Production of γ-Aminobutyric Acid Using Immobilized Glutamate Decarboxylase from Lactobacillus plantarum

이상재,이한승,이동우,Lee, Sang-Jae,Lee, Han-Seung,Lee, Dong-Woo The Korean Society for Microbiology and Biotechnol 2015 한국미생물·생명공학회지 Vol.43 No.3

효율적인 γ-aminobutyric acid (GABA)의 생산을 위해 Lactobacillus plantarum WCFS1로부터 글루탐산 탈탄산효소(glutamate decarboxylase, GAD)를 대장균에 발현, 정제 후 silica beads에 covalent coupling 방법을 이용하여 고정화하였다. 고정화된 효소의 특성을 고정화하지 않은 효소와 비교한 결과, 모든 pH의 범위(pH 3.5–6.0)에서 80% 이상의 활성을 나타내었으며 pH 안정성과 열 안정성 모두 증대되었다. 이 고정화 효소를 packed-bed reactor에 충진하여 GABA의 생산성을 확인한 결과 1리터당 1시간에 최대 41.7 g의 GABA 생산이 가능한 것으로 확인되었다. The glutamate decarboxylase gene (gadB) from Lactobacillus plantarum WCFS1 was cloned and expressed as an N-terminal hexa-histidine-tagged fusion protein in Escherichia coli BL21 (DE3) as the host strain. Purified glutamate decarboxylase (GAD) was immobilized onto porous silica beads by covalent coupling. The pH dependence of activity and stability of the immobilized GAD was significantly altered, when compared to those of the free enzyme. Immobilized GAD was stable in the range of pH 3.5 to 6.0. The resulting packed-bed reactor produced 41.7 g of γ-aminobutyric acid/l·h at 45℃.

중량물 포장

이상재,Lee, Sang-Jae (사)한국포장협회 2012 包裝界 Vol.231 No.-

건강관리코너 - 암예방의 식이요법

이상재,Lee, Sang-Jae 한국화재보험협회 2004 防災와 保險 Vol.101 No.-

Mu-Negative Metamaterial 단일 셀을 가진 듀얼 대역 모노폴 안테나 설계

이상재,이영훈,Lee, Sang-Jae,Lee, Young-Hun 한국전기전자학회 2017 전기전자학회논문지 Vol.21 No.3

This paper was studied the double-band monopole antenna design with Mu-negative metamaterial unit cell, which operates at 700MHz and 2.45GHz band. Mu-negative unit cell made of the interdigital capacitor structure to operate a double-band antenna by inserting it into an antenna radiator unit. In addition, the parasitic conductor is implemented on the back side of the antenna radiation part, so that the resonance point of the antenna can be controlled and the bandwidth is improved. Finally, we implemented an antenna operating in the 750MHz UHD band and the 2.45GHz WiFi band. The designed antenna has a size of $200{\times}100mm^2$. Experimental results show that the 8dB bandwidth and gain characteristics at 750MHz band are 320MHz(42.7%), 5.28dB, 6dB bandwidth and gain at 2.45GH are 540MHz (21.6%), -0.46dB. From the experimental results, we confirmed that the resonance point with theoretical value is in agreement with experimental value, and the radiation patterns are have the omnidirectional characteristic in both bands. 본 논문에서는 Mu-negative Metamaterial 단일 셀을 사용하여 700MHz대역과 2.45GHz 대역에서 동작하는 이중대역 모노폴 안테나 설계에 관하여 연구하였다. Mu-negative metamaterial 단일셀은 interdigital capacitor 구조를 사용하였고, 안테나 방사부에 삽입함으로써 이중대역 안테나를 구현하였다. 또한 기생도체를 안테나 방사부 뒷면에 있도록 구현하여 안테나의 공진점을 제어할 수 있고, 대역폭을 개선하였다. 최종적으로 750MHz UHD대역과 2.45GHz WiFi 대역에서 동작하는 안테나를 구현하였다. 설계제작한 안테나의 크기는 $200{\times}100mm^2$이고, 실험 결과 750MHz 대역에서 8dB 대역폭과 이득특성은 각각 320MHz(42.8%), 5.28dB, 2.45GHz에서 6dB 대역폭과 이득은 540MHz(21.6%), -0.46dB이다. 공진점은 이론값과 실험값이 일치하였으며, 방사패턴은 두 대역에서 전방향 특성을 갖고 있음을 확인하였다.

평면 엔드밀의 최적 가공조건을 위한 실험계획법의 적용

이상재,배효준,서영백,박흥식,전태옥,Lee, Sang-Jae,Bae, Hyo-Jun,Seo, Young-Baek,Park, Heung-Sik,Jun, Tae-Ok 한국기계가공학회 2003 한국기계가공학회지 Vol.2 No.3

The End-milling has been widely used in the industrial world because it is effective to cutting working with various shape. Recently the end-milling is demanded the high-precise technique with good surface roughness and rapid manufacturing time for precision machine and electronic elements. The cutting working of end-milling such as, cutting direction, revolution of spindle, feed rate and depth of cut have an effect on optimum surface roughness. This study was carried out to decide the working condition for optimum surface roughness and rapid manufacturing time by design of experiment and ANOVA. From the results of this study, the optimum working condition for end milling is upward cutting in cutting direction, 600rpm in revolution of spindle, 240mm/mm in feed rate, 2mm in axial depth of cut and 0 25mm in radial depth of cut. The design of experiment has become an useful method to select optimum working condition mend-milling.

