Yeongkwun Kim

Learn More
Vehicular Ad hoc Network (VANET) has become an attractive topic in fields of academia and industry due to its potential role in helping to improve traffic management and safety on the road. The information transmitted over a vehicular network is sensitive and can affect important safety decisions. However, they face various types of security attacks, such(More)
This paper proposes a SESAME, which is a Space-Efficient Stack Allocation MEchanism for multi-threaded sensor operating systems. It adaptively adjusts the stack size by allocating or releasing additional stack frame based on the amount of each function's stack usage information. Our experimental results show that the SESAME significantly minimizes spatial(More)
Vehicular ad-hoc networks (VANETs) have become the focus of much discussion due to its potential role in helping to improve traffic management and safety and enable a wide range of value-added services such as collision warning/avoidance and work zone warning. Because information transmitted over a vehicular network is sensitive and can affect important(More)
Concept maps are useful tools for representing general knowledge in order to organize and communicate information but they are difficult and tedious to build by hand. In this paper, we describe a system to help automate the knowledge acquisition process by using user-initiated automatic concept map generation. Our system can also display any part of the(More)
Information transmitted over a vehicular network may be sensitive and affect important safety decisions. Exchanging information must be based on trust; however, an issue that arises is the degree to which drivers can trust the received information from other (previously unknown) drivers. Thus, trust management is a fundamental and critical issue in(More)
Flooding has been used in mobile ad-hoc networks (MANETs) because it is the simplest method for broadcasting messages over the entire networks. Several reliable and energy-efficient flooding mechanisms were developed in recent years. However, they still have some trade-offs between transmission reliability and energy-efficiency in the flooding messages. In(More)
We present VPSI, which is a Virtual Protocol Stack Interface for wireless network simulators. VPSI provides two features; 1) a unified programming interface for developing network protocols, and 2) separation of simulator engine and the network protocols. By using VPSI, developers do not need to understand multiple different simulator engines. We(More)
In this paper, we propose <i>Arbiter-Recall</i>, which is a new kind of function code update management. When a function requires updating, <i>Arbiter-Recall</i> adaptively selects an energy-efficient method, deciding between a remote-call and a local-call after updating a function. The run-time decision is made by analyzing the cost of a remote-call, and a(More)
This paper proposes <i>PreeMe</i>, which is a preemptive realtime task management scheme for event-driven sensor operating systems. By efficiently allocating independent stack space for each task, <i>PreeMe</i> enables the preemptive task management for the event-driven systems. The size of the minimal stack space for each task is determined at compiletime,(More)