2,881 research outputs found
Energy-water nexus:an overview of the Finnish case
Abstract. Energy and water have a significant relationship in energy and water systems. Sustainable energy and water consumption and production are becoming increasingly important. In today’s world, energy and water are basic needs for humans. The Finnish government aims to be carbon neutral by 2035, which will significantly impact the energy sector. Finland is moving away from fossil fuels and increasing renewable energy production. Renewable energy production commonly needs greater system flexibility since flexibility depends on circumstances, conditions, and resources. The increasing amount of renewable energy and decentralized production will create challenges for the Finnish energy system. Finnish water system requires energy during each process stage. Biogas is also produced from sewage in Finland. Thus, water system can impact the energy system in many ways.
The thesis will discuss the Energy-Water Nexus from a Finnish perspective. The word nexus denotes connection between systems or situations. Energy-Water Nexus means connection between water system and energy system. Research methods include a literature review and a briefcase study. The first chapter discusses nexus at a theoretical level: energy use for water and water use for energy. The second chapter includes the Energy-Water Nexus in Finland, where energy and water systems are described and evaluated. Energy sources chiefly included are hydropower, solar power, wind power, biomass, and nuclear power. The end of the second chapter shortly discusses Energy-Water Nexus from a flexibility perspective. Lastly, results are analyzed and discussed. Finnish energy and climate strategy are used as a peer material when results are analyzed. The thesis aims to convey, how efficiently Energy-Water Nexus is utilized or could be utilized in Finland.
The thesis suggests biomass, nuclear power, and hydropower to have the most significant water demand during the full life cycle. However, reached results are estimations and cannot be considered utterly correct. Biogas production from sewage will unlikely offer significant benefits to the Finnish energy industry, but it might offer on-site flexibility for treatment plants. Finnish water and wastewater treatment plants’ energy efficiency occurs to have remained at an even level during recent years. However, further studies are required to investigate water and sewage treatment plants’ energy efficiency, self-sufficient energy production, and effective wastewater treatment in biomass plants. Further research on Energy-Water Nexus is required in the future.Tiivistelmä. Energialla ja vedellä on tärkeä merkitys yhteiskunnassa, joita ilman yhteiskunnan on haastava tai jopa mahdoton toimia. Kestävä veden- ja energiankulutus sekä tuotanto ovat tärkeitä tavoitteita tulevaisuudessa. Yksi energiatuotannon suuria haasteita on energian varastointi, mihin veden ja energian nexuksella on mahdollista luoda ratkaisuja. Lisäksi Suomessa energian tuotanto on muuttumassa entistä enemmän hajautetuksi tuotannoksi, joka tuo omat haasteensa säätökykyyn.
Työn tavoitteena on tehdä kirjallisuuskatsaus Suomessa toimiviin energia- ja vesijärjestelmiin nexus näkökulmasta tarkastellen. Termi nexus tarkoittaa asiayhteyksien kytköstä ja sanan alkuperä pohjautuu latinan kielestä. Energia-Vesi Nexus tarkoittaa energian ja veden yhteyttä, mikä pohjautuu energiantuotannon vedenkäyttöön sekä veden ja jäteveden energiankulutukseen. Työn alkupuolella tarkastellaan veden ja energian yhteyttä teorian näkökannalta. Työn toisessa osiossa tarkastellaan Suomessa käytettäviä energia- ja vesijärjestelmiä. Pääasiassa tarkasteltavia energianlähteitä ovat vesivoima, biomassa, aurinkoenergia, tuulivoima ja ydinvoima. Energia- ja vesijärjestelmiä tarkastellaan työssä saatavissa olevan datan ja tutkimusten avulla. Lopussa energia-vesi nexusta tarkastellaan lyhyesti joustavuuden näkökulmasta. Kun tarkastellaan energia-vesi nexusta Suomen näkökulmasta, otetaan huomioon Suomen energia- ja ilmastostrategia. Työssä pyritään selvittämän, kuinka merkittävä vaikutus energia-vesi nexusella on Suomessa. Lisäksi selvitetään, kuinka tehokkaasti energia-vesi nexus:ta olisi mahdollista hyödyntää Suomessa.
