Dense Packings of Congruent Circles in Rectangles with a Variable Aspect Ratio

We use computational experiments to find the rectangles of minimum area into which a given number n of non-overlapping congruent circles can be packed. No assumption is made on the shape of the rectangles. Most of the packings found have the usual regular square or hexagonal pattern. However, for 1495 values of n in the tested range n =< 5000, specifically, for n = 49, 61, 79, 97, 107,... 4999, we prove that the optimum cannot possibly be achieved by such regular arrangements. The evidence suggests that the limiting height-to-width ratio of rectangles containing an optimal hexagonal packing of circles tends to 2-sqrt(3) as n tends to infinity, if the limit exists.Comment: 21 pages, 13 figure

Power plant carbon dioxide emission quantification with plume modeling

The quantification of carbon dioxide emissions pose a significant and multi-faceted problem for the atmospheric sciences as a part of the research regarding global warming and greenhouse gases. Emissions originating from point sources, referred to as plumes, can be simulated using mathematical and physical models, such as a convection-diffusion plume model and a Gaussian plume model. The convection-diffusion model is based on the convection-diffusion partial differential equation describing mass transfer in diffusion and convection fields. The Gaussian model is a special case or a solution for the general convection-diffusion equation when assumptions of homogeneous wind field, relatively small diffusion and time independence are made. Both of these models are used for simulating the plumes in order to find out the emission rate for the plume source. An equation for solving the emission rate can be formulated as an inverse problem written as y=F(x)+ε where y is the observed data, F is the plume model, ε is the noise term and x is an unknown vector of parameters, including the emission rate, which needs to be solved. For an ill-posed inverse problem, where F is not well behaved, the solution does not exist, but a minimum norm solution can be found. That is, the solution is a vector x which minimizes a chosen norm function, referred to as a loss function. This thesis focuses on the convection-diffusion and Gaussian plume models, and studies both the difference and the sensibility of these models. Additionally, this thesis investigates three different approaches for optimizing loss functions: the optimal estimation for linear model, Levenberg–Marquardt algorithm for non-linear model and adaptive Metropolis algorithm. A goodness of different fits can be quantified by comparing values of the root mean square errors; the better fit the smaller value the root mean square error has. A plume inversion program has been implemented in Python programming language using the version 3.9.11 to test the implemented models and different algorithms. Assessing the parameters' effect on the estimated emission rate is done by performing sensitivity tests for simulated data. The plume inversion program is also applied for the satellite data and the validity of the results is considered. Finally, other more advanced plume models and improvements for the implementation will be discussed

Kylmä kvarkkiaine QCD häiriöteoriassa

We study a system of cold high-density matter consisting purely of quarks and gluons. The mathematical construction of Quantum Chromodynamics (QCD) introduces interactions between the fields, which modify the thermodynamic properties of the system. In the presence of interactions, we can not solve the thermodynamic properties of the system analytically. The method is to expand the result in a series in terms of the QCD coupling constant. This is referred to as the perturbation theory in the context of thermal field theory (TFT). The coupling constant describes the strength of the interaction. We introduce the basic calculation methods used in the QCD and the TFTs in general. We will also include the chemical potential associated with the number of quarks in the system in the calculation. In the case of zero temperature, quarks form a Fermi-sphere such that energy states lower than the chemical potential will be Pauli blocked. The resulting fermionic momentum integrals are modified as a consequence. We can split these integrals into two parts, referred to as the vacuum and matter parts. We can split the calculation of the pressure into two distinct contributions: one from skeleton diagrams and one from ring diagrams. The ring diagrams have unphysical IR divergences that we can not cancel using the counterterms. This is why hard thermal loop (HTL) effective field theory (EFT) is introduced. We will discuss this HTL framework, which requires the computation of the matter part of the gluon polarization tensor, which we will also evaluate in this thesis

Designing and making in a school context:a process model and practical insights

Abstract. Teaching 21st century skills, STEM (science, technology, engineering, mathematics) subjects and programming for children is the future in education. This thesis was inspired by the project ordered by INTERACT research unit from the University of Oulu, and the goal was to familiarize school children with programming and digital fabrication while collecting research material for INTERACT research unit. Research unit wanted a research material on a project that combines design and making in school context and utilizes University of Oulu Fab Lab. The idea was to conduct a making (digital fabrication) project with children and research it. This thesis is based on the experiences of the project and aims to answer a research question: “What kind of process model supports design and making in school context?”. This research was done using qualitative research methods. This thesis views the social aspects of people in the school system, their relationships, goals, and actions. A lot of data was collected about human beings, their experiences, and reflections. Sessions with children were video and audio recorded but also reflected by project members and children themselves. Gathered data was analyzed using content analysis. The main result of this thesis is a reflective design process model that supports design and making in the school environment. In addition to that, this thesis explain what kind of actors are involved in the process, such as children, teachers, schools, researchers, parents, university and so forth. It describes the goals that needs to be taken into account; most importantly from curriculum and teaching point of view, but also from the IT (Information Technology) point of view. This process could generate more skillful programmers, designers, makers, if this kind of design and making projects could be introduced to school environment. Thesis also enlightens the working in the school context and the pros and cons relating to it. School context is best for projects that focus more on learning goals than end results and outcomes. Results are finally analyzed in light of having digital fabrication and making part of everyday school work

