• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2005년도 가을 학술발표논문집 Vol.32 No.2 (2)
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• pp.70-72
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• 2005

데이터베이스 관리자는 효과적인 데이터베이스 관리를 위해 워크로드 특성을 잘 알아야 한다. 워크로드 특성은 데이터베이스 응용분야에 따라 다르며, 데이터베이스 환경에서 하나 이상의 응용 분야가 수행될 수 있다. 복합적인 데이터베이스 응용 분야 때문에, 관리자가 데이터베이스 시스템에서 발생하는 워크로드를 식별하기가 더욱 어려워졌다. 복합적인 데이터베이스 응용 분야의 효과적인 데이터베이스 관리를 수행하기 위해 워크로드를 식별할 수 있는 방법이 요구된다. 이를 위해, 본 연구는 TPC-C와 TPC-W 성능평가의 워크로드와 두 성능평가의 혼합된 워크로드들을 생성하여 워크로드 식별을 수행하였다. 워크로드 식별은 퍼지 k-NN 알고리즘을 수정하여 진행하였다. 수정된 k-NN 알고리즘은 혼합 비율에 따라 시험 워크로드 데이터와 훈련 워크로드 데이터간의 워크로드 식별 실험에 사용되었고, 분류를 위한 k-NN, 퍼지 k-NN, 분산 가중치 퍼지 k-NN 알고리즘의 결과와 비교되었다. 수정된 k-NN 알고리즘은 다른 알고리즘보다 k 인자에 따른 변동과 오차율이 감소하여 워크로드 식별에 더 적합함을 보였다. 본 논문의 결과는 복합된 데이터베이스 응용 분야의 특성을 보이는 데이터베이스 환경에서 워크로드 식별 정보를 창조하여 융통성 있는 튜닝 기법을 고려하는데 기여한다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.157-158
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• 2006

A novel nanofabrication process has been developed using two-photon crosslinking (TPC) for the fabrication of three-dimensional (3D) SiCN ceramic microstructures applicable to high functional 3D devices, which can be used in harsh working environments requiring a high temperature, a resistance to chemical corrosion, as well as tribological properties. After sequential processes: TPC and pyrolysis, 3D ceramic microstructures are obtained. However, large shrinkage due to low-ceramic yield during the pyrolysis is a serious problem to be solved in the precise fabrication of 3D ceramic microstructures. In this work, silica nanoparticles were employed as a filler to reduce the amount of shrinkage. In particular, the ceramic microstructures containing 40 wt% silica nanoparticles exhibited relatively isotropic shrinkage owing to its sliding free from the substrate during pyrolysis.

• Natural Product Sciences
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• 제29권2호
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• pp.83-90
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• 2023

To our knowledge, this is the first study aiming to optimize the extraction conditions of total phenolic compounds (TPC) and total flavonoids contents (TFC) from Argania spinosa leaves using Response Surface Methodology (RSM) with a Box-Behnken design (BBD). The optimal conditions obtained were 5% (w/v) solvent-to-solid ratio, 72.33% ethanol concentration, and 10h ours as an extraction time, which resulted in an extract with maximum TPC (131.63 mg GAE/g dw) and TFC (10.66 mg QE/g dw). Under the optimal extraction conditions, the antioxidant activity of the extracts of leaves of argan tree showed a moderate antiradical capacity of DPPH (IC₅₀ = 0,130 mg/mL) and ABTS (IC₅₀ = 0.198 mg/mL). However, the leaves of argan tree showed a very interesting reducing power of Iron (IC₅₀ = 0.448 mg/ml) which is similar to that of the ascorbic acid (IC₅₀ = 0.371 mg/mL).

