<p>The transportation cost of logs from forest to customers is a large part of the overall cost for the Swedish forestry industry. Finding good routes from harvesting points to saw and pulp mills is a complex task, where the total number of feasible routes is extremely high. In this thesis we present two methods for log truck scheduling. </p><p>The first is to, from a given set of routes, find the most valuable subset that fulfils the customers demand. We use a model that is similar to the set partitioning problem and a method that is referred to as a composite pricing coupled with Branch and Bound. The composite pricing based method prices the routes (columns) and chooses the most valuable ones that are then added to the LP relaxation. Once an LP optimum is found, the Branch and Bound method is used to find an integer optimum solution. We have tested this on a case of realistic size. </p><p>The second method is a tabu search heuristic. Here, the purpose is to create efficient and qualitative routes from a given number of trips (referred to as predefined trips). From a start solution tabu search systematically generates new solutions. This method was tested on a small problem and on a five times larger problem to study how the size of the problem affected the result. It was also tested and compared on two cases in which the backhauling possibilities (i.e. instead of traveling empty the truck picks up another load on the return trip) had and had not been studied. The composite pricing based method and the tabu search method proved to be very useful for this kind of scheduling.</p>

<p>Traffic planning in a modern congested society is an important and time consuming procedure. Finding fast algorithms for solving traffic problems is therefore of great interest for traffic planners allover the world. </p><p>This thesis concerns solving the fixed demand traffic assignment problem (TAP) on a number of different transportation test networks. TAP is solved using the Frank-Wolfe algorithm and the shortest path problems that arise as subproblems to the Frank-Wolfe algorithm are solved using the network simplex algorithm. We evaluate how a number of existing pricing strategies to the network simplex algorithm performs with TAP. We also construct a new efficient pricing strategy, the Bucket Pricing Strategy, inspired by the heap implementation of Dijkstra's method for shortest path problems. This pricing strategy is, together with the actual use of the network simplex algorithm, the main result of the thesis and the pricing strategy is designed to take advantage of the special structure of TAP. In addition to performing tests on the conventional Frank-Wolfe algorithm, we also test how the different pricing strategies perform on Frank-Wolfe algorithms using conjugate and bi-conjugate search directions. </p><p>These test results show that the updating shortest path calculations obtained by using the network simplex outperforms the non-updating Frank-Wolfe algorithms. Comparisons with Bar-Gera's OBA show that our implementation, especially together with the bucket pricing strategy, also outperforms this algorithm for relative gaps down to 10E-6.</p>

Analytical interpolation theory has several applications in systems and control. In particular, solutions of low degree, or more generally of low complexity, are of special interest since they allow for synthesis of simpler systems. The study of degree constrained analytic interpolation was initialized in the early 80's and during the past decade it has had significant progress. This thesis contributes in three different aspects to complexity constrained analytic interpolation: theory, numerical algorithms, and design paradigms. The contributions are closely related; shortcomings of previous design paradigms motivate development of the theory, which in turn calls for new robust and efficient numerical algorithms. Mainly two theoretical developments are studied in the thesis. Firstly, the spectral Kullback-Leibler approximation formulation is merged with simultaneous cepstral and covariance interpolation. For this formulation, both uniqueness of the solution, as well as smoothness with respect to data, is proven. Secondly, the theory is generalized to matrix-valued interpolation, but then only allowing for covariance-type interpolation conditions. Again, uniqueness and smoothness with respect to data is proven. Three algorithms are presented. Firstly, a refinement of a previous algorithm allowing for multiple as well as matrix-valued interpolation in an optimization framework is presented. Secondly, an algorithm capable of solving the boundary case, that is, with spectral zeros on the unit circle, is given. This also yields an inherent numerical robustness. Thirdly, a new algorithm treating the problem with both cepstral and covariance conditions is presented. Two design paradigms have sprung out of the complexity constrained analytical interpolation theory. Firstly, in robust control it enables low degree Hinf controller design. This is illustrated by a low degree controller design for a benchmark problem in MIMO sensitivity shaping. Also, a user support for the tuning of controllers within the design paradigm for the SISO case is presented. Secondly, in ARMA estimation it provides unique model estimates, which depend smoothly on the data as well as enables frequency weighting. For AR estimation, a covariance extension approach to frequency weighting is discussed, and an example is given as an illustration. For ARMA estimation, simultaneous cepstral and covariance matching is generalized to include prefiltering. An example indicates that this might yield asymptotically efficient estimates. / QC 20100928

