Statistical Studies Based on SiO and $H_2O$ Maser Survey toward Evolved Stars

김재헌,조세형,김상준,Kim, Jaeheon,Cho, Se-Hyung,Kim, Sang-Joon 한국천문학회 2012 天文學會報 Vol.37 No.2

We report extensive statistical analyses based on the simultaneous observational results of SiO and $H_2O$ masers toward 166 known both SiO and $H_2O$ maser sources (Kim et al. 2010), 83 known SiO maser sources (Cho & Kim 2012 submitted), and 152 known $H_2O$ maser sources (Kim et al. 2012 in preparation). We investigate mutual relations between SiO and $H_2O$ maser properties (peak and total flux density ratios, full line width ratios, and velocity structures etc.) according to stellar pulsation phases and type of evolved stars. These statistical results are compared with monitoring observational results of some individual stars. In addition, a relation between the full line width of SiO/$H_2O$ masers and stellar mass loss rates is examined. For 401 observed stars, we also investigate characteristics of SiO and $H_2O$ maser properties related with evolutionary stages in the IRAS two-color diagram.

디지털 크리처 제작 기술 동향

김재헌,성만규,김상원,장성준,김예진,최병태,Kim, Jae-Heon,Seong, Man-Gyu,Kim, Sang-Won,Jang, Seong-Jun,Kim, Ye-Jin,Choe, Byeong-Tae 한국전자통신연구원 2007 전자통신동향분석 Vol.22 No.4

디지털 크리처란 인간, 동물 그리고 영화 "반지의 제왕"의 "골룸"이나 영화 "괴물"의 "괴물" 같은 상상 속의 캐릭터뿐만 아니라 나무나 숲과 같은 식물을 포함한 실사 수준의 영상으로 표현되는 디지털 생명체를 의미한다. 최근 전세계적으로 흥행에 성공한 블록버스터급의 영화는 대부분 발전한 CG 기술을 바탕으로 감독의 상상력이 그대로 상으로 옮겨진 디지털 크리처가 등장하고 있으며 이로 인해 종래의 단편적인 역할에서 영화의 흥행을 좌우하는 핵심 기술로서 자리잡아 가고 있다. 특히, 영화 등 디지털콘텐츠의 세계시장 규모를 생각하면 이러한 기술의 경제적인 중요성은 매우 크다고 할수 있다. 본 논문에서는 이러한 디지털 크리처를 제작하기 위해 필요한 대표 기술들의 기술동향을 분석하고자 한다.

반도체 광증폭기를 이용한 10 Gb/s 전광 AND논리소자

김재헌,김병채,변영태,전영민,이석,우덕하,김선호,Kim, Jae-Hun,Kim, Byung-Chae,Byun, Young-Tae,Jhon, Young-Min,Lee, Seok,Woo, Deok-Ha,Kim, Sun-Ho 한국광학회 2003 한국광학회지 Vol.14 No.2

반도체 광증폭기의 이득포화원리를 이용한 전광 AND논리소자가 10 Gb/s에서 처음으로 구현되었다. 먼저 첫 번째 반도체 광증폭기에 B 신호를 입력시켜 반전된 신호인 Boolean (equation omitted)이 얻어졌다. 이와 같이 반전된 신호는 두 번째 반도체 광증폭기에 A신호와 함께 동시 입력되어 AND논리소자의 특성이 얻어졌다. By using gain saturation of semiconductor optical amplifiers (SOAs), an all-optical AND gate at 10 Gb/s has been successfully demonstrated. Firstly, Boolean (equation omitted) has been obtained using the first SOA with signal B and clock injection. Then, the all-optical AND gate is achieved using the second SOA with signals A and (equation omitted) injection.

Iron Containing Superoxide Dismutase of Streptomyces subrutilus P5 Increases Bacterial Heavy Metal Resistance by Sequestration

김재헌,한광용,정호진,이정남,Kim, Jae-Heon,Han, Kwang Yong,Jung, Ho Jin,Lee, Jungnam The Microbiological Society of Korea 2014 미생물학회지 Vol.50 No.3

