Rozprawy doktorskie na temat „Failures”

This thesis aims to give an understanding of what is behind a failure in a startup industry. To understand why failures are needed for a success, the serial entrepreneur process has to be clarified at an individual level. In the failure process, under analysis are the main phases of turning a failure into a success and the outcomes which should be used as the next venture foundations. This study also aims to give basic tools for entrepreneurships on how to proceed after a failure at a personal level so that the entrepreneurs would be able start a new venture having a positive experience from the last failure. The study begins with a literature review in which concepts of entrepreneurial learning and theoretical failure process model are presented. This created model is then tested in the empirical part. The method used in this study is done as an abductive approach using exploratory research design with a cross-sectional study method to collect and analyze qualitative data. The data in the empirical part has been collected with face-to-face and telephone interviews with professional serial entrepreneurs. The theoretical failure process model created in the literature review part was successfully tested in the empirical part. This process model could be used as the first step in any failure analyses as a tool for an entrepreneur or a manager. Going forward is much easier after analyzing the true reasons behind a failure. Finding root causes for a failure has provided learnings which are key tools for the future. The scientific results of this study show that every entrepreneur that was interviewed has had multiple setbacks as failures during their career. However, they have managed to separate their professional and private lives so that if and when a failure has happened, financial, social and physical costs have been less significant. When these negative costs have been minimal ones, the entrepreneurs have had no or only minor grief before being able to analyze true reasons behind a failure and gaining learnings for the next venture. Learning from past failures, they have been able to avoid similar mistakes happening again. Furthermore, low grief has allowed for the recovery time from failures to reduce significantly. The main managerial finding was that internal motivation is one of the root causes behind the entrepreneur having strength and motivation to continue despite failures. The internal motivation for their actions follows every step from starting a venture to failure analyses, all the way to learning and continuing to the next venture. In some cases, when that motivation was lost, even partly, entrepreneurs were noted to exit from that venture. The purpose of this study was to give understanding of why a failure should be accepted as a natural and sometimes needed, but not wanted, step for learning in a long perspective. The purpose was not to give detailed tools for every reasons behind failure, but this work will rather provide basic tools on how to proceed if a failure happens. If the failure acceptance was wider, the outcome would be beneficial on three different levels. To understand the reasons behind needing failures for success, we need to focus on the entrepreneur’s failure process at an individual level. After understanding that, the process can be scaled up to company and further to community levels.

The purpose of this essay is to propose a comprehensive legal theory of implementation allowing for a deeper understanding of the failures of contemporary Public Administration. Such a theory requires its proper methodology, which is, In fact, the missing link between administrative law and the so-called new sciences. The thesis takes the view that the systemic approach satisfies the above requirements, for it makes possible the broader concepti6n of law, viewed within Its social context. It also makes salient the decision-making element inherent in the implementation process. In this way, it enables the researcher to identify and interrelate important but latent factors of implementation failure, neglected or even overlooked by purely legal or purely empirical implementation studies. This deeper understanding of implementation, drawn from the relevant theoretic systemic models, is a necessary prerequisite for a sound policy making, avoiding the pitfalls of implementation failure. On the other hand, the usefulness of the proposed comprehensive legal study of implementation is shown in the Second Part of the thesis. For this purpose, a characteristic case of administrative failure has been selected and analyzed on the basis of the relevant theoretical model proposed in Part One. The case refers to the failure of urban policy in Greece as expressed in the phenomenon of unauthorized development. It is a case worth studying, since the failure is due to a multiplicity of factors other then the relevant legislation (statute of 17.7.1923), which is of a remarkable quality. The models and findings of the study can be applied to any case of implementation failure, thereby facilitating not only diagnosis but prevention of failures as well.

This dissertation research attempts to explore efficient algorithms and engineering methodologies of analyzing the overall reliability and availability of networks integrated with software failures and hardware failures. Node failures, link failures, and software failures are concurrently and dynamically considered in networks with complex topologies. MORIN (MOdeling Reliability for Integrated Networks) method is proposed and discussed as an approach for analyzing reliability of integrated networks. A Simplified Availability Modeling Tool (SAMOT) is developed and introduced to evaluate and analyze the availability of networks consisting of software and hardware component systems with architectural redundancy. In this dissertation, relevant research efforts in analyzing network reliability and availability are reviewed and discussed, experimental data results of proposed MORIN methodology and SAMOT application are provided, and recommendations for future researches in the network reliability study are summarized as well.

The economical importance and value of small businesses is today recognized by scholars as well as government institutes. The small business does not only contribute with a great amount of entrepreneurial activity and innovations but also as a significant tool in creating jobs. The statistics are however displaying a negative trend in the development of small businesses with over 350.000 – 400.000 business closures every year in UK. In Sweden 35,000 new enterprises entered the market in 2001 but only 62% were still active in 2004.

There are two major factors from which all other explanations are derived from when discussing why a company fails which is the external and internal factor. From the failure model created by Sharma and Mahajan and supported by other researchers, it is known that the problem initiating the failure may have been caused by uncontrollable factors. However the most significant factor behind a failure is derived from insufficient and ineffective management in the strategic process.

