Enhancing the Enzymatic Activity of the Multifunctional β-Glycosyl Hydrolase (Cel44C-Man26A_P558) from Paenibacillus polymyxa GS01 Using DNA Shuffling

강영민,강태호,윤한대,조계만,Kang, Young-Min,Kang, Tae-Ho,Yun, Han-Dae,Cho, Kye-Man The Microbiological Society of Korea 2012 미생물학회지 Vol.48 No.2

본 연구자들은 이전에 cellulase, xyalnase 및 lichenase의 다기능 효소활성을 지니는 절단된 Cel44C-$Man26A_{P558}$의 ${\beta}$-glycosyl hydrolase를 보고하였다. 본 연구에서는 절단된 Cel44C-$Man26A_{P558}$ 효소의 다기능성 ${\beta}$-glycosyl hydrolase 활성을 증가시키기 위해 DNA shuffling을 시도하였다. DNA shuffling에 의해 단일변이(P438A)를 가진 M2Cel44C-$Man26A_{P558}$와 이중변이(A273T 및 P438A)를 가진 M21Cel44C-$Man26A_{P558}$를 얻었다. 이중변이를 가진 M21Cel44C-$Man26A_{P558}$은 단일변이를 가진 M2Cel44C-$Man26A_{P558}$ 보다 효소활성이 낮게 나타났으나, M2Cel44C-$Man26A_{P558}$와 M21Cel44C-$Man26A_{P558}$은 대조구인 Cel44C-$Man26A_{P558}$ 보다 약 1.3에서 2.2배 정도 높은 효소활성을 나타내었다. 특히, 단일변이를 가진 M2Cel44C-$Man26A_{P558}$는 대조구인 Cel44C-$Man26A_{P558}$보다 cellulase, xylanase 및 lichenase 효소활성이 약 1.5에서 2.2배 정도 높게 나타났다. ${\beta}$-Glycosyl hydrolase의 cellulase, linchenase 및 xylanase 최적 효소활성은 각각 pH 7.0, 7.0 및 6.0에서 이었다. 이러한 결과는, 아미노산 잔기인 Ala438이 다기능성 ${\beta}$-glycosyl hydrolase 활성을 증가시키는 중요한 역할을 한다고 추정할 수 있다. We previously reported that the truncated Cel44C-$Man26A_{P558}$ ${\beta}$-glycosyl hydrolase protein exhibits multifunctional activities, including cellulase, xylanase, and lichenase. DNA shuffling of the truncated Cel44C-$Man26A_{P558}$ enzyme was performed to enhance the enzymatic activity of the multifunctional ${\beta}$-glycosyl hydrolase. Two mutant enzymes, M2Cel44C-$Man26A_{P558}$ that carries one mutation (P438A) and M21Cel44C-$Man26A_{P558}$ that carries two mutations (A273T and P438A) were obtained. The enzymatic activity of the M21Cel44C-$Man26A_{P558}$ double mutant was lower than enzymatic activity of the single mutant (M2Cel44C-$Man26A_{P558}$). However, both mutants displayed the enhancements in their enzyme activities that were ${\approx}1.3$- to 2.2-fold higher than the original enzymatic activity in Cel44C-$Man26A_{P558}$. In particular, the mutant M2Cel44C-$Man26A_{P558}$ exhibited an approximate 1.5- to 2.2-fold increase in the cellulase, xylanase, and lichenase activities in comparison with the control (Cel44C-$Man26A_{P558}$). The optimum cellulase, linchenase, and xylanase activities of ${\beta}$-glycosyl hydrolase were observed at pH 7.0, pH 7.0 and pH 6.0, respectively. These results, therefore, suggest that the amino acid residue Ala438 plays important roles in the enhancement of the activity of multifunctional ${\beta}$-glycosyl hydrolase.

Domain Isolated Kernel: A lightweight sandbox for untrusted kernel extensions

Manè,s, Valentin J.M.,Jang, Daehee,Ryu, Chanho,Kang, Brent Byunghoon North-Holland 2018 Computers & security Vol.74 No.-

<P><B>Abstract</B></P> <P>Monolithic kernel is one of the prevalent configurations out of various kernel design models. While monolithic kernel excels in performance and management, they are unequipped for runtime system update; and this brings the need for <I>kernel extension</I>. Although kernel extensions are a convenient measure for system management, it is well established that they make the system prone to rootkit attacks and kernel exploitation as they share the single memory space with the rest of the kernel. To address this problem, various forms of isolation (e.g., making into a process), are so far proposed, yet their performance overhead is often too high or incompatible for a general purpose kernel. In this paper, we propose Domain Isolated Kernel (DIKernel), a new kernel architecture which securely isolates the untrusted kernel extensions with minimal performance overhead. DIKernel leverages hardware-based memory domain feature in ARM architecture; and prevents system manipulation attacks originated from kernel extensions, such as rootkits and exploits caused by buggy kernel extensions. We implemented DIKernel on top of Linux 4.13 kernel with 1500 LOC. Performance evaluation indicates that DIKernel imposes negligible overhead which is observed by cycle level microbenchmark.</P>

