學術演講


<專題討論>2018/11/15(四)14:10綜合大樓2樓48218教室演講 : 李芳承 博士(國家實驗研究院台灣海洋科技研究中心)

張貼者:2018年11月10日 下午5:24Dabby Lu

講題 : 前進水波槽實驗分析與模擬應用
摘要 : 1.利用雷射光學量測配合高速攝影技術系統拍攝一系列前進波影像,再利用影像處理技巧進行邊緣偵測,數位化、分析波浪連續自由液面高程。其中從全尺度拍攝中,成功地利用 LabVIEW 發展多斷面影像連結技術與邊緣偵測技術,藉由量測 Y 軸向的放大影像觀察所波浪通過結構物理特徵現象。數位化水面高程資料,再透過Matlab發展二維快速傅立葉轉換(2DFFT) 結合一維 Morlet 小波轉換(1DMWT)方法完整分解波浪訊號技術。
2.發展運算模擬平台,以無網格(SPH)數值模式探討水波槽問題(多相流)。

<專題討論>2018/11/8(四)14:10綜合大樓2樓48218教室演講 : 江致宇 博士候選人(成功大學電漿所)

張貼者:2018年11月2日 上午1:10Dabby Lu   [ Ann-Chen Jang 已於 更新 ]

講題:Big Data in Space Sciences
摘要:經過數十年來的探索,太空已不再是人類遙不可及的夢想之地,過去利用衛星觀測所累積的各種科學及工程的數據,不但掀開太空中神祕的面紗,一項項待解的太空科學議題也一一獲得驗證,人類對太空的認識已不再是之前瞎子摸象的時代,新的衛星任務目標都更加具體,然而接下來可能會有人想問,什麼是太空探索的下一步呢? 大家或許有注意到,這幾年全球掀起了太空熱,各種創新衛星、載具研發或甚至加值服務都不斷出籠,這一切的推手都可歸功於太空產業走向商業化的成果,而有了這樣好的立基點之後,加快了衛星研發的時程和發射升空的頻率,同時數據資料的累積也預期將以驚人的速度成長。因此,面對太空大數據時代的來臨,我們做好準備了嗎? 從過去到現在所留下的龐大數據資料,是否能進行更有效率的大數據應用與開發,為未來太空AI時代打下基礎呢? 本演講將以太空科學資料(電漿相關)的角度切入,進行介紹與分析,希望聽眾能對太空資料處理流程能有更進一步的認識。

<專題討論>2018/11/1(四)14:10綜合大樓2樓48218教室演講 : 詹寶珠 特聘教授(成功大學電機系)

張貼者:2018年10月28日 下午11:36Dabby Lu

講題:An Introduction to Deep Learning Network Models and their Applications
摘要:Deep learning neural networks have been the main focus in recent researches and applications. In this talk, we will give an introduction of the concept of neural networks and the deep learning models. A brief overview of the development of deep learning network models for image analysis and other applications will be provided. Some mechanisms in achieving successful training will also be discussed.

<專題討論>2018/10/25(四)14:10綜合大樓2樓48218教室演講 : Prof. Golubkov Gennady Valentinovich(Supervisor of the scientific subject “Chemical physics of Earth atmosphere” in the Semenov Institute of Chemical Physics of RAS (Moscow, Russia))

張貼者:2018年10月21日 下午7:12Dabby Lu

講題:Resonant quantum properties of the environment for GPS signal propagation
摘要:Uncontrollable sporadic distortions of satellite signals of global positioning system (GPS) caused by a phase failure and group-delays in a propagation of electromagnetic radiation through a medium take place in periods of high solar activity and geomagnetic disturbances formation in the Earth's ionosphere. Searching of ways ensuring a sustainability of the GPS system is a fundamental scientific and technical problem. Additional background incoherent ultra-high frequency (UHF) radiation is formed at the altitudes of E and D layers of the Earth ionosphere during these periods. Wavelengths of this radiation correspond to a range from a decimeter to a millimeter. This emission is due to transitions between Rydberg states of atoms and molecules which are excited by electrons in plasma, and are surrounded by a neutral particle environment. Reliable information about of UHF radiation flux power in this wavelength range is not currently available. The answer to this question depends entirely on knowledge of impact and radiation quenching of Rydberg states dynamics and the kinetics of their location in a lower ionosphere, i.e. on the quantum optical properties of a perturbed environment. Analysis of existing experimental data has shown that the UHF radiation is formed in the atmospheric layer located at altitudes of 80-110 km. A physical mechanism of the satellite signal delay is due to cascade resonant scattering of GPS signal photons in the decimeter range while passing through this layer over a set of Rydberg states. The most promising approach to studies of the medium optical quantum properties can be a simultaneous analysis of the background additional noise and the GPS signal propagation time delay which determines a positioning error. Using standard methods of noise measurement one cannot detect physical and chemical processes which are responsible for noise formation and errors affecting the positioning Therefore, the problem can be solved if the level of a background noise will be considered as a noise of the measured GPS signal, since propagation delays of the latter are due to one of the most important atmospheric collisional process, i.e. the orbital degeneracy of highly excited states. For this purpose, it is advisable to use the signal-to-noise ratio, where the signal corresponds to a level of a signal obtained by GPS receiver, and a noise corresponds to GPS signal fluctuations.
In this lection a theory current state is examined and ways of its further development are discussed. They are associated with the progress of theoretical methods for describing of the medium neutral particles impact effects on the dynamics of collision and radiation quenching focusing primarily on elementary processes involving molecules of nitrogen and oxygen. It is shown that preliminary calculations of non-adiabatic transitions dynamics between potential energy surfaces (PES) of Rydberg complexes, the construction of appropriate electronic wave functions, calculations of allowed transition dipole moments and also determination of emission line shapes are necessary for quantitative estimations of excited particles influence on a spectrum of incoherent UHF radiation of the atmosphere. These results should be included in the total kinetic scheme, which establishes dependence of UHF radiation on temperature and density of the lower ionosphere. Then the satellite monitoring data of infrared (IR) radiation, accompanying the UHF radiation, can be directly used for detection of Rydberg states and diagnostics of the plasma parameters.
The lecture is based on the materials of the review
Golubkov G.V., Golubkov M.G., Manzhelii M.I., Karpov I.V. Optical quantum properties of GPS signal propagation medium – D layer. In: The Atmosphere and Ionosphere: Elementary Processes, Monitoring, and Ball Lighting. Eds. Bychkov V.L., Golubkov G.V., Nikitin A.I. New York: Springer, 2014. P. 1-67.

