TTA310-ANTENNA-PIIRIKORTIN REFLOW-JUOTOSPROSESSIN OPTIMOINTI

Tämän insinöörityön toimeksiantaja Tracker Oy on yksi maailman merkittävimmistä eläinpaikannuslaitteiden valmistajista. Yritys on toiminut alalla jo kolmekymmentä vuotta. Pääkonttori, suunnittelu ja tuotekehitys sekä valmistus sijaitsevat Oulunsalossa. Myyntikonttoreita ja edustuksia on ympäri maailmaa. Insinöörityössä keskityttiin yhden uuden tuotteen reflow-juotosprosessin ohjelman tekoon ja muokkaamiseen juotoskoneelle. Juotosohjelma oli luotava lyijyttömiä materiaaleja ja juotteita varten. RoHSdirektiivin tultua voimaan 1.7.2006 lyijyä sisältäviä elektroniikkalaitteita ei saa enää tuoda Euroopan markkinoille. Juotosohjelma luotiin aikaisempia juotosohjelmia hyväksi käyttäen. Juotosprofiilin mittauksessa oli käytössä Kajaanin ammattikorkeakoulun profiilinmittauslaitteisto SuperMOLE. Juotosjäljen tutkimisessa käytettiin lisäksi koulun tetauslaboratorion Phoenix X-ray -analysaattoria. Molemmat laitteet tulivat työn edetessä erittäin tutuiksi työkaluiksi. Ongelmia työssä aiheutti lähinnä työn kohteena olevan piirikortin komponenttivalikoima. Kortilla olevat komponentit olivat kooltaan hyvin erikokoisia, joten niiden juotokseen tarvittava lämpömäärä oli niin erilainen. Lisäksi vaikeuksia tuottivat juotoskoneiden pienet tehot. Tuloksena saatiin toimiva juotosohjelma työn kohteena olevalle piirikortille. Sen lisäksi löytyi aikaisemmin käytössä ollutta juotospastaa paremman juotostuloksen aikaansaava pasta, jonka toimeksiantajayritys otti ensisijaiseksi juotteeksi tuotantoonsa.This Bachelor’s thesis was made for Tracker Oy. The objective of the thesis was to develop an optimal reflow profile for one new PCB. Because of RoHS directive, lead-free technology was taken into use on 1st of July 2006. Therefore, the profile of this process had to be made lead free. Tracker Oy, which was established in 1977, is specialized in tracking and telemetry devices. Tracker’s animal tracking solutions are based on three main technologies: radio tracking devices, GPS/GSM positioning devices, and software for these solutions. In this field Tracker Oy is a leading pioneer in the whole world. Previously created leaded soldering programs were used in this process. The temperatures and profile duration had to be changed for lead-free soldering. Lead-free technology caused a lot of problems. For instance, the process temperatures tend to rise considerably and the power of the used soldering machines seemed to be too low. In the profile measurement and inspection, the equipments of Kajaani University of Applied Sciences was used. For example, the thermal profiler Super MOLE and Phoenix X-ray analyzer from the production and testing laboratory were used. As a result of the thesis, an excellent reflow soldering program was made. A new, better solder paste was found, of which Tracker Oy took as their primary Pb-free solder paste

The influence of content knowledge on pedagogical content knowledge – the case of teaching photosynthesis and plant growth

The aim of the research was to investigate the effect of the amount and quality of content knowledge on pedagogical content knowledge (PCK). The biological content photosynthesis and plant growth was used as an example. The research sample consisted of 10 primary and 10 secondary (biology) teacher students. Questionnaires, lesson preparation task and an interview were used to collect data. Primary student teachers' were not aware of students’ conceptual difficulties and had problems in choosing the most important content. Neither of the groups had knowledge on suitable experiments and demonstrations, which indicates that PCK should be explicitly taught. The usefulness of PCK and some related constructs in initial teacher training is discussed

Joustavat asuinympäristöt: 10 visiota aikaa kestävään kaupunkiasumiseen

Housing production is usually based on the belief of predictability, but this approach is inconsistent with the fact that the future cannot be predicted. Residential design and construction must therefore adopt more flexible and adaptable principles, where the impossibility of making predictions is taken into account. Adaptable housing can help to meet the forthcoming and increasingly diverse housing needs, providing housing alternatives in a sustainable way. Ten visions presented in this publication introduce a wide range of means, methods and scales to achieve adaptability and flexibility in housing construction. The publication consists of ten design assignments created during an advanced housing design course at Tampere University of Technology in spring 2013. The publication presents not only a wide range of means to achieve flexibility in housing construction, but also their direct connection with the practice. The publication is part of a study concerning user-centric spaces in the Indoor Environment Program of RYM Oy

The Interplay of Thematic and Ludological Elements in Western-Themed Games

The Wild West has been productized and remediated a number of times over the last hundred of years – and even earlier than that. Computer and video games are a relative newcomer in this string of remediations, distilling the essential elements of the Western even further into archetypal scenes, characters and modes of play. Expanding on our previous works on genres, we study a colorful selection of Western-themed games, 31 in total, with the aim to reveal how a firmly established and codified theme affects gameplay. A well-established theme, such as the Western, manifests itself at very different depths based on the kind of game we are dealing with – at minimum, it acts as an artificial surface that does not affect the gameplay at all. At the other end of the spectrum, the theme affects all the aspects of a game, ranging from its audiovisual presentation to the narrative and the actions available to the player.</div

PETSCII – A Character Set and a Creative Platform

PETSCII is the built-in character set used on 8-bit Commodore computers, such as the PET, C-64 and Plus/4. The character set and the BASIC environment provided an entry point to rudimentary graphic editing for a generation of hobbyists. Over the years PETSCII has been used for a variety of creative purposes: for example games, demos, telecommunications, videos, books and fine art have been created using the graphical symbols. Through the analysis of existing art works and our own hands-on project – a graphics editor – we dig deeper into the specific properties of the character set. In this article we show how the fixed symbols set the frame for what is possible and how, on the other hand, they provide grounds for creative experimentation, display of skill and recognizable styles.</p

