An algorithmic approach to continuous location

Bibliography: pages 126-130.We survey the p-median problem and the p-centre problem. Then we investigate two new techniques for continuous optimal partitioning of a tree T with n - 1 edges, where a nonnegative rational valued weight is associated with each edge. The continuous Max-Min tree partition problem (the continuous Min-Max tree partition problem) is to cut the edges in p - 1 places, so as to maximize (respectively minimize) the weight of the lightest (respectively heaviest) resulting subtree. Thus the tree is partitioned into approximately equal components. For each optimization problem, an inefficient implementation of the algorithm is given, which runs in pseudo-polynomial time, using a previously developed algorithm and a construction. We then derive from it a much faster algorithm using a top-down greedy technique, which runs in polynomial time. The algorithms have a variety of applications among others to highway and pipeline maintenance

Observations of Stabilized Turf Shoulders

The improvement of highway shoulders, from the standpoint of appearance and practical value, has been and is at present of considerable interest to all highway departments. A great deal of effort has been expended in the past to develop grass combinations which not only will prevent natural erosion of the surface materials but also impart a pleasing appearance to shoulders and slopes. Attempts to include factors of practical value, such as safe support of traffic loads, have greatly magnified the problem. Numerous types of paved shoulders have been introduced which are quite satisfactory with respect to load bearing but are expensive to construct and often do not equal in appearance the more attractive turf shoulders. Stabilized turf shoulders have been adopted by several state and federal agencies in an attempt to combine aesthetic qualities with those of a practical nature. These shoulders are made principally of granular material but contain sufficient soil to support vegetation, and generally they are covered with a thin layer of topsoil to provide a seed bed. Limited data available indicate that these efforts have been rather successful. The first study of stabilized turf shoulders in Kentucky was initiated during the 1954 construction season when the Division of Design designated an experimental section to be used for this purpose. This site was located on a 6 mile reconstruction project on U.S. 31-W and U.S. 68 from Bowling Green, to the intersection of the two routes at a point approximately 7 miles northward, Project No. I 16 (2) and 113 (5), see Fig. 1. The Division of Research was requested to observe and report on construction procedures and the effectiveness of turf shoulders constructed in this area. The roadway located in this section consists of two traffic lanes in each direction, separated by a depressed median strip 2.0 feet wide. The median strip was constructed in the conventional manner and only the outside shoulders were stabilized. Three different means of stabilization were used, including hardstands at selected intervals with conventional earth shoulders in between

The Economic Impact of Failing Infrastructure in the New York Metropolitan Area

Infrastructure in the New York Metropolitan Area has been seriously underfunded due to a failure of public investment on the local, state and federal level. Prior research has presented concrete reasoning that the now crumbling infrastructure will seriously affect economic growth and worker productivity. This research seeks to quantify the economic effects as a result of this failing infrastructure. My research asks: what are the concrete, additional economic expenditures, due to failing infrastructure, that drivers spend each year? How much do these economic costs decrease our economic productivity, and how do the economic costs compare with proposed infrastructure improvements? From the research, it is evident drivers in the New York-Newark NY-NJ Metropolitan Statistical Area experience some of the highest of these costs than other areas in the Combined Statistical Area. It is projected the 2018 economic cost to these drivers will be $2,045 based on the value of one’s time lost spend in traffic. With a continued lack of investment, these costs are expected to grow due to continued infrastructure failure and a growing population. Various programs have been proposed to alleviate specific bottlenecks in the region, but a coordinated source of investment from local, state and federal levels remains a major issue in securing funding for these projects

Transit proximity effects : Capital MetroRail and its impact on land prices in Austin, Texas

textSince its first operation in 2010, the 32-mile Austin Capital MetroRail has connected downtown Austin to the city of Leander with 9 stations operating in total. Currently, no research has investigated the impact of the Austin MetroRail on property values. This study fills the research gap by understanding its impacts on property values and other socio-economical influences. Hedonic models have been constructed to assess the effects of transit proximity on land price in this research. The model suggests Austin MetroRail has a positive impact on property values- for properties in the study area, every 100 feet further away from the train station, property values will decrease $13,068/acre. Another analysis of the rail only focused on 7 stations located in the city of Austin and suggests transit premium varies by different neighborhood. In high-income neighborhoods, transit proximity impact is positive; and in middle or low- income neighborhoods, it is negative. When stations were grouped into different study areas, models reveal transit proximity has different effects throughout the system. The research findings confirm the positive effect of Austin MetroRail although in some neighborhoods the effects vary and suggest a series of value-capture strategies to help finance future development.Community and Regional Plannin

Modelling beyond Regression Functions: an Application of Multimodal Regression to Speed-Flow Data

An enormous amount of publications deals with smoothing in the sense of nonparametric regression. However, nearly all of the literature treats the case where predictors and response are related in the form of a function y=m(x)+noise. In many situations this simple functional model does not capture adequately the essential relation between predictor and response. We show by means of speed-flow diagrams, that a more general setting may be required, allowing for multifunctions instead of only functions. It turns out that in this case the conditional modes are more appropriate for the estimation of the underlying relation than the commonly used mean or the median. Estimation is achieved using a conditional mean-shift procedure, which is adapted to the present situation