Homogeneous Charge Compression Ignition (HCCI) Engines hold promises of being the next generation of internal combustion engines due to their ability to produce high thermal efficiencies and low emission levels. HCCI combustion is achieved through the auto-ignition of a compressed homogenous fuel-air mixture, thus making it a "fusion" between spark-ignition and compression-ignition engines. The main challenge in developing HCCI engines is the absence of a combustion trigger hence making it difficult to control its combustion timing. The aim of this research project is to model and control a natural gas HCCI engine. Since HCCI depends primarily on temperature and chemical composition of the mixture, Exhaust Gas Recirculation (EGR) is used to control ignition timing. In this research, a thermodynamical, physics-based nonlinear model is developed to capture the main features of the HCCI engine. In addition, the Modified Knock Integral Model (MKIM), used to predict ignition timing, is optimized. To validate the nonlinear model, ignition timing under varying conditions using the MKIM approach is shown to be in accordance with data acquired from a model developed using a sophisticated engine simulation program, GT-Power. Most control strategies are based on a linear model, therefore, the nonlinear model is linearized using the perturbation method. The linear model is validated by comparing its performance with the nonlinear model about a suitable operating point. The control of ignition timing can be defined as a regulation process where the goal is to force the nonlinear model to track a desired ignition timing by controlling the EGR ratio. Parameters from the linear model are used to determine the gains of the LQR controller. The performance of the controller is validated by implementing it on the nonlinear model and observing its ability to track the desired timing with 0.5% error within a certain operating range. To increase the operating range of the controller and reduce steady-state error, an integrator is added to the LQR. Finally, it is shown that the LQR controller is able to successfully reject disturbance, parameter variation, as well as noise.

Timing är ett uttryck som återfinns i vår vardag; inom musiken, sport, inlärning, undervisning, retorik, aktiehandel och så vidare. Listan kan göras lång. Som gammal köpman i modebranschen lärde jag mig att inte ens i denna bransch behöver aktörer vara först ut[1] för att lyckas bäst, utan att det mesta handlar om att agera i rätt tid. I mitt intresse för vad som är "agerande i rätt tid" har jag valt att studera begreppet timing i ett närmare perspektiv.   Detta arbete har fokuserats på timing inom organisation och marknadsföring. Jag har tyvärr måst konstatera att timing som begrepp i organisations- och marknadsföringslitteraturen så gott som utelämnats, samtidigt som en mängd liknande uttryck används som är relaterade till tid och utnyttjande av tid. Denna studie har därför genomförts genom utforskning av ett begränsat material bestående av vetenskapliga artiklar och empiriska undersökningar där timing har fått en central del i sina respektive sammanhang. Arbetsmaterialet är huvudsakligen sekundärdata där artiklarna presenterar olika syn och resultat, kring värdemätning av olika timingsituationer. Forskarna som skrivit artiklarna har studerat olika företag, branscher eller marknader. Flertalet av författarna, tycker som jag att det är väl lite forskat kring timing och timingliknande ageranden inom organisationer och ser i hög grad sina arbeten, som något av de "första stapplande stegen", mot en början till forskning kring timing.   Syftet med mitt arbete har varit att presentera en samlad bild av hur timing behandlas i litteraturen om organisationer och marknadsföring i olika situationer och kontexter.   De forskare och artikelförfattare som jag jobbat med är ganska enade när det gäller uppdelning av olika timingstadier, som organisationer kan välja mellan, i sina strategier att göra entré på en ny marknad. De delar upp dessa stadier i tre delar, pionjärskap, tidiga efterföljare alternativt sena efterföljare. Gemensamma teorier har varit att entrébarriärer skapas vid pionjärers entré, för efterföljare att ta sig över eller bryta igenom och att detta är av stor betydelse för hur en ny bransch eller branschförgrening utvecklas som helhet. En annan teori som får stort stöd är, att mängden aktörer på marknaden eller mängden potentiella aktörer till nya marknader påverkar andra organisationers timing att göra entré till dessa.   Nämnda författare i teoridelen använder sig flitigt av begreppet timing men verkar ändå inte ha något syfte att förklara själva uttryckets betydelse. Författarna talar snarare om timing i sammanhang som anpassning till tid eller tidshändelser som att vara först, före eller efter och att det kan vara bättre för vissa organisationer att välja en av dessa timingstrategier beroende på organisationens storlek och marknadsposition eller i vilken teknologisk timing företaget eller marknadsutvecklingen är i och här stannar författarna.  En av författarna kritiserar andras undersökningar, som utifrån empiriska mätningar och resultat tolkar vissa fenomen som någon form av bevis. Samma författare påvisar att branschskillnader är rådande och tycker att det med största försiktighet skall generaliseras över branschgränser gällande timing.   Mina litteraturstudier har resulterat i att jag skapat en modell som ringar in timing som begrepp, inom såväl marknadsföring som organisation. Denna modell och uppsats hoppas jag kan användas kan användas i praktiken och vid vidare forskning i ämnet.   [1] S.k. "first mover advantage" / This paper focuses on the concept of Timing and its importance in a marketing and organisational context. My purpose has been to present an overall picture about timing by illuminating valuations in earlier research, in more everyday situations and in a linguistic sense. The issue has been to match this with today's marketing and organizational literature. As a result of this study I have created a model which summarizes the concept of Timing. I hope this model and my study can be useful in future research and in practical use.

