• Journal of Aquaculture
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• v.8 no.4
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• pp.271-283
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• 1995

Blue tilapia, Oreochromis aureus (Steindachner) swim-up fry were fed a ration containing 0, 1, 10, or 60 ppm $17\alpha-Methyltestosterone$ (MT) for 30 days (sex reversal period). Fish that had been fed 0 ppm MT-treated feed during the sex reversal period were subsequently fed rations containing either 0 ppm MT, 10 ppm MT, or 60 ppm MT for the next 39 days (post sex reversal period) : fish that had been fed 60 ppm MT-treated feed during the sex reversal period were subsequently fed rations containing either 0 ppm MT, 10 ppm MT, or 60 ppm MT during the post sex reversal period. One group was fed 1 ppm MT-treated feed, while another group was fed 10 ppm MT-treated feed during both periods. The following growing season (10 months later), the residual effects of MT on weight gain, body composition, and gonosomatic indices (GSI) were evaluated. MT had no residual effect on growth of either sex. Groups that ate MT-treated feed were significantly (P<0.05) larger than those that received no MT during the sex reversal period, because females in the latter group lowered average weight gain. MT had a positive residual effect on body fat content in males, but had a negative effect on body moisture content. MT had a positive residual effect on body moisture content in females. MT had a significant negative effect on male and female GSI at the end of the post sex reversal period. MT consumption during the sex reversal period had a significant negative residual effect on male GSI. MT fed after sexual development (post sex reversal period) did not have a residual effect on male or female CSI.

• Journal of the Korean Magnetics Society
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• v.6 no.4
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• pp.199-203
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• 1996

To study the magnetization reversal behavior of Co/Pd multilayers, we first demagnetized the samples by the field-demagnetized method and then measured initial curves and minor loops. The coercivity and the perpendicular magnetic anisotropy were obtained from the perpendicular and parallel magnetization curves measured at different temperatures. We interpret our experimental results by applying several qualitative and semiquantative approaches. From these study, we found that the magnetization reversal behavior is dominated by the domain wall pinning for all samples and the coercivity incremental tendency can be explained by Kronmuller's formula $H_c(T)\;{\propto}\;r_0.K_u$.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.95-100
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• 2020

Nifty Bank Index has started trading in futures and options (F&O) segment from 13^th June 2005 in National Stock Exchange. The purpose of the study is to enhance the literature by examining expiration effect on the price volatility and price reversal of Underlying Index in India. Historical data used for the current study primarily comprise of daily close prices of Nifty Bank which is the only equity sectoral index in India which is traded in derivatives market and its Future contract value is derived from the underlying CNX Bank Index during the period 1^st January 2010 till 31^st March 2020. To check stationarity of the data, Augmented Dicky Fuller test was used. The study employed ARMA- EGARCH model for analysing the data. The empirical results revealed that there is no effect on the mean returns of underlying Index and EGARCH (1,1) model furthermore shows there is existence of leverage effect in the Bank Index i.e., negative shocks causes more fluctuations in the Index than positive news of similar magnitude. The outcome of the study specifies that there is no effect on volatility on the underlying sectoral index due to expiration days and also observed no price reversal effect once the expiration days are over.

• The Journal of the Acoustical Society of Korea
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• v.29 no.5
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• pp.295-302
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• 2010

This paper proposes a multiple access method based on Time Reversal Mirror (TRM) technique when the multiple sensor nodes exist. Proposed method increases system sum capacity using energy focusing effects of the TRM. Simulation results show that proposed algorithm obtains higher system sum capacity than Orthogonal Frequency Division Multiple Access (OFDMA), e.g., 27 bps/Hz higher than the OFDMA method when the number of sensor node is 30, the number of transducer is 8, and is SINR 16 dB.

• Journal of Distribution Science
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• v.22 no.9
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• pp.49-63
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• 2024

Purpose: This study examines how psychological heuristics influence stock price dynamics in Korea's distribution industry after significant price shocks. Research Design, Data, and Methodology: The study analyzes daily stock price movements exceeding 10% for Korean distribution companies from 1993 to 2022. It establishes anchoring heuristic reference points, including the 52-week high and low, and segments the sample based on company size and volatility. Results: We analyzed a sample previously studied by Lee et al. (2023). Our findings indicate that when a stock experiences a positive (negative) price shock near its 52-week high (or lowest price), investors in large (small) companies exhibit an optimism (pessimism) bias. This leads to overreactions and subsequent stock price reversals after the event date. Conversely, when a stock encounters a negative (positive) price shock near its 52-week high (or lowest price), investorstend to underreact due to anchoring heuristics. Thisresultsin a drift effect on the stock price after the event day. Notably, investor behavior around 52-week highs or lows directly impacts their heuristic behavior related to those price points. Conclusions: This paper uniquely examines behavioral biases among distribution-related stock investors in Korea, shedding light on stock price reversal and drift effects.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1206-1212
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• 2018

In this study, the polarization reversal characteristics of thin film capacitors with a thickness of 100 nm or less fabricated with ferroelectric polymer were measured and analyzed. For the fixed film thickness, polarization reversal occurred at higher coercive fields as the applied maximum electric field increased. For the fixed maximum electric field, polarization reversal occurred at the same coercive field irrespective of the thickness of the thin film. The proportional constant values between the logarithmic electric field and the logarithmic scale frequency were $0.12{\pm}0.01$ for all measurements. As a result, the ferroelectric polymer capacitors consistently exhibited polarization reversal characteristics without any size effects up to a thickness of 40 nm. This study shows the possibility of a polymer memory device that can operate at low voltage, which is useful for predicting the behavior of a low-voltage operating polymer memory device.

