- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Approximate Circuits (Methodologies and CAD) || Approximate Computing for Iris Recognition Systems
摘要： For applications with tolerance for small degradation in the quality of results, approximate computing techniques have been successfully applied in both software and hardware design to cut down the system overhead. Many of the recent studies focus on high growth areas such as machine learning and computer vision. In this chapter, we introduce biometric security as another ideal target for the approximate computing techniques for reasons we shall discuss. Biometric security applications include but are not limited to ?nger printing, iris recognition, and face identi?cations. Two of the main reasons which make these applications ideal are: (1) the biometrics are data rich and can be compute intensive, and (2) the biometrics signatures of different individuals are large with statistical guarantee, and (3) the methods to obtain the biometric data are often noisy, which means the signature of the same individual can vary among different instances. As an example, the industry standards for iris as biometric identi?cation, e.g., ISO/IEC 19794-6, consider two iris encodings, each of which contains 2048 bits, as a positive match even if Hamming distance between the encoding and an ideal case encoding is 25%. This is due to the statistical guarantee that the false positive match rate is merely 1 in 13 billion for the irises of two different individual or even different eyes of the same individual to have a Hamming distance of less than 25% [1].
关键词： iris recognition,biometric security,SW/HW co-design,reinforcement learning,approximate computing
更新于2025-09-04 15:30:14
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[IEEE 2018 IEEE Photonics Conference (IPC) - Reston, VA, USA (2018.9.30-2018.10.4)] 2018 IEEE Photonics Conference (IPC) - Fabrication-Tolerant Efficient Dual-Etch Grating Couplers with Low Back Reflections
摘要： Using inverse electromagnetic design, we optimize dual-etch grating couplers with a 100 nm minimum feature size compatible with DUV lithography that achieve a record peak coupling efficiency of ?0.7 dB and unprecedented low back reflection of < ?40 dB.
关键词： back reflection,coupling efficiency,dual-etch grating couplers,DUV lithography,inverse electromagnetic design
更新于2025-09-04 15:30:14
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Optimization of photocatalytic degradation of dye?wastewater?by CuFe<sub>2</sub>O<sub>4</sub>/AgBr composite using response surface methodology
摘要： In this paper, a simple response surface methodology (RSM) based on central composite design (CCD) was applied to determine the optimum processing parameters of photocatalytic degradation of acid red 88 (AR88) by CuFe2O4/AgBr composites. The effect of CuFe2O4 loading, initial concentration of pollutant, and photocatalyst concentration on the yield of AR88 degradation rate was investigated. Based on the statistical experimental design, the maximum degradation rate of 94.7% was achieved under optimal conditions: the 34.69% of CuFe2O4 loading, 16.34mg/L of intial concentration of AR88, 1.51g/L of photocatalyst concentration. The kinetics exploration indicated that the degradation process fitted pseudo-first order kinetic model. What’t more, the trapping experiment of active species demonstrated that ·O2- and ·OH were the dominant species.
关键词： CuFe2O4/AgBr composites,response surface methodology,central composite design,acid red 88,photocatalysis
更新于2025-09-04 15:30:14
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[IEEE 2018 IEEE Energy Conversion Congress and Exposition (ECCE) - Portland, OR, USA (2018.9.23-2018.9.27)] 2018 IEEE Energy Conversion Congress and Exposition (ECCE) - Grid Power-Smoothing Performance Improvement for PV and Electric Vehicle (EV) Systems
摘要： The integration of PVs and EVs is considered a possible route to achieving actual zero-emissions. Moreover, EVs can be used as energy storage resources to address the intermittent nature of PVs. This paper investigates the peak-shaving and power-smoothing capabilities for PV-EV integrated systems. First, a PV-EV system is detailed and the uncertainty factors are presented. Then, a peak-shaving algorithm is proposed and the grid’s peak-shaving and power-smoothing performance for different scenarios is presented. Poor performance in cases of home charging is described and an improvement by using immobile battery packs is proposed to further smooth the power fluctuation. The quantitative minimum sizing (including power and energy) for the battery packs is detailed. Finally, simulation results are provided to validate the proposed algorithm.
