An efficient networking protocol for internet of things to handle multimedia big data

In recent years, the emergence of multimedia big data (MBD) due to the excessive use of mobile Internet of Things (ioT) is imposing various challenges to develop efficient communication with the digital world. In this aspect, Mobile Adhoc Network based IoT (MANET-IoT) system is becoming popular due to its greater mobility support and cost-effective nature. A mobile ad hoc network (MANET) consists of randomly placed, battery-powered, moving nodes without an infrastructure that can administer and control traffic in the IoT network. In the MANET-IoT network, the major problems include energy consumption and congestion control to handle MBD data. In this paper, we present two proposals for solving these problems. In the first proposal, a new clustering approach that depends on a well-known protocol called the Low Energy Adaptive Clustering Hierarchy (LEACH) been used in a wireless sensor network (WSN) with modification to adapt to the MANET-IoT’s mobility. Our proposal for applying LEACH to a MANET-IoT consists of rounds, each containing three ordered phases as follows: (1) the announcement phase, in which all nodes announce their remaining energy and the node with the original message also announces itself; (2) the setup phase, in which all cluster heads are selected based on the probability factor with a cycling method; and (3) the steady state phase, in which message delivery to all nodes occurs using several types of links. The second proposal is to provide congestion control for all mobile nodes by link utilization that can support different data rates depending on the link status. Simulation results comparing our modified LEACH protocol to state-of-the-art protocols with utilized links show a great enhancement in energy consumption, received data, throughput, and delay.

     

IPBGA: a hybrid P2P based grid architecture by using information pool protocol

The current representatives of Grid systems are Globus and Web services, however, they have poor scalability and single point failure. It is these two factors which make the building of an improved P2P and grid hybrid framework for resource management and task schedule such a popular research topic. This paper differs from current research because it puts forward an Information Pool Based Grid Architecture (IPBGA), which is a real sense hybrid of P2P and grid instead of only introducing P2P methods into grid systems for resource management. Based on virtualizations, abstract physical resources and tasks to be, the information requests from resources for tasks and appeals from tasks for resources are upgraded as information services by using an information pool protocol (IPP). Thus, grid resource management and task scheduling are regarded as information matching by IPP which is adaptive to the heterogeneous, dynamic, and distributed characteristics of a grid system. Tri-Information Center (Tri-IC) and source ranking mechanisms are presented in IPP to improve robustness, prevent sybil attack, and to discourage free riding. Experiments and theory analysis show that the IPP of the IPBGA is more efficient and robust in dealing with information while both the bandwidth and process costs are less.

Employing early model-based safety evaluation to iteratively derive E/E architecture design

ISO 26262 addresses development of safe in-vehicle functions by specifying methods potentially used in the design and development lifecycle. It does not indicate what is sufficient and leaves room for interpretation. Yet the architects of electric/electronic systems need design boundaries to make decisions during architecture evolutionary design without adding a risk of late changes. Correct selection of safety mechanisms from alternatives at early design stages is vital for time-to-market of critical systems. In this paper we present and discuss an iterative architecture design and refinement process that is centered around ISO 26262 requirements and model-based analysis of safety-related metrics. This process simplifies identification of the most sensitive parts of the architecture, selection of the best suitable safety mechanisms to reduce thereby failure rate on the system level and improve the metrics defined by the standard. To support the defined process we present the metamodels that can be integrated with existing DSL (domain-specific language) frameworks to extend them with information supporting further extraction of fault propagation behavior. We provide a framework for architecture model analysis and selection of safety mechanisms. We provide details on the model-based toolset that has been developed to support the proposed analysis and synthesis methods, and demonstrate its application to analysis of a steer-by-wire system model and selection of safety mechanisms for it.     

An area- and energy-efficient hybrid architecture for floating-point FFT computations

Floating-point fast Fourier transform (FFT) has been widely expected in scientific computing and high-resolution imaging applications due to the wide dynamic range and high processing precision. However, it suffers high area and energy overhead problems in comparison to fixed-point implementations. To address these issues, this paper presents an area- and energy-efficient hybrid architecture for floating-point FFT computations. It minimizes the required arithmetic units and reduces the memory usage significantly by combining three different parts. The serial radix-4 butterfly (SR4BF) is used in the single-path delay commutator (SDC) part to minimize the required arithmetic units with 100% adder utilization ratio obtained. A modified single-path delay feedback (MSDF) architecture is proposed to achieve a tradeoff between arithmetic resources and memory usage by using the new half radix-4 butterfly (HR4BF) with 50% adder utilization ratio obtained. The intermediate caching buffer is modified accordingly in the MSDF part. By combining both the advantages on arithmetic units reducing and memory usage optimization in different parts, the optimized area and power are obtained without throughput loss. The logic synthesis results in a 65 nm CMOS technology show that the energy per FFT is about 331.5 nJ for 1024-point FFT computations at 400 MHz. The total hardware overhead is equivalent to 460k NAND2 gates.     