<專題討論>2018/10/18(四)14:10綜合大樓2樓48218教室演講 : 談永頤 教授(成功大學電漿所)

張貼者:2018年10月11日 下午11:29Dabby Lu

講題:Parameters of magnetospheric locations associated with occurrences of aurora and comparison with their ionospheric counterparts
摘要:The Energization and Radiation in Geospace (ERG) satellite (nicknamed "Arase"), launched from the Uchinoura Space Center in December 2016, began its regular observations of the inner magnetosphere in March 2017. Among the various instruments aboard the Japanese satellite is the Low‐Energy Particle Experiments ‐ Electron Analyzer (LEP-e), developed by a Taiwanese team that featured members from Academia Sinica and National Cheng Kung University. The instrument measures electrons in the energy range between ~20 eV and 19 keV. As ERG's orbit covers the range of McIlwain L-parameter roughly from 2 to 9, overlapping with that of the auroral oval in the ionosphere, LEP-e is suitable for studying the magnetospheric origins of auroral electrons. In this study, we statistically compare the Auroral Electrojet (AE) index with LEP-e measurements as well as ERG data from the Medium-Energy Particle Experiments - Electron Analyzer (MEP-e). The correlation coefficients between the AE index and measurements at various electron energies enable us to identify the magnetic local times (MLT) together with L for the magnetospheric locations that are most often in association with occurrences of aurora. These parameters, MLT and L, are compared with those at ionospheric locations where auroral electron precipitation is statistically the dominant density-perturbation effect during disturbed times according to observations from another international collaborative satellite mission involving Taiwan, namely FORMOSAT-3/COSMIC.

<專題討論>2018/10/11(四)14:10綜合大樓2樓48218教室演講 : 陳炳志 所長(成功大學電漿所)

張貼者:2018年10月7日 下午7:46Dabby Lu

講題:大氣電學-地面與太空觀測 The atmospheric electricity - ground and space observations
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。

<專題討論>2018/10/4(四)14:10綜合大樓2樓48218教室演講 : 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)

張貼者:2018年9月30日 下午10:57Dabby Lu

講題:台灣半導體產業會被中國搶走嗎?
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。

<專題討論>2018/9/27(四)14:10綜合大樓2樓48218教室演講 : 林明發 教授(成功大學物理系)

張貼者:2018年9月21日 上午12:32Dabby Lu   [ 已更新 2018年9月21日 上午12:34 ]

講題:Single-particle and collective excitations in layered graphenes
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.

2018/7/17(二)14:10綜合大樓3樓48312教室演講 : 小山孝一郎教授(Asia Space Environment Research Consortium, Kanagawa, Japan)

張貼者:2018年7月16日 上午1:59Ann-Chen Jang   [ 已更新 2018年7月16日 上午2:15 ]

Road to Venus mission in Japan
- from curiosity to the realization-

K.-.I. Oyama
1.Institute of Space and Plasma Sciences, National Cheng Kung University, Tainan Taiwan.
2.International Center of Space Weather Study and Education Fukuoka, Japan
3.Asia Space Environment Research Consortium, Kanagawa, Japan

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.


<專題討論>2018/5/10(四)14:10綜合大樓2樓48218教室演講 : 龔慧貞 副教授(成功大學地科系)

張貼者:2018年5月6日 下午8:20Dabby Lu

講題:地球內部構造與地球磁場 Earth’s interior structure and geodynamo
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」。

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