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Microwave tomography is an effective technique to estimate material distribution, where inverse scattering analysis is performed on the assumption that accurate information on the incident field is known for a measurement curve as well as in the target region. In reality, however, the information may often be unobtainable due to multiple scattering between the transmitting antenna and the target object, or existence of unwanted waves and obstacles. In this paper, a method to extract information on incident fields from measured total field data is proposed. The validity of the proposed method is verified on 2D TMz problems, where a cylindrical, a square, and an L-shape homogeneous object are employed as a target object. Furthermore, it is shown that the method is available even when there are unwanted obstacles outside the measurement curve.

Contains fulltext : 215333.pdf (Publisher’s version ) (Closed access) BACKGROUND: Patients with stable coronary artery disease and diabetes with previous percutaneous coronary intervention (PCI), particularly those with previous stenting, are at high risk of ischaemic events. These patients are generally treated with aspirin. In this trial, we aimed to investigate if these patients would benefit from treatment with aspirin plus ticagrelor. METHODS: The Effect of Ticagrelor on Health Outcomes in diabEtes Mellitus patients Intervention Study (THEMIS) was a phase 3 randomised, double-blinded, placebo-controlled trial, done in 1315 sites in 42 countries. Patients were eligible if 50 years or older, with type 2 diabetes, receiving anti-hyperglycaemic drugs for at least 6 months, with stable coronary artery disease, and one of three other mutually non-exclusive criteria: a history of previous PCI or of coronary artery bypass grafting, or documentation of angiographic stenosis of 50% or more in at least one coronary artery. Eligible patients were randomly assigned (1:1) to either ticagrelor or placebo, by use of an interactive voice-response or web-response system. The THEMIS-PCI trial comprised a prespecified subgroup of patients with previous PCI. The primary efficacy outcome was a composite of cardiovascular death, myocardial infarction, or stroke (measured in the intention-to-treat population). FINDINGS: Between Feb 17, 2014, and May 24, 2016, 11 154 patients (58% of the overall THEMIS trial) with a history of previous PCI were enrolled in the THEMIS-PCI trial. Median follow-up was 3.3 years (IQR 2.8-3.8). In the previous PCI group, fewer patients receiving ticagrelor had a primary efficacy outcome event than in the placebo group (404 [7.3%] of 5558 vs 480 [8.6%] of 5596; HR 0.85 [95% CI 0.74-0.97], p=0.013). The same effect was not observed in patients without PCI (p=0.76, pinteraction=0.16). The proportion of patients with cardiovascular death was similar in both treatment groups (174 [3.1%] with ticagrelor vs 183 (3.3%) with placebo; HR 0.96 [95% CI 0.78-1.18], p=0.68), as well as all-cause death (282 [5.1%] vs 323 [5.8%]; 0.88 [0.75-1.03], p=0.11). TIMI major bleeding occurred in 111 (2.0%) of 5536 patients receiving ticagrelor and 62 (1.1%) of 5564 patients receiving placebo (HR 2.03 [95% CI 1.48-2.76], p

We present an inverse scattering method using only total electric field data on an observation surface with no knowledge of incident fields. An initial-boundary value problem is set up whose solution coincides with that of the original scattering problem in the interior region bounded by the observation surface if and only if a medium inside the observation surface is the same as that of the original one. A cost functional consisting the stored energy of the misfit field between the original problem and the boundary value problem with an estimated object is introduced to solve the inverse problem. Preliminary numerical examples are provided to assess the proposed inversion approach.

In this paper, a Frequency-Dependent Forward-Backward Time-Stepping (FD-FBTS) inverse scattering technique is used for reconstruction of homogeneous dispersive object. The aim of the technique is to reconstruct the relative permittivity at infinite frequency, static relative permittivity and static conductivity of the homogeneous dispersive object simultaneously. The technique utilizes iterative finite-difference time-domain (FDTD) method for solving inverse scattering problem in time domain. The minimization of the cost functional is carried out utilizing Dai-Yuan nonlinear conjugate-gradient algorithm. The Frechet derivatives of the augmented cost functional are derived analytically with respect to scatterer properties. Numerical results for reconstruction of two-dimensional homogeneous dispersive illustrate the performance of the proposed technique.

Background Hypertension, diabetes, dyslipidemia and smoking are established coronary risk factors for coronary heart disease in the general population. However, in Japanese patients with acute myocardial infarction (AMI), the impact of the number of coronary risk factors on in-hospital morality remains unclear. Methods The Japan Acute Myocardial Infarction Registry (JAMIR) is a nationwide real-world database. We examined the association between the number of coronary risk factors and in-hospital mortality. Results Data were obtained from total of 20462 AMI patients (mean age, 68.8 ± 13.3 years old; 15281 men, 5181 women). The prevalence of hypertension increased with advancing age, while the prevalence of smoking decreased with advancing age. The prevalence of diabetes and dyslipidemia were highest in middle age. A majority (76.9%) of the patients with AMI had at least 1 of these coronary risk factors. Overall, the number of coronary risk factor was relatively less in older subjects and women under 50 years old. Crude in-hospital mortality rates were 10.7%, 10.5%, 7.2%, 5.0% and 4.5% with 0, 1, 2, 3 and 4 risk factors, respectively. After adjusting for age and sex, there was an inverse association between the number of coronary risk factors and the in-hospital mortality (adjusted odds ratio [1.68; 95% confidence interval, 1.20–2.35] among individuals with 0 vs. 4 risk factors). Conclusion In the present study of Japanese patients with AMI, who received modern medical treatment, in-hospital mortality was inversely related to the number of coronary risk factors. To investigate the underlying reasons for these findings, further studies are needed.

