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2009

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Articles 2941 - 2970 of 4158

Full-Text Articles in Engineering

Nano-Switch For Study Of Gold Contact Behavior, Adam Fruehling, Shijun Xiao, Minghao Qi, Kaushik Roy, Dimitrios Peroulis Jan 2009

Nano-Switch For Study Of Gold Contact Behavior, Adam Fruehling, Shijun Xiao, Minghao Qi, Kaushik Roy, Dimitrios Peroulis

Birck and NCN Publications

In this paper we present the fabrication and characterization of a new NEMS DC switch as a vehicle to characterize Au-to-Au contacts at nano-scale. The switch consists of a 1050-nm long, 200-nm wide and 50-nm thick cantilever gold beam. The measured on-state resistance values range from 83 Omega to 640 Omega and the actuation voltages from 4 V to 22 V. All measurements are conducted at a current of 1 mu A and the obtained values are in good qualitative agreement with traditional elastic-plastic contact models. The calculated switching time is 55 ns. Characterization of contacts at nano-scale will be …

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Foreword For The Special Issue Of Selected Papers From The 1st Acm Sigspatial Workshop On Security And Privacy In Gis And Lbs, Elisa Bertino, Maria Luisa Damiani Jan 2009

Foreword For The Special Issue Of Selected Papers From The 1st Acm Sigspatial Workshop On Security And Privacy In Gis And Lbs, Elisa Bertino, Maria Luisa Damiani

Cyber Center Publications

The first Workshop on Security and Privacy in GIS and LBS (SPRINGL 2008) was organized on November 4, 2008 at Irvine (CA) in conjunction with the SIGSPATIAL International Conference on Advances in Geographic Information Systems (ACM GIS 2008). The goal of the SPRINGL workshop series is to provide a forum for researchers working in the area of geospatial data security and privacy. Both security and privacy are critical for geospatial applications because of the dramatic increase and dissemination of geospatial data in several application contexts including homeland security, environmental crises, and natural and industrial disasters. Furthermore, geospatial infrastructures are being …

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Stabilizing Nanostructured Materials By Coherent Nanotwins And Their Grain Boundary Triple Junction Drag, C Saldana, T G. Murthy, M R. Shankar, E A. Stach, S Chandrasekar Jan 2009

Stabilizing Nanostructured Materials By Coherent Nanotwins And Their Grain Boundary Triple Junction Drag, C Saldana, T G. Murthy, M R. Shankar, E A. Stach, S Chandrasekar

Birck and NCN Publications

The role of nanotwin lamellae in enhancing thermal stability of nanostructured materials is examined. Nanostructured copper with varying densities of twins was generated by controlling the deformation strain rate during severe plastic deformation at cryogenic temperatures. While the nanostructured materials produced under cryogenic conditions are characteristically unstable even at room temperatures, their stability is markedly improved when a dense dispersion of nanotwins is introduced. Observations of the role of nanotwins in pinning grain and subgrain structures suggest an interfacial engineering approach to enhancing the stability of nanostructured alloys.

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Identification Of Multiple Oscillation States Of Carbon Nanotube Tipped Cantilevers Interacting With Surfaces In Dynamic Atomic Force Microscopy, Mark Strus, Arvind Raman Jan 2009

Identification Of Multiple Oscillation States Of Carbon Nanotube Tipped Cantilevers Interacting With Surfaces In Dynamic Atomic Force Microscopy, Mark Strus, Arvind Raman

Birck and NCN Publications

Carbon nanotubes (CNTs) have gained increased interest in dynamic atomic force microscopy (dAFM) as sharp, flexible, conducting, nonreactive tips for high-resolution imaging, oxidation lithography, and electrostatic force microscopy. By means of theory and experiments we lay out a map of several distinct tapping mode AFM oscillation states for CNT tipped AFM cantilevers: namely, noncontact attractive regime oscillation, intermittent contact with CNT slipping or pinning, or permanent contact with the CNT in point or line contact with the surface while the cantilever oscillates with large amplitude. Each state represents fundamentally different origins of CNT-surface interactions, CNT tip-substrate dissipation, and phase contrast …

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Generalization Of Acid Properties, Brahim Medjahed, Mourad Ouzzani, Ahmed Elmagarmid Jan 2009

Generalization Of Acid Properties, Brahim Medjahed, Mourad Ouzzani, Ahmed Elmagarmid

