• 한국농공학회논문집
• /
• 제46권6호
• /
• pp.61-69
• /
• 2004

The aim of the work described in this paper was to confirm the application of the equation of the soil-water characteristic curves on an unsaturated soil. A series of suction test for unsaturated soils was conducted on the selected 4 kinds of soil using modified pressure extractor apparatus. And it was carried out to analyse The experimental parameters which can be describe the soil-water characteristics, were determined by using the data obtained from the experiment. From the results, it was found that The matric suction varied according to the grain size distribution, amount of fine grain particles and void ratio. Also it was found that the residual degree of saturation was decreased with in crease of the void ratio, but the pore size distribution index and air entry value were increased with in crease of the void ratio. And The application of the soil-water characteristic curve equation was confirmed for the various conditions and the various state by the comparison between the measured degree of saturation and the predicted degree of saturation.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1998년도 가을 학술발표대회 논문집(III)
• /
• pp.883-887
• /
• 1998

Hydration is the main reason for the growth of the material properties. A exact parameter to control the chemical and physical process is not the time, but the degree of hydration. Therefore, it is reasonable that development all material properties should be formulated in terms of degree of hydration. Mathematical formulation of degree of hydration is based on combination of reaction rate functions. The effect of moisture conditions as well as temperature on the rate of reaction is considered in the degree of hydration model. This effect is subdivided into two contributions: water shortage and water distribution. The former is associated with the effect of on the progress of hydration. The water needed for progress of hydration do not exist and there is not enough space for the reaction products to form. The latter is associated with the effect of free capillary water distribution in the pore system. Physically absorption layer does not contribute to progress of hydration and only free water is available for further hydration.

• Computers and Concrete
• /
• 제22권1호
• /
• pp.53-62
• /
• 2018

Cracking of concrete cover induced by reinforcement corrosion is a critical issue for life-cycle design and maintenance of reinforced concrete structures. However, the critical degree of corrosion, based on when the concrete surface cracks, is usually hard to predict accurately due to the heterogeneity inherent in concrete. To investigate the influence of concrete heterogeneity, a modified rigid-body-spring model, which could generate concrete sections with randomly distributed coarse aggregates, has been developed to study the corrosion-induced cracking process of the concrete cover and the corresponding critical degree of corrosion. In this model, concrete is assumed to be a three-phase composite composed of coarse aggregate, mortar and an interfacial transition zone (ITZ), and the uniform corrosion of a steel bar is simulated by applying uniform radial displacement. Once the relationship between radial displacement and degree of corrosion is derived, the critical degree of corrosion can be obtained. The mesoscale model demonstrated its validity as it predicted the critical degree of corrosion and cracking patterns in good agreement with analytical solutions and experimental results. The model demonstrates how the random distribution of coarse aggregate results in a variation of critical degrees of corrosion, which follows a normal distribution. A parametric study was conducted, which indicates that both the mean and variation of critical degree of corrosion increased with the increase of concrete cover thickness, coarse aggregates volume fraction and decrease of coarse aggregate size. In addition, as tensile strength of concrete increased, the average critical degree of corrosion increased while its variation almost remained unchanged.

• 유통과학연구
• /
• 제22권3호
• /
• pp.71-81
• /
• 2024

Purpose: This study examines the impact of inclusive policies and green transformation on regional development of mining areas. Research design, data and methodology: We designed and utilized a structured questionnaire to collect data from a population of 300 individuals. The questionnaire was disseminated through Google Forms and consisted of five questions for each research variable. A total of 210 respondents completed the questionnaire, yielding a response rate of 70%. The sample was diverse in terms of gender and educational level Of the 210 respondents, 113 were female (53.8%) and 97 were male (46.2%). In terms of educational background, the sample was composed as follows: 13 individuals with a Doctorate degree (6.2%), 56 with a Master's degree (26.7%), 97 with a Bachelor's degree (46.2%), 22 with a Diploma (10.5%), and 22 with a High School education (10.5%). Results: The research outcomes highlight the significant influence of inclusive policies on driving the Distribution of green economic transformation. Emphasizing the pivotal role of inclusive distribution strategies, especially within the context of mining areas, the study sheds light on their crucial contribution to fostering regional development. Conclusion: These findings hold valuable implications for policymakers, industry stakeholders, and academics promoting environmentally conscious economic transformations.

