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(2019)Syftet med avhandlingen är att undersöka öppna reparationsinitiativ i svenska samtal vid biljettluckor i Finland och Sverige och svara på frågorna vilka initiativen är, varför de produceras samt vilken respons de får. Avhandlingen identifierar de svenska öppna initiativen och undersöker deras funktioner och användning, pekar ut möjliga problemkällor i den fysiska och sekventiella omgivningen samt redogör för olika reparationshandlingar och hur de språkligt formuleras. Begreppet reparation utgör en grundläggande term i avhandlingen och presenteras utgående från samtalsanalytiska teorier. Samtalsanalysen som metod tillämpas i stora delar av analysen men kombineras med teorier och begrepp specifika för institutionella samtal och kundsamtal för att närmare kunna förstå reparationssekvenserna i den kontext de verkar i. Avhandlingen ser servicemötet som en kommunikativ verksamhetstyp som är bunden till rättigheter och skyldigheter samt förväntningar förknippade med dessa och samtalets förlopp. Materialet består av samtal vid biljettkassor som spelats in för forskningsprojektet Interaktion och variation i pluricentriska språk (IVIP). Biljettkassorna i Finland finns i Helsingfors, Vasa samt Jakobstad och biljettkassorna i Sverige i Stockholm och Göteborg. Materialet utgör 369 samtal på 16 timmar och 10 minuter. Avhandlingen visar att de vanligaste öppna initiativen i svenskan är va sa du, va och förlåt eller ursäkta. Va sa du används oftast till skillnad från finskan och engelskan där kortare initiativformer är vanligare. Det förekommer inget samband mellan problemkällorna och reparationerna som initieras, men då kunden signalerat interaktionell otillgänglighet reparerar hen med antingen förlåt/ursäkta eller va sa du. Problemkällor i den fysiska omgivningen är biljettkassans utformning, placering samt bakgrundsljud. Mikrofon och högtalare som artefakter utgör en viktig del av personalens arbete för att hantera reparationer och nå samförstånd. Problemkällor i den sekventiella omgivningen är överlappande tal, oväntade vändningar och ändringar i deltagarramen. Reparationshandlingarna utgörs av identiska upprepningar, modifierade upprepningar samt omformuleringar. De modifierade upprepningarna visar att det finns segment som samtalsdeltagarna ser som ”överflödiga” i den responderande turen, bl.a. företal samt TKE-initiala markörer och led. Talarna kan också lägga till förtydligande led. Mindre modifieringar är förtydligande eller tillägg av ord och/eller partikel och ändring av verbets aktionsart. I de responderande turerna tillämpas även prosodiska (högre volym, långsammare tal m.m.) och språkliga (splittring av turen) strategier.
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(2011)Tutkimus on kvalitatiivinen tapaustutkimus. Tutkimuksen tarkoitus on selvittää mitkä ovat OP -Pohjola-ryhmän tärkeimmät sidosryhmät, millä perusteella sidosryhmät erottuvat muista organisaation ympäristössä toimivista tahoista, sekä millaisten ominaisuuksien perusteella sidosryhmien tärkeyttä arvioidaan OPPohjola-ryhmän näkökulmasta. Sidosryhmät ovat yrityksen ympäristössä toimivia ryhmiä tai tahoja, joiden asema sidosryhmänä perustuu yleensä niiden kykyyn vaikuttaa yrityksen menestykseen (esimerkiksi asiakkaat) tai oikeutettuun asemaan yrityksessä (esimerkiksi omistajat ja henkilökunta). Viimeaikaisissa sidosryhmiin keskittyvässä tutkimuksessa on tunnustettu sidosryhmien merkitys yritysten menestymisen kannalta. Toisaalta kaikkien sidosryhmien huomioimiseen perustuvalla liikkeenjohtamisella on myös eettisiä perusteita. Yleistyneen käsityksen mukaan yrityksellä on vastuuta myös