• Journal of Food Hygiene and Safety
• /
• v.15 no.1
• /
• pp.55-59
• /
• 2000

In order to develop a antimicrobial agent, dried bamboo trunk was extracted by high temperature suction and then antimicrobial activities against Staphylococcus aureus ATCC 2825 and Escherichia coli DH 5$\alpha$ were investigated as compared with tea tree oil and BHA. The minimal inhibitory concentrationo(MIC) of the extracted substance against microorganisms were also examined. The results are as follows: 1. By disc diffusion method, BHA showed the strongest antimicrobial activity on Gram-positive bacteria such as S. aureus ATCC 2825 but bamboo essential oil showed the strongest antimicrobial activity on Gram-negative bacteria such as E. coli DH 5$\alpha$. 2. By broth dilution method, the minimum inhibitory concentration of the BHA, tea tree oil and bamboo oil were not detected against S. aureus ATCC 2825(MIC, 6.0 $\mu$l/ ml) and E. coli DH 5$\alpha$(MIC, 6.0 $\mu$l/ ml)

• Food Science and Biotechnology
• /
• v.14 no.4
• /
• pp.450-455
• /
• 2005

This study was conducted to determine firstly the composition of the essential oil from fresh changpo (Acorus calamus var. angustatus Bess) roots quantitatively and qualitatively by use of two internal standards, and secondly volatile compounds which are primarily responsible for the aroma of changpo roots. Simultaneous steam distillation and extraction method was used for essential oil extraction, and aroma extract dilution analysis (AEDA) and sniffing test by gas chromatography/olfactometry (GC/O) were used to detect the characteristic impact odorants. According to the instrumental analysis of changpo root essential oil, cis, trans-famesol (47.56 mg/kg of fresh wt), octanoic acid (23.73 mg/kg of fresh wt), trans-2-dodecenal (20.28 mg/kg of fresh wt) and trans, trans-farnesol (13.81 mg/kg of fresh wt) were the most abundant compounds. Geranyl acetate, trans-nerolidol and trans, trans-farnesyl acetate were evaluated as the characteristic impact odorants of changpo roots from results of AEDA and sniffing test. Especially, geranyl acetate was considered as the most similar odor component to changpo roots by organoleptic evaluation with GC/O.

• Proceedings of the KSAR Conference
• /
• 2004.06a
• /
• pp.201-201
• /
• 2004

In this study we examined whether vitrified Hanwoo (Korean cattle) IVM/IVF/IVC blastocysts can survive in vitro/in vivo by a quick one-step dilution method and these embryos result in live births. Blastocysts produced in vitro were vitrified by serial exposure to glycerol (G) and/or ethylene glycol (EG) mixtures of 10% (v/v) G for 5 min, 10% G plus 20% EG (v/v) for 5 min, and 25% G plus 25% EG (v/v) for 30 see. (omitted)

• Journal of Electrical Engineering and Technology
• /
• v.11 no.2
• /
• pp.537-542
• /
• 2016

The demand for LBS (Location Based Services) is increasing in the development of communication and mobile technologies. Positioning technology is a core technology for LBS, because LBS is based on a position of each device or user. But positioning technology especially for indoor environments is getting a lot of attention. Indoor positioning errors usually occur seriously in indoor environments where APs (Access Points) are set in a very concentrated and complex arrangement. In order to reduce indoor positioning errors, we adopt DOP (Dilution of Precision) which reflects an APs configuration information. In this paper, we propose an enhanced indoor positioning method using IEEE 802.11 RSSI measurements and AP configuration information.

• 한국연소학회:학술대회논문집
• /
• 2012.11a
• /
• pp.59-60
• /
• 2012

This paper describes gas turbine combustion characteristics of synthetic gas which is mainly composed of hydrogen and carbon monoxide. The combustion characteristics such as combustion instability, NOx and CO emission, temperatures at turbine inlet, liner and dump plane, and flame structure were investigated when changing when changing $H_2:CO$ ratio, dilution ratio, and $CH_4:syngas$ ratio. From the results, quantitative relationships are derived between key aspects of combustion performance, notably NOx emission. It is concluded that NOx emission of syngas is strongly influenced by the diluent heat capacity and combustion instability. Moreover, NOx control method using diluents such as $N_2$, $CO_2$, steam is verified.

