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A fiber Bragg grating (FBG) sensing system was used to online monitor the temperature at the surface of / inside the liver tissue of a rabbit under nanosecond pulse electric field (nsPEF). Single point measurement between the electrodes and multi-point measurement surrounding one electrode were both carried out. Experimental results show that, due to equally spaced (Δt=0.5 s) 300 ns-pulses with E=20 kV/cm at a repetition rate of 4 Hz, the temperature rise in the rabbit liver tumor usually does not exceed ΔΤ=6°C for 300 pulses. Theoretical analysis of Joule heating model fits well with the experimental results. Both direct measurements and theoretical modelling demonstrated that nsPEF could not deliver enough energy to heat the treated tissue significantly, thus a hyperthermic effect on the tissue can be excluded during this kind of treatment with much high electric field strength and extremely short duration.

Lower-limb exoskeletons have gained considerable interest in recent years for strength augmentation and load carrying. Many methods have been proposed for strength augmentation. Among these approaches, Sensitivity Amplification Control (SAC) algorithm was first proposed in the augmentation applications of Berkeley Lower Extremity Exoskeleton (BLEEX) and achieve significant performance. It just need the information from the exoskeleton robot, thus reducing the complexity of exoskeleton system. However, SAC algorithm is based on the accuracy dynamic models of exoskeleton in different phases which is hard to obtain. This paper presents a novel control strategy: hybrid control. In the proposed hybrid control strategy, swing leg and stance leg are controlled separately. For the control of swing leg, zero force control strategy is employed to let exoskeleton shadow the motion of pilots smoothly. For the control of stance leg, zero load control strategy is utilized to reduce the gravity of load, which lead pilot to move freely and feel more comfortable. We design a exoskeleton system named HUman-powered Augmentation Lower EXoskeleton (HUALEX) and demonstrate the control efficiency of hybrid control in simulation platform. The experimental results show that the proposed hybrid control strategy can reduce interaction force between the pilot and the exoskeleton efficiently.

Compressive spectral imaging combines traditional spectral imaging technique with compressive sensing and its preliminary application ability has been early explored by the usage on the occasions such as machine-vision and biomedical imaging. In this paper, spatio-spectral reconstruction based on sparse recovery method is presented and its performance is estimated. Simulating imaging experiment is carried out by using AVIRIS visible band data and specific module based on two-step iterative shrinkage/thresholding algorithm is built so as to execute reconstruction for the data cube. Statistical index is adopted so as to judge data fidelity quantitatively so that the effect of the regularizer index optimization and frame shooting number increasing on the improvement of reconstructed data fidelity can be distinctly revealed. The spatio-spectral featuring of different ground species are also evaluated by visual judgment on restored images and spectral curves.

In view of underwater acoustic complex broadband signal and power amplification matching difficulties of problem, there presenting underwater acoustic broadband power amplifier and matching system generator methods based on virtual instrument technology, and designed the multifunction underwater acoustic broadband amplifier signal generator and controller system for underwater sound transmitting transducer the choice, the impedance matching network choice as well as the transmitter condition message control based on Lab VIEW. The system can be customized according to your demand to choose whether launching continuous or pulse signal, and it will further implementation on launches amplifier power, signal forms, impedance matching network parameters. The result of actual tests shows the underwater acoustic broadband amplifier signal generator and controller system could reduce the hardware expenses, also the system is advantageous for the promotion by using simple operation.

Many-core SoC (MCSoC) design is one of chip design trends and challenges. Modeling and simulation for large scale MCSoC design is the key to get it right the first time. NoC is the most important component of future MCSoC. A novel modeling tool, MCVP-NoC (Many-Core Virtual Platform with Networks-on-Chip support) was designed for large scale MCSoC modeling, and can be used in design space exploration, early software development and system verification. MCVP-NoC was built on SystemC, OVP(Open Virtual Platform) and TLM2.0, integrated with Orion2.0 for power and area estimation. MCVP-NoC can run real software code, and can be used to evaluate the performance of the MCSoC design under real application load.