• 수산경영론집
• /
• 제36권2호
• /
• pp.1-24
• /
• 2005

The purpose of the study are summarized as follows : First, it has researched the possibility of the Distribution Information application in Sea Food Wholesale Market. Second, the effects which the Wholesale Market Company and the Intermediary Wholesaler Corporations can obtain in Sea Food Wholesale Market by building up a Distribution Information are classified into the effects of task, cost, and competition. It has analyzed the influence of these effects in direct and indirect Trust between the Wholesale Market Company and the Intermediary Wholesaler. Third, it has recognized the upcoming problems in Sea Food Wholesale Market by building up a Distribution Information, and it has suggested a plan to make the Distribution Information application successful in Sea Food Wholesale Market. This study has used a questionnaire to verify 5 hypotheses. Research model, factor analysis, correlation relationship analysis. The result of this study are summarized as follows : Building up the Distribution Information influences positively on the effectiveness of task, cost and competitiveness regardless of it being the Wholesale Market Company or the Intermediary Wholesaler corporation. However, the results of this analysis are to verify differences according to the degree of construction of the Distribution Information and the degree of the perception of the problems between the Wholesale Market Company and the Intermediary Wholesaler corporations have shown that there were distinct differences in the degree of computerization and of efforts to build a Distribution Information. Also there were distinct differences according to the degree of perceiving problems relating to building up the Distribution Information and the stages of the Distribution Information between the Wholesale Market Company and the Intermediary Wholesaler corporations. This study suggest three important steps that will help to establish a successful Distribution Information. First, the Wholesale Market Company and the Intermediary Wholesaler corporations should make efforts to increase mutual profits in partnership, and make direct Trust by sharing mutual information. Second, the lack of understanding of the Distribution Information between departments within the company requires educating employees about the Distribution Information. It is necessary to expand the communication networks of the Distribution Information between the Wholesale Market Company and the Intermediary Wholesaler. Third, mutual exchange of Information should be possible to offer systematic exchange of Information between the Wholesale Market Company and the Intermediary Wholesaler corporations.

• 대한산업공학회지
• /
• 제40권1호
• /
• pp.1-7
• /
• 2014

We consider a human contact social network that has connections through cellphone addresses. To construct such a social network, we use real call records provided by a large carrier, and connect to each other if there exists a call record between any two cellphone users. Due to its huge amount of data, we down-sample it in a way that the smallest-degree nodes are removed, in turn, from the network. For a moderate size of the networks we show that the degree distribution of the network follows a power-law distribution via linear regression analysis, implying the so-called scale-free property. We finally suggest some alternative measures to analyze a social network.

• 산업식품공학
• /
• 제21권4호
• /
• pp.341-350
• /
• 2017

The relationship of in vitro starch digestibility and gel strength was investigated at various concentrations (10-30%) of rice cultivars with different amylose contents (27.9, 17.9, and 5.2%). As the rice flour concentration increased, predicted glycemic index decreased, but gel strength increased regardless of amylose contents. Gel strength correlated strongly with amylose content, whereas in vitro starch digestibility was more highly affected by rice flour concentration than by amylose contents. Moreover, the impact of degree of gelatinization on in vitro starch digestibility of high amylose rice was also examined in terms of structural features and rheological properties. The digestion rate of fully gelatinized flour was 1.7 times higher than that of native flour, while the disrupted structure with a different gelatinization degree during starch digestion was visually demonstrated through the X-ray diffraction and molecular distribution analysis. The rice flour changed from an A-type to a V-type pattern and showed difference in crystalline melting. The low molecular weight distribution increased with increasing degree of gelatinization during starch digestion. The apparent viscosity also increased with degree of gelatinization. These results demonstrated that the starch digestibility of rice was more affected by concentration than by amylose content, as well as by the degree of gelatinization due to structural difference.

