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This research further expands Graphic Statics and Graphic Kinematics methods that focus on moment-resisting structures such as frames and beams. With the use of Vector Algebra, the main method presented here, the Gamma Superimposition Assembly method, establishes a certain design-and-analysis framework for moment-resisting structures with the definition of load paths by the designer. The procedure presumes a particular architectural hypothesis. A brief historiographical narrative of the main contributions in the field of Graphic Statics is given together with a closer review of the contributions made since the re-emergence of the field more recently. Additions made by the author and others present the three main research axes to be followed: kinematics, frames, and topology investigation. Graph Theory and design parameters are introduced to decompose structural frames and lines of action of imposed forces in to sets of overlapping loops. The establishment of a strategy based on load path selection for representing a structure and its loads with a set of loops is argued. These loops will allow for an intuitive understanding of moments. The key method of this research is then introduced, the Gamma Superimposition Assembly method and its key feature, the Gamma loop is presented for the visualization of moments. These moments then take the form of bending and torsion with projections following Vector Algebra principles. An original method for drawing torsion is shown. The summation of loops generates a final diagram that informs the design in terms of structural members properties, such as suggested thicknesses and/or boundary conditions. This research suggests that support types can be the result of the method, rather than initially defined. Force distribution among different loops is then discussed in order to optimize maximum bending moments and make the structure more efficient. An example of a grillage structure where all implications are taken into account is developed. A simple example of applying the method to a more avant-garde architecture geometry is given. In kinematics, the Gamma Superimposition Assembly method is integrated within the conjugated beam method and with the visual explanation of the principle of Virtual Work with examples of applying non-parallel forces on parallel planes. Volumetric shapes constructed with the use of vector products represent the virtual and the real internal and external work and deflections and bending moment diagrams are used to show deformation angles. Extensions of Maxwell���s Load Path Theorem are presented in the context of 3D frames and examples are given on how to choose different load paths. Topology optimization and geometry design based on load paths are elaborated and conclude with the introduction of the Steiner Tree as a potential topology for structural morphologies with efficient load paths. The research finishes with a synopsis, conclusions, and a projection of the developed methods onto the realm of architectural and structural engineering applications and education today.

Πρόσφατα, η έρευνα στα δυναμικά κοινωνικά δίκτυα έχει αυξηθεί λόγω των πολυάριθμων δεδομένων που έχουν γίνει διαθέσιμα για εξερεύνηση. Πολλοί ερευνητές έχουν αρχίσει να εστιάζουν στη πρόβλεψη γεγονότων τα οποία χαρακτηρίζουν την εξέλιξη των κοινοτήτων στο χρόνο. Η πρόβλεψη της εξέλιξης των κοινοτήτων είναι ένα ενδιαφέρον πεδίο αφού μπορεί να συνεισφέρει στην εμπόδιση του ρατσισμού, της βίας και της τρομοκρατίας, στην αποκάλυψη νέων τάσεων και στην διάδοση πληροφοριών που κινδυνεύουν να χαθούν. Σε αυτή τη πτυχιακή εργασία προσπαθούμε να προβλέψουμε την εξέλιξη των κοινοτήτων σε ένα δυναμικό κοινωνικό δίκτυο. Για την πρόβλεψη χρησιμοποιούμε το OLED, μια ακολουθιακή και επαγωγική λογικού προγραμματισμού μέθοδο. Το OLED παράγει μια θεωρία η οποία μας δηλώνει πότε ένα εξελικτικό γεγονός αρχίζει και πότε τελειώνει να συμβαίνει. Έχουμε υιοθετήσει τα ακόλουθα εξελικτικά γεγονότα στην εργασία μας: Αύξηση, Συρρίκνωση, Συνέχιση, και Διάλυση. Σαν χαρακτηριστικά χρησιμοποιούμε τα δομικά χαρακτηριστικά κάθε κοινότητας και τις προηγούμενες καταστάσεις αυτής της κοινότητας (χρονικά χαρακτηριστικά). Τα πειράματα εκτελέστηκαν με πραγματικά δεδομένα από το Mathematics StackExchange. Δοκιμάσαμε και αξιολογήσαμε διάφορες ρυθμίσεις παραμέτρων στο OLED, ενώ επίσης επιτρέψαμε την κατασκευή δύο τύπων κανόνων. Αυτούς που λαμβάνουν υπόψιν τους μόνο την τρέχουσα χρονική στιγμή και του άλλους που περιλαμβάνουν στοιχεία από προηγούμενες χρονικές στιγμές στο σώμα τους. Τελικά παρουσιάζουμε ποια χαρακτηριστικά συμμετέχουν στην πρόβλεψη κάθε εξελικτικού γεγονότος και ποια από αυτά είναι άσχετα με αυτή τη πρόβλεψη. Recently, research on dynamic social network analysis has risen because of numerous data have been available for investigation. Many researchers have started focusing on predicting events that characterize the evolution of communities over time. Community evolution prediction is an interesting field, since it can contribute to prevention of racism, violence and terrorism, revelation new trends and salvage of information that is in danger to be lost. In this thesis, we try to predict the evolution of communities in a dynamic social network. For this prediction we use OLED, an Online Inductive Logic Programming method. OLED derives a theory which indicates us when an evolutionary event starts and when it stops to happen. We have adopted the following four evolutionary events in our work: Growth, Shrinkage, Continuation and Dissolution. As features we use the structural characteristics (structural features) of each community and the previous states of this community in time (temporal features). The experiments were executed with real life data from Mathematics StackExchange. We tried and evaluated various parameters settings on OLED, while also we permitted the construction two types of rules. These ones that considers only current time and the other which include elements from previous time in their bodies. Finally, we present which features participate in prediction of each evolutionary event and which of them are unrelated with this prediction.

