A számítási felhő az Európai Unió egén (Cloud computing on the sky of European Union)

Napjaink informatikai világának talán legkeresettebb hívó szava a cloud computing, vagy magyar fordításban, a számítási felhő. A fordítás forrása az EU-s (Digitális Menetrend magyar változata, 2010) A számítási felhő üzleti modelljének részletes leírását adja (Bőgel, 2009). Bőgel György ismerteti az új, közműszerű informatikai szolgáltatás kialakulását és gazdasági előnyeit, nagy jövőt jósolva a számítási felhőnek az üzleti modellek versenyében. A szerző – a számítási felhő üzleti előnyei mellett – nagyobb hangsúlyt fektet dolgozatában a gyors elterjedést gátló tényezőkre, és arra, hogy mit jelentenek az előnyök és a hátrányok egy üzleti, informatikai vagy megfelelőségi vezető számára. Nem csökkentve a cloud modell gazdasági jelentőségét, fontosnak tartja, hogy a problémákról és a kockázatokról is szóljon. Kiemeli, hogy a kockázatokban – különösen a biztonsági és adatvédelmi kockázatokban – lényeges különbségek vannak az Európai Gazdasági Térség és a világ többi része, pl. az Amerikai Egyesült Államok között. A cikkben rámutat ezekre a különbségekre, és az olvasó magyarázatot kap arra is, hogy miért várható a számítási felhő lassabb terjedése Európában, mint a világ más részein. Bemutatja az EU erőfeszítéseit is a számítási felhő európai terjedésének elősegítésére, tekintettel a modell versenyképességet növelő hatására. / === / One of the most popular concept of the recent web searches is cloud computing. Several authors present detailed description of the new service model and it's business benefits and cite the optimistic prognoses of the cloud experts regarding the competition of information system service models. The author analyses the operational benefits of the cloud application and give a detailed description of the inhibitors of the fast expansion of the service modell. He also analyses the pros and cons of the cloud for a business manager, an information and a compliance officer. When understanding the advantages of the cloud, it is equally important to review the problems and risks associated with the model. The paper gives a list of the expected cloud-specific risks. It also explains the differences in security and data protection approach between the European Economic Area and the rest of the world, including the USA. The explains why slower expansion of the cloud modell is expected in Europe than in the rest of the world. The efforts of the EU Committee in helping to spread the cloud model is also presented, as the EU's officers consider the model as an important element of competitiveness

Informatika, telekommunikáció és gazdasági stabilitás (Information technology, telecommunications and economic stability)

Fizikai példákon és matematikai modelleken bemutatjuk, hogy a rendszerek működésének hatékonyságnövekedése instabilitást eredményezhet. Megvizsgáljuk, hogy az informatika és a telekommunikáció fejlődése okozhat-e rendszerszintű instabilitást, illetve milyen gazdasági eszközök vannak a stabilitás fenntartására. / === / Using examples from physics and mathematical modeling, the paper shows that increasing efficiency in systems can lead to instability. The question thus arises whether the development of information and telecommunication technology can lead to instability in the economic system. The policy tools used to maintain stability are also discussed

Geometrical and physical interpretation of the Levi-Civita spacetime in terms of the Komar mass density

We revisit the interpretation of the cylindrically symmetric, static vacuum Levi-Civita metric, known in either Weyl, Einstein-Rosen, or Kasner-like coordinates. Despite the infinite axis source, we derive its Komar mass density through a compactification and subsequent blowing up of the compactification radius. We show that, the Komar mass density $\mu_K$ calculated in the Einstein-Rosen frame, when employed as the metric parameter, has a number of advantages. It eliminates double coverages of the parameter space, vanishes in flat spacetime and when small, it corresponds to the mass density of an infinite string. After a comprehensive analysis of the local and global geometry, we proceed with the physical interpretation of the Levi-Civita spacetime. First we show that the Newtonian gravitational force is attractive and its magnitude increases monotonically with all positive ${\mu}_K$, asymptoting to the inverse of the the proper distance in the "radial" direction. Second, we reveal that the tidal force between nearby geodesics (hence gravity in the Einsteinian sense) attains a maximum at $\mu_K=1/2$ and then decreases asymptotically to zero. Hence, from a physical point of view the Komar mass density of the Levi-Civita spacetime encompasses two contributions: Newtonian gravity and acceleration effects. An increase in $\mu_K$ strengthens Newtonian gravity but also drags the field lines increasingly parallel, eventually transforming Newtonian gravity through the equivalence principle into a pure acceleration field and the Levi-Civita spacetime into a flat Rindler-like spacetime. In a geometric picture the increase of $\mu_K$ from zero to $\infty$ deforms the planar sections of the spacetime into ever deepening funnels, eventually degenerating into cylindrical topology.Comment: 16 pages, 8 figure

Geometrical and physical interpretation of the Levi-Civita spacetime in terms of the Komar mass density

