Air defence in Northern Europe

Finnish Defence Studies is published under the auspices of the National Defence College, and the contributions reflect the fields of research and teaching of the College. Finnish Defence Studies will occasionally feature documentation on Finnish Security Policy. Views expressed are those of the authors and do not necessarily imply endorsement by the National Defence College.

Sähköautojen akkuteknologioiden tilannekatsaus

Tämän kandidaatintyön tavoitteena oli tutkia sähköautoissa käytettäviä akkuteknologioita ja verrata niiden ominaisuuksia keskenään sekä sähköautojen asettamien akkuvaatimusten kanssa. Akkuteknologiakartoituksen ja ominaisuusvertailun avulla tutkimuksessa oli tarkoitus selvittää sähköautojen akkujen kehitystä menneestä nykyhetkeen ja luoda katsaus akkuteknologian tulevaisuuteen. Tutkimuksessa painotettiin akkujen suorituskykynäkökulmaa, mutta tutkimuksessa otettiin kantaa myös eri akkuteknologioiden turvallisuuteen, ympäristötekijöihin ja hintaan. Työ toteutettiin kirjallisuustutkimuksena ja lähteinä käytettiin alan kirjallisuutta, IEEE artikkeleita, tutkimusraportteja ja verkkodokumentteja. Lisäksi tutkimuksessa hyödynnettiin akku- ja sähköautovalmistajilta saatavaa tietoa, johon suhtauduttiin varauksin. Tutkimuksessa kävi ilmi, että erilaisia litiumioniakkuteknologioita käytetään tällä hetkellä eniten sekä täyssähköautoissa että pistokehybrideissä. Huomattiin, että akkujen suorituskyvyn kehittyminen on nopeutunut viime vuosina. Erityisesti akkujen energianvarastointikykyyn vaikuttavat ominaisenergiatasot ovat kasvaneet selkeästi. Nykyisen kehittyneen litiumioniakkuteknologian todettiin täyttävän jo osittain lähivuosien suorituskykytavoitteet. Tutkimuksessa tultiin siihen tulokseen, että litiumrikkiakkuteknologia voi korvata litiumioniakkuteknologian ainakin täyssähköautoissa parempien ominaisenergiatasojen ja halvempien valmistuskustannuksien takia. Myös litiumilma-akkuteknologialla havaittiin olevan mahdollisuuksia haastaa muut litiumakkuteknologiat seuraavalla vuosikymmenellä. Tutkimuksen johtopäätöksenä todetaan, että sähköautot voivat kaupallistua laajemmin lähivuosina akkujen suorituskykyominaisuuksien kehittyessä jatkuvasti. Suorituskykyominaisuuksien parantuminen tulee todennäköisesti johtamaan siihen, että täyssähköautot yleistyvät enemmän ja pistokehybridit tulevat jäämään sähköautojen välivaiheeksi. Uusien akkuteknologioiden käyttöönotto kaupallisiin sähköautoihin voi viedä kuitenkin odotettua kauemmin, sillä akut tarvitsevat huolellista testausta ja käyttöönotto edellyttää, että kaikki ominaisuudet ovat vaaditulla tasolla.

Natural freeze crystallization : purification of aqueous Na2SO4 solutions with cold air

The aim of this thesis was to examine efficiency of freeze crystallization and eutectic freeze crystallization in purification of wastewater by imitating natural freezing. In addition, a mathematic model based on heat transfer to determine ice thickness and ice growth rate was examined. Also, the amount of sodium sulfate crystallized at the eutectic point was under investigation. In literature part, advantages and applications of the freeze crystallization are discussed, and possibility to apply it in Northern hemisphere winter weather conditions is under study. Furthermore, main sources of sodium sulfate from Finnish industries are described. The experiments were carried out in modified chest freezer, where a fan was placed in order to obtain laminar air flow inside. Picolog PT-104 data logger was used to monitor temperature changes in the salt-water solution, and constant temperature was maintained in the crystallizer with Lauda RP 850 thermostat. The impurity of formed ice layer was determined by weighing ice samples after experiment and again after 24 hours drying to full dryness in oven. Volume of salt-water solution was also measured after experiment. The highest purity of formed ice layer was obtained with small temperature difference and with long freezing time. On the other hand, the amount of crystallized sodium sulfate was its greatest with long freezing time and higher temperature difference. The results obtained by the mathematic model and empirical results did not differ significantly in most of the experiments. However, the difference increased when salt-water mixture reached its eutectic point, leading to simultaneous ice and salt crystallization. Eutectic point was reached only with the highest salt concentration with one exception. In these cases, calculated values were in many cases greater than the experimental ones. In winter weather conditions freeze crystallization is cost-effective wastewater treatment method and rather simple. Nonetheless, the efficiency and separation rate are strongly depended on ambient temperature and its changes

