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Hannukainen is an old mining area, at commune of Kolari in western Finnish Lapland. Rautaruukki Oy and Outokumpu Oy mined iron, copper and cold from the area in 1978 - 1990. Area is located in the Pajala-Kolari shear zone. Kaunisvaara mining project at Sweden is related to the same shear zone. Northland Mines Finland Oy is planning to restart mining of IOCG-type ore at Hannukainen area within the next couple of years. Quaternary deposits or water resources in Hannukainen area has not been examined in detail before. The mine development site is surrounded be three rivers, Valkeajoki in east, Kuerjoki in west and Äkäsjoki in south. The stratigraphical and hydrostratigraphical field studies in Hannukainen area were made in summer 2011. Stratigraphy of the Quaternary deposits was observed from the sections of Laurinoja open pit and from test pits dug to the area. Permeability of the sediment units were measured by using ring infiltration tests and calculated from grain size evaluations made from sediment samples. Groundwater was observed by evaluating the quality and representativeness of the groundwater monitoring wells, groundwater level measurements and also laboratory analyzes of main ions, trace-elements and isotope ratios of oxygen and hydrogen. In addition to chemistry samples, electric conductivity, pH, temperature and ratio of oxygen was measured with YSI multielectrode probe from rivers and open pit ponds. Groundwater - surface water interactions were observed by taking chemistry samples, measuring river bed temperatures and by installing minipiezometers. Quaternary deposits are mostly glaciofluvial and fluvial sands and gravels instead of tills. Sorted sandy sediments related to the braided river bars formed by Muonio Ice lake spillways are found from the present valleys of River Äkäsjoki, Valkeajoki and Kuerjoki. Sand and gravel sediments have good permeability and they host considerable amounts of water. Fine sediment units are thin and as discontinuous layers they host perched groundwater and confined groundwater. From the observed 23 groundwater monitoring wells only three represented the whole saturated aquifer and altogether six were other vice usable. The most remarkable problems were the lack of installation information and shortness of monitoring wells compared to the thick quaternary deposits in the area. Acid Mine Drainage -effect (AMD) of the old open pits, waste rock area and ore deposit itself could be detected from the groundwater monitoring wells in the old mining area and from the groundwater discharging to the river Äkäsjoki. Isotope ratios, river bed temperatures and hydraulic head difference in mini- piezometers reveal that groundwater is discharging from the mine development site to the rivers surrounding it. Hannukainen area is a challenging environment for mine siting. Hydrostratigraphy in the area is complicated, permeability of the Quaternary deposits is generally good, aquifer is multileveled and rivers surrounding the area get a significant amount of their water from groundwater forming in the mine development site. Most of the present groundwater monitoring wells are unusable, and in order to monitor the groundwater reliably some new monitoring wells should be installed. Major flow direction of surface and groundwater are from the mine development site to the rivers surrounding it. Classified groundwater areas should be outlined again, because present linings do not relate to true aquifers. Location of tailings area planned to the mine development site has been reconsidered.

The topic of thesis is the wave equation. The first chapter is introduction, the overview of the thesis is presented. The second chapter treats the transport equation, which is needed to solve the wave equation. In the third chapter we discuss the d’Alembert formula, and we prove the existence and uniqueness of solution. We treat the domain of dependence and region of influence. The last chapter concentrates on solving wave equations in high dimensions by Kirchhoff’s formula, method of descent and methods of spherical means.

Google Wave is a real-time communication and collaboration system introduced in 2009. The Wave system allows multiple users to view and modify hosted conversations called waves simultaneously. A wave conversation consists of a tree-like structure of messages. The messages can contain rich text, images and other attachments. Concurrency control is handled using a technique called operational transformation. It enables users to modify a wave simultaneously without acquiring any locks. Google has released Wave protocol descriptions and other technical documentation about the implementation of Wave. Google has also released a large portion of Wave source code under an open source license. Google ended the development of Google Wave in the late 2010 but the development of Wave is continued by the Apache Software Foundation. The open source version of Wave is called Wave in a Box. Wave in a Box contains the implementations of a web-based client and a Wave server. Wave is based on a federated client-server architecture. Although the Wave client is connected only to the user's own Wave service provider, the user can still communicate with users of other service providers. Wave servers are connected to each other and communicate with each other transparently to the user. In this sense the Wave architecture resembles email architecture. In this thesis we present the design for a new peer-to-peer-based Wave system called P2P-Wave. P2P-Wave was designed to be much like the original Wave. Operational transformation is used in both systems and the same functionality is available to the user in both systems. However, the systems are very different with respect to network communication. P2P-Wave has no centralized servers; all communication happens between users' own computers through the Pastry routing system. P2P-Wave also uses the Scribe multicast system and the distributed file system Past.

