EPS용 SPMSM의 회전자 형상에 따른 효율 및 열 특성 개선 설계

차창준(Chang-Jun Cha),박진철(Jin-Cheol Park),박민로(Min-Ro Park),박현진(Hyeon-Jin Park),홍정표(Jung-Pyo Hong) 한국자동차공학회 2019 한국자동차공학회 부문종합 학술대회 Vol.2019 No.5

Electrical Power Steering(EPS) system that assist driver’s vehicle steering is one of the core parts of the vehicle. In addition, the EPS motors require very low vibration and high performance for vehicle stability. In this paper, the electrical parameters of EPS motor is converted into the function of the rotor shape. Using this function, the efficiency and thermal characteristics of the EPS motor are analyzed according to the rotor shape. Then, the design point with high efficiency and improved thermal characteristics is determined as the sizing effect. Then, the improved model is designed. Finally the validity of the improvement model is confirmed by comparing the efficiency and thermal characteristics of the improved model with the existing model.

분할 코어를 적용한 EPS용 SPMSM의 공차에 따른 코깅 토크 분석

차창준(Chang-Jun Cha),박진철(Jin-Cheol Park),박민로(Min-Ro Park),임명섭(Myung-Seop Lim),이충성(Choong-Sung Lee) 한국자동차공학회 2019 한국자동차공학회 학술대회 및 전시회 Vol.2019 No.11

The Electric Power Steering(EPS) system is directly related to safety. So, the whole system is mechanically connected. Due to mechanical characteristics of the steering system, vibrations generated by the EPS motor are transmitted to the driver. Cogging torque is generated by the interaction between the permanent magnet and the slot structure. Cogging torque is one of the torque ripple components. This paper investigates the cogging torque according to manufacturing tolerance of SPMSM with Segmented-Core for EPS. First, manufacturing tolerances for each part of the motor will be introduced. Then, the harmonics of the cogging torque due to each manufacturing tolerance of the motor part are analyzed. Finally, by comparing the simulation result with test value, the validity of this study is demonstrated.

분할코어를 적용한 EPS용 SPMSM의 극, 슬롯 수에 따른 조립공차에 의한 코깅토크 분석

차창준(Chang-Jun Cha),박진철(Jin-Cheol Park),김동민(Dong-Min Kim),박민로(Min-Ro Park),임명섭(Myung-Seop Lim) 한국자동차공학회 2020 한국자동차공학회 부문종합 학술대회 Vol.2020 No.7

As interest in the environment increase, the automobile parts market is increasingly trying to change from the mechanical system to the electrical system. In order to replace the mechanical system with the electrical system, many studies have been conducted to improve the performance of the electrical system because the electrical system must perform better than the mechanical system. However, there are few studies on tolerances that occur during actual production compared to studies on improving electrical performance. Due to the tolerances that occur during production, products with lower performance than actually expected can be produced. This paper intends to confirm the change in motor cogging torque due to the stator inner diameter tolerance applied to the segmented core, which is frequently applied to motors.

Ginsenoside 전환이 가능한 인삼 발효 미생물의 선별

김희규,김기연,차창준,Kim, Hee-Gyu,Kim, Ki-Yeon,Cha, Chang-Jun 한국미생물학회 2007 미생물학회지 Vol.43 No.2

오래전부터 약재로서 이용되어온 인삼(Panax ginseng)은 그 효능이 과학적으로 밝혀지면서 세계적으로 관심의 대상이 되고 있다. 그러나, 서양삼에 비해 점차 뒤처지고 있는 우리나라의 인삼산업의 경쟁력 확보를 위해 기능성 식품으로서의 인삼개발이 필요한 실정이다. 발효인삼은 유용한 미생물을 probiotic으로서 공급할 수 있을 뿐 아니라, 미생물에 의해 인삼의 ginsenoside 성분이 특이적으로 전환되어 기능적으로 우수한 제품이 될 수 있다. 본 연구에서는 인삼분말만을 영양분으로 한 액체 배지에서 청국장에서 분리된 Bacillus 균주와 유산균의 생장능 및 인삼의 주요 ginsenoside의 전환능력을 알아보았다. 인삼 2.5% (w/v), 1% (w/v)의 인삼분말만을 영양분으로 한 액체배지에서 생장능과 발효 후 ginsenoside의 전환 여부를 확인하였다. 사용한 Bacillus 균주와 유산균 모두 인삼배지에서 $10^{7}\;CFU/ml$을 초과하는 생장능을 보였고, Bacillmus의 경우 ginsenoside $Rg_{1},\;Rb_{1},\;Rb_{2},\;Rc,\;Rd$간에 각 균주마다 특이적인 ginsenoside 전환 반응을 보였다. 따라서, 이 균주들은 발효인삼의 제조를 위한 접종균주로서 이용이 가능하리라 사료된다. Panax ginseng has been drawing world-wide attention since it was used for medicinal purposes and its effects was discovered in scientific manners. However, it is necessary to develope new ginseng products as functional foods to compete with western ginseng. Fermented ginseng could be an excellent solution, where useful probiotics are provided and ginsenosides are specifically transformed to functional forms. In this study, we investigated the growth and ginsenoside biotransformation by 21 Bacillus strains isolated from Chongkukjang and 12 lactic acid bacteria. 2.5% (w/v) and 1% (w/v) of ginseng were used in culture media containing only ginseng powder as a sole nutrient source, and their biotransformation abilities were tested after the growths were checked. All used Bacillus strains and lactic acid bacteria were able to grow well in ginseng powder media at higher levels than $10^{7}\;CFU/ml$. Most of Bacillus strains displayed ginsenoside transformation in a strain-specific manner. Therefore, the results of this study demonstrated that the strains tested in this study could be used as potential starters for the ginseng fermentation.

