Flash Memory Cells Reliability Parameters Investigation

The present work is a part of the large project with purpose to qualify the Flash memory for automotive application using a standardized test and measurement flow. High memory reliability and data retention are the most critical parameters in this application. The current work covers the functional tests and data retention test. The purpose of the data retention test is to obtain the data retention parameters of the designed memory, i.e. the maximum time of information storage at specified conditions without critical charge leakage. For this purpose the charge leakage from the cells, which results in decrease of cells threshold voltage, was measured after a long-time hightemperature treatment at several temperatures. The amount of lost charge for each temperature was used to calculate the Arrhenius constant and activation energy for the discharge process. With this data, the discharge of the cells at different temperatures during long time can be predicted and the probability of data loss after years can be calculated. The memory chips, investigated in this work, were 0.035 μm CMOS Flash memory testchips, designed for further use in the Systems-on-Chips for automotive electronics.

Managing virtual project teams

The purpose of the Master’s Thesis is to study the best practices to virtual project management from the project manager’ point of view. The best practices are divided according to a five-phase virtual project life cycle model. Each phase include concrete suggestions for actions. Research’s theoretical background is wide because of the broad subject matter. In the theoretical part topics such as virtual working, virtual project management challenges are examined and some concrete actions to tackle these challenges are introduced. Thesis’ approach is constructive, where a known problem is solved piece by piece after creating a pre-understanding of the topic. Existing research work is utilized when creating a model for virtual project team management. The basis of the model comes from various best practices read from literature and from the interviews conducted on experienced virtual project managers in the case organization. As a result the model combines both previous research and the organizations empirical experience. As an output of the thesis a model for virtual project team management is developed, which can be used as a guideline by the virtual project managers in their work. The model includes actions and practices what can be used to overcome the challenges of virtual project management.

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.

Towards Innovative Virtual Learning in Vocational Teacher Education: Narratives as a Form of Meaningful Learning

http://www.eurodl.org/.

Ba in Virtual Communities

Virtual communities – interactive networks in cyberspace seasoned with feelings – are a highly topical research theme. Besides academics, more and more companies ponder upon the nature and implications of the sense of virtual communities. This thesis takes a novel viewpoint on this research and examines virtual communities from virtual ba perspective. Ba is the space – in this case a virtual and a mental one, where knowledge based interaction occurs. The aim of this thesis is to clarify the concept of virtual ba, and the development and appearance of ba in virtual communities. The scientific contribution of this qualitative case study is conceptual clarification and validation of the concept of virtual ba. The empirical part of the thesis examines blogs: Internet-based communication media, using data triangulation (observation, narratives and a thematic interview). The thesis provides insights into the development of virtual ba that has also managerial relevance.

Knowledge Sharing in a Virtual Learning Community

The focus of this Master’s Thesis is on knowledge sharing in a virtual Learning community. The theoretical part of this study aims at presenting the theory of knowledge sharing, competence development and learning in virtual teams. The features of successful learning organizations as well as enablers of effective knowledge sharing in virtual communities are also introduced to the reader in the theoretical framework. The empirical research for this study was realized in a global ICT company, specifically in its Human Resources business unit. The research consisted of two rounds of online questionnaires, which were conducted among all the members of the virtual Learning community. The research aim was to find shared opinions concerning the features of a successful virtual Learning community. The analysis of the data in this study was conducted using a qualitative research methodology. The empirical research showed that the main important features of a successful virtual Learning community are members’ passion towards the community way of working as well as the relevance of the content in the virtual community. In general, it was found that knowledge sharing and competence development are important matters in dynamic organizations as well as virtual communities as method and tool for sharing knowledge and hence increasing both individual and organizational knowledge. This is proved by theoretical and by empirical research in this study.

Study of ligand-based virtual screening tools in computer-aided drug design

Virtual screening is a central technique in drug discovery today. Millions of molecules can be tested in silico with the aim to only select the most promising and test them experimentally. The topic of this thesis is ligand-based virtual screening tools which take existing active molecules as starting point for finding new drug candidates. One goal of this thesis was to build a model that gives the probability that two molecules are biologically similar as function of one or more chemical similarity scores. Another important goal was to evaluate how well different ligand-based virtual screening tools are able to distinguish active molecules from inactives. One more criterion set for the virtual screening tools was their applicability in scaffold-hopping, i.e. finding new active chemotypes. In the first part of the work, a link was defined between the abstract chemical similarity score given by a screening tool and the probability that the two molecules are biologically similar. These results help to decide objectively which virtual screening hits to test experimentally. The work also resulted in a new type of data fusion method when using two or more tools. In the second part, five ligand-based virtual screening tools were evaluated and their performance was found to be generally poor. Three reasons for this were proposed: false negatives in the benchmark sets, active molecules that do not share the binding mode, and activity cliffs. In the third part of the study, a novel visualization and quantification method is presented for evaluation of the scaffold-hopping ability of virtual screening tools.

The relationship between a virtual leader’s communication practices and a virtual team’s performance

A lot of research has been carried out into virtual teams and virtual leadership, yet there is hardly any research available on the communication behaviour of virtual leaders within a real business context. This research assessed the communication practices of virtual leaders and analysed the relationship between these practices and the performance of virtual teams. The objective of this research was to examine the distinctions of virtual teams, to study the leader’s role in a virtual team and its performance, and to examine the leader’s communication practices within virtual teams. The research involves a case study in which interviews have been carried out within an international technology company headquartered in Finland. Qualitative research methods were applied in the research. Based on the results of the study it can be said that there is a strong relationship between a virtual leader’s communication practices and a virtual team member’s job satisfaction. Through their communication practices, activities and message contents, leaders can affect the job satisfaction of virtual team members. In virtual leadership the focus is not in virtual but in leadership. It does not matter if the context is virtual or face-to-face; similar communication practices are good in both cases. As the global economic crisis strongly affected the sales results of the between a leader’s communication practices and a virtual team’s objective performance cannot be made.

