Welcome to Kokeb

Our expertise is in developing low cost engineering and scientific applications using the wealth of publicly available models, algorithms, open source software libraries for Microsoft and Android platforms. We do all the research needed in consultation with our customers to incorporate both in-house and state of the art algorithms and models available in the open literature. An example of our recent work and research in applying Dantzig’s seminal workforce scheduling model to call centers is shown below. We also offer an in-depth 3 day hands-on training course on Dantzig’s workforce scheduling model based on the contents of the book and extensions to other applications.

Our Latest Publication

A practical book for call center analysts to implement Dantzig’s seminal workforce scheduling model to generate, evaluate, and optimize service level performance of weekly agent schedules using Excel 2007, C#.NET components and publicly available solvers, algorithms, and hardware.

Book features:

– Introduction to Dantzig’s seminal workforce scheduling model: Minimize CTX subject to AX >= B, X >= 0. Formulation of tour (A), requirement (B), and objective (C) matrices for weekly tour scheduling of agents.
– Model solution using public solvers (GLPK, lp_solve, COIN-OR Cbc) on local hardware and in the cloud (using NEOS Feasibility Pump and SCIP) on public hardware.

– Generating a schedule with an upper bound on total number of weekly tours, each tour having lower and upper bounds on number of agents using auxiliary binary (on-off) decision variables. C# code snippets to create console and Excel 2007/VSTO applications in Microsoft Visual Studio 2005/2010

Monte Carlo stochastic simulation to estimate schedule service level and ASA. Effects of controllable parameters on schedule quality.

– Near optimal scheduling to meet a target service level for a given call load. Adjust SIPP (Erlang-C) requirement for period dependence to dampen “roller coaster” ride in service level performance.

– A novel frequency domain reformulation of Dantzig’s time domain model to reduce size by 75% by retaining only low frequency Fourier components of the requirement (B) and tour (A) vectors.

 Our Latest Research

Modifying traditional SIPP  (ErlangC) requirement in Dantzig’s model using stochastic simulation to minimize “roller coaster” ride of schedule service levels in a call center

Frequency domain and convolution formulations of Dantzig’s time domain model