Optimization Rules in DLV for the Bridge Crossing Problem

Disjunctive logic programming is a powerful tool in knowledge representation and commonsense reasoning. The first solid implementation of a DLP system is called DLV (Datalog with Vel). In this paper we offer three strategies to produce optimal solutions in DLV for the well-known Bridge Crossing Problem. These strategies are a piggyback strategy, a non-piggyback strategy, and a mixed strategy. An analysis to determine the number of time steps required for an optimal solution using these strategies is provided. We also characterize and prove the conditions under which a particular strategy should be used to obtain an optimal solution. These strategies are implemented in the form of optimization rules in a DLV program for the bridge crossing problem. Preliminary results indicate a drastic reduction in execution time when compared to other DLV programs for bridge crossing which do not incorporate these strategies. Our implementation uses a DLV Java wrapper, allowing us to embed disjunctive logic programs inside an object-oriented environment

Dynamic analysis of road vehicle-bridge systems under turbulent wind by means of Finite Element Models

When an automobile passes over a bridge dynamic effects are produced in vehicle and structure. In addition, the bridge itself moves when exposed to the wind inducing dynamic effects on the vehicle that have to be considered. The main objective of this work is to understand the influence of the different parameters concerning the vehicle, the bridge, the road roughness or the wind in the comfort and safety of the vehicles when crossing bridges. Non linear finite element models are used for structures and multibody dynamic models are employed for vehicles. The interaction between the vehicle and the bridge is considered by contact methods. Road roughness is described by the power spectral density (PSD) proposed by the ISO 8608. To consider that the profiles under right and left wheels are different but not independent, the hypotheses of homogeneity and isotropy are assumed. To generate the wind velocity history along the road the Sandia method is employed. The global problem is solved by means of the finite element method. First the methodology for modelling the interaction is verified in a benchmark. Following, the case of a vehicle running along a rigid road and subjected to the action of the turbulent wind is analyzed and the road roughness is incorporated in a following step. Finally the flexibility of the bridge is added to the model by making the vehicle run over the structure. The application of this methodology will allow to understand the influence of the different parameters in the comfort and safety of road vehicles crossing wind exposed bridges. Those results will help to recommend measures to make the traffic over bridges more reliable without affecting the structural integrity of the viaduc

The capacity-C torch problem

The torch problem (also known as the bridge problem or the flashlight problem) is about getting a number of people across a bridge as quickly as possible under certain constraints. Although a very simply stated problem, the solution is surprisingly non-trivial. The case in which there are just four people and the capacity of the bridge is two is a well-known puzzle, widely publicised on the internet. We consider the general problem where the number of people, their individual crossing times and the capacity of the bridge are all input parameters. We present two methods to determine the shortest total crossing time: the first expresses the problem as an integer-programming problem that can be solved by a standard linear-programming package, and the second expresses the problem as a shortest-path problem in an acyclic directed graph, i.e. a dynamic-programming solution. The complexity of the integer-programming solution is difficult to predict; its main purpose is to act as an independent test of the correctness of the results returned by the second solution method. The dynamic-programming solution has best- and worst-case time complexity proportional to the square of the number of people. An empirical comparison of the efficiency of both methods is also presented. This manuscript has been accepted for publication in Science of Computer Programming. The manuscript has undergone copyediting, typesetting, and review of the resulting proof before being published in its final form. Please note that during the production process errors may have been discovered which could affect the content, and all disclaimers that apply to the journal apply to this manuscript

The Reorganization of the Traffic in the city of Opole during the Renovation of Niemodliński Bridge

