36 research outputs found
Developing an integrated land use planning system on reclaimed wetlands of the Hungarian Plain using economic valuation of ecosystem services
The establishment of a sustainable land use system is crucial in Hungary (SE Europe) where 30% of croplands lie on former floodplains, and 40–45% of arable lands are drought-prone. We calculated and compared the monetary value of the main wetland ecosystem services, the profitability of land use and the additional costs of grain producer system on land at risk from groundwater inundation on the Hungarian Plain. We show that orchards and forestry generate a much higher profitability in former wetlands than cropland farming. Using the replacement cost method, we prove that the reservoir capacity of restored wetlands with an ecologically optimal 0.5 m water depth could replace 2150 €ha−1 flood protection investment cost. The calculated costs of protecting land under the two highest groundwater risk categories between 1999–2005 was 37.2 €ha−1 y−1 and 14.9 €ha−1 y−1, respectively. Although the flood protection benefits of former wetlands may provide an appropriate value base for restoration per se, combined with the potential advantages of land use change from cropland to forest in former wetlands and the carbon sequestration benefit provide ‘win-win’ solutions for land users and institutional actors interested in flood prevention, environmental protection and climate mitigation
Diszkrét geometria és geometriai konvexitás = Discrete geometry and geometric convexity
Bezdek K. és R. Conelly [2] bebizonyította a Kneser-Poulsen sejtést a d-dimenziós szférikus tér félszféráira, azaz megmutatták, hogy ha P és Q két olyan szférikus d-politóp, melyek mindegyike n darab félszféra metszete, továbbá bármely két Q-hoz tartozó félszféra szöge legalább akkora, mint a nekik megfelelő P-hez tartozó félszférák szöge, akkor Q térfogata legalább akkora, mint P térfogata. Bezdek K. és Naszódi M. [12] bevezette a gömbpoliéder fogalmát. Ezek véges sok egybevágó gömb metszeteként előálló halmazok. Bebizonyították a háromdimenziós euklidészi tér gömbpoliédereire a Cauchy-féle merevségi tétel analogonját. Ugyanők, Lángi Zs. és P. Papez [21] a konvex politópok elméletének sok klasszikus eredményét általánosította gömbpoliéderekre. Böröczky K. és Szabó L. [3] lényegesen megjavította a gömbön elhelyezett 13 pont közti minimális távolság maximumára eddig ismert becslést. Bezdek K. és A. Litvak [22] bevezették a csúcsindex fogalmát, ami azt méri, hogy milyen jól lehet egy konvex testet kevés csúcsú poliéderrel közelíteni. Aszimptotikusan éles becslést adtak tetszőleges d-dimenziós konvex test csúcsindexére. A csúcsindex szorosan kapcsolódik a testek megvilágítási paramétereihez, amivel kapcsolatban Bezdek K., Böröczky K. és Kiss Gy. [16] értek el új eredményeket. Böröczky K. és ifj. Böröczky K. vékony gömbhéjakba írt minimális térfogatú poliéderek jellemzését adták meg, többek közt így karakterizálták a szabályos oktaédert és ikozaédert. | K. Bezdek and R. Conelly [2] proved the Kneser-Poulsen conjecture for hemispheres of the d-dimensional spherical space namely, if P and Q are intersections of the same number of hemispheres, and the distances between the centers of each pair of hemispheres belonging to Q are at least as big as the distances between the centers of the corresponding hemisperes of P, then the volume of P is greater than or equal to the volume of Q. Ball-polyhedra were introduced by K. Bezdek and M. Naszódi in [12]. They proved the analogue of Cauchy's rigidity theorem for ball-polyhedras of E^3. K. Bezdek, Zs. Lángi, M. Naszódi and P. Papez [17] generalized several theorems of the theory of convex polytopes to ball-polyhedra. K. Böröczky and L. Szabó [3] considered the problem of arranging 13 points on the sphere so as to maximize the minimum distance between any two of them. They improved the known bounds. K. Bezdek and A. Litvak [18] introduced the notion of vertex index, which measures how well a convex body can be approximated by a convex polytope. They proved asimptotically sharp bounds for the vertex index. The vertex index is closely connected to the illumination parameters of the body, which were studied by K. Bezdek, K. Böröczky and Gy. Kiss [16]. K. Böröczky and K. Böröczky Jr. succeded to characterize the convex bodies of minimal volume in E^3 that contain a unit ball, and whose extreme points are of distance at least r>1 from the centre of the unit ball
Special multicolor illumination and numerical tilt correction in volumetric digital holographic microscopy
We introduce a color imaging method in our digital holographic microscope system (DHM). This DHM can create color images of freely floating, or moving objects inside a large volume by simultaneously capturing three holograms using three different illumination wavelengths. In this DHM a new light source assembly is applied, where we use single mode fibers according to the corresponding wavelengths that are tightly and randomly arranged into a small array in a single FC/PC connector. This design has significant advantages over the earlier approaches, where all the used illuminations are coupled in the same fiber. It avoids the coupling losses and provides a cost effective, compact solution for multicolor coherent illumination. We explain how to determine and correct the different fiber end positions caused tilt aberration during the hologram reconstruction process. To demonstrate the performance of the device, color hologram reconstructions are presented that can achieve at least 1 μm lateral resolution
Petrographical and geochemical study of the magmatic phases and hydrothermal vein types of the Bolcana porphyry Cu-Au mineralization
Caveolák szerepe a szürke hályog képződésében: humán szemlencse epithelsejtjeinek vizsgálata
Introduction: Caveolae are flask shaped with 50-100 nm size, non-clathrin associated invaginations of the plasmam-embrane. The main membrane protein of the structures is caveolin-1. Caveolae play an important role in numerous cellular functions including vesicular transport and cell-cycle regulation, and create platforms for classical and alternative signaling pathways. According to international studies, caveolae may influence the physiology and pathology of lens epithelial cells