Remote sensing imaging spectrometry is widely used in fields such as atmosphere survey, mineral discovery, forest surveillance and so on. The signal-to-noise ratio (SNR) of an imaging spectrometer reflects its radiance response and relates closely to its acquired image quality. Due to limited throughput, current slit-based hyperspectral imaging spectrometer stands a dilemma between its spectral resolution and SNR. For an airborne hyperspectral imaging spectrometer, the SNR is required to be in the order of hundred while the intentional spectral resolution requirement is met. The evaluation of SNR is of significance to its overall design and indice determination. Varying from panchromatic camera, for an imaging spectrometer, not a single SNR value but many a value due to different wavelengths has to be worked out. The atmospheric transmission model is built and the shooting circumstance is simulated by use of the MODerate resolution TRANsmission (MODTRAN). The SNR reduction due to the input throughput cut caused by the entrance slit is specially taken into account and environmental factors such as flight height, solar altitude angle and surface albedo can be set as required. For an imaging spectrometer that works in both visible and near-infrared band, two detectors are adopted. Each one collects visible or near-infrared images separately and its noise is calculated individually. The resulting SNR of the imaging spectrometer of the whole working band can be used as the basis to carry out feasible airborne spectrometer indice determination.

Intra prediction is the most important technology in H.264/AVC intra frame encoder. But there is extremely complicated data dependency and an immense amount of computation in intra prediction process. In order to meet the requirements of real-time coding and avoid hardware waste, this paper presents a parallel and high efficient H.264/AVC intra prediction architecture which targets high-resolution (e.g. 4k×2k) video encoding applications. In this architecture, the optimized intra 4×4 prediction engine can process sixteen pixels in parallel at a slightly higher hardware cost (compared to the previous four-pixel parallel architecture). The intra 16×16 prediction engine works in parallel with intra 4×4 prediction engine. It reuses the adder-tree of Sum of Absolute Transformed Difference (SATD) generator. Moreover, in order to reduce the data-dependency in intra 4×4 reconstruction loop, a block-level and mode-level co-reordering strategy is proposed. Therefore, the performance bottleneck of H.264/AVC intra encoding can be alleviated to a great extent. The proposed architecture supports full-mode intra prediction for H.264/AVC baseline, main and extended profiles. It takes only 163 cycles to complete the intra prediction process of one macroblock (MB). This design is synthesized with a SMIC 0.13µm CMOS cell library. The result shows that it takes 61k gates and can run at 215MHz, supporting real-time encoding of 4k×2k@40fps video sequences.

Adaptive Block-size Transform (ABT) has been added to H.264/AVC standard with the Fidelity Range Extension. In this paper, we apply this ABT concept to our FME design and propose a full-mode FME architecture based on 8×8/4×4 adaptive Hadamard Transform. This technique can avoid unifying all variable block-size blocks into 4×4-size blocks and improve the encoding performance. We also exploit the linearity of Hadamard Transform in quarter-pel refinement and decrease the cycles caused by the second long search process. In architecture level, we employ two interpolating engines that can support 8-pel and 4-pel input to time-share one SATD (Sum of Absolute Hadamard Transform) Generator. These strategies can increase parallelism and reduce the cycles efficiently. Besides, this design can support full modes, which guarantees the encoding performance. Experimental results show that our design can achieve real-time processing for QFHD@30fps at the operation frequency of 320MHz with 444.6K gates hardware.

This paper presents a hardware-efficient and high-throughput quantization implementation for H.264/AVC high profiles encoder. The constant multiplication in quantization is accomplished by time-multiplexed multiple-constant multipliers (MUX-MCM). By rational pipeline decision, the proposed design manages to achieve a high throughput at a low area cost. Synthesized with SMIC0.18µm technology, the proposed design reaches a maximum operating frequency of 250Mhz with a throughput of 1Gpixels/sec at the hardware cost of 28.56 Kgates.

The signal processing flow for the MTF test bench that is based on Fourier analysis method is presented. The signal processing flow mainly consists of three parts that are Fourier analyzing, background correction and system attenuation elimination. The center of the pinhole area is recognized automatically and the line spread functions (LSF) of both sagittal and tangential directions are calculated. Second-order fast Fourier transform is executed so that a primary two-direction MTF result is gained. Either auto Fourier-domain background correction or manual time-domain background correction is executed. The attenuation of the tested MTF result due to the influence of the detector and pinhole is eliminated finally. A commercially available 50-mm plano-convex audit lens is tested as the sample to validate the accuracy of the signal processing flow of the MTF test bench. The test error is below 0.01 under 2001p/mm.