In order to understand how and most importantly why the top-managers decisions and actions contributes to a business failure the study focused on exploring the strategic process in numerous of failure cases of small businesses. This understanding is further strengthened by considering the limitations and resistances in the strategic process. There is also a link between the crisis management and strategic management which further provides with valuable insights of the process. Four different small businesses were therefore investigated in the report through an inductive and semi structured approach to explore the contexts of the failures in-depth. From the analysis of the empirical data collected from the top-managers and other employees, owners or managers evidence were collected to study the top-managers contribution to the failure.

The most significant contributing factor found in the business failures were the inefficient internal and external assessments. This was further found to be directly linked to the inadequate knowledge and experience possessed by the top-manager and his staff. Nepotism was also a factor that was found to be a very contributing source to the inadequate assessments. The managers staffed by the top-manager possessed a close relationship with the top-manager and may have been hired due to this reason and not based on the required knowledge which was proven to have a significant impact on all the studied cases.

Fatigue is a well known failure mode in engineering that can have catastrophic consequences, such as loss of human life. Thus design against fatigue failure is very important. There are many sources of scatter present in fatigue, for instance; the difference in load in-between users of a product, material scatter and scatter in the production. The material scatter will be studied in this thesis. In order to quantify the material scatter, experiments have to be performed. Both finite life tests, i.e. experiments at a constant stress levels where all specimen fail and the number of cycles to failure is stored, and fatigue limit tests, experiments where some experiments are run-outs and some experiments fail, have to be performed. The SN-space contains both the finite life part and the fatigue limit part. In order to model the material scatter, the Weakest Link (WL)-integral can be used. This integral, which was derived by Waloddi Weibull at KTH, takes the entire volumetric stress distribution into account. The outcome from this integral is a fatigue failure probability for a specimen or a structure. Thus if this integral is used a structure is designed with respect to a fatigue failure probability instead of a peak stress. Such a peak stress, or hot-spot stress, is related to the fatigue limit and is typically reduced by a safety factor. In paper A fatigue limit tests performed on a custom-made specimen with two notches of different size are presented. The predictive capabilities of the weakest link integral were studied here, where the WL-model was fitted to the experimental outcome in both notches separately and then to both notches simultaneously. It was observed that the WL-integral is in good agreement with the experimental outcome when fitted to the experimental outcome in one notch, but poor when fitted to both notches, The weakest link integral was evaluated at the specimen surface area and as a volumetric phenomenon in paper B. The conclusions in this paper was that the area and volume formulation of the WL-integral show similar results. A new model for the entire SN-space, the PES-model was analyzed in paper C. Here, an equivalent stress measure (a scalar stress value) was introduced in order to have the same stress measure for finite life and the fatigue limit regime. The investigated equivalent stresses were; the point stress (largest occurring stress value), the gradient adjusted point stress (largest occurring stress value reduced with the stress gradient), the area stress (an effective measure of the surface stresses using the weakest link) and the volume stress (a similar measure that summarize the volumetric stresses). It was observed that the choice of equivalent stress had a small effect for finite life both a large effect at the fatigue limit regime. In paper D a model that combines two failure mechanisms is presented, the DS-model. This model combines a defect based model, D, that is taken to be the weakest link integral (both area and volume versions) with a stress based model, S, taken to be the normal distribution where the stress measure used is either the point stress or the gradient adjusted point stress. It is assumed that the two failure mechanisms are independent. It was observed that, the D-model was dominating for low failure probabilities and the S-model for high failure probabilities. In order to study the experimental scatter in another way, the estimated fatigue failure locations were studied in paper E. The stress was then evaluated and the estimated fatigue failure sites and the local failure probability could be estimated. In order to better understand the spatial scatter in the estimated fatigue failure sites a modified stress gradient was used. Further, experiments where fatigue failure could occur in both notches were performed. It was seen that the spatial scatter was large, in terms of location and in stress. None of the fatigue limit models could describe the experimental trend from the competing fatigue failure site experiments. The effect of random defect is studied in paper F. In this paper defects of different size, which are treated as circular cracks, are placed at random positions in the specimen. A fatigue crack growth analysis is performed for each crack and thus the fatigue life is obtained. The main conclusion in this paper was that the computed fatigue crack growth life does not agree with the experimentally found fatigue life.

