888 resultados para Lejins, Atis: Small states in a turbulent environment


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Decision making and technical decision analysis demand computer-aided techniques and therefore more and more support by formal techniques. In recent years fuzzy decision analysis and related techniques gained importance as an efficient method for planning and optimization applications in fields like production planning, financial and economical modeling and forecasting or classification. It is also known, that the hierarchical modeling of the situation is one of the most popular modeling method. It is shown, how to use the fuzzy hierarchical model in complex with other methods of Multiple Criteria Decision Making. We propose a novel approach to overcome the inherent limitations of Hierarchical Methods by exploiting multiple criteria decision making.

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Full text: Semiconductor quantum dot lasers are attractive for multipletechnological applications in biophotonics. Simultaneous two-state lasing ofground state (GS) and excited state (ES) electrons and holes in QD lasers ispossible under a certain parameter range. It has already been investigated in steady-stateoperations and in dynamical regimes and is currently a subject of the intesiveresearch. It has been shown that the relaxation frequency in the two-state lasingregime is not a function of the total intensity [1], as could be traditionallyexpected.In this work we study damping relaxation oscillations in QD lasersimultaneously operating at two transitions, and find that under variouspumping conditions, the frequency of oscillations may decrease, increase orstay without change in time as shown in Fig1.The studied QD laser structure wasgrown on a GaAs substrate by molecular-beam epitaxy. The active region includedfive layers of self-assembled InAs QDs separated with a GaAs spacer from a5.3nm thick covering layer of InGaAs and processed into 4mm-wide mesa stripe devices. The 2.5mm long lasers withhigh-and antireflection coatings on the rear and front facets lasesimultaneously at the GS (around 1265nm) and ES (around 1190nm) in the wholerange of pumping. Pulsed electrical pumping obtained from a high power (up to2A current) pulse source was used to achieve high output power operation. We simultaneously detect the total output and merely ES output using aBragg filter transmitting the short-wavelength and reflecting the long-wavelengthradiation. Typical QD does not demonstrate relaxation oscillations frequencybecause of the strong damping [2]. It is confirmed for the low (I<0.68A) andhigh (I>1.2 A) range of the pump currents in our experiments. The situationis different for a short range of the medium currents (0.68Aincrease (from 2 GHz to 4 GHz)within 20 ns of the pulse duration. The oscilations appear simultaneously at GSand ES and are always damped, but can be either inphase or antiphase dependingon the pump current and temperature conditions. We address the excitation of the relaxation oscillations to non-instantaneousturn on of the pumping source which activates with 5ns rise time and discussthe swap of the oscillation's frequency in time to spectral shifts caused by thermaleffects. [1] M.Abusaa, J. Danckaert, E. A. Viktorov, and T. Erneux, Phys. Rev. A 87, 063827(2013). [2] T.Erneux, E. A. Viktorov, and P. Mandel, Phys. Rev. A 76,023819 (2007). 1 © 2014 IEEE.

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2000 Mathematics Subject Classification: 60J80, 60K05.

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OBJECTIVE: To analyze, in a general population sample, clustering of delusional and hallucinatory experiences in relation to environmental exposures and clinical parameters. METHOD: General population-based household surveys of randomly selected adults between 18 and 65 years of age were carried out. SETTING: 52 countries participating in the World Health Organization's World Health Survey were included. PARTICIPANTS: 225 842 subjects (55.6% women), from nationally representative samples, with an individual response rate of 98.5% within households participated. RESULTS: Compared with isolated delusions and hallucinations, co-occurrence of the two phenomena was associated with poorer outcome including worse general health and functioning status (OR = 0.93; 95% CI: 0.92-0.93), greater severity of symptoms (OR = 2.5 95% CI: 2.0-3.0), higher probability of lifetime diagnosis of psychotic disorder (OR = 12.9; 95% CI: 11.5-14.4), lifetime treatment for psychotic disorder (OR = 19.7; 95% CI: 17.3-22.5), and depression during the last 12 months (OR = 11.6; 95% CI: 10.9-12.4). Co-occurrence was also associated with adversity and hearing problems (OR = 2.0; 95% CI: 1.8-2.3). CONCLUSION: The results suggest that the co-occurrence of hallucinations and delusions in populations is not random but instead can be seen, compared with either phenomenon in isolation, as the result of more etiologic loading leading to a more severe clinical state.

