检索结果-内蒙古大学图书馆

作者： Konrad, Johannes Rogge, Norbert Vasilyan, Suren Rothleitner, Christian Fröhlich, Thomas Physikalisch-Technische Bundesanstalt (PTB) Braunschweig 38116 Germany Institute of Process Measurement and Sensor Technology Technische Universität (TU) Ilmenau Ilmenau 98684 Germany

PTB's redesigned Planck-Balance – a compact variant of a Kibble balance – is used to investigate the effects of coil motion misalignment on the final measurement result at the 1·10⁻⁶ level. It shows that, at this level of precision, the measured mass value is not dependent on the movement direction of the coil for deviation angles smaller than 0.5° from the gravity vector g, as long as the displacement is measured parallel to g. The experiments have been carried out by tilting the weighing module of the Planck-Balance, which is separated from the displacement measurement module by design. As the moving mechanism – which realises an approximately linear and constrained coil motion – is the same for both modes of the experiment, this is expected, considering the associated mathematical calculations which have already been carried out. Due to the operational effort regarding alignment procedures necessary in most conventional Kibble balances, the reported result is an important step towards broader practical applications, simplifying the implementation of Kibble's principle. © 2024

关键词： Alignment Constrained motion Interferometer Kibble balance Kilogram Mass determination Planck-balance

来源：评论

学校读者我要写书评

暂无评论

Simulated bubble oscillations in gearboxes for electrified vehicles 14

Simulated bubble oscillations in gearboxes for electrified v...

引用

14th International Conference on Recent Advances in Structural Dynamics, RASD 2024

作者： Hafner, Lukas Holzbrecher, Jonas Wiedenmann, Matthias Hieronymus, Timm Schwarzer, Steffen Dohnal, Fadi Evamo - Pump Technology Solutions PS GmbH Berlin Germany Research Center for Microtechnology Vorarlberg University of Applied Sciences Dornbirn Austria Institute of Measurement and Sensor Technology UMIT TIROL - Private University for Health Sciences and Health Technology Hall in Tirol Austria Institute for Drive Technology Aalen University of Applied Sciences Aalen Germany

The shift in drive concepts from internal combustion engines to electrified vehicles is changing the demands on drive machines and their associated subsystems. A well-known phenomenon in oil-lubricated transmissions is the unavoidable mixing of air with the oil during operation. The so-called oil-air-dispersion that occurs can be measured on the basis of the air bubble size and air bubble size distribution in the oil in a dispersion spectrum that occurs depends on geometry, speed and torque. Due to the increase in speed by several orders of magnitude in electrified vehicles, the speed- and torque-based vibration excitation of the transmission changes both in the excitation frequencies and in the excitation amplitudes. This brings physical effects into focus that previously played no role in drive technology. One of these physical effects is vibration-induced cavitation, which generates high pressures and temperatures and has negative effects on both the oils used and the mechanical components. The vibration behavior of air bubbles in oil is calculated using the Gilmore model from a realistic bubble size and relevant excitation frequencies. © 2024 institute of Physics Publishing. All rights reserved.

关键词： Internal combustion engines

来源：评论

学校读者我要写书评

暂无评论

Calibration of the stiffness of soft cantilevers based on electromagnetic and electrostatic force compensation principles

Calibration of the stiffness of soft cantilevers based on el...

引用

作者： Cherkasova, Valeriya Li, Zhi Popadic, Radovan Froehlich, Thomas Brand, Uwe Institute of Process Measurement and Sensor Technology Technische Universität Ilmenau Ilmenau Germany Department 5.1 Surface Metrology Physikalisch-Technische Bundesanstalt PTB Braunschweig Germany

This article presents a modified version of a traceable force-displacement measurement device developed at TU Ilmenau. The calibration of forces is carried out by a balance with the electromagnetic and electrostatic principles of force compensation. As part of this study, the device was used to calibrate the stiffness of soft cantilevers. The expanded relative uncertainty of the measured stiffnesses in the range from 13 mN/m to 100 mN/m ranged from 1.5 % to 2.7 %. The device was also verified through two-way comparison of measurements with the PTB, good agreement was obtained. © 2024

关键词： Calibration Electromagnetic force compensation Electrostatic force compensation Nanoforces Soft cantilever

来源：评论

学校读者我要写书评

暂无评论

Loss-engineering of a bimodal waveguide interferometer: An optimized silicon nitride platform for chemical and biological sensing 13

Loss-engineering of a bimodal waveguide interferometer: An o...