• 한국정보전자통신기술학회논문지
• /
• 제10권5호
• /
• pp.372-379
• /
• 2017

소프트웨어 개발과정동안 소프트웨어 신뢰성 요인은 매우 기본적인 사항이다. 소프트웨어 고장파악을 위한 무한고장 비동질적인 포아송 과정을 이용할 때 고장발생률 혹은 위험함수가 일정하거나 증가 또는 감소하는 속성을 가진다. 본 논문에서는 소프트웨어 신뢰 성능에 관한 효율성을 비교하는 자유도에 의존하는 카이제곱 분포를 적용한 신뢰성 모형을 제안하였다. 효율적인 모형을 평가하기 위하여 평균제곱오차(MSE)와 결정계수($R^2$)를 이용하고 최우추정법과 수치 해석적 방법을 사용하여 모수추정 알고리즘이 수행되었다. 제안하는 카이제곱분포의 자유도를 이용한 신뢰성 모형을 위해 실제 고장 간격 데이터를 사용한 고장 성능 분석이 적용되었다. 고장데이터 분석은 카이제곱분포의 자유도에 근거한 강도함수를 기준으로 비교되었다. 데이터 신뢰성을 확인하기 위하여 라플라스 추세검정이 적용되었다. 본 연구에 제안된 카이제곱분포의 자유도는 다양한 고장현상을 표현 할 수 있기 때문에 (결정계수가 90% 이상), 신뢰성 분야에서 활용 할 수 있는 모형으로 활용 할 수 있다. 이 연구 결과를 적용하면 소프트웨어 개발 설계자에게 다양한 자유도를 적용하여 소프트웨어 고장패턴을 예측함으로서 효율적인 모형을 개발하는데 표준 지침으로 적용 할 수 있다.

• 보존과학연구
• /
• 통권25호
• /
• pp.75-92
• /
• 2004

The conservation treatments of 10-storied pagoda in the temple of Kyoungchunsa is progressed favorably to come to the finish since 1995. Most of all, the important conservation treatments are stone crack, exfoliation and partial form modification. This pagoda has been made up a complicated structure constructed using 142 stones. Therefore, the stone crack and exfoliation have been occurred as very varied forms. Especially, the stylobate of the pagoda has 19 substitution stones of 48 stones, which is40% of modern stone substitution. It is supposed that there is serious weathering on the stones. The other stones, which are no substitution stones, have some kinds of weathering and so we carried out inside replenishment and partial outside reconstruction of crack stones using high molecular resin and substitution stone. The stone of each storey has also partial difference, but the condition of serious weathering on the whole. We can detect general degree through treatment of high molecule resin or distribution research of contaminated material on 10-storied pagoda in the temple of Kyoungchunsa. Especially, we are able to analyze general weathering degree and know details weathering of each storey or direction for the difference of replenishment quantity and different pattern of stone crack degree. Also, the distribution research will accomplish very important parts of examining environment effects and use as research data of cultural heritage conservation field.

• 융합보안논문지
• /
• 제23권2호
• /
• pp.3-10
• /
• 2023

웹에 존재하는 악성코드 배포 네트워크에는 악성코드 배포를 위해 핵심 역할을 수행하는 중심 노드가 있다. 이노드를 찾아 차단하면 악성코드 전파를 효과적으로 차단할 수 있다. 본 연구에서는 복잡계 네트워크에서 위험 분석이 적용된 centrality 검색 방법을 제안하였고, 이 방식을 통해 악성코드 배포 네트워크 내에서 핵심노드를 찾는 방법을 소개한다. 그 외에, 정상 네트워크와 악성 네트워트는 in-degree와 out-degree 측면에서 큰 차이가 있고, 네트워크 레이아웃 측면에서도 서로 다르다. 이 특징을 통해 우리는 악성과 정상 네트워크를 분별할 수 있다.