Title: Theoretical Foundation Behind Strong Growth of Smartphones

Speaker: 黃正能 / 華盛頓大學電機系教授

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• Qualcomm's Awareness
• AT&T's Digital Home/Life
• Wearable Computing and Bendable Display
  • Google glass - 華大教授三、四年前被 google 挖角過去做的東西
  • Samsung bendable display
• Apple TV AirPlay and Google Chromecast
  • display device 不需要永遠都在 mobile device 上
  • google chromecast USD$35.00
• Transparent Smart Windows

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What are Theoretical Foundations behind these technology?

Energy Efficient + CPU, GPU

SoC Based Powerful Engine

Qualcomm SnapDragon 600

CPU + GPU

根據不同狀況使用 CPU 或 GPU

Power Efficient Design

• 省電
• Thermal Design Power
• Leakage 的耗電越來越大

Run-Time System-Level Energy Self-Optimization

• Optimization - 控管 Device 內的各個 chip

Standarlize

Audio

Human Psychoacoustics

• Hearing Sensitivity - 只聽得到對 20~20000 Hz 的頻率
• Frequency Masking - 某個頻率的聲音特別明顯的時候，會聽不到這段時間其他頻率的聲音
  • Saving More Bits with Frequency Masking
• Temporal Masking - 某段時間音量特別大的話，會聽不到在這段時間前後的其他聲音

利用上述這三點作為音頻壓縮技術的基礎

Audio Coding Standards

• MP3 (128Kbps)
• AC3
• AAC (64Kbps)
• HE-AAC (48 or 24 Kbps)

Video

Digital Video Coding

• Digitize
• Infra-frame compression (Simlliar to JPEG)
  • A DCT Based Intra-Frame Encoding
    • img -> DCT -> Quantize -> Zig-zag -> ...
  • Coding Block
  • Motion Vector Search - 拿 difference 去作 DCD 再作壓縮，省略掉重複的部份
• Symbol Entropy coding - 機率因素
• Rate Control

Video Coding Evolution

• MPEG-2 - 1994
• AVC/H.264 - 2003
• AVC Scalable Extension
• HEVC/H.265 - 2013
  H.265 用 50% 的 bitrate 壓縮出來的效果跟 H.264 100% bitrate 差不多

Multi- and Free-View of Video Scenes

• Users can dynamic select and viewpoint they want to use
• Virtual Viewpoint Not Captured by the real camera - 可以透過多個 Camera 模擬出實際上不是由真的 Camera 拍攝出來的視角

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What will be 5G?

1991 - Voice - SMS - 2G
2001 - App - SNS - 3G
2009 - Big Data - Cloud - 4G
2020 - ??? - ??? - 5G #沒記到- -"

Earlier Generations of Mobile Technologies

• 2G
• CDMA
• Hive technology

Toward ALL-IP 4G Wireless

• LTE (Long Term Evolution) of 3GPP
• WiMAX
• 4G

OFDM & OFDMA

Channel Quality Dependent Scheduling

MIMO (Multiple Input Multiple Output)

簡單來說，就是多支天線彼此之間的合作，讓收訊更好。

SD(Spatial Diversity) & SM(Spatial Multiplexing)

Coordinated MIMO

甚至使用不同的基地台讓收訊更好

Adaptive Modulation & Coding (AMC)

加入調變或 error correction code 讓收訊的效果更好

QoS(Quality of Service) and QoE(Quality of Experience)

• Packet lost

Scheduling and Resource Allocation

透過安排，讓收訊品質更好

Heterogeneous Wireless Networks

透過一些小裝置合作，達到更好的無線收訊品質

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Secured and Right Protected Usage

Digital Right Management (DRM)

• DRM License Server - 認證

What is Encryption

• Symmetric encryption (secret key cryptography)
• Asymmetric encryption (public key cryptography) - 為了要傳送 secret key

Secret Key

• DES - IBM
• AES - NIST
• Fast and efficient
• to use public key cryptography only to a private secret key

