• Journal of the Korean Wood Science and Technology
• /
• 제20권2호
• /
• pp.81-90
• /
• 1992

The effect of acid treatment of cellulose on the substitution charateristics of carboxymethylation was studied in this paper. Five samples of hydrocellulose(HC), all prepared from ${\alpha}$-cellulose by hydrolysis with five reaction times and determined on average molecular weight and polydispersity, were carboxymethylated to carboxymethyl cellulose (CMC). The CMCs from HCs were examined upon degree of substitution(DS), distribution of carboxymethyl groups in anhydroglucose units of the cellulose, and unsubstituted anhydroglucose(USAG) content. The DS of CMCs increased with increasing the hydrolysis time except CMC from HC at 1 hour hydrolysis time. In carboxymethylation the availability of hydroxyl groups on anhydroglucose units in HCs was the highest on OH(2), and the relative availability of OH(6) increased with the increasing of the hydrolysis time. The USAG contents were more deviated than that calculated based on Spurlin's model, and had a strong tendency of decreasing with increasing the hydrolysis time. The reactivity of HC was lower than that of ${\alpha}$-cellulose and the relative availability of OH(6) in HC increased with the hydrolysis time.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제9권10호
• /
• pp.4204-4222
• /
• 2015

Cloud is the latest buzz word in the internet community among developers, consumers and security researchers. There have been many attacks on the cloud in the recent past where the services got interrupted and consumer privacy has been compromised. Denial of Service (DoS) attacks effect the service availability to the genuine user. Customers are paying to use the cloud, so enhancing the availability of services is a paramount task for the service provider. In the presence of DoS attacks, the availability is reduced drastically. Such attacks must be detected and prevented as early as possible and the power of computational approaches can be used to do so. In the literature, machine learning techniques have been used to detect the presence of attacks. In this paper, a novel approach is proposed, where intelligent rule based feature selection and classification are performed for DoS attack detection in the cloud. The performance of the proposed system has been evaluated on an experimental cloud set up with real time DoS tools. It was observed that the proposed system achieved an accuracy of 98.46% on the experimental data for 10,000 instances with 10 fold cross-validation. By using this methodology, the service providers will be able to provide a more secure cloud environment to the customers.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제28권5호
• /
• pp.68-77
• /
• 2023

The effect of soil damage on the physicochemical characteristics and activity of the soil microbial community is not well known. This study investigates this relationship by analyzing 11 soil samples collected from various points of soil damage across Gyeonggi-do. Soil damage resulted from forest fires, landslides, and development areas, with their impacts most severe on the topsoil layer (0-30 cm). Dehydrogenase and β-glucosidase activities were notably higher at locations damaged by forest fires compared to other sites. While enzyme activities in soils influenced by landslides and development areas were relatively low, sites with a pollution history exhibited elevated dehydrogenase activity, likely due to past microbial response to the pollution. Additionally, an assessment of carbon substrate usability by soil microorganisms indicated higher substrate availability in areas impacted by forest fires, contrasting with lower availability in landslide and development sites. Statistical analysis revealed a positive correlation between organic content of sand and clay and microbial activity. These findings provide valuable insights into soil damage and associated restoration research, as well as management strategies.

• 디지털융복합연구
• /
• 제17권6호
• /
• pp.145-157
• /
• 2019

본 연구는 스마트팜의 수용의도에 미치는 영향요인들을 살펴보고 이를 바탕으로 스마트팜 확산을 위한 제언을 하고자 하였다. 실제 농업에 종사하고 있는 농업인 대상으로 수집한 설문결과를 SPSS v22.0 및 Process Macro v3.0를 활용한 자료분석에 사용하였으며, 독립변수로는 스마트팜의 기술적 특성으로 가용성, 신뢰성, 경제성을 선정하여 종속변수인 수용의도에 미치는 영향을 분석하였고, 노력기대의 매개효과를 분석하였다. 연구결과, 기술적 특성 중 가용성과 경제성은 수용의도에 정(+)의 영향을 미치며, 신뢰성은 수용의도에 영향을 미치지 않는 것으로 나타났다. 또한, 가용성, 신뢰성, 경제성은 노력기대에 정(+)의 영향을 미치는 것으로 나타났다. 매개효과와 관련하여 노력기대는 스마트팜 기술적 특성인 가용성, 신뢰성, 경제성과 수용의도간의 관계를 매개하는 것으로 나타났다. 연구 결과는 스마트팜의 잠재적 수용자를 대상으로 한 정책수립의 방향성 모색, 실제 현장에서의 스마트팜 교육 및 컨설팅에서 활용할 수 있을 것으로 기대한다.

