In order to evaluate the carbonation life of newly-built concrete structures,two kinds of nondestructive methods are adopted to test the thickness of the concrete cover and the ultrasonic velocity of two newly-built t...In order to evaluate the carbonation life of newly-built concrete structures,two kinds of nondestructive methods are adopted to test the thickness of the concrete cover and the ultrasonic velocity of two newly-built tunnel structures.Simultaneously a probabilistic method is proposed based on the relationship between the accelerated carbonation rate and the ultrasonic velocity.This proposed method is applied to evaluate the carbonation related lives of two newly-built tunnels and the results indicate that even under nearly the same environment and CO2 combining conditions,there exits a big difference in the probabilistic carbonation lives between the two tunnels;i.e.,the probabilistic lives of Tunnel A and Tunnel B are 94.0% and 82.3% and the corresponding maximum discrepancies are 11.6% and 27.0%,respectively.Thus,it can be concluded that the scattered quality of the concrete cover is attributed to the differences in construction technique,which eventually leads to the diversity in the evaluated probabilistic carbonation lives of the two tunnels.展开更多
Hydrologic models generally represent the most dominant processes since they are mere simplifications of physical reality and thus are subject to many significant uncertainties. As such, a coupling strategy is propose...Hydrologic models generally represent the most dominant processes since they are mere simplifications of physical reality and thus are subject to many significant uncertainties. As such, a coupling strategy is proposed. To this end, the coupling of the artificial neural network （ANN） with the Xin＇anjiang conceptual model with a view to enhance the quality of its flow forecast is presented. The approach uses the latest observations and residuals in runoff/discharge forecasts from the Xin＇anjiang model. The two complementary models （Xin＇anjiang ＆ ANN） are used in such a way that residuals of the Xin＇anjiang model are forecasted by a neural network model so that flow forecasts can be improved as new observations come in. For the complementary neural network, the input data were presented in a patterned format to conform to the calibration regime of the Xin＇anjiang conceptual model, using differing variants of the neural network scheme. The results show that there is a substantial improvement in the accuracy of the forecasts when the complementary model was operated on top of the Xin＇anjiang conceptual model as compared with the results of the Xin＇anjiang model alone.展开更多
With the persistent efforts of the emerging concepts as well as new types of decoration materials, modem interior design concepts usher in a new round of innovation. Facing the impact of the new innovative ideas, the ...With the persistent efforts of the emerging concepts as well as new types of decoration materials, modem interior design concepts usher in a new round of innovation. Facing the impact of the new innovative ideas, the Chinese traditional culture and art urgently need a way to combine efficient with the modern design concept.展开更多
Modem engineering management activities have all become more complex, being far beyond the economic and technological areas, due to their growing grand scales, increasingly complex structures and integrated systems. T...Modem engineering management activities have all become more complex, being far beyond the economic and technological areas, due to their growing grand scales, increasingly complex structures and integrated systems. Therefore, we need focus our attention on engineering management activities by resorting to dialectical thinking and take full account of them based on the height of the new era. This paper described and analyzed engineering management activities from the following 5 aspects ： the cyclic promotion between engineering management theory and engineering management practice, the in-depth integration of engineering management concepts with engineering management methods, the coordinated harmonization of engineering management system with engineering management details, the mutual promotion between engineering management standardization and engineering management innovation, the common enhancement between engineering management team and engineering management system.展开更多
This paper considers the nonstandard renewal risk model in which a part of surplus is invested into a Black-Scholes market whose price process is modelled by a geometric Brownian motion, claim sizes form a sequence of...This paper considers the nonstandard renewal risk model in which a part of surplus is invested into a Black-Scholes market whose price process is modelled by a geometric Brownian motion, claim sizes form a sequence of not necessarily identically distributed and pairwise quasi-asymptotically independent random variables with dominatedly-varying tails.The authors obtain a weakly asymptotic formula for the finite-time and infinite-time ruin probabilities.In particular,if the claims are identically distributed and consistently-varying tailed,then an asymptotic formula is presented.展开更多
基金Key Construction Project of Nanjing Yangtze River Tunnel(No.7612005822)the National Basic Research Program of China(973Program)(No.2009CB623203).
文摘In order to evaluate the carbonation life of newly-built concrete structures,two kinds of nondestructive methods are adopted to test the thickness of the concrete cover and the ultrasonic velocity of two newly-built tunnel structures.Simultaneously a probabilistic method is proposed based on the relationship between the accelerated carbonation rate and the ultrasonic velocity.This proposed method is applied to evaluate the carbonation related lives of two newly-built tunnels and the results indicate that even under nearly the same environment and CO2 combining conditions,there exits a big difference in the probabilistic carbonation lives between the two tunnels;i.e.,the probabilistic lives of Tunnel A and Tunnel B are 94.0% and 82.3% and the corresponding maximum discrepancies are 11.6% and 27.0%,respectively.Thus,it can be concluded that the scattered quality of the concrete cover is attributed to the differences in construction technique,which eventually leads to the diversity in the evaluated probabilistic carbonation lives of the two tunnels.
文摘Hydrologic models generally represent the most dominant processes since they are mere simplifications of physical reality and thus are subject to many significant uncertainties. As such, a coupling strategy is proposed. To this end, the coupling of the artificial neural network （ANN） with the Xin＇anjiang conceptual model with a view to enhance the quality of its flow forecast is presented. The approach uses the latest observations and residuals in runoff/discharge forecasts from the Xin＇anjiang model. The two complementary models （Xin＇anjiang ＆ ANN） are used in such a way that residuals of the Xin＇anjiang model are forecasted by a neural network model so that flow forecasts can be improved as new observations come in. For the complementary neural network, the input data were presented in a patterned format to conform to the calibration regime of the Xin＇anjiang conceptual model, using differing variants of the neural network scheme. The results show that there is a substantial improvement in the accuracy of the forecasts when the complementary model was operated on top of the Xin＇anjiang conceptual model as compared with the results of the Xin＇anjiang model alone.
文摘With the persistent efforts of the emerging concepts as well as new types of decoration materials, modem interior design concepts usher in a new round of innovation. Facing the impact of the new innovative ideas, the Chinese traditional culture and art urgently need a way to combine efficient with the modern design concept.
基金National Natural Science Foundation of China (No. 71131002No. 71071045+1 种基金No. 70631003)Ph. D. Programs Foundation of Ministry of Education of China (No. 200803590007)
文摘Modem engineering management activities have all become more complex, being far beyond the economic and technological areas, due to their growing grand scales, increasingly complex structures and integrated systems. Therefore, we need focus our attention on engineering management activities by resorting to dialectical thinking and take full account of them based on the height of the new era. This paper described and analyzed engineering management activities from the following 5 aspects ： the cyclic promotion between engineering management theory and engineering management practice, the in-depth integration of engineering management concepts with engineering management methods, the coordinated harmonization of engineering management system with engineering management details, the mutual promotion between engineering management standardization and engineering management innovation, the common enhancement between engineering management team and engineering management system.
基金supported by the National Science Foundation of China under Grant No.11071182the fund of Nanjing University of Information Science and Technology under Grant No.Y627
文摘This paper considers the nonstandard renewal risk model in which a part of surplus is invested into a Black-Scholes market whose price process is modelled by a geometric Brownian motion, claim sizes form a sequence of not necessarily identically distributed and pairwise quasi-asymptotically independent random variables with dominatedly-varying tails.The authors obtain a weakly asymptotic formula for the finite-time and infinite-time ruin probabilities.In particular,if the claims are identically distributed and consistently-varying tailed,then an asymptotic formula is presented.
