333 research outputs found
A comparison between numerical solutions to fractional differential equations: Adams-type predictor-corrector and multi-step generalized differential transform method
In this note, two numerical methods of solving fractional differential
equations (FDEs) are briefly described, namely predictor-corrector approach of
Adams-Bashforth-Moulton type and multi-step generalized differential transform
method (MSGDTM), and then a demonstrating example is given to compare the
results of the methods. It is shown that the MSGDTM, which is an enhancement of
the generalized differential transform method, neglects the effect of non-local
structure of fractional differentiation operators and fails to accurately solve
the FDEs over large domains.Comment: 12 pages, 2 figure
Pollutant Formation in Monodisperse Fuel Spray Combustion
The combustion of liquid sprays represents an extremely important class of combustion processes. In the transition region, encompassing droplet sizes in the range of 25-80 micron diameter, the mixing and evaporation processes are both incomplete at the flame front and burning occurs in a combined diffusive and premixed fashion. Under these conditions, the relative importance of heterogeneous and homogeneous effects in dominating the combustion process is switched and gives rise to a number of interesting phenomena. NO (sub x) formation in monodisperse spray combustion was investigated with the following specific objectives: (1) to quantitatively determine the effect of droplet size, number density, etc. on NO sub x formation in monodisperse fuel spray combustion; and (2) to isolate the important physical and chemical phenomena in NO sub x formation in these combustion systems
Pihlaka (Sorbus spp.) genotüüpide viljade väärindamine funktsionaalse toidu koostisosadeks
A Thesis for applying for the degree of Doctor of Philosophy in Agriculture.Väitekiri filosoofiadoktori kraadi taotlemiseks põllumajanduse erialal.The lack of interest in rowanberries has been caused by the specific astringent taste, which doesn`t allow to use them as raw fruit for eating. At the same time, rowanberries have been used in traditional medicine as a good source of vitamin C, anti-inflammatory and as diuretic drug.
Rowanberries have also been used to make juice, but the juice pressing residue hasn`t got a practical application. Detailed information on the composition and antioxidant properties of this promising natural source is important for the development of functional supplements from rowanberry pomace. Therefore, in this work, the antioxidant characteristics of the fruits, juice and pomace of 16 sweet rowanberry cultivars (cvs) and wild rowanberry were determined. Based on the above-mentioned characteristics, the pomace of cvs with good antioxidant potential and the highest polyphenol content were selected for further applied research. The selected materials were the pomaces of cvs 'Likernaja', 'Solnechnaja', 'Sahharnaja' and wild rowanberry.
A mixture of 'Likernaja', 'Solnechnaja' and wild rowan pomaces was used to prepare functional ingredients for pork meatballs. The metabolomics of the meatballs on the day 14 of storage, revealed that aldehydes and ketones, which indicate the meat spoilage, were present only in the control sample, as well as the content of linoleic acid derivatives had decreased only in the control sample, which indicated the oxidation of unsaturated fatty acids. Thus, it could be concluded that it is possible to inhibit the oxidation of meat products with rowanberry pomace based ingredients.Viimastel aastakümnetel on teadlaste ülesandeks katsetada ja kasutusele võtta üha uusi taimseid bioaktiivsete ühendite allikaid. Need ühendid pakuvad huvi nii tervise- kui ka toitumisspetsialistidele. Siiski on veel mitmeid siiani vähe uuritud puuvilju ja marju, mida oleks võimalik kasutada potentsiaalsete antioksüdantidena funktsionaalse toidu, kosmeetika või ravimite koostises. Samuti on teadlastele väljakutseks puuviljade ja marjade töötlemisel tekkivate kõrvalsaaduste väärindamine funktsionaalseteks komponentideks.
Vähene huvi pihlakate vastu on eelkõige olnud tingitud nende spetsiifilisest kootavast maitsest, mis ei võimalda pihlaka vilju kasutada nn. lauamarjadena. Samas on rahvameditsiinis pihlakaid kasutatud C-vitamiini allikana, diureetikumidena, kõhulahtisuse vastu, põletikuvastase ravimina jm. Samuti on pihlakaid kasutatud mahla ja veini valmistamiseks. Mahla valmistamisel tekib pressjääk, mida võiks kasutada bioaktiivsete ühendite allikana.
Pihlaka pressjäägist funktsionaalsete lisandite väljatöötamiseks on oluline üksikasjalik teave selle sortide koostise ja antioksüdantsete omaduste kohta. Seetõttu määrati käesolevas töös 16 saaki andva kultuurpihlaka sordi ja ühe looduslikult kasvava hariliku pihlaka viljade, mahla ja pressjäägi polüfenoolsete ühendite sisaldus ja vabade radikaalide sidumise võime. Eelmainitud karakteristikute põhjal valiti välja heade antioksüdatiivsete omadustega ja suurima polüfenoolide sisaldusega sortide pressjäägid edasisteks rakendusuuringuteks. Valituks osutusid 'Likernaja', 'Solnetšnaja', 'Sahharnaja' ja hariliku pihlaka pressjäägid.