The surface potential distribution of buried X80 steel under cathodic protection was calculated by finite element method. After comparing the results of simulation and experiment, the advantages and disadvantages of the numerical simulation method used in the present paper were discussed.

We have investigated the possibility to instigate discharges in tissue and evaluated their potential for medical applications. With appropriate electrode configurations, we were able to generate either corona discharges or spark discharges in the tissue itself by applying nominal rectangular high voltage pulses of 30-ns and 380-ns duration, respectively. The shorter pulses were provided by a Blumlein line pulse generator, and the longer pulses were generated with a Blumlein pulse forming network. Sub-microsecond pulsed electric fields have demonstrated remarkable potential in the treatment of solid tumors1. We assumed that the efficacy of the method can be improved by reactive species that are generated in a corona. Changing the polarity of the voltage-bias applied to the center needle of a coaxial delivery system, we were able to compare treatments with and without discharge. However, our experiments did not show any significant advantage of a corona discharge for our configuration and treatment parameters. With the longer pulse it is possible to generate a spark discharge between the tips of two needle electrodes, which are inserted into the tissue. Depending on tissue type (muscle, liver, fat) and pulse amplitude, several tissue-conditioning pulses had to be applied before breakdown could be achieved. When a spark was initiated, the breakdown voltage was lower than expected for liquids but higher than expected for air (at atmospheric pressure). The visual inspection of the tissue damage showed a highly localized incision, which runs between the tips of the needle electrodes. The preliminary histological analysis suggests that the damage is mostly caused by the Shockwave associated with the spark.

As global 3G shipment catches up with GSM/EDGE and becomes the mainstream of cellular, a drastic reduction of the cost premium in 3G eBOM becomes imperative, where the RF subsystem features prominently. Full Duplex operation has so far necessitated external LNAs and inter-stage SAW filters in both Tx and Rx paths in commercial 3G phones. Recent publications, where techniques have been proposed to improve RF transceiver design, to enable Tx [1–5] or Rx [5–8] SAW filters to be removed, highlight the attention they now attract from the industry. Here we report a WCDMA transceiver (XCVR), complete with on-chip LNAs and free of both Rx and Tx SAW filters without resorting to calibration or above-passivation inductors, and having reached proven maturity in volume production. Integration of DC-DC converters not only takes eBOM reduction a step further, but also marks a breakthrough by such a noisy function into a cellular RF XCVR of the most sensitive kind in terms of spurious response.

Wireless sensor networks (WSNs) have wide applications due to these sensor nodes ease of deployment.But the security of WSNs is still an important issue. Some existed approaches mainly rely on cryptography to ensure data authentication and integrity. These approaches only address part of the problem of security in WSNs. However, these approaches are not sufficient for the unique characteristics and novel misbehaviors or abnormal behaviors encountered in WSNs. In this paper we introduce an implicit security authentication scheme technique ,which can authenticate the sensor nodes based on actions they would carry out anyway. From our preliminary findings support that this is a meaningful approach, whether used to increase usability or increase security in WSNs.

Nanosecond pulsed electric fields have demonstrated remarkable potential as tumor therapy. The application of 300-ns pulses with amplitudes of 40–50 kV/cm to melanomas grown in mice caused complete remission of the tumors. It is believed that the primary process that kills the tumor cells is the induction of apoptosis. Electrical models predict that for the application of shorter pulses, higher field strengths are required to trigger this process. By increasing field strength, the field eventually exceeds the dielectric strength of the tissue, especially in the vicinity of the small-diameter needle electrodes used for the exposure. Consequently, discharge phenomena, such as coronas can occur in the tissue. Such non-thermal plasmas, i.e. streamers, could likely assist a tumor therapy by generating reactive oxidative species. We have investigated the regression of tumors that were treated with a coaxial electrode configuration comprised of a 0.4 mm needle electrode in the center of a solid ring electrode of 4 mm radius. A 30-ns/24-kV high voltage pulse of either positive or negative polarity can be applied to the center electrode with respect to the grounded ring-electrode. With positive bias, strong corona discharges can be observed along the needle, while for the opposite polarity, these are either negligible or do not occur. Tumor regression was compared for both conditions and also with results for a 5-needle array of similar dimensions. Preliminary data could not determine any significant immediate advantages of either configuration.

