Applying biological principles to designs of network services

This paper describes application of key biological principles and mechanisms to the design of network services. In biological systems, an individual entity (e.g., a bee in a bee colony) follows a simple set of behavior policies (e.g., migration, replication, death), yet a group of entities (e.g., a bee colony) exhibits complex emergent behavior with useful properties such as scalability and adaptability. Analogous to the biological systems, in the biologically inspired networking architecture that we present in this paper, a group of autonomous agents that implement simple behavior policies collectively provide a network service. We believe if a network service is modeled after biological principles and mechanisms, the network service is able to meet key requirements such as scalability, adaptability, survivability, simplicity and autonomy. This paper discusses key biological principles that can be applied to the design of network services, and demonstrates through simulations how network services built based on biological principles evolve to improve service performance.     

A simple terminal multiplexer for a Cambridge Ring

This paper describes the design and operation of software written for the SEEL Ltd 3012 Cambridge Ring Terminal Concentrator. The combination allows network-transparent bytewise communication between any two asynchronous ports on a single or multi-terminal concentrator system. A facility is provided to identify ports with either terminals or computers and thus to allow logged-in sessions between a particular terminal and any of the computers attached to the system in a way that exactly emulates a direct hardwired connection. An alternative to this user-instigated connection is also provided, so that peripherals such as serial lineprinters and plotters can be accessed in a shared fashion from spooled queues on some or all of the computers in the system. The current system consists of three hardware units handling the data traffic between eighteen visual display terminals and a PDP-11, a GEC and a four VAX computers. A shared serial lineprinter is also provided on this system.     

Realistic Brownian Dynamics simulations of biological molecule separation in nanofluidic devices

We present a Brownian Dynamics model of biological molecule separation in periodic nanofilter arrays. The biological molecules are modeled using the Worm-Like-Chain model with Hydrodynamic Interactions. We focus on short dsDNA molecules; this places the separation process either in the Ogston sieving regime or the transition region between Ogston sieving and entropic trapping. Our simulation results are validated using the experimental results of Fu et al. (Phys Rev Lett 97:018103, 2006); particular attention is paid to the model’s ability to quantitatively capture experimental results using realistic values of all physical parameters. Our simulation results showed that molecule mobility is sensitive to the device geometry. Moreover, our model is used for validating the theoretical prediction of Li et al. (Anal Bioanal Chem 394:427–435, 2009) who proposed a separation process featuring an asymmetric device and an electric field of alternating polarity. Good agreement is found between our simulation results and the predictions of the theoretical model of Li et al.     

A novel printhead multiplexer data registration chip system with injection cavity design

Microsystem Technologies - The integration of logic function is enabling TIJ-based products to move ever further up-market. The depicted integrated circuit TIJ transducer array serves 1024 jets and...     

A framework for distributing object-oriented designs

In response to the increasing demand of information processing, the object-oriented and client-server paradigms are becoming more pervasive. While implementation solutions integrating these two paradigms are widespread, there is minimal evidence that the merging of these two concepts has been considered at the design level. Specifically, object-oriented designs remain sequential in essence, and their mapping to a given distributed object-oriented programming language is left to the creativity and/or expertise of software engineers. In this paper, we propose a quantitative approach and a supporting tool to assist the designer in the distribution process. The metrics presented provide an easy way, but still consistent and reliable, to gauge the distribution suitability of various object-oriented design entities. Published online: 29 August 2002     

A digital dilution chip using inter-well valves controlled by a ternary microfluidic multiplexer

We present a digital dilution chip of 2 × 6 well array that is capable of changing the dilution ratio. We mixed the diluted samples with other samples by using inter-well valves. The previous continuous and digital dilution chips diluted samples that had a fixed dilution ratio depended on the structure of the branched microchannel or the volume of the well. The present chip can perform the programmable mixing process that selectively fills, merges, and splits the identical wells by controlling the inter-well valves. Thus, the present digital dilution chip can easily change the dilution ratio without any structural change. In this study, the present chip changed the dilution ratio, such as the linear or exponential ratio, within a 4.2% dilution difference. They were then mixed with other samples within a 3.4% mixing difference. In order to reduce the number of interconnection ports that transferred the pressure to inter-well valves, we also applied a latched ternary multiplexer and reduced nine interconnection ports of inter-well valves to five. By diluting the sample with different dilution ratios based on the well array, the present chip can be easier for users and more suitable to high-throughput screen systems.     

A comparative study of two shovel designs

In the present study a modified shovel design with two perpendicular shafts is presented. This modified, two-shaft shovel was compared with a regular shovel. The modified shovel was evaluated and tested in a controlled laboratory environment using surface electromyography recorded from the lumbar paraspinal muscles. The new shovel design was also tested in a field study using ratings of perceived exertion. The results indicate that there was a significant reduction in EMG values of the lumbar paraspinal muscles and a consistent reduction in perceived exertion ratings while the modified shovel was being used for removing dirt in digging trenches up to 90 cm in depth.     