Public Key

• RSA (明天要考密碼學期中考 還只能用手算 現在看到這個真的超親切的啊)

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Conclusion

• Smartphones will evolve to all kinds of wearable devices, sensors, attached to our bodies (wireless chargeable), and displays are avaailable anywhere surrounding us.
• HCIs(speech, gesture, facial, etc) will replace keypads
• Internet of things(IoTs) will be all ubiquitous in our living environment
• Information are collectd, indexed, and available in/from clouds

作 low power 技術的教授都被 Google 挖走了XDD

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Academic Research: It is Easier Than You Think

Important Features (M2I4) You should have

如果你想唸研究所的話，希望你有以下的特質
+ Motivation: really enjoy digging deeper into the scientific truth
+ Maturity: never afraid of being failed or left alone
+ Innovation: always think of what is (or can be) new and different?
+ Intelligence: filter useful information to become usable knowledge
+ Independence: a step-by-step problem formulation and module solving
+ Integrity: always be honest in reporting and research

Getting Ready for Research

• Research topics selection and switching
  • Extend from senior graduate students' topics
  • Existing research projects in the Lab
  • Something your advisor is willing to learn closely with you
• Depth knowledge
  • A good series of class taking, or self study related tutorial background
  • Most updated Conference/Journal papers (IEEE Xplore)
  • Joint project discussions and group collaborations, or new class offering
• Breadth Knowledge
  • Attend technical presentation and active questioning (key messages?)
  • Magazine and Hi-Tech News
  • 到最後很多領域會殊途同歸，都會彼此相關，所以有機會的話可以瞭解一下其他領域在做什麼，尤其是一些 Conference。
  • 透過瞭解其他領域的新聞及期刊，可以瞭解到整個市場的趨勢。
  • 研究生有人去面試的時候，被問到的問題剛好是他在聽同學的 group meeting 時聽到的。

Jumping into Research

• Extensive literature survey and problem formulation
• Summarize others' paper in their block diagrams (flow charts) - look for weak links or not convincing blocks
  • 看完別人的 paper 以後，要有辦法自己畫出剛剛那篇 paper 的 block diagram ，如果畫不出來的話，代表你還不夠瞭解那篇論文在幹嘛。
• Conclusion meet the original problem formulation?
• Methodologies: integration -> evolution -> revolution
• Always use the data and compare the results with the most recent or best reported results
• Clear and detailed interpretation of simulation results
  • 做完 simulation 以後，要把結果好好想清楚，再跟自己的 leader 討論，而不是把整個 simulation 的結果原封不動的丟出來。
• Confidence and leadership building (organized speech in group or individual meetings)
  • 出去就業後不該是只幫別人寫程式碼，而是應該當個 leader ，因為研究給你訓練就是如此。得到一個新的題目、開始 survey、嘗試、失敗，這是你已經學到的東西，所以你應該已經瞭解如何處理，所以你應該當個 leader。

Persistence in Research

• Never expect a smooth path, refine the research scopes all the time (backoff slightly to find brighter road ahead)
• Learn from any failure
• Never hide from your professor

Research Publications and Technical Reports

• Practice Engilish writing of thesis and papers: practice by mimicking
• Always seek publication opportunities: from conferences to periodical journals
  • 自己主動去找有什麼地方可以投稿。
• Learn the standard writing style and outline of manuscript (a good outline, 70% done!)
  • 能夠把自己大綱全部列出來，並且瞭解大綱在做什麼，這樣大概就完成百分之七十了。
• Learn from the grammatical errors corrected by your advisor or technical editing persons.
  • 寫論文的文法很重要，設法知道老師幫你改了哪些部分，並從中學習。
• Discuss clearly the flow charts and simulation results in your papers, never leave the weak links
• Never be afraid/frustrated of major/minor revision of paper submission - reviewers are never your enemies
  • 別人有什麼意見的話要用心傾聽，如果有好的意見的話就記得要更改。