scholarly journals Improving the precision of optical metrology by detecting fewer photons with biased weak measurement

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Peng Yin ◽  
Wen-Hao Zhang ◽  
Liang Xu ◽  
Ze-Gang Liu ◽  
Wei-Feng Zhuang ◽  
...  
Keyword(s):  
Optical Measurement ◽  
Low Cost ◽  
Photon Number ◽  
Weak Measurement ◽  
Saturation Effect ◽  
Optical Metrology ◽  
Detector Response ◽  
Improve Measurement ◽  
Measurement Protocol ◽  
Order Of Magnitude

AbstractIn optical metrological protocols to measure physical quantities, it is, in principle, always beneficial to increase photon number n to improve measurement precision. However, practical constraints prevent the arbitrary increase of n due to the imperfections of a practical detector, especially when the detector response is dominated by the saturation effect. In this work, we show that a modified weak measurement protocol, namely, biased weak measurement significantly improves the precision of optical metrology in the presence of saturation effect. This method detects an ultra-small fraction of photons while maintains a considerable amount of metrological information. The biased pre-coupling leads to an additional reduction of photons in the post-selection and generates an extinction point in the spectrum distribution, which is extremely sensitive to the estimated parameter and difficult to be saturated. Therefore, the Fisher information can be persistently enhanced by increasing the photon number. In our magnetic-sensing experiment, biased weak measurement achieves precision approximately one order of magnitude better than those of previously used methods. The proposed method can be applied in various optical measurement schemes to remarkably mitigate the detector saturation effect with low-cost apparatuses.

scholarly journals Improving GNSS Landslide Monitoring with the Use of Low-Cost MEMS Accelerometers

2019 ◽  
Vol 9 (23) ◽  
pp. 5075 ◽  
Author(s):  
Alberto Cina ◽  
Ambrogio Maria Manzino ◽  
Iosif Horea Bendea
Keyword(s):  
Low Cost ◽  
Calibration Procedure ◽  
Deformation Monitoring ◽  
Landslide Monitoring ◽  
Improve Measurement ◽  
Mems Accelerometers ◽  
Order Of Magnitude ◽  
Independent Technique ◽  
Important Basis ◽  
Interesting Alternative

Observation and monitoring of landslides and infrastructure is a very important basis for land planning, human activities, and safety. Geomatic techniques for deformation monitoring have usually involved GNSS and total station measurements or, more generally, expensive geodetic instruments, but other techniques, such as SAR (Synthetic Aperture Radar), can be efficiently applied. Using low-cost sensors could be an interesting alternative solution if the accuracy requirements can be satisfied. This paper shows the results obtained for tilt measurements using MEMS accelerometers, which were combined with mass-market GNSS sensors for monitoring five sites located on landslides. The use of a MEMS-like inclinometer requires an important calibration process to remove bias and improve the solution’s accuracy. In this paper, we explain the MEMS calibration procedure employed, with a simple and cheap solution. The results indicate that with a simple calibration, it is possible to improve measurement accuracy by one order of magnitude, reaching an angular accuracy of a few hundredths of a degree, verified by an independent technique.

scholarly journals CrossGR

2021 ◽  
Vol 5 (1) ◽  
pp. 1-23
Author(s):  
Xinyi Li ◽  
Liqiong Chang ◽  
Fangfang Song ◽  
Ju Wang ◽  
Xiaojiang Chen ◽  
...  
Keyword(s):  
Gesture Recognition ◽  
Low Cost ◽  
User Involvement ◽  
Recognition System ◽  
Training Data ◽  
Generative Adversarial Network ◽  
Adversarial Network ◽  
Target User ◽  
Order Of Magnitude ◽  
Training Examples

