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As Engineering Change Order (ECO) has attracted substantial attention in modern VLSI design, the open net problem, which aims at constructing a shortest obstacle-avoiding path to reconnect the net shapes in an open net, becomes more critical in the ECO stage. This paper addresses a multi-layer obstacle-avoiding region-to-region Steiner minimal tree (SMT) construction problem that connects all net shapes by edges on a layer or vias between layers, and avoids running through any obstacle with a minimal total cost. Existing multi-layer obstacle-avoiding SMT algorithms consider pin-to-pin connections instead of region-to-region ones, which would limit the solution quality due to its lacking region information. In this paper, we present an efficient algorithm based on our new multi-layer obstacle-avoiding region-to-region spanning graph to solve the addressed problem, which guarantees to find an optimal solution for a net connecting two regions on a single layer. Experimental results show that our algorithm outperforms all the participating routers of the 2017 CAD Contest at ICCAD in both solution quality and runtime. [ABSTRACT FROM AUTHOR]

In this paper, a four-layer submerged horizontal porous plate breakwater was proposed, and its wave-dissipating performance was examined experimentally in a wave flume. The design of the geometrical parameters (i.e., submerged depth and plate porosity) is discussed. The experimental results of concerned characteristics in engineering practice (i.e., the effect of layer quantity, plate width, porosity, and submerged depth) are shown and discussed. A relatively larger plate width or a smaller porosity of the upper plate may benefit the wave-dissipating performance, and larger layer depths may increase the wave transmission. Generally, the fourlayer breakwater proposed in the present paper shows satisfactory performance under a wide range of incident wave lengths and has promising application future in coastal engineering. [ABSTRACT FROM AUTHOR]

This work aims to propose a general global router that is easily extendable to multi-objective global routing case. The proposed router uses a maze routing based spanning tree generation algorithm to build an initial solution. The initial solution is optimized using a Simulated Evolution (SimE)-based algorithm. The spanning tree generation algorithm can be used in any layout model (with or without obstacles). The SimE-based optimization algorithm uses selection and allocation operations to optimize the initial solution. The SimE-based optimization is extendable to multi-objective case. In the experiments, the proposed algorithm successfully solved all the test problems in the ISPD'98 suite that comprises of industrial problems. [ABSTRACT FROM PUBLISHER]

A multi-layer Low temperature superconducting (LTS) Microstrip K-band diplexer is designed, fabricated, measured and reported for the first time. The Chebyshev K-band filters used in the device have five poles and are designed for the center frequencies of 20.45 GHz and 21.15 GHz with a bandwidth of 500 MHz. The dimension of the fabricated diplexer including the input and output Coplanar Waveguide (CPW) to microstrip transitions is only 3.2 mm × 2.2 mm. The diplexer is measured in an RF cryogenic probe station at 4K. A novel frequency independent broadband 50 Ω load is designed with the same fabrication process and used to match one of the three ports when the other two ports are being measured. Simulation and measured results of the diplexer show a spurious-free response up to 40GHz. [ABSTRACT FROM PUBLISHER]

One of the important objectives of every telecommunication operator, when designing an optical network, is to provide a satisfying quality of service in the most cost-effective way to the final customer. As every network is frequently exposed to many different threats causing network disruptions, network recovery is the prime capability needed to achieve this objective. After a brief introduction on the existing reactive recovery methods we present a new method of proactive detection and explain how the method can be applied to some recovery schemes and discuss its benefits. [ABSTRACT FROM PUBLISHER]

