d0 Ferromagnetic Interface Between Non-magnetic Perovskites

We use computational and experimental methods to study d0 ferromagnetism at a charge- imbalanced interface between two perovskites. In SrTiO3/KTaO3 superlattice calculations, the charge imbalance introduces holes in the SrTiO3 layer, inducing a d0 ferromagnetic half-metallic 2D electron gas at the interface oxygen 2p orbitals. The charge imbalance overrides doping by vacancies at realistic concentrations. Varying the constituent materials shows ferromagnetism to be a gen- eral property of hole-type d0 perovskite interfaces. Atomically sharp epitaxial d0 SrTiO3/KTaO3, SrTiO3 /KNbO3 and SrTiO3 /NaNbO3 interfaces are found to exhibit ferromagnetic hysteresis at room temperature. We suggest the behavior is due to high density of states and exchange coupling at the oxygen t1g band in comparison with the more studied d band t2g symmetry electron gas.Comment: 5 pages, 5 figure

Tuotekustannuslaskentamallin kehittäminen elintarvikealan yritykseen

Työn tavoitteena oli kehittää tuotekustannuslaskentamalli elintarvikealan yritykseen. Laskentamallin avulla halutaan saada tarkempaa tietoa tuotteiden kustannuksista ja kannattavuuksista. Työ muodostuu teoreettisesta kirjallisuusselvityksestä sekä empiirisestä case-tutkimuksesta. Aineiston perusteella kohdeyritykselle saatiin kehitettyä tuotekustannuslaskentamalli. Työn tutkimusote on konstruktiivinen. Laskentamallin kehittäminen edellytti välillisten kustannusten kohdistamisperiaatteiden määrittämistä. Välilliset kustannukset kohdistetaan perinteisellä kaksivaiheisella menetelmällä. Kustannukset kohdistetaan ensin niille kuuluville kustannuspaikoille. Kustannuspaikoilta kustannukset kohdistetaan edelleen tuoteryhmille ja tuotteille. Kohdeyrityksen tuotekustannuslaskenta on aikaisemmin perustunut ainoastaan standardikustannuslaskentaan. Kehitetyn kustannuslaskentamallin avulla tuotteiden kustannuksista ja kannattavuudesta saadaan tarkempaa tietoa, koska välillisten kustannusten kohdistamiseen luotiin selkeät menetelmät. Parantunutta kus-tannustietoa voidaan hyödyntää tuotteita koskevissa päätöksentekotilanteissa.The aim of this study is to develop the product cost model in food industry. With this costing model one can examine costs and profitability of products. The study consists of theoretical literature survey and empirical case study. The costing model was build based on theoretical and empirical material. The nature of this study is constructive. The new product costing model allocates indirect costs and depreciations to products. The new costing model is based traditional two stage costing method. At the first stage costs are allocated to costs centers. At the second stage costs are allocated further to products. Company’s product costing has only been based on standard costing. Determine the principles of indirect costs allocation was needed to develop new product costing model. With the developed costing model one can get better information because of indirect cost allocation. Better cost information support decision making

