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Das Sprachsystem der Naxi
(2016)
Die Naxi verwenden eine Sprache, in der Segmente und Suprasegmente in komplexer Weise in Wörtern zum Ausdruck kommen. Im Satz wird die Grammatik grundsätzlich in analytischer Weise durch Partikeln strukturiert. Die Naxi verwenden einzigartige Zeichen, die entweder stilisierte Umrisse von der Natur (die Domba-Zeichen) oder hoch abstrakt (die Geba-Zeichen) sind, um Gegenstände bzw. Ausprachen zu symbolisieren.
Für grenzüberschreitend tätige Unternehmen besteht durch das internationale Steuersatzgefälle und die fehlende Finanzierungsneutralität ein Anreiz, durch konzerninterne Finanzierungsstrukturen Gewinne zu verlagern, um dadurch die Gesamtsteuerbelastung auf Konzernebene zu senken. Während Unternehmen in Niedrigsteuerländern vorrangig mit Eigenkapital ausgestattet werden, haben Hochsteuerländer mit der Problematik einer übermäßigen Fremdkapitalausstattung und der damit verbundenen Erosion des Steuersubstrats zu kämpfen. Um solchen Gewinnverschiebungen entgegenzuwirken, greifen viele Staaten auf Regelungen zu einer Beschränkung von übermäßiger Fremdfinanzierung zurück. Insbesondere sollen mit diesen Regelungen Steuergestaltungen und Missbrauchsmöglichkeiten eingeschränkt und den damit verbundenen asymmetrischen Finanzierungsstrukturen entgegengewirkt werden. Vor diesem Hintergrund analysiert die vorliegende Arbeit den Einfluss von verschiedenen Zinsabzugsbeschränkungen auf konzerninterne Finanzierungsentscheidungen. Ziel der vorliegenden Arbeit ist, grundlegende Wirkungszusammenhänge zwischen der Vergabe von Eigen- und Fremdkapital im grenzüberschreitenden Kontext aufzuzeigen, wobei verschiedene Ansätze zur Beschränkung einer übermäßigen Fremdfinanzierung Berücksichtigung finden.
Advanced driver assistance systems play an important role in increasing the safety on today's roads. The knowledge about the other vehicles' positions is a fundamental prerequisite for numerous safety critical applications, making it possible to foresee critical situations, warn the driver or autonomously intervene. Forward collision avoidance systems, lane change assistants or adaptive cruise control are examples of safety relevant applications that require an accurate, continuous and reliable relative position of surrounding vehicles.
Currently, the positions of surrounding vehicles is estimated by measuring the distance with e.g. radar, laser scanners or camera systems. However, all these techniques have limitations in their perception range, as all of them can only detect objects in their line-of-sight. The limited perception range of today's vehicles can be extended in future by using cooperative approaches based on Vehicle-to-Vehicle (V2V) communication.
In this thesis, the capabilities of cooperative relative positioning for vehicles will be assessed in terms of its accuracy, continuity and reliability. A novel approach where Global Navigation Satellite System (GNSS) raw data is exchanged between the vehicles is presented. Vehicles use GNSS pseudorange and Doppler measurements from surrounding vehicles to estimate the relative positioning vector in a cooperative way. In this thesis, this approach is shown to outperform the absolute position subtraction as it is able to effectively cancel out common errors to both GNSS receivers. This is modeled theoretically and demonstrated empirically using simulated signals from a GNSS constellation simulator.
In order to cope with GNSS outages and to have a sufficiently good relative position estimate even in strong multipath environments, a sensor fusion approach is proposed. In addition to the GNSS raw data, inertial measurements from speedometers, accelerometers and turn rate sensors from each vehicle are exchanged over V2V communication links. A Bayesian approach is applied to consider the uncertainties inherently to each of the information sources. In a dynamic Bayesian network, the temporal relationship of the relative position estimate is predicted by using relative vehicle movement models.
Also real world measurements in highway, rural and urban scenarios are performed in the scope of this work to demonstrate the performance of the cooperative relative positioning approach based on sensor fusion. The results show that the relative position of another vehicle towards the ego vehicle can be estimated with sub-meter accuracy in highway scenarios. Here, good reliability and 90% availability with an uncertainty of less than 2.5m is achieved. In rural environments, drives through forests and towns are correctly bridged with the support of on-board sensors. In an urban environment, the difficult estimation of the ego vehicle heading has a mayor impact in the relative position estimate, yielding large errors in its longitudinal component.