Maxwell’s equations are a set of equations which describe how electromagnetic fields behave in a medium or in a vacuum. This means that they can be studied from the perspective of partial differential equations as different kinds of initial value problems and boundary value problems. Because often in physically relevant situations the media are not regular or there can be irregular sources such as point sources, it’s not always meaningful to study Maxwell’s equations with the intention of finding a direct solution to the problem. Instead in these cases it’s useful to study them from the perspective of weak solutions, making the problem easier to study. This thesis studies Maxwell’s equations from the perspective of weak solutions. To help understand later chapters, the thesis first introduces theory related to Hilbert spaces, weak derivates and Sobolev spaces. Understanding curl, divergence, gradient and their properties is important for understanding the topic because the thesis utilises several different Sobolev spaces which satisfy different kinds of geometrical conditions. After going through the background theory, the thesis introduces Maxwell’s equations in section 2.3. Maxwell’s equations are described in both differential form and timeharmonic differential forms as both are used in the thesis. Static problems related to Maxwell’s equations are studied in Chapter 3. In static problems the charge and current densities are stationary in time. If the electric field and magnetic field are assumed to have finite energy, it follows that the studied problem has a unique solution. The thesis demonstrates conditions on what kind of form the electric and magnetic fields must have to satisfy the conditions of the problem. In particular it’s noted that the electromagnetic field decomposes into two parts, out of which only one arises from the electric and magnetic potential. Maxwell’s equations are also studied with the methods from spectral theory in Chapter 4. First the thesis introduces and defines a few concepts from spectral theory such as spectrums, resolvent sets and eigenvalues. After this, the thesis studies non-static problems related to Maxwell’s equations by utilising their time-harmonic forms. In time-harmonic forms the Maxwell’s equations do not depend on time but instead on frequencies, effectively simplifying the problem by eliminating the time dependency. It turns out that the natural frequencies which solve the spectral problem we study belong to the spectrum of Maxwell’s operator iA . Because the spectrum is proved to be discrete, the set of eigensolutions is also discrete. This gives the solution to the problem as the natural frequency solving the problem has a corresponding eigenvector with finite energy. However, this method does not give an efficient way of finding the explicit form of the solution.

The World Wide Web has emerged as a powerful tool and an entity that has formed a major part of everyday human life. Since web technology has become vital to humans, it is emerging as a platform where web applications mean more than they have ever meant. This demands for the user experience to be pleasurable and fast. But the disruptions in flow in traditional web applications stop the user from getting the desired experience. Initially web browsers were developed for displaying static pages linked together and user navigated to retrieve information from a server. This phenomenon is also known as multipage paradigm. It took more than two decades to evolve from a mere information-displaying entity to an application execution platform. The Ubiquitous nature of the web changed the trends, and complex web applications started emerging. These applications on user actions reload the entire web page from the server. Client and server communicate using synchronous communication mode. User action on the client triggers a call to the server and blocks the input/output until the server responds. Even after the advancement of web technologies, the web applications multipage paradigm remains the same and so do the problems of disruption in the user experience and application workflow. This thesis analyzes the design and development of modern web applications aimed at providing new single page paradigm and asynchronous communication between the client and the server to solve problems found in the multipage web application paradigm. This thesis also discusses the tools and technologies used in building single page web applications. The new single page paradigm introduces some challenges that are also considered in this thesis. Furthermore, the thesis covers that how the new paradigm can be used to develop applications on fragmented devices. Finally, the thesis describes the implementation of an example application aimed at producing a single page paradigm.

Welcome, in this thesis, some of the higher ranked, popular web content management software (CMS), namely Drupal, WordPress, Joomla and Plone, are compared by usability, from a developer’s perspective, and by performance of the resultant site build with these CMSs, to find out, among other topics, about their potential to build websites to different needs. This thesis tries to discover if a CMS exists, in this selected group, that is a clear choice above the others in both usability and performance. A substantial portion of source material for this research comes from measurements, and small demo systems built and used, in addition to any literature sources used and experience garnered from career as a web developer. In this thesis, we provide an overview of these four selected CMS; their characteristics, statistics and how they measure up to each other. And so doing, expand upon the still narrow research done in this field.

Tässä tutkielmassa vertaillaan vertaillaan keskenään web-sovellusten käyttöliittymien automaattitestauksen menetelmiä. Tutkielmassa selvitetään mitä erityistä webohjelmistojen testaamisessa on, ja miten niitä on mahdollista testata. Tutkielmassa vertaillaan myös muutamia testiautomaation tekniikoita ja niitä hyödyntäviä ohjelmointikirjastoja ja työkaluja. Cypress on Javascript-pohjainen testiautomaatio kehys web-ohjelmistojen testaamiseen. Selenium Webdriver on Wedriver protokollaa hyödyntävä selainautomaatiokirjasto, jota käytetään mm. selainohjelmistojen testaamiseen. Sikuli on automaatiokirjasto, joka perustuu kuvantunnistukseen. Näitä kirjastoja ja niiden soveltamia tekniikoita vertaillaan keskenään niiden webohjelmistojen testaamiseen soveltuvuuden, testien kehityksen ja suorituksen tehokkuuden sekä alusta- ja selaintuen näkökulmista.