Previous investigations comparing direct versus indirectly cued movements have consistently shown that indirectly cued movements take longer to prepare (Neely and Heath, 2010) and involve the recruitment of additional brain areas (Connolly et al., 2000). This increase in processing time has been associated with the additional cognitive transformations required of the task (Neely and Heath, 2010). In the present study we investigated whether differences between direct versus indirectly cued movements are also reflected in the time course of motor preparation. Participants performed a targeting task, moving directly to the location of a visual cue (i.e., directly cued movement) or to a location that differed by 60˚, 90˚, or 120˚ with respect to the visual cue provided (i.e., indirectly cued movements). Participants were instructed to initiate their movements concurrently with an anticipated go-signal. To examine the time course of motor preparation, a startling acoustic stimulus (SAS, 124dB) was randomly presented 150 ms, 500 ms, or 1000 ms prior to the go-signal. Results from the startle trials revealed that the time course of motor preparation was similar regardless of the angle of rotation required and hence whether it was a direct or indirectly cued trial. Specifically, motor preparation was delayed until less than 500 ms prior to movement initiation for both direct and indirectly cued movements. These findings indicate that similar motor preparation strategies are engaged for both types of cued movements, suggesting that the time to prepare a motor response may be similar regardless of whether a cognitive transformation is required.

The traditional model of cryptography examines the security of cryptographic primitives as mathematical functions. This approach does not account for the physical side effects of using these primitives in the real world. A more realistic model employs the concept of a <I>side channel</I>. A side channel is a source of information that is inherent to a physical implementation of a primitive. Research done in the last half of the 1990s has shown that the information transmitted by side channels, such as execution time, computational faults and power consumption, can be detrimental to the security of ciphers like DES and RSA. This thesis surveys the techniques of side channel cryptanalysis presented in [Kocher1996], [Boneh1997], and [Kocher1998] and shows how side channel information can be used to break implementations of DES and RSA. Some specific techniques covered include the timing attack, differential fault analysis, simple power analysis and differential power analysis. Possible defenses against each of these side channel attacks are also discussed.

This dissertation consists of two parts. The theme connecting the two parts is the role of uncertainty. The first part focuses on the role of uncertainty in cooperative bargaining and public decision making. I provide an axiomatic characterization of the normalized utilitarian solution to bargaining problems involving uncertainty. In addition to three basic axioms that are common in the bargaining literature, I propose the axiom of weak linearity to characterize the solution. In the second part I study uncertainty in non-cooperative games by designing a principal agent model of public bailouts. The first essay in this part sets up the model and shows that the moral hazard problem, namely the Samaritan's dilemma, exists without an altruistic principal. The second essay in this part builds upon the previous essay and focuses on the informational elements in a bailout game. Mainly, I show the existence of a separating equilibrium, where public bailouts serve as a mechanism to reveal essential information to outsiders and in which the good-type agents can benefit from rejecting a bailout offer.