• 한국미생물·생명공학회지
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• 제50권3호
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• pp.361-374
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• 2022

For this study, we designed and produced mulberry low-fat ice cream supplemented with synbiotics (MLF-ISS). The sensory characteristics and physical, chemical, and microbiological qualities of MLF-ISS were then determined. Mulberry juice inoculated with or without probiotic (Lactobacillus plantarum TISTR 926 and Saccharomyces boulardii CNCM I-745) was also tested at 37℃ for 24 h to determine probiotic growth rate, pH, total anthocyanin content (TAC), total phenolic content (TPC), and antioxidant activity (AA). Only the TAC of mulberry juice inoculated with S. boulardii CNCM I-745 increased considerably (p < 0.05) among these parameters. MLF-ISS was produced with varied mulberry fruit concentrations (0, 10, 20, 30, or 40%) (w/w). The MLF-ISS prepared with 30% mulberry fruit (w/w) (30-MLF-ISS) had a higher score in appearance, color, and sweetness (p < 0.05) when sensory qualities were measured using the 9-point hedonic scale method. In the CIE lab system (L^*, a^*, b^*), the color values of 30-MLF-ISS were 27.80 ± 0.26, 12.99 ± 0.59, and 1.43 ± 0.05, respectively. The 30-MLF-ISS was also subjected to a proximate analysis. The melting rate of 30-MLF-ISS was 0.29 ± 0.03 g/min and the time it took for the first drop to fall was 37.00 ± 7.00 min. TAC, TPC, and AA of 30-MLF-ISS were observed to alter significantly (p < 0.05) during varied intervals of storage at - 18℃ (0, 30, and 60 days). The viability of probiotics in 30-MLF-ISS slightly decreased after storage at -18℃ for 8 weeks, but remained about 6 log CFU/g. During storage at -18℃ for 0 and 120 days, no pathogenic bacteria were detected in 30-MLF-ISS. These findings show that 30-MLF-ISS has nutritional and functional value, is free of foodborne pathogenic bacteria, is safe for consumers' health, and is suitable for application in the ice cream and related food industries.

• 한국축산식품학회지
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• 제41권6호
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• pp.1078-1094
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• 2021

This research investigated the physio-chemical and microbial quality characteristics of dry fermented sausage from selected Pediococcus strains: P. acidiliactici (PE1) and P. pentosaceus (PE2) as compared to commercial starter culture (COS) during fermentation and ripening. Treatments showed no substantial variation (p<0.05) in water activity (a_w) values across the study period. PE1 and PE2 treatments exhibited similar (p>0.05) pH values and presented remarkable (p<0.05) lower volatile basic nitrogen (VBN) and thiobarbituric acid reactive (TBARS) content than COS treatment throughout the ripening period. However, the pH values in COS batch were considerably lower than others. PE1 samples presented a significant highest (p<0.05) counts both in lactic acid bacteria (LAB) and total plate count (TPC) than COS and PE2 treatments at 7 days fermentation, and it resulted in a similar and higher TPC count as COS after the ripening period. After the ripening process, treatments are ordered based on LAB counts as follows: COS>PE1>PE2. All batches presented similar redness and yellowness attributes since the 7 days of fermentation and in lightness across the study period. Treatments were similar (p>0.05) in springiness and chewiness traits across the study period and in hardness characteristics in the ripened products. Cohesiveness was higher in PE1 and COS batches. No variation (p>0.05) in aroma and sourness sensory attributes of treatments. The color attribute was highest (p<0.05) in PE1 and PE2 treatments and PE1 had the highest overall acceptability. The overall outstanding merit exhibited by PE1 can be utilized in the commercial production of high-quality dry fermented sausage.

• 한국전자거래학회지
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• 제11권4호
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• pp.33-48
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• 2006

