Classical quantum mechanics – particle is the pulse of matter waves

Since the very first development of Quantum Mechanics there are many scientists who, despite the fact that everything seems to work perfectly and the experimental results verify the theoretical predictions, do not understand what is really going on. That is why there are many different interpretations of this subject nowadays. This paper provides a new interpretation, aiming to illustrate the fact that Quantum Mechanics is actually an extension of Classical Physics, and in contrast to other interpretations we illustrate a possible experimental verification of theoretical wording

Perturbative QCD studies of multijet structures in electron-positron annihilation

To investigate the effect in perturbative QCD of multigluon emissions on the transverse momentum distributions of multijet final states in electron-positron annihilation, we use a simplified model based on the approximation that gluons are emitted independently. As a guide to these multigluon emissions, we study the two-gluon contribution in some detail and calculate the Q(_T)-distribution for four-jet events in e(^+)e̅(^-)annihilation, using suitable jet-defining cuts, needed both theoretically, to regularize the soft- and collinear-gluon singularities, as well as experimentally, to group the final-state particles into distinct jets. To ascertain the accuracy of our approximate model, we compare our results with the exact ones, obtained by a Monte Carlo generation of events using the full matrix elements. We find that, for realistic values of the cuts, there is a significant kinematic region of agreement. This agreement and the validity of our model are further elaborated by taking its Abelian QCD limit, calculating distributions in other event shape variables and studying the jet broadening phenomenon. The applicability of our model is also delineated by finding it to be in remarkable structural and numerical agreement with the more exact algorithm of Altarelli et al. Finally, to investigate the effect of higher order and virtual graphs corrections to low order tree-level results, we use our model to calculate the O(a(^2)(_s)) Or-distribution for three-jet events in e(^+)e(^-) annihilation with virtual contributions included. We study the dependence of these corrections on the resolution parameters used to perform the (analytic) cancellation of infrared and collinear singularities between real and virtual graphs and discuss their physical consequences

The Greek language of the diaspora in the era of globalisation

This paper is divided into two parts. The first one deals with the Greek language and education in the United States, focusing on schools, books, teachers and the educational policy of the Greek Orthodox Archdiocese and the Greek Government regarding this subject. For comparative purposes a brief portion of this section deals with the teaching of the Greek language and culture in Canada, Australia, Germany, and other countries. The second part focuses on the global aspects of the Greek language. It discusses the effects of the fall of Communism and the full membership of Greece in the EU and how these factors affected the Greek language and Government policy, regarding the funding of Greek Education globally. Finally, the paper offers some recommendations for maximising the benefits arising from this new world of globalisation

Congestion and medium access control in 6LoWPAN WSN

In computer networks, congestion is a condition in which one or more egressinterfaces are offered more packets than are forwarded at any given instant [1]. In wireless sensor networks, congestion can cause a number of problems including packet loss, lower throughput and poor energy efficiency. These problems can potentially result in a reduced deployment lifetime and underperforming applications. Moreover, idle radio listening is a major source of energy consumption therefore low-power wireless devices must keep their radio transceivers off to maximise their battery lifetime. In order to minimise energy consumption and thus maximise the lifetime of wireless sensor networks, the research community has made significant efforts towards power saving medium access control protocols with Radio Duty Cycling. However, careful study of previous work reveals that radio duty cycle schemes are often neglected during the design and evaluation of congestion control algorithms. This thesis argues that the presence (or lack) of radio duty cycle can drastically influence the performance of congestion control mechanisms. To investigate if previous findings regarding congestion control are still applicable in IPv6 over low power wireless personal area and duty cycling networks; some of the most commonly used congestion detection algorithms are evaluated through simulations. The research aims to develop duty cycle aware congestion control schemes for IPv6 over low power wireless personal area networks. The proposed schemes must be able to maximise the networks goodput, while minimising packet loss, energy consumption and packet delay. Two congestion control schemes, namely DCCC6 (Duty Cycle-Aware Congestion Control for 6LoWPAN Networks) and CADC (Congestion Aware Duty Cycle MAC) are proposed to realise this claim. DCCC6 performs congestion detection based on a dynamic buffer. When congestion occurs, parent nodes will inform the nodes contributing to congestion and rates will be readjusted based on a new rate adaptation scheme aiming for local fairness. The child notification procedure is decided by DCCC6 and will be different when the network is duty cycling. When the network is duty cycling the child notification will be made through unicast frames. On the contrary broadcast frames will be used for congestion notification when the network is not duty cycling. Simulation and test-bed experiments have shown that DCCC6 achieved higher goodput and lower packet loss than previous works. Moreover, simulations show that DCCC6 maintained low energy consumption, with average delay times while it achieved a high degree of fairness. CADC, uses a new mechanism for duty cycle adaptation that reacts quickly to changing traffic loads and patterns. CADC is the first dynamic duty cycle pro- tocol implemented in Contiki Operating system (OS) as well as one of the first schemes designed based on the arbitrary traffic characteristics of IPv6 wireless sensor networks. Furthermore, CADC is designed as a stand alone medium access control scheme and thus it can easily be transfered to any wireless sensor network architecture. Additionally, CADC does not require any time synchronisation algorithms to operate at the nodes and does not use any additional packets for the exchange of information between the nodes (For example no overhead). In this research, 10000 simulation experiments and 700 test-bed experiments have been conducted for the evaluation of CADC. These experiments demonstrate that CADC can successfully adapt its cycle based on traffic patterns in every traffic scenario. Moreover, CADC consistently achieved the lowest energy consumption, very low packet delay times and packet loss, while its goodput performance was better than other dynamic duty cycle protocols and similar to the highest goodput observed among static duty cycle configurations

