THE RELATIONSHIP BETWEEN THE SPONTANEOUS NOCTURNALEPISODES OF ALKALINIZATION AND AUTONOMIC NERVOUSFUNCTION ON FD PATIENTS

Spontaneousnocturnalepisodesofalkaliniza-tionduringtheearlymorningareseenin7o%~8o%ofnormalsubjectsandfunctionaldispepsia(FD)patientswhoundergoprolongedambulatoryintragastricpHmonitoring"."-Thedurationsofalkalineshiftsarefromhalfanhourtoseveralhours,thepHelevatesto7andeven8.However,controversyexistsovertheiretiology.Someinves-tigatorshavepostulatedbutnotprovedthatthereasonisadecreaseofvagaIactivitywithasubse-quentdecreaseinacidsecretiontl'3].Heartratevariability(HRV)representsanoninvasivean…     

Where are the dangerous intersections for pedestrians and cyclists: A colocation-based approach

Pedestrians and cyclists are vulnerable road users. They are at greater risk for being killed in a crash than other road users. The percentage of fatal crashes that involve a pedestrian or cyclist is higher than the overall percentage of total trips taken by both modes. Because of this risk, finding ways to minimize problematic street environments is critical. Understanding traffic safety spatial patterns and identifying dangerous locations with significantly high crash risks for pedestrians and cyclists is essential in order to design possible countermeasures to improve road safety. This research develops two indicators for examining spatial correlation patterns between elements of the built environment (intersections) and crashes (pedestrian- or cyclist-involved). The global colocation quotient detects the overall connection in an area while the local colocation quotient identifies the locations of high-risk intersections. To illustrate our approach, we applied the methods to inspect the colocation patterns between pedestrian- or cyclist-vehicle crashes and intersections in Houston, Texas and we identified among many intersections the ones that significantly attract crashes. We also scrutinized those intersections, discussed possible attributes leading to high colocation of crashes, and proposed corresponding countermeasures.     

Uncertainty analysis of extreme mooring loads associated with environmental contours and peak tension distributions

This paper aims to assess the uncertainty on the extreme mooring loads of floating system considering short-term variability. Two environmental contour approaches based on the inverse First and Second Order Reliability Methods are employed to identify critical sea states that may give rise to extreme loads. The uncertainty related to the construction of environmental contours is addressed including significant differences due to marginal distribution fitting, parameter estimation methods and joint models. Three measured datasets are analysed using a known conditional joint distribution and proposed mixed copula model. 3-h time domain numerical simulation for each sea state is conducted and the characteristic extreme responses of mooring lines subjected to design loads are assessed. The uncertainties due to various statistical models including the average conditional exceedance rate method as well as global maxima, peak-over-threshold method combined with Gumbel distribution, Generalized Extreme Value distribution, Generalized Pareto distribution and 3-parameter Weibull distribution are investigated and quantified. It is observed that marginal distributions, joint models and parameters estimation methods have apparent effect on design loads estimation, and the extreme tensions of the semi-submersible platform shows significant difference using various probabilistic models. The results indicate that those epistemic uncertainties should be account for in the reliability analysis or safety factor calibration for mooring systems.     

Propagation and origin of warm anomalies in the Angola Benguela upwelling system in 2001

Warmer than average sea surface temperatures were observed by the Tropical Rainfall Mission Microwave Imager in the Angola Benguela Current system in late austral summer 2001 and persisted for about three months. These coastal anomalies extended offshore by 1 to 4° longitude and were not due to local ocean atmosphere interaction or relaxation of the upwelling favorable southerly winds. Instead, they were remotely forced by ocean atmosphere interaction in the Tropical Atlantic. Satellite remote sensing and a linear ocean model suggest that relaxation of trade winds along the equator triggered Kelvin waves that crossed the basin within a month in early 2001. Westerly wind anomalies were also observed in December 2000 and January 2001 over most of the Tropical Atlantic contributing to a warm preconditioning due to an enhancement of the oceanic annual cycle. This led to abnormal sea level heights near equatorial Africa that propagated southwards along the coast towards the Angola Benguela Frontal zone. This process increased the seasonal penetration of warm and salty water of tropical origin into the Angola Benguela upwelling system.     

