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Sertraline-Associated Urinary Incontinence in an Adolescent with Obsessive-Compulsive Disorder: A Case Report and Literature Review
(2024-07-01)
Phiphopthatsanee, Nacharin
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Therdyothin, Atiporn
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Monitoring of equatorial plasma bubbles using aeronautical navigation system: a feasibility study
(2023-12-01)
Hosokawa, Keisuke
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Saito, Susumu
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Nakata, Hiroyuki
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Lin, Chien Hung
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Lin, Jia Ting
It has long been known that field-aligned irregularities within equatorial plasma bubbles (EPBs) can cause long-range propagation of radio waves in the VHF frequencies such as those used for TV broadcasting through the so-called forward scattering process. However, no attempt has been made to use such anomalous propagations of VHF radio waves for wide-area monitoring of EPBs. In this study, we investigated the feasibility of monitoring of EPBs using VHF radio waves used for aeronautical navigation systems such as VHF Omnidirectional radio Range (VOR). There are 370 VOR stations in the Eastern and Southeastern Asian region that can be potentially used as Tx stations for the observations of anomalous propagation. We have examined the forward scattering conditions of VHF waves using the magnetic field model and confirmed that it is possible to observe the EPB-related anomalous propagation if we set up Rx stations in Okinawa (Japan), Taiwan, and Thailand. During test observations conducted in Okinawa since 2021, no signal has been received that was clearly caused by anomalous propagation due to EPBs. This is simply because EPBs have not developed to high latitudes during the observation period due to the low solar activity. In March 2023, however, possible indications of EPB-related scattering were detected in Okinawa which implies the feasibility of observing EPBs with the current observation system. We plan to conduct pilot observations in Taiwan and Thailand in future to further evaluate the feasibility of this monitoring technique. Graphical Abstract: [Figure not available: see fulltext.]
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Enhancement of sensing characteristics of Polydimethylsiloxane-based capacitive force sensor by introducing conductive polymer to dielectric layer
(2021-01-01)
Siangkhio, Yasumin
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Rangkasikorn, Adirek
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Tammarugwattana, Narin
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Kayunkid, Navaphun
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Jessadaluk, Sukittaya
A capacitive force sensor is one of the electronics components used in several electronic devices and applications. An improvement of sensing characteristics of the sensor, for example sensitivity and response time, becomes an interesting research topic. The alternative approach to enhance the sensitivity and response time of polydimethylsiloxane-based capacitive force sensors is proposed by introducing poly(3,4-ethylenedioxythiophene) polystyrene sulphonate, a conductive polymer, into polydimethylsiloxane active layer. Two sensors using different active layers, (i) polydimethylsiloxane (conventional sensor) and (ii) poly(3,4-ethylenedioxythiophene) polystyrene sulphonate mixed polydimethylsiloxane (modified sensor), were fabricated and characterised to reveal the sensing enhancement. Interestingly, the modified sensor shows the significant increase in the sensitivity from 0.7 to 1.14 kPa<sup>–1</sup> (+62.86%) and the shortening response time from 1.55 to 0.43 s (−72.26%) with respect to the conventional sensor. In addition, the deterioration in elastic behaviour and the faster charge–discharge behaviour observed from the poly(3,4-ethylenedioxythiophene) polystyrene sulphonate mixed polydimethylsiloxane film indicate the better deformation and charge transport than that from polydimethylsiloxane film. Therefore, it can be concluded that the conductive poly(3,4-ethylenedioxythiophene) polystyrene sulfonate additive plays the role of mechanical and electrical modification of the polydimethylsiloxane active layer leading to the enhancement in sensitivity and response time of the polydimethylsiloxane-based capacitive force sensor.
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Response to comments on the paper, “Effect of low thermal treatment temperatures on the morphological, optical and electrical properties of Sn1-xMnxTe nanocomposite films incorporated with indium cations [Ceram. Int. 45 (2019) 23,203–23215]”
(2020-08-15)
Rukcharoen, Nuengruethai
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Tubtimtae, Auttasit
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Vailikhit, Veeramol
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Teesetsopon, Pichanan
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Kitisripanya, Nareerat
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Heat transfer in turbulent tube flow inserted with loose-fit multi-channel twisted tapes as swirl generators
(2017-11-01)
Kunlabud, Suttisak
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Chuwattanakul, Varesa
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Kongkaitpaiboon, Vichan
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Promthaisong, Pitak
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Eiamsa-ard, Smith
Heat transfer and flow behaviors in three-dimensional circular tubes with loose-fit multiple channel twisted tapes were numerically studied. The investigation was examined for Reynolds numbers (Re) ranging from 5000 to 15,000, by using air as testing fluid. Effects of the multiple channel number (N=2,3, and 4), clearance ratio (CR=0.0, 0.025, 0.05, and 0.075) on heat transfer enhancement and flow friction were examined. The numerical results indicate that the tubes with loose-fit multiple channel twisted tapes perform higher heat transfer rates than the plain tube. The enhanced heat transfer rate is escorted with larger pressure drop. Both heat transfer and pressure drop increase with increasing multiple channel number (N) and decreasing clearance ratio (CR). Heat transfer augmented by the loose-fit multiple channel twisted tape with N=4 is higher than those enhanced by the ones with N=2 and 3 by around 9.5–17.8% and 5.8–7.8%, respectively. In addition, the loose-fit multiple channel twisted tapes with clearance ratio of 0.025, 0.05, and 0.075 give lower heat transfer rates than the one with CR=0.0 by around 8.4%, 17.5%, and 28.8%, respectively.
