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Η εξοικονόμηση ενέργειας σε ένα κτίριο μέσω της αποτελεσματικής χρήσης του κτιριακού αυτοματισμού και των ενεργειακών βελτιώσεων που πρέπει να γίνουν σε αυτό είναι δυο τομείς που συγκεντρώνουν μεγάλο ενδιαφέρον τα τελευταία χρόνια. Ειδικά αν η προσπάθεια αυτή συνδυαστεί με τη χρήση μεθόδων της Ασαφούς Λογικής και των Ασαφών Γνωστικών Δικτύων (ΑΓΔ) τότε αναμένουμε πολλά και αξιόλογα αποτελέσματα τα οποία υπόσχονται μια ραγδαία βελτίωση του τρόπου ζωής μας. Στόχος της παρούσας διπλωματικής εργασίας είναι να χρησιμοποιούν προηγμένες θεωρίες ελέγχου για να διαμορφωθεί τη συνολική ενεργειακή συμπεριφορά ενός κτιρίου για οικιστική ή εμπορική χρήση. Η προτεινόμενη μέθοδος είναι η χρήση ασαφούς λογικής και ο έξυπνος έλεγχος για να διαμορφωθούν τέτοια έξυπνα κτίρια. Για το σκοπό αυτό κατασκευάζονται ένα σύστημα Ασαφούς Λογικής και ένα Ασαφές Γνωστικό Δίκτυο και μελετώνται οι ενεργειακές απαιτήσεις ενός κτιρίου από το νότιο τμήμα της Ελλάδας. Το προτεινόμενο έξυπνο λογισμικό που διαμορφώνεται αποτελείται από δύο μέρη: Α) Το Ασαφές Σύστημα Συμπερασμού, το οποίο λαμβάνοντας υπόψη τα μετεωρολογικά δεδομένα της περιοχής (ηλιακή ακτινοβολία, θερμοκρασία κλπ) ελέγχει τον αυτοματισμό του κτιρίου (HVAC και φωτισμός), προκειμένου να επιτευχθεί πιο αποτελεσματική χρήση του. Β) Το Ασαφές Γνωστικό Δίκτυο (ΑΓΔ), το οποίο βάσει της χρήσης του κάθε στοιχείου του αυτοματισμού κτιρίου, ανιχνεύει αν το κτίριο χρειάζεται ενεργειακές βελτιώσεις και εάν ναι, προτείνει τις κατάλληλες λύσεις με βάση την κατανάλωση ενέργειας. Οι μελέτες προσομοίωσης διεξήχθησαν χρησιμοποιώντας και τις δύο μεθόδους. Τα ληφθέντα αποτελέσματα έδειξαν ότι και οι δύο μέθοδοι μπορούν να συνεισφέρουν θετικά στη βελτίωση του αυτοματισμού κτιρίων, καθώς και στη συνολική ενεργειακή συμπεριφορά του κτιρίου. / Reducing the energy consumption of a building through the effective use of its automation and the necessary energy improvements that can be made, are two scientific areas that gathered a lot of interest in recent years, especially, if this effort is combined with the use of advanced system and control theories such as fuzzy logic, intelligent control and Fuzzy Cognitive Maps (FCM). The purpose of this diploma thesis is to use advanced control theories to model the total energy behavior of an autonomous building for residential or commercial use. The proposed method is using fuzzy logic and intelligent control to model such intelligent buildings. A Fuzzy Logic and a Fuzzy Cognitive Map are constructed. The energy requirements for a building from the southern part of Greece are determined using the Design Builder software. The proposed intelligent software tool is composed of two parts: A)The Fuzzy Inference System (FIS) which taking into account the weather data of the area (sun radiation, temperature etc.) controls the building automation (HVAC and lighting) in order to achieve its most effective use. Β)The Fuzzy Cognitive Map (FCM) which based on the use of each element of the building automation, detects whether the building needs energy improvements and if so, proposes appropriate solutions based on its energy consumption. Simulation studies were conducted using both methods. The obtained results have shown that both methods can contribute positively to the improvement of the building automation as well to the overall energy behavior of the building.

Efficient control is often the most cost-effective option to improve on the running cost of a Three-Pipe Water Pumping System. However, the effect of changing the control strategy (i.e. on energy consumption) is usually difficult to predict. To obtain this information more easily, a new simulation tool, QUICKcontrol, was developed. This new tool was used to investigate the energy cost savings potential in a Three-Pipe Water Pumping System. The influence of pump scheduling, dam level set points, control parameters and different combinations thereof was investigated. The simulation models were firstly verified with measurements obtained from the existing system to confirm their accuracy for realistic control retrofit simulations. With the aid of the integrated simulation tool it was possible to predict savings of R 195'000 per year with an average 3.8 MW of load shifted. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2005.