Streptomyces subrutilus P5가 생산하는 철 함유 superoxide dismutase (FeSOD)에 의한 중금속 독성의 완화를 조사하였다. 0.1 mM의 납이온이 120분 처리되면 E. coli $DH5{\alpha}$의 생존율이 7%에 불과 하지만 $0.1{\mu}M$의 정제된 천연 FeSOD가 첨가되면 생존율이 39%로 높아졌다. 이러한 해독작용은 0.01 mM의 구리이온에 대해서도 나타나며(생존율이 6%에서 50%로 증가) 그 효과는 EDTA보다 강하였다. 6xHis-tagged FeSOD를 생산하는 재조합 E. coli M15[pREP4]는 0.1 mM의 납 이온이 60분 처리된 후의 생존율이 3%에서 19%로 증가하였다. 6xHis-tagged FeSOD는 분자당 123개의 납과 결합하였다. 따라서 FeSOD가 중금속을 세포와의 접촉으로부터 격리함으로써 중금속이 오염된 환경에서 세균의 생존력을 증가시킨 것으로 사료된다. Mitigation of heavy metal toxicity by iron containing superoxide dismutase (FeSOD) of Streptomyces subrutilus P5 was investigated. For E. coli $DH5{\alpha}$, the survival rate in the presence of 0.1 mM lead ions was only 7% after 120 min; however, with the addition of $0.1{\mu}M$ of purified native FeSOD the survival rate increased to 39%. This detoxification effect was also shown with 0.01 mM copper ions (survival increased from 6% to 50%), and the effect was stronger than with the use of EDTA. E. coli M15[pREP4] producing 6xHis-tagged FeSOD was constructed, and this showed an increase in survival rates throughout the incubation time; in the presence of 0.1 mM lead ions,the final increase at 60 min was from 3% to 19%. The FeSOD absorbed about 123 g-atom lead per subunit; therefore, we suggest that FeSOD could sequestrate toxic heavy metals to enhance bacterial survival against heavy metal contamination.

신경가동성에 대한 신경생물학과 신경생역학적 이해

김재헌,육군창,배성수,Kim Jae-Hun,Yuk Goon-Chan,Bae Sung-Soo 대한물리치료학회 2003 대한물리치료학회지 Vol.15 No.2

Nervous system is clinically important, and involved in most disorders directly or indirectly. It could be injury and be a source of symptoms. Injury of central or peripheral nervous system injury may affect that mechanism and interrupt normal function. An understanding of the concepts of axonal transport is important for physical therapist who treat injury of nerves. Three connective tissue layers are the endoneurium, perineurium, epineurium. Each has its own special structural characteristics and functional properties. The blood supply to the nervous system is well equipped in all dynamic and static postures with intrinsic and extrinsic vasculation. After nerve injury, alternations in the ionic compression or pressures within this environment may interfere with blood flow and, consequently conduction and the flow of axoplasm. The cytoskeleton are not static. On the contrary, elements of the cytoskeleton are dynamically regulated and are very likely in continual motion. It permits neural mobility. There are different axonal transport systems within a single axon, of which two main flows have been identified : First, anterograde transport system, Secondly, retrograde transport system. The nervous system adapts lengthening in two basic ways. The one is that the development of tension or increased pressure within the tissues, increased intradural pressure. The other is movements that are gross movement and movement occurring intraneurally between the connective tissues and the neural tissues. In this article, we emphasize the biologic aspects of nervous system that influenced by therapeutic approaches. Although identified scientific information in basic science is utilized at clinic, we would attain the more therapeutic effects and develop the physical therapy science.

축구에서 배우자

김재헌,Kim, Jae-Heon 대한양계협회 2006 월간 양계 Vol.38 No.6

발과 족관절의 운동학적 분석

김재헌,Kim, Jae-Hun 대한고유수용성신경근촉진법학회 2008 PNF and Movement Vol.6 No.3

Purpose : To describes the important aspects of the foot and ankle movement and function used when git and balance strategy. Method : The foot and ankle was a very important roles in the lower limb movement and gait. This study summarizes the physiologic movement of knee to the PNF lower extremity patterns. Result : The ankle joint composed of the talocural joint, the subtalarl joint, transverse tarsal joint, talocalcaneonavicular joint. The onset of dorsiflexion muscle activity starts in pre swing gait patterns. First contract muscle is the extensor hallucis. Activity of tibialis anterior and extensor digitorum longus quickly follows in mid swing gait phase. During stance phase, the soleus and gastrocnemius muscle provided plantar flexor torque, which muscle reacts quickly to restrain ankle dorsiflexion, and contributes modulated control of the ankle motion in gait patterns. Conclusions : The understanding of ankle kinematics, could provide a good therapeutic approach for improving gait patterns in patients with various pathological condition.