하수처리장 방류수에 존재하는 항생제 내성인자가 하천에 미치는 영향

장예진,유용재,설우준,차창준,이옥재,채종찬,Jang, Yejin,Yoo, Yong-Jae,Sul, Woo Jun,Cha, Chang-Jun,Rhee, Ok-Jae,Chae, Jong-Chan 한국미생물학회 2017 미생물학회지 Vol.53 No.4

하수처리장 방류수와 하천 중의 항생제 내성인자 분포에 대한 상관성을 분석하기 위해 방류수와 상류 하천수, 하류 하천수를 대상으로 항생제 내성유전자와 전파 관련 유전자를 조사하였다. 3개 지점에서 134~183개의 항생제 내성유전자(ARG) 및 전파 관련 유전자(MGE)가 검출되었으며, 1개의 16S rRNA 유전자에 대한 ARG 및 MGE 유전자의 상대적인 총 합이 0.063~0.422 copy로 분석되었다. ARG와 MGE의 수와 존재량은 방류수에서 가장 높게 검출된 반면, 총 세균 수는 가장 적게 검출됨으로서 하수처리 과정에서 사멸된 세균에 포함된 유전자들이 검출된 것으로 판단된다. 또한 MGE의 존재량 양상이 ARG의 존재량과 상관관계를 보임으로서 항생제 내성균들의 내성기작이 자연내성보다는 획득내성일 가능성을 제시하였다. The antibiotic resistant genes (ARG) and mobile genetic elements (MGE) were investigated with the effluent of waste-water treatment plant (WWTP), and river waters of upstream and downstream in order to elucidate the effect of effluent on antibiotic resistance in a natural river. Total numbers of 134~183 of ARG and MGE were detected and the abundance of ARG and MGE was 0.063~0.422 copies per one of 16S rRNA gene in three water samples. Effluent sample contained the highest amount of the total number and abundance of ARG and MGE whereas total viable cells were observed in the lowest amount among the three samples. This indicated that the genes were originated from cells died during the wastewater treatment process. In addition, the co-relationship of abundance between ARG and MGE suggested that acquired resistance was a prevalent mechanism among the antibiotic-resistant bacteria existing in WWTP.

갈색부후균의 효소시스템을 이용한 목질계 바이오매스의 효소당화

윤정준(Yoon, Jeong-Jun),차창준(Cha, Chang-Jun),김영숙(Kim, Yeong-Suk),김영균(Kim, Young-Kyoon) 한국신재생에너지학회 2006 한국신재생에너지학회 학술대회논문집 Vol.2006 No.11

Recently the production of ethanol from lignocecllulosics has received much attention due to immense potential for conversion of renewable biometerials into biofuels and chemicals. Fomitopsis palustris causes a typycal brown-rot and is unusual in that it rapidly depolymerize the cellulose in wood without removing the surrounding lignin that normally prevents microbial attack. This study demonstrated that the brown rot basidiomycete F. palustris was able to degrade crystalline cellulose. This fungus could also produce the three major cellulases (BGL, EXG and EG) when the cells were grown on 2.0% Avicel. The fungus was able to degrade both the crystalline and amorphous forms of cellulose from woody biomasses. Moreover, we found that this fungus has the processive EG like CBH which are able to degrade the crystalline region of cellulose. To establish the cellulase system in relation with degradation of woody biomass, we performed that purification, characterization and molecular cloning of a BGL, EGs and GLA from F. palustris grown on Avicel.

