Based on the cylindrical cavity expansion theory, a plastic-damage-elastic model is proposed for the penetration problem of geo-material. In the model, the unified strength criterion (Yu, 1991) is adopted as the failu...Based on the cylindrical cavity expansion theory, a plastic-damage-elastic model is proposed for the penetration problem of geo-material. In the model, the unified strength criterion (Yu, 1991) is adopted as the failure criterion. The distributions of the radial stress and velocity are analyzed. According to the Newton's second law, a series results of the final penetration depth and the impedance load are obtained to different parameter b, when a rigid projectile normally impacts and penetrates a semi-infinite geo-material target with an impact velocity of 300-1200 m/s. By comparing with the test data available, it appears that the method can be used in analyzing the final depth and the impedance load of a rigid projectile penetrating into a semi-infinite target with different impact velocities.展开更多
A research on the topic was conducted at the Experimental Station of Agriculture--Khan Krum during the period 2009-2011. The dynamics of growth and thickening of the cultivars Independence, Nectagrand 2, Aureliogrand,...A research on the topic was conducted at the Experimental Station of Agriculture--Khan Krum during the period 2009-2011. The dynamics of growth and thickening of the cultivars Independence, Nectagrand 2, Aureliogrand, Fantasy, Kassiopeia and Caldessi 2000 grafted on seedling rootstock （Elbert） and clonal GF-677 have been studied in the second year of nursery. The aim of the study was to investigate the growth characteristics of the introduced cultivars of nectarines grafted on traditional seedling rootstock （Elbert） and GF-677. At the beginning of the vegetation period of the seed cultivar rootstock （Elbert） has strong growth and thickening of the stem. The dynamics of growth and thickening of the stem depend on the used rootstock and cultivar. The obtained planting material corresponds to the existing quality standards.展开更多
The development of HKCMM standards is one of the achievements of developing Hong Kong into an intemational centre for Chinese medicine. In order to enable more people concerned to have an intimate knowledge of this st...The development of HKCMM standards is one of the achievements of developing Hong Kong into an intemational centre for Chinese medicine. In order to enable more people concerned to have an intimate knowledge of this standard, the author was invited to introduce the development of HKCMM standards to readers, including： 1） the history of the project and the basis for legislative supports; 2） the composition and operation of the regulatory division, the research institution and the evaluation committee; 3） the progress of HKCMM standards; 4） the contents and features of HKCMM standards.展开更多
文摘Based on the cylindrical cavity expansion theory, a plastic-damage-elastic model is proposed for the penetration problem of geo-material. In the model, the unified strength criterion (Yu, 1991) is adopted as the failure criterion. The distributions of the radial stress and velocity are analyzed. According to the Newton's second law, a series results of the final penetration depth and the impedance load are obtained to different parameter b, when a rigid projectile normally impacts and penetrates a semi-infinite geo-material target with an impact velocity of 300-1200 m/s. By comparing with the test data available, it appears that the method can be used in analyzing the final depth and the impedance load of a rigid projectile penetrating into a semi-infinite target with different impact velocities.
文摘A research on the topic was conducted at the Experimental Station of Agriculture--Khan Krum during the period 2009-2011. The dynamics of growth and thickening of the cultivars Independence, Nectagrand 2, Aureliogrand, Fantasy, Kassiopeia and Caldessi 2000 grafted on seedling rootstock （Elbert） and clonal GF-677 have been studied in the second year of nursery. The aim of the study was to investigate the growth characteristics of the introduced cultivars of nectarines grafted on traditional seedling rootstock （Elbert） and GF-677. At the beginning of the vegetation period of the seed cultivar rootstock （Elbert） has strong growth and thickening of the stem. The dynamics of growth and thickening of the stem depend on the used rootstock and cultivar. The obtained planting material corresponds to the existing quality standards.
文摘The development of HKCMM standards is one of the achievements of developing Hong Kong into an intemational centre for Chinese medicine. In order to enable more people concerned to have an intimate knowledge of this standard, the author was invited to introduce the development of HKCMM standards to readers, including： 1） the history of the project and the basis for legislative supports; 2） the composition and operation of the regulatory division, the research institution and the evaluation committee; 3） the progress of HKCMM standards; 4） the contents and features of HKCMM standards.
