• Korean Journal of Microbiology
• /
• v.16 no.2
• /
• pp.71-78
• /
• 1978

Bacillus subtilis var. 816 was used for manufacturing fermented soybean which in turn is used as flavoring agent. Fermentation of soyebean or flat wheat was occasionally failed. It was elucidated that failure was due to the presence of bacteriophage. According to Hemphill and Whitely (1975), this bacteriphage might be belonged to the viulent phage group I as it is similar to SP82G, ${\phi}25$. In fact, the phenomena of the increase of moisture, disappenarance of mucin and existence of undersirable bacteria was attributed to the contamination of the above phage during the course of fermentation of soybean or flat wheat. Particularly disapparance of mucin was sufficiently correlated by the replication of the bacteriophage. The above phage can grow in the range of $30^{\circ}C\;to\;70^{\circ}C$. The optimum temperature was $40^{\circ}C{\sim}50^{\circ}C$. The optimum pH range was between pH 7.4 and pH 8.0. It is noticeable that staphylococci was replicating simultaneously with the phage. The head of 816 phage is hexagonal with a diameter of $10{\times}165{\sim}10{\times}240\;nm$. The end of the tail is enlaged. It has a size of 25 nm and this end areas are spreaded widely as fingers.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.57 no.9
• /
• pp.1546-1551
• /
• 2008

This paper is concerned with the problems of accurate losses segregation in capacitor-run single phase motor. Segregation of losses in single phase induction motor is more complicated than that in three phase induction motor, because of the backward magnetic field component in the motor. Generally there are two methods for losses segregation of single phase induction motor. The one is relatively complicated method based on parameter estimation of single phase induction motor. By the way, the other one is simplified method based on IEEE Standard 114. All of the methods for the experimental determination of single phase induction motor losses are studied in this paper. Since the IEEE Standard is not possible to be applied for all type of single phase induction motors, we modified that method to apply for losses segregation of capacitor-run single phase induction motor as unifying the method based on parameter estimation.

• Korean Chemical Engineering Research
• /
• v.48 no.6
• /
• pp.725-730
• /
• 2010

The fully thermally coupled distillation columns(FTCDC) are thermodynamically more efficient than conventional columns. Despite these advantages, industry has been reluctant to use FTCDC. This can be largely attributed to the lack of established design procedures and column operability. In this study, the $3{\times}3$control structure was applied to control the FTCDC which was simulated using Aspen HYSYS on the possible control structure of 4 kinds and control performance was investigated. As the result of dynamic simulations, one of the proposed structures had better controllability of product compositions and control efficiency was evaluated.

• Bulletin of the Korean Space Science Society
• /
• 2009.10a
• /
• pp.27.3-27.3
• /
• 2009

인공위성이 발사체로부터 분리되면, 인공위성은 가장 먼저 태양 전지판을 전개한 후 전력을 생산한다. 전력은 인공위성의 운영에 반드시 필요하므로, 태양전지판의 성공적인 전개는 인공위성의 성공적 임무 수행의 필수 요소이다. 따라서, 태양전지판 또는 태양전지판의 전개장치 개발시에는 태양전지판이 이상없이 전개되는지를 확인할 수 있는 태양전지판 전개해석을 반드시 필요로 한다. 현재 개발중인 저궤도 지구관측위성의 경우, 3장의 태양전지판이 사용이 되며, 각 태양전지판의 전개 및 고정은 힌지 및 스트럿으로 이루어진 태양전지판 전개장치에 의하여 이루어진다. 이 논문에서는 다물체 동역학 해석프로그램인 Recurdyn을 이용하여, 상세 태양전지판 전개해석을 수행하고자 한다. 이전 연구에서는 기본적인 전개해석 모델을 수립하여, 태양전지판의 기본 전개거동을 확인할 수 있었다. 그러나, 태양전지판이 완전히 전개된 이후에 고정되는 부분의 모델링이 복잡하여, 단순하게 가정하여 전개해석을 수행하였다. 이러한 가정은 태양전지판의 전개 입장에서는 좀 더 극한상황이 되었으며, 이러한 환경하에서도 충분히 태양전지판이 잘 전개됨을 확인할 수 있었다. 이 논문에서는 간략화된 태양전지판 고정장치 및 기타 다른 부분들을 좀 더 상세모델링 하여, 전개 거동이 좀 더 실제에 가깝도록 하였다.

