The managed floating exchange rate system is one of special manifestations of target zone system,and actually it is a quasi-target zone system. Hence RMB equilibrium exchange rate may be estimated by use of the method...The managed floating exchange rate system is one of special manifestations of target zone system,and actually it is a quasi-target zone system. Hence RMB equilibrium exchange rate may be estimated by use of the method of exchange rate target zone model. At present,the sticky-price model is one of best models,and it is a extension of flex-price model. The model is based on assumptions of price inertia and output decided by demand. Under those assumptions and the condition of the commodity and the currency market equilibrium,a stochastic differential equation may be established,and in the light of the equation,we may get a exchange rate function. Our research indicates a good outcome may be made,applying the sticky-price model to estimate RMB equilibrium exchange rate.展开更多
Field experiments to evaluate four different colored sticky cards for trapping non-target insects were conducted in an organic maize field in the Heinigou region of China. Yellow, blue, green, and red sticky cards wer...Field experiments to evaluate four different colored sticky cards for trapping non-target insects were conducted in an organic maize field in the Heinigou region of China. Yellow, blue, green, and red sticky cards were used to trap insects in the field. The total number of insects species caught was 54, with 3,862 individuals recorded. Over half of the specimens caught were non-target insects, including phytophagous insects, particularly dipteran species(including many mosquitoes)(50.3%), followed by target pests(37.0%), and beneficial insects(12.7%). Statistical analysis revealed a significant difference in attraction to target pests, non-target pests, and beneficial insects among treatment groups. The results showed that higher numbers of target pests(Myzus persicae Sulzer, Empoasca flavescens Fabricius, Nysius ericaecshinly Schilling) were caught on yellow sticky card traps compared with blue, green, or red sticky card traps, indicating that yellow was the best trap color for target pests, with green and blue being progressively less attractive. For non-target insects, including phytophagous insects, flies, and mosquitoes,higher numbers of were caught on blue sticky card traps compared with yellow,green, or red sticky card traps. Our study indicated that blue was the most attractive color for flies, especially for the housefly, Musca domestica Linnaeus. Our study also showed that most beneficial insects exhibited preferences to particular trap color characteristics: yellow was the most attractive color for parasitic wasps and lady beetles; blue was the most attractive color for hoverflies and honeybees. In contrast,green and red had no significant attraction to beneficial insects.展开更多
文摘The managed floating exchange rate system is one of special manifestations of target zone system,and actually it is a quasi-target zone system. Hence RMB equilibrium exchange rate may be estimated by use of the method of exchange rate target zone model. At present,the sticky-price model is one of best models,and it is a extension of flex-price model. The model is based on assumptions of price inertia and output decided by demand. Under those assumptions and the condition of the commodity and the currency market equilibrium,a stochastic differential equation may be established,and in the light of the equation,we may get a exchange rate function. Our research indicates a good outcome may be made,applying the sticky-price model to estimate RMB equilibrium exchange rate.
基金Supported by the Misereor Foundation(grant ref:335-031-1028 Z)
文摘Field experiments to evaluate four different colored sticky cards for trapping non-target insects were conducted in an organic maize field in the Heinigou region of China. Yellow, blue, green, and red sticky cards were used to trap insects in the field. The total number of insects species caught was 54, with 3,862 individuals recorded. Over half of the specimens caught were non-target insects, including phytophagous insects, particularly dipteran species(including many mosquitoes)(50.3%), followed by target pests(37.0%), and beneficial insects(12.7%). Statistical analysis revealed a significant difference in attraction to target pests, non-target pests, and beneficial insects among treatment groups. The results showed that higher numbers of target pests(Myzus persicae Sulzer, Empoasca flavescens Fabricius, Nysius ericaecshinly Schilling) were caught on yellow sticky card traps compared with blue, green, or red sticky card traps, indicating that yellow was the best trap color for target pests, with green and blue being progressively less attractive. For non-target insects, including phytophagous insects, flies, and mosquitoes,higher numbers of were caught on blue sticky card traps compared with yellow,green, or red sticky card traps. Our study indicated that blue was the most attractive color for flies, especially for the housefly, Musca domestica Linnaeus. Our study also showed that most beneficial insects exhibited preferences to particular trap color characteristics: yellow was the most attractive color for parasitic wasps and lady beetles; blue was the most attractive color for hoverflies and honeybees. In contrast,green and red had no significant attraction to beneficial insects.