The article contains report on fabrication of multi-layer microstructures that takes the advantage of electroosmosis to mix fluids. Microlaboratories for biochemical applications often require rapid mixing of different fluid streams. At the microscale, flow is usually highly ordered laminar flow and the lack of turbulence makes diffusion the primary mechanism for mixing. While diffusional mixing of small molecules can occur in a matter of seconds over distances of tens of micrometers, mixing of larger molecules such as peptides, proteins, and high molecular-weight nucleic acids can require equilibration times from minutes to hours over comparable distances. Such delays are impractically long for many chemical analyses. These problems have led to an intense search for more efficient mixers for microfluidic systems most microscale mixing devices are either passive mixers that use geometrical stirring or active mixers that use moving parts or external forces, such as pressure or electric field. In a passive mixer, one way of increasing the mixing is by “shredding” two or several fluids into very thin alternating layers, which decreases the average diffusion length for the molecules between the different fluids. Another way of improving mixing efficiency is to use active mixers with moving parts that stir the fluids. At the microscale level moving parts in an active mixer are very fragile. One alternative solution which we explored is to use electroosmotic effects to achieve a mixing effect that is perpendicular to the main direction of the flow. [ABSTRACT FROM PUBLISHER]

During the sudden catastrophic events that have occurred in this last decade, social media have proven their importance in the creation and management of ad-hoc crisis communities. These platforms are increasingly used as complementary support tools for conventional crisis management teams. Recent disasters (e.g. Haiti, Australia, Japan, Mexico, etc.) have demonstrated their real potential in providing support to emergency operations for crisis management. However, several questions remain unanswered regarding the efficiency of their usage and especially their integration into the conventional information collection systems (technological sensors, cameras, SMS, etc.) usually used for crisis mapping. This paper aims to present multi-layer crisis mapping using a social media-based approach. We propose a generic step-by-step methodology as an integrated approach that connects a set of needs to a set of appropriate responses. The concept presented in this paper is the need/solution matrix, which plays a key role in the design of a multi-layer crisis map. The paper ends with an experiment with the well-known Twitter microblogging platform. [ABSTRACT FROM PUBLISHER]

Even though software-defined networking (SDN) and the OpenFlow protocol have demonstrated great practicality in the packet domain, there has been some hesitance in extending the OpenFlow specification to circuit and optical switched domains that constitute wide area multi-layer transport networks. This paper presents an overview of various proposals with regards to extending OpenFlow to support circuit switched multi-layer networks. The goal is to shed light on these ideas and propose a way forward. This paper favors a top-down approach, which relies on transport network's main SDN use case: packet-optical integration, to help identify the sufficient extensions for OpenFlow to support circuit/optical switching. [ABSTRACT FROM PUBLISHER]

This paper introduces a User-Controllable MultiLayer Secure Algorithm (UMSA) to authenticate the MANET nodes before joining an existing MANET or formation of a new MANET by using the information from the user, the application layer, the network layer and the data-link layer. Currently, the authentication and the routing of the MANET nodes are two distinct processes. The proposed UMSA aims to embed the security information into the routing algorithm, thus combining the authentication and routing processes without incurring significant overheads. The MANET nodes are only allowed to form a MANET if the nodes are identified with a unique User-Controllable Identification, running users' pre-agreed application(s), and are in the list of permitted nodes, thus saving resources in the nodes by maintaining a smaller routing information. The experimental results show that the UMSA enhances the security of the MANET without negatively impacting the performance of the routing algorithm. [ABSTRACT FROM PUBLISHER]

Even though vertical 3D integration offers increased device density, reduced signal delay, and design flexibility, heat and thermal concerns are, nevertheless, aggravated. In this context, accurate computation of temperature profile is required to establish thermal design rules governing the feasibility of integration options. Within this framework, a novel methodology based on discontinuous Galerkin finite element method for accurate thermal profile estimation of 3D integrated circuits is proposed§. The method is utilized to simulate geometrically complicated physical structures with limited complexity overhead. [ABSTRACT FROM PUBLISHER]

This paper presents a Hybrid Multi-Layer Feedforward Neural Network (HMLFNN) technique for predicting the output from a Grid-Connected Photovoltaic (GCPV) system. In the proposed HMLFNN, Fast Evolutionary Programming (FEP) was employed to optimize the training process of the Multi-Layer Feedforward Neural Network (MLFNN). FEP was used to select the optimal values for the number of neurons in the hidden layer, the learning rate, the momentum rate, the type of activation function and the learning algorithm. In addition, the MLFNN utilized solar irradiance (SI) and module temperature (MT) as its inputs and AC kWh energy as its output. When compared with the Classical Evolutionary Programming (CEP) trained MLFNN, the proposed FEP-based HMLFNN offered superior performance by producing lower computation time and lower prediction error. [ABSTRACT FROM PUBLISHER]

