• 한국산학기술학회논문지
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• 제19권2호
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• pp.483-496
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• 2018

국가직무능력표준, NCS(National Competency Standards)는 대학이나 기업체 모두에서 매우 중요한 이슈로 대두되고 있다. NCS는 그동안 직업훈련기관에서 주로 사용되어 왔으나 최근 들어 2,3년제 전문대학뿐만이 아니라 4년제 대학에서도 점차 관심을 가지고 있는 추세이다. 문제해결능력, 의사소통능력, 대인관계능력 등의 NCS의 직업기초능력과 같은 소프트스킬들은 기술이 비약적으로 발전하는 지식정보사회에서는 구체적인 기술능력보다 더욱더 중요성이 증대되고 있다. 본 연구는 NCS의 직업기초능력과 북미와 유럽 등지에서 캡스톤 디자인으로 많이 활용하고 있는 Formula SAE 활동과의 연관성을 대회 현지관찰조사, 학생들이 작성한 대회 관련 문서들 그리고 미국 링컨에서 열린 Formula SAE대회와 한국 KSAE 대회에 참가한 학생들을 대상으로 하는 설문 조사를 통하여 분석하였다. 결과에서 학생들이 참가한 Formula SAE 대회는 NCS 직업기초능력 항들과 전반적인 관점에서 밀접한 속성을 가진다는 것을 알 수가 있다. Formula SAE 활동이 NCS 직업기초능력 향상에 얼마나 도움이 되는가에 대한 설문조사에서 해외 및 국내 모두 전반적으로 리커트척도 5점 만점에 모두 4.0 이상의 점수를 나타내며 도움이 되는 것으로 나타났다. 참고로 양 대회 참가학생들 간에 수학적능력, 의사소통능력, 문제해결능력 항들은 통계적으로 유의미한 관계를 나머지 항들은 유의차가 없는 것으로 나타났다.

• Elastomers and Composites
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• 제16권1호
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• pp.3-13
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• 1981

The purpose of this dissertation is to study the physical properties of cellular rubber products for industrial use. Vulcanization characteristics were investigated by usingcure curve that had obtained by means of Rheometer. The results of physical properties, vulcanization characteristics and foaming states are as follows. 1. The test results for vulcanization characteristics of NR compounds indicated that in the recipe R-1. When accelerator D is used, the optimum conditions of vulcanizate are obtained, while formula R-2 and R-3 have shown higher torgue at curing time, $1{\sim}2$ minutes. Cellular rubber product test in terms of compression set and compression deflection has also met the requirements of SAE. 2. For SBR compounds, S-1 formula was the best in terns of vulcanization characteristics, and for the blowing structure of cellular rubber products, formula S-3 in which accelerator M is added was fair. All other test results, such as compression set and compression deflection properties met SAE requirements. 3. NBR compound (N-1) including accelerator TT was the best in terms of vulcanization characteristic and also blowing structure. All other properties listed above met requirements, particulary for oil resistance test. 4. In the test of EPDM compounds, when mixed accelerator, M and TT, is used(formula E-1) the best results were obtained. Since EPDM is hydrocarbon elastomer, oil resistance test failed. All other properties met the requirement specified in SAE.

• 한국수소및신에너지학회논문집
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• 제34권5호
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• pp.447-455
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• 2023

SAE J2601, hydrogen fueling protocols, proposes two charging methods. The first is the table-based fueling protocol, and the second is the MC formula-based fueling protocol. Among them, MC formula-based fueling protocol calculates and supplies the target pressure and pressure ramp rate (PRR) using the pre-cooling temperature of the hydrogen and the physical parameters of the tank in the vehicle. The coefficient of the MC formula for deriving MC varies depending on the physical parameters of the tank in the vehicle. However, most studies use the MC coefficient derived from SAE J2601 as it is, despite the difference in the physical parameters of the tank applied to the study and the tank used to derive the MC coefficient from SAE J2601. In this study, the MC coefficient was derived by applying the hydrogen tank currently used, and the difference with the fueling performance using the MC coefficient proposed in SAE J2601 was verified. In addition, the difference was confirmed by comparing and analyzing the fueling performance of the table-based method currently used in hydrogen fueling stations and the MC formula-based method using MC coefficient derived in this study.

