Dynamic Response Characteristic of Building Structure under Blasting Vibration of underneath Tunnel

The vibration induced by blasting excavation of the subway tunnel in complex urban environments may cause harmful effects on adjacent buildings. Investigating the dynamic response of adjacent buildings is a key issue to predict and control blasting hazards. In this paper, the blasting excavation of the subway tunnel right below a building was selected as a case study, and the blast vibrations in the field were monitored. The Hilbert–Huang Transform (HHT) model was used to extract and analyze the time-frequency characteristic parameters of blasting dynamic response signals. By substituting intrinsic mode functions (IMF) component frequency and instantaneous energy for main frequency and blasting total input energy, respectively, the characteristics of time-instantaneous frequency-instantaneous energy of buildings under blasting seismic load were analyzed, and the concept of effective duration of vibration was proposed.

A comprehensive non-uniformity correction method for EMCCD

The non-uniformity of image directly affects the application of EMCCD in various disciplines. The proposed method can significantly improve the uniformity of EMCCD output image. The correction algorithm of "reverse split and forward recovery" is determined through analyzing the imaging model of EMCCD, and the comprehensive non-uniformity correction function model is established. The 8-tap EMCCD chip CCD220 of British e2v company is used for experimental verification. The results show that after the comprehensive correction the consistencies of the light response characteristic curve and the multiplication gain curve of each channel in EMCCD are obviously improved, and also the photo response non-uniformity (PRNU) of the output image is substantially reduced from 24.5 to 4.1%, which prove the effectiveness of the proposed method.

Ecology of the Possum (Trichosurus Vulpecula Kerr) in the Karori Water Supply Reserve, Wellington, Sounds Ecological District

<p>The abundance and condition of possums in various areas of the Karori Reserve, Wellington - Sounds Ecological District was assessed. Possums were most abundant in the upper part of the reserve in an area dominated by bishop and radiata pines with an undergrowth of native species and in an area dominated by gorse and flax shrublands. In the lower part of the reserve, possums were less abundant and there a number of characteristics were observed: possums had a higher body weight for age, their reproductive output was higher and the population was marked by a higher proportion of females and juveniles. This was interpreted as a "compensatory response" characteristic of possum populations maintained at low densities. Possum stomachs were sampled in spring and their contents analysed in order to investigate the importance of Fuchsia excorticata and other plant species to possum diet. In the lower part of the reserve the leaves of Fuchsia excorticata and the flowers of Cytisus scoparius made up more than 50 percent of the possums' forage. In the upper part of the reserve exotic species such as the flowers of Cytisus scoparius and Ulex europeans as well as the leaves of native species such as Aristotelia serrata, Pseudopanax arboreus and Coprosma robusta made up the bulk of possum forage. Exotic plants accounted for a significant proportion of the spring possum diet in the reserve. Whereas most leaves originated from native plants, the exotic species contributed mainly carbohydrate-rich flowers and pollen. The canopy condition of two possum-susceptible tree species Fuchsia excorticata and Pseudopanax arboreus was assessed early in autumn over the years 1993, 1995 and 1996. Over these years, 47 percent of marked fuchsia trees were completely defoliated and most trees are unlikely to recover even if possums are eradicated from the reserve. All defoliated fuchsia trees were located in the upper part of the reserve. On the other hand, 37 percent of marked fuchsia trees exhibited only a little possum damage. Most of these trees were located in the lower part of the reserve where possum density was lower. Increasing possum densities could therefore be correlated with an increasing level of possum damage to fuchsia canopies. Even though Pseudopanax arboreus leaves and petioles were encountered in 10 percent of possum stomachs, the canopies leaves and petioles were encountered in 10 percent of possum stomachs, the canopies of assessed trees did not seem to be greatly affected. It appeared that due to the high abundance of this plant species in the reserve the effects of possum browse were spread over the whole reserve to levels which could be tolerated by an individual Pseudopanax arboreus tree.</p>

Ecology of the Possum (Trichosurus Vulpecula Kerr) in the Karori Water Supply Reserve, Wellington, Sounds Ecological District

<p>The abundance and condition of possums in various areas of the Karori Reserve, Wellington - Sounds Ecological District was assessed. Possums were most abundant in the upper part of the reserve in an area dominated by bishop and radiata pines with an undergrowth of native species and in an area dominated by gorse and flax shrublands. In the lower part of the reserve, possums were less abundant and there a number of characteristics were observed: possums had a higher body weight for age, their reproductive output was higher and the population was marked by a higher proportion of females and juveniles. This was interpreted as a "compensatory response" characteristic of possum populations maintained at low densities. Possum stomachs were sampled in spring and their contents analysed in order to investigate the importance of Fuchsia excorticata and other plant species to possum diet. In the lower part of the reserve the leaves of Fuchsia excorticata and the flowers of Cytisus scoparius made up more than 50 percent of the possums' forage. In the upper part of the reserve exotic species such as the flowers of Cytisus scoparius and Ulex europeans as well as the leaves of native species such as Aristotelia serrata, Pseudopanax arboreus and Coprosma robusta made up the bulk of possum forage. Exotic plants accounted for a significant proportion of the spring possum diet in the reserve. Whereas most leaves originated from native plants, the exotic species contributed mainly carbohydrate-rich flowers and pollen. The canopy condition of two possum-susceptible tree species Fuchsia excorticata and Pseudopanax arboreus was assessed early in autumn over the years 1993, 1995 and 1996. Over these years, 47 percent of marked fuchsia trees were completely defoliated and most trees are unlikely to recover even if possums are eradicated from the reserve. All defoliated fuchsia trees were located in the upper part of the reserve. On the other hand, 37 percent of marked fuchsia trees exhibited only a little possum damage. Most of these trees were located in the lower part of the reserve where possum density was lower. Increasing possum densities could therefore be correlated with an increasing level of possum damage to fuchsia canopies. Even though Pseudopanax arboreus leaves and petioles were encountered in 10 percent of possum stomachs, the canopies leaves and petioles were encountered in 10 percent of possum stomachs, the canopies of assessed trees did not seem to be greatly affected. It appeared that due to the high abundance of this plant species in the reserve the effects of possum browse were spread over the whole reserve to levels which could be tolerated by an individual Pseudopanax arboreus tree.</p>