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Smart home is a system to control home devices which are more and more popular in our daily life. Mobile intelligent terminals based on smart homes have been developed, make remote controlling and monitoring possible with smartphones or tablets. On the other hand, 3D stereo display technology developed rapidly in recent years. Therefore, a iPad-based smart home system adopts autostereoscopic display as the control interface is proposed to improve the userfriendliness of using experiences. In consideration of iPad’s limited hardware capabilities, we introduced a 3D image synthesizing method based on parallel processing with Graphic Processing Unit (GPU) implemented it with OpenGL ES Application Programming Interface (API) library on IOS platforms for real-time autostereoscopic displaying. Compared to the traditional smart home system, the proposed system applied autostereoscopic display into smart home system’s control interface enhanced the reality, user-friendliness and visual comfort of interface.

As an advanced technology, satellite remote sensing has been applied in a variety of fields and has brought numerous social benefits. This paper introduces a new operational satellite imagery processing system and conducts a case study using it by processing ZY-02C and ZY-3 satellite imagery. By way of this case study, this paper proposes a workflow involving the key generation technologies with fully automatic generation of advanced remote sensing products, such as the digital elevation model (DEM), the digital orthophoto map (DOM), and the high-resolution color-fused image. The proposed workflow in this system tackles the key practical issues related to the domestic satellite imagery process, such as low processing efficiency, low utilization, poor integration, etc. This system utilizes the following key generation technologies: automatic registration between the satellite imagery and the existing multi-geographic data, strip aerial triangulation of three-line array satellite images, multi-sensor image registration and fusion, dense matching of photogrammetric point clouds, and automatic correct splicing of wide range images. The proposed process system consists of two parts. The first part is the creation of a geographic information production mode with no manual intervention. This mode aims to improve the accuracy and efficiency of mass domestic satellite images to produce highly precise orientation by using global public basic geographic information databases like Map World, Google Earth, etc. The second part is the design of a workflow to ensure the stability of the production time and quality of domestic satellite imagery's advance product generation. Finally, this paper also discusses the accuracy of the process of image orientation and the precision of advanced products such as high-resolution color-fused image (ZY-02C), DEM (ZY-3), and DOM (ZY-3). The results show that the products of the proposed process system meet the requirements in both efficiency and quality, and the proposed process system is ready for future real-time domestic remote satellite imagery generation.

This paper provides a error modeling and calibration method to the geolocation error problem arising in the generation of digital elevation model (DEM) via interferometr ic synthetic aperture radar (InSAR) technique. DEM error is divided into two parts, systematic error and random error, they are modeled respectively. The baseline error is of crucial importance in the systematic error, it causes a slowly changed height error in the azimuth and a small tilt in the ground range of the DEM, a 2-D polynomial function is used to fit the systematic height error. The corrected DEM is obtained by removing the systematic error from the raw DEM. Computer simulation results prove the availability of the method. Keywords: InSAR; DEM; height error modeling; baseline error; error calibration; GCPs; least-squares method 1. INTRODUCTION The InSAR technique is a very efficient tool for terrain he ight measurement by the interferometry of two or multiple SAR images which are acquired from two or multiple antennas with a slight look angle difference [1]. It can get the DEM of the Earth's surface quickly in all kinds of weather and day or night. DEM is of fundamental importance for a broad range of commercial and scientific applications. For example, many geoscience areas, like hydrology, glaciology, forestry, geology, oceanography, and land environment, require precise and up-to-date information about the Earth's surface and its topography. Nevertheless, in the process of DEM generation, the errors of the instrument, orbit, and processing parameters which have been used in the InSAR processing affect the accuracy of DEM significantly. TanDEM-X mission provides an example [2], The TanDEM-X mission is the first bistatic satellite synthetic aperture radar mission which is formed by flying TanDEM-X and TerraSAR-X in a closely controlled helix formation. The primary mission goal is the derivation of a high-precision global digital DEM according to High-Resolution Terrain Information (HRTI) level 3 accuracy. The finite precision of the baseline knowledge and uncompensated radar instrument drifts along with some other parameter errors introduce errors that may compromise the height accuracy requirements. To fulfill the its demanding requirements, a DEM calibration method which uses absolute height references and the information provided by adjacent interferogram overlaps is pr oposed to minimize th e residual height errors. It can be seen that the correction of systematic height errors in the DEM is necessary to achieve the specified accuracies [3-4]. In the future InSAR system, the required DEM accuracy will be more and more precise, therefore, the DEM calibration will play a more important role in the DEM post-processing. The main purpose of this paper is to describe the influe nces of the systematic error and obtain a more precise DEM by removing it from the overall DEM. Section 2 provides a brie f analysis of the total DEM height error, and classifies it into two groups, the systematic error and the random error. Section 3 sets up the models of systematic error especially the baseline error and presents a DEM calibration method. Sec tion 4 is the computer simulation results which prove the availability of the method. The paper concludes in Section 5.

