Power-line-communication-based data transmission concept for an LVDC electricity distribution network – Analysis and implementation

Communications play a key role in modern smart grids. New functionalities that make the grids ‘smart’ require the communication network to function properly. Data transmission between intelligent electric devices (IEDs) in the rectifier and the customer-end inverters (CEIs) used for power conversion is also required in the smart grid concept of the low-voltage direct current (LVDC) distribution network. Smart grid applications, such as smart metering, demand side management (DSM), and grid protection applied with communications are all installed in the LVDC system. Thus, besides remote connection to the databases of the grid operators, a local communication network in the LVDC network is needed. One solution applied to implement the communication medium in power distribution grids is power line communication (PLC). There are power cables in the distribution grids, and hence, they may be applied as a communication channel for the distribution-level data. This doctoral thesis proposes an IP-based high-frequency (HF) band PLC data transmission concept for the LVDC network. A general method to implement the Ethernet-based PLC concept between the public distribution rectifier and the customerend inverters in the LVDC grid is introduced. Low-voltage cables are studied as the communication channel in the frequency band of 100 kHz–30 MHz. The communication channel characteristics and the noise in the channel are described. All individual components in the channel are presented in detail, and a channel model, comprising models for each channel component is developed and verified by measurements. The channel noise is also studied by measurements. Theoretical signalto- noise ratio (SNR) and channel capacity analyses and practical data transmission tests are carried out to evaluate the applicability of the PLC concept against the requirements set by the smart grid applications in the LVDC system. The main results concerning the applicability of the PLC concept and its limitations are presented, and suggestion for future research proposed.

Junan matkustajainformaatiojärjestelmän ohjaaminen

Matkustajat pitävät junissa annettavaa informaatiota entistä tärkeämpänä. Tähän haasteeseen pyritään vastaamaan rutiinikuulutusten, kuten asemille tulokuulutusten, automatisoinnilla. Kuulutukset soitetaan ääneen ja esitetään tekstinä näytöillä. Tällöin annettava informaatio on selkeää ja tasalaatuista myös vieraalla kielellä. Junan tiedot, kuten määränpää ja vaunun myyntinumero, esitetään junan ulkoseinällä ovien vierellä junaan nousevia matkustajia varten. Tässä diplomityössä luodaan yleiskatsaus junaväylään liittyviin standardeihin, TCN-standardiin ja UIC-556-määrelehteen. Yleiskatsauksen lisäksi käsitellään tarkemmin matkustajainformaatiojärjestelmään liittyvät osat. Tutustumme myös UIC-176-määrelehteen, joka käsittelee matkustajainformaatiojärjestelmän näyttöjä. Luomme yleiskatsauksen EKE-Elektroniikka Oy:n kehittämään modulaariseen junanhallintajärjestelmään. Työssä suunnitellaan asiakkaan ja standardien vaatimusten pohjalta matkustajainformaatiojärjestelmä, joka on integroitu junanhallintajärjestelmään. Tekstitiedon välittämiseen vaunusta toiseen käytetään WTB-junaväylää. Siinä kommunikoidaan UIC-556-määrelehden mukaisesti, joka mahdollistaa eurooppalaisen yhteensopivuuden. Työn tuloksena on määritelty järjestelmän fyysinen rakenne, ohjelmistorakenne, vaadittavat tietokannat, tiedon syöttäminen järjestelmälle ja junaväylässä käytettävät telegrammit. Erityishaasteena on ratkaistu tilanne, jossa juna jakautuu matkan varrella useampaan suuntaan.

