단세포 나팔벌레,Stentor coeruleus의 빛에 의한 ATP 합성

Chen, B.H.,허재욱,민태진,Iwatsuki, K,송필순 동국대학교 자연과학연구소 1986 자연과학연구 논문집 Vol.6 No.-

나팔벌레의 세포내 ATP 함량은 0.5~2초동안 40W/m₂백색광을 조사함에 따라 어두운 상태의 대조구에 비하여 급격히 증가하였고, 빛을 계속하여 조사하면 세포내 ATP 함량은 단계적으로 감소하였다. 광수용체 색소 Stentorin 을 포함하고 있는 색소 미립자를 나팔벌레 완전세포로부터 분리하여 이에 ADP와 pi를 가한 혼합물에 빛을 조사하여 ATP가 생성됨을 확인하였다. 나팔벌레 완전세포와 색소미립자주으이 ATP 함량은 변량울에 (fluence rate)의존하였다. 이들 결과로 생명체는 광양자를 ATP로 전이시킬 수 있고, ATP 생성은 나팔벌레 색소미립자의 특성으로 사려된다. The cellular ATP level in Stentor coeruleus jumped above the dark control level when stimulated by 0.5-2 second light pulses (40W/m₂white light). Continued, irradiation fo the cells caused a gradual decline of the cellular ATP level. Pigment granules containing the photoreceptor pigment stentorin isolated from whole cells also exhibited a light-induced ATP synthesis. The ATP level in both whole cells and pigment granules was dependent upon the fluence rate. These results suggest that the organism is capable of tranducing light quanta into ATP and that ATP synthesis is localized in the pigment granule.

Development of lattice inversion modified embedded atom method and its applications

Xianbao Duan,Bing Zhou,Rong Chen,Huamin Zhou,YanweiWen,Bin Shan 한국물리학회 2014 Current Applied Physics Vol.14 No.12

The modified embedded atom method (MEAM) has been widely used in describing the physical properties of elemental crystals, alloys and compounds with multiple lattice structures. We report here the development of a reliable procedure to reduce the complexity of the MEAM formalism by removing the many-body screening function. In the proposed formulation, the interatomic pair potential is obtained by applying Chen-M€obius lattice inversion up to fifth nearest neighbors, so that the cohesive energy curve can be reproduced faithfully. The newly developed model (Lattice Inversion MEAM, LI-MEAM), which can be viewed as a direct extension of the embedded atom method (EAM), no longer requires the computation of many-body screen functions and has fewer adjustable parameters than MEAM. As an illustration, we optimized the potential parameters of body centered cubic iron (bcc-Fe). The values of the calculated physical properties agree well with experimental results. We further investigated the sizedependent melting behavior of bcc-Fe nanoparticles (NPs) with particle size ranging from 725-atom (~25 Å) to 22899-atom (~80 Å) using replica exchange molecular dynamics (REMD) simulations. Our simulations show advantages of LI-MEAM in modeling of the melting process and quantitatively reveals that the liquid skin melting (LSM) process of bcc-Fe NPs.

『열하일기』를 통해 본 18세기 베이징 선남(宣南)의 선비문화

진빙빙 ( Chen Bing Bing ),하오준펑 ( Hao Jun Feng ) 성균관대학교 인문학연구원(성균관대학교 인문과학연구소) 2018 人文科學 Vol.0 No.69

