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Portable Devices (portable + device)
Selected AbstractsThe future for in-vehicle information systems: The technology and its impactsJOURNAL OF ADVANCED TRANSPORTATION, Issue 3 2002Michael G H Bell In-vehicle information has an important social role to play in improving the efficiency and safety of travel by all modes. In this review, three generations of system are identified. The first generation consists of simple in-vehicle units relying heavily on external data. The second generation has more sophisticated in-vehicle units with colour TFT screens and DVD players for maps and entertainment. The third generation again makes use of external data, using the mobile phone network to download map sections and other data as and when required, thereby obviating the need for beacons and map CDs. For locationing, GPS (and/or Galileo, the European version of GPS) remains the favoured technology. Portable devices offering multi-modal information could improve inter-modal transport efficiency. [source] Direct toxicity assessment of wastewater: Baroxymeter, a portable rapid toxicity device and the industry perspectiveENVIRONMENTAL TOXICOLOGY, Issue 3 2002Achilles Tzoris Abstract Direct toxicity assessment of wastewater is becoming necessary, and new legislation may render it compulsory for the water industry. At present such assessment is performed at a laboratory away from a site, at considerable cost, and results often come too late, after a toxic event has occurred and the toxin has been released into the environment. Some of the rapid toxicity tests available today require certain conditions to function properly, or their results do not always correlate with other methods. The objective of this study was to assess a portable device, the Baroxymeter, for its suitability as an instrument to test wastewater toxicity. The way the device works is based on monitoring respiration of a bacterial culture by pressure measurements and using respiration inhibition as a toxicity alert. It has been shown that it is possible to detect toxic substances such as 3,5-dichlorophenol and bronopol within 5 min from a 1-mL sample. The benefits and future applications of the Baroxymeter as a high-throughput, cost-effective alternative for toxicity screening are discussed in this article. © 2002 Wiley Periodicals, Inc. Environ Toxicol 17: 284,290, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/tox.10059 [source] Obstructive Sleep Apnea in a Clinical Series of Adult Epilepsy Patients: Frequency and Features of the ComorbidityEPILEPSIA, Issue 6 2003Raffaele Manni Summary: Purpose: The aim of this study was to evaluate the rate and features of obstructive sleep apnea (OSA) in adult epilepsy patients. Methods: Two hundred eighty-three adult epilepsy patients (137 men; mean age, 33 years; range, 18,70 years) were prospectively screened for OSA by means of a structured interview. Those in whom OSA was clinically suspected were monitored for a full night by using a portable device (Polymesam), and OSA was diagnosed when they had an Apnea/Hypopnea Index greater than five. Results: Coexistence of OSA with epilepsy was found in 10.2% (15.4% of the male and 5.4% of the female) epilepsy patients investigated. The OSA was mild in 66.6%, moderate in 22.2%, and severe in 11.1% of the cases. The "epilepsy + OSA" patients were older, heavier, more frequently male, and sleepier (p < 0.05) than those with "epilepsy only." Furthermore, they experienced their first seizure at an older age (p < 0.05). Conclusions: Systematic investigation reveals that OSA is frequent in epilepsy patients. The major risk factors for OSA in our epilepsy patients were the same as those typically found in the general population. Of the epilepsy-related factors, older age at onset of seizures appears to be significantly related to comorbidity with OSA (p < 0.05). The presence in epilepsy patients of these features should alert the clinician to the possibility of an underlying OSA. [source] QUARTZ-TUNGSTEN-HALOGEN AND LIGHT-EMITTING DIODE CURING LIGHTSJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 3 2006Kraig S. Vandewalle DDS Curing lights are an integral part of the daily practice of restorative dentistry. Quartz-tungsten-halogen (QTH), plasma-arc (PAC), argon laser, and light-emitting diode (LED) curing lights are currently commercially available. The QTH curing light has a long, established history as a workhorse for composite resin polymerization in dental practices and remains the most common type of light in use today. Its relatively broad emission spectrum allows the QTH curing light to predictably initiate polymerization of all known photo-activated resin-based dental materials. However, the principal output from these lamps is infrared energy, with the generation of high heat. Filters are used to reduce the emitted heat energy and provide further restriction of visible light to correlate better with the narrower absorbance spectrum of photo-initiators. The relatively inefficient emission typically requires corded handpieces with noisy fans. PAC lights generate a high voltage pulse that creates hot plasma between two electrodes in a xenon-filled bulb. The irradiance of PAC lights is much higher than the typical QTH curing light, but PAC lights are more expensive and generate very high heat with an inefficient emission spectrum similar to that of QTH bulbs. Light emitted from an argon laser is very different from that emitted from the halogen or PAC lights. The photons produced are coherent and do not diverge; therefore, lasers concentrate more photons of specific frequency into a tiny area. With very little infrared output, unwanted heat is minimized. However, argon lasers are very expensive and inefficient due to a small curing tip. LED curing lights have been introduced to the market with the promise of more efficient polymerization, consistent output over time without degradation, and less heat emission in a quiet, compact, portable device. This review evaluates some of the published research on LED and QTH curing lights. [source] The determinants of Canadian children's personal exposures to magnetic fieldsBIOELECTROMAGNETICS, Issue 3 2001Ben G. Armstrong Abstract Study of the health effects of magnetic fields often depends on identifying determinants and hence indicators of personal exposure. This study identified determinants of children's exposure to magnetic fields and constructed a prediction model for them. For 632 children participating in a case,control study of childhood leukemia, we made direct measures of exposure over 48,h using a portable device, together with observations on candidate determinants. A child's age and sex, the proportion of time spent in the home, and their parents' education or