大氣電學-地面與太空觀測 The atmospheric electricity - ground and space observations
陳炳志 所長(成功大學電漿所)
<專題討論>2018/10/11(四)14:10綜合大樓2樓48218教室演講
摘要:
大氣電學主要是研究地球大氣內電荷流動相關的自然現象,電離層與地表間的電荷流動構成了循環,形成大域電路。大域電路由閃電所驅動,涵蓋了許多大氣內有趣的放電現象。近年來的研究顯示電離層的電氣活動也會受到來自與低層大氣、海洋,甚至於地表岩石圈的影響,成為一個新興的重要探索課題。在本次演講中將會介紹目前我們進行中相關的地面與太空觀測,以及近年來在此領域的重要研究成果。
| 附件: 20181011 陳炳志所長.pdf
台灣半導體產業會被中國搶走嗎?
卜令楷 教授(成功大學電機系兼任教授/奇景光電、承景科技前副總經理)
<專題討論>2018/10/4(四)14:10綜合大樓2樓48218教室演講
摘要:
半導體產業是台灣最重要的產業,甚至被稱為「鎮國之寶」。近年大陸積極發展半導體產業,投入大量資本外,也大舉來台灣挖角。台灣的半導體產業有可能像許多製造業⼀樣,逐漸被大陸搶走嗎?我們試著從產業分析的角度來討論這個問題。
半導體產業創造出很多科技新貴。但是同時也是著名的「爆肝」產業。為什麼會這樣?有機會避免嗎?我們一起來討論⼀下。
| 附件: 20181004 卜令楷教授.pdf
Single-particle and collective excitations in layered graphenes
陳炳志 所長(成功大學電漿所)
<專題討論>2018/9/27(四)14:10綜合大樓2樓48218教室演講
摘要:
The generalized .. tight-binding model and the random-phase approximation are developed and combined together to fully the many-particle Coulomb interactions in 2D graphene systems. The intralayer & interlayer hopping integrals, the intralayer & interlayer Coulomb interactions, electric field, and magnetic field are taken into account simultaneously. The electron-hole excitations and plasmon modes are very sensitive to the number of layers, stacking configurations, doping levels, and external fields. Apparently, the (momentum, frequency)-phase diagrams exhibit the diverse Coulomb excitation phenomena. Part of theoretical predictions are consistent with the EELS measurements, while most of them require the further examinations. The dimensionless energy loss functions, being clearly characterized in the current work, are very useful in the near-future studies on (i) the time-dependent plasmon propagation on the 2D planes and (ii) the layer-related Coulomb decay rates.
| 附件: 20180927 林明發教授.pdf
Road to Venus mission in Japan- from curiosity to the realization-
小山孝一郎教授(Asia Space Environment Research Consortium, Kanagawa, Japan)
2018/7/17(二)14:10綜合大樓3樓48312教室演講
In 2015, One Japanese spacecraft was successfully injected into Venus Orbit after failure of orbit injection in 2010, and it became the first orbiter of other planet, which was named “Akatsuki” (暁、Dawn) after its successful injection. The history of Venus exploration are Venera 1-16 in 1961-1983 by USSR. Mariner 2, 5, and 10 by USA in 1962 -1973, Pioneer Venus by USA in 1987. Vega 1, 2 in 1984 by USSR, Magellan in 1989 by USA, and lastly Venus express in 2001 by ESA. We describe here a road to successful Venus mission. We start from the failure of orbit injection in 2010, and successful injection to Venus orbiter in 2015. Then we go back to the history before successful orbit injection. We had a dream to send a Venus probe in 1980’s. The questions we had are: Why Venus has super rotation, Does active volcano exist, Is there lightning ? Is there Aurora ? Why neutral density in the cryosphere suddenly disappears ? . To make our curiosity satisfy, we prepared for the mission, starting from analysis of data obtained with Pioneer Venus, read thick summary book on Venus, and asked private company to start study in late 1980’s. We describe here phenomena which are still not understood. These include instruments to find the clues to solve the problems for Venus mission, and finally orbit selection the spacecraft which is constrained under the limited capability of launcher. Most important task was to find scientists who are keen to send a probe to Venus. Here is a story which we want to convey to young scientists.
地球內部構造與地球磁場 Earth’s interior structure and geodynamo
龔慧貞 副教授(成功大學地科系)
<專題討論>2018/5/10(四)14:10綜合大樓2樓48218教室演講
摘要:
眾所皆知地球因本身磁場所形成的磁層,保護地球生物免於太陽的高能帶電粒子襲擊。從地質資料顯示地球磁場每隔一段時間都會反轉的,也觀察到南北磁極已不同的速度「漫遊」。 近170年來觀測結果顯示,地球磁場強度已減弱~15%。在這報告中,將以地球內部構造來談地球磁場機制,即「地球發電機理論」。
| 附件: 20180510 龔慧貞副教授.pdf
Nanostructure Engineering using Microplasmas: Synthesis and Applications
江偉宏 副教授(臺灣科技大學化學工程學系)
<專題討論>2018/5/3(四)14:10綜合大樓2樓48218教室演講
摘要:
Microplasmas are a special class of electrical discharges formed in geometries where at least one dimension is less than 1 mm. As a result of their unique scaling, microplasmas operate stably at atmospheric pressure and contain large concentrations of energetic electrons (1-10 eV). These properties are attractive for a range of nanomaterials synthesis and nanostructure engineering such as metal nanostructures and carbon-based materials [1-3].
