Addition of two steel storeys on existing multi-storeys building

Εθνικό Μετσόβιο Πολυτεχνείο--Μεταπτυχιακή Εργασία. Διεπιστημονικό-Διατμηματικό Πρόγραμμα Μεταπτυχιακών Σπουδών (Δ.Π.Μ.Σ.) “Δομοστατικός Σχεδιασμός και Ανάλυση των Κατασκευών

Investigation of long - term movements in trigonometric network and on the crest of the dam / reservoir Evinos

167 σ.Εθνικό Μετσόβιο Πολυτεχνείο--Μεταπτυχιακή Εργασία. Διεπιστημονικό-Διατμηματικό Πρόγραμμα Μεταπτυχιακών Σπουδών (Δ.Π.Μ.Σ.) “Γεωπληροφορική”Αντικείμενο της εργασίας είναι η επαναμέτρηση, η επίλυση και ο έλεγχος μικρομετακινήσεων του βασικού γεωδαιτικού δικτύου του φράγματος Ευήνου καθώς και επιλεγμένων σημείων ελέγχου στη στέψη του φράγματος με τη χρήση του δορυφορικού συστήματος GPS. Επίσης συγκρίσεις γίνονται σε σχέση με τις επίγειες μετρήσεις της ΕΥΔΑΠ Α.Ε. για το διάστημα (1997 – 2011). Συγκεκριμένα, στην περιοχή του Αγ. Δημητρίου Ευήνου, (ορεινή Ναυπακτία, Νομός Αιτωλοακαρνανίας) έγινε συλλογή μετρήσεων GPS το διάστημα από 27/3/2011 έως 30/3/2011. Βασικός στόχος της εργασίας είναι, o έλεγχος των επιφανειακών μετακινήσεων στο τοπικό γεωδαιτικό δίκτυο και στη στέψη του φράγματος Ευήνου, με την χρήση του δορυφορικού συστήματος GPS, σε συγκεκριμένα σημεία (βάθρα ελέγχου) που έχουν τοποθετηθεί στην περιοχή και στη στέψη του φράγματος και σε περιοχές που παρουσιάζουν ενδείξεις μικρομετακίνησης (θέση αριστερού αντερείσματος στην περιοχή της κατολίσθησης του πρανούς το 1993). Παράλληλα, η παρούσα εργασία αποσκοπεί στη μελέτη της διαχρονικής παρακολούθησης των οριζόντιων και κατακόρυφων μετακινήσεων των σημείων ελέγχου της στέψης του φράγματος. Τα διαθέσιμα επίγεια γεωδαιτικά δεδομένα που δόθηκαν από την Διεύθυνση Υδροληψίας της Ε.ΥΔ.Α.Π. Α.Ε. αφορούν επιπρόσθετα τα ορθομετρικά υψόμετρα των σημείων ελέγχου που είναι εγκατεστημένα στη στέψη του φράγματος, για την ίδια χρονική περίοδο. Από την μελέτη των αποτελεσμάτων που έγινε σε κοινό τοποκεντρικό σύστημα αναφοράς για τα επίγεια και τα δορυφορικά δεδομένα GPS για τον έλεγχο μετακινήσεων των σημείων αναφοράς του γεωδαιτικού δικτύου του φράγματος δεν προκύπτουν ενδείξεις για επιφανειακή μετακίνηση. Γενική παρατήρηση για όλα τα σημεία ελέγχου της στέψης είναι, ότι κατά την τελική φάση κατασκευής του φράγματος (1998) και την αρχική πλήρωση του ταμιευτήρα (2001) οι μετακινήσεις ήταν μεγαλύτερες σε σχέση με τα τελευταία έτη λειτουργίας του (2009). Αυτή η συμπεριφορά του φράγματος θεωρείται φυσιολογική σε συνάρτηση με το χρόνο. Από τα αντίστοιχα διαγράμματα παρατηρείται η ομαλή εξέλιξη των καθιζήσεων των βάθρων ελέγχου της στέψης και υπάρχει μία σταθεροποίηση των καθιζήσεων κατά το πέρασμα του χρόνου. Επίσης γίνεται ανάλυση και σχολιασμός στα αποτελέσματα που αφορούν την φάση κατασκευής, τη φάση πλήρωσης και λειτουργίας.The scope of this Diploma Thesis is the remeasurement, computation and kinematic analysis of the geodetic control network of Evinos dam and of selective control points on the crest of the dam using the satellite system GPS, compared with ground measurements made by EYDAP SA for the period (1997 - 2011). Specifically, in St. Demetrios Evinos in the mountainous area of Nafpaktos (Prefecture of Aitoloakarnania) were collected GPS measurements for the period (27/03/2011 - 30/03/2011). The main objective of this survey is, the computation of surface movements on the local geodetic network and on the crest of the dam Evinos, using the satellite system GPS, to specific control points that have been placed around the dam and the crest of the dam and in areas with signs of movements (around the left abutment near the landslide of the slope in 1993). Also, this survey aims to study the structural analysis of horizontal and vertical displacement of the control points of the crest of the dam. The available terrestrial geodetic data supplied by Department of Water Supply of EYDAP S.A., also concern the orthometric elevations of control points that are established on the crest of the dam, for the same period. From the study of the results made in a topocentric reference system for terrestrial and satellite GPS data for controlling the control points of the geodetic network of the dam there are no indications of significant surface movement. As a general comment, all control points of the crest are, that in the final phase of construction of the dam (1998) and the initial filling of the reservoir (2001) the movement was greater than the last years of operation (2009). This behavior of the dam is considered to be normal. From the diagrams of displacement it appears a normal behaviour of the settlements of the control points of the crest, and there is a decrease of the settlements with time. Also, the thesis consideration, gives an analysis and comments to the results relating to the construction phase, the phase of filling and operation.Γεώργιος Δ. Αντωνακόπουλο