This dissertation addresses three issues in international macroeconomics. The first chapter examines optimal portfolio decisions in a monetary open economy DSGE model. In a complete market environment, Engel and Matsumoto (2005) find that sticky price can generate equity home bias. However, their result is sensitive to the structure of the financial market. In an incomplete market environment, we find “super home bias” in the equilibrium equity portfolio, which casts doubt on the ability of sticky price in describing the observed equity portfolios. We further show that introducing sticky wages helps to match the data. The second chapter analyzes the welfare impact of financial integration in a standard monetary open-economy model. Financial integration may have negative effects on welfare if integration occurs in the presence of nominal price rigidities and constraints on the efficient use of monetary policy. The reason is that financial integration leads to excessive terms of trade volatilities. From a policy perspective, the model implies that developing economies that are experiencing financial integration may attempt to alleviate the welfare cost of integration by stabilizing the exchange rate. This prediction is consistent with the widespread reluctance to following freely floating exchange rates among these economies. On the other hand, for advanced economies that have the ability to operate efficient inflation targeting monetary policies, financial integration is always beneficial. Thus, the model accounts for the observed acceleration in cross-border asset trade among advanced economies in the early 1990s as it was mainly the industrial countries that switched to an inflation targeting regime at the time. The third chapter uses an open-economy neoclassical growth model to explain the saving and investment behavior of the U.S. and a group of other OECD countries. We find that while the model explains investment quite well, it tends to overpredict U.S saving and underpredict saving in the rest of the world. We show that the closed-economy version of the model also predicts saving accurately but that is only because it imposes equality between saving and investment. In effect, the model explains investment not saving behavior.

This thesis consists of three essays. In Precautionary Saving under Correlated Risk, I show that the sign of the correlation between the random variables might determine whether saving increases or decreases when risk is introduced. Precautionary saving is thus not confirmed. In the second part of this chapter, the consumer must also allocate her saving between an insurance and an interest-bearing asset. It is shown that switching the sign of correlation changes the optimal insurance ratio and probably also optimal saving. Saving and Portfolio Choice by Mutually Altruistic Consumers treats the effects of mutual altruism between two individuals. Compared to the Utilitarian social optimum there is, on the one hand, a tendency to higher saving and lower risk share resulting from the higher uncertainty of future income in the Nash equilibrium. On the other hand, there is a tendency to lower saving and higher risk share arising from the possibility of a free ride on the generosity of others, named "Samaritan's Dilemma". Analytically, it was not possible to determine the size or the direction of divergences in the choice variables. Numerical examples show that the effect of the Samaritan's Dilemma outweighs the effect of the greater uncertainty of future income in the Nash equilibrium. However, the divergence in saving between the two solutions is rather small. In the literature, uncertain lifetime has been used to explain both unexpectedly low and unexpectedly high saving by the elderly. In The Effect of Uncertain Lifetime on the Saving of the Elderly, risk is introduced into the remaining lifetime and the consequences of a background risk are investigated. Introducing uncertain lifetime into the certainty model results in a slower decumulation of wealth from the date of retirement. On the contrary, introducing uncertain lifetime into a model with uncertain investment income results in a swifter decumulation and an earlier depletion of wealth.

Efficient control is often the most cost-effective option to improve on the running cost of a Three-Pipe Water Pumping System. However, the effect of changing the control strategy (i.e. on energy consumption) is usually difficult to predict. To obtain this information more easily, a new simulation tool, QUICKcontrol, was developed. This new tool was used to investigate the energy cost savings potential in a Three-Pipe Water Pumping System. The influence of pump scheduling, dam level set points, control parameters and different combinations thereof was investigated. The simulation models were firstly verified with measurements obtained from the existing system to confirm their accuracy for realistic control retrofit simulations. With the aid of the integrated simulation tool it was possible to predict savings of R 195'000 per year with an average 3.8 MW of load shifted. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2005.

MBA Professional Report / Approved for public release; distribution in unlimited. / The purpose of this research is to study the federal government's historical use of public-private partnerships (PPPs) and their view on the issue. Then we study recent applications (case studies) of innovative financing arrangements by Hannon Armstrong, LLC, an Annapolis, Maryland based financial services firm. The intention is to build upon previous Naval Postgraduate School research efforts is this subject; specifically, expanding upon the efforts of Professor San Miguel, Shank and Summers by investigating current examples of PPPs. First, we examine Hannon Armstrong's "fee for service contract" solution to the lack of appropriated capital funds needed for a vital fiber-optic link near the Arctic Circle. Then, we will explore the history of the Energy Saving Performance Contracts (ESPCs), which have been a useful tool in reducing the energy consumption throughout the federal government. Historically, this program has only been used for fixed assets. There is little debate over the success of these contracts in reducing energy consumption. The authors believe that applying Energy Saving Performance Contracts to mobile assets could further reduce the energy consumption of the Department of Defense (DoD) and save tax-payers millions of dollars.

High mobility has been a standard in the modern world for decades. This has resulted in high energy consumption, diminishing fossil energy reserves and rising levels of greenhouse gases. By recovering the energy lost in deceleration of vehicles the total energy consumption can be decreased and exhaust emissions reduced. This can be done with a kinetic energy recovery system (KERS) that converts kinetic energy to electric energy during deceleration, which then can be used for acceleration. KERS requires an electrical storage device with high power density, due to the high power levels generated at heavy braking. Batteries does not generally meet these requirements, especially in the cost-effective point of view, but different types of capacitors can be used to obtain a cheap and effective system. To get such an energy storage device small, lightweight and inexpensive while the technology is sustainable requires avoidance of rare metals and hazardous materials. In this master thesis energy and power levels for KERS has been modelled, based on standardized measurements techniques and small paper-based supercapacitors have been built and tested in order to model size, weight and price for a full-scale energy storage device to a KERS-application. The models showed that energy consumption in urban traffic could be reduced with 18% and with an electrode material for the energy storage device with a capacitance of about 1500 F/m2 a reasonable size and weight is obtained. To reach these values of capacitance in paper-based supercapacitors further testing is required on area and layer dependence and for different electrodes.

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Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 146-150).