All-optical logic gates using semiconductor optical amplifier based devices and their applications

김재헌,우덕하,이석,김선호,Young Il Kim,전영민,Young Tae Byun 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.45 No.2

By using two main eects of cross-gain modulation and cross-phase modulation in semiconductor optical amplier-based devices, many logic functions of logic AND, OR, XOR, NOR and XNOR are successfully demonstrated. Also, complex systems including all-optical half and full adders in a combination of multiple logic functions are successfully demonstrated. These functions will provide not only increased speed and capacity of telecommunication systems, but also various functionalities including optical packet switching, decision making, basic or complex optical computing, and many other optical signal-processing systems.

터보차저의 공기맥동음 평가를 위한 측정 및 판별법

김재헌,이종규,Kim, Jae-Heon,Lee, Jong-Kyu 한국음향학회 2007 韓國音響學會誌 Vol.26 No.7

터보차저가 장착된 승용디젤엔진차량의 주요 소음원 중 하나로 터보차저 회전체의 기하학적 불균형에 기인한 공기 맥동음을 들 수 있다. 이 소음의 주요 발생부는 일반적으로 터보차저의 컴프레서휠로서 소음기와 같은 후처리 장치에 의해 저감될 수 있지만, 제조비용을 증가시키는 요인이 될 수 있다. 보다 효과적인 방법은 전반적인 기하학적 대칭성을 개선하거나 문제가 될 수 있는 단품을 분별해냄으로써 단품 품질을 관리하는 것이다. 제조상의 문제나 기타 여러 관점에서 볼 때, 단품에 대한품질관리가 보다 효과적이고 적합하다고 할 수 있다. 이를 위해서는, 생산 라인상에서 공기맥동음의 수준을 평가할 수 있는 적절한 판별방법이 필요하다. 본 논문에서는 공기맥동음의 수준을 정확히 측정할수 있는 방법을 소개하고 그 판별기준도 제시하고자 한다. 또한 리그 측정시스템의 신뢰성 평가과 함께, 리그측정결과와 차량측정결과 간의 상관관계도 분석하였다. 25개 샘플에 대한 측정 재현성 검증을 위해 게이지 R&R 기법을 활용하였다. 이와같은 측정 및 분석 결과로부터, 공기맥동음 관점에서 단품의 우열을 판별할수 있는 표준관리값을 제시할 수 있었다. Aero-pulsation noise, generally caused by geometric asymmetry of a rotating device, is one of considerable sources of annoyance in passenger cars using the turbocharged diesel engine. Main source of this noise is the compressor wheel in the turbocharger system, and can be reduced by after-treatment devices such as silencers, but which may increase the manufacturing cost. More effective solution is to improve the geometric symmetry over all, or to control the quality of components by sorting out inferior ones. The latter is more simple and reasonable than the former in view of manufacturing. Thus, an appropriate discrimination method should be needed to evaluate aero-pulsation noise level at the production line. In this paper, we introduce the accurate method which can measure the noise level of aero-pulsation and also present its evaluation criteria. Besides verifying the reliability of a measurement system - a rig test system-, we analyze the correlation between the results from rig tests and those from vehicle tests. The gage R&R method is carried out to check the repeatability of measurements over 25 samples. From the result, we propose the standard specification which can discriminate inferior products from superior ones on the basis of aero-pulsation noise level.

Streptomyces coelicolor A3(2)의 철 함유 superoxide dismutase 2에 의한 중금속 독성 완화

김재헌,이현경,Kim, Jae-heon,Lee, Hyeon-kyoung The Microbiological Society of Korea 2017 미생물학회지 Vol.53 No.2

납, 아연, 카드뮴에 의한 미생물 생장 저해를 변형된 Tris minimal medium을 사용하여 측정하였다. Escherichia coli 균주에 대한 독성의 세기는 아연 > 카드뮴 > 납 순으로 나타났고 Streptomyces coelicolor A3(2)의 철 함유 superoxide dismutase 2를 과발현하는 E. coli 균주는 중금속 저항성이 증가되었음을 알 수 있었다. Bacterial growth inhibition by lead, zinc and cadmium was measured by using modified Tris minimal medium. The toxicity against Escherichia coli strain was in the order of zinc> cadmium> lead, and the Escherichia coli strain overexpressing iron-containing superoxide dismutase 2 of Streptomyces coelicolor A3(2) was found to have resistance to heavy metals.