International audience; The structural health monitoring of cultural heritages is addressed in this paper. The arising inverse problem is solved through the Learning-by-Examples (LBE) paradigm, exploiting data collected by a Wireless Sensor Network (WSN). More in detail, low-cost and low-size sensing devices are spread over the scenario to be monitored, allowing environmentaldata as well as acceleration and vibration information to be acquired and processed by means of a Support Vector Machine (SVM) in order to detect the presence/absence of a damage in the monitored structure. The proposed approach has been preliminary validated in a laboratory controlled environment, demonstrating promising performance.

Background The lymphatic system has been suggested to play an important role in cholesterol metabolism and cardiovascular disease. However, the relationships of vascular endothelial growth factor‐C ( VEGF ‐C), a central player in lymphangiogenesis, with mortality and cardiovascular events in patients with suspected or known coronary artery disease are unknown. Methods and Results We performed a multicenter, prospective cohort study of 2418 patients with suspected or known coronary artery disease undergoing elective coronary angiography. The primary predictor was serum levels of VEGF ‐C. The primary outcome was all‐cause death. The secondary outcomes were cardiovascular death, and major adverse cardiovascular events defined as a composite of cardiovascular death, non‐fatal myocardial infarction, and non‐fatal stroke. During the 3‐year follow‐up, 254 patients died from any cause, 88 died from cardiovascular disease, and 165 developed major adverse cardiovascular events. After adjustment for established risk factors, VEGF ‐C levels were significantly and inversely associated with all‐cause death (hazard ratio for 1‐ SD increase, 0.69; 95% confidence interval, 0.60–0.80) and cardiovascular death (hazard ratio, 0.67; 95% confidence interval, 0.53–0.87), but not with major adverse cardiovascular events (hazard ratio, 0.85; 95% confidence interval, 0.72–1.01). Even after incorporation of N‐terminal pro‐brain natriuretic peptide, contemporary sensitive cardiac troponin‐I, and high‐sensitivity C‐reactive protein into a model with established risk factors, the addition of VEGF ‐C levels further improved the prediction of all‐cause death, but not that of cardiovascular death or major adverse cardiovascular events. Consistent results were observed within 1717 patients with suspected coronary artery disease. Conclusions In patients with suspected or known coronary artery disease, a low VEGF ‐C value may independently predict all‐cause mortality.

This chapter introduces the applications of the Flexible Reliability Reconfigurable Array (FRRA) processors, which is presented in Sect. 3.4, in a non-von Neumann architecture, and discusses its advantages when it is used in the Internet of Things (IoT) applications. FRRA is an embodiment of the concept of embedded automaton that we introduce as an essential element for building the IoT. We will start by looking at the role played by embedded system processors and point out that employing non-von Neumann architecture is inevitable (essential) to accomplish the speed/power performance required for embedded system applications. The major target application of embedded microprocessor is the IoT, and space-born sensor applications are quoted in this chapter as examples of the IoT. Space systems are somewhat special but are typical IoT applications which require dependability as an essential feature. Another important aspect of the embedded automaton based on the FRRA architecture is the contribution of behavioral synthesis technology. Practical application implementation on the reconfigurable processor is realized with the maturity of a high-level behavioral synthesis technology called CyberWorkBench (CWB).

In data-parallel computing that uses a graphic processing unit (GPU), processing of large data requires that multiple GPUs be used in the computer to increase its execution performance. Increasing processing performance by using multiple computing resources has been enabled by the development of computing frameworks based on a directed acyclic graph (DAG). However, their performance degrades in out-of-core processing, which often occurs in processing of large data on GPUs with limited memory capacity. The GPU data input/output (I/O) for data swapping between host memory and GPU memory during the execution of a user DAG is usually a performance bottleneck. A computing framework called "Victream" is proposed to overcome this drawback. It uses a novel scheduler that involves two methods to minimize the total amount of GPU data I/O of data swapping. First, it performs locality-aware scheduling. When it schedules a task, it selects one that requires the minimum amount of data swapping and reuses as much of the data residing in GPU memory as possible. Second, it extends the locality-aware scheduling so that GPUs can execute data prefetching. Prefetching data that are swapped out from a GPU enables efficient use of bottleneck GPU I/O resources. To prefetch the input data of future tasks, it is required to determine the schedule of future tasks. Victream's scheduler (hereafter, the Victream scheduler) extends the locality-aware scheduling so that it can schedule future tasks to enable data prefetching that is executed in the way that minimizes the amount of data I/O of data swapping. Evaluation of a Victream prototype showed that the performance of Victream is better than that of conventional frameworks by up to 117%.

