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The age of the wireless network already advances to the fifth generation (5G) era. With software-defined networking (SDN) and network function virtualization (NFV), various scenarios can be implemented in the 5G network. Cloud computing, for example, is one of the important application scenarios for implementing SDN/NFV solutions. The emerging container technologies, such as Docker, can provide more agile service provisioning than virtual machines can do in cloud environments. It is a trend that virtual network functions (VNFs) tend to be deployed in the form of containers. The services provided by clouds can be formed by service function chaining (SFC) consisting of containerized VNFs. Nevertheless, the challenges and limitation regarding SFCs are reported in the literature. Various network services are bound to rely heavily on these novel technologies, however, the development of related technologies often emphasizes functions and ignores security issues. One noticeable issue is the SFC integrity. In brief, SFC integrity concerns whether the paths that traffic flows really pass by and the ones of service chains that are predefined are consistent. In order to examine SFC integrity in the cloud-native environment of 5G network, we propose a framework that can be integrated with NFV management and orchestration (MANO) in this work. The core of this framework is the anomaly detection mechanism for SFC integrity. The learning algorithm of our mechanism is based on extreme learning machine (ELM). The proposed mechanism is evaluated by its performance such as the accuracy of our ELM model. This paper concludes with discussions and future research work.

“Missing data” is an important research issue in big data analysis. This problem may cause data hard to analyze precisely. Inrecent research, several imputation-based methods have been proposed to solve the missing data issue without using domain knowledge.Among them, the missing data imputation method based on association rule mining was proposed to determine which value should be filled in the missing data. However, the generated rules may not always be suitable for filling in missing values. For example, some strong rules may fill up different missing values with the same result. We propose here an algorithm named RID (Rule-based Imputation with Distance function) to deal with this shortcoming. RID generates rules for missing data imputation by association rule mining andthen uses a distance function to adjust the rule to fill in values appropriately. Experimental results show that the accuracy of RIDis approximately 3 to 5 percentage higher than those of C4.5 and kNN, and approximately 6 to 7 percentage higher than that of HMiT.

Matrix multiplication is widely used in various applications of linear algebra. The efficiency of matrix multiplication in the MapReduce model is bounded by the workload of intermediate key-value pairs and transmission cost between the map phase and the reduce phase. An appropriate partition of matrix data can reduce unnecessary transmission cost of the two phases. A matrix decomposition based method is proposed in this paper to reduce the transmission cost and provides effective matrix multiplication computation. The experimental result shows that the proposed method can lower the transmission cost as the matrix size increases.

An adaptive radio frequency (RF) chain-antenna mapping mechanism is proposed for 5G millimeter-wave (mmWave) multiple-input multiple-output (MIMO) cloud radio access networks with the use of hybrid RF/baseband precoding design. To improve the achievable sum-rate (ASR) performance, a dynamic RF-antenna mapping technique, i.e., the MANHATTAN metric (MM) with/without overlapping strategy, is addressed in this paper. Simulation results show that an adaptive partially-connected architecture makes the ASR capacity approach to the fully-connected structure and decreases the requirements on computation and hardware complexities.

A highly sensitive, miniaturized, integrated optic refractive index sensor is proposed based on polarization rotation in waveguides. The sensitivity of the sensor can be increased by increasing the length of the waveguide rotator. Post-fabrication trimming technique can be used to adjust the detection range and eliminate the fabrication error of the device.

Convenience-related non-safety applications are interesting and enticing aspects of VANETs, with a number of public non-safety services such as Transit Signal Priority (TSP) and bus group communication systems (e.g. voice/video) expected to be developed for public transportation. In this paper, we design and implement a Transit Signal Control and Communication System (TSCCS) for use in real-life IEEE 802.11p/1609 On-Board Units (OBUs). As this TSCCS can reduce bus travel time and number of stops by employing a transit signal priority algorithm, a reduction in bus travel times can be achieved by proper use of traffic lights. The TSCCS can also track bus group members' current locations and broadcast voice/video amongst a cruising vehicle group, enhancing driver and rider experience. The performance of the developed TSCCS was evaluated in field trials. Our initial experiment results profile the performance of the TSCCS in a small-scale real-life network, with heuristics for designing a large-scale vehicular application then suggested. The data presented here may provide a basic understanding for future advanced studies in this area.

Recently, the authentication schemes based on password have been used widely in network environment. It provides a convenient way for users to authenticate him/her to servers. Previously, Xu et al. proposed an improved smart card based password authentication scheme with provable security. Unfortunately, Song pointed out their scheme cannot withstand impersonation attacks. Moreover, Song proposed two improved schemes to solve it, but his first scheme still cannot withstand impersonation attack. This paper in addition to analyze the weakness of Song's scheme, improved scheme preserving identity privacy also proposes.

