• Korean Journal of Clinical Pharmacy
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• v.14 no.2
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• pp.78-84
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• 2004

Nifedipine, one of calcium channel antagonists, has been used for the treatment of mild to moderate hypertention, angina pectoris, Raynaud's phenomenon and various other cardiovascular diseases. Because of its short biological half-life, several sustained-release (SR) formulations of nifedipine have been developed. and used clinically. The bioequivalence of the two nifedipine SR preparations was evaluated according to the guidelines of KFDA. The test product was Hanmi Nifedipine SR $tablet^{(R)}$ made by Hanmi Pharm. Co. and the reference was Adalat Oros $tablet^{(R)}$ made by Bayer Korea. Thirty healthy male subjects were divided into two groups and a randomized $2\times2$ cross-over study was employed. After one SR tablet containing 33 mg of nifedipine was orally administered, blood sample was taken at predetermined time intervals and the concentrations of nifedipine in plasma were determined using a validated HPLC method with UV detector. Two pharmacokinetic parameters, $AUC_t\;and\;C_{max}$, were calculated and analyzed statistically for the evaluation of bioequivalence of the two products. Analysis of variance was carried out using logarithmically transformed parameter values. The $90\%$ confidence intewals of the $AUC_t\;and\;the\;C_{max}\;were\;log\;0.81\sim1og\;1.19\;and\;log\;0.84\sim\;log\;1.13,\;respectively.$ These values were within the acceptable bioequivalence intervals from log 0.8 to log 1.25 in KFDA guidelines. Thus, the criteria of the KFDA guidelines for the bioequivalence was satisfied, indicating that Hanmi Nifedipine SR tablet is bioequivalent to Adalat Oros tablet.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.6
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• pp.587-595
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• 1999

This study was designed to investigate effects of calcium antagonists on endothelial and neuronal dysfunction of right coronary artery (RCA) induced by ischemia- reperfusion in anesthetized, open-chest pigs. After reperfusion, pigs were sacrificed and the RCA was rapidly dissected for in vitro experiments. Experimental groups were divided into 4 groups: control (C-RCA), ischemia-reperfusion only (I-RCA), verapamil infusion (VI-RCA) and nifedipine infusion (NI-RCA) group, respectively. The ischemia did not affect hemodynamics, mean arterial pressure, heart rate, LVdP/dtmax, and decreased RCA flow. Arterial pressure and heart rate during ischemia-reperfusion were decreased in VI-RCA and NI-RCA, and RCA flow during reperfusion was increased in NI-RCA. 5-Hydroxytryptamine (5-HT) produced concentration-dependent contractions in C-RCA. The 5-HT-induced contractions were potentiated in I-RCA and VI-RCA, but not in NI-RCA. Endothelium-dependent relaxation by calcium ionophore A23187 was inhibited in I-RCA and VI-RCA, and recovered in NI-RCA. Cyclic GMP contents were decreased in I-RCA group alone. Electrical field stimulation in C-RCA produced transient and frequency-dependent contractions and at 50 Hz caused biphasic contractions. The transient contractions were not affected by pretreatment with phentolamine and atropine, but the biphasic contraction was altered by the pretreatment. Both contractions were inhibited in I-RCA, and were partially recovered in VI-RCA and NI-RCA. Ischemia-reperfusion of RCA in pigs causes endothelial and neuronal dysfunctions, and calcium antagonists partially prevent both.

• Journal of Fashion Business
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• v.20 no.1
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• pp.1-16
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• 2016

Korean cosmetic distribution channels were formerly divided into sales visits and specialty shops, which made up the entire cosmetics market. However, recently the market and cosmetic distribution channels have become much more diversified. Thus, research for this study focused on the usage and purchase situations of cosmetic distribution channels depending on cosmetic type perception. This study also focused on the intent to purchase cosmetics by a cosmetic distribution channel in order to provide a precise cognitive background of consumers regarding cosmetic distribution channels. In doing so, the competitiveness of those channels could be procured and the causal relationships between these variables can be investigated. To achieve these purposes, the research model and hypotheses were derived through literature research on the cosmetics industry, cosmetic distribution channels, and consumers' intent to purchase. A survey was implemented from September $1^{st}$ to $14^{th}$, 2014 for empirical testing. and was given to female consumers in their 20s. 468 out of 500 surveys were collected; a total of 415 were used for analysis while the others were excluded due to with unreliable responses. The SPSS 21.0 program was used for analysis of materials. The overall conclusion of this study is that there is a relationship between perception of cosmetic distribution channels and intent to purchase. The above research results may stimulate establishment of marketing implications and research material when establishing marketing strategies to promote cosmetic distribution and consumption.

