• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.4
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• pp.123-131
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• 2018

This study discusses that the US zoning system came from "progressive movement" in the early 20th century. The US progressive movement was closely related with the scientific management movement in terms of efficiency. In that context, the ontological significance of zoning is found in realizing public interests by blocking external effects based on the value-neutral expertise. Another aspect of the US zoning system is the political one. It is closely related to progressive movement in common with efficiency. The zoning system was introduced as a measure to prevent the racial and class mixture resulting from the influx of immigrants. Today, the racial aspect of zoning is succeeded to exclusionary zoning. This study examines the fact that exclusive interests of US mainstream society have served as more important background than the fundamental aspect preventing external effects in the introduction and evolution of the zoning system.

• Bulletin of the Korean Chemical Society
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• v.17 no.3
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• pp.239-244
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• 1996

Mastoparan B (MP-B) that is a novel MP isolated from the hornet Vespa basalis, was studied as compared with MP, in terms of interaction with phospholipid bilayer and antimicrobial activity. MP-B has more hydrophilic amino acid residues in hydrophilic face of amphiphilic α-helical structure than MP. The both peptides exhibited considerably different effect on interaction with lipid bilayers, e.g. their conformation in the presence of acidic and neutral liposomes, dye-release ability from encapsulated liposomes, but on the whole the interaction mode was similar. On antimicrobial activity, MP had a strong activity against Gram-positive bacteria but no against Gram negative ones. Contrary to this, MP-B had a strong activity against Gram-positive and potent against Gram-negative ones. Since both peptides have almost same residues on the hydrophobic side, such more hydrophilic surface on the molecule seems to lead to the subtle change in its interaction with membranes, resulting in the alternation in its biological activity.

• Membrane and Water Treatment
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• v.7 no.2
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• pp.101-113
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• 2016

In this study, to improve the water flux of porous hydrophobic membranes, various water-soluble polymers including neutral, cationic and anionic polymers were adsorbed using 'salting-out' method. The adsorbed hydrophobic membrane surfaces were characterized mainly via the measurements of contact angles and scanning electron microscopy (SEM) images. To enhance the durability of the modified membranes, the water-soluble polymers such poly(vinyl alcohol) (PVA) were crosslinked with glutaraldehyde (GA) and found to be resistant for more than 2 months in vigorously stirred water. The water flux was much more increased when the ionic polymers used as the coating materials rather than the neutral polymer and in this case, about 70% of $0.31L/m^2{\cdot}h$ (LMH) to 0.50 LMH was increased when 300 mg/L of polyacrylamide (PAAm) was used as the coating agents. Among the cationic coating polymers such as poly(styrene sulfonic acid-co-maleic acid) (PSSA_MA), poly(acrylic acid-comaleic acid) (PAM) and poly(acrylic acid) (PAA), PSSA_MA was found to be the best in terms of contact angle and water flux. In the case of PSSA_MA, the water flux was enhanced about 80%. The low concentration of the coating solution was better to hydrophilize while the high concentration inclined to block the pores on the membrane surfaces. The best coating condition was found: (1) coating concentration 150 to 300 mg/L, (2) ionic strength 0.15, (3) coating time 20 min.

• Journal of Mechanical Science and Technology
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• v.17 no.9
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• pp.1388-1396
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• 2003

The hydrodynamic instability of the three-dimensional boundary layer on a rotating disk introduces a periodic modulation of the mean flow in the form of stationary cross flow vortices. The instability labeled Type II by Faller occurs first at lower Reynolds number than that of well known Type I instability. Detailed numerical values of the amplification rates, neutral curves and other characteristics of the two instabilities have been calculated over a wide range of parameters. Presented are the neutral stability results concerning the two instability modes by solving the appropriate linear stability equations reformulated not only by considering whole convective terms but also by correcting some errors in the previous stability equations. The present stability results agree with the previously known ones within reasonable limit. Consequently, the flow is found to be always stable for a disturbance whose dimensionless wave number is greater than 0.75. Some spatial amplification contours have been computed for the stationary disturbance wave, whose azimuth angle $\varepsilon$= 11.29$^{\circ}$ to 15$^{\circ}$ and for the moving disturbance wave, whose azimuth angle $\varepsilon$ = 12.5$^{\circ}$ to 15$^{\circ}$. Also, some temporal amplification contours have been computed for the stationary disturbance wave, whose azimuth angle $\varepsilon$= 11.29$^{\circ}$ to 15$^{\circ}$ and for the moving disturbance wave, whose azimuth angle $\varepsilon$= 12$^{\circ}$ to 15$^{\circ}$. The flow instability was observed by using a white titanium tetrachloride gas over rotating disk system. When the numerical results are compared to the present experimental data, the numerical results agree quantitatively, indicating the existence of the selective frequency mechanism.