This paper focuses on a fundamental question in Wi-Fi-based gesture recognition: "Can we use the knowledge learned from some users to perform gesture recognition for others?". This problem is also known as cross-target recognition. It arises in many practical deployments of Wi-Fi-based gesture recognition where it is prohibitively expensive to collect training data from every single user. We present CrossGR, a low-cost cross-target gesture recognition system. As a departure from existing approaches, CrossGR does not require prior knowledge (such as who is currently performing a gesture) of the target user. Instead, CrossGR employs a deep neural network to extract user-agnostic but gesture-related Wi-Fi signal characteristics to perform gesture recognition. To provide sufficient training data to build an effective deep learning model, CrossGR employs a generative adversarial network to automatically generate many synthetic training data from a small set of real-world examples collected from a small number of users. Such a strategy allows CrossGR to minimize the user involvement and the associated cost in collecting training examples for building an accurate gesture recognition system. We evaluate CrossGR by applying it to perform gesture recognition across 10 users and 15 gestures. Experimental results show that CrossGR achieves an accuracy of over 82.6% (up to 99.75%). We demonstrate that CrossGR delivers comparable recognition accuracy, but uses an order of magnitude less training samples collected from the end-users when compared to state-of-the-art recognition systems.

scholarly journals Silicon Photonic Micro-Transceivers for Beyond 5G Environments

2021 ◽  
Vol 11 (22) ◽  
pp. 10955
Author(s):  
Kazuhiko Kurata ◽  
Luca Giorgi ◽  
Fabio Cavaliere ◽  
Liam O’Faolain ◽  
Sebastian A. Schulz ◽  
...  
Keyword(s):  
Quantum Dot ◽  
High Temperatures ◽  
Low Cost ◽  
Laser System ◽  
Data Rate ◽  
Ambient Temperatures ◽  
Quantum Dot Laser ◽  
Silicon Photonic ◽  
Order Of Magnitude ◽  
And Performance

Here, we report on the design and performance of a silicon photonic micro-transceiver required to operate in 5G and 6G environments at high ambient temperatures above 105 °C. The four-channel “IOCore” micro-transceiver incorporates a 1310 nm quantum dot laser system and operates at a data rate of 25 Gbps and higher. The 5 × 5 mm micro-transceiver chip benefits from a multimode coupling interface for low-cost assembly and robust connectivity at high temperatures as well as an optical redundancy scheme, which increases reliability by over an order of magnitude.

scholarly journals An uncertainty-based protocol for the setup and measurement of soot/black carbon emissions from gas flares using sky-LOSA

2020 ◽  
Author(s):  
Bradley M. Conrad ◽  
Matthew R. Johnson
Keyword(s):  
Open Source ◽  
Black Carbon ◽  
Open Source Software ◽  
Carbon Emissions ◽  
Climate Models ◽  
Optical Measurement ◽  
Measurement Data ◽  
Software Tool ◽  
Measurement Protocol ◽  
Measurement Uncertainties

Abstract. Gas flaring is an important source of atmospheric soot/black carbon, especially in sensitive Arctic regions. However, emissions have traditionally been challenging to measure and remain poorly characterized, confounding international reporting requirements and adding uncertainty to climate models. The sky-LOSA optical measurement technique has emerged as a powerful means to quantify flare black carbon emissions in the field, but broader adoption has been hampered by the complexity of its deployment, where decisions during setup in the field can have profound, non-linear impacts on achievable measurement uncertainties. To address this challenge, this paper presents a prescriptive measurement protocol and associated open-source software tool that simplifies acquisition of sky-LOSA data in the field. Leveraging a comprehensive Monte Carlo-based General Uncertainty Analysis (GUA) to predict measurement uncertainties over the entire breadth of possible measurement conditions, general heuristics are identified to guide a sky-LOSA user toward optimal data collection. These are further extended in the open-source software utility, SetupSkyLOSA, which interprets the GUA results to provide detailed guidance for any specific combination of location, date/time, and flare, plume, and ambient conditions. Finally, a case study of a sky-LOSA measurement at an oil and gas facility in Mexico is used to demonstrate the utility of the software tool, where potentially small region(s) of optimal instrument setup are easily and quickly identified. It is hoped that this work will help increase the accessibility of the sky-LOSA technique and ultimately the availability of field measurement data for flare black carbon emissions.

