Showing papers on "Modular design published in 2004"

Modularity from fluctuations in random graphs and complex networks.

Abstract: The mechanisms by which modularity emerges in complex networks are not well understood but recent reports have suggested that modularity may arise from evolutionary selection. We show that finding the modularity of a network is analogous to finding the ground-state energy of a spin system. Moreover, we demonstrate that, due to fluctuations, stochastic network models give rise to modular networks. Specifically, we show both numerically and analytically that random graphs and scale-free networks have modularity. We argue that this fact must be taken into consideration to define statistically significant modularity in complex networks.

PSRCHIVE and PSRFITS: An Open Approach to Radio Pulsar Data Storage and Analysis

Abstract: A new set of software applications and libraries for use in the archival and analysis of pulsar astronomical data is introduced. Known collectively as the psrchive scheme, the code was developed in parallel with a new data storage format called psrfits, which is based on the Flexible Image Transport System (FITS). Both of these projects utilise a modular, object-oriented design philosophy. psrchive is an open source development environment that incorporates an extensive range of c++ object classes and pre-built command line and graphical utilities. These deal transparently and simultaneously with multiple data storage formats, thereby enhancing data portability and facilitating the adoption of the psrfits file format. Here, data are stored in a series of modular header-data units that provide flexibility and scope for future expansion. As it is based on FITS, various standard libraries and applications may be used for data input, output, and visualisation. Both psrchive and psrfits are made publicly available to the academic community in the hope that this will promote their widespread use and acceptance.

Sphinx-4: a flexible open source framework for speech recognition

Abstract: Sphinx-4 is a flexible, modular and pluggable framework to help foster new innovations in the core research of hidden Markov model (HMM) speech recognition systems. The design of Sphinx-4 is based on patterns that have emerged from the design of past systems as well as new requirements based on areas that researchers currently want to explore. To exercise this framework, and to provide researchers with a "researchready" system, Sphinx-4 also includes several implementations of both simple and state-of-the-art techniques. The framework and the implementations are all freely available via open source.

System, architecture, and method for logical server and other network devices in a dynamically configurable multi-server network environment

Abstract: Network architecture, computer system and/or server, circuit, device, apparatus, method, and computer program and control mechanism for managing power consumption and workload in computer system and data and information servers. Further provides power and energy consumption and workload management and control systems and architectures for high-density and modular multi-server computer systems that maintain performance while conserving energy and method for power management and workload management. Dynamic server power management and optional dynamic workload management for multi-server environments is provided by aspects of the invention. Modular network devices and integrated server system, including modular servers, management units, switches and switching fabrics, modular power supplies and modular fans and a special backplane architecture are provided as well as dynamically reconfigurable multi-purpose modules and servers. Backplane architecture, structure, and method that has no active components and separate power supply lines and protection to provide high reliability in server environment.

Modular ATRON: modules for a self-reconfigurable robot

Abstract: This paper describes the mechanical and electrical design of a new lattice based self-reconfigurable robot, called the ATRON. The ATRON system consists of several fully self-contained robot modules, each having their own processing power, power supply, sensors and actuators. The ATRON modules are roughly spheres with equatorial rotation. Each module can be connected to up to eight neighbors through four male and four female connectors. In this paper, we describe the realization of the design, both the mechanics and the electronics. Details on power sharing and power consumption is given. Finally, this paper includes a brief outline of our future work on the ATRON system.

Measuring modularity-based manufacturing practices and their impact on mass customization capability: a customer-driven perspective

Abstract: As uncertainty in markets and technology intensifies, more companies are adopting modular product and process architectures to cope with increasing demands for individually customized products. Modularity-based manufacturing is the application of unit standardization or substitution principles to create modular components and processes that can be configured into a wide range of end products to meet specific customer needs. This study defines modularity-based manufacturing practices (MBMP), develops a valid and reliable instrument to measure MBMP, builds a framework that relates customer closeness, MBMP, and mass customization capability, and tests structural relationships within this framework using LISREL. Based on 303 responses from members of the Society of Manufacturing Engineers, statistically significant and positive relationships were found among customer closeness, modularity-based manufacturing practices, and mass customization capability. Managerial implications of the empirical findings of this study and future research directions are also discussed.

