Delineating life circles is an essential prerequisite for urban community life circle planning. Recent studies combined the environmental contexts with residents’ global positioning system(GPS) data to delineate the ...Delineating life circles is an essential prerequisite for urban community life circle planning. Recent studies combined the environmental contexts with residents’ global positioning system(GPS) data to delineate the life circles. This method, however, is constrained by GPS data, and it can only be applied in the GPS surveyed communities. To address this limitation, this study developed a generalizable delineation method without the constraint of behavioral data. According to previous research, the community life circle consists of the walking-accessible range and internal structure. The core task to develop the generalizable method was to estimate the spatiotemporal behavioral demand for each plot of land to acquire the internal structure of the life circle, as the range can be delineated primarily based on environmental data. Therefore, behavioral demand estimation models were established through logistic regression and machine learning techniques, including decision trees and ensemble learning. The model with the lowest error rate was chosen as the final estimation model for each type of land. Finally, we used a community without GPS data as an example to demonstrate the effectiveness of the estimation models and delineation method. This article extends the existing literature by introducing spatiotemporal behavioral demand estimation models, which learn the relationships between environmental contexts, population composition and the existing delineated results based on GPS data to delineate the internal structure of the community life circle without employing behavioral data. Furthermore, the proposed method and delineation results also contributes to facilities adjustments and location selections in life circle planning, people-oriented transformation in urban planning, and activity space estimation of the population in evaluating and improving the urban policies.展开更多
The traditional newsvendor model assumes that a decision-maker is risk-neutral. However, in actuality, a decisionmaker's order behavior is often influenced by waste-averse preference and stockout-averse preference...The traditional newsvendor model assumes that a decision-maker is risk-neutral. However, in actuality, a decisionmaker's order behavior is often influenced by waste-averse preference and stockout-averse preference. We extend the newsvendor model with consideration of averse preferences to investigate how the decision results of the previous period impact the order behavior of the current period, and design an inventory decision-making behavior experiment. Results from the study demonstrate that the order behavior of both a group and an individual exhibits a demand chasing phenomenon, and the former is more significant. Through the interval estimation of the decision maker's order quantity, by the maximum likelihood method we find that the stockout-averse preference has an effect on the decision-making when the prior period is insufficient, causing the current period order quantity larger than the expected profit-maximizing order quantity. In a similar way, waste-averse preference has an effect on decision-making when the prior period is surplus, resulting in the current period order quantity smaller than the expected profit-maximizing order quantity. Finally, we investigate the formation mechanism of demand chasing phenomenon from the perspective of the averse preferences, and propose that this phenomenon is a decision maker's cognitive reaction to stochastic demand environment.展开更多
Consumers and developers are the market transaction subjects which drive the development of building energy efficiency market. High energy prices, unreasonable heating system, information asymmetry of building energy ...Consumers and developers are the market transaction subjects which drive the development of building energy efficiency market. High energy prices, unreasonable heating system, information asymmetry of building energy suppress demand of energy efficiency construction; high technical risk and construction cost, nonstandard market restrict the supply of energy efficiency construction. To promote the development of building energy efficiency, we must set up effective incentive policies for both sides of the market transaction, improve the supervisory system, promote the technological progress, build the information sharing platform, so as to achieve the purpose of cultivating and improving the building energy efficiency market system, regulating the behavior of supply and demand subject, building the mutually beneficial and cooperative partnership, and realizing the balance of interests.展开更多
It is known that structural stiffness and strength distributions have an important role in the seismic response of buildings. The effect of using different code-specified lateral load patterns on the seismic performan...It is known that structural stiffness and strength distributions have an important role in the seismic response of buildings. The effect of using different code-specified lateral load patterns on the seismic performance of fixed-base buildings has been investigated by researchers during the past two decades. However, no investigation has yet been carried out for the case of soil-structure systems. In the present study, through intensive parametric analyses of 21,600 linear and nonlinear MDOF systems and considering five different shear strength and stiffness distribution patterns, including three code-specified patterns as well as uniform and concentric patterns subjected to a group of earthquakes recorded on alluvium and soft soils, the effect of structural characteristics distribution on the strength demand and ductility reduction factor of MDOF fixed-base and soil-structure systems are parametrically investigated. The results of this study show that depending on the level of inelasticity, soil flexibility and number of degrees-of-freedoms (DOFs), structural characteristics distribution can significantly affect the strength demand and ductility reduction factor of MDOF systems. It is also found that at high levels of inelasticity, the ductility reduction factor of low-rise MDOF soil-structure systems could be significantly less than that of fixed-base structures and the reduction is less pronounced as the number of stories increases.展开更多
基金Under the auspices of the National Natural Science Foundation of China(No.41571144)。
文摘Delineating life circles is an essential prerequisite for urban community life circle planning. Recent studies combined the environmental contexts with residents’ global positioning system(GPS) data to delineate the life circles. This method, however, is constrained by GPS data, and it can only be applied in the GPS surveyed communities. To address this limitation, this study developed a generalizable delineation method without the constraint of behavioral data. According to previous research, the community life circle consists of the walking-accessible range and internal structure. The core task to develop the generalizable method was to estimate the spatiotemporal behavioral demand for each plot of land to acquire the internal structure of the life circle, as the range can be delineated primarily based on environmental data. Therefore, behavioral demand estimation models were established through logistic regression and machine learning techniques, including decision trees and ensemble learning. The model with the lowest error rate was chosen as the final estimation model for each type of land. Finally, we used a community without GPS data as an example to demonstrate the effectiveness of the estimation models and delineation method. This article extends the existing literature by introducing spatiotemporal behavioral demand estimation models, which learn the relationships between environmental contexts, population composition and the existing delineated results based on GPS data to delineate the internal structure of the community life circle without employing behavioral data. Furthermore, the proposed method and delineation results also contributes to facilities adjustments and location selections in life circle planning, people-oriented transformation in urban planning, and activity space estimation of the population in evaluating and improving the urban policies.