• Weed & Turfgrass Science
• /
• 제3권4호
• /
• pp.362-369
• /
• 2014

개량SCB저농도액비(DSCB)를 친환경적인 잔디관리에 이용하기 위하여 시비간격에 따른 켄터키블루그래스의 엽색지수, 엽록소지수, 잔디생육, 양분흡수 및 이용율을 바탕으로 DSCB의 적절한 시비방법을 평가하였다. 시험을 위한 처리구는 무처리(NF), 대조구(CF), 15일 간격으로 시비한 DSCB 처리구 (DSCB), 30일 간격으로 시비한 DSCB처리구(2DSCB), 4월부터 60일 간격으로 시비한 DSCB처리구(4DSCB-1), 그리고 5월부터 60일 간격으로 시비한 DSCB처리구(4DSCB-2)으로 구분하였다. 잔디의 엽색지수는 DSCB와 2DSCB가 CF보다 높았고, 엽록소지수는 CF와 비슷하였다. 질소와 칼리의 흡수량 및 이용율과 예지물량은 2DSCB와 4DSCB에서 CF보다 증가하였다. 이러한 결과들로 종합할 때, DSCB는 월 1회 시비하는 것이 잔디의 양분흡수와 이용을 증가시켜 잔디생육과 품질을 향상시키는 것으로 알 수 있었다.

• Journal of Animal Science and Technology
• /
• 제57권7호
• /
• pp.26.1-26.5
• /
• 2015

Background: Rice bran is a by-product of the rice-milling process, which remains largely underutilized; however, efficient processing treatments may improve its feeding value for chickens. This is of great economic and environmental importance, as this can lower the production costs, and offer an opportunity for valorization of a low-quality agricultural by-product, to a high-value feed source. Methods: This experiment was conducted to study the effect of extruded rice bran on performance and phosphorous (P) bioavailability in broiler chickens. In a completely randomized design, 200 seven-day-old broilers (Cobb 500) were allotted to five treatments with five replicates per treatment and 8 chicks per replicate, and fed with their respective diet during the starter (8 to 21 days) and grower (22 to 42 days) periods. Diets were a basal corn-soybean based diet (T1), or diets containing 20 % rice bran (T2), 30 % rice bran (T3), 20 % extruded rice bran (T4), or 30 % extruded rice bran (T5). Results: Birds feeding on T4 and T5 diets had a higher body weight gain and lower feed-to-gain ratio compared to those feeding on T2 and T3 diets (p < 0.05). Birds receiving diets containing extruded rice bran had higher total P availability and tibia ash content, as compared with those receiving diets containing un-extruded rice bran (p < 0.05). Relative weight of the pancreas was higher in birds receiving T2 and T3 diets. Conclusions: The results confirmed the beneficial effect of extrusion treatment of rice bran on performance and P availability in broilers. Up to 30 % extruded rice bran may be included in the broiler diet without apparent adverse effects on the performance.

• 한국토양비료학회지
• /
• 제49권5호
• /
• pp.510-516
• /
• 2016

Soil respiration has been recognized as a key factor of the change of organic matter and fertility due to the carbon and nitrogen mineralization. In this study, we evaluated the effect of soil respiration on the light fraction-C and inorganic N content depending on temperature in soil applied with organic matter. Soil respiration was calculated by using total $CO_2$ flux released from soil applied with $2Mg\;ha^{-1}$ of rice straw compost and rye for 8 weeks incubation at 15, 25, $35^{\circ}C$ under incubation test. After incubation test, light fraction and inorganic N content were investigated. Rye application dramatically increased soil respiration with increasing temperature. $Q_{10}$ value of rye application was 1.69, which was higher 27% than that of rice straw compost application. Light-C and $NO_3-N$ contents were negatively correlated to soil respiration. Light-C in rye application more decreased than that in rice straw compost with temperature levels. These results indicate that temperature sensitivity of soil respiration could affect soil organic mater content and N availability in soil due to carbon availability. Also, light fraction would be useful indicator to evaluate decomposition rate of organic matter in soil under a short-term test.

