We analyze an interdiction problem in which a nuclear-material smuggler can traverse the rail and road ports of entry (POEs) along the Mexican and Canadian borders of the United States. Our objective is to determine the optimal locations of a limited number of transparent and non-transparent assets so as to minimize the smuggler’s total probability of evasion, from origin to destination. We choose origins in Mexico and Canada and give the smuggler a diverse set of destinations to choose from. Our analysis aims to provide a complete prioritization and picture of the threat at Mexican and Canadian POEs, leading to insight into practical locations for transparent and non-transparent assets. / text

We analyze an interdiction problem in which a nuclear-material smuggler can traverse multiple transportation networks, wherein each edge has an indigenous probability of evasion. Our objective is to determine the optimal locations of a limited number of radiation detectors at United States ports of entry across multiple networks (maritime, road and rail) so as to minimize the smuggler's total probability of evasion, from origin to destination. We choose geographically diverse potential origins and give the smuggler freedom to move across and between transportation networks. Further, we consider two different models of smuggler behavior in this context. Our analysis aims to provide a complete prioritization and picture of the threat at all ports of entry, leading to insight into good practical locations for detectors. / text

Cell Broadcast (CB) is a possible technical realisation of a global emergency alert system. It is a technique used for sending short text messages to all mobile stations (MSs) in a defined geographical area. An potential effect of using CB is the increase in battery consumption of the MS due to the fact that an extra channel has to be used to make the service available even when the network is otherwise congested. Another part of the service which leads to a potential problem is making CB messages available in different languages. Investigating these problems is the objective of this thesis and the studies it includes. During the first part of the thesis, we measured the battery consumption of MSs in different modes of operation in order to analyse how CB affects the amount of current drained. The tests showed that battery consumption increased only slightly when CB messages were being received at the MS. Although some of the results can be, and are, discussed, we believe that CB would have a small effect on the power consumption of an MS, particularly in a context where it would be used for emergency warning messages only. This mentioned, it would however be wishful to confirm the conclusions further through the realisation of long-term testing. The second part of the thesis deals with the investigation of the MSs’ support for CB messages with different coding schemes. Based on the investigation’s result, we have come to the conclusion that in the long term the usage of different coding schemes on the same channel is preferred. However, the usage of one, global, emergency channel is hard to realise since that requires a standardisation between all countries. In our opinion this may be achieved first in the long run and until then, the usage of separate channels seems to be necessary.

In Sweden close to 500 people are killed and several thousands severely injured in traffic each year. This is one of the largest health problems for society in both Sweden and the whole world. In the cars of tomorrow will the main instrument panel and the centre console be screen-based instead of the current solution with “iron instruments” and other physical devices. This future driver environment opens for a flexible and situation-dependent usage of presentation resources. The purpose of this thesis is to explore these possibilities from a warning system perspective. The project had its main focus on designing warning system concepts using the HUD and vibrotactile information in a coordinated way based on established HMI principles. Another goal for this thesis work was to generate a functional concept for demonstration and evaluation in the virtual reality lab at the University of Linköping. The method of realization was divided into three phases – information gathering, concept generation and implementation. These phases are commonly used in design projects. This way of work supplies structure to the project and makes it possible to achieve an iterative design process. The information gathering involved a thorough theoretical study of HMI, interface design and warning design. A state of the art investigation was then conducted to find out how the warning systems, relevant to this thesis, are presented today. The concept generation was divided into two parts – warning system design and visual design. The Warning system design concepts were based on different combinations from a morphologic matrix and relevant theory. Consideration was also taken to when the systems are likely to be activated and which modality, or modalities, that then was suitable to use. The visual design concepts were developed by using creative product development methods and the iterative Simulator-Based Design (SBD) theory. After concluding the concept generation was the visual design results given functionality by programming software. The visual warning system were then integrated in the simulator software and fully implemented in the simulator cockpit at the university. The implemented warning systems were then evaluated by a pilot study conducted in the simulator. Test persons were invited to the VR-lab and given an introduction to the warning systems. They were then asked to drive a predetermined route with a number of different warning system conditions. These test results were later statistically analyzed and evaluated.

