Spatio-Temporal Short-Term Urban Traffic Volume Forecasting Using Genetically Optimized Modular Networks

Abstract:   Current interest in short-term traffic volume forecasting focuses on incorporating temporal and spatial volume characteristics in the forecasting process. This article addresses the problem of integrating and optimizing predictive information from multiple locations of an urban signalized arterial and proposes a modular neural predictor consisting of temporal genetically optimized structures of multilayer perceptrons (MLP) that are fed with volume data from sequential locations to improve the accuracy of short-term forecasts. The results show that the proposed methodology provides more accurate forecasts compared to the conventional statistical methodologies applied, as well as to the static forms of neural networks.     

Immunotherapy as a Therapeutic Strategy for Gastrointestinal Cancer—Current Treatment Options and Future Perspectives

Gastrointestinal (GI) cancer constitutes a highly lethal entity among malignancies in the last decades and is still a major challenge for cancer therapeutic options. Despite the current combinational treatment strategies, including chemotherapy, surgery, radiotherapy, and targeted therapies, the survival rates remain notably low for patients with advanced disease. A better knowledge of the molecular mechanisms that influence tumor progression and the development of optimal therapeutic strategies for GI malignancies are urgently needed. Currently, the development and the assessment of the efficacy of immunotherapeutic agents in GI cancer are in the spotlight of several clinical trials. Thus, several new modalities and combinational treatments with other anti-neoplastic agents have been identified and evaluated for their efficiency in cancer management, including immune checkpoint inhibitors, adoptive cell transfer, chimeric antigen receptor (CAR)-T cell therapy, cancer vaccines, and/or combinations thereof. Understanding the interrelation among the tumor microenvironment, cancer progression, and immune resistance is pivotal for the optimal therapeutic management of all gastrointestinal solid tumors. This review will shed light on the recent advances and future directions of immunotherapy for malignant tumors of the GI system.     

Applying storm water management in Greek cities: learning from the European experience

This paper is based on the studies forming part of the European research project DayWater, which aims at the promotion of stormwater source control (participating countries: UK, France, Sweden, Denmark, Germany, The Netherlands and Greece). Source control techniques include all techniques (e.g. retention, infiltration, reuse) of stormwater treatment near its source, in contrast to end-of-pipe. In this paper we present: the different stormwater management issues across Europe; the specific stormwater management issues in Greece; source control techniques applied in European cities; Public policies for promoting source control techniques; Strategies of application of the aforementioned techniques and policies in Greek cities. In Greece, the question of stormwater treatment has not yet attracted a lot of attention. Wastewater management, flood prevention and fresh water scarcity issues are given priority instead. However source control stormwater management can contribute to the solution of all these problems. In many European cities source control techniques have been chosen for stormwater treatment because: a) they are less expensive than massive end-of-pipe treatment installations, b) they are more compatible with the natural water cycle, c) they reduce the overall stormwater flow and thus permit the expansion of cities without requesting reconstruction of the existing sewer networks. Different policy instruments (taxes, specific regulations and controls, information campaigns) have been applied in order to promote source control techniques. The main objective of this work is to discuss the possibility of applying similar techniques and policies in Greek cities.     

A New Methodology for Efficient Classification of Multispectral Satellite Images Using Neural Network Techniques

A methodology based on self-organizing feature maps and indexing techniques for time and memory efficient neural network training and classification of large volumes of remotely sensed data is presented. Results on land-cover classification of multispectral satellite images using two popular neural models show orders of magnitude of speedup with respect to both training and classification times. The generality of the proposed methodology is demonstrated with a dramatic improvement of the classification time of the k-nearest neighbors statistical classifier.     