In this presentation, I will discuss these topics in detail, highlighting the advantages of microplasma-based systems for the synthesis of well-defined nanomaterials. These experiments will aid in the rational design and fabrication of nanomaterials and may also have significant impact in emerging applications. Recently, we found that the energetic species including radicals, ions and electrons generated in the microplasmas were capable of initiating electrochemical-assisted reactions for the nucleation and growth of graphene quantum dots [4]. Moreover we develop a simple synthesis of metal nanoparticles/graphene composites using a unique atmospheric-pressure microplasma-assisted electrochemical method. Systematic micro Raman study indicates that the as-produced AgNP/graphene composites show exceptional SERS performance [5].
| 附件: 20180503 江偉宏副教授.pdf
我國太空計畫發展-過去及未來
林俊良 博士(國家太空中心主任)
<專題討論>2018/4/26(四)14:10綜合大樓2樓48218教室演講
摘要:
本簡報將簡介我國太空長程發展計畫第一期(1991-2004)和第二期(2004-2018)的源起及成果。另介紹即將開展的第三期長程計畫(2019-2028),其目標和執行內容。希望藉這個簡報讓大家知悉十年後台灣太空科技發展對國家、產業和人才培育的影響。pheric-pressure plasma and its applications, which include atmospheric-pressure plasma jet (APPJ), plasma activated water (PAW) and plasma activated microbubbles (PAMBs).
| 附件: 20180426 林俊良主任.pdf
In-situ plasma measurements in the Earth’s ionosphere
方惠寬 博士(成功大學電漿所)
<專題討論>2018/3/29(四)14:10綜合大樓2樓48218教室演講
摘要:
Measurements of plasma are fundamental for space physics, especially for space weather. Recently, giant progress of the CubeSat technologies greatly lowers the barrier to insert a satellite into a lower earth orbit for space exploration. Satellite constellation missions consisting of tens of CubeSats is planned and launched. These missions provide multi-point measurements and make it possible to separate spatial and temporal effects regarding couplings between ionosphere, atmosphere and even lithosphere. And the altitude of these missions are rarely explored by conventional satellites because of large air drag and short mission lifetime. In addition to Cubesat missions, simultaneous multi-instrument measurements onboard sounding rockets aiming for the plasma characteristic investigations in the ionosphere D layers, which is the least-explored region in the ionosphere, is planned. In this presentation, the plasma diagnostic techniques onboard CubeSats and sounding rockets will be introduced. The design concepts and preliminary results of the solar EUV probe onboard the Phoenix CubeSat in QB50 mission and the “Mesosphere and Ionosphere Plasma Exploration complex (MIPEX)” instrument onboard the NCKU sounding rocket, which is planned to be launched in 2020, will be shown. These experiments can provide unique high-quality data of the plasma environment to explore the ion distribution and the electrodynamic processes in the Ionosphere.
| 附件: 20180329 方惠寬博士.pdf
Laser and Plasma wakefield acceleration
周紹暐 博士(台灣積體電路製造股份有限公司)
<專題討論>2018/3/27(二)13:10綜合大樓2樓48218教室演講
摘要:
Energetic particle beams are important tool in many application, from basic science to healthcare, also a crucial element to produce high quality X-ray radiation. Conventional accelerators are relative large, from 10 m to several km, due to material-breakdown-limited acceleration gradient and energy loss via synchrotron radiation. Size and cost of maintenance of conventional accelerator limit the extent of application for daily life. Wakefield accelerator driven by either high energy or high energy particle is a promising way to build a table-top accelerator. For example, GeV-scale electron bunch driven by laser pulses has been demonstrated by using cm long gas targets . As a contrast, it needs almost 100 m of conventional accelerator to reach this energy. In this talk, I will first introduce fundamental physic of wakefield accelerator and related experiment. In the end of discussion, a physical phenomenon called "collective deceleration" associated to the unique properties of laser-driven electron bunches will be studied by experiment and PIC simulation.
| 附件: 20180327 周紹暐博士.pdf
Generation of hydrogen, helium and oxygen EMIC waves by fast magnetosonic shocks in the magnetosphere and in the solar wind
李昆翰 博士(中央研究院地球科學研究所)
<專題討論>2018/3/22(四)14:10綜合大樓2樓48218教室演講
摘要:
Electromagnetic ion cyclotron (EMIC) waves are often observed in the magnetosphere and in the solar wind. Here we propose a new generation mechanism for hydrogen, helium and oxygen EMIC waves associated with fast magnetosonic shocks in the magnetosphere and in the solar wind. In the magnetosphere, these shocks can be associated with either dynamic pressure enhancement or shocks in the solar wind and can lead to the formation of a “bunch” distribution of O+ ions in the perpendicular velocity phase space. The O+ bunch distribution can excite strong He+ EMIC waves and weak O+ and H+ waves. The dominant He+ EMIC waves are strong in quasi-perpendicular propagation and show harmonics in frequency spectrum of Fourier analysis. Further analysis by using Hilbert-Huang transform shows that these signals are similar to Duffing oscillations and exhibit frequency modulation in the instantaneous frequency spectrum. The proposed mechanism can explain the generation and some observed properties of He+ and O+ EMIC waves in the magnetosphere.
Strong fast magnetosonic shocks are often observed in the solar wind. In the shock downstream, the hydrogen and helium ions are strongly heated to achieve high ion beta and high temperature anisotropy. These conditions can lead to efficient generation of EMIC waves and mirror mode waves in the downstream, which are often identified in satellite observations in the solar wind. We find that the EMIC waves are generated both in the parallel and quasi-perpendicular directions. The parallel EMIC waves have been widely studied theoretically and observationally, while the excitation of quasi-perpendicular EMIC waves is usually overlooked. We also find coalescence of mirror waves as they drift with the plasma to further downstream.
| 附件: 20180322 李昆翰博士.pdf