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Designs for high performance PAL-based imaging systems

APPLIED OPTICS 2012年第21期51卷 5310-5317页

作者： Hui, Dong Zhang, Mei Geng, Zheng Zhang, Yunfang Duan, Jingyuan Shi, Ancun Hui, Li Fang, Qing Liu, Yuliang Chinese Acad Sci Inst Automat State Key Lab Management & Control Complex Syst Beijing Peoples R China Chinese Acad Sci Inst Semicond Optoelect Syst Lab Beijing 100083 Peoples R China

In this study, we investigate methods to optimize the design of a panoramic annular lens (PAL) system. The design details of a PAL surveillance system, an anamorphic PAL surveillance system, a phone camera with a PAL attachment, and a PAL endoscope system are described. All these designs are optimized using a standard optical software package (Zemax). The results combine very good image quality with a modulation transfer function above 0.3, which is within the cutoff frequency of sensor chips. (C) 2012 Optical Society of America

关键词： SHCBP1 gene programmable logic arrays HIGH-PERFORMANCE toroidal lens Image quality SURVEILLANCE SYSTEMS PAL(LANGUAGE) Cutoff frequency LRIT1 gene Imaging systems Software packages modulation transfer function

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Privacy-Preserving Physical-Layer Authentication for Non-Orthogonal Multiple Access Systems

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IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 2022年第4期40卷 1371-1385页

作者： Xie, Ning Zhang, Qihong Chen, Junjie Tan, Haijun Shenzhen Univ Guangdong Key Lab Intelligent Informat Proc Shenzhen 518060 Peoples R China Shenzhen Univ Shenzhen Key Lab Media Secur Coll Elect & Informat Engn Shenzhen 518060 Peoples R China

This paper addresses the problems of both authentication and privacy in a Non-Orthogonal Multiple Access (NOMA) system by using a privacy-preserving Physical-Layer Authentication (PLA) scheme. The prior scheme has the following limitations: no privacy, low authentication performance, management problem of different secret keys, and constraint to the two-user scenario. In this paper, we propose two privacy-preserving PLA schemes: the Privacy-Preserving PLA (PP-PLA) scheme and the Enhanced Privacy-Preserving PLA (EPP-PLA) scheme, which improve both the privacy and authentication performance as compared to the prior scheme. The fundamental difference between the EPP-PLA and PP-PLA schemes is how to encrypt the source message of a certain user while the other operations of the two proposed schemes keep the same. We provide the theoretical analysis of the proposed schemes in terms of robustness, compatibility, privacy, and security, and derive their closed-form expressions. Moreover, we provide the theoretical comparisons between the proposed schemes and the prior scheme. We optimize the parameters of the proposed schemes to achieve both message-rate fairness and authentication-accuracy fairness. We implement the proposed schemes and conduct extensive performance comparisons through simulations. Experimental results show that the theoretical results perfectly match the corresponding simulation results. Specifically, we take the second user, acting as an administrator for a NOMA system with three users, as an example, where SNR = 16 dB. In comparison with the prior scheme, both proposed schemes have the same compatibility, whereas they improve the robustness by 4.72%. Moreover, the EPP-PLA and PP-PLA schemes improve the security by 32.8%, whereas they improve the privacy by 3000.75% and 1000.75%, respectively.

关键词： NOMA Privacy programmable logic arrays Authentication Robustness MISO communication Receivers Physical layer authentication non-orthogonal multiple access robustness compatibility privacy security

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EVALUATING programmable logic DEVICES

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IEEE CIRCUITS AND DEVICES MAGAZINE 1990年第3期6卷 45-48页

作者： KOELLING, TK Intel Corporations Programmable Logic Device Operation Folsom CA

The use of the combinational/register coordinate system as a graphical way of measuring programmable logic devices (PLDs) in terms of gates and registers is reviewed. It is assumed that the I/O resources of the PLD, which constitute a third axis, are adequate. This allows the analysis to be restricted to an x-y plane fixed along the z-axis. The device's application area, which is the area bounded by its combinational and register capability, is discussed, and methods for calculating the application range are described. Three brief examples demonstrate the ways in which the coordinate system might be used in CAD tools that automate the PLD design process.< >