Tunnelikasvatuksen vaikutus kesävadelman satoon ja marjan laatuun

Vadelman (Rubus idaeus L.) saatavuus tuoremarjana on ollut Suomessa epävarmaa ja rajoittunut muutamaan heinä-elokuun viikkoon. Viileä sää ja tuuli heikentävät vadelman kasvua, ja rankkasateet lisäävät harmaahomeen esiintymistä marjoissa. Marja kestää säilytystä ja kuljetusta erittäin huonosti hauraan rakenteensa vuoksi. Satotaimia käyttämällä tuoreen vadelman tarjontaa voidaan laajentaa sesongin ulkopuolelle. Siksi Suomessakin on otettu käyttöön muualla Euroopassa suosittu käytäntö viljellä vadelmaa säältä suojaavan katteen alla, eli kausihuoneessa tai tunnelissa. Tunneliviljelyn onkin jo todettu lisäävän vadelman satoa, vähentävän harmaahomeesta aiheutuvia satotappioita ja mahdollistavan satokauden ajoittamisen viljelijälle edulliseen ajankohtaan. Tässä tutkimuksessa verrattiin kolmen tunnelissa ja avomaalla viljellyn kesävadelmalajikkeen satoa, marjan aistittavaan ja ravitsemukselliseen laatuun vaikuttavia tekijöitä sekä marjan varastointikestävyyttä. Kokeessa käytettiin kesävadelmalajikkeita ’Glen Ample’, ’Glen Dee’ ja ’Maurin Makea’. Marjan aistittavaa laatua arvioitiin marjan sokeri- ja happopitoisuuden kautta. Marjan bioaktiivisten yhdisteiden määrää tutkittiin mittaamalla marjan sisältämien fenoliyhdisteiden kokonaispitoisuus Fast Blue BB -menetelmällä ja marjan antioksidanttiaktiivisuus FRAP-menetelmällä. Varastointikestävyys mitattiin +5 °C:ssa ja huoneenlämmössä suoritetulla varastointikokeella. Tunnelissa vadelman kokonaissato versoa kohti oli 99 % suurempi kuin avomaalla. Marjapaino ei riippunut kasvatusolosuhteista vaan oli lajikekohtainen ominaisuus. Avomaalla kasvaneiden marjojen sokeri- ja happopitoisuudet olivat suuremmat kuin tunnelissa. Marjojen kokonaisfenolipitoisuudessa oli suuria lajikekohtaisia eroja, mutta antioksidanttiaktiivisuudessa ei ollut eroja lajikkeiden eikä kasvatusolosuhteiden välillä. Varastointikokeessa +5 °C:ssa havaittiin, että avomaalta poimitut marjat säilyivät kiinteinä pitempään, mutta niihin ilmaantui harmaahometta jo ensimmäisen viikon aikana. Paras varastointikestävyys oli ’Glen Ample’ -lajikkeen marjoilla. Tulosten perusteella tunnelikasvatus suurentaa vadelman satoa heikentämättä marjan ravitsemuksellista laatua. Tunnelissa kasvaneiden vadelman marjojen pienemmät sokeri- ja happopitoisuudet voivat vaikuttaa marjojen makuun.Protected cultivation of raspberries (Rubus idaeus L.) has increased its popularity in Finland. One reason is that the fruit is extremely sensitive to rainy weather during its development. The raspberry plant itself is sensitive to wind and low temperatures, which can reduce growth. In Europe most of the raspberry is grown in protected cultivation, and this technology is now becoming popular in Finland. A high tunnel is a cost-efficient way to protect the plants against rainy weather and extend the harvest season. The protected cultivation has been shown to increase the yield and cropping potential of raspberry and reduce the gray mold in the berries. In human diet, berries are among the richest sources of antioxidants. In raspberry, the most important antioxidants are vitamin C (20 %) and phenolic compounds (80 %). Among phenolic compounds, ellagitannins and anthocyanins give the greatest contribution to antioxidant activity. The aim of this thesis was to study the yield, sensory quality, nutritional quality and shelf life of three floricane fruiting raspberry cultivars grown in high tunnel and open field. Cultivars ’Glen Ample, ’Glen Dee’ and ’Maurin Makea’ were used in the study. Sugar and acid content of raspberry were examined to get an overview of sensory quality. The nutritional quality was studied with an antioxidant activity assay (using FRAP method) and total phenolics assay (using Fast Blue BB method). The shelf life was tested both in +5 °C and in room temperature. The average total yield per cane was 99 % greater in tunnel than in the open field, whereas both sugar and acid content of the berry were greater in open field. Berry weight and total phenolics content were strongly cultivar dependent characteristics. The results of the antioxidant activity assay did not show significant differences between either growing conditions or the cultivars. The shelf life in room temperature was equally weak for all samples, but in +5 °C storage the open field raspberries developed symptoms of gray mold earlier than those picked from the tunnel. The conclusion is that contents of health beneficial compounds in berries were not affected in tunnel cultivation, but berry taste may be affected, as differences in sugar and acid contents were observed

Solid-liquid interfacial properties of refractory metals from atomistic simulations

In this work, we use molecular dynamics simulations to compute anisotropic solid-liquid interfacial properties for refractory metals Mo, Nb, Ta, V and W using an accurate tabulated Gaussian approximation potential. The capillary fluctuation method is used for calculating the anisotropic solid-liquid interfacial free energy, and non-equilibrium free solidification simulations are used for estimating the kinetic coefficient and its anisotropy. A layered thermostat approach is used for the non-equilibrium simulations, and the number of thermostats required to maintain isothermal solidification conditions is discussed. We find that the anisotropy of the solid-liquid interfacial free energies and kinetic coefficients is weak but follows consistently ordering 100 &gt; 110. Additionally, we compute the self-diffusivities of the liquid metals and their temperature dependence.</p