muita tahoja, kuin omistajiaan kohtaan. Sidosryhmien laaja-alainen huomiointi on siis osa vastuullista liiketoimintaa ja sitä kautta yritysten yhteiskuntavastuun lähtökohta. Sidosryhmiä on pyritty määrittelemään lukuisilla eri tavoilla eri tutkijoiden toimesta. Erilaiset määritelmät ovat hämärtäneet sidosryhmän käsitettä jopa niin, että käytännössä kaikki yrityksen ympäristössä toimivat tahot voidaan nähdä yrityksen sidosryhmiksi. Yrityksen on kuitenkin hyödyllistä tunnistaa sen tärkeimmät sidosryhmät, jotta se voi toteuttaa suunnitelmallista sidosryhmäpolitiikka näihin tahoihin päin. Tämä tutkimus pyrkii luomaan yleiskuvan siitä, mitkä ovat OP-Pohjola-ryhmälle sen keskeiset sidosryhmät ja miksi. Tutkimus perustuu OP-Pohjola-ryhmässä työskentelevien henkilöiden teemahaastatteluihin. Haastattelumateriaalia on analysoitu käyttäen apuna sisällönanalyysiä ja sisällön erittelyä. Tutkimuksen teoreettisena viitekehyksenä toimii Mitchellin, Anglen ja Woodin ns. sidosryhmien identifikaation malli, jonka mukaan sidosryhmän tärkeys yrityksen näkökulmasta perustuu siihen, onko sidosryhmällä valtaa, legitiimi asema tai kiireellisiä vaateita suhteessa yritykseen. Sidosryhmien identifikaation mallin mukainen analyysi osoitti, että OP-Pohjola- ryhmän tärkeimmät sidosryhmät ovat asiakkaat sekä lainsäätäjät ja viranomaiset. Muita OP-Pohjola- ryhmän sidosryhmiä ovat omistajat, hallinto, media, henkilökunta, kansalaisjärjestöt ja palkansaajajärjestöt. Sidosryhmän tärkeyteen OP-Pohjola- ryhmän näkökulmasta näytti vaikuttavan eniten sidosryhmän kyky vaikuttaa organisaation menestykseen. Tämä kyky saattoi perustua joko välilliseen tai välittömään valtaa tai esimerkiksi asiantuntemukseen finanssialasta. Se, kuinka 'äänekäs' sidosryhmä on, ei yksistään vaikuta sidosryhmän tärkeyteen yrityksen näkökulmasta. Tutkimuksessa käytettiin lähteinä enimmäkseen 2000- luvulla tehtyjä sidosryhmätutkimuksia sekä teoreettista kirjallisuutta sidosryhmiin ja yritysten vastuullisuuteen liittyen.
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(2013)Tutkielmassa käsiteltiin opportunistista skedulointia mobiilissa langattomassa radioverkossa. Opportunistinen skedulointi pyrkii valitsemaan aina käyttäjän, jolla on parhaat tiedonsiirtokanavaolosuhteet kullakin valinnan hetkellä, jolloin saavutetaan parempi järjestelmän tiedonsiirtokapasiteetti verrattuna kiinteästi ennalta määriteltyyn skedulointijärjestykseen. Opportunistisen skeduloinnin haasteita ovat käyttäjien välisen reiluuden saavuttaminen sekä käyttäjä- ja palvelukohtaisten laatuvaatimusten huomioiminen. Skedulointi voidaan tehdä keskitetysti ja hajautetusti. Hajautetuissa skeduloinnin algoritmeissa voidaan luontevasti hyödyntää peliteorian tarjoamia formaaleja malleja. Myös kognitiiviset radiot ja LTE:n pienten solujen järjestelmät voivat hyödyntää vaihtelevia radiokanavaolosuhteita käyttämällä opportunistista skedulointia ja hajauttamalla skeduloinnin päätöksentekoa peliteoreettisia malleja hyödyntäen. Tutkielma sisältää kirjallisuuskatsauksen opportunistisesta skeduloinnista sekä kahden opportunistisen ja yhden ei-opportunistisen skedulointialgoritmin simulointitestit Matlab-ohjelmalla. Kirjallisuuskatsauksesta nähdään, että ilman opportunistista skedulointia ilmara-japinnan tiedonsiirtokapasiteetin hyödyntäminen jää huomattavan vajavaiseksi. Peliteorian soveltaminen tuo uusia mahdollisuuksia hajautettujen skedulointien ratkaisujen toteutuksille. Simulointitestit osoittivat kahden opportunistisen skedulointialgoritmin erot suorituskyvyssä ja reiluudessa sekä opportunistisen skeduloinnin paremman suorituskyvyn vaihtelevissa kanavaolosuhteissa verrattuna ei-opportunistiseen skedulointiin.
