Stephan Wehner

Objective

Exciting and rewarding challenges for my software design and development expertise and my analytical skills.

Skills and Qualifications

Internet Technologies:

Ruby on Rails, J2EE, EJB, JMS, JSP, Servlets, Tomcat, BEA Weblogic Server, Apache Webserver, CGI Programming, HTML, XML, XSLT, djbdns, qmail.

Database Systems:

Oracle 8g,9i, mysql.

OO Modelling and Design:

Rational Rose, UML.

Graphical User Interfaces, 2D and 3D Graphics:

Java Swing, MFC, SGI, svgalib, Postscript, gnuplot.

Operating Systems:

Unix (Solaris, FreeBSD, Linux), Windows 95, 98, 2000, NT.

Programming Languages:

Ruby, Java (Sun Certified Programmer & Developer for Java 2, RMI, JNI), Javascript, C, C++, Visual C++, Visual Basic, Perl, Matlab, Maple, octave, mupad, Assembler.

Development and Other Tools:

JBuilder, Eclipse, Makefiles, lex, yacc, sed, awk, Unix shell scripting, cygwin

Computational Mathematics:

Time-dependent partial differential equations, scheduling, sparse linear systems, search heuristics, valuation of financial derivative instruments.

Selected Professional Experience

• Consultant, The Buckmaster Institute, Inc. for E-xact Transactions Ltd., Vancouver (2006 - present)
  

  Web based credit card transactions: reporting, managing batches, collecting online payments. PCI compliant; Ruby on Rails.

• Team Lead & Analyst, SITA INC Canada, Inc., Vancouver (2001 - 2006)
  

  The Vancouver office of SITA produces a range of software products for fare management within the airline industry. I was responsible for WebLogic/Oracle/Swing based 3-tier J2EE applications and MQSeries systems for importing external feeds. Full product life-cycle, from functional specification, implementation and unit testing/QA, to production deployment and support. Code refactoring. HTTP servlets to synchronize databases via XML. Mentoring of junior developers.

• Senior Analyst & Software Developer, Applied Financial Technology, San Francisco (2000 - 2001)
  

  Applied Financial Technology offers a suite of mortgage prepayments and option pricing models to the financial industry. As part of the software team, I improved the existing core (C++) libraries. I created a state-of-the-art computation server based on Java Swing, RMI and JNI including a graphical user interface. Ported AFT's Windows/Solaris based libraries to the Linux platform.

• Internet Consultant, Advertain.com, Vancouver & MITACS, Vancouver, (1999-2000)
  
  • Advertain.com is a portal which connects users with advertisers promotional internet games. I developed advertain.com's user tracking management system and the online voting facility. I wrote the Perl CGI scripts and SQL database interface.
  • MITACS is the Canadian Centre of Excellence in the mathematical sciences. I created the website for the MITACS 2000 Annual General Meeting from content delivered by MITACS headquarters. I designed the necessary graphics and wrote CGI scripts for attendee's registration.
• Optimization Consultant & Developer, School of Computing Science, Simon Fraser University, Burnaby, (1996-1997, 1999-2000)
  
  • The Optimization Group of the School of Computing Science provides the Vancouver International Film Festival with a scheduling system. I developed scheduling algorithms to generate the midday schedules and to be able to quickly perform last-minute changes to the schedule. I implemented these in Visual C++ and created a user-friendly interface in Visual Basic.
  • The School of Computing Science also collaborates with Stemsoft Software. Stemsoft is interested in providing a scheduling system for health facilities staff. I delivered Functional Analysis and Project Analysis documents. I developed a scheduling algorithm and implemented the search heuristics in C++.
• Mathematical Software Developer, Centre for Experimental and Constructive Mathematics, Simon Fraser University, Burnaby & Department of Chemistry , University of British Columbia, Vancouver, (1996, 1997 - 1999)
  
  • The CECM is a mathematical research centre which heavily uses modern computer resources. I designed a method to estimate the run-time of a procedure symbolically in terms of its numerical parameters and implemented it in the programming language Maple for Maple procedures. I wrote basic parser functions for translating Maple programs into C and FORTRAN. I improved a graphical user interface for SGI workstations based on the Forms and XForms libraries (in C) and adapted it to the WWW (using CGI scripts)
  • Prof. Lionel Harrison works extensively on biological growth processes. One of his ambitions is to develop a 3D mathematical model for the growth of Micrasterias algae. He completed work on the 2D model. For the 3D case I devised and implemented a numerical method for solving reaction-diffusion equations on arbitrary surfaces (in C). I refined earlier methods to model surface growth, and wrote customized 2D and 3D-display routines for producing images in Postscript and on a Silicon Graphics workstation.
• Embedded Software Engineer Gesellschaft fur Automation und Datentechnik (GAD), Heidelberg, Germany & Embedded Spaces Inc., Vancouver (1991, 1997)
  

  Both GAD and Embedded Spaces specialize in embedded systems and software development.

  • I developed an emulation of an IBM 3279 terminal in collaboration with the hardware team. I programmed the interface with a UART M68652 MPCC in 68000-Assembler and the higher levels of the communication protocol in C.
  • I implemented, according to Embedded Spaces' specifications and coding standard, low-level data access functions for a real-time database application, and a parser for translating database definition files into internal representation from which C-code is generated. (All programs in C)

Education

• Ph.D. 1995, Department of Mathematics and Statistics, Simon Fraser University, Burnaby, Canada
• Diplom (equiv, M.Sc.) 1991, Department of Computing Science, Universitat Karlsruhe (TH), Karlsruhe, Germany
• Vordiplom (equiv, B.Sc.) 1988, Department of Computing Science, Universitat Karlsruhe (TH), Karlsruhe, Germany

Selected Publications

• Enumerations, Countable Structures and Turing Degrees, Proceedings of the American Mathematical Society, July 1998.
• On recursive enumerability with finite repetitions, Journal of Symbolic Logic, Volume 64, Number 3, 1999.
• www.thrackle.org, a website dedicated to John Conway's famous Thrackle Problem.
• Traffic Life: Passionate Tales and Exit Strategies, Vancouver, 2004. A book about/against car culture.

Involvement in Community Projects

• East-End Food Coop, Vancouver, 1999-present, Director, Finance Committee Chair, Internet Committee Chair.
• CCEC Credit Union, Vancouver, 1999-2000, Credit Committee Member

References - available on request.