Methods for allocating redundant controls for systems with four or more objectives are studied. Previous research into aircraft control allocation has focused on allocating control effectors to provide commands for three rotational degrees of freedom. Redundant control systems have the capability to allocate commands for a larger number of objectives. For aircraft, direct force commands can be applied in addition to moment commands. When controls are limited, constraints must be placed on the objectives which can be achieved. Methods for meeting commands in the entire set of of achievable objectives have been developed. The Bisecting Edge Search Algorithm has been presented as a computationally efficient method for allocating controls in the three objective problem. Linear programming techniques are also frequently presented. This research focuses on an effort to extend the Bisecting Edge Search Algorithm to handle higher numbers of objectives. A recursive algorithm for allocating controls for four or more objectives is proposed. The recursive algorithm is designed to be similar to the three objective allocator and to require computational effort which scales linearly with the controls. The control allocation problem can be formulated as a linear program. Some background on linear programming is presented. Methods based on five formulations are presented. The recursive allocator and linear programming solutions are implemented. Numerical results illustrate how the average and worst case performance scales with the problem size. The recursive allocator is found to scale linearly with the number of controls. As the number of objectives increases, the computational time grows much faster. The linear programming solutions are also seen to scale linearly in the controls for problems with many more controls than objectives. In online applications, computational resources are limited. Even if an allocator performs well in the average case, there still may not be sufficient time to find the worst case solution. If the optimal solution cannot be guaranteed within the available time, some method for early termination should be provided. Estimation of solutions from current information in the allocators is discussed. For the recursive implementation, this estimation is seen to provide nearly optimal performance. / Ph. D.

Attacks on the heap are an increasingly severe threat. State-of-the-art secure dynamic memory allocators can offer protection, however their memory consumption is high, making them suboptimal in many situations. We introduce sys, a secure allocator whose design is driven by memory efficiency. Among other features, sys uses an efficient fine-grain size classes indexing mechanism and implements a novel dynamic canary scheme. It offers a low memory overhead due its size classes optimized for canary usage, its on-demand metadata allocation, and the combination of randomized allocations and over-provisioning into a single memory efficient security feature. sys protects against widespread heap-related attacks such as overflows, over-reads, double/invalid free, and use-after-free. Evaluation over a wide range of applications shows that it offers a significant reduction in memory consumption compared to the state-of-the-art secure allocator (up to 2x in macro-benchmarks), while offering similar or better security guarantees and good performance. / Master of Science / Attacks targeting on the runtime memory (heap allocator) are severe threats to software safety. Statistical results shown that the numbers of heap-related attacks has doubled since 2016. A large number of research works are designed to solve the security problems by offering different techniques to prevent some specific attacks. Not only are they very secure but also fast. However, these secure heap allocators sacrifice the memory usage, all of them at least double the memory consumption. Our work is trying to design and implement a heap allocator, in which it can defend against different attacks, as well as fast and memory-efficient. We carefully re-design some security features in our heap allocator while keep memory-efficient in mind. In the end, we evaluated sys and found that it offers significant reduction on different benchmarks suites. Evaluation also showed that sys can detect a lot of vulnerabilities in the software, while offer the same good performance as the state-of-the-art heap allocator.

L'optimisation de l'utilisation des liens satellites est un enjeu majeur pour augmenter la rentabilité des systèmes satellites. L'augmentation de la réutilisation des fréquences est une des approches les plus prometteuses. La réutilisation des fréquences permet de transmettre plus d'informations sur une même fréquence, pour peu que les interférences entre les deux signaux ne soient pas trop importantes. Il est donc capital de contrôler l'impact de ces interférences, que ce soit via l'utilisation de schémas de réutilisation de fréquences, ou encore via des techniques de coordination dynamique des interférences, où la sélection des utilisateurs qui peuvent transmettre sur les mêmes fréquences est faite en prenant les interférences en compte / Optimizing satellite links is a major challenge to increase satellite systems profitability. Increasing the frequency reuse is one of the most promising approaches. Reusing multiple times the same frequency enables to transmit more information on the same frequency, as long as the two or more signals do not generate too high mutual interferences. It is therefore of capital importance to control these interference impacts, be it through the use of frequency reuse scheme or through the use of advanced dynamic interference coordination techniques, where the user selection is done with the knowledge of interference levels.