Gli italianismi nella lingua speciale della gastronomia: uno studio su libri di cucina pubblicati in finlandese tra il 1997 e il 2016

Questa tesi di laurea studia i prestiti linguistici, in particolare gli italianismi usati nella lingua speciale della gastronomia finlandese, sulla base di quanto rilevato nei libri di cucina italiana pubblicati in Finlandia tra il 1997 e il 2016: un corpus che permette di analizzare non soltanto la formazione e le tipologie dei prestiti, ma anche l’uso e le funzioni linguistiche degli italianismi. Il riscontro lessicografico si basa sul confronto con vari dizionari, tra cui il Dizionario di italianismi in francese, inglese, tedesco (DIFIT, Accademia della Crusca, 2008) diretto da Harro Stammerjohann e le opere lessicografiche finlandesi relative alla gastronomia. Nel mio studio la definizione del termine italianismo di Stammerjohann è stata fondamentale per la distinzione tra italianismi e pseudoitalianismi: questa divisione è stata completata dalla classificazione dei calchi secondo Manfred Görlach, editore del Dictionary of European Anglicisms (2001). Inoltre, le funzioni linguistiche sono state analizzate sulla base delle metafunzioni linguistiche della teoria sistemica-funzionale introdotta da M. A. K. Halliday. Le occorrenze sono state analizzate con l’applicazione di analisi di dati testuali e concordanze AntConc, successivamente elaborate in Excel. I prestiti integrali rappresentano il 50% circa delle 4.052 occorrenze presenti nel corpus, mentre gli pseudoitalianismi rappresentano più del 50% delle 1.000 unità lessicali considerate. La grande quantità degli pseudoitalianismi è principalmente formata dai nomi finlandesi delle preparazioni alimentari a causa della formazione diversa del calco rispetto al lessema italiano, invece la grande quantità dei prestiti integrali indica il prestigio degli italianismi e il fatto che l’uso delle denominazioni italiane si è stabilizzato nella lingua finlandese. Tra le 355 unità di italianismi individuati nel corpus, figurano prestiti in diverse modalità di formazione: prestiti integrali, prestiti adattati, prestiti con chiarificante, prestiti di locuzioni, prestiti ellittici, acronimi e calchi di traduzione. Nel campo semantico delle denominazioni delle vivande troviamo il numero maggiore di italianismi, ma nelle occorrenze sono altrettanto frequenti quelle dei formati di pasta. Inoltre, negli italianismi del corpus sono state individuate 68 denominazioni che non appaiono nelle opere lessicografiche di riferimento e che possiamo considerare nuovi italianismi

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

Sensitivity analysis of a PLC-based DSSS anti-islanding system in power distribution grids

As smart grid applications, distributed generation, and microgrid technologies have become more widespread, new safety-related issues have arisen. Unintentional islanding is an example of a grid fault that may result in damage to electrical equipment and severe personal injuries. In this paper, an anti-islanding system employing power line communication (PLC) and direct-sequence spread spectrum (DSSS) modulation implemented with software-defined radios for continuous signaling is tested in a laboratory test setup. A concept of a fault detection algorithm is evaluated. A DSSS sensitivity analysis is carried out to investigate system’s performance against variation of a signal-to-noise ratio, and define optimal DSSS settings. The results of the analysis are interpreted, and conclusions are drawn. A transformer bypassing scheme allowing to increase the fault detection speed and throughput is introduced and tested, and the conditions of applicability are described. As a result of the study, recommendations for the system development are presented.Post-print / Final draf

An assessment of the diffusion of Private Mini-Grids operating in rural Kenya

High off-grid market penetration in Kenya is one of the key reasons for the fast electrification rate in the country. Solar home systems are largely deployed in remote areas, but mini-grids (MGs) are still far from exploiting their full potential. This study aims to analyze the technological innovation of privately owned mini-grids operating in remote areas of Kenya. Interactions between actors, institutions, and processes are evaluated using primary data collected from stakeholders active in the sector. Through this analysis, we evaluate whether the innovation system is in place to support the diffusion of private MGs and identify obstacles that block the advancement toward market growth.Post-print / Final draf