In the near future the city of Opole, as well as the whole Opole Voivodship are going to suffer from a serious problem connected with the traffic system which provides for closing of the core bridge crossing from one part of the city to another one – the Ulga canal. The condition of the bridge crossing at Niemodlińska Street is constantly deteriorating. After the first expertise had been conducted by a construction supervision, the decision to close the bridge on 1st June 2015 was made. The decision is justified by the safety reasons and disastrous technical state of the bridge crossing. In order to delay the moment of the closing and lighten the bridge, the inside lanes were changed into bus lanes and thereby the centre of gravity has been moved closer to the bridge crossing axis. Cars are going to use outside lanes. In front of the bridge vehicles height limiters were set in order to eliminate trucks from the traffic. For this kind of vehicles a special detour was created (Wrocławska Street, Road No 45). After this procedure the next expertise of construction supervision was conducted whereby the exclusion of the bridge from the traffic was delayed for one year. For the time being, it is known that the third expertise is being prepared. During the bridge renovation the car drivers and public transport passengers who travel to work every day are going to come across the serious communication problem

Perencanaan Alternatif Desain Jembatan Jurang Gempal Kabupaten Wonogiri

Pokoh and Jurang Gempal bridge are the bridges that are located on Wonogiri – Ngadirojo roads crossing over Bengawan Solo river connecting Wonogiri Regency and Ponorogo Regency/Pacitan Regency. But in the past 10 years, only one bridge operates and that is Pokoh Bridge. This is caused by the condition of Jurang Gempal Bridge that is no longer adequate since it was built in the colonial era, some parts of the construction aren\u27t function properly. With only one bridge that is operating, it oftenly lead to a high traffic density on traffic hours. Thus, the re-operating of Jurang Gempal Bridge can be the solution of this traffic density problem that occurred. However, there is a need to do a total change on the bridge construction by seeing the existing condition and the age of the bridge that is already too old. Jurang Gempal Bridge was planned to be located in the existing location that is 2x60 meter in bridge length. The upper structure of this bridge is using steel frame that is 9.0 meter in width (2x3.5 meter vehicle floor and 2x1.0 meter sidewalk) and 6.0 meter in height. Meanwhile, the sub-structure of this bridge is using an abutment that the height is 7.0 meter and a pier that is 9.0 meter in height. The hard soil that is positioned in 10 meter depth is the kind of a sand soil so the Bored Pile is used as the foundation of this Jurang Gempal Bridge

Pelican Crossing System for Control a Green Man Light with Predicted Age

Traffic lights are generally used to regulate the control flow of traffic at an intersection from all directions, including a pelican crossing system with traffic signals for pedestrians. There are two facilities for walker crossing, namely using a pedestrian bridge and a zebra cross. In general, the traffic signals of the pelican crossing system are a fixed time, whereas other pedestrians need "green man" traffic lights with duration time arrangement. Our research proposes a prototype intelligent pelican crossing system for somebody who crosses the road at zebra crossings, but the risk of falling while crossing is not expected, especially in the elderly age group or pedestrians who are pregnant or carrying children. On the other hand, the problem is that the average step length or stride length (distance in centimeter), cadence or walking rate (in steps per minute), and the possibility of accidents are very high for pedestrians to make sure do crossing during the lights “green man”. The new idea of our research aims to set the adaptive time arrangement on the pelican crossing intelligent system of the traffic lights “green man” based on the age of the pedestrians with artificial intelligence using two combined methods of the FaceNet and AgeNet. The resulting measure can predict the age of pedestrians of the training dataset of 66.67% and testing prototype in real-time with participants on the pelican crossing system of 73% (single face) and 76% (multi faces)

Approximations for weighted Kolmogorov–Smirnov distributions via boundary crossing probabilities

© 2016, The Author(s). A statistical application to Gene Set Enrichment Analysis implies calculating the distribution of the maximum of a certain Gaussian process, which is a modification of the standard Brownian bridge. Using the transformation into a boundary crossing problem for the Brownian motion and a piecewise linear boundary, it is proved that the desired distribution can be approximated by an n-dimensional Gaussian integral. Fast approximations are defined and validated by Monte Carlo simulation. The performance of the method for the genomics application is discussed

Kinerja Persimpangan Jalan Emmy Saelan – Jalan Maluku, Jalan Wolter Monginsidi – Jalan Tj. Karang dan Jalan Emmy Saelan – Jalan Tj. Manimbaya