Insurance companies offer business and individuals the possibility to reduce the financial impact of a risk occurring by transferring it away from themselves onto someone. For taking on risk on behalf of someone else the insurance company requires a premium from the policyholder which is pooled and invested in order to meet future obligations towards the policyholder. However, the importance of the European insurance industry goes beyond economic protection of the policyholder as the industry with its EUR8.4 trillion or 58 percent of EU GDP in assets is the largest institutional investor in Europe. As the financial system has undergone dramatic transformation over time, so have the role and function of intermediaries changed. While traditional tasks like reducing transaction costs and asymmetric information became less relevant, facilitating of risk transfer and dealing with the increasing breadth and depth of financial markets are gaining more and more importance. While insurers have been able to hold illiquid asset to a larger extent arguments from the industry are made that the planned introduction of Solvency II will limit insurers and overlook their investment abilities, which is something that can affect the region’s economic development. The above mention aspect combined with the limited research that has been conducted on insurers’ asset allocation and the performance of it resulted in the following research question: Does asset allocation impact insurance company's performance? The question focuses on insurers within the European Union (EU) which is enlarged by the European Economic Area (EEA) and Switzerland, where performance is measured as the return on investment (ROI). To answer the research question in the best possible way, relevant theories such as Modern Portfolio Theory or Efficient Market Hypothesis are presented and discussed as well as previous research on asset allocation. Earlier studies about asset allocation policy and its power to explain the investment return came to different conclusions which can be due to variation in the interpretation of the findings or difficulties by distinguishing between asset allocation policy and active asset allocation. Census is used to investigate in the topic as the population of listed insurance companies within the selected region was rather small which finally came down to 42 firms due to the timeframe of 11 years. Data regarding insurer’s asset class weights in debt securities, equity, real estate, derivatives, cash and equivalent, loans and receivables and the category of others were collected. The return on investment was also collected for each year of the time period and for each insurance company. Benchmarks were constructed in order to replicate what the return of a passive investment of the same proportion would have yielded. The result was inconclusive as it was not possible to determine if asset allocation policy or active management have the greatest impact on the return on investment. This is contradicting previous research of asset allocation and performance as researchers have found that asset allocation policy explains most or all of the return.

Thesis (Ph. D., Natural Resources)--University of Idaho, May 2007. / Major professor: Jo Ellen Force. Includes bibliographical references (leaves ). Also available online (PDF file) by subscription or by purchasing the individual file.

This thesis aims to propose a multi-agent based hierarchical model for the operations of container terminals. We have divided our model into four key agents that are involved in each sub processes. The proposed agent allocation policies are recommended for different situations that may occur at a container terminal. A software prototype is developed which implements the hierarchical model. This web based application is used in order to simulate the various processes involved in the following operations on the marine side in a case study of a container terminal in Sweden by adopting a multi-agent based simulation technique. Due to the increase in usage of container transportation, container terminals are experiencing difficulties in the management of the operations. The software provides a decision support capability to terminal managers for scheduling and managing the operations effectively while also visually presenting the time it takes to complete the process and its associated cost. Terminal managers need to implement certain policies to improve the management and operations of the container terminal. The policies are evaluated and tested under various cases to provide a more comparative overview. The results of the simulation experiments indicate that the waiting time for arriving vessels is decreasing when in queue with more than three vessels arriving on same day. / Simulation is a good technique that help analyst to take decision considering each factor of problem that is to be simulated. Simulation in addition with multi agent environment provides better understanding of modeling the entities. The complexity of CT environment and multiple involvement of agents simultaneously enables CT suitable domain for multi agents. We have modeled the four CT operations that are carried out at each CT. These operations are modeled in hierarchical sequence like berth allocation, QCs allocation, Transport vehicles allocation and YCs allocation. The most important factor of simulation is the measurement of dynamic time of each operation. We have simulated and compared different agents active time and service time compared with associated cost. The berth allocation is very important asset from all the operations that are carried out at the CTs. The effective utilization of FCFS berth allocation policy reduces the vessel waiting time in waiting queue. The developed terminal simulator tool allocates all resources dynamically while looking at the number of containers that will be loaded and unloaded at QS and yard storage area. The result of simulation tool presents the good dynamic allocation of transport vehicles. The dynamic resource allocation helps to minimize the congestion and bottlenecks that may occur at CTs. The result of three experiments depicts that the berth allocation and agent allocation is improved and vessel service time is reduced at berth side which automatically reduces vessels waiting time in queue. Besides this the transport allocation and YCs allocation is dynamically assigned by looking at number of containers in the vessels. The terminal simulator helps managers to analyze the simulated results and take better decision at hand.