Recognition of nucleic acids by metal ion complexes

Metal-ion-mediated base-pairing of nucleic acids has attracted considerable attention during the past decade, since it offers means to expand the genetic code by artificial base-pairs, to create predesigned molecular architecture by metal-ion-mediated inter- or intra-strand cross-links, or to convert double stranded DNA to a nano-scale wire. Such applications largely depend on the presence of a modified nucleobase in both strands engaged in the duplex formation. Hybridization of metal-ion-binding oligonucleotide analogs with natural nucleic acid sequences has received much less attention in spite of obvious applications. While the natural oligonucleotides hybridize with high selectivity, their affinity for complementary sequences is inadequate for a number of applications. In the case of DNA, for example, more than 10 consecutive Watson-Crick base pairs are required for a stable duplex at room temperature, making targeting of sequences shorter than this challenging. For example, many types of cancer exhibit distinctive profiles of oncogenic miRNA, the diagnostics of which is, however, difficult owing to the presence of only short single stranded loop structures. Metallo-oligonucleotides, with their superior affinity towards their natural complements, would offer a way to overcome the low stability of short duplexes. In this study a number of metal-ion-binding surrogate nucleosides were prepared and their interaction with nucleoside 5´-monophosphates (NMPs) has been investigated by 1H NMR spectroscopy. To find metal ion complexes that could discriminate between natural nucleobases upon double helix formation, glycol nucleic acid (GNA) sequences carrying a PdII ion with vacant coordination sites at a predetermined position were synthesized and their affinity to complementary as well as mismatched counterparts quantified by UV-melting measurements.

Real-time adaptive control of ultra-fast laser scribing process with spectrometer online monitoring

There exist several researches and applications about laser welding monitoring and parameter control but not a single one have been created for controlling of laser scribing processes. Laser scribing is considered to be very fast and accurate process and thus it would be necessary to develop accurate turning and monitoring system for such a process. This research focuses on finding out whether it would be possible to develop real-time adaptive control for ultra-fast laser scribing processes utilizing spectrometer online monitoring. The thesis accurately presents how control code for laser parameter tuning is developed using National Instrument's LabVIEW and how spectrometer is being utilized in online monitoring. Results are based on behavior of the control code and accuracy of the spectrometer monitoring when scribing different steel materials. Finally control code success is being evaluated and possible development ideas for future are presented.

Kulutuselektroniikan akkujen tekniset ominaisuudet ja markkinaosuudet 2015

Työssä tutkittiin kirjallisuustyönä akkuteknologian nykytilaa ja markkinoita kulutuselektroniikan osalta. Työssä tehtiin myös katsaus potentiaalisiin tulevaisuuden akkuteknologioihin. Työssä havaittiin, että kulutuselektroniikassa ainoat suuresti käytetyt akkutyypit ovat nikkelimetallihybridi- (NiMH) ja litiumioniakut (Li-ion). Tärkeimpänä ominaisuutena kulutuselektroniikassa akuilla yleensä pidetään kapasiteettia, jossa Li-ion akut ovat selvästi parempia jopa kaksinkertaisen energiatiheyden takia. Li-ion akuilla voidaan saavuttaa myös moninkertainen käyttöikä lataussykleinä ja moninkertainen purkausvirta, riippuen käytetystä katodimateriaalista. NiMH akuilla etuna on lähinnä halvempi hinta ja parempi turvallisuus. Toisaalta myös pieni jännite voidaan laskea hyväksi puoleksi, koska NiMH akuilla voidaan korvata kertakäyttöisiä alkaliparistoja. Vuonna 2012 Li-ion akkuja myytiin kapasiteetissa mitattuna jopa kahdeksan kertaa enemmän kuin NiMH akkuja ja myyntimäärien ennustetaan myös kasvavan tulevaisuudessa. Liion akkujen myyntimääristä suurin osa oli kulutuselektroniikan käyttökohteisiin ja jopa kaksi kolmasosaa oli kannettavien tietokoneiden ja kännyköiden akkuja. Uusia akkuteknologioita ja Li-ion akkujen parannuksia on paljon kehitteillä, mutta suurimman potentiaalin ja myös suuret ongelmat kaupallistumiseen omaa litium-ilma akut. Lyhyemmällä aikavälillä potentiaalisia teknologioita ovat litium-rikki akut, sekä nykyisiin Li-ion akkuihin kehitteillä olevat anodimateriaalit kuten esim. pii ja alumiini/titaani, joiden ongelmiin on löydetty ratkaisuja nanoteknologiasta.