• 한국축산식품학회지
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• 제43권4호
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• pp.659-673
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• 2023

Compared to infant formula, breast milk is the best source of nutrition for infants; it not only improves the neonatal intestinal function, but also regulates the immune system and gut microbiota composition. However, probiotic-fortified infant formula may further enhance the infant gut environment by overcoming the limitations of traditional infant formula. We investigated the probiotic formula administration for one month by comparing 118 Korean infants into the following three groups: infants in each group fed with breast milk (50), probiotic formula (35), or placebo formula-fed group (33). Probiotic formula improved stool consistency and defecation frequency compared to placebo formula-fed group. The probiotic formula helped maintaining the level of secretory immunoglobulin A (sIgA), which had remarkably decreased over time in placebo formula-fed infants (compared to weeks 0 and 4). Moreover, probiotic formula decreased the acidity of stool and considerably increased the butyrate concentration. Furthermore, the fecal microbiota of each group was evaluated at weeks 0 and 4. The microbial composition was distinct between each groups, and the abundance of health-promoting bacteria increased in the probiotic formula compared to the placebo formula-fed group. In summary, supplementation of probiotic infant formula can help optimize the infant gut environment, microbial composition, and metabolic activity of the microbiota, mimicking those of breast milk.

• Toxicological Research
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• 제26권1호
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• pp.53-59
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• 2010

This study was conducted to obtain acute information of the oral dose toxicity of DHU001, a polyherbal formula in male and female mice. In order to calculated 50% lethal dose ($LD_{50}$) and approximate lethal dose (LD), test material was once orally administered to male and female ICR mice at dose levels of 2000, 1000, 500, 250 and 0 (vehicle control) ml/kg (body weight). The mortality and changes on body weight, clinical signs, gross observation, organ weight and histopathology of principle organs were monitored 14 days after treatment with DHU001. We could not find any mortalities, DHU001 treatment-related clinical signs, changes on the body and organ weights, gross and histopathological findings. The results obtained in this study suggest that $LD_{50}$ and approximate LD in mice after single oral dose of DHU001 were considered over 2000 mg/kg in both female and male mice.

• 대한한의학회지
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• 제39권4호
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• pp.86-113
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• 2018

Objectives: We examined the effects of a mixed formula consisting of dried pomegranate concentrate powder (PCP) and the aqueous extracts of Eucommiae cortex (EC) and Achyranthis radix (AR) in rats with surgically induced osteoarthritis (OA). Methods: Two weeks after OA-inducing surgery, a PCP:EC:AR 5:4:1 (g/g) combination or single formula was orally administered. Changes in body weight, knee thickness, maximum knee extension angle, bone mineral density of the knee joints, femoral and tibial articular surfaces, and compressive strength of the femoral and tibial articular cartilage (AC) were assessed, along with the prostaglandin E2 level, 5-lipoxygenase, matrix metalloproteinase (MMP)-2 and MMP-9 activity, and chondrogenic gene mRNA expression in the femoral and tibial AC with the synovial membrane (SM). In addition, the number of cleaved poly(ADP-ribose) polymerase, cyclooxygenase and tumor necrosis factor-${\alpha}$-immunoreactive cells in the femoral and tibial AC with SM were monitored, and the rate of cell proliferation was determined with a 5-bromo-2'-deoxyuridine uptake assay. Results : The signs of surgically induced OA in rats were significantly inhibited by both PCP, EC and AR combined and single formulas. In particular, the combination formula-treated OA model rats showed dose-dependent, significantly increased inhibitory activity against all tested criteria compared with single formula-treated rats. Conclusions: Taken together, our results suggest that the combination formula synergistically increased the anti-OA effects of its components through anti-inflammatory and chondrogenic activity in rats with surgically induced OA. In addition, 200, 100 and 50 mg/kg combination formula treatments showed dose-dependent inhibitory activity against all of the tested criteria.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 하계종합학술대회 논문집
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• pp.216-220
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• 1989

Direct calculation algorithm for the elements of A matrix is suggested for a single machine connected to the infinite bus. Excitation system and power system stabilizer are included. When A matrix is partitioned into seven submatrices, we can identify the location of non-zero elements and formula for each element. No matrix inversion and multiplication are necessary.

