• Proceedings of the Materials Research Society of Korea Conference
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• 2010.05a
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• pp.43.1-43.1
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• 2010

조직공학의 중요한 요소로 작용하는 scaffold는 여러 가지 필수적인 조건들을 만족시켜야 한다. 대표적인 특징들로는 (1)생분해성 및 비독성, (2)넓은 표면적을 갖는 상호 연결된 내부 다공성 구조, (3)구조적 안정성, (4)세포부착 기질의 제공, (5)낮은 면역 반응성, (6)혈전 형성 억제, (7)친수성, (8)생체 기능성 등을 들 수 있다. 이러한 scaffold가 갖추어야 할 특성 중에서 세포 부착 기질 제공을 위하여 scaffold에 표면 개질을 통한 기능기를 도입하였다. 본 연구에서는 BCP scaffold의 구조적 안정성 부여를 위하여 PCL(polycaprolactone)을 infiltration 하였다. PCL은 소수성의 특징을 갖고 있어 세포와 상호작용 할 수 있는 생물학적 반응기가 없기 때문에 세포와의 친화성이 떨어진다. 세포의 친화성을 높여주기 위해 실리콘의 전구체인 TEOS(tetraethly orthosilicate)를 코팅하고, 그 위에 카복실기(carboxylic acid group)를 도입하였다. 또한 세포의 고정화를 높여주기 위해 fibronectin을 코팅하여 BCP/PCL scaffold의 세포 친화성을 높여주었다. 이와 같이 제조된 고기능성 BCP/PCL scaffold의 내부 구조와 특성을 Micro-CT로 확인하였고, 또한 실리콘 코팅 여부를 확인하기 위하여 SEM-EDS를 통해 관찰하였으며, FT-IR 관찰을 통해 카복실기 도입 여부를 확인 하였다. 또한 생체적합성 평가를 위해 MTT assay, 조골세포의 부착에 미치는 영향을 관찰하기 위해 SEM, 조골세포의 유전자 발현에 미치는 영향을 관찰하기 위해 RT-PCR을 통해 확인 하였다.

• The KIPS Transactions:PartD
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• v.9D no.6
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• pp.1043-1054
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• 2002

This paper intends to suggest a XML-based secure E-Procurement system using Unified Modeling Language(UML), as an application system for domestic automobile industry. Applying UML methodology, which is Component-based Development (CBD), we analyzed the workflow on procurement operation of automobile industry and implemented a prototype of efficient E-Procurement system for automobile industry, by developing XML/EDI and XML signature. Also, on this paper, object-oriented CBD is employed to minimize the risk of life cycle and reuse software as mentioned to limitation of information engineering methodology. It enables the interoperability with ERP (Enterprise Resource Planning) as corporate legacy system. This system proposes a solution to apply analysis and design of workflow, component development, interoperability with corporate information system, and XML signature for integrity and authentication of electronic documents in other system so far.

• Resources Recycling
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• v.21 no.3
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• pp.28-38
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• 2012

The purpose of this paper is to develop the alkali-activated concrete which uses 100% fly ash as a binder without any cement. The compressive strength of the mortar was examined depending on the chemical change in alkali-activator through SEM and SEM/EDS observations and the XRD analysis. It was found from the test that the higher molar concentration induced the greater effect on the initial strength, and that $Si^{4+}$ and $Al^{3+}$ were eluted relative to the compressive strength of mortar. In addition, it was confirmed that Al and Si were determined to be most influential ingredients on the microstructural development of the mortar, and that the different ingredient of the activator was almost no change in solidity from the XRD analysis.

• Journal of Conservation Science
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• v.29 no.3
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• pp.231-241
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• 2013

Analysis of the bronze bodhisattva from Pangyo-dong sites in Seongnam by computed tomography, ICP-AES, metallurgical microscope and SEM-EDS had to know manufacturing technique. And the origin of the raw material, was investigated using TIMS. Results with computed tomography, two bronze bodhisattva produced by lost-wax casting technique with hollow inside and could see the core of the inside. Result of component analysis and microstructure observation, material is alloy of copper-tin-lead and made by casting without artificial treatment. According to lead isotope ratio analysis result of bronze bodhisattva could be made into galena of the Gyeonggi massif in Korea South.

