Enabling the freight traffic controller for collaborative multi-drop urban logistics: practical and theoretical challenges

There is increasing interest in how horizontal collaboration between parcel carriers might help alleviate problems associated with last-mile logistics in congested urban centers. Through a detailed review of the literature on parcel logistics pertaining to collaboration, along with practical insights from carriers operating in the United Kingdom, this paper examines the challenges that will be faced in optimizing multicarrier, multidrop collection, and delivery schedules. A “freight traffic controller” (FTC) concept is proposed. The FTC would be a trusted third party, assigned to equitably manage the work allocation between collaborating carriers and the passage of vehicles over the last mile when joint benefits to the parties could be achieved. Creating this FTC concept required a combinatorial optimization approach for evaluation of the many combinations of hub locations, network configuration, and routing options for vehicle or walking to find the true value of each potential collaboration. At the same time, the traffic, social, and environmental impacts of these activities had to be considered. Cooperative game theory is a way to investigate the formation of collaborations (or coalitions), and the analysis used in this study identified a significant shortfall in current applications of this theory to last-mile parcel logistics. Application of theory to urban freight logistics has, thus far, failed to account for critical concerns including (a) the mismatch of vehicle parking locations relative to actual delivery addresses; (b) the combination of deliveries with collections, requests for the latter often being received in real time during the round; and (c) the variability in travel times and route options attributable to traffic and road network conditions

PPAR-alpha L162V polymorphism in human hepatocellular carcinoma

Background/aims: Several lines of evidence suggest that peroxisome proliferator-activated receptor alpha may be involved in hepatocarcinogenesis. L162V polymorphism of the peroxisome proliferator-activated receptor alpha gene enhances the transactivation activity of this transcription factor. The aim of this study was to determine the frequency and clinical correlates of peroxisome proliferator-activated receptor alpha L162V polymorphism in hepatitis virus-induced hepatocellular carcinoma. Methods: 90 hepatocellular carcinoma patients diagnosed at Ankara University Gastroenterology Clinic between January 2002 and July 2003 and 80 healthy controls with normal body mass index, blood chemistry and with negative viral serology were included. peroxisome proliferator-activated receptor alpha L162V polymorphism was determined by PCR-RFLP. Results: hepatocellular carcinoma etiologies were as follows: 56 HBV, 12 HBV+HDV, 22 HCV. Eighty-seven patients (97%) were cirrhotic, and 60 patients (67.5%) had advanced tumors. In 83 (92%) of 90 hepatocellular carcinoma patients, gene segment including polymorphic region could be amplified by PCR (50 HBV, 12 HBV+HDV, 21 HCV) and 6 of them (7.2%, all infected with HBV) had L162V polymorphism, while 2 (2.5%) of 80 controls had this polymorphism (p=0.162). This trend became more remarkable when only HBV (HBV+HDV)-infected patients were compared with controls (6/62, 9.7% vs. 2/80, 2.5%, respectively, p=0.071). Five of 6 patients with L162V had advanced disease. Conclusions: Peroxisome proliferator-activated receptor alpha L162V polymorphism tends to occur in HBV-induced epatocellular carcinoma and is absent in HCV-related epatocellular carcinoma. These findings may show clues for the existence of different carcinogenesis mechanisms in these two common etiologies. Frequent occurrence of advanced disease in patients with L162V polymorphism suggests a role for this polymorphism in tumor progression

GeoGCD: improved visual search via gaze-contingent display

Gaze-Contingent Displays (GCDs) can improve visual search performance on large displays. GCDs, a Level Of Detail (LOD) management technique, discards redundant peripheral detail using various human visual perception models. Models of depth and contrast perception (e.g., depth-of-field and foveation) have often been studied to address the trade-off between the computational and perceptual benefits of GCDs. However, color perception models and combinations of multiple models have not received as much attention. In this paper, we present GeoGCD which uses individual contrast, color, and depth-perception models, and their combination to render scenes without perceptible latency. As proof-of-concept, we present a three-stage user evaluation built upon geographic image interpretation tasks. GeoGCD does not impair users’ visual search performance or affect their display preferences. On the contrary, in some cases, it can significantly improve users’ performance

Knowledge sharing in megaprojects: A case study of a co-location approach

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