Power line communication in motor cables of variable-speed electric drives − analysis and

Data transmission between an electric motor and a frequency converter is required in variablespeed electric drives because of sensors installed at the motor. Sensor information can be used for various useful applications to improve the system reliability and its properties. Traditionally, the communication medium is implemented by an additional cabling. However, the costs of the traditional method may be an obstacle to the wider application of data transmission between a motor and a frequency converter. In any case, a power cable is always installed between a motor and a frequency converter for power supply, and hence it may be applied as a communication medium for sensor level data. This thesis considers power line communication (PLC) in inverter-fed motor power cables. The motor cable is studied as a communication channel in the frequency band of 100 kHz−30 MHz. The communication channel and noise characteristics are described. All the individual components included in a variable-speed electric drive are presented in detail. A channel model is developed, and it is verified by measurements. A theoretical channel information capacity analysis is carried out to estimate the opportunities of a communication medium. Suitable communication and forward error correction (FEC) methods are suggested. A general method to implement a broadband and Ethernet-based communication medium between a motor and a frequency converter is proposed. A coupling interface is also developed that allows to install the communication device safely to a three-phase inverter-fed motor power cable. Practical tests are carried out, and the results are analyzed. Possible applications for the proposed method are presented. A speed feedback motor control application is verified in detail by simulations and laboratory tests because of restrictions for the delay in the feedback loop caused by PLC. Other possible applications are discussed at a more general level.

Knowledge sharing in virtual communities

The Internet has transformed the scope, boundaries and dynamics of social and economic interactions. It is argued to have broadened the notion of the community from physical, colocated groups towards collectives that are able to transcend time and space, i.e. virtual communities. Even if virtual communities have been on the academic agenda for a couple of decades, there is still surprisingly little research on knowledge sharing within them. In addition, prior research has largely neglected the complex dynamics between Internet-based communication channels and the surrounding communities in which they are embedded. This thesis aims at building a better understanding of knowledge sharing supported by conversational technologies in intra-organisational virtual communities and external virtual communities supporting relationships with customers. The focus is thus on knowledge sharing in types of virtual communities that seem to be of relevance to business organisations. The study consists of two parts. The first part introduces the research topic and discusses the overall results. The second part comprises seven research publications. Qualitative research methods are used throughout the study. The results of the study indicate that investigation of the processes of knowledge sharing in virtual communities requires a socio-technical perspective, combining the individual, social and technological levels, and understanding the interplay between them. It is claimed that collective knowledge in virtual communities creates the enabling structure for knowledge sharing, and forms the invisible structure of the community on the basis of which it operates. It consists of a shared context, social capital and a unique community culture. The Internet does not inevitably erode social interaction: it seems that supporting social relationships by means of communication technology is a matter of quantity rather than quality. In order to provide access to external knowledge and expertise, firms need to open themselves up to an array of Internet-based conversations, and to consider the relevance of virtual communities to their businesses.

Exposure to Tobacco Smoke and Markers of Subclinical Atherosclerosis in Children and Adolescents. The STRIP Study.

Background: Measurement of serum cotinine, a major metabolite of nicotine, provides a valid marker for quantifying exposure to tobacco smoke. Exposure to tobacco smoke causes vascular damage by multiple mechanisms, and it has been acknowledged as a risk factor for atherosclerosis. Multifactorial atherosclerosis begins in childhood, but the relationship between exposure to tobacco smoke and arterial changes related to early atherosclerosis have not been studied in children. Aims: The aim of the present study was to evaluate exposure to tobacco smoke with a biomarker, serum cotinine concentration, and its associations with markers of subclinical atherosclerosis and lipid profile in school-aged children and adolescents. Subjects and Methods: Serum cotinine concentration was measured using a gas chromatographic method annually between the ages 8 and 13 years in 538-625 children participating since infancy in a randomized, prospective atherosclerosis prevention trial STRIP (Special Turku coronary Risk factor Intervention Project). Conventional atherosclerosis risk factors were measured repeatedly. Vascular ultrasound studies were performed among 402 healthy 11-year-old children and among 494 adolescents aged 13 years. Results: According to serum cotinine measurements, a notable number of the school aged children and adolescents were exposed to tobacco smoke, but the exposure levels were only moderate. Exposure to tobacco smoke was associated with decreased endothelial function as measured with flow-mediated dilation of the brachial artery, decreased elasticity of the aorta, and increased carotid and aortic intima-media thickness. Longitudinal exposure to tobacco smoke was also related with increased apolipoprotein B and triglyceride levels in 13-year-old adolescents, whose body mass index and nutrient intakes did not differ. Conclusions: These findings suggest that exposure to tobacco smoke in childhood may play a significant role in the development of early atherosclerosis. Key Words: arterial elasticity, atherosclerosis, children, cotinine, endothelial function, environmental tobacco smoke, intima-media thickness, risk factors, ultrasound