QC 20121026

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Coordination failures are often said to play an important role in business cycles. If agents’ incentives of taking a given action depend on the amount of other agents expected to take the same action, coordination failures can often arise. Firms may not invest because they do not expect others to invest, confirming their initial expectations. Similarly, banks may not lend because they do not expect others to lend. This dissertation analyzes different environments in which crises arise as a result of coordination failures. The first chapter analyzes an economy that is subject to a dynamic coordination problem. Because of aggregate demand externalities, firms’ incentives to increase their production depend on expected demand, which in turn depends on the amount produced by other firms. The problem is dynamic since firms do not take investment decisions at the same time, implying that a firm deciding today is trying to forecast what other firms will decide in the future. This opens the possibility of dynamic coordination traps: firms do not invest today because they do not believe others will invest tomorrow, generating lower incentives for firms to invest at future dates. This chapter focuses on the following questions: In economies subject to dynamic coordination traps, what is the optimal stimulus policies? Should policy makers provide higher incentives to production in times of low economic activity? The answer is that a constant subsidy implements the first-best in an economy where beliefs are endogenously determined. The reason is that, although it is harder to coordinate in times of low economic activity, agents are naturally more optimistic about the future in times of poor economic activity and reasonably good fundamentals. This optimism arise from the fact that in bad times negative shocks do not change the level of economic activity, while positive shocks may end a recession. The second chapter proposes a model to study unusually deep financial crises. Previous empirical work has found that financial crises are very deep and persistent on average, but there is a lot of heterogeneity across different episodes. Some financial crises feature a very distressed financial sector, but little distress on the real sector, while others are real macroeconomic disasters. In light of this evidence, I propose a model in which there is a highly non-linear feedback between the real and the financial sector. Disaster episodes arise from the dynamic interaction of two frictions: coordination frictions and financial frictions. When banks have weak balance sheets they do not intermediate much capital. This causes firms to get trapped in a self-reinforcing regime with low aggregate demand, which ends up provoking further damage to banks’ balance sheets. I use the model as a laboratory to study unusually deep financial crises and the effects of some policies. It is shown that the effects of disasters go far beyond what we observe during those episodes: they imply very low asset prices, economic growth and welfare, even in good times and when their probability is very small. Policies that protect the financial sector from those episodes can be very beneficial. Moreover, higher risk-taking in bad times may improve economic growth, welfare and financial stability. The third chapter studies the policy trade-off of a regulator that wants to avoid coordination failures, but at the same time does not want to generate distortions arising from moral hazard. Banks have investment opportunities with an expected return that depends positively on the amount of other banks undertaking similar investments, opening room for coordination failures. At the same time, banks may risk-shift to projects with smaller expected return but higher volatility. By providing guarantees in case of failures, a regulator can enhance coordination, but that leads banks to switch to worse projects. It is shown that in some states a regulator will provide no guarantees, even if it that means allowing a coordination failure to happen. Moreover, the possibility of risk-shifting reduces the amount of guarantees needed to avoid a coordination failure.
Com frequência argumenta-se que falhas de coordenação têm um papel importante no ciclo de negócios. Se os incentivos dos agentes a realizar determinada ação depende da quantidade esperada de outros agentes que tomarão a mesma ação, falhas de coordenação podem acontecer. Empresas podem não investir porque não esperam que outras empresas irão investir, confirmando suas expectativas iniciais. De maneira similar, bancos podem não conceder empréstimos porque eles não esperam que outros bancos irão fazer o mesmo. Esta tese analisa diferentes ambientes onde crises surgem como o resultado de falhas de coordenação. O primeiro capítulo analisa uma economia que está sujeita a falhas de coordenação dinâmicas. Por causa de externalidades de demanda agregada, os incentivos para uma dada firma aumentar sua produção dependem da demanda esperada, que por sua vez depende da quantidade produzida por outras firmas. O problema é dinâmico porque as firmas não tomam decisões de investimento ao mesmo tempo, implicando que uma firma tomando decisões hoje está tentando prever o que outras firmas decidirão no futuro. Isso abre a possibilidade de falhas de coordenação dinâmicas: firmas não investem hoje porque elas não acreditam que outras firmas investirão amanhã, gerando incentivos menores para outras firmas investirem no futuro. Este capítulo foca nas seguintes questões: Em economias sujeitas a este problema de coordenação dinâmico, qual a política de estímulo ótima? O governo deveria prover mais estímulos em épocas de baixa atividade econômica? A resposta é que um subsídio constante implementa o ótimo nesta economia. O motivo é que, embora seja mais difícil coordenar em tempos de baixa atividade, os agentes estão naturalmente mais otimistas sobre o futuro em tempos de baixa atividade e fundamentos razoavelmente bons. Este otimismo surge do fato que em tempos ruins choques negativos não alteram o nível de atividade econômica, mas choques positivos podem acabar com uma recessão. O segundo capítulo desta tese propõe um modelo para estudar crises financeiras mais severas que o usual. Trabalhos empíricos prévios mostram que, em geral, crises financeiras são muito profundas e persistentes, mas também que há muita heterogeneidade entre diferentes episódios. Algumas crises financeiras causam enormes danos no sistema financeiro, mas pouco dano no setor real, enquanto outras são verdadeiros desastres macroeconômicos. À luz desta evidência, esta tese propõe um modelo onde há um feedback extremamente não linear entre o setor financeiro e o setor real. Desastres surgem através da interação dinâmica de duas fricções: fricções de coordenação e fricções financeiras. Quando os bancos estão com problemas em seus balanços, eles optam por intermediar menos capital. Isso leva as firmas a entrar em um regime com baixa demanda agregada, que causa ainda mais dano ao capital dos bancos. Este modelo é utilizado como um laboratório para estudar crises financeiras muito severas e o efeito de algumas políticas. É mostrado que os efeitos de desastres econômicos vão muito além do que observamos durante estes episódios. Eles levam à queda dos preços de ativos, baixo crescimento e perdas de bem-estar, mesmo que a probabilidade destes eventos seja muito pequena. Finalmente, quando os bancos tomam mais risco em tempos ruins, podemos ter um aumento de crescimento, bem-estar e estabilidade financeira. O terceiro capítulo estuda o trade-off enfrentado por um regulador que quer evitar falhas de coordenação, mas ao mesmo tempo não quer gerar distorções que surgem por conta de risco moral. Os bancos possuem oportunidades de investimento cujo retorno esperado depende positivamente da quantidade de outros bancos investindo em projetos similares, abrindo espaço para a possibilidade de falhas de coordenação. Ao mesmo tempo, bancos podem escolher investir em projetos com menor retorno esperado e maior volatilidade. Ao prover garantias em caso de falha de um banco, um regulador pode melhorar a habilidade que estes têm de coordenar, mas ao mesmo isto pode levar os bancos a tomarem risco excessivo. É mostrado que em alguns estados o regulador não proverá garantias, mesmo que isso implique permitir que uma falha de coordenação aconteça. Ainda, a possibilidade dos bancos tomarem risco excessivo reduz a quantidade de garantias necessárias para evitar uma falha de coordenação.