An energy efficiency scheme based on the coordination of management and control is proposed to reduce the power consumption in multi-domain WSON. Experiments are conducted on the energy efficient multi-domain WSON testbed (EEMWT) to assess the performance of the scheme.

With ever increasing requirements posed by significant advances in networking, service providers may use traffic engineering (TE) techniques to efficiently manage resources and provide consistent quality of service (QoS). Briefly, constraint-based path computation involves the pruning of links that do not satisfy constraints and subsequently using the shortest path algorithm on the resulting sub-graph. This process is simple and efficient when the path involves only one domain, but can potentially become severely resource heavy, complex, and inefficient when multiple domains are involved. To address this problem, the Path Computation Element (PCE) architecture has been proposed to allow multi-layer path computation to be simple and efficient. The PCE architecture introduces a special computational entity that will cooperate with similar entities to compute the best possible path through multiple layers. This paper analyses the PCE architecture and the traditional method to computing the routing through multiple layers, and then an improved scheme of path selection for multi-layer network based on PCE and VNTM is present and evaluated on the simulation platform of NSFNET, which is used to avoid traffic redundancy caused by low layer's invisibility to the high layer.

Clock synchronization is an essential problem faced by packet transport network. PTP (precise time protocol) can be used to solve this problem. Its feasibility has been verified by related literatures. In this paper, we use the OPNET simulation platform to further study the key factors affect the clocks' accuracy of packet-based synchronization schemes, e.g., queuing disciplines, number of nodes that PTP messages have passed, deployment of the PTP enabled router, and network traffic load. We intend to answer the question how much influence can each factor make to the clocks' synchronization performance.

In this paper, a p-cycle generation algorithm is proposed that can protect service of static traffic model in WDM network. As the basic p-cycle sets calculated by algorithm such as the straddle link algorithm (SLA) always contain a straddle link in it. That is why the protection efficiency is higher than bidirectional line switch ring (BLSR). Any idle resource can be used for traffic restoration. But if the resource is not configured carefully then not all the resource of idle state can be utilized efficiently. Some extensions of algorithms are brought into effect to improve the protection capability. Based on these extensions, a novel iterative expanding p-cycle is introduced. A platform is constructed in OPNET modeler to verify the performance of this algorithm. Simulation results show that after several expansions for the basic p-cycle sets, the efficiency is improved. The pre-configured resource is deployed before any requests come. Comparison between different network topologies is studied. Finally, the results are analyzed and some directivity is given for further research.

A reconfigurable protection is extended in ASON survivability testbed SURBED, the performance and extra overhead are presented and also compared with several survivability techniques (1+1, shared mesh, rerouting, etc) in SURBED. Pre configured protection cycles (p-cycle) is a kind of preconfigured protection mechanism that can have mesh-like resource efficiency and ring-link protection speed. But under multi-region survivable network, the topology and resource information is not always available due to policy reasons or other else, so distributed approach with agent negotiation is attractable. As the dimensions of WDM optical network grows larger and larger, it tends to be a mesh structure. Based on SURBED, we take extensive simulation to investigate the performance of different signaling strategies by multi-region agent negotiations. Unlike previous work, we focus on the reconfiguring process rather than the switching over operation of control plane in ASON. The backbone is overlaid, in which most of devices are IP router networks. Routers are interconnected by fibers or SDH or WDM links. It is the same with non-reconfigured p-cycle, the reconfiguration need a criterion, and here we use the network real-time performance as a reconfiguration trigger to take actions on p-cycle reconfiguration.

