Portable Electronic System Research Articles

Preventing false spirometry values and invalid symptom scores in respiratory clinical trials

Rationale Since subjects in clinical trials using paper reporting media have been shown to transcribe invented spirometry readings and to fill in diary cards erroneously, incompletely, and at invalid times (both retrospectively and prospectively), we have developed and tested electronic methods to capture data directly from spirometers and to force timely and complete entry of self reported outcome data in clinical research. Methods Handheld computers were programmed to accept symptom data only during the time periods specified in the protocol (morning and evening, each day). The handhelds also required complete, “in-range”, and legible values. An electronic spirometer and a physiological activity sensor were fitted with short-range (15 ft) wireless circuits to transmit data samples and timestamps directly to the handheld device for inspection, acceptance and integration into patient reported symptom scores. Results Subjects without computer expertise were able to complete daily diaries and to send both subjective and physiological data daily to a secure central computer. The system successfully prevented false and inappropriately timed data while delivering completion compliance in excess of 80% of the expected reports. Conclusions A portable electronic monitoring system can prevent commonly occurring errors in timing, accuracy, completeness and legibility of data provided by subjects in respiratory clinical research.

필드 스크린을 위한 휴대용 전자코 시스템의 구현

There is currently much interest in the development of instruments that emulate the senses of humans. Increasingly, there is demand for mimicking the human sense of smell, which is a sophisticated chemosensory system. An electronic nose system is applicable to a large area of industries including environmental monitoring. We have designed a protable electronic nose system using an array of commercial chemical gas sensors for recognizing and analyzing the various odours. In this paper, we have implemented a portable electronic nose system using an array of gas sensors for recognizing and analyzing VOCs (Volatile Organic Compounds) in the field. The accuracy of a portable electronic nose system may be lower than an instrument such as GC/MS (Gas Chromatography/Mass Spectrometer). However, a portable electronic nose system could be used on the field and showed fast response to pollutants in the field. Several different algorithms for odours recognition were used such as BP (Back-Propagation) or LM-BP (Levenberq-Marquardt Back-Propagation). We applied RBF (Radial Basis Function) Network for recognition and quantifying of odours, which has simpler and faster compared to the previously used algorithms such as BP and LM-BP.

A model for battery lifetime analysis for organizing applications on a pocket computer

A battery-powered portable electronic system shuts down once the battery is discharged; therefore, it is important to take the battery behavior into account. A system designer needs an adequate high-level battery model to make battery-aware decisions targeting the maximization of the system's online lifetime. We propose such a model that allows a designer to analytically predict the battery time-to-failure for a given load. Our model also allows for a tradeoff between the accuracy and the amount of computation performed. The quality of the proposed model is evaluated using typical pocket computer applications and a detailed low-level simulation of a lithium-ion electrochemical cell. In addition, we verify the proposed model against actual measurements taken on a real lithium-ion battery.

Portable electronic nose system with gas sensor array and artificial neural network

A portable electronic nose system has been fabricated and characterized using an oxide semiconductor gas sensor array and artificial neural network. The sensor array consists of such thick-film oxide semiconductor sensing materials as Pd-doped WO 3, Pt-doped SnO 2, TiO 2–Sb 2O 5–Pd-doped SnO 2, TiO 2–Sb 2O 5–Pd-doped SnO 2+Pd-coated layer, Al 2O 3-doped ZnO and PdCl 2-doped SnO 2. The portable electronic nose system consists of an Intel 80c196kc as CPU, an EEPROM and an LCD for displaying gas concentrations, etc. As an application, the system has been used to identify 26 CO/HC car exhausting gases and the identification has been successfully demonstrated.

