Venus-Solar Wind Interaction: Asymmetries and the Escape of O+ Ions

We study the interaction between Venus and the solar wind using a global three-dimensional self-consistent quasi-neutral hybrid (QNH) model. The model treats ions (H+, O+) as particles and electrons as a massless charge neutralising fluid. In the analysed Parker spiral interplanetary magnetic field (IMF) case (IMF = [8.09, 5.88, 0] nT) a notable north-south asymmetry of the magnetic field and plasma exists, especially in the properties of escaping planetary O+ ions. The asymmetry is associated with ion finite gyroradius effects. Furthermore, the IMF x-component results in a dawn-dusk asymmetry. Overall, the QNH model is found to reproduce the main observed plasma and magnetic field regions (the bow shock, the magnetosheath, the magnetic barrier and the magnetotail), implying the potential of the developed model to study the Venusian plasma environment and especially the non-thermal ion escape.Comment: 10 pages, 22 figures, accepted for Planetary and Space Scienc

Development process and evaluation of a customer service chat application

Abstract. This thesis presents a customer service chat application: Livezhat mobile application. Its purpose is to allow customer service representatives chat with website visitors in real time, independent of the location. We examine the functional requirements of such an application. The requirements are: interactivity, enhancing customer relationships and satisfaction, good quality and fulfilling a need. The application is communicating with two servers to provide notifications and enable information exchange. It was found to enhance customer relationships with its quality and interactivity. According to survey evaluation, the application was easy to use and appealing. Out of two customers who used the application during a test period, one used the application rather much. Other feedback from the evaluation provided us a chance to improve the application in the future. The thesis’ contributions are: the design, implementation and evaluation of a novel customer service chat application used in mobile devices.Asiakaspalvelun chat-sovelluksen kehitys ja arviointi. Tiivistelmä. Tämä diplomityö esittelee asiakaspalvelun chat-sovelluksen: Livezhat mobiilisovellus (Livezhat mobile application). Sen tarkoitus on antaa asiakaspalveluhenkilökunnalle mahdollisuus keskustella (chattailla) verkkosivuvierailijoiden kanssa reaaliajassa, sijainnista riippumatta. Työssä tutkimme tällaisen sovelluksen toiminnallisia vaatimuksia. Vaatimukset ovat: interaktiivisuus, asiakassuhteiden ja asiakastyytyväisyyden parantaminen, hyvä laatu ja tarpeen täyttäminen. Sovellus kommunikoi kahden serverin kanssa, jotka mahdollistavat ilmoituksien (notifications) kulkemisen ja tiedonsiirron. Se parantaa tutkimuksen mukaan asiakassuhteita laatunsa ja interaktiivisuutensa vuoksi. Arviointikyselyn mukaan sovellusta oli helppo käyttää ja se näyttää hyvältä. Testiperiodin aikana kaksi asiakasta käytti sovellusta, ja heistä toinen käytti sitä paljon. Arviointikyselystä saatu muu palaute antoi meille mahdollisuuden parantaa sovellusta tulevaisuudessa. Diplomityön työpanostus on: uuden mobiililaitteissa käytettävän asiakaspalvelun chat-sovelluksen suunnittelu, toteutus ja arviointi

A Model for the Forest Sector

Dynamic linear programming models have been extensively used at IIASA to examine the long-term consequences of various economic policies and scenarios. Applications have included energy supply prospects, alternative paths for regional development, and the planned improvement of agricultural production. This report develops the methodology further and presents an application to the study of forestry and the forest-based industries; the Finnish forestry sector is used as an illustrative example

A Model for the Forest Sector

This paper describes a dynamic linear programming model for studying long-range development alternatives of forestry and forest based industries at a national and regional level. The Finnish forest sector is used as an object of implementation and for numerical examples. Our model is comprised of two subsystems, the forestry and the industrial subsystem, which are linked to each other through the wood supply. The forestry submodel describes the development of the volume and age distribution of different tree species within the nation or its subregions. In the industrial submodel we consider various production activities, such as saw mill industry, panel industry, pulp and paper industry, as well as further processing of primary products. For a single product, alternative technologies may be employed. Thus, the production process is described by a small Leontief model with substitution. Besides supply of wood and demand of wood products, production is restricted through labor availability, production capacity, and financial resources. The production activities are grouped into financial units and the investments are made within the financial resources of such units. Objective functions related to GNP, balance of payments, employment, wage income, stumpage earnings, and industrial profit have been formulated. Terminal conditions have been proposed to be determined through an optimal solution of a stationary model for the whole forest sector. The structure of the integrated forestry-forest industry model is given in the canonical form of dynamic linear programs for which special solution techniques may be employed. Two versions of the Finnish forest sector models have been implemented for the interactive mathematical programming system called SESAME, and a few numerical runs have been presented to illustrate possible use of the model

Systems Analysis for the Forest Sector

This article is an overview of systems analysis in forestry and forest industries. The issues covered range from forest management and forest industrial strategy to international trade in forest products and structural change in the forest sector worldwide. The methodologies discussed include mathematical models of economies, statistics, and operations research

