Creation of Zero CO₂Emissions Residential Buildings due to Operating and Embodied Energy Use on the Island of Crete, Greece

The possibility of creating zero CO2 emissions residential buildings due to life cycle energy use in the island of Crete, Greece has been examined. In a typical residential building located in Crete, Greece, its annual operating energy has been appraised at 170 KWh/m2 and its embodied energy at 30 KWh/m2. Various locally available renewable energies including solar energy, solid biomass and low enthalpy geothermal energy with heat pumps have been considered for generating the required heat and offsetting the grid electricity used. Their technologies are mature, reliable and cost-effective. Offset of the annual grid electricity use in the building with solar-PV electricity is allowed according to the net metering regulation. For zero carbon emissions due to embodied energy of the building, generation of additional solar electricity injected into the grid is required. A mathematical model has been developed for sizing the required solar-PV system installed in the building in order to offset the grid electricity use. For a residential building in Crete, Greece with a covered area of 100 m2, the power of the additional solar-PV system has been estimated at 1.6 KWp and its cost at 2400 €. In the current work, it is indicated that the creation of a zero CO2 emissions residential building due to life cycle energy use in Crete, Greece does not have major difficulties and it could be achieved relatively easily.

Description and Assessment of a Small Renewable Energy Community in the Island of Crete, Greece

A description and assessment of a small renewable energy community located in Crete, Greece is presented. The community included private residential and agricultural activities without any involvement of the public sector. Small-scale decentralized energy systems were used. Solar energy and solid biomass which are locally available covered most of the heat and electricity requirements in the community. Renewable energy technologies used include solar thermal energy, solar-PV and solid biomass burning utilizing olive tree wood and olive kernel wood. These technologies are mature, reliable, well proven in Crete and cost-effective. Existing energy systems were generating 857,877 kWh per year covering 94.46% of the current energy requirements in the community, significantly reducing its emissions at 278,494 kg CO2 per year. The addition of a new solar-PV system with nominal power of 33.6 kWp could cover all the remaining electricity needs in the community, transforming it to a zero-CO2 emission community due to energy use. The total installation cost of the existing renewable energy systems in the community was estimated at 0.16€ per total kWh of thermal and electric energy generated annually and at 0.50€ per ton of CO2 emissions saved annually. Results indicated that the creation of the above-mentioned small local energy community is economically viable, environmental friendly and socially accepted. Therefore it could be replicated in other territories with similar availability of renewable energies, increasing their energy autonomy and sustainability.

Creation of Zero CO2 Emissions School Buildings Due to Energy Use in Crete-Greece

Decrease of energy consumption in buildings and increase of the share of renewable energies in them are currently technologically and economically feasible and it is promoted by E.U. policies. After 2019, all the new public buildings in EU countries must be near zero energy buildings reducing their energy consumption and CO2 emissions. Use of various renewable energies for heat and power generation in school buildings in Crete-Greece can result in zeroing their fossil fuels consumption and CO2 emissions. Purpose of the current work is to investigate the possibilities of creating zero CO2 emissions school buildings in Crete-Greece due to operational energy use in them. A methodology which allows the replacement of fossil fuels with renewable energies in school buildings is proposed. Solar energy, solid biomass and low enthalpy geothermal energy, which are abundant in Crete, can be used for that. School buildings in Greece consume significantly less energy, 68 KWh/m2 year, and emit less CO2, 28 kgCO2/m2 year, than the corresponding buildings in other countries. The installation cost of renewable energies systems in order to replace all fossil fuels used in school buildings in Crete-Greece and to zero their CO2 consumption due to energy use in them has been estimated at 47.42 - 87.71 €/m2, which corresponds to 1.69 - 3.13 €/kg CO2 saved.

Possibilities of Creating Zero CO2 Emissions Olive Pomace Plants Due to Energy Use in Crete, Greece