A significant issue in VANETs (Vehicular Ad Hoc Networks) is the design of an effective MAC (Medium Access Control) or broadcast scheme which can facilitate the fast and reliable dissemination of critical safety messages to neighboring vehicles in case of an unexpected event. Broadcasting of data and control packets is expected to be crucial in vehicular environment. Most of the broadcasting packet is designed to be delivered on a given frequency during the control channel (CCH) interval set by the IEEE 1609.4 standard [1] (which provides enhancements to the IEEE 802.11p MAC by supporting multi-channel operation). In this paper, the probability based MAC channel congestion control mechanism is developed to cope with rapid topology changes, i.e., vehicles entering and leaving the network, as well as overloaded situations in terms of increased number of vehicles and/or increased amount of data traffic injected without collapsing. Method is also based on the estimation of potential neighboring vehicles through broadcasting Hello messages, and then based on probability model to calculate the expected offset slots for reduce the collision situations, and thus improve transmission performance.

E-pet is an animal-type robot companions, he can be physical or electronic. Reinforcement learning (RL) can be applied to the e-pet. However, the interactive instruction is constituted by complex activities. In this study, we proposed a framework that integrated AI planning technology into RL to generate the solution. In the framework, the e-pet interacts with human and includes two components: environment and agent. The agent exploits AI planning to seek goal state and Markov decision process (MDP) to choose the action and updates each Q-value using Q-learning algorithm. And we proposed the three-level subsumption architecture which including instinct level, perception level, and planning level. We build layers corresponding to each level of competence and can simply add a new layer to an existing set to move to the next higher level of overall competence. We implement the e-pet in a 3D model and train the agent. Experimental result shows that the update of Q-table reduces the number of planning states in the framework.

Vehicular safety application is a critical ITS service in traffic management. In cooperative vehicular safety application, each vehicle must periodically broadcast its current speed, position, heading and identity to the surrounding vehicles. Because of lacking the channel utilization mechanism, inaccuracy of positioning and inconsistency of geographic information, cooperative vehicular safety application suffers many difficulties and limitations. In this paper, we identify out these problems and propose one RSU assisted on-demand vehicular information collection method, which is based on the geographic cell-weighted policy. Finally we show our demonstration and make conclusion.

This paper describes a context aware system that shall be able to effectively classify and store context information, and to reason out user behavior according to context information, in order to provide appropriate service. This study uses ontology to build a context model, as ontology has the ability to express abundant information. In addition, case-based reasoning is used for context reasoning, and refers to the user's historical information, the reasoning ability of the system increases and approaches the user as the number of cases increases. When the behavior of the user is known, this study uses personal ontology to express the user's habit and preferences for services, and uses personal ontology to select appropriate services, and finally, the OSGi platform provides services to meet user requirements. The field of this study is the development of an intelligent space system for common families by providing home services, such as lighting, music, air conditioning, IP-Cam, alarms, etc., the system can integrate service information and provide appropriate services for the user at the appropriate time. Fuzzy ontology is based on the concept that each index term or object is related to every other term in the ontology, via sensors of degrees, for all home devices of membership assigned to that relationship and based on fuzzy signature, as introduced by L.T. Koczy (1999).

The Tandem PiN Schottky (TPS) rectifier features lowly-doped p-layers in both active and termination regions, and is applied in 600-V rating for the first time. In the active region, the Schottky contact is in series connection with a transparent p-layer, leading to a superior forward performance than the conventional diodes. In addition, due to the benefit of moderate hole injection from the p-layer, the TPS offers a better trade-off between the on-state voltage and the switching speed. The active p-layer also helps to stabilise the Schottky contact, and hence the electrical data distributions are more concentrated. Regarding the floating p-layer in the termination region, its purpose is to reduce the peak electric fields, and the TPS demonstrates a high breakdown voltage with a compact termination width, less than 70% of the state-of-the-art devices on the market. Experimental results have shown that the 600-V TPS rectifier has an ultra-low on-state voltage of 0.98 V at 250 A/cm2, a fast turn-off time of 75 ns by the standard RG1 test (I F =0.5A, I R =1A, and I RR =0.25A) and a breakdown voltage over 720 V. It is noteworthy that the p-layers in the active and termination regions can be formed at no extra cost for the use of self-alignment process.