The purpose of this study is to determine the performance of intersections and provide solutions to problems that occur at the intersection of Emmy Saelan – Maluku street, and Wolter Monginsidi street – Tj. Karang street and Emmy Saelan street – Tj. Manimbaya street. The analysis included road performance, existing conditions and predictions over the next 5 years by calculating the average crossing delay based on the Indonesian Road Capacity Manual (MKJI)1997. From the results of research on the existing conditions DS = 1.24 crossing delay of Emmy Saelan street – Maluku street 55,89 det/smp that is in LOS E, intrection of Wolter Monginsidi – Tj. Karang street value of DS = 1.09 and corssing delay = 24.32 det/smp that is in LOS C and intersection of Emmy Saelan street – Tj. Manimbaya value of DS = 1.06 and crossing delay = 22.60 det/smp that is in LOS C. So it requires handling of the problem of intersections in the future, the first solution is to make the road median from intrection service levelof W. Monginsidi street – Tj. Karang street up to intrection of Emmy Saelan street – Anoa II street, with a median opening at the point before the bridge. Value of DS = 0.57 dan crossing delay of Emmy Saelan street – Maluku street = 10,16 det/smp that is in LOS B, intrection of Wolter Monginsidi street – Tj. Karang street value of DS = 0.76 dan crossing delay = 12.29 det/smp that is in LOS B and intrection of Emmy Saelan – Tj. Manimbaya street value of DS = 0.41 and crossing delay = 8.12 det/smp that is in LOS B

Identifying Traffic Problems in a Heavily Trafficked Urban Environment– Reference to Sowerby Bridge

1.1 BACKGROUND This study was commissioned by the Civic Trust to identify new approaches to traffic management solutions for Sowerby Bridge. The objective of the overall study was to identify low cost, innovative solutions to problems created by high volumes of traffic using the A58. This road is the main shopping street in Sowerby Bridge. In our brief it was stressed that any new road construction such as a by-pass was not a feasible or acceptable solution due to the severe vertical gradients surrounding Sowerby Bridge. Further, the town is on the brink of a major programme of regeneration. A nationally important canoe slalom has been created; the riverside mill area fronting onto the River Calder is being developed for commercial and leisure use and there is a proposal to reopen the Rochdale Canal. In view of this it is essential to ensure that traffic on the A58 is managed so as to minimise its effect on the environment and trade, without adversely affecting local access. In writing our report we have separated the problem and solution identification stages. The solution identification stage is reported in a companion report (Hopkinson et all 1988b). A further stage of our study which involves presenting our final solutions back to the users of Sowerby Bridge for comment is to be reported in a forthcoming report, WP 265 (Hopkinson et al, 1988c). 1.2 INTRODUCTION This Working Paper describes the methods used and findings from the first stage of our study carried out during October and November 1987 to identify the problems experienced by the users of Sowerby Bridge. Here it is intended to draw conclusions about the approach adopted to elicit people's impressions about problems, the way in which this information was interpreted and the applicability of the method to other situations

New results on stabbing segments with a polygon

We consider a natural variation of the concept of stabbing a set of segments with a simple polygon: a segment s is stabbed by a simple polygon P if at least one endpoint of s is contained in P, and a segment set S is stabbed by P if P stabs every element of S. Given a segment set S, we study the problem of finding a simple polygon P stabbing S in a way that some measure of P (such as area or perimeter) is optimized. We show that if the elements of S are pairwise disjoint, the problem can be solved in polynomial time. In particular, this solves an open problem posed by Loftier and van Kreveld [Algorithmica 56(2), 236-269 (2010)] [16] about finding a maximum perimeter convex hull for a set of imprecise points modeled as line segments. Our algorithm can also be extended to work for a more general problem, in which instead of segments, the set S consists of a collection of point sets with pairwise disjoint convex hulls. We also prove that for general segments our stabbing problem is NP-hard. (C) 2014 Elsevier B.V. All rights reserved.Peer ReviewedPostprint (author's final draft