The traditional model of cryptography examines the security of cryptographic primitives as mathematical functions. This approach does not account for the physical side effects of using these primitives in the real world. A more realistic model employs the concept of a <I>side channel</I>. A side channel is a source of information that is inherent to a physical implementation of a primitive. Research done in the last half of the 1990s has shown that the information transmitted by side channels, such as execution time, computational faults and power consumption, can be detrimental to the security of ciphers like DES and RSA. This thesis surveys the techniques of side channel cryptanalysis presented in [Kocher1996], [Boneh1997], and [Kocher1998] and shows how side channel information can be used to break implementations of DES and RSA. Some specific techniques covered include the timing attack, differential fault analysis, simple power analysis and differential power analysis. Possible defenses against each of these side channel attacks are also discussed.

Recent advances in Micro Electro-Mechanical Systems technology, wireless communications, and digital electronics have enabled the development of low-cost, low-power, multifunctional sensor nodes that are small in size and communicate untethered in short distances. These tiny sensor nodes, which consist of sensing, data processing, and communicating components, leverage the idea of sensor networks based on collaborative effort of a large number of nodes. A wide range of applications utilizing low-end sensor nodes to collaborative work together is envisioned for sensor networks. Some of the application areas are health, military, and security. For example, sensor networks can be used to detect foreign chemical agents in the air and the water. They can help to identify the type, concentration, and location of pollutants. In essence, sensor networks will provide the end user with intelligence and a better understanding of the environment. Realization of these and other sensor network applications require certain fundamental protocols and schemes. The objective of this thesis is to provide some of the basic building blocks that are necessary for sensor networks. These basic blocks are in the areas of routing, time synchronization, and localization. The routing protocol allows different types of traffics to be delivered and fused during delivery to lower the amount of information exchange. The time synchronization protocol enables the sensor nodes to maintain a similar time while the localization technique provides a way to find the sensor nodes in the sensor field. The routing, time synchronization, and localization schemes may be used to provide Quality-of-Service when data is gathered from the sensor networks.

As semiconductor technology advances into the nano-scale era and more functional blocks are added into systems on chip (SoC), the interface between circuit design and manufacturing is becoming blurred. An increasing number of features, traditionally ignored by designers are influencing both circuit performance and yield. As a result, design tools need to incorporate new factors. One important source of circuit performance degradation comes from deterministic within-die variation from lithography imperfections and Cu interconnect chemical mechanical polishing (CMP). To determine how these within-die variations impact circuit performance, a new analysis tool is required. Thus a methodology has been proposed to involve layout-dependent within-die variations in static timing analysis. The methodology combines a set of scripts and commercial tools to analyze a full chip. The tool has been applied to analyze delay of ISCAS85 benchmark circuits in the presence of imperfect lithography and CMP variation. Also, this thesis presents a methodology to generate test sets to diagnose the sources of within-die variation. Specifically, a delay fault diagnosis algorithm is developed to link failing signatures to physical mechanisms and to distinguish among different sources of within-die variation. The algorithm relies on layout-dependent timing analysis, path enumeration, test pattern generation, and correlation of pass/fail signatures to diagnose lithography-caused delay faults. The effectiveness in diagnosis is evaluated for ISCAS85 benchmark circuits.

In this thesis, a blind symbol timing synchronization algorithm based on cyclic prefix for OFDM systems in multipath fading channels is proposed. It finds the starting point of symbol timing for using appropriate weights which are designed from channel delay spread characteristics. In multipath fading channels, the conventional ML (maximum likelihood) algorithm estimate is biased and has a large variance due to the effect of channel delay spread. The proposed exponential weighting methods not only solve the above problems but also improve the accuracy of symbol timing. Particularly, the proposed method does not require the information of SNR and channel length. From computer simulation results, the proposed method outperforms the other conventional algorithms and is also robust against the effect of multipath fading channels.

This dissertation presents the results of the first search for heavy, neutral, longlived particles that decay to photons at a hadron collider. We use a sample of +jet+missing transverse energy events in p¯p collisions at ps = 1.96 TeV taken with the Collider Detector at Fermilab. Candidate events are selected based on the arrival time of a high-energy photon at the electromagnetic calorimeter as measured with a timing system that was recently installed. The final result is that we find 2 events, using 570±34 pb−1 of data collected during 2004-2005 at the Fermilab Tevatron, consistent with the background estimate of 1.3±0.7 events. While our search strategy does not rely on model-specific dynamics, we interpret this result in terms of cross section limits in a supersymmetric model with e01! eG and set a world-best e01 mass reach of 101 GeV/c2 at e = 5 ns. We can exclude any +jet+missing transverse energy signal that would produce more than 5.5 events.