This thesis consists of two essays on IPO failures around the world. IPO failures are defined as IPO withdrawals (Essay 1) or delistings of recent IPOs for negative reasons (Essay 2). A common theme that runs through the two essays is the importance of institutional and cultural characteristics in explaining cross-country differences in IPO failures.

Rock fall failure comprises fracturing through zones of intact rock, known as rock bridges, and kinematic release along discontinuity surfaces. Understanding controls on magnitude – frequency relationships of rockfalls, and their associated failure characteristics aids susceptibility analysis and interpretation of pre-failure deformation. For failure to occur, these rock bridges must have been weakened, with this damage accumulation driven by a suite of weathering processes. This thesis aims to explore the spatial and temporal controls on weathering induced strength degradation and its subsequent influence on the mechanics of rockfall detachment. Within this, it examines the role of gravitational ambient stress, as dictated by slope topography and rock mass structure, which recent research suggests influences the efficiency of weathering processes. The project integrates field observations, analogue experiments and numerical modelling over varying spatial scales. Terrestrial laser scanning and gigapixel photography are combined to forensically map rock bridge attributes within rockfall detachment surfaces. The role of slope geometry and rock mass structure in concentrating stress is assessed via conceptual finite element models. Finally, samples are subjected to stress conditions induced by the slope structure and environmental conditions in a series of weathering analogue experiments. Together, these results indicate that weathering significantly reduces intact rock strength with areas of stress concentration purely a mechanical control on rockfall release rather than a temporal control on weakening. Weaker rock is characterised by substantial post-peak strength, which requires multiple stages of brittle fracture before ultimate failure occurs. This in turn influences the stages of failure required through rock bridges before final failure, with this number of rock bridges dependent on rockfall size. Mechanically, failure mode is dependent on rock bridge proportion, distribution and location for individual rockfalls. A conceptual model describes magnitude-frequency characteristics and the observable pattern of pre-failure deformation expected for different stages of weathering.

One of the objectives of this study is to develop a methodology, together with a set of software programs that evaluate, in a power system, the risks of catastrophic failures caused by hidden failures in the hardware or software components of the protection system. The disturbance propagation mechanism is revealed by the analysis of the 1977 New York Blackout. The step-by-step process of estimating the relay hidden failure probability is presented. A Dynamic Event Tree for the risk-based analysis of system catastrophic failures is proposed. A reduced 179-bus WSCC sample system is studied and the simulation results obtained from California sub-system are analyzed. System weak links are identified in the case study. The issues relating to the load and generation uncertainties for the risk assessment of system vulnerabilities are addressed. A prototype system - the Hidden Failure Monitoring and Control System (HFMCS) - is proposed to mitigate the risk of power system catastrophic failures. Three main functional modules - Hidden Failure Monitoring, Hidden Failure Control and Misoperation Tracking Database - and their designs are presented. Hidden Failure Monitoring provides the basis that allows further control actions to be initiated. Hidden Failure Control is realized by using Adaptive Dependability/Security Protection, which can effectively stop possible relay involvement from triggering or propagating disturbance under stressed system conditions. As an integrated part of the HFMCS, a Misoperation Tracking Database is proposed to track the performance of automatic station equipment, hence providing automatic management of misoperation records for hidden failure analysis.
Ph. D.

Companies can draw valuable lessons from their failures, and use them for their improvementwork. A positive failure culture is however a necessary precondition. High reliabilityorganisations (HRO) are known for their effective way of tackling and using failures aspotential for improvements. The aims of the study were to evaluate failure culture in an ISO9001 certified company, after HRO standards and thereby withdraw improvementpossibilities. The study was conducted through a deductive quantitative method using asurvey for data gathering. With approximately 30 percent response rate, and using statisticaltests, the failure culture of the company was evaluated. The results showed that the companyis not currently reaching a failure culture within HRO standards, but nevertheless has positivetendencies rather than negative. Lastly, improvement possibilities were discussed andsuggestions for further research were given.

2020-06-26

Retrospective memory is the cognitive function associated with recalling details from the past, (e.g., someone’s name) whereas prospective memory is the cognitive function associated with recalling an intention or plan in the future (e.g., attending a meeting). There is an interesting hypothesis that states prospective memory failures (e.g., forgetting about a meeting) tend to be interpreted as personality flaws while retrospective memory failures (e.g., forgetting someone’s name) tend to be interpreted as simply memory breakdowns. Recent research has supported this hypothesis, however little is known about the properties of the memory failures that might influence the biases in interpretations or the underlying cognitive processes of the effect. Three experiments were designed to address these important issues. The first experiment examined sociality and importance of the memory failures as potential properties influencing interpretations. Participants were presented with memory failure vignettes that varied on these dimensions, and the bias towards personality flaw interpretations of prospective memory failures only occurred memory failures were social in nature. Furthermore, the effect was slightly weakened by the perspective from which the vignettes were written (the participant’s perspective). The second experiment developed a priming procedure that successfully induced a sense of self-perceived memory fallibility by requiring participants to generate examples of prospective and retrospective memory failures they had committed. In the third experiment this priming procedure was implemented prior to vignette interpretations with the objective of manipulating the interpretations bias. The results of Experiment 3 indicated that the priming manipulation reduced differences in the interpretations participants offered for prospective versus retrospective memory failures, particularly in terms of the seriousness, personality flaw, and poor memory interpretations of prospective failures. These results suggest that the priming procedure facilitated empathy the protagonist, and in this way reduced this interpretation bias.