The reaction of 2,5-bis[N,N′-bis(2-pyridyl-aminomethyl)aminomethyl]-p-hydroquinone (H2bpymah) with VO2+ salts in acetonitrile or water at a low pH (2.2-3.5) results in the isolation of [{VIV(O)(Cl)}2(μ-bpymah)], the p-semiquinonate complex [{VIV(O)(Cl)}2(μ-bpymas)](OH), the cyclic mixed-valent hexanuclear compound [{VV(O)(μ-O)VIV(O)}(μ-bpymah)]3, and [(VVO2)2(μ-bpymah)]. [{VIV(O)(Cl)}2(μ-bpymas)](OH) is an intermediate of the radical-mediated oxidation of [{VIV(O)(Cl)}2(μ-bpymah)] from O2. At lower pH values (2.2), a reversible intramolecular electron transfer from the metal to the ligand of [{VIV(O)(Cl)}2(μ-bpymas)](OH) is induced with the concurrent substitution of chlorine atoms by the oxygen-bridging atoms, resulting in the formation of [{VV(O)(μ-O)VIV(O)}(μ-bpymah)]3. The metal complexes were fully characterized by X-ray crystallography, infrared (IR) spectroscopy, and magnetic measurements in the solid state, as well as by conductivity measurements, UV-vis spectroscopy, and electrochemical measurements in solution. The oxidation states of the metal ions and ligands were determined by the crystallographic data. The [{VIV(O)(Cl)}2(μ-bpymah)]-[{VIV(O)(Cl)}2(μ-bpymas)](OH) redox process is electrochemically reversible. The VIV ion in the semiquinonate compound exhibits a surprisingly low oxophilicity, resulting in the stabilization of OH- counterions at acidic pH values. An investigation of the mechanism of this reaction reveals that these complexes induce the reduction of O2 to H2O2, mimicking the activity of enzymes incorporating two redox-active centers (metal-organic) in the active site. © 2015 American Chemical Society. 54 15 7218 7229 Cited By :7

In this paper we study the suitability and performance of conventional time delay of arrival estimation for humanoid robots. Moving away from simulated environments, we look at the influence of real-world robot's shape on the sound source localization. We present a TDOA/GCC based sound source localization method that successfully addresses this influence by utilizing a pre-measured set of TDOAs. The measuring methodology and important aspects of the implementation are thoroughly presented. Finally, an evaluation is made with the humanoid robot Nao. The experimental results are presented and discussed.

Single molecule magnets are of great interest due to a multitude of potential applications for some of which thin films are required. Traditional physical vapor deposition techniques are not suitable for the deposition of these fragile materials with low decomposition temperatures. Matrix Assisted Pulsed Laser Evaporation technique has been employed for the growth of thin films of the single molecule magnet Mn 12(Propionate) on Si and glass substrates. In this paper we report on the appropriate growth conditions and also the morphology, chemical composition and magnetic behavior of the films. Continuous Mn 12(Propionate) films with properties similar to bulk materials have been obtained. © 2011 Elsevier B.V. 258 23 9471 9474 Cited By :1

We report on the successful implementation of Matrix Assisted Pulsed Laser Evaporation, to obtain films of the single molecule magnet Mn12 benzoate on Si substrates. The films have been characterized by optical microscopy, FTIR spectroscopy and extraction magnetometry. The results indicate that this deposition technique allows the fabrication of Mn12 benzoate films which are continuous and show magnetic properties similar to those of the parent molecular material. 12 3 557 560 Cited By :4