Performance Degradation Modelling and Techno-Economic Analysis of Lithium-Ion Battery Energy Storage Systems

Transmission system operators and distribution system operators are experiencing new challenges in terms of reliability, power quality, and cost efficiency. Although the potential of energy storages to face those challenges is recognized, the economic implications are still obscure, which introduce the risk into the business models. This thesis aims to investigate the technical and economic value indicators of lithium-ion battery energy storage systems (BESS) in grid-scale applications. In order to do that, a comprehensive performance lithium-ion BESS model with degradation effects estimation is developed. The model development process implies literature review on lifetime modelling, use, and modification of previous study progress, building the additional system parts and integrating it into a complete tool. The constructed model is capable of describing the dynamic behavior of the BESS voltage, state of charge, temperature and capacity loss. Five control strategies for BESS unit providing primary frequency regulation are implemented, in addition to the model. The questions related to BESS dimensioning and the end of life (EoL) criterion are addressed. Simulations are performed with one-month real frequency data acquired from Fingrid. The lifetime and cost-benefit analysis of the simulation results allow to compare and determine the preferable control strategy. Finally, the study performs the sensitivity analysis of economic profitability with variable size, EoL and system price. The research reports that BESS can be profitable in certain cases and presents the recommendations.

Quest/ion of Identities in African American Feminist Postmodern Drama: A Study of Selected Plays by Suzan-Lori Parks

Innovative and unconventional, Pulitzer Prize-winning playwright Suzan-Lori Parks belongs to the continuum of African American playwrights who have contributed to the quest/ion – the quest for and question – of identities for African Americans. Her plays are sites in which the quest/ion of identities for African Americans is pursued, raised and enacted. She makes use of both page and stage to emphasize the exigency of reshaping African Americans’ identities through questioning the dominant ideologies and metanarratives, delegitimizing some of the prevailing stereotypes imposed on them, drawing out the complicity of the media in perpetuating racism, evoking slavery, lynching and their aftereffects, rehistoricizing African American history, catalyzing reflections on the various intersections of sex, race, class and gender orientations, and proffering alternative perspectives to help readers think more critically about issues facing African Americans. In my dissertation, I approach three plays by Parks – The Death of the Last Black Man in the Whole Entire World (1990), Venus (1996) and Fucking A (2000) – from the standpoints of postmodern drama and African American feminism with a focus on the terrains that reflect the quest/ion of identities for African Americans, especially African American women. I argue that postmodern drama and African American feminism provide the ground for Parks to promote the development of a political agenda in order to call into question a number of dominant ideologies and metanarratives with regard to African Americans and draw upon the roles of those metanarratives as a powerful apparatus of racial and sexual oppressions. I also explore how Parks engages with postmodern drama and African American feminism to incorporate her own mininarratives in the dominant discourses. I argue that Parks in these plays uses postmodern drama and African American feminism to encourage reflections on intersectionality in order to reveal the concerns of African Americans, particularly African American women. Her plays challenge the dominant order of hierarchy and patriarchy, while in some cases urging unity and solidarity between African American men and women by showing how unity and solidarity can help them confront race, class and gender oppressions. Furthermore, I discuss how the utilization of postmodern techniques and devices helps Parks to transform the conventional features of playwriting, to create incredulity toward the dominant systems of oppression and to incorporate her mininarratives within the context of dominant discourses.

La flûte enchantée. Ah! l'ingrat par son silence : air de Pamina / Mozart, comp.. Roméo et Juliette. Ah! je veux vivre dans le rêve : valse / Gounod, comp. ; Mme Ritter Ciampi, S ; accompagnement d'orchestre

Comprend : La flûte enchantée ; Roméo et Juliette