• Ecology and Resilient Infrastructure
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• v.7 no.2
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• pp.134-144
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• 2020

In-situ stabilization is a remediation method using amendments to reduce contaminant availability in contaminated soil. We tested the effects of two amendments (furnace slag and red mud) on the availability of toxic trace elements (TTEs) and soil enzyme activities (dehydrogenase, phosphatase, and urease). The application of amendments significantly decreased the availability of TTEs in soil (p < 0.05). The decreased availability of TTE content in soils was accompanied by increased soil enzyme activities. We found significant negative relationships between the TTE content assessed using Ca(NO₃)_2^-, TCLP, and PBET extraction methods and soil enzyme activities (p < 0.01). Soil enzyme activities responded sensitively to changes in the soil environment (pH, EC, and availability of TTEs). It could be concluded that soil enzyme activities could be used as bioindicators or ecological indicators for soil quality and health in environmental soil monitoring owing to their high sensitivity to changes in soil.

• Proceedings of the Korean Reliability Society Conference
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• 2001.06a
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• pp.301-310
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• 2001

Lim et al.(1998) proposed the Bayesian Imperfect Repair Model, in which a failed system is perfectly repaired with probability P and is minimally repaired with probability 1 - P, where P is not fixed but a random variable with a prior distribution II(p). In this note, the steady state availability of the model is derived and the measure is obtained for several particular prior distribution functions.

• Journal of the Korea Institute of Military Science and Technology
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• v.22 no.3
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• pp.416-424
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• 2019

This paper studies the optimal inventory levels of P-3 assemblies in order to assure the required operational availability. A simulation model is developed for identifying the impact of the inventory levels on operational availability. Based on the result of the simulation model, multiple regression analysis is performed. Finally, the optimal inventory levels of critical P-3 assemblies are determined with integer programming. Additionally, sensitivity analysis of depot maintenance period is also conducted for its impact on the operational availability.

• Korean Journal of Environmental Agriculture
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• v.23 no.2
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• pp.104-110
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• 2004

Although silicon (Si) has been Down to be an essential element fer rice growth, the optimum soil level of Si for upland crops remains unestablished. This study was conducted to estimate the availability of Si fertilizer in upland soils, and also effect of the Si fertilizer on soil pH was examined. Different application rates of Si fertilizer were tested using faur soils of different available Si levels and pHs in a series of laboratory incubation study. The treatments included Si fertilizer levels of 100, 200, and 300 kg/10a. Also to examine the effects of compost and lime on the availability of Si fertilizer in upland soil, treatment of silicate fertilizer 200 kg/10a + compost 1,000 kg/10a and lime alone treatment were included. Changes of Si availability in the soils during the incubation period were measured by 1 N NaOAc extraction procedure. Availability of Si fertilizer was different among the tested soils, and about $9.1{\sim}19.2%$ of the applied Si fertilizer was extracted after 60 days laboratory incubation. Application rate could not influence the availability of Si fertilizer. Application of compost with Si fertilizer could not increase Si availability in upland soils, but lime treatment could increase Si availability. Soil pH increased by application of Si fertilizer, but the effect of Si fertilizer on soil pH was minimal. When Si fertilizer is applied on the purpose of Si nutrition in acid upland soils, lime treatment should be coupled with the Si fertilizer for remediation of soil acidity.

• Korean Journal of Environmental Agriculture
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• v.26 no.4
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• pp.286-296
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• 2007

To increase phosphate (P) availability in soils, the efficiency of silicate (Si) in reducing P adsorption was investigated by competitive adsorption tests under changing conditions of pH, ion concentrations, and order of anion addition along with single adsorption properties of each ion at $20^{\circ}C$. In the single ion adsorption study, P and Si ions showed the opposite reaction patterns: phosphate adsorption decreased with increasing pH and attained adsorption maximum however, silicate adsorption increased with increasing pH without attaining adsorption maximum. Phosphorus and Si adsorption were influenced by pH in the range of 5.0 - 9.0 and the type and amount of P and Si concentration. Silicate added to soil before P or in a mixture with P significantly reduced P adsorption above pH 7.0; however, there was no significant Si-induced decreased in P adsorption at pH 5.0 when anions were added as mixture. The efficiency of Si in reducing P adsorption increased with increasing Si concentration and pH. The effect of P on Si adsorption was relatively small at pH 5.0 and no effect of P on silicate adsorption was observed at pH 9.0. The presence of Si strongly depressed P adsorption when Si was added before P compared to P and Si added as a mixture. These results suggest that application of Si may decrease P adsorption and increase the availability of P in soils. Furthermore, a Si source would be better to add before P application to enhance the availability of P in soils.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.4
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• pp.813-818
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• 2015

In this paper, WiMedia Distributed-MAC protocol is adopted for development of a seamless N-screen wireless service. Furthermore, to provide the OSMU (One Source Multi Use) N-screen service through P2P streaming in the seamless D-MAC protocol, a new Multicast-free DRP Availability IE is proposed and analyzed. In this Multicast-free DRP Availability IE, indicating Multicast DRP Owner and Receiver is required. The ACK frame transmissions are not required for Multicast transmissions in P2P N-screen services. Using this property, the Multicast-free DRP Availability IE scheme is proposed to expand the number of time slots available for unicast and multicast DRP reservations. Simulation results show that our Multicast scheme enhances performances in vewpoints of DRP reservation conflict and throughput.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.6
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• pp.793-799
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• 2002