일체형 코어와 분할코어 적용에 따른 SPMSM의 제작공차를 고려한 전기적 특성 비교 분석

조윤성(Yun-Sung Jo),차창준(Chang-Jun Cha),박진철(Jin-Chul Park),박민로(Min-Ro Park),임명섭(Myung-Seop Lim) 대한전기학회 2019 대한전기학회 학술대회 논문집 Vol.2019 No.10

분할코어를 적용한 EPS용 SPMSM의 설계변수에 따른 조립공차에 의한 코깅토크 분석

고욱(Gu Xu),차창준(Chang-Jun Cha),박진철(Jin-Cheol Park),김동민(Dong-Min Kim),임명섭(Myung-Seop Lim) 한국자동차공학회 2020 한국자동차공학회 부문종합 학술대회 Vol.2020 No.7

The EPS system is a driving aid that can improve the steering performance of the vehicle and reduce the driver’s burden of steering. However, because the EPS system is driven by a motor, it must be affected by the cogging torque generated from the motor. Moreover, when the assembly tolerances occur, the magnitude of the cogging torque will directly affect the steering performance of the vehicle. Therefore, in order to improve the cogging torque, factors affecting the cogging torque should be identified. In this paper, according to assembly tolerance, a 12pole-18slot motor is selected to analyze the factors affecting the cogging torque. Firstly, select the design parameters around the air gap. Secondly, determine the range of Slot-opening, Tooth-tip and PM thick which are the design variable of the motor. Finally, determine the tendency of the magnitude of torque and harmonic order of torque to vary with the design variable.

Amylase와 Protease의 활성이 높은 현미 발효 미생물의 선별

김기연,김희규,송병철,차창준,Kim Ki-Yeon,Kim Hee-Gyu,Song Byeong-Chul,Cha Chang-Jun 한국미생물학회 2006 미생물학회지 Vol.42 No.2

현미는 백미에 비하여 식품영양학적 가치 및 식이섬유의 함유량이 높은 쌀겨 및 배아를 포함하고 있으나 소화가 잘되지 않는 단점 이 있다. 따라서 발효현미는 소화력을 높임과 동시에 좋은 영양 공급원이 될 수 있으므로 높은 amylase와 pretense의 활성으로 현미를 발효할 수 있는 미생물을 선별하였다. 2.5%(w/v)의 현미분말을 유일한 영양원으로 한 액체배지를 생장배지로 사용하여 생장능력과 효소 생산능력을 조사하였다. 조사한 8종의 Bacillus 와 11종의 유산균 중에서 모든 Bacillus 균주와 두 종의 유산균이 생장과 효소활성을 보였다. 생균수는 $10^7CFU/mL$을 초과하였으며 Bacillus sp. Bacillus sp. B2, Bacillus sp. B11, Leuconostoc gelidum, Pediococcus pentosaceus 가 생산하는 최고 amylase 활성은 각각 17.85, 17.50, 17.10, 17.10, 3.24 U/ml이었고, 최고 pretense 활성은 각각 22.48, 22.04, 23.76, 12.13, 3.80 U/ml이었다. 따라서 이 균주들은 발효 현미 제조를 위한 접종균주로서 이용이 가능하리라 사료된다. Brown rice contains rice bran and germ with higher nutritional value and dietary fiber content compared with the polished rice. However, brown rice has a limitation of poor digestion. fermented brown rice could be better nutritional source and improve digestibility. Therefore, we tried to select good fermentative microorganisms which have nutritional values with high amylase and protease activities, and probiotic effects. Nineteen micro-organisms, including eight Bacillus strains isolated from Chongkukjang and 11 lactic acid bacteria, were screened for the fermentation ability and enzyme production. The liquid broths containing 2.5%(w/v) of raw brown rice powder as a sole nutritional source were used for culture media. Among the strains tested, all of the Bacillus strains and two lactic acid bacteria (Leuconostoc gelidum and Pediococcus pentosaceus) showed increase in cell population and enzyme activities. The viable cell counts of all the Bacillus strains and two lactic acid bacteria exceeded $10^7 CFU/mL$. The maximal enzyme activities produced by Bacillus sp. Bl, Bacillus sp. B2, Bacillus sp. B11, L. gelidum and P. pentosaceus were 17.85, 17.50, 17.10, 17.10 and 3.24 U/mL for amylase and 22.48, 22.04, 23.76, 12.13, and 3.4 U/mL for pretense, respectively. Therefore, the results of this study demonstrated that the above strains could be potential starters for the fermentation of raw brown rice.

공간적 특성이 항생제 내성 유전자 존재량에 미치는 영향: 한강 권역을 중심으로

김강민(Kangmin Kim),황태건(Taekeon Hwang),차창준(Chang-Jun Cha),황철수(Chul Sue Hwang) 대한지리학회 2021 대한지리학회 학술대회논문집 Vol.2021 No.6