• Reproductive and Developmental Biology
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• v.33 no.1
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• pp.55-61
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• 2009

The epididymis in the male reproductive tract is the site where spermatozoa produced from the testis become mature. The epididymis is divided into 4 different segments, initial segment and caput, corpus, and caudal epididymis, depending upon functional and morphological features. Aquaporins (Aqps) are water channel molecules, which are present in the epididymis and play a major role in removal of epididymal water, resulting in creation of microenvironment for sperm maturation and concentration of sperms. Nandrolone decanoate (ND) is a synthetic anabolic-androgenic steroid, which is used to treat clinical diseases and improve physical ability and appearance. Even though it is well determined that the ND causes the male infertility by affecting the testis, little is known the effect of the ND on the epididymis. The present study was focused to examine the effect of ND at different treatment doses and periods on expression of Aqp1 and Aqp9 genes in the epididymis of pubertal rats. Results showed that mRNA expression of Aqp1 and Aqp9 genes among the parts of the epididymis was differentially regulated by ND treatment doses. In addition, treatment periods of ND caused differential expression of Aqp1 and Aqp9 mRNAs among segments of the epididymis. Therefore, it is believed that male infertility induced by ND could be resulted not only from malfunction of the testis but also from aberrant gene expression of Aqp1 and Aqp9 in the epididymis.

• Ocean and Polar Research
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• v.30 no.3
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• pp.261-275
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• 2008

The profile of a fixed site at station M ($34.77^{\circ}N,\;129.13^{\circ}E$) in the Korea Strait was studied from March 2006 to February 2007. The aim was to understand the relationship between the annual thermal stratification pattern and seasonal variation in phytoplankton community structure. Physicochemical factors including temperature, salinity and nutrient concentrations, which strongly influence the proliferation and diversity of phytoplankton, were measured. The study period was divided into three due to the characteristic of thermohaline structures; mixed I (March-May 2006), stratified (June-November 2006) and mixed II(December 2006-Feburuary 2007). Diatoms dominated during the mixed I (89%) and II (48%) periods, while nanoplankton group occupied over 83% of total population during the stratified period. The dominant species during the mixed I and II was Chaetoceros socialis (47% and 29%, respectively), while during the stratified period Gyrodinium sp.(4%) was the most dominant. Averaged total chl a concentrations during the mixed I and II periods were 0.61 mg $m^{-3}$ and 0.72 mg $m^{-3}$, respectively, which were at least two-fold higher than that during the stratified period (0.30 mg $m^{-3}$). The vertical mixing and convection process of the water column induced nutrient supply from the bottom layer to the euphotic zone. It also led to the dominance of diatoms during the mixed periods, whereas small phytoplankton prevailed over large phytoplankton as stratification blocked the upward movement of nutrients to subsurface during the stratified period. During the mixed I and II periods, microplanktonic chl a dominated concentrations (50% and 48%, respectively), while picoplanktonic chl a occupied over 37% of total chl a during the stratified period.

• Journal of Advanced Navigation Technology
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• v.10 no.1
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• pp.41-47
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• 2006

In this paper, a predistortion linearizer using the in-phase modulator is proposed. The harmonic generator of the proposed predistorter extracts a second harmonic signals. These signals are divided in-phase and quadrature-phase signals, and then amplifying each signals using variable gain amplifier. An in-phase modulator, modulate fundamental signal with second harmonic signals, generates the predistortion intermodulation distortion (IM) signals and controls amplitude and phase of them with modulation factors. As a result, this predistorter is suppressed intermodulation distortion signals of power amplifier effectively. The proposed linearizer has been implemented to operate in Cellular-band. The test results show that the third order IM is cancelled more than 20dB in case of CW 2-tone signals with ${\Delta}f$=1MHz. Also, it's improved the adjacent channel power ratio (ACPR) more than 7dB for IS-95 CDMA 1FA signals.

