Marinos Stylianou

Preliminary study for the management of construction and demolition waste

This paper refers to the management of the construction and demolition (C&D) waste since, according to the EU Waste Strategy, C&D waste is considered to be one of the priority waste streams and appropriate actions need to be taken with respect to its effective management. Initially, the paper presents the state-of-the-art of the problem of C&D waste, including the amount and composition of C&D waste in EU countries, differences in the characteristics of this waste stream depending on its origin, as well as collection and management practices that are applied. A methodology is described for the estimation of the quantities of the waste stream under examination, since in most cases quantitative primary data is not available. Next, the fundamentals for the development of an integrated scheme for the management of C&D waste are presented and discussed, such as appropriate demolition procedures and location of waste management (off-site waste management, on-site waste management, direct on-site recovery, centralized on-site recovery). Finally, taking into consideration all relevant parameters, alternative systems that could be applied for the management of the C&D waste are suggested.

A roadmap for research in mobile business

Mobile business research has arguably grown to become one of the most topical and complex eBusiness research areas in recent years. As a result, researchers face a plethora of interdisciplinary research challenges. Understanding the range of these challenges and confronting them requires coordinated research efforts, backed up by a holistic guiding approach. This paper aims at contributing to the future of mobile business research by proposing a roadmap to systematise and guide future research efforts, providing a methodical outlook to open research issues across all dimensions defining mobile business and prioritises future research in each dimension in the form of short-, medium-, and long-term research challenges.

An integrated approach for the management of demolition waste in Cyprus

This study investigated the generation and management of demolition waste (DW) in Cyprus. A methodology has been developed and applied for the estimation of the quantities of the waste stream under examination, since quantitative primary data were not available. The existing situation relating to the practices applied for the management of DW was investigated and assessed. Furthermore, a multi-criteria analysis method (PROMETHEE II) was developed and applied in order to examine alternative systems that could be implemented for the management of the DW in the country. In particular, nine management systems (scenarios) were examined, evaluated and ranked according to their efficiency using seventeen individual criteria, divided into four groups (social—legislative, environmental, economic and technical). The ranking of the alternative waste management scenarios indicated that the optimum management system for possible implementation in the island included complete selective demolition procedures and transfer of mixed recyclable materials to the recycling centre and non-recyclable material to landfill.

Comparison of Mn, Zn, and Cr removal in fluidized- and fixed-bed reactors by using clinoptilolite

AbstractNatural minerals are used as sorbents in ion-exchange processes due to their high exchange capacity and their relatively low cost. In the present study the use of natural zeolite as filling medium in fixed- and fluidized-bed reactors for the removal of heavy metals from aqueous solutions is investigated. The major objective is to compare the removal efficiency of heavy metals by the two processes—fluidized and fixed bed. Fixed and fluidized bed experiments were conducted in order to examine the Mn2+, Zn2+, and Cr3+ uptake by natural clinoptilolite, using the same critical experimental conditions: particle size (90–180 μm), volumetric flow rate of 12.48 BV/h, total normality of 0.01 N, initial pH value equal to 4, and ambient temperature (25°C). The fluidized bed process was conducted in an experimental 50 cm long plexiglass column of 4.4 cm internal diameter and fixed bed experiments in 70 cm long plexiglass columns of 2 cm internal diameter. The fluidized bed breakthrough curves for Mn2+ and Zn2+...

Ran Selection for Converged Networks Supporting IMS Signalling and MBMS Service

Future communication networks are envisioned to be based upon a common, flexible and scalable convergence platform, where different access networks, different terminals and different services can coexist. The new user capabilities spawn a demand for Always Best Connectivity (ABC), i.e. that a user can always have the best possible connection regardless of place and time. This brings forth a new communication paradigm, which is user-centric, i.e. the user is no longer bound to only one access network but can choose the best available access network to satisfy a specific service request. The IP multimedia subsystem (IMS) is the technology promoted to enable this ubiquitous converged network. This paper considers the selection of access network, specifically for multicast/broadcast users and proposes a novel RAN selection scheme implemented using IMS signalling.

Sustainable Treatment Method of a High Concentrated NH3 Wastewater by Using Natural Zeolite in Closed-Loop Fixed Bed Systems

The aim of this study is to investigate ammonium removal from a wastewater resulted after homogenization and anaerobic digestion of a mixture of wastes and wastewater from animal processing units and sewage sludge, by using natural zeolite clinoptilolite. Batches as well as closed loop fixed bed system (CLFB) are studied, offering an alternative to conventional fixed bed systems. The experimental results showed that the optimum pH is in the vicinity of 6.48, where the achieved removal in the batch system reached 46%. The CLFB system, under the same experimental conditions and relative flow rate of 2.56 BV h -1 , reached a removal of 55%, which is almost 22% higher. In the CLFB the removal of ammonia could be further increased by diluting the initial solution by 1/8, reaching the level of 96%. The achieved zeolite loading, for all studied systems, is between 2.62 and 13 mg g -1 . This kind of operation is very useful for relatively high concentration and small volumes of wastewater and in systems that there is no need for continuous flow operation.

Enhanced UMTS Cellular Planning for Multiple Traffic Classes in Offices Scenarios

It is shown that enhanced UMTS is an affordable solution for providing the required network quality and to reduce infrastructure investments in offices scenarios. System capacity results are obtained by using a system level simulator which considers traffic characterisation parameters and services usage in detail, among other. Results for the most profitable cell radius are obtained via an optimisation procedure based in economic aspects. A higher number of pico cells (with a smaller radius, around 30-32 m) can be installed in the future, when costs of deploying and maintaining the network decreases, allowing for supporting higher system capacity, and reducing prices. Our approach is based in a detailed services analysis, which represents a worst case situation relatively to the total services approach, because the later does not discriminate results for the different traffic classes. The impact of call blocking, handover failure, end-to-end delay, and delay variation are taken into account