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111.
License plate extraction method for identification of vehicle violations at a railway level crossing
B. K. Cho S. H. Ryu D. R. Shin J. I. Jung 《International Journal of Automotive Technology》2011,12(2):281-289
The primary cause of most railroad accidents is vehicle entry into railway level crossings despite warning messages. To identify
drivers who violate railway level crossing regulations, vehicle license plate recognition can be applied at railway level
crossings. The purpose of this paper is to present an effective method for extracting the license plate region from vehicle
images taken at railway level crossings. The method proposed in this paper uses the variation in the gray-level values across
the image of a license plate. For license plate region extraction, the character region is first recognized by identifying
the character width and the difference between the background region and the character region. The license plate region is
then extracted by finding the inter-character distance in the plate region. In addition, the license plate type is identified
by the difference in the gray-level value between the background region and the character region. The proposed method is effective
in solving the current challenges in extracting the license plate region from the damaged frames of license plates issued
for domestic use, including new types of license plates. According to the experimental results, the proposed method yields
a high extraction rate of 99.5% for vehicle license plates. 相似文献
112.
K. Jang I. Park J. Han K. Lee M. Sunwoo 《International Journal of Automotive Technology》2011,12(4):589-597
Because the FlexRay protocol has more than 70 configuration parameters and these parameters correlate with each other, designing
a FlexRay network is a complex and difficult task. In this study, we propose a design framework that optimizes the two main
FlexRay network parameters that are highly relevant to the application algorithm. The design process is composed of two steps
for optimizing parameters. In the first step, the static slot length is optimized using a frame-packing algorithm. This algorithm
binds network signals into static frames based on their periods and signal groups. In the second step, the communication cycle
length is optimally designed with frame-scheduling algorithm and worst-case reponse time analysis. Based on the frame-scheduling
algorithm, the response times are analyzed. The proposed design framework was applied to a unified chassis control system
as a case study, and the analytical results were verified. 相似文献
113.
114.
Identifying the components of a vehicle’s interior noise is important in many phases of the noise, vibration, and harshness
(NVH) development process. Many test methods that have been widely used in the automobile industry to separate noise sources
are based on system identification methods in the frequency domain. However, none of the frequency response function-based
methods can directly estimate the wind noise component. In this article, an analytical model for the interior noise level
based on a simple power law was developed. It was assumed that the mean squared acoustic pressure for the interior noise could
be obtained by summing up those of the wind noise, road noise, and background noise. The wind noise and road noise were further
assumed to depend only on wind speed and the vehicle’s driving speed, respectively, and to follow a simple power law. The
resulting analytical model includes five parameters that can be optimized for the vehicle and the road. The validity of the
model was verified by using data obtained from cruise tests performed on a proving ground for cruise speeds ranging from 40
km/h to 130 km/h. The model is applied to the overall and 1/3-octave bands of interior noise and is shown to describe the
data trends fairly well. For the test vehicle used in the present work, the overall mean squared pressures for the wind and
road noise components are shown to be proportional to the wind speed to the 5.8 power and to the driving speed to the 3.4
power, respectively. 相似文献
115.
H. H. Lee H. W. Bang S. K. Kauh S. I. Kim 《International Journal of Automotive Technology》2011,12(3):351-358
The development of an inner-piston-chamber temperature measurement system is a necessary step in engine development or when
solving other fundamental problems related to automotive engines. There are various pre-existing measurement methods available,
e.g., the linkage method, piston telemetry, templog, and the electromagnetic induction method. In this study, we first redesigned
the coil sensor used in the electromagnetic induction method using PEEK and then used Taguchi methods to reduce the number
of experiments in the development process and finally utilized piston telemetry via Bluetooth to verify the precision and
accuracy of the redesigned PEEK coil sensor and electromagnetic induction method. The results displayed a reproducibility
within 0.5 degrees and an accuracy within 2 degrees Celsius. 相似文献
116.
Seaport research: A structured literature review on methodological issues since the 1980s 总被引:1,自引:0,他引:1
Su-Han Woo Stephen J. PettitDong-Wook Kwak Anthony K.C. Beresford 《Transportation Research Part A: Policy and Practice》2011,45(7):667-685
This study aims to investigate how seaport research has been conducted from the methodological perspective. To this end, this study reviews published port literature for the last three decades (1980-2000s). The investigation primarily categorises the literature according to various methodological issues such as research paradigm, research strategy, base-disciplines, research methods and analysis techniques in order to provide meaningful implications on methodological evolution in seaport research for the period. This study suggests methodological bias in port research to a positivistic paradigm, following a quantitative trajectory moving from conceptual to empirical studies. In addition, the increased use of mathematical modelling and advanced statistical analysis methods is clearly observed. The introduction of advanced analytical tools used in other academic disciplines facilitates discussions in particular research area and amplifies the literature in those areas. This paper also suggests research gaps from the methodological perspective and implications for future port research. 相似文献
117.
John K. Stanley David A. Hensher 《Transportation Research Part A: Policy and Practice》2011,45(8):789-801
Building on a growing research foundation, transport policy makers have begun to associate the ability to be mobile with having a role in the facilitation of social inclusion. However, the further connection to well-being is not as well understood. This paper explores the association between a person’s travel patterns, their risk of social exclusion and self-assessed well-being. Key influences on social exclusion are discussed, with trip making emerging as a significant influence. Trip making is not a significant direct influence on well-being but does exercise an indirect influence through the impact on risk of social exclusion. The modelling process enables a value for additional trips to be estimated, the value being about four times the values derived from conventional generated traffic approaches. Similar high values are found in separate metropolitan and regional case studies, confirming the significance of the results. 相似文献
118.
119.
The public transport system of Karlsruhe, in particular its innovative services on jointly used heavy rail lines, has received substantial attention throughout the past 20 years. The discussion of the system and of its development has been rather limited in the past, mostly highlighting technical aspects. This paper provides an overview of the development, including the urban development, of the region and of the funding system. The ridership and financial development of the operator is documented in detail. Three case studies focus on the integration of the system development in the general political process of the region and demonstrate the limitations of the operator under its current ownership structures. 相似文献
120.
Environmental assessments are on the critical path for the development of land, infrastructure and transportation systems. These assessments are based on planning methods which, in turn, are subject to continuous enhancement. The substantial impacts of transportation on environment, society and economy strongly urge the incorporation of sustainability into transportation planning. Two major developments that enhance transportation sustainability are new fuels and vehicle power systems. Traditional planning ignores technology including the large differences among conventional, hybrid and alternative fuel vehicles and buses. The introduction of alternative fuel vehicles is likely to change the traditional transportation planning process because different characteristics need to be taken into account. In this study a sustainability framework is developed that enables assessment of transportation vehicle characteristics. Identified indicators are grouped in five sustainability dimensions (Environment, Technology, Energy, Economy and Users). Our methodology joins life cycle impacts and a set of quantified indicators to assess the sustainability performance of seven popular light-duty vehicles and two types of transit buses. Bus Rapid Transit receives the highest sustainability index and the pickup truck the lowest. Hybrid electric vehicles are found to have the highest sustainability index among all other passenger vehicles. A sensitivity analysis shows the proposed sustainability dimensions produce robust sustainability assessment for several weighting scenarios. The results are both technology and policy sensitive, thus useful for both short- and long-term planning. 相似文献