基于协议无感知转发技术的信息中心网络：设计、实现与应用

软件定义网络(SDN)的核心思想是将网络中控制平面和数据平面进行解耦,采用集中控制的方式给用户提供开放可编程的接口。信息中心网络(ICN)则集中在对内容进行命名和基于内容名字的路由。协议无感知转发(POF)是一种支持自定义协议的SDN转发技术。随着未来网络技术的研究与发展,基于SDN思想来实现ICN则可能成为一种解决方案,因而提出了一种基于POF技术的ICN网络设计方案与实现,并搭建了基于POF技术的ICN实验床。多人视频会议应用表明,该设计方案的正确性与可行性,不仅能转发ICN数据包,还能很好地实现实时性应用。     

车载物联网技术及其应用探讨

随着车载物联网技术的高速发展,车载物联网技术已经开始被多个领域所应用,并取得了很大的成功,如何实现车载物联网技术的更高发展成为当前热门研究课题.本文首先详细概述了车载物联网相关理论,然后分析了当前车载物联网技术在不同领域中的应用,最后对当前我国车载物联网技术所面临的挑战进行了详细的分析研究.     

基于Region多层结构P2P计算网络应用层多播协议分析

在基于Region多层结构P2P计算网络模型下,对表征该模型下实施应用层多播协议的数据通道传输质量指标压力和伸展率进行了较为详尽研究,分析了Region规模k和网络规模N对数据通道传输质量指标的影响,并量化了指标,给出了计算公式,并提出了在实际应用中应综合考虑伸展率和压力的思想。通过理论和模拟仿真分析得：伸展率与网络或Region的规模几乎无关,压力与网络或Region的规模成正比;降低伸展率会导致压力增加,反之亦然;数据通道上的伸展率为O(logN),节点的压力为O(1)。     

SUPNET: An end-to-end solution to scalable unstructured P2P networking

Despite many improvements on original unstructured P2P networks, these systems still suffer from several problems, the most important of which are, (a) lack of guarantees on the integrity of the network topology in the face of churns, (b) excessive traffic cost and (c) poor quality of search results. This paper introduces an end-to-end scalable unstructured P2P networking solution called SUPNET to address many of these issues. SUPNET is based on our pragmatic, design oriented approach to engineering complex networks. Rather than modeling dynamical behavior in already-existing networks, we actively design and implement local stochastic dynamics so that an engineered global system, with predictable structures emerges. The resulting protocol, SUPNET, consists of two sub-protocols for network management and content search. The network management sub-protocol is scalable and highly robust and is capable of utilizing the heterogeneous distribution of network resources. Its high stability is the result of implementation of a novel distributed feedback mechanism. The search sub-protocol is capable of locating every item, even if a single copy of that item exists in the network, while producing a traffic that scales provably sub-linear with the network size. It also contains mechanisms for very efficient location of popular items as well as distributed parameter tuning algorithms. These, along with inherently self-organized and de-centralized operation, relative ease of implementation and solid analytical foundation, make SUPNET a compelling solution for unstructured P2P networking.

三层Client／Server构架结合Datasnap技术的应用研究

文章对三层C／S构架的具体结构进行了分析和比较，提出了基于Datasnap技术的三层系统的实现方案。结合质监电子政务系统，对三层构架中的通用数据访问接口和安全控制实现进行了分析研究。     

An application of digital point cloud to historic architecture in digital archives

Currently, the process of conservation by digitizing historic buildings is a key technology in cultural heritage preservation that needs further improvement. However, a comprehensive survey of projects of digital archives shows that traditional, time-consuming construction methods were adopted most, as in taking pictures or cartographing physical buildings through AutoCAD to construct digital data. This study adopted reverse engineering to explore digitalizing constructions and employed a fast and precise 3-D laser scanner to retrieve point cloud data and then import the data into Rapidform XOR2, an application used in reverse engineering, to process point cloud data and construct 3-D models. The results were then converted from 3-D models into 2-D pictures by parameterization software Pro/ENGINEER to provide designers precise and realistic dimensional data, which effectively reduced time in cartography and increased historic building dimension precision during digitalization. The foregoing data was documented and compared, and a digital value-added effect could be possible in the future.     

利用Rabbit3000芯片设计以太网接入功能与TCP/IP协议栈的优势分析

首先分析了网络方案设计过程中需要注意的三个问题,介绍并分析了现有的几种设计方案,并以Rabbit3000芯片为例,分析了该芯片在构建以太网接口和TCP/IP协议栈方面的优势。     

Passive testing and application to the GSM-MAP protocol

Passive testing is the process of collecting traces of messages exchanged between an operating implementation and its environment, in order to verify that these traces actually belong to the language accepted by the provided finite state machine specification. In this paper, we present an extension of the existing algorithms to consider an extended finite state machine as the specification. An algorithm is also introduced to take into account the number of transitions covered. These techniques are illustrated by the application to a real protocol, the GSM (global system for mobile communication)-MAP (mobile application part).     

