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The baseline information of density, distribution pattern of seabird community, and seabird-fishery interactions in the oceans are still relatively rare in China. From November 2013 to January 2014, we utilized line-transect method to investigate the bird community and fishery vessel in Beihai and Shatian, northern Beibu Gulf, China, for obtaining the baseline knowledge. The best model generated the seabirds’ density of 11.47 (95% confidence interval 6.90-19.05) individuals/km² and 1.94 (1.27 - 2.95) individuals/km2, respectively in Beihai and Shatian. The coefficient of variation value of 20.42% and 25.43% showed moderate accuracy. The Beihai and Shatian seabird communities had similar fixed kernel home range. Seabirds’ distribution largely overlapped with various vessels’ concentrated area, possibly due to abundant local fishery resources and forging behavior of seabirds. The MaxEnt model with the area under receiver operating curve (AUC) value of 0.957 for training data and 0.935 for test data showed reliable and accurate prediction. The distance to coast (64.7% contribution) and bathymetry (30.7% contribution) were the major variables. The model predicted extensive suitable coastal habitat of seabirds in northern Beibu Gulf. The present study provided valuable baseline information and a new perspective in protecting and monitoring seabirds. [ABSTRACT FROM AUTHOR]

Although oxide thin-film transistors (TFTs) have drawn great interests in flexible displays, a key obstacle is the requirement of high-temperature annealing to realized mobility >10 cm²/V · s. In this paper, a fully room-temperature strategy, involving the deposition of ~10 nm In-Ga-Zn-O (IGZO) channel layer and ~4 nmAl2O3 passivation layer, is introduced. The as-prepared flexible TFT on polymide substrate exhibits a saturation mobility of 15.3 cm²/V · s, Vth of 3.08 V, and on/off current ratio of 2.3 x 107. Thickness-dependent analysis indicates that the interface between Al2O3 and IGZO is composed of negative O-rich layer, which impel the energy band bending inside the IGZO layers and release of electrons from traps. This paper opens up a route to achieve fully room-temperature fabrication of high-performance flexible TFT. [ABSTRACT FROM AUTHOR]

With the prevalence of low-power wireless devices in industrial applications, concerns about timeliness and reliability are bound to continue despite the best efforts of researchers to design Industrial Wireless Sensor Networks (IWSNs) to improve the performance of monitoring and control systems. As mobile devices have a major role to play in industrial production, IWSNs should support mobility. However, research on mobile IWSNs and practical tests have been limited due to the complicated resource scheduling and rescheduling compared with traditional wireless sensor networks. This paper proposes an effective mechanism to guarantee the performance of handoff, including a mobility-aware scheme, temporary connection and quick registration. The main contribution of this paper is that the proposed mechanism is implemented not only in our testbed but in a real industrial environment. The results indicate that our mechanism not only improves the accuracy of handoff triggering, but also solves the problem of ping-pong effect during handoff. Compared with the WirelessHART standard and the RSSI-based approach, our mechanism facilitates real-time communication while being more reliable, which can help end-to-end packet delivery remain an average of 98.5% in the scenario of mobile IWSNs. [ABSTRACT FROM AUTHOR]

As an important component of the intelligent transportation system, internet-of-vehicles technology has attracted considerable attention. The dissemination of event-driven emergency messages with high reliability and low delay is vital to ensure traffic safety and improve traffic efficiency in urban environment. In this study, the authors propose a reliable emergency message dissemination protocol taking into account the urban road characteristics and scalability requirements, which consists of a layout-aware ready-to-broadcast-emergency-message and clear-to-broadcast-emergency-message handshake mechanism and a redundant relay node adaptation mechanism. Finally, the simulation results confirm the feasibility and effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

