A chip scale nanofluidic pump using electrically controllable hydrophobicity

The traditional microfluidic systems and devices faced limitations such as power consumption and high driving force in the attempt for implementation as chemical analysis and environmental monitoring systems. The up-to-date development of chemistry and biology has generated great demand for lab-on-a-chip performing specific chemical and biological analysis, clinical diagnostics and biomedical processing. Manipulation of ultrasmall amount and great varieties of biofluids has also been a major issue challenging many researchers. Here we demonstrate in this article, a device utilizing electrically controllable surface tension as the driving force to deliver fluid flow in the order of nanoliters per minute or even smaller, without a dedicated actuator. This device is capable of pumping a continuous liquid column. This actuation mechanism of fluid flow in this device is based on electrowetting-on-dielectric (EWOD) effect and the physics of the fluid dynamics is governed by Navier–Stokes equation. It also has a built-in metering feature to precisely determine the flow rate without an additional flow sensor. The experimental results show that water can be electrically actuated successfully to flow in the microchannel at a flow rate of 18 nl/min under a potential of as low as 20 V. This is very attractive for applications which require an ultra miniaturized metering pump operated at a low power for portable environmental monitoring instruments, chemical analysis systems, implantable medical devices, drug delivery systems and clinical diagnostic systems.     

A distributed optical fiber sensor for temperature detection in power cables

The power transfer capacity of an underground power cable is limited by high-temperature regions that occur along the cable. It is very difficult to determine and control these ‘hot spots’. Optimum use and temperature profile control of power cables before and during load transmission can be achieved with real-time processing of temperature data. There are various methods developed for this purpose such as conventional point temperature measurement method, where a large number of sensors and connectors are required, and methods based on mathematical models which can only approach real values by approximation.In this study, temperature detection in an XLPE insulated 154 kV power cable is performed using a distributed sensing method where the optical fiber itself behaves as a sensor. Therefore, there is no need for the devices of conventional method. Moreover, contrary to methods based on mathematical models, where it is difficult to predict environmental variations, this method considers the variations with a temperature resolution of ±1 °C. Distributed temperature sensing (DTS) method, detection system configuration and required system parameters are explained in the paper. Experimental results obtained for 126 and 412 m cables show a temperature resolution of ±1 °C and a spatial resolution of 1.22 m. Simulations for a 10 km cable are also given. Results show that DTS is a reliable method for both short and long range cable systems.     

Application-specific architectures for energy-efficient database query processing and optimization

Data processing on a continuously growing volume of data and the increasing power restrictions have become an ubiquitous challenge in our world today. Besides parallel computing, a promising approach to improve the energy efficiency of current systems is to integrate specialized hardware. This paper presents two application-specific architectures to accelerate basic database operators frequently used in modern database systems: an extended instruction set based on a given Cadence Tensilica processor (ASIP) and a comparable application-specific integrated circuit (ASIC). The ASIP is implemented in a system-on-chip and manufactured in a 28 nm CMOS technology to realize measurements of performance and power consumption. Furthermore, the comparison with the ASIC blocks allows to quantify the results with the ASIP approach in terms of throughput, area, and energy efficiency as well as to discuss the capabilities and limitations when accelerating selected database operators.     

Software–hardware method of serial interface controller implementation

A software-hardware method of serial interface controller implementation is proposed which includes separate processing of data link and physical layer functions The data link layer functions are implemented in software using a microcontroller (MC), and physical level functions -in hardware using programmable logical device (PLD). The proposed method provides optimal ratio of hardware and software costs for interface controller (IC) implementation, and effective utilization of MC computing power. Based on this method a structure of the universal serial interface controller is proposed.     

Software–hardware method of serial interface controller implementation

A software-hardware method of serial interface controller implementation is proposed which includes separate processing of data link and physical layer functions The data link layer functions are implemented in software using a microcontroller (MC), and physical level functions -in hardware using programmable logical device (PLD). The proposed method provides optimal ratio of hardware and software costs for interface controller (IC) implementation, and effective utilization of MC computing power. Based on this method a structure of the universal serial interface controller is proposed.     

A compact implantable RFID tag antenna dedicated to wireless health care

Implantable tag antennas are an integral component of contemporary pervasive patient monitoring setups envisioned to reduce the medical errors and improve the quality of health care facilities. These tags, embedded into the human body, transmit critical patient information to the external equipment via a wireless communication link. This research article presents an implantable compact folded dipole antenna of size 10 mm × 15 mm × 2 mm, designed to operate in the industrial‐scientific‐medical band (2.4‐2.48GHz). A three‐layered phantom representing the human arm is used to evaluate the subcutaneous antenna performance. The tag antenna embedded in the middle of the fat layer offers a maximum gain of ?16.3 dBi. The tag antenna performance as a function of implant position and phantom dimensions is analyzed. Link budget calculations show that with the achieved antenna gain the link power exceeds the required power by 38.37 dBm, and hence wireless communication is viable.     