An efficient and security dynamic identity based authentication protocol for multi-server architecture using smart cards

Generally, if a user wants to use numerous different network services, he/she must register himself/herself to every service providing server. It is extremely hard for users to remember these different identities and passwords. In order to resolve this problem, various multi-server authentication protocols have been proposed. Recently, Sood et al. analyzed Hsiang and Shih's multi-server authentication protocol and proposed an improved dynamic identity based authentication protocol for multi-server architecture. They claimed that their protocol provides user's anonymity, mutual authentication, the session key agreement and can resist several kinds of attacks. However, through careful analysis, we find that Sood et al.'s protocol is still vulnerable to leak-of-verifier attack, stolen smart card attack and impersonation attack. Besides, since there is no way for the control server CS to know the real identity of the user, the authentication and session key agreement phase of Sood et al.'s protocol is incorrect. We propose an efficient and security dynamic identity based authentication protocol for multi-server architecture that removes the aforementioned weaknesses. The proposed protocol is extremely suitable for use in distributed multi-server architecture since it provides user's anonymity, mutual authentication, efficient, and security.     

基于C/S与B/S混合架构的排水地理信息系统

根据排水行业管理和服务工作的自身特点,设计和开发了一套基于C/S与B/S混合架构模型的城市主城区排水地理信息系统。着重对系统体系架构、接口设计、系统的多项关键技术进行了详细的分析和论述,并对系统实现等做了阐述。利用公共数据库技术和该文提出的DLODI模型有效地解决了多源数据的集成与共享问题。     

An efficient and effective similarity measure to enable data mining of petroglyphs

Rock art is an archaeological term for human-made markings on stone, including carved markings, known as petroglyphs, and painted markings, known as pictographs. It is believed that there are millions of petroglyphs in North America alone, and the study of this valued cultural resource has implications even beyond anthropology and history. Surprisingly, although image processing, information retrieval and data mining have had a large impact on many human endeavors, they have had essentially zero impact on the study of rock art. In this work we identify the reasons for this, and introduce a novel distance measure and algorithms which allow efficient and effective data mining of large collections of rock art.     

An object class-uncertainty induced adaptive force and its application to a new hybrid snake

Object segmentation is of paramount interest in many imaging applications, especially, those involving numeric, symbolic, syntactic, or even high level cognitive knowledge perception. Among others, “snake”—an “active contour” model—is a popular boundary-based segmentation approach where a smooth curve is continuously deformed to lock onto an object boundary. The dynamics of a snake is governed by different internal and external forces. A major limitation of the present framework has been the difficulty of incorporating object-intensity driven features into snake dynamics so as to prevent uncontrolled expansion/contraction once the snake leaks through a weak boundary region. In this paper, a local-intensity-driven “adaptive force” is introduced into the model using object class-uncertainty theory. Given a priori knowledge of object/background intensity distributions, class-uncertainty theory yields object/background classification of every location and establishes its confidence level. It has been demonstrated earlier that confidence level is high inside homogeneous regions and low near boundaries. In the current paper, object class-uncertainty theory has been applied to control snake deformation leading to a new adaptive force acting outward (expanding) inside intensity-defined object regions and inward (squeezing) inside background regions. It has been demonstrated that the method possesses potential to resist uncontrolled expansion of a snake contour (for an expanding type) inside background after leaking through a weak boundary. Further, it has been shown that the adaptive force operates in a complementary fashion with the image intensity gradient by reducing its strength near boundaries using the confidence level of classification. Another major contribution of this paper is the formulation of a “hybrid snake” (HS)—a new model, where an initial contour is gradually deformed over a hybrid energy surface composed of some direct energies (e.g., internal energies) and other indirect energies contributed by local contour displacements over a force-field (e.g., image or user-constrained force-field). Applications of the proposed adaptive force-enabled HS on different phantom and real images have been presented and comparisons have been made with a conventional snake (CS). Finally, a quantitative comparison based on computer-generated phantoms at various levels of blur and noise has been provided.     

A hybrid PC/PLC architecture for manufacturing-system control—theory and implementation

This paper presents a novel and generic PC/PLC-based software/hardware architecture for the control of flexible manufacturing workcells. The proposed implementation methodology is based on the utilization of any one of the available formal discrete-event-system control theories in conjunction with state-of-the-art industrial programmable-logic controllers (PLCs). The methodology has been illustrated to be a viable technique through its actual implementation in our laboratory using a robotic-workcell testbed. The specific control theory used is a combination of Extended Moore Automata and Ramadge-Wonham Automata that has been developed by our research group. The modular control software architecture has been developed for MS-Windows environments (running on one PC interfaced to the PLCs) and allows the use of different formal control theories as well as different commercial PLC hardware. The effective graphical user interface provides a transparent programming environment, where users are not expected to have a full knowledge of the formal control theory used.