국내기업 적용을 위한 학습민첩성의 개념정의와 구성요인에 관한 탐색적 연구

강금만(Kang, Kum-man),김민재(Kim, Min-jae),송영수(Song, Youngsoo) 한국경영교육학회 2020 경영교육연구 Vol.35 No.6

[연구목적] 학습민첩성은 Lombardo and Eichinger(2000)가 그 개념을 최초로 주창한 이래 다양한 관점에서 개념정의와 구성요인 연구가 이루어졌으나 국내기업에의 적용을 위한 목적에서의 연구는 상대적으로 미흡하였다. 이에 실천적 관점에서 국내기업에의 적용을 위한 학습민첩성의 개념정의와 구성요인을 탐색해보고 시사점을 제공하고자 하였다. [연구방법] 본 연구는 선행연구에 대한 문헌고찰, 국내 인적자원개발 관련 산학연 전문가를 활용한 델파이 기법, 초점집단면접을 연구방법으로 채택함으로써 삼각검증을 실시하였다. 먼저 문헌고찰을 통해 사전적 구성요인을 도출하였고, 산학연 전문가 23명으로부터 3차에 걸친 델파이조사를 통하여 개념정의와 구성요인을 확인하였고, 2차와 3차 델파이조사 뒤에 초점집단면접을 실시하여 최종적인 개념정의와 구성요인을 확정하였다. 이 과정에서 내용타당도비율(CVR)을 파악하여 델파이조사의 타당도를 검토하였다. [연구결과] 국내기업에의 실질적 적용을 위한 학습민첩성의 개념적 정의에 있어서 포괄적 접근 관점에서의 개념정의가 이루어졌다. 구성요인은 크게 성장지향, 자아성찰, 관계지향, 변화지향, 유연한 사고, 도전적 실험의 6개가 도출되었다. [연구의 시사점] 학습민첩성 구성요인을 확인함으로써 실천적 관점에서의 교육과정 개발과 상관관계 분석을 위한 토대를 제공할 수 있다. [Purpose] Since Lombardo and Eichinger(2000) advocated the concept of learning agility, a lot of studies had been conducted worldwide. But the research for the purpose of applying to Korean companies is relatively insufficient. The purpose of this study is to explore the conceptual definition and constructs of learning agility from a practical point of view. [Methodology] For this purpose, we conducted triangulation by adopting literature review, 3-round Delphi method, and 2-round focus group interview. 23 experts from universities, research institutes and industries participated in the Delphi survey. CVR(Content Validity Ratio) was used as a criteria for the selection of constructs. [Findings] The characteristic of learning agility concept derived from Delphi method and FGI is that it takes the comprehensive approach. 6 major constructs of growth-oriented, self-reflective, relationship-oriented, change-oriented, flexible thinking, and challenging experiments are derived. [Implications] Identified constructs provide a foundation for curriculum development and correlation analysis from a practical perspective. As a result, it can help reinforce learning agility in Korean companies.