Metallic nanocomposite material is widely used in Surface Plasmon Rsesonance (SPR) due to its high stability and special optical features which enhance the Surface Enhanced Ramon Scattering (SERS) effect. A novel multi-layered Au-dielectric core-shell structural SERS substrate is proposed. Finite Elment Analysis (FEA) simulation shows multi-layer shell-core nanosphere (SiO2@Au, SiO2@Au@SiO2…) can improve Local Field Enhancement (LFE), comparing to Au single-layer nanosphere. That is because multi-layer nanoshpere exists intra-layer coupling besides cavity coupling. Moreover, red-shift can be observed via tuning the thickness of multi-layer nanospheres, which is greatly beneficial to biological detection in near infrared region (NIR). Lastly, these multi-layer nanospheres are synthesised by liquid phase reduction. And high absorbance and red-shift effect are verified with UV-vis absorption spectrum. [ABSTRACT FROM PUBLISHER]

In this paper we present a solution for providing protection in a Ethernet based access and metro network. To accomplish this we targeted two issues, protection aimed path computation in networks which does not provide fully disjoint paths, and the design and implementation of bi-directional forward detection (BFD) protocol in a GMPLS controlled Ethernet network. To the best of our knowledge, neither issue has been previously addressed through a similar approach and is therefore to be considered novel in its design and implementation. Our implementation shows good performances and reliability in both performance testing and testbed experiments. [ABSTRACT FROM PUBLISHER]

The near surface area of forging dies is exposed to high mechanical loads. Additionally thermal and chemical stresses occur during the forging process. Depending on the number of forged parts, several kinds of damage develop in the surface area, which lead to failures of forging dies. Die wear is the main reason of failure with a 70% ratio. The abrasion resistance of the surface area of forging dies has to be increased in order to reduce wear. Therefore different methods were examined such as the increase of the abrasion resistance by plasma nitriding and by coating with ceramic layers (TiN, TiCN, TiC, CrN). These layers are applied to the forging die by using PACVD or PAPVD treatment. At the Institute of Metal Forming and Metal-Forming Machines of the University of Hanover a wear reduction by factor 3.5 compared to nitrided forging dies for forging helical gears was achieved. This was possible by using a coating compound of 18 ceramic layers. These excellent results for the multilayer system can be explained through the energy reduction at the inner boundaries and a crack deflection effect at the phase transitions. The layer support of neighboring layers and a stress relaxation through the stacked construction of the layer system are also improving the durability of the coating. This multilayer coating consists of a TiN-TiCN-TiC layer system with an overall thickness of 1.8 μm. This paper presents investigations of this multilayer compound and further research to reduce wear through an additional TiBN coating layer. With this additional top coating an increase of the thermal resistance and the oxidation resistance can be achieved. As a result of this enhancement a further increase of the wear reduction was expected. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Many actuator applications require high resolution, accuracy and fast response time. Piezoelectric multi-layer actuators are used for such applications to manage displacements from nanometer to micrometer range and the response time in microseconds at comparatively low drive voltages. This paper deals with the characterization of lead zirconate titanate (PZT) ceramic multilayer actuators fabricated by tape casting method utilizing impedance analysis and strain measurements. Width mode resonance frequency is predicted using finite element analysis. The electrical impedance spectrums in the frequency range 100 kHz to 250 kHz of PZT multilayers show a small change in resonant behavior. Possible reasons for this change are discussed. Presence of defect in the multi-layer actuator is validated by optical microscopy. The results also show the displacement response at 75V of defect free PZT multilayer actuator. [ABSTRACT FROM PUBLISHER]