Connection Manager Intelligence Agent's (CMIA) an attractive feature is use the network traffic and behavior with multi-attributes to find the best network devices and connection devices meet user habits that it possible to access various network contents everywhere at any time. In this agent, information process is thoroughly integrated into embedded system for connection manager of MeeGo or Android. This paper proposes a new and generic algorithm for connection manager in the heterogeneous wired or wireless environments. The proposed algorithm uses a Fuzzy Analytic Hierarchy Process theory (FAHP) of Multi-Criteria Decision Making (MCDM) system to achieve scalable, adaptable, and flexible solution. This study implemented an interactive interface through of this function acquisition user behavior and to scholars of the machine used a boosting iterations for User-Case, the algorithm maintains a set of weights as a distribution classes table of case as in the parameter learning by user-case and its quite possible that the Expectation-Maximization (EM) of Maximum Probability Model (MPM) by classification from user behavior. User interaction showed that the agent satisfactorily matched user intent.

This article proposes a Widget-based UPnP framework (WUF) architecture for service discovery between multiple home social networks across the Web. Using a widget base for object-oriented API can be implemented as a user friendly interface for relevant processes, as its program design has high-level components applied in applications and the User-Controls of the API layer in the Visual Studio environment. Thus, this paper focuses on the management scheme for UPnP devices, which uses the standard UPnP device network protocol and the subject of this Agreement Device. This system adopts a multiple system management center (SMC) server into a gateway, which deploys a proxy map to remote devices on a local network using the gateway's IP address, collects all services within the local home network, and exchanges a list of local services with other gateways of remote home networks. Whenever a local device queries specific services, the gateway will response on behalf of the remote devices that have the requested services will be initialization update message in device manager.

The COPE network coding system proposed and implemented by Sachin Katti et al. exploits a physical-layer broadcast characteristic and network coding technique. Though previous studies focus on estimating COPE performance or proposed methods to improve it, there is currently no effective approach to increase network coding throughput. Network coding techniques can be applied to high-traffic network environments, but a large number of transmissions leads to a high collision rate. This paper proposes three mechanisms to exploit the characteristic of network coding. Applying intra-node contention, inter-node contention, and coding-based contention forwarding protocol provides a packet with more coding opportunities from the source to the destination. This system also considers the issue of multiple access categories in large wireless environments, such as a Cyber-Physical System. Simulation result shows that two-stage contentions and coding-based contention forwarding can significantly increase throughput in a network coding network.

IEEE 802.11p/WAVE (Wireless Access in Vehicular Environments) is an emerging family of standards intended to support wireless access in Vehicular Ad Hoc Networks (VANETs). Broadcasting of data and control packets is expected to be crucial in this environment. Both safety-related and non-safety applications rely on broadcasting for the exchange of data or status and advertisement messages. Most of the broadcasting packet is designed to be delivered on a given frequency during the control channel (CCH) interval set by the IEEE 1609.4 draft standard. However, the AOS (Adaptive Offset Slot) mechanism is firstly developed based on the estimation of potential neighboring vehicles through broadcasting Hello messages, and then calculating the expected offset slots for reduce the collision situations, and thus improve transmission performance.

In this paper, we study overload handling for frequent-pattern mining in online data streams. For a mining system with an e-deficient synopsis based algorithm, we propose a load shedding scheme to deal with the overload situation. The heavy workload of the mining algorithm lies mostly in the great deal of itemsets which need to be enumerated and counted by the mining algorithm. Therefore, our proposed scheme of load shedding involves the maintenance of a smaller set of itemsets, so the workload can be lessened accordingly. The unrecorded itemsets can be fast approximated for their counts when necessary. According to experimental results, the load shedding scheme can increase the throughput of the mining system and thus help manage the overload problem effectively to a certain extent.

A context model is defined with information represented and gathered from sensors, user profile, environment and other sources. The main advantage of using ontology is the ability to express machine-interpretable definition on basic concept and interrelation that enables the reuse of the constructed context models. The method of analyzing and designing context ontology will influence the relationship between context information and expression of user activities. By analyzing events, the associated services are defined. Once an event occurs to a particular user with a context model, we provide appropriate services to the user by using the most similar event in context ontology to execute the rule-based system.

This Connection Manager Intelligence Agent (CMIA) is an attractive feature of use the network traffic and behavior with multi-attributes to find the best network devices and connection devices meet user habits that it possible to access various multimedia contents everywhere at any time. In this agent, information process is thoroughly integrated into embedded system for connection manager of Meego or Android. We have implemented an interactive interface through this function (User interactive interface are based on Qt Creator IDE and CMIA) acquisition user behavior and to scholars of the machine. We have a successful user interaction of the agent can be decision making the choice of match the user intent.