• Journal of the Korean Applied Science and Technology
• /
• v.16 no.1
• /
• pp.95-103
• /
• 1999

In the separation of toluene/n-heptane mixture by the emulsion type liquid membrane in a batch system, the effect of surfactants on the separation factor and membrane stability were studied over the surfactant concentration ranging from 0.1 to 1.5 wt% at the contact time of 5 and 10 minutes and the settling time 5 and 10 minutes. The surfactants used were triethanol amine lauryl sulfate. The separation factor reached its maximum value at the surfactant concentration of 0.5 wt%. It was found that the percentage of membrane breakup reached its minium values and the separation factor showed its maximum value at the surfactant concentration of 0.5 wt%, which confirmed that efficient separation could be effect when emulsion liquid membrane were stable because of low membrane break up.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.12 no.3
• /
• pp.1-7
• /
• 1975

In this paper, a method of writing and reproducing high density data with ordinary Audio cassette deck is discribed. In writing, the data N or NRZ code are modulated into PM code to take the positive code N(1) and the negative code N(0) are taken from the complement of the NRZ code, each of which are written into 2 channel track. In reading, the error corrected and the clock pulse can be generated from the reading pulse itself. Also, without modifying the interior circuit of the deck it is possible to use the deck in both the data and audio by adapting a few simple circuits. Over the range of 25HZ-4KHZ, it was possible to write and reproduce at the speed of 787 bps transmission rate.

• Korean Journal of Microbiology
• /
• v.23 no.4
• /
• pp.309-314
• /
• 1985

Autoxotrophic mutants of a cellulolytic baterium Cellulomonas sp. CS 1-1 were grown at $30^{\circ}C$ for 6hr using a complete medium containing 0.5M sucrose and for another 90 min after addition of 0.3 U/ml penicillin G, and were protoplasted by 0.2mg/ml lysozyme for 2hr. Prototrophic recombinants were obtained at the rates of $10^{-3}$ to $10^{-5}$by fusing the protoplasts in the presence of 40% polyethyleneglycol3350. Nystatin could be used to eliminate fungal contamination during the regeneration of the plotaplasts.

• Journal of Radiation Industry
• /
• v.4 no.4
• /
• pp.319-323
• /
• 2010

Recently, Korean traditional raw rice wines (RRW) have received attention because they are a nutritious food with health properties. But the rapid deterioration of fermented RRW is one of the serious problems for brewing and marketing in the world beyond Korea. The goal of this study was to develop a way to enhance the quality and to lengthen the period of circulation of the RRW. A lactic acid bacterium was isolated from RRW. It was identified as Lactobacillus fermentum (98%) based on its biochemical properties, and 16S rRNA sequence. Treatments of RRW with gamma radiation and green tea extracts reduced the bacterial population except for yeasts and Lactobacillus in the RRW. This result suggested that the natural plant extracts and catechin products can be used as an effective natural storage agent.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.22 no.6
• /
• pp.134-141
• /
• 2018

In this paper, the possibility of using an MDF (Mild-detonating Fuse) as a linear separation device is studied. An MDF is a small diameter metal (lead) tube filled with explosives (RDX). Aluminum plate cutting experiments are carried out with different values of target plate thickness and explosives per unit length. Based on the experimental results, a numerical analysis method including the failure criteria is established. The mechanism and characteristics of using MDFs for aluminum plate cutting are identified; the possibility of using the current system as a linear separation device is verified. By utilizing a developed numerical method, the separation reliability for diverse structures and MDFs can be predicted in advance and the number of experiments required for development can be minimized.

• Journal of Internet Computing and Services
• /
• v.22 no.3
• /
• pp.37-43
• /
• 2021

In this paper, we study how objects from front and back cameras can be recognized in real time in a mobile environment to segment regions of object pixels and synthesize them through image processing. To this work, we applied DeepLabV3 machine learning model to dual cameras provided by Apple's iOS. We also propose methods using Core Image and Core Graphics libraries from Apple for image synthesis and postprocessing. Furthermore, we improved CPU usage than previous works and compared the throughput rates and results of Depth and DeepLabV3. Finally, We also developed a camera application using these two methods.