Web-palvelut ovat tekniikkana suosittu tapa toteuttaa yritysten sisäiset ja ulkoiset liiketoimintaprosessit sähköisenä palveluna. Koostamisen avulla olemassa olevista web-palveluista voidaan rakentaa uusia monipuolisempia palveluja. Tässä työssä tutkitaan, minkälainen transaktionaalisuuden taso koosteisessa web-palvelussa voidaan saavuttaa käytettävissä olevilla teknologioilla. Tämä tehdään vertailemalla web-palveluiden transaktionaalisia ominaisuuksia tietokantateoriasta tuttuihin transaktion ACID-ominaisuuksiin, sarjallistuvuusteoriaan, sekä transaktiomalleihin. Työssä tutkitaan myös sitä, tarvitaanko web-palveluiden transaktionaalisessa koostamisessa ylipäätään tietokantojen teoriasta tuttuja käsitteitä ja malleja. Tutkimuksessa syvennytään niihin web-palveluiden koostamisessa käytettäviin menetelmiin ja protokolliin, jotka tarjoavat transaktionaalisia piirteitä liiketoimintaprosessien toteuttamiseksi. Nämä ovat web-arkkitehtuuripinon WS-AtomicTransaction- ja WS-BusinessActivity -protokollat. Tulosten analysoinnissa on käytetty apuna erään matkatoimiston web-palvelua. Web-palveluiden välisten transaktioiden ACID-ominaisuudet käytiin läpi kahden web-palvelun käyttötapauksen kautta. Tuloksista selvisi, että web-palveluiden välisissä transaktioissa toteutuu ainoastaan transaktion ACID-atomisuus. Samalla selvitettiin, miten tämä saavutettu transaktionaalisuuden taso käytännössä vaikuttaa web-palveluiden väliseen toimintaan. Tutkielman tuloksien vaikutuksia web-palveluiden väliseen kanssakäyntiin arvioitiin sekä palvelun toteuttajan, että loppukäyttäjän näkökulmasta. Tuloksien perusteella kävi ilmi, että vakavien ongelmien välttämiseksi toteuttajan on tunnettava sovelluksen ongelmakenttä erityisen hyvin ja ymmärrettävä se, miten koosteisen web-palvelun transaktionaalisuuden taso vaikuttaa kyseisessä ympäristössä palvelun toimintaan. Tutkielman lopussa esitellään tämän tutkielman tuloksena syntynyt eksklusiivinen malli, jonka avulla koosteeseen osallistuvien web-palveluiden välisissä transaktioissa voidaan saavuttaa globaali ACID-eristyvyys. Mallia soveltamalla web-palvelut voivat etsiä eksklusiivista kauppaa käyviä web-palveluja SOA-arkkitehtuurimallin mukaisesti UDDI-rekisteristä, ja suorittaa näiden kanssa häiriöttämästi sarjallistuvia transaktioita. ACM Computing Classification System (CCS): - Information systems~Web services - Information systems~Database transaction processing

Web Real Time Communication (WebRTC) is a project that aims to enable plug-in free, real time communications across multiple web-browsers. With WebRTC enabled web-browsers, users can make direct browser to browser audio calls, video calls or transfer arbitrary data. In a simple network with no Network Address Translation (NAT), firewalls or HTTP-proxies, WebRTC applications work well without any problems. But in the real world, the networks are complex and clients are usually behind NAT, firewalls and (or) HTTP proxies. Introduction of such network middle boxes creates problems for WebRTC media flow, leading to a failure in WebRTC call establishment. WebRTC uses Interactive Connectivity Establishment (ICE) framework to work around the problems posed by these middle boxes. ICE uses a combination of Session Traversal Utilities for NAT (STUN) and Traversal Using Relays around NAT (TURN) depending on the network configuration and tries to give the WebRTC media the best possible chance to traverse these middle boxes. A TURN server is required to relay the WebRTC media between peers when STUN methods fail. In this work, we evaluate the different network configurations in which WebRTC peers can be present and how the WebRTC connectivity problem can be solved using the ICE framework, when peers are present in such network configurations. We also evaluate the TURN server for its computational, memory and bandwidth requirements for relaying different types of WebRTC calls.

The Streamr Network is a decentralized publish-subscribe system. This thesis experimentally compares WebSocket and WebRTC as transport protocols in the system’s d-regular random graph type unstructured stream overlays. The thesis explores common designs for publish-subscribe and decentralized P2P systems. Underlying network protocols including NAT traversal are explored to understand how the WebSocket and WebRTC protocols function. The requirements set for the Streamr Network and how its design and implementations fulfill them are discussed. The design and implementations are validated with the use simulations, emulations and AWS deployed real-world experiments. The performance metrics measured from the real-world experiments are compared to related work. As the implementations using the two protocols are separate incompatible versions, the differences between them was taken into account during analysis of the experiments. Although the WebSocket versions overlay construction is known to be inefficient and vulnerable to churn, it is found to be unintentionally topology aware. This caused the WebSocket stream overlays to perform better in terms of latency. The WebRTC stream overlays were found to be more predictable and more optimized for small payloads as estimates for message propagation delays had a MEPA of 1.24% compared to WebSocket’s 3.98%. Moreover, the WebRTC version enables P2P connections between hosts behind NATs. As the WebRTC version’s overlay construction is more accurate, reliable, scalable, and churn tolerant, it can be used to create intentionally topology aware stream overlays to fully take over the results of the WebSocket implementation.