92 research outputs found
A költségvetési csalás a statisztikai adatok tükrében a rendszerváltozástól napjainkig
In the context of economic crime a completely new economic-social environment was formed during the mid-1990s in Hungary. The term white-collar crime has appeared, and the issue of interconnected VAT fraud strengthened. After joining the European Union, the practice of fiscal fraud related to acquisitions within the Community has evolved. These crimes included various VAT related frauds such as accepting pro forma invoices related to domestic sales activities and other economic activities related to acquisitions and sales within the Community. Whereas 180 adults were convicted for fiscal fraud in 2013; this figure has grown to 1637 adults and 2 juveniles by 2018. It is difficult to fight against white-collar crime. Crime prevention may therefore be necessary in order to fight off the number of frauds as well as diverting law enforcement agencies into the right direction regarding ongoing procedures.Magyarországon a 90-es Ă©vek közepĂ©n teljesen Ăşj gazdasági-társadalmi környezet formálĂłdott a gazdasági bűncselekmĂ©nyekkel összefĂĽggĂ©sben. Megjelent a fehĂ©rgallĂ©ros bűnözĂ©s fogalma, Ă©s megerĹ‘södött a láncolatos áfacsalás kĂ©rdĂ©se. Az EurĂłpai UniĂłhoz valĂł csatlakozás után kialakult a közössĂ©gen belĂĽli termĂ©kbeszerzĂ©shez kapcsolĂłdĂł költsĂ©gvetĂ©si csalás gyakorlata, amely általános forgalmi adĂłt Ă©rintĹ‘ terĂĽletei a belföldi tevĂ©kenysĂ©ghez kapcsolĂłdĂł fiktĂv számlák befogadása, a közössĂ©gen belĂĽli beszerzĂ©shez Ă©s a közössĂ©gen belĂĽli Ă©rtĂ©kesĂtĂ©shez kapcsolĂłdĂł gazdasági cselekmĂ©nyek lettek. AmĂg 2013-ban országosan 180 felnĹ‘ttkorĂşt ĂtĂ©ltek el költsĂ©gvetĂ©si csalás miatt, addig 2018-ra ez a szám már 1639-re nĹ‘t (1637 felnĹ‘ttkorĂş Ă©s kĂ©t fiatalkorĂş). A fehĂ©rgallĂ©ros bűnözĂ©ssel szemben nehĂ©z felvenni a kĂĽzdelmet, ezĂ©rt szĂĽksĂ©gessĂ© válhat a megelĹ‘zĂ©s a bűncselekmĂ©nyek visszaszorĂtása Ă©rdekĂ©ben, illetve a már folyamatban lĂ©vĹ‘ eljárásokban a bűnĂĽldözĹ‘ szervek helyes szakmai irányba valĂł terelĂ©se
THE DEPENDENCE OF SCHOTTKY BARRIER HEIGHT ON THE RATIO OF DIFFERENT METAL COMPONENTS
In order to understand the variation of the barrier height of different metal-semiconductor contacts, a model for common effective contact (CEC) was proposed. The CEC consists of several primary diodes prepared or formed by different metals on the same semiconductor substrate. The smallest interfacial area of each primary diode was assumed to be the smallest limitation of area on which the Schottky contact's properties exist. The results of the investigation show that all electrical properties - the barrier height especially - of the CEC depend on the ratio of the interfacial area occupied by each metal component in the common effective interface. This result may be applied to the metal compound-semiconductor contact to investigate the variation of potential barrier height, as well as the electrical characteristics of multilayer metal-semiconductor contacts
Félvezető szenzorok elektronikus zajának eredete = The origin of electronic noise in semiconductor sensors
A projekt támogatásának felhasználásával lĂ©trehoztunk egy alacsonyfrekvenciás zaj mĂ©rĂ©sĂ©re alkalmas laboratĂłriumot. A fĹ‘ műszer az SR785 spektrum analizátor. Szenzor anyagok Ă©s szenzorok zajtulajdonságait vizsgáltuk. A zajmĂ©rĂ©sek segĂtsĂ©gĂ©vel Ă©rtelmeztĂĽk a porĂłzus Si áramvezetĂ©si mechanizmusát. Zaj szempontbĂłl optimalizáltuk az PbS fotĂłellenállás technolĂłgiáját. MegállapĂtottuk, hogy az ion-implantantált piezo-ellenállások zaja kritikusan fĂĽgg az ellenállás-hordozĂł közti p-n átmenet zárĂłirányĂş áramátĂłl. Vizsgáltuk a szenzorok zaja miatti elvi alkalmazási korlátozásokat. Rendszeresen szerepeltĂĽnk a Fluctuation and Noise Symposium-on. Számos fiatal kutatĂłt Ă©s gyakornokot vontunk be a munkákba. | Low-frequency electrical noise measuring set up has been built due to the financial support of the project. The main instrument is the SR785 dual channel dynamic signal analyser. The noise characteristics of sensors and sensor materials were investigated. The current conduction mechanisms in porous Si were interpreted taking into account the noise. The technology of PbS photo resistor was optimised in respect the noise. It was pointed out that the noise in ion-implanted pieso-resistor depends critically on the reverse current of the p-n junction between the resistor and the substrate. The noise limitations of the figures of merits of sensors were also investigated. Papers were presented in each year on the Fluctuation and Noise Symposium. Numerous young scientists and trainees were involved in the work
