Development of a Low-frequency Microphone for Measurement of Bio-signals by Mobile Phones for Ubiquitous Medical and Healthcare Monitoring

2013 ◽  
pp. 346-361
2010 ◽  
Vol 10 (5) ◽  
pp. 934-941 ◽  
Author(s):  
Kajiro Watanabe ◽  
Yosuke Kurihara ◽  
Tetsuo Nakamura ◽  
Hiroshi Tanaka

2013 ◽  
Vol 35 (3) ◽  
pp. 210-221 ◽  
Author(s):  
Carolina Calderón ◽  
Darren Addison ◽  
Terry Mee ◽  
Richard Findlay ◽  
Myron Maslanyj ◽  
...  

ReCALL ◽  
2008 ◽  
Vol 20 (3) ◽  
pp. 315-330 ◽  
Author(s):  
Claire Kennedy ◽  
Mike Levy

AbstractThis article discusses an experiment in sending regular Short Message Service (SMS) messages to support language learning, and vocabulary learning in particular, at beginners' level in Italian at an Australian university. The approach we took built on the initiatives of Thornton and Houser (2005) and Dias (2002b), and was informed by the results of an earlier trial we had conducted with students at high-intermediate level (Levy & Kennedy, 2005). In testing the possibilities for using mobile phones for language learning purposes, we were especially interested in investigating the acceptability of a ‘push’ mode of operation, in which the scheduling of messages is determined by the teachers. While the students appreciated the experience overall, and found the message content often useful or enjoyable, there was a wide range of views on the frequency of messages acceptable. We are therefore planning the further integration of messaging into the course around a flexible arrangement involving options for high or low frequency of pushed messages, as well as messages available on request – in ‘pull’ mode.


2020 ◽  
Vol 47 (9) ◽  
pp. 1094-1104
Author(s):  
Yuanwen Lai ◽  
Xinying Xu ◽  
Said M. Easa ◽  
Peikun Lian

Limited by the low-frequency data acquisition, vehicle global positioning system (GPS) data are difficult to implement in the area of microtraffic simulation. Based on the functional design of mobile phone positioning technology, mobile phones can be used to acquire bus GPS data every second. In this paper, an analytical model is proposed to determine the parameters of signal coordination for bus priority along an arterial based on GPS data of mobile phones. First, bus priority evaluation indicators are established using bus GPS data, which are acquired by mobile phones. Second, the signal timing parameters of the arterial road are optimized, and a preliminary timing plan is developed by evaluating small changes in the plan. Finally, the corresponding final plan is developed using VISSIM micro simulation software. The feasibility of the analytical model is verified by simulating an actual arterial in Fuzhou city, China.


2021 ◽  
Vol 9 ◽  
Author(s):  
Karolina Sieroń ◽  
Katarzyna Knapik ◽  
Grzegorz Onik ◽  
Ewa Romuk ◽  
Ewa Birkner ◽  
...  

Objective: The aim of the study was to assess the influence of electromagnetic fields with divergent physical properties on the prooxidative and antioxidative balances in homogenates of the tongue, salivary glands, esophagus, stomach, and small and large intestines of rats.Material and Methods: Forty rats were randomly divided into four equal groups, namely, a control group, a group exposed to low-frequency electromagnetic fields (LF-EMFs; frequency: 50 Hz; intensity: 10 kV/m; magnetic induction: 4.3 pT), a group exposed to radiofrequency electromagnetic fields (RF-EMFs) emitted by mobile phones (frequency: 900 MHz), and a group exposed simultaneously to LF-EMFs and RF-EMFs emitted by mobile phones. After 28 consecutive days of the experiment, the following pro- and antioxidative markers were assessed in the gastrointestinal tract homogenates: superoxide dismutase (SOD) and its two isoenzymes (Mn-SOD, Cu,Zn-SOD) catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione S-transferase (GST), total antioxidative capacity (TAC), total oxidative status (TOS), and malondialdehyde (MDA).Results: In rats exposed to LF-EMFs, higher concentrations of the markers of prooxidant processes, MDA or TOS, were observed in the salivary glands, esophagus, and small intestine homogenates in comparison with the control group. Additionally, in the group of rats opposite to the control, antioxidant activity was observed. The main differences included a higher activity of Cu,Zn-SOD in homogenates of the tongue, salivary glands, and esophagus as well as decreased activity of CAT in homogenates of the tongue, esophagus, and small intestine. In animals exposed to RF-EMFs, the concentration of TOS was higher in the large intestine than in control rats. The main difference of antioxidant activity was presented by decreased Cu,Zn-SOD in homogenates of the salivary glands, stomach, small and large intestine as well as CAT in homogenates of the tongue, esophagus, stomach, and small and large intestine. Moreover, in rats exposed simultaneously to LF-EMFs and RF-EMFs, a lower concentration of TOS was observed. Antioxidant activity was presented by a decreased activity of CAT in homogenates of the tongue, esophagus, stomach, and small and large intestine in comparison to the control group.Conclusion: Among those applied in the study, electromagnetic fields of a low-frequency caused the most significant disturbances of oxidative stress in the rat gastrointestinal tract.


Author(s):  
Gu-Min Jeong ◽  
Jong-Duck Lee ◽  
Sang-Il Choi ◽  
Dong-Wook Kang

This paper presents a new JPEG quantization table design method for mobile phone images. Although the screen size of mobile phones is very small, the full information of the image should nevertheless be represented. Moreover, the high frequency components of the mobile phone images may contain important information. In order to enhance the performance of mobile JPEG images, these high frequency components should be compensated using an appropriate quantization table. Considering these characteristics, we propose a modeling method of the quantization table for compensating the high frequency components of the mobile images while sacrificing their low frequency components. We select the optimized pre-emphasis factor and bias factor using various sets of 240× 320 images and show that the proposed method improves the performance in terms of size and PSNR.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
L. Zastko ◽  
L. Makinistian ◽  
A. Tvarožná ◽  
F. L. Ferreyra ◽  
I. Belyaev

AbstractWhether the use of mobile phones (MP) represents a health hazard is still under debate. As part of the attempts to resolve this uncertainty, there has been an extensive characterization of the electromagnetic fields MP emit and receive. While the radiofrequencies (RF) have been studied exhaustively, the static magnetic fields (SMF) have received much less attention, regardless of the fact there is a wealth of evidence demonstrating their biological effects. We performed 2D maps of the SMF at several distances from the screen of 5 MP (models between 2013 and 2018) using a tri-axis magnetometer. We built a mathematical model to fit our measurements, extrapolated them down to the phones’ screen, and calculated the SMF on the skin of a 3D head model, showing that exposure is in the µT to mT range. Our literature survey prompts the need of further research not only on the biological effects of SMF and their gradients, but also on their combination with extremely low frequency (ELF) and RF fields. The study of combined fields (SMF, ELF, and RF) as similar as possible to the ones that occur in reality should provide a more sensible assessment of potential risks.


Author(s):  
K. Hama

The lateral line organs of the sea eel consist of canal and pit organs which are different in function. The former is a low frequency vibration detector whereas the latter functions as an ion receptor as well as a mechano receptor.The fine structure of the sensory epithelia of both organs were studied by means of ordinary transmission electron microscope, high voltage electron microscope and of surface scanning electron microscope.The sensory cells of the canal organ are polarized in front-caudal direction and those of the pit organ are polarized in dorso-ventral direction. The sensory epithelia of both organs have thinner surface coats compared to the surrounding ordinary epithelial cells, which have very thick fuzzy coatings on the apical surface.


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