An inverse scattering algorithm without information of incident field using edge-reserving regularization is proposed. Since inverse scattering problems are nonlinear and ill-posed, an edge-preserving regularization technique is preferred to solve the problems. The numerical simulation is examined for reconstructing “Austria profile”. The edge-preserving regularization technique yields successful reconstruction with more accurate relative permittivity profile.

Network Function Visualization (NFV) is becoming a new networking architecture for telecom carriers. NFV achieves network functions with software and commercial off the shelf (COTS) servers instead of dedicated hardware. While the software-based approach is expected to reduce costs, it could cause performance issues. CPU-FPGA tightly coupled architectures may be available in COTS servers in the near future. This paper proposes accelerating NFV application leveraging such a CPU-FPGA architecture. The proposed method of acceleration uses a data plane development kit (DPDK) ring queue, which is often used in network software, as the communication interface between the FPGA and CPU. We propose two optimizations for ring operation and table lookup operation to efficiently use the bus between FPGA and CPU. We evaluated the proposed method with an actual CPU+FPGA based platform, and an NFV application, i.e., vCPE. The results revealed that the evaluation system could accommodate 2 × 40-GbE Internet traffic, and could increase capacity as a vCPE server by x1.33.

The Brevibacillus brevis BBR47_28440 gene (referred to as ddlR) encodes an MocR/GabR family transcriptional regulator consisting of an N-terminal helix-turn-helix DNA binding domain and a C-terminal aminotransferase-like domain. The ddlR gene is located just upstream of the d-alanyl-d-alanine ligase gene (ddl) in the B. brevis genome, and these two genes form an operon. Gel-shift assays indicated that purified DdlR binds specifically to the DNA region that includes putative -35 and -10 regions of the ddlR promoter. A 6-bp inverted repeat that overlaps the -10 region of the ddlR promoter was found to be important for the binding. In vivo reporter assays confirmed that DdlR is an activator of the ddlR-ddl operon. Spectroscopic analyses indicated that purified DdlR is a pyridoxal 5'-phosphate binding transcriptional regulator that has dipeptide binding ability for d-alanyl-d-alanine, the enzymatic product of Ddl, and glycylglycine. DdlR is capable of forming a dipeptide-pyridoxal 5'-phosphate external aldimine, but it lacks aminotransferase activity. Bioinformatic analyses suggest that DdlR-mediated transcriptional regulation of ddlR and ddl may occur in multiple bacterial systems such as Actinobacteria and Bacillus species.

Bacillus subtilis GabR is a transcriptional regulator consisting of a helix-turn-helix N-terminal DNA-binding domain, a pyridoxal 5'-phosphate (PLP)-binding C-terminal domain that has a structure homologous to aminotransferases, and a linker of 29 amino acid residues. In the presence of γ-aminobutyrate (GABA), GabR activates the transcription of gabT and gabD, which encode GABA aminotransferase and succinate semialdehyde dehydrogenase, respectively. We expressed N-terminal and C-terminal domain fragments (named N'-GabR and C'-GabR) in Escherichia coli cells, and obtained N'-GabR as a soluble monomer and C'-GabR as a soluble dimer. Spectroscopic studies suggested that C'-GabR contains PLP and binds to d-Ala, β-Ala, d-Asn and d-Gln, as well as GABA, although the intact GabR binds only to GABA. N'-GabR does not bind to the DNA fragment containing the GabR-binding sequence regardless of the presence or absence of C'-GabR. A fusion protein consisting of N'-GabR and 2-aminoadipate aminotransferase of Thermus thermophilus bound to the DNA fragment. These results suggested that each domain of GabR could be an independent folding unit. The C-terminal domain provides the N-terminal domain with DNA-binding ability via dimerization. The N-terminal domain controls the ligand specificity of the C-terminal domain. Connection by the linker is indispensable for the mutual interaction of the domains.

Memcached has been widely accepted as a technology to improve the response speed of web servers by caching data on DRAMs in distributed servers. Because of its importance, the acceleration of memcached has been studied on various platforms. Among them, FPGA looks the most attractive platform to run memcached, and several research groups have tried to obtain a much higher performance than that of CPU out of it. The difficulty encountered there, however, is how to manage large-sized memory (gigabytes of DRAMs) from memcached hardware built in an FPGA. Some groups are trying to solve this problem by using an embedded CPU for memory allocation and another group is employing an SSD. Unlike other approaches that try to replace memcached itself on FPGAs, our approach augments the software memcached running on the host CPU by caching its data and some operations at the FPGA- equipped network interface card (NIC) mounted on the server. The locality of memcached data enables the FPGA NIC to have a fairly high hit rate with a smaller memory. In this paper, we describe the architecture of the proposed NIC cache, and evaluate the effectiveness with a standard key-value store (KVS) benchmarking tool. Our evaluation shows that our system is effective if the workload has temporal locality but does not handle workloads well without such a characteristic. We further propose methods to overcome this problem and evaluate them. As a result, we estimate that the latency improved by up to 3.5 times over software memcached running on a high performance CPU.