'Likernaja', 'Solnetšnaja' ja hariliku pihlaka pressjääkide segu kasutati funktsionaalsete lisandite valmistamiseks sealihast hakklihapallidele. Esimene lisand (AC) saadi pressjääkide segu rasvatustamisel ülekriitilise CO2 ekstraktoris. Teise ja kolmanda lisandi jaoks võeti osa rasvatustatud pressjääki ja ekstraheeriti seda mikrolaineliselt etanooli lahusega. Peale ekstraktsiooni lahus filtreeriti ning filtratsiooni jääk ja supernatant lüofiliseeriti. Lüofiliseeritud jääki (R) ja ekstrakti (E) kasutati samuti lihapallide lisanditena. Lisanditega lihapalle hinnati sensoorselt ning valiti välja sobivaimaid lisandite kontsentratsioonid: 2%AC, 2% R ja 1% E. Kiudainerikkad AC ja R lisandid vähendasid lihapallide rasvasisaldust ning lisand R vähendas ligi 13% küpsetuskadu. Vaba radikaali (DPPH•) neutraliseerimise katses osutus 1%-E lihapallides kõige suurema antioksüdatiivsusega lisandiks. Lihapallide metaboloomika abil tuvastati, et liha riknemisel tekkivad aldehüüdid ja ketoonid, esinesid säilitamise 14. päeval ainult kontrollproovis, mitte aga lisanditega proovides. Samuti oli ainult kontrollproovis vähenenud linoolhappe dervaatide sisaldus, mis viitas küllastamata rasvhapete oksüdatsioonile. Seega võis järeldada, et pihlaka pressjäägi lisanditega on võimalik pärssida lihatoodete oksüdatsiooni.Publication of this thesis is supported by the Estonian University of Life Sciences
Comparative Evaluation of Topological and Demographic Features for Service Adoption Prediction
Käesoleva magistritöö sisu on konfidentsiaalneContents of this Master Thesis are confidentsia
Ideology behind ecological design
[Abstract] The aim of this article is to investigate the messages that are carried by ecological design. More precisely under review are ecological products and movements which advertise their usage. One of these movements is called «Bright Green Environmentalism» and its aim is to introduce already existing solutions to environmental problems. For this scope they have quite well known web-journal called «Worldchanging» which promotes the usage of ecological and sustainable products and they have published a book called «Worldchanging: a practical guide to 21 century». The message which this movement is communicating is that it is not necessary to renounce modern comforts and consumerism while being ecological. They believe that the solution to environmental problems can be found in sustainable design. The journal «Worldchanging» is supposed to be a combination of «socially conscious capitalism» and idealism. They declare that their approach is at the same time the one of activists and the consumerists. It is possible to analyze this interesting combination of ideas from the viewpoint of ideology. Italian semiotician Ferruccio Rossi-Landi has classified the conceptions of ideology under eleven headings. In this paper we are going to analyze the case of Bright Green Environmentalism and try to discover under which one of these eleven types of ideology we could place it. Below we are going to approach the phenomena of commercial green design from semioethic viewpoint. Semioethic theory suggests that human beings should be thought of not as «res cognitas» but as «semiotic animals» because humans hold immense responsibility towards the surrounding world as they are able to reflect over their actions, plan and suspend or change them. The ability of imagination that allows us to feel for the others puts us also in a position of no alibis. The scope of semioethics is to unmask the hidden ideologies that surround us and which we ourselves help to create
Does Information Technology Investment Influences Firm’s Market Value? The Case of Non-Publicly Traded Healthcare Firms
Managers make informed information technology investment decisions when they are able to quantify how IT contributes to firm performance. While financial accounting measures inform IT’s influence on retrospective firm performance, senior managers expect evidence of how IT influences prospective measures such as the firm’s market value. We examine the efficacy of IT’s influence on firm value combined with measures of financial performance for non-publicly traded (NPT) hospitals that lack conventional market-based measures. We gathered actual sale transactions for NPT hospitals in the United States to derive the q ratio, a measure of market value. Our findings indicate that the influence of IT investment on the firm is more pronounced and statistically significant on firm value than exclusively on the accounting performance measures. Specifically, we find that the impact of IT investment is not significant on return on assets (ROA) and operating income for the same set of hospitals. This research note contributes to research and practice by demonstrating that the overall impact of IT is better understood when accounting measures are complemented with the firm’s market value. Such market valuation is also critical in merger and acquisition decisions, an activity that is likely to accelerate in the healthcare industry. Our findings provide hospitals, as well as other NPT firms, with insights into the impact of IT investment and a pragmatic approach to demonstrating IT’s contribution to firm value
Poetic metre as a function of language: linguistic grounds for metrical variation in Estonian runosongs
The article focuses on the relationship of language and metre in case of oral poetry, more exactly, to what extent and through which processes the changes in language have induced the changes in metre in case of Estonian runosong, a branch of common Finnic poetic-musical tradition. The Estonian language has gone through a series of notable phonological changes during approximately last 500 to 700 years that have systematically shortened the word forms; the extent of these changes varies across dialects. At the same time the language of runosongs has partly resisted these changes, and partly adopted; the archaic and new word forms are in concurrent use, and vary geographically. The metre of Estonian runosongs appears to be a transitional form from quantitative runosong metre (Kalevala metre) to the accentual runosong metre (both of them syllabic metres). The current study shows that the transition depends directly on the average syllabic length of the words in runosongs (the longer the words, the more quantitative the metre, and vice versa), which in turn is induced by the shortening of words in dialectal language. The closer look at the points of tensions between the metre and language, i.e. the geographical distribution of the morphological forms that are critical for building the verses in quantitative metre and have been systematically retained in runosongs (but shortened in language) shows that in two metrically innovative areas runosongs have given up preserving the archaic word forms, while in big central area between a linguistically and metrically conservative centre in the North-East of Estonia and two innovation centres in Western and Southeastern Estonia the archaic and newer word forms are used concurrently. The slight difference between the metre of western and southeastern runosongs follows the prosodic patterns of dialectal language.
The side topic of the article discusses the questions of the evolution of runosong in the light of newer theories of emergence of Finnic languages (in the first millennium BC) and poetic system of runosongs, but apparently the metrical variation of runosong is entirely explicable by the impact of much later language changes (approximately 500 to 700 years ago) and seems not to be able to answer the questions related to the emergence of the poetic tradition
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