On Fault Tolerance Methods for Networks-on-Chip

Technology scaling has proceeded into dimensions in which the reliability of manufactured devices is becoming endangered. The reliability decrease is a consequence of physical limitations, relative increase of variations, and decreasing noise margins, among others. A promising solution for bringing the reliability of circuits back to a desired level is the use of design methods which introduce tolerance against possible faults in an integrated circuit. This thesis studies and presents fault tolerance methods for network-onchip (NoC) which is a design paradigm targeted for very large systems-onchip. In a NoC resources, such as processors and memories, are connected to a communication network; comparable to the Internet. Fault tolerance in such a system can be achieved at many abstraction levels. The thesis studies the origin of faults in modern technologies and explains the classification to transient, intermittent and permanent faults. A survey of fault tolerance methods is presented to demonstrate the diversity of available methods. Networks-on-chip are approached by exploring their main design choices: the selection of a topology, routing protocol, and flow control method. Fault tolerance methods for NoCs are studied at different layers of the OSI reference model. The data link layer provides a reliable communication link over a physical channel. Error control coding is an efficient fault tolerance method especially against transient faults at this abstraction level. Error control coding methods suitable for on-chip communication are studied and their implementations presented. Error control coding loses its effectiveness in the presence of intermittent and permanent faults. Therefore, other solutions against them are presented. The introduction of spare wires and split transmissions are shown to provide good tolerance against intermittent and permanent errors and their combination to error control coding is illustrated. At the network layer positioned above the data link layer, fault tolerance can be achieved with the design of fault tolerant network topologies and routing algorithms. Both of these approaches are presented in the thesis together with realizations in the both categories. The thesis concludes that an optimal fault tolerance solution contains carefully co-designed elements from different abstraction levels

Mobile Teleoperation of a Mobile Robot

This thesis describes the design and implementation of a graphical application on a mobile device to teleoperate a mobile robot. The department of information technology in Lappeenranta University conducts research in robotics, and the main motivation was to extend the available teleoperation applications for mobile devices. The challenge was to port existing robot software library onto an embedded device platform, then develop a suitable user interface application that provides sufficient functionality to perform teleoperation tasks over a wireless communication network. This thesis involved investigating previous teleoperation applications and conducted similar experiments to test and evaluate the designed application for functional activity and measure performance on a mobile device which have been identified and achieved. The implemented solution offered good results for navigation purposes particularly for teleoperating a visible robot and suggests solutions for exploration when no environment map for the operator is present.

Työnantajan oikeus lukea työntekijän sähköposteja

Sähköpostin käyttö suomalaisilla työpaikoilla on kasvanut merkittävästi 2000 -luvun alusta lähtien. Tänä päivänä suuri osa työntekijöistä käyttää työpaikoillaan sähköpostia päivittäin. Tutkimuksen tavoitteena on tutkia työnantajan oikeutta lukea työntekijän sähköposteja. Edellisen lisäksi huomio kiinnittyi työntekijän yksityisyyden suojaan sekä työnantajan oikeuksiin ja velvollisuuksiin. Tutkimukseni on toteutettu kvalitatiivisena tutkimuksena. Tutkimusaineistoon valittiin kaikki tutkimusaihetta koskevat kirjoitukset. Aineisto kerättiin pääasiallisesti suomalaisista lakiteksteistä sekä tutkielmani empiirinen osio koostui neljästä suomalaisesta oikeustapauksesta. Tutkimuksen perusteella voidaan todeta, että Suomessa työnantajat osaavat kunnioittaa työntekijän yksityisyyttä ja sähköpostin käytöstä työpaikoilla ei ole usein syntynyt ongelmia.

Power Electronic Converters in Low-Voltage Direct Current Distribution – Analysis and Implementation

Over the recent years, smart grids have received great public attention. Many proposed functionalities rely on power electronics, which play a key role in the smart grid, together with the communication network. However, “smartness” is not the driver that alone motivates the research towards distribution networks based on power electronics; the network vulnerability to natural hazards has resulted in tightening requirements for the supply security, set both by electricity end-users and authorities. Because of the favorable price development and advancements in the field, direct current (DC) distribution has become an attractive alternative for distribution networks. In this doctoral dissertation, power electronic converters for a low-voltage DC (LVDC) distribution system are investigated. These include the rectifier located at the beginning of the LVDC network and the customer-end inverter (CEI) on the customer premises. Rectifier topologies are introduced, and according to the LVDC system requirements, topologies are chosen for the analysis. Similarly, suitable CEI topologies are addressed and selected for study. Application of power electronics into electricity distribution poses some new challenges. Because the electricity end-user is supplied with the CEI, it is responsible for the end-user voltage quality, but it also has to be able to supply adequate current in all operating conditions, including a short-circuit, to ensure the electrical safety. Supplying short-circuit current with power electronics requires additional measures, and therefore, the short-circuit behavior is described and methods to overcome the high-current supply to the fault are proposed. Power electronic converters also produce common-mode (CM) and radio-frequency (RF) electromagnetic interferences (EMI), which are not present in AC distribution. Hence, their magnitudes are investigated. To enable comprehensive research on the LVDC distribution field, a research site was built into a public low-voltage distribution network. The implementation was a joint task by the LVDC research team of Lappeenranta University of Technology and a power company Suur-Savon S¨ahk¨o Oy. Now, the measurements could be conducted in an actual environment. This is important especially for the EMI studies. The main results of the work concern the short-circuit operation of the CEI and the EMI issues. The applicability of the power electronic converters to electricity distribution is demonstrated, and suggestions for future research are proposed.