引用

Optical Modeling and Performance Predictions XIII 2023

作者： Hörmann, Samuel M. Hinum-Wagner, Jakob W. Bergmann, Alexander ams-OSRAM AG Tobelbaderstraße 30 Premstaetten8141 Austria Institute of Electrical Measurement and Sensor Systems Graz University of Technology Inffeldgasse 33 Graz8010 Austria

ISBN: (纸本)9781510665422

Integrated photonic sensors are promising devices to detect the presence of biological and chemical substances. Especially, silicon photonics features scalable, compact, and robust applications in, inter alia, the medical, pharmaceutical, and chemical industries for decentralized, real-time sensing. In an effort to continuously lower the limit of detection and build ultra precise devices, their sensitivity is steadily increased. The optical loss, however, is often neglected. This reduces the available intensity in the transmission spectrum and, thus, restricts the achievable limit of detection. We optimize a bimodal waveguide interferometer for environmental sensing based on a silicon nitride platform. Thereby, we combine considerations regarding the sensitivity, optical loss, and coupling into a figure of merit to design the single-mode and the bimodal platforms. To that end, we utilize a recently developed model of surface-roughness-induced scattering to include the estimated propagation loss in the design process. This model uses the simulated modes and measured autocovariance in the surface roughness for an estimation of the propagation loss in the real platform. We observe that considering the optical loss favors platforms of medium height for a quasi-transverse-electric polarization. In consequence, we demonstrate drastic changes in the design choices compared to pure sensitivity-focused waveguide platforms. Thus, we show that a holistic design process is essential to fully utilize the potential of integrated photonic devices. Ultimately, we are convinced that this methodology will be beneficial in making integrated photonic sensors more sensitive. © 2023 SPIE.

关键词： Surface roughness

来源：评论

学校读者我要写书评

暂无评论

CART-based optimization of core and cladding layers in silicon nitride photonic integrated circuits towards propagation and bend loss minimization 4

CART-based optimization of core and cladding layers in silic...

引用

Emerging Applications in Silicon Photonics IV 2023

作者： Hinum-Wagner, Jakob Wilhelm Scheibelhofer, Peter Hörmann, Samuel Marko Schmidt, Christoph Feigl, Gandolf Kraft, Jochen Bergmann, Alexander Institute of Electrical Measurement and Sensor Systems Graz University of Technology Inffeldgasse 33 Graz8010 Austria Ams-OSRAM Ag Tobelbaderstra e 30 Premstaetten8141 Austria

ISBN: (纸本)9781510668416

In the burgeoning field of sensing, Photonic Integrated Circuits (PICs) are essential tools for precise, high-speed detection of biological markers and particles. The performance of these biosensors is intricately linked to the losses of PICs, which is largely determined by the configuration of their core and cladding layers. Recognizing this, the present study ventures into the optimization of these layers in Silicon Nitride (Si3N4) PICs, employing an innovative approach using Classification and Regression Trees (CART). The study identifies propagation and bend losses, two critical factors affecting PIC performance, as response variables. In contrast, the physical characteristics of the core and cladding layers are considered as input variables. To ensure the robustness and completeness of the study, an appropriate Design of Experiments (DOE) is implemented, meticulously exploring possible combinations of layer configurations. Following the DOE, the CART algorithm is then applied to this design space, whereas the losses act as response variables. The algorithm functions by partitioning the design space into regions associated with specific layer configurations and iteratively refines these partitions based on their corresponding impact on propagation and bend losses. The end results of this process is the statistical information about the layer stacks which come with significantly low propagation and bend losses, thereby enhancing PIC performance. This improvement in performance directly translates to heightened sensitivity and specificity in biosensors. Further, the application of the CART methodology has demonstrated its potential to streamline the PIC design process, enhancing its robustness, an aspect critical for practical implementation in fabrication environments. © 2023 SPIE.