XML이 웹상에서 데이타 교환의 표준으로 등장한 이래 웹 환경에서 e-Commerce와 같은 웹 기반 비즈니스 응용을 효율적으로 지원하기 위해 XML 웨어하우스 기술이 요구되고 있다. 관계 DMBS가 XML웨어하우스의 저장소로 사용될 경우, XML웨어하우스의 XML실체뷰는 관계 DBMS의 관계 실체뷰를 이용하여 제공할 수 있다. XML 문서가 관계 튜플로 저장되기 때문에 XML 실체뷰를 정의하는 XML 질의는 SQL로 변경된다. 만일 변경된 SQL문으로 관계 실체뷰를 정의하면, XML실체뷰는 해당 관계 실체뷰를 구성하는 튜플들에 대한 XML 태깅만으로 얻어질 수 있다. 이런 기법의 가장 큰 장점은, 소스 XML 문서가 변경될 때마다 XML 태깅을 제외한 XML 실체뷰의 일관성 유지를 관계 DBMS가 수행해준다는 것이다. 본 논문에서는 이러한 XML 실체뷰 기법을 제시하고 Windows 2000 Professional 환경에서 실체뷰 기능을 갖춘 상용 관계 DBMS를 사용하여 Java로 구현하였다. 성능 실험은 웹상의 e-Commerce 벤치마크인 TPC-W의 XML 문서를 대상으로 수행하였다. 실험 결과 본 논문이 제시한 XML 실체뷰 기법 이 매우 효율적 인 것으로 나타났다.

• Journal of Ecology and Environment
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• 제48권1호
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• pp.24-31
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• 2024

Background: Honey from different geographical origins can have distinct characteristics due to variations in the floral sources available to stingless bees in different regions. The most abundant stingless bee for meliponiculture in Thailand is Tetragonula pagdeni. However, only a few studies about the properties of honey from a different origin were carried out. The objective of this study was focused on a comparative study to evaluate the melissopalynological, physicochemical, antioxidant activities, and total phenolic contents (TPCs) of stingless bee honey produced by T. pagdeni from different parts of Thailand. Results: Fifty honey samples were collected from five locations, and the physicochemical properties of T. pagdeni honey samples are acidic (pH 3.02-4.15) and have a high water content (18.42-25.06 %w/w), which is related to the regions of meliponary. Melisopalynological analysis reveals the predominant pollen from Melaleuca quinquenervia, Cocus nuciferca, Nephelium lappaceum, Salacca wallichiana, and multiflora honey. All honey samples were analyzed for their TPC and 2,2-diphenyl1-picrylhydrazyl radical scavenging activity. The results show that all samples had high TPC and antioxidant activities with a strong correlation (p < 0.05). Conclusions: The data from this study indicates the importance of geographical origin, which links physicochemical properties, phenolic compounds, and functional characteristics to their floral. Besides, the floral sources and harvesting location affected the properties of stingless bee honey. Our results identify Melaleuca honey as a promising source of phenolic content and antioxidant activity that can be used as a functional food, as well as multiflora and Cocus honey. However, further studies are required to characterize the phenolic compound and its biological potential, which could be a stingless bee honey biomarker and quality control, simultaneously with the physicochemical analysis.

• 한국축산식품학회지
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• 제41권6호
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• pp.1036-1048
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• 2021

This study investigated the possible improvement in the antioxidative status and quality characteristics of ready-to-eat (RTE) Samgyetang after adding various black garlic (BG) extracts. The antioxidant activity, total phenolic content (TPC), total flavonoid content (TFC), meat quality indexes, and lipid oxidation rates were measured after receiving one of five different treatments consisting of conventional Samgyetang broth as a negative control, raw garlic (RG) extract as a positive control, BG, oven-dried BG, and maltodextrin-encapsulated BG extract as treatments. Employing retort cooking, fat trimmed carcasses were added to the initially prepared broth together with a phenolic extract that was set at 5% (w/w). A significant intensification of red and yellow color was observed in breast and thigh meat treated with BG extracts, regardless of pretreatment, compared to the negative control and RG. The moisture percentage was affected by the addition of BG extracts, where the encapsulation group retained the highest water content after retorting. In terms of antioxidative status, maltodextrin-encapsulated BG extract was as effective as an oven-dried extract to scavenge free radicals and showed the highest score among samples (p<0.01). The concentration of TFC was found to be the highest and did not differ between encapsulation and oven-dried groups, followed by BG, RG, and the negative control. However, the addition of encapsulated BG extract was the most effective in delaying the formation of malondialdehyde among the samples. Therefore, pre-treatment of BG extract through encapsulation is recommended to develop a higher antioxidative status and quality characteristics of Samgyetang.