• 한국신뢰성학회지:신뢰성응용연구
• /
• 제16권3호
• /
• pp.192-201
• /
• 2016

Purpose: In this paper, we propose the output model of the optimal inventory requirements of the Maintenance Float (M/F). Weapon systems were modernized and increased costs. Thus, the complexity increases with. Alternatives to achieve the goal of availability of weapon systems and to reduce life-cycle cost are required. Especially, securing spare parts is more effective than adding the amount of equipment or maintenance facilities to achieve the goal of availability and reduce life cycle costs. However, securing spare parts and repair costs are directly related, so exact requirements are needed. Methods: Three kinds of methods (Calculation method of applying the Poisson distribution, Calculation method of considering the number of CSP, and Calculation method of applying M&S program) that this paper proposed compare the influence of the availability and the amount of spare parts. Result: We calculate the cost of M/F when the operational availability is over than 80% and compare that result. The biggest cost was calculated from the Poisson distribution method. We found that requirements and unit price is the key factor that gives a significant effect. Conclusion: These three kinds of methods can be used as a basis for Maintenance Float calculation. Among them, the calculation method based on CSP is optimal replacement equipment requirements calculation method.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
• /
• 제28권4호
• /
• pp.71-87
• /
• 2022

Purpose: This study examines the daylighting design factors of Korean dementia nursing homes, in order to realize a therapeutic environment based on the therapeutic effect of light in the rapidly aging trend with an huge increase in the population of dementia in Korea. Methods: Through literature reviews, this study aims to theoretically examine the therapeutic light environment for the elderly with dementia, derive daylighting design factors of Korean dementia nursing homes, and analyze their detailed design factors. Results: The result of this study can be summarized into two points. The first one is that the daylighting design factors reflected in dementia nursing homes are derived into six factors: building layout, windows, glazing, shading devices, spaces, and interior finishings that determine the availability of daylight. The second one is that the detailed daylighting design factors are shown as primary and secondary detailed design factors, and the main values to be considered when applying these factors into dementia nursing homes are analyzed as maximizing daylight availability, optimization of the possibility of therapeutic view, and anti-glare. Implications: The daylighting design factors will contribute to maximizing the availability of daylight, optimizing the possibility of view, and minimizing the glare in the living spaces of dementia nursing homes in Korea.

• Human Ecology Research
• /
• 제53권1호
• /
• pp.49-66
• /
• 2015

This study analyzes the effects of women's labour force participation and work-family reconciliation support on life-cycle fertility in Korea. The analysis is based on the longitudinal data from Korean Labour and Income Panel Study (KLIPS), which include the available information on life-cycle fertility and employment history. Employing a dynamic model of fertility, we estimated the life-cycle fertility of all the 15-49 years old women considered in this study by using a duration model. The major results of this study were as follows: First, women's labour force participation had a negative effect on the first birth, second birth, and all births (transition to births starting at different parities). Women's employment tended to lengthen the interval between births. Second, the availability of maternal leave had a positive effect on the first birth and all births for working women. Providing maternal leave to working women decreased the opportunity cost of childbearing and in turn, reduced the interbirth interval of women. However, the availability of parental leave had no significant effect on the births of working women. Third, the financial support for childcare had a positive effect on the first birth and all births. The economic support for childcare led to the reduction in the interbirth interval of women by increasing the probability of births. The use of a childcare center for the first child, which substitutes for the time that women needed to take care of their children, classified as time-intensive consumption goods, did not have any effect on the second birth. Fourth, the part-time employment of women had a positive effect on the second birth. A flexible working time schedule tended to decrease the interval between the first and the second births.