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When designing biomass-to-biofuel supply chains, the biomass uncertainty, seasonality and geographical dispersion that affect economic viability need to be considered. This work presents a novel methodology that can optimize the design of biofuel supply chains by adopting a decentralized network structure consisting of a mix of fixed and mobile processing facilities. The model considers a variable biomass yield profile and the mobile fast pyrolysis technology. The mixed-integer linear programming model developed identifies the optimal biofuel production and biomass harvesting schedule schemes under the objective of profit maximization. It was applied in the case study of marginal lands in Scotland, which are assumed to be planted with Miscanthus. The trade-offs observed between economies of scale against the transportation costs, the effect of the relocation costs and the contribution of storage capacity were investigated. The results showed that, in most cases, harvesting is most concentrated during the month of the highest biomass yield, provided that storage facilities are available. Storage capacity plays an important role to widen the operational time window of processing facilities since scenarios with restricted or costly storage resulted in facilities of higher capacity operating within a narrower time window, leading to higher investment costs. Relocation costs proved to have a minor share in the total transportation costs.

Public Transit (PT) systems aim to provide social, economic, and environmental benefits to modern cities offering reliable transportation service to users and ultimately reducing the problems related to traffic externalities due to car dependency. With the growing trend of urbanization and the associated phenomenon of cities’ sprawl being increasingly evident, significant attention should be given to understanding PT systems’ performance and then improving their efficiency. Considering the spatial characteristics of the PT system's performance promotes the environmentally friendly transport “character” that every city endeavors. This paper aims to incorporate the spatial spillover effects of a realistic PT system by augmenting information about the service network along with socio-economic variables, in a spatial demand-supply econometric framework. In detail, geographically separated demand and supply information on bus stops and lines was analyzed by a spatial econometric model, namely, the Spatial Lagged X (SLX) model which may be formatted so that can soundly handle, spatial and –in particular- network data like those coming from the General Transit Feed Specification (GTFS) protocol widely used in PT systems. The novelty and the importance of the proposed model rely on the ability to introduce transit network structure within the framework of spatial econometric regression, fostering the explanatory statistical analysis over networked information. The developed modeling approach was applied to the urban and rural PT system of Nicosia (Cyprus), incorporating the spatial spillover effects of the system over more than 1,500 bus stops, 40 lines, and 252 different but spatially connected postcode areas. The results of the SLX model were compared with other demand models of this form typically used, namely the Ordinary Least Square model and standard Spatial Autoregressive models, providing solid evidence of the benefits of incorporating the network structure in spatial demand modeling, giving valuable input for further planning purposes.

Byline: Fotis N. Koumboulis, George E. Panagiotakis, Paraskevas N. Paraskevopoulos The problem of Exact Model Matching (EMM) for general left invertible neutral multidelay systems, via proportional realisable state and output feedback, is extensively solved. The necessary and sufficient conditions for the problem to have a realisable solution are established. The general analytical expression of the controllers, solving the problem, is derived. The present results are rather useful to adaptive control of distributed industrial processes described by neutral time delay models.

Urbanization is one of the most dominant economic and social changes of the 20th century. This phenomenon brings about rapid urban development, which is inextricably linked to transport development. In order to understand this relationship, it is important to analyze the spatial spillover effects of the phenomenon in the urban environment. This study analyzes the spatial performance, in terms of urban development, of 12 European Union regions from five European countries with coastal areas by incorporating spatial data such as length of road network, population distribution, land uses, and other factors. Key performance indicators have been developed for evaluating the structural development model of the regions (e.g., dense or sprawl development). In addition, the incorporation of spatial spillover effects in the evaluation of the regions was conducted by the extended spatial data envelopment analysis (SDEA) method. The results of SDEA identified the best and worst-performing regions in terms of urban growth. Finally, this study implements a target-setting approach where under-performing regions can best perform. Based on the target-setting approach, local authorities can set realistic targets for improving the structural model that the regions are following.

