PC-based Solutions Research Articles

CNN Inference acceleration using low-power devices for human monitoring and security scenarios

Security is currently one of the top concerns in our society. From governmental installations to private companies and medical institutions, they all have to address directly with security issues as: access to restricted information quarantine control, or criminal tracking. As an example, identifying patients is critical in hospitals or geriatrics in order to isolate infected people, which has proven to be a non- trivial issue with the COVID-19 pandemic that is currently affecting all countries, or to locate fled patients. Face recognition is then a non-intrusive alternative for performing these tasks. Although FaceNet from Google has proved to be almost perfect, in a multi-face scenario its performance decays rapidly. In order to mitigate this loss of performance, in this paper a cluster based on the Neural Computer Stick version 2 and OpenVINO by Intel is proposed. A detailed power and runtime study is shown for two programming models, namely: multithreading and multiprocessing. Furthermore, 3 different hosts have been considered. In the most efficient configuration, an average of 6 frames per second has been achieved using the Raspberry Pi 4 as host and with a power consumption of just 11.2W, increasing by a factor of 3.3X the energy efficiency with respect to a PC-based solution in a multi-face scenario.

Implementation of FPGA-based real time novel chaotic oscillator

Currently, chaotic systems and chaos-based applications are commonly used in the engineering fields. One of the main structures used in these applications is the chaos-based signal generators. Chaotic signal generators have an important role, particularly in chaotic communication and cryptology. In this study, the Pehlivan-Wei chaotic system, which is a recently developed chaotic system, has been implemented with FPGA using three distinct algorithms (the Euler, Heun, and RK4) for the first time in literature. Numerical and HDL approaches are implemented by these three algorithms to compare the performance of each model for use in chaotic generators. In addition, the Lyapunov exponents and phase portraits of the system have been extracted for chaos analysis. RMSE analysis has been conducted on the chaotic generators, which are modeled using the Euler, Heun, and RK4 algorithms in order to observe error rates of each numerical algorithm in a comparative aspect. The performance of new chaotic system with various data sets has been analyzed. The operation frequency of the chaotic oscillators synthesized and tested for the Virtex-6 FPGA chip has been able to reach up to 463.688 MHz and the chaotic system has been able to calculate 300,000 data sets in 0.0284 s. However, PC-based algorithm having highest performance score can calculate 300,000 data sets in a period of 75.363 s. A comparison study has been performed on the performance of the FPGA-based and PC-based solutions to evaluate each approach.

A simple method of electrochemical lithium intercalation within graphite from a propylene carbonate-based solution

Electrochemical lithium intercalation within graphite from 1moldm−3 solution of LiClO4 in propylene carbonate (PC) was investigated at 25 and −15°C. Lithium ions were intercalated into and de-intercalated from graphite reversibly at −15°C despite the use of pure PC as the solvent. However, ceaseless solvent decomposition and intense exfoliation of graphene layers occurred at 25°C. The results of the Raman spectroscopic analysis indicated that the interaction between PC molecules and lithium ions became weaker at −15°C by chemical exchange effects, which suggested that the thermodynamic stability of the solvated lithium ions was an important factor that determined the formation of a solid electrolyte interface (SEI) in PC-based solutions. Charge–discharge analysis revealed that the nature of the SEI formed at −15°C in 1moldm−3 of LiClO4 in PC was significantly different from that formed at 25°C in 1moldm−3 of LiClO4 in PC containing vinylene carbonate, 3.27molkg−1 of LiClO4 in PC, and 1moldm−3 of LiClO4 in ethylene carbonate.

