• 한국정보시스템학회지:정보시스템연구
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• 제13권2호
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• pp.155-172
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• 2004

The purpose of this study is to investigate factors which can lead small buyers to participate in a Reverse Aggregation Electronic Market (RAEM). Five factors including search, selection, price, delivery, and Internet literacy were selected as possible factors which are expected to influence small buyers' participation in a RAEM. This paper focused on a RAEM of the Korean automotive industry in which the third party aggregator formed a group of small automobile repair shops (ARS) and amassed buying power for them by building a buyer' oriented electronic market (EM). Survey data were collected from small ARS in South Korea. The results of the empirical analysis indicated that fast delivery and support for Internet illiteracy are potential incentives that could influence buyers' decisions to join a RAEM.

• Journal of applied mathematics & informatics
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• 제19권1_2호
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• pp.215-229
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• 2005

In this paper, constraint aggregation is combined with the adjoint and multiple shooting strategies for optimal control of differential algebraic equations (DAE) systems. The approach retains the inherent parallelism of the conventional multiple shooting method, while also being much more efficient for large scale problems. Constraint aggregation is employed to reduce the number of nonlinear continuity constraints in each multiple shooting interval, and its derivatives are computed by the adjoint DAE solver DASPKADJOINT together with ADIFOR and TAMC, the automatic differentiation software for forward and reverse mode, respectively. Numerical experiments demonstrate the effectiveness of the approach.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2011년도 제44차 학술발표회
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• pp.67-67
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• 2011

Recently, Phthalocyanine dye has attentions due to their excellent photochemical properties and used to optical applications such as chemical sensors. And azo groups can change photochemical properties in the UV irradiation because their molecualr structure reverse cis-trans isomer and changes cooperative motion, aggregation and so on. In this study, we synthesized the azo compound between amino pyridine and phenol. this azo derivative used the combination with 3-nitro phthalonitrile and makes phthalocyanine structure through the synthesis with 1,8-diazabicyclo[5.4.0]undec-7-ene(DBU), zinc acetate. Finally, we synthesized a new photoswiching dye zinc-phthalocyanine azo compound. This compound was studied by phothoswichiing phenomenon by UV irradiation and analyzed molecular aggregation through the SEM images.

• Bulletin of the Korean Chemical Society
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• 제26권4호
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• pp.523-528
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• 2005

Diblock copolymers with different poly($\varepsilon$-caprolactone) (PCL) block lengths were synthesized by ringopening polymerization of $\varepsilon$-caprolactone in the presence of monomethoxy poly(ethylene glycol) (mPEG-OH, MW 2000) as initiator. The self-aggregation behaviors of the diblock copolymer nanoparticle, prepared by the diafiltration method, were investigated by using $^1H$ NMR, dynamic light scattering (DLS), and fluorescence spectroscopy. The PEG-PCL block copolymers formed the nano-sized self-aggregate in an aqueous environment by intrsa- and/or intermolecular association between hydrophobic PCL chains. The critical aggregation concentrations (cac) of the block copolymer self-aggregate became lower with increasing hydrophobic PCL block length. On the other hand, reverse trends of mean hydrodynamic diameters were measured by DLS owing to the increasing bulkiness of the hydrophobic chains and hydrophobic interaction between the PCL microdomains. The hydrodynamic diameters of the block copolymer nanoparticles, measured by DLS, were in the range of 65-270 nm. Furthermore, the size of the nanoparticles was scarcely affected by the concentration of the block copolymers in the range of 0.125-5 mg/mL owing to the negligible interparticular aggregation between the self-aggregated nanoparticles. Considered with the fairly low cac and nanoparticle stability, the PEG-PCL nanoparticles can be considered a potential candidate for biomedical applications such as drug carrier or imaging agent.

