• Journal of the Society of Cosmetic Scientists of Korea
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• v.37 no.1
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• pp.43-53
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• 2011

The conditions in fluid-bed processor for nanoencapsulation of azelaic acid-milk nano powder for acne nanocosmetics were optimized by response surface methodology (RSM). The maximum value of yield was 70.97 %. The yield was appreciably influenced by inlet air temperature, atomizing pressure, and feeding speed. The particle size increased with an increase in the feeding speed and a decrease in the atomizing pressure. The elution rate in saline solutions was appreciably influenced by inlet air temperature and atomizing pressure. The moisture content increased with higher atomizing pressure, which was demonstrated to be similar to the nanoencapsulation characteristics related to water activity. The Hunter's L and b values increased with an increase in the inlet air temperature. The optimum conditions estimated by RSM for the maximized values of yield, moisture content, particle size and elution rate in skin suitability were $67{\sim}73^{\circ}C$ of inlet air temperature, 0.6 ~ 0.8 mL/min feeding speed and 1.8 ~ 2.0 kg/$cm^2$ of atomizing pressure, respectively. These estimated values were in agreement with those measured by real experiments.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.37 no.1
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• pp.1-21
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• 2011

This review describes several kinds of emulsification methods for nanoemulsions and the application of nanoemulsions. Nanoemulsion droplet sizes fall typically in the range of 20 ~200 nm and show narrow size distributions. Although most of the publications on either oil-in-water (O/W) or water-in-oil (W/O) nanoemulsions have reported their formation by dispersion or high-energy emulsification methods, an increased interest is observed in the study of nano-emulsion formation by condensation or low-energy emulsification methods based on the phase transitions that take place during the emulsification process. Phase behaviour studies have shown that the size of the droplets is governed by the surfactant phase structure (bicontinuous microemulsion or lamellar) at the inversion point induced by either temperature or composition. Studies on nanoemulsion formation by the phase inversion temperature (PIT) method have shown a relation between minimum droplet size and complete solubilization of the oil in a microemulsion bicontinuous phase independently of whether the initial phase equilibrium is single or multiphase. Due to their small droplet size nanoemulsions possess stability against sedimentation or creaming with Ostwald ripening forming the main mechanism of nanoemulsion breakdown. An application of nanoemulsions is the preparation of nanoparticles using a polymerizable monomer as the disperse phase where nanoemulsion droplets act as nanoreactors, cosmetics and controlled drug delivery. In this review, we mainly focus on the cosmetics.

• Journal of Fisheries and Marine Sciences Education
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• v.9 no.2
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• pp.149-166
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• 1997

This thesis is studied by means of operation diary of the factory ship GAECHEOG in the Sea of Okhotsk and the Sea of Bering from Jul. 1993 to Dec. 1996, We summarize these results as follows : 1. The factory ship GAECHEOG equipped trawl winch able to haul raw fish 700M/T per day and cargo winch able to unload manufactured goods 900M/T. The crews consist of 290~330 persons. 2. Factory machineries equipped surimi making plant able to process about 150M/T per day and fish meal plant able to manufacture about 70M/T per day. 3. The fishing ground from June to Nov. was the western Bering sea lying in the eastern Kamchaka peninsula and from Dec. to May, the fishing period to gather roe of a Pollack, was the Sea of Ohotsk lying in the western Kamchaka peninsula. 4. The buying catch of fish per each voyage from Dec. to May, the fishing period gathering Pollack-roe, was about 17,000~33,000M/T and from Jul. to Oct., the fishing period gathering non Pollack-roe, was about 10,000~21,000 M/T. 5. Raw fish was the most about 33,000M/T of the 2nd voyage in 1994 and was the least about 8,300M/T of the 1st voyage in 1993. Other voyages were about 13,000~18,000M/T. 6. The Pollack buying from Jul. to Nov. in the Bering sea was 5~7 fishes for one row in pan and body length about 40~50cm, and from Dec. to May in the Sea of Ohotsk was 6~8 fishes for one row in pan and body length about 37~45cm. 7. Surimi production in the 2nd voyage in 1994 was the most about 7,300 M/T, in the 1st voyage in 1993 was the least 1,900M/T and in other voyages was about 2,500~3,800M/T. The extraction rate of surimi goods for raw fish was about 17.4~26.5%. 8. Fish meal production in the 2nd voyage in 1994 was the most about 2,300 M/T, in the 1st voyage in 1993 was the least about 780M/T and in other voyages was about 1,100~1,700M/T. The extraction rate of fish meal goods for raw fish was about 7.3~10.7%. 9. Pollack-roe production was very much from Jan. to Apr. and was about 380~700M/T per each voyage. The extraction rate of Pollack-roe for raw fish was about 1.2~4.9%.