• Toxicological Research
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• 제24권3호
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• pp.189-194
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• 2008

The effects of DHU001, a mixed herbal formula consisted of 7 types aqueous extracts for treating respiratory disorders were observed on xylene-induced acute inflammation. The xylene was topically applied 60 min after administration of 500, 250 and 125 mg/kg of DHU001, and all animals were sacrificed 2 hrs after xylene application. The changes on ear weights, histolopathological analyses of ear were evaluated and compared to those of indomethacin and dexamethasone(15 mg/kg treated)-Both of drugs are well-known by anti-inflammatory agents. Xylene application resulted in marked increases in induced ear weights as compared with intact control ear. Severe vasodilation, edematous changes of ear skin and increase in the thickness of the ear tissues, neutrophil infiltration as acute inflammation were detected in xylene-treated control ears at histopathological observation. However, these xylene-induced acute inflammatory changes were dose-dependently decreased by oral treatment of DHU001. Therefore, it is concluded that DHU001 has favorable anti-inflammatory effects on xylene-applicated acute ear inflamed mice.

• Toxicological Research
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• 제26권2호
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• pp.123-130
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• 2010

The effect of DHU001, a mixed herbal formula consisted of 7 types aqueous extracts for various respiratory disorders were evaluated on 2,4-dinitrofluorobenzene (DNFB)-induced contact dermatitis, type I allergic model. Contact dermatitis was induced by sensitization with dinitrophenyl-derivatized ovalbumin (DNP-OVA) and DNFB challenge as antigen. Two different dosages of DHU001 (300 and 150 mg/kg) were orally administered to DNP-OVA sensitization mice once a day for 7 days with reference material, dexamethasone (15 mg/kg, intraperitoneal treatment). End of 7 days oral administration of DHU001 extracts or intraperitoneal treatment of dexamethasone, the changes on the edematous changes and scratching behavior were measured. Immediate after DNFB challenge on ear or paw of DNP-OVA sensitized mice, increases of ear and paw thicknesses and weights were detected with anterior ear skin (dermis to epidermis) thickness and paw scratching behavior increases. However, these contact dermatitis signs induced by DNFB treatment were reduced by treatment of the both different dosages of DHU001 and dexamethasone, respectively. The results obtained in this study suggest that oral treatment of DHU001 extracts also has relatively favorable effects on contact dermatitis.

• 대한한의학회지
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• 제38권4호
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• pp.11-40
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• 2017

Objectives: We investigated whether a mixture of the main component of pomegranate concentrated powder (PCP) with appropriate proportions of Eucommiae Cortex (EC) and Achyranthis Radix (AR) could act synergistically as an effective treatment for osteoarthritis (OA). Methods: In order to evaluate the effects of PCP, EC, and AR against OA, knee thicknesses, maximum extension angle of each knee, anti - inflammation effects, the transcript levels of chondrogenic genes mRNA expressions in femur and tibia articular cartilage (AC) with synovial membrane (SM) were analyzed. In addition, the histopathology and immunohistochemistry of the femur and tibia AC or SM were performed. Results: The surgically-induced OA signs in rats were significantly inhibited by 28 days of continuous treatment of PCP, EC and AR single formulas, and PCP with EC:AR mixed formulas. Especially, PCP with EC:AR 4:1, 2:1 and 1:1 mixed formula treatment constantly showed significantly more favorable inhibitory activities, as compared with those of single formula of PCP, EC and AR treated rats. Conclusion: PCP and EC:AR 4:1 mixed formula showed similar OA refinement effects through potent anti-inflammatory pathways as compared with those of diclofenac treatment, and showed additional chondrocyte proliferating effects on the both femur and tibia AC.