Olive pomace plants process olive paste, a waste product of olive mills which produces crude olive kernel oil and olive kernel wood. Olive kernel wood has very good burning characteristics, high heat content, low cost and it is used as a renewable solid fuel replacing liquid fuel and heating oil. Part of the produced olive kernel wood is consumed inside the factory for heat generation and the rest is sold to heat consumers. It has been estimated that a typical olive pomace plant located in Crete, Greece consumes 42.86% of the produced olive kernel wood for its own heat generation, while the remaining 57.14% is sold to various heat consumers. 99.1% of the energy used in these plants is consumed for heating and the rest, 0.9%, for lighting and the operation of various electric devices. Olive pomace plants utilize a renewable solid fuel, which is carbon neutral, for the production of thermal energy. Therefore their CO2 emissions regarding energy utilization are due to electricity use. Installation of solar-PV panels in the plant could generate annually all the electricity needed for its operation. The current legal framework in Greece through net-metering allows the offsetting of grid electricity consumed in factories with PV electricity. The required capital cost of a solar-PV system installed in a typical olive pomace plant located in Crete, Greece in order to offset the grid electricity consumed annually has been estimated at 185,832€, the payback period of 5.33 years and the net present value at 555,671€. Since the plant could utilize only solid biomass for heat generation and could offset the grid electricity consumption with solar electricity, its total CO2 emissions due to energy use would be zero contributing positively to climate stabilization.

Potential of acoustic emissions from three point bending tests as rock failure precursors

Development of failure in brittle materials is associated with microcracks,which release energy in the form of elastic waves called acoustic emissions. This paper presents results from acoustic emission measurements obtained during three point bending tests on Nestos marble under laboratory conditions.Acoustic emission activity was monitored using piezoelectric acoustic emission sensors,and the potential for accurate prediction of rock damage based on acoustic emission data was investigated. Damage localization was determined based on acoustic emissions generated from the critically stressed region as scattered events at stresses below and close to the strength of the material.

Removal of Turbidity and COD from a Synthetic Water Sample by Coagulation

The main objective of this research was to study the removal of turbidity and COD （chemical oxygen demand） from a synthetic water sample. The water sample was treated chemically by coagulation. Two inorganic coagulants were used, ferric chloride and the double salt potassium-aluminium sulphate. The optimum coagulant dosage and working pH were examined. The results for ferric chloride as coagulant showed that the maximum removal efficiency （%） of COD was achieved at pH 6 with a dosage of 100 mg-L-1 and the maximum removal efficiency （%） of turbidity at pH 5 with a dosage of 500 mg.L-1. For double salt, as coagulant, the maximum removal efficiencies （%） of COD and turbidity were achieved at pH 6 with a dosage of 3,500 mg.L-1. An extensive comparison with results from previous studies was also described in this research.

A Study on the Degradation of Carbamazepine and Ibuprofen by TiO₂&ZnO Photocatalysis upon UV/Visible-Light Irradiation

The degradation of carbamazepine (CBZ) and ibuprofen (IBP) in aqueous matrices was investigated by TiO2 and ZnO photocatalysis initiated by UV-A and visible-light irradiation. Emphasis was given on the effect of operating parameters on the degradation effectiveness, such as catalyst type and loading (50 - 500 mg/L), initial drug concentration (10, 40, 80 mg/L) and wavelength of irradiation (200 - 600 nm). In an effort to understand the photocatalytic pathway for CBZ and IBP removal in terms of primary oxidants, the contribution of HO· was evaluated. With this scope, the radical-mediated process was suppressed by addition of an alcohol scavenger, isopropanol, (i-PrOH), described as the best free hydroxyl radical quencher. The photodegradation rate of the pharmaceuticals was monitored by high performance liquid chromatography (HPLC). According to the results, visible-light exposure, at λexc > 390 nm, takes place as a pure photocatalytic degradation reaction for both compounds. IBP was found to have overall high conversion rates, compared to CBZ. IBP oxidized fast under photocatalytic conditions, regardless the adverse effect of the increase of initial drug concentration, or low catalyst load, irradiation upon visible-light, by either titania or zinc oxide. Finally, addition of isopropanol showed a significant inhibition effect on the CBZ degradation, taken as an evidence of a solution-phase mechanism. In the case though of IBP degradation, the hole mechanism may be prevailing, suggested by the negligible effect upon addition of isopropanol indicating a direct electron transfer between holes (h+) and surface-bound IBP molecules. A plausible mechanism of IBP and CBZ photocatalysis was proposed and described.

Energy Savings in Municipal Road Lighting： The Case of the Municipality of Hersonissos

In an era governed by economic crisis, deep recession and lack of funds, the perspective of sustainable development drives local government to a more focused and constant effort to adapt to their daily requirements not only in respect to the central state but also towards the growing needs of the local society. As the need for planning actions in accordance with the principles of sustainable energy remains urgent, municipalities continue to envision and to respond to their role in helping to create a better future for generations to come. Thereupon the vision of the Municipality of Hersonissos, as firstly recorded in its Business Plan for 2011-2014, was, and still is, its＇ development in an Economic, Tourist and Cultural pole by adopting and applying the basic principles of sustainable development. At the same time the Municipality＇s rigid vision, planning, and evaluation, oriented by environmental protection, highlighted the need for networking on European level as although cities are different, their problems are often common. Thus on April 18, 2011, the Municipality of Hersonissos, joined the European Union initiative ＂Covenant of Mayors＂ [1] with the common aim of the fight against climate change. This article presents the significant initiatives taken in this direction in the last decade and their results not only on economical level but also along their social impact. It also aims to point out a municipality＇s vital role in knowledge and technology diffusion within the local society as sustainable energy development can be deployed not only by the private sector but also by the public.

