• Journal of Electrochemical Science and Technology
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• 제12권2호
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• pp.246-256
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• 2021

Mo,Cu-doped CeO₂ (CMCuO) nanopowders were synthesized by the nitrate-fuel combustion method aiming to improve the electrical and electrochemical properties of its Mo-doped CeO₂ (CMO) parent by the addition of copper. An electrical conductivity of ca. 1.22·10^-2 S cm^-1 was measured in air at 800℃ for CMCuO, which is nearly 10 times higher than that reported for CMO. This increase was associated with the inclusion of copper into the crystal lattice of ceria and the presence of Cu and Cu₂O as secondary phases in the CMCuO structure, which also could explain the increase in the charge transfer activities of the CMCuO based anode for the hydrogen and carbon monoxide electro-oxidation processes compared to the CMO based anode. A maximum power density of ca. 120 mW cm^-2 was measured using a CMCuO based anode in a solid oxide fuel cell (SOFC) with YSZ electrolyte and LSM-YSZ cathode operating at 800℃ with humidified syngas as fuel, which is comparable to the power output reported for other SOFCs with anodes containing copper. An increase in the area specific resistance of the SOFC was observed after ca. 10 hours of operation under cycling open circuit voltage and polarization conditions, which was attributed to the anode delamination caused by the reduction of the Cu₂O secondary phase contained in its microstructure. Therefore, the addition of a more electroactive phase for hydrogen oxidation is suggested to confer long-term stability to the CMCuO based anode.

• 한국식품저장유통학회지
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• 제20권5호
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• pp.608-613
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• 2013

국내에서 주로 수입되고 있는 Cabernet Sauvignon 레드와인(미국산 5종, 칠레산 10종)의 이화학적인 품질 특성과 항산화활성 및 폴리페놀 화합물의 조성을 조사하였다. 가용성 고형분은 7.03~8.6 $^{\circ}Brix$, 환원당은 2.7~6.7 g/L, 산도는 0.7~0.8% 범위이었으며, 미국산과 칠레산의 유의적인 차이는 없었다(p<0.05). 이산화황 함량은 미국산이 33 mg/L, 칠레산이 45 mg/L로 칠레산이 높았다(p<0.05). DPPH 방법과 ORAC 방법에 의한 항산화 활성과 총페놀 함량은 미국산보다 칠레산이 조금 높았으나 유의적인 차이는 없었다(p<0.05). 산 가수분해 방법으로 레드 와인 중의 폴리페놀 화합물을 HPLC로 분석한 결과 gallic acid, catechin, syringic acid, p-coumaric acid, quercetin, kaempferol의 6종이 확인되었으며, 이 중 catechin의 함량이 가장 높았고 폴리페놀화합물의 총 함량은 칠레산이 미국산에 비하여 높았다(p<0.05). 미국산과 칠레산 Cabernet Sauvignon 와인의 이화학적 특성과 항산화능은 이산화황 함량과 폴리페놀화합물의 함량이외에는 유의차가 없었다(p<0.05).

• Asian Pacific Journal of Cancer Prevention
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• 제15권23호
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• pp.10277-10280
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• 2015

Background and Aim: Breast cancer (BC) is a heterogeneous disease and cell proliferation markers may help to identify subtypes of clinical interest. We here analyzed the correlation between cell proliferation determined by Ki67 and HG in BC patients undergoing preoperative chemotherapy (PCT). Materials and Methods: We obtained clinical/pathological data from patients with invasive BC treated at our institution from 1999 until 2012. Expression of estrogen receptor (ER), progesterone receptor (PR), epidermal growth factor receptor type 2 (HER2) and Ki67 were determined by immuno-histochemistry (IHC). Clinicopathological subtypes were defined as: Luminal A, ER and/or PR positive, HER2 negative, HG 1 or 2; Luminal B, ER and/or PR positive, HER2 negative or positive and/or HG 3; triple negative (TN), ER, PR and HER2 negative independent of HG; HER2 positive, ER, PR negative and HER2 positive, independent of HG. By using Ki67, a value of 14% separated Luminal A and B tumors, independently of the histological grade. We analyzed correlations between Ki67 and HG, to define BC subtypes and their predictive value for response to PCT. Results: 1,560 BC patients were treated in the period, 147 receiving PCT (9.5%). Some 57 had sufficient clinicopathological information to be included in the study. Median age was 52 years (26-72), with 87.7% invasive ductal carcinomas (n=50). We performed IHC for Ki67 in 40 core biopsies and 50 surgical biopsies, 37 paired samples with Ki67 before and after chemotherapy being available. There was no significant correlation between Ki67 and HG (p=0.237), both categorizing patients into different subtypes. In most cases Ki67 decreased after PCT (65.8%). Only 3 patients had pathologic complete response (cPR). Conclusions: In our experience we did not find associations between Ki67 and HG. Determination of clinicopathological luminal subtypes differs by using Ki67 or HG.