In large dynamic networks it is extremely difficult to maintain accurate routing information on all network nodes. The existing studies have illustrated the impact of imprecise state information on the performance of dynamic routing and wavelength assignment (RWA) algorithms. An algorithm called Bypass Based Optical Routing (BBOR) proposed by Xavier Masip-Bruin et al can reduce the effects of having inaccurate routing information in networks operating under the wavelength-continuity constraint. Then they extended the BBOR mechanism (for convenience it's called EBBOR mechanism below) to be applied to the networks with sparse and limited wavelength conversion. But it only considers the characteristic of wavelength conversion in the step of computing the bypass-paths so that its performance may decline with increasing the degree of wavelength translation (this concept will be explained in the section of introduction again). We will demonstrate the issue through theoretical analysis and introduce a novel algorithm which modifies both the lightpath selection and the bypass-paths computation in comparison to EBBOR algorithm. Simulations show that the Modified EBBOR (MEBBOR) algorithm improves the blocking performance significantly in optical networks with Conversion Capability.

T-MPLS is a connection-oriented packet switched solution for transport networks. In this paper, we investigate the signaling mechanism in T-MPLS control plane with BRR-N and SRR strategies and simulate it in OPNET modeler. The standardization process is pushed by ITU-T and IETF. T-MPLS is much easier to achieve a convergent packet platform for any L2 protocol. It focuses on the packet transport application that adheres to the standard groups. With the proposed mechanisms, the performance was deeply studied in this paper for the controlling overhead and the block probability of the transport network. The realization of the T-MPLS network router model and its associated structure is also presented to show the detail functional components. The convergent packet transporting platform for any L2 and L3 protocols is attractive for future telecom applications. Keywords: T-MPLS, backward reservation, forward reservation, packet transport

Although Gigabit T-MPLS technology has not been widely used for transmission network, it is attracting more and more attention. The design of high-speed data switching is the key technology in T-MPLS. In this paper, one method that implements 4 ports Gigabit T-MPLS switch chip on FPGA which is used for TDM over T-MPLS exchanging is introduced, and the simulation and verification results will be given in the conclusions. It researches the requirements of transport plane in T-MPLS and analyses the architecture, and demonstrates a design of TDM in Transport MPLS based on FPGA through a testbed which is used to explore and implement the concepts of Transport MPLS.

It researches the requirements of control plane in T-MPLS and analyses the architecture of control plane based on TMPLS testbed. With the growth of the demand for packet transport services, packet transport network is becoming the core technology for transport network, especially T-MPLS. Because of simply implement, independent control plane, complete OAM, T-MPLS becomes the most promising technology for packet transport network. The control plane is responsible for handling dynamically and in real-time network's esources in order to manage the establishment and deletion of label switch path(LSP), and for disseminating and discovering network topology and resource availability through the exchange of control (signaling and routing) messages between neighbor nodes over the data communication network (DCN). It is composed of mainly four modules, connection controller (containing signaling module), routing, resource manager, and protocol controller module. The four modules interact with each other to complete the control plane's functions. The flow of every module is designed in this paper to complete control plane's software programming.

T-MPLS is a connection-oriented packet switched solution for transport networks. The standardization process is pushed by ITU-T and IETF, many recommendation appeared in these days. T-MPLS is much easier to achieve a convergent packet platform for any L2 protocol. It focuses on the packet transport application that adhere to the standard groups. Although IETF PWE3 WG have already specified the common architecture for L2/L3 service encapsulation, as different service always has different characteristics. So we propose a control mechanism for dual label transport across T-MPLS in this paper, through which we can easily achieve a convergent packet transporting platform for any L2 and L3 protocols, . At last, a flow chart for T-MPLS realization and a FSM structure have been introduced.

Discusses the network architecture designed for providing carrier class metro Ethernet services over T-MPLS packet transport network. Analyzes its characteristics and advantages from the aspects of data transport, OAM, end-to-end QoS, protection mechanism and interworking.

It Researches key technologies and hardware node structure of the Transport MPLS packet network. Main technology is super high speed FPGA. The transport plane adapts the layer 3 service signals from client equipments and forwards them. There are two types of node in transport plane, edge node (EN) or core node (CN), and the nodes realized with large-scale FPGA chip have three main function units and six types of board. The EN adapts the layer 3 service signals such as TDM, Packet and Cell to TM signals by add shim. The CN is responsible for the TM signals switching in higher speed than traditional packet network such as Ethernet. Control plane is embedded in a FPGA chip and designed based on the ASON core technique (GMPLS) such as the transport label switching path (T-LSP) maintaining (set up, release, state monitoring), route controlling and protect recovering and so on.

This paper introduces a novel method to design SNMP-based network management system of GE-PON and its management applications. Then it introduces how to establish a web server on GE-PON NMS platform, and methods to realize the system in the Manager and Agent. Finally, a simulation result is given to show the feasibility and superiority of this method.