Cyber Center Publications

ACID (Atomicity, Consistency, Isolation, and Durability) is a set of properties that guarantee the reliability of database transactions [2]. ACID properties were initially developed with traditional, business-oriented applications (e.g., banking) in mind. Hence, they do not fully support the functional and performance requirements of advanced database applications such as computer-aided design, computer-aided manufacturing, office automation, network management, multidatabases, and mobile databases. For instance, transactions in computer-aided design applications are generally of long duration and preserving the traditional ACID properties in such transactions would require locking resources for long periods of time. This has lead to the generalization of ACID properties …

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Orbital Start Effect And Quantum Confinement Transition Of Donors In Silicon, Rajib Rahman, G. P. Lansbergen, Seung H. Park, J. Verdujin, Gerhard Klimeck, S. Rogge, Lloyd C. L. Hollenberg Jan 2009

Orbital Start Effect And Quantum Confinement Transition Of Donors In Silicon, Rajib Rahman, G. P. Lansbergen, Seung H. Park, J. Verdujin, Gerhard Klimeck, S. Rogge, Lloyd C. L. Hollenberg

Birck and NCN Publications

Adiabatic shuttling of single impurity bound electrons to gate-induced surface states in semiconductors has attracted much attention in recent times, mostly in the context of solid-state quantum computer architecture. A recent transport spectroscopy experiment for the first time was able to probe the Stark shifted spectrum of a single donor in silicon buried close to a gate. Here, we present the full theoretical model involving large-scale quantum mechanical simulations that was used to compute the Stark shifted donor states in order to interpret the experimental data. Use of atomistic tight-binding technique on a domain of over a million atoms helped …

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Atomistic Full-Band Simulations Of Si Nanowire Transistors: Effects Of Electron-Phonon Scattering, Mathieu Luisier, Gerhard Klimeck Jan 2009

Atomistic Full-Band Simulations Of Si Nanowire Transistors: Effects Of Electron-Phonon Scattering, Mathieu Luisier, Gerhard Klimeck

Birck and NCN Publications

An atomistic full-band quantum transport simulator has been developed to study three-dimensional Si nanowire field-effect transistors (FETs) in the presence of electron-phonon scattering. The Non-equilibrium Green's Function (NEGF) formalism is solved in a nearest-neighbor sp(3)d(5)s* tight-binding basis. The scattering self-energies are derived in the self-consistent Born approximation to inelastically couple the full electron and phonon energy spectra. The band dispersion and the eigenmodes of the confined phonons are calculated using a dynamical matrix that includes the bond and angle deformations of the nanowires. The optimization of the numerical algorithms and the parallelization of the NEGF scheme enable the investigation of …

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Location Privacy In Moving-Object Environments, Dan Lin, Elisa Bertino, Reynold Cheng, Sunil Prabhakar Jan 2009

Location Privacy In Moving-Object Environments, Dan Lin, Elisa Bertino, Reynold Cheng, Sunil Prabhakar

Cyber Center Publications

The expanding use of location-based services has profound implications on the privacy of personal information. If no adequate protection is adopted, information about movements of specific individuals could be disclosed to unauthorized subjects or organizations, thus resulting in privacy breaches. In this paper, we propose a framework for preserving location privacy in moving-object environments. Our approach is based on the idea of sending to the service provider suitably modified location information. Such modifications, that include transformations like scaling, are performed by agents interposed between users and service providers. Agents execute data transformation and the service provider directly processes the transformed …

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A Stochastic Collocation Approach To Bayesian Inference In Inverse Problems, Youssef Marzouk, Dongbin Xiu Jan 2009

A Stochastic Collocation Approach To Bayesian Inference In Inverse Problems, Youssef Marzouk, Dongbin Xiu

PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems

We present an efficient numerical strategy for the Bayesian solution of inverse problems. Stochastic collocation methods, based on generalized polynomial chaos (gPC), are used to construct a polynomial approximation of the forward solution over the support of the prior distribution. This approximation then defines a surrogate posterior probability density that can be evaluated repeatedly at minimal computational cost. The ability to simulate a large number of samples from the posterior distribution results in very accurate estimates of the inverse solution and its associated uncertainty. Combined with high accuracy of the gPC-based forward solver, the new algorithm can provide great efficiency …

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Coarse Grain Modeling Of Spall Failure In Molecular Crystals: Role Of Intra-Molecular Degrees Of Freedom, Karen Lynch, Alexander Thompson, Alejandro Strachan Jan 2009

