• 환경위생공학
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• 제18권4호
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• pp.1-5
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• 2003

For studying out the method of the effective purification of waste waters such as dying, paper pulp and plating wastewater, we measured the COD removal efficiency, color and turbidity of those pollutants by the physical and chemical method using the Inorganic Coagulating Agent (CM, RM) and a High Voltage Generator. The COD removal efficiency measured when applying the Inorganic Coagulating Agent (CM, RM) was mush higher than that using the Existing Coagulating Agent In addition to, when using those two methods above mentioned at the same time, both the COD removal efficiency and the reduction-effect of the inserting quantities of Coagulating Agent were higher than those were used singly. The system using both an Inorganic Coagulating Agent and a High Voltage Generator will be useful in various fields of wastewater treatment.

• Journal of Advanced Marine Engineering and Technology
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• 제21권5호
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• pp.527-534
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• 1997

Freezing of an aqueous sodium cWoride solution (Nacl- H20) saturating a packed bed with ini¬tial salt concentrations of 5, 10, 15(k by weight is investigated experimentally in a rectangular cav¬ity. The system was cooled from the top, bottom and a vertical side wall. For the freezing experi¬ments from below, there was little effect of the initial salt concentration throughout the freezing process, and the global freezing rate was not affected by the initial salt concentration. For the freezing from above, the size of the mush region decreased and the mushlliquid interface became flatter as the initial liquid concentration is decreased. For the freezing from vertical side wall, reheating of the mixture was intensified with an increase in the initial salt concentration. For Ci= 5%, supercooling was observed only at the early times of freezing process, but for Ci= 15% small supercooling was observed throughout the freezing process.

• 한국식품영양학회지
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• 제8권4호
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• pp.275-279
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• 1995

A bacterium L-10 which produce mush of glutamic acid was Isolated from soil and identified as the genus Pserdomonas. The maximal glutamic acid production was obtained when the strain was cultured at 3$0^{\circ}C$ for 30 hrs in the optimal medium containing 5% glucose, 0.5% each of urea and yeast extract, 0.1% K2HP04, 0.02% MgSO4.7H20, 0.3% (NH, )rHP04, 0.5ug/l biotin and Initial pH 7.0, and then final glutamic acid production under the above conditions was 1.2mg/ml of cell cultures.

• 한국소음진동공학회논문집
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• 제19권5호
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• pp.447-453
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• 2009

Community noise has been great concerned in public. A traffic noise from a road or a railway has affected too mush damage on quiet living environment. In this paper, a measured noise signal on a street has been applied to extract a noise source and a path by using a complex cepstrum. An example shows that the waveform of the source and the path could be separated if a temporal windowing is properly applied.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 춘계학술대회논문집
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• pp.363-370
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• 2003

Shrinkage of injection molded parts is different form operational conditions of injection molding such as injection temperature, injection pressure and mold temperature, and mold design such as gate size. It is also various for different resins which have crystalline structure or not. In this study part shrinkage was investigated for various operational condition and resins; PBT for crystalline polymer, and PC and PMMA for amorphous polymer was used in experiment. Crystalline polymer shows higher part shrinkage by about three times than amorphous polymer. Part shrinkage increased as injection temperature and mold temperature increased and injection pressure decreased. Part shrinkage decreased as gate size increased since the pressure delivery is mush easier for large gate size. Part shrinkage according to the gate location was that the position in the part with close to the gate showed large shrinkage and this phenomenon might be occurred by residual stress.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1991년도 추계학술대회 논문집
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• pp.146-154
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• 1991

As the application of robotic systems expand its scope, more research efforts are given in providing mobility to the robotic systems so that they can travel across various paths including those with formidable obstacles such as stairways or rough terrains. Legged locomotion is mainly concerned because the walking motion, like that of animal behavior, has many advantages over wheel type or track type locomotion especially in rough terrain. Walking robot, in general, having a discrete number of legs, have inherently low static stability. Static stability can be increased to a certain degree, by improving walking method, but it has many limitations such as reduced travel speed. A very promising possibility lies in the use of balancing weight, nevertheless its actual implementation is very rare. In this study, a 4-legged walking machine is developed and the static stability margin is increased with the balancing weight. In the future, this robot will be used to take an experiment on the walking in mush terrain.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 추계학술대회 논문집 전력기술부문
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• pp.118-120
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• 2007

Today power system technology is being converged with communication system technology or information technology (IT). This conversion action affects on two parts vigorously so that IT has become very essential in power industry. But terminologies of two parts are confused and it is necessary that these are standardized to develop the industry mush more because the standardization is the first step of preparation to FTA environments.

• 조명전기설비학회논문지
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• 제14권3호
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• pp.1-5
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• 2000

본 논문은 양광주의 전계, 관벅온도, 관벽휘도를 측정하여 관의 형태에 따른 형광램프의 광학적, 전기적 특성 변화를 측정한 것이다. 각 램프의 전계 계산 결과, 그 지수들은 양광주부분에서 거의 변화되지 않았지만 음극 강하의 길이는 크게 변화하였으며, 관벽온도와 휘도는 음극부분에서 크게 변화되었다.

• Journal of Biosystems Engineering
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• 제23권4호
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• pp.335-342
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• 1998

The objectives of this study were to evaluate respiration characteristics and develop empirical respiratory rate equations for short gain rough rice. The carbon dioxide concentrations generated from mush rice at four level temperatures(10, 20, 30, 4$0^{\circ}C$) and 4 level moisture contents(17.2, 21.5, 25.9, 31.6％, d.b.) were measured by gas chromatography. The respiratory rates' increased exponentially with gain temperature and also with moisture content The relationship between respiratory rate and gain temperature fitted the Arrehenius' and Core's equations very well. Two empirical respiratory rate equations were presented as a function of gain temperature and moisture content. The values of determination coefficient for the developed respiratory rate equations were 0.999, and the result of t-test showed that there were no significant differences between predicted and measured respiratory rates on significance level of 1%. Therefore, it appeared that respiratory rates predicted by the respiratory rate equations agreed well with measured values. An equation for predicting dry matter losses of rough rice during storage was presented by modifying the respiratory rate equations based on chemical reaction of decomposition of carbohydrate.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.854-858
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• 2005

Methanol and water crude extracts, crude polysaccharides and crude polysaccharides-free of water crude extracts from Shiitake mush-room (Lentinus edodes) were investigated for their antioxidant capacity in total polyphenolics and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. Total polyphenolics in the crude polysaccharides-free of water crude extracts were higher than that of the other ones. And crude polysaccharides-free of water crude extracts and water crude extracts show high on DPPH free radical scavenging activity. Positive correlations were found between total polyphenolics and their antioxidant activity.