Portable digital electronic radiography system with a solid-state area-imaging detector

A digital system for radiographic inspection was constructed in a portable version suitable for field use. The system uses typical film radiography sources, including 60Co, 192Ir and X-ray generators. Radiographic images are formed using an area-imaging scintillating detector coupled to a charge-coupled device camera and a portable industrial computer. Compared to film radiography, this technology offers imaging without wet-film processing, shorter exposure times, larger dynamic range, and digital imaging that permits compact archiving, easy data access and mathematical image processing to improve sensitivity. System performance is illustrated for typical applications, i.e., for radiographing valves and pipes. Using 192Ir, the system works well on smaller water-filled valves and pipes; larger valves have to be drained. Work is under way to address this problem.

Feasibility study of a portable PIXE system using a 210Po alpha source

An alpha source which consists of 1 mCi of 210Po electro-deposited on 1 μm thin Ag foil attached to a ceramic backing has been prepared. The overall geometry exhibits a truncated-conical shape. The source has been coupled to a standard 10 mm diameter Si(Li) X-rays detector connected to a portable electronic system (ORTEC-NOMAD). The analysed area of the exposed samples is 16 mm in diameter. Preliminary results state that medium-light elements, like Ca, Ti, Fe, Co, Cr, Ni and Cu can be easily analysed at concentrations of some per cent. Lighter elements determination is affected by the enhancing presence of X-rays generated in the Ag foil and by some chlorine impurities. PIXE measurements of attic greek pottery sherds are discussed.

A High Resolution Electronic Imaging System for Crime Scene Use

Abstract A portable high resolution electronic imaging system has been designed and built for recording laser or ultraviolet excited fluorescent marks at serious crime scenes. A 2048 × 2048 pixel Peltier cooled CCD camera and PC-based image capture system contained in two flight cases forms the basis of the system. The captured images can be viewed at the scene to ensure recording quality and returned to the Laboratory stored on magneto optical disks for hardcopy production or digital image processing.

A portable electronic system for radiation dosimetry using electrets

An electret dosimeter with a cylindrical active volume has been introduced by Mascarenhas and collaborators [Proc. 10th Anniversary Conf. 1969–1979, Associacâo Brasileira de Fisicos em Medicina, p. 488; Topics Appl. Phys. 33 (1987) 321] for possible use in personnel and area monitoring. The full energy response curve as well as the degree of reproducibility and accuracy of the dosimeter are reported in a previous report [O. Guerrini, Master Science Thesis, São Carlos, USP-IFQSC (1982)]. For dimensions similar to those of the common pen dosimeter, the electret has a total surface charge of the order of 10 −9 C and it has a readout sensitivity of the order of 10 −5 Gy with a useful range of 5 × 10 −2 Gy. In this paper we describe a portable electronic system to measure X and γ-rays using a cylindrical electret ionization chamber. It uses commercially available operational amplifiers, and charge measurements can also be made by connecting a suitable capacitor in the feedback loop. With this system it is possible to measure equivalent surface charges up to (19.99±0.01) on the dosimeter. The readout doses are shown on a 3 1 2 digit liquid crystal display (LCD). We have used complementary metal oxide semiconductor (CMOS) and bipolar metal oxide semiconductor (BiMOS) operatonal amplifier devices in the system's design. This choice provides small power consumption and is ideal for battery powered instruments. Furthermore the instrument is ideally suited for in situ measurements of X and γ radiation using a cylindrical electret ionization chamber.

Most recent developments in the field of optical and electronic visual aids for severely visually handicapped and blind patients

Magnifying spectacles represent one of the indispensable optical aids (Keplerian systems having surpassed Galilean systems during the last years), closed-circuit television, Optacon, and navigating aids based on ultrasound as environmental sensors. -None of the other navigating aids have proved useful. Initial successes have, however, been achieved with a miniature hand-held camera for closed-circuit television and a portable electronic reading system (View-Scan). Genuine progress has been made with the braille information storage systems, which utilize computer technology to store texts which have been read and written, and subsequently to print them or reproduce them on a screen or in synthetic language. Braillex in the Federal Republic of Germany and Versabraille in the U.S.A. are examples of such systems. In special cases a newly developed stereo photocopy system (Minolta) will be useful for newly blinded adults. However, texts in the form of tactile copies have to be highly magnified in order to be palpable and readable.