• Korean Journal of Veterinary Service
• /
• v.21 no.2
• /
• pp.107-115
• /
• 1998

In order to establish a rapid, sensitive and specific diagnostic method for detection of antibody to Brucella abortus, a enzyme-linked immunosorbent assay(ELISA) was adapted. The diagnostic efficacy of the established ELISA was compared with that of the standard tube agglutination test for B abortus. 1. It was found that the optimal concentration of antigen for this ELISA was 5$\mu\textrm{g}$/ml, the optimal dilution of conjugate was 1 : 2000, and the optimal dilution of serum was 1 : 200, respectively. 2. Cut off value in this ELISA was 1,102 that was determined by mean absorbance(at 492nm) of tube agglutination test negative serum added with the triple value of the standared devation. 3. The relationship between the tube agglutination test and ELISA was showen high corresponding rate with sensitivity(96.3%) and specificity(98.1%). 4. The efficacy of the ELISA for detection of B abortus antibody was compared with tube agglutination test In brucellosis outbreak farm. The sensivity of ELSIA was higher than tube agglutination test.

• Proceedings of the KSME Conference
• /
• 2003.11a
• /
• pp.332-337
• /
• 2003

Oxygen-enriched non-premixed flame characteristics was investigated numerically with variation of dilution methods, which are Flue gas recirculation(FGR) and fuel injection recirculation(FIR). In order to compare flamelets in various oxygen-enrichment conditions reasonably, the adiabatic flame temperature and Damkoller number was held fixed by modulating amount of diluents to fuel and oxidizer stream and by varying global strain rate of flame respectively. Also modified GRI 3.0 reaction mechanism was utilized, which was able to predict oxygen-enriched methane flame correctly. Fundamental flame characteristics such as structure, heat release rate and extinction with FGR and FIR were compared in various oxygen enrichment conditions.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.9 no.11
• /
• pp.4453-4468
• /
• 2015

This paper investigates optimization-based base station (BS) placement. An optimization model is defined and the BS placement problem is transformed to a lexicographical stratified programming (LSP) model for a given trajectory, according to different accuracy requirements. The feasible region for BS deployment is obtained from the positioning system requirement, which is also solved with signal coverage problem in BS placement. The LSP mathematical model is formulated with the average geometric dilution of precision (GDOP) as the criterion. To achieve an optimization solution, a tolerant factor based complete stratified series approach and grid searching method are utilized to obtain the possible optimal BS placement. Because of the LSP model utilization, the proposed algorithm has wider application scenarios with different accuracy requirements over different trajectory segments. Simulation results demonstrate that the proposed algorithm has better BS placement result than existing approaches for a given trajectory.

• Bulletin of the Korean Chemical Society
• /
• v.14 no.6
• /
• pp.696-700
• /
• 1993

Gold bonding wire of 0.076 mm in diameter used in semiconductor industry, is dissoved in aqua regia. The solution is then evaporated to near dryness several times with a few drops of HCl added to prepare the final sample solution in 5% HCl. The gold matrix is separated from trace impurities by controlled potential deposition. The whole electrolysis has been carried out inside a clean bench. An optimum potential is found to be +0.25 V to give more than 99.9% Au matrix removal with better than 90 analytes remaining in the electrolyte solution. Isotope dilution calibration is employed to get the best accuracy and precision. Analytical results are presented with determination limits of the analytical method.

• Nuclear Engineering and Technology
• /
• v.52 no.12
• /
• pp.2867-2873
• /
• 2020

In reprocessed uranium, derived from an impoverished fuel of light-water moderated reactors, there are isotopes of ^{232, 234, 236}U, which make its recycling remarkably difficult. A method of concentration of ²³⁵U target isotope in cascade's additional product was proposed to recover the isotopic composition of reprocessed uranium. A general calculation procedure is presented and a parameters' optimization of multi-flow cascades with additional products. For the first time a numeric model of a cascade that uses the cuts of partial flows of stages with relatively high separation factors was applied in this procedure. A novel computing experiment is carried out on separation of reprocessed uranium hexafluoride with providing a high concentration of ²³⁵U in cascade's additional product with subsequent dilution. The parameters of cascades' stages are determined so as to allow reducing the ^{232, 234, 236}U isotope content up to the acceptable. It was demonstrated that the dilution of selected products by the natural waste makes it possible to receive a low enriched uranium hexafluoride that meets the ASTM C996-15 specification for commercial grade.