Four feeds, three concentrates (rice bran, soybean meal and flaked corn) and one forage (corn silage) were incubated in four ruminally fistulated Holstein steers over three one week periods in a 3${\times}$4 incomplete latin square design where steers served as blocks and feeds as treatment. The objectives of the study were to investigate in situ DM, N and P degradability characteristics of feeds in order to assess availability of these nutrients by ruminants. In each period, all feeds were incubated in quadruplets (corn silage in triplicates) in the rumen of each steer in a reverse order for 3, 6, 9, 12, 18, 24 and 48 h. The DM 'a' fraction was higher and lower (p<0.001) in corn silage and rice bran respectively. Although corn silage contained the lowest (p<0.01) DM 'b' fraction, flaked corn contained the highest. Rate of DM degradation of flaked corn and corn silage were half (p<0.05) of the rate of DM degradation of either rice bran or soybean meal. Potential or effective DM degradability (p<0.05 to 0.001) at various passage rates were the lowest for rice bran and the highest for soybean meal. Corn silage N 'a' and 'b' was the highest and lowest, respectively (p<0.01). N 'c' of corn silage and rice bran was higher (p<0.001) than other feeds. Potential N degradability was the lowest in flaked corn (p<0.05). P 'a' was high (p<0.01) for corn silage and rice bran. P 'b' fraction was very high (p<0.001) in soybean meal but was absent in corn silage. Availability of DM (p<0.01 or 0.001), N (p<0.001) and P (p<0.05) differed between feeds at various passage rates except P availability at k=0.02 per h (p>0.05). The results demonstrate that the availability of DM, N and P by ruminants depends on feed as well as categories of animal.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.11a
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• pp.437-440
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• 2003

본 논문은 P2P 네트워크에서 어플리케이션 레벨의 영속성있는 저장 시스템에 대해서 살펴본다. 인터넷 클라이언트의 성능 향상과 인터넷 접속 기술의 발달로 Peer-to-Peer (P2P)라는 키워드로 대표되는 다양한 파일 저장, 검색, 공유 어플리케이션이 소개되었다. 그러나, 기존의 서버 기반의 분산 저장 방식은 xDSL 기반의 가변 IP 기반의 현재 인터넷 환경에서 불안정한 성능을 보이고, 파일을 저장하고 나서 검색 발견의 확률이 떨어지는 문제점을 가진다. 본 논문에서는 시스템의 가용성(Availability)을 높이기 위한 파일의 분할 저장, 중복 저장 방법을 소개하고 이의 효과를 분석해 보인다.

• Mycobiology
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• v.33 no.1
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• pp.35-40
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• 2005

Selected isolates of Pseudomonas fluorescens (Pf4-92 and PfRsC5) and P. aeruginosa (PaRsG18 and PaRsG27) were examined for growth promotion and induced systemic resistance against Fusarium wilt of chickpea. Significant increase in plant height was observed in Pseudomonas treated plants. However, plant growth was inhibited when isolates of Pseudomonas were used in combination with Fusarium oxysporum f. sp. ciceri (FocRs1). It was also observed that the Pseudomonas spp. was colonized in root of chickpea and significantly suppressed the disease in greenhouse condition. Rock wool bioassay technique was used to study the effect of iron availability on the induction of systemic resistance to Fusarium wilt of chickpea mediated by the Pseudomonas spp. All the isolates of Pseudomonas spp. showed greater disease control in the induced systemic resistance (ISR) bioassay when iron availability in the nutrient solution was low. High performance liquid chromatography (HPLC) analysis indicated that an the bacterial isolates produced more salicylic acid (SA) at low iron ($10\;{\mu}M$ EDDHA) than high iron availability ($10\;{\mu}Fe^{3+}$ EDDHA). Except PaRsG27, all the three isolates produced more pseudobactin at low iron than high iron availability.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.6
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• pp.551-566
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• 1997

Phosphorus has been known as an essential component of animal body. However, the requirement has not been determined precisely because of the variable bioavailabilities of feedstuffs from plant origin. The bioavailability of P in various feedstuffs of plant origin varies from 10 to 60%. Digestibility and availability of the P differed considerably depending on the feed. The lowest values were found for maize (under 20%), the highest for wheat and triticale (over 50%). This is due to the proportion of phytate and the presence of intrinsic phytase. And the digestive tract of monogastric animals does not contain sufficient amounts of phytase, an enzyme that hydrolyses the unavailable phytate complexes to available, inorganic orthophosphates. Microbial phytase supplementation improves the P availability, and both intrinsic plant and microbial phytase improves the availability of P in feedstuffs of plant origin. In a mixture of feeds with low and high activity of intrinsic phytase and/or supplemented by commercial phytase, the P availability is additive. However, in the light of current results it seems that exceeding the P availability equal to 60-70% is unrealizable even at large microbial phytase doses.