AdaGrad avoids saddle points

International audienceAdaptive first-order methods in optimization are prominent in machine learning and data science owing to their ability to automatically adapt to the landscape of the function being optimized. However, their convergence guarantees are typically stated in terms of vanishing gradient norms, which leaves open the issue of converging to undesirable saddle points (or even local maximizers). In this paper, we focus on the ADAGRAD family of algorithms-with scalar, diagonal or full-matrix preconditioning-and we examine the question of whether the method's trajectories avoid saddle points. A major challenge that arises here is that ADAGRAD's step-size (or, more accurately, the method's preconditioner) evolves over time in a filtration-dependent way, i.e., as a function of all gradients observed in earlier iterations; as a result, avoidance results for methods with a constant or vanishing step-size do not apply. We resolve this challenge by combining a series of step-size stabilization arguments with a recursive representation of the ADAGRAD preconditioner that allows us to employ stable manifold techniques and ultimately show that the induced trajectories avoid saddle points from almost any initial condition

Uroperitoneum after Caesarean Section

Intraoperative injuries of the bladder and the attendant vesicouterine and vesicovaginal fistulas formation are reported as rare events, but the rapid increase in the number of caesarean sections has contributed to the emergence of these complications. Early recognition of these complications makes them much easier to deal with, while simple measures intraoperatively can ensure that these complications will not escape attention. We present our rare case of uroperitoneum after cesarean section, the way of diagnosis and treatment, and due to this incident we review in detail the existing literature on the topic

AdaGrad avoids saddle points

International audienceAdaptive first-order methods in optimization are prominent in machine learning and data science owing to their ability to automatically adapt to the landscape of the function being optimized. However, their convergence guarantees are typically stated in terms of vanishing gradient norms, which leaves open the issue of converging to undesirable saddle points (or even local maximizers). In this paper, we focus on the ADAGRAD family of algorithms-with scalar, diagonal or full-matrix preconditioning-and we examine the question of whether the method's trajectories avoid saddle points. A major challenge that arises here is that ADAGRAD's step-size (or, more accurately, the method's preconditioner) evolves over time in a filtration-dependent way, i.e., as a function of all gradients observed in earlier iterations; as a result, avoidance results for methods with a constant or vanishing step-size do not apply. We resolve this challenge by combining a series of step-size stabilization arguments with a recursive representation of the ADAGRAD preconditioner that allows us to employ stable manifold techniques and ultimately show that the induced trajectories avoid saddle points from almost any initial condition

Perinatal Inflammation: Could Partial Blocking of Cell Adhesion Molecule Function Be a Solution?

