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Denna avhandling i datalogi föreslår modeller för hur vissa beräkningsmässiga uppgifter kan utföras av hjärnbarken. Utgångspunkten är dels kända fakta om hur en area i hjärnbarken är uppbyggd och fungerar, dels etablerade modellklasser inom beräkningsneurobiologi, såsom attraktorminnen och system för gles kodning. Ett neuralt nätverk som producerar en effektiv gles kod i binär mening för sensoriska, särskilt visuella, intryck presenteras. Jag visar att detta nätverk, när det har tränats med naturliga bilder, reproducerar vissa egenskaper (receptiva fält) hos nervceller i lager IV i den primära synbarken och att de koder som det producerar är lämpliga för lagring i associativa minnesmodeller. Vidare visar jag hur ett enkelt autoassociativt minne kan modifieras till att fungera som ett generellt sekvenslärande system genom att utrustas med synapsdynamik. Jag undersöker hur ett abstrakt attraktorminnessystem kan implementeras i en detaljerad modell baserad på data om hjärnbarken. Denna modell kan sedan analyseras med verktyg som simulerar experiment som kan utföras på en riktig hjärnbark. Hypotesen att hjärnbarken till avsevärd del fungerar som ett attraktorminne undersöks och visar sig leda till prediktioner för dess kopplingsstruktur. Jag diskuterar också metodologiska aspekter på beräkningsneurobiologin idag. / In this thesis I take a modular approach to cortical function. I investigate how the cerebral cortex may realise a number of basic computational tasks, within the framework of its generic architecture. I present novel mechanisms for certain assumed computational capabilities of the cerebral cortex, building on the established notions of attractor memory and sparse coding. A sparse binary coding network for generating efficient representations of sensory input is presented. It is demonstrated that this network model well reproduces the simple cell receptive field shapes seen in the primary visual cortex and that its representations are efficient with respect to storage in associative memory. I show how an autoassociative memory, augmented with dynamical synapses, can function as a general sequence learning network. I demonstrate how an abstract attractor memory system may be realised on the microcircuit level -- and how it may be analysed using tools similar to those used experimentally. I outline some predictions from the hypothesis that the macroscopic connectivity of the cortex is optimised for attractor memory function. I also discuss methodological aspects of modelling in computational neuroscience. / QC 20100916

Dexter Morgan is a serial killer, but he may not be blameworthy for his actions There are two possible explanations that could absolve Dexter of moral responsibility: (1) His inability to empathize with others makes it so that he cannot make appropriate moral decisions. Or (2) his serial killing tendencies are determined in nature, set off by events of which he had no control. I conclude that Dexter is, in fact, morally responsible for his actions because he is capable of second order desires

The first version of the Senior processor was created as part of a thesis projectin 2007. This processor was completed and used for educational purposes atLinköpings University. In 2008 several parts of the processor were optimized andthe processor expanded with additional functionality as part of another thesisproject. In 2009 an EU funded project called MULTI-BASE started, in which theComputer Division at the Department of Electrical Engineering participated in.For their part of the MULTI-BASE project, the Senior processor was selected tobe used. After continuous revision and development, this processor was sent formanufacturing. The assignment of this thesis project was to test and verify the different func-tions implemted in the Senior processor. To do this a PCB was developed fortesting the Senior processor together with a Virtex-4 FPGA. Extensive testingwas done on the most important functions of the Senior processor. These testsshowed that the manufactured Senior processor works as designed and that it alonecan perform larger calculations and use external hardware accelerators with thehelp of its various interfaces. / Den första versionen av Senior processorn skapades som en del i ett examensarbe-te under 2007, denna processor färdigställdes och användes i utbildningssyfte påLinköping Universitet. 2008 optimerades flera delar av processorn och utökadesmed extra funktionalitet som del av ytterligare ett examensarbete. 2009 startadeett EU finansierat projekt vid namn MULTI-BASE, som ISYs Datortekniks avdel-ning deltar i. Till deras del av MULTI-BASE projektet valdes Senior processorn attanvändas, efter ytterligare utveckling skickades denna processor för tillverkning. Detta examensarbete hade i uppgift att testa och verifiera de olika funktionernasom Senior processorn har implementerats med. För att göra detta tillverkades ettkretskort som ska användas för att testa Senior processorn tillsammans med enVirtex-4 FPGA. Utförliga tester gjordes på de viktigaste funktionerna hos Seniorprocessorn, dessa tester visade att den tillverkade Senior processorn fungerar somplanerat. Den kan på egen hand utföra större beräkningar och använda sig avexterna hårdvare acceleratorer med hjälp av sina olika gränssnitt.