A novel inverse scattering approach to estimate the permittivity profile of an unknown scatterer of interest without explicit knowledge on incident wave illuminating the scatterer is presented. The approach is based on the field equivalence principle. In the interior equivalent problem, where original field exists in the interior region while in the exterior region a zero field, a scatterer in the interior region should be the same as the original one. If the original scatterer is replaced by a different one, the total field in the exterior region becomes a non-zero field. From this observation, a functional which is the magnitude of the total electric field on a closed curve surrounding the interior region is introduced. The functional is minimized by the conjugate gradient method. Numerical simulations for some two dimensional scatterers are carried out to show the effectiveness of the proposed method.

Background The prevalence of atrial fibrillation (AF) is high in elder subjects. Our previous observational study suggested that vitamin K antagonist (VKA) promotes aortic valve degeneration, a principal cause of aortic stenosis in the elderly, and that angiotensin receptor blocker (ARB) attenuates its progression. This study aimed to prospectively investigate these observations in non-valvular AF patients. Methods Of enrolled 430 patients with calcification on no or one aortic valve leaflet, all of the planned 4-year follow-up data were obtained in 122 non-valvular AF patients treated with warfarin (warfarin group) and 101 patients with cardiovascular diseases and without AF and prescription of warfarin (non-warfarin group). Results Despite higher atherosclerotic risks in the non-warfarin group, 2 or 3 newly calcified leaflets emerged during 4 years in 18.0% of patients in the warfarin group and in 6.9% in the non-warfarin group (p = 0.014). Aortic valve area (AVA) did not significantly change in the non-warfarin group during the follow-up, but tended to decrease in the warfarin group (p = 0.057). Non-vitamin K antagonist oral anticoagulant got available in Japan after this study started, and warfarin was discontinued in 15 patients of the warfarin group. The reduction of AVA was significant in the remaining 107 patients on the continuous warfarin treatment (p = 0.002). The effects of ARB on AVA were obscure. Conclusion Major bleeding associated with VKA is well recognized. This study suggests that the development of aortic valve degeneration is another risk of long-term use of VKA in non-valvular AF patients with no or mild aortic valve degeneration.

In this paper, a breast cancer detection system is proposed. The system consists of 24 wideband printed inverted-F antennas. The reflection and transmission coefficients of the wideband printed inverted-F antennas are compared to the conventional one. The proposed system has uniform reception level from 0.6GHz to 4.0GHz.

An inverse scattering approach using only total electric field data is developed for reconstructing electrical parameters of unknown scatterers. Two interior boundary value problems are set up whose solutions coincide with each other if and only if a medium inside the observation surface is the same as that of the original scattering problem. A cost functional of misfit between the two solutions is introduced to solve the inverse problem and its gradient is derived explicitly. Numerical examples are provided to assess the proposed inversion approach. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:137–141, 2015

A 68-year-old woman with a history of hypertension was admitted to our hospital because of dyspnea during physical exertion. Echocardiography demonstrated impaired left ventricular systolic function, and her ejection fraction was reduced to 30%. Coronary angiography did not show significant stenosis. Endomyocardial biopsy showed only nonspecific findings without noncaseating granulomas. Cardiac magnetic resonance (CMR) imaging showed transmural late gadolinium enhancement on the basal part of the left ventricle. 18F-Fluorodeoxyglucose positron emission tomography (18F-FDG PET) showed abnormal focal uptake specific to the left ventricle; no abnormal manifestations in other organs were observed. The CMR and 18F-FDG PET features could not rule out either sarcoidosis or malignant lymphoma. Therefore, we conducted open-chest myocardial biopsy to differentiate between the two possible diseases. Histopathological findings showed noncaseating epithelioid cell granuloma, confirming isolated cardiac sarcoidosis. This is an example of a challenging case of diagnosing isolated cardiac sarcoidosis. .

This brief presents an efficient complex event-processing framework, designed to process a large number of sequential events on field-programmable gate arrays (FPGAs). Unlike conventional structured query language based approaches, our approach features logic automation constructed with a new C-based event language that supports regular expressions on the basis of C functions, so that a wide variety of event-processing applications can be efficiently mapped to FPGAs. Evaluations on an FPGA-based network interface card show that we can achieve 12.3 times better event-processing performance than does a CPU software in a financial trading application.

An inverse scattering approach based on the field equivalence principle is developed for reconstructing the electrical parameters of a stratified medium using only electric field time-domain data measured at two observation points in presence and absence of the medium. The magnetic field data at the observation points are calculated from the electric field data by solving two equivalent problems for the incident and scattered fields. By noting that the field of an equivalent problem for the total field in the interior region between two observation points is null in the exterior region, the functional of the electrical parameters is introduced. A genetic algorithm is applied for minimization of the functional to estimate the parameters. Numerical simulations demonstrate the effectiveness of the approach. © 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2013.

