Autoencoding sensory substitution

Tens of millions of people live blind, and their number is ever increasing. Visual-to-auditory sensory substitution (SS) encompasses a family of cheap, generic solutions to assist the visually impaired by conveying visual information through sound. The required SS training is lengthy: months of effort is necessary to reach a practical level of adaptation. There are two reasons for the tedious training process: the elongated substituting audio signal, and the disregard for the compressive characteristics of the human hearing system. To overcome these obstacles, we developed a novel class of SS methods, by training deep recurrent autoencoders for image-to-sound conversion. We successfully trained deep learning models on different datasets to execute visual-to-auditory stimulus conversion. By constraining the visual space, we demonstrated the viability of shortened substituting audio signals, while proposing mechanisms, such as the integration of computational hearing models, to optimally convey visual features in the substituting stimulus as perceptually discernible auditory components. We tested our approach in two separate cases. In the first experiment, the author went blindfolded for 5 days, while performing SS training on hand posture discrimination. The second experiment assessed the accuracy of reaching movements towards objects on a table. In both test cases, above-chance-level accuracy was attained after a few hours of training. Our novel SS architecture broadens the horizon of rehabilitation methods engineered for the visually impaired. Further improvements on the proposed model shall yield hastened rehabilitation of the blind and a wider adaptation of SS devices as a consequence

The effect of periphyton on the light environment and production of Potamogeton perfoliatus L. in the mesotrophic basin of Lake Balaton

Light within the littoral zone affects the productivity and interaction between periphyton and its macrophyte substrate. The effect of periphyton on macrophyte photosynthesis, seasonal variation and vertical distribution of periphyton on artificial substrates (plastic strips), and the effect of periphyton on the light environment was studied in Lake Balaton. Data showed that an average of 4.1±0.4 mg (dry weight) cm-2 of periphyton had accumulated on the plastic strips after 8.8±0.4 days. This biomass corresponded to 294±30 μg m-2 chl-a of epiphytic algae and blocked 92.3±0.8 % of the depth specific radiation. Seasonal variation and specific vertical distribution of periphyton were observed. The most active time of periphyton accumulation corresponded to spring up until mid-June. Later in the year, the amount of periphyton significantly decreased. The optimal conditions for periphyton accumulation were at 30-40 cm depth. Most of the light reaching the adaxial leaf surface was attenuated by periphyton, decreasing the production of Potamogeton perfoliatus by 60-80%. This increased the importance of backscattered light that corresponded to 10-15% of the macrophyte production. A smaller part of the periphyton consisted of precipitated inorganic material, while epiphytic algae, making up the majority of the periphyton, were connected to both benthic (dominantly benthic penales) and pelagic (very close seasonal dynamics of pelagic and epiphytic biomass) algae. Periphyton affects macrophyte production especially in spring and in the upper water layers even in a mesotrophic water body. This increases the importance of the light absorbed through the abaxial side of the leaf and confirm the role of periphyton in transition from clear to turbid water states

A határmenti fekvés hatása a városi tér fejlődésére = The effects of border area location on the development of urban space

Hipotézisünk szerint egy államhatár mentén fekvő város belső terének fejlődését módosítja határmenti fekvése. Ez nagymértékben meghatározza a városba települő multinacionális vállalatok, és más kereskedelmi és szolgáltató intézmények telephelyválasztását, mely napjainkban a város egyik fő funkcióját képezi. Átalakítja kiskereskedelem térbeli struktúráját, a vállalkozások tulajdonosi összetételét, profilját, továbbá hat az ingatlanpiacra. E hipotéziseket Szeged példáján igazoltuk a kereskedelem térbeliségének vizsgálatával. 2005 őszén kérdőíves felmérést végeztünk, feltérképeztük Szegeden belül a fő közlekedési útvonalak melletti kiskereskedelmi bolthálózatot. A kb. 500 üzlet tulajdonosával vagy vezetőjével kérdőívet töltettünk ki. A válaszok alapján tematikus térképeket készítettünk, s megállapítottuk, hogy hol helyezkednek el azok az üzletek, amelyek határon túli vásárlókra építik vállalkozásukat. Összességében igazolódni látszik, hogy a határ menti fekvés jelentős szerepet játszik Szeged kiskereskedelmének és egyéb szolgáltatásainak életében, s a határon átnyúló kereskedelem stabilnak tűnik annak ellenére, hogy az azt létrehozó előnyök aránya csökkent. A határon túli forgalom által érintett üzletek a fő közlekedési utak mentén a város különböző részein egyaránt megtalálhatók, s nem koncentrálódnak a város államhatárhoz közelebb eső részére. | According to our hypothesis border zone location has a transformative role in the development of urban space. For multinational and commercial companies as well as for other service providers it determines the choice of place of business. This feature is one of the main features of urban characteristics these days. Border zone location also transfrorms the spatial structure of small trade, the composition of business ownership as well as business profiles and it also has an impact on the real estate market. The above hypotheses have been proved through the analysis of the spatial structures of commercial businesses in Szeged. The investigation was carried out in the fall of 2005 by using questionnaires. Then a network of retail shops was mapped, businesses, which are located along the main roads. The owners of about 500 businesses were asked to fill in the questionnaires. On the basis of their answers thematic maps were drawn and the location of those businesses was identified which rely on customers from across the border. In summary it seems justifiable that border zone location plays a significant role in Szeged?s retail businesses, services and transborder trade. Businesses appear stable in spite of the fact, that advantages of border zone location have recently been diminishing. It has also been proved that the businesses, which were opened in order to utilise these advantages can be found near main roads as well as in other places all over the town, so their location does not depend on the nearness of the national border

