636 research outputs found
Small-angle scattering on a system of magnetic and electric charges
The generalization of the conformal scattering method for small-angle
scattering processes involving magnetic monopoles and ordinary charges is
constructed. Using this generalization we show that introducing of magnetic
charges corresponds to analytical continuation of the eikonal amplitude in the
complex charge plane (the imaginary part is proportional to the magnetic
charge). We calculate explicitly the eikonal amplitude for scattering on a dyon
and two monopoles in terms of confluent hypergeometric functions. The
singularities of the corresponding amplitudes (focal points) are studied in
details.Comment: 15 pages. 3 figures. Latex with epsf.sty use
DVCS amplitude in the parton model
We compute amplitude of deeply virtual Compton scattering in the parton
model. We found that the amplitude up to the accuracy O(1/Q) depends on new
skewed parton distributions (SPD's). These additional contributions make the
DVCS amplitude explicitly transverse.Comment: New spin sum rules for twist-3 SPD's are added. Discussion of 1/Q
behaviour of twist-3 contributions is correcte
The Language Awareness of Finnish and German EFL Senior High School Learners and Student Teachers Regarding English Grammar and Its Teaching
The aim of this study is to examine and contrast the language awareness of Finnish and German EFL senior high school students and student teachers regarding aspects of English grammar and its teaching. Data was collected from Finland and Germany during the academic school years of 2015–16 and 2016–17. It consists of the responses to twosurvey questions of 1st year EFL senior high school students (n = 200 from Finland, n = 200 from Germany) andstudent teachers (n = 118 from Finland, n = 118 from Germany). The study utilizes both qualitative (content analysis) and quantitative (frequencies, percentages, cross tabulation [χ2-test]) research methods. The results show that the subjects’ awareness of English grammar and its teaching was mainly based on intuitive, implicit knowledge. It was difficult for both senior high school learners and student teachers to build a cognitive understanding that would increase their awareness of English grammar, and, as a result of this, its teaching, and respectively their grammar-related didactical competences.The aim of this study is to examine and contrast the language awareness of Finnish and German EFL senior high school students and student teachers regarding aspects of English grammar and its teaching. Data was collected from Finland and Germany during the academic school years of 2015–16 and 2016–17. It consists of the responses to two survey questions of 1st year EFL senior high school students (n = 200 from Finland, n = 200 from Germany) and student teachers (n = 118 from Finland, n = 118 from Germany). The study utilizes both qualitative (content analysis) and quantitative (frequencies, percentages, cross tabulation [χ2-test]) research methods. The results show that the subjects’ awareness of English grammar and its teaching was mainly based on intuitive, implicit knowledge. It was difficult for both senior high school learners and student teachers to build a cognitive understanding that would increase their awareness of English grammar, and, as a result of this, its teaching, and respectively their grammar-related didactical competences.Peer reviewe
Lastauksen ja kuljetuksen resurssien optimointi
Tiivistelmä. Lastaus ja kuljetus ovat yksiä tärkeimpiä kaivoksen toimintoja ja niillä on suuri vaikutus kaivoksen tuotantoon ja kannattavuuteen. Lastaus- ja kuljetusoperaatiot ovat tärkeää pitää tehokkaana ja myös käytössä olevat lastauksen- ja kuljetuksen resurssit olisivat hyvä pitää tehokkaassa käytössä. Kaivosolosuhteissa tämä ei ole kuitenkaan helppoa ja resurssit ovat usein vaikea saada tehokkaaseen käyttöön.
Työn tarkoituksena on saada Kevitsan kaivoksen lastauksen- ja kuljetuksenresurssit tehokkaampaan käyttöön ja näin saataisiin myös kaluston alhaiset käyttöasteet kohoamaan. Työn alussa pyritään selvittämään ja tutkimaan eri vaihtoehtoja ja tapoja, joilla resurssit saataisiin tehokkaampaan käyttöön. Tutkimuksissa pyritään myös hyödyntämään teoriaa lastauksesta ja kuljetuksesta ja käyttöasteen parantamisesta.
Työssä Kevitsan kaivoksella ja lastauksen ja kuljetuksen mukana vietetään useita päiviä, jotta prosessi tulisi tutuksi ja ongelmakohdat avautuisivat paremmin. Työn aikana suoritettiin vierailu myös Ruotsiin Aitikin kaivokselle ja tutustuttiin heidän menetelmiinsä ja kokemuksiinsa liittyen lastaukseen ja kuljetukseen. Tutkimusten ja Kevitsan nykytilanteen pohjalta työssä aletaan kehitellä erilaisia vuorojärjestelmiä ja lisävuoroja lastaukseen ja kuljetukseen.
Työssä tarjotaan useita vuorojärjestelmä vaihtoehtoja lastauksen- ja kuljetuksenresurssien optimointiin. Vaihtoehtoja analysoidaan useilla eri kaivokselle merkityksellisillä tuloksilla. Sen jälkeen pohditaan niiden sopivuutta Kevitsan kaivoksen lastaukselle ja kuljetukselle ja vallitseviin olosuhteisiin.Optimization of loading and hauling resources. Abstract. Loading and transportation are one of the most important functions of the mine and have a great impact on the production and profitability of the mine. It is important to keep loading and transport operations efficient, and it would also be good to keep the available loading and transport resources in efficient use. In mining conditions, however, this is not easy and resources are often difficult to use effectively.