HSB800 고강도 보 부재의 연성 능력에 따른 판폭두께비 평가

이상재,문기훈,한상환,하태휴,김진호,Lee, Sang-Jae,Moon, Ki-Hoon,Han, Sang-Whan,Ha, Tae-Hyu,Kim, Jin-Ho 대한건축학회 2011 대한건축학회논문집 Vol.27 No.5

The propose of this study is to evaluate the width-thickness ratio of the HSB800 steel beams satisfying the rotation demand (R) required for compact section. To investigate the properties of HSB800, coupon tests were conducted, from which HSB800 has the three properties - high yield ratio, low strain-hardening ratio, and small strain capacity. The rotation capacity of the HSB800 steel beams are evaluated using finite element analysis (FEA). From the FEA results, the rotation capacity (R>3) of HSB800 steel beams do not satisfy the limiting value specified in current code. Based on the experiment and theories, this study propose a limiting value of the width-thickness ratio of HSB800 for R>3.

${\ll}$준생팔전${\gg}$에 기재된 진희이이십사절기좌공도인법(陳希夷二十四節氣坐功導引法)에 대한 연구 I - 춘계양생(春季養生) -

이상재,이송실,김광호,Lee Sang-Jae,Lee Song-Shil,Kim Kwang-Ho 대한예방한의학회 2001 대한예방한의학회지 Vol.5 No.2

Jinhee-Twentyfour method Qigong (陳希夷二十四節氣坐功導引) is a traditional exercise which is known as qi-gong. It was first mentioned in ${\ll}$保生心鑒${\gg}$ published in Myung dynasty. But it is very difficult to know how to master Jinhee-Twentyfour method Qigong (陳希夷二十四節氣坐功導引) So we studied the training methods by analizing several books such as ${\ll}$遵生八${\gg}$ and ${\ll}$內外功圖說輯要${\gg}$ which have pictures of the training methods. It is known that to train Jinhee-Twentyfour method Qigong (陳希夷二十四節氣坐功導引) is not only limited to the exercise of the body but also training of the mind is an important factor. It is very important to know that the system of Hyung(形), Qi(氣), Sin(神) is needed for Jinhee-Twentyfour method Qigong (陳希夷二十四節氣坐功導引)

A Survey on Understanding of Qi Deficiency in Koreans

이상재,이향숙,Lee, Sang-Jae,Lee, Hyang-Sook Society for Meridian and Acupoint 2009 Korean Journal of Acupuncture Vol.22 No.1

Objectives : To identify whether and how Korean people understand 'qi deficiency' and related symptoms. Methods : We developed a questionnaire based on the experts' comments and modification asking understanding of 'qi deficiency' and symptoms or situations related with it. Total 128 workers at community healthcare centres across the country completed the questionnaire. They were asked if they know the meaning of the word 'qi deficiency' and to give at least three symptoms or situations that they conceive are related with 'qi deficiency'. The responses were collected and descriptive and frequency analyses were performed. Results : Approximately 79.7% of responders answered that they understand the meaning of the word 'qi deficiency' and of them, 71.6% reported that they experience 'qi deficiency' sometimes or more. Regarding somatic or condition-related responses in qi deficiency, lack of power or energy (26.6%), tiredness or fatigue (22.2%), dizziness (7.2%) or sweating (6.3%) were the most frequently reported symptoms. They related symptoms such as loss of appetite (4.3%) or easily catching colds (2.4%) with qi deficiency. Factors described in traditional pattern recognition of qi deficiency were not exactly matched with the responses from this survey. Conclusions : Korean people have rather a broad concept of qi deficiency covering a range of symptoms and this should be taken into account in developing a deficiency assessment tool.

과별 원가계산 모델개발에 관한 연구

이상재,Lee, Sang-Jae 대한병원협회 1997 대한병원협회지 Vol.26 No.12

체내이식 무선기기용 디지털 모뎀의 설계 및 구현

이상재,김태민,Lee, Sang-Jae,Kim, Tae-Min 한국전기전자학회 2012 전기전자학회논문지 Vol.16 No.1

본 논문에서는 체내 이식 무선기기용 디지털 모뎀을 국제표준화에 맞는 주파수 402~405Mhz 대역에서 작동하는 저출력 무선시스템으로 설계하고 구현하였다. 저전력 모뎀 ${\pi}$/4-D8PSSK는 전력 효율적인 변복조 방식으로 저전력 특성이 우수할 뿐만 아니라, 대역 효율적인 변복조 방식으로 PSK의 단점을 극복할 수 있다. 설계된 디지털 모뎀은 Matlab 시뮬레이션 파형과 Chipscope를 이용하여 측정한 파형 비교를 통하여 검증하고 FPGA로 구현하였다. In this paper, a digital modem for the medical implant communication system will operate in 402~405 Mhz wide-band in international standardization frequency was designed and implemented. The ${\pi}$/4-D8PSSK modem, which is not only power effective with a good low-powered characteristics but also band-width effective, can overcome the shortcoming of PSK. The proposed digital modem was verified through the wave comparison based on the result of Matlab simulation and the wave from the measured one using Chipscope, and implemented with FPGA.