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(2019)Modern software systems increasingly consist of independent services that communicate with each other through their public interfaces. Requirements for systems are thus implemented through communication and collaboration between different its services. This creates challenges in how each requirement is to be tested. One approach to testing the communication procedures between different services is end-to-end testing. With end-to-end testing, a system consisting of multiple services can be tested as a whole. However, end-to-end testing confers many disadvantages, in tests being difficult to write and maintain. When end-to-end testing should adopted is thus not clear. In this research, an artifact for continuous end-to-end testing was designed and evaluated it in use at a case company. Using the results gathered from building and maintaining the design, we evaluated what requirements, advantages and challenges are involved in adopting end-to-end testing. Based on the results, we conclude that end-to-end testing can confer significant improvements over manual testing processes. However, because of the equally significant disadvantages in end-to-end testing, their scope should be limited, and alternatives should be considered. To alleviate the challenges in end-to-end testing, investment in improving interfaces, as well as deployment tools is recommended.
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(2023)Objective: We studied changes in eating behaviors over a 12-month period following bariatric surgery versus a dietary intervention. Methods: We examined eating behaviors through validated questionnaires (the Three-Factor Eating Questionnaire, the Dutch Eating Behavior Questionnaire, and the Binge-Eating Scale) in 120 bariatric surgery participants and 19 participants undergoing a dietary intervention. We also measured body weight, body composition (DEXA scan), and metabolic features (blood samples and OGTT), comparing the surgery and dieting groups before, at 5–6 months, and at 12 months, respectively, after the weight loss intervention began. Results: We observed greater weight loss and metabolic improvements following surgery compared with dieting. Surgery led to a decreased or unchanged eating restraint, while dieting accompanied increases in these eating behaviors. Both weight loss methods reduced disinhibited eating, binge eating, external eating, and hunger susceptibility. While surgery primarily led to a decreased hunger perception and sensitivity to external eating triggers, the dieting group acquired behaviors to cope with sustained hunger and eating triggers. Body weight at baseline and the amount of weight change over time may have affected the size of the behavioral changes. We found that per percentage of weight loss the size of behavioral changes was not different between diet and surgery groups. This implies that the amount of weight loss and the size of behavioral change may go hand in hand. Conclusions: Surgery led to less restrained eating, hunger susceptibility, and external eating, while after dieting, learnt behaviors were used to limit food intake.
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(2013)The neutral B_s meson consisting of \mathrm{\bar{b}} and s quarks can decay through the channel B_s → J/ψ Φ The B_s can on-flight mix with its antiparticle \mathrm{\bar{B}}_\mathrm{s} that can also decay to the J / ψΦ final state. The identification of the b quark flavour of the B_s meson at the production time is crucial for measurement of the phase Φ_s, a parameter describing the CP violation between the B_s meson eigenstates. Different types of flavour tagging methods have been developed to extract the initial flavour of decayed neutral B mesons. Since the b quarks at the LHC are produced as b\mathrm{\bar{b}} pairs, one method to identify the B_s flavour is to use muons that originate from decays of hadronised b quarks on the opposite side of the signal meson. In this work, the flavour tagging performance of muons from the opposite-side B hadron decays were studied. The flavour tagging was done for the B_s → J / ψΦ channel and the reference channel B^{+} → J / ψK^{+} with simulated B_s and B^{+} events as well as B^{+} data. This study verifies the flavour tagging performance obtained from simulated B_s events with real B^{+} data since flavour tagging cannot be directly done for B_s events reconstructed from the collision data. The tagging performances obtained from all the three samples are in agreement. The wrong tag fraction of the B^{+} data is (29 ± 0.8) %, the tagging efficiency is (4.03 ± 0.07) % and the tagging power is (0.65 ± 0.04) %. The tagging performance obtained from the B^+ data is compatible with the flavour tagging results obtained by the LHCb experiment.
