• Journal of the Society of Cosmetic Scientists of Korea
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• v.28 no.1
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• pp.99-115
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• 2002

Tests of stability and toxicity, and clinical evaluation of anti-acne activity suggest that cryptotanshinone, a constituent of the roots of Salvia miltiorrhiza Bunge, is an effective active ingredient for acne vulgaris treatments. Acne vulgaris, called acne or pimples, is the most common disease of the pilosebaceous follicle unit of the skin. It affects nearly 80% of people between the ages of 11 and 30. Approximately 30% of teenagers have acne of sufficient severity to require medical treatment. Acne is a follicular disorder of the skin. It occurs in specialized pilosebaceous units on the face and body. Acne develops when these specialized follicles undergo pathologic alterations that result in the formation of non-inflammatory lesions (comedones) and inflammatory lesions (papules, pustules and nodules). An abnormality of keratinizing epithelium of these follicles, thought to be due to the action of sebum synthesized and secreted by the androgen-sensitive sebaceous glands, leads to inflammation induced by the follicular bacterium Propionibacterium acnes. Therapy involves treatments that modify these pathogenic factors and includes drugs with antikeratinizing, antibacterial and antiseborrheic actions. Acne vulgaris is a very frequent disease, seen primarily in adolescents, involving the sebaceous follicles. Acne vulgaris is characterized by a great variety of clinical inflammatory and non-inflammatory lesions: comedones, papules, pustules, nodules, cysts and scars. Acne vulgaris is a multi-factorial disease. Although its pathogenicity is unclear, extensive studies have shown that hyperseborrhea, superinfection by P. acnes and endocrinologic androgenic changes play a role in the development of acne vulgaris.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.1
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• pp.123-145
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• 2017

Due to the increasing demand for spectrum resources, cognitive radio networks and dynamic spectrum access draw a lot of research into efficiently utilizing limited spectrum resources. To set up cluster-based CR ad-hoc common channels, conventional methods require a relatively long time to successfully exchange the initialization messages. In this paper, we propose a fast and reliable common channel initialization protocol for CR ad-hoc networks. In the proposed method, the cluster head sequentially broadcasts a system activation signal through its available channels with a predetermined correlation pattern. To detect the cluster head's broadcasting channels and to join the cluster, each member node implements fast Fourier transform (FFT) and computes autocorrelation of an FFT bin sequence for each available channel of the member node. This is compared to the predetermined reference pattern. The join request and channel decision procedures are also presented in this paper. In a simulation study, the performance of the proposed method is evaluated.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.513-522
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• 1997

Annual variations In main fishing grounds of common squid with different angling and their fishing conditions in Korean waters were studied by analyzing catch and water temperature data. The main fishing grounds of squid angling fishery started to moved to the north in April and to the south in September in the last Sea of Korea. The catch of squid was related to the direction of thermal fronts. The catch was high when the thermal front was formed in the east-west direction, while there was low catch when the thermal front was formed in the south-north direction which runs parallel to the roast.

• Journal of Bio-Environment Control
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• v.8 no.2
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• pp.90-98
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• 1999

This study was conducted to select proper substrate and nutrient solution concentration for favorable growth and quality in common thyme (Thymus vulgaris L.). The growth of common thyme was better in deep flow culture (DFT) than in other substrate cultures. As the nutrient solution concentration rose, the ratio of dry matter increased, while the fresh weight and the number of lateral shoots decreased. The contents of total chlorophyll and vitamin C were higher in DFT than others. Ca, K, P were showed high contents in cocopeat, but Mg content was the highest at half-fold concentration in DFT. Common thyme showed low content of nitrate in DFT compared with that in other substrate culture. DFT was the most effective system for pronoting growth and quality of common thyme. The optimal concentration of nutrient solution in common thyme was half-fold(EC=1.2mS/cm) of herbs nutrient solution by European Vegetable R&D Center.

• Journal of applied mathematics & informatics
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• v.22 no.1_2
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• pp.411-424
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• 2006

The purpose of this paper, using the idea of intuitionistic fuzzy set due to Atanassov [2], we define the notion of intuitionistic fuzzy metric spaces (see, [1]) due to Kramosil and Michalek [17] and Jungck's common fixed point theorem ([11]) is generalized to intuitionistic fuzzy metric spaces. Further, we first formulate the definition of weakly commuting and R-weakly commuting mappings in intuitionistic fuzzy metric spaces and prove the intuitionistic fuzzy version of Pant's theorem ([21]).