关键词： programmable logic devices logic devices programmable logic arrays Flip-flops Coordinate measuring machines Field programmable gate arrays Circuit synthesis Strontium Aggregates logic design

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PLA FOLDING ALGORITHM FROM COMPATIBILITY RELATIONS

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ELECTRONICS LETTERS 1985年第21期21卷 984-986页

作者： BISWAS, NN Department of Electrical Communication Engineering Indian Institute of Science Bangalore India

The letter reports an algorithm for the folding of programmable logic arrays. The algorithm is valid for both column and row folding, although it has been presented considering only the simple column folding. The pairwise compatibility relations among all the pairs of the columns of the PLA are plotted in a matrix called the compatibility matrix of the PLA. A foldable compatibility matrix (FCM), a new concept defined in the letter, is then derived from the compatibility matrix. Once an FCM is obtained, the ordered pairs of fold-able columns and the reordering of the rows are readily determined.

关键词： logic circuits integrated logic circuits logic design cellular arrays logic design methods row folding programmable logic arrays PLA folding algorithm pairwise compatibility relations column folding foldable compatibility matrix

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A simple finite element model to study the effect of plasma plume expansion on the nanosecond pulsed laser ablation of aluminum

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APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 2019年第9期125卷 1页

作者： Wang, Yeqing Hahn, David W. Mississippi State Univ Dept Aerosp Engn Mississippi State MS 39762 USA Univ Florida Dept Mech & Aerosp Engn Gainesville FL 32611 USA Univ Arizona Dept Aerosp & Mech Engn Tucson AZ 85721 USA

In this paper, a simple model was proposed using finite element analysis (FEA) with a commercial FEA software ABAQUS to simulate the two-dimensional (2-D) laser heat transfer in an aluminum material. Without relying on the conventional hydrodynamic model, the proposed model not only predicts the evolutions of the temperature field and ablation profiles in the target material, but also provides an estimation on the evolutions of electron density, plasma temperature, and plasma absorption coefficient. The assumptions used in the model include the local thermal equilibrium and additional assumptions regarding the average plasma temperature and vapor density. The assumptions allowed the laser heat transfer equation to be solved together with the Saha-Eggert equation and conservation equations of matter and charge. When compared to the existing hydrodynamic models, the proposed model solves a less number of nonlinear equations and hence is computationally more efficient. The proposed FE model was employed to study the plasma-shielding effect on PLA produced by a 193 nm Excimer laser and a 266 nm Nd:YAG laser. The predictions of ablation depths, electron density, and plasma temperature agree well with the experimental data. Moreover, effects of the laser intensity and the average plasma temperature on the efficiency of the plasma shielding during PLA were also investigated and discussed in this study.

关键词： Laser Ablation Vapour density conservation equations plasma plume flow Aluminum Material NANOSECOND PULSE programmable logic arrays thermal equilibrium nonlinear equations Finite element method Excimer lasers aluminium plasma temperature

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GRAFCET - A POWERFUL TOOL FOR SPECIFICATION OF logic CONTROLLERS

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IEEE TRANSACTIONS ON CONTROL SYSTEMS TECHNOLOGY 1995年第3期3卷 253-268页

作者： DAVID, R Laboratoire ďAutomatique de Gre Institut National Polytechnique de Grenoble France

Basically, a logic controller is a discrete-event system whose purpose is to control the behavior of a process which is itself (seen by the controller as) a discrete-event system, taking into account the state of this process and other information coming from an operator or from other systems. In the early 1970's, the need to describe increasingly complex logic controllers was becoming evident, since the programmable logic controllers (PLC) were becoming more powerful and more extensively used, This paper shows how Grafcet can be used for this purpose. Grafcet is a tool, drawing its inspiration from Petri nets (a general purpose mathematical tool allowing various discrete-event systems to be described), whose aim is the specification of logic controllers. It is the basis of the Sequential Function Chart (SFC), an International Standard in 1987. This paper, introductory in nature, explains the Grafcet model using the classical-state table model and presents a method for interpreting grafcets.

