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In transportation, LiDAR sensors have been primarily used in surveying and autonomous driving as a major onboard sensing device to detect field objects. Recently, with reduced price and increased d...

The paper proposed a Personalize Parking Guidance Service(PPGS), in which a bi-level programming model was built to describe the relationship between the Personalized Parking Guidance Information S...

The Menzerath-Altmann law (henceforth the MA law), discovered by Menzerath and formulated by Altmann, describes the correlation between the language structure and its immediate components at all li...

Probabilistic yielding behavior is often observed at unsignalized crosswalks, but its impacts on the traffic flow in terms of traffic capacity and associated vehicular delay have not been examined before. The uniqueness of this problem is that neither traffic nor pedestrian flow holds the absolute priority as normally assumed in existing literature. Based on queuing theory, this paper developed traffic capacity and delay formulas considering the probabilistic priority. The proposed capacity equation reduces to the classic formula when the yielding rate equals one. The service time distributions for both queuers and non-queuers were derived, and M/G2/1 queuing model was applied to determine queue length and vehicular delay. Stochastic simulations showed that the proposed capacity and delay formulas precisely match the simulation results. For ease of practical applications, simpler queuing formulas including M/G/1, M/M/1 and M/D/1 were also examined. Noting that the differences between M/G2/1 and M/G/1 mode...

Vaccinium corymbosum (blueberry) is touted as a superfood with numerous health benefits due to its high levels of flavonoids. Flavanone 3-hydroxylase (F3H) is a key regulatory enzyme of the flavonoid pathway. In this study, we cloned the full-length cDNA of F3H (designated VcF3H) from young blueberry leaves using rapid amplification of cDNA ends (RACE). The cDNA contained a 1080-bp open reading frame that encoded a 359-amino acid protein. The deduced VcF3H protein showed high similarities to other plant F3Hs. Conserved amino acid motifs required for ferrous iron binding (HXD) and 2-oxoglutarate binding (RXS) were identified in VcF3H, VcFLS (flavonol synthase), and VcANS (anthocyanidin synthase). Quantitative RT-PCR analysis demonstrated that VcF3H was expressed in all tissues tested, with particularly high expression in young leaves, fruits (pink and blue), and stems. Anthocyanins accumulated mainly in fruits, whereas flavonols were found mainly in leaves and stems. Furthermore, the expression pat...

Compared to major structural repair or even replacement, preventative preservation of in-service pavements has been more popular in engineering practices, but recently, pavement preventative maintenance (PPM) has become more complex in China as the competition for pavement preservation funds has grown and the need to justify decisions has increased. Therefore, the life cycle cost analysis (LCCA) has increasingly attracted attention from transportation agencies. However, most of previous studies were conducted deterministically or only focused on a single factor, while PPM is apparently affected by many potential sources of uncertainty. The risk-based analysis to investigate potential risks and combined effects of multiple factors is a necessary component of PPM. This paper aims at presenting a risk-based PPM with the probabilistic LCCA for a Chinese highway case. Major analysis variables of different range are examined to probe risks of different scenarios, investigate combined effects of multiple variabl...

Unsignalised pedestrian crosswalks are commonly adopted in school and residential areas. To enhance pedestrian safety, various types of signs and crosswalk markings have been implemented, which results in motorists’ probabilistic yielding behaviour and interrupted traffic flow patterns. Predicting the vehicular delay is of central importance to evaluate the level of service. However, as the interaction involves two random streams and is governed by the uncertain yielding behaviour, the analysis could be fairly challenging. In this paper, a novel method is proposed to estimate vehicular delay, which decomposes the vehicular stream into free-flow and queuing traffic. By explicitly considering the relation between the vehicular headway and the critical gap, the probability of a yielding event is derived to the expected proportion of queue formation, queue dispersion and free-flow periods. Equations of the average vehicular delay are given as a function of the vehicle volume, pedestrian volume and the yieldin...

The day-to-day volatility of traffic series provides valuable information for accurately tracking the complex characteristics of short-term traffic such as stochastic noise and nonlinearity. Recently, support vector regression (SVR) has been applied for short-term traffic forecasting. However, standard SVR adopts a global and fixed ϵ-margin, which not only fails to tolerate the day-to-day traffic variation, but also requires a blind and time-consuming searching procedure to obtain a suitable value for ϵ. In this work, on the ground of stochastic modeling of day-to-day traffic variation, we propose an adaptive SVR short-term traffic forecasting model. The time-varying deviation of the day-to-day traffic variation, described in a bilevel formula, is integrated into SVR as heuristic information to construct an adaptive ϵ-margin, in which both local and normalized factors are considered. Comparative experiments using field traffic data indicate that the proposed model consistently outperforms the standard SVR...

