• Culinary science and hospitality research
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• v.3
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• pp.271-289
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• 1997

The purpose of this study is to investigate previous data and possibility of the new culture building, insuring substantiality of the education in junior college, increasing of practical carrier, acquiring the money for practical class, and the direction of demand for education in a high level of industrial society. There's two parts to consist of investigation and the model case in wedding business in Junior college. The research groups in one part consist of 277 students in Junior college. The result were as follows: 1) The students would like to get the wedding business in new culture building. (72%) 2) The student shave got a idea to recommend to use the wedding facilities for their for their relative sand friends. (51%) 3) The trend of selecting in wedding facilities is outside than inside of facilities. (75%) 4) They would like to have the buffet service after wedding celemony, not a la carte for choose the meal. The above research data suggest that if the wedding facility's management would be accept, we could have expectation about development of junior college, emphasis of practical education and good wedding culture in this areas. For the most of student, they has a righ hand to manage the wedding facility in their college. First, the culinary students could have an experience of service practies to the customer in wedding celemony, as the result of training will be great. Second, the college could show their vision and hope to customer to interest it. Third, it can be supplied the right wedding culture and the wedding facilities which is low price and good circumstance for wedding. Fourth, it's very resonable to use the culture facilities during no class, Saturday and Sunday. Fifth, income from business can be used only a scholarship and a community development. Sixth, it can be induced the self-participication and motivation to take up a positive attitude for their life.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.119-119
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• 1997

Valacyclovir is a L-valyl ester prodrug of acyclovir which is a highly effective and selective antiviral agent in the treatment of herpes virus diseases. Valacyclovir is rapidly and almost completely converted to acyclovir and increases the oral bioavailability of acyclovir three to five fold. However, the intestinal absorption mechanism of valacyclovir is not clear. If the improved absorption mechanism of valacyclovir is fully understood, it will provide a rationale of designing the amino acid ester prodrugs of polar drugs containing hydroxyl group. The main objective of our present study is to characterize the membrane transport mechanism of valacyclovir. Methods : Intestinal absorption of valacyclovir was investigated by using in-situ rat perfusion study and its wall permeability was estimated by modified boundary layer model. The membrane transport mechanism was also investigated through the uptake study in Caco-2 cells and in CHO-hPepTl cells. Results : In the rat perfusion study, the wall permeability of valacyclovir was ten times higher than acyclovir and showed concentration dependency, Valacyclovir also demonstrated a D,L stereo-selectivity with L-isomer having an approximately five-fold higher permeability than D-isomer. Mixed dipeptides and cephalexin, which are transported by dipeptide carriers, strongly competed with valacyclovir for the intestinal absorption, while L-valine did not show any competition with valacyclovir. This indicated that the intestinal absorption of valacyclovir could be dipeptide carrier-mediated. In addition, the competitive uptake study in Caco-2 cells presented that dipeptides reduced the valacyclovir uptake but valine did not. Also, in IC$\sub$50/ study, valacyclovir showed strong inhibition on the $^3$H-gly-sar uptake in CHO-hPepTl cells over-expressing a human intestinal peptide transporter. Taken together, the result from our present study indicated that valacyclovir utilized the peptide transporter for the intestinal absorption.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.57-57
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• 2011

지진해일은 진행속도가 빠르고 파장이 길며 파형의 변화 없이 먼 거리를 진행 할 수 있어 주변지역은 물론 멀리 떨어진 지역에도 심한 범람피해를 야기시킨다. 지진해일의 일반적인 특징으로 장파와 단파가 합성되어 있고 먼 거리를 전파할 경우 분산효과의 역할이 중요하게 된다. 특히 우리나라의 동해안에 영향을 주는 지진해일은 단주기파 성분이 강하고 파장에 비해 먼 거리를 전파하기에 분산을 고려하는 선형 Boussinesq 방정식을 지배방정식으로 사용하는 것이 바람직하다. 하지만 지금까지의 지진해일 전파모의를 위한 모형은 선형 Boussinesq 방정식의 복잡한 계산과 계산시간이 길다는 단점 때문에 선형 천수방정식을 지배방정식으로 사용하고 분산효과는 수치분산을 이용하여 고려해왔다. 지진해일 해석 시 일반적으로 사용되어 오던 기존의 leap-frog 유한차분 모형(Imamura et al., 1988; 조용식, 1996)은 지배방정식으로 선형 천수방정식을 사용하고 파의 분산효과는 수치분산을 이용하여 고려하므로 정해진 시간 간격에 대해 수심에 따라 격자 간격을 적절히 선택해야 하는데 수심이 복잡하게 변하는 경우 격자간격 조정이 불가능하여 분산효과를 정도 높게 고려할 수 없다. 이 문제점을 해결하기 위하여 윤성범 등(2004)은 파동방정식의 인위적인 분산항을 이용하여 Boussinesq 방정식의 분산효과를 고려할 수 있는 능동적인 분산보정기법을 제안하였고 Cho et al.(2007)는 일정한 수심에서 수치적인 분산오차가 Boussinesq 방정식의 물리적인 분산항을 대체하도록 수심, 격자 간격 및 계산 시간 간격 사이의 관계식을 유도하고 Boussinesq 방정식의 분산항과 일치하는 수치분산을 이용하여 실용적인 분산보정기법을 개발하였다. 이에 Ahn(2010)은 현재 컴퓨터의 계산 능력이 향상되어 선형 Boussinesq 방정식을 직접 차분하여 계산하는데 무리가 없다고 판단하여 선형 Boussinesq 방정식을 직접 차분한 모형을 개발하였다. 본 연구에서는 기존의 원해 지진해일 전파모의에 이용되어왔던 선형 천수방정식에 수치분산을 고려한 모형 대신 선형 Boussinesq 방정식의 유한차분 모형을 제안하였으며 기존의 선형 Boussinesq 방정식 모형의 격자와 수심간의 제약을 없애기 위해 차분 기법을 달리 한 2차 정확도의 유한차분 모형을 제안하였다. 검증을 위하여 선형 Boussinesq 방정식의 해석해(Carrier, 1991)와 비교하였다.

