Inexpensive Electronic Devices Research Articles

3D-Printed Microfluidic Sensor for Fluorescence Measurements

In this work a fluorescent microfluidic sensor is developed, manufactured and characterized through additive manufacturing technique, using transparent photopolymer. A technology widely known as 3D printing is very suitable for tailor-made microfluidic chips, as it allows for rapid manufacturing. Optical structures can be developed using transparent materials, and this work describes a technique for increasing light transmission through such structure. A complete, inexpensive electronic device is described, containing microfluidic chip, light source, photodetector, microcontroller, communication interface and a multifunctional package with embedded connectors. Performed analyses show that performed surface modification significantly improves light transmission through structure, the material does not show autofluorescence, and whole device is suitable for fluorescence measurements.

Mobile application: donate day

Mobile application has gradually become a popular application software because it only requires inexpensive electronic devices such as mobile phones and tablets to operate. This paper therefore presents an Android mobile app application that allowed users to donate their items to charitable organizations in Malaysia. The study adopted quantitative research to study people’s behavior towards charitable donation and gathered opinion on the mobile donation app. The survey was conducted online with samples of 20 respondents. The paper also adopted the Rapid Application Development (RAD) approach to develop this mobile app’s system. The RAD approach enabled the development of the mobile app prototype to be completed quickly and enabled end users to test the mobile app to provide recommendations and make changes easily. The results of the system tests indicated that the mobile app achieved the goals of the study, but the respondents also responded to several improvements needed for the prototype.

Introducing power monitoring units for distribution networks

Power monitoring units are inexpensive devices used to monitor distribution networks. In order to select and maintain power monitoring systems for a distribution network, it is important to understand some basic facts about the devices. This article categorizes power monitoring systems available today and highlights their relative strengths and weaknesses. Inexpensive electronic devices may be installed at customer premises to monitor low-voltage electric supply, using the customer's phone line to communicate with the master station. >

Simple and Inexpensive Electronic Device for Automatic Recording and Analysis of Insect Acoustical Activity

An apparatus has been developed for monitoring the timing and duration of cricket calling song, using a simple electronic device coupled to an Apple II microcomputer. The calling activity of up to three insects can automatically be recorded and stored to magnetic disc. An analysis program determines the percent of time spent calling for each half-hour block of a 24-hour recording period. A graphical representation of the temporal pattern of calling is also an available option. Other microcomputers can be used with minor modification of the connections, and the ancillary electronics required for this purpose are inexpensive and readily constructed.

Phase relations of oscillatory contraction cycles inPhysarumplasmodia: I. a serial infrared registration device and its application to different plasmodial stages

Abstract A new and inexpensive electronic device is described which enables serial registrations of the oscillatory contraction activities at closely neighbouring sites within plasmodia of Physarum polycephalum. At the same time, this new construction allows the immediate automatic transformation of the original sinusoidal contraction curves into multiple phase graphs. The application on different stages of plasmodia reveals phase gradients as a characteristic phenomenon especially in isolated objects. The investigation of plasmodial strands without endoplasm demonstrates that the radial activities represent active contractile phenomena of the ectoplasmic tube.

An inexpensive electronic device for measuring electroantennogram responses to sex pheromone components with a voltmeter

ABSTRACT. An inexpensive, portable device which allows measurement of electroantennogram (EAG) maximum amplitudes with a voltmeter instead of an oscilloscope is described. Potential advantages of the device include more rapid recording, low‐cost construction of additional EAG recording systems for a laboratory with several users, and portability allowing studies in the field and occasional bench top use. The device is intended for use in conventional EAG recording, where EAG signals with rapid depolarizations are being measured, and where the maximum amplitude of the EAG signal is the only parameter of interest.

Oscillating contractions in protoplasmic strands of Physarum: Infrared reflexion as a non-invasive registration technique

An inexpensive electronic device employing a miniaturised infrared reflection detector is described which enables the automatic registration of intrinsic radial contraction activities of protoplasmic strands of Physarum growing on their original substrate. Advantages and shortcoming of the new registration technique are discussed in relation to recent tensiometric techniques applied to protoplasmic strands for analysing the contraction physiology of cytoplasmic actomyosins, the force generating substrate of the contraction automaticity in the Physarum system.

An automatic level controller and indicator with gating for liquid nitrogen

A simple and inexpensive electronic device is described, which can measure, indicate and control the level of liquid nitrogen in Dewar vessels to within adjustable limits. It uses several germanium diodes in series as the level sensing element to give an almost proportional control of the cryofluid. The mechanism of control can be gated and monitored by other electronic systems.

Clinical evaluation and correction of carotid artery occlusive disease: Use of the Doppler ultrasonic flowmeter

The Doppler ultrasonic flowmeter is used routinely as a screening device to detect the presence of extracranial arterial occlusive lesions. Intraoperatively it is used to grade stenotic lesions in extracranial arterial vascular lesions and to objectively evaluate the efficacy of the surgical removal of the lesion by determining vascular patency in the immediate postoperative period. The instrument is also used to assure the surgeon that no compromise of the lumen has been made at arteriotomy closure.Postoperative follow-up study with the Doppler flowmeter in the clinic enables the surgeon to atraumatically evaluate patency of the extracranial vessels without the associated morbidity of angiography.The Doppler flowmeter is a relatively inexpensive electronic device which is portable and battery-operated. Use of the instrument in the clinical setting effects a saving of time and money to both the patient and hospital while providing an objective atraumatic evaluation of vascular patency.

A correlator of time intervals between pulses.

In neurophysiological studies, it is frequently advantageous to ascertain various time relationships between neuronal discharges, or spikes. During the course of the Applied Physics Laboratory's endeavors in the field of neuronal studies, a particular need arose for a means of determining some of these time relationships. To meet this need, a relatively inexpensive electronic device was designed and built at the laboratory. This paper is a description of the device's capabilities, limitations, some of its more common functional uses, and circuitry. The application, while referenced to neuronal discharges, may be with respect to a number of pulse waveforms.