应用RFID技术实现医用植入装置的通信

典型的医用植入装置由体外部分和植入体两部分组成,二者之间通过射频载波传输能量和信息,这与广泛应用的射频识别技术非常相似。本文分析研究了它们在技术和应用层面的特点,提出了一种基于商用RFID技术及其器件实现的医用植入装置双向通信的设计,对于具体实现过程中的关键技术、必要的技术裁剪和技术扩展进行了较为详细的介绍。     

Extensible block-level storage virtualization in cluster-based systems

High-performance storage systems are evolving towards decentralized commodity clusters that can scale in capacity, processing power, and network throughput. Building such systems requires: (a) Sharing physical resources among applications; (b) Sharing data among applications; (c) Allowing customized data views. Current solutions typically satisfy the first two requirements through a cluster file-system, resulting in monolithic, hard-to-manage systems. In this paper we present a storage system that addresses all three requirements by extending the block layer below the file-system. First, we discuss how our system provides customized (virtualized) storage views within a single node. Then, we discuss how it scales in clustered setups. To achieve efficient resource and data sharing we support block-level allocation and locking as in-band mechanisms. We implement a prototype under Linux and use it to build a shared cluster file-system. Our evaluation in a 24-node cluster setup concludes that our approach offers flexibility, scalability and reduced effort to implement new functionality.     

Gastric-fluid-utilizing micro battery for micro medical devices

A variety of micro medical devices have been developed to provide more advanced and less invasive medical treatment. An effective power supply is crucial to the operation of these devices. Currently, two types of power supply are used: small batteries or radio-power transmission. However, the former limits the operating time of the devices, while radio-power transmission affects other medical devices due to the electromagnetic waves. In this paper, we report on a gastric-fluid-utilizing micro battery (GMB) that utilizes the gastric fluid in the stomach as an electrolyte. The GMB is designed to be used in the stomach and to generate electricity based on the principle of the voltaic cell. It consists only of biocompatible materials, including the electrodes, porous ceramic filter, and polydimethylsiloxane casing. Platinum deposited on a thin glass plate and a zinc plate work as positive and negative electrodes, respectively. Though zinc dissolves during the generation of electricity, it is an essential trace metal for humans and, given the small amount released, is not toxic. The porous ceramic filter placed between the electrodes filters out any foreign materials in the stomach fluid and holds the gastric fluid by capillary attraction. In experiments, GMB successfully generated 1.0 mW (0.42 V, 2.41 mA) with a 200-Ω external load. It generated a stable output voltage of 0.6 V for more than 39 min with a 5-kΩ external load. We demonstrated the feasibility of the GMB for medical applications by successfully supplying power to a telemetric system and a tiny DC motor that is commercially available.     

Double permanent magnet vibration power generator for smart hip prosthesis

Ever since the first studies about biomedical implantable devices, the problem of how to energize them has stood out as both important and notoriously difficult to solve. In order to extend the lifetime of implants, it is imperative to develop power generators that are autonomous, safe and maintenance-free. Energy harvesting is a natural way of meeting these requirements. First, the energy source is theoretically everlasting, a fact that helps to guarantee the autonomy. Second, the energy is obtained from the environment of the application itself, contributing to its safety. Finally, a properly designed energy harvesting system is very unlikely to ever require maintenance. This paper follows this line and describes an electromagnetic power transducer that harvests electrical energy from the human gait and stores it. An efficient power management module uses the stored energy to energize the telemetric system of a smart hip prosthesis implant, enabling the early detection of loosening, the target application of this work. The system is able to extract a total 1912.5 μJ of usable energy under normal walking conditions.     

A bi-directional rotating fluid bearing system

 Most fluid bearing systems with grooves on the journal/thrust bearing surfaces were designed to rotate in a specified direction and cannot be reversed. This feature of such fluid bearings limits their application range and hence, a bi-directional rotating fluid bearing system is proposed. The results of numerical simulation on the dynamic characteristics of such bearing system are presented and compared with those of one-directional rotating fluid-bearing system. It shows that for the same load capacity and stiffness requirement, the bi-directional rotating fluid bearing system has a higher power consumption than that of the one-directional counterpart. However, the bi- directional rotating fluid bearing system provides the freedom of rotating spindle motor in either direction and widens the application range of fluid bearing spindle motors. Received: 5 July 2001/Accepted: 17 October 2001     

Xen2MX: High-performance communication in virtualized environments

Cloud computing infrastructures provide vast processing power and host a diverse set of computing workloads, ranging from service-oriented deployments to high-performance computing (HPC) applications. As HPC applications scale to a large number of VMs, providing near-native network I/O performance to each peer VM is an important challenge. In this paper we present Xen2MX, a paravirtual interconnection framework over generic Ethernet, binary compatible with Myrinet/MX and wire compatible with MXoE. Xen2MX combines the zero-copy characteristics of Open-MX with Xen's memory sharing techniques. Experimental evaluation of our prototype implementation shows that Xen2MX is able to achieve nearly the same raw performance as Open-MX running in a non-virtualized environment. On the latency front, Xen2MX performs as close as 96% to the case where virtualization layers are not present. Regarding throughput, Xen2MX saturates a 10 Gbps link, achieving 1159 MB/s, compared to 1192 MB/s of the non-virtualized case. Scales efficiently with the number of VMs, saturating the link for even smaller messages when 40 single-core VMs put pressure on the network adapters.     