PETSCII – A Character Set and a Creative Platform

PETSCII is the built-in character set used on 8-bit Commodore computers, such as the PET, C-64 and Plus/4. The character set and the BASIC environment provided an entry point to rudimentary graphic editing for a generation of hobbyists. Over the years PETSCII has been used for a variety of creative purposes: for example games, demos, telecommunications, videos, books and fine art have been created using the graphical symbols. Through the analysis of existing art works and our own hands-on project – a graphics editor – we dig deeper into the specific properties of the character set. In this article we show how the fixed symbols set the frame for what is possible and how, on the other hand, they provide grounds for creative experimentation, display of skill and recognizable styles

Impact of major life events on breast-cancer-specific mortality : A case fatality study on 8000 breast cancer patients

Background: It has been suggested that long-term activation of the body's stress-response system and subsequent overexposure to stress hormones may be associated with increased morbidity. However, evidence on the impact of major life events on mortality from breast cancer (BC) remains inconclusive. The main aim of this study is to investigate whether major negatively or positively experienced life events before or after diagnosis have an effect on BC-specific mortality in women who have survived with BC for at least 2 years. Methods: We conducted a case fatality study with data on life events from a self-administered survey and data on BC from the Finnish Cancer Registry. Cox models were fitted to estimate BC mortality hazard ratios (MRs) between those who have undergone major life events and those who haven't. Results: None of the pre-diagnostic negative life events had any effect on BC-specific mortality. Regarding post-diagnostic events, the effect was greatest in women with moderate scores of events. As for event-specific scores, increased BC mortality was observed with spouse unemployment, relationship problems, and death of a close friend. By contrast, falling in love and positive developments in hobbies were shown to be associated with lower BC mortality (MRs 0.67, 95% CI: 0.49-0.92 and 0.74, 95% CI: 0.57-0.96, respectively). In an analysis restricted to recently diagnosed cases (2007), also death of a child and of a mother was associated with increased BC mortality. Conclusions: Some major life events regarding close personal relationships may play a role in BC-specific mortality, with certain negative life events increasing BC mortality and positive events decreasing it. The observed favorable associations between positive developments in romantic relationships and hobbies and BC mortality are likely to reflect the importance of social interaction and support. (C) 2017 Elsevier Ltd. All rights reserved.Peer reviewe

Real-world effectiveness of pharmacological treatments of opioid use disorder in a national cohort

Abstract Aim To investigate the real-world effectiveness of pharmacological treatments (buprenorphine, methadone) of opioid use disorder (OUD). Design A nationwide, register-based cohort study. Setting Sweden. Participants All residents aged 16?64 living in Sweden using OUD-medication from July 2005 to December 2016 (n=5757, 71.8% men) were identified from registers of prescriptions, inpatient and specialized outpatient care, causes of death, sickness absence and disability pensions. Measurements Main outcome: hospitalization due to OUD. Secondary outcomes: hospitalization due to any cause; death due to all, natural and external causes. Mortality was analysed with between-individual multivariate-adjusted Cox hazards regression model. Recurrent outcomes, such as hospitalizations, were analysed with within-individual analyses to eliminate selection bias. OUD-medication use vs. non-use was modelled with PRE2DUP (from prescription drug purchases to drug use periods) method. Findings Buprenorphine (Hazard Ratio [HR], 0.73; 95% confidence interval [CI, 0.54?0.97) and methadone (HR, 0.74; 95% CI, 0.59?0.93) use were associated with significantly lower risk of OUD-hospitalization, but not any-cause hospitalizations, compared with the time periods when the same individual did not use OUD-medication. The use of buprenorphine and methadone were both associated with significantly lower risk of all-cause mortality (HR, 0.45; 95% CI, 0.34?0.59, HR, 0.51; 95 CI, 0.41?0.63, respectively), compared with non-use of both medications. Similar results were found for risk of mortality due to external causes (HR, 0.39; 95% CI, 0.27?0.54, HR, 0.40; 95% CI, 0.29?0.53, respectively), but not for mortality due to natural causes. The risk of OUD-hospitalization and all-cause mortality was decreased in all duration categories of studied medications (365 days), except for methadone use less than 30 days. Conclusions The use of buprenorphine and methadone are both associated with a significantly lower risk of hospitalization due to opioid use disorder and death due to all and external causes, when compared with non-use.Peer reviewe

Chemical Characterization of Gas- and Particle-Phase Products from the Ozonolysis of alpha-Pinene in the Presence of Dimethylamine

Amines are recognized as key compounds in new particle formation (NPF) and secondary organic aerosol (SOA) formation. In addition, ozonolysis of a-pinene contributes substantially to the formation of biogenic SOAs in the atmosphere. In the present study, ozonolysis of a-pinene in the presence of dimethylamine (DMA) was investigated in a flow tube reactor. Effects of amines on SOA formation and chemical composition were examined. Enhancement of NPF and SOA formation was observed in the presence of DMA. Chemical characterization of gas and particle-phase products by high-resolution mass spectrometric techniques revealed the formation of nitrogen containing compounds. Reactions between ozonolysis reaction products of a-pinene, such as pinonaldehyde or pinonic acid, and DMA were observed. Possible reaction pathways are suggested for the formation of the reaction products. Some of the compounds identified in the laboratory study were also observed in aerosol samples (PM1) collected at the SMEAR II station (Hyytiala, Finland) suggesting that DMA might affect the ozonolysis of a-pinene in ambient conditions.Peer reviewe