Liquid Chromatographic Determination of Benzoyl Peroxide in Acne Preparations

1984 ◽  
Vol 67 (5) ◽  
pp. 913-915
Author(s):  
Chih-Kuang Chou ◽  
David C Locke
Keyword(s):  
Benzoyl Peroxide ◽  
Limit Of Detection ◽  
Chromatographic Determination ◽  
Detector Response ◽  
Electrochemical Detector ◽  
Reverse Phase ◽  
Order Of Magnitude ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract A rapid, precise, and accurate liquid chromatographic (LC) method is described for the determination of benzoyl peroxide (BP) in acne preparations. BP is extracted from a water dispersion of the preparation with dichloromethane (DCM), and an aliquot is eluted from a C-18 reverse phase LC column with acetonitrile-O.lOM aqueous NaCI04. Selective and sensitive quantitation is accomplished with a reductive mode electrochemical detector. This detector is an order of magnitude more sensitive than a 240 nm UV absorption detector; the lower limit of detection is 2 ng for a 4 μL injection. The recovery of BP is 99.4% and the detector response is linear to at least 2 μg per 4 μL injection.

scholarly journals Imprinted plasmonic measuring nanocylinders for nanoscale volumes of materials

Nanophotonics ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 167-176 ◽  
Author(s):  
Jinfeng Zhu ◽  
Xizhao Chen ◽  
Yinong Xie ◽  
Jun-Yu Ou ◽  
Huanyang Chen ◽  
...  
Keyword(s):  
Analytical Chemistry ◽  
Visible Light ◽  
Optical Measurement ◽  
Low Cost ◽  
Soft Materials ◽  
Volume Changes ◽  
Fast Measurement ◽  
Biomedical Sensing ◽  
Material Volume ◽  
Non Destructive

AbstractOptical measurement of materials at the nanoscale is important for nanotechnology. Various plasmonic nanorulers have been studied for measuring nanoscale distance and orientation of materials, but they lack the capability to contain and measure nanoscale volumes, especially for liquid or soft materials. Here, we demonstrate the use of imprinted plasmonic volumetric nanocylinders, which act as nanoscale graduated cylinders and facilitate nanomaterial measurement via visible light. Our theoretical and experimental achievements illuminate a promising method for non-destructive, low-cost and fast measurement of material volume changes at the nanoscale, which will benefit the fields of analytical chemistry, nanofabrication and biomedical sensing.

Study on CMP Test Technology of 65 nm and below Node Wafers with Copper Interconnects

2012 ◽  
Vol 159 ◽  
pp. 297-301
Author(s):  
Ru Wang ◽  
Guo Feng Pan ◽  
Juan Wang ◽  
Rui Xia Yang ◽  
Yu Ling Liu
Keyword(s):  
Optical Measurement ◽  
Ph Value ◽  
Low Cost ◽  
Chelating Agent ◽  
Critical Dimension ◽  
Copper Interconnects ◽  
Current Feedback ◽  
Transmission Electron ◽  
Testing Technology ◽  
Point Detection

It is of significance to research high-removal efficiency and low-cost CMP process for the 65 nm and below node. Chemical mechanical polishing (CMP) can realize the planarization of the wafer with free defects, free contamination and below nanometer level roughness. Test project of CMP slurry is main contain of these detections such as pH value, chelating agent content, SiO2 gel particle size, ζ-potential detection and the observation by Transmission electron microscopy (TEM). End point detection method of pattern wafer CMP usually includes the non destructive optical measurement, motor current feedback measurement and polishing pad temperature test. The main problems of the measurement for pattern wafer CMP are critical dimension (CD), section, film thickness, defects and particles measurement. Some of the new type of testing technology, such as atomic force profiler (AFP), can be used to compare CMP effect, such as dishing, erosion, tungsten plugs, the height of steps and flatness of the wafer, which is significant for wafer CMP research.