• 한국응용곤충학회지
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• 제41권4호
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• pp.233-238
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• 2002

경남 지역의 단감원에서 2000­2001년에 수은유아등과 2001년에 갈색날개노린재의 집합페로몬(methyl (E, E, Z)-2, 4, 6-decatrienoate)) 트랩을 이용하여 갈색날개노린재(Plautia stali)와 썩덩나무노린재(Halyomorpha halys)의 발생소장을 조사하였다. 유아등 조사결과 썩덩나무노린재는 6월 하순부터 발생하기 시작하여 8월 상ㆍ중순이 최성기이었다. 갈색날개노린재는 썩덩나무노린재와는 달리 유살 최성기가 뚜렷하지 않았는데, 主 유인시기는 2개년 모두 7월 중순­8월 하순이었다. 두 종 모두 9월 이후에는 거의 유살되지 않았다. 집합페로몬 트랩에 의한 유살 양상은 유아등에 의한 유살양상과 달랐다. 집합페로몬 트랩조사 결과, 두 종 모두 5월 중순부터 8월 하순까지 꾸준히 유인되었다. 썩덩나무노린재는 유인수가 적어 주 발생시기가 뚜렷하지 않았고, 갈색날개노린재는 지역에 따라 6월 하순부터 8월 하순 사이에 많이 유살되었다. 갈색날개노린재는 수은유아등 보다는 집합페로몬 트랩에, 썩덩나무노린재는 수은유아등에 더 많이 유인되었다. 또한 집합페로몬 트랩에는 두 종 모두 수컷보다 암컷이 더 많이 유인되었다. 두 종류의 트랩에 의한 유살소장 차이의 원인을 탄닌함량과 연관지어 고찰하였다.

• 한국응용과학기술학회지
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• 제27권4호
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• pp.391-398
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• 2010

Soybean lecithin liposomes composed phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl inositol and phosphatidic acid were prepared by using the previously developed supercritical reverse phase evaporation method. The effect of phospholipid composition on the formation of liposomes and physicochemical properties were examined by means of trapping efficiency measurements, transmission electron microscopy, dynamic light scattering and zeta potential measurements. The trapping efficiency of liposomes for D-(+)-glucose made of CNA-Ⅰ which contains approximately 95% phosphatidyl choline is higher than that of CNA-II and CNA-O which contain approximately 32% phosphatidyl choline. However there is no any difference between the trapping efficiency of liposomes for D-(+)-glucose made of CNA-II which has saturated hydrocarbons tails and that of liposomes made of CNA-O which has unsaturated hydrocarbon chains. The electron micrographs of liposomes made of CNA-II and CNA-O show small spherical liposomes with diameter of $0.1\sim0.25{\mu}m$, while that of CNA-I shows large unilamellar liposomes with diameter of $0.2\sim1.2{\mu}m$. These results clearly show that phospholipid structure of phosphatidylcholine allows an efficient preparation of large unilamellar liposomes and a high trapping efficiency for water soluble substances. Liposomes made of CNA-II and CNA-O remained well-dispersed for at least 14 days, while liposome suspension made of CNA-I separated in two phase at 14 days due to aggregation and fusion of liposomes. The dispersibility of liposomes made of CNA-I is lower than that of CNA-II and CNA-O due to the smallar zeta potential of CNA-I.

• 동의생리병리학회지
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• 제16권1호
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• pp.181-185
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• 2002

The thrombosis is the category of blood stasis. Blood stasis is a pathologicial state resulting from the reverse or impeded flow of blood in the body or the stagnation of blood flow in local parts as well as abnormal blood outside of the vessles which remains in the body and fails to disperse. Hwao-tang has been reported to have a hypolipidemic effect in patients with hypercholesterolemia, and in highcholesterol-induced experimental models. The present paper reports the effects of HOT on atherosclerosis using a spontaneous experimental model, Kurosawa and Kusanagi-hypercholesterolemic (KHC) rabbits. We have also investigated the pharmacological effect of extracts obtained from HOT on collagen-and ADP-induced blood platelet aggregation, thrombin-induced conversion of fibrinogen and fibrinolysis in in vitro experiments. In conclusion, the protection of extracts of Korean herbs' HOT on the ischemic infarction induced artificially might be involved to their inhibition of thrombotic action.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.237.2-237.2
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• 2003