The enhanced photoelectric conversion is demonstrated in nanostructured glass substrates for a-Si thin film solar cell. The nanostructured glass substrates were fabricated using nanosphere lithography and RIE technique. The nanostructure substrates provide antireflective and light scattering characteristics, which enhance the broadband light absorption, especially in near-infrared range. Finally we demonstrate the patterned glass substrates (nipple shape arrays) which are useful in light absorption of a-Si thin film solar cell. Compared to a flat glass substrate cell and Asahi-U glass substrate cell, the power conversion efficiency enhancement achieved 48.4% and 3.1%, the Jsc enhancement achieved 51.6% and 8%.

A 300-V TMBS® (Trench MOS Barrier Schottky) rectifier with novel active-cell and termination design is first proposed and demonstrated. The device features a combination of p-transparent anode and Schottky contact, considerably reducing on-state voltage and ensuring a high degree of performance uniformity. A floating p-layer is used in termination region under a trench area to significantly enhance the blocking capability to 95% of the ideal breakdown voltage. In addition, the new termination design is area-efficient, being only 30 to 40 μm in width, which is less than 33% of the conventional guard-ring terminations. Experimental results have shown that the new 300-V TMBS structure with the novel active cell and termination design exhibits ultra-low on-state voltage of less than 0.9 V at 250 A/cm2, a fast turn-off time lower than 55 ns and a high breakdown voltage over 380 V. It is noteworthy that these new components in active and termination regions can be formed without any additional masks, and hence at no extra cost.

For the first time, we report a low temperature silicon thin film deposition technology using high density plasma for high performance and low cost solar cells with embedded transistor modules. For process temperature at 140°C, energy conversion efficiency of 9.6% and electron mobility of 1.1 cm2/V-s have been achieved. Device performance with process temperature down to 90°C and 60°C has also been examined in depth. This very low process temperature technology can integrate energy harvesting with electronics on inexpensive and flexible substrates.

One of attractive features of electronic-pets (e-pets) is interaction between the user and the e-pet. The interaction, however, is usually limited to using the predefined commands. In this paper, we present a way of involving the user in helping an e-pet learn high-level behaviors based on basic actions. The high-level behaviors are derived with planning, and the execution of the behaviors is then trained with reinforcement learning. In this research, we explain how we use a partially observable Markov decision process and the hierarchical task network planning for designing behaviors. A Q-learning method is then applied to the training of the e-pet for achieving the correct behavior. A prototype is presented to show its feasibility and effectiveness.

In this paper, we propose a tree-based adaptive broadcasting (TAB) algorithm for data dissemination to improve data access efficiency in vehicle communications. The proposed TAB algorithm first constructs a broadcast tree to determine the broadcast frequency of each data, and splits the broadcast tree into some broadcast wood to generate the broadcast program. In addition, this paper develops an analytical model to derive the mean access latency of the generated broadcast program. In light of the derived result, the bandwidth for both index channel and data channel can be optimally allocated to maximize bandwidth utilization. Furthermore, to evaluate the effectiveness of the proposed strategy, experiments are demonstrated as well. This study argues for the use of an interest profile (ontology) of drivers and information about vehicles to form a group of interest for Vehicle ad hoc Networks (VANETs). The performance of the approach is evaluated by performing computer simulations. From the experimental results, it can be seen that the proposed mechanism is feasible in practice.

In many applications, data-stream sources are prone to dramatic spikes in volume, which necessitates load shedding for data-stream processing systems. In this research, we study the load-shedding problem for frequent-pattern discovery in transactional data streams. A load-controllable mining system with an e-deficient mining algorithm and three dedicated load-shedding schemes is proposed. When the system is overloaded, a load-shedding scheme is executed to prune a fraction of unprocessed data. From the experimental result, we find that the strategies of load shedding can indeed lighten the system workload while preserving the mining accuracy at an acceptable level.

La dopant positioning at HfO 2 ultra-thin films was successfully achieved by the co-sputtering method. The depth profiles of graded doping HfLaO (7 nm)/p-Si structures after 850°C RTA were studied. From the nano-AES results, the out-diffusion of Hf atom into Si substrate increases when the La dopant is co-deposited in the upper bond and forming HfLaO/HfO 2 /Si structures. On the other hand, the out-diffusion of Hf atoms into Si substrate is suppressed when the La is doped in the lower bond and forming HfO 2 /HfLaO/Si structures. It is found that the chance to form silicate becomes insignificant due to less oxygen out-diffusion into Si in the later case. Above is consistent with the binding energies of our XPS results. The electrical properties of different doping locations were measured and compared. The thickness of silicate layer is suggested to be the origin of leakage current.