The purpose of the work is to get the loading and transportation resources of the Kevitsa mine to be used more efficiently, and in this way the low utilization rates of the equipment would also be increased. At the beginning of the work, the aim is to find out and investigate different options and ways to use the resources more efficiently. The research also aims to utilize the theory of loading and transportation and improving utilization.
Several days are spent at the Kevitsa mine, along with loading and transportation, so that the process becomes familiar and the problem areas are better revealed. During the work, a visit was also made to the Aitik mine in Sweden and we got to know their methods and experiences related to loading and transportation. Based on the research and Kevitsa’s current situation, the work begins to develop different shift systems and additional shifts for loading and transportation.
The work offers several different options for optimizing loading and transport resources. Alternatives are analyzed with several different results relevant to the mine. After that, we will consider their suitability for loading and transporting the Kevitsa mine and the prevailing condition
DVCS on the nucleon : study of the twist-3 effects
We estimate the size of the twist-3 effects on deeply virtual Compton
scattering (DVCS) observables, in the Wandzura-Wilczek approximation. We
present results in the valence region for the DVCS cross sections, charge
asymmetries and single spin asymmetries, to twist-3 accuracy.Comment: 20 pages, 6 figure
Kinematical twist-3 effects in DVCS as a quark spin rotation
We point out that the kinematical twist-3 contributions to the DVCS
amplitude, required to restore electromagnetic gauge invariance of the twist-2
amplitude up to O(t/q^2), can be understood as a spin rotation applied to the
twist-2 quark density matrix in the target. This allows for a compact
representation of the twist-3 effects, as well as for a simple physical
interpretation.Comment: 4 pages, revtex, 3 eps figures included using eps
Implications of processing spatial data from a forested catchment for a hillslope hydrological model
An uptake and elimination kinetics approach to assess the bioavailability of chromium, copper, and arsenic to earthworms (Eisenia andrei) in contaminated field soils
The aim of this study was to determine the bioavailability of metals in field soils contaminated with chromated copper arsenate (CCA) mixtures. The uptake and elimination kinetics of chromium, copper, and arsenic were assessed in the earthworm Eisenia andrei exposed to soils from a gradient of CCA wood preservative contamination near Hartola, Finland. In soils contaminated with 1480–1590 mg Cr/kg dry soil, 642–791 mg Cu/kg dry soil, and 850–2810 mg Ag/kg dry soil, uptake and elimination kinetics patterns were similar for Cr and Cu. Both metals were rapidly taken up and rapidly excreted by Eisenia andrei with equilibrium reached within 1 day. The metalloid As, however, showed very slow uptake and elimination in the earthworms and body concentrations did not reach equilibrium within 21 days. Bioaccumulation factors (BAF) were low for Cu and Cr (Peer reviewe
Assessment of human influenza pandemic scenarios in Europe
The response to the emergence of the 2009 influenza A(H1N1) pandemic was the result of a decade of pandemic planning, largely centred on the threat of an avian influenza A(H5N1) pandemic. Based on a literature review, this study aims to define a set of new pandemic scenarios that could be used in case of a future influenza pandemic. A total of 338 documents were identified using a searching strategy based on seven combinations of keywords. Eighty-three of these documents provided useful information on the 13 virus-related and health-system-related parameters initially considered for describing scenarios. Among these, four parameters were finally selected (clinical attack rate, case fatality rate, hospital admission rate, and intensive care admission rate) and four different levels of severity for each of them were set. The definition of six most likely scenarios results from the combination of four different levels of severity of the four final parameters (256 possible scenarios). Although it has some limitations, this approach allows for more flexible scenarios and hence it is far from the classic scenarios structure used for pandemic plans until 2009
Toxicity of binary mixtures of Cu, Cr and As to the earthworm Eisenia andrei
Chromated copper arsenate (CCA) mixtures were used in the past for wood preservation, leading to large scale soil contamination. This study aimed at contributing to the risk assessment of CCA-contaminated soils by assessing the toxicity of binary mixtures of copper, chromium and arsenic to the earthwormEisenia andreiin OECD artificial soil. Mixture effects were related to reference models of Concentration Addition (CA) and Independent Action (IA) using the MIXTOX model, with effects being related to total and available (H2O and 0.01 M CaCl(2)extractable) concentrations in the soil. Since only in mixtures with arsenic dose-related mortality occurred (LC(50)92.5 mg/kg dry soil), it was not possible to analyze the mixture effects on earthworm survival with the MIXTOX model. EC(50)s for effects of Cu, Cr and As on earthworm reproduction, based on total soil concentrations, were 154, 449 and 9.1 mg/kg dry soil, respectively. Effects of mixtures were mainly antagonistic when related to the CA model but additive related to the IA model. This was the case when mixture effects were based on total and H2O-extractable concentrations; when based on CaCl2-extractable concentrations effects mainly were additive related to the CA model except for the Cr-As mixture which acted antagonistically. These results suggest that the CCA components do interact leading to a reduced toxicity when present in a mixture.Peer reviewe
- …