income were very weak predictors of (logged) mean 48,h magnetic field (R2,<,1%). More important were province (R2,=,8.0%) and type of residence (R2,=,11.3%). Low temperatures at the time of measurement were associated with high fields (about 20% increase for each 10°C below 14, R2,=,4.9%). Several visible attributes of wiring around residences predicted exposure, mostly captured in the Wertheimer-Leeper wire code (R2,=,13.5%). Stationary 24,h measurement in the bedroom (R2,=,63.3%) and spot measurements outside the house (R2,=,40.7%) predicted personal exposures best. Adding other minor predictors increased only slightly variance explained by 24,h stationary (R2,=,66.2%) and spot (R2,=,46.8%) measurements. Without spot or stationary measurements, the best model was much less powerful (R2,=,29.0%). We conclude that spot measurements outside the residence provide a moderately effective basis for estimating exposure for children living there, but do not perform as well as 24,h stationary measurements in the child's bedroom. Although several other easily-observed variables were associated with personal exposure, they were weak determinants, either individually or in combination. Bioelectromagnetics 22:161,169, 2001. © 2001 Wiley-Liss, Inc. [source] A novel miniature monopole tag antenna for passive UHF RFID applicationsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 12 2010Hsien-Wen Liu Abstract A novel miniature monopole tag antenna for passive Ultra-High Frequency (UHF) radio frequency identification (RFID) operation is presented. The antenna possesses a two-sided structure that is printed on an FR4 substrate and fed by a 50-, microstrip line. By properly using helical strips and vias, the antenna size can be reduced to a small volume of 10 (L) × 9.5 (W) × 0.8 (H) mm3 to be easily integrated within various portable devices. A miniaturized quasi-lumped circuit is also designed to attain a good impedance matching between the antenna and the chip. Experimental results demonstrate that the antenna has a suitable operating band about 914,939 MHz and also quite omnidirectional radiation pattern with appreciable gain. Moreover, the proposed compact tag antenna, capable of achieving a maximum readable range of about 5.6 m with an EIRP equal to 4 W, is well suited for RFID applications. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2770,2772, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25596 [source] Novel planar triple band monopole antenna for WiMAX/WLAN applicationsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 11 2010Hsien-Wen Liu Abstract A coplanar waveguide (CPW)-fed planar monopole antenna with triple band operation for worldwide interoperability for microwave access (WiMAX) and wireless local area network (WLAN) applications is presented. The antenna, which occupies a small size of 25 (L) × 25 (W) × 0.8 (H) mm3, is simply composed of a pentagonal radiating patch with two bent slots. By carefully selecting the positions and lengths of these slots, good dual stopband rejection characteristic of the antenna can be obtained, so that three operating bands covering 2.14,2.85, 3.29,4.08, and 5.02,6.09 GHz can be achieved. The measured results also demonstrate that the proposed antenna has good omnidirectional radiation patterns with appreciable gain across the operating bands, and is thus suitable to be integrated within the portable devices for WiMAX/WLAN applications. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2405,2408, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25497 [source] The high isolation dual-band inverted F antenna diversity system with the small N-section resonators on the ground planeMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 3 2007Ki-Jin Kim Abstract The high isolated dual-band inverted-F diversity systems for portable devices, operating in 2.4 GHz band (2400,2484 MHz) and 5.2 GHz band (5150,5350 MHz), are presented. To reduce the mutual coupling and get high isolation between two internal dual-band antennas, we proposed the small N-section resonators in the form of slots on the ground plane. The optimized small size resonators for high isolation, antenna radiation efficiency, and high effective diversity are analyzed. Because of their small size, N-section resonators can be widely used in small diversity systems that require high isolation between antennas. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 731,734, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22238 [source] Optimal Pressure Regulation of the Pneumatic Ventricular Assist Device With Bellows-Type DriverARTIFICIAL ORGANS, Issue 8 2009Jung Joo Lee Abstract The bellows-type pneumatic ventricular assist device (VAD) generates pneumatic pressure with compression of bellows instead of using an air compressor. This VAD driver has a small volume that is suitable for portable devices. However, improper pneumatic pressure setup can not only cause a lack of adequate flow generation, but also cause durability problems. In this study, a pneumatic pressure regulation system for optimal operation of the bellows-type VAD has been developed. The optimal pneumatic pressure conditions according to various afterload conditions aiming for optimal flow rates were investigated, and an afterload estimation algorithm was developed. The developed regulation system, which consists of a pressure sensor and a two-way solenoid valve, estimates the current afterload and regulates the pneumatic pressure to the optimal point for the current afterload condition. Experiments were performed in a mock circulation system. The afterload estimation algorithm showed sufficient performance with the standard deviation of error, 8.8 mm Hg. The flow rate could be stably regulated with a developed system under various afterload conditions. The shortcoming of a bellows-type VAD could be handled with this simple pressure regulation system. [source] Ion-Exchange Plasma Membranes for Fuel Cells on a Micrometer Scale,CHEMICAL VAPOR DEPOSITION, Issue 6-7 2007S. Roualdès Abstract Recent advances in,miniaturization technology make polymer electrolyte membrane fuel cells very attractive as power sources for portable devices. Ion-exchange membranes for microscale fuel cells are synthesized by plasma polymerization (using a precursor containing ion-exchange groups) and intensively characterized. Ion-exchange plasma membranes are thin, amorphous, and dense materials with no defects. Spectroscopic analyses reveal a polymer-type matrix containing a rather high concentration of ion-exchange groups. Under the best synthesis conditions, membranes show a satisfying ionic conduction level and a high compatibility with other active layers of fuel cells, making them suitable for insertion in such power-supply devices. [source] | |||||||||||||