Virtual Professional Network as a Value Creator in the Dental Business

The research of virtual professional networks has been enormous but the lack of research in the dental field was obvious. This study focuses on those uses and gratifications, and motives of participants that a virtual pro-fessional network should fulfil. The aim of this study is to understand the factors behind the successful virtual professional network, and motives of participants that support a particular business network’s building up for contributing its further success. In this study the focus is on particular mo-tives, needs and benefits of participants that are significant for the net-work’s further development. The study will explore relevant scientific research and theory that is char-acteristic in networking, and theories of user’s needs and motives. Empiri-cal data was collected from dental professionals by net based question-naire that was sent by e-mail. Data analysis was done by quantitative fac-tor analysis. The findings of this study were obvious that virtual knowledge of implantology is inadequate and knowledge is rather difficult to find in the Internet. Sharing of virtual knowledge, net-learning and communication were seen to improve the quality of impolantological professionalism and also the development of these areas was experienced essential. On the grounds of this study a host of a virtual professional network can focus on those aspects that serve the users at best, can develop professionalism in implantology and can profit in its own business operations.

Virtual Battlespace 2 Panssarikoulun opetuksessa : tapaustutkimus sotilaspedagogiikan näkökulmasta

Tutkielmani tavoitteena oli tutkia tapauksena Bohemia Interactive Simulationsin valmistaman Virtual Battlespace 2 (VBS2) -tietokonepelisimulaattorin käyttöönottoa Panssariprikaatin Panssarikoulun varusmieskoulutuksessa. Tutkimuskysymysten avulla oli tarkoituksena selvittää, mitkä tekijät ja tapahtumat vaikuttivat siihen, että VBS2 otettiin käyttöön, minkälaisin perustein koulutus suunniteltiin ja järjestelmän käyttö varusmieskoulutuksessa käynnistettiin. Lisäksi ajatuksena oli aineiston mahdollistamissa puitteissa tutkia VBS2:n käytöstä tähän mennessä kertyneitä kokemuksia kouluttajien näkökulmasta, tavoitteena tuottaa myös perustietoa tulevaisuuden VBS2-koulutuksen suunnittelua ja toteuttamista varten. Tutkimusmenetelmänä oli tapaustutkimus, jonka aineisto kerättiin toteuttamalla teemahaastatteluita. Tutkimusta varten haastateltiin kahta VBS2-järjestelmää ensimmäisenä varusmieskoulutuksessa käyttänyttä kouluttajaa. Haastatteluaineisto käsiteltiin aineistolähtöisen sisällönanalyysin menetelmin. Tuloksia tarkasteltiin sotilaspedagogiikan näkökulmasta ja suhteessa oppimisympäristöjen sekä oppimisprosessin suunnittelun teorioihin. Tutkielma rakentuu johdannosta, menetelmäluvusta, yhdistetystä teoria- ja tulosluvusta sekä johtopäätös- ja pohdintaluvusta. Tutkimuksen tuloksina ilmeni, että Virtual Battlespace 2:n käyttöönotto Panssarikoulussa oli aktiivisten ja innovatiivisten henkilöiden aikaansaannosta, jossa spontaanin, ennakkoluulottoman ja opetuksen laadun kehittämiseen tähtäävän kokeilun myötä otettiin käyttöön uudenlainen koulutusväline. Samalla saatiin aikaan myönteisiä oppimistuloksia ja kiinnostavia muutoksia yhden joukkoyksikön koulutuskulttuuriin ja totunnaisiin koulutuksen käytäntöihin. VBS2:n käyttöön liittyviä keskeisiä teemoja ovat oppimisprosessin kokonaisvaltainen hallinta, eli VBS2-koulutuksen huolellinen suunnittelu ja integrointi osaksi muuta koulutusta, koulutustapahtumien valmistelujen ja kouluttajien ammattitaidon merkitys, koulutustapahtumien johtamisen paikoin muusta sotilaskoulutuksesta poikkeavat käytännöt sekä VBS2:n aikaansaaman oppimisen ymmärtäminen. Kouluttajien kokemusten perusteella VBS2 on avoin oppimisympäristö, joka ei korvaa mitään olemassa olevista koulutusmuodoista, mutta täydentää niitä tehokkaasti tarjoten uudenlaisia ulottuvuuksia sotilaskoulutukseen. Sen avulla voidaan tehokkaasti kehittää erityisesti sotilaan henkistä ja sosiaalista toimintakykyä sekä siirtää koulutuksen painopistettä soveltaviin maastoharjoituksiin. Tutkielma avaa näkökulmia VBS2:n ja muiden virtuaalisten oppimisympäristöjen pedagogiselle pohtimiselle ja tuleville aiheeseen syventyville tutkimuksille. Lisäksi se herättää keskustelua varusmieskoulutuksemme parhaista käytänteistä ja kehitystrendeistä.

Memory studies - kohti tutkimusalueen vakiintumista

Teemanumero 2/2011: Media ja menneisyys.