International audience; Imaging techniques exploiting sparseness-regularized formulations emerged in the last few years as powerful and effective retrieval methods in several heterogeneous scenarios [1] including structural monitoring, non-destructive testing and evaluation, ground penetrating radar imaging, and biomedical diagnosis [2-8]. The success of the this class of algorithms, which are often collectively indicated as Compressive Sensing (CS) [9], is motivated by several concurring factors, including their accuracy, robustness, numerical efficiency, capability to handle several different contexts (e.g., including transverse-magnetic [2] and transverse-electric problems [3], single-/multi-frequency data [2, 4], isotropic/anisotropic media [1]) in a seamless way, and the availability of efficient implementations of many different solvers [1]. On the other hand, CS techniques are not general-purpose imaging algorithms. Their application requires the problem at hand to comply with some fundamental assumptions [1], including the fact that the unknown (e.g., the contrast [8] or equivalent currents [9]) is sparse in the employed basis. Early applications of CS methods, which used simple pixel-bases to expand the unknowns, addressed only those scenarios were the object is composed by few isolated pixels [2]. Nevertheless, it is well known that sparsity is not an absolute concept, but it is always in relation with the representation basis [1]. The use of different expansion bases [10] has been then proposed to enable more complex profiles to be imaged [7]. Unfortunately, such techniques always assume that some knowledge on the target profile is available, so that this a-priori information can be exploited to define the most suitable expansion basis to be adopted [7]. A different perspective is considered in this paper to enable the application of CS methodologies when no prior information on the class of targets under investigation is available. More specifically, a large alphabet of candidate bases is generated off-line, and for each basis a candidate reconstructions are carried out in parallel “online” by the CS retrieval tool. The retrieved profiles are then compared, and a sparsity-based criterion is adopted in turns to select the most reliable reconstruction (among those obtained by the different bases). Preliminary numerical experiments will be shown to assess the accuracy and numerical efficiency of the proposed imaging methodology

International audience; Summary form only given. There is nowadays an increasing attention and request towards the study and development of systems and techniques for increasing the human safety and security in all aspects of the everyday life. In this framework, the possibility to perform a non-invasive inspection of structures or objects by means of non-destructive testing and evaluation (NDT-NDE) technologies is of particular interests in several applicative fields, ranging from civil engineering to biomedicine, up to aeronautic and nuclear industries [1]. One of the main limitations of the current NDT-NDE approaches is the high computational burden that prevents the real-time or almost real-time investigation of the structure under test (SUT). As a matter of fact, these techniques, aimed at minimizing a suitable cost function that quantifies the mismatch between the acquired data and the retrieved/simulated data, are based on iterative deterministic [2] stochastic [3, 4] or also hybrid optimization approaches that are time-consuming.

International audience; The capability to describe, design, and configure complex devices on a multi-scale basis (e.g., combining their descriptors on a macro-scale, such as the device geometry, and on a micro/nano-scale, such as on the constituting material features) is a very important task in those applicative scenarios where the features of the overall systems can be obtained only as combination of information obtained at different discretization scales [1]. Unfortunately, multiscale design turns out one of the most complex problems in electromagnetic engineering, as it requires the availability of suitable synthesis strategies able to correctly handle the huge number of Degrees-of-Freedom (DoFs) of the arising device in a computationally efficient and effective way [1].

International audience; Summary form only given. In the last few years, the possibility to engineer the properties of artificial Metamaterials at microwave, THz, and optical frequencies has represented one of the key factors enabling the study, development, and demonstration of effective electromagnetic cloaks [1]. Indeed, several devices have been proposed which are able to manipulate the wave propagation not only to reduce radar cross section, but also to mitigate mutual coupling in close radiators and to reduce antenna backscattering [1]. In this framework, “perfect cloaks” have been initially designed through Transformation Electromagnetics (TE) methodologies [1]. Such techniques are based on the formulation of the cloaking problem as a “geometry deformation” one, in which the target is made invisible by “bending” the wave around it [1]. Unfortunately, the effectiveness of TE-based devices, numerically demonstrated in several different scenarios [2-5], can be obtained only if inhomogeneous and anisotropic permittivity and permeability tensors can be synthesized. In order to overcome this issue, alternative cloaking strategies based on the Scattering Cancellation principle have been proposed [6-10]. In this case, the cloak is made of a set of patterned metasurfaces covering the scatterer, whose properties are not aimed at bending the wave, but rather at enforcing that the combined scattering contributions of the target and the mantle cancel out [6-10]. Despite their effectiveness and potentialities [6-10], standard scattering cancellation methods are usually applied to thin dielectric/metallic cylinders since the design of multi-layer cloaks, required for “large” targets, is a theoretically and computationally challenging task (also because of the arising mutual coupling among the layers). To address this challenge, an instance of the System-by-Design paradigm [11] will be proposed in this work. Towards this end, the design of multi-layer mantle cloaks based on patterned metasurfaces and able to reduce the radar cross section of large dielectric cylinders will be reformulated as a task-oriented SbD problem. More specifically, (i) the objective will be the minimization of the scattering coefficients of the overall structure (taking into account mutual coupling effects), which will be encoded in a suitable cost function, and (ii) the degrees-of-freedom will be the patterns of each metasurface comprised in the cloak. Thanks to the capability of the SbD paradigm to formulate the design problem in a modular way, the most proper methodology will be adopted for each one of the functional blocks constituting the synthesis process [11]. The effectiveness of the resulting SbD-enhanced devices will be demonstrated through selected numerical experiments.

