• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.3
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• pp.573-581
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• 1994

A microstrip antenna having a dual polarization and a smaller size than feed horn polarizer of F.R.R.S(Faraday Rotation Rotary Switch) is designed, in which GaAs MESFET switches are inserted for selective reception of RHCP or LHCP. For an accurate analysis of the resonance frequency, input impedance and radiation pattern of the circularly polarized microstrip antenna, finite difference time domain (FDTD) method is used. When the GaAs MESFET switch in the feeder is ON-stats, the truncated patch antenna has a gain of about 16.6dB including amplifier gain, while the switch is OFF-state, this has a isolation level of -24dB.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.5
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• pp.10-16
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• 2000

This paper presents new double-sided 3-dB branch-line coupler using CPW-to-Microstrip via-hole transitions for the multi-layer applications. The characteristic impedance is obtained using the even-odd mode method, and the circuit performance Is accurately estimated by the Finite Difference Time Domain(FDTD) method. The fabricated double-sided 3-dB branch-line coupler has less than 0.3 dB power dividing imbalance and 1。 phase imbalance, greater than 30 dB isolation, and 25 dB return loss over a 20% bandwidth centered at 2 GHz. Calculated and fabricated results show that this coupler provides better performance as compared to the conventional microstrip branch-line couplers.

• CELLMED
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• v.8 no.4
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• pp.22.1-22.5
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• 2018

Most modern adults are overweight or obese. Health services are troubling to overcome the large number of individuals in need of weight loss. Music therapy is emerging as a new option. Among various music therapy methods, it studied various treatments through Korean traditional music, and it is thought that Korean traditional music is a good therapy for diet. The present review focused on find the most useful condition for weight control by using Korean traditional music. National Center for Korean Traditional Performing Arts measured the dB of Korean traditional music, In the next, listen to other dB's music while eating and compared energy intake, water intake, duration of meals, number of servings, number of bites, eating rate (bites per minute), and bite size (grams). As a result of the exhibits, differences in food intake were also found in the difference of dB. 60 dB of music showed a decrease in energy intake. It suggests that Korean traditional music belonging to 60 dB brings weight loss effect. As a result, the effect of weight loss is shown by use Korean traditional music. However, future studies should be performed to reduce the energy intake by increasing the exposure period to Korean traditional music

• Journal of Audiology & Otology
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• v.23 no.4
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• pp.181-186
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• 2019

Background and Objectives: This study compared the perception of mono-syllabic and bisyllabic words in Tamil by young normal hearing adults in the presence of multi-talker speech babble at two signal-to-noise ratios (SNRs). Further for this comparison, a speech perception in noise test was constructed using existing mono-syllabic and bi-syllabic word lists in Tamil. Subjects and Methods: A total of 30 participants with normal hearing in the age range of 18 to 25 years participated in the study. Speech-in-noise test in Tamil (SPIN-T) constructed using mono-syllabic and bi-syllabic words in Tamil was used as stimuli. The stimuli were presented in the background of multi-talker speech babble at two SNRs (0 dB and +10 dB SNR). Results: The effect of noise on SPIN-T varied with SNR. All the participants performed better at +10 dB SNR, the higher of the two SNRs considered. Additionally, at +10 dB SNR performance did not vary significantly for neither mono-syllabic or bi-syllabic words. However, a significant difference existed at 0 dB SNR. Conclusions: The current study indicated that higher SNR leads to better performance. In addition, bi-syllabic words were identified with minimal errors compared to mono-syllabic words. Spectral cues were the most affected in the presence of noise leading to more of place of articulation errors for both mono-syllabic and bi-syllabic words.

• Korean Journal of Audiology
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• v.23 no.4
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• pp.181-186
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• 2019

Background and Objectives: This study compared the perception of mono-syllabic and bisyllabic words in Tamil by young normal hearing adults in the presence of multi-talker speech babble at two signal-to-noise ratios (SNRs). Further for this comparison, a speech perception in noise test was constructed using existing mono-syllabic and bi-syllabic word lists in Tamil. Subjects and Methods: A total of 30 participants with normal hearing in the age range of 18 to 25 years participated in the study. Speech-in-noise test in Tamil (SPIN-T) constructed using mono-syllabic and bi-syllabic words in Tamil was used as stimuli. The stimuli were presented in the background of multi-talker speech babble at two SNRs (0 dB and +10 dB SNR). Results: The effect of noise on SPIN-T varied with SNR. All the participants performed better at +10 dB SNR, the higher of the two SNRs considered. Additionally, at +10 dB SNR performance did not vary significantly for neither mono-syllabic or bi-syllabic words. However, a significant difference existed at 0 dB SNR. Conclusions: The current study indicated that higher SNR leads to better performance. In addition, bi-syllabic words were identified with minimal errors compared to mono-syllabic words. Spectral cues were the most affected in the presence of noise leading to more of place of articulation errors for both mono-syllabic and bi-syllabic words.

• Journal of the Korean Applied Science and Technology
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• v.7 no.2
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• pp.1-10
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• 1990

This study was attempted to report the effect of Does for Job's tear on steroid hormone changes in rats. Experimental object was one male rat and four female rats in one group. The experimental diet keeped pace with basal diet and Does of Job's tear. A group was basal diet and basal diet & Does for Job's tea was B group(1/day), C group(2/day). D group(3/day), F group(1 day among 3 day, 3/day), G group (1day among 5 day. 3/day) and E group was made diet & Job's tear(3/day). The reduce of weight was appeared to higher in D group and revealed to higher was F, C, B, G and A group. The changes of steroid hormone were showed to significant difference in A group and indicated to significant difference were G, F, B, C, D and E group.

• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.4
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• pp.415-423
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• 2009

To investigate low frequency acoustic transmissions in the Sub-Polar Front(SPF) of the East Sea, numerical experiments are conducted with Range dependent Acoustic Model(RAM) using Circulation Research of the East Asian Marginal Seas(CREAMS) data and Autonomous Profiling Explorer(APEX)) data. Significant seasonal variations of sea water properties are existed across the Sub-Polar Front(SPF) region from the north and the south. The model results show that Transmission Loss(TL) decrease(about 20dB) with ideal front in the warm region whereas TL increase(about 25dB) with ideal front in the cold region. Regardless of season(both in summer and winter), when the sound source is located in the cold region of the SPF, the model results show weak TL, compared to the case of the source in the warm region(Maximum difference of TL reaches 28dB). This difference between the cases when the source is located in the cold region and the warm region, is accounted for from the different vertical profiles of sound speed in both regions.

• Journal of Hydrogen and New Energy
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• v.21 no.3
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• pp.149-157
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• 2010

The electromagnetic characteristics of FCEVs (fuel cell electric vehicles) are much different from the existing combustion engine cars as well as hybrid, plug-in-hybrid, and pure electric vehicles due to the high voltage/current generated by a fuel cell stack which uses a compressed hydrogen gas reacted with oxygen. To operate fuel cell stack efficiently, BOP (Balance of Plant) is essential. BOP systems are used many not only for motors in water pump, air blower, and hydrogen recycling pump but also inverters for these motors. Since these systems or components are connected by high voltage cables, EMC (Electromagnetic compatibility) analysis for high voltage/current cable is the most important element to prevent the possible electric functional safety errors. In this paper, electromagnetic fields of high current/voltage cable for FCEVs is studied. From numerical analysis results, time harmonic magnetic field strength of high current/voltage cable have difference of 20～28 dB according to phase. EMI result considered ground effect of FECV at 10 m shows difference of 14.5 dB at 30 MHz and 2.8 dB at 230 MHz compared with general cable.

• Journal of Acupuncture Research
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• v.19 no.5
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• pp.124-135
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• 2002

Objective : This study was done to observe the effects on the thermal changes of herbal acupuncture. There were remarkable local thermal changes between pre and post herbal acupuncture therapy on D.I.T.I. or not. If there are those, we examine how long changes of those were maintained, what is the adequate interval on herbal acupuncture therapy. Methods : D.I.T.I, was used to study the local thermal changes in herbal acupuncture therapy. Determination of this analysis periods are pre and post-therapy(1hour, 1day, 7days later). The study group was divided into six groups that are NS group(No.=20), CF group(No.=22), BU group(No.=23), BUM group(No.=19), HP group(No.=20) and BV group(No.=l9). The herbal acupuncture was injected by 0.2ml divided into 0.05ml at the Fengmen(風門: B12), Feishu(肺兪: B13), Fufen(附分: B41), Pohu(魄戶: B42) 4 points. Then, we checked the thermal changes of their point after performing. Results : The following results were obtained ; 1. In CF groups, significant dermatothermal difference between pre and post therapy was not checked, In BU group that continued until post-therapy 1day, in HP group until 1hour, in BV group until 2days. In BUM, HP and BV group, Most dermatothermal difference was checked at post-therapy 1hour, in BU group at post-therapy 1day. 2. At post-therapy 1 hour, significant dermatothermal different between pre and post therapy was checked among BU group, BUM group, HP group and BV group. At post-therapy 1day and 2days, checked among BU group, BUM group and BV group. At post-therapy 7days, not checked among all groups. The group that highest dermatothermal difference were checked is BV group.

• Korean journal of food and cookery science
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• v.27 no.1
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• pp.55-62
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• 2011

The aim of this study was to investigate the effects of UV-B irradiation on the physicochemical characteristics of oyster mushrooms (Pleurotus ostreatus). Vitamin $D_2$ concentration, weight loss rate, color value, total plate counts and consumer acceptability of irradiated oyster mushrooms were measured. UV-B irradiation at doses of $0\;kj/m^2$, $20\;kj/m^2$ and $40\;kj/m^2$, significantly increased the vitamin $D_2$ concentrations from $0\;{\mu}g/g$ dry weight (control) to $85.87\;{\mu}g/g$ dw and $116.28\;{\mu}g/g$ dw, respectively, at 5% level. Rate of weight loss was also significantly increased from 0% (control) to 2.21% and 4.31% at $20\;kj/m^2$ and $40\;kj/m^2$ UV-B irradiation, respectively, at 5% level. Although there was no significant difference between the UV-B irradiated groups, total plate counts were significantly decreased from $1.0{\times}10^5$ (control) to $9.4{\times}10^3$ and $1.9{\times}10^3$at $20\;kj/m^2$ and $40\;kj/m^2$ of UV-B irradiation, respectively, at 5% level. There was no significant difference in L values and consumer acceptability between the groups. Therefore, UV-B irradiated oyster mushrooms could be used as health promoting ingredients for many foods.