Coarse Grain Modeling Of Spall Failure In Molecular Crystals: Role Of Intra-Molecular Degrees Of Freedom, Karen Lynch, Alexander Thompson, Alejandro Strachan

PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems

We use a recently developed thermodynamically accurate mesodynamical method (Strachan and Holian 2005 Phys. Rev. Lett. 94 014301) where groups of atoms are represented by mesoparticles to characterize the shock compression and dynamical failure (spall) of a model molecular crystal. We characterize how the temperature rise caused by the shockwave depends on the specific heat of the degrees of freedom (DoFs) internal to the mesoparticles (Cint) and the strength of the coupling between the internal DoFs and the mesoparticles. We find that the temperature of the shocked material decreases with increasing Cint and decreasing coupling and quantify these effects. Our …

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A Generalized Polynomial Chaos Based Ensemble Kalman Filter, Jia Li, Dongbin Xiu Jan 2009

A Generalized Polynomial Chaos Based Ensemble Kalman Filter, Jia Li, Dongbin Xiu

PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems

As one of the most adopted sequential data assimilation methods in many areas, especially those involving complex nonlinear dynamics, the ensemble Kalman filter (EnKF) has been under extensive investigation regarding its properties and efficiency. Compared to other variants of the Kalman filter (KF), EnKF is straightforward to implement, as it employs random ensembles to represent solution states. This, however, introduces sampling errors that affect the accuracy of EnKF in a negative manner. Though sampling errors can be easily reduced by using a large number of samples, in practice this is undesirable as each ensemble member is a solution of the …

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Private Queries And Trajectory Anonymization: A Dual Perspective On Location Privacy, Gabriel Ghinita Jan 2009

Private Queries And Trajectory Anonymization: A Dual Perspective On Location Privacy, Gabriel Ghinita

Cyber Center Publications

The emergence of mobile devices with Internet connectivity (e.g., Wi-Fi) and global positioning capabilities (e.g., GPS) have triggered the widespread development of location-based applications. For instance, users are able to ask queries about points of interest in their proximity. Furthermore, users can act as mobile sensors to monitor traffic flow, or levels of air pollution. However, such applications require users to disclose their locations, which raises serious privacy concerns. With knowledge of user locations, a malicious attacker can infer sensitive information, such as alternative lifestyles or political affiliations. Preserving location privacy is an essential requirement towards the successful deployment of …

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Advancing Nanoelectronic Device Modeling Through Peta-Scale Computing And Deployment On Nanohub, Benjamin Haley, Sunhee Lee, Mathieu Luisier, Hoon Ryu, Faisal Saied, Steven Clark, Hansang Bae, Gerhard Klimeck Jan 2009

Advancing Nanoelectronic Device Modeling Through Peta-Scale Computing And Deployment On Nanohub, Benjamin Haley, Sunhee Lee, Mathieu Luisier, Hoon Ryu, Faisal Saied, Steven Clark, Hansang Bae, Gerhard Klimeck

Birck and NCN Publications

Recent improvements to existing HPC codes NEMO 3-D and OMEN, combined with access to peta-scale computing resources, have enabled realistic device engineering simulations that were previously infeasible. NEMO 3-D can now simulate 1 billion atom systems, and, using 3D spatial decomposition, scale to 32768 cores. Simulation time for the band structure of an experimental P doped Si quantum computing device fell from 40 minutes to I minute. OMEN can perform fully quantum mechanical transport calculations for real-word UTB FETs on 147,456 cores in roughly 5 minutes. Both of these tools power simulation engines on the nanoHUB, giving the community access …

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Query Mesh: Multiroute, Rimma Nehme, Karen Works, Elke Rundensteiner, Elisa Bertino Jan 2009

Query Mesh: Multiroute, Rimma Nehme, Karen Works, Elke Rundensteiner, Elisa Bertino

Cyber Center Publications

We propose to demonstrate a practical alternative approach to the current state-of-the-art query processing techniques, called the “Query Mesh” (or QM, for short). The main idea of QM is to compute multiple routes (i.e., query plans)1, each designed for a particular subset of data with distinct statistical properties. Based on the execution routes and the data characteristics, a classifier model is induced and is used to partition new data tuples to assign the best routes for their processing. We propose to demonstrate the QM framework in the streaming context using our demo application, called the “Ubi-City”. We will illustrate the …

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Parallel Reactive Molecular Dynamics: Numerical Methods And Algorithmic Techniques, Hasan Metin Aktulga, Joseph C. Fogarty, Sagar A. Pandit, Ananth Y. Grama Jan 2009

Parallel Reactive Molecular Dynamics: Numerical Methods And Algorithmic Techniques, Hasan Metin Aktulga, Joseph C. Fogarty, Sagar A. Pandit, Ananth Y. Grama

PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems

No abstract provided.