In Situ ECAFM and Raman Study on Interfacial Reactions between Graphite and PC-Based Solutions in Lithium Secondary Batteries

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An FPGA-Based Omnidirectional Vision Sensor for Motion Detection on Mobile Robots

This work presents the development of an integrated hardware/software sensor system for moving object detection and distance calculation, based on background subtraction algorithm. The sensor comprises a catadioptric system composed by a camera and a convex mirror that reflects the environment to the camera from all directions, obtaining a panoramic view. The sensor is used as an omnidirectional vision system, allowing for localization and navigation tasks of mobile robots. Several image processing operations such as filtering, segmentation and morphology have been included in the processing architecture. For achieving distance measurement, an algorithm to determine the center of mass of a detected object was implemented. The overall architecture has been mapped onto a commercial low-cost FPGA device, using a hardware/software co-design approach, which comprises a Nios II embedded microprocessor and specific image processing blocks, which have been implemented in hardware. The background subtraction algorithm was also used to calibrate the system, allowing for accurate results. Synthesis results show that the system can achieve a throughput of 26.6 processed frames per second and the performance analysis pointed out that the overall architecture achieves a speedup factor of 13.78 in comparison with a PC-based solution running on the real-time operating system xPC Target.

BDMI+양이온을 함유한 이온성 액체로부터 흑연으로의 전기화학적 리튬 삽입

흑연과 1-buthyl-2,3-dimethylimidazolium(BDMI)계 이온성 액체의 계면 반응을 이해하기 위하여 lithium bis(fluorosulfonyl)imide(LiTFSI)가 용해된 BDMI-TFSI 용액 중에서 전기화학 원자간력 현미경(electrochemical atomic force microscopy, ECAFM)을 이용하여 순환 전압전류법 전후에 있어서의 고배향성 열분해 흑연(highly oriented pyrolytic graphite, HOPG)의 표면을 in-situ로 관찰하였다. HOPG 전극에서 리튬의 가역적인 삽입과 탈리반응은 진행되지 않았으며, <TEX>$BDMI^+$</TEX> 양이온의 삽입에 의한 blister의 형성 및 그라펜 층의 파괴만이 관찰되었다. 한편, <TEX>$BDMI^+$</TEX> 양이온의 삽입 반응은 농도가 4.90 mol/kg인 LiTFSI-propylene carbonate(PC)를 15 wt% 함유하고 있는 BDMI-TFSI계에서는 일어나지 않았으며, 이 경우에는 가역적인 리튬의 삽입과 탈리반응이 진행 되었다. ECAFM 결과는 고농도의 PC계 용액이 solid electrolyte interface(SEI)를 형성함으로 인해 <TEX>$BDMI^+$</TEX> 양이온의 삽입을 막는 매우 효과적인 첨가제임을 나타내었다. In situ electrochemical atomic force microscopy (ECAFM) observations of the surface of highly oriented pyrolytic graphite (HOPG) was performed before and after cyclic voltammetry in lithium bis(fluorosulfonyl)imide (LiTFSI) dissolved in 1-buthyl-2,3-dimethylimidazolium (BDMI)-TFSI to understand the interfacial reactions between graphite and BDMI-based ionic liquids. The formation of blisters and the exfoliation of graphene layers by the intercalation of <TEX>$BDMI^+$</TEX> cations within HOPG were observed instead of reversible lithium intercalation and de-intercalation. On the other hand, lithium ions are reversibly intercalated into the HOPG and de-intercalatied from the HOPG without intercalation of the <TEX>$BDMI^+$</TEX> cations in the presence of 15 wt% of 4.90 mol/<TEX>$kg^{-1}$</TEX> LiTFSI dissolved in propylene carbonate (PC). ECAFM results revealed that the concentrated PC-based solution is a very effective additive for preventing <TEX>$BDMI^+$</TEX> intercalation through the formation of solid electrolyte interface (SEI).

A Parallel Hardware Architecture for Scale and Rotation Invariant Feature Detection

This paper proposes a parallel hardware architecture for image feature detection based on the scale invariant feature transform algorithm and applied to the simultaneous localization and mapping problem. The work also proposes specific hardware optimizations considered fundamental to embed such a robotic control system on-a-chip. The proposed architecture is completely stand-alone; it reads the input data directly from a CMOS image sensor and provides the results via a field-programmable gate array coupled to an embedded processor. The results may either be used directly in an on-chip application or accessed through an Ethernet connection. The system is able to detect features up to 30 frames per second (320times240 pixels) and has accuracy similar to a PC-based implementation. The achieved system performance is at least one order of magnitude better than a PC-based solution, a result achieved by investigating the impact of several hardware-orientated optimizations on performance, area and accuracy.