Thermal annealing is a conventional and effective way to improve the bias stress stability of oxide thin film transistors (TFT) on solid substrates. However, it is still a challenge for enhancing the bias stress stability of oxide TFTs on flexible substrates by high-temperature post-treatment due to the thermal sensitivity of flexible substrates. Here, a room temperature strategy is presented towards enhanced performance and bias stability of oxide TFTs by intentionally engineering a sandwich structure channel layer consisting of a superlattice with aluminum doped zinc oxide (AZO) and Al2O3 thin films. The Al2O3/AZO/Al2O3-TFTs not only exhibit a saturation mobility of 9.27 cm2V-1 s-1 and a linear mobility of 11.38 cm2V-1 s-1 but also demonstrate a better bias stress stability than AZO/Al2O3-TFT. Moreover, the underlying mechanism of this enhanced electrical performance of TFTs with a sandwich structure channel layer is that the bottom Al2O3 thin films can obviously improve the crystalline phase of AZO films while decreasing electrical trapping centers and adsorption sites for undesirable molecules such as water and oxygen. [ABSTRACT FROM AUTHOR]

The effect of intrinsic stress on the structure and physical properties of silicon-tin-oxide (STO) films have been investigated. Since a state of tensile stress is available in as-deposited films, the value of stress can be exponentially enhanced when the annealing temperature is increased. The tensile stress is able to not only suppress the crystallization and widen the optical band gap of STO films, but also reduce defects of STO films. In this report, the good electrical performance of STO thin-film transistors (TFTs) can be obtained when annealing temperature is 450 °C. This includes a value of saturation mobility that can be reached at 6.7 cm2/Vs, a ratio of Ion/Ioff as 7.34 × 107, a steep sub-threshold swing at 0.625 V/decade, and a low trap density of 7.96 × 1011 eV-1.cm-2, respectively. [ABSTRACT FROM AUTHOR]

With the advancement of computing and network virtualization technology, the networking research community shows great interest in network emulation. Compared with network simulation, network emulation can provide more relevant and comprehensive details. In this paper, EmuStack, a large-scale real-time emulation platform for Delay Tolerant Network (DTN), is proposed. EmuStack aims at empowering network emulation to become as simple as network simulation. Based on OpenStack, distributed synchronous emulation modules are developed to enable EmuStack to implement synchronous and dynamic, precise, and real-time network emulation. Meanwhile, the lightweight approach of using Docker container technology and network namespaces allows EmuStack to support a (up to hundreds of nodes) large-scale topology with only several physical nodes. In addition, EmuStack integrates the Linux Traffic Control (TC) tools with OpenStack for managing and emulating the virtual link characteristics which include variable bandwidth, delay, loss, jitter, reordering, and duplication. Finally, experiences with our initial implementation suggest the ability to run and debug experimental network protocol in real time. EmuStack environment would bring qualitative change in network research works. [ABSTRACT FROM AUTHOR]

Recently there has been a new emerging trend in integrating Named Data Networking (NDN) and wireless sensor networks (WSNs) together to implement real data-centric Internet of Things (IoT). However, the main solutions in current literature lack energy efficient design to meet the severely limited energy resources in WSNs. In this paper, we propose a dual mode Interest forwarding scheme (called DMIF in short) for NDN-based WSNs. The DMIF consists of two combined forwarding modes, in which several energy efficient mechanisms including flexible mode shift, flooding scope control, broadcast storm avoidance, packet suppression, and energy weight factors are designed to save and balance the energy consumption. We extend the ndnSIM to support wireless multihop communication to validate the proposed scheme. Simulation experiments show that the DMIF outperforms the baseline schemes in terms of total energy consumption, energy equilibrium rate, and network lifetime. [ABSTRACT FROM AUTHOR]

Internet of Things (IoT) has been booming with rapid increase of the various wearable devices, vehicle embedded devices, and so on, and providing the effective mobility management for these IoT devices becomes a challenge due to the different application scenarios as well as the limited energy and bandwidth. Recently, lots of researchers have focused on this topic and proposed several solutions based on the combination of IoT features and traditionalmobilitymanagement protocols, in whichmost of these schemes take the IoT devices as mobile networks and adopt theNEtworkMObility (NEMO) and its variants to provide themobility support. However, these solutions are in face of the heavy signaling cost problem. Since IoT devices are generally combined to realize the complex functions, these devices may have similar movement behaviors. Clearly analyzing these characters and using them in the mobility management will reduce the signaling cost and improve the scalability. Motivated by this, we propose a PMIPv6-based group binding update method. In particular, we describe its group creation procedure, analyze its impact on the mobility management, and derive its reduction ratio in terms of signaling cost. The final results show that the introduction of group binding update can remarkably reduce the signaling cost. [ABSTRACT FROM AUTHOR]