Depth of Investigation of Dipole-dipole, Noncolinear and Focused Geoelectric Arrays

Investigation depth of various DC geoelectric arrays has always been in the focus of interest of geoelectricians. According to its classical definition (Roy and Apparao 1971), the depth of investigation is the depth of the maximum response due to a horizontal thin-sheet embedded in a half-space, by using a given geoelectric array. On basis of the graph of the thin-sheet response as a function of the depth (from the so-called „depth of investigation characteristics” or DIC function) Edwards (1977) found more realistic to compute the medium depth than the depth of the maximum response. DIC functions have been known so far only for simple colinear arrays, the dipole equatorial array and two focused arrays. Here we provide a summary about the depth of investigation values of various dipole-dipole arrays (for parallel, perpendicular, radial, azimuthal ones), and for the most important noncolinear and focused arrays. Depth of investigation values are computed from both approaches. DIC functions (obtained by a new analytical formula) are also presented, as illustrations. The analytical formula can be used to compute DIC function of any surface geoelectric array. A systematic interpretation of the resulting depth of investigation values provides simple but useful thumb-rules for practical applications

Report of review of St Stephen’s Children’s Centre, Newham: services for children aged up to 3 years

Formation of surface depressions is a significant geological hazard. Prediction of future sinkholes in buried karstic areas needs knowledge about the subsurface. In order to determine the varying topography of the karstifiable bedrock we carried out multielectrode measurements. Due to the hard field conditions, the bedrock depth could not be detected. The resistivity anomalies in some places had a seasonal variation (low-resistivity in springtime, high-resistivity in the end of summer); therefore we interpreted the springtime resistivity lows as indicators of locations with high water content, that is as high porosity, saturated with water. At the same time, when pushing the current- and potential electrodes into the ground, we discovered a regularity in the areal distribution of the soil's rock debris content. Therefore we carried out a systematic electrode-pricking experiment, and categorized the soil's "toughness" corresponding to soft penetration, scratching or blockage within the upper 30 cm. We have found a close relationship between the locations of resistivity- and the soil's toughness extremes. From some epikarstic features we think that high "pricking probe" values indicate smaller depths of the bedrock. The corresponding (springtime) resistivity minima may indirectly indicate more or less collapsed horsts of the carbonate rock

Strengthening the Small and Medium Enterprise Sector by Switching to Bills and Notes

The proposal to switch to bills and notes might be shocking. The fact that Act CLXXXV of 2017 on the Regulations for Bills of Exchange and Promissory Notes entered into effect in Hungary on 1 January 2018 in order to enforce the uniform regulations pertaining to the legislation on bills of exchange and promissory notes, yet we still cannot talk about the issuance and use of bills and notes, is just as odd. In our study, we argue that in the absence of other short-term corporate securities, bills and notes could help the liquidity management of SMEs owing to their elaborated legal background. We briefly present the importance of corporate securities in the financing of companies both on domestic and international level, as well as the evolution of financial services related to bills and notes in the mirror of the statistics of the Hungarian supervisory authority, and we also provide possible ways for developing the financial services related to bills and notes. We review the previous and current Hungarian legal-regulatory environment of bills and notes and then summarise the arguments for their use in Hungary

Non-conventional geoelectric arrays : practical results of the OTKA project K49604

In this paper we provide a comprehensive summary about the practical results of the OTKA project K49604. 1. We calculated the consequences of incorrect positioning of the electrodes for various multielectrode systems. In practice these effects were found to be negligible. The only exception is the case of rocky surface, where it is impossible to put the electrodes in the desired positions. The errors can however be kept within an acceptable range, if the electrodes of the linear arrays are put off-set, at right angles from the measuring line. A five-six times larger off-set has less effect than a certain mis-position along the line, connecting the electrodes. 2. We carried out tensorial geoelectric measurements around the Cistercian Monastery at Pilisszentkereszt. Areal measurements provide much more detailed and unambiguous anomalies than 2D profile measurements, and the tensor invariant representation of apparent resistivity anomalies provides a realistic picture about the lateral variation of the subsurface resistivity, even in field circumstances. 3. We tested the applicability of 3D electrical resistivity tomography (ERT) technique to detect landmines in different soil conditions and at various depths. Metallic and non-metallic landmines buried in wet and dry soils had been synthetically modeled. According to the inverted resistivity data using the dipole axial array in wet environment, it was possible to locate the metallic and non-metallic landmines as long as the noise level was about 5%. 4. We elaborated moreover a geoelectrical procedure which is able to map multidirectional fissure systems by combining geoelectrical profiling and geoelectrical azimuthal measurements. Results received by using both the so-called null-, and traditional arrays were jointly interpreted. The humidity of the fissures affects the measured results significantly, and in a meaningful way. 5. We presented the socalled standardized pricking probe (PP) surveying technique and demonstrated its usefulness in an archaeological study. The PP images proved to be definitely more close to the realistic shape of the buried chapel than the geoelectric and magnetic measurements, and they also revealed more details about the subsurface than the georadar. The optimum PP parameters: horizontal interval, pricking depth, observable quantity and its way of presentation were optimized through field experiments. For more details see the cited publications. The figures ever published in Hungarian journals are not reproduced here. Keywords: 3D ERT; geometric nois

Mit hozott édesapám? : döntést - idiomatikus és félig kompozicionális magyar igei szerkezetek azonosítása párhuzamos korpuszból

Cikkünkben egy olyan algoritmust mutatunk be, amelynek segítségével elemzett angol-magyar párhuzamos korpuszból gyűjtöttünk idiomatikus és félig kompozicionális igei szerkezeteket a szómegfeleltetések felhasználásával. Mivel a kutatás kontextusát egy kérdések megfogalmazását lehetővé tevő elemző megalkotása jelentette, ezek a szerkezetek elsősorban abból a szempontból érdekeltek minket, amennyiben a szerkezet egyes elemeire a kompozicionalitás hiányából kifolyólag nem lehet kérdezni. Az eredményeket összevetettük egy ilyen szerkezeteket tartalmazó létező erőforrással, és azt találtuk, hogy algoritmusunk sok új számunkra érdekes nem vagy részben kompozicionális igei szerkezetet azonosított