Objective: The clinical profile, management and outcome of infective endocarditis (IE) may be influenced by socioeconomic issues. Methods: A nationwide prospective study evaluated IE during the era of deep economic crisis in Greece. Epidemiological data and factors associated with 60-day mortality were analyzed through descriptive statistics, logistic and Cox-regression models. Results: Among 224 patients (male 72.3%, mean age 62.4 years), Staphylococcus aureus (n = 62; methicillin-resistant S. aureus (MRSA) 33.8%) predominated in the young without impact on mortality (p = 0.593), whilst Enterococci (n = 36) predominated in the elderly. Complications of IE were associated with mortality: heart failure [OR 2.415 (95% CI: 1.159–5.029), p = 0.019], stroke [OR 3.206 (95% CI: 1.190–8.632), p = 0.018] and acute kidney injury [OR 2.283 (95% CI: 1.085–4.805), p = 0.029]. A 60-day survival benefit was solely related to cardiac surgery for IE during hospitalization [HR 0.386 (95% CI: 0.165–0.903), p = 0.028] and compliance with antimicrobial treatment guidelines [HR 0.487 (95% CI: 0.259–0.916), p = 0.026]. Compared with a previous country cohort study, history of rheumatic fever and native valve predisposition had declined, whilst underlying renal disease and right-sided IE had increased (p < 0.0001); HIV infection had emerged (p = 0.002). No difference in rates of surgery and outcome was assessed. Conclusions: A country-wide survey of IE highlighted emergence of HIV, right-sided IE and predominance of MRSA in the youth during a severe socioeconomic crisis. Compliance with treatment guidelines promoted survival.

Greek cities hold important urban issues related to social injustice; lack of open spaces, pedestrian facilities, parks and greenery, access to public amenities, etc. In view of these, we investigated residents’ preferences and choices regarding their walking activities in the urban environment of Thessaloniki, Greece. In specific, we applied research with questionnaires to the residents of the municipality of Ampelokipoi-Menemeni. The research applied the Contingent Valuation Method to investigate residents’ willingness to pay (WTP) for the improvement of the existing infrastructure of public space in view of making walking and the use of local metro stations more attractive. A methodological framework was developed, including Explanatory Factor Analysis and Structural Equation Modelling, along with statistical analysis of the results. The lack of pedestrian facilities and the long walking distances are two main reasons discouraging the use of the metro. CVM application showed that almost half of the residents would be willing to contribute an amount of money for the improvement of pedestrian infrastructure. The main reasons for this were to make the use of the metro more attractive, which would also improve their living conditions and would contribute to a better quality of life. Income restrictions proved highly important to a negative WTP.

The growing competition among container port terminals enhances the pressure for optimizing their efficiency level in the performance of containers’ service. Comparing container terminals based on their performance is a complicated task due to the variety of ports’ type, scale, and service configuration. This however is an important task in the efforts of improving not only national trade transportation but also the global trade system, since valuable best practices can be identified and adopted among container terminals. Notwithstanding, available information about container port terminals’ efficiency level, based on their performance measured by the service of Twenty-foot Equivalent Units (TEUs), is yet incomplete due to the lack of information about which factors influence their efficiency the most. This additional information will support the decision-making processes of container terminals’ authorities to direct their focus on specific factors that will improve their efficiency. This paper investigates the efficiency of the top-50 global container port terminals that service the global freight supply chain in a period of 5 years (2013-2017) through a two-step procedure. First, a benchmarking analysis, namely, Data Envelopment Analysis, is implemented to estimate the efficiency level of the container port terminals. The second step involves the methodology followed in this paper which is further expanded to quantify the effects that different factors have on container terminals efficiency through the implementation of suitable Tobit regression models. The findings of this paper identify the benchmark container terminals that should be taken as examples for under-performing container port terminals and also points out the factors that must be enhanced for improving global trade system, like, number of cranes, terminal space and quay lenght.

Purpose: To report endovascular treatment of 2 patients with aneurysmal deterioration of peripheral arterial allografts. Case Report: Two men (65 and 64 years old) who had undergone an arterial allograft reconstruction for infection of prosthetic infrapopliteal bypass grafts 5 and 7 years ago, respectively, were diagnosed with asymptomatic aneurysmal deterioration of the allografts. Stent-graft repair was successful in both cases, completely excluding the aneurysms. At >or=1 year, continued aneurysm exclusion was confirmed by duplex scan, with no evidence of endoleak, migration, or stenosis. Conclusion: Endovascular treatment may be a useful therapeutic option when treating patients with late peripheral allograft deterioration. [ABSTRACT FROM AUTHOR]

The control of unstable first-order plus dead-time (UFOPDT) processes using proportional-integral (PI) and proportional-integral-differential (PID) type controllers is investigated in this brief. New tuning rules based on the exact satisfaction of gain and phase margin specifications are proposed. The tuning rules are given in the form of iterative algorithms, as well as in the form of accurate, analytical approximations. Moreover, several specific functions, related to the crossover frequencies of the Nyquist plot and to the feasible design specifications for a given process, are derived. These functions, which are particularly useful for the general design of PI- and PID-type controllers for UFOPDT processes are accurately approximated, in order to simplify the tuning procedure. With the proposed approximations, the tuning rules reported in this brief require relatively small computational effort and are particularly useful for online applications. [ABSTRACT FROM AUTHOR]