Characterization and causes of the building stone decay at the Artemis temple, Brauron, E. Attica, Greece

Στην περιοχή της Βραβρώνας ή Βραώνας στην Α. Αττική σε μικρή απόσταση από τον ομώνυμο κόλπο, δίπλα στις όχθες του Ερασινού ποταμού υπάρχει ο ναός της Αρτέμιδας του 415 π.Χ. Οι δομικοί λίθοι που χρησιμοποιήθηκαν για την κατασκευή του ναού είναι ψαμμίτες και προέρχονται από Νεογενείς ιζηματογενείς αποθέσεις. Ιχνη από τα αρχαία λατομεία σε απόσταση 500μ. από τον ναό είναι ακόμη ορατά. Τα ερείπια του ναού είχαν μείνει θαμένα στην λάσπη του δέλτα του Ερασινού που σχημάτιζε σύστημα ελών και /αμνόθάλασσας, για δεκάδες αιώνων. Κατά τις εργασίες την αναστήλωσης, εκτός από τους θαμένους λίθους χρησιμοποιήθηκε και νέο υλικό από τους σχηματισμούς των αρχαίων λατομείων. Τα αναστηλωμένα τμήματα εμφανίζουν έντονα σημάδια διάβρωσης. Ο σκοπός αυτής της εργασίας είναι η μελέτη των μορφών και των αιτίων της διάβρωσης. Οι διαβρωσιγενείς μορφές οφείλονται σε ενδογενείς και περιβαλλοντολογικούς παράγοντες. Οι κυριότεροι ενδογενείς παράγοντες είναι α) το υψηλό πορώδες, και η κατανομή των πόρων, β) το ασβεστιτικό συνδετικό υλικό του λίθου γ) η ορυκτολογική σύσταση και κυρίως η παρουσία διασταλτών αργιλικών ορυκτών. Οι κυριότεροι περιβαλλοντολογικοί παράγοντες διάβρωσης που συντελούν στην ανακρυστάλλωση του ασβεστίτη και στη κρυστάλλωση αλάτων, είναι α) η παραμονή των δομικών λίθων ενταφιασμένων σε υφάλμυρο περιβάλλον, για αιώνες, β) τα συχνά πλημμυρικά επεισόδια και η πιθανή μόλυνση του ποταμού Ερασινού, γ) η επίδραση της όξινης βροχής και των θαλάσσιων ανέμων και δ) η βιοδιάβρωση. Τα συμπεράσματα αυτής της μελέτης μπορεί να έχουν εφαρμογή και σε άλλα ιστορικά μνημεία σε αντίστοιχα περιβάλλοντα.At Brauron (Vraona or Vravrona) area, E. Attica, near the Brauron bay, by the Erasinos river there is an ancient monument of 415 B.C., dedicated to Artemis. The building material used for the construction of the monument is sandstone originated from Neogene sedimentary deposits. The ancient quarries are located 500m away from the monument and traces of quarring are still visible. Monument ruins had been buried under the mud load curried by Erasinos river for many centuries. During the restoration works of the Temple of Artemis besides the stone found in situ, new material provided by the same formation was as well, used. The restored monument stones display intensive deterioration. The purpose of this paper is to study of the decay forms and investigate the decay causes of the building stone in the monument. The decay forms result from intrinsic (endogenic) and environmental factors. The main endogenic factors of decay of the sandstone used as building material, are: a) the high porosity, and the pore size distribution, b) the calcite cement of the stone c) the mineralogical composition, especially the presence of swelling clay minerals. The main environmental factors of decay that result to the calcite and salt crystallization are a) the burial of the ancient building stones, in the brackish water-mud, for centuries b) the frequent floods and possible pollution of the nearby Erasinos river c) the acid rain and aerosol attack d) the bioteterioration. The conclusions of this case study may have application on other monuments of historical interest, in similar environmen