Rock slope failures leading to rock falls and rock slides are caused by a multitude of factors, including seismic activity, weathering, frost wedging, groundwater and thermal stressing. Although these causes are generally attributed as separate causes, some of them will often act together to cause rock slope failures. In this work, two of the above factors, seepage of water through cracks and crack propagation due to the after effects of blasting are considered. Their combined impact on the development of rock falls and rock slides is modeled on ANSYS workbench using the Bingham Canyon mine slope failure of 2013 as a case study. Crack path modeling and slope stability analysis are used to show how a combination of crack propagation and seepage of water can lead to weakening of rock slopes and ultimate failure. Based on the work presented here, a simple approach for modeling the development of rock falls and rock slides due to crack propagation and seepage forces is proposed. It is shown how the information from remote sensing images can be used to develop crack propagation paths. The complete scope of this method involves demonstrating the combination of basic remote sensing techniques combined with numerical modeling on ANSYS workbench.

Failure Modes and Effects Analysis (FMEA) is a Six Sigma tool for identifying, analyzing and prioritizing failures and solutions. FMEA is widely used in many different industries worldwide. The FMEA model is neither easy to learn nor easy to use. Effective FMEA automation has been an elusive goal for some time. The scope of meaningful FMEA automation has been limited to specific proprietary or academic application domains where substantial time and effort have been invested. Commercially available FMEA software packages do little more than reduce clerical effort. There has been no published research on the usability of FMEA. Most of the recent FMEA research has applied various artificial intelligence technologies. The vast majority of FMEA research has been directed toward manufactured products rather than information systems. The author has examined the use of FMEA for software development. The author's goal for this dissertation was the creation of a usable failure analysis matrix (FAM) model for prioritizing solutions to failures in information systems. The two-dimensional F AM worksheets are smaller than the linear FMEA worksheets, requiring less scrolling. The F AM is an alternative method to help identify the most important potential failures or failures and help prioritize alternative solutions using approximate expected costs. This new tool, implemented in Excel, provides integrated data entry and reporting. The F AM may be used without having detailed information. The author validated four usability attributes for the F AM: usefulness, ease of use, ease of learning, and satisfaction. The validation process employed expert reviews, usability testing, and a usability questionnaire. The final mean value of 5.30 for usability questionnaire items compares favorably with a neutral value of 4. The F AM underwent expert reviews with reviewers from three different domains of expertise: usability, FMEA, and Six Sigma. Usability test subjects were 20 GE Industrial Systems information systems professionals. The test subjects applied the F AM to real information systems failures. The author has improved professional practice by applying usability engineering to a problem analysis tool for software development. Expert reviews and usability testing both proved to be applicable to the design of the F AM. The expert reviews resulted in the inclusion of several important attributes of the FAM. The usability testing resulted in shorter task completion times and less severe usability problems.

Developers often write test cases that assert the behaviour of a web application from an end-user’s perspective. However, when such test cases fail, it is difficult to relate the assertion failure to the faulty line of code. The challenges mainly stem from the existing disconnect between front-end test cases that assert the DOM and the application’s underlying JavaScript code. We propose an automated technique to help developers localize the fault related to a test failure. Through a combination of selective code instrumentation and dynamic backward slicing, our technique bridges the gap between test cases and program code. Through an interactive visualization, our approach, implemented in a tool called Camellia, allows developers to easily understand the dynamic behaviour of their application and its relation to the test cases. The results of our controlled experiment show that Camellia improves the fault localization accuracy of developers by a factor of two. Moreover, the implemented approach incurs a low performance overhead.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate

Thesis: S.M. in Management Research, Massachusetts Institute of Technology, Sloan School of Management, 2015.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 61-72).
Most internet business models today are positioned as platforms that connect two or more groups of users. From online social networking to electronic retail, we find that multi-sided platforms are penetrating consumers' lives more deeply with time. There has been significant amount of research around what it takes to establish a successful platform and the strategies to compete in a platform market. However, there is a significant research gap in a systematic analysis of the spectacular failures that platform markets have witnessed over the last couple of decades. This paper studies these failures and derives lessons from them, in order to add a unique and much needed perspective to the various platform success stories. After conducting a comprehensive literature review to determine the various factors that are critical in determining a platform's success, this paper defines a systems model to analyze platforms. This model is then used as a base for analyzing failed platforms, picked from three different software niches - Online Social Networks, Question & Answer Platforms and Instant Messengers. The analysis of each platform concludes with isolated primary points of failure. It is found that the root causes behind platform failure vary across market niches and timelines. For instance, the failure of an online social network in the early 90s (Myspace) is found to be different from the failure of such a platform today (Google Plus). A recurring theme across the analyzed failures was the need to focus on Design and User Experience, which has been identified as a new axis of differentiation in platform markets. User experience is found to evolve over time with changing consumer expectations. This underscores the need for platforms to keep in sync with evolving consumer needs. This, in turn, implies that platforms need to be agile to respond quickly to market shifts and should look to leverage community innovation by opening the platform. Lastly, envelopment has been identified as a potent strategy to compete in platform markets and to trounce well-ensconced competitors.
by Harsh Vardhan.
S.M. in Management Research

Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2015.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 97-103).
This thesis contributes to the theoretical literature that studies the macroeconomic implications of financial frictions. It develops frameworks to address different financial market failures, and evaluate preventive policies to mitigate the vulnerability of the economy to costly systemic crises. First, it identifies a credit risk (fire sale) externality that justifies the macroprudential regulation of short-term debt to mitigate the probability of systemic bank runs. Without regulation, banks do not internalize how their funding decisions affects the terms at which other market participants can obtain credit. The formal welfare study conducted, provides a general equilibrium notion of systemic risk that captures both fundamental insolvency and illiquidity risk. It also connects this measure with the optimal Pigouvian (corrective) tax. Second, it shows that liquidity crises may arise as the result of endogenous information panics. It finds that collective ignorance is welfare maximizing but it is fragile, susceptible to self-fulfilling fears about asymmetric information. Adverse selection may thus obtain in equilibrium, sustained by negative aggregate expectations. The mechanism that gives rise to multiple equilibria is robust to the introduction of noisy private signals, and warrants the regulation of information acquisition for rent-seeking (speculative) motives. Finally, it demonstrates the limitations of unconventional credit easing policies to stimulate lending during market-freezes. With inter-temporal investment complementarities, credit to non-financial firms may be curtailed as the result of dynamic coordination failures. Interest rate cuts mitigate coordination risk, but increase the average duration of credit market freezes when the productivity of capital is high. Capital injections in the banking sector, or direct lending to non-financial firms, are completely ineffective, because reductions in deposits from households crowd out government spending. In contrast, government guarantees improve welfare by reducing strategic uncertainty.
by Diego Feijer.
Ph. D.

Information systems (IS) are used almost everywhere around us and we cannot even conceive of a world without computerised systems. IS support essential functions in most areas and levels of society. These include education, business, leisure, and medical and scientific areas. Moreover, IS add to the competitiveness of companies and support the continuous change that takes place in business and its environment. Literature frequently reports on Information systems that fail or are abandoned in many domains and in many countries. Often IS are seen by users as underperforming, failing to meet expectations and not delivering value to customers. In order to reduce IS failures numerous studies have been conducted resulting in solutions being offered to improve the situation. Post-project reviews are often used to learn from mistakes. Social sciences regularly use narrative analysis methods to analyse stories to understand the experiences of people in settings such as psychology and education. This study borrows from the social sciences and proposes the use of narrative analysis in investigating IS failure research. A case history was identified in which IS stakeholders were asked to share their experiences regarding the development and use of the IS. Three narrative analysis approaches were applied in this study to analyse the accounts of the stakeholders taking into account the perspectives of multiple user groups. This was done in order to study the thesis statement: narrative analysis methods can be useful to make sense of Information systems’ failures. A multi-perspective framework for analysing IS stakeholders’ accounts was constructed, during the study, which could be used by developers to gain insight from the users of previous systems in order to learn from mistakes for subsequent systems. It is shown in this qualitative study, where narrative approaches were followed to gather, analyse and interpret the rich, multi-voiced and incoherent stories of IS stakeholders, that each approach helps to make sense from the accounts of stakeholders in different ways and highlight important elements. It is shown that narrative analysis methods that were used in this study can produce deeper insights into the experience of involved stakeholders. The insights obtained from applying narrative methods can be used for internal learning within organisations as well as externally within the discipline. It is shown in this study that all voices must be heard; the small stories of stakeholders should also be taken into account when listening to users. Reading between the lines reveals information that cannot be ignored if IS are to be developed to the satisfaction of all stakeholders. Indeed, systems become alive and take on a character of their own when the accounts are analysed on a deeper level and systems can therefore be designed in new ways that enable developers to address a wider set of constraints representing multiple groups of stakeholders. The contribution of this work is on more than one level. Information systems development practice can be influenced and enriched by gaining deeper insights that address the concerns of the diverse groups of stakeholders. The research methodology field of IS has also been impacted upon by the successful importing of methods from another domain and has thereby also given back to the discipline it has borrowed from. Narrative practice and theory can make use of the new insights gained in a new area of application, namely IS failures. The conclusion of this study is that narrative approaches and storytelling can be useful and applicable when investigating IS failures and improves the understanding of IS development and users’ concerns taking into account multiple perspectives of stakeholders.

The intent of this research and these is to describe the development of a series of charts and tables that provide the individual and cumulative probabilities of failure applying to the Weibull statistical distribution. The mathematical relationships are developed and the computer programs are described for deterministic and Monte Carlo models that compute and verify the results. Charts and tables reflecting the probabilities of failure for a selected set of parameters of the Weibull distribution functions are provided.

