Towards an RFID microsystem for surgical instrument detection using millimeter waves

Misplacement of surgical instruments inside an operating room is a frequent mistake that can bring unnecessary complications. We propose a system that can prevent these, through wireless communication. In this paper, we investigate the use of the 55-60 GHz band in the implementation of a RFID system that presents very interesting characteristics like improved security and small size. From the measurements already made, it's expected the RFID system operating in the 60 GHz ISM will work at distances, at least, up to 5 meters. Furthermore, it is proposed a solution to obtain a fully integrated system based on an on-chip antenna that could be integrated with an RF CMOS chip based on 65 nm CMOS technology.info:eu-repo/semantics/publishedVersio

Experimental Determination of Nucleation Scaling Law for Small Charged Particles

We investigated the nucleation process at the molecular level. Controlled sticking of individual atoms onto mass selected clusters over a wide mass range has been carried out for the first time. We measured the absolute unimolecular nucleation cross sections of cationic sodium clusters Na_{n}^{+} in the range n=25-200 at several collision energies. The widely used hard sphere approximation clearly fails for small sizes: not only should vapor-to-liquid nucleation theories be modified, but also, through the microreversibility principle, cluster decay rate statistical models

60 GHz on-chip antenna array with efficiency improvement using 3D microfabrication technology

The 55-65 GHz band has very interesting characteristics, such as allowing high-bandwidth communications and improved security (due to high absorption). From the antenna point of view, it also has the interesting feature of allowing the fabrication of very small antennas. Because they're so small, these antennas can be placed directly on-chip. However, silicon is a high loss material at such high frequencies. This paper proposes a solution to obtain one antenna array with improved efficiency. Instead of designing the antennas on top of silicon, 3D antennas are designed to lie above the silicon substrate.This work was supported by Portuguese Foundation for Science and Technology: FCT-PTDC/EEI-TEL/2881/2012, Programa Operacional Temático Fatores de Competitividade (COMPETE) and Fundo Comunitário Europeu FEDER.info:eu-repo/semantics/publishedVersio

On-chip, efficient and small antenna array for millimeter-wave applications

The high path losses experienced by wireless applications at millimeter wavelengths may be mitigated using high gain antennas. The intrinsic small wavelengths makes very attractive to develop solutions with on-chip integrated antennas. However, due to silicon high losses, on-chip antenna elements on RFCMOS technology have reduced efficiency. This paper proposes a solution to obtain an on-chip integrated antenna array based on 3D efficient antenna elements. A 4 element antenna was designed to operate at 57.5 GHz central frequency, with maximum gain of 5.8 dB, and maximum expected efficiency of 45%.Work supported by Portuguese Foundation for Science and Technology (SFRH/BD/63737/2009, and PTDC/ EEI-TEL/ 2881/2012, Programa Operacional Temático Fatores de Competitividade-COMPETE, and Fundo Comunitário Europeu-FEDER).info:eu-repo/semantics/publishedVersio

Contribuição para o conhecimento de alguns hemípteros que atacam as plantas cítricas

Contribution to the knowledge of some Citrus damaging Hemiptera. This paper deals with field and laboratory investigations on Crinocerus sancius (Fabr., 1775), Leptoglossus gonagra (Fabr., 1775), and. L. stigma (Herb., 1784), all belonging to the family Coreidae, Order Hemiptera. These three species are noxious to several fruits, including citrus. The two Leptoglossus and the damages they cause on oranges have been investigated by several writers in the last 25 years. On the other hand, c. sancius was discovered damaging Citrus only in 1959, increasing in importance since its discovery. Redescription of the adults, bionomical notes, hosts, and so on, are the main purpose of this study

Contribuição para o conhecimento do pulgão Aphis nerii Boyer de Fonscolombe, 1841 (Homoptera, Aphididae)

This paper deals with the oleander aphid, Aphis nerii Boyer de Fonscolombe, 1841, a very common aphid at Piracicaba (State of São Paulo, Brazil)

Contribuição para o conhecimento do lepidóptero saturnídeo Rothschildia arethusa (Walker, 1855)

In this paper, the writers present a summary of their investigations on Rothschildia arethusa (Walker, 1855) ( Lepidoptera, Saturniidae ) performed at the Escola Superior de Agricultura "Luiz de Queiroz", Piracicaba, State of São Paulo, Brazil. The larva was found to feed on "bacupari do mato" (Rheedia sp.) ( Guttiferae ). Some bionomical notes on the larval and pupal stages and the description of the adult are the mainly subject

Observation of coherent transients in ultrashort chirped excitation of an undamped two-level system

The effects of Coherent excitation of a two level system with a linearly chirped pulse are studied theoretically and experimentally (in Rb (5s - 5p)) in the low field regime. The Coherent Transients are measured directly on the excited state population on an ultrashort time scale. A sharp step corresponds to the passage through resonance. It is followed by oscillations resulting from interferences between off-resonant and resonant contributions. We finally show the equivalence between this experiment and Fresnel diffraction by a sharp edge.Comment: 4 pages, 4 figures, to appear in PR

Estudo descritivo e bionômico de Cerosipha forbesi (Weed, 1889) (Horn., Aphididae)

This paper deals with Cerosipha forbesi (Weed, 1889) (= Aphis forbesi) the strawberry root aphid, one of the noxious insects to the strawberry plant in the State of São Paulo, Brazil.Os autôres estudam o pulgão Cerosipha forbesi (Weed, 1889) (= Aphis forbesi), que vive sobre o morangueiro (Fragaria spp.), inseto provavelmente ainda não assinalado na literatura entomológica brasileira

Contribuição para o conhecimento da Mimosicerya hempeli (Cockerell, 1899) (Homoptera. Margarodidae) e de seu predador Exoplectra erythrogasfer Mulsant, 1851 (Coleoptera, Coccinellidae)

This paper deals with Mimosicerya hempeli (Cock., 1899) (Homoptera, Margarodidae) and its predator, the ladybeetle Exo-plectra erythrogaster Muls., 1851 (Coleoptews, Coccinellidae), which were found to occur at Piracicaba, State of São Paulo, Brasil. The first is a pest of "cássia imperial" (Cassia fistula L.), and several other trees. As those insects are little known, a few bionomical notes and descriptions of some of their stages are presented. The adult scales proved to be very resistant to an application of mineral oil plus malathion. Methyl Demeton applied with irrigation water showed no control. The same insecticide injected into the trunk gave very poor results