Im Schulalltag müssen Lehrkräfte nicht nur die Schülerleistung, sondern auch andere Schülermerkmale zutreffend beurteilen. Die vorliegende Arbeit, welche drei Studien umfasst, beschäftigt sich daher mit der Urteilsgenauigkeit von Mathematiklehrkräften zu verschiedenen Schülermerkmalen. Zudem wurden auch die Stabilitäten und Auswirkungen der Genauigkeit von Lehrkrafturteilen analysiert. Die Urteilsgenauigkeit stellt den Kern der diagnostischen Kompetenz von Lehrkräften dar, unter der man die Fähigkeit von Lehrkräften versteht, Schüler- und Aufgabenmerkmale zutreffend einschätzen zu können.
In der ersten Studie wurde die Urteilsgenauigkeit von Mathematiklehrkräften in der Einschätzung von Mathematikleistung, Konzentration, Arbeits- und Sozialverhalten untersucht. Auch wurde überprüft, ob die Urteilsgenauigkeit mit soziodemografischen Lehrkraftmerkmalen zusammenhängt und wodurch Lehrkrafturteile vorhergesagt werden. An der Untersuchung nahmen 357 Realschulfünftklässler sowie deren 17 Mathematiklehrkräfte teil. Die Lernenden bearbeiteten einen Mathematikleistungstest sowie einen Konzentrationstest und füllten Fragebögen zum Arbeits- und Sozialverhalten aus. Währenddessen schätzten die Lehrkräfte die verschiedenen Schülermerkmale ein. Lehrkräfte schätzten die Rangfolge der Schülerleistung mit mittlerer Genauigkeit ein, die Beurteilung von Konzentration, Arbeits- und Sozialverhalten fiel ihnen schwerer. Lehrkräfte überschätzten die Schülerleistung. Weder Alter, Geschlecht noch Berufserfahrung der Lehrkräfte hingen mit der Urteilsgenauigkeit zusammen. Lehrkrafturteile zur Schülerleistung und zu nicht-leistungsbezogenen Schülermerkmalen wurden durch sachfremde Urteilsmerkmale verzerrt.
Die zweite Studie baut auf der ersten Arbeit auf und erweitert diese um einen Messzeitpunkt. Da über Stabilität, genauigkeitsbeeinflussende Faktoren und differenzielle Wirkungen des Lehrkrafturteils zur Schülerleistung relativ wenig bekannt ist, wurden in dieser Studie diese Aspekte analysiert. An der Untersuchung nahmen 294 Realschülerinnen und -schüler sowie deren 17 Mathematiklehrkräfte teil. Die Fünftklässlerinnen und Fünftklässler bearbeiteten standardisierte Mathematikleistungstests und machten Angaben zum wahrgenommenen Lehrkraftverhalten. Parallel dazu schätzten die Lehrkräfte die Testleistungen ein und beantworteten Fragen zur Bezugsnormorientierung. Die Rangkomponente, Übereinstimmung des Lehrkrafturteils mit den Schülerleistungen, verbesserte sich im Zeitraum eines halben Schuljahres signifikant. Sie korrelierte signifikant positiv mit der kriterialen Bezugsnormorientierung. Die Genauigkeit des Lehrkrafturteils zum Schulhalbjahr, indiziert als Leistungsüber- und -unterschätzung, war prädiktiv für die Schülerleistung zu Schuljahresende. In der Leistung überschätzte Lernende wiesen im Vergleich zu unterschätzten Lernenden den größeren Leistungszuwachs auf und nahmen das Lehrkraftverhalten anders wahr.
Die dritte Studie ist ebenfalls längsschnittlich angelegt und umfasst zwei Messzeitpunkte, weswegen die Stabilitäten von Lehrkrafteinschätzungen und Schülermerkmalen sowie die differenziellen Wirkungen von Lehrkrafteinschätzungen auf verschiedene Schülergruppen untersucht werden konnten. Im Abstand eines Jahres wurden in der dritten und vierten Klasse Daten von 152 Grundschülerinnen und -schülern sowie von deren zehn Mathematiklehrkräften gesammelt. Die Grundschülerinnen und -schüler bearbeiteten jeweils einen standardisierten Mathematikleistungstest und einen Fragebogen zum motivational-affektiven Erleben in der Schule. Zeitgleich schätzten die Lehrkräfte verschiedene Schülermerkmale auf Skalen ein. Die Rangreihungen der Lehrkräfte zu Testleistung, Lernfreude, Schuleinstellung und Anstrengungsbereitschaft verbesserten sich über den einjährigen Untersuchungszeitraum signifikant. Das Lehrkrafturteil zur Testleistung sowie zur Erfolgserwartung und die Schülermerkmale waren stabil. Der Zusammenhang zwischen der Urteilsgenauigkeit und den Schülermerkmalen spiegelte sich in Unterschieden zwischen den Schülergruppen wider: In der vierten Klasse hatten überschätzte Lernende eine höhere Testleistung, Erfolgserwartung und Lernfreude sowie ein höheres Fähigkeitsselbstkonzept und eine niedrigere Leistungsangst als unterschätzte Lernende.