This work studies the consequences of a human-initiated targeted attack on the electric power system by simulating the detonation of a bomb at one or more substations in and around Washington DC. An AC power flow based transient analysis on a realistic power grid model of Eastern Interconnection is considered to study the cascading events. A detailed model of control and protection system in the power grid is considered to ensure the accurate representation of cascading outages. Particularly, the problem of identifying a set of k critical nodes, whose failure/attack leads to the maximum adverse impact on the power system has been analyzed in detail. It is observed that a greedy approach yields node sets with higher criticality than a degree-based approach, which has been suggested in many prior works. Furthermore, it is seen that the impact of a targeted attack exhibits a nonmonotonic behavior as a function of the target set size k. The consideration of hidden failures in the protective relays has revealed that the outage of certain lines/buses in the course of cascading events can save the power grid from a system collapse. Finally, a comparison with the DC steady state analysis of cascading events shows that a transient stability assessment is necessary to obtain the complete picture of cascading events in the aftermath of a targeted attack on the power grid.
M.S.
The modern day power system has been identified as a critical infrastructure providing crucial support to the economy of a country. Prior experience has shown that a small failure of a component in the power grid can lead to widespread cascading events and eventually result in a blackout. Such failures can be triggered by devastating damage due to a natural calamity or because of a targeted adversarial attack on certain points in the power system. Given limited budget to avoid widespread cascading failures in the network, an important problem would be to identify critical components in the power system. In this research an attempt has been made to replicate the actual power system conditions as accurately as possible to study the impact of a targeted adversarial attack on different points in the network. Three heuristics have been proposed to identify critical nodes in the network and their performance has been discussed. The case studies of cascading events have been performed on a synthetic power system network of Washington DC to achieve the actual system conditions of an operating power grid.

Companies have invested large amounts of money on information systems development. Unfortunately, not all information systems developments are successful. Software project failure is frequent and lamentable. Surveys and statistical analysis results underscore the severity and scope of software project failure. Limited research relates software structure to information systems failures. Systematic study of failure provides insights into the causes of IS failure. More importantly, it contributes to better monitoring and control of projects and enhancing the likelihood of the success of management information systems. The underlining theories and literature that contribute to the construction of theoretical framework come from general systems theory, complexity theory, and failure studies. One hundred COBOL programs from a single company are used in the analysis. The program log clearly documents the date, time, and the reasons for changes to the programs. In this study the relationships among the variables of business requirements change, software complexity, program size and the error rate in each phase of software development life cycle are tested. Interpretations of the hypotheses testing are provided as well. The data shows that analysis error and design error occur more often than programming error. Measurement criteria need to be developed at each stage of the software development cycle, especially in the early stage. The quality and reliability of software can be improved continuously. The findings from this study suggest that it is imperative to develop an adaptive system that can cope with the changes to the business environment. Further, management needs to focus on processes that improve the quality of the system design stage.

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada
Telemetry Prognostics is Failure Prediction using telemetry for launch vehicle and satellite space flight equipment to stop launch failures, launch pad delays, satellite infant mortalities and satellite on orbit failures. This technology characterizes telemetry behaviors that are latent, transient, and go undetected by the most experienced engineering personnel and software diagnostic tools during integration and test, launch operations and on orbit activities stopping launch pad delays, launch failures, infant mortalities and on orbit failures. Telemetry prognostics yield a technology with state-of-the-art innovative techniques for determining critical on-board equipment remaining useful life taking into account system states, attitude reorientations, equipment usage patterns, failure modes and piece part failure characteristics to increase the reliability, usability, serviceability, availability and safety of our nation’s space systems.

The goal of the research is to provide an overview of those factors that play a major role in structural failures and also to focus on the importance that bracing has in construction accidents. A temporary bracing system is important to construction safety, yet it is often neglected. Structural collapses often occur due to the insufficient support of loads that are applied at the time of failure. The structural load is usually analyzed by conceiving the whole structure as a completed entity, and there is frequently a lack of design or proper implementation of systems that can provide stability during construction. Often, the specific provisions and requirements of temporary bracing systems are left to the workers on the job site that may not have the qualifications or expertise for proper execution. To effectively see if bracing design should get more attention in codes and standards, failures which could have been avoided with the presence and/or the correct design of a bracing system were searched and selected among a variety of cases existing in the engineering literature. Eleven major cases were found, which span in a time frame of almost 70 years, clearly showing that the topic should get more attention. The case studies are presented in chronological order and in a systematic way. The failed structure is described in its design components and the sequence of failure is reconstructed. Then, the causes and failure mechanism are presented. Advice on how to avoid similar failures from happening again and hypothetic solutions which could have prevented the collapses are identified. The findings shows that insufficient or nonexistent bracing mainly results from human negligence or miscalculation of the load analysis and show that time has come to fully acknowledge that temporary structures should be more accounted for in design and not left to contractors' means and methods of construction.

Thesis (Ph. D.)--University of California, San Diego, 2006.
Title from first page of PDF file (viewed June 5, 2006). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 206-215).

This study investigates the factors that were important in the failure of 36 banks in 1997-2006. The study uses cross-section time series data from 81 banks and employs limited dependent variable models, a duration model and a dynamic panel data model in the analysis. The major concerns are to examine the determinants of banking failures by explaining the contribution of microeconomic and macroeconomic factors in Turkish banking system, to estimate the likelihood of banking failure and timing of failure, to analyze survival time path of failed and non-failed banks separately and to construct the degree of fragility of overall banking system. Furthermore, the determinants of bank profitability and the effects of bank-specific factors and macroeconomic conditions on bank profitability are analyzed by using dynamic panel data model.

Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1999.
Includes bibliographical references (leaves 55-56).
by Irina V. Abarinov.
S.B.and M.Eng.