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The Analytic Hierarchy Process (AHP) is one of the most popular methods used in Multi-Attribute Decision Making. It provides with ratio-scale measurements of the prioirities of elements on the various leveles of a hierarchy. These priorities are obtained through the pairwise comparisons of elements on one level with reference to each element on the immediate higher level. The Eigenvector Method (EM) and some distance minimizing methods such as the Least Squares Method (LSM), Logarithmic Least Squares Method (LLSM), Weighted Least Squares Method (WLSM) and Chi Squares Method (X2M) are of the tools for computing the priorities of the alternatives. This paper studies a method for generating all the solutions of the LSM problems for 3 × 3 matrices. We observe non-uniqueness and rank reversals by presenting numerical results.

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The study uses the value test developed by Shalom Schwartz to examine the value system of Hungarian entrepreneurs. First, the dataset of the last wave of the European Social Survey is used to define those value orientations which generally distinguish entrepreneurs from the rest of society in Europe. Second, the prevalence of these ‘entrepreneurial values’ in the general populations of various countries, and Hungary in particular, is explored. Third, using compatible data from a survey of 300 Hungarian small entrepreneurs, the value orientations that distinguish them from other European entrepreneurs and Hungarian non-entrepreneurs are examined. Multivariate regression analyses allow us to draw a nuanced value-portrait of the typical Hungarian entrepreneur. The main conclusion is that although Hungarian small entrepreneurs share the ’core values’ of entrepreneurs in Europe, they are less adventurous and less materialist, but held personal freedom and human relations especially dear.

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A cikk legfontosabb megválaszolandó kérdése: Milyen esélyekkel és milyen szükséges lépésekkel indulhatnak a nemzetközileg kevéssé ismert hazai célállomások és vállalkozásaik a turisztikai piac globális versenyében, melynek egyre jelentősebb színterét az internet adja? A turisztikai piacon az internet piacalakító hatása és az individualista, élmény, és értékközpontú kereslet megjelenése olyan változásokat indított el az elmúlt közel húsz évben, melyek befolyásolva a szereplők erőviszonyait a fejlődés lehetőségét hordozzák a regionális célállomások, a kevéssé ismert desztinációk számára. Mindezen trendek egyúttal kihívást jelentenek, mivel élesítik a versenyt, és megújulásra ösztönzik a globálisan ismert desztinációkat is, valamint számos nehézség megoldására késztetik a több szempontból hátrányban szenvedő vidéki régiókat. A cikkben ismertetendő kutatás célja az, hogy egy best practice-ként ismert osztrák és három hazai eset alapján felderítse azon tényezőket, melyek a desztinációfejlesztés kezdeti lépésétől az e-business sikeres adaptációjához, a desztinációmenedzsment-rendszerek bevezetéséhez és működtetéséhez vezetnek. __________ The main question of the paper: What kind of steps should the Hungarian less-known destinations take to meet the challenges of the global competition increasingly taking place on the internet? The trends of “new tourism” – driven by post-materialistic values –, and the growing role of internet in touristy activity have formed new conditions and changed the balance of forces in the touristy market. These two trends hand in hand have intensified the competition: on the one hand force global destinations to renew, on the other hand give great but challenging possibilities for regional destinations in comparative disadvantage. The aim of the paper is to identify the success-factors of adopting e-business solution called destination management system in the regional, undeveloped areas starting destination management from zero position. For this purpose case studies were examined by analyzing Hungarian regional destinations’ development and making a benchmark analysis through an Austrian best practice.

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Az itt bemutatott kutatás célja az volt, hogy azonosítsa és feltárja a szlovák vállalati környezetben követett és kívánatosnak tartott leadership dimenziókat és bemutassa azokat az implicit leadership elmélet alapján meghatározott magatartásokat, amelyek a sikeres leadershipet támogató magatartásokként jelennek meg (az implicit leadership elmélet szerint az egyének magatartásokhoz kapcsolódó hiedelmeik, meggyőződéseik és értékítéleteik alapján határozzák meg, kit tekintenek vezetőnek, illetve hogyan különböztetik meg a hatékony vezetést a nem hatékonytól). Ehhez a GLOBE (Global Leadership and Organization Behavior Effectiveness) kutatását használta fel a szerző empirikus alapként. A faktorelemzéssel előállított kutatási eredmények azt bizonyítják, hogy definiálhatók a nemzetközi mintán elkülöníthető implicit leadership elméletektől jól megkülönböztethető szlovák implicit leadership elméletek. Statisztikai próbáinak eredményei azt mutatják, hogy léteznek olyan leadership faktorok, melyek a szlovák és a magyar vállalati környezetben is megjelennek, illetve feltárhatók olyan implicit leadership elméletek, melyek megítélése ebben a régióban egységesnek tekinthető. _____ The aim of this research is to identify and explore the committed and desirable leadership dimensions in the Slovak organizational environment. This article presents those on the basis of implicit leadership theories identified behaviors which appear as successful leadership supported behaviors. To it the GLOBE (Global Leadership and Organization Behavior Effectiveness) research is used as the empirical basis by the author. Research results which were produced by factor analysis demonstrate that the Slovak implicit leadership theories can be identified because those can be clearly distinguished from implicit leadership theories available in the international sample.