Insbesondere die Ergebnisse zu den interindividuellen Unterschieden in der Urteilsgenauigkeit, die in allen drei Studien zu finden sind, lassen eine Förderung der Urteilsgenauigkeit wünschenswert erscheinen. Daher werden abschließend verschiedene Möglichkeiten zur Förderung der Urteilsgenauigkeit vorgestellt.
Splinekurven sind oft das erste Mittel der Wahl, wenn Daten interpoliert oder approximiert werden sollen. Sie spielen in vielen praktischen Anwendungsbereichen eine wichtige Rolle und sind in Bereichen des CAD/CAM nicht mehr weg zu denken. In der vorliegenden Arbeit werden in diesem Kontext Bahnpunkte zur Steuerung von Werkzeugmaschinen untersucht. Die Analyse wird mit Hilfe eines Multiresolution (MRA) Ansatzes für Splinekurven mit adaptiven Knotenfolgen realisiert. Dieser MRA Ansatz basiert auf einer Least-Squares-Projektion zum Knotenentfernen und unterscheidet sich somit zu bekannten Ansätzen, die auf orthogonalen Komplementen aufbauen. Des Weiteren wird ein Konzept zur Approximation von Orientierungsdaten mittels homogenen Quaternionensplines vorgestellt. Diese Splines leben auf der Sphäre und lassen sich mittels Knotenentfernen bzw. einfügen verfeinern. Somit lässt sich das vorgestellte MRA–Analyseverfahren ebenfalls auf diese Kurven anwenden. Weiter konnte für diese Kurven eine konvexe Hülle–Eigenschaft nachgewiesen werden.
In our knowledge-driven society, the acquisition and the transfer of knowledge play a principal role. Web search engines are somehow tools for knowledge acquisition and transfer from the web to the user. The search engine results page (SERP) consists mainly of a list of links and snippets (excerpts from the results). The snippets are used to express, as efficiently as possible, the way a web page may be relevant to the query.
As an extension of the existing web, the semantic web or “web 3.0” is designed to convert the presently available web of unstructured documents into a web of data consumable by both human and machines. The resulting web of data and the current web of documents coexist and interconnect via multiple mechanisms, such as the embedded structured data, or the automatic annotation.
In this thesis, we introduce a new interactive artifact for the SERP: the “Semantic Snippet”. Semantic Snippets rely on the coexistence of the two webs to facilitate the transfer of knowledge to the user thanks to a semantic contextualization of the user’s information need. It makes apparent the relationships between the information need and the most relevant entities present in the web page.
The generation of semantic snippets is mainly based on the automatic annotation of the LOD1’s entities in web pages. The annotated entities have different level of impor- tance, usefulness and relevance. Even with state of the art solutions for the automatic annotations of LOD entities within web pages, there is still a lot of noise in the form of erroneous or off-topic annotations. Therefore, we propose a query-biased algorithm (LDRANK) for the ranking of these entities. LDRANK adopts a strategy based on the linear consensual combination of several sources of prior knowledge (any form of con- textual knowledge, like the textual descriptions for the nodes of the graph) to modify a PageRank-like algorithm.
For generating semantic snippets, we use LDRANK to find the more relevant entities in the web page. Then, we use a supervised learning algorithm to link each selected entity to excerpts from the web page that highlight the relationship between the entity and the original information need.
In order to evaluate our semantic snippets, we integrate them in ENsEN (Enhanced Search Engine), a software system that enhances the SERP with semantic snippets.
Finally, we use crowdsourcing to evaluate the usefulness and the efficiency of ENsEN.