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A Hierarchical Approach To Model Web Query Interfaces For Web Source Integration, Thomas Kabisch, Eduard Dragut, Clement Yu, Ulf Leser Jan 2009

A Hierarchical Approach To Model Web Query Interfaces For Web Source Integration, Thomas Kabisch, Eduard Dragut, Clement Yu, Ulf Leser

Cyber Center Publications

Much data in the Web is hidden behind Web query interfaces. In most cases the only means to "surface" the content of a Web database is by formulating complex queries on such interfaces. Applications such as Deep Web crawling and Web database integration require an automatic usage of these interfaces. Therefore, an important problem to be addressed is the automatic extraction of query interfaces into an appropriate model. We hypothesize the existence of a set of domain-independent "commonsense design rules" that guides the creation of Web query interfaces. These rules transform query interfaces into schema trees. In this paper we …

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The Plant Ionome Coming Into Focus, Lorraine Williams, David Salt Jan 2009

The Plant Ionome Coming Into Focus, Lorraine Williams, David Salt

Cyber Center Publications

92 elements have been identified on earth and 17 of these are known to be essential to all plants. The essential elements required in relatively large amounts (>0.1% of dry mass) are called macronutrients and include C, H, O, N, S, P, Ca, K, Mg. Those required in much smaller amounts (<0.01% of dry mass) are referred to as micronutrients or trace elements and include Ni, Mo, Cu, Zn, Mn, B, Fe, and Cl. Plant growth and development depends on a balanced supply of these essential elements and thus the plant has a range of homeostatic mechanisms operating to ensure that this is maintained. Beneficial elements which promote growth and may be essential to some taxa, include Na, Co, Al, Se and Si. Elements such as the heavy metal Cd and the metalloid As have no demonstrated biological function in plants, but are nevertheless taken up and cause severe toxicity in most plant species. The concept for this special issue is the plant ionome, a word coined to encompass all these elements and allow focussed discussion and investigations on the mechanisms that co-ordinately regulate these elements in response to genetic and environmental factors reviewed in Salt et al., 2008).

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Gold Nanorods As Contrast Agents For Biological Imaging: Optical Properties, Surface Conjugation And Photothermal Effects, Ling Tong, Qingshan Wei, Alexander Wei, Ji-Xin Cheng Jan 2009

Gold Nanorods As Contrast Agents For Biological Imaging: Optical Properties, Surface Conjugation And Photothermal Effects, Ling Tong, Qingshan Wei, Alexander Wei, Ji-Xin Cheng

Other Nanotechnology Publications

Gold nanorods (NRs) have plasmon-resonant absorption and scattering in the near-infrared (NIR) region, making them attractive probes for in vitro and in vivo imaging. In the cellular environment, NRs can provide scattering contrast for darkfield microscopy, or emit a strong two-photon luminescence due to plasmon-enhanced two-photon absorption. NRs have also been employed in biomedical imaging modalities such as optical coherence tomography or photoacoustic tomography. Careful control over surface chemistry enhances the capacity of NRs as biological imaging agents by enabling cell-specific targeting, and by increasing their dispersion stability and circulation lifetimes. NRs can also efficiently convert optical energy into heat, …

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Beyond K-Anonymity: A Decision Theoretic Framework For Assessing Privacy Risk, Guy Lebanon, Monica Scannapieco, Mohamed Fouad, Elisa Bertino Jan 2009

Beyond K-Anonymity: A Decision Theoretic Framework For Assessing Privacy Risk, Guy Lebanon, Monica Scannapieco, Mohamed Fouad, Elisa Bertino

Cyber Center Publications

An important issue any organization or individual has to face when managing data containing sensitive information, is the risk that can be incurred when releasing such data. Even though data may be sanitized before being released, it is still possible for an adversary to reconstruct the original data using additional information thus resulting in privacy violations. To date, however, a systematic approach to quantify such risks is not available. In this paper we develop a framework, based on statistical decision theory, that assesses the relationship between the disclosed data and the resulting privacy risk. We model the problem of deciding …

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Defining A Forensic Audit, G. S. Smith, D. L. Crumbley Jan 2009

Defining A Forensic Audit, G. S. Smith, D. L. Crumbley

Journal of Digital Forensics, Security and Law

Disclosures about new financial frauds and scandals are continually appearing in the press. As a consequence, the accounting profession's traditional methods of monitoring corporate financial activities are under intense scrutiny. At the same time, there is recognition that principles-based GAAP from the International Accounting Standards Board will become the recognized standard in the U.S. The authors argue that these two factors will change the practices used to fight corporate malfeasance as investigators adapt the techniques of accounting into a forensic audit engagement model.