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Néhány éve vonult be a köztudatba a cloud computing fogalom, mely ma már a szakirodalomban és az informatikai alkalmazásokban is egyre nagyobb teret foglal el. Ez az új IT-technológia a számítási felhő számítástechnikai szolgáltatásaihoz kapcsolódó ERP-rendszerek szabványosítását, elterjedését eredményezi. A szerzők cikkükben áttekintést adnak a cloud computing mai helyzetéről és a számítási felhőben működő adatfeldolgozó rendszerekkel (kiemelten ERP) kapcsolatos felhasználói elvárásokról, illetve kezdeti, németországi alkalmazási tapasztalatokról. Külön tárgyalják az ERP-rendszerek új kiválasztási céljait és kritériumait, melyek a felhőkörnyezet speciális lehetőségei miatt alakultak ki. _____ The concept of ‘Cloud’ as an IT notion emerged in the past years and proliferated within the business and IT professional community. The concept of cloud gained awareness both in the professional and scientific literature and in the practice of IT/IS world. The cloud has a profound impact on the Business Information Systems, especially on ERP systems. Indirectly, the cloud leads to a massive standardization on ERP systems and their services. In this paper, the authors provide a literature overview about the current situation of Cloud Computing and the requirements established by end-users against the other data processing facilities and systems, outstandingly the ERP systems. The majority of investigated cases are based on samples from Germany. Furthermore, the initial experiences of application are discussed. Separately, the recent selection objectives and criteria for ERP systems are investigated that came into existence because the appearance of Cloud in the IT environment.

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Mercury (Hg) contamination problem in the United Sates has been an important issue due to its potential threat to human and ecological health. This thesis presents a study of two Hg-contaminated sites along the East Fork Poplar Creek (EFPC) at Oak Ridge. The top soils from the terrestrial areas, along with the soils from three vertical soil horizons at the EFPC bank were sampled and analyzed for total-Hg (THg), methyl-Hg, total-organic-carbon (TOC), and pH. The stream bank soils were also analyzed for the stable-Hg-isotopes (198Hg, 199Hg, 200Hg, 201Hg, and 202Hg). Furthermore, some of the soil samples (n=7) from the same study sites were investigated for phytoavailability of mercury as measured by degree of Hg translocation in aboveground biomass of Impatiens walleriana plants grown in the soils.^ The results showed a significant difference (p<0.001) in THg concentrations for the forest soils (42.40±4.98 mg/kg) and the grassland soils (8.71±2.30 mg/kg). The higher THg and methyl-Hg concentrations were commensurate with the higher TOC content in the soils (p<0.001). Also, the THg concentrations for the upstream site was higher (129.08±34.14 mg/kg) than the downstream site (24.31±3.47 mg/kg). The two sites also differed in their stable Hg isotope compositions (p<0.001 for δ199Hg). The stable isotope analysis indicated the increased level of mass dependent isotopic fractionation with increasing depths along the EFPC bank. The difference between the two study sites was also prominent in case of the Hg uptake by the plants, with higher Hg uptake from the upstream soils compared to that from the downstream soils. A significant correlation, r=0.93 p<0.01, was observed between the Hg uptake and the soil-THg concentrations. THg was higher in the leaves (1161.87±310.01 μg/kg) than in the flowers (206.13±55.23 μg/kg) or the stems (634.54±403.35μg/kg). ^ The level of Hg contamination increased with decreasing distance from the point source and was highly influenced by plants/microbes, soil-organic-content, and Hg-speciation. The isotopic study indicated the existence of an additional Hg source in the EFPC watershed, possibly atmospheric Hg-deposition. These findings are worth taking into account while planning any Hg remediation effort and developing Hg loading criteria as per the National Pollutant Discharge Elimination System (NPDES) Program.^