Opportunistic networks (OppNets) are human-centric mobile ad-hoc networks, in which neither the topology nor the participating nodes are known in advance. Routing is dynamically planned following the store-carry-and-forward paradigm, which takes advantage of people mobility. This widens the range of communication and supports indirect end-to-end data delivery. But due to individuals’ mobility, OppNets are characterized by frequent communication disruptions and uncertain data delivery. Hence, these networks are mostly used for exchanging small messages like disaster alarms or traffic notifications. Other scenarios that require the exchange of larger data (e.g. video) are still challenging due to the characteristics of this kind of networks. However, there are still multimedia sharing scenarios where a user might need switching from infrastructural communications to an ad-hoc alternative. Examples are the cases of 1) absence of infrastructural networks in far rural areas, 2) high costs due to roaming or limited data volumes or 3) undesirable censorship by third parties while exchanging sensitive content. Consequently, we target in this thesis a video dissemination scheme in OppNets.
For the video delivery problem in the sparse opportunistic networks, we propose a solution with the objective of reducing the video playout delay, so that enabling the recipient to play the video content as soon as possible even if at a low quality. Furthermore, the received video reaches later a higher quality level, ensuring a better viewing experience.
The proposed solution encloses three contributions. The first one is given by granulating the videos at the source node into smaller parts, and associating them with unequal redundancy degrees. This is technically based on using the Scalable Video Coding (SVC), which encodes a video into several layers of unequal importance for viewing the content at different quality levels. Layers are routed using the Spray-and-Wait routing protocol, with different redundancy factors for the different layers depending on their importance degree. In this context as well, a video viewing QoE metric is proposed, which takes the values of the perceived video quality, delivery delay and network overhead into consideration, and on a scalable basis.
Second, we take advantage of the small units of the Network Abstraction Layer (NAL), which compose SVC layers. NAL units are packetized together under specific size constraints to optimize granularity. Packets sizes are tuned in an adaptive way, with regard to the dynamic network conditions. Each node is enabled to record a history of environmental information regarding the contacts and forwarding opportunities, and use this history to predict future opportunities and optimize the sizes accordingly.
Lastly, the receiver (destination) node is pushed into action by reacting to missing data parts in a composite ``backward'' loss concealment mechanism. So, the receiver asks first for the missing data from other nodes in the network in the form of request-response. Then, since the transmission is concerned with video content, video frame loss error concealment techniques are also exploited at the receiver side. Consequently, we propose to combine the two techniques in the loss concealment mechanism, which is enabled then to react to missing data parts.
To study the feasibility and the applicability of the proposed solutions, simulation-driven experiments are performed, and statistical results are collected and analyzed. Consequently, we have got promising results that show the applicability of video dissemination in opportunistic delay tolerant networks, and open the door for a range of possible future works.
Eine medienbruchfreie, automatisierte Verarbeitung von Geschäftsdokumenten ist die Grundlage für effiziente und fehlerfreie unternehmensübergreifende Geschäftsprozesse. Im Bereich der digitalen Übertragung von Geschäftsdokumenten in Form von strukturierten Daten existiert hierfür eine Vielzahl von Ansätzen. Daneben werden viele Geschäftsdokumente nach wie vor in bildlicher Form, wie beispielsweise auf Papier, verwendet. In diesem Bereich sind die Dokumente nur selten auf eine automatisierte Verarbeitung ausgelegt. Die Einbettung von digital strukturierter Information, die für eine automatisierte Verarbeitung benötigt wird, erfolgt üblicherweise über optische Codes. Der inhaltliche Aufbau dieser Codes wird meist zwischen den beteiligten Unternehmen individuell vereinbart. Ein standardisierter Ansatz dafür fehlt. Um eine standardisierte Verwendung optischer Codes zu ermöglichen, wird in dieser Arbeit der Ansatz verfolgt, Geschäftsdokumente in XML-basierter Form optisch zu codieren. Damit können bereits existierende Standards für XML-basierte Geschäftsdokumente und optische Codes verwendet werden. Aufgrund der beschränkten Kapazität optischer Codes ist die Kompression von XML-Dokumenten der zentrale Untersuchungsgegenstand dieser Arbeit. Im Rahmen dessen wird die Leistung bestehender Kompressionsverfahren betrachtet und analysiert, inwiefern diese für die optische Codierung XML-basierter Geschäftsdokumente verbessert werden kann. In einem mehrstufigen Analyseprozess erfolgt die Entwicklung eines Verfahrens, das eine neuartige Kombination bestehender Konzepte zur XML-Kompression verwendet und damit höhere Kompressionsraten ermöglicht. Dazu wird ein facettiertes Klassifikationssystem mit technischen und funktionalen Merkmalen erarbeitet, mit dem potentiell relevante XML-Kompressionsverfahren identifiziert werden. Die konzeptionellen Bestandteile der ausgewählten Verfahren werden im Hinblick auf ihre Leistungsfähigkeit beurteilt und sinnvolle Konzepte zu einem parametrisierten Verfahren (PSXC für parametric schema-based XML compression) kombiniert. Im Rahmen einer Fallstudie zur optischen Codierung von Rechnungsdokumenten wird die Leistungsfähigkeit von PSXC im Vergleich zu bestehenden Allzweck- und XML-Kompressionsverfahren geprüft und gezeigt, dass die Größe optischer Codes mit PSXC reduziert werden kann.
