  Project managers are continuously under pressure to shorten product
development durations. One practical approach for reducing the project duration
is lessening dependencies between different development components and teams.
However, most of the resource allocation strategies for lessening dependencies
place the implicit and simplistic assumption that the dependency structure
between components is static (i.e., does not change over time). This
assumption, however, does not necessarily hold true in all product development
projects. In this paper, we present an analytical framework for optimally
allocating resources to shorten the lead-time of product development projects
having a time-varying dependency structure. We build our theoretical framework
on a linear system model of product development processes, in which system
integration and local development teams exchange information asynchronously and
aperiodically. By utilizing a convexity result from the matrix theory, we show
that the optimal resource allocation can be efficiently found by solving a
convex optimization problem. We provide illustrative examples to demonstrate
the proposed framework. We also present boundary analyses based on major graph
models to provide managerial guidelines for improving empirical PD processes.
