Mobile Protocol Stack Simulator

Nykypäivän maailma tukeutuu verkkoihin. Tietokoneverkot ja langattomat puhelimet ovat jo varsin tavallisia suurelle joukolle ihmisiä. Uusi verkkotyyppi on ilmestynyt edelleen helpottamaan ihmisten verkottunutta elämää. Ad hoc –verkot mahdollistavat joustavan verkonmuodostuksen langattomien päätelaitteiden välille ilman olemassa olevaa infrastruktuuria. Diplomityö esittelee uuden simulaatiotyökalun langattomien ad hoc –verkkojen simulointiin protokollatasolla. Se esittelee myös kyseisten verkkojen taustalla olevat periaatteet ja teoriat. Lähemmin tutkitaan OSI-mallin linkkikerroksen kaistanjakoprotokollia ad hoc –verkoissa sekä vastaavan toteutusta simulaattorissa. Lisäksi esitellään joukko simulaatioajoja esimerkiksi simulaattorin toiminnasta ja mahdollisista käyttökohteista.

Business models enhancing the diffusion of mobile Internet in emerging markets

Tämän tutkimuksen päätavoitteena oli selvittää, millaiset liiketoimintamallit soveltuvat mobiilin internet-liiketoiminnan harjoittamiseen kehittyvillä markkinoilla. Tavoitteena oli myös selvittää tekijöitä, jotka vaikuttavat mobiilin internetin diffuusioon. Tutkimus tehtiin käyttäen sekä kvantitatiivista että kvalitatiivista tutkimusmenetelmää. Klusterianalyysin avulla 40 Euroopan maasta muodostettiin sisäisesti homogeenisiä maaklustereita. Näiden klustereiden avulla oli mahdollista suunnitella erityyppisille markkinoille soveltuvat liiketoimintamallit. Haastatteluissa selvitettiin asiantuntijoiden näkemyksiä tekijöistä, jotka vaikuttavat mobiilin internetin diffuusioon kehittyvillä markkinoilla. Tutkimuksessa saatiin selville, että tärkeimmät liiketoimintamallin elementit kehittyvillä markkinoilla ovat hinnoittelu, arvotarjooma ja arvoverkko. Puutteellisen kiinteän verkon todettiin olevan yksi tärkeimmistä mobiilin internetin diffuusiota edistävistä tekijöistä kehittyvillä markkinoilla.

Russian mobile telecommunications market: players and trends

Objective of this work was to clarify the competitive situation of Russian mobile telecommunications market: who are the main players, are there many regional operators, what is the possibility of new entrants and how intensive is the competition. In the beginning the history of Russian mobile telecommunications sector is described. In the next chapter environmental factors of the market are examined with the help of PESTEL analysis. After that, players of the market are introduced to ease the following of next chapters. The main theory for this work was industry analysis of five competitive forces by Michael Porter, which is presented before the theory related industry analysis of Russian mobile telecommunications industry. Research for the industry analysis is mainly based on up-to-date articles describing Russian market. As a result of the industry analysis, competitive situation of Russian mobile telecommunications industry and the future prospects are described with the help of factors coming from the PESTEL-analysis. Finally development and future prospects for Russian 3G are reported. As a result of this work, it can be said that Russian mobile telecommunications market is not likely to maintain the growth of previous years, because the market is near saturation. According to passive SIM-cards it has already received saturated. The saturation will also make the market share game between operators more volatile. The market is dominated by three national operators that covered 88% of the income in the first half of 2007. In addition to these three, there are also several regional operators. Structure of the market is likely to consolidate.

Optimizing Mobile Java Location-Based Services in Symbian OS

This thesis evaluates methods for obtaining high performance in applications running on the mobile Java platform. Based on the evaluated methods, an optimization was done to a Java extension API running on top the Symbian operating system. The API provides location-based services for mobile Java applications. As a part of this thesis, the JNI implementation in Symbian OS was also benchmarked. A benchmarking tool was implemented in the analysis phase in order to implement extensive performance test set. Based on the benchmark results, it was noted that the landmarks implementation of the API was performing very slowly with large amounts of data. The existing implementation proved to be very inconvenient for optimization because the early implementers did not take performance and design issues into consideration. A completely new architecture was implemented for the API in order to provide scalable landmark initialization and data extraction by using lazy initialization methods. Additionally, runtime memory consumption was also an important part of the optimization. The improvement proved to be very efficient based on the measurements after the optimization. Most of the common API use cases performed extremely well compared to the old implementation. Performance optimization is an important quality attribute of any piece of software especially in embedded mobile devices. Typically, projects get into trouble with performance because there are no clear performance targets and knowledge how to achieve them. Well-known guidelines and performance models help to achieve good overall performance in Java applications and programming interfaces.

