• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.1
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• pp.35-40
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• 2008

The environment of agriculture in Korea is changed very rapidly. Since the labours in fruit cultivation field are getting older, the resources and the aid materials for farming need to be multi functional and easy to use. Therefore, They have to use various kind of aid materials in field of fruit cultivation like as fruiting bag. The development of practical utilization way of embossing process for manufacturing of fruiting bag and wrapping paper of agricultural products was main purpose of this study. Embossing roll was designed in Ginyong Embo(Co.) for the embossing process of fruiting bag. The embossing treated fruiting bag was manufactured in Agro(Co.) at mill scale. The mechanical properties of embossing paper was investigated and operation efficiency of bagging was tested at field. The properties of embossed paper was satisfied for fruiting bags for cultivation of apple and pear.

• Korean Journal of Metals and Materials
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• v.47 no.4
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• pp.217-222
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• 2009

Cu as a tramp element has been reported to encourage transverse cracking upon straightening operation during continuous casting or mini-mill processing. Therefore, the hot workability of steels containing Cu should be investigated. The purpose of the present study was to examine the effect of Cu contents on the hot ductility of low carbon steels by using hot compression test. Hot compression test was carried out using a Gleeble. The specimens were heated to $1300^{\circ}C$ for solution treatment and then held for 300s before cooling at a rate of $1^{\circ}C/s$ to test temperatures in the range of $650{\sim}1150^{\circ}C$ ($50^{\circ}C$ intervals) with strain rate of $5{\times}10^{-3}/s$. In Cu containing steels, the hot ductility was decreased with increasing Cu content at high temperature region which is to be attributed to copper enriched phase formed at scale/steel interface, and low hot ductility with increasing Cu content at low temperature region is attributable to the strengthening of matrix by the formation of ${\varepsilon}-Cu$. The width of ductility trough region was decreased with increasing Cu content.

• Journal of Life Science
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• v.20 no.5
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• pp.662-669
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• 2010

Lipolytic enzyme-producing bacteria were isolated from edible oil mill effluents on tributyrin agar medium. The shake-flask-scale studies yielded a promising isolate and it was identified as Pseudomonas sp. An OME using various microbiological observations such as cultural, microscopic, and biochemical tests was undertaken and confirmed using PIBWIN bacterial identification software. Lipolytic enzyme production was screened with oils such as sunflower, caster, coconut, tributyrin, and olive. Amongst these, olive oil showed an increased lipase production 6.1 U/ml. In view of the highest lipolytic enzyme production with olive oil, further optimizations were carried out using olive oil as a carbon source. Lipolytic enzyme production was optimized by a conventional 'one variable at a time' approach and the significant factors were further analyzed statistically using response surface methodology (RSM). The effect of physical factors such as incubation time, temperature, initial medium pH, and nutritional factors such as concentration of olive oil and yeast extract were examined for lipase production. Lipolytic enzyme secretion was strongly affected by three variables (incubation time, concentration of yeast extract and olive oil). Therefore, the interaction of these three factors was further optimized using response surface methodology. The optimized conditions of lipase production using response surface methodology yielded a maximum of 9.62 U/ml with optimum conditions for incubation, yeast extract and olive oil concentrations were found to be 48 hr, 0.3 g. and 0.9 ml. respectively.

• Journal of Life Science
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• v.22 no.4
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• pp.472-477
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• 2012

A thermophilic $Alicyclobacillus$ $acidocaldarius$, which produces thermostable ${\alpha}$-amylase, was isolated from the hot water effluent of a boiled rice mill near Tirupati, Andhra Pradesh, India. The effect of different culture conditions on the growth and production of extracellular ${\alpha}$-amylase by thermophilic $A.$ $acidocaldarius$ was investigated in laboratory scale. The results showed that the optimum conditions for the production of ${\alpha}$-amylase are a temperature of $60^{\circ}C$, pH of 6.0, and medium starch concentration of 1.0%, and yeast extract and tryptone of 0.2%. Surfactants, like Tween-20 and SDS, up to 0.02%, were found to increase the bacterial growth and enzymes. Further increase in their concentration resulted in significantly decreased enzyme production.

• Journal of architectural history
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• v.8 no.4 s.21
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• pp.95-112
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• 1999

This Study starts from a recognition that the architecture is based on the process demanded by substantial needs as well as pure theoretical logic system. So this study aims at proposing another point of view differentiating process and principle of architecture from pure theoretical logic system in the creative process of the Governor's Palace by analyzing drawings in chronological order. Even though the Governor's Palace had not been built because of discord between authorities of India and Le Corbusier, it is undoubtedly one of the best proposals which contains very concepts and ideas of later Le Corbusier's architectural intentions. In the first design stage, overall conception of the building was carried out in the sketches and drawings till Jan, 1954 and in the second stage, the elaboration of the project was pursued till Mar. 1995. The scheme tends to begin too large and general in character, becoming tighter and more complex under pressure from the client and adjustments required by the design process itself. For example, scale reduction, division and development of internal circulation system and applying his early 'Five Points'. So new solutions are searched by oscillating between compromise modifications and radically different solutions in contracting the first ideas. From all these, it is concluded that the early doctrine (Five Points) are adjusted and extended towards another stage by the use of restricted pilotis, the concept of fenetre en longueur transformed into a sub stricture of facade, sustained concept of le plan libre, les toits jardins extended towards concept of the urban area. And these formal intentions of the Governor's Place has been carried through other contemporary projects like Mill Owner's Association in 1954 and Villa Shodan in 1952.