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(2019)With the introduction of DNA sequencing over 40 years ago, we have been able to take a peek at our genetic material. Even though we have had a long time to develop sequencing strategies further, we are still unable to read the whole genome in one go. Instead, we are able to gather smaller pieces of the genetic material, which we can then use to reconstruct the original genome with a process called genome assembly. As a result of the genome assembly we often obtain multiple long sequences representing different regions of the genome, which are called contigs. Even though a genome often consists of a few separate DNA molecules (chromosomes), the number of obtained contigs outnumbers them substantially, meaning our reconstruction of the genome is not perfect. The resulting contigs can afterwards be refined by ordering, orienting and scaffolding them using additional information about the genome, which is often done manually by hand. The assembly process can also be guided automatically with the additional information, and in this thesis we are introducing a method that utilizes optical maps to aid us assemble the genome more accurately. A noticeable improvement of this method is the unification of the contigs, i.e. we are left with fewer but longer contigs. We are using an existing genome assembler called Kermit, which is designed to accept genetic maps as auxiliary long range information. Our contribution is the development of an assembly pipeline that provides Kermit with similar kind of information via optical maps. The initial results of our experiments show that the proposed genome assembly scheme can take advantage of optical maps effectively already during the assembly process to guide the reconstruction of a genome.
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(2022)This thesis examines the optical response of tuneable chiral plasmonic nanostructures in linear cross-polarization. Plasmonic gold-silver nanostructures composed of silver-coated gold nanorods, and dynamic DNA origami are investigated because of their optical properties of interest in the visible light wavelength region, and because of their controllable rotational asymmetry, which results in tuneable chirality in dimer structures. These plasmonic nanostructures present optical properties such as circular dichroism and optical rotatory dispersion. In this thesis we establish the relationship between perceived color, spectrometry, circular dichroism and optical rotatory dispersion of the samples, depending on the chiral geometry of the nanostructures within. The motivation is to predict perceived color from the chiral geometry of the nanostructures, which will enable visual detection for biosensing applications. Circular dichroism and optical rotatory dispersion give us detailed knowledge about the polarization state of a sample, but visible light detection and spectrometer measurements are more accessible and portable methods for characterizing the polarization state of a sample. We achieve color modulation from green to blue with the switching of chiral geometry, under cross-polarized white light. This has potential for biosensing applications, based on the perceived color change depending on the chiral geometry of the sample. The DNA origami structures react to the presence of an analyte by changing their chiral geometry. Possible applications in biosensing of analytes can be made more practical if the orientation of the DNA origami template can be determined from the perceived color or the transmission spectra, rather than from the less accessible circular dichroism or optical rotatory dispersion measurements.
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(2020)Modulimuodot ovat tietyt ehdot täyttäviä kuvauksia ylemmässä kompleksisessa puolitasossa. Modulimuodoilla on Fourier-kehitelmät, joissa ensimmäisen kertoimen ollessa 0 modulimuotoa kutsutaan kärkimuodoksi. Ramanujanin tau -kuvaus on määriteltävissä muun muassa painoa 12 olevan kärkimuodon Fourier-kehitelmän kertoimien avulla. Tässä tutkielmassa tarkastelemme eksponenttisummia, joiden kertoimet ovat Ramanujanin tau -kuvauksen arvoja, ja käymme läpi Matti Jutilan vuonna 1987 julkaiseman tuloksen, joka parantaa J. R. Wiltonin vuoden 1929 asymptoottista arviota näille summille optimaaliseen muotoon. Tutkielmassa syvennytään osaan Jutilan sivuuttamista yksityiskohdista ja pyritään selkiyttämään todistuksen yleistä rakennetta. Tutkielmassa myös huomataan, että Ramanujanin tau -kuvauskertoimiset eksponenttisummat muodostavat tuloksesta erityistapauksen, ja tulos on yleistettävissä koskemaan kaikkia eksponenttisummia, joissa kertoimet ovat jonkin kärkimuodon Fourier-kehitelmän kertoimia.