An intermodal transportation terminal is a facility that provides commuters with easy transfer between transit modes and providers such as buses, light rail, subway, taxis, airport shuttles, and commuter rail. The probability of a passenger transferring from one mode to another and the estimation of total transfer demand are of great importance to both practitioners and researchers when determining optimal design alternatives as well as the best control and management policies for daily operation of the terminal. This article presents a study that uses an entropy-based optimization approach to estimate the transfer demands between the available transportation modes in an intermodal transportation terminal. The development and calibration of the entropy model is presented in the first part of the article, which is followed by a case study of the SiHui Intermodal Terminal in Beijing, China.

Map-matching, which reconciles a vehicle's location with the underlying road map, is a fundamental function of a land vehicle navigation system. This article presents an improved Kalman filter approach whose state-space model is different from the conventional ones. The main objective of the research is to develop and apply a proper Kalman filter–based model for effectively correcting Global Positioning System (GPS) errors in map-matching. Based on the in-depth investigation of the characteristics of GPS errors, the authors presents a novel approach to update the state vector and other related parameters of the Kalman filter using both the historical tracks and road map information. The performance of the proposed approach is thoroughly examined by sample applications with real field data. The result shows that it handles the biased error and the random error of the GPS signals reasonably well in both the along-road and cross-road directions.

Limin Ma,1 Linhai Ruan,1 Hongchao Liu,2 Haiping Yang,1 Yanming Feng2 1Department of Hematology, The First Affiliated Hospital, 2Medical College, Henan University of Science and Technology, Luoyang, People’s Republic of China Introduction and objective: Many studies have been conducted on the association between the adenosine triphosphate-binding cassette, subfamily B, member 1 (ABCB1) gene C3435T polymorphism and leukemia risk, however, the previously published findings remain controversial. Thus, a meta-analysis was carried out to accurately evaluate the effect of this polymorphism on leukemia susceptibility. Methods: A computerized literature search was conducted of PubMed, Elsevier database, the China National Knowledge Infrastructure database, and Wanfang Database, to find published case–control studies exploring the relationship between ABCB1 C3435T polymorphism and leukemia risk. Odds ratios (ORs) with 95% confidence intervals (CIs) were applied to assess the strength of association. Results: A total of 17 studies of 2,431 cases and 3,028 controls were included in this meta-analysis. The results of overall comparisons suggest that there is a significant association between ABCB1 C3435T polymorphism and leukemia risk under two genetic models (TT vs CC: OR=1.39, 95% CI=1.04–1.84, P=0.02; CT+TT vs CC: OR=1.20, 95% CI=1.06–1.36, P=0.004). In the subgroup analyses by ethnicity, age, and leukemia subtype, a significant association was found in Caucasian (CT vs CC: OR=1.22, 95% CI=1.03–1.45, P=0.02; TT vs CC: OR=1.34, 95% CI=1.10–1.64, P=0.004; CT+TT vs CC: OR=1.27, 95% CI=1.08–1.49, P=0.004), adult leukemia (CT vs CC: OR=1.46, 95% CI=1.17–1.83, P=0.001; CT+TT vs CC: OR=1.43, 95% CI=1.01–2.03, P=0.04), and lymphocytic leukemia (TT vs CC: OR=1.73, 95% CI=1.19–2.51, P=0.004; TT vs CC+CT: OR=1.62, 95% CI=1.10–2.38, P=0.01; CT+TT vs CC: OR=1.28, 95% CI=1.10–1.48, P=0.001). Conclusion: The meta-analysis suggests that ABCB1 C3435T polymorphism is associated with increased risk of leukemia. Keywords: adenosine triphosphate-binding cassette, subfamily B, member 1 gene, multidrug-resistance gene, meta-analysis

This is the first of two parts of the Special Issue on Intelligent Vehicle Navigation (iVN). iVN, as a core element of Intelligent Transport Systems (ITS), has the potential to make a significant c...