A new inequality on the minimum eigenvalue for the Fan product of nonsingular M-matrices is given. In addition, a new inequality on the spectral radius of the Hadamard product of nonnegative matrices is also obtained....A new inequality on the minimum eigenvalue for the Fan product of nonsingular M-matrices is given. In addition, a new inequality on the spectral radius of the Hadamard product of nonnegative matrices is also obtained. These inequalities can improve considerably some previous results.展开更多
Ecological structure and fruit production of African fan palm stands in Benin were studied on the basis of surveys laid out in ten (10) populations located in three ecological zones. Dendrometric and fruit production ...Ecological structure and fruit production of African fan palm stands in Benin were studied on the basis of surveys laid out in ten (10) populations located in three ecological zones. Dendrometric and fruit production parameters such as: diameter at breast height (dbh), total height (TH), number of fruit bunch per tree, number of fruits per tree, number of seeds per fruit, fruit length and width were measured on all African fan palm trees within thirteen (13) plots of 1,000 m2. Diameter and height classes distribution of the palms in each ecological zone adjusted to Weibull distribution showed a bell shaped curve with left dissymmetry, characteristic of young stands (form coefficient between 1 and 3.6). African fan palm stem number was 156 trees/ha. Variation of dbh, TH, number of fruit bunch per tree were highly significant between populations and ecological zones (P < 0.05%). Trees from Sudanian zone were highly grown (mean dbh = 52.2 cm) while those of Sudano - Guinean transition zone were less (mean dbh = 32.73 cm) and dominated by female trees. African fan palm stands of Pahou is suitable for seed collection for in situ conservation of the species while those of Ouorghi and Akomiah could provide fruits for edible hypocotyls production.展开更多
文摘A new inequality on the minimum eigenvalue for the Fan product of nonsingular M-matrices is given. In addition, a new inequality on the spectral radius of the Hadamard product of nonnegative matrices is also obtained. These inequalities can improve considerably some previous results.
文摘Ecological structure and fruit production of African fan palm stands in Benin were studied on the basis of surveys laid out in ten (10) populations located in three ecological zones. Dendrometric and fruit production parameters such as: diameter at breast height (dbh), total height (TH), number of fruit bunch per tree, number of fruits per tree, number of seeds per fruit, fruit length and width were measured on all African fan palm trees within thirteen (13) plots of 1,000 m2. Diameter and height classes distribution of the palms in each ecological zone adjusted to Weibull distribution showed a bell shaped curve with left dissymmetry, characteristic of young stands (form coefficient between 1 and 3.6). African fan palm stem number was 156 trees/ha. Variation of dbh, TH, number of fruit bunch per tree were highly significant between populations and ecological zones (P < 0.05%). Trees from Sudanian zone were highly grown (mean dbh = 52.2 cm) while those of Sudano - Guinean transition zone were less (mean dbh = 32.73 cm) and dominated by female trees. African fan palm stands of Pahou is suitable for seed collection for in situ conservation of the species while those of Ouorghi and Akomiah could provide fruits for edible hypocotyls production.
基金Supported by the Science Foundation of Fujian Educational Department (JA03159) the Science ResearchFoundation of Putian University(2004Q003 2004Q002)