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(2007)Optimal Punishment of Economic Crime: A Study on Bankruptcy Crime This thesis researches whether the punishment practise of bankruptcy crimes is optimal in light of Gary S. Becker’s theory of optimal punishment. According to Becker, a punishment is optimal if it eliminates the expected utility of the crime for the offender and - on the other hand - minimizes the cost of the crime to society. The decision process of the offender is observed through their expected utility of the crime. The expected utility is calculated based on the offender's probability of getting caught, the cost of getting caught and the profit from the crime. All objects including the punishment are measured in cash. The cost of crimes to the society is observed defining the disutility caused by the crime to the society. The disutility is calculated based on the cost of crime prevention, crime damages, punishment execution and the probability of getting caught. If the goal is to minimize the crime profits, the punishments of bankruptcy crimes are not optimal. If the debtors would decide whether or not to commit the crime solely based on economical consideration, the crime rate would be multiple times higher than the current rate is. The prospective offender relies heavily on non-economic aspects in their decision. Most probably social pressure and personal commitment to oblige the laws are major factors in the prospective criminal’s decision-making. The function developed by Becker measuring the cost to society was not useful in the measurement of the optimality of a punishment. The premise of the function that the costs of the society correlate to the costs for the offender from the punishment proves to be unrealistic in observation of the bankruptcy crimes. However, it was observed that majority of the cost of crime for the society are caused by the crime damages. This finding supports the preventive criminal politics.
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(2023)Finnish school choice policy is primarily an urban phenomenon. In practice, it is only possible in a few municipalities that have sufficient infrastructure for school markets. The municipalities in the capital region in particular face challenges of growing segregation manifested in socio-economic disparities, residential areas, and schools. The municipalities in the capital region have ended up with very different solutions when evaluating the most suitable school choice environment for their respective municipalities. One significant recent factor in shaping the current state of Finnish school choice policy is the Basic Education Act of 1999, which has partly enabled the development of various school choice environments between municipalities. The focus of the study is on the types of solutions that have been made in the municipalities of the capital region regarding the school choice environment, the desired future of the school choice environment in the municipalities, and how these goals are justified. For my Master's thesis, I used interview data collected in the School Markets and Segregation - The Societal Cost of School Choice research project. The data is the most recent interview material available, and it includes interviews with educational policy actors in the capital region. A total of nine educational policy actors from the capital region were interviewed for the study. Of the interviewees, three hold senior positions in metropolitan municipalities, three are in administrative positions in different municipalities, and three are members of municipal education boards. In analyzing the interview data, I employed two concepts by Kenneth Burke: "the Idea of the Negative" and the "Dramatistic Pentad" as analytical tools. Overall, the school choice environments in the examined municipalities differed from each other, and the current school choice environment seemed to be linked to the desired future school choice environments in the municipalities. The new frameworks for school choice environments formulated by the interviewees in the interview data varied to some extent based on the current school choice environment in the municipalities. The new frameworks for school choice environments outlined by the municipalities differed from each other. However, despite the current frameworks for school choice environments, there were a few common aspects that connected all municipalities regarding the new frameworks as well. None of the municipalities desired the public disclosure of school-specific learning outcomes or a completely unrestricted and unregulated new school choice environment.