• Journal of Pharmaceutical Investigation
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• v.35 no.1
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• pp.33-38
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• 2005

Recently increasing attention has been focused on solid lipid nanoparticles (SLN) as a parenteral drug carrier due to its numerous advantages that can come from both polymeric particle and fat emulsions, together with the possibility of controlled release and increasing drug stability. Lipophilic drugs such as paclitaxel, cyclosporin A, and all-trans retinoic acid have been successfully entrapped in SLN but the incorporation of hydrophilic drugs in SLN is very limited because of their very low affinity to the lipid. Therefore, as a new approach to improve the loading of hydrophilic drugs, a w/o/w emulsion technique has been developed. The primary objective of the current study was to improve the loading efficiency of a model hydrophilic drug, glycine (Log P = -3.44) into SLN. The proposed preparation process is as follows: A heated aqueous phase consisting of 0.1 ml of glycine solution in water (100 mg/ml), and poloxamer 188 (5 mg) were then added to a molten oil phase containing precirol (100 mg) and lecithin (5 mg). This mixture was dispersed by sonicator, leading to a w/o emulsion. A double emulsion (w/o/w) was formed after the addition of 2% poloxamer solution to the above dispersed system. After cooling the double emulsion, solid lipid nanosuspensions were successfully formed. The lipid nanoparticles had the mean particle size of 441.25 nm, and the average zeta potential of -20.98 mV. The drug loading efficiency was measured to be 8.54% and the drug loading amount was measured to be 0.92%. The w/o/w emulsion method showed an increased loading efficiency compared to conventional o/w emulsion method.

• Journal of Pharmaceutical Investigation
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• v.31 no.3
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• pp.185-190
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• 2001

Human papillomavirus (HPV) infection is known to cause cervical cancers. Human papillomavirus-like particles (VLP) have been studied as preventive vaccines of cervical cancers. To develop VLP as a therapeutic gene carrier, we studied the method to encapsulate cytokine genes in virus-like particles. HPV type 16 capsid L1 genes were amplified by polymerase chain reaction and cloned into T vector. L1 gene was then inserted into baculovirus transfer vector. The clone of baculovirus encoding L1 gene was isolated and used to express L1 protein in Sf 21 insect cells. VLP were purified by CsCl density gradient and ultracentrifugation. VLP were disassembled to capsomer units by treatment of a reducing agent. Given that interleukin-2 (IL-2) genes have been used in anticancer gene therapy and as a molecular adjuvant, IL-2 cytokine plasmids were chosen as a model gene. IL-2 plasmids were incubated with the disassembled capsomer suspension. To reassemble the particles, the mixture of capsomers and cytokine plasmids was dialyzed. The disassembly and reassembly of VLP were confirmed by transmission electron microscopy. The entrapment of cytokine plasmids in reassembled VLP was tested by the stability of plasmids against DNase I. After treatment of reassembled virus-like particles with DNase I, discrete IL-2 DNA band was observed. Our results indicate that IL-2 cytokine plasmid (3.5 kb size) can be encapsulated in the virus-like particles, suggesting the potential of VLP as a gene delivery system. Moreover, VLP containing the adjuvant cytokine plasmids might function as more effective subunit vaccines.