• Journal of the Korean Institute of Oriental Medical Informatics
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• v.15 no.2
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• pp.77-91
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• 2009

Flowery Knotweed Root is the dried tuberous root of the knotweed family wheres Auriculate Swallowwort Root is the dried tuberous root of the swallowort family. Flowery Knotweed Root is also called Red Flowery Knotweed Root in China, which is dried root of Polygonum multiflorum THUMB. Chinese Flowery Knotweed Root is better known as the dried tuberous root belonging to the family Apocynaceae whereas White Flowery Knotweed Root in Korea is the dried tuberous root of Cynanchum wilfordii(Maxim) Hemsl. Up to now, while the dried root named Red Flowery Knotweed Root has been widely used in China, Auriculate Swallowwort Root has been widely used in Korea. Both the roots contrast in a striking way with the origin, shape, botanical names, other names, and chemical constituents, so administration and dosage without discrimination of both sides can be open to question. According to the literature, it is recorded that Flowery Knotweed Root and Auriculate Swallowwort Root are similar to the characteristics, properties, and actions. From this study, the result is as follows: 1. Flowery Knotweed Root and Auriculate Swallowwort Root are divided into the family Apocynaceae and the family Polygonaceae, respectively. Accordingly 2. Flowery Knotweed Root is in shape of an irregular spindle and looks reddish- brown or deep reddish-brown and the section is light yellowish-brown, while Auriculate Swallowwort Root looks yellowish-brown and the section is white or yellow. 3. Flowery Knotweed Root is reported by the Journal of the Crude Drug that the medicinals have not the same therapeutic action as Auriculate Swallowwort Root. It is recorded that the properties, channel entry, functions of Flowery Knotweed Root and Auriculate Swallowwort Root in literature have much in common. Many works on the roots of this plant has been used traditionally as a tonic are required of. In view of the results, Flowery Knotweed Root and Auriculate Swallowwort Root varies both in nature and in shape, so that the administration and dosage of the medicinals must be taken a prudent attitude.

• Journal of the Korean earth science society
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• v.33 no.1
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• pp.1-10
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• 2012

Analysis on high-resolution seismic and core data reveals that the sedimentary strata in Gyeonggi Bay consists of four sedimentary units (Unit I-IV, from top to bottom) formed during the late Quaternary period. Unit I is interpreted as sediments of tidal flat and channel-fill deposits, formed during the Holocene transgression. Unit II is divided into shallow-marine facies unit in offshore area and channelized fluvial to estuarine facies unit in nearshore sand ridge and tidal flat. Unit III is considered as tidal flat deposits with the uppermost severely weathered and oxydized layers. This unit is composed of shallow marine sedimentary successions formed during the MIS-5 highstand. The lowermost Unit IV rests on Mesozoic basement rocks, considered as the shallow marine and shelf deposits formed before the MIS-5 lowstand.

• Journal of the Korean GEO-environmental Society
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• v.18 no.1
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• pp.13-21
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• 2017

In this study, the behavior characteristics and triggering rainfall of debris flow were investigated on the basis of DB constructed by performing field investigation and collecting the rainfall data at the sites where debris flow occurred around the west of Gangwon and adjacent areas during the last 10 years. For hill slope and channelized type of debris flow, its behavior characteristic was analyzed through runout channel of debris flow divided into zone of initiation, transportation and deposition and its magnitude was estimated by considering erosion at zones of initiation and transportation. Some considerations related to establishment of landslide forecasting criterion were raised by comparing the analyzed results of analysis of rainfall at the time of debris-flow occurrence with the previous researches about the triggering rainfall of debris flow. In addition, an ID curve of inducing debris flow adequate to the investigated site was proposed and compared with results of previous study.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.178-182
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• 2000

During the past five years, there has born tremendous interest worldwide in the possibility of exploiting chaos in wideband communication systems. Many different demodulation techniques have been proposed up to date. They can be divided into two basic categories. In the first approach, like the conventional coherent demodulation techniques, the chaotic signal has to be recovered from the received noisy signal by synchronization. However, the chaotic synchronization techniques published to data are so sensitive to the channel noise and distortion that these techniques can not be used in radio communications. In the second approach, the demodulation is carried out nonsynchronization. This paper surveys the different chaotic communication techniques that can be implemented nonsynchronization and compares the threshold and BER of the different methods. Finally, FM-DCSK is introduced the first step for apply to wideband chaos digital CDMA, where the data is not limited by the inherent nonperiodic property of the chaotic signal.