Means and challenges in international operations for a Finnish mobile application provider

Master’s Thesis concentrates to means and challenges in international operations for a Finnish mobile application provider Small Planet Oy during its various company stages from founding till maturing and during macro economical phases between year 1998 and 2008. Small Planet has just celebrated its 10 year anniversary and is therefore quite an extraordinary company which has survived all the highs and lows during past ten years and which has operated in the market as long as the whole mobile application industry has existed. Master’s Thesis describes possibilities for a company’s internationalization with different entry modes like exporting, licensing, investment entry and co-operative operations which are suitable for a mobile application provider. Unsuitable entry modes like franchising or contract manufacturing are not explained. The goal has been to analyze Small Planet’s international operations and to make conclusions from the practical experiences. Analysis and conclusions shall help Small Planet in its international operations in the future and should give insight to other mobile application companies and their managers who are in the situation of planning their own international operations. Results show that the best ways for Small Planet to internationalize its operations has been the co-operation with a big domestic client and the co-operation with Finnish operator infrastructure providers which have complementary products with Small Planet. Through these co-operations Small Planet has got lot of new international clients. Same time financial risks and investment need for international operations have been low. Co-operative international sales can be the most efficient international entry mode for a mobile application provider.

Handover aspects in Unlicensed Mobile Access Technology

Fixed Mobile Convergence is the recent buzz in the field of telecommunication technology. Unlicensed Mobile Access (UMA) technology is a realistic implementation of Fixed Mobile Convergence. UMA involves communication between different types of networks. Handover is a very important issue in UMA. The study is an analysis of theoretical handover mechanism and practical test results. It includes a new proposal for handover performance test in UMA. It also provides an overview of basic handover operation on different scenarios in UMA. The practical test involves an experiment on handover performance test using network analyzers. The new proposal provides a different approach for an experimental setting on handover performance test without using network analyzers. The approach is not be implemented because of some technical problem in a network equipment in UMA. The analysis of the test results reveals that time of handover between UMA and Global System for Mobile Communication (GSM) network is similar to time of handover between inter base station controller (BSC) handover in GSM networks. The new approach is simple and provides measurement at the end point communicating entities. The study gives a general understanding of handover operation, an analysis of handover performance in UMA and specifically provides a new approach useful for further study of handover in different real world environments and scenarios.

Coolant Flow and Heat Transfer in Pebble-Bed Reactor Core

This thesis gathers knowledge about ongoing high-temperature reactor projects around the world. Methods for calculating coolant flow and heat transfer inside a pebble-bed reactor core are also developed. The thesis begins with the introduction of high-temperature reactors including the current state of the technology. Process heat applications that could use the heat from a high-temperature reactor are also introduced. A suitable reactor design with data available in literature is selected for the calculation part of the thesis. Commercial computational fluid dynamics software Fluent is used for the calculations. The pebble-bed is approximated as a packed-bed, which causes sink terms to the momentum equations of the gas flowing through it. A position dependent value is used for the packing fraction. Two different models are used to calculate heat transfer. First a local thermal equilibrium is assumed between the gas and solid phases and a single energy equation is used. In the second approach, separate energy equations are used for the phases. Information about steady state flow behavior, pressure loss, and temperature distribution in the core is obtained as results of the calculations. The effect of inlet mass flow rate to pressure loss is also investigated. Data found in literature and the results correspond each other quite well, considered the amount of simplifications in the calculations. The models developed in this thesis can be used to solve coolant flow and heat transfer in a pebble-bed reactor, although additional development and model validation is needed for better accuracy and reliability.

Adaptive optimization schemes for mobile VoIP applications Battery life and call quality aspects

In this thesis programmatic, application-layer means for better energy-efficiency in the VoIP application domain are studied. The work presented concentrates on optimizations which are suitable for VoIP-implementations utilizing SIP and IEEE 802.11 technologies. Energy-saving optimizations can have an impact on perceived call quality, and thus energy-saving means are studied together with those factors affecting perceived call quality. In this thesis a general view on a topic is given. Based on theory, adaptive optimization schemes for dynamic controlling of application's operation are proposed. A runtime quality model, capable of being integrated into optimization schemes, is developed for VoIP call quality estimation. Based on proposed optimization schemes, some power consumption measurements are done to find out achievable advantages. Measurement results show that a reduction in power consumption is possible to achieve with the help of adaptive optimization schemes.

Context exchange between devices in mobile environment

Context awareness is emerging on mobile devices. Context awareness can be used to improve usability of a mobile device. Context awareness is particularly important on mobile devices due the limitations they have. At first in this work, a literature review on context awareness and mobile environment is made. For aiding context awareness there exist an implementation of a Context Framework for Symbian S60 devices. It provides a possibility for exchanging the contexts inside the device between the client applications of the local Context Framework. The main contribution of this thesis is to design and implement an enhancement to the S60 Context Framework for providing possibility to exchange context over device boundaries. Using the implemented Context Exchange System, the context exchange is neither depending on the type of the context nor the type of the client. In addition, the clients and the contexts can reside on any interconnected device. The usage of the system is independent of the programming language since in addition to using only Symbian C++ function interfaces it can also be utilized using XML scripts. The Meeting Sniffer application, which uses the Context Exchange System, was also developed in this work. Using this application, it is possible to recognize a meeting situation and suggest device profile change to a user.