DWP40458 is a novel human thrombopoietin mutein with two additional N-linked glycosylation site. The thermal stability of DWP40458 in both solution and lyophilized form was studied in the temperature range of 4-50$^{\circ}C$, compared with recombinant human TPO (rhTPO). When the aggregation or degradation pattern of DWP40458 and rhTPO solution was characterized by using SDS-PAGE, gel permeation chromatography (GPC) and reverse phase HPLC, it was found that thermostability of DWP40458 was significantly different to rhTPO in the temperature at 25, 40, 40, 50$^{\circ}C$. (omitted)

• 생명과학회지
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• 제17권4호
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• pp.575-580
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• 2007

여성의 폐경에 의한 estrogen의 감소는 심혈관계질환을 빠르게 진행시킨다고 알려져 있다. 최근 새로운 estrogen 대체 식물로 주목받고 있는 오디 추출물을 갱년기장애를 일으킨 흰쥐에 투여하여 혈액 유동성, 항 혈소판 응집능 및 혈 중 지질 수준 개선에 미치는 영향을 검토하였다. 오디 추출물 투여군의 경우 Ovx-control군보다 혈액 유동성이 빠르게 나타났고, 한국산 오디의 경우 sham군 정도의 혈액 유동성을 보였으며, 중국산의 경우는 sham군 보다 빠른 유동성을 나타내었다. 각 산지별 오디 추출물 투여군이 OVX-control군 보다 빠른 시간에 통과한 것으로 미루어 보아 오디가 혈액의 유동성에 좋은 영향을 줄 것으로 사료되어진다. 오디 추출물을 갱년기를 유도한 흰쥐에 투여하여 혈소판 응집 능에 미치는 영향을 검토한 결과 난소절제에 의하여 혈소판응집이 활성화 되었는데, 오디 추출물을 투여한 군에서 혈소판응집이 억제되는 것을 확인할 수 있었다. 또한, 난소 절제하여 갱년기 장애를 유도한 흰쥐에 각각의 오디 추출물을 투여하였을 때, total-cholesterol 및 혈 중 중성 지방이 낮아지고, HDL-cholesterol 함량이 높아지는 결과로 보아 국산 오디 추출물 뿐 아니라 타지키스탄, 중국산 오디 추출물 투여가 난소 절제에 의해 소실된 estrogen의 지질대사 불균형에 유익한 영향을 주어 관상동맥 질환 개선에 도움을 줄 것으로 사료된다.

• 한국농공학회지
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• 제31권2호
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• pp.43-53
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• 1989

In this research programs, a series test was conducted to show the effects of freeze/thaw process on the various soil properties. The tests were carried out taken from the west sea shore of Korean peninsular and the west sea shore of Scotland, and their results are as follows; 1. There was a positive total heave in a freezing run, although water may he expelled for the sample initially. The water flow must he reverse' from expulsion to intake. 2. The confining pressure had an overriding influence on the heave and frost penetration, a sudden change of the axial strain at failure with strain rate was observed occuring at a strain rate between 10-5 and 10-6, and the initial friction angle of frozen clay was appeared zero. 3. There was shown a significant decrease in liquid limit of soil which was subjected to freeze/thaw process for the initial value of about 20% because of soil particles aggregation. 4. The cyclic freeze/thaw caused a sinificant reduction in shear strength and its thixotropic regain. The frozen/thawed soil exibited negative strength regain, particularly at high freeze/thaw cycles. 5. The freezing temperature greatly influenced on the failure strength of soils and this. Trend was more pronounced the lower the freezing temperature and shown the ductile failure with indistinct peaks.