依托铁路货场的临港物流园区规划研究——以莆田东站物流园区规划为例

临港物流园区凭借其优越的区位条件及强大的综合交通能力在我国发展迅速。为指导依托铁路货场的临港物流园区规划,以莆田东站物流园区规划为案例,基于MSFLB物流园区规划方法,着重分析影响规划的控制要素,创新规划理念,强化战略定位和发展目标,最终提出打造联运中心、中转枢纽及联动核心的规划构想,并据此对莆田东站物流园区空间布局进行详细设计,为指导此类物流园区规划提供了参考与借鉴。     

ArcGIS空间分析功能在道路交通环境影响后评价中的应用

以ArcGIS空间分析模块为工具，在吸收道路建设环境影响后评价各种常用方法优点的基础上，提出了一种简便实用的评价方法，并给出了评价实例的详细操作步骤。     

Incumbent responses to low-cost airline entry and exit: A spatial autoregressive panel data analysis

While the US airline industry has been substantially transformed in recent years by the growth of low-cost airlines, the cost-saving benefits of lower airfares are difficult to gauge empirically. There are two important ways in which this paper contributes to the existing literature on the impact of the low-cost carriers (LCCs). First, the availability of route-level panel data allows us to examine the role of the LCCs in the long-run adjustment of airfares as well as the responses of the incumbent carriers to LCC entry and exit in a dynamic setting. Second, we capitalize on recent developments in spatial econometrics and explicitly model the spatial dependence among adjacent airline routes, an issue often ignored by previous studies. Although most of the pro-competitive effects of LCC entry take place after entry, we find evidence that the incumbent carriers also cut airfares in anticipation of entry by the LCCs. Moreover fares remain lower even after Southwest Airlines exits. Our empirical analysis confirms the spatial dependence among airfares in adjacent routes, provides estimates of the consumer benefits from lower airfares in routes affected by LCCs, and shows that there are substantial indirect benefits, i.e. lower fares in spatially-linked, nearby routes.     

社区步行通达性对独栋住宅房价的效益评估--美国德克萨斯州奥斯丁市空间特征分析

通过分析美国德克萨斯州奥斯丁市2010—2012年独栋住宅的销售价格,以街道智慧步行指数(Street Smart Walk Score)和人行道密度(Sidewalk Density)作为衡量指标,研究社区步行通达性对房价的影响。使用Cliff-Ord空间特征模型(即广义空间模型,General Spatial Model,或者SAC)控制空间自相关影响。结果表明：在依赖小汽车的社区通过增加设施可达性来提升步行通达性的举措并不能提高房价;增加人行道也只能最小限度地提高房价。投资社区便利设施和人行道对适宜步行社区的房价提升效果比依赖小汽车的社区显著。     

A heuristic model of bounded route choice in urban areas

There is substantial evidence to indicate that route choice in urban areas is complex cognitive process, conducted under uncertainty and formed on partial perspectives. Yet, conventional route choice models continue make simplistic assumptions around the nature of human cognitive ability, memory and preference. In this paper, a novel framework for route choice in urban areas is introduced, aiming to more accurately reflect the uncertain, bounded nature of route choice decision making. Two main advances are introduced. The first involves the definition of a hierarchical model of space representing the relationship between urban features and human cognition, combining findings from both the extensive previous literature on spatial cognition and a large route choice dataset. The second advance involves the development of heuristic rules for route choice decisions, building upon the hierarchical model of urban space. The heuristics describe the process by which quick, ‘good enough’ decisions are made when individuals are faced with uncertainty. This element of the model is once more constructed and parameterised according to findings from prior research and the trends identified within a large routing dataset. The paper outlines the implementation of the framework within a real-world context, validating the results against observed behaviours. Conclusions are offered as to the extension and improvement of this approach, outlining its potential as an alternative to other route choice modelling frameworks.