• Korean Journal of Community Nutrition
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• v.10 no.4
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• pp.484-492
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• 2005

The purposes of the study were to analyze nutrients of the menus served and to evaluate students' nutrient consumption at school food services. Three middle schools (boys, girls, and co-ed schools) were located in Seoul and Kyunggi Province. A weighed plate method was employed to measure plate wastes and consumption of the menus served. Data was collected for 3 consecutive days at each school. Nutrient analyses for the served and consumed menus were performed using CAN-PRO. On average the students consumed $67\%$ of the menus they were served. By menu category, the students consumed more than $90\%$ of the rice and one-dish foods they were served. Kimchis ($54\%$) and soups/stews ($55\%$) were the menu categories with the lowest consumption rates. The menus served at the boys and coed schools did not meet 1/3 of the recommended daily allowances (RDA) for calcium, iron, and vitamin $B_2$. Due to the plate wastes, the actual consumption of the boys school students did not meet the 1/3 RDA for calories, calcium, iron, vitamin A, vitamin $B_1$ vitamin $B_2$ and niacin. The menus served at the girls school exceeded the 1/3 RDA for all nutrients, but the actual consumption did not meet the 1/3 RDA for calcium, iron, and vitamin $B_2$. During the 3-day periods, the served and consumed menus provided $27\%$ and $24\%$ of energy from fat, which exceeded the recommended proportion of $20\%$. To improve nutrition management at school food services, dietitians should understand factors that influence students' consumption and implement nutrition education programs that emphasize balanced diets.

• Journal of the Korea Concrete Institute
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• v.21 no.5
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• pp.611-617
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• 2009

This paper reports an experimental study on the damage mechanism and resistance of Type I portland cement mortar and paste samples exposed to 5% sodium sulfate solution with different solution temperatures; namely, $4^{\circ}C$, $10^{\circ}C$ and $20^{\circ}C$. The resistance of mortar samples was evaluated using expansion, compressive strength and flexural strength measurements. Some microstructural observations such as x-ray diffraction, differential scanning calorimetry and scanning electron microscopy were also introduced to elucidate reactants formed by sulfate attack, especially in a low temperature condition. From the results, it was found that the degree of damage in the mortar samples was significantly associated with the temperature of sulfate solution. Low temperature of the sulfate solution led to the formation of thaumasite in mortar and paste samples, and subsequently a poor resistance to sulfate attack. Thus, it is noted that when concrete structures are exposed to sulfate media in the condition of a cold region or whether, special care should be taken.

• Analytical Science and Technology
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• v.8 no.2
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• pp.195-203
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• 1995

Carbon and small amounts of alloying elements were added in Fe-5.7% Al ferromagnetic damping alloy. The specific damping capacities(SDC) of these alloys were investigated in relation to the grain size and the magnetic hysteresis loops. The behavior of carbon was analysed by XRD and EDS. These alloys showed characteristic damping nature of ferromagnetic damping materials. The alloying elements decreased SDC and especially the carbon was remarkable. The SDC was observed to be not related with the grain size but with the magnetic hysteresis loop area. The remarkable decrease of SDC by carbon addition was attributed to the locking migration of $90^{\circ}$ magnetic domain wall by the interstitial carbon in Fe-Al solid solution. However, the carbides also seems to decrease the SDC.