FPGA-based architecture for hardware compression/decompression of wide format images

In this article, we present a popular lossless compression/decompression algorithm, GZIP, and the study to implement it on an FPGA-based architecture, the ADM-XRC board from ALPHA DATA parallel system ltd. The algorithm is lossless, and applied to “bi-level” images of large size (A0 format). It ensures a minimum compression rate for the images we are considering. It aims to decrease storage requirements and transfer times, which are critical for wide format printing systems. In a wide format document industry, raster data are most of time processed in an uncompressed format, in order to apply processing (P) before printing (p). An example of a copy chain is composed of scanner, set of processing operations, storage, link and printer. We propose to use a compressed format as the new data-flow representation to improve the performances of the printing system. For example, the compression (C) is applied as soon as the data are produced by the scanner, and decompression (D) is performed at the last stage, before printing. The set of processing is applied to compressed images. The proposed architecture for the compressor is based on a hash table and the decompressor is based on a parallel decoder of the Huffman codes. We implemented the proposed architecture for compression and decompression algorithms on FPGA Xilinx Virtex XCV 400.     

MPSoC based on Transport Triggered Architecture for baseband processing of an LTE receiver

Wireless communication over LTE (long term evolution) brings several design challenges to industry and academia, due to its high throughput demand. Specially in the case of hand held mobile devices where the power budget is very limited and high throughput requires more computation power. On the other hand, the industry is struggling for flexible hardware solution, a Software Defined Radio (SDR), to amortize huge costs of hardware changes to suit the continued evolution in wireless standards. In this article, an MPSoC design has been presented for the baseband processing of a 20 MHz LTE system. Transport Triggered Architecture (TTA) has been preferred over conventional DSPs/VLIW architectures as processing element (PE) of MPSoC. Processing tasks are statically scheduled. Synchronization among the PEs is based on polling of a shared memory space. In addition an approach is presented to organize I/O buffer in such a way that the stalling probability of a PE should be reduced to exploit efficiently data and task level parallelism. The total power consumption by all the PEs synthesized on 130 nm technology at 200 MHz and 1.5 V is 105.04 mW. The total energy consumption to process one subframe including carrier recovery is 0.0767 mJ. Our study shows that TTA architecture brings several improvements in conventional SIMD/VLIW architectures. TTA as contrary to other run time designs has a guaranteed performance and lower energy consumption due to the fact that all the data dependency/independency issues are resolved at compile time. Further, it is also true due to the fact that TTA has a reduced register file (RF) traffic, number of RF ports and lower overall cycle count for a given task. To the best of author’s knowledge this article is among the first few published articles on LTE receiver implementation with published figures like time, frequency, power and perhaps the first article explaining further in detail about data access pattern to process an LTE subframe, memory organization, subsystem interconnection, and synchronization.     

Efficient path protection in bi-directional WDM systems

Bi-directional WDM transmission is a technique that allows data to be transmitted simultaneously in both directions of a fiber, with different sets of wavelength channels for each direction. Compared with unidirectional WDM systems, it not only saves the cost of deploying extra fibers, but also allows more flexible bandwidth provisioning. To exploit this flexibility, we investigate path protection schemes for bi-directional WDM transmission systems in this paper. With path protection, a call is accepted if and only if an active data path together with a disjointed backup path can be found in the network. With bi-directional WDM, backup resource sharing in both directions of a fiber is possible. Based on a set of judiciously designed link cost functions, two original path protection schemes are proposed in this paper, BiPro and BiProLP. BiProLP aims at further economizing the hardware cost incurred by BiPro. In contrast to the traditional unidirectional schemes, we show that both BiPro and BiProLP can yield noticeably lower call blocking probability, higher system capacity and shorter active/backup path length.     