As demand for higher bandwidth I/O grows, the front end design of serial link becomes significant to overcome stringent timing requirements on noisy and bandwidthlimited channels. As a clock reconstructing module in a receiver, the recovered clock quality of Clock and Data Recovery is the main issue of the receiver performance. However, from unknown incoming jitter, it is difficult to optimize loop dynamics to minimize steady-state and dynamic jitter. In this thesis a 10 Gb/s adaptive loop bandwidth clock and data recovery circuit with on-chip loop filter is presented. The proposed system optimizes the loop bandwidth adaptively to minimize jitter so that it leads to an improved jitter tolerance performance. This architecture tunes the loop bandwidth by a factor of eight based on the phase information of incoming data. The resulting architecture performs as good as a maximum fixed loop bandwidth CDR while tracking high speed input jitter and as good as a minimum fixed bandwidth CDR while suppressing wide bandwidth steady-state jitter. By employing a mixed mode predictor, high updating rate loop bandwidth adaptation is achieved with low power consumption. Another relevant feature is that it integrates a typically large off-chip filter using a capacitance multiplication technique that employs dual charge pumps. The functionality of the proposed architecture has been verified through schematic and behavioral model simulations. In the simulation, the performance of jitter tolerance is confirmed that the proposed solution provides improved results and robustness to the variation of jitter profile. Its applicability to industrial standards is also verified by the jitter tolerance passing SONET OC-192 successfully.

Emerging "bandwidth hungry" applications such as high definition video distribution and ultra fast multimedia side-loading have extended the need for multi-gigabit wireless solutions beyond the reach of conventional WLAN technology or even more recently emerging UWB and MIMO systems. The availability of 7GHz of unlicensed bandwidth in the 60GHz spectrum, represents a unique opportunity to address such data-throughput requirements. The 60GHz Integrated CMOS digital radio chipset comprises of PHY and MAC layers, RF transceiver, High-Speed Digital Interface and an underlying Serial Communication Fabric. To have a complete communication solution compliant with the latest ECMA-369, ISO/DIS 13156 and IEEE 802.15.3c standards, we build a million gate digital implementation of MAC and PHY. The Serial Peripheral Interface (SPI) serves as the bridge between the higher layers in the communication stack (PAL-MAC) and the lower layers like PHY-RF Front End. The MAC module can setup the communication link on the fly by tuning parameters such as operating channel, channel bonding and bandwidth, data rates, error correction mechanisms, handshaking mechanisms, etc, by using the SPI to communicate with internal components. The SPI interface plays a crucial rule in not only this, but also during the testing and debug phase. Operation of each of the RF modules is monitored through the serial interface using local SPI slaves which are hooked up to the 4-wire serial bus running all through the chip. The SPI host controller emulates an embedded protocol analyzer. For calibration and fine tuning purposes, digital settings can also be loaded onto these modules through the SPI interface. R-2R DACs are used to convert these commands into analog voltages which then provide a tunable bias to the RF and mixed-signal modules. Other key functions of this serial communication and control interface are: Initialization of all of the RF and mixed signal modules, DC calibration of data converter, PLL and other mixed-signal modules, data acquisition, parametric tuning for digital modules such as linear equalizer, Gain Control loops (AGC, VGA), etc. Ultra high speed digital Input-Output buffers are used to provide an external data interface to the radio chipset. These high speed I/Os are also used in the gbps (gigabit-per-second) link for data transfer between the RF transceiver chip and the PHY-MAC baseband chip. The IOs are expected to comply with different signaling standards such as LVDS, SLVS200, SLVS400, etc. A robust system involves a meticulous pad ring design with proper power domains and power cuts. Full-chip integration of the digital PHY, MAC, peripheral logic and IO ring is done in a semi-custom fashion.

Auf Grund der dominierenden Orientierung an Produkttypen in der Serienproduktion sowie der Spezialisierung von Zulieferfirmen und deren Abhängigkeit von Finalproduzenten können die strategischen Zuliefernetze als sehr begrenzt wandlungsfähig eingeschätzt werden. Defizite derartiger Kooperationsformen, die u. a. auf hierarchischen Strukturen in und zwischen den Unternehmen aufbauen, werden im Rahmen einer Praxisanalyse bestätigt. Ziel der Arbeit ist die Entwicklung einer Methode zur Planung und Gestaltung der Transformation derzeitiger Unternehmen zu Kompetenzzellenbasierten Netzen (TransKompNet- Methode), die unternehmens- und branchenneutral ausgearbeitet und am Objektbereich der Serienproduktion praktisch evaluiert wird. Vorliegende Arbeit skizziert damit ein Lösungskonzept für Systemlieferanten und Serienfertiger, das die dezentralisierte Dekomposition der monolithischen Produkt-, Prozess- und Systemstrukturen erlaubt und Möglichkeiten zur Strukturveränderung bei den Lieferanten diskutiert. In unternehmensübergreifenden Netzen wird für Zulieferer ein Auffangen deren kleinsten Leistungseinheiten durch Entkopplungs-/Ausweichproduktionen nachgewiesen.