• PNF and Movement
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• v.13 no.3
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• pp.119-125
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• 2015

Purpose: The current study seeks to examine the effects of stabilizing reversal(SR) and rhythmic stabilization(RS) in proprioceptive neuromuscular facilitation (PNF) techniques on static balance in normal female adults. Methods: Subjects included 20 healthy women in their 20s. They were randomly divided into SR and RS groups. To assess static balance before and after PNF intervention, the good balance system was used to measure the interior and exterior center of pressure (COP) movement distance, front and rear COP movement distance before and after the intervention, and velocity moment. Results: Interior and exterior COP movement distance, front and rear COP movement distance, and velocity moment decreased in the SR group, but no statistically significant differences were observed. In the RS group, the interior and exterior COP movement distance declined without any significant difference, while the front and rear COP movement distance and velocity moment significantly decreased. The interior and exterior COP movement distance, front and rear COP movement distance, and velocity moment declined more in the RS group than in the SR group. Conclusion: The findings of the current study indicate that the RS technique is more effective than the SR technique for improving the balance ability of healthy female adults. The results of this study can thus be utilized in the selection of effective interventions for improving the balance ability of healthy female adults.

• PNF and Movement
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• v.16 no.3
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• pp.333-343
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• 2018

Purpose: The purpose of this study was to investigate the effects of a neck exercise using a proprioceptive neuromuscular facilitation (PNF) neck flexion and extension pattern on body balance in a progressive range of positions (supine, prone on elbow, and sitting), on numbness in the upper extremities, and on neck flexion motions in cervical myelopathy patients. Methods: One participant who was diagnosed with cervical myelopathy participated in this study. A reversal design (A-B-A') was used. The A and A' were the baseline period (no intervention), and B was the intervention period. The intervention used a neck extension pattern with a hold-relax technique and a neck flexion pattern with a combination of isotonic techniques in the supine position. Then, neck flexion and extension patterns were applied together with a reversal technique for stabilization, followed by a neck extension pattern with a combination of isotonic techniques in the prone position on the elbows. Finally, a neck flexion and extension pattern was used with a stabilizing reversal technique, and a neck extension pattern was applied with a combination of isotonic techniques in the sitting position for 60 minutes per day, 3 times per week for 8 weeks. To measure balance, numbness, and neck motion during neck flexion, the one-leg stand test and the visual analogue scale were used. Results: The right and left one-leg stand tests showed increased balance ability in the intervention phase. Upper extremity numbness was decreased in the intervention phase, and neck flexion motion was increased in the intervention phase. These increases were maintained after the intervention (Baseline II). Conclusion: These results suggest that a neck exercise using a PNF neck pattern with additional techniques in a progressive range of positions has a positive effect on cervical myelopathy patients for balance, numbness, and neck motion.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.5
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• pp.573-579
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• 2004

Electroflotation, which is used as an alternative to sedimentation, is a separation treatment process that uses small bubbles to remove low-density particulates. Making allowances for recent collision efficiency diagram based on trajectory analysis, it is necessary to tailor zeta potential of bubbles that collide with negatively charged particles. In this paper, the study was performed to investigate the effects of magnesium and aluminium ions on zeta potential of bubbles. And, it was studied to find out factors which could affect the positively charged bubbles. Consequently, zeta potential of bubbles increased both with higher concentration of metal ions and in the acidic pH value. And, a probable principle that explained the procedure of charge reversal could be a combined mechanism with both specific adsorption of hydroxylated species and laying down of hydroxide precipitate. It also depended on the metal ion concentration in the solution to display its capacity to control the bubble surface.

• The Journal of Internal Korean Medicine
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• v.41 no.5
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• pp.806-810
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• 2020

Objectives: The aim of this study was to investigate the effects of Korean medicine treatment on a patient suffering from nausea, vomiting, and headache. Methods: We applied herbal medicine (Oryeong-san, Wiryeong-tang) and acupuncture to the patient. Clinical symptoms were assessed with a numeral rating scale (NRS). Results: After treatment, the nausea, vomiting and headache symptoms were improved, and the NRS score showed improvement. Conclusion: This case shows that Korean medicine treatments are effective in alleviating the symptoms of nausea, vomiting, and headache.