A novel augmented reality for hidden organs visualisation in surgery: enhanced super-pixel with sub sampling and variance adaptive algorithm

In recent years, Augmented Reality (AR) has gained more attention as an effective tool in medical surgeries. The potentials of using AR in the medical field can change conventional medical procedures. However, the technology still facing fundamental challenges, especially hidden organs, for example, the organs behind the bowel and liver. The surgeries in these areas lack accuracy in the visualization of the soft tissues behind the bowel and liver like the uterus and gall bladder. This research aims to improve the accuracy of visualisation and the processing time of the augmented video. The proposed system consists of an enhanced super-pixel algorithm with variance weight adaptation and subsampling method. The simulation studies show significant improvements in visualization accuracy and a reduction in processing time. The results show reduced visualisation error by 0.23 mm. It provides better accuracy of the video in terms of visualization error from 1.58?~?1.83 mm to 1.35?~?1.60 mm, and the processing time decreases from 50?~?58 ms/frames to 40?~?48 ms/frames. The proposed system \ focused on the pixel refinement for the 3d reconstruction of the soft tissue, which helps solve the issue of visualising the bowel and liver in an augmented video.

     

Hybrid wireless sensor network for building energy management systems based on the 2.4 GHz and 400 MHz bands

In this paper, a hybrid wireless sensor network (WSN) system is considered and implemented for the building energy management systems. Characteristics of the radios, which are based on the 2.4 GHz and 400 MHz bands, respectively, are analyzed for the building environments. For battery-operated portable sensors, narrow-bandwidth radios of the 400 MHz band are employed in a star connection between their parent nodes. Between the parent nodes, a mesh network is constructed for an efficient and fast data transmission based on the wide-bandwidth radios of the 2.4 GHz band. The hybrid WSN system is implemented and tested for a building environment and provides a reliable wireless communication link for gathering sensing data.     

Estimation of volume change rates of Greenland's ice sheet from ICESat data using overlapping footprints

Data from the ICESat/GLAS laser altimetry mission is used to obtain an estimate of the volume change of Greenland's ice sheet over the time span of February 2003 to April 2007. A novel processing strategy is developed and applied. It uses approximately 1 million ICESat elevation differences at geometrically overlapping footprints of both crossing and repeated tracks. The data are edited using quality flags defined by the ICESat/GLAS science team, as well as other additional criteria. In order to reduce the influence of surface slope, we propose a correction based on the ICESat/GLAS laser altimetry digital elevation model. Three slightly different processing strategies to convert the observed temporal elevation differences to elevation/volume changes are compared for 6 different drainage systems, further divided into regions above and below 2000 m in elevation. The final chosen strategy includes the correction for surface slopes, but does not include the removal of outlying elevation changes. For the region above 2000 m, a positive elevation change rate of 2 cm/year is obtained, which corresponds to a volume change rate of 21 km³/year. For the region below 2000 m the estimated elevation change rate is ? 24 cm/year, which corresponds to a volume loss of 168 km³/year. In general, the obtained results are in agreement with trends discovered by other authors that were also derived from laser altimetry. Nevertheless, the estimation obtained in this study suggests a more negative trend than those obtained previously. The differences can be explained by differences in the sampling of the region below 2000 m and, to a certain extent, by different time spans of the datasets used. A representative sampling of coastal areas is identified as the most critical issue for an accurate estimation of volume change rates in Greenland.     

Representation of the computer-aided design process by a network of decision tables

Large-scale implementation of computer-aided design of structural systems, as opposed to the analysis or mathematical optimization of such systems, had been largely unsuccessful to date, owing largely to the difficulty of representing the myriad decisions and processing steps involved.It is shown that decision tables are an ideal tool for representing the detailed decisions and processing steps. The interaction between the data items and the transformations including decision tables is concisely represented by networks of ingredience and dependence. Finally, the iterative, open-ended nature of the design process is accommodated by assigning to each data item a status indicator, which specifies whether the item is valid or void. It is shown that only two basic recursive routines are needed to link the data together, either to evaluate a given item by evaluating all of its ingredients or to make all dependents of a modified data item void.Examples illustrating the application of the representation are included, using the 1969 AISC Specifications as a basis.     

A robust framework for real-time distributed processing of satellite data

It is estimated that future satellite instruments such as the Advanced Baseline Imager (ABI) and the Hyperspectral Environmental Suite (HES) on the GOES-R series of satellites will provide raw data volume of about 1.5 Terabyte per day. Due to the high data rate, satellite ground data processing will require considerable computing power to process data in real-time. Cluster technologies employing a multi-processor system present the only current economically viable option. To sustain high levels of system reliability and operability in a cluster-oriented operational environment, a fault-tolerant data processing framework is proposed to provide a platform for encapsulating science algorithms for satellite data processing. The science algorithms together with the framework are hosted on a Linux cluster.In this paper we present an architectural model and a system prototype for providing performance, reliability, and scalability of candidate hardware and software for a satellite data processing system. Furthermore, benchmarking results are presented for a selected number of science algorithms for the Geosynchronous Imaging Fourier Transform Spectrometer (GIFTS) instrument showing that considerable performance can be gained without sacrificing the reliability and high availability constraints imposed on the operational cluster system.