The transportation cost of logs from forest to customers is a large part of the overall cost for the Swedish forestry industry. Finding good routes from harvesting points to saw and pulp mills is a complex task, where the total number of feasible routes is extremely high. In this thesis we present two methods for log truck scheduling. The first is to, from a given set of routes, find the most valuable subset that fulfils the customers demand. We use a model that is similar to the set partitioning problem and a method that is referred to as a composite pricing coupled with Branch and Bound. The composite pricing based method prices the routes (columns) and chooses the most valuable ones that are then added to the LP relaxation. Once an LP optimum is found, the Branch and Bound method is used to find an integer optimum solution. We have tested this on a case of realistic size. The second method is a tabu search heuristic. Here, the purpose is to create efficient and qualitative routes from a given number of trips (referred to as predefined trips). From a start solution tabu search systematically generates new solutions. This method was tested on a small problem and on a five times larger problem to study how the size of the problem affected the result. It was also tested and compared on two cases in which the backhauling possibilities (i.e. instead of traveling empty the truck picks up another load on the return trip) had and had not been studied. The composite pricing based method and the tabu search method proved to be very useful for this kind of scheduling.

Traffic planning in a modern congested society is an important and time consuming procedure. Finding fast algorithms for solving traffic problems is therefore of great interest for traffic planners allover the world. This thesis concerns solving the fixed demand traffic assignment problem (TAP) on a number of different transportation test networks. TAP is solved using the Frank-Wolfe algorithm and the shortest path problems that arise as subproblems to the Frank-Wolfe algorithm are solved using the network simplex algorithm. We evaluate how a number of existing pricing strategies to the network simplex algorithm performs with TAP. We also construct a new efficient pricing strategy, the Bucket Pricing Strategy, inspired by the heap implementation of Dijkstra's method for shortest path problems. This pricing strategy is, together with the actual use of the network simplex algorithm, the main result of the thesis and the pricing strategy is designed to take advantage of the special structure of TAP. In addition to performing tests on the conventional Frank-Wolfe algorithm, we also test how the different pricing strategies perform on Frank-Wolfe algorithms using conjugate and bi-conjugate search directions. These test results show that the updating shortest path calculations obtained by using the network simplex outperforms the non-updating Frank-Wolfe algorithms. Comparisons with Bar-Gera's OBA show that our implementation, especially together with the bucket pricing strategy, also outperforms this algorithm for relative gaps down to 10E-6.

The purpose of this study was to explore unaccompanied refugee children / young people’s experiences of support from social services in the near term after the decision on permanent residence. Previous research has focused mainly on other aspects of integration. The theoretical approach was based on systems theory and Antonovsky’s theory of SOC (sense of coherence). Four young people were interviewed. The design was qualitative with an inductive approach. The results of the interviews were divided into four themes: experienced support, expected support, participation and required support. A recurring theme in the interviews was that respondents had difficulty understanding the social services role and thus know what support they could expect. They also expressed a need for greater participation in the context of social services different decisions. / Syftet med denna studie var att utforska ensamkommande flyktingbarns/ungdomars upplevelse av stöd från socialtjänsten under den närmaste tiden efter beslut om permanent uppehållstillstånd. Tidigare forskning har framför allt studerat andra aspekter av integrationen. Den teoretiska ansatsen utgick från systemteori samt Antonovskys teori om KASAM (känsla av sammanhang). Fyra ungdomar djupintervjuades. Designen var kvalitativ med en induktiv ansats. Resultaten av intervjuerna indelades i fyra teman: upplevt stöd, förväntat stöd, delaktighet och önskat stöd. Ett genomgående tema i intervjuerna var att respondenterna hade svårt att förstå socialtjänstens roll och därmed veta vilket stöd de kunde förvänta sig. De uttryckte också ett behov av större delaktighet i samband med socialtjänstens olika beslut.