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Since the arrival of the first African slaves to Cuba in 1524, the issue of race has had a long-lived presence in the Cuban national discourse. However, despite Cuba’s colonial history, it has often been maintained by some historians that race relations in Cuba were congenial with racism and racial discrimination never existing as deep or widespread in Cuba as in the United States (Cannon, 1983, p. 113). In fact, it has been argued that institutionalized racism was introduced into Cuban society with the first U.S. occupation, during 1898–1902 (Cannon, 1983, p. 113). This study of Cuba investigates the influence of the United States on the development of race relations and racial perceptions in post-independent Cuba, specifically from 1898-1902. These years comprise the time period immediately following the final fight for Cuban Independence, culminating with the Cuban-Spanish-American War and the first U.S. occupation of Cuba. By this time, the Cuban population comprised Africans as well as descendants of Africans, White Spanish people, indigenous Cubans, and offspring of the intermixing of the groups. This research studies whether the United States’ own race relations and racial perceptions influenced the initial conflicting race relations and racial perceptions in early and post-U.S. occupation Cuba. This study uses a collective interpretative framework that incorporates a national level of analysis with a race relations and racial perceptions focus. This framework reaches beyond the traditionally utilized perspectives when interpreting the impact of the United States during and following its intervention in Cuba. Attention is given to the role of the existing social, political climate within the United States as a driving influence of the United Statesinvolvement with Cuba. This study reveals that emphasis on the role of the United States as critical to the development of Cuba’s race relations and racial perceptions is credible given the extensive involvement of the U.S. in the building of the early Cuban Republic and U.S. structures serving as models for reconstruction. U.S. government formation in Cuba aligned with a governing system reflecting the existing governing codes of the U.S. during that time period.

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Patterns of relative nutrient availability in south Florida suggest spatial differences regarding the importance of nitrogen (N) and phosphorus (P) to benthic primary producers. We did a 14-month in situ fertilization experiment to test predictions of N and P limitation in the subtropical nearshore marine waters of the upper Florida Keys. Six sites were divided into two groups (nearshore, offshore) representing the endpoints of an N: P stoichiometric gradient. Twenty-four plots were established at each site with six replicates of each treatment (1N, 1P, 1N1P, control), for a total of 144 experimental plots. The responses of benthic communities to N and P enrichment varied appreciably between nearshore and offshore habitats. Offshore seagrass beds were strongly limited by nitrogen, and nearshore beds were affected by nitrogen and phosphorus. Nutrient addition at offshore sites increased the length and aboveground standing crop of the two seagrasses, Thalassia testudinum and Syringodium filiforme, and growth rates of T. testudinum. Nutrient addition at nearshore sites increased the relative abundance of macroalgae, epiphytes, and sediment microalgae. N limitation of seagrass in this carbonate system was clearly demonstrated. However, added phosphorus was retained in the system more effectively than N, suggesting that phosphorus might have important long-term effects on these benthic communities. The observed species-specific responses to nutrient enrichment underscores the need to monitor all primary producers when addressing questions of nutrient limitation and eutrophication in seagrass communities.

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Amidst concerns about achieving high levels of technology to remain competitive in the global market without compromising economic development, national economies are experiencing a high demand for human capital. As higher education is assumed to be the main source of human capital, this analysis focused on a more specific and less explored area of the generally accepted idea that higher education contributes to economic growth. The purpose of this study, therefore, was to find whether higher education also contributes to economic development, and whether that contribution is more substantial in a globalized context. ^ Consequently, a multiple linear regression analysis was conducted to support with statistical significance the answer to the research question: Does higher education contributes to economic development in the context of globalization? The information analyzed was obtained from historical data of 91 selected countries, and the period of time of the study was 10 years (1990–2000). Some variables, however, were lagged back 5, 10 or 15 years along a 15-year timeframe (1975–1990). The resulting comparative static model was based on the Cobb-Douglas production function and the Solow model to specify economic growth as a function of physical capital, labor, technology, and productivity. Then, formal education, economic development, and globalization were added to the equation. ^ The findings of this study supported the assumption that the independent contribution of the changes in higher education completion and globalization to changes in economic growth is more substantial than the contribution of their interaction. The results also suggested that changes in higher and secondary education completion contribute much more to changes in economic growth in less developed countries than in their more developed counterparts. ^ As a conclusion, based on the results of this study, I proposed the implementation of public policy in less developed countries to promote and expand adequate secondary and higher education systems with the purpose of helping in the achievement of economic development. I also recommended further research efforts on this topic to emphasize the contribution of education to the economy, mainly in less developed countries. ^