단무지 공장에서 발생한 질식 사고의 원인과 방사선학적 소견: 중례보고 및 가스분석 결과

박충기,김만구,김흥철,안범규,박만수,황우철,최철순,강익원 江原大學校 附設 環境硏究所 1994 環境硏究 Vol.11 No.-

목 적:단무지 공장에서 질식사고를 일으켰던 가스의 종류를 알아내고, 이러한 가스중독의 방서선학적 소견을 소개하기 위하여 본 연구를 하였다. 대상 및 방법:단무지 공장에서 발생한 질식 사고자 3예중 생존자 1예를 대상으로 단순흥부X-선검사와 CT 소견을 분석하였으며, 가스의 종류를 알아내기 위하여 단무지를 유리병에 넣어 발생된 가스를 가스크로마토그래픽을 이용하여 분석하였다. 결 과:단무지 공장에서 발생한 질식사고자중 생존한 1명의 방사선학적 검사에서 신속히 호전되는 폐경결(consolidation)을 볼 수 있었으며 이는 폐부종의 소견임을 알 수 있었다. 협기성 상태에서 단무지를 담은 유리병의 상층부 가스를 실험 분석한 결과 이산화탄소, 에칠알코올이 다량으로 검출되었으나 독성가스는 주로 황화수소이였다. 결 론:단무지 공장의 질식 사고자에서 폐방사선학적 소견은 폐경결을 보이는 폐부증으로서 이는 실험을 통해 단무지에서 발생되는 유독가스인 황화수소 때문임을 입증하였다. Purpose: To identify the main toxic gas released from salted radish in rice bran(Dan-M-Ji) and to introduce the radiological findings of the patient who was exposed to the gas. Materials and Methods: Chest radiographs and CT scans of one survivor among three men who were exposed to the gas from Dan-Mu-Ji were reviewed. Gas obtained from the closed bottle containing Dan-Mu-Ji was analized by using the gas chromatography. Results: The radiographlc examinations of the survivor were suggestive of pulmonary edema with it's rapidly improving consolidations in both lung. The headapace gas within the bottle containing Dan-Mu-Ji was mainly composed with carbon dioxide, ethyl alcohol and hydrogen sulfide, of which hydrogen sulfide was considered the main toxic gas released. Conclusion: Under the anaerobic condition, Dan-Mu-Ji released toxic hydrogen sulfide. Inhalation of hydrogen sulfide might produce non-cardiogenic pulmonary edema.

ADVANCED MMIS TOWARD SUBSTANTIAL REDUCTION IN HUMAN ERRORS IN NPPS

Seong, Poong Hyun,Kang, Hyun Gook,Na, Man Gyun,Kim, Jong Hyun,Heo, Gyunyoung,Jung, Yoensub Korean Nuclear Society 2013 Nuclear Engineering and Technology Vol.45 No.2

This paper aims to give an overview of the methods to inherently prevent human errors and to effectively mitigate the consequences of such errors by securing defense-in-depth during plant management through the advanced man-machine interface system (MMIS). It is needless to stress the significance of human error reduction during an accident in nuclear power plants (NPPs). Unexpected shutdowns caused by human errors not only threaten nuclear safety but also make public acceptance of nuclear power extremely lower. We have to recognize there must be the possibility of human errors occurring since humans are not essentially perfect particularly under stressful conditions. However, we have the opportunity to improve such a situation through advanced information and communication technologies on the basis of lessons learned from our experiences. As important lessons, authors explained key issues associated with automation, man-machine interface, operator support systems, and procedures. Upon this investigation, we outlined the concept and technical factors to develop advanced automation, operation and maintenance support systems, and computer-based procedures using wired/wireless technology. It should be noted that the ultimate responsibility of nuclear safety obviously belongs to humans not to machines. Therefore, safety culture including education and training, which is a kind of organizational factor, should be emphasized as well. In regard to safety culture for human error reduction, several issues that we are facing these days were described. We expect the ideas of the advanced MMIS proposed in this paper to lead in the future direction of related researches and finally supplement the safety of NPPs.

韓國의 氣壓配置氣候學的 考察

姜萬石 대구효성가톨릭대학교 1979 연구논문집 Vol.21 No.2

Recently, it is frequently taken for the synoptic climatological method to investigate the climatic characteristics by dealing with air currents, pressure fields, air masses, and weather types synthetically. In this paper, the daily pressure patterns for twenty years 1956~1975 in Korean are classified six major typers and eleven minor types by the Yoshino-Fukuoka's approack (1967). The characteristics of every types is explained by the monthly and five-day periods of pressure patterns. According to the singularities from curves of five-day frequency of pressure patterns, I determine the duration of ten natural seasons. Through the above procedure the findings are as follows: (1) According to the monthly frequency of pressure pattern types, the winter monsoon pattern shows the highest frequency in December, January, and February, the frequency of the migratory hign pattern and the trough reveals largely in March, April, and November, the frontal pattern occurs much in July and August, and the migratory high does frequently in May, June, September, and October. And according to the annual frequency of pressure pattern, the migratory high occupies the highest position as 33.9%, secondly the trough, the frontal, the winter monsoon, and the summer reach 24.3%~4.3%, the typhoon with the least frequency is more than 2.0%. (2) The frequency of the winter monsoon pattern is dominant in winter, the frequency of the frontal, the summer, and the typhoon is high in summer, and that of the trough is great in spring, autumn, an winter. (3) As a result of examining the monthly frequency of the five-year periods about main pressure pattern types, the months trend to increase in the frequency of these periode come out a ascendant tendency as approaching of up-to-date, on the contrary the months which are in a decreasing trend show the few frequency as coming up to the recent periods. (4) Considering th fluctuation of curves of five-day frequency in the tenyear periods (1956~1965, 1966~1975) and the twenty -year period (1956~1975), there are some differences. This is due to have been influenced on the seasonal change by the climatic fluctuation. (5) Natural seasons are divided into ten seasons by the singularities of five-day periods of pressure patterns, namely, winter, late winter, early spring, spring,early summer, the Jangma, summer, the Ga-eul Jangma, autumn, and early winter. Winter continues for five months from November to March, spring appears in April and May, Summer does in June, July, and August, and autumn is composed of September and October, This seasonal calendar is different from the common one in the duration of every season with a difference of one or two months.