A portable spark-chamber range spectrometer and data acquisition system

A portable spark-chamber range spectrometer and electronic data acquisition system is described for acquiring spectral data on energetic charged particles. The instrument system consists of a uni-directional spark-chamber range telescope with pulse-height analysis of the specific energy loss ( dE dx of a charged particle that passes through a triggering telescope. The range telescope consists of a stack of sealed double-gap spark-discharge modules with absorbers sandwiched between them. A Cherenkov counter discriminates against electrons and muons. Cherenkov and dE dx signals are gated by the coincidence circuit. Data, either telemetered or recorded in situ, include the number of coincidences, a clock signal, system voltage levels, and the dE dx , Cherenkov, and spark-discharge module signals. Power consumption of the self-contained system is about 10 W at an event rate of 20 per second and 17 W at an event rate of 100 per second. The standby power is about 8 W. This instrument system can measure primary protons and alphas at balloon altitudes and secondary protons at lower altitudes. A particular configuration with a geometric factor of about 1 cm 2 sr has been assembled for measuring atmospheric proton intensities and spectra in the range from MeV to 300 MeV and at altitudes ranging from the altitude of high-flying aircraft to balloon altitudes near the top of the atmosphere.

Electronic transducer for rumination research.

A reliable, inexpensive, and portable electronic instrumentation system for monitoring small physiological movements of animals has been designed, developed and tested. In its application for monitoring chew rate in rumination studies, a bellows pneumograph and a miniature solid-state electronic transducer mounted on the animal's halter convert jaw movement into a pneumatic and then electrical signal for convenient data transmission, processing and storage on an event recorder. Operation of the monitoring system with less than ½% error has been experimentally verified over an input movement-frequency range to ¼ to 16 cycles/sec, a temperature range of −18 C to 65 C, and an input electrical supply as low as 93 VAC. Proper operation of the transducer module of the system has been shown to be independent of orientation over this range of test variables. Presently, the instrumentation system has been successfully used as a chew-rate monitor for approximately 1,400 steer-hr in feeding tests. Sufficient design and construction details are presented herein to permit local fabrication of an eight-channel monitor.

A Portable Electronic Multichannel Dendrograph and Environmental Factor Recording System

A sensitive low-cost device for measuring and recording tree diameter growth, temperature, or other environmental parameters is described. An example of temperature–diameter traces for a 5-day period in early winter is presented and the nature of the diurnal cycle of diameter change during the growing season is discussed.

A note on the ductility of beryllium single crystals oriented for basal slip and tested in tension

A portable spark-chamber range spectrometer and electronic data acquisition system is described for acquiring spectral data on energetic charged particles. The instrument system consists of a uni-directional spark-chamber range telescope with pulse-height analysis of the specific energy loss (dEdx of a charged particle that passes through a triggering telescope. The range telescope consists of a stack of sealed double-gap spark-discharge modules with absorbers sandwiched between them. A Cherenkov counter discriminates against electrons and muons. Cherenkov and dEdx signals are gated by the coincidence circuit. Data, either telemetered or recorded in situ, include the number of coincidences, a clock signal, system voltage levels, and the dEdx, Cherenkov, and spark-discharge module signals. Power consumption of the self-contained system is about 10 W at an event rate of 20 per second and 17 W at an event rate of 100 per second. The standby power is about 8 W. This instrument system can measure primary protons and alphas at balloon altitudes and secondary protons at lower altitudes. A particular configuration with a geometric factor of about 1 cm2 sr has been assembled for measuring atmospheric proton intensities and spectra in the range from MeV to 300 MeV and at altitudes ranging from the altitude of high-flying aircraft to balloon altitudes near the top of the atmosphere.