In spite of the great advances made in recent years in prenatal and perinatal medicine, inflammation can still frequently result in injury to vital organs and often constitutes a major cause of morbidity. It is today well established that in neonates—though vulnerability to infection among neonates is triggered by functional impairments in leukocyte adhesion—the decreased expression of cell adhesion molecules also decreases the inflammatory response. It is also clear that the cell adhesion molecules, namely, the integrins, selectins, and the immunoglobulin (Ig) gene super family, all play a crucial role in the inflammatory cascade. Thus, by consolidating our knowledge concerning the actions of these vital cell adhesion molecules during the prenatal period as well as regarding the genetic deficiencies of these molecules, notably leukocyte adhesion deficiency (LAD) I, II, and III, which can provoke severe clinical symptoms throughout the first year of life, it is anticipated that intervention involving blocking the function of cell adhesion molecules in neonatal leukocytes has the potential to constitute an effective therapeutic approach for inflammation. A promising perspective is the potential use of antibody therapy in preterm and term infants with perinatal inflammation and infection focusing on cases in which LAD is involved, while a further important scientific advance related to this issue could be the combination of small peptides aimed at the inhibition of cellular adhesion

Increased Fibroblast Growth Factor 21 (FGF21) Concentration in Early Second Trimester Amniotic Fluid and Its Association with Fetal Growth

Altered fetal growth, either reduced or exacerbated, is associated with adverse perinatal outcomes. The underlying pathogenetic mechanisms of altered growth remain unclear. Fibroblast growth factor 21 (FGF21) and insulin are both considered to be major regulators of tissue growth and metabolism. The aim of our study was to investigate the association of second trimester amniotic fluid FGF21 and insulin concentrations with fetal growth. The amniotic fluid concentrations of FGF21 and insulin were determined in 80 cases of different fetal growth patterns (SGA—small for gestational age, LGA—large for gestational age, and AGA—appropriate for gestational age fetuses). Both peptides were found to be increased in cases of abnormal fetal growth, reduced growth velocity (SGA), or macrosomia (LGA). Specifically, FGF21 was significantly increased, as higher FGF21 levels were observed in the amniotic fluid of SGA and LGA fetuses compared with AGA fetuses (p < 0.05). Furthermore, the more severe the fetal smallness, the higher the FGF21 levels (p < 0.05). Similarly, higher insulin levels were noted in the amniotic fluid of SGA and LGA fetuses compared with those in AGA fetuses, though this was not statistically significant (p > 0.05). Again, the more severe the reduced fetal growth, the higher the insulin levels

Detection and Quantification of Neurotrophin-3 (NT-3) and Nerve Growth Factor (NGF) Levels in Early Second Trimester Amniotic Fluid: Investigation into a Possible Correlation with Abnormal Fetal Growth Velocity Patterns

Background: Abnormal fetal growth is associated with adverse perinatal and long-term outcomes. The pathophysiological mechanisms underlying these conditions are still to be clarified. Nerve growth factor (NGF) and neurotrophin-3 (NT-3) are two neurotrophins that are mainly involved in the neuroprotection process, namely promotion of growth and differentiation, maintenance, and survival of neurons. During pregnancy, they have been correlated with placental development and fetal growth. In this study, we aimed to determine the early 2nd trimester amniotic fluid levels of NGF and NT-3 and to investigate their association with fetal growth. Methods: This is a prospective observational study. A total of 51 amniotic fluid samples were collected from women undergoing amniocentesis early in the second trimester and were stored at −80 °C. Pregnancies were followed up until delivery and birth weight was recorded. Based on birth weight, the amniotic fluid samples were divided into three groups: appropriate for gestational age (AGA), small for gestational age (SGA), and large for gestational age (LGA). NGF and NT-3 levels were determined by using Elisa kits. Results: NGF concentrations were similar between the studied groups; median values were 10.15 pg/mL, 10.15 pg/mL, and 9.14 pg/mL in SGA, LGA, and AGA fetuses, respectively. Regarding NT-3, a trend was observed towards increased NT-3 levels as fetal growth velocity decreased; median concentrations were 11.87 pg/mL, 15.9 pg/mL, and 23.5 pg/mL in SGA, AGA, and LGA fetuses, respectively, although the differences among the three groups were not statistically significant. Conclusions: Our findings suggest that fetal growth disturbances do not induce increased or decreased production of NGF and NT-3 in early second trimester amniotic fluid. The trend observed towards increased NT-3 levels as fetal growth velocity decreased shows that there may be a compensatory mechanism in place that operates in conjunction with the brain-sparing effect. Further associations between these two neurotrophins and fetal growth disturbances are discussed