Multi-Fidelity Physics-Constrained Neural Network and Its Application in Materials Modeling

2019 ◽  
Vol 141 (12) ◽  
Author(s):  
Dehao Liu ◽  
Yan Wang
Keyword(s):  
Neural Network ◽  
Neural Networks ◽  
Numerical Solutions ◽  
Low Cost ◽  
Training Data ◽  
Physical Constraints ◽  
Physical Knowledge ◽  
Materials Modeling ◽  
Order Of Magnitude ◽  
The Difference

Abstract Training machine learning tools such as neural networks require the availability of sizable data, which can be difficult for engineering and scientific applications where experiments or simulations are expensive. In this work, a novel multi-fidelity physics-constrained neural network is proposed to reduce the required amount of training data, where physical knowledge is applied to constrain neural networks, and multi-fidelity networks are constructed to improve training efficiency. A low-cost low-fidelity physics-constrained neural network is used as the baseline model, whereas a limited amount of data from a high-fidelity physics-constrained neural network is used to train a second neural network to predict the difference between the two models. The proposed framework is demonstrated with two-dimensional heat transfer, phase transition, and dendritic growth problems, which are fundamental in materials modeling. Physics is described by partial differential equations. With the same set of training data, the prediction error of physics-constrained neural network can be one order of magnitude lower than that of the classical artificial neural network without physical constraints. The accuracy of the prediction is comparable to those from direct numerical solutions of equations.

Design and Calibration of MIMU Based on Chip Size Micro Inertial Sensors

2013 ◽  
Vol 849 ◽  
pp. 302-309
Author(s):  
Yun Xu ◽  
Xin Hua Zhu ◽  
Yu Wang
Keyword(s):  
High Performance ◽  
Inertial Sensors ◽  
Low Cost ◽  
Rapid Development ◽  
Experimental Result ◽  
Integrated Navigation ◽  
Bias Stability ◽  
Chip Size ◽  
Order Of Magnitude ◽  
On Chip

With rapid development of micro fabrication technology, the performance of MIMU has gradually improved. The MIMU introduced in this paper is based on the silicon micro machined gyroscope of type MSG7000D and accelerometer of type MSA6000. The volume of it is 3×3×3cm3, the mass is 68.5g and the power consumption is less than 1w. The experimental result shows that the bias stability of the gyroscope and accelerometer for each axis of the designed MIMU is less than 10°/h and 0.5mg respectively. For the non orthogonality in three axes of the structure, MIMU needs to be calibrated. After calibration, the measurement accuracy has improved by an order of magnitude. The designed MIMU can satisfy the requirement of high performance, low cost, light weight and small size for strap-down navigation system, thus it can be widely applied not only to the field of vehicles integrated navigation, attitude measurement but also to the fields of personal goods such as mobile, game consoles and so on.

scholarly journals Monte Carlo simulation for the prediction of precision of absorbance measurements with a miniature CCD spectrometer

2003 ◽  
Vol 25 (2) ◽  
pp. 35-42 ◽  
Author(s):  
E. P. Tsaousoglou ◽  
S. D. Bolis ◽  
C. E. Efstathiou
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Light Intensity ◽  
Wavelength Range ◽  
Low Cost ◽  
Intrinsic Noise ◽  
Array Detector ◽  
Detector Response ◽  
Contour Plots ◽  
Data Acquisition Program

The precision characteristics of the absorbance measurements obtained with a low-cost miniature spectrometer incorporating an array detector were evaluated. Uncertainties in absorbance measurements were due to a combination of non-uniform light intensity and detector response over the wavelength range examined (350-850 nm), in conjunction with the digitization of the intensity indications and the intrinsic noise of the detecting elements. The precision characteristics are presented as contour plots displaying the expected RSD% of absorbances on the absorbance versus wavelength plane. The minimum RSD% for the spectrometer configuration tested was observed within the 0.2-1.5 absorbance units and 500-750 nm wavelength range. Without invoking signal enhancement features of the data-acquisition program (scan average, higher integration times, smoothing based on averaging the signal detected by adjacent pixels), the attainable precision within this range was 0.4-0.8%. A computer program based on Monte Carlo simulations was developed for the prediction of absorbance precision characteristics under various conditions of measurements.

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