基金Funded by the Fundamental Research Funds for the Central Universities of China(No.26816WTD23)Key Projects of Scientific Research and Development Plan,Chengdu Railway Bureau,China(No.CX1716)Sichuan Science and Technology Project,China(Title:Safety operation behavior mechanism of rail transit dispatcher taking the Chengdu metro as an example)
文摘The traditional newsvendor model assumes that a decision-maker is risk-neutral. However, in actuality, a decisionmaker's order behavior is often influenced by waste-averse preference and stockout-averse preference. We extend the newsvendor model with consideration of averse preferences to investigate how the decision results of the previous period impact the order behavior of the current period, and design an inventory decision-making behavior experiment. Results from the study demonstrate that the order behavior of both a group and an individual exhibits a demand chasing phenomenon, and the former is more significant. Through the interval estimation of the decision maker's order quantity, by the maximum likelihood method we find that the stockout-averse preference has an effect on the decision-making when the prior period is insufficient, causing the current period order quantity larger than the expected profit-maximizing order quantity. In a similar way, waste-averse preference has an effect on decision-making when the prior period is surplus, resulting in the current period order quantity smaller than the expected profit-maximizing order quantity. Finally, we investigate the formation mechanism of demand chasing phenomenon from the perspective of the averse preferences, and propose that this phenomenon is a decision maker's cognitive reaction to stochastic demand environment.
基金supported by Nature Science Foundation of China (Grant No. 71171141)Soft Science Research Project of MOE (Grant No. 2013-R1-14)Social Science Planning Project in Tianjin City (Grant No. TJGLHQ1403)
文摘Consumers and developers are the market transaction subjects which drive the development of building energy efficiency market. High energy prices, unreasonable heating system, information asymmetry of building energy suppress demand of energy efficiency construction; high technical risk and construction cost, nonstandard market restrict the supply of energy efficiency construction. To promote the development of building energy efficiency, we must set up effective incentive policies for both sides of the market transaction, improve the supervisory system, promote the technological progress, build the information sharing platform, so as to achieve the purpose of cultivating and improving the building energy efficiency market system, regulating the behavior of supply and demand subject, building the mutually beneficial and cooperative partnership, and realizing the balance of interests.
文摘It is known that structural stiffness and strength distributions have an important role in the seismic response of buildings. The effect of using different code-specified lateral load patterns on the seismic performance of fixed-base buildings has been investigated by researchers during the past two decades. However, no investigation has yet been carried out for the case of soil-structure systems. In the present study, through intensive parametric analyses of 21,600 linear and nonlinear MDOF systems and considering five different shear strength and stiffness distribution patterns, including three code-specified patterns as well as uniform and concentric patterns subjected to a group of earthquakes recorded on alluvium and soft soils, the effect of structural characteristics distribution on the strength demand and ductility reduction factor of MDOF fixed-base and soil-structure systems are parametrically investigated. The results of this study show that depending on the level of inelasticity, soil flexibility and number of degrees-of-freedoms (DOFs), structural characteristics distribution can significantly affect the strength demand and ductility reduction factor of MDOF systems. It is also found that at high levels of inelasticity, the ductility reduction factor of low-rise MDOF soil-structure systems could be significantly less than that of fixed-base structures and the reduction is less pronounced as the number of stories increases.