关键词： Control systems Discrete event systems programmable control programmable logic arrays programmable logic devices Chemical industry Relays Microprocessors Food industry Machinery production industries

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Morphology and properties of biodegradable and biosourced polylactide blends with poly(3-hydroxybutyrate-co-4-hydroxybutyrate)

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POLYMER COMPOSITES 2012年第6期33卷 850-859页

作者： Han, Lijing Han, Changyu Zhang, Huiliang Chen, Shan Dong, Lisong Chinese Acad Sci Changchun Inst Appl Chem Key Lab Polymer Ecomat Changchun 130022 Peoples R China Chinese Acad Sci Grad Sch Beijing 10080 Peoples R China NE Normal Univ Coll Life Sci Changchun 130024 Peoples R China

Biodegradable polymer blends based on biosourced polymers, namely polylactide (PLA) and poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P(3HB-co-4HB)), were prepared by melt compounding. The effects of P(3HB-co-4HB) on the miscibility, phase morphology, thermal behavior, mechanical properties, and biodegradability of PLA/P(3HB-co-4HB) blends were investigated. The blend was an immiscible system with the P(3HB-co-4HB) domains evenly dispersed in the PLA matrix. However, the Tg of P(3HB-co-4HB) component in the blends decreased compared with neat P(3HB-co-4HB), which might be attributed to that the presence of the phase interface between PLA and P(3HB-co-4HB) resulted in enhanced chain mobility near interface. The addition of P(3HB-co-4HB) enhanced the cold crystallization of PLA in the blends due to the nucleation enhancement of PLA caused by the enhanced chain mobility near the phase interface between PLA and P(3HB-co-4HB) in the immiscible blends. With the increase in P(3HB-co-4HB) content, the blends showed decreased tensile strength and modulus;however, the elongation at beak was increased significantly, indicating that the inherent brittlement of PLA was improved by adding P(3HB-co-4HB). The interesting aspect was that the biodegradability of PLA is significantly enhanced after blends preparation. POLYM. COMPOS., 2012. (C) 2012 Society of Plastics Engineers

关键词： programmable logic arrays Cold crystallization Polymer blends Beak Blends Polylactides biodegradability Phase interfaces

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Macroporous and nanometre scale fibrous PLA and PLA-HA composite scaffolds fabricated by a bio safe strategy

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RSC ADVANCES 2014年第106期4卷 61491-61502页

作者： Salerno, Aurelio Fernandez-Gutierrez, Mar Roman del Barrio, Julio San Domingo Pascual, Concepcion CSIC ICMAB Inst Mat Sci Barcelona Bellaterra 08193 Spain CSIC Inst Polymer Sci & Technol E-28006 Madrid Spain CIBER BBN Hlth Inst Carlos III Zaragoza Spain

The present study deals with the design, fabrication and characterization of porous scaffolds for tissue engineering made of polylactic acid (PLA) and PLA containing hydroxyapatite (HA) nanoparticles. The main novelty relies on the fact that the fabrication of the scaffolds has been achieved avoiding totally the use of toxic chemicals. In particular, the scaffolds are obtained by combining both thermal induced phase separation (TIPS) using ethyl lactate (EL) solutions and supercritical CO2 (scCO(2)) drying processes. Furthermore, gelatin particles have been used as a leachable porogen and combined with the previous processes to improve the control of the pore structure features of the scaffolds. The results show that the developed technique allows for the fabrication of porous PLA scaffolds with HA concentrations up to 30 wt%. Furthermore, these scaffolds are characterized by an overall porosity as high as 98% and a double scale pore structure. In particular, the appropriate control of the TIPS process and the scCO(2) drying allowed for the development of nanoscale fibrous PLA and PLA-HA structures starting from PLA/EL solutions. Concomitantly, the proper selection of the size range of gelatin particles as well as their spatial distribution in the mixture allowed imprinting an interconnected network of large pores inside the scaffolds.

