Investigation of a shotcrete accelerator for targeted control of material properties for 3D concrete printing injection method

On the porosity of low-clinker shotcrete and accelerated pastes

The role of ettringite seeds in enhancing the ultra-early age strength of Portland cement containing aluminum sulfate accelerator

In coastal water monitoring, abrupt pH changes might indicate different pollution sources. Existing sensors for pH monitoring in coastal waters at low cost are mainly based on a glass membrane and a reference electrode. Virtual sensors are elements capable of measuring certain parameters based on data from other parameters or variables. The aim of this paper is to propose the use of a virtual pH sensor based on measuring different physical effects of H+ on the electromagnetic field generated by an inductor. Double inductors based on two solenoids of 40 and 80 spires are used as sensing elements. Samples with pH from 4 to 11 are used, and the effect of temperature is evaluated using samples from 10 to 40 °C. The induced voltage and the delay of the signal are measured for powering frequencies from 100 to 500 kHz. These data of delay, induced voltage, frequency, and temperature are included in a probabilistic neural network to classify these data according to the pH. The results indicate low accuracy for samples with a pH of 11. A second analysis, excluding these data, offered correctly classified cases of 88.9%. The system can achieve considerable high accuracy (87.5%) using data gathered at a single frequency, from 246 to 248 kHz. The predicted versus observed data is correlated with a linear model characterized by an R2 of 0.69, which is similar to the ones observed in other virtual sensors.

/pdf/a-low-cost-virtual-sensor-for-underwater-ph-monitoring-in-1zr28mlk.pdf

A Low-Cost Virtual Sensor for Underwater pH Monitoring in Coastal Waters

Degradation of Prestressed GFRP Bars Embedded in Seawater–Sea Sand Geopolymer Mortars under Hydrothermal Seawater Aging

In situ pH monitoring in accelerated cement pastes

In this study the concept of using GBAS corrections and integrity parameters for UAV operations is explored. The GBAS messages are received and decoded at the airport to overcome the issue of VDB coverage for alternative applications that do not have line-of-sight to the GBAS. A flight test at a distance of about 15 km from an operational GBAS ground station was conducted using a quadrotor UAV as test vehicle. The recorded GBAS messages and recorded pseudoranges and carrier phases were subsequently used to evaluate the performance that can be obtained. One main issue that was identified is the number of satellites lost when maneuvering the drone. Loss of tracking requires a re-initialization of the smoothing filter and thus entails a wait time before a satellite can be used for positioning again. The GBAS corrections are generated based on 100 s smoothing, requiring a user to use the same smoothing time constant do avoid potential differential error buildups due to different filters. Hence, the time until a satellite can be used again after reacquisition may be substantial. When losing several satellites simultaneously or shortly after another this decreases the number of available satellites significantly and negatively impacts accuracy and protection level performance of this proposed mode of operation. The paper also studies the multipath effect at different altitudes and for different smoothing time constants compared to the standardized error models that were defined for large transport aircraft. When using 100 s smoothing the results indicate that the models are suitable also for the use case of UAV operations. 

Flight Testing GBAS for UAV Operations

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Patrick Steiner

Author Tools

Chat about Author

Papers

In situ pH monitoring in accelerated cement pastes

Flight Testing GBAS for UAV Operations