• Journal of environmental and Sanitary engineering
• /
• v.16 no.4
• /
• pp.38-46
• /
• 2001

The purposes of this study were to examine applicability of waste egg shells as conditioning agent, to determine the optimum conditions for improving digested sludge dewaterability and to compare with before and after adding them. It estimated that the optimum conditions were dosage 30 g/L, particle size 10mesh, temp. $30^{\circ}C$, pH 7 and dewatering pressure $2.66{\pm}10^4{\;}N/m^2$. On the basis of induced optimum conditions, if adding waste egg shells in digested sludge, its specific resistance was $1.13{\pm}10^{12}{\;}m/kg$ and was low about 3 times than raw digested sludge $3.5{\pm}10^{12}{\;}m/kg $. Therefore, in view of waste recycling, it seemed that we could utilize waste egg shells as conditioning assent for improving dewaterability of digested sludge.

• 한국생물공학회:학술대회논문집
• /
• 2003.10a
• /
• pp.289-293
• /
• 2003

Schizophyllum commune belongs to Basidiomycetes is able to produce an extracellular polysaccharide, beta-glucan, which has been well known as an effective immune stimulator. In other to obtain the optimum conditions for the polysaccharide production, Schizophyllum commune was cultivated in different cultivation media containing various carbon and nitrogen sources. For the cell growth and the polysaccharide production, the optimum synthetic medium was developed with YMP medium an a basal midium. The flask culture conditions for the polysaccharide production were $27^{\circ}C$ and 150rpm with the initial pH 5.5.

• Journal of the Korean Applied Science and Technology
• /
• v.17 no.2
• /
• pp.113-119
• /
• 2000

Alkylation of phenol with tert-butanol in the liquid phase on mordenite was studied. The influence of many reaction parameters such as calcination temperature, reaction temperature, t-butanol/phenol molar ratio on catalytic properties was discussed. The main products were 2,4-di-t-butylphenol, o-t-butylphenol, p-t-butylphenol, the last of these was wanted product. In order to enhance the selectivity of p-t-butylphenol, optimum conditions were recommended at $500^{\circ}C$ calcination temperature, $140^{\circ}C$ reaction temperature, 1.0 molar ratio of reactants over mordenite. P-t-butylphenol was formed with 90% isomer selectivity at optimum conditions after 4hr reaction. On the basis of the behavior obtained in the cases mentioned, optimum conditions and catalytic properties for t-butylation of phenol were provided.

• Journal of Industrial Technology
• /
• v.13
• /
• pp.3-17
• /
• 1993

The composting process is a suitable to dispose the livestock manure in terms of resources recovery. However the performence of composting process is greatly affected by the environmental conditions such as characteristics of manure, type of the bulking agent, initial moisture contents, temperature, recycle and so on. The purpose of this study is to evaluate the optimum environmental conditions of composting process for livestock manures. The analytical results indicated that no bulking agent was necessary for the cow manure because of the proper C/N ratio. However the pig manure required a bulking agent since the pig manure had not only low in C/N ration but poor ventilation characteristics. In addtion, the initial miosture content for optimum composting appeared to be about 60%. The temperature control was also an essential factor to enhance the activity of thermophilic microorganisms in the laboratory composting unit. It was further found that the recycle of composts may contributed the completion of composting precess as well as C/N ratio reduction and moisture control.

• Transactions of the Korean hydrogen and new energy society
• /
• v.26 no.1
• /
• pp.71-78
• /
• 2015

This study was performed to optimize the integrated thermal-alkali pre-treatment of flotation scum for the enhanced biodegradability. The optimum conditions of the integrated thermal-alkali pre-treatment were obtained using response surface methodology. The disintegration degree of carbohydrate (69.2%) and protein (57.3) were estimated under the optimum conditions. Although the optimum conditions were different, the disintegration degrees were similarly. A fermentative hydrogen batch test was conducted to evaluate the hydrogen production from scum with and/or without. The maximum hydrogen production from scum with pre-treatment was of 0.64 mol H2/mol hexoseadded, which about 1.4 times higher than without pre-treatment.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1997.04a
• /
• pp.8-13
• /
• 1997

In order to utilize the information of well-known grinding data or grinding machine, a database needs to be designed by considering the delicate property of the machine tools for the high precision and quality of the demanding specification. Among the machine tools, machining conditions of the grinding are various and knowledge repeatance obtained form the grinding process are less credable.Therefore it is desirable for D/B, which is used to set the grinding conditions, to utilize the maximum machine tool capability. The present paper studied occurance limit of chatter vibration and burn considering the characteristics of machine tool. And also basic experiments were performed to establish optimum grinding canditions which can maximize the machining efficiency.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.24 no.3 s.174
• /
• pp.752-760
• /
• 2000

Mechanical press joining has been used in sheet metal joining processes because of its simple process and possibility of joining dissimilar metals, such as steel and aluminum. The strength of mechanical press joining varies with joining conditions. The optimum joining conditions considering tensile-shear and peel-tension strength have to be established to assure the reliability in the joining strength. Therefore, optimization of joining conditions has been investigated for improving joining strength of sheet metal. It is possible to obtain optimum strength from improvement on the joining strength of peel-tension mechanical press joint under multiaxial stress states.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2008.05a
• /
• pp.321-324
• /
• 2008

This paper presents the battery management system(BMS) for the optimum conditions of the lead-Acid battery in UPS. The proposed system controls the over and under currents of battery for protecting and it was applied algorithm for optimum conditions to estimate the State Of Charge(SOC) in charge or discharge mode. It approved the performance and the algorithm for the estimation of SOC, through the experiments which using the charge and discharge tester and the field tests.

• Journal of Welding and Joining
• /
• v.12 no.3
• /
• pp.71-81
• /
• 1994

Laser cutting is experiencing a rising worldwide acceptance in the industry. Expert systems are necessary for the systematic arrangement and searching of experimental data existing in journal papers, job handbooks, etc.. This paper proposes an expert system for the selection of the appropriate laser cutting variables from the available database. Optimum cutting conditions according to the given cutting velocity were searched and qualitative comments which are difficult to be used as database variables were shown at each velocity using the binary and fuzzy inference. These comments could be informative to unskilled operators of the laser cutting process. Typical cutting conditions of the mild steel and stainless steel were included and the working range and quality variations were displayed graphically. The proposed algorithm was implemented in an IBM compatible personal computer as an expert system for CO$_{2}$ laser cutting to derive the optimum cutting conditions by using the turbo prolog.

• KSBB Journal
• /
• v.13 no.4
• /
• pp.364-368
• /
• 1998

The optimum conditions of the production of exo-polymer by Ganoderma lucidum WK-003 and it's hepatoprotective effect was studied. Optimum conditions for the production of exo-polymer (3.18 g/$\ell$) by using shaken flask culture of G. lucidum WK-003 were pH 4.5, 30$^{\circ}C$, 120 rpm for 18 days cultivation. Also exo-polymer productio (7.15 g/$\ell$) was optimized by 5$\ell$ jar fermenter cultivation with condition of pH 4.5, 30$^{\circ}C$, 200 rpm, 1.0 vvm for 6 days cultivation. Glutamic pyruvic transaminase(GPT) activities in serum of intoxicated Sprague-Dawley rat were decreased from 704 IU/L to 330 IU/L by oral administration of the exo-polymer (20mg/kg$.$day)f or 4 consecutive days.