Real-time 3D computed tomographic reconstruction using commodity graphics hardware

The recent emergence of various types of flat-panel x-ray detectors and C-arm gantries now enables the construction of novel imaging platforms for a wide variety of clinical applications. Many of these applications require interactive 3D image generation, which cannot be satisfied with inexpensive PC-based solutions using the CPU. We present a solution based on commodity graphics hardware (GPUs) to provide these capabilities. While GPUs have been employed for CT reconstruction before, our approach provides significant speedups by exploiting the various built-in hardwired graphics pipeline components for the most expensive CT reconstruction task, backprojection. We show that the timings so achieved are superior to those obtained when using the GPU merely as a multi-processor, without a drop in reconstruction quality. In addition, we also show how the data flow across the graphics pipeline can be optimized, by balancing the load among the pipeline components. The result is a novel streaming CT framework that conceptualizes the reconstruction process as a steady flow of data across a computing pipeline, updating the reconstruction result immediately after the projections have been acquired. Using a single PC equipped with a single high-end commodity graphics board (the Nvidia 8800 GTX), our system is able to process clinically-sized projection data at speeds meeting and exceeding the typical flat-panel detector data production rates, enabling throughput rates of 40–50 projections s−1 for the reconstruction of 5123 volumes.

An Empirical Examination of the Importance of Defining the PHR for Research and for Practice

Objective Recent discourse surrounding PHRs conflates definitions of the technology and confuses both novices and experts. This matter assumes critical importance when research subjects are asked to respond to questionnaires in which the specific definition of the PHR is not given. We conducted this study to demonstrate that people have very different mental models of what a PHR represents and this affects their attitudes related to privacy and choice of specific PHR forms. Design Using data collected from a survey of both HIT stakeholders and a general population, we conduct descriptive and statistical analyses to demonstrate that various conceptualizations of PHRs exist. We use regression analysis and analysis of variance to test our hypotheses. Results We find that the nature of concerns regarding privacy and security of PHRs differ based on the individual's prior knowledge about and involvement with PHRs. We find that education influences choices regarding the type of PHR form-factor preferred but age does not. Beliefs are also dependent on the source of distribution of the PHR and as trust in an entity declines, consumers' choices regress towards isolated PHRs such as paper- or home PC-based solutions. Conclusion This study demonstrates that research related to PHRs must be very explicit in terms of defining the type of PHR. It also provides evidence of relationships between demographic characteristics leading to variations in PHR beliefs and choices. This work highlights some pitfalls of conducting research on PHRs and also presents new evidence about people's perceptions of PHRs. This study can be informative for both the design of PHRs and also for policy makers by surfacing barriers to adoption which could potentially slow the diffusion of this technology.

A real time framework for pc-based robot control under the QNX4 operating system

Even if highly reliable and endowed with powerful development tools nowadays industrial robot controllers don't usually allow the user to operate at the low level required in order to experiment control strategies and algorithms and to specify trajectories at the joint level. Such needs are mandatory in the robot control R & D area. Recently, the wide availability of computing power and operating systems with real-time capabilities offered the chance to develop low-cost PC-based solutions to overcome these limits. In this paper we present the design of a modular architecture for PC-Based robot control and contextually evaluate the use of QNX4 as a operating system for control applications. The main features of the designed controller have been employed for the motion control of a 4 d.o.f. reconfigurable parallel robot.

A model for a PC-based, universal-format, multimedia digitization system: Moving beyond the scanner 1

Rationale and Objectives. Digitizing images for use in case presentations based on hardcopy films, slides, photographs, negatives, books, and videos can present a challenging task. Scanners and digital cameras have become standard tools of the trade. Unfortunately, use of these devices to digitize multiple images in many different media formats can be a time-consuming and in some cases unachievable process. The authors’ goal was to create a PC-based solution for digitizing multiple media formats in a timely fashion while maintaining adequate image presentation quality. Materials and Methods. The authors’ PC-based solution makes use of off-the-shelf hardware applications to include a digital document camera (DDC), VHS video player, and video-editing kit. With the assistance of five staff radiologists, the authors examined the quality of multiple image types digitized with this equipment. The authors also quantified the speed of digitization of various types of media using the DDC and video-editing kit. Results. With regard to image quality, the five staff radiologists rated the digitized angiography, CT, and MR images as adequate to excellent for use in teaching files and case presentations. With regard to digitized plain films, the average rating was adequate. As for performance, the authors recognized a 68% improvement in the time required to digitize hardcopy films using the DDC instead of a professional quality scanner. Conclusions. The PC-based solution provides a means for digitizing multiple images from many different types of media in a timely fashion while maintaining adequate image presentation quality.