We revisit the interpretation of the cylindrically symmetric, static vacuum Levi-Civita metric, known in either Weyl, Einstein–Rosen, or Kasner-like coordinates. The Komar mass density of the infinite axis source arises through a suitable compactification procedure. The Komar mass density \mu _{K} μ K calculated in Einstein–Rosen coordinates, when employed as the metric parameter, leads to a number of advantages. It eliminates double coverages of the parameter space, vanishes in flat spacetime and when small, it corresponds to the mass density of an infinite string. After a comprehensive analysis of the local and global geometry, we proceed with the physical interpretation of the Levi-Civita spacetime. First we show that the Newtonian gravitational force is attractive and its magnitude increases monotonically with all positive \mu _{K} μ K , asymptoting to the inverse of the proper distance in the radial direction. Second, we reveal that the tidal force between nearby geodesics (hence gravity in the Einsteinian sense) attains a maximum at \mu _{K}=1/2 μ K = 1 / 2 and then decreases asymptotically to zero. Hence, from a physical point of view the Komar mass density of the Levi-Civita spacetime encompasses two contributions: Newtonian gravity and acceleration effects. An increase in \mu _{K} μ K strengthens Newtonian gravity but also drags the field lines increasingly parallel, eventually transforming Newtonian gravity through the equivalence principle into a pure acceleration field and the Levi-Civita spacetime into a flat Rindler-like spacetime. In a geometric picture the increase of \mu _{K} μ K from zero to \infty ∞ deforms the planar sections of the spacetime into ever deepening funnels, eventually degenerating into cylindrical topology in an appropriately chosen embedding

Az on-line világban hagyott virtuális lábnyomokban rejlő információk és azok veszélyei (In on-line world leaven virtual footprints information and those dangers)

A mindennapi, szinte folyamatos jelenlét a hálózaton számos melléktermékkel jár. Minden bejelentkezés, üzenet, vásárlás, akció adatok tömegét hagyja az interneten. A cikkben arra kívánnak a szerzők rámutatni, hogy ezeket az adatokat valaki vagy valakik összegyűjthetik, és esetleg olyasmire is használhatják, amihez nem járulnánk hozzá, ha ezt megkérdeznék. A szerzők nem foglalkoznak a rosszindulatú, esetleg bűntények elkövetésének céljára történő illegális adatgyűjtéssel, illetve -hasznosítással, azt kívánták bemutatni, hogy teljesen legális, ún. „white hat” eszközökkel is tartalmas felhasználói profilt lehet összeállítani. Szót ejtenek arról is, hogyan lehet megnehezíteni azok dolgát, akik rólunk szeretnének információt gyűjteni. ____ Everyday, almost continuous presence on the web results number of by-products. Each login, message, shopping, action leaves mass of data on the internet. In this article, the authors wish to point out that these data may be collected by somebody or somebodies. They wanted to introduce you that a meaningful user profile can be compiled by completely legal, so-called „White hat”tools. It also notes about how you can make more difficult their job, who would like to collect information from us

Sunburn assessment: A critical appraisal of methods and techniques for characterizing the damage to apple fruit

Many methods and techniques have been introduced for measuring alterations in the fruit and in its surrounding environmentrelated to sunburn incidence. The research objectives, fruit materials and the environment to be evaluated dictate the methods to follow. Theseprocedures are either non-destructive and involve techniques that allow us to track the course of sunburn development and relatedenvironmental parameters, or destructive and involve the removal of fruit from the tree for field/laboratory measurements. Techniquesemployed can be used for pre-symptomatic monitoring (before symptoms become visible) or characterizing the symptoms already present.The principles behind the measurements and their usefulness for sunburn assessments are discussed and critically evaluated in this reviewpaper. Descriptions and evaluations of the methods and techniques were made in the following groups: 1. Thermal measurements; 2. Visualassessments; 3. Fruit quality measurements; 4. Measurements of physiological and biochemical alterations; and 5. Practical evaluation ofsunburn damage. Thermal measurements involve methods tracking the ambient temperature and fruit surface temperature, and their relationto sunburn formation. Visual assessments cover all measuring techniques (skin color, chlorophyll fluorescence, radiation reflection, electronmicroscopy) that are able to detect changes on/in the fruit skin related to sunburn formation. Fruit quality measurements are used to point outdifferences in qualities (soluble solids, firmness, titratable acidity, and water content) between unaffected and sunburned areas of the fruit. Themeasurements of physiological and biochemical alterations (gas exchange, pigment analysis, enzyme activity, gene expression) give us abetter insight to the mechanism of sunburn formation. Practical evaluations involve many procedures that are used by scientists to characterizethe susceptibility of cultivars, evaluate protection technology, etc. For this purpose, the following methods are in use: expressing thepercentage of the total fruit surface area affected by sunburn or the percentage of the total number of fruits damaged on the tree, or even ascale based on the severity of the symptoms occurred. All assessing methods and techniques described here have their pros and cons as wellas their specific applicability, therefore any of these cannot be favored to use exclusively for assessing sunburn incidence. The combinationof these techniques will be the best choice to meet a given research objective perfectly

EFFECT OF NUTRIENT SUPPLY ON FRUIT QUALITY OF APPLE (Malus domestica BORKH.)

Observations were carried out in the eastern part of Hungary. In this experiment we studied the nutrient supplyreaction of four apple cultivars (Golden Delicious, Granny Smith, Idared and Jonathan Csány) under different Nand NPK-doses. The following fruit quality parameters were detected: fruit diameter, fruit height, fruit weight, fl esh fi rmness, colour-cover and we studied the thicket of foliage of trees. The research results showed, that N-fertilization has a great effect on fruit quality. This appears in the cases of increase of fruit largeness. The increase is proportional to N-levels. Moderate N-doses plus PK-addition had also positive effects. The nutrient supply increased vegetative area in addition to the generative parts, in particular pure N fertilizer. But the thicked foliage hindered the growth of fruit weight and colour-cover, also decreased the fruit quality. And decreased the fl esh fi rmness of cultivars, that has a negative effect on storageability