The dataset is first analyzed on a basic level by looking at the correlations between number of measurements and average download speed for every day. Second, our PCA-based methodology applied on the dataset, taking into account many factors, including the number of correlated measurements. The results from each analysis is compared and evaluated. Based on the results, we give insights to just how efficient the tested methods are and what improvements that can be made on the methods.This thesis investigates the efficiency of a methodology that first performs a Principal Component Analysis (PCA), followed by applying a threshold-based algorithm with a static threshold to detect potential network degradation and network attacks. Then a proof of concept of an online algorithm that is using the same methodology except for using training data to set the threshold is presented and analyzed. The analysis and algorithms are used on a large crowd-sourced dataset of Internet speed measurements, in this case from the crowd-based speed test application Bredbandskollen.se.

The ultimate goal of the following master thesis is to identify specific mistakes in corporate governance practices that have led to colossal losses in financial derivatives trading departments, to draw lessons from these cases, and to propose possible solutions to prevent such behavior and the consequences that follow.

I have conceived, undertaken and published a body of work in Urology which has applied an evidence-based approach to different aspects with widely varying success in modifying the impact on treatment choices and outcome. On the positive side, the research work I have led has demonstrated that the era when death statistics could be used to the occurrence of benign prostatic hyperplasia was gone and that we had moved to an epoch where symptomatic disease and quality of life were the key issues. I have worked on the creation of the questionnaire-based approach necessary for evaluating the presence of various urological conditions for use in different populations clearly identified and quantified the extent and inter-relationships between the various benign urological conditions in communities. This work has made it quite clear that such benign conditions as benign prostatic hyperplasia, erectile dysfunction, incontinence, prostatitis and cystitis are remarkably common conditions world-wide in ageing populations. Since 1990, treatment options for men and symptomatic BPH have moved from an essentially surgical approach to an increasing introduction of pharmacologic options and less invasive approaches to disease management. The meta-analysis of the Phase III clinical trials of finasteride which I undertook, demonstrated that this drug was effective only in men with enlarged prostates and justified the biological approach taken in the development of this drug which was an inhibitor of 5-alpha reductase, the enzyme which converts Testosterone (T) to Dihydrotestosterone (DHT) the metabolite which made the prostate hyperplastic. I then demonstrated that serum PSA was a good indicator of prostate volume thus making identification of men who would most likely respond to this drug easily identifiable. Using this same dataset, I was able to demonstrate that finasteride reduced the risk of Acute Urinary Retention (AUR) and that it was superior to alpha-blockers, the other major class of drugs used to treat symptomatic BPH, in this regard. I designed the phase III trials of dutasteride, a new five-alpha reductase inhibitor, and the findings lay on the regression line demonstrated in the meta-analysis of finasteride and also had the identical effect on reducing the risk of AUR. I was able to develop a method of predicting individual risk of AUR in men who were diagnosed with benign prostatic hyperplasia.

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Coordination failures are one of the possible reasons why economies suffer during a recession and why they take long time to recover. This work studies a macroeconomic model with endogenous hazard rates that captures in a simple way the dynamic coordination problem and assess it quantitatively. We could find that, for the US economy, coordination failures have very small effects but very persistent.
As falhas de coordenação são uma das possíveis razões pelas quais as economias sofrem durante uma recessão e por que demoram para se recuperar. Este trabalho estuda um modelo macroeconômico que capta de forma simples o problema da coordenação dinâmica e o avalia quantitativamente. Encontramos que, para a economia dos Estados Unidos, falhas de coordenação têm efeitos pequenos, mas bem persistentes.

CI (Continuous Integration) is a software development practice which became more and more popular in last decade. Ericsson followed the trends and used CI several years. Because of the complexity of RBS (Radio Base Station) software few levels of CI have been implemented there. In RCS (RBS Control System) module CI there are many automatic JCAT (Java Common Auto Tester) test loops running every day and some of them failed. This thesis tries to find a way to classify these test failures automatically, so efficiency and lead time can be improved. Two methods are presented and investigated in this report, rule matching and machine learning. After analysis and comparisons rule matching approach is selected because it does not require huge effort in the initial phase and rule matched data can be used as labeled data for machine learning. This approach requires manual work to add new rules continuously but with correctly defined rules the accuracy is 100%, if the rule is general it can classify one type of issue including the ones which never happen before. One analysis system is designed and implemented, and only small update is required to the result report block of the CI flow. One matching example is showed and according to estimation this method could save many man hours every year.

In natural and manmade disasters, inadequate strategies to recover from satellite communication (SATCOM) failures can affect the ability of humanitarian organizations to provide timely assistance to the affected populations. This single case study explored strategies used by network administrators (NAs) to recover from SATCOM failures in humanitarian operations. The study population were NAs in Asia, the Middle East, Central Africa, East Africa, and West Africa. Data were collected from semistructured interviews with 9 NAs and an analysis of network statistics for their locations. The resource-based view was used as the conceptual framework for the study. Using inductive analysis, 3 themes emerged from coding and triangulation: redundancy of equipment, knowledge transfer, and the use of spare parts to service the SATCOM infrastructure. The findings showed that the organization's use of knowledge, and collaboration among NAs and nontechnical staff improved the organization's ability to recover from SATCOM failures. The implication of this study for social change was the reduced cost of satellite services due to the efficient use of the bandwidth. These savings can be channeled into the purchase of vaccines, shelter, and the improvement in the quality of water and sanitation for displaced persons in humanitarian disasters, which improve the organization's delivery of humanitarian services to the affected populations in the disaster.