본 논문은 『열하일기』를 통해 18세기 베이징 선남의 선비문화에 대하여 구체적으로 고찰하였다. 선남문화는 베이징문화의 한 징표로 베이징 문화 중에서도 중요한 위치를 차지하고 있다. 청나라 때 실시한 ‘기민분치(旗民分治)’라는 주거정책으로 실시하였기 때문에 한족 사대부와 선비들은 북경성의 도성 밖에 위치한 선남지역에서만 거주할 수 있었다. 시간이 흐르면서 한족 사대부들을 비롯한 선비문화가 베이징 선남의 문화 징표로 형성되었다. 선비들은 이곳에서 학술과 문학사상 교류를 통하여 18세기의 중국 문화예술 발전을 촉진시켰다. 동서고금 문화의 정수가 모인 선남지역은 중국학자뿐만 아니라 외국학자들도 선망하였던 문화의 성지가 되었다. 연암 박지원은 조선 후기 최고의 문학가이자 북학파를 대표하는 실학자였다. 박지원은 1780년 조선 연행사절을 따라 중국으로 출사(出使)하여, 두 달 동안의 일기와 여러 가지의 견문을 수록하여 『열하일기』를 저술하였다. 『열하일기』에는 18세기 중국의 문화와 사회 발전 양상을 많이 기술되어 있다. 특히 한·중 학자들의 만남과 교유, 유리창에서의 사문화(士文化), 선남의 선진적인 서양문화 등을 포함한 베이징의 선남문화에 대해 많이 언급하고 있다. 이 논문은 북경의 선남지역에 초점을 맞추고 이곳에서 이루어졌던 선비문화의 양상을 살펴보고, 나아가 당시 조선 학자들이 베이징의 선남문화에 대해 어떻게 이해하고 인식하였는지를 살펴보고자 한다. The paper aims to examine the scholarly culture of Beijing Xuannan in the 18th century based on the analysis of Jehol Diary written by Bak Jiwon, a noted scholar of the Northern School in the late Joseon dynasty. The culture of Xuannan is an important element for understanding the culture of Beijing. In the Qing dynasty, the government carried out a residential policy according to which the literati and the scholars of the Han nationality were permitted to dwell only in the area of Xuannan. As time went on, the scholarly culture of the Han nationality literati became a symbol of the Xuannan culture. Scholars gathered here for academic and literary exchanges and promoted the development of Chinese culture and arts in the 18th century. The essence of culture at all times and in all places converged on Xuannan, which became a holy land in the hearts of Chinese and foreign scholars. In 1780, Bak Jiwon traveled to China as a member of the government delegation and wrote the famous Jehol Diary. The book records Chinese politics, economy, culture and customs in detail as well as the cultural exchanges between Chinese and Korean literary scholars and intellectuals. He made a lot of efforts to describe Beijing Xuannan culture which includes: the literary trends of the 18th century China; communications among scholars in the Liulichang street and the bookstore culture there; Western learning; and other aspects. This dissertation not only focuses on the aspects of the Xuannan culture mentioned in Jehol Diary by Bak Jiwon as the main research topic but also explores the understanding of the Xuannan culture among the scholars of the Joseon dynasty.

『열하일기』에 나타난 한,중 지식인의 교류양상

진빙빙 ( Bing-bing Chen ) 성균관대학교 인문학연구원(성균관대학교 인문과학연구소) 2016 人文科學 Vol.0 No.61

본 논문은 『열하일기』를 통해 한,중 지식인의 교류양상에 대하여 구체적으로 고찰하였다. 『열하일기』는 연암 박지원이 1780의 중국 사행시, 자제군관의 명목으로 참가하여, 두 달 동안의 일기와 여러 가지의 견문을 수록하여 작성한 작품이다. 그 중에는 중국의 정치,경제,문화,풍습 등 사회 현황을 기록한 것이 외에도, 한중 양국 지식인의 교류에 관한 내용도 많이 언급하고 있다. 『열하일기』에 언급한 문인들은 두 부류로 나누어 볼 수 있다. 전시대 중한 문학교류에 있어 탁월한 인물, 또는 중국에서 연암과 직접 교류하였던 중국 지식인들이다. 이들 간의 문화교류는 중,한 문화교류에 크게 기여하였을 뿐만 아니라, 박지원의 인식, 또는 문예사상에도 큰 영향을 끼쳤다. 이들의 언설을 통하여 한,중 지식인의 교류양상과 중국 사회의 발전현황, 나아가 중국 지식인의 사회인식 등을 파악하고자 하는 것이 이 논문의 연구 목적이다. The paper is aimed at studying the aspects of communications between Chinese and Korean literary intellectuals through the examination of Jehol Diary by Park Ji-won, In the 1780s, Park Ji-won went to China as a military officer on a diplomatic mission and spent more than two years in travelling. After returning to Korea, Park Ji-won compiled his diary written in China and the observations into the well-known Jehol Diary. The book records Chinese politics, economy, culture and customs in detail as well as the cultural exchanges between Korean and Chinese literary intellectuals. Jehol Diary introduces two types of literary intellectuals. One is the major outstanding figures in the earlier times of Korean-Chinese literary exchanges, and the other is Chinese intellectuals Park Ji-won met during his travel to China. Their amiable communication promoted the cultural exchanges between Korea and China, acquainted Park Ji-won with Chinese culture and contributed to his literary creation. The paper aims to examine the communications between Korean and Chinese intellectuals in the 18th century based on the records in Park Ji-won’s works, further comprehend the philosophical trends of Chinese intellectuals and have a better understanding of the society.