Product modularity: measures and design methods

Abstract: This paper presents an overview of existing research on measures of product modularity and methods to achieve modularity in product design Discussions of the development of modular products have increased in recent years The research activity into the development of modularity measures and methods has also increased These measures and methods vary considerably in purpose and process Some are highly quantitative and some are completely qualitative Some are information intensive and some are more easily applied The relationship to product platform planning is also shown This overview shows no clear consensus beyond those found in the definition of modularity There are, however, several themes that are prevalent Most measures center on measuring dependencies with components external to modules Some measures include a measure of component similarity However, what is measured as dependencies and similarities varies by measure and by context Additionally, there is always some subjectivity in the mea

Technical note: The Modular Earth Submodel System (MESSy) - a new approach towards Earth System Modeling

Abstract: The development of a comprehensive Earth System Model (ESM) to study the interactions between chemical, physical, and biological processes, requires coupling of the different domains (land, ocean, atmosphere, ...). One strategy is to link existing domain-specific models with a universal coupler, i.e. an independent standalone program organizing the communication between other programs. In many cases, however, a much simpler approach is more feasible. We have developed the Modular Earth Submodel System (MESSy). It comprises (1) a modular interface structure to connect to a , (2) an extendable set of such for miscellaneous processes, and (3) a coding standard. MESSy is therefore not a coupler in the classical sense, but exchanges data between a and several within one comprehensive executable. The internal complexity of the is controllable in a transparent and user friendly way. This provides remarkable new possibilities to study feedback mechanisms (by two-way coupling). Note that the MESSy and the coupler approach can be combined. For instance, an atmospheric model implemented according to the MESSy standard could easily be coupled to an ocean model by means of an external coupler. The vision is to ultimately form a comprehensive ESM which includes a large set of submodels, and a base model which contains only a central clock and runtime control. This can be reached stepwise, since each process can be included independently. Starting from an existing model, process submodels can be reimplemented according to the MESSy standard. This procedure guarantees the availability of a state-of-the-art model for scientific applications at any time of the development. In principle, MESSy can be implemented into any kind of model, either global or regional. So far, the MESSy concept has been applied to the general circulation model ECHAM5 and a number of process boxmodels.

Crystallography of Modular Materials

Abstract: 1. Modular series - principles and types 2. Ordered derivative structures 3. Polytypes and polytype categories 4. Application of modularity to structure description and modelling 5. Modularity at crystal scale - twinning

Modeling and analysis of multiconverter DC power electronic systems using the generalized state-space averaging method

Abstract: This paper presents a modular approach for the modeling and simulation of multiconverter DC power electronic systems based on the generalized state-space averaging method. These systems may consist of many individual converters connected together to form large and complex systems. In addition to simplifying the analysis procedure, by using the proposed method, the time step for analysis of the system can be increased. Therefore, the required computation time and computer memory for complex systems can be reduced considerably. In this paper, after introducing the proposed approach, results of applying the method to a representative system are presented.

Modularity and Relevance: How Can a Massively Modular Mind Be Flexible and Context-Sensitive?

Abstract: The claim that the human cognitive system tends to allocate resources to the processing of available inputs according to their expected relevance is at the basis of relevance theory (where it constitutes the first, cognitive principle of relevance). The main thesis of this chapter is that this allocation can be achieved without computing expected relevance. When an input meets the input condition of a given modular procedure, it gives this procedure some initial level of activation. Input-activated procedures are in competition for the energy resources that would allow them to follow their full course. What determines which of the procedures in competition get sufficient resources to trigger their full operation is the dynamics of their activation. This dynamics depend both on the prior degree of mobilisation of a modular procedure and on the activation that propagates from other active modules. It is quite conceivable also that the mobilisation of some procedures has inhibitory effects on some others. The relevance-theoretic claim is that, at every instant, this dynamics of activation provides rough physiological indicators of expected relevance. The flow of energy in the system is locally regulated by these indicators. As a result, those input-procedure combinations that have the greatest expected relevance are the more likely ones to receive sufficient energy to follow their course.

