the level of mitotic indexes. Maximal mitotic activity at all the investigated forms is noted at 6 and 12 a.m. and 6 p.m.展开更多
This paper is on a distribution question of Ⅰ type in the combinatorics (see: 'Ke Zhao, Wei WanDi, combinatorial theory, science press, 1981. '). Suppose n distrinct balls, m distinct boxes. The capacity set...This paper is on a distribution question of Ⅰ type in the combinatorics (see: 'Ke Zhao, Wei WanDi, combinatorial theory, science press, 1981. '). Suppose n distrinct balls, m distinct boxes. The capacity set of every box is Now,place the n balls into the m boxes. Thenumber of distinct placed ways is expressed by , and simply by And it is called the distribution number.Main result is:Theorem The exponential generating function of sequence isThus .there is the recurrence relationhere (integer set).展开更多
基金Projects (2005CCA06400, 2007CB613807) supported by the National Basic Research Program of China Project (CHD2010JC115) supported by the Special Fund for Basic Scientific Research of Central Colleges,China
文摘Microstructure evolution of Ti14 （α＋Ti2Cu） alloy during semi-solid isothermal process at different temperatures was investigated. The results reveal that both the temperature and holding time have effect on the grain growth behavior. The grains grow obviously and the degree of globularity increases with the increase of holding time. According to the statistic analysis of experimental data, the grain growth indices are 0.88 and 0.97 at 1 000 ℃ and 1 050 ℃, respectively, which indicates that increasing isothermal temperature would accelerate microstructural evolution.
基金Project(2012CB725402)supported by the National Key Basic Research Program of ChinaProjects(51338003,50908051)supported by the National Natural Science Foundation of China
文摘The techniques to forecast available parking space(APS) are indispensable components for parking guidance systems(PGS). According to the data collected in Newcastle upon Tyne, England, the changing characteristics of APS were studied. Thereafter, aiming to build up a multi-step APS forecasting model that provides richer information than a conventional one-step model, the largest Lyapunov exponents(largest LEs) method was introduced into PGS. By experimental tests conducted using the same dataset, its prediction performance was compared with traditional wavelet neural network(WNN) method in both one-step and multi-step processes. Based on the results, a new multi-step forecasting model called WNN-LE method was proposed, where WNN, which enjoys a more accurate performance along with a better learning ability in short-term forecasting, was applied in the early forecast steps while the Lyapunov exponent prediction method in the latter steps precisely reflect the chaotic feature in latter forecast period. The MSE of APS forecasting for one hour time period can be reduced from 83.1 to 27.1(in a parking building with 492 berths) by using largest LEs method instead of WNN and further reduced to 19.0 by conducted the new method.
文摘Planting date is a critical component of soybean [Glycine max （L.） Merr.] production, under dry land conditions in the Southeastern Coastal Plain. The objectives of this study were to 1. Evaluate the effect of planting date on plant leaf area index （LAI） and normalized difference vegetation index （NDVI） at 60 and 90 days after planting （DAP）, plant height and grain yield, and 2. Determine the optimum planting period by integrating the responses from vegetation growth to yield for soybean maturity group （MG） IV-VIII under dry land conditions in the Southeastern Coastal Plain. Planting dates were scheduled about 14-days intervals from late April to mid-July （2008） or late July （2009）. Greatest grain yield for MG IV was obtained from planting in around mid-May in both years. The yield was greater for MG V planted in May and greater for MG VI-VIII planted in late April and May, but started to decline for planting in early June. Plant LAI and NDVI at 60 DAP were affected by both planting date and precipitation, but were poorly correlated with grain yield. However, plant LAI and NDVI were well correlated with yield and were greater for May planting dates at 90 DAP. These indiccs declined for soybean planted after May. Mature plant height decreased more rapidly with delayed planting. These results indicate that plant growth and yield decreased after May planting. Optimum planting period for all MGs was early to mid-May.
基金Supported by the Natural Science Foundation of Heze University of Shandong Province,China under Grant No.XY07WL01the University Experimental Technology Foundation of Shandong Province under Grant No.S04W138
文摘In the preceding paper （Commun. Theor. Phys. 51 （2009） 321） we have recommended a convenient method for disentangling exponential operators. In this work we use this method for disentangling exponential operators composed of angular momentum operators. We mainly desentangle the form of exp[2hJz ＋ g J＋ ＋ kJ_] as the ordering exp（... J＋）exp（... Jz）exp（... J_）, we employ the Schwinger Bose realization J_ = bta, J＋ = atb, Jz=（ata - btb）/2 to fulfil this task, without appealing to Lie algebra method. Note that this operator＇s desentanglng is different from its decomposition in normal ordering.
文摘The circadian rhythms of apical meristem mitosis cells of the two types of soybean were investigated： wild soybeans - Glycine max （L.） Merr. （G. hispida Max.）, G. soja Sieb., and Zucc （G, ussuriensis Reg. and Maack）; and the hybrids of their homozygous forms （F6）. Representatives of the initial kinds and interspecific hybrids for reproduction were grown up in comparable conditions. Seeds of a soybean were grown up at 24℃ in Petri cups in thermostat in darkness during winter. For research of mitotic meristem cages activity the tips of roots were fixed temporal by acetoalcohol （fractional fixing） from 1 p.m. till 12 a.m., further up to 12 p.m. each 60 minutes. Acetokarmin was used for preparing the coloring. For researching of mitotic indexes, there have been analyzed from 6 up to 10 thousand cells at each stage （during each moment of time： 01 hour, 02, 03 06 ... 12, 13 ... 18 hours and further）. Within a day （day ＋ night） in cells of root apical meristem, three mitosis ＂waves＂ in each of the investigated forms with an absolute starting point of rest at 12 p.m., with precisely expressed further periodicity were found out. Each of the investigated forms misses in character of wave processes, on a degree of increase and recession of mitosis waves, on the level of mitotic indexes. Maximal mitotic activity at all the investigated forms is noted at 6 and 12 a.m. and 6 p.m.
文摘This paper is on a distribution question of Ⅰ type in the combinatorics (see: 'Ke Zhao, Wei WanDi, combinatorial theory, science press, 1981. '). Suppose n distrinct balls, m distinct boxes. The capacity set of every box is Now,place the n balls into the m boxes. Thenumber of distinct placed ways is expressed by , and simply by And it is called the distribution number.Main result is:Theorem The exponential generating function of sequence isThus .there is the recurrence relationhere (integer set).