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(2016)The aim of this thesis was to define optimal packaging conditions for four fresh ready-to-cook and pre-cut vegetable mixes. The packaging conditions consisted of perforated and non-perforated film which were investigated in two different gas mixtures. One of the gas mixtures consisted of modified atmosphere which was chosen in advance and the other gas mixture consisted of normal atmosphere. The literature study focused on the negative influences of processing methods on the physiological properties of vegetables. The main principles of packaging solutions by which negative influences of fresh-cut produce could be minimized with were also mentioned. The main target of the experimental study was to examine if perforated films could be used for avoiding of in-package anaerobic respiration which is a common reason for vegetable spoilage. The respiration rates of the products were measured and with the results an optimally perforated film was defined for each product. The gas concentrations were measured electronically and the quality of the products were evaluated with sensory evaluations and microbiological determinations. Electronically measured gas concentrations were verified gas chromatographically and also the water vapour transmission properties of the films were studied. With perforated film and modified atmosphere gas concentrations remained most constant and they were mainly held in aerobic respiration level. With other packaging solutions very low oxygen levels and very high carbon dioxide levels were observed which was also noticed in the sensory evaluations where off-odours and off-flavours were discovered. With perforated film and modified atmosphere the growth of yeasts, molds and bacteria was smaller than with perforated film and normal atmosphere. The verification of the gas measurements was successful and gas concentrations which were measured both electronically and gas chromatographically were on the same range though minor differences in the accuracy of the results were discovered. The most optimal packaging solution for tested products was achieved with perforated film and modified atmosphere.
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(2023)The scholarship allotment problem describes the goal of strategically offering scholarships to prospective students of a university in a way that optimises the expected return for that investment. The goal of this thesis is to formulate the scholarship allotment problem in multiple variations of increasing complexity while also introducing algorithms to solve those variations optimally as efficiently as possible. The thesis also offers some insight into the way more complex variations and generalisations heighten the difficulty of finding an optimal solution in a reasonable amount of time. The main focus and the main tool used to tackle these problems is the classic knapsack algorithm and different variations of it, like multiple-choice knapsack and multidimensional knapsack. In addition to the theoretical side, the thesis contains an empirical study into the performance and feasibility of the algorithms introduced. Concrete implementations of the algorithms discussed are all available on a public GitHub repository online: https://github.com/SirVeggie/scholarship-allotment.
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(2015)This study applies two novel forest economic models to analyze the effect of optimal carbon storage on the choice between clearcuts and continuous cover forestry. Unlike previous studies, we determine the economically optimal management regime endogenously, by optimization. We study a policy where the society pays forest owners a Pigouvian subsidy for the carbon that is sequestered by the stand as it grows. The focus of our analysis is a subsidy system that also takes into account the carbon both stored in and released from wood products. In the first part of the thesis, the question of optimal carbon storage is studied using a continuous time biomass model that does not include any a priori assumptions on clearcuts vs. continuous cover forestry. We show analytically that subsidized carbon sequestration postpones thinning and increases optimal stand volume along the rotation. With high carbon price the shadow value of stand volume becomes negative. Numerical results show that carbon prices within a realistic range may switch the optimal management regime from clearcuts to continuous cover management. A higher interest rate can lead to a higher stand volume and a longer optimal rotation, which contrasts the results of the classic Faustmann model. Next, the question is studied applying a more detailed size-structured transition matrix model based on empirically estimated Scandinavian growth data. This approach produces a more accurate description of the complex dynamics of uneven-aged stands and optimization of harvesting activities. According to numerical results, thinning is invariably carried out from above, and the size of the harvested trees increases with carbon price. Optimal rotation age increases with carbon price, and moderate carbon pricing is sufficient to switch the management regime to continuous cover management. Optimal rotation age also increases with interest rate. Clearcut management is the more competitive, the more productive is the site type. Both models suggest that carbon storage has a significant effect on optimal forest management, and that it typically favors continuous cover forestry. Similar analysis on optimal carbon storage in forestry has not been presented before. We also discuss various carbon subsidy systems in the context of developing climate policy.