Comparing hybrid learning with traditional approaches on learning the Microsoft Office Power Point 2003 program in tertiary education

The purpose of this study was to determine the effectiveness of a hybrid learning approach to deliver a computer science course concerning the Microsoft office PowerPoint 2003 program in comparison to delivering the same course content in the form of traditional lectures. A hundred and seventy-two first year university students were randomly assigned into two teaching method groups: traditional lecture instruction (TLI) and hybrid lecture instruction (HLI). Each group received six 95-min periods of instruction divided into 4 sections: a) 5-min brief outline of the key learning points, b) 40-min lecture on general knowledge c) 45-min constructivist-inspired learning activities and d) 5-min summary on key learning points. In the beginning and the end of this study students completed a 17-item multiple choice knowledge test. Two-way analysis of variances (ANOVA), with repeated measures on the last factor, were conducted to determine effect of method groups (TLI, HLI) and measures (pre-test, post-test) on knowledge test. The measures main effect was significant, as well as the groups x measures interaction effect. Two independent-samples t test were conducted to follow up the significant interaction. Differences in mean ratings of knowledge performance between the two teaching groups were not significantly different at first measure, while the TLI method group yielded a significantly lower mean rating at second measure. The findings indicated that HLI approach might be a superior option for undergraduate students on learning the Microsoft office PowerPoint 2003 program.     

Study of the thermal behaviour of alipharomatic polyesters around the glass–rubber transition region by thermomechanical analysis: the mobile and rigid amorphous fraction

The objective of this work was the study using thermomechanical analysis (TMA) of a peculiar behaviour, which was observed some years ago, around the glass–rubber transition region in some thermoplastic alipharomatic polyesters. For this purpose a series of nine alipharomatic polyesters was prepared by the two‐stage melt polycondensation method in a glass batch reactor and subjected to TMA in both penetration and expansion mode. Differential scanning calorimetry (DSC) was additionally used and the results are discussed focusing mainly on the first derivative curve of TMA thermograms in the penetration mode. From this curve, which shows two distinct peaks, the first peak could be attributed to the glass transition temperature (T_g) of the mobile amorphous fraction, since the value coincides with that obtained from DSC and is due to the abrupt shrinkage of the amorphous part of the sample. The second peak (up to 40 °C higher than T_g) is due most probably to the softening of the rigid amorphous fraction and the passage of the polymeric sample from the glass region to the cold crystallization region. When the sample is more crystalline than amorphous then the first peak is smaller or is completely absent. Copyright © 2006 Society of Chemical Industry     

Magnetic carbon nanotubes with particle-free surfaces and high drug loading capacity

Open-ended, multi-wall carbon nanotubes (CNTs) with magnetic nanoparticles encapsulated within their graphitic walls (magCNTs) were fabricated by a combined action of templated growth and a ferrofluid catalyst/carbon precursor, and tested as drug hosts. The hybrid nanotubes are stable under extreme pH conditions due to particle protection provided by the graphitic shell. The magCNTs are promising for high capacity drug loading given that the magnetic functionalization did not block any of the active sites available for drug attachment, either from the CNT internal void or on the internal and external surfaces. This is in contrast to typical approaches of loading CNTs with particles that proceed through surface attachment or capillary filling of the tube interior. Additionally, the CNTs exhibit enhanced hydrophilic character, as shown by water adsorption measurements, which make them suitable for biological applications. The morphological and structural characteristics of the hybrid CNTs are evaluated in conjunction to their magnetic properties and ability for drug loading (diaminophenothiazine). The fact that the magnetic functionality is provided from 'inside the walls' can allow for multimode functionalization of the graphitic surfaces and makes the magCNTs promising for targeted therapeutic applications.     

Modular construction of P3HT/PCBM planar-heterojunction solar cells by lamination allows elucidation of processing–structure–function relationships

Contrary to polymer solar cells with bulk-heterojunction active layers, devices with planar-heterojunction active layers allow the decoupling of active layer phase separation from constituent crystallization, and their relative influence on device performance. We fabricated planar-heterojunction devices by first processing the electron donor and electron acceptor in isolation; they were subsequently laminated across the donor–acceptor interface to establish electrical contact. Thermal annealing was intentionally avoided after lamination to maintain the pristine charge transfer interface. Lamination thus obviates the need for solvent orthogonality; more importantly, it provides independent process tuning of individual organic semiconductor layers, ultimately allowing control over constituent structural development. We found the short-circuit current density of planar-heterojunction solar cells comprising poly(3-hexyl thiophene), P3HT, and [6,6]-phenyl-C₆₁-butyric acid methyl ester, PCBM, as the electron donor and acceptor, respectively, to be generally independent of the annealing history of P3HT. On the contrary, thermal annealing PCBM prior to lamination mainly led to a reduction in short-circuit current density. This deterioration is correlated with the development of preferentially oriented PCBM crystals that hinders electron transport in the vertical direction.