Forward-Backward Time-Stepping Method (FBTS method) is a technique to solve time domain inverse scattering problem. An incident pulse is radiated to unknown object. The scattering wave is measured at M points. A similar measurement is carried out at N different incident points. Total number of measured data is M × N. In FBTS method, the estimated field is calculated by FDTD method. The number of calculation on FDTD method is required only the number of incident points. Most on computing time by FBTS method is occupied by calculation of FDTD method. Therefore the method that the incident pulse was emitted at the same time at N different point was suggested. In this method, computing time becomes about 1/N compared with a usual FBTS method. However accuracy of reconstruction image degrades. In this research, time-delay FBTS method is proposed. The number of the measured electric field is M × N like a normal FBTS method. In the case of a linear medium, a theorem of the superposition holds good. Therefore, the total electric fields at each observation points are got by adding measured field for each incidence pulse when a pulse was radiated at the same time at different incident points. It is not necessary to be simultaneous the start time of electromagnetic pulse emitted from each incident point. That is, the start time of the radiation pulse can be changed by the incident points. Difference between the start times of the radiation pulses is referred to as a time-delay. Different time-delay is given the different total electric field. It's possible to get a measured field of many simultaneous incidences by introducing different time-delay to the same measured field. It's possible to improve the accuracy of the reconstruction image by using some delay times. Also, when time delay becomes longer than observation time to radiation of a pulse, presented method becomes same as a usual FBTS method. The validity of the presented technique is indicated by some numerical simulations.

Time reversal imaging methods have received considerable attention since they yield accurate location estimate of point scatterers. Up to now, most time reversal methods have focused on detection and localization of point-like or small targets [1, 2] and not dealt with estimation of electrical parameter profile of scatterers. We have proposed a gradient based time-reversal imaging technique which can reconstruct electrical parameter distributions of the unknown object [3]. This method is based on the field equivalence principle and does not require the explicit knowledge of the incident field [4]. In this problem, the following functional of the parameters equation is to be minimized equation where equation is the region exterior to the measurement surface S and T is the measurement time. The field u n (p; r, t) is the solution of Maxwell equation for time reversed fields with the estimated parameters p under the n-th illumination. The quantity c is the light speed of the background. Due to the nonlinearity of the inverse scattering problem, the solution based on gradient methods often gets trapped into a local minimum. In order to avoid this problem, the filtered forward-backward time-stepping (FBTS) technique is used [5]. In this technique, the measured total field data is processed through a low-pass filter with several cut-off frequency sequences and these filtered data are solved by FBTS method. Numerical simulations show the effectiveness of the proposed method.

An inverse scattering problem of determining the electrical property of an unknown dielectric object is considered. The electromagnetic wave generated by an impressed electric current with a short duration time illuminates the dielectric object. The measured data of the total field, the sum of the incident and scattered fields, over an observation surface S is used to reconstruct the electrical property distributions of the object without explicit information on the incident field. Using the tangential component of the electric field over the observation surface S, we can set up a boundary value problem which is equivalent to the original direct scattering problem in the interior region Ω i bounded by the surface S. Suppose that the total field data is measured over the observation surface S till the time t = T by which almost all the total energy leaves the interior region Ω i through the surface S and the field in the interior region becomes negligibly small. In this interior equivalent problem, the electrical property distribution must be the same as in the original scattering problem, i.e., the scattering object placed in the interior region must be the same as the original one. If a different object is placed in the interior region, reflection occurs on the surface in order for the total field to satisfy the boundary value. The reflected wave keeps bouncing in the interior region and remains even after the end time T of measurement. Noting this fact, we introduce the following functional of the electrical property distribution p(r): equation where η is the intrinsic impedance of free space, and Eeq(p; r, T) and Heq(p; r, T) are the electric and magnetic fields at the time t = T of the boundary value problem with the electrical property distribution p. If the distribution p is identical to the original one, the equivalent electric and magnetic fields are null at the time t = T. Therefore, the inverse problem is reduced to finding a minimizer of the functional Q(p). We apply a conjugate gradient method to the minimization problem. Several numerical simulations show the validity of the proposed method.

In this paper, an approach based on the field equivalence principle for obtaining the information of the incident field from total field data is presented. In general, the incident field is not easy to know because it is related to not only the impressed source but also the characteristics of the transmitting antenna and the surrounding environment of the source. By using this approach, the incident electric field is calculated from only total field data measured on a closed line, which is very useful for inverse scattering. Preliminary numerical simulations for some two dimensional scatterers show that the fields extracted from total field data are almost equal to the incident fields illuminating a scatterer of interest.

Power analysis for IoT devices is strongly required to reduce power consumption and realize secure communications. In this paper, we propose a scalable and small-sized power analyzer with signal-averaging noise reduction for low-power IoT devices. The proposed power analyzer reduces a wide frequency range of noises by using a signal averaging method and is implemented on just a 2cmx3cm board, which is the smallest size among the other existing power analyzers for IoT devices. It further has the following advantages: (a) It has a two-level amplifier that amplifies current signals adaptively depending on their magnitude. Hence maximum readable current can be increased with keeping minimum readable current small enough. (b) If long-time analysis is required, it can be partitioned into several analysis segments. The proposed power analyzer can measure currents and voltages of each analysis segment by using a small amount of data memories. After that, by combining these analysis segments using a timer module, we can obtain long-time analysis results. We have analyzed power and energy consumption of encryption processes of AES block cipher on the IoT device and demonstrated that the proposed power analyzer has only 1.8% measurement error compared with a high-precision oscilloscope.