T-MPLS is regarded as one of the most important transport technologies in the next generation network, it a connection oriented packet transport technology develop from MPLS techniques, now defined by ITU-T SG13 & SG15. In this paper, we analyze the architecture of the transport MPLS networks, the most important building blocks for the modular design of the common T-MPLS equipment are introduced. And based on the functional blocks, a four-layer simulation T-MPLS node structure is developed. And the simulation environment is introduced. Many kinds of research can be done using this T-MPLS simulation tool, such as the research of the feasibility T-MPLS design, the inter-working between the T-MPLS and the PWE.

A miniaturized EDM (Electro Discharge Machining) device has been designed which is suitable to fixing on robot, and the whole system can motion mobile working. A novel control strategy of differential driving principle has been presented in order to solve the problem that electrode can't be revolved owing compact size has been resolved. Coaxial forced vibration of electrode is benefit for the evacuation of debris, and it helps to achieve stable and efficient machining. Analysis of harmonic response and the theoretical value of amplitude have been carried out. The optimal design of ultrasonic motor has been implemented using animate function of ANSYS and optimal design means, and the interference between teeth of stator has been avoided. Auto-frequency tracking has been completed, and electrode lateral vibration of electrode has been eliminated. Finally, the holes with figures of Φ85μm circle, Y have been machined.

The key of analyzing the light signal transmitting in fiber is the interaction and correlation between them. At present, we must consider the medium and the light field as one united system. Its strict physical theory is the quantum electrodynamics (QED), to process the light field and medium to second quantization. The quantum theory is considering both the medium and the light field as quantum wave function, so we can discuss the extreme limit frequency and distance. In the analyzing of extreme limit frequency, we can get it by considering two situations: the first is the photoelectric effect between light signal and fiber medium, the second is the transmission effect of high frequency incident light. In the analyzing of extreme limit of light signal distance, we will consider the interaction of the electron and the light field. We apply the theory and formula of scattering section. We analyze the colliding mechanism of particles in medium. We calculate the transmitting situation of photon energy according the energy and momentum reservation laws. According to the maximum frequency shift of light which is allowed by optical receiver, we can get the extreme limit distance of signal transmitting.

Data integration is a very important strategy to obtain optimum solutions in geo-scientific analysis, 3D scene modelling and visualization. This paper mainly focuses on the integration of GIS data, stereo aerial imagery and DSM to derive automatically tree rows and hedges in the open landscape. The roads, field boundaries, rivers and railways from GIS database also represent potential search areas for extracting tree rows and hedges, which are often located parallel and near to them. Different approaches, such as image segmentation by CIE L*a*b, edge extraction, linking, line grouping, space intersection and 3D verifying with DSM, are combined together to extract the objects of interest. The extracted information of tree rows and hedges can be used in many applications, such as deriving of wind erosion risk fields for soil monitoring and protection.

This paper describes an algorithm framework for registration of laser scanned range data and multiple overlap images. In our approach linear features were used for pose estimation. Many conjugate lines are automatically generated by extraction of linear primitives from images and laser data. The exterior orientation parameters of the images are calculated based on the theory and the arithmetic of the line photogrammetry, in which the conjugate lines are used as the observation values. The coplanar condition was used as error equation to resolve the external orientation parameter of digital image. In addition to the theoretical method, the paper presents a experimental analysis based on the quality of fit of final alignment between the LIDAR and digital cameras.

CAD-based photogrammetry methodologies have been used in object geometry inspection, and the 3D pose estimation of part is one of the important steps. This paper reports a strategy of 2D-3D pose estimation of sheet metal part by its CAD data and single grey image. It uses Hough strategy to get initial value and then do general point adjustment to get accuracy result. The strategy is tested with the images of some sheet metal parts. It is robust and reliable acting as initial values in certain condition. And it has been used in a sheet metal part inspection system.

A novel method to prepare nanomolds is reported, which is using multilayer thin-film deposition technique. A-Si/SiNx multilayer thin film is deposited on Si substrate in the conventional plasma enhanced chemical vapour deposition (PECVD) system. Then the relievo structure of alternative strips and grooves can be obtained on the cleaved cross-section of multilayer thin film by selective etching process. The strips of the etched sample have smooth and vertical sidewalls with small roughness. Due to the slow deposition rate, the thickness of the sublayer, therefore the size of the strips and grooves can be controlled on the nanometer scale by altering deposition time. The smallest width we get by now is the 20nm strips and 20nm grooves.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.