关键词： battery design,peak-shaving,power-smoothing,PV-EV
更新于2025-09-04 15:30:14
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[IEEE 2018 IEEE Energy Conversion Congress and Exposition (ECCE) - Portland, OR, USA (2018.9.23-2018.9.27)] 2018 IEEE Energy Conversion Congress and Exposition (ECCE) - Low-Cost High-Efficiency Single-Stage Solid-State Transformer for Lighting Applications
摘要： This paper presents a low-cost high-efficiency single-stage 480 Vrms to 264 Vrms solid-state transformer (SST) for lighting applications. The proposed SST is based on center-point-clamped (CPC) ac-ac buck converter topology. A comprehensive cost and efficiency optimization methodology is developed to help identify the most appropriate SST design across a design space comprising various switch structures, a range of operating frequencies, and different inductance values. For the selected implementation, a novel switching scheme is introduced that ensures smooth inductor current commutation during switching transitions, and also reduces zero-crossing distortion in the input current. Furthermore, an active voltage balancing scheme is developed to compensate for any imbalances between the two stacked input capacitors to ensure robust converter operation. A prototype 600-W solid-state transformer based on the proposed optimization, designed to operate at an input voltage of 480 Vrms and an output voltage of 264 Vrms is built and tested. The prototyped converter achieves a peak efficiency of 96%, maintains an efficiency of above 92% across a 3:1 output power range, and has a power density of 40 W/in3.
关键词： efficiency optimization,center-point-clamped converter,low cost converter design,ac-ac converter,active voltage balancing,cost optimization
更新于2025-09-04 15:30:14
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A molecular design strategy to construct the near-infrared fluorescent probe for selectively sensing human cytochrome P450 2J2
摘要： Cytochrome P450 2J2 (CYP2J2), a key enzyme responsible for oxidative metabolism of various xenobiotics and endogenous compounds, participates in a diverse array of physiological and pathological processes in humans. Its biological role in tumorigenesis and cancer diagnosis remains poorly understood, owing to the lack of molecular tools suitable for real-time monitoring CYP2J2 in complex biological systems. Using molecular design principles we were able to modify the distance between the catalytic unit and metabolic recognition moiety, allowing us to develop a CYP2J2 selective fluorescent probe using a near-infrared fluorophore (E)-2-(2-(6-hydroxy-2, 3-dihydro-1H-xanthen-4-yl)vinyl)-3,3-dimethyl-1-propyl-3H-indol-1-ium iodide (HXPI). To improve the reactivity and isoform specificity, a self-immolative linker was introduced to the HXPI derivatives in order to better fit the narrow substrate channel of CYP2J2, the modification effectively shortened the spatial distance between the metabolic moiety (O-alkyl group) and catalytic center of CYP2J2. After screening a panel of O-alkylated HXPI derivatives, BnXPI displayed the best combination of specificity, sensitivity and applicability for detecting CYP2J2 in vitro and in vivo. Upon O-demethylation by CYP2J2, a self-immolative reaction occurred spontaneously via 1,6-elimination of p-hydroxybenzyl resulting in the release of HXPI. Allowing BnXPI to be successfully used to monitor CYP2J2 activity in real-time for various living systems including cells, tumor tissues, and tumor-bearing animals. In summary, our practical strategy could help the development of a highly specific and broadly applicable tool for monitoring CYP2J2, which offers great promise for exploring the biological functions of CYP2J2 in tumorigenesis.
关键词： Cytochrome P450 2J2,near-infrared fluorescent probe,real-time monitoring,molecular design,CYP2J2,tumorigenesis
更新于2025-09-04 15:30:14
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[IEEE 2018 20th International Conference on Transparent Optical Networks (ICTON) - Bucharest (2018.7.1-2018.7.5)] 2018 20th International Conference on Transparent Optical Networks (ICTON) - Recent Advances in 3D Structured Illumination Microscopy
摘要： In structured illumination microscopy (SIM) the sample under investigation is illuminated using a structured illumination (SI) pattern. This SI pattern encodes high spatial frequencies of fine features within the sample, which usually are not transferred by the conventional three-dimensional (3D) optical transfer function (OTF) of the imaging system and fills the missing cone of frequencies in the OTF for better discrimination of the out-of- focus light. Thereby, SIM provides super-resolution (SR) performance beyond the diffraction limit and optical- sectioning (OS) capability with the use of data post-processing approaches. 3D structured patterns that include lateral and axial variations in the illumination have attracted more attention recently as they provide OS and SR enhancement in three dimensions. In this paper, we review recent implementations in generating a 3D SI pattern with tunable modulation frequency (independently of both the objective lens and the wavelength used) using a Fresnel biprism or a Wollaston prism. From the raw SIM images, final SIM images with simultaneous OS and SR are retrieved without artifacts due to coherent noise.