Modular and Expandable Irrigation Controller

Abstract: Described herein are several embodiments relating to modular irrigation controllers. In many implementations, the irrigation controllers are modular in that various functional components of the irrigation controller are implemented in removable modules that when inserted into position within the controller, expand the capabilities of the controller. Also described are various different types of expansion modules that may be coupled to the modular controller, having as variety of functions and features, as well as related methods of use and configuration of these modules in the controller. In one implementation, an expansion module is provided that includes a microcontroller capable of sending and receiving data communications to and from a main microcontroller of the controller that executed irrigation programs, the data communications relating to an irrigation program.

Independently Extensible Solutions to the Expression Problem

Abstract: The expression problem is fundamental for the development of extensible software. Many (partial) solutions to this problem have been proposed in the past, but the question of how to use different, independent extensions jointly has received less attention so far. This paper proposes solutions to the expression problem that make it possible to combine independent extensions in a flexible, modular, and typesafe way. The solutions, formulated in the programming language Scala, are affected with only a small implementation overhead and are relatively easy to implement by hand.

Singlets, cascaded singlets, and the nonresonating node model for advanced modular design of elliptic filters

Abstract: The singlet, which contains one resonator and generates one transmission zero, is introduced as the most basic building block for modular design of elliptic filters. Higher-order elliptic filters are designed by cascading singlets to generate the required transmission zeros. A novel model, the nonresonating node model (NRNM), which contains both resonating and nonresonating nodes is then introduced. The model allows a high level of modularity in the design of elliptic filters. Example filters are designed and measured to validate the model and the design approach.

Modular domain structure: a biomimetic strategy for advanced polymeric materials.

Abstract: A long lasting challenge in polymer science is to design polymers that combine desired mechanical properties such as tensile strength, fracture toughness, and elasticity into one structure. A novel biomimetic modular polymer design is reported here to address this challenge. Following the molecular mechanism used in nature, modular polymers containing multiple loops were constructed by using precise and strong hydrogen bonding units. Single-molecule force-extension experiments revealed the sequential unfolding of loops as a chain is stretched. The excellent correlation between the single-molecule and the bulk properties successfully demonstrates our biomimetic concept of using modular domain structure to achieve advanced polymer properties.

Adaptive robust force control for vehicle active suspensions.

Abstract: SUMMARY In this paper, the modular adaptive robust control (MARC) technique is applied to design the force loop controller of an electro-hydraulic active suspension system. A key advantage of this modular design approach lies in the fact that the adaptation algorithm can be designed for explicit estimation convergence. The effect of parameter adaptation on force tracking performance can be compensated and thus it is possible to guaranteed certain control performance. Experimental results from a quarter-car active suspension test rig show that when realistic external disturbances and measurement noises exist, the modular design achieves a better estimate than the non-modular ARC design. The improved estimation was found to result in control signals with slightly lower magnitude while maintaining similar tracking performance. Copyright # 2004 John Wiley & Sons, Ltd.

Real-time LUT-based network topologies for dynamic and partial FPGA self-reconfiguration

Abstract: Xilinx Virtex FPGAs offer the possibility of dynamic and partial run-time reconfiguration. If a system uses this feature the designer has to take care, that no signal lines cross the border to other reconfigurable regions. Traditional solutions connecting modules on a dynamic and partial reconfigurable system use TBUF elements for connection and separation of the functional blocks. While automatically placing and routing the design, the routing-tool sometimes uses signal lines which cross the module border. The constraints given by the designer are ignored. To solve this problem, we use slices instead of TBUF elements which leads to a benefit by using an automatic modular design flow. This paper gives an overview of the used techniques and the complete system on a Xilinx XC2V3000 FPGA.