In present study interviews with five officials and the gathering of documentation carried out in a reception center for newly arrived refugees located in a medium-sized municipality in central Sweden. The aim has been on the basis of the collected empirical data to evaluate how the municipality worked to promote the integration of newcomers, what measures were available, whether there were existing goals, and how they were formulated, and the extent to which they were implemented. This constituted, together with earlier research and systems theory based framework for the study's conclusions. The study showed that communication between and within the investigated unit was partly flawed. It has also showed that there was a degree of conflict in organizational approaches within the examined entity which could cause bottlenecks in the activity. The current study also showed the difficulty in estimating the resources currently needed to cover the need of, among others, Swedish for immigrants. / I föreliggande studie har intervjuer av fem tjänstemän samt insamlande av styrdokument genomförts i en mottagningsenhet för nyanlända flyktingar beläget i en medelstor kommun i Mellansverige. Syftet har utifrån insamlad empiri varit att utvärdera hur kommunen arbetat för att främja integrationen av de nyanlända, vilka insatser som stod till buds, huruvida det existerat uppsatta mål, samt hur dessa var formulerade och i vilken utsträckning de efterlevts. Detta utgjorde tillsammans med den utvalda forskningen och den systemteoretiska basen ramverket för studiens slutsatser vilka resultat- och analysdelen grundat sig på. Studien visade att kommunikationen mellan och inom undersökt verksamhet till viss del var bristfällig. Den har även påvisat att det förekom ett visst mått av stridande organisatoriskt synsätt inom den undersökta enheten vilket kunde orsaka flaskhalsar i verksamheten. Den genomförda studien visade även på svårigheten i att beräkna vilka resurser som för tillfället behövdes för att täcka behovet av bland annat SFI-platser.

Föreliggande studie har genom kvalitativ forskning med utgång i systemteorin syftat till att kartlägga den enskilda missbrukarens väg till missbruksbehandling. Tre semistrukturerade intervjuer har genomförts och sedermera analyserats. Missbrukare utgör en särskild kategori i socialtjänstlagen. Därtill står det att finna i lagrum 3 kap 1 § (SFS 2001:453) att socialtjänsten genom uppsökande verksamhet ska göra sig väl förtrogen med levnadsförhållandena i kommunen. Därtill även informera om socialtjänsten i kommunen och genom uppsökande verksamhet och på annat sätt främja förutsättningarna för goda levnadsförhållanden. Resultat har påvisat att det i första hand är missbrukarens anhöriga som stöttar dem till kontaktsökande vad gällande behandling. Studien har därtill även påvisat att missbrukaren i första hand inte vänt sig till socialtjänsten utan sökt sig till andra instanser. Respondenterna i studien har samtliga haft enskilda agendor vad gällande uppnådd drogfrihet. Vad som dock förefallit signifikant bland deltagarna har varit en strävan om bättre relationer med sin familj. Ytterligare en av studiens slutsatser är att socialtjänsten bör utöka sin informationsspridning till kommuninvånare om att missbruksbehandling finns att tillgå och hur hjälpen är utformad. / The present study has the qualitative research with the output of systems theory aimed to identify the individual abuser path to addiction treatment. Three semi-structured interviews have been conducted and subsequently analyzed. Addicts constitute a special category in the Social Services Act. In addition, it is to be found in the section of the law Chapter 3, 1 § (SFS 2001: 453) that the social outreach should make themselves familiar with the living conditions in the municipality. In addition, also provide information on social services in the municipality and through outreach activities and other means to promote conditions for good living conditions. Results have demonstrated that it is primarily the abuser's family members who support them to contact applicants as current treatment. The study has also revealed that although the addict in the first place not turned to social services, but turned to other instances. Respondents in the study all had individual agendas as applicable achieved abstinence. What, however, seemed significant among the participants has been a quest for better relationships with their family. Another of the study's conclusions is that social services should expand its dissemination of information to local residents about drug treatment are available and how the aid is designed.