关键词： Fresnel biprism,Wollaston prism,structured illumination design,super-resolution,tunable frequency,three-dimensional microscopy
更新于2025-09-04 15:30:14
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Analysis and Design of High Frequency 1-D CMUT Imaging Arrays in Non-collapsed Mode
摘要： High frequency ultrasound imaging arrays are important for a broad range of applications, from small animal imaging to photoacoustics. CMUT arrays are particularly attractive for these applications as low noise receiver electronics can be integrated for an overall improved performance. In this paper we present a comprehensive analysis of high frequency CMUT arrays based on an experimentally verified CMUT array simulation tool. The results obtained on an example, a 40 MHz 1-D CMUT array for intravascular imaging, are used to obtain key design insights and tradeoffs for receive only and pulse-echo imaging. For the receiver side, thermal mechanical current noise, plane wave pressure sensitivity, and pressure noise spectrum are extracted from simulations. Using these parameters, we find that the receiver performance of CMUT arrays can be close to an ideal piston, independent of gap thickness and applied DC bias, when coupled to low noise electronics with arrays utilizing smaller membranes performing better. For pulse-echo imaging, thermal mechanical current noise limited SNR is observed to be dependent on the maximum available voltage and gap thickness. In terms of bandwidth, we find that Bragg resonance of the array, related to the fill factor, is a significant determinant of the high frequency limit and the fluid loaded single membrane resonance determines the lower limit. Based on these results, we present design guidelines requiring only fluid loaded single membrane simulations and membrane pitch to achieve a desired pulse-echo response. We also provide a design example and discuss limitations of the approach.
关键词： CMUT,Bragg’s resonance,CMUT design,High frequency arrays,Phased array,Photoacoustic receiver
更新于2025-09-04 15:30:14
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[ACM Press The 31st Annual ACM Symposium - Berlin, Germany (2018.10.14-2018.10.14)] The 31st Annual ACM Symposium on User Interface Software and Technology - UIST '18 - Assembly-aware Design of Printable Electromechanical Devices
摘要： From smart toys and household appliances to personal robots, electromechanical devices play an increasingly important role in our daily lives. Rather than relying on gadgets that are mass-produced, our goal is to enable casual users to custom-design such devices based on their own needs and preferences. To this end, we present a computational design system that leverages the power of digital fabrication and the emergence of affordable electronics such as sensors and microcontrollers. The input to our system consists of a 3D representation of the desired device’s shape, and a set of user-preferred off-the-shelf components. Based on this input, our method generates an optimized, 3D printable enclosure that can house the required components. To create these designs automatically, we formalize a new spatio-temporal model that captures the entire assembly process, including the placement of the components within the device, mounting structures and attachment strategies, the order in which components must be inserted, and collision-free assembly paths. Using this model as a technical core, we then leverage engineering design guidelines and efficient numerical techniques to optimize device designs. In a user study, which also highlights the challenges of designing such devices, we find our system to be effective in reducing the entry barriers faced by casual users in creating such devices. We further demonstrate the versatility of our approach by designing and fabricating three devices with diverse functionalities.
关键词： Digital Fabrication,Optimization,Computational Design
更新于2025-09-04 15:30:14
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[IEEE 2017 International Conference on Optical Network Design and Modeling (ONDM) - Budapest (2017.5.15-2017.5.18)] 2017 International Conference on Optical Network Design and Modeling (ONDM) - Optical networking interconnecting disaggregated compute resources: An enabler of the 5G vision
摘要： This paper focuses on converged optical-wireless 5G infrastructures and proposes the novel concept of “Dis-Aggregated RAN” (DA-RAN) as an alternative to the RAN and C-RAN solutions. DA-RAN adopts the concept of “disaggregation” of hardware and software components across the wireless, optical and compute/storage domains. The performance of the proposed approach is evaluated through a service provisioning model that takes into consideration both the description of the heterogeneous 5G network and the processor details within the BBUs. Modeling results show significant benefits in terms of power consumption that range between 10-50%
关键词： resource disaggregation,converged optical-wireless infrastructures,optimal functional split,5G network design
更新于2025-09-04 15:30:14