From network pictures to network insight in solution business – the role of internal communication

Operating in business-to-business markets requires an in-depth understanding on business networks. Actions and reactions made to compete in markets are fundamentally based on managers‘ subjective perceptions of the network. However, an amalgamation of these individual perceptions, termed a network picture, to a common company level shared understanding on that network, known as network insight, is found to be a substantial challenge for companies. A company‘s capability to enhance common network insight is even argued to lead competitive advantage. Especially companies with value creating logics that require wide comprehension of and collaborating in networks, such as solution business, are necessitated to develop advanced network insight. According to the extant literature, dispersed pieces of atomized network pictures can be unified to a common network insight through a process of amalgamation that comprises barriers/drivers of multilateral exchange, manifold rationality, and recursive time. However, the extant body of literature appears to lack an understanding on the role of internal communication in the development of network insight. Nonetheless, the extant understanding on the amalgamation process indicates that internal communication plays a substantial role in the development of company level network insight. The purpose of the present thesis is to enhance understanding on internal communication in the amalgamation of network pictures to develop network insight in the solution business setting, which was chosen to represent business-to-business value creating logic that emphasizes the capability to understand and utilize networks. Thus, in solution business the role of succeeding in the amalgamation process is expected to emphasize. The study combines qualitative and quantitative research by means of various analytical methods including multiple case analysis, simulation, and social network analysis. Approaching the nascent research topic with differing perspectives and means provides a broader insight on the phenomenon. The study provides empirical evidence from Finnish business-to-business companies which operate globally. The empirical data comprise interviews (n=28) with managers of three case companies. In addition the data includes a questionnaire (n=23) collected mainly for the purpose of social network analysis. In addition, the thesis includes a simulation study more specifically achieved by means of agent based modeling. The findings of the thesis shed light on the role of internal communication in the amalgamation process, contributing to the emergent discussion of network insights and thus to the industrial marketing research. In addition, the thesis increases understanding on internal communication in the change process to solution business, a supplier‘s internal communication in its matrix organization structure during a project sales process, key barriers and drivers that influence internal communication in project sales networks, perceived power within industrial project sales, and the revisioning of network pictures. According to the findings, internal communication is found to play a substantial role in the amalgamation process. First, it is suggested that internal communication is a base of multilateral exchange. Second, it is suggested that internal communication intensifies and maintains manifold rationality. Third, internal communication is needed to explicate the usually differing time perspectives of others and thus it is suggested that internal communication has role as the explicator of recursive time. Furthermore, the role of an efficient amalgamation process is found to be emphasized in solutions business as it requires a more advanced network insight for cross-functional collaboration. Finally, the thesis offers several managerial implications for industrial suppliers to enhance the amalgamation process when operating in solution business.

Value added logistics in supply and demand chains. Smile. Part 1. eBusiness between global company and itslocal sme supplier network