A novel inverse scattering approach in time domain is presented for reconstructing electrical parameters of a stratified slab. The approach based on the field equivalence principle does not need explicit information of incident fields. Considering a problem equivalent to the original scattering problem inside the region bounded by the measurement points, a cost functional of electrical parameters of the slab is introduced. The minimization of the functional is achieved by a genetic algorithm. Numerical simulations of reconstructing the relative permittivity of a stratified dielectric slab demonstrate the efficacy of the proposed method., IEICE Electronics Express, 9(15), pp.1243-1248; 2012

We report a case of clonic-tonic seizures diagnosed using an implantable loop recorder, a device for detecting cardiac arrhythmias. A 65-year-old man was referred to our hospital for loss of consciousness with myotonic jerks during sleep. He had experienced several similar episodes. No family history of sudden death was evident, and no structural heart disease was present. Coronary angiography with intracoronary acetylcholine (ACh) showed neither organic stenosis nor vasospastic angina. Ventricular tachyarrhythmias were not induced by programmed electrical stimuli. Sleep electroencephalography, brain magnetic resonance imaging and magnetic resonance angiography revealed no specific findings. We implanted a loop recorder to monitor rhythm abnormalities. One month later, an attack occurred at night. His wife recognized the episode and activated the implantable loop recorder. No arrhythmia was recorded, but myopotentials characteristic of tonic-clonic seizures were detected.

A hybrid method of forward–backward time-stepping algorithm and genetic algorithm is applied to microwave imaging for breast cancer detection.A two-dimensional numerical breast phantom with high contrast between fat and fibroglandular tissues and low contrast between fibroglandular and tumor tissues is used to assess the efficacy of the proposed method. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:438–442, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25699

In this paper, an inverse scattering technique referred to as the filtered forward-backward time-stepping method is applied to microwave imaging for breast cancer detection. A two-dimensional numerical breast phantom (derived from MR images) with high contrast between fat and fibroglandular tissues, and low contrast between fibroglandular and tumor tissues are used to assess the efficacy of the proposed method., 2010 URSI International Symposium on Electromagnetic Theory (EMTS 2010) : Berlin, Germany, 2010.08.16-2010.08.19, 2010 URSI International Symposium on Electromagnetic Theory, pp.1046-1049; 2010

An iterative reconstruction algorithm for three-dimensional (3-D) microwave tomography by using time-domain microwave data is applied to detect breast tumor. A numeric breast model with randomly distributed glandular tissues (random size and permittivity) with a tu- mor is designed for the calculation of synthetic microwave data. An \air phantom" consisting of a section of polyvinyl chloride (PVC) pipe fllled with styrofoam and a thin glass cylinder is constructed for col- lecting microwave data in laboratory. The \breast" and \air phantom" are reconstructed. Reconstruction results show that the \tumor" in the

Scheduling, an essential step in high-level synthesis, is an intractable process. Traditional heuristic scheduling methods usually search schedules directly in the entire solution space. In this paper, we propose the idea of searching within an intermediate solution space (ISS). We put forward a max-flow scheduling method that heuristically prunes the solution space into a specific ISS and finds the optimum of ISS in polynomial time. The proposed scheduling algorithm has some unique features, such as the correction of previous scheduling decisions in a later stage, the simultaneous scheduling of all the operations, and the optimization of more complicated objectives. Aided by the max-flow scheduling method, we implement the optimization of the IC power-ground integrity problem at the behavior level conveniently. Experiments on well-known benchmarks show that without requiring additional resources or prolonging schedule latency, the proposed scheduling method can find a schedule that draws current more stably from a supply, which mitigates the voltage fluctuation in the on-chip power distribution network.

This paper discusses the reconstruction of the subsurface from radar data using a time-domain reconstruction method. Before the reconstruction is conducted, data preprocessing is carried out. The preprocessing transforms measured data transmitted and received by 3-D dipole antennas into equivalent data excited and received by 3-D ideal electric dipoles and, then, into equivalent data excited and received by 2-D ideal electric dipoles. Distributions of permittivity, conductivity, and permeability are reconstructed from the preprocessed data by a 2-D forward-backward time-stepping waveform inverse scattering technique. Two 2-D examples of permittivity and conductivity reconstruction from synthetic noisy and field borehole radar data are demonstrated to show the effectiveness of the proposed method

A new forward-backward time-stepping (FBTS) method using gradient-based optimization method has been proposed for inverse scattering problems. This method is based on the field equivalence principle and does not require the explicit knowledge of the incident field. Due to the nonlinearity of the inverse scattering problem, the solution based on gradient methods often gets trapped into a local minimum. In order to avoid this problem, the measured total field data is processed through a low-pass filter with several cut-off frequency sequences in the FBTS algorithm. Numerical simulations show the effectiveness of the proposed method.