In order to end poverty by 2030, the declared goal of the United Nations, a better understanding is needed which policies help poor households to escape poverty and how to end its inter-generational transmission.
Since the Millennium Declaration in September 2000, and the adoption of the Millennium Development Goals (MDGs), the delivery of basic social services, such as education, health, water supply and sanitation, has become the central focus of international development assistance.
However, the provision of basic social services is not necessarily sufficient to lead to an accumulation of human and productive capital, which would allow households to escape poverty and interrupt its inter-generational transmission.
To understand why people are poor, we need to understand what productive decisions poor households take, and to identify what constraints households face in their attempt to accumulate human, as well as, productive capital. A better understanding of such constraints could guide policies that have a long-term impact on poverty reduction and on development.
A number of factor could explain why poor households operate at unprofitable levels and why they are constrained in their investment decisions. Empirical evidence points to different explanations: cost of learning and access to information, insufficient education, risk, credit constraints, non-convex production technologies, and behavioral patterns that are inconsistent with standard neoclassical models. Currently, one of the major challenges in formulating policies that foster productive investments among the poor, seems to be to disentangle the effects of scale, credit constraints, and the lack of insurance mechanisms.
This thesis seeks to shed further light on the relative role of these three constraints. In the context of rural India, it analyzes what production and investment decisions households take and how important risk and credit constraints as well as scale effects are in these decisions. Finally, it evaluates potential policy tools that could support households in overcoming these constraints.
Today, 33% of the world's poor live in India, the vast majority of them (80.5%) in rural areas. The economic structure of rural India is still dominated by agricultural production, and consequently, this thesis concentrates on agricultural production decisions and employment in agriculture.
In particular, this thesis addresses three questions in three individual papers: First, are farm households constrained in their crop choices by agricultural production risk and to which extent can India's public works program support households in overcoming this constraint? Second, how profitable is cattle farming in rural India at different levels of investment and which barriers do households face in reaching optimal investment levels? And third, can risk in agricultural wages explain limited investment in girls' education in the presence of intra-household substitution in household chores?
The first paper focuses on crop choice of farm households. It reassesses the stylized fact that households have to trade-off between returns and risk in their crop choice in the context of Andhra Pradesh, a state in the south of India. It then explores the effect of India's flagship anti-poverty program, the National Rural Employment Guarantee Scheme (NREGS) on households' crop choice using a representative panel data set. The NREGS guarantees each household living in rural India up to a hundred days of employment per year, at state minimum wages.
The paper shows theoretically, and empirically, that the introduction of the NREGS reduces households' uncertainty about future income streams because it provides reliable employment opportunities in rural areas independently of weather shocks and crop failure. With access to the NREGS, households can compensate income losses emanating from shocks to agricultural production. Households with access to the NREGS can therefore shift their production towards riskier but also more profitable crops. These shifts in agricultural production have the potential to considerably raise the incomes of smallholder farmers.
The paper concludes that employment guarantees can, similarly to crop insurance, help households in managing agricultural productions risks. It also argues that accounting for the effects of the NREGS on crop choice and profits from agricultural production affects the cost-benefit analysis of such a program considerably.
The second paper concentrates on the profitability of farming cattle in Andhra Pradesh.
The paper also uses a representative panel dataset, and examines average and marginal returns to cattle at different levels of cattle investment. It finds average returns in the order of -8% at the mean of cattle value. These returns vary across the cattle value distribution between negative 53% (in the lowest quintile) and positive 2% (in the highest). While marginal returns are positive on average, they also vary considerably with cattle value and breed. The paper shows that average and marginal returns are considerably higher for modern variety cows, i.e. European breeds and their crossbreeds, than for traditional varieties of cows or for buffaloes. It also shows that cattle farming becomes most profitable at minimum herd sizes of five animals, due to decreasing average labor costs with increasing herd sizes.