VALOSADE (Value Added Logistics in Supply and Demand Chains) is the research project of Anita Lukka's VALORE (Value Added Logistics Research) research team inLappeenranta University of Technology. VALOSADE is included in ELO (Ebusiness logistics) technology program of Tekes (Finnish Technology Agency). SMILE (SME-sector, Internet applications and Logistical Efficiency) is one of four subprojects of VALOSADE. SMILE research focuses on case network that is composed of small and medium sized mechanical maintenance service providers and global wood processing customers. Basic principle of SMILE study is communication and ebusiness insupply and demand network. This first phase of research concentrates on creating backgrounds for SMILE study and for ebusiness solutions of maintenance case network. The focus is on general trends of ebusiness in supply chains and networksof different industries; total ebusiness system architecture of company networks; ebusiness strategy of company network; information value chain; different factors, which influence on ebusiness solution of company network; and the correlation between ebusiness and competitive advantage. Literature, interviews and benchmarking were used as research methods in this qualitative case study. Networks and end-to-end supply chains are the organizational structures, which can add value for end customer. Information is one of the key factors in these decentralized structures. Because of decentralization of business, information is produced and used in different companies and in different information systems. Information refinement services are needed to manage information flows in company networksbetween different systems. Furthermore, some new solutions like network information systems are utilised in optimising network performance and in standardizingnetwork common processes. Some cases have however indicated, that utilization of ebusiness in decentralized business model is not always a necessity, but value-add of ICT must be defined case-specifically. In the theory part of report, different ebusiness and architecture models are introduced. These models are compared to empirical case data in research results. The biggest difference between theory and empirical data is that models are mainly developed for large-scale companies - not for SMEs. This is due to that implemented network ebusiness solutions are mainly large company centered. Genuine SME network centred ebusiness models are quite rare, and the study in that area has been few in number. Business relationships between customer and their SME suppliers are nowadays concentrated more on collaborative tactical and strategic initiatives besides transaction based operational initiatives. However, ebusiness systems are further mainly based on exchange of operational transactional data. Collaborative ebusiness solutions are in planning or pilot phase in most case companies. Furthermore, many ebusiness solutions are nowadays between two participants, but network and end-to-end supply chain transparency and information systems are quite rare. Transaction volumes, data formats, the types of exchanged information, information criticality,type and duration of business relationship, internal information systems of partners, processes and operation models (e.g. different ordering models) differ among network companies, and furthermore companies are at different stages on networking and ebusiness readiness. Because of former factors, different customer-supplier combinations in network must utilise totally different ebusiness architectures, technologies, systems and standards.

Value added logistics in supply and demand chain. Smile. Part 2. eBusiness in a service business. Case: A maintenance and operations network in forest industry

VVALOSADE is a research project of professor Anita Lukka's VALORE research team in the Lappeenranta University of Technology. The VALOSADE includes the ELO technology program of Tekes. SMILE is one of four subprojects of the VALOSADE. The SMILE study focuses on the case of the company network that is composed of small and micro-sized mechanical maintenance service providers and forest industry as large-scale customers. The basic principle of the SMILE study is the communication and ebusiness in supply and demand networks. The aim of the study is to develop ebusiness strategy, ebusiness model and e-processes among the SME local service providers, and onthe other hand, between the local service provider network and the forest industry customers in a maintenance and operations service business. A literature review, interviews and benchmarking are used as research methods in this qualitative case study. The first SMILE report, 'Ebusiness between Global Company and Its Local SME Supplier Network', concentrated on creating background for the SMILE study by studying general trends of ebusiness in supply chains and networks of different industries. This second phase of the study concentrates on case network background, such as business relationships, information systems and business objectives; core processes in maintenance and operations service network; development needs in communication among the network participants; and ICT solutions to respond needs in changing environment. In the theory part of the report, different ebusiness models and frameworks are introduced. Those models and frameworks are compared to empirical case data. From that analysis of the empirical data, therecommendations for the development of the network information system are derived. In process industry such as the forest industry, it is crucial to achieve a high level of operational efficiency and reliability, which sets up great requirements for maintenance and operations. Therefore, partnerships or strategic alliances are needed between the network participants. In partnerships and alliances, deep communication is important, and therefore the information systems in the network also are critical. Communication, coordination and collaboration will increase in the case network in the future, because network resources must be optimised to improve competitive capability of the forest industry customers and theefficiency of their service providers. At present, ebusiness systems are not usual in this maintenance network. A network information system among the forest industry customers and their local service providers actually is the only genuinenetwork information system in this total network. However, the utilisation of that system has been quite insignificant. The current system does not add value enough either to the customers or to the local service providers. At present, thenetwork information system is the infomediary that share static information forthe network partners. The network information system should be the transaction intermediary, which integrates internal processes of the network companies; the network information system, which provides common standardised processes for thelocal service providers; and the infomediary, which share static and dynamic information on right time, on right partner, on right costs, on right format and on right quality. This study provides recommendations how to develop this system in the future to add value to the network companies. Ebusiness scenarios, vision, objectives, strategies, application architecture, ebusiness model, core processes and development strategy must be considered when the network information system will be developed in the next development step. The core processes in the case network are demand/capacity management, customer/supplier relationship management, service delivery management, knowledge management and cash flow management. Most benefits from ebusiness solutions come from the electrifying of operational level processes, such as service delivery management and cash flow management.