Optimization, block designs and No Free Lunch theorems

We study the precise conditions under which all optimization strategies for a given family of finite functions yield the same expected maximization performance, when averaged over a uniform distribution of the functions. In the case of bounded-length searches in a family of Boolean functions, we provide tight connections between such “No Free Lunch” conditions and the structure of t-designs and t-wise balanced designs for arbitrary values t. As a corollary, we obtain a nontrivial family of n-variate Boolean functions that satisfies the “No Free Lunch” condition with respect to searches of length Ω(n1/2/log1/2n). Modifying the construction, we also obtain nontrivial “No Free Lunch” families of functions with large ranges.     

A structural neural system for mechanical, biological, and environmental systems

A structural neural system (SNS) and continuous sensors that mimic the neurons of the human biological system are described for monitoring the health of large structures. An example of use of the SNS to monitor damage on a nine meter long wind turbine blade is also described. The blade is a complex anisotropic structure that was tested at the National Renewable Energy Laboratory, Golden, Colorado, USA under quasi static loading to determine the strength and ability of the blade to withstand wind loading. The SNS along with piezoelectric sensors was installed to monitor the composite blade material during this testing. Multiple cracks originated during this test and were detected by the SNS well before the final failure of the blade. This testing provides confidence that SNS has the capability to monitor crack growth in complex anisotropic structures using piezoelectric sensors. The SNS is currently being extended to sense signals from other types of sensors including continuous sensors based on accelerometers, pressure sensors, piezoresistive, chemical, and biosensors. This would extend application of the SNS into biological and environmental systems where different types of sensors are used to measure chemicals and biological materials. It is predicted that the SNS can provide high accuracy, low cost, and simplicity for monitoring the health of many types of systems.     

A Method for Minimization Design of Two-Level Logic Networks Using Multiplexer Universal Logic Modules

A decomposition approach of the combinational functions is discussed.A design method,by which the minimization or near minimization of two-level combinational network can be obtained,is presented for a combinational function realized by using multiplexer universal logic modules.Using the method,the automated synthesis of the combinational functions can be accomplished on a computer.     

四路串行CMOS复接器的设计实现

通信系统中,数字复接是提高带宽利用率的一项重要技术,将多路并行低速信号转变为高比特率的串行数字流。首先使用Cadence软件仿真基本门级CMOS电路,通过自下而上的FPGA设计方法和Verilog硬件描述语言,设计四路串行复接器的功能组成模块,完成QuartusⅡ平台上的可综合验证。最后提出了复接器CMOS集成电路的设计思路。     

A : A tool for identifying and repairing un-machinable shapes in designs

Providing early feedback on the manufacturability of a part design can greatly improve the quality of the product while reducing the time and cost of production. However, the necessary manufacturing knowledge is not always available. Computer tools that can provide this manufacturing knowledge by analyzing a design suggesting changes to improve its manufacturability would be a valuable asset to a designer. To this end, we present an approach to automatically generate redesign suggestions to improve the manufacturability of machined parts. Novel aspects of this approach include the ability to identify un-machinable shapes in a part and transform them into machinable features and to automatically identify the possible shape transformations based on properties of the machining equipment. This increases the scope of redesign generation tools by allowing them to be applied to parts that are not already machinable. We have developed a system called automated redesign for machined parts ( ) that assists users in repairing parts that contain un-machinable shapes.     

A categorical outlook on relational modalities and simulations

We characterise bicategories of spans, relations and partial maps universally in terms of factorisations involving maps. We apply this characterisation to show that the standard modalities □ and ? arise canonically as extensions of a predicate logic from functions to (abstract) relations. When relations and partial maps are representable, we exhibit logical predicates for the power-object and partial-map-classifier monads. We also show that the □ modality gives the relevant pullbacks of subobjects in the internal logic of categories of partial maps. Organising modal formulae fibrationally, we exhibit an intrinsic relationship between their satisfaction relative to transition systems and the notion of simulation. In this setting, we use the biclosed structure of the bicategory of relations to give a new proof of the standard fact that observational similarity implies similarity.     

Large-scale simulations of self-organizing neural networks on parallel computers: application to biological modelling

In this contribution we report about a study of a very versatile neural network algorithm known as “Self-organizing Feature Maps” and based on earlier work of Kohonen [1,2]. In its original version, the algorithm addresses a fundamental issue of brain organization, namely how topographically ordered maps of sensory information can be formed by learning.

This algorithm is investigated for a large number of neurons (up to 16 K) and for an input space of dimension d900. To meet the computational demands this algorithm was implemented on two parallel machines, on a self-built Transputer systolic ring and on a Connection Machine CM-2.

We will present below

1. (i) a simulation based on the feature map algorithm modelling part of the synaptic organization in the “hand-region” of the somatosensory cortex,

2. (ii) a study of the influence of the dimension of the input-space on the learning process,

3. (iii) a simulation of the extended algorithm, which explicitly includes lateral interactions, and

4. (iv) a comparison of the transputer-based “coarse-grained” implementation of the model, and the “fine-grained” implementation of the same system on the Connection Machine.