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New current-voltage transferring device with different metals
(2015-09-01)
Kando, Masaaki
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Pattanadech, Norasage
A new concept of an electrical shunt with different materials (aluminum and copper) has been developed to be used as an alternative current measurement device. The device provides better current measurement characteristics compared with the conventional current measurement devices such as a shunt resistor with an ammeter or the multiple shunts consisting of molybdenum having a low temperature coefficient and a Rogowski coil with an integrated circuit. The currents in several electrical circuits have been measured using the developed current-voltage transferring device (CVTD) as voltages between the aluminum and copper elements. The measured voltages (V<inf>m</inf>) are proportional to measuring currents (I<inf>m</inf>), which is shown as the following the experimental equation V<inf>m</inf> [mV] =kI<inf>m</inf> [A], in which k is a coefficient depending on the configuration of the CVTD.
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Polymorphic microsatellite markers in the long-spined sea urchin Diadema setosum
(2014-12-01)
Wang, Mingling
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Li, Zhe
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Ganmanee, Monthon
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Xie, James Y.
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Urriago, Juan Diego
We developed twenty polymorphic microsatellite markers for the long-spined sea urchin Diadema setosum by screening microsatellite enriched library, and characterized their polymorphism using two populations of 45 individuals. The number of alleles per locus ranged from 4 to 17, and the observed and expected heterozygosity varied from 0.0714 to 1.000 and 0.6655 to 0.9321, respectively. Twelve loci conformed to the Hardy–Weinberg equilibrium after Bonferroni correction. These polymorphic microsatellite markers will facilitate studies of population genetics and connectivity in D. setosum.
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Influence of thermal aging on microhardness and microstructure of Sn-0.3Ag-0.7Cu-xIn lead-free solders
(2010-08-31)
Kanlayasiri, Kannachai
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Ariga, Tadashi
Sn-0.3Ag-0.7Cu is a low-silver lead-free solder, and provides a thinner brittle Ag<inf>3</inf>Sn intermetallic layer during soldering process. In this paper, effects of thermal aging on microhardness, and microstructure of Sn-0.3Ag-0.7Cu-xIn lead-free solders were investigated. Indium was added to lower the melting temperature, and varied from 0.0 to 3.0 wt%. The solders were thermally aged at 100 °C for 1, 10, 100, and 1000 h. Results showed that microhardness of the solders decreases as the aging time increases, and average grain size of the microstructure is larger with the increase of the aging time. It was also found that the higher In content in the solder provides the greater decreasing rate of its microhardness. © 2010 Elsevier B.V. All rights reserved.
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A white LED driver using a buck-boost converter
(2010-01-01)
Eguchi, Kei
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Pongswatd, Sawai
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Watanabe, Toshiya
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Pannil, Pittaya
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Tirasesth, Kitti
For mobile backlighting applications, a white LED (WLED) driver using a buck-boost converter is proposed in this letter. Unlike conventional converters using boost converters, 2×/1.5× charge pumps, and so on, the proposed converter offers the negative stepped-down voltage to drive the LED's cathode only when the input voltage is insufficient to drive a 1× transfer mode. Furthermore, unlike the LED backlight using charge pumps, the proposed converter can adjust the output voltage by controlling the duty factor of the clock pulse. Thus, the proposed converter can realize high power efficiency. The validity of the proposed converter is confirmed by simulations and experiments. © 2010 Institute of Electrical Engineers of Japan.
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Accurate CMOS-based Current Conveyors
(1991-01-01)
Surakampontorn, Wanlop
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Riewruja, Vanchai
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Kumwachara, Kiattisak
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Dejhan, Kobchai
An integrable circuit technique for implementing both positive and negative second generation current conveyors (CCII) is described in this paper. The realization method is suitable for fabricating in CMOS technology. The performance of the CMOS-based CCIIs is discussed in detail. Simulation and experimental results are also included. © 1991 IEEE

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