Transparent Network Interfaces to Mobile Peer-to-Peer Environment

The fact that most of new Personal Data Assistant (PDA) devices and smartphones have the ability to communicate via different wireless technologies has made several new applications possible. While traditional network model is based on the idea of static hosts, mobile devices can create decentralized, self-organizing ad-hoc networks and act as peers in the network. This kind of adapting network is suitable for mobile devices which can freely join and leave the networks. Because several different wireless communication technologies are involved, flexible changing of the networking technology must be handled in order to enable seamless communication between these networks. This thesis presents a transparent network interface to mobile Peer-to-Peer environment which is named as Virtual PeerHood. Different wireless technologies and aspects of providing a seamless connectivity between these technologies are explored. The result is a middleware platform for mobile Peer-to-Peer environment, capable of handling several networking technologies.

Radio Resource Management across UMTS Radio Network Subsystems

UMTS (Universal Mobile Telecommunication System), esimerkkinä kolmannen sukupolven matkapuhelinjärjestelmästä pyrkii toistamaan GSM:n (Global System for Mobile Communications) menestyksen. UMTS:n kaupallinen toiminta on parhaillaan alkamassa ja ensimmäinen kaupallinen verkko on jo aloittanut toimintansa Japanissa. Tämä diplomityö antaa yleiskuvan UMTS:stä keskittyen radioverkkojärjestelmän (UMTS Terrestrial Radio Access Network,UTRAN) radioresurssien hallintaan (Radio Resource Management, RRM). Työssä kuvataan radiorajapintojen toimintaa, mutta diplomityön pääaiheena on kuitenkin radioresurssien hallinta UMTS radioaliverkkojärjestelmien ylitse. Radioresurssien hallinta pitää sisällään joukon proseduureja, jotka vaikuttavat koko UTRAN:in rakenteen lävitse. On hyvin tärkeää saavuttaa oikea toiminnallisuus hajautettujen radioresurssien hallintaan jotta voitaisiin saavuttaa paras yhteyden laatu loppukäyttäjälle. Työssä käydään yksityiskohtaisesti lävitse radioresurssien hallinnan perusperiaatteet ja joukko proseduureja. RNSAP (Radio Network Subsystem Application Part) protokollaa tarkastellaan työssä esimerkkinä protokollasta joka osallistuu radioresurssien hallintaprosessiin.

Sisäinen tulosraportointi tietojohtamisen näkökulmasta. Case: Elcoteq Network Oyj