This thesis is theresult of a project aimed at developing a tool for allocation of risk capitalin catastrophe excess-of-loss reinsurance. Allocation of risk capital is animportant tool for measuring portfolio performance and optimizing the capitalrequirement. Here, two allocation rules are described and analyzed, Eulerallocation and Capital layer allocation. The rules are applied to two differentportfolios. The main conclusions is that the two methods can be used togetherto get a better picture of how the dependence structure between the contractsaffect the portfolio result. It is also illustrated how the RORAC of one of theportfolios can be increased by 1 % using the outcome from the analyses. / Den här uppsatsen är resultatet av ett projekt som syftat till att utveckla en mjukvara för allokering av riskkapital inom icke-proportionell katastrofåterförsäkring. Allokering av riskkapital är ett viktigt verktyg för att mäta hur väl portföljen presterar samt en grund för portföljoptimering. I den här uppsatsen undersöks två metoder för att allokera riskkapital, Euler-allokering och Capital layer allokering. Metoderna appliceras på två olika portföljer. Slutsatserna är att de två metoderna kan användas tillsammans för att ge en helhetsbild av beroendet mellan kontrakten centralt i fördelningsfunktionen samt ute i svansen. Det visas också hur portföljens RORAC kan höjas med 1 % genom att använda resultaten i uppsatsen.

M. Ing. / The report presents and analyses allocation methods for assigning limited resources to project tasks. The report is partitioned into five chapters beginning with an introductory chapter. Chapter 1 summarises the problem and describes the process followed in addressing the problem. A literature chapter covers the literature for the development and analysis of the methods presented in the report. Chapter three presents the allocation methods and discusses the role of the methods in single and multi-project resource allocation. Two commercial methods (Hu’s Algorithm; and Coffman’s and Munt’s Algorithm) along with a recipe for implementation are discussed. It is followed by the introduction and formulation of two additional methods that base their resource allocation on critical and least slack chains (Least Slack and Least Slack Ancestors First methods). A final method, based on locating the best possible solution, is presented and formulated (Best Fit method). A case study is presented in chapter four which is applied to each of the formulated methods in chapter three. Key metrics are derived and necessary compassions among the methods are performed. Chapter 4 concludes with an analysis of the comparisons. Finally Chapter five presents a conclusion to the report summarising the results of chapters three and four. Future recommendations are also discussed with the main emphasis on a possible investigation of a hybrid method stemming from the application and analysis in chapter four.