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Visualisation Of Honeypot Data Using Graphviz And Afterglow, Craig Valli Jan 2009

Visualisation Of Honeypot Data Using Graphviz And Afterglow, Craig Valli

Journal of Digital Forensics, Security and Law

This research in progress paper explores the use of Graphviz and Afterglow for the analysis of data emanating from a honeypot system. Honeypot systems gather a wide range of data that is often difficult to readily search for patterns and trends using conventional log file analysis techniques. The data from the honeypots has been statically extracted and processed through Afterglow scripts to produce inputs suitable for use by the DOT graph based tools contained within Graphviz. This paper explores some of the benefits and drawbacks of currently using this type of approach.

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Digital Camera Photographing In Measuring Propagation Loss Properties Of Ion2exchange Planar Optical Waveguides, Ling-Hua Jia, Feng Qiu, Jian Ying, Ti Yun-Jiang, Jie Z|Heng, Pengfei Wang, Gerald Farrell Jan 2009

Digital Camera Photographing In Measuring Propagation Loss Properties Of Ion2exchange Planar Optical Waveguides, Ling-Hua Jia, Feng Qiu, Jian Ying, Ti Yun-Jiang, Jie Z|Heng, Pengfei Wang, Gerald Farrell

Articles

The digital photographs of propagation lines of ion-exchange planar glass optical waveguides were taken by a common digital camera.According to the profile of light intensity of propagation lines,the attenuation curves were fitted and the propagation losses of the waveguides were calculated.The waveguides were treated by annealing process,and propagation losses properties were studied before and after annealing,respectively.The results show that the loss of waveguide increases with the mode.The loss in 0 mode decreases from 2.148 9 dB·cm－1 to 0.746 0 dB·cm－1.

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Misalignment Limits For A Singlemode-Multimode-Singlemode Fiber-Based Edge Filter, Agus Hatta, Gerald Farrell, Pengfei Wang, Ginu Rajan, Yuliya Semenova Jan 2009

Misalignment Limits For A Singlemode-Multimode-Singlemode Fiber-Based Edge Filter, Agus Hatta, Gerald Farrell, Pengfei Wang, Ginu Rajan, Yuliya Semenova

Articles

Misalignment effects on the spectral characteristics of edge filters based on singlemode–multimode–singlemode (SMS) fibre structures are investigated numerically and experimentally. A modal propagation analysis is used with a set of guided modes calculated using the finite-difference method to determine the transmission loss of the SMS-based edge filters. A limit for the tolerable misalignment of the SMS fiber-based edge filter is proposed, beyond which the spectral performance of the SMS structure degrades unacceptably. The numerical results are verified experimentally with good agreement.

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Universities Changing In Response To A Volatile Environment: A Case Study From Ireland, Kevin Kelly Jan 2009

Universities Changing In Response To A Volatile Environment: A Case Study From Ireland, Kevin Kelly

Books/Book chapters

This paper is a short summary of a research thesis submitted for a doctoral degree in education in late 2008. The substantive issue investigated was the response of a large higher education institute (HEI) in Ireland, the Dublin Institute of Technology and hereafter referred to as the Institute, to the demands for change. The research was undertaken by an experienced academic from inside the organisation. What is happening in this institute may be significant to others because change in higher education is a key debate throughout the world at present. The research study shows that stakeholders in the Institute acknowledge …

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Genetic Stigmergy: Framework And Applications, Joshua A. Brandoff Jan 2009

Genetic Stigmergy: Framework And Applications, Joshua A. Brandoff

Graduate Dissertations and Theses

Stigmergy has long been studied and recognized as an effective system for self-organization among social insects. Through the use of chemical agents known as pheromones, insect colonies are capable of complex collective behavior often beyond the scope of an individual agent. In an effort to develop human-made systems with the same robustness, scientists have created artificial analogues of pheromone-based stigmergy, but these systems often suffer from scalability and complexity issues due to the problems associated with mimicking the physics of pheromone diffusion. In this thesis, an alternative stigmergic framework called 'Genetic Stigmergy' is introduced. Using this framework, agents can indirectly …

