Our research focuses on decentralized network optimization and its applications. This is a world of networks. Various networks around us are collecting data and processing data; examples include wireless sensor and actuator networks, vehicular ad hoc networks, autonomous robot networks, mobile device networks, distributed or decentralized computing networks, etc. Within these networks, nodes are subject to limited energy, communication, and computation resources. There are often no fusion centers to coordinate actions of the nodes. With the aid of optimization tools, we devote to design and analyze efficient network data processing algorithms that are faithful to the resource-limited and decentralized natures of the networks.