Titel Rättvisa priser – En fallstudie på Volvo Construction Equipment (CE)Nyckelord Kostnadsfördelning, produktkalkylering, rättvis kostnadsfördelning, aktivitetsfördelning,värdeskapande aktiviteter.Syfte Syftet med fallstudien är att kartlägga värdeskapande aktiviteter, undersökavilken aktivitet som differentierar produkterna bäst och se hurprocesstiden/tiderna för en aktivitet kan användas som fördelningsnyckel vidfördelning av kostnader.Målningsprocessens aktiviteter har grundligt granskats och av dessa har de värdeskapandeprocesserna identifierats. Två slutsatser har dragits av fallstudien: Den tid som differentierar produkterna bäst är mantiden. Desto fler aktiviteter som involveras i kostnadsfördelningen, desto rättvisare blirkostnadsfördelningen. En summering av tiden i målningsroboten, rengöringen ochmantiden resulterar i ett bra underlag att kostnadsfördela på. Med reservation för attarbetet som utförs av operatörerna, mantiden, helst ska vara standardiserat.Produktkalkylering handlar om att fördela ett företags kostnader på dess produkter, vilket ärlättare sagt än gjort. Problemet kring kostnadsfördelning har diskuterats fram och tillbaka desenaste femtio åren. Hur ska ett företag fördela sina kostnader, direkta och indirekta, på sinaprodukter och tjänster för att de ska generera ett rättvist pris för produkterna och tjänsterna? Dedirekta kostnaderna är enkla att härleda till sitt kostnadsobjekt, men de indirekta kostnaderna ärbetydligt besvärligare.Studien undersöker vilka processer som är värdeskapande i målningsprocessen och av dessaprocesser har fyra olika scenarier skapats. Varje scenario består av olika värdeskapandeaktiviteter och deras processtider. Finansavdelningen på Volvo CE simulerade enkostnadsfördelning med varje scenario som underlag för fördelningen och utfallet avsimuleringen analyserades.Studien är gjord som en fallstudie på måleriavdelningen på Volvo CE. Författarna är EmiliaVardanyan och Erik Söder. Handledare på högskolan är universitetslektor Antti Salonen ochhandledare på Volvo CE produktionschef Josef Lännerstöm. / Title Fair prices – A case study in Volvo Construction Equipment (CE)Keywords Cost allocation, product costing, fair cost allocation, activity allocation, valueaddedactivities.Purpose The purpose of this paper is to locate the value added activities, investigatewhich activity that differentiate the products best and see how the processtime/times for an activity can be used as an allocation key for allocating costs.The activities at the department of painting have been examined and the value-added activitiesof these have been identified. Two conclusions have been made by the work. The time that differentiate the products best are the manual time, the work performedby man. The more activities that the cost allocation includes the more correct and fair thecalculation will be. The sum of the time in the painting robot, the cleaning process andthe manual time result in good a basis for cost allocation. With the reservation that thework performed by man should be standardized.Product calculation is about allocation of the cost in a company, which is easier said than done.The problems related to cost allocation has been discussed back and forward the latest fiftyyears. How should companies allocate their costs, direct and indirect costs, on their productsand services to give their products and services a fair price? The direct costs are easy to deriveto their cost object, but the indirect costs are way harder to work with.This paper investigates which processes that are value-adding in the paint shop and from theseprocesses four scenarios are made. Every scenario is made of different value-added activitiesand their process times. The finance department at Volvo CE simulated a cost allocation withevery scenario as basis and the result of the simulation were analysed.The work has been done as a case study in the paint shop at Volvo CE. The authors are EmiliaVardanyan and Erik Söder. The supervisor at Mälardalens university are associated professorAntti Salonen and the supervisor at Volvo CE are manager production engineering assemblyJosef Lännerström.

This thesis concerns communication across channels with multiple inputs and multiple outputs. Specifically, we consider the closed-loop scenario in which knowledge of the state of the multiple-input multiple-output (MIMO) channel is available at the transmitter. We show how this knowledge can be exploited to optimize performance, as measured by the zero-outage capacity, which is the capacity corresponding to zero outage probability. On at-fading channels, a closed-loop transmitter allocates different powers and rates to the multiple channel inputs so as to maximize zero-outage capacity. Frequency-selective fading channels call for a combination of orthogonal-frequency-division multiplexing (OFDM) and MIMO known as MIMO-OFDM. This exacerbates the allocation problem because it multiplies the number of allocation dimensions by the number of OFDM tones. Fortunately, this thesis demonstrates that simple allocations are sufficient to approach the zero-outage capacity. These simple strategies exploit the tendency for random MIMO channels to behave deterministically as the number of inputs becomes large.