Mechanism analysis of pressure fluctuation in wheel loader articulated steering hydraulic system

Bing-wei Cao,Xinhui Liu,Wei Chen,Chen Zhou,Fei-xiang Xu 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.10

This paper studies the influence of hinge point positioning of a steering cylinder on the pressure fluctuation of the steering system of a wheel loader. Affected by the hinge point position of the steering cylinder, the main causes of the pressure fluctuation are found to be the stroke difference and the force arm difference. Based on theoretical analysis, the hinge point positioning of the steering cylinder was optimized by using genetic algorithm (GA). The AMEsim simulation model of the steering system was built to verify the accuracy of the GA. The wheel loader was reformed according to the optimized articulated points position. Steering tests showed a significant drop in system pressure fluctuation, the energy consumed is also reduced. Further, the analysis shows that the force arm difference is the main factor causing the pressure fluctuation, providing the theoretical and experimental basis for the design of a steering system of wheel loaders.

Picosecond Mid-Infrared 3.8 μm MgO:PPLN Optical Parametric Oscillator Laser with High Peak Power

Bing-Yan Chen,Yu-Heng Wang,Yong-Ji Yu,Guang-Yong Jin 한국광학회 2021 Current Optics and Photonics Vol.5 No.2

In this study, a compact, picosecond, mid-infrared 3.8 μm MgO:PPLN optical parametric oscillator(OPO) laser output with high peak power is realized using a master oscillator power amplifier (MOPA)1 μm solid-state laser seeded by a picosecond fiber laser as the pump source. The pump source was a 50MHz and 10 ps fiber seed source. After AOM pulse selection and two-stage solid-state amplification, a 1,064 nm laser output with a repetition frequency of 1–2 MHz, pulse width of 9.5 ps, and a maximum average power of 20 W was achieved. Furthermore, a compact short cavity with a unsynchronized pump is adopted through the design of an OPO cavity structure. When the injection pump power was 15 W and the repetition frequency was 1 MHz, the average output power of idler light was 1.19 W, and the corresponding peak power was 119 kW. The optical conversion efficiency was 7.93%. When the repetition frequency was increased to 2 MHz, the average output power of idler light was 1.63 W, the corresponding peak power was 81.5 kW, and the optical conversion efficiency was 10.87%. At the same time, the output wavelength was measured at 3,806 nm, and the beam quality was M X2 = 3.21 and M Y2 = 3.34.

A study of a new hybrid vibration energy harvester based on broadband-multimode

Bing Chen,Shiqing Li,Xiaolei Tang,Lijie Zhang 국제구조공학회 2021 Smart Structures and Systems, An International Jou Vol.28 No.1