A 53-year-old woman with a history of allergic disease was admitted to our hospital because of syncope induced by sustained ventricular tachycardia. The clinical course and the laboratory data did not correspond to those of acute myocarditis. Although eosinophils in the peripheral blood count were not increased, the diagnosis of eosinophilic myocarditis was made following a right ventricular endomyocardial biopsy that showed a remarkable infiltration of eosinophils. While giant cells were another histopathological feature of this case, they were considered to be an expression of the disease severity. This is a rare case of eosinophilic myocarditis, without peripheral eosinophilia. Learning objective: Eosinophils in the peripheral blood usually increase in eosinophilic myocarditis. We describe a case of eosinophilic myocarditis without hypereosinophilia. Even in the absence of hypereosinophilia, endomyocardial biopsy should be performed during the investigation of unexplained myocardial disease.>

This paper introduces an example of real-time “big data” processing systems accelerated by field-programmable gate arrays (FPGAs), which will open up a novel design field for digital circuit engineers. Contrary to the perception that software on commodity servers dominates such large-scale processing requirements, there are various chances for utilizing hardware for the acceleration. One of the most promising applications is complex event processing (CEP), which requires hardware-based acceleration due to it having to process massive amounts of data in real time. We propose a design flow for compiling software-oriented event language into highly parallelized and pipelined CEP circuits, which enables our system to achieve a strikingly high performance of 20 Gbps. A sophisticated mechanism for integrating archives of previously arrived data with streams of current events also makes the FPGA-accelerated processing system applicable to a wide range of realistic “big data” applications.

This paper discusses the reconstruction of permittivity, permeability and conduc- tivity from ground-penetrating radar (GPR) data by using a time-domain reconstruction tech- nique. The objective functional is deflned as the integration over time of some power of weighted residual between observed and calculated data. The power of the objective functional is any number larger than 1. The gradients of the functional to the unknown parameters are derived. A synthetic reconstruction example from multi-ofiset noise-free and noisy data is illustrated by using L2, L1:6 and L1:2 norm of objective functional. A reconstruction example from experimen- tal common-ofiset data is also demonstrated. In this example L2 and L1:2 norms are used. Both synthetic and experimental reconstructed results show that the reconstructed results by using low-order norms are better than those by using the conventional Euclidean norm. DOI: 10.2529/PIERS060802223029

As the volume of data that web services handle is becoming larger, many web service providers are utilizing memcached, an in-memory key-value store to improve their web server's performance. While memcached usually runs on a server with a high performance processor, various hardware platforms has been evaluated for running memcached in order to achieve higher performance. Recently, several works that use FPGAs have successfully achieved higher performance than Xeon. These works, however, struggles to utilize a large memory with FPGAs. In this paper, we propose a system that enables us to overcome this problem and enhances memcached by caching a part of software memcached's commands and data to the network interface card equipped with an FPGA and a DRAM. Our evaluation showed that the NIC cache has less than 30% of hit rate for workload with Latest key selection distribution, and 30% to 60% for Zipf distribution workloads.

Independent predictors of the severity of coronary atherosclerosis are ill defined. We sought to determine the predictors and examine the association of impaired glucose tolerance with stenosis severity. Four hundred thirty-seven patients were studied who underwent coronary angiography for suspected coronary artery disease. Serum concentrations of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDLc), lipoprotein(a) [Lp(a)] and apolipoproteins (Apo A-I and Apo B) were measured and low-density lipoprotein cholesterol (LDLc) concentration was calculated. Except the patients treated for diabetes mellitus (DM), patients were classified into three groups such as normal glucose tolerance (NGT), impaired glucose tolerance (IGT) and DM by glucose tolerance test. Coronary atherosclerosis index (CAI) representing the severity of coronary atherosclerosis was determined by summation of the stenosis score of all lesions on coronary angiograms. Results indicated that age, total amount of cigarettes smoked, Apo B/Apo A-I, and LDLc/HDLc correlated with CAI, whereas HDLc and Apo A-I concentrations inversely correlated with CAI. TC, TG, Lp(a), LDLc, Apo B concentrations and body mass index did not correlate with CAI. One- and two-hour plasma glucose concentrations and the area of plasma glucose concentration under the curve at the glucose tolerance test did not correlate with CAI, revealing that post-challenge glycemia is not associated with stenosis severity. CAI in IGT patients was significantly lower than that in DM patients but did not differ from that in NGT patients, indicating that IGT does not affect the stenosis severity. Multivariate analysis showed that age, male gender, Apo B/Apo A-I, DM, systemic hypertension, and total amount of cigarettes smoked were independent predictors of CAI.

We have proposed a time-domain forward-backward time-stepping (FBTS) method for reconstructing 3D structures in highly absorptive media. The reconstruction speed is greatly dependent on the number of transmitters. In this paper, we propose a source-group method to speed up the reconstruction. In the source-group method, multiple transmitters arranged at different positions are excited simultaneously, and receivers collect the wave fields. To compare the reconstruction results, three kinds of reconstructions from 16 conventional single transmitter-multiple receiver data sets, four source-group multiple-receiver data sets, and four conventional single-transmitter multiple-receiver data sets are carried out. Reconstruction by the source-group method is several times faster than (and the reconstructed results are almost the same as) those of the first kind of reconstruction, and they are much better than those of the third kind. © Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 67–71, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21263