Sigma Expert Solutions (SES) was founded and created by Demetrius Siachames in 2018 to provide solutions to complex and important engineering challenges. SES was founded on the principles that engineers that care about solving important problems will find a way to solve them.

Demetrius started his engineering career in the United States Navy and a Nuclear Propulsion Officer. He took that experience to the civilian world working for an engineering consulting firm, giving him broad exposure to different fields and opprotunities for varied engineering experience.

It has always been Demetrius’ ambition to create a company based on the reasons he chose to become an engineer when he was seven years old – to better understand the world around him, and leverage that understanding to improve our relationship to the world around us.

To learn more about Demetrius and his vision for SES, click below.


SES provides a wide range of services ranging from Project and Program Planning to Mechanical Designs. To see a full listing of engineering services, visit the services pages with the button below or through the menu.

Newsletter (e-blog)

An engineer’s perspective on a variety of topics. Every month brings something different, so check it out! The three latest topics are below, but all past newsletters can be accessed by clicking the Archive button.

Edition 16

Urban Mass Transit

Edition 15


Edition 14

Our Energy Future

Internal Design Work

SES performs ongoing internal design work as part of its mission to explore and understand a wide variety of topics and industries. Products of this internal work are published as either Design Studies, White Papers, or Inventions. Design Studies are summaries of areas being explored and developing concepts. White papers perform calculations or provide detailed design data for concepts to validate design concepts. Inventions consist of conceptual designs where a patent is being pursued for future business opportunities.

Explanation of Fields in the SMARRT form submission

Reference Scenario Inputs:

Number of People Infected – How many potential members of the gathering are infectious. The simulation starts when they enter (time=0).

Type of Activity – Impacts the number of particles spread as aerosols per respiration. More strenuous activities result in more viroid particles being released.

Air Changes per Hour – This is the air exchange rate with fresh air for the volume of air being breathed by the gathering. If you use forced air exchange, you can calculate the number of air changes per hour for your specific situation.

Space Floor Area and Ceiling Height – These are used to calculate the total space volume.

Duration Infectious Person is Present – This is how long the infectious person stays in the space after their initial entry. For the reference scenario, this defines the end of the simulation.

Gathering Scenario Inputs:

See the reference scenario for all inputs up to Time of space entry.

Time of space entry and exit – These values represent when you enter and leave the space referenced to the infectious person. For example, if you show up fifteen minutes late, but stay an hour after the end of a one hour party, the Duration Infectious Person is Present is 60 minutes, the Time of Space Entry 15 minutes, and the Time of Space Exit 120 minutes