Nemzetközi és hazai zöldség-gyümölcsfogyasztás, módszertani kérdések = International and domestic fruit and vegetable consumption, methodological issues

A zöldség- és gyümölcsfogyasztás többszintű közvetítő szerepet játszik az emberek egészségi állapota és testsúlya alakulásában. Egyértelmű ok-okozati kapcsolat még a legmodernebb módszerekkel is nehezen található, mivel különösen komplex biológiai és viselkedési kapcsolatban van az egészséggel. Az alacsony zöldség- és gyümölcsfogyasztással összefüggő betegségek által jelentett közteher jelentős, de nem a legjelentősebb. A zöldség és a gyümölcs kategória meghatározása annak ellenére nem egységes, hogy mindig kapcsolódik azok egészségügyi jelentőségéhez, vagyis tápanyag- és rosttartalmához. A nemzeti és a szakmai zöldség- és gyümölcsfogyasztási ajánlások általában követik a WHO ajánlásokat, de nem minden esetben esnek egybe azzal. A sajnálatos módszertani és értelmezési nehézségeken túl ebben az esetben a cél az „attitűd-viselkedés rés”, áthidalása, vagyis annak a bonyolult problémának a legyőzése, hogy az emberek mást akarnak tenni, mint amit a valóságban tesznek. A Központi Statisztikai Hivatal, Háztartás Költségvetési Felvétel (KSH-HKF) adatai alapján a legnagyobb mennyiségben vásárolt zöldség- és gyümölcskategóriákat mutatjuk be településméret, vásárolt érték, termelt mennyiség, valamint a háztartás nagysága alapján. Fruit and vegetable consumption plays a multi-level intermediary role in the development of people’s health status and body weight. Even using state-of-the-art methods, it is hard to find unambiguous causality, because it has an especially complex biological and behavioral connection to health. The public burden imposed by illnesses related to low fruit and vegetable consumption is significant, but not the most significant. Definition of the fruit and vegetable categories is not uniform, even though it is always related to their health significance, i.e. their nutrient and fiber contents. National and professional fruit and vegetable consumption recommendations usually follow WHO recommendations, but do not always coincide with the latter. In addition to unfortunate methodological and interpretation difficulties, the goal in this case is to bridge the „attitude-behavior gap” , i.e. conquering the complex problem that people want to act differently from what they actually do. Based on the data of the Household Budget Survey of the Hungarian Central Statistical Office (CSO-HBS), fruit and vegetable categories that are bought in the largest amounts are presented, according to settlement size, value bought, quantity produced, as well as the size of the household

The packing density of the n-dimensional cross-polytope

The packing density of the regular cross-polytope in Euclidean $n$-space is unknown except in dimensions $2$ and $4$ where it is 1. The only non-trivial upper bound is due to Gravel, Elser, and Kallus (2011) who proved that for $n=3$ the packing density of the regular octahedron is at most $1-1.4\ldots\times 10^{-12}$. In this paper, we prove upper bounds for the packing density of the $n$-dimensional regular cross-polytope in the case that $n\geq 7$. We use a modification of Blichfeldt's method due to G. Fejes T\'oth and W. Kuperberg (1993)