• Journal of Society of Preventive Korean Medicine
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• v.15 no.2
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• pp.131-143
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• 2011

Objective : The aims of this study are to investigate the trend of internet journalism about the toxicity and safety of the herbal medicine, and to suggest the regulatory solution of the issue. Method : In this study, we had searched the internet news article published from 2001 to 2011 in the five major portal sites-NAVER, DAUM, Nate, Google Korean, and Yahoo Korean. The search terms were 'herbal medicine', 'adverse event', 'toxicity'. If the articles described the same event in the same form and tone, the articles were considered overlapping. The overlapped articles were excluded. The articles were categorized by the form and tone. The form categories were straight news, interpretative story, editorial, interview, and the tone categories are the positive, the negative, and the neutral. The regulations were searched about the negative issue. Result : Total 56 articles were reviewed. There were 19 positive articles, 29 negative articles, 8 neutral articles. Most negative issues have the proper regulations, but insufficient measures for the adverse event reporting system. Conclusion : The herbal medicine specified adverse event reporting system is essential.

• Biomolecules & Therapeutics
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• v.18 no.1
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• pp.99-105
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• 2010

The purpose of this study was to evaluate relative bioavailability of the coenzyme Q10 (CoQ10) in emulsion and three liposome formulations after a single oral administration (60 mg/kg) into rats. Emulsion formulation of CoQ10 was prepared by conventional method using Phospholipon 85G as an emulsifier, and three liposome formulations (neutral, anionic, and cationic) of CoQ10 were prepared by traditional lipid film hydration technique using Phospholipon 85G, cholesterol, and charge carrier lipids (1,2-dioleoyl-3-trimethylammonium-propane chloride salt for cationic liposome and 1,2-dimyristoyl-sn-glycero-3-phosphate monosodium salt for anionic liposome). Mean particle size of all CoQ10-loaded liposome was less than a micron, and size distribution of the liposome population was homogeneous. Bioavailability of CoQ10 in emulsion was 1.5 to 2.6-fold greater than liposome formulations in terms of $AUC_{0-24\;h}$. $T_{max}$ was 3 h when administered as emulsion while it was greater than 6 h in liposome formulations. Notably, it was approximately 8 h in cationic liposome. $C_{max}$ was highest in emulsion and was significantly decreased when administered as liposome. Charged liposome showed even lower $C_{max}$ than neutral liposome, especially in cationic liposome. In conclusion, therefore, it is suggested that clinicians and patients consider bioavailability issue a primary concern when choosing a CoQ10 product, especially when very high plasma level is required such as in the treatment of heart failure and Parkinson's disease.

• The Korean Journal of Applied Statistics
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• v.29 no.1
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• pp.181-192
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• 2016

We consider several methods to approximate option prices with correction terms to the Black-Scholes option price. These methods are able to compute option prices from various risk-neutral distributions using relatively small data and simple computation. In this paper, we compare the performance of Edgeworth expansion, A-type and C-type Gram-Charlier expansions, a method of using Normal inverse gaussian distribution, and an asymptotic method of using nonlinear regression through simulation experiments and real KOSPI200 option data. We assume the variance gamma model in the simulation experiment, which has a closed-form solution for the option price among the pure jump $L{\acute{e}}vy$ processes. As a result, we found that methods to approximate an option price directly from the approximate price formula are better than methods to approximate option prices through the approximate risk-neutral density function. The method to approximate option prices by nonlinear regression showed relatively better performance among those compared.

