• Journal of the Korean Recycled Construction Resources Institute
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• v.12 no.2
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• pp.135-142
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• 2024

The purpose of this study is to experimentally investigate the effect of water-binder ratio and fiber type on the compressive strength and tensile performance of fiber reinforced highly ductile composites. To achieve this, four different mixtures were prepared by varying the water-binder ratio and fiber type, and compression and tension tests were conducted. The test results showed that the influence of fiber type on compressive strength was minimal, however, the WB50 series mixture exhibited a 29 % lower strength compared to the WB40 series mixture, indicating a significant effect of the water-binder ratio. On the other hand, the effect of fiber type on tensile properties was found to be more significant than that of the water-binder ratio. Tensile strain capacity ranged from 2.9 % to 6.2 %, with PE series mixtures showing 1.63 to 2.14 times higher performance compared to PVA series mixtures. Additionally, the crack patterns of the PE series mixtures were superior than those of the PVA series mixtures.

• Food Science and Preservation
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• v.30 no.6
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• pp.1029-1042
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• 2023

This study aimed to apply the technology of increasing the volatile aromatic compounds in wine through mixed fermentation of Saccharomyces cerevisiae and non-Saccharomyces yeasts to make distilled soju. The expectation was to induce changes in metabolites such as volatile aromatic compounds before the distillation process, followed by concentrating these compounds through distillation to enhance the odor property of distilled soju. Additionally, the study aimed to examine the impact of mixed fermentation with S. cerevisiae and non-Saccharomyces yeasts on distilled soju's free amino acid content. As a result, when Hanseniaspora uvarum yeast was used, there was an increase in the content of low molecular weight volatile aroma compounds, particularly esters. Distilled soju co-fermented with S. cerevisiae and H. uvarum SJ69 exhibited similar amino acid content to distilled soju single-fermented with S. cerevisiae. However, distilled soju co-fermented with S. cerevisiae and H. uvarum S6, a decrease in amino acid content. Sensory evaluation results indicated a higher odor score in distilled soju co-fermented with S. cerevisiae and H. uvarum S6, suggesting that the mixed fermentation technology utilizing H. uvarum could contribute to improving the quality of distilled soju in the future.

• 전기의세계
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• v.43 no.11
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• pp.6-9
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• 1994

우리날의 대학생수는 지난 20년간 급격한 양적 팽창을 하여 인구비례로 미국, 호주에 이어 세계 제3위가 되었다. 4년제 대학도 157개나 되며 공과대학만도 61개, 산업대학이 6개가 있다. 공과계열의 학생수는 275,237명이며 교수는 전임강사 이상이 4,822명으로 학생대 교수의 비는 무려 57:1이나 된다. 대학전체 33:1, 국민학교 30:1, 중학교 26:1, 고등학교 24:1보다 훨씬 높은 숫자이다. 한편 93년도 졸업생수는 공학사 34,334명, 공학석사 5,243명, 공학박사 1,009명이나 되지만 산업계에서는 인력부족을 느끼는 기현상이 벌어지고 있다.

• Computational Structural Engineering
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• v.5 no.2
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• pp.18-27
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• 1992

88년 9월중에 한국과학기술연구원 시스템공학연구소가 당시의 슈퍼컴퓨터 중 최상위 성능을 가진 Cray-2S(4 CPU, 1GB)를 설치함에 따라 국내에도 슈퍼컴퓨터 시대가 열리게 되었으며, 90년 10월에 산업계에서는 최초로 기아자동차에서 Cray Y/MP(1CPU)를 설치한 이래 최근에 국방과학연구소, 삼성그룹에서도 Cray Y/MP계열의 슈퍼컴퓨터를 설치하여 과학기술 계산 및 공학해석에 폭넓게 활용할 전망이다. 따라서 본 고에서는 슈퍼컴퓨터의 정의 및 분류, 특징과 보급현황에 대하여 알아보고 슈퍼컴퓨터 및 병렬처리기술을 이용한 유한요소해석에 관하여 간략히 기술하고저 한다.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.1
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• pp.1-9
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• 1987

In this paper, the acquisition performance of a receiver that utilizes a non-coherent digital correlator is analyzed. In order to analyze the acquisition performance, the probability density function of a receiver output random variable has been derived approximately. Using this function, the acquisition performance of the coarse acquisition code receiver in a global positioning system is analyzed.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2020.10a
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• pp.150-150
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• 2020

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.37 no.6
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• pp.70-75
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• 2000

This paper examines the performance of adaptive filtering algorithms in relation to the asymptotic relative efficiency (ARE) of estimators. The adaptive filtering algorithms are Hybrid II and modified zero forcing (MZF) algorithms. The Hybrid II and MZF algorithms are simplified forms of the LMS algorithm, which use the polarity of the input signal, and polarities of the error and input signals, respectively. The ARE of estimators for each algorithm is analyzed under the condition of the same convergence speed. Computer simulations for adaptive equalization are performed to check the validity of the theory. The explicit expressions for the ARE values of the Hybrid II and MZF algorithms are derived, and its results have similar values to the results of computer simulation. It also revealed that the ARE values depend on the correlation coefficients between input signal and error signal.

• Applied Chemistry for Engineering
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• v.22 no.1
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• pp.48-55
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• 2011

It was found that the absorbent mixed with 2-aminoethanol and others has been applied to remove them via chemical neutralization. The absorbent of natural second metabolites was achieved by a removal efficiency of 20~30% by itself depending on treatment conditions, but the complex absorbent mixed with 0.2% amine chemical provides the removal efficiency of over 98%. Optimal removal efficiencies have been examined against two major parameters of the temperature and pH to remove ammonia and hydrogen sulfide gases. The chemical analysis was also performed to analyze the composition of an essential oil by GC-MS. The monoterpenes in an essential oil reacted with odorous compounds by neutralization and their reaction mechanism was partially elucidated.

• Composites Research
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• v.21 no.6
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• pp.15-22
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• 2008

Reversed plane bending fatigue tests were conducted on SiC particle aluminum composite. The initiation and growth behaviors of small surface fatigue cracks were continuously monitored by the replica technique and investigated in detail. The fatigue life of MMC is shorter than that of matrix because there exists interface debonding of SiC particles and matrix on the whole face of the notch part in the casting metal matrix composite(MMC). The coalescence of micro-cracks was observed in the tests conducted at high stress levels. Due to the coalescence, a higher crack growth rate of small cracks rather than those of long cracks was recognized in da/dn-$K_{max}$ relationship.

• Journal of KIISE:Software and Applications
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• v.34 no.3
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• pp.196-211
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• 2007

In the Product Line Engineering (PLE), current studies about an analysis of the feature have uncertain and ad-hoc criteria of analysis based on developer’s intuition or domain expert’s heuristic approach and difficulty to extract explicit features from a product in a product line because the stakeholders lack comprehensive understanding of the features in feature modeling. Therefore, this paper proposes a model of the analyzing commonality and variability of the feature based on the Ontology. The proposed model in this paper suggests two approaches in order to solve the problems mentioned above: First, the model explicitly expresses the feature by making an individual feature attribute list based on the meta feature modeling to understand common feature. Second, the model projects an analysis model of commonality and variability using the semantic similarity between features based on the Ontology to the stakeholders. The main contribution of this paper is to improve the reusability of distinguished features on developing products of same line henceforth.