关键词： Design of experiments

来源：评论

学校读者我要写书评

暂无评论

Integrated interferometer design for zero cross-sensitivity to matrix perturbations 26

Integrated interferometer design for zero cross-sensitivity ...

引用

Novel Optical Systems, Methods, and Applications XXVI 2023

作者： Hörmann, Samuel M. Hinum-Wagner, Jakob W. Bergmann, Alexander ams OSRAM Group Tobelbader Strasse 30 Premstaetten8141 Austria Institute of Electrical Measurement and Sensor Systems Graz University of Technology Inffeldgasse 33 Graz8010 Austria

ISBN: (纸本)9781510665446

Integrated photonic biosensors constitute an important technology for the growing point-of-care paradigm. Due to their high sensitivity and ample design freedom, interferometric sensors are an attractive embodiment for this application. In an effort to continuously lower the limit of detection and build ultra-precise devices, the sensitivity is steadily increased. Thereby, the limiting factors are optical loss, noise, and cross-sensitivities to external perturbations. We present a novel design method for integrated interferometers to inherently compensate for the cross-sensitivity to bulk perturbations in the matrix’s refractive index. We exploit that the analyte induces a localized effect when binding to the bioreceptors. By using different guided modes with engineered phase signals in the interferometer, we distinguish between analyte binding and bulk perturbations. To first order, their optical path may be designed such that the relative change due to bulk perturbations vanishes while sensitivity to the analyte is retained. We demonstrate this methodology via simulations of a Mach-Zehnder-interferometer for an immunosensor based on a silicon nitride platform. We show that this design may be easily incorporated in most conventional layouts, due to an excess of degrees of freedom, and could further be applied in fiber-based devices. In this manner, interferometers utilizing guided modes could compensate cross-talk for perturbations in the matrix’s temperature, pH, or general chemical composition. We believe that eliminating these limiting external impacts could help integrated photonic biosensors to overcome current issues with reliability and robustness. © 2023 SPIE.

关键词： Refractive index

来源：评论

学校读者我要写书评

暂无评论

State of Charge-Dependent Changes in Spectral Composition of Guided Lamb Waves in Lithium-Ion Batteries

State of Charge-Dependent Changes in Spectral Composition of...

引用

2023 IEEE International Ultrasonics Symposium, IUS 2023

作者： Swaschnig, Patrick Klambauer, Reinhard Kofler, Johannes Bergmann, Alexander Graz University of Technology Institute of Electrical Measurement and Sensor Systems Graz Austria Tdk Electronics GmbH & Co Og European R&d Center Deutschlandsberg Austria

ISBN: (纸本)9798350346459

This study investigates symmetrical Lamb wave behavior across varying state-of-charge levels in lithium-ion batteries. Utilizing piezoelectric transducers, the research focuses on inducing and detecting Lamb waves in lithium-ion batteries. The outcomes uncover correlations between Lamb wave characteristics and state-of-charge variations, revealing insights into the potential of Lamb waves as indicators of internal changes in battery structures. Furthermore, the influence of chemomechanical alterations within battery structures on Lamb wave properties is explored. The insights gained offer valuable implications for understanding battery performance dynamics and internal transformations. © 2023 IEEE.

关键词： Surface waves

来源：评论

学校读者我要写书评

暂无评论

Investigations on the tracking control and performance of a long stroke vertical nanopositioning drive 22

Investigations on the tracking control and performance of a ...