Moses: Freud's ultimate project

Moses and Monotheism&nbsp;was the last work of&nbsp;Sigmund Freud, known as the founder of psychoanalysis. It is not a study of psychoanalytical issues, but mainly a study of the biblical figure Moses, albeit with psychoanalytical applications. Freud attempted to prove that Moses’ original monotheistic religion, which he, an Egyptian, gave to the Israelites, was one without sacrifices and priests, whereas the Israelite religion known from the Bible was not even strictly monotheistic. Moses’ religion, according to Freud, was the religion of Ikhnaton, the similarity of which to Israelite religion Freud was in fact among the first to realize. The religion of Moses, which Freud thought he was able to reconstruct, was in my view actually Judaism, which later developed from Israelite religion. Freud was a stern atheist, but nevertheless also an uncompromising Jew, who never thought atheism would exclude Jewishness. As such he stands as a fine example of Judaism being something more and other than religion and ethnicity. Freud worked on&nbsp;Moses and Monotheism&nbsp;during his five last years. What apparently motivated him was Hitler’s rise to power in Germany, which presented a threat to Freud personally as well as to his life’s work, since the Nazis outlawed psychoanalysis. This threat became a reality when Germany occupied Austria in 1938. Freud fled to London where he finished Moses and Monotheism, published only months before his death in September 1939. In this work Freud’s appreciation of Judaism finds a remarkable expression

Autenttisuus japanilaisten silmin: Ruka-Kuusamon aitouden säilyttäminen matkailukohteen suosion kasvaessa

Ruka-Kuusamon matkailualueen suosio on ollut voimakkaassa kasvussa viime vuosien aikana ja matkailualue vetää puoleensa vuonna 2018 enemmän japanilaisia kuin koskaan aikaisemmin. Aitous ja lämminhenkisyys, Ruka-Kuusamon vetovoimatekijät, halutaan säilyttää matkailukohteen nopeassa kasvussa. Autenttisuuden säilymisen haasteeseen etsitään kestäviä ratkaisuja tämän tutkimuksen avulla. Aihetta tarkastellaan japanilaisten matkailijoiden näkökulmasta. Tämän haasteen ratkaisemiseksi selvitettiin niitä tekijöitä, jotka tekevät Ruka-Kuusamosta aidon ja ainutlaatuisen. Tavoitteena oli kartoittaa luontokokemuksen ja ohjelmapalveluiden välistä suhdetta ja selvittää, vastaavatko alueen ohjelmapalvelut japanilaisten matkailijoiden kokemusta alueen aitoudesta vai toimivatko ne sitä vastaan. Tutkimuksen avulla saatiin selville, miten palveluita tulisi jatkossa kehittää, jotta kohde onnistuisi säilyttämään aitoutensa, ja sitä kautta houkuttelevuutensa matkailijoiden keskuudessa. Opinnäytetyö toteutettiin toimeksiantona Naturpolis Oy:lle. Tutkimuksen teoreettinen viitekehys on jaettu kolmeen osaan, jotka ovat seuraavat: Ruka-Kuusamo, autenttisuus ja elämyksellisyys matkakohteissa sekä japanilaiset matkailijoina. Työ toteutettiin kvalitatiivisena tutkimuksena teemahaastattelujen avulla. Mahdollisimman luotettavan tutkimustiedon saamiseksi rukakuusamolaisia yritysten edustajia ja Ruka-Kuusamossa matkailevia japanilaisia haastateltiin paikan päällä. Tutkimustuloksista ilmeni Ruka-Kuusamon olevan edelleen autenttinen matkailukohde sekä japanilaisten että yritysten edustajien mielestä. Ainutlaatuisimmaksi tekijäksi korostui luonnon erityisyys. Japanilaisille autenttisuuden ilmentyminen liittyy vahvasti luontokokemuksiin. Ruka-Kuusamon ohjelmapalvelut vastaavat japanilaisten kokemusta alueen aitoudesta. Kehitysehdotukset autenttisuuden säilyttämiseksi kohteessa keskittyvät laadun ylläpitämiseen, ruuhkautumiseen, paikallisuuteen, mielikuviin, luontokokemuksiin ja luonnontilaan.The popularity of the Ruka-Kuusamo tourism region has had rapid growth in recent years and the area is attracting more Japanese travelers than ever before. Genuinity and warmth are things that want to be retained while the destinations popularity is growing rapidly. The aim of this research is to find sustainable solutions for the challenge of retaining authenticity in the Ruka-Kuusamo region. The subject of the study is viewed from the perspective of Japanese tourists. This research examines the factors that make Ruka-Kuusamo unique and authentic. The aim was to view the relation between nature experiences and activity services. The purpose was to find out whether the current activity services correspond to Japanese travelers’ experience of the destinations authenticity. The study was used to find out how services should be developed in ways that would preserve authenticity, and consequently, the attractiveness of the destination. The commissioner of the thesis is Naturpolis Oy. The theoretical framework of the study is divided into three parts: Ruka-Kuusamo, Japanese tourists, as well as authenticity and experiental experiences in destinations. The study was carried out as a qualitative research by means of theme interviews. In order to get reliable information, the interviews took place in Ruka-Kuusamo and the interviewees were local businesses and Japanese tourists traveling in the area. The research results confirmed that Ruka-Kuusamo continues to be an authentic tourism destination. The factor that was most emphasized in the study was the unique nature of the area. According to the Japanese, the authenticity of Ruka-Kuusamo is strongly related to nature experiences. Results showed that the activity services in the region correspond to the Japanese experience of authenticity. The development proposals of the study concentrated on preserving authenticity in the destination. The factors emphasized were locality, the upkeep of quality, overcrowding, mental images, nature experiences, and the natural state