• Journal of Microbiology and Biotechnology
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• v.25 no.6
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• pp.803-813
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• 2015

The growth of Irpex lacteus F17 and manganese peroxidase (MnP) production in a selfdesigned tray bioreactor, operating in solid-state conditions at a laboratory scale, were studied. The bioreactor was divided into three layers by three perforated trays. Agroindustrial residues were used both as the carrier of bound mycelia and as a nutrient medium for the growth of I. lacteus F17. The maximum biomass production in the bioreactor was detected at 60 h of fermentation, which was consistent with the CO₂ releasing rate by the fungus. During the stationary phase of fungal growth, the maximum MnP activity was observed, reaching 950 U/l at 84 h. Scanning electron microscopy images clearly showed the growth situation of mycelia on the support matrix. Furthermore, the MnP produced by I. lacteus F17 in the bioreactor was isolated and purified, and the internal peptide sequences were also identified with mass spectrometry. The optimal activity of the enzyme was detected at pH 7 and 25℃, with a long half-life time of 9 days. In addition, the MnP exhibited significant stability within a broad pH range of 4-7 and at temperature up to 55℃. Besides this, the MnP showed the ability to decolorize the polymeric model dye Poly R-478 in vitro.

• Journal of Astronomy and Space Sciences
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• v.25 no.3
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• pp.283-290
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• 2008

Satellite formation flying can provide the platform for interferometric observation to acquire the precise data and ensure the flexibility for space mission. This paper presents development and verification of an algorithm to estimate the baseline between formation flying satellites. To estimate a baseline(relative navigation) in real time, EKF(Extended Kalman Filter) and UKF(Unscented Kalman Filter) are used. Measurements for updating a state-vector in Kalman Filter are GPS single difference data. In results, The position errors in estimated baseline are converged to less than ${\pm}1m$ in both EKF and UKF. And as using the two types of Kalman filter, it is clear that the unscented Kalman filter shows a relatively better performance than the extended Kalman filter by comparing an efficiency to the model which has a non-linearity.

• Journal of Navigation and Port Research
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• v.34 no.8
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• pp.649-657
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• 2010

In order to achieve a sustainable competitive advantage in the expanding maritime transportation market, most shipping companies are making every effort to reduce transportation costs. Likewise, the car shipping companies, which carry more than 80% of total car import and export logistics volume, also do their utmost for transportation cost saving. Until now many researches have been made for efficient maritime transportation, but studies for car shipping companies have rarely been made. For this reason, this study has tried to develop a maritime transportation planning support system which can help to save logistics costs and increase a competitive power of car shipping companies. To this end, instead of manual effort to solve the routing problem of car carrier vessels, this study has proposed a genetic algorithm. The performance of the genetic algorithm will be evaluated by comparing with the optimal solution of integer programming model.

• Journal of Communications and Networks
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• v.10 no.3
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• pp.287-296
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• 2008

The IEEE 802.11 wireless standard uses the carrier sense multiple access with collision avoidance (CSMA/CA) as its MAC protocol (during the distributed coordination function period). This protocol is an adaptation of the CSMA/CD of the wired networks. CSMA/CA mechanism cannot guarantee quality of service (QoS) required by the application because orits random access method. In this study, we propose a new MAC protocol that considers different types of traffic (e.g., voice and data) and for each traffic type different priority levels are assigned. To improve the QoS of IEEE 802.11 MAC protocols over a multi-channel CSMA/CA, we have developed a new admission policy for both voice and data traffics. This protocol can be performed in direct sequence spread spectrum (DSSS) or frequency hopping spread spectrum (FHSS). For voice traffic we reserve a channel, while for data traffic the access is random using a CSMA/CA mechanism, and in this case a selective reject and push-out mechanism is added to meet the quality of service required by data traffic. To study the performance of the proposed protocol and to show the benefits of our design, a mathematical model is built based on Markov chains. The system could be represented by a Markov chain which is difficult to solve as the state-space is too large. This is due to the resource management and user mobility. Thus, we propose to build an aggregated Markov chain with a smaller state-space that allows performance measures to be computed easily. We have used stochastic comparisons of Markov chains to prove that the proposed access protocol (with selective reject and push-out mechanisms) gives less loss rates of high priority connections (data and voices) than the traditional one (without admission policy and selective reject and push-out mechanisms). We give numerical results to confirm mathematical proofs.

• Journal of the Korean Magnetics Society
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• v.4 no.3
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• pp.272-276
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• 1994

A new Galvanomagnetic electrorootive force effect of $Ni_{53}-Fe_{47}$ thin films is studied. The dependence of this effect on $\theta$, angle between the current and the magnetic field, is found to be the form of sin $2\theta$, in contrast with that of the magneto resistance effect cas $2\theta$ and that of the Hall effect sin $\theta$. Property of this effect is that lthe rate of the voltage variation depending on the magnetic field is extremely large as compared with the magnetiresistance effect. It is theoretically confirmed that this effect is well understood on the basis of the two carrier types model.