That an auditor brings good quality to the work he is performing is of great importance, not only for the company in question but also for its stakeholders. The information that the company disclose gets more credibility because of the auditor quality assurance. That the auditor tenure would affect the quality has been researched with different results, dependent on the legislation in the current country or region. In this paper we study how audit quality is affected of the audit tenure in Sweden. Based on research made in Belgium we have formulated hypothesis with factors that can affect the audit quality. Variables have been developed to measure the factor audit quality using GCW (going concern warning), audit fees, Big 4, the sale in the company and audit tenure. The focus in our paper is, weather the company has gotten a GCW or not, to see the relationship between audit tenure and auditor quality. We have investigated this by studying 19 506 bankrupted companies and 1 117 financially distressed companies. Our study has only been provided by primary data. Through analyses a relationship has been no defined between the tenure and the quality, with a number of explanatory variables. Our study explains that the auditor tenure in bankrupt companies, which tells us that there is no correlation between auditor tenure and audit quality. For the financially distressed companies there is no support for a result. / Att en revisor bringar god kvalitet till arbetet denne utför har en stor betydelse, inte bara för företaget i fråga utan även för dess intressenter. Informationen som företaget lämnar ut får på så vis större trovärdighet tack vare revisorns kvalitetssäkring. Att längden på revisionsuppdraget skulle påverka kvaliteten har det forskats om med olika resultat, utifrån vilket land den utförts i och vilken lagstadgande som råder i respektive land eller region. Vi har i uppsatsen valt att studera hur revisionskvaliteten påverkas av längden på revisonsuppdraget i Sverige. Utifrån forskning som utförts i Belgien har hypoteser utformats med faktorer som kan påverka revisonskvaliteten. Variabler har sedan tagits fram för att mäta faktorn kvaliteten på revisionen med hjälp av GCV, arvode, Big 4, omsättningen i företaget, antal anställda samt revisionsuppdragets längd. Vårt fokus i arbetet är att, utifrån om företagen fått en GCV eller inte, se sambandet mellan revisionskvaliteten och längden på revisionsuppdraget. Detta har vi undersökt genom att studera 19 506 konkursdrabbade företag och 1 117 finansiellt nödställda företag. Undersökningen har endast bestått av insamling av primärdata. Genom analysering har inget samband kunnat fastställas mellan längden på revisonsuppdraget och revisionskvaliteten med ett antal förklarande variabler. Undersökningen visar att längden på revisionsuppdraget i konkursdrabbade bolag inte har något samband med revisionskvaliteten. För de finansiellt nödställda företagen saknas stöd för resultatet.

Traditional communication channels like news channels are not able to provide spontaneous information about disasters unlike social networks namely, Twitter. The present research work proposes a framework by mining real-time disaster data from Twitter to predict the path a disaster like a tornado will take. The users of Twitter act as the sensors which provide useful information about the disaster by posting first-hand experience, warnings or location of a disaster. The steps involved in the framework are – data collection, data preprocessing, geo-locating the tweets, data filtering and extrapolation of the disaster curve for prediction of susceptible locations. The framework is validated by analyzing the past events. This framework has the potential to be developed into a full-fledged system to predict and warn people about disasters. The warnings can be sent to news channels or broadcasted for pro-active action.