Tutkielmassa tarkkaan lopputulokseen ei päästy, mutta huomattiin aiheen lisätutkimuksen tarve. Kuitenkin suuntaa antavia päätelmiä saatiin kuten, että biomassan tuotannolla on suuri vedentarve verrattuna muihin energianlähteisiin. Biomassan tuotannon vedenkulutusta on tärkeä tutkia, koska Suomen energiantuotanto hyvin riippuvainen bioenergiasta. Suomessa tulevaisuuden energiastrategioiden muodostamisessa olisi mahdollisesti tarve huomioida paremmin vedenkäyttö ja energianlähteiden joustavuus mahdollisuudet. Lyhyessä Tampereen Vesi case- tutkimuksessa huomattiin, että energiakäyttö vesi- ja jätevesilaitoksilla on pysynyt lähes samana vuosien ajan, mikä voi indikoida energiatehokkuuden tasaantumista. Kuitenkin lisätutkimuksia vaadittaisiin vesi- ja jätevesilaitosten energiatehokkuudesta ja energiantuotannon omavaraisuudesta sekä jätevedenpuhdistuksesta biomassaa tuottavilla laitoksilla
Representation of Nelson Algebras by Rough Sets Determined by Quasiorders
In this paper, we show that every quasiorder induces a Nelson algebra
such that the underlying rough set lattice is algebraic. We
note that is a three-valued {\L}ukasiewicz algebra if and only if
is an equivalence. Our main result says that if is a Nelson
algebra defined on an algebraic lattice, then there exists a set and a
quasiorder on such that .Comment: 16 page
Mapping EK Draconis with PEPSI - Possible evidence for starspot penumbrae
We present the first temperature surface map of EK Dra from
very-high-resolution spectra obtained with the Potsdam Echelle Polarimetric and
Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope. Changes in
spectral line profiles are inverted to a stellar surface temperature map using
our Map code. The long-term photometric record is employed to compare our
map with previously published maps. Four cool spots were reconstructed, but no
polar spot was seen. The temperature difference to the photosphere of the spots
is between 990 and 280K. Two spots are reconstructed with a typical solar
morphology with an umbra and a penumbra. For the one isolated and relatively
round spot (A), we determine an umbral temperature of 990K and a penumbral
temperature of 180K below photospheric temperature. The umbra to photosphere
intensity ratio of EK Dra is approximately only half of that of a comparison
sunspot. A test inversion from degraded line profiles showed that the higher
spectral resolution of PEPSI reconstructs the surface with a temperature
difference that is on average 10% higher than before and with smaller surface
areas by 10-20%. PEPSI is therefore better suited to detecting and
characterising temperature inhomogeneities. With ten more years of photometry,
we also refine the spot cycle period of EK Dra to 8.90.2 years with a
continuing long-term fading trend. The temperature morphology of spot A so far
appears to show the best evidence for the existence of a solar-like penumbra
for a starspot. We emphasise that it is more the non-capture of the true umbral
contrast rather than the detection of the weak penumbra that is the limiting
factor. The relatively small line broadening of EK Dra, together with the only
moderately high spectral resolutions previously available, appear to be the
main contributors to the lower-than-expected spot contrasts when comparing to
the Sun.Comment: Accepted for A&
The Electroweak Phase Transition in Ultra Minimal Technicolor
We unveil the temperature-dependent electroweak phase transition in new
extensions of the Standard Model in which the electroweak symmetry is
spontaneously broken via strongly coupled, nearly-conformal dynamics achieved
by the means of multiple matter representations. In particular, we focus on the
low energy effective theory introduced to describe Ultra Minimal Walking
Technicolor at the phase transition. Using the one-loop effective potential
with ring improvement, we identify regions of parameter space which yield a
strong first order transition. A striking feature of the model is the existence
of a second phase transition associated to the electroweak-singlet sector. The
interplay between these two transitions leads to an extremely rich phase
diagram.Comment: 38 RevTeX pages, 9 figure
Nitric oxide mediates interleukin-1 induced inhibition of glycosaminoglycan synthesis in rat articular cartilage
Interleek-1β (IL-1) is a key mediator of cartilage matrix degradation in osteoarthritis and rheumatoid arthritis. It was found that the IL-1-induced suppression of glycosaminoglycan (GAG) synthesis in rat articular cartilage occurred simultaneously with the accumulation of nitrite (a metabolite of nitric oxide (NO) in aqueous milieu) in the culture medium. NO-synthase inhibitors, L-NMMA and L-NIO, inhibited both these IL-1 effects. Dexamethasone suppressed GAG synthesis additively to IL-1, but did not alter nitrite accumulation. Three NO-donors (GEA 3175, SNAP and SIN-1) also had an inhibitory effect on cartilage GAG synthesis. Therefore, it is concluded that IL-1 induced suppression of GAG synthesis in rat articular cartilage is mediated by the production of NO
Information completeness in Nelson algebras of rough sets induced by quasiorders
In this paper, we give an algebraic completeness theorem for constructive
logic with strong negation in terms of finite rough set-based Nelson algebras
determined by quasiorders. We show how for a quasiorder , its rough
set-based Nelson algebra can be obtained by applying the well-known
construction by Sendlewski. We prove that if the set of all -closed
elements, which may be viewed as the set of completely defined objects, is
cofinal, then the rough set-based Nelson algebra determined by a quasiorder
forms an effective lattice, that is, an algebraic model of the logic ,
which is characterised by a modal operator grasping the notion of "to be
classically valid". We present a necessary and sufficient condition under which
a Nelson algebra is isomorphic to a rough set-based effective lattice
determined by a quasiorder.Comment: 15 page
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