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Algorithm, Blockchain, Coursera 真心推Coursera上的Data Structures and Algorithms Specialization, 挑有興趣的就好. 2017年底至今拿了4張Certifications, Algorithms on Graphs是比較有趣的課程. 其它3張是Algorithmic Toolbox, Data Structures, Algorithms on Strings Week14 (04/06) 讀書心得 Burrows-Wheeler Transform - data compression Cyclic rotation Sorting Last column Inverting Burrows-wheeler transform Mark the occurrence of characters Putting sorted bwt string to frist column Knuth–Morris–Pratt - string searching algorithm (or KMP algorithm) Suffix array - a sorted array of all suffixes of a string. Week15 (04/13) Week16 (04/20) Week17 (04/27) 網路文章 World’s first IOTA Smart Charging Station 哦哦哦！M2M. ...

Debug, Debug, Debug…, Muscle Up Tips Week9 (03/02) 讀書心得 FBI談判協商術 積極聆聽, 鏡像模仿, 極端錨點, 開放型/測試型/校準型問題, 對事不對人, 每個人都怕失去, 成見使人盲目, 假設提供指引. The power of “No”, Three types of “Yes”, The power of “Right”, Emotion is one of the keys, Be Honest. Thinking fast and slow. Week10 (03/09) 網路資源 Chris Voss: Never Split the Difference Week11 (03/16) 網路文章 Android Treble: blessing or trouble? Diving into SDCardFS: How Google’s FUSE Replacement Will Reduce I/O Overhead ...

Android, Chinese New Year, blockchain, Cache miss Week5 (02/02) 這個月雖然有年假但比平常更忙！ 結論: 放假不一定放鬆, 想專心做事 :-) 網路文章 Processor Pipeline Gallery of Processor Cache Effects Using Streamline to Guide Cache Optimization 參考這篇分析Kodi17.6影片播放時的L1/L2 cache access情況, 播放2160p影片時L1/L2 data ratios不高分別在0.046/0.18, 使用Kodi18更少分別為0.041/0.16. 另外Kodi18在記憶體使用上比17.6減少3.6%, cache miss 減少47~55%. Cache Refill Ratios算法 L1 data ratio: $CacheDataRefill/$CacheDataAccess L2 data ratio: $CacheL2DataRefill/$CacheL2DataAccess 網路資源 Blockchain Demo 大略的介紹blockchain, 簡單明瞭.

Android, Algorithms Week1 (01/05) 讀書心得 Algorithms on Graphs - Week5 給出座標上n個點: 找出最短路徑(the shortest path) 分群(Clustering) 為Minimun Spanning Tree相關問題, 可以使用Kruskal’s MST Algorithm 及Disjoint-set 來解. for all u ∈ V : MakeSet(v ) X ← empty set // a set with solution edges sort the edges E by weight for all {u, v } ∈ E in non-decreasing weight order: if Find(u) != Find(v): add {u, v } to X Union(u, v ) return X Week2 (01/12) 網路文章 Android编译系统中的Android.bp、Blueprint与Soong ...

SEAndroid, Algorithms, Numpy Android N -> O 被自己的石頭砸到腳 對於晶片廠來說Android決解了軟體開發的問題, 也加速了ODM/OEM的開發時程. 沒錯…但對於手機/電視之外的應用..存在些問題. 另外差異化及客制帶來些不定時炸彈. Sepolicy for Android Treble 使用numpy array修改pixel values. 網路資源 Machine Learning 101 - Jason Mayes New year’s resolutions IELTS overall 6.5 Data Structures and Algorithms Specialization Master of Computer Science in Data Science

A Note about sepolicy in Android Oreo. First thing first SELinux documents: SELinux for Android 8.0 What is SELinux? What is SEAndroid? SELinux Policy Concepts and Overview Android sepolicy files Policy path: /system/sepolicy BOARD_SEPOLICY_DIR (device/$VENDOR/$DEVICE/sepolicy/, device/$VENDOR/$DEVICE/common/sepolicy/) Policy Macros: system/sepolicy/public/te_macros system/sepolicy/public/global_macros system/sepolicy/public/ioctl_macros system/sepolicy/public/neverallow_macros system/sepolicy/private/mls_macros system/sepolicy/reqd_mask/mls_macros Security Context: file_contexts, labeling files infilesystem. property_contexts, labeling android system/vendor properties genfs_contexts, Pre-file labeling for /proc files, generic filesystem security contexts. seapp_contexts, used by zygote and installd via libselinux, mapping app UID andseinfofor /data/data directory hwservice_contexts, for hwservice manager to check vndservice_contestx, for vndservice manager to check service_contexts, for service manager to check Type Enforcement *.te Composing Policy for Android trebel Add domains for a service ...

SELinux, Arm Tech Symposia 2017 Taiwan, golang, IoT Week44 (11/03) 網路資源 Firmware Updates over Low-Power Wide Area Networks Enabling firmware updates over LPWAN ARMmbed/lorawan-fota-demo 滿有趣的問題, IoT建置會預期device要能長達10年的壽命, 但10年間的變化是很大的. Week45 (11/10) 網路文章 Android SELinux Treble Android O 為了加速產品開發, 在framework上有重大的改變, 使用了Treble. Vender, ODM, OEM有各自需要維護的partitions. Week46 (11/17) 網路文章 Neural fuzzing: applying DNN to software security testing 好奇其它的nural networks的應用, 常看到CNN. 網路資源 hacdias/filemanager 感覺不錯用的web filemanager, 目前很有活力, 送了一個PR不到1天就被merge了. 讀書心得 因為把玩hacdias/filemanager看了一下A Tour of Go在語法上還不太能適應, 不過還滿容易上手的, Method跟Interface的用法還要再研究一下, Concurrency也要花一點時間了解, 必竟concurrency是最大的賣點吧! 還有python使用上會有package dependency問題有點頭痛, golang編成binray的方式可以省掉這個麻煩, but 要如何方便的debug web front-end? 這可能要看一下go.rice. 但魚與熊掌仍不可兼得…package dependency, cross-platform, realtime debug. ...