Millimeter wave detection by thermopile antenna
AbstractIn this paper a novel MEMS thermopile structure is proposed, which consist of linearly arranged p- and n- type polysilicon strips instead of the conventional loop-like configuration. It is shown that these devices sense the millimeter wave radiation beyond the infrared. The polarity and frequency dependence of the sensitivity prove that these strips behave as absorbing antennas towards the microwave/millimeter wave radiation. The induced current is calculated having a maximum in the geometrical center of the antenna, exactly at the position where the hot end of the thermopair is located. The measured responsitivities to direct heating, infrared radiation, 13 GHz microwave radiation and 100 GHz millimeter-wave radiation are presented
Isotropic Broadband E-Field Probe
An E-field probe has been developed for EMC immunity tests performed in closed space. The leads are flexible resistive transmission lines. Their influence on the field distribution is negligible. The probe has an isotropic reception from 100 MHz to 18 GHz; the sensitivity is in the 3 V/m–10 V/m range. The device is an accessory of the EMC test chamber. The readout of the field magnitude is carried out by personal computer, which fulfils also the required corrections of the raw data
SiC és más nagy tiltott sávú félvezető anyagok kutatása = Research of SiC and other wide band gap semiconductor materials
A kutatás során egy magas hĹ‘mĂ©rsĂ©kletű elektromos mĂ©rĂ©sekre alkalmas mĂ©rĹ‘rendszert fejlesztettĂĽnk Ă©s SiC anyag mĂ©rĂ©sĂ©re alkalmas mintakĂ©szĂtĂ©si eljárást alakĂtottunk ki. A berendezĂ©s fejlesztĂ©sĂ©t kĂ©nyszerbĹ‘l vĂ©geztĂĽk, mert a pályázat költsĂ©gvetĂ©se nem tette lehetĹ‘vĂ© a mĂ©rĂ©sre szĂĽksĂ©ges berendezĂ©sek beszerzĂ©sĂ©t. A berendezĂ©s-fejlesztĂ©s pĂ©nzĂĽgyi Ă©s technikai szempontbĂłl is nehĂ©z volt, mert a megoldásához sok egyedi feladatot kellett megoldani Ă©s összehangolni, limitált költsĂ©gvetĂ©sbĹ‘l. A számĂtástechnika fejlĹ‘dĂ©se olyan iramĂş, hogy a mĂ©rĂ©svezĂ©rlĂ©s mĂłdját a futamidĹ‘ alatt meg kellett változtatni. Ebben a munkában továbblĂ©pĂ©s ezen a terĂĽleten az lehet, hogy a berendezĂ©s megĂ©pĂtĂ©sĂ©re használt megoldások egy kĂ©sĹ‘bbi ipari fejlesztĂ©sbe beĂ©pĂĽlhetnek. A kutatĂłmunka - a berendezĂ©s-fejlesztĂ©ssel inkább párhuzamosan, mint összhangban - elsĹ‘sorban kĂĽlönbözĹ‘ III-V Ă©s szilĂcium kvantumszerkezeteken törtĂ©nt. KĂĽlönbözĹ‘ kvantumszerkezetek elektromos paramĂ©tereinek Ă©s hibahelyeinek tulajdonságait vizsgáltuk. A mikroszkĂłpia vizsgálatok termĂ©szetes szĂĽksĂ©gessĂ©ge mellett a mĂ©rt eredmĂ©nyek elmĂ©leti Ă©rtelmezĂ©se az, ami lĂ©nyegesen Ăşj megközelĂtĂ©st igĂ©nyel, mert a vizsgált szerkezetekben jellemzĹ‘, hogy a klasszikus (makroszkĂłpikus) mĂ©retekre levezett összefĂĽggĂ©sek a mikroszkĂłpikus eszközökön vĂ©gzett mĂ©rĂ©sek leĂrására gyakran nem alkalmasak. Ennek egyik alapvetĹ‘ oka lehet, hogy a kvantummechanika mĂ©rettartományába esĹ‘ objektumok leĂrására a szilárdtestfizikában Ăşj modellek kialakĂtására lesz szĂĽksĂ©g. | A measuring system was developed for measuring high temperature electronic characteristics of devices and a procedure was developed for preparation of samples on SiC for ohmic contacts, Schottky barriers and MOS structures. The measuring system was developed for the reason of shortage of money, since the budget of the project did not allow the buying of a measuring system of this kind. The development was difficult both financial and technical point of view, since several tasks had to be solved and synchronized from a limited budget. The development of the computers is so fast, that the concept of computer control had to be changed during the project. In this development further step might be if some solutions realized in the development can be built in a later industrial development. The research - rather parallel than in harmony with measuring development - mainly was focused on different nanostructures in III-V and silicon quantum structures. Besides the natural need for microscopic investigation on these structures the theoretical interpretation of the measured results requires new approach, since the approximations developed for classical (macroscopic) often fail to explain properly the results measured on microscopic devices. A basic reason of it may be that new models have to be developed for describing the quantum mechanical sized solid phase objects
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