• Journal of the Korean Geophysical Society
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• v.5 no.2
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• pp.143-151
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• 2002

Bulku temple in the city of Kyungju, Korea, built in 791 and reconstructed in the 20th century, is the home of seven national treasures including two three-story stone pagodas, Dabotap (height 10.4m, width 7.4m, weight 123.2ton) and Seokgatap (height 10.8m, width 4.4m, weight 82.3 ton). An earlier archaeological investigation shows that stone pagodas have experienced severe weathering process which will threaten their stability. At the base part of Dabotap, an offset of the stone alignment is also observed. For the purpose of the structural safety diagnosis of two pagodas, we introduce the nondestructive geophysical methods. Site characteristics around the pagodas are determined by the measurement of multiple properties such as seismic velocity, resistivity, image of GPR(ground-penetrating radar). Near the pagodas, the occurrence of high resistivity (up to 2200 Ωm) is obvious whereas their outskirts have as low as 200 Ωm. For the velocity of the P wave, the site of Dabotap has the range of 500~800 m/s which is higher than counterpart of Seokgatap with the velocity of 300~500m/s, indicating the solider stability of Dabotap site. Consequently, in addition to GPR images, the foundation boundaries beneath each stone pagodas are revealed. The Dabotap site is in the form of an octagon having 6-m-long side with the depth of ~4m, whereas the Seokgatap site the 9m × 10m rectangle with the depth of 3m. These subsurface structures appear to reflect the original foundations constructed against the stone load of ~8 ton/㎡. At the subsurface beneath the northeast of each pagoda, low seismic velocity as well as low resistivity is prominent. It is interpreted to represent the weak underground condition.

• Journal of the Korean Geophysical Society
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• v.8 no.3
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• pp.109-113
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• 2005

The ground-motion (GM) attenuation relations available in Korea has required the validation process for large earthquakes since most of them were developed based on small earthquake database. The Fukuoka earthquake (M=7.0) that occurred near the Korean Peninsula provides invaluable data to indirectly evaluate the attenuation characteristics of the strong GM in Korea. The GM levels (PGA, SA) obtained from the KIK-net downhole stations near the epicenter (R<100km) are reasonably predicted by the GM attenuation relation developed by KEPRI in 2003 for the Kori NPP site, the result of which validates the use of KEPRI GM attenuation relation for predicting GM induced by future large earthquakes. Also, the comparison between the Osaki spectra and response spectra of KIK-net downhole data reveals that the amplitude levels of Osaki spectra are higher than the spectra from KIK-net stations which are believed to be installed at the seismic basement.

• Geophysics and Geophysical Exploration
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• v.7 no.2
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• pp.109-116
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• 2004

Petroleum reservoir characterization is a process for quantitatively describing various reservoir properties in spatial variability using all the available field data. Porosity and permeability are the two fundamental reservoir properties which relate to the amount of fluid contained in a reservoir and its ability to flow. These properties have a significant impact on petroleum fields operations and reservoir management. In un-cored intervals and well of heterogeneous formation, porosity and permeability estimation from conventional well logs has a difficult and complex problem to solve by conventional statistical methods. This paper suggests an intelligent technique using fuzzy logic and neural network to determine reservoir properties from well logs. Fuzzy curve analysis based on fuzzy logics is used for selecting the best related well logs with core porosity and permeability data. Neural network is used as a nonlinear regression method to develop transformation between the selected well logs and core analysis data. The intelligent technique is demonstrated with an application to the well data in offshore Korea. The results show that this technique can make more accurate and reliable properties estimation compared with previously used methods. The intelligent technique can be utilized a powerful tool for reservoir characterization from well logs in oil and natural gas development projects.