• Journal of the Korean Magnetics Society
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• v.12 no.2
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• pp.57-63
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• 2002

In order to increase the magnetic properties of a Nd-Fe-B sintered magnet, the general factors including particle size and its distribution, volume fraction of Nd$_2$Fe$_{14}$B phase, degree of alignment of Nd$_2$Fe$_{14}$B grain, oxygen content and grain size etc. should be optimized by controlling the composition of Nd-Fe-B alloy as well as the manufacturing process. In this study, fabrication of the Nd-Fe-B sintered magnet was carried out in a laboratory scale by controlling the composition of Nd-Fe-B alloy and the manufacturing process. The optimum milling condition was found by investigating the milling media, milling time and ball size. The addition of FeGa was effective to increase the coercivity of the Nd-Fe-B sintered magnet. A remanence of 14.4 kG, a coercivity of 9.4 kOe and a maximum energy product of 47 MGOe were obtained from the sintered magnet.

• Journal of Environmental Science International
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• v.19 no.4
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• pp.437-446
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• 2010

The pressure drop through pulse air jet-type bag filter is one of the most important factors on the operating cost of bagfilter houses. In this study, the pilot-scale pulse air jet-type bag filter with about 6 m2 filtration area was designed and tested for investigating the effects of the four operating conditions on the total pressure drop, using the coke dust collected from a steel mill factory. When the face velocity is higher than 2 m/min, it is not applicable to on-spot due to the increase of power expenses resulting from a high-pressure drop, and thus, 1.5 m/min is considered to be reasonable. The regression analysis results show that the degree of effects of independent parameters is a order of face velocity > concentration > time > pressure. The results of SPSS answer tree analysis also reveal that the operation time affects the pressure drop greatly in case of 1 m/min of face velocity, while the inlet concentration affects the pressure drop in case of face velocity more than 1.5 m/min.

• Resources Recycling
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• v.7 no.4
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• pp.64-75
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• 1998

The purpose of this study is to produce high putity composite powder composed of Fe-oxide, Mn-oxide and Mn-ferrite having superior homogencity in composition and particle size distribution by co-roasting process. Binary component metal (Fe, Mn) chloride solutions were produced by dissolving mill scale and ferro-mangancse alloy in hydrochloric acid. These chloride solutions contained the impurities such as SiO$_{2}$, P, Al, Ca and Na, which were originated from the Fe/Mn source materials. The neutralization and polymeric coagulant method were adoped to refine the hydrochloric liquor. When pH is far below the isoelectric point (pH 2-3), the SiO$_{2}$ was the most effectively reduced element, while other impurities remained unchanged. By increasing pH above 3, most of the impurities could be reduced effectively due to the coprecipitation reaction. The polymeric coagulants such as poly vinyl alcohol, resin amine and ammonium molybdate were found to have no effect on the spray roaster designed by the authors. The produced oxide powders were confirmed to be mixtures of Fe-oxide, Mn-oxide and mn-ferrite. the powders were homogeneously mixed and the particle size increased sleeply with increasing co-roasting temperature.

• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.1
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• pp.45-52
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• 2016

Blast furnaces are crucial equipment for steel production. A typical furnace risks unexpected accidents caused by contraction and expansion of the walls under an environment of high temperature and pressure. In this study, an acoustic emission (AE) monitoring system was tested for evaluating the large-scale structural health of a blast furnace. Based on the growth of shell cracks with the emission of high energy levels, severe damage can be detected by monitoring increases in the AE energy parameter. Using this monitoring system, steel mill operators can establish a maintenance period, in which actual shell cracks can be verified by cross-checking the UT. From this study, we expect that AE systems permit early fault detection for structural health monitoring by establishing evaluation criteria based on the severity of shell cracking.

• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.2
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• pp.19-29
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• 1994

A large volume of paper mill sludge(PMS) is produced every day from paper industries after treatments of waste water and it costs too much to dispose of the sludge. Since PMS consists mostly of biodegradable organic matter, cellulose, it is desirable to recycle it by proper treatments such as composting. In this study, experiments were conducted using a small scale reactor(12l) to establish optimum conditions for efficient composting of PMS of which initial pH, C/N ratio, and moisture content were 7.1, 28~30, and 60~65%, respectively. No heavy metals such as mercury, cadmimum, and lead were not detected in the PMS. Various levels of forced aeration, 1 minute aeration per every 30, 60, 120, 240, and 480 minutes were applied and 1 minute aeration per 60 and 120 minutes found to be proper for composting of 8l PMS in this system. Relationship between $CO_2$ production and temperatures was positively correlated with r> 0.82 suggesting that the normal decomposition of PMS by microorganisms occurred. However, under the condition of aeration interval over than 240 minutes, a negative relationship between two parameters was found indicating the occurrence of abnormal(maybe anaerobic) degradation. The amount of added nitrogen also affected composting of PMS resulting in the increase of $CO_2$ production and temperature. Semi-field tests using 100kg PMS in a static pile sysem showed that PMS could be composted efficiently under optimal environmental conditions. The parameters determining efficiency of composting such as C/N ratio, aeration, moisture content, and pH need to be monitored.