韓國의 氣溫의 因子分析

姜萬石 대구효성가톨릭대학교 1996 연구논문집 Vol.53 No.2

The monthly regionality and its factors of the daily average temperature observed from 1931 to 1990 are analized with the factor scores in 66 stations. In the distribution of the temperature in spring(from March to May), the regionality appears in the inland and the coast owing to the temperature in summer(from June to August) appears along the E-W direction due to the inflows of the westerly winds in the greater part of whole country, on the other hand the maritime high has influence on the southern region during August. And the one in autumn(from September to October) does along the S-N direction in the southern region and the E-W direction in the cental region. The factors of the latitude and the sea have influence on the southern region, while the ones of the westerly wind and Taebek mountain range do on the cental region. The regionality of the winter temperature appears along S-N direction and symmetrizes between the eastern coast and the western coast. These phenomena have been influenced by the factors of the north-westerly or westerly winds, the latitude, the distribution of land water and Taebek mountain range. The local characteristics of the distribution of the temperature can be found in some regions. The regionality in Cheju-do due to the influence of the latitude and the sea appears in autumn and inter(from January to march, from September to December), while the counterpart in the eastern slopes owing to the influence of Taebek mountain range and the current seems to reflect during the period except June and August. In the case of Ullung-do caused by the influence of the sea, the regionality appears during the three seasons except winter evidently during July. The temperature in Taegwallyong caused by the altitude shows the particularity during the period except January and December.

韓國 豪雨의 氣候學的 特性

姜萬石 대구효성가톨릭대학교 1992 연구논문집 Vol.44 No.1

The distribution of heavy rainfalls in both the monthly occurrence and the causal one, and the trend of the occurrence of heavy rain are analized with the data observed during 1920-1939 and 1971-1989. The regional classification is carried out by using the six factors. The synoptic analysis of the six cases is performed. The heavy rain mostly occurs during the rainy season from June to September, and the heavy rainfall results from such pressure systems as extratropical cyclone, changma front and typhoon. The areas with frequen시 heavy rains are the southern coastal area, the central area and Cheju-do. In the change of the frequency of heavy rainfalls, it trends towards the decrease in 1920s and 1930s, and does towards the increase in 1970s and 1980s. Such a trend depends greatly upon the changma type and the July type among the six causal types and the four montly types. According to the regional classification based on t도 dendrogram, they are divided into the six regions which are symmerically distributed with the axis crossing through the middle of Chollabuk-do and Kyongsangbuk-do. The inflows of the humid south-westerly or southerly winds at 850mb level are prevalent on the days with the heavy rainfall.

國民學生의 育苗 學習 敎果 增進을 위한 敎材 硏究

姜萬寧 진주교육대학교 1992 論文集 Vol.36 No.-

Lectures have been currently substituted for practical experiments in elementary schools due to the shortage of experimental materials as well as experimental field for practice. The author devised the simple alternative teaching materials for seedling growth and grafting to do experiments. The results are summarized as follows ; 1) Seeds were germinated in a pot in the class room and then were brought home to grow as home projject. 2) Easy handling seeds for elementary students were selected, such seeds as light independent, long lasting, and lese sensitive to water content to germinate. 3) Disposable paper cups were used successfully as a pot. They were easy to get and handle for seediling growth. 4) Sawdust, bricket ashes, and commercial pot mix provided good aeration and proper water holding capacity. They can support seedling growth for 2-3 weeks. 5) Woodplate was used for grafting practice to fix branches.

동기전동기의 정상상태 특성해석

강만원 大田産業大學校 1996 한밭대학교 논문집 Vol.13 No.0201

이 논문은 동기전동기의 해석과 설계를 다루었으며 고정자는 3상 유도전동기의 고정자와 동일하고 회전자는 철극형의 회전계자형이며 인버터는 직접 전원에 접속되었다. 에너지 변환을 담당할 고정자는 전류의 주파수를 제어 할 수 있는 인버터에 접속되었으며 동기모드에서 속도는 인버터 출력전류의 주파수를 가변하므로서 제어될 수 있다. This paper covers analysis and design of a synchronous motor, The stator is equal to that of three phase induction motor, and It’s rotor is rotating field type of salient pole. The inverter is connected to the grid, the stator to take care of energy convertion is connected to the inverter controllable frequency of current. The speed of synchronous mode can be controlled by varying the frequency of the Inverter output current.