Image fusion techniques of remote sensing data can integrate different spatial and spectral information. ALOS is a new data source with two optical sensors onboard, PRISM and AVNIR-2. PRISM has high spatial resolution, while AVNIR-2 is of multi-spectral resolution. Study on ALOS data fusion methods has potentials for promoting the applications of ALOS data. This paper aimed to explore a proper method for data fusion purpose. Five fusion methods, Brovey, PCA, SFIM, HPF and Gram-Schmidt, were tested. Visual and statistical comparisons were conducted to evaluate the effect of different fusion algorithms in terms of spatial resolution enhancement and spectral information maintenance. We found overall results of Gram-Schmidt in improving spatial resolution details and preserving spectral information were superior to the others. PCA was good at enhancing textural information, but caused much color distortion. SFIM best preserved the spectral abundance, but was less optimal at improving spatial information.

The traditional approach of providing security in sensor network was cryptography and authentication. However, the conventional approach of security based on cryptography and authentication alone is not sufficient for the unique characteristics and novel misbehaviors encountered in wireless sensor networks. In this paper, we use a general tool which borrowed from other domains such as economics, statistics and data analysis. With this approach, we propose a task and trust framework for sensor networks where nodes maintain reputation for other nodes of several different tasks and use it to evaluate their trustworthiness. We will show that this framework provides a scalable, diverse and a generalized approach to recognize all types of misbehavior resulting from malicious or faulty sensor nodes. Our framework has more simple trust computation than ATSN and more suitable for scarce power resource sensor nodes. The simulation results and analysis show that our framework can detect the malicious nodes fast if having abnormal result while executing some task.

Summary form only given. Over the last several years pulse power technology has developed into a novel and innovative time domain nanotechnology as a new modality to treat cancer. The technology treats cancer in the absence of drugs by generating non-ionizing radiation with nanosecond pulsed electric fields (nsPEFs or nanopulses) that are high in power (gigawatts) and low in energy (millijoules). They can induce apoptosis and cause loss of vascular viability contributing to infarctive tumor death in a temperature-independent manner. NsPEFs have effects distinct from conventional electroporation (EP) used in irreversible EP and electrochemotherapy with bleomycin. Nanopulses affect intracellular structures and functions while having unique, non-EP effects on plasma membranes. Unlike cancer therapies that induce necrosis through lethal cryotherapy or hyperthermia, such as radiofrequency ablation, nanopulses convey intense, high power, non-thermal electric fields to the tumor mass, sparing adjacent tissues and resulting in the elimination of tumors. NsPEFs induced apoptosis in all tumor cells tested in vitro. In addition, nsPEFs induced apoptosis in fibrosarcoma tumors and significantly reduced tumor size. Apoptosis is a form of programmed cell death that is altruistic cell suicide that eliminates cells that are senescent, damaged, diseased or not needed such that surrounding cells are spared the damage by inflammation. During apoptosis cells undergo an orchestrated disassembly of cell structure and function by proteases called caspases. The apoptotic cells are phagocytized by other cells such that the cell raw materials can be recycled. Apoptosis is the antithesis of death by necrosis, where cell membrane integrity fails and cells leak their contents into the surrounding environment leading to inflammation, pain and scarring. Indicators of apoptosis in fibrosarcoma tumors included caspase activation and DNA fragmentation (degradation). The use of nsPEFs as a non-thermal, non-ionizing radiation modality without chemotherapeutic agents will provide a basis for future clinical studies to treat cancers. The application of nsPEFs is safe and relatively inexpensive. Unlike chemotherapy it does not have systemic side effects and unlike surgery it is minimally invasive and leaves no scars. The therapeutic application of nsPEFs can provide an inexpensive, non-invasive, new, novel, and effective method to the arsenal for cancer treatment strategies.