• Journal of Electrical Engineering and Technology
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• v.7 no.1
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• pp.1-8
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• 2012

The current paper presents a novel control strategy of a three-phase, four-wire Unified Power Quality (UPQC) to improve power quality. The UPQC is realized by the integration of series and shunt active power filters (APF) sharing a common dc bus capacitor. The realization of shunt APF is carried out using a three-phase, four-leg Voltage Source Inverter (VSI), and the series APF is realized using a three-phase, three-leg VSI. To extract the fundamental source voltages as reference signals for series APF, a zero-crossing detector and sample-and-hold circuits are used. For the control of shunt APF, a simple scheme based on the real component of fundamental load current (I $Cos{\Phi}$) with reduced numbers of current sensors is applied. The performance of the applied control algorithm is evaluated in terms of power-factor correction, source neutral current mitigation, load balancing, and mitigation of voltage and current harmonics in a three-phase, four-wire distribution system for different combinations of linear and non-linear loads. The reference signals and sensed signals are used in a hysteresis controller to generate switching signals for shunt and series APFs. In this proposed UPQC control scheme, the current/voltage control is applied to the fundamental supply currents/voltages instead of fast-changing APF currents/voltages, thus reducing the computational delay and the required sensors. MATLAB/Simulink-based simulations that support the functionality of the UPQC are obtained.

• Speech Sciences
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• v.9 no.2
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• pp.69-87
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• 2002

This paper investigates how focus contributes to the phonological and phonetic realization of Japanese intonation. Pierrehumbert & Beckman (1988) pointed out that textual prominence results in the H-tone peak raising on the focused item and IP (Intonational Phrase) initiation before the focused item. Similarly Kori (1989) suggested that the F0 peaks on the words after the focused item tend to be suppressed. Although they give a general description of the characteristics of focus phenomena in Japanese intonation, they fail to explain the F0 peak interaction between H phrasal tone and lexically specified pitch accent in more-than-3-mora words whose accent locations varies from early to late. In this paper, we perform the experiment to investigate the following three points. First, we would like to look at the systematic intonational differences between focused and neutral APs; specifically, focused APs, either accented or unaccented, are compared with the neutral counterparts in terms of F0 pattern. Second, we investigate F0 patterns of a focused AP with more than 3 morae, as the accent of the word varies from early to late. Since an AP with a late accent has a H- on the second mora as well as H*+L on its accent mora, it is expected that these peaks will show systematic F0 pattern when it is focused. Our third concern is F0 patterns of a post focus AP with more than 3 morae, that is, whether a post-focus word is dephrased or just downstepped as the word accent location varies from early to late. This paper is significant in that it tries to clarify the F0 peak interaction between H-and lexical pitch accent H*+L in a variety of focus contexts in Japanese intonation.

• The Research Journal of the Costume Culture
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• v.16 no.2
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• pp.293-304
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• 2008

The objectives of this study were to investigate the images in men's hairstyle by hair color, tone, texture, and perceiver's gender, and to examine the characteristics of hairstyle appropriate to seasons. A quasi-experimental method by questionnaire was used, and the experimental design was $4{\times}3{\times}2{\times}2$(hair color$\times$tone$\times$texture$\times$perceiver's$\times$gender) factorial design. The subjects were 372 men and women in their 20s through 50s. five factors of men's hairstyle image were derived by factor analysis: individuality, dignity, romanticism, refinement, and activity. Black hair was perceived to be high in dignity and activity. Bright tone was perceived to be high in individuality, but low in dignity. Men's wave hair was perceived to be higher in individuality than straight hair, but lower in dignity. Perceiver's gender did not give significant influence on evaluation of all image factors. In brown, neutral tone was perceived to be higher in dignity. romanticism, and activity than dark or bright tone. In black, wave hair was perceived to be more refined than straight hair. Black hair matches with winter the most, and yellow matches with spring the most. In terms of tone, dark tone matches with winter; neutral tone matches with autumn; bright tone matches with summer. The results of this study verified that hair color and texture affect men's image perception, and matching hair colors are associated with seasons.