• Journal of Nutrition and Health
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• 제52권3호
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• pp.250-257
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• 2019

본 연구에서는 섬쑥부쟁이 (Aster glehni)와 쑥부쟁이(Aster yomena)의 항산화 효과 및 항비만 효과를 검정하기 하여 물 (-W)과 에탄올 (-E)추출물을 이용하여 실험을 실히 하였다. 각 추출물을 총 페놀 및 총 플라보노이드를 함량을 분석하고 DPPH와 $ABTS^+$를 이용하여 항산화 활성을 비교 분석하였다. 또한 총 페놀 및 총 플라보노이드를 함량과 항산화 활성의 상관관계도 분석하였다. 항산화 물질로 알려진 총 페놀과 플라보노이드 함량은 섬쑥부쟁이의 70% 주정 추출물에서 각각 45.42 mg/g와 40.32 mg/g으로 다른 추출물에 비해 높은 함량을 나타내었다. 항산화 효과의 경우 또한 $ABTS^+$의 $IC_{50}$값이 섬쑥부쟁이의 70% 주정 추출물에서 $30.1{\mu}g/mL$로 가장 우수하였다. 총 페놀 및 총 플라보노이드를 함량과 항산화 활성의 상관관계도 유의적으로 통계처리 되어 추출물의 함량이 항산화 활성에 영향이 있다는 것을 보여주었다. 또한, 섬쑥부쟁이와 쑥부쟁이의 항비만 효능 평가를 위하여 지방세포인 3T3-L1의 분화 억제를 확인하였다. 추출물을 농도별로 처리하여 지방분화를 Oli-Red O 염색약으로 염색하여 비교하여 보았을 때, 섬쑥부쟁이의 물 추출물에서 70.49%의 가장 낮은 지질 축적율을 나타내었다. 이상의 결과에서, 섬쑥부쟁이의 총 페놀 및 총 플라보노이드를 함량, 항산화 활성과 지방분화 억제 활성이 우수하게 나타났다. 이에 본 연구결과를 바탕으로 섬쑥부쟁이가 안정성이 검증된 항비만 기능성 식품이나 의약품 소재로써 활용될 수 있을 것으로 기대된다.

• 한국식품영양과학회지
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• 제36권12호
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• pp.1491-1496
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• 2007

추출용매를 달리하여 마이크로웨이브로 추출한 머루의 생리활성을 측정하였다. 전자공여능, 아질산염 소거능은 모든 추출구에서 농도 의존적으로 활성이 증가하였고 폴리페놀도 농도 증가에 따라 함량이 높게 나타났다. 세 가지 추출용매 중 50% 에탄올 추출 시 항산화 활성이 높았는데 이는 총 폴리페놀 함량 측정 결과와도 일치하여 머루의 항산화 활성이 폴리페놀과 밀접한 관련이 있다고 사료된다. 전반적인 활성은 전자공여능이 약 $13{\sim}101%$로 특히 1.6 g/dL 농도의 50% 에탄올 추출물의 활성의 경우 1% L-ascorbic acid보다 우수했다. 아질산염 소거능은 pH가 낮을수록 활성이 높은 경향으로 pH 1.2에서 활성이 $34{\sim}99%$로 가장 높게 측정되었다. 총 폴리페놀 함량은 농도에 따른 폴리페놀 함량의 차이가 컸으며 50% 에탄올 추출, 1.6 g/dL 농도에서 약 38.76 mM gallic acid equivalent로 가장 높았다. SOD 유사활성은 $30{\sim}50%$로 전자공여능이나 아질산염 소거능만큼 우수하진 않았지만 0.01% L-ascorbic acid보다 50%, 100% 에탄올 추출구에서 높은 활성을 보였다. 머루의 항산화 활성과 폴리페놀 함량은 밀접한 관련이 있는 것으로 보이며 폴리페놀 함량이 풍부한 머루를 이용한 항산화 건강기능성 식품 개발의 기초 자료로 제공하고자 하였다.