Future visions of adult education centers - SoMe times?

Siirretty Doriast

5. luokkalaisten kokemuksia viestinnästä sosiaalisessa mediassa ja toimintaideoita kiusaamiseen puuttumiseksi

Opinnäytetyössä tutkittiin Möysän ja Kirkonkylän koulujen viidennen luokan oppilaiden kokemuksia viestinnästä sosiaalisessa mediassa. Tutkimuksen tavoitteena oli selvittää haastattelemalla, mitä oppilaat sosiaalisessa mediassa viestivät, minkälaisissa viestintäpalveluiden ryhmissä he ovat mukana ja miten ryhmät muodostuvat. Tavoitteena oli kehittää toimintaideoita sosiaalisen median viestintäpalveluiden kautta tapahtuvaan kiusaamiseen puuttumiseksi oppilaiden näkökulmasta. Lisäksi opinnäytetyössä esiintyy oppilaiden kokemuksia liittyen viestinnän sävyeroihin ja epäasialliseen viestintään. Opinnäytetyön tarkoituksena oli selvittää koululaisten sosiaalisten suhteiden muodostumista ja vuorovaikutusta sosiaalisessa mediassa Lahden kaupungin hyvinvointiryhmän kehittämistyön tueksi. Opinnäytetyö on laadullinen tutkimus. Aineistonkeruu tapahtui teemahaastattelun avulla. Haastatteluiden teemat ja teemoihin liittyvät kysymykset oli mietitty etukäteen, mutta haastattelutilanteessa kysymysten järjestystä oli mahdollista muuttaa. Kokonaisuus muodostui kolmesta teemasta, joiden alla oli yhteensä 11 kysymystä ja yksi Case-työskentely. Haastattelut toteutettiin ryhmähaastatteluina, jolloin kummastakin luokasta muodostettiin neljä ryhmää. Tutkimukseen osallistui yhteensä 41 oppilasta, 18 Kirkonkylän koulusta ja 23 Möysän koulusta. Haastattelut litteroitiin ja analyysimenetelmänä käytettiin teemoittelua. Tulosten perusteella voidaan todeta, että oppilaat käyttävät sosiaalisen median viestintäpalveluista eniten WhatsAppia. Ryhmien muodostumisessa ei ollut selkeää tapaa, mutta niitä muodostetaan huvikseen tai tietyn tarkoituksen mukaan. Viestien sisältö koostuu kuvista, teksteistä ja videoista. Oppilaiden kokemuksien perusteella nettikiusaamista esiintyy vähän, mutta väärinymmärryksiä sen sijaan enemmän. Kiusaamistilanteissa eniten luotetaan opettajaan ja omiin vanhempiin, oppilaat nostivat esiin myös poliisin roolin. Opinnäytetyön tulokset ovat Lahden kaupungin itäisen palvelualueen hyvinvointiryhmän ja koulujen opettajien hyödynnettävissä.This bachelor’s thesis deals with fifth graders’ experiences of communication in social media. The aim of the study was to discover what kind of content the students share in communication applications, what kind of communication groups they use and how those groups are formed. In addition, the aim was to develop ideas from students’ perspective on how to intervene in cyberbullying. The thesis contains the students’ experiences of misunderstood messages and inappropriate behavior in communication groups. The objective was to acquire knowledge about the formation of social relations and interaction in social media. The study was conducted in order to support welfare work among children and adolescents in Lahti. The thesis was done using qualitative methods of research. The data of the study was collected with theme interviews. There were three themes, and 11 questions and one case study for each theme. The interviews were carried out as group interviews. Four groups were formed from each class. A total of 41 students participated in the study, 18 students from school Kirkonkylä and 23 students from school Möysä. The research showed that the most common application to use is WhatsApp.There is no specific pattern for forming groups. The groups are formed for pleasure or in order to share important things. Messages contain text, images and videos. Based on the answers, interviewed students have not experienced cyberbullying almost at all. However, misunderstandings are more common. The students’ wish was that parents and teachers intervene in cyberbullying. They would also trust the police. The results of this study can be used for Lahti welfare work and by teachers in schools