Chang Han Yuan

GitHub Pages Medium

Taipei City, Taiwan

Work Experience

Apr 2021 - Present
Taipei, Taiwan

1.Implement Gitlab for version control.
- Solving the conflict with two different developing line from Shenzhen and Taiwan.
2.Migration from a 16 years live web based Loan Management System (LMS) to an 8 years live winform based LMS.
- Writing T-SQL to do the migration. Total migration downtime is around 40 mins.
3.The 16 years LMS is mainly for the mortgage loan, 8 years LMS is mainly for the personal loan.
- Plantext key-in resolve. Data sorting and classification.
- Dirty storage data cleaning.
- Solving duplicate data in both live system.
- Solving architecture differently. There are completely different repayment calculation work-flow.
- NO Normalization - UNF level & 1NF level.
- Parameter mapping.
4.Rewrite T-SQL to mitigate an SOP of upload client's credit to the credit agency.
- From over 60 steps, including multiple times excel marco handling and manual changing SQL server SP, this usually need to spend at least 1 day full time job IT to do this SOP every month, to 2 T-SQL script and 1 SQL-Agent corn job, within 10 seconds to finished the job.
5.Writing an dynamic SQL to generate dynamic year on an .RDLC report.
6.Successfully finished data migration project along within 1 year.
7.Updating the application from .Net framework 2.0 to .Net framework 4.7, due to the need of implement Anti-Money Laundering by using the RestSharp package.

Sep 2018 - Apr 2021
Taipei, Taiwan

1.Providing the Investment Management System to the Invest Company.
- Successful go live in 6 months.
- Technical support for a responsible project for at least 1 year.
2.Building new modules for 4 major investment processes.
- Established fund loss-audit process.
- Modify old foreign exchange investment form with better UX.
- Repair unusable leave system.
3.Refactored inefficient legacy code.
- Refactoring module for further extension.
- SQL performance tuning.
- Improved waiting time from 12 second to 1 second.
4.Established complicated business logic of cash-flow into an easy to understand excel report.
- Using MSSQL function and stored procedure to achieve.
5.Teaching new colleague.
6.Data transferring by using our own developed ETL tool.
7.Write SQL SP to run the daily accounting process.
8.Solving weakness scan issue.

Graduate Institute of Astronomy

Sep 2016 - Sep 2017
Taoyuan, Taiwan

1.Established a pipeline to analyze data from space telescope databases.
2.Using running median method to fitting the light curve activities from solar-like star and smaller stellar.
3.Substract the raw light curve and fitted light curve to get pure solar flare events.
4.Summaris and comparing different physics of stellar and using the power law to compare with our sun.
5.Published a journal paper.

International Cooperation Group

Jul 2012 - Jun 2013
Taipei, Taiwan

GPA: 3.79 / 4.0 ; Class rank: 2/10
Relevant Coursework: Data analysis, Stellar physics, Galaxy physics, Planetary Science
Honor: Excellent work of PSROC in astronomy

Sep 2013 - June 2016

Sep 2008 - Jan 2012

Chang et al. 2017. LAMOST Observations of Flaring M Dwarfs in the Kepler Field. The Astrophysical Journal, Volume 834, Issue 1, article id. 92, 7 pp. (2017).

C#
- Basic Knowledge of OOP concept
- Winform CRUD
- Refactoring legacy code
- Improving performance
MS SQL
- Basic knowledge of SQL
- Refactoring legacy SQL functions and stored procedure
- SQL performance tuning, by reducing unnecessary sub-queries and adding index
- Customer service, providing readable SQL queries for solving online problems
Git
- Basic knowledge of git operations
- Responsible for finalizing the release branch (solving conflict)
- Cherry-picking the commit from different project
Python
- Established a pipeline to analyze data from space telescope databases.
- Using the running median method to fit things.
Matlab, PHP, C++
- Learned in University.