X-ray absorption spectroscopy study of diluted magnetic semiconductors: Zn1-xMxSe (M = Mn, Fe, Co) and Zn1-xMnxY (Y = Se, Te)

We have investigated 3d electronic states of doped transition metals in II-VI diluted magnetic semiconductors, Zn1-xMxSe (M = Mn, Fe, Co) and Zn1-xMnxY (Y = Se, Te), using the transition-metal L2,3-edge X-ray absorption spectroscopy (XAS) measurements. In order to explain the XAS spectra, we employed a tetragonal cluster model calculation, which includes not only the full ionic multiplet structure but also configuration interaction (CI). The results show that CI is essential to describe the experimental spectra adequately, indicating the strong hybridization between the transition metal 3d and the ligand p orbitals. In the study of Zn1-xMnxY (Y = Se, Te), we also found considerable spectral change in the Mn L2,3-edge XAS spectra for different ligands, confirming the importance of the hybridization effects in these materials.Comment: This paper consists of 22 pages including 4 figures. This paper is submitted to Physical Review

Evaluation of the level and way of using information technologies by students of the agricultural professional technical school based on survey

W pracy przedstawiono wyniki badania przeprowadzonego wśród uczniów 45 ponadgimnazjalnych szkół rolniczych nadzorowanych przez Ministra Rolnictwa i Rozwoju Wsi. Wyniki te umożliwiły określenie rozwoju społeczeństwa zamieszkującego obszary wiejskie i miejskie w zakresie uczestnictwa młodzieży w budowaniu i rozwoju społeczeństwa informacyjnego kraju w obszarze rolnictwa oraz wdrażania i wykorzystania nowych technologii i internetu w prowadzeniu gospodarstw rolnych. Badana młodzież może stanowić potencjalną grupę przyszłych producentów rolnych, a także może przyczynić się do wdrażania i wzrostu wykorzystywania nowych technologii w prowadzeniu gospodarstwa. Pomimo dużej dostępności technologii informacyjnych, zarówno na obszarach miejskich, jak i wiejskich, nadal można zauważyć stosunkowo małe zainteresowanie producentów rolnych programami komputerowymi przeznaczonymi dla rolnictwa.The paper presents the results of research conducted among students 45 post-secondary agricultural schools supervised by the Minister of Agriculture and Rural Development. The results to determine the development of the society residing in rural areas and urban youth participation in the construction and development of the information society of the country in the field of the agriculture and the implementation and use of new technologies, as well as the internet in running farms. Young people living in rural areas, a potential group of future agricultural producers and may also contribute to the implementation and growth of the use of new technologies in the conduct farm. Despite the large availability of information technologies, in both urban and rural areas, which may indicate a high level of computerization, still can be seen relatively little interest farmers of computer programs designed for agriculture

Opportunities for the development of organic farming system in the Świętokrzyskie Province

W okresie dynamicznie zwiększającej się liczby gospodarstw i przetwórni ekologicznych w Polsce, wyraźnie zarysowuje się potrzeba badań nad możliwością rozwoju tego systemu gospodarowania, jak również nad barierami, które ten rozwój hamują. Badania ankietowe prowadzono, w latach 2007-2009, w losowo wybranych 96 gospodarstwach ekologicznych w województwie świętokrzyskim. Uzyskane wyniki badań wskazują, że rolnicy, szczególnie ci bez wykształcenia rolniczego, od początku prowadzenia działalności ekologicznej nastawieni są głównie na pomoc finansową Unii Europejskiej, a nie na zyski z produkcji. Problemem jest też trudna organizacja zbytu towarów na rynku i brak promocji produktów. Niezbędna jest też przynależność do grupy producenckiej. Jednakże większość ankietowanych widzi jedynie trudność w założeniu i uczestnictwie w takich grupach. Rolnicy z wykształceniem rolniczym, prowadzący gospodarstwa towarowe, zwłaszcza warzywnicze i sadownicze, są w mniejszym stopniu zainteresowani pomocą doradców rolnych. Najprawdopodobniej wynika to ze słabo jeszcze wykształconego doradztwa specjalistycznego w zakresie rolnictwa ekologicznego.In the rapidly growing number of organic farms and processing plants in Poland, there is a need for research of the opportunities for development of this management system as well as the barriers that hamper development. This survey was carried out in 2007-2009 in 96 randomly selected organic farms in the Świętokrzyskie Province. The results indicate that when farmers begin the conversion into organic production, especially those with no agricultural education, depend mainly on the financial assistance from the European Union and not on the profits from production. The next problem lies with difficulties in the organization of selling yields on the market and a lack of product promotion. It is also essential to be affiliated with a group of producers, however most producers have difficulties seeing the benefits of participation in such groups. Farmers with agricultural education who lead selling, especially of fruit and vegetables, are less concerned with agricultural advisers. This is most likely due to the poor education of specialist advisers in organic farming

Electromagnetic Field Computation for Power Transmission Lines Using Quasi-Static Sub-Gridding Finite-Difference Time-Domain Approach

A new approach to the modeling of electromagnetic wave propagation and penetration in and around electrically small objects is presented. The traveling electromagnetic wave from a source is simulated by the finite-difference time-domain solution of Maxwell's equations, and a sub-gridding technique is imposed at points of interest in order to observe the electromagnetic field at high resolution. The computational burden caused by the requirement for a large number of time steps has been ameliorated by implementing the state-of-the-art quasi-static approach. The method is demonstrated by finding the induced electromagnetic fields near a buried pipeline that runs parallel to 400-kV power transmission lines; results are presented and discussed

A review of location based services:Current developments, trends and issues

Location based services are a diverse and growing set of related technologies which may be used to provide tracking and location awareness. LBS are employed in both fixed and mobile networks. A concise overview of the development of LBS, and some of the operational issues is presented. Seen from the physical layer, LBS are constrained by multipath interference, low signal to noise power, and channel fading. LBS methodologies including cell-ID, prediction (dead-reckoning), angle of arrival (AOA), time of arrival (TOA) and observed time difference of arrival (TDOA), hybrid AOA-TOA localization and localization by finger printing are summarised. There are two principal areas of constraint to be addressed, (1) in the service segment, practical and legal issues related to the subscriber privacy require development and clarification; and (2) the ability to deliver real time data, and measure the associated mobility of a subscriber (or target) with the required level of precision

Current technologies and location based services

This paper examines the benefits and drawbacks of these services, reviewing differences in infrastructure, power requirements, sensing devices, and other factors. Technologies covered include Radio Frequency Identification, GSM, GPS, A-GPS, Smart Antennas, Distributed Antenna Systems, Localization by Cell-ID, Localization by Prediction (Dead Reckoning method), Angle of Arrival (AOA), Localization by Finger Printing, Localization by Time of Arrival (TOA), Localization by Observed Time Difference of Arrival (TDOA), and Hybrid Localization-based AOA-TOA