The results of this paper suggest that cattle farming is associated with sizable non-convexities in the production technology and that substantial economies of scale, as well as high upfront expenses of acquiring and feeding high-productivity animals, might trap poorer households in low-productivity asset levels. The fact that wealthier households and households with lower costs to access veterinary services are more likely to overcome these barriers, supports this idea.
The second paper concludes that cattle farming might well generate positive returns for households in rural India, but that most households seem to operate at unprofitable levels. This could also explain the apparent paradox between widespread support of cattle farming through agricultural policy interventions and negative returns to cattle, as stressed in recent works. It argues that policy interventions that target productive assets will only be beneficial if transfers are high enough to allow households to overcome these entry barriers.
The third paper concentrates on the effect of risk on the productive decisions of households, and analyzes the effect of wage risk in agricultural employment on women's labor supply and time allocated to home production. It seeks to understand the extent to which risk raises labor supply of women to levels that can become harmful for other members of the household. The hypothesis is that in the presence of intra-household substitution effects -- for instance in the performance of household chores -- increased female labor supply might have negative effects on the time allocation of girls. If women have less time available for home production and childcare, and such activities can only be foregone at high cost, they might be forced to take older girls out of school or to cut down on the time these girls study at home in order for them to fill in for these tasks.
The paper uses cross-sectional data on the time allocation of different household members and predicts wage risk at the village level as a function of the historical rainfall distribution and a village's share of land that is under irrigation. The results show that wage risk affects the time allocation of women, increasing their labor supply and reducing the time they allocate to home production. Wage risk also increases the time girls spend on household chores and reduces their time in school. Because the observed effect of wage risk on girls' time allocated to household chores corresponds very closely to the effect observed for women, it seems plausible to attribute it to intra-household substitution effects. The observed effect of risk on girls' school time, however, is greater than the observed effect of risk on the home-production time of girls. This can be due to two reasons: First, in the presence of intra-household substitution effects, shocks in wages will not only increase female labor supply but also girls' time on household chores. And the model predicts that risk-averse households invest less in education when future school time becomes uncertain, because future school time affects the returns to current schooling. Second, if school attendance is indivisible, then girls might be forced to drop out of school temporarily or even permanently.
The paper then simulates the effect of the NREGS on the time-allocation decisions of working women and school-age girls. The results suggest that the NREGS could increase the time working women spend on household duties, because it reduces uncertainty regarding future earnings, and alleviates the need to accumulate savings. Thereby, the NREGS would reduce the pressure on girls to perform household tasks and allow them to increase the time they spend in school or studying by 6 minutes daily.
Wit these findings, this thesis contributes to a better understanding of the choices poor households in rural India face in their day-to-day decision making, and offers insights into what policies could support households in escaping poverty, and interrupt its inter-generational transmission.
In modern CMOS technology, process variations have significantly increased impact on the circuit behavior with continuously scaled transistor sizes. Manufactured devices tend to have different performances due to parameter variations during manufacturing and
in the operating context. Conventional tests generated regardless of variations could fail to rule out devices with low performance and even functional failure caused by extreme variations; the unreliability in shipped products is in turn raised. To tackle the problem, many existing test approaches have focused on identifying and testing a number of critical paths in the circuit, and aimed at the efficiency of the searching process. However, the statistical circuit model, which better describes the circuit timing behavior under variations, is not yet sufficiently investigated and employed by existing testing methodologies.
This thesis work proposes Opt-KLPG and MIRID, which can be utilized by a statistical delay testing flow. Opt-KLPG—a K Longest Paths Generation (KLPG) algorithm for optimal solutions under memory constraints—can pin-pointedly generate tests for small delay defects, which are common small timing deviations under process variations, based on the traditional KLPG algorithm. In contrast to KLPG, Opt-KLPG guarantees the optimality of the solution (the K longest sensitizable paths indeed). MIRID is a mixed-mode timing-aware simulator, incorporating effects of power-supply noise and combining an event-driven logic simulation engine with interfaces to provided electrical models. MIRID aims at evaluating delay tests in presence of process variations efficiently yet accurately, by performing logic simulation at the gate level while determining the gate delays using simplified electrical modes. The electrical models applied by the simulator focus on the IR drop effect. Electrical parameters mainly contributing to the effect
are incorporated into the model. The simulator is generic and flexible to be adapted by modifying the interfaces with minor effort. Both applications were verified in various aspects by experiments for academical/industrial circuits, and turned out to have satisfiable effectiveness and performance.