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(2014)The need to understand causes behind business cycles and inflation, and their link to prevailing monetary policy is today essential. During recent years, the family of Dynamic Stochastic General Equilibrium (DSGE) models has emerged as the workhorse for characterizing these phenomena and their interlinkage, allowing a detailed, structurally microfounded modelling of economys general equilibrium and its dynamic response to exogenous, stochastic shocks. Traditionally, a central bank is assumed to be able to carry out its monetary policy influence towards the economy by altering the value of its conventional instrument, the nominal short-term interest rate. In the light of the recent financial crisis pushing those interest rates very low towards their zero lower bound, there has been a need, and correspondingly significant research towards designing unconventional instruments, with which a control could be retained also in the event of short-term interest rates becoming ineffective. One of these alternatives is called quantitative easing, which involves buying of government issued bonds. This Thesis presents a stylized, closed economy DSGE macromodel with nominal Calvo rigidities both in prices and wages. The model also incorporates a stylized financial sector. It then discusses how monetary policy instruments, namely the conventional nominal short-term interest rate, but also more unconventional government asset purchases, can be used in steering the economy in the presence of an exogenous shock shifting it away from its initial equilibrium. We simulate the developed macrosystem in the presence of exogenous shocks, and optimize the rules according to which the central bank uses its two instruments. Our results indicate that co-ordination between interest rate setting and quantitative easing is optimal, but before concluding on any specific policy principles, care should be taken in calibrating both the model of the economy and the metric evaluating welfare effects of the policy.
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(2019)Forests have a significant role in preventing climate change. Forests work as a carbon sink and produce also other non-timber amenity values alongside commercial timber. Taking these non-timber amenity values into account while calculating the value of forest will have an effect on choosing an optimal forest management regimes. The Faustmann formula and its extensions are widely explored among forest economists. Most notable extensions of the Faustmann formula include the Hartman extension of non-timber amenity values and the inclusion of carbon storage. Both the Hartman model and the Faustmann model with carbon storage, have previously only been analytically studied separately. In this study, the original Faustmann model, Faustmann model with carbon storage, Hartman model and Hartman model with carbon storage is covered. The entirely novel optimal conditions for the unique and finite rotations for these models are presented. In addition, based on empirically estimated ecological growth models, the numerical examples for all of the economic models included in this study is presented. According to the results, extending the classical Faustmann model to cover carbon storage or (and) non-timber amenity values, lengthens the optimal rotation and increases the bare lad value. Additionally, weaker growing conditions always increase the optimal rotation. Moreover, increasing the interest rate may increase or decrease the rotation, depending on the carbon price.
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(2013)The optimal harvesting for a set of even-aged Dahurian Larch (Larix gmelinii) stands located in Aershan area of the northeast of Inner Mongolia, China, are studied. The effects of catastrophic pest outbreaks (i.e. Siberian moth) on the optimal harvesting plan are also studied, and the comparison on these two cases, namely deterministic and stochastic, are analyzed. The simulation is based on an individual-tree diameter growth model, an individual-tree height model, and model for the tree mortality for the coming 5-year period. Combined with the simulation system, the optimization model modified from Hyytiäinen et al. (2005) is able to find the number of thinnings, intensity of thinning, type of thinning, subject to given rotation lengths. In even-aged management, the objective variable is the bare land value with 3.5% discount rate. In addition, a scenario approach is applied when simulating the effects of catastrophes, i.e., pest outbreaks. Stochasticity here is represented by a set of scenarios. The timing of an insect outbreak is random. In order to know the frequency of insect outbreak, an exponential model is applied. The numerical results indicate that the probability that an outbreak at epidemic level will occur within an interval of 5 years is about 0.39. Within a 10-year interval the probability is about 0.63. It is nearly certain that an outbreak at epidemic level occurs within 45 years. The optimal solutions are presented separately for deterministic and stochastic cases. For the deterministic case, the results indicate that high bare land values were associated with stands of high basal area, tree diameters and height. Typically, the higher the mean annual increment and the site quality, the higher the bare land value. Meanwhile, the results show that the optimal rotation may vary considerably (40-58 yrs) at 3.5% interest rate depending on the initial stand state. In the stochastic case, considering the effect of catastrophe of pest outbreak, numerical results show that the optimum roation is shortened and the mean values of bare land value are about 14.8% to 25.6% lower compared with the deterministic case.