Kuormitustestausvälineen valinta Microsoft Office SharePoint Server 2007 – toteutuksessa

Kuormitustestaus on osa web-sovellusten kehitystä ja käyttöönottoa. Sillä varmistetaan sovellusten toimivuus ennalta määrätyn kuorman alla. Microsoft Office SharePoint Server 2007 (MOSS) on palvelintuote nykyaikaisten web-sovellusten luontiin ja ylläpitoon. Työssä vertaillaan kahta eri uormitustestaustyökalua: SilkPerformer 2008 ja Visual Studio Team System 2008 Test Edition ja valitaan MOSS – web-sovelluksille paremmin sopiva työkalu. Työssä vertaillaan työkaluja niiden ominaisuuksien perusteella sekä suorittamalla kuormitustestausta testausta varten luodulle MOSS – web-sovellukselle. Vaikuttavien tekijöiden perusteella työkaluja arvioidaan ja tämän perusteella saadaan tulos vertailulle. Työn tuloksena Visual Studio Team System 2008 Test Edition sopii paremmin MOSS – web-sovelluksen kuormitustestausvälineeksi. Vertailussa kuitenkin havaittiin, että työkalut ovat melko tasavertaisia, ja käytännön tilanteesta riippuu, kumpi sopii paremmin. Tämä työ auttaa valinnan teossa.

Jazz : Sibelius-Akatemian Jazzstudio

Digitoitu 15. 10 2008.

Rappresentazione di anima e di corpo

Digitoitu 17. 9. 2008.

Ympäristöasioiden hallinnan kehittäminen elintarviketeollisuuden yrityksessä

Ympäristöjärjestelmät auttavat organisaatioiden toiminnan ympäristövaikutuksien hallinnassa. ISO 14001 -standardi antaa yritykselle työkalun ympäristöjärjestelmän rakentamiseen, ylläpitämiseen ja kehittämiseen. Ympäristöjärjestelmälle voidaan hakea ulkopuolisen tarkastajan myöntämä hyväksyntä eli sertifikaatti, jota sidosryhmät voivat vaatia osoitukseksi ympäristöasioiden hoidosta. Sidosryhmien kasvava ympäristökiinnostus lisää yrityksien paineita kehittää ympäristöraportointiaan. Yrityksen yhteiskuntavastuuseen sisältyvien taloudellisen, sosiaalisen ja ympäristövastuun raportointiin kehitetty kansainvälinen GRI-raportointiohjeisto on saavuttanut yleisesti hyväksytyn raportointiviitekehyksen aseman ja sitä voidaan hyödyntää myös pelkän ympäristövastuun raportoinnissa. Tässä diplomityössä tarkastellaan yrityksen ympäristöasioiden hallintaa ja ympäristöraportointia. Tavoitteena on suunnitella ja osittain toteuttaa elintarviketeollisuuden yritykselle ISO 14001 -standardin mukainen ympäristöjärjestelmä. Toisena tavoitteena on suunnitella yrityksen ympäristöraportoinnin aloittamista ja antaa GRI-ohjeiston pohjalta ehdotus asioista, joita yrityksen ympäristöraportti voisi raportoinnin alkuvaiheessa sisältää. Työn lopussa annetaan ehdotus jatkotoimenpiteistä, joilla ympäristöjärjestelmä saadaan sertifiointivalmiiksi ja miten ympäristöraportointiprosessia voidaan edistää.

Sales and Operations Planning Implementation

The master’s thesis focused on implementing a sales and operations planning process. The main objectives were to create planning methods and tools for the implementation. The ultimate goal of the process, beyond this master’s thesis, is to balance the supply of products with customer demand, with optimized profitability. The theoretical part focused on giving a thorough view on the sales and operations planning process. The basis for a monthly planning cycle was identified. Methods, tools, and metrics for demand forecasting and operations planning were also introduced. Based on the theoretical part, a method for forecasting, a forecast spreadsheet, and a forecast accuracy metric were designed. A spreadsheet tool and methods were also designed for the monthly planning of production volumes, capacity, and inventory. The implementation progress was reviewed for two product families for three months. The sales and operations planning process was able to successfully identify a demand peak for the product families. Suggestions for the future of sales and operations planning were also made.