• Food Science and Biotechnology
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• v.14 no.5
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• pp.586-592
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• 2005

This study was performed to investigate the antioxidant effects of Korean soybean paste extracts (SPE) on 2,2-azobis (2-amidinopropane) dihydrochloride (AAPH)-induced liver damage in rats. Thirty healthy Sprague Dawley rats were selected and divided into 5 groups. Isoflavone contents were measured using HPLC technique. The antioxidant activity was measured in the plasma and liver of the rats with the following results. Levels of isoflavone in fermented soy paste, red pepper paste and soy sauce were 28.9, 30.3 and $3.4\;{\mu}g/g$ for daidzein and 244.3, 187.7 and $6.1\;{\mu}g/g$ for genistein, respectively. The activities of glutamate oxaloacetic transaminase (GOT) and glutamate pyruvate transaminase (GPT) were significantly higher in the AAPH-treated group in the SPE-AAPH group (p<0.05). The thiobarbituric acid reactive substance (TBARS) production was significantly increased in the AAPH-treated liver tissue (P<0.05). Glutathione peroxidase (GPx), glutathione reductase (GR) and catalase in the liver were significantly (p<0.05) decreased by AAPH administration. The glutathione (GSH) concentration was higher in the SPE-treated (Ed- confirm) group than in the control and other groups (p<0.05). These results suggest that SPE led to increased anti oxidative activities against AAPH-induced peroxyl radical.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.3
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• pp.680-684
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• 2006

This study was designed to investigate effects of KH-304 in improving erectile dysfunction (ED), particularly in terms of nitric oxide (NO)-cGMP pathways. After oral administration of the KH-304 water extract, 1OOmg, 300mg, 500mg or 700mg per 1 kg of Dody weigh for 10days, We examined the expression and activity of two enzyme: neuronal NO synthase (nNOS), endothelial NO synthase (eNOS) and that act upon the major NO-cGMP signaling pathway in penile tissue. Effect of KH-304 on COMP degradation was also examined using bovine vascular smooth muscle cells pretreated with an NO donor, S-nitroso-N-Acetylpenicillamine (SNAP), Also, it examined the endothelial NO synthase (eNOS) for seaching effecting period (100mg, 300mg/kg for 10 and 30days) and peak intracavernous pressures (ICPS) in penile tissues rabbit copus cavernosum contracted by 10-6 M phenylephrine. The severely reduced peak intracavernous pressures (ICPS) in penile tissues were restored completely after KH-304 treatment, and KH-304 treatment significantly made the latency period earlier. Furthermore, the penile expression levels of nNOS, eNOS dependent NOS activities and COMP concentrations were increased significantly in the KH-304 100, 300mg treated rats. These results suggest that KH-304 with high expression of NOS may be useful in erectile dysfunction.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.1
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• pp.52-61
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• 1997

This study was aimed to decrease AOX(Adsorbed Organic Halide Compounds) by applying bleaching methods of A(HNO$_3$ ＋ NaNO$_2$) and $D^{(H/L)}$(dual pH chlorine dioxide bleaching) to conventional OCEDED bleaching stages. And so we investigate the effects of NSA treatment and the influence of production rate of ion species in chlorine dioxide and pulp mixtures according to various pH as well as dual pH on pulp bleaching. Finally the effects of AOC_DED^{(H/L)}ED^{(H/L)}$ bleaching stage were investigated by measuring AOX, brightness, kappa number and viscosity of pulps. A stage was treated by using 4% $HNO_3$ and 0.05~2.0% $NaNO_2$ on pulp and $D^{(H/L)}$ stage was like that pulp mixed with chlorine dioxide solution was adjusted at pH 7.0 and reacted in pulp cosistency 3%, S~20min, $70^{\circ}C$, and then successively for 160~175min at pH 4.0. It was found that suitable $NaNO_2$ addition rate was at 0.6% where the brigtness of pulp was most higher and pulp viscosity was not decreased much. Chlorate ($CIO_3$) was decreased according to pH increase but chlorite($CIO_2$) was highly decreased according to pH increase. And chloride was slightly increased with pH increase. The applying of A and D^{(H/L)}$ bleaching stages to some various multiple bleaching stages ($AOC_DED^{(H/L)}/EopD^{(H/L)} etc.$) had good results that brightness was increased more 2~3% ISO than conventional method(OCEDEopD), but viscosity was dropped by only 1~2cps.