关键词： programmable logic arrays fabrication Online resources THERMALLY INDUCED PHASE SEPARATION Structural properties Toxic chemicals Nanometers Porous size range Tissue Engineering Pore structure

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Water absorption and hygrothermal aging behavior of short ramie fiber-reinforced poly(lactic acid) composites

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POLYMER COMPOSITES 2018年第4期39卷 1098-1104页

作者： Yu, Tao Sun, Fei Lu, Minyu Li, Yan Tongji Univ Sch Aerosp Engn & Appl Mech 1239 Siping Rd Shanghai 200092 Peoples R China Fudan Univ State Key Lab Mol Engn Polymers Shanghai 200433 Peoples R China

Short ramie/poly(lactic acid) (PLA) composites were prepared by using extrusion and injection moulding method. The water absorption and hygrothermal aging behaviors of ramie/PLA composites at 60 degrees C was analyzed. The water absorption and mechanical properties of the ramie/PLA composites with immersion time were reported and compared to those of neat PLA. Crystallinity and molecular weight of neat PLA and ramie/PLA composites were determined by differential scanning calorimetry and gel permeation chromatography, respectively. The results showed that the water absorption and mechanical properties was affected by the short ramie fiber. Ramie/PLA composites showed higher saturation weight gains and diffusion coefficients than that of neat PLA, which indicated that the addition of short ramie fiber induced higher water absorption caused by the hydrophilic nature of the fibers. Tensile strength and flexural strength severely decreased after aging. Moreover, it was found that PLA was severely degraded in hygrothermal environment, and ramie accelerated the degradation of PLA. The morphologies of fractured surfaces of neat PLA and ramie/PLA composites with different immersion time were observed by scanning electronic microscopy. The micro-cracks and voids were found which was due to the degradation of PLA and debonding of ramie and PLA. POLYM. COMPOS., 39:1098-1104, 2018. (c) 2016 Society of Plastics Engineers

关键词： Boehmeria EXTRUSION INJECTION MOLDING RAMIE FIBER hygrothermal environment programmable logic arrays Composites ageing behavior

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THE USE OF CNN MODELS IN THE SUBCORTICAL VISUAL PATHWAY

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-FUNDAMENTAL THEORY AND APPLICATIONS 1993年第3期40卷 182-195页

作者： ROSKA, T HAMORI, J LABOS, E LOTZ, K ORZO, L TAKACS, J VENETIANER, PL VIDNYANSZKY, Z ZARANDY, A SEMMELWEIS SCH MED DEPT ANAT ISTH-1450 BUDAPESTHUNGARY

The CNN model is now a paradigm of cellular analog programmable multidimensional processor array with distributed local logic and memory. It has turned out that for biological sensory information processing this model is so natural that a lot of neuroanatomical structures can be directly translated into CNN models. In this paper first we show the equivalent notions of neuroanatomy and the CNN model, motivated by studying the visual system. Next, various, mainly subcortical phenomena are studied. Simple effects like directional sensitivity and length tuning are modeled. A more accurate retina model has been developed taking into account some effects of amacrine cells. It is shown that the standard errors occurring in simple models of retinal illusions can be eliminated by using our more accurate models including delays. LGN effects with and without cortical feedback are modeled as well. Their CNN models are simple. Furthermore, simple texture detection effects and motion illusions are explained by neuromorphic CNN models. Local connectivity within a finite neighborhood, equivalent templates of different receptive field organizations, delay-templates have proved to be key issues. The goal is to translate known effects into CNN models and to show a framework for further studies.

关键词： Cellular neural networks Biological system modeling programmable logic arrays Retina Delay Visual system Neuromorphics Multidimensional systems Turing machines Biosensors

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