Tutkielman tarkoituksena oli tutkia, mitkä tekijät vaikuttavat sisäisen laskennan tulostiedon oikeellisuuteen ja miten tietojohtamisen keinoin voidaan taata yhteensopivuus ulkoisen ja sisäisen laskentatiedon välillä. Tekijöiden tunnistamisen ja huomioonottamisen kautta voidaan kehittää organisaation tietämystä ja suorituskykyä. Tutkimus oli empiirinen ja kuvaileva tapaustutkimus. Kvalitatiivista aineistoa kerättiin pääasiassa kyselylomakkeen, havainto -ja dokumenttiaineiston avulla. Aineisto analysoitiin teemoittelun avulla. Laskentaorganisaatioissa havaittiin mekaanisen ja orgaanisen tietopääomaympäristön piirteitä, jotka asettavat tiedon välitykselle,vuorovaikutukselle ja tietämyksen kehittymiselle omat rajoitteensa. Laskentaorganisaatioiden toimintaa ohjasivat mekaaniselle ympäristölle tyypilliset vastuu - ja raportointisuhteet, aikataulut ja raportointikäytännöt. Raportointijärjestelmään tarvittaisiin lisäkoulutusta, tiedon vertailtavuuteen ja tiedon oikeellisuuden takaamiseen lisää työvälineitä. Tiedon välittämistä ja kommunikointia pitäisi tehostaa aktiivisemmalla sähköisellä viestinnällä, mutta myös monipuolisemmalla viestintäkanavien käytöllä. Laskentaorganisaatioiden toimintaympäristössä havaittiin orgaanisen tietopääomaympäristön piirteitä, mikä edellyttäisi dialogia tukevien teknologioiden ja toimintatapojen tehokkaampaa käyttöä. Haasteena on maantieteellisen etäisyyden aiheuttamat rajoitteet sekä toiminnan mekaaninen luonne. Uutta konseptia käyttöönotettaessa keskustelut ja vuorovaikutus tukivat mallin kehittämistä ja käytännön sisäistämistä osaksi organisaation tietämystä. Viestintäkanavien käytön tehostamisella voitaisiin edesauttaa tiedon välittymistä. Tietämyksen ja suorituskyvyn kehittäminen laskentaorganisaatioissa edellyttää kuitenkin vuorovaikutteisuuden ja dialogin tukemista.

Performance Management of a Next Generation Network

Today's communication networks consist of numerous interdependent network components. To manage these networks and to ensure their reliable and efficient operation to meet the increasing customer usability demands, extensive network management tools are required from the service provider. The goal of this study was to adapt the Next Generation Network (NGN) providing VoIP services within a performance oriented network management system. This study focuses only on NGN network and the project was implemented as an assignment of the Network Operations Center of Elisa Corporation. The theoretical part of this study introduces the network environment of the Elisa NGN platform: its components and used signalling protocols as well as other exploitable communication protocols. In addition, the Simple Network Management Protocol (SNMP) is closely examined since it is commonly used as the basis of IP (Internet Protocol) network management. Also some primary applications enabled by the NGN technology are introduced. The empirical part of this study contains a short overview of the implemented network performance management system and its properties. The most crucial monitored MIB modules, SNMP parameters and implemented performance measurements are described. The trap topology and the role of the traps for management of the NGN platform are considered and finally, the conclusion based on the several disquisitions is made supported with suggestions for future improvements.

Customer-Related Internal Communication in a Global Matrix Organization

The objective of the thesis was to explore the nature and characteristics of customer-related internal communication in a global industrial matrix organization during a specific customer relationship, and how it could be improved. The theoretical part of the study views the field of the concepts of intra-organizational information and knowledge sharing. The theoretical part also views the internal communications influences to customer relationships, its problematic, and the suggestions to improve internal communication in literature. The empirical part of the study was conducted with the Content Analysis and the Social Network Analysis as research methods. The data was collected by interviews and a questionnaire. Internal communication was observed first generally within the organization from the point of view of a certain business, and secondly, during a specific customer relationship at personal level and at departmental level. The results of the study describe the nature and characteristics of internal communication in the organization. The results give 13 suggestions for improving internal communication in the organization. Although the study has been done in one specific organization, it also offers insights for other organizations as well as managers to improve their internal communication.

A Communication Middleware Quality Enhancement with Qt Framework

In this thesis, a Peer-to-Peer communication middleware for mobile environment is developed using the Qt framework and the Qt Mobility extension. The Peer-to-Peer middleware – called as PeerHood – is for service sharing in network neighborhood. In addition, the PeerHood enables service connectivity and device monitoring functionalities. The concept of the PeerHood is already available in native C++ implementation on Linux platform using services from the platform. In this work, the PeerHood concept is remade to be based on use of the Qt framework. The objective of the new solution is to increase PeerHood quality with using functionalities from the Qt framework and the Qt Mobility extension. Furthermore, by using the Qt framework, the PeerHood middleware can be implemented to be portable cross-platform middleware. The quality of the new PeerHood implementation is evaluated with defined quality factors and compared with the existing PeerHood. Reliability, CPU usage, memory usage and static code analysis metrics are used in evaluation. The new PeerHood is shown to be more reliable and flexible that the existing one.