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Optical Properties Of Coal Combustion Byproducts For Particle-Size Analysis By Laser Diffraction, Robert B. Jewell, Robert F. Rathbone Jan 2009

Optical Properties Of Coal Combustion Byproducts For Particle-Size Analysis By Laser Diffraction, Robert B. Jewell, Robert F. Rathbone

Coal Combustion and Gasification Products Journal Archive

Laser diffraction analysis is commonly used for determining the particle-size distribution (PSD) of fly ash. However, there is currently no standard method for preparing samples and analyzing them. The Mie and Fraunhofer optical models are used to calculate the PSD of fly ash from laser diffraction data. The Mie theory is most applicable for particles smaller than 50 mm, and is therefore the most accurate model for the analysis of fly ash. However, the refractive index (RI) of fly ash is complex and not well known. This study presents the analysis of several supplementary cementitious materials (SCMs) such as coal …

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Theia: Radio Frequency Identification Performance Analysis Tool, Jason Francis Pereira Jan 2009

Theia: Radio Frequency Identification Performance Analysis Tool, Jason Francis Pereira

Electrical Engineering Theses - Archive

In recent years there has been an increase in the adoption of Radio FrequencyIdentication or RFID systems for most applications that deal with investment (products/people) tracking. The ideal requirements of investment tracking systems are :-lost-cost, zero maintenance and eciency.Although the applications are similar in nature, the scenarios and operating environmentsare not. This is a problem that plagues an inexpert consumer of RFIDsystems. RFID systems are application specic and hence have to be properly customizedto the application environment. One solution to this problem is to have theinstallation set up by an expert, but this is impractical due to recurring costs for …

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Implementation Of Autonomous Navigation And Obstacle Avoidance On An Unmanned Ground Vehicle, Pranav Naresh Desai Jan 2009

Implementation Of Autonomous Navigation And Obstacle Avoidance On An Unmanned Ground Vehicle, Pranav Naresh Desai

Electrical Engineering Theses - Archive

This thesis presents the implementation of a novel distributed embedded systems approach to real-time obstacle avoidance and guidance for an Unmanned Ground Vehicle (UGV). The mobility, real-time, and limited size requirements of UGVs, result in computationally limited and resource constrained hardware platform. The use of distributed computational resources, such as multiple embedded micro-controllers, enables the distribution of the computing resources for obstacle avoidance and guidance system functionalities. The resulting system's complexity is significantly greater than that of a single high performance processor performing all of the above functions. The hardware platform is integrated with sensors and micro-controllers to function as …

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Design And Study Of Phase Locked Loop For Space Applications In Sub-Micron Cmos Technology, Partha Pratim Ghosh Jan 2009

Design And Study Of Phase Locked Loop For Space Applications In Sub-Micron Cmos Technology, Partha Pratim Ghosh

Electrical Engineering Dissertations - Archive

This work proposes a successful design of a radiation hard phase locked loop (PLL) using Silicon-on-Sapphire CMOS (SOS) technology for space applications. A fully self-bias radiation hard PLL providing frequency of 2.5 GHz has been designed for the first time on SOS technology. SOS technology is used to provide radiation hardness from Single Event Effects (SEE), an improvement over the use of commercially available bulk CMOS process. Innovative designs of VCO implemented in the PLL, architectural modifications in the use of buffers, bias stages, asynchronous dividers and optimization of fully self-bias design provide hardness from Total Ionization Dose (TID). Self-bias …

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Designing Multi-Objective Reverse Logistics Networks Using Genetic Algorithms, Sanya Yimsiri Jan 2009

Designing Multi-Objective Reverse Logistics Networks Using Genetic Algorithms, Sanya Yimsiri

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Reverse logistics (RL) involves management of activities that include collection, sort/storage, transportation, recovery, disposal and re-distribution. The product return process is more complicated than forward logistics due to presence of multiple reverse distribution channels, individualized returns with small quantities, extended order cycles associated with product exchanges and a variety of recovery and disposition options. Reverse logistics has been gaining interest from many sectors due to rising costs, environmental concern and tougher regulations. As a result, good reverse logistics network design can help business save costs and meet their bottom lines in this competitive global environment. Most of the previous research …

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