To improve the energy conversion efficiency and working frequency bandwidth of a single frequency piezoelectric vibration energy harvester, a new type of hybrid vibration energy harvester is developed which is combined with the mechanism of piezoelectric and electromagnetic energy conversion. The system comprises of a PZT cantilever beam, an elastic suspended magnetic mass, a magnet block attached to the end of the cantilever beam and a resonator. The addition of resonator can not only increase the mode, but also adjust the frequency of harvester flexibly. Nonlinear magnetic force of magnet block not only broadens the frequency band and improves the output performance of the system, but also changes the resonant frequency to make the harvester have better adjustable performance. On this basis, an improved electromechanical coupled analytical model of continuum is proposed which can be solved by the Runge-Kutta algorithm and the influence of different factors (the mass and spring stiffness of the resonator, as well as the electromechanical coupling coefficient, electromagnetic coupling coefficient, magnet mass and magnetic flux) on the output are analyzed. According to the prototype of the vibration energy harvester developed, an experimental system was built. The performance of the independent and hybrid energy harvesters is evaluated by experimental and analytical methods. The peak output voltage of the piezoelectric part was about 4 times that of the electromagnetic part. The peak output current of the electromagnetic part is about 30 times that of the piezoelectric part. The study results show that the proposed new hybrid vibration energy harvester can achieve a wider frequency range and multimodal vibration energy harvesting. In addition, the bandwidth and power of the harvester can be dynamically adjusted by changing the resonator or electromechanical coupling coefficient, and the bandwidth of the harvester can also be adjusted by changing the quality and characteristics of the magnet.

Molecular Characterization and Expression Analysis of Insulin-like Growth Factor-1 and Insulin-like Growth Factor Binding Protein-1 Genes in Qinghai-Tibet Plateau Bos grunniens and Lowland Bos taurus

Chen, Ya-bing,Fu, Mei,Lan, Dao-liang,Li, Jian Asian Australasian Association of Animal Productio 2015 Animal Bioscience Vol.28 No.1

Insulin-like growth factor-1 (IGF-1) and insulin-like growth factor binding protein-1 (IGFBP-1) play a pivotal role in regulating cellular hypoxic response. In this study, we cloned and characterized the genes encoding IGF-1 and IGFBP-1 to improve the current knowledge on their roles in highland Bos grunniens (Yak). We also compared their expression levels in the liver and kidney tissues between yaks and lowland cattle. We obtained full-length 465 bp IGF-1 and 792 bp IGFBP-1, encoding 154 amino acids (AA) IGF-1, and 263 AA IGFBP-1 protein, respectively using reverse transcriptase-polyerase chain reaction (RT-PCR) technology. Analysis of their corresponding amino acid sequences showed a high identity between B. grunniens and lowland mammals. Moreover, the two genes were proved to be widely distributed in the examined tissues through expression pattern analysis. Real-time PCR results revealed that IGF-1 expression was higher in the liver and kidney tissues in B. grunniens than in Bos taurus (p<0.05). The IGFBP-1 gene was expressed at a higher level in the liver (p<0.05) of B. taurus than B. grunniens, but it has a similar expression level in the kidneys of the two species. These results indicated that upregulated IGF-1 and downregulated IGFBP-1 are associated with hypoxia adaptive response in B. grunniens.

IGBT Neural Network Prediction Method of Radar Transmitter based on Levenberg-Marquard Optimization

Bing Chen,Gang Lu,Hongzhen Fang,Li Ai,Huanzhen Fan 보안공학연구지원센터 2016 International Journal of Future Generation Communi Vol.9 No.9

Periodic Event-triggered Consensus of Multiagent Systems Under Random Packet Dropouts

Bing Chen,Yangzhou Chen,Jingyuan Zhan 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.9

In this paper, the periodic event-triggered consensus problem for linear multiagent systems (MASs) with random packet dropouts in a generic directed communication topology is addressed. Both leaderless and leader-following mean square consensus problems, where the random packet dropouts are described by a Bernoullidistributed sequence, are considered. To solve these problems, a linear transformation matrix is constructed from a given directed spanning tree of the communication topology of the MASs, which equivalently transforms the mean square consensus problem into the corresponding mean square asymptotic stability problem of the derived reduced-order systems with constraints. Then, mean square consensus criteria are derived using the Lyapunov stability theory, which is expressed in terms of linear matrix inequalities (LMIs) concerning the sampling period, the packet dropout probability, and the control gain matrix. To reduce the information updating number, an event-triggered mechanism is designed with fewer unknown parameters. Finally, numerical simulations are given to verify the effectiveness of the theoretical results.