Z-Tiles: building blocks for modular, pressure-sensing floorspaces

Abstract: A new interactive floorspace has been developed which uses modular odes connected together to create a pressure-sensitive area of varying size and shape, giving it the potential to be integrated into an interactive environment. The floorspace uses an array of force-sensitive resistors on each node to detect pressure, and that pressure information is output by way of a self-organised network formed by the floor nodes. This paper describes the pressure sensing and network systems, suggests potential applications of the floorspace, and introduces the further research on in-network data aggregation being carried out using the system's framework.

Rethinking the supply chain: an automotive perspective

Abstract: This paper contends that the description of tiering within automotive supply chains is likely to require redefining in light of the development of modular supply and that a natural consequence of modular supply will be the transfer of value‐adding activity throughout the supply chain. Two concepts are presented to illustrate the characteristics that are likely to be required for suppliers to succeed within a modular environment. These concepts are applied to a supply chain currently in the process of accommodating modular supply. The findings suggest that whilst modularity accrues a number of tangible benefits to both the original equipment manufacturer (OEM) buyer and the modular supplier, the skills required to become a modular supplier are likely to result in a number of first‐tier suppliers either exiting the industry or becoming second or third‐tier suppliers.

PROFINET - scalable factory communication for all applications

Abstract: PROFINET is the industrial Ethernet standard devised by PROFIBUS International (PI) for either modular machine and plant engineering or distributed IO. Using a plant-wide multi-vendor engineering for modular machines, commissioning time as well as costs are reduced. With distributed IO IO-controllers (e.g., PLCs) with their associated IO-devices may also be integrated into PROFINET solutions. Communication is a major part of PROFINET. Real-time communication for standard factory automation applications as well as extensions which enables motion control applications is covered in a common real-time protocol. The advantages of modular and multi-vendor engineering and distributed IO can be used even in applications with time-critical data transfer requirements.

Decentralized Pricing and Capacity Decisions in a Multitier System with Modular Assembly

Abstract: We model a modular assembly system in which a final assembler outsources some of the assembly task to first-tier suppliers (subassemblers), who produce modules made up of multiple components. The assembler sets module prices it will pay to the subassemblers, the subassemblers set component prices they will pay to suppliers, and then all players choose how much capacity to install, with the minimum capacity choice determining system capacity. Finally, stochastic end-product demand is observed and all players produce (and are paid for) the same number of units-the minimum of demand and system capacity. We characterize equilibrium price and capacity choices, and then use that characterization to derive results regarding higher-level structural choices by the assembler-such as how to group components into modules and which suppliers to choose as subassemblers. We also compare performance of the system to a traditional assembly system with an assembler and suppliers but without subassemblers.

GATE : a simulation toolkit for PET and SPECT

Abstract: Monte Carlo simulation is an essential tool in emission tomography that can assist in the design of new medical imaging devices, the optimization of acquisition protocols, and the development or assessment of image reconstruction algorithms and correction techniques. GATE, the Geant4 Application for Tomographic Emission, encapsulates the Geant4 libraries to achieve a modular, versatile, scripted simulation toolkit adapted to the field of nuclear medicine. In particular, GATE allows the description of time-dependent phenomena such as source or detector movement, and source decay kinetics. This feature makes it possible to simulate time curves under realistic acquisition conditions and to test dynamic reconstruction algorithms. A public release of GATE licensed under the GNU Lesser General Public License can be downloaded at the address this http URL

Pegasys: software for executing and integrating analyses of biological sequences.

Abstract: We present Pegasys – a flexible, modular and customizable software system that facilitates the execution and data integration from heterogeneous biological sequence analysis tools.