Our initial in vitro (HL-60 cells) and in vivo (B16-F10 murine) studies showed nanosecond pulsed electric fields (nsPEFs) caused intracellular changes and melanoma involution, respectively. We wanted to describe the morphologic changes in cell ultrastructure and investigate the mechanism for change due to nsPEFs in B16-F10 melanoma tumors in SKH-1 mice. We injected B16-F10 cells into 120 female SKH-1 mice to derive melanoma tumors. After multiple nsPEF treatments (40 kV/cm field strength; 5 ns rise time; 300 ns duration), morphologic changes of melanoma size, shape, tumor nesting pattern, blood vessel structure and cell ultrastructure were observed. Nuclear changes were recorded with light-and transmission electron-microscopy (TEM). Apoptosis in situ was detected by several immunohistochemistry (IHC) methods: (1) terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL); (2) caspase 3, 6 and 7; and (3) histone H2AX. After multiple nsPEF treatments the melanoma blood supply was disrupted and melanomas shrank an average of 90% within two weeks. TEM showed increased rough endoplasmic reticulum and condensed dark-staining nucleoli; TUNEL presented fluorescent increase. Together these suggest post-treatment apoptotic activity, which was concurrently allied with increased caspase 3, 6 and 7, and histone H2AX fluorescence (DNA damage) after pulsing. Our study shows that blood flow and apoptotic changes play a central role in the biological effects caused by nsPEFs. Therefore nsPEFs may have application potential in cancer therapy, gene regulation and biophysical research by non-invasively disrupting intracellular components and inducing apoptosis in malignant tumors.

In our initial study, a major change found in the melanomas treated by nsPEFs was an immediate reduction in blood flow to the tumor and up to 90% tumor shrinkage within two weeks following a cumulative PEF exposure time of 120 mus. The reduction of existing vessels and the lack of new blood vessel formation into and within the melanoma tumors stimulated the present research on angiogenesis. We investigated the vascular formation and the expression of angiogenic growth factors in melanomas treated by multiple nsPEFs: 40 kV/cm; 5 ns rise time; 300 ns duration to identify mechanisms inducing tumor involution. Samples of B16-F10 melanoma cells injected into 66 female SKH-1 mice were analyzed by tissue microarray technology. Tumor blood vessels were studied by confocal microscopy with double fluorescent staining for endothelial cells (CD31) and pericytes (smooth muscle actin). Intra-tumoral microvessel density (IMD) was assessed by immunohistochemistry with CD31 (marks large vessels), CD34 (medium vessels) and CD105 (microvessels). Vascular endothelial growth factor (VEGF) and platelet-derived endothelial cell growth factor (PD-ECGF) expressions were also determined by Western-blot to show change in up-stream control factors. Double fluorescence staining showed decreased tumor blood network formation. IMD density assessed by CD31, CD34 and CD105 had significantly lower expression in treated compared to control groups (Table 1, p

Nanosecond pulsed electric fields (nsPEF) have been shown to penetrate into living cells to permeabilize intracellular organelles and release Ca2+ from the endoplasmic reticulum. They provide a new approach for physically targeting intracellular organelles with many applications, including initiation of apoptosis, enhancement of gene transfection efficiency and inhibiting tumor growth. We have been working with the murine melanoma model system and here we show that 40 kV/cm electric field pulses 300 nanoseconds in duration can rapidly stimulate pyknosis, reduce blood flow and fragment DNA in murine melanoma tumors in vivo with a total field exposure time of 1.8 microseconds. Three treatments of 100 pulses each results in a mean tumor size regression of 90% within two weeks. Another round of treatments at this time can completely eliminate the melanoma. This new therapy is the first to simultaneously trigger pyknosis and reduce tumor blood flow.

A 4GHz integer-N frequency synthesizer is realized in a 0.13/spl mu/m CMOS technology. It has a 400kHz reference frequency and 40kHz loop bandwidth such that 2GHz quadrature LO signals can be generated after a divide-by-two, with channel raster of 200kHz. The measured in-band phase noise is -74dBc/Hz @4kHz offset. A self-regulated charge pump is proposed to improve matching as well as charge sharing. Reference spurs are thereby kept below -55dBc over the VCO tuning voltage from rail to rail. The requirements for UMTS transceiver have been fulfilled with an overall power consumption of 9.5mW, which is the lowest reported to date. Core area of the chip is as small as 0.2mm/sup 2/.

A 2.5 Gb/s laser diode driver IC to be used in SDH system has been realized by using a standard 0.35-/spl mu/m CMOS process. The modulation current is as high as 60 mA and temperature respect is considered. The chip area is 0.9 mm/sup 2/.