• Geophysics and Geophysical Exploration
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• v.19 no.1
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• pp.11-19
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• 2016

Two representative residual static methods of traveltime decomposition and stack-power maximization are discussed in terms of application to land seismic data. For the model data with synthetic shot/receiver statics (time shift) applied and random noises added, continuities of reflection event are much improved by stack-power maximization method, resulting the derived time-shifts approximately equal to the synthetic statics. Optimal parameters (maximum allowable shift, correlation window, iteration number) for residual statics are effectively chosen with diagnostic displays of CSP (common shot point) stack and CRP (common receiver point) stack as well as CMP gather. In addition to removal of long-wavelength time shift by refraction statics, prior to residual statics, processing steps of f-k filter, predictive deconvolution and time variant spectral whitening are employed to attenuate noises and thereby to minimize the error during the correlation process. The reflectors including horizontal layer of reservoir are more clearly shown in the variable-density section through repicking the velocities after residual statics and inverse NMO correction.

• Journal of Software Engineering Society
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• v.27 no.1
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• pp.8-14
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• 2018

As cloud computing has emerged as a hot trend in the IT industry, various types of cloud services have emerged. In addition, cloud service broker (CSB) technology has emerged to alleviate the complexity of the process of selecting the desired service that user wants among the various cloud services. One of the key features of the CSB is to recommend the best cloud services to users. In general, CSB can use a method to evaluate a service by receiving feedback about a service from users in order to recommend a cloud service. However, since each user has different criteria for giving a rating, there is a problem that reliability of service evaluation can be low when the rating is only used. In this paper, a method is proposed to supplement evaluation of rating based service by applying machine learning based sentiment analysis to cloud service user's review. In addition, the CSB prototype is implemented based on proposed method. Further, the results of comparing the performance of various learning algorithms is proposed that can be used for sentiment analysis through experiments using actual cloud service review as learning data. The proposed service evaluation method complements the disadvantages of the existing rating-based service evaluation and can reflect the service quality in terms of user experience.

• Sijohaknonchong
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• v.22
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• pp.57-83
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• 2005

This article reviewed ‘Gojangsijoseonju(고장시조선주)' which was written by Gojeong-ok(.고정옥), a scholar of Korean literature. and showed the features and importance in the history of Korean literature. Gojeong-ok was not properly studied in the history of Korean literature for the time being because he went to North Korea during the Korean war. Even for the researcher on Korean literature.' the literary works of Gojeong-ok were not introduced properly. However, the systematic studies on Gojeong-ok and his literary works should be done, and should be well appreciate his work in the history of the research for Korean literature by his achievements. This article considered his literary achievement through his book, 'Gojangsijoseonju'. 'Jangsijo(장시조), that was named by Gojeong-ok for 'Saseolsijo(사설시조), stood in highly important position to explain the history of literarature in late period of Chosun(조선) Dynasty. He tried the analysis on the fifty (50) selected 'Saseolsijo' and made commentaries on them in his book. And he suggested the original and creative theory on 'Saseolsijo' at the time of the book published. This article considered his understandings on the poems of classical literature, revealed in his literary works, and especially, the features on the theory for the 'Jangsijo'. Through this process, it could be clearly understand his views on literary works in itself. By considering the analysis of literature that was introduced with the commentaries, it could be seen the aspects of the specific analysis on each literature. Through these works, it could be looked forward to getting more detailed investigating clue on the view of Gojeong-ok for the poems of classical literature.

• Journal of the Korea Society for Simulation
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• v.16 no.2
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• pp.27-35
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• 2007

When sensor networks are deployed in open environments, all the sensor nodes are vulnerable to physical threat. An attacker can physically capture a sensor node and obtain the security information including the keys used for data authentication. An attacker can easily inject false reports into the sensor network through the compromised node. False report can lead to not only false alarms but also the depletion of limited energy resource in battery powered sensor networks. To overcome this threat, Fan Ye et al. proposed that statistical on-route filtering scheme(SEF) can do verify the false report during the forwarding process. In this scheme, the choice of a security threshold value is important since it trades off detection power and energy, where security threshold value is the number of message authentication code for verification of false report. In this paper, we propose a fuzzy rule-based system for security threshold determination that can conserve energy, while it provides sufficient detection power in the SEF based sensor networks. The fuzzy logic determines a security threshold by considering the probability of a node having non-compromised keys, the number of compromised partitions, and the remaining energy of nodes. The fuzzy based threshold value can conserve energy, while it provides sufficient detection power.