Terrain modeling and path selection by an autonomous Martian exploratory vehicle

Computerized simulation of terrain sensing and modeling for unmanned surface vehicle on Mars surfac

Assessment of an in vitro whole cigarette smoke exposure system: The Borgwaldt RM20S 8-syringe smoking machine

<p>Abstract</p> <p>Background</p> <p>There have been many recent developments of <it>in vitro </it>cigarette smoke systems closely replicating <it>in vivo </it>exposures. The Borgwaldt RM20S smoking machine (RM20S) enables the serial dilution and delivery of cigarette smoke to exposure chambers for <it>in vitro </it>analyses. In this study we have demonstrated reliability and robustness testing of the RM20S in delivering smoke to <it>in vitro </it>cultures using an in-house designed whole smoke exposure chamber.</p> <p>Results</p> <p>The syringe precision and accuracy of smoke dose generated by the RM20S was assessed using a methane gas standard and resulted in a repeatability error of ≤9%. Differential electrical mobility particle spectrometry (DMS) measured smoke particles generated from reference 3R4F cigarettes at points along the RM20S. 53% ± 5.9% of particles by mass reached the chamber, the remainder deposited in the syringe or connecting tubing and ~16% deposited in the chamber. Spectrofluorometric quantification of particle deposition within chambers indicated a positive correlation between smoke concentration and particle deposition. <it>In vitro </it>air-liquid interface (ALI) cultures (H292 lung epithelial cells), exposed to whole smoke (1:60 dilution (smoke:air, equivalent to ~5 μg/cm²)) demonstrated uniform smoke delivery within the chamber.</p> <p>Conclusions</p> <p>These results suggest this smoke exposure system is a reliable and repeatable method of generating and exposing ALI <it>in vitro </it>cultures to cigarette smoke. This system will enable the evaluation of future tobacco products and individual components of cigarette smoke and may be used as an alternative <it>in vitro </it>tool for evaluating other aerosols and gaseous mixtures such as air pollutants, inhaled pharmaceuticals and cosmetics.</p

Status report on emerging photovoltaics

\ua9 2023 Society of Photo-Optical Instrumentation Engineers (SPIE).This report provides a snapshot of emerging photovoltaic (PV) technologies. It consists of concise contributions from experts in a wide range of fields including silicon, thin film, III-V, perovskite, organic, and dye-sensitized PVs. Strategies for exceeding the detailed balance limit and for light managing are presented, followed by a section detailing key applications and commercialization pathways. A section on sustainability then discusses the need for minimization of the environmental footprint in PV manufacturing and recycling. The report concludes with a perspective based on broad survey questions presented to the contributing authors regarding the needs and future evolution of PV

NRC photometer design for the realization of a luminous intensity scale

NRC publication: Ye

A Spectrum Injection-Based Approach for Malware Prevention in UHF RFID Systems

Radio frequency identification (RFID) is a technology that uses electromagnetic waves (EMW) to send, process, and store data by using a built-in integrated circuit and antenna. However, its susceptibility to malware attacks poses a threat to data privacy and system performance. Thus, there is a need to develop techniques to protect RFID systems from malware injection and improve efficiency through spectrum optimization. An approach for improving the efficiency and data privacy of RFID systems operating in the ultra-high frequency (UHF) band is proposed for multiple data rates of 160, 256, 320, and 640 kbps. Firstly, a method is introduced for reconstructing regular data in a malware-free RFID system with optimized spectrum usage, which reaches up to 50&#x0025; of the total spectrum and improves efficiency. Secondly, a spectrum injection-based approach (SIBA) is proposed by incorporating a bandpass filtering (BPF) technique to inject the missing spectrum of regular data with a portion of the malware-injected data spectrum. This approach results in faster and more precise data reconstruction with higher accuracy and overcomes the malware. A noise reduction technique based on BPF is also proposed to reduce the noise effects and enhance the accuracy of data reconstruction at different signal-to-noise ratio (SNR) levels. This technique is evaluated through extensive analysis with various metrics such as reconstruction accuracy, robustness to noise, bandwidth utilization factor (BUF), and computational complexity, making it suitable for resource-constrained environmental settings. These approaches address the challenges of malware injection and spectrum optimization, resulting in more efficient and secure RFID systems

Strategies In Learning Fluid Mechanics: A literature Review

One of the broad and intricate subfields of physics is fluid mechanics. Learning techniques for students are an essential component of learning fluid mechanics because they increase their motivation to learn, enhance learning outcomes, and encourage active participation in class. An overview of the prior research was highlighted in this publication, and several fluid mechanics learning methodologies were looked at in this review. The study found that the majority of students performed well in group settings, particularly when fluid mechanics principles are used in practical settings, which is the most successful teaching method. The studies that were reviewed in this literature review demonstrated that offering students team-based experiential learning is the best way to inspire them to learn fluid mechanics and to recognize the value of doing so. Therefore, by developing ideas and putting them into practice through active exploration, students learn more