<p>Syftet med studien var att undersöka vad som får män som brukar våld mot sin kvinnliga partner att motivera sig att få professionell hjälp, samt att påbörja och fortsätta ett förändringsarbete. De frågeställningar som använts handlade om hur männen hittar motivation, vad som gör att de vill förändras, vad i den professionella relationen de tycker är positivt respektive negativt för förändring samt vad i deras övriga tillvaro som hindrar eller främjar förändring. För detta användes en kvalitativ metod som bestod av halvstrukturerade intervjuer med tre män som gick i ett behandlingsprogram via frivården efter att ha utövat våld i nära relation. Det insamlade materialet strukturerades upp i teman som var centrala i männens berättelser och som kunde kopplas till syftet. Resultatet analyserades med hjälp av ett ekologiskt systemteoriperspektiv samt begrepp från generell systemteori och socialpsykologi. Vidare jämfördes männens utsagor med resultat av tidigare forskning på området. Det visade att männen främst såg sin partner och barn som skäl att förändras. Det visar också att olika situationer som de upplevde som krisartade gjorde att de hittade motivation att acceptera hjälp. Vidare att ansvarstagande för sina handlingar, kommunikation och empati har stor påverkan på att hitta motivation och att förändras för de tre männen.</p>

The purpose of this study was to investigate how the social services and the police co-operate with each other when they come into contact with an individual within their realms of influence. It has been shown in a report by Fridolf (2008) that co-operation is not the aim itself but used as a mean to reach for better processes and better results. We have used qualitative interviews in the study, where three social workers and three policemen have participated from the same municipality to answer our questions. To analyze our result we have used system theory and organization theory. The result of our study shows that within this specific municipality the two agencies co-operate very well. The main reasons why are that co-operation has been going on for a long time and that because of this they have been able to build up a good strategy that works well. Another reason is the fact that this very municipality is relatively small, which in its turn leads to closeness to each other which makes it easy to get in contact and to be aware of who the others involved are. However, this very co-operation can sometimes cause friction, because of the fact that the police and the social services do not always get the same picture of the youth that they are working with. This is because both agencies get to see the youth in different circumstances. The police see the youth from the perspective of being a perpetrator and the social services see the youth from the perspective of needing help. This is something that from both sides can be looked upon as being unfavorable in certain circumstances which could also in other words cause a friction in the co-operation. / Syftet med denna uppsats var att undersöka hur organisationerna socialtjänsten och polisen samarbetar. Det har visat sig, precis som Fridolf (2001) påstår i sin rapport, att samarbete inte är målet i sig utan en resurs för att skapa en bättre process och ett bättre resultat. Vi använde oss av kvalitativ metod för att utföra vår studie. Vi utförde därmed kvalitativa intervjuer där tre socialtjänstarbetare och tre poliser har deltagit från samma kommun för att svara på våra frågor. För att analysera vårt resultat har vi använt oss av systemteori och organisationsteori. Fungerar inte arbetet mellan de båda organisationerna kan detta bli förödande för individen. Resultatet av vår studie visar att inom denna specifika kommun fungerar samarbetet mycket bra. De skäl som nämns är att samarbetet har pågått under en lång tid och att man därför har lyckats bygga upp en god strategi som fungerar väl. Andra skäl som nämns är att just denna kommun är förhållandevis liten, vilket i sin tur leder till att närheten till varandra gör att man lätt kan få kontakt och att man vet vilka alla de som är involverade är. Det som kan ses som negativt i samarbetet och som ibland kan skapa friktion mellan dem, är det faktum att polisen och socialtjänsten inte alltid får samma bild av ungdomen de arbetar gemensamt med. Detta eftersom de båda aktörerna oftast får se ungdomen i olika sammanhang. Polisen ser ungdomen från perspektivet förövare och socialtjänst ser ungdomen från perspektivet hjälpbehövande. I och med detta bemöter de olika aktörerna ungdomen på olika sätt. Detta är något som från båda håll kan ses som ofördelaktigt i vissa tillfällen vilket med andra ord kan skapa friktion i samarbetet.