Talk

The Common Spatial Data Infrastructure (CSDI) is a key initiative under the Smart City Blueprint for Hong Kong. The CSDI portal launched by the Development Bureau (DEVB) provides a map-based digital infrastructure as a one-stop platform to open and share spatial data. By allowing members of the public to search, view and download various kinds of spatial data from the portal, a wide range of possibilities for application development will be opened, the digital economy boosted and quality of life improved.

In 2022, I launched a Kotlin podcast show, Kotlin Fireside Chat, with my friends in Kotlin User Group. Now, we're taking things to the next level by building a podcast website with a statistical analysis dashboard. We've built a static website using Jamstack and connected it to a serverless API written in Kotlin. In order to aggregate the listener number across platforms, such as YouTube, BiliBili, Ximalaya, Lizhi, Qingting, we've also created a crawler to grab those numbers and display them in a custom dashboard.

I want to talk about some interesting cases and tips that I met when using Postgres in my daily job, which are topics general enough that most developer may also meet in their daily jobs (even for non-Postgres developers).

• Why LIMIT 1 is MUCH SLOWER than LIMIT 100?
• What's wrong with JSONB? (hint: it's TOO robust)
• Efficient query using LATERAL subquery (from 8s to 0.08s)

There are many different kinds of programming paradigm such as high-level coding and low-level coding. Verilog is another kind of paradigm, this talk will bring an introduction how coding in Verilog looks like and help audiences to jump start on it.

(廣東話) Programming 有幾種係人都feel到唔同嘅大，例如high level programming就同low level programming好唔同。而Verilog又係另一種好唔同嘅編程範式，希望係呢個talk為大家介紹同埋幫大家極速起手。

(書面語) Programming有兩大範式 : 高級語言(python/java)和底級語言(assembly), 而verilog是有別於以上兩大類的另一編程範式, 希望係此演講為大家介紹和令大家起步編寫verilog。

以用家身份分享利用開源操作系統（Google Chrome OS Flex) 及免費線上軟件/服務，在非政府機構(NGO)、學校、中小微企及初創企業(Start-up)等，如何達致節省開支並延緩電子垃圾產生。
亦會分享日常文書工作中使用開源工具（包括人工智能）小貼士。

In HKOSCon 2022, we discussed how Home Assistant could help to bridge the gaps between smart home products from different camps with local control in mind. We touch-based on the emerging yet promising Matter standard that hoped to resolve a lot of the interpretability challenges of different smart home ecosystems. One year on, products that comply with the Matter standard start to appear, and Home Assistant has also evolved to provide better support for Matter products.

Raspberry Pi already know well and many of you now using for your DIY hobbies and business. Do you are having fun playing with it/Is Raspberry Pi useful for your business? Masafumi will give a talk with a couple of use cases, demonstrate some of Raspberry Pi DIY gadgets and discuss what the use case is good to apply your DIY hobby/business projects.

This project demonstrates that multiple robots can collaborate to explore an unknown environment without GPS to generate a map with reasonable accuracy. This addresses exploration as a problem in the planning layer of the robotics domain. A frontier-based  exploration methodology will be explained. The main approach uses Rapidly-expanding Random Trees for frontier detection, and map merging for information sharing. The developed algorithm also makes use of existing solutions for SLAM, and path planning. The algorithm runs in a network of robots, and a master machine on ROS.

Unikernels are specialized operating system images that execute a single application. Through extreme specialization they can provide high performance, small memory footprints, fast boot times, and a reduced attack vector.

This talk will provide an overview of Unikraft (https://unikraft.org), a Linux Foundation project that provides a toolikit for creating highly specialized unikernels by combining a set of micro-libraries to tailor down the operating system strictly to the needs of the executing application.