• 한국식품조리과학회지
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• 제26권6호
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• pp.753-760
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• 2010

한국산 고춧가루를 이용한 수출용 고부가가치 육류 고추분말 복합조미료를 개발 하였다. 한국산 고추분말가루를 이용하여 복합조미료 개발 시 한국산 고춧가루는 미생물의 부패정도가 적어 위생적이고 한국 고유의 재료인 유자, 단호박, 버섯을 혼합하여 외국 조미료에 비해 맛의 차별화를 두었다. 수출용 육류 고추복합조미료(AI)는 한국산 고춧가루(20%), 오레가노, 파슬리, 타임 등의 총 허브류(26.1%), 소금(11.4%), 버섯, 마늘, 각각 8.5%로 구성되었고 그 외 흑후추, 파프리카, 단호박, 유자 등을 첨가하여 제조하였다. 미국인을 대상으로 한 관능평가에서 AI(고춧가루, 오레가노, 파슬리, 타임, 흑후추, 소금, 버섯, 커리, 유자, 파프리카, 단호박 및 마늘)은 미국산 고추 복합조미료제품보다 높은 선호도를 나타냈다. 따라서 해외 시장에 적극적으로 대처할 수 있는 한국산 고추의 새로운 가공식품 분야로서 가능성을 제시하였다.

• Endocrinology and Metabolism
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• 제33권4호
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• pp.466-472
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• 2018

Background: Thyroid dysfunction is associated with negative neonatal and obstetric outcomes. Large differences in thyroid function reference intervals exist across different populations. These differences can be explained by population-specific factors, such as iodine status. Many countries in Latin America report iodine sufficiency, but relatively few countries have published up-to-date data on iodine levels and thyroid function in the overall population, and especially in pregnant women. We evaluated the iodine status of pregnant women in Chile and determined thyroid hormone reference ranges in this population. Methods: This was a prospective observational study of healthy Chilean women at their first prenatal visit before week 14. Thyroid-stimulating hormone (TSH), total thyroxine ($T_4$), free $T_4$, antithyroid peroxidase antibody (TPOAb), and iodine levels from spot urine samples were measured. Iodine status and the reference ranges for TSH were calculated. Results: A total of 1,022 pregnant women in the first trimester were selected. Urinary iodine levels were measured in 302 randomly-selected women. The median urinary iodine concentration was $173.45{\mu}g/L$ (interquartile range, 108.11 to 249.35).The reference ranges of TSH were calculated in 670 patients selected according to the National Academy of Clinical Biochemistry guidelines. The median TSH level was $1.88{\mu}IU/mL$ (2.5th percentile: 0.13 to 97.5th percentile: 5.37). Using the reference range in the 1,022 women, the prevalence of clinical hypothyroidism was 1.76%, and that of subclinical hypothyroidism was 3.92%. TPOAb positivity was more common in women with TSH levels above $3.5{\mu}IU/mL$. Conclusion: We found adequate iodine intake and a right-shifted distribution of serum TSH levels in pregnant women in Chile. The prevalence of hypothyroidism in our sample of pregnant women was higher than has been described in the literature.

• ETRI Journal
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• 제35권1호
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• pp.89-99
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• 2013

The problem of the sentence-based pronunciation evaluation task is defined in the context of subjective criteria. Three subjective criteria (that is, the minimum subjective word score, the mean subjective word score, and first impression) are proposed and modeled with the combination of word-based assessment. Then, the subjective criteria are approximated with objective sentence pronunciation scores obtained with the combination of word-based metrics. No a priori studies of common mistakes are required, and class-based language models are used to incorporate incorrect and correct pronunciations. Incorrect pronunciations are automatically incorporated by making use of a competitive lexicon and the phonetic rules of students' mother and target languages. This procedure is applicable to any second language learning context, and subjective-objective sentence score correlations greater than or equal to 0.5 can be achieved when the proposed sentence-based pronunciation criteria are approximated with combinations of word-based scores. Finally, the subjective-objective sentence score correlations reported here are very comparable with those published elsewhere resulting from methods that require a priori studies of pronunciation errors.