Fluid-Solid Coupled Simulation of Hypervelocity Impact and Plasma Formation

The generation of plasma from hypervelocity impacts is an active research topic due to its important science and engineering ramifications in various applications. Previous studies have mainly focused on the ionization of the solid materials that constitute the projectile and the target. In this letter, we consider impact events that occur in a fluid (e.g.,~gas) medium, and present a multiphysics computational modeling approach and associated analysis to predict the behavior of the dynamic fluid-solid interaction that causes the surrounding fluid to ionize. The proposed computational framework is applied to a specific case involving a system of three interacting domains: a copper rod projectile impacting onto a soda lime glass target in a neon gas environment. The impact velocity is varied between 3 km/s and 6 km/s in different simulations. The computational model couples the compressible inviscid Navier-Stokes equations with the Saha ionization equations. The three material interfaces formed among the projectile, the target, and the ambient gas are tracked implicitly by solving two level set equations that share the same velocity field. The mass, momentum, and energy fluxes across the interfaces are computed using the FInite Volume method with Exact two-material Riemann problems (FIVER). The simulation result reveals a region of neon gas with high velocity, temperature, pressure, and mass density, formed in the early stage of the impact mainly due to the hypersonic compression of the fluid between the projectile and the target. For impact velocities higher than 4 km/s, ionization is predicted in this region

Analytical modelling of congestion for 6LoWPAN networks

The IPv6 over Low-Power Wireless Personal Area Network (6LoWPAN) protocol stack is a key part of the Internet of Things (IoT) where the 6LoWPAN motes will account for the majority of the IoT ‘things’. In 6LoWPAN networks, heavy network traffic causes congestion which significantly affects the overall performance and the quality of service metrics. In this paper, a new analytical model of congestion for 6LoWPAN networks is proposed using Markov chain and queuing theory. The derived model calculates the buffer loss probability and the channel loss probability as well as the number of received packets at the final destination in the presence of congestion. Also, we calculate the actual wireless channel capacity of IEEE 802.15.4 with and without collisions based on Contiki OS implementation. The validation of the proposed model is performed with different scenarios through simulation by using Contiki OS and Cooja simulator. Simulation results show that the analytical modelling of congestion has an accurate agreement with simulation

Thoughts on two approaches for accounting for the scatter in fatigue delamination growth curves

This paper discusses two approaches that have been proposed to account for the data scatter observed in delamination growth tests under cyclic-fatigue loading and thereby enable an estimate of a worst-case delamination growth curve for use in the damage tolerance and durability assessment of composite and adhesively-bonded airframes. The two approaches discussed are: (a) the normalisation approach, whereby the energy release rate is divided by the resistance to delamination growth, GR(a), and (b) the Hartman-Schijve approach to delamination growth. It is shown that for the cases considered this normalisation approach can be used to yield curves that are similar to the ‘mean-3σ’, “worst-case”, i.e. upper-bound, curve obtained using the Hartman-Schijve equation. However, despite the reduction in the scatter that arises if this particular normalisation approach is adopted, there is still considerable scatter in the important “near-threshold” region. In this region the normalised curves are bounded above by the ‘mean-3σ’ curve obtained using the Hartman-Schijve equation. To address this issue, an alternative normalisation approach is then proposed. This alternative normalisation approach has the advantage of having reduced scatter in the near-threshold region but elsewhere is significantly more conservative than the Hartman-Schijve approach

Transfers to psychiatry through the consultation-liaison psychiatry service: 11 years of experience

BACKGROUND: There are only a few reports on issues related to patient transfer from medical and surgical departments to the psychiatric ward by the consultation-liaison psychiatry service, although it is a common practice. Here, we present a study assessing the factors that influence such transfers. METHOD: We examined the demographic and clinical backgrounds of a group of patients transferred from internal medicine and surgery to the psychiatric ward over an 11-year period. A comparison was made of this data with data obtained from a group of non-transferred patients, also seen by the same consultation-liaison psychiatry service. RESULTS: According to our findings, the typical transferred patient, either female or male, is single, divorced or widowed, lives alone, belongs to a lower socioeconomic class, presents initially with (on the whole) a disturbed and disruptive behaviour, has had a recent suicide attempt with persistent suicidal ideas, suffers from a mood disorder (mainly depressive and dysthymic disorders), has a prior psychiatric history as well as a prior psychiatric inpatient treatment, and a positive diagnosis on axis II of the five axis system used for mental health diagnosis. CONCLUSION: The transfer of a patient to the psychiatric ward is a decision depending on multiple factors. Medical diagnoses do not seem to play a major role in the transfer to the psychiatric ward. From the psychiatric diagnosis, depressive and dysthymic disorders are the most common in the transferred population, whilst the transfer is influenced by social factors regarding the patient, the patient's behaviour, the conditions in the ward she/he is treated in and any recent occurrence(s) that increase the anxiety of the staff