Prevalence of Mild Cognitive Impairment in Individuals Aged over 65 in a Rural Area in North Greece

There are no data available on the prevalence of Mild Cognitive Impairment (MCI) in Greece, and the existing information about dementia shows important variations depending on the geographical setting as well as the methodology employed. The aim of this study was to determine the prevalence of MCI in individuals aged over 65 in a rural area in the north part of Greece. From 1428 residents, 678 were finally examined, with a mean age of 73.35 years. Assessments, including neuropsychological testing, neurological examination and medical history, were used to assign a diagnosis of normal cognition, mild cognitive impairment (MCI), with or without depression, depression or dementia according to suitable criteria. A questionnaire was also used to obtain social and demographic data. The 26.3% were classified as Mild Cognitive Impaired without depression, the 8.8% as Mild Cognitive Impaired due to depression, 5.9% had sole depression, the 2.4% were diagnosed with dementia and 56.6% had normal mental status. The observed prevalence for MCI with and without depression implies a total of 35.1% of all people aged over 65 with MCI in the study area. Mild cognitive impairment is more prevalent in Greece than dementia, and its subtypes vary in prevalence.

Production of a Mathematic Equation Using Statistical Data for the Determination of Kinematic Viscosity in Blends of Diesel Fuel with Biodiesel

In this paper, the authors try to export an equation which describes the variation of kinematic viscosity in blends of diesel fuel with biodiesel. Using specific volume of these blends, the authors determine kinematic viscosity via method ASTM D 445-06 using a capillary glass viscometer in order to study the contribution of quantity of biodiesel and convert the statistical data into mathematic relation as a specific formula, attempting to achieve an empirical evaluation. Trying to accomplish this, the authors studied the way how the values of variables are changed and whether a relation exists using dispersion diagrams. From the graphic depiction, the authors realized that the relation is linear and they proceeded to regression analysis. The analysis extracted the conclusion that the relation was strong and the values of the dependent variable kinematic viscosity was depended on a large percentage of the values of the mixture of fuels.

Specifying the Global Execution Context of Computer-Mediated Tasks: A Visual Notation and a Supporting Tool

This paper presents the notion of the global execution context of a task as a representational construct for analysing complexity in software evolution. Based on this notion a visual notation and a supporting tool are presented to support specification of a system’s global execution context. A system’s global execution context is conceived as an evolving network of use scenarios depicted by nodes and links designating semantic relationships between scenarios. A node represents either a base or a growth scenario. Directed links characterize the transition from one node to another by means of semantic scenario relationships. Each growth scenario is generated following a critique (or screening) of one or more base or reference scenarios. Subsequently, representative growth scenarios are compiled and consolidated in the global execution context graph. The paper describes the stages of this process, presents the tool designed to facilitate the construction of the global execution context graph and elaborates on recent practice and experience.

Possibility of Zeroing CO₂Emissions Due to Energy Use in Gavdos Island, Greece

The possibility of transforming Gavdos Island located south of Crete, Greece to a 100% renewable energies island has been investigated. Gavdos Island has few inhabitants but it hosts a large number of tourists during the summer. Due to the small size of the island the use of vehicles is limited. It has abundant local energy resources, mainly solar and wind energy, which are currently underutilized. Electricity is locally generated with diesel oil and its electric grid is not interconnected with the grid of Crete. Energy demand in the island has been estimated as well as the availability of various renewable energy resources. The most reliable and cost effective of them, including solar thermal, solar and wind power, solid biomass burning and high efficiency heat pumps have been indicated for achieving a 100% renewable island. Electric vehicles must also replace conventional vehicles in order to zero carbon emissions in transport. Since the power grid in the island is isolated, electricity storage is required and it could be obtained either with electric batteries or with a small hydro-pump storage system. The nominal power of the required solar-PV system for covering all the electricity needs in Gavdos island has been estimated at 848 KWp and the required electricity storage capacity was at 19.2 MWh.