引用

22nd International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2022

作者： Huaman, Alex S. Gorges, Stephan Katzschmann, Michael Hesse, Steffen Fröhlich, Thomas Manske, Eberhard Ilmenau98693 Germany Institute of Process Measurement and Sensor Technology Technische Universität Ilmenau Ilmenau98693 Germany

ISBN: (纸本)9781998999118

This paper presents an approach to equip an existing planar nanoprecision drive system with specially designed lifting and actuating units (LAUs), which can lift several kilograms along a vertical stroke of 10 mm with nanometer precision. These modules contain a pneumatic actuator to counteract the weight force along the entire travel range without introducing significant heat into the measurement space. An additional parallel acting electromagnetic actuator provides the precision positioning forces. As an initial step toward a full 6D system, each LAU is set up individually on a test bench. Using an included laser interferometric measurement system and emulated loads, allows for the development and evaluation of different control strategies within the simulation framework and via real-time experiments. Designing a controller for a single LAU involves an in-depth research into its overactuated nature and the derivation of a detailed model of the drive as well as the motion system. The proposed control strategy achieves subnanometer precision by integrating a feedforward stage for trajectory tracking and an output-feedback stage for stabilization and disturbance rejection. In this context, the output-feedback controller highlights a composite state and disturbance observer. In order to accomplish an adequate tradeoff between performance and robustness, the controller tuning is performed in the time and frequency domain based on systematic LQR/LQG design methods. The effectiveness of the presented control strategy is verified via real-time experimentation, where the overall control scheme allows RMS positioning errors below 0.3 nm which seem to be dominated by the measurement noise. Moreover, it renders very low heat dissipation of about 54 nW to carry a 4 kg payload. © European Society for Precision Engineering and Nanotechnology, Conference Proceedings - 22nd International Conference and Exhibition, EUSPEN 2022. All rights reserved.

关键词： Nanotechnology

来源：评论

学校读者我要写书评

暂无评论

Range Revolved Interferometry for use in high precision positioning systems 39

Range Revolved Interferometry for use in high precision posi...

引用

39th Annual Meeting of the American Society for Precision Engineering, ASPE 2024

作者： Grabowski, Axel Mittag, Sven Walenda, Carolin Kissinger, Thomas SE & Co. KG Auf der Roemerstrasse 1 Karlsruhe76228 Germany Institute for Process Measurement and Sensor Technology Technical University of Ilmenau Gustav-Kirchhoff-Str. 1 Ilmenau98693 Germany

ISBN: (纸本)9781887706612

We presented here a new fiber-based interferometer technology in a functional sample usable for industrial applications. We have shown an evaluation of the basic properties like positional noise, linearity and stability over 64 hours of measuring time. The unique features of the data processing scheme enable the system to measure with very low periodic errors. Additionally, it has been proven that the detection of more than one surface is doable and even further, that it is capable of measuring and tracking the thickness of optical transparent systems. Furthermore, it is possible to use the system in cryogenic environments. This has been demonstrated by characterizing different piezoelectric materials in a temperature range between room temperature and 4K. The form factor of the sensor heads is very small, enabling the construction of very compact piezo stages. © 2024 Proceedings - ASPE 2024 Annual Meeting. All rights reserved.

关键词： Piezoelectric materials

来源：评论

学校读者我要写书评

暂无评论

Combination of pipette aspiration and OCT: A novel method for frequency-dependent elasticity assessment of silicone tissue phantoms

引用

measurement: sensors 2025年 38卷

作者： Lamprecht, Raphael Scheible, Florian Sutor, Alexander Institute of Measurement and Sensor Technology UMIT TIROL – Private University for Health Sciences and Health Technology Hall in Tirol Austria

Measuring the frequency-dependent material properties of soft tissues is a challenging task, but it is crucial to understanding their function. This work presents a novel setup that combines optical coherence tomography and dynamic pipette aspiration to simultaneously measure the dynamic Young's modulus and high-resolution optical coherence tomography images. The procedure applies a sinusoidal pressure fluctuation to silicone tissue phantoms of varying stiffness and analyses the optical coherence tomography images to determine the resulting displacement. The Young's modulus is calculated by normalizing the pressure and displacement data to the pipette radius. This approach accurately measures Young's modulus and reveals its frequency dependence. This novel technique paves the way for future investigations into microscale tissue mechanics and a deep analysis of the tissue properties. © 2024

关键词： Phantoms

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：