Scalable and modular algorithms for floating-point matrix multiplication on FPGAs

Abstract: Summary form only given. The abundant hardware resources on current FPGAs provide new opportunities to improve the performance of hardware implementations of scientific computations. We propose two FPGA-based algorithms for floating-point matrix multiplication, a fundamental kernel in a number of scientific applications. We analyze the design tradeoffs in implementing this kernel on FPGAs. Our algorithms employ a linear array architecture with a small control logic. This architecture effectively utilizes the hardware resources on the entire FPGA and reduces the routing complexity. The processing elements (PEs) used in our algorithms are modular so that floating-point units can be easily embedded into them. In our designs, the floating-point units are optimized to maximize the number of PEs integrated on the FPGA as well as the clock speed. Experimental results show that our algorithms achieve high clock speeds and provide good scalability. Our algorithms achieve superior sustained floating-point performance compared with existing FPGA-based implementations and state-of-the-art processors.

Performance-derived behavior vocabularies: data-driven acquisition of skills from motion

Abstract: Control for and interaction with humanoid robots is often restrictive due to limitations of the robot platform and the high dimensionality of controlling systems with many degrees of freedom. We focus on the problem of providing a "skill-level interface" for a humanoid robot. Such an interface serves as (i) a modular foundation for structuring task-oriented control, (ii) a parsimonious abstraction of motor-level control (e.g. PD-servo control), and (iii) a means for grounding interactions between humans and robots through common skill vocabularies. Our approach to constructing skill-level interfaces is two-fold. First, we propose a representation for a skill-level interface as a "behavior vocabulary," a repertoire of modular exemplar-based memory models expressing kinematic motion. A module in such a vocabulary encodes a flow field (or gradient field) in joint angle space that describes the "flow" of kinematic motion for a particular skill-level behavior, enabling prediction from a given kinematic configuration. Second, we propose a data-driven method for deriving behavior vocabularies from time-series data of human motion using spatio-temporal dimension reduction and clustering. Results from evaluating an implementation of our methodology are presented along with the application of derived behavior vocabularies as predictors towards on-line humanoid trajectory formation and off-line motion synthesis.

Quantifying modularity in the evolution of biomolecular systems.

Abstract: Functional modules are considered the primary building blocks of biomolecular systems. Here we study to what extent functional modules behave cohesively across genomes:That is, are functional modules also evolutionary modules? We probe this question by analyzing for a large collection of functional modules the phyletic patterns of their genes across 110 genomes. The majority of functional modules display limited evolutionary modularity. This result confirms certain comparative genome analyses, but is in contrast to implicit assumptions in the systems analysis of functional genomics data. We show that this apparent interspecies flexibility in the organization of functional modules depends more on functional differentiation within orthologous groups of genes, than on noise in the functional module definitions. When filtering out these sources of nonmodularity, even though very few functional modules behave perfectly modular in evolution, about half behave at least significantly more modular than a random set of genes. There are substantial differences in the evolutionary modularity between individual functional modules as well as between collections of functional modules, partly corresponding to conceptual differences in the functional module definition, which make comparisons between functional module collections biologically difficult to interpret. Analysis within one collection does not suffer from such differences, and we show that within the EcoCyc metabolic pathway database, biosynthetic pathways are evolutionarily more modular than catabolic pathways.

Adaptive tracking and regulation of a wheeled mobile robot with controller/update law modularity

Abstract: A new adaptive controller is developed for wheeled mobile robots with parametric uncertainty in the dynamic model. The main theoretical contribution is the modular manner in which the control law and parameter update law are designed. This feature allows for design flexibility in the selection of the update law, and can be exploited to improve the transient response of the adaptive controller. The proposed controller also has the important feature of being applicable to both the tracking and regulation problems. The modularity of the adaptive controller is experimentally demonstrated on a K2A Cybermotion mobile robot that has been modified to allow for the implementation of torque-level control inputs. In particular, the adaptive controller with a gradient update law is evaluated vis-a/spl grave/-vis a least-squares update law.