Ultra-thin yttrium oxide (Y 2 O 3 ) films (physical thickness of 7 nm) were deposited on p-Si substrates by RF sputtering for MOS applications. The structural properties of the Y 2 O 3 gate dielectrics were studied after RTA from 650 to 850°C. The crystalline phase and chemical bonding state of the films were characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), respectively. According to the XRD patterns, Y 2 O 3 films remain amorphous after 850 °C annealing. Moreover, also confirmed by XPS results, the formation of yttrium silicates (YSiO) was observed after 650°C annealing, and the silicate thickness increases with the annealing temperature. It is suggested that the thickness of the silicate layer YSiO dominates the gate leakage current of the MOS capacitors.

Continuous efforts have been made to improve the IGBT performance, especially in terms of the trade-off between the on-state voltages and turn-off energy losses. Recently the carrier density enhancement (CDE) technologies, which aim at increasing the carrier densities near the emitter/cathode side of the IGBTs, are of great interest to the industry. In this paper, an insight introduction of the state-of-the-art CDE technologies is provided. In addition, a novel dual-gate trench IGBT which utilises an embedded low-gain PNP and thyristor to achieve an ultra-low on-state voltage without deteriorating the switching speed is presented.

In this paper, a new Trench Insulated Gate Bipolar Transistor (TIGBT) which features a double-gate (DG) structure is presented. The new DG-TIGBT can enhance the excess carrier density near the emitter side of the IGBTs so that the conductivity modulation in the N- drift region is stronger than that presents in the conventional IGBTs. In addition, these excess holes can be extracted to the emitter via MOS channels during the turn-off transient, so the switching speed and losses of the DG-TIGBT are virtually unaffected by the extra carrier charge. In this work, we have demonstrated a 600-V DG-TIGBT which has an ultra-low on-state voltage and maintains the same turn-off speed as the conventional TIGBT.

In this paper, we demonstrate TaN/fluorinated HfO2 CMOS devices, focusing on symmetry and asymmetry fluorine incorporation at top or bottom HfO2 interfaces. 16% permittivity enhancement, 65% and 91% mobility increases for electron and hole, respectively, under high electric field was achieved. Reliability of n- and p-MOSFET was improved 3 orders and 8% for GIDL and hot carrier immunity, respectively. A physical model of shallow and deep trapping level affected by fluorine was proposed to explain the NBTI and PBTI improvements.

We present a novel hardware architecture supporting diamond search and fast full search for block matching motion estimation. It can handle irregular data flow of these fast algorithms without pipeline bubbles, and reduce computation of duplicated search positions. The proposed architecture needs preprocessing with a small amount of computational power while performing fast full search and is suitable for the platform-based video coding system. While the diamond search mode can be applied for real-time requirements, we can choose the fast full search mode, which adapts the processing cycles to picture contents and preserves the same quality of full search block matching (FSBM), for applications of high picture quality or compression ratio. It needs only 9K gates and one additional memory of search range size and is more cost-effective than the conventional systolic array architecture.

We propose the idea of using a grating structure for solving the problem of the incomplete quasi-phase matching (QPM) period and demonstrate the simulation results of phase compensation in achieving efficient round-trip optical parametric oscillation in periodically poled LiNbO/sub 3/ (PPLN). The layout of a monolithic optical parametric oscillator (OPO) with two surface gratings at both ends is shown. The two gratings are chirped to guarantee that their phase variations over the Bragg reflection windows are larger than 2/spl pi/. One of them has a length of 1 mm and the other has a length of 0.8 mm. The pump input is applied from the long grating side and the signal output is obtained from the short grating side. The whole PPLN length is 5 mm. For our numerical study, we consider the pump wavelength at 1064 nm and signal wavelength at 1550 nm. The idler wavelength is hence at 3.393 /spl mu/m. The corresponding QPM period of PPLN is 29.6 /spl mu/m. The central grating period is 361.83 nm, which corresponds to the Bragg wavelength 1550 nm. To obtain numerical results, we solved the coupled equations for the forward and backward pump complex amplitudes, the forward and backward signal complex amplitudes, and the forward and backward idler complex amplitudes.

Broadband quasi-phase matched optical parametric generation with periodically poled LiNbO/sub 3/, based on a non-collinear configuration, is reported The broadest signal spectrum covers from 1.734 to 1.962 /spl mu/m when pumped with a Nd:YAG laser.