Midwives’ Perceptions Regarding the Use of the Cardiotocograph Machine as an Intrapartum Monitoring Tool in Namibia: A Qualitative Research Study

Although, at the time of this study, the cardiotocograph machine was the acceptable monitoring tool to be used intrapartum, its appropriate use was a matter of concern for midwives globally. This article reports the findings of a qualitative study which investigated the perceptions of midwives, who were working in a labor ward in a public referral hospital in Namibia, regarding the use of the cardiotocograph machine. The objectives of the study included: to explore and describe the perceptions of midwives working in a labor ward in Namibia regarding the use of the cardiotocograph machine as a labor monitoring tool; and to explore and describe how midwives working in a labor ward in Namibia perceived informing women who were in labor about the use of the cardiotocograph machine as a labor monitoring tool. The study site was a public referral hospital which offered services to the five northern regions of Namibia. The requisite data was collected using semi-structured, one-on-one interviews which were conducted with seventeen (17) purposively selected participants. The interviews were recorded on an audio device. The spiral method of data analysis was adopted. The study findings revealed that the participants had varying perceptions on the use of the cardiotocograph machine intrapartum and, as such, perceived its use as a challenge. It was concluded that midwives need to be empowered via refresher courses with regard to the use of cardiotocograph machine to ensure optimum results.

Fall Detection via Inaudible Acoustic Sensing

The fall detection system is of critical importance in protecting elders through promptly discovering fall accidents to provide immediate medical assistance, potentially saving elders' lives. This paper aims to develop a novel and lightweight fall detection system by relying solely on a home audio device via inaudible acoustic sensing, to recognize fall occurrences for wide home deployment. In particular, we program the audio device to let its speaker emit 20kHz continuous wave, while utilizing a microphone to record reflected signals for capturing the Doppler shift caused by the fall. Considering interferences from different factors, we first develop a set of solutions for their removal to get clean spectrograms and then apply the power burst curve to locate the time points at which human motions happen. A set of effective features is then extracted from the spectrograms for representing the fall patterns, distinguishable from normal activities. We further apply the Singular Value Decomposition (SVD) and K-mean algorithms to reduce the data feature dimensions and to cluster the data, respectively, before input them to a Hidden Markov Model for training and classification. In the end, our system is implemented and deployed in various environments for evaluation. The experimental results demonstrate that our system can achieve superior performance for detecting fall accidents and is robust to environment changes, i.e., transferable to other environments after training in one environment.

Wireless Power Hanger Pad for Portable Wireless Audio Device Power Charger Application

Since the portability feature has been introduced in headphone development, this device now uses a battery as the main built-in power. However, the battery has limited power capacity and a short lifetime. Battery substitution and a conventional battery charger method is an ineffective, inflexible inconvenience for enhancing the user experience. This paper presents an innovative portable audio device battery built-in charger method based on wireless power technology. The developed charging device is composed of a headphone hanger pad for the wireless headphone and a charging pad for the portable wireless audio device battery charging. Circular flat spiral air-core coil was designed and evaluated using a numerical method to obtain optimal vertical magnetic field distribution based on the proposed evaluation criteria. A coil has inner coil diameter of 25 mm, outer coil diameter of 47.8 mm, wire diameter of 0.643 mm, the pitch of 0.03 mm and a number of turns of 17 was chosen to be implemented on the transmitter coil. A magnetic induction technique was adopted in the proposed wireless power transmission module which was implemented using commercial off-the-shelf components. For experimental and validation purposes, a developed receiver module applied to the commercial wireless headphone and portable audio speaker have a built-in battery capacity at 3.7 V 300 mAh. The experimental results show that the wireless power hanger pad prototype can transfer a 5 V induction voltage at a maximum current of 1000 mA, and the power transfer efficiency is around 70%. It works at 110 kHz of operation frequency with a maximum transmission distance of about 10 mm and takes 1 h to charge fully one 3.7 V 300 mAh polymer lithium battery.

USB (Universal Serial Bus)

USB device dibagi menjadi beberapa golongan kelas seperti Human Interface Device, Communication Device, Mass Strorage Device, Audio Device, Printing Device, dan lain sebagainya. Windows sebagai system operasi telah mengembangkan dan meningkatkan pelayanan kepada berbagai macam USB Device, terutama pada HID class device. perkembangan terkahir menunjukan bahwa Windows telah menangani HID USB device dengan baik. Dengan menggunakan interface Universal Serial Bus, maka sebuah UPS dengan Class HID dan subclass Power Device memiliki peluang yang sangat besar untuk diinterfacekan dengan Power Management pada system windows.

Electromechanical cell lysis using a portable audio device: enabling challenging sample preparation at the point-of-care

Portable lysis of Mycobacterium marinum and Staphylococcus epidermidis bacteria using an mp3 player, electromagnetic coil, and magnet in a tube.

HRTF Adjustments with Audio Quality Assessments

There are an increasing number of binaural systems embedded with head-related transfer functions (HRTFs), so listeners can experience virtual environments via conventional stereo loudspeakers or head- phones. As HRTFs vary from person to person, it is difficult to select appropriated HRTFs from already existing databases for users. Once the HRTFs in a binaural audio device hardly match the real ones of the users, poor localization happens especially on the cone of confusion. The most accurate way to obtain personalized HRTFs might be doing practical measurements. It is, however, expensive and time consuming. Modifying non-individualized HRTFs may be an effort-saving way, though the modifications are always accompanied by undesired audio distortion. This paper proposes a flexible HRTF adjustment system for users to define their own HRTFs. Also, the system can keep sounds from suffering intolerable distortion based on an objective measurement tool for evaluating the quality of processed audio.

Intelligent Control Network Design for Audio Equipment

In order to solve the problem of inconvenience in network construction, short transmission distance of RS232 and non-intelligence audio device with different interface for network, this paper presented a design of audio intelligent control network based on CAN-Bus. The topology of audio control network, structured models of ICANNet and hardware are firstly discussed. Then the protocol of transport layer and application layer and software of intelligent control network is studied. Finally the test results were given to demonstrate the feasibility and reliability of the design.