Background: Dengue is a viral infectious disease that is transmitted by mosquitoes. The disease causes a significant health burden in tropical countries, and has been a public health burden in Singapore for several decades. Severe complications such as hemorrhage can develop and lead to fatal outcomes. Before tetravalent vaccine and drugs are available, vector control is the key component to control dengue transmission. Vector control activities need to be guided by surveillance of outbreak and implement timely action to suppress dengue transmission and limit the risk of further spread. This study aims to explore the feasibility of developing a dengue early warning system using temperature and rainfall as main predictors. The objectives were to 1) analyze the relationship between dengue cases and weather predictors, 2) identify the optimal lead time required for a dengue early warning, 3) develop forecasting models, and 4) translate forecasts to dengue risk indices. Methods: Poisson multivariate regression models were established to analyze relative risks of dengue corresponding to each unit change of weekly mean temperature and cumulative rainfall at lag of 1-20 weeks. Duration of vector control for localized outbreaks was analyzed to identify the time required by local authority to respond to an early warning. Then, dengue forecasting models were developed using Poisson multivariate regression. Autoregression, trend, and seasonality were considered in the models to account for risk factors other than temperature and rainfall. Model selection and validation were performed using various statistical methods. Forecast precision was analyzed using cross-validation, Receiver Operating Characteristics curve, and root mean square errors. Finally, forecasts were translated into stratified dengue risk indices in time series formats. Results: Findings showed weekly mean temperature and cumulative rainfall preceded higher relative risk of dengue by 9-16 weeks and that a forecast with at least 3 months would provide sufficient time for mitigation in Singapore. Results showed possibility of predicting dengue cases 1-16 weeks using temperature and rainfall; whereas, consideration of autoregression and trend further enhance forecast precision. Sensitivity analysis showed the forecasting models could detect outbreak and non-outbreak at above 90% with less than 20% false positive. Forecasts were translated into stratified dengue risk indices using color codes and indices ranging from 1-10 in calendar or time sequence formats. Simplified risk indices interpreted forecast according to annual alert and outbreak thresholds; thus, provided uniform interpretation. Significance: A prediction model was developed that forecasted a prognosis of dengue up to 16 weeks in advance with sufficient accuracy. Such a prognosis can be used as an early warning to enhance evidence-based decision making and effective use of public health resources as well as improved effectiveness of dengue surveillance and control. Simple and clear dengue risk indices improve communications to stakeholders.

Thesis (Ph. D.)--University of California, San Diego, 1999. / Vita. Includes bibliographical references (leaves 350-356).

The aim of this study is to investigate if individuals reacts rational to the announcement of negative profit warnings in the Swedish stock market. This is done by using an event study approach, investigating the corresponding abnormal returns and cumulative abnormal returns before, during, and after the announcement. Tests is also made to see whether qualitative and quantitative profit warnings and firm size has any impact on the cumulative abnormal returns. The sample consists of 176 profit warnings from 2008 to 2018. On the announcement day, the average abnormal return at day zero was -6.99 % and the average cumulative abnormal returns at day zero and one was -9.06 %. The results found also that smaller firms generate lower abnormal returns on the announcement date, but that there is no difference between qualitative and quantitative profit warnings. With small and insignificant cumulative abnormal returns before and after the announcement, the reached conclusion is that the market is efficient on aggregate level during the event of negative profit warnings.

Growing natural disasters, catastrophes, indrustry accidents, mass disasters and dangter of usingt modern technologies are reason for serious crisis situations when huge damages arise and there are also human victims in these affected areas. Above all local authorities and integrated rescue system give the first aid to the poeople there. Logistical operations are used to mitigate the impact of this crisis situations too. Also the thesis has got a purpose to find out and evaluate the security of population´s protection in communities with extended activity Tábor, Soběslav and Jindřichův Hradec, to find out their readiness and in this way to confirm or refute the research question. It was determined as follows: Is logistic and its acivities determined to secure the people in chosen communities with extended activity sufficient to manage crisis situations and emergencies? Nowadays huge attention is paid to population´s security. In the theoretical part of the thesis the necessary terminology is defined which goes through the whole work. Individual chapters are dedicated to the description of local government units and solutions of emergencies. In other capters the security of population is described there are legislation of warning, hiding, evacuation, emergency survival and demarcation of integrated rescue system. Logistical problems are described, its historical progress and in particular chapters there are logistical goals, logistical activities, logistic and population´s security.There is also defined a role of State fuel reserves, units of the volunteer firefihters and non governmental non profit organisations. Methodics of this thesis consisted in assemby of literary sources regarding given issues. Then legislation in force of the Czech republic was used. By processing the internet sources were used too above all to access to legislation in force in full and then oficiall websites of Home office of the Czhech Republic, State fuel reserves, Central government authorities which deal with given issues. Qualitative research where technical, material and financial security was regarded in chosen areas was used in this thesis. Structured interview with emergency managment personnel of communities with extended acivities were used for obtaining data where activities implemented within the municipality werwe observed not in terriorial scope of the commuinity with extended activity. For finding the state of readiness if the activities aimed at protection population in chosen communities are sufficient the comprehensive index of readiness was chosen. Subsequently analysis and comprasison of the issues were made. Based on the evaluation the recommendation for improvement of readiness of the chosen communities were suggested at the and of the thesis. Then own conclusion of the thesis inform about fulfillment of the stated objectives and based on results said in this thesis about positive answer to given search question.