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(2013)This thesis studies the economically optimal timing of thinnings and final harvest on Costa Rican Tectona grandis plantations. Consequently this thesis studies the profitability of the plantations and makes a comparison to previous studies. Optimization is based on programming with AMPL with Knitro optimizing software. The objective function used is the Faustmann formula. Different rates of interest are used. The ecological functions used for the modeling were obtained from previous studies by Pérez and Kanninen (2005a). The economic data such as planting and thinning costs and log prices were obtained from a T. grandis plantation specialist. The results of the study show that the optimal harvesting regime in T. grandis plantations differs from what is suggested in literature. The main findings are that the optimal rotation length is shorter and both timing and intensity of the thinnings vary depending on the rate of interest used. In addition the maximized bare land values under optimal management regimes are notably higher than bare land values under previously suggested management regimes. The management regime is highly sensitive to the rate of interest used. The management regime is less sensitive to the changes in price than expected. This thesis suggests that the initial density of 816 ha-1 trees results into higher bare land values than 1111 ha-1 trees . However, the difference is minor and possible increase in silvicultural costs is not considered. In addition a simple test is carried out to see the possible effects on heartwood proportion growth to the optimal management regime. The shortcomings and possibilities to improve the model are discussed. It is noted that the price data for T. grandis is not coherent, and that the ecological model could be improved in order to increase its accuracy.
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(2013)This study analyzes the optimal harvesting of single species uneven-aged Norway spruce (Picea abies (L.) Karst.), Scots pine (Pinus sylvestris L.), and birch (Betula pendula Roth. and B. pubescens Ehrh.) stands, in addition to mixed species stands with all three species. The analysis is based on an economic description of uneven-aged forestry using a size-structured transition matrix model and a single-tree model. The optimization problem is solved in its general dynamic form using gradient-based interior point methods. Similar analysis on uneven-aged birch, Scots pine and mixed species stands in Nordic conditions has not been published. Increasing the harvesting interval decreases the average annual volume yield. Assuming natural regeneration, this suggests that volume yield is maximized by uneven-aged rather than even-aged management. The present value of stumpage revenues is maximized after saw timber and pulpwood prices, interest rate, and a 15-year harvesting interval are included. The economically optimal solution with a 3% interest rate produces an annual yield of 1.9, 5.5 and 2.9 cubic meters (m3) for Scots pine, Norway spruce, and birch respectively in single species stands at site with average productivity. At less productive sites, the mixed species stand is heavily dominated by Norway spruce regardless of interest rate. At more productive sites on the other hand, increasing interest rate increases species diversity. Both the optimal volume yield and net present value maximization solutions converge to unique species- and site-type-specific steady-states with constant harvests. The transition matrix model typically used in optimization studies is computationally less demanding than the single-tree model, but the differences in optimal solutions are more remarkable than earlier studies show. Additionally, it appears that the investmentefficient optimization model may result in steady-state solutions that significantly differ from the correct solutions.
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(2011)The objective of this thesis is to examine the economic effects in the conflict between grey seal population and the salmon fishery in the Baltic Sea. We will formulate a bioeconomic model which provides new insights on the optimal management of Atlantic salmon with respect to the effects brought about by the grey seal population. As the catch losses caused by seals have an effect on salmon fishery in Baltic, we will study how seal population affects the present value of the salmon fishery. The study considers the Finnish coastal trap net fishery. The bioeconomic model considers a scenario of sole salmon fishery and a scenario of salmon fishery affected by the grey seal population. On the basis of these scenarios, a seal compensation scheme is introduced. We can observe a significant economic seal-induced effect on the salmon fishery. The results suggest that the present seal compensation scheme emploid by the Finnish government is suboptimal. This thesis is part of the TARMO –project, in which the conflict between grey seal population and salmon fishery is studied using the methods of environmental economics.
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