Abstract

The lack of systematization in the collection of building defects leads to a wide range of data that is not used to its full potential. Unfortunately, this opportunity is missed since lessons could be drawn from analyzing this data by systematically mapping and investigating building defects. This paper presents the results of a statistical analysis on 27074 cases of building defects provided by a Belgian insurance company, ranging from 1991 up to 2019. This analysis focuses on the types of damage, the occurrence in relation to the construction time and the typology of the claims. Spearman correlation tests, X² tests, and Kruskal-Wallis tests are performed to assess the significance of correlations. Moisture problems constitute 49% of all technical defects, followed by structural issues (19%), and cracking (17%). Within the category of moisture problems, the roof is the dominant location for problems to occur, followed by basements, façades, windows, and rising damp. 50% of the judicial cases were closed after 3 years, whereas cases without lawsuit are typically settled after 1-2 years.

Abstract

Real time data collection in traffic engineering is crucial for better traffic corridor control and management. In the literature, many data collection methods have been used such as; magnetic loops, road tube counters, piezo sensors, radars, Bluetooth etc. to estimate the link occupancy, average speed or density of a corridor. More recently, Floating Car Data (FCD) has become another important traffic data source and has an increasing usage due to its lower cost and higher coverage despite its reliability problems. FCD obtained from GPS equipped vehicles moving in the traffic can provide speed or travel speed data for many segments for even 1-min intervals in real-time. Though not totally diverse providing more than one of the traffic flow parameters, measuring the effectiveness of this extensive data source in detecting some critical urban traffic states is the ultimate goal of this study. As a case study, 1-min interval FCD for an urban arterial in Ankara has been collected during the morning peak hour for 2 months. Average speed values were transformed into a qualitative 4-scale state parameter based on the Level of Service (LOS) definitions for urban roads. Pattern searches over consecutive segment states using different search length (i.e. 2 segments, 3 segments, etc.) showed that FCD is capable to detect recurrent congestion or bottleneck locations, and even have an idea about the length of queue formed before the bottlenecks. (C) 2016 The Authors. Published by Elsevier

Abstract

One of the key issues in mobile communication system is how to predict the number of calls per each cell. It is an important parameter and usually assumed as random Poisson value. For effective management of cellular network, the average number of calls should be traced and the changes in the numbers need to be promptly detected. In this paper we propose an algorithm detecting the changes in the behavior of the users using the technique proposed for point-of-change problem based only on the number of call arrivals. Computer simulation reveals that the proposed method can effectively detect the discord, and the developed model is very accurate as showing mostly less than 1% differences. Document type: Part of book or chapter of book

Abstract

International audience; Based on a clustering indicator, an alteration of the classical road traffic indicators is proposed for incident detection. The resulting filter method reduces the inaccuracies of comparable detection method and enables to better separate usual traffic patterns from non-recurrent situations. Three alternative detection approaches are considered as baseline comparison for performance estimation.

Abstract

Many agencies nationwide have adopted video vehicle detection technology as an alternative to inductive loops. While many product evaluations have been performed, the majority of these evaluations have concentrated on freeway applications where speed and volume were the primary evaluation criteria. At an actuated intersection, the metrics of speed and volume do not necessarily represent how well a device will operate as a presence detector. Video detection was evaluated at two signalized intersections in West Lafayette, Indiana and Noblesville, Indiana. A camera on each approach was located at the vendor recommended position, at a height of 40 feet and offset so that the camera was approximately inline with the lane line dividing the left-turn lane and through lane. Two additional cameras were located on each approach at less optimal horizontal and vertical locations. Additionally at the West Lafayette site, a fourth camera was located directly above the stop bar so that it looked down onto the detection zone. Inductive loops were used as baseline data to screen for discrepancies. Each time the loop detectors were not in agreement with a specific video detector, a discrepancy was noted. A digital video recording was later observed to determine whether the video detector or the loop detector was in error. An analysis of the data showed video detection was found to produce statistically significantly more false detections and missed detections than the loop detectors on most phases. Generally, only very small variations in video detector performance were observed at the different camera locations. The video detection was also evaluated in terms of its’ consistency of detector turn-on and turn-off times. The video detection displays an undesirable inconsistency between night periods and day periods where it tends to activate 1 to 3 seconds earlier during the night period due to headlight reflections on the pavement. However, the camera at West Lafayette located directly above the stop bar displayed very consistent behavior between the night and day periods.

Abstract

On well-illuminated approaches, vehicle headlight reflections on the pavement were observed to cause video detection units to activate early. This early activation results in a dramatic increase in the length of the effective vehicle detection zone. This observed variation in the effective length of the vehicle detection zone that varies by ambient lighting condition and camera placement presents a very serious impediment for traffic engineers to design vehicle extension intervals that operate correctly during day, night and transition periods. Furthermore, the stochastic variation in the length of the vehicle detection zone length has the potential to create driver expectancy issues. Tables are included that reports the observed average and range of detection zone length variations for 16 observed video cameras that were extensively calibrated by the manufacturer at the test site. The paper concludes by recommending near-side placement of video detection devices to reduce the stochastic variation in detection zone length.

Abstract

International audience; This paper describes the analysis of recorded data parameters from electrical battery ageing during electric vehicle use. These data allow traditional battery ageing investigation based on resulting capacity fade and resistance raise. The measured variables are examined in order to explain the battery ageing obtained during the experiment. Such study enables us to identify the main ageing factors. Then, detailed statistical dependency explorations present results on battery ageing phenomena. All studies are done on real data collected from Lithium-ion battery; thereby results demonstrate and quantify a relationship between variables and battery ageing mechanisms.

Abstract

International audience; Conflict probes will be important components of air traffic control tools in the next years. They appear in almost every project (CINCAT, ERATO, HIPS, PHARE, and so on). To be useful, they have to fulfill two goals : reliability (they have to detect all conflicts) and efficiency (they must minimize the number of false alarms). Conflict probes rely on trajectory prediction, and their reliability and efficiency highly depend on the accuracy of trajectory prediction. In this paper, we present a quick mathematical insight of the influence of ground speed errors on trajectory prediction, results of arithmetic simulations on real traffic both on ground and vertical speed errors, and a statistical analysis of these results to model the influence of vertical and ground speed errors on conflict probe.