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This thesis consisted of experiments designed to explore the construct of attention and investigate the disruptive effects of psychotomimetics, with a specific focus on NMDA antagonists. Phencyclidine (PCP) was administered through a variety of treatment regimens in order to to determine the ability of inducing cognitive-specific disruptions in attentional functioning. The hypothesis that sub-chronic exposure to PCP would result in persistent attentional impairment was tested, using the 5-choice serial reaction time task (5-CSRTT). The 5-CSRTT assesses not only visuospatial attention, but also components of impulsivity, compulsivity, speed of processing and motivation. It was determined that an additional task-related intervention that increased the attentional load was required to elucidate attentional impairment following sub-chronic PCP treatment. The ability of rats to perform the modified version of the 5-CSRTT, known as the 5-choice continuous performance test (5C-CPT), was investigated. The 5C-CPT was implemented to provide a task that may have greater analogy to the human CPT, than the original 5-CSRTT. The consequence of dopaminergic D1 system activation was investigated. It was revealed that D1 partial agonism improved attentional performance in a baseline-dependent manner. Following successful acquisition of the task, it was shown that repeated PCP treatment induced cognitive disruption that was cognitive-specific, and not confounded by generalised response disruption. Furthermore, a partial attenuation of the PCP-induced performance disruption was achieved following administration of the D1 partial agonist, SKF 38393. Moreover, sub-chronic PCP treatment was shown to impair 5C-CPT performance in the drug-free state. However, an additional challenge that further increased the attentional load was needed to elucidate a performance deficit. This highlighted that sustained attention/vigilance is sensitive to persistent impairment following sub-chronic PCP administration in a manner consistent with deficits observed in schizophrenia patients. This prompted the investigation that tested the hypothesis that sub-chronic PCP treatment could induce enduring structural deficits in regions associated with attentional performance. Magnetic resonance imaging (MRI) was conducted, in conjunction with 5-CSRTT and pre-pulse inhibition (PPI). It was revealed that sub-chronic PCP treatment resulted in morphological brain abnormalities in brain regions associated with 5-CSRTT performance. This was coupled with deficits in sustained attentional performance following an increase in attentional load, yet PPI was unaffected. Taken together, these findings suggested sub-chronic PCP treatment impairs attentional functionality, an effect that dissociates between effortful and passive attentional processes.

Victorian serial novels were bound with pages upon pages of advertisements marketing goods to readers, yet the relative inattention paid to this significant material component of the novel is surprising. This project explores the interaction between fictional narrative and commercial advertisements, and aims to recover the material context in which three Victorian novels—Bleak House, Middlemarch, and Adventures of Huckleberry Finn—were first published and read. These three case studies—a novel published in 20 monthly serial numbers, another packaged in the rare format of eight “books” in bimonthly installments, and the third published in a monthly magazine in three excerpts—are exemplary of a larger phenomenon in Victorian book production wherein fiction and commerce were inextricably bound. This project investigates the ways in which the advertisements can be reconceived as a significant element of the novel, mediating the reader’s experience of the text. The Bleak House chapter examines how the advertisements for hair products in the “Bleak House Advertiser” serve to highlight an aspect of Charles Dickens’s text about Victorian responses to the mass of new consumer goods and individuals’ desire to control the physical aspects of their world. The following chapter considers George Eliot’s (Mary Ann Evans’s) Middlemarch, finding that just as the narrator’s asides compel readers to attend to the temporal difference between the 1830s setting of the novel and the 1870s perspective of the serial edition, sewing machine advertisements in the advertising supplement of the novel serve to remind readers of their role as observers of past events. The examination of Mark Twain’s (Samuel Clemens’s) Huck Finn, as published in three excerpts in The Century Illustrated Monthly Magazine, demonstrates that the magazine articles, the excerpts from Huck Finn, and the advertisements all engage in a project of unifying the nation and alleviating the physical and metaphorical wounds of war. The unity of the message emerges when the excerpts are read together with the many advertisements for wheelchairs and other such implements for disabled bodies. The dissertation ends with a chapter indicating the merits of further analysis and critical discussion of advertisements in the undergraduate literature classroom. / text