Comovement of stock price risk in strategic alliance — Case: mobile internet

The focus of this study has been comovement of stock price risk level between two companies as they form strategic alliance. Thus the main reason has been to shed more light to possible increased risk level that the stockholder confronts when a company he owns forms a strategic alliance with another company. This study has centralized to interfirm cooperation between mobile and internet companies, which have furthered the development of mobile internet. The study has been divided into theoretical and empirical part. In theoretical part the main concepts riskiness of a stock (volatility), comovement and strategic alliance have been run through. In empirical part seven strategic alliances formed by mobile internet companies have been examined. Based on this, strategic alliance seems to increase comovement of stock price risk in some degree. This comovement seems to be stronger when core businesses or operating environments of cooperating companies differ more from each other.

Social Networking on Mobile Environment on top of PeerHood

Social networking and social networking sites have gained popularity among internet users during the past few years. Social networks fulfill the need of users to stay connected to friends and other people interested in the same issues. Combining social networks to the mobile environment is a growing interest of mobile device users as it allows the users to be in their online social community despite their mobility. This thesis highlights the basics of mobile environment, social networking and PeerHood and introduces a new approach of social networking on mobile environment, which is a new concept in mobile social networking. This approach is based on dynamic group discovery in accordance to some common user interests and management in the PeerHood environment. A reference implementation of a social networking application built on top of PeerHood is presented and it is tested and analyzed to understand the social networking on mobile environment and the new concept of dynamic group discovery in it.

Mobile Subscription Acquisition and Retention Costs - An Actvity-Based Model

The objective of this master’s thesis was to develop a model for mobile subscription acquisition cost, SAC, and mobile subscription retention cost, SRC, by applying activity-based cost accounting principles. The thesis was conducted as a case study for a telecommunication company operating on the Finnish telecommunication market. In addition to activity-based cost accounting there were other theories studied and applied in order to establish a theory framework for this thesis. The concepts of acquisition and retention were explored in a broader context with the concepts of customer satisfaction, loyalty and profitability and eventually customer relationship management to understand the background and meaning of the theme of this thesis. The utilization of SAC and SRC information is discussed through the theories of decision making and activity-based management. Also, the present state and future needs of SAC and SRC information usage at the case company as well as the functions of the company were examined by interviewing some members of the company personnel. With the help of these theories and methods it was aimed at finding out both the theory-based and practical factors which affect the structure of the model. During the thesis study it was confirmed that the existing SAC and SRC model of the case company should be used as the basis in developing the activity-based model. As a result the indirect costs of the old model were transformed into activities and the direct costs were continued to be allocated directly to acquisition of new subscriptions and retention of old subscriptions. The refined model will enable managing the subscription acquisition, retention and the related costs better through the activity information. During the interviews it was found out that the SAC and SRC information is also used in performance measurement and operational and strategic planning. SAC and SRC are not fully absorbed costs and it was concluded that the model serves best as a source of indicative cost information. This thesis does not include calculating costs. Instead, the refined model together with both the theory-based and interview findings concerning the utilization of the information produced by the model will serve as a framework for the possible future development aiming at completing the model.

Error Modeling and Accuracy Analysis of a Novel Mobile Hybrid Parallel Robot

Over the last decades, calibration techniques have been widely used to improve the accuracy of robots and machine tools since they only involve software modification instead of changing the design and manufacture of the hardware. Traditionally, there are four steps are required for a calibration, i.e. error modeling, measurement, parameter identification and compensation. The objective of this thesis is to propose a method for the kinematics analysis and error modeling of a newly developed hybrid redundant robot IWR (Intersector Welding Robot), which possesses ten degrees of freedom (DOF) where 6-DOF in parallel and additional 4-DOF in serial. In this article, the problem of kinematics modeling and error modeling of the proposed IWR robot are discussed. Based on the vector arithmetic method, the kinematics model and the sensitivity model of the end-effector subject to the structure parameters is derived and analyzed. The relations between the pose (position and orientation) accuracy and manufacturing tolerances, actuation errors, and connection errors are formulated. Computer simulation is performed to examine the validity and effectiveness of the proposed method.

Cost Optimisation of Mobile Advertising Client Data Transfer

Data traffic caused by mobile advertising client software when it is communicating with the network server can be a pain point for many application developers who are considering advertising-funded application distribution, since the cost of the data transfer might scare their users away from using the applications. For the thesis project, a simulation environment was built to mimic the real client-server solution for measuring the data transfer over varying types of connections with different usage scenarios. For optimising data transfer, a few general-purpose compressors and XML-specific compressors were tried for compressing the XML data, and a few protocol optimisations were implemented. For optimising the cost, cache usage was improved and pre-loading was enhanced to use free connections to load the data. The data traffic structure and the various optimisations were analysed, and it was found that the cache usage and pre-loading should be enhanced and that the protocol should be changed, with report aggregation and compression using WBXML or gzip.