Molecular characterisation of infectious pancreatic necrosis viruses isolated from farmed fish in Finland

Abstract Infectious pancreatic necrosis virus (IPNV) has been isolated annually since 1987 from salmonids without clinical signs at coastal fish farms in Finland. In the inland area, viral isolations were rare until 2012, when IPNV was detected at several freshwater fish farms. Between 2013 and 2015, the infection spread and IPNV was continuously isolated from several farms, both inland and on the coast. The aim of this study was to genetically characterise the IPNV isolates collected from Finnish coastal and inland fish farms over the last 15 years, and to detect genetic changes that may have occurred in the virus populations during the study period. The partial VP2 gene sequence from 88 isolates was analysed. In addition, a complete genomic coding sequence was obtained from 11 isolates. Based on the genetic analyses, Finnish IPNV isolates belong to three genogroups: 2, 5 and 6. The genetic properties of the isolates appear to vary between inland farms producing juveniles and food fish farms in the coastal region: the inland farms harboured genogroup 2 isolates, whereas at coastal farms, all three genogroups were detected. Little genetic variation was observed within the Finnish genogroup 2 and 5 isolates, whereas among the genogroup 6 isolates, two subgroups were detected. All isolates studied demonstrated amino acid patterns in the viral VP2 gene previously associated with avirulence. However, increased mortality was detected at some of the farms, indicating that more research is needed to clarify the relationship between the pathogenicity and genetic properties of IPNV isolates from different genogroups

Systems Analysis in Forestry and Forest Industries

The purpose of this book is to present a variety of articles revealing the state of the art of applications of systems analysis techniques to problems of the forest sector. Such applications cover a vast range of issues in forestry and the forest industry. They include the dynamics of the forest ecosystem, optimal forest management, the roundwood market, forest industrial strategy, regional and national forest sector policy as well as international trade in forest products. Forest industrial applications at mill level, such as optimal paper trimming, cutting, and production scheduling, are however, excluded

Generation of Anatomically Inspired Human Airway Tree Using Electrical Impedance Tomography: A Method to Estimate Regional Lung Filling Characteristics

The purpose of lung recruitment is to improve and optimize the air exchange flow in the lungs by adjusting the respiratory settings during mechanical ventilation. Electrical impedance tomography (EIT) is a monitoring tool that allows to measure regional pulmonary filling characteristics or filling index (FI) during ventilation. The conventional EIT system has limitations which compromise the accuracy of the FI. This paper proposes a novel and automated methodology for accurate FI estimation based on EIT images of recruitable regional collapse and hyperdistension during incremental positive end-expiratory pressure. It identifies details of the airway tree (AT) to generate a correction factor to the FIs providing an accurate measurement. Multiscale image enhancement followed by identification of the AT skeleton with a robust and self-exploratory tracing algorithm is used to automatically estimate the FI. AT tracing was validated using phantom data on a ground-truth lung. Based on generated phantom EIT images, including an established reference, the proposed method results in more accurate FI estimation of 65% in all quadrants compared with the current state-of-the-art. Measured regional filling characteristics were also examined by comparing regional and global impedance variations in clinically recorded data from ten different subjects. Clinical tests on filling characteristics based on extraction of the AT from the resolution enhanced EIT images indicated a more accurate result compared with the standard EIT images

Analytic theory of correlation energy and spin polarization in the 2D electron gas

We present an analytic theory of the pair distribution function and the ground-state energy in a two-dimensional (2D) electron gas with an arbitrary degree of spin polarization. Our approach involves the solution of a zero-energy scattering Schr\"odinger equation with an effective potential which includes a Fermi term from exchange and kinetic energy and a Bose-like term from Jastrow-Feenberg correlations. The form of the latter is assessed from an analysis of data on a 2D gas of charged bosons. We obtain excellent agreement with data from quantum Monte Carlo studies of the 2D electron gas. In particular, our results for the correlation energy show a quantum phase transition occurring at coupling strength $r_s\approx 24$ from the paramagnetic to the fully spin-polarized fluid.Comment: 9 pages, 4 figure

Electrical impedance tomography reveals pathophysiology of neonatal pneumothorax during NAVA

Pneumothorax is a potentially life‐threatening complication of neonatal respiratory distress syndrome (RDS). We describe a case of a tension pneumothorax that occurred during neurally adjusted ventilatory assist (NAVA) in a preterm infant suffering from RDS. The infant was included in a multicenter study examining the role of electrical impedance tomography (EIT) in intensive care and therefore continuously monitored with this imaging method. The attending physicians were blinded for EIT findings but offline analysis revealed the potential of EIT to clarify the underlying cause of this complication, which in this case was heterogeneous lung disease resulting in uneven ventilation distribution. Instantaneous increase in end‐expiratory lung impedance on the affected side was observed at time of the air leak. Real‐time bedside availability of EIT data could have modified the treatment decisions made