Bing-Hong Liu

Learn More
Wireless sensor networks have often been used to monitor and report the locations of moving objects. Since sensors can also be used for storage, a wireless sensor network can be considered a distributed database, enabling us to update and query the location information of moving objects. Many researchers have studied the problem of how to construct(More)
This paper proves that deploying sensors on grid points to construct a wireless sensor network that fully covers critical grids using minimum sensors (Critical-Grid Coverage Problem) and that fully covers a maximum total weight of grids using a given number of sensors (Weighted-Grid Coverage Problem) are each NP-Complete. Keywords-NP-Complete, wireless(More)
A wireless sensor network has unidirectional links because sensors can have different transmission ranges, sensors have unstable transmission ranges, and a hidden terminal problem exists. In this paper, we introduce a virtual coordinate assignment protocol (ABVCap_Uni) to assign virtual coordinates to nodes that have no geographic information in wireless(More)
In this paper, we first propose a method, ABVCap, to construct a virtual coordinate system in a wireless sensor network. ABVCap assigns each node multiple 5-tuple virtual coordinates. Subsequently, we introduce a protocol, ABVCap routing, to route packets based on the ABVCap virtual coordinate system. ABVCap routing guarantees packet delivery without the(More)
A new kind of surface plasmon resonance (SPR) sensor based on silver-coated hollow fiber (HF) structure for the detection of liquids with high refractive index (RI) is presented. Liquid sensed medium with high RI is filled in the hollow core of the HF and its RI can be detected by measuring the transmission spectra of the HF SPR sensor. The designed sensors(More)
Recently, sweep coverage, which is the problem of scheduling mobile sensors to periodically visit a certain number of points of interests (POIs) such that the number of mobile sensors is minimized and each of POIs can be visited periodically within a given time period, has received a great deal of attention in the wireless sensor networks. Many methods have(More)
In the tracking system, a better prediction model can significantly reduce power consumption in a wireless sensor network because fewer redundant sensors will be activated to keep monitoring the object. The Gauss-Markov mobility model is one of the best mobility models to describe object trajectory because it can capture the correlation of object velocity(More)
A long-range surface plasmon resonance (LRSPR) sensor based on dielectric/silver-coated hollow fiber (HF) is proposed. It can detect the refractive index (RI) of sensed liquid filled in the hollow core of the sensor. A HF LRSPR sensor with 90-nm-thick silver layer and 260-nm-thick OC300 layer is fabricated. Experiments are taken to evaluate the performance(More)
Wireless sensor networks are formed by connected sensors that each have the ability to collect, process, and store environmental information as well as communicate with others via inter-sensor wireless communication. These characteristics allow wireless sensor networks to be used in a wide range of applications. In many applications, such as environmental(More)