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.4
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• pp.89-95
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• 2013

In this work, the evaluation of swirl nozzle injector performance was conducted by investigating effective area ($A_{eff}$), injection mass ($m_{inj}$), injection rate ($Q_{inj}$), and injection delay ($t_{delay}$) under various test conditions. To achieve these, fuel injection analysis system which was composed of fuel supply system, injection system, and control system was installed. At the same time, the swirl nozzle that had 12 orifice hole with $120^{\circ}$ injection angle was used in this work. It was revealed that the difference of injection mass ($m_{inj}$) between base and swirl nozzle injector increased as the injection pressure ($P_{inj}$) and energizing duration ($t_{eng}$) decreased under the same test conditions. The maximum injection rate ($Q_{inj}$) of swirl nozzle injector was higher than base nozzle injector about 2~5%. The injection performance of swirl nozzle was better than base nozzle at low injection pressure ($P_{inj}$) and short energizing duration ($t_{eng}$) conditions.

• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.3
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• pp.10-21
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• 2022

The propellant tank, which is a space launch vehicle structure, must have structural integrity as various static and dynamic loads are applied during ground transportation, launch standby, take-off and flight processes. Because of these characteristics, the propellant tank cylinder, the structural object of this study, has a thin thickness, so buckling due to compressive load is considered important in the cylinder design. However, the existing buckling design standards such as NASA and Europe are fairly conservative and do not reflect the latest design and manufacturing technologies. In this study, nonlinear buckling analysis is performed using various analysis models that reflect initial defects, and a method for establishing new buckling design standards for cylinder structures is presented. In conclusion, it was confirmed that an effective lightweight design of the cylinder structure for common bulkhead propulsion tank could be realized.

• Journal of Pharmaceutical Investigation
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• v.25 no.3
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• pp.193-204
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• 1995

In order to examine the effect of extrahepatic cholestasis induced by common bile duct ligation on the hepatic function, the pharmacokinetics of antipyrine and d-propranolol were investigated in rats. In addition, in an attempt to observe the degree of direct hepatic injury, light and electron microscopic observations and conventional pathologic test using serum were performed. Five days after common bile duct ligation, antipyrine(15 mg/kg) and d-propranolol(3 mg/kg) were intravenously administrated to the rats, respectively. The total clearances of antipyrine and d-propranolol were significantly(p<0.05) decreased. Because hepatic clearance of antipyrine poorly extracted by the liver and that of d-propranolol highly extracted by the liver are respectively dependent on the hepatic intrinsic clearance and the hepatic blood flow, it may be concluded that extrahepatic cholestasis following five days after common bile duct ligation decreased the hepatic intrinsic clearance and the hepatic blood flow. SGPT, SGOT, cholesterol, bilirubin(total bilirubin, direct bilirubin) and alkaline phosphatase were significantly increased(p<0.05). The proliferation of bile ducts was prominent, and degeneration and necrosis of hepatocytes were observed by light microscope. Also, ultrastructurally, bile canaliculi were containing the amorphous materials and losing microvilli, and SER and RER in hepatocytes were dilated and vacuolated.

• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.3
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• pp.32-42
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• 2022

The strategy to develop a launch vehicle family by bundling multiple rocket engines of a single type has been proven by SpaceX and their reusable fleet comprised of Falcon 9 and Falcon Heavy. In this study, we revisit a potential launch vehicle family out of a 35 tonf-class methalox staged combustion cycle engine and evaluate their utility and performance in various space missions. For example, a Korean version of Falcon 9 can deliver 4.7 tons of payload into 500 km SSO in an expendable mode while the payload is reduced to 2.16 tons in a sea-landing reusable mode. A Korean version of Falcon Heavy can deliver 4.4 tons into GTO when launched from the Naro Space Center, indicating that this common booster core configuration can handle Cheollian 2 albeit the high inclination. Once developed, the same methaloax engine can power the first-stage of smallsat launch vehicles and air launch vehicles.

• Korean Journal of Computational Design and Engineering
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• v.21 no.2
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• pp.186-195
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• 2016

The finite element modeling of a ship for hull structural analysis on the basis of new harmonized common structural rules (CSR-H) is to be extended to the cargo holds in fore and after body of a ship. Unlike the parallel middle-body where the external and internal features of hull are equal along to the longitudinal direction of a ship, in fore and after body, the external and internal features of hull vary linearly or even irregularly in forms of a surface or a curve along to the longitudinal direction of a ship. Thus, it needs lots of design man-hours for the modeling for structural analysis. In order to save man-hours in initial structural design phase of a ship, the specified 3D CAD system has been adopted in shipbuilding industry. Through the interface between CAD and CAE (rule scantling and direct strength assessment), design man-hour in initial design phase can be saved even under the environment of CSR-H.