Electrochemical Intercalation of Lithium Ion within Graphite from Propylene Carbonate Solutions

Electrochemical lithium intercalation within graphite was investigated in propylene carbonate (PC) containing different concentrations, 0.82 and 2.72 mol dm - 3 , of bis(perfluoroethylsulfonyl)imide, LiN(SO 2 C 2 F 5 ) 2 . Lithium ion was reversibly intercalated into and deintercalated from graphite in the latter concentrated solution in spite of the use of pure PC as a solvent, whereas ceaseless solvent decomposition and intensive exfoliation of graphene layers occurred in the former solution. X-ray diffraction analysis revealed that a stage I graphite intercalation compound was formed alter being fully charged in the 2.72 mol dm - 3 solution. The results of Raman analysis indicated that no free PC molecules are present in the concentrated solution, which suggested that the ion/solvent interactions would be an important factor that determines the ability of stable surface film formation in PC-based solutions.

Electrochemical scanning tunneling microscopy analysis of the surface reactions on graphite basal plane in ethylene carbonate-based solvents and propylene carbonate

In order to elucidate the mechanism of surface film formation on graphite negative electrodes of rechargeable lithium-ion batteries, topographical changes of the basal plane of a highly oriented pyrolytic graphite were observed in a few electrolyte solutions under polarization by electrochemical scanning tunneling microscopy. In 1 M LiClO 4/ethylene carbonate (EC) + diethyl carbonate, a hill-like structure of ∼ 1 nm height appeared on the surface of highly oriented pyrolytic graphite at 0.95 V versus Li/Li +, and then changed at 0.75 V to irregular shaped blister-like features with a maximum height of ∼ 20 nm. In 1 M LiClO 4/EC + dimethoxyethane, hemispherical blisters of ∼ 20 nm height appeared at 0.90 V. These morphology changes, hill and blister formation, were attributed to the intercalation of solvated Li − ions into graphite interlayers and to the accumulation of its decomposed products, respectively. On the other hand, only rapid exfoliation and rupturing of graphite layers were observed in 1 M LiClO 4/propylene carbonate (PC), which was considered to be responsible for ceaseless solvent decomposition when graphite electrodes are charged in PC-based solutions. From the observed topographical changes, it was concluded that the intercalation of solvated Li + ions is a necessary step for stable surface film formation on graphite.

Frontal program for a PC-based solution of unsymmetric matrices using a buffered pivot search

In this paper, an algorithm for efficient implementation of the frontal method for unsymmetric matrix equations is presented. The pivot choice is made from a buffer of variables eligible to be eliminated. A minimum buffer size is maintained until the assembly of the last element. A PC-based computer program in QBASIC is included. The program can be run on a PC with DOS 5.0 or later versions. The program is integrated into a finite element solution of fluid flow using triangular elements.

Statistical software packages for PCs — A market survey

The increase of statistical software applications for PCs is caused by decreasing hardware costs and dramatically enhanced PC performance. Whereas in the past the domain of statistical computing has been reserved to mainframe solutions, a great number of new software packages for PCs have come out in the last five years. Therefore, the producers of established mainframe software were also forced to offer PC-based solutions. By limiting a market analysis to products with a medium set of well known statistical methods, the immense number of available products is reduced to about fifty systems. We ordered an evaluation copy of these systems to test the numerical quality, the system speed, and the performance of several procedures. Seventeen packages were made available for an extensive examination. This paper will (1) discuss the problems and the solutions of obtaining a complete and correct datamatrix that describes the entire market and (2) present the results of a comparative market analysis.