Simulation and Modelling of Smart Beams with Robust Control Subjected to Wind Induced Vibration

This paper presents some recent developments in modelling and numerical analysis of piezoelectric systems and controlled smart structures based on a ?nite element formulation with embedded control. The control aims at vibration suppression of the structure subjected to external disturbances, like wind and noise, under the presence of model inaccuracies, using the available measurements and controls. A smart structure under dynamic loads is analysed and comparison between results for beam with and without control is made. The numerical results show that the control strategy is very effective and suppresses the vibrations of the structure.

Surfaces of Revolution in the General Theory of Relativity

We present a class of axially symmetric and stationary spaces foliated by a congruence of surfaces of revolution. The class of solutions considered is that of Carter’s family [A] of spaces and we try to find a solution to Einstein’s equations in the presence of a perfect fluid with heat flux. This approach is an attempt to find an interior solution that could be matched to a corresponding exterior solution across a surface of zero hydrostatic pressure. The presence of a congruence of surfaces of revolution, described as the quotient space of the commoving observers, can be useful to the determination of the surface of zero pressure. Finally we present two formal solutions representing ellipsoids of revolutions.

A New Method for Comparing Hospital and Municipal Wastewater

The objective of this study is to investigate the differences in organic compounds that are present in hospital and municipal wastewater samples. Two samples with the same COD （chemical oxygen demand） values were chosen for this study. The results have shown that both samples consist of the same compounds with low molecular weights and high polarities in high concentrations. The hospital wastewater consisted of more compounds arithmetically. Differences were found in the organic compound with low molecular weight and low polarities. Pharmaceutical compounds such as caffeine, acetanilide and phenacetin were detected only in the hospital wastewater.

Digital Dividend： The Path Towards Business and Marketing Development

Wireless radio spectrum is an important resource that allows for increased business development, throtigh the provision of services using wireless networking infrastructures. Since radio spectrum is limited, an optimal utilization of it is required, by adopting advanced spectrum management methods. The current transition from analogue to digital terrestrial television may act as a unique opportunity, in order to reallocate this valuable spectrum resource. After the transition, a part of the traditional analogue television spectrum bands will be completely released, allowing for the use of this spectrum by sophisticated wireless systems. Furthermore, digital terrestrial television interleaves spectrum bands in order to avoid possible interference between adjacent channels used by broadcasting stations, thus leaving spectrum holes exploited by novel wireless networks, namely unlicensed secondary systems. In this context, this article investigates business and marketing development issues, arising by utilizing released and interleaved television spectrum bands

Pain and Care： Interventions in Daily Nursing Practice

Pain is a common symptom in humans, which differs significantly depending on their status of health. This review lists the specific features of pain that are necessary for its evaluation and treatment by the health professionals. Extensive review of the recent literature was conducted in electronic databases （PubMed, Medline and Iatrotek） and scientific journals in Greek and English. Pain is perceived as any uncomfortable feeling, and emotional experience that occurs anywhere in the body when there is some kind of injury. The assessment of pain in humans is a complex and demanding process. Pain should be treated early with appropriate pharmaceutical or other treatment. Each pain has a different cause and treatment. The objective of health professionals＇ interventions is to cure or at least reduce pain and to relieve those who are in pain.

Environmental Sustainability and Regional Competitiveness:Innovative Steps by a Local Public Authority towards Energy Saving

Public local authorities are among the key players not only for assisting a nation to achieve its strategic energy goals but also for raising awareness towards relevant topics among its citizens.Yet,there has been little research on their role in this policy agenda.This paper aims to fill this gap by highlighting the significance of a local authority’s outcomes,in the environmental sustainability sphere,by its participation in various projects and EU programs.The reference years are 2014 to 2019 and the focus area is energy savings in public buildings and raising awareness on energy issues and sustainable development.This article’s aim is to outline the derived add value towards regional competitiveness and environmental sustainability from each action.Hersonisos Municipality’s holistic approach aims to reduce its overall energy balance and to point out that local authorities can become both a beckon of sustainability and a regional development pillar.

Biomarker-based diagnosis of cognitive disorders in a case series

The classical cerebrospinal fluid biomarkers of Alzheimer's Disease (namely total tau, phospho-tau and amyloid beta peptide) have received much attention, since they can detect the biochemical fingerprint of Alzheimer's disease and serve as a diagnostic aid for correct diagnosis of cognitive disorders during life. In this case series, we present 6 examples of patients with cognitive impairment of various types and severities and how biomarker data were helpful in every day diagnostic approach, combined with clinical, neuropsychological and imaging data and based on the most recent guidelines and recommendations.