• 전산구조공학
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• 제5권1호
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• pp.91-96
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• 1992

내진구조는 건축규준에 의하여 강제성을 띤 이후 많은 발전을 하였으나 아직도 완전하게 이해되지는 않고 있다. 본 논문은 실제로 발생하였던 두 지진의 지반운동을 10층의 철골조에 적용시켜 얻은 결과를 비교하였다. 1989년 California의 Loma Prieta에서 발생한 규모 7.1의 지진기록 12세트와 1985년 Chile의 Valparaiso에서 발생한 규모 7.8의 지진기록 9세트를 UBC의 지진지역 2B에 알맞게 조절하였다. 비슷한 규모를 가진 두 지진의 지반변위를 건물에 직접 적용시켜서 비교한 결과 그 지속시간이 긴 Chile지진이 상대적으로 지속시간이 짧은 California지진보다 약 2배 정도 큰 영향을 건물에 미치는 것이 발견되었다. 내진구조의 설계에 있어서 최대지반운동과 더불어 지반운동의 지속시간도 매우 중요하게 고려되어야 할 사항이다.

• ETRI Journal
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• 제32권3호
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• pp.395-405
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• 2010

A novel multiclassifier system (MCS) strategy is proposed and applied to a text-dependent speaker verification task. The presented scheme optimizes the linear combination of classifiers on an on-line basis. In contrast to ordinary MCS approaches, neither a priori distributions nor pre-tuned parameters are required. The idea is to improve the most accurate classifier by making use of the incremental information provided by the second classifier. The on-line multiclassifier optimization approach is applicable to any pattern recognition problem. The proposed method needs neither a priori distributions nor pre-estimated weights, and does not make use of any consideration about training/testing matching conditions. Results with Yoho database show that the presented approach can lead to reductions in equal error rate as high as 28%, when compared with the most accurate classifier, and 11% against a standard method for the optimization of linear combination of classifiers.

• Asia pacific journal of information systems
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• 제24권4호
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• pp.417-441
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• 2014

Organizations need to exhibit characteristics of agility to stay ahead of their competitors and to survive in dynamic environments. One major concern for organizations is how to implement Information Systems (ISs) to enhance their agility. Organizations tend to spend too many resources to change their entire IS instead of only the components that cause problems without exactly knowing whether it enables or suppress organizational agility. To address these shortcomings and practical issues, we provide a framework to assess organizational agility and to diagnose a problem related to IS. By applying this prototype of the Agility Framework, we were able to diagnose a problem that the department of Management Control and Information Systems at the Universidad de Chile had and planned actions for them to improve its organizational agility with a course scheduling system, eClasSkeduler. This action research, which took more than 25-month for the first cycle, further develops the Agility Framework, which not only provides a way to link IS with organizational functions but also illustrates how to use it to diagnose a situation and plan actions for improving organizational agility through an information system.

• Advances in Computational Design
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• 제8권2호
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• pp.113-131
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• 2023

The use of fibers has been commonly considered in engineered cementitious composites, but their behavior with coarse aggregate in concrete has not been studied significantly, which is needed to meet structural performance objectives for design, such as ductility. This research analyzes the behavior of fiber-reinforced concrete with coarse aggregate with 0.62%, 1.23%, and 2% PVA (Polyvinyl-alcohol) content, varying the maximum aggregate size. Tensile (direct and indirect) and compressive concrete tests were performed. The PVA fiber addition in coarse aggregate concrete increased the ductility in compression, especially for the fiber with a larger aspect ratio, with a minor impact on strength. In addition, the tensile tests showed that the PVA fiber increased the tensile strength of concrete with coarse aggregate and, more significantly, improved the ductility. A selected mixture was used to build short and slender reinforced concrete beams to assess the behavior of structural members. PVA fiber addition in short beams changed the failure mode from shear to flexure, increasing the deflection capacity. On the other hand, the slender beam tests revealed negligible impact with the use of PVA.