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1. Comparing in-situ and ex-situ stress measurements in polymineralic rocks

   Goddard, Rellie; Hansen, Lars N.; Wallis, David; Stipp, Michael; Holyoke, Caleb W.; Kohlstedt, David L.; Goldsby, David L.; Durham, William B.; Kumamoto, Kathryn M.; Thom, Christopher (December 2018, American Geophysical Union Fall Meeting)

   Constraints on the state of stress in the lithosphere are fundamental to understanding a breadth of geological phenomena. Paleo-stresses are generally estimated using microstructural elements for which there are experimentally calibrated relationships with applied stress, with an emphasis on recrystallised grain-size piezometers. However, it is often difficult to clearly distinguish newly recrystallised grains from the relict matrix. Furthermore, these grain-size piezometers are only applicable to rocks consisting of a single mineral. An alternative proxy for paleo-stress in polymineralic rocks is the average subgrain size. Unfortunately, estimates of subgrain size differ significantly among different measurement methods, and therefore, piezometers must be individually calibrated for the method used. Existing subgrain-size piezometers are based on calibrations using optical or transmission electron microscopy. We use electron backscatter diffraction (EBSD), a common method of subgrain-boundary characterisation, to calibrate subgrain-size piezometers for both olivine and quartz. To test the application of our olivine subgrain-size piezometer to polymineralic rocks, we deformed synthetic mixtures of olivine and orthopyroxene. Experiments were conducted using a Deformation-DIA apparatus at beamline 6BM-B Advanced Photon Source, Argonne National Laboratory. These experiments offer the unique possibility of simultaneously deforming the sample and measuring the average stresses within each phase using X-ray diffraction, before applying subgrain-size piezometry to the recovered samples. The results provide tests of (1) the manner in which stress is partitioned between phases, (2) whether the stresses measured in each phase by X-ray diffraction are comparable to those estimated by subgrain-size piezometry, and (3) whether stresses from subgrain piezometry can be used to estimate the macroscopic average applied stress. Stresses estimated from X-ray diffraction agree well with those made from subgrain-size piezometry in both monomineralic and polymineralic samples. In harzburgites, average stresses are similar in both phases and indicate that in this system, subgrain-size piezometric measurements from a single phase can be used to estimate the bulk stress. 

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2. WATCHER: in-situ failure diagnosis

   https://doi.org/10.1145/3428211  

   Liu, Hongyu; Silvestro, Sam; Zhang, Xiangyu; Huang, Jian; Liu, Tongping (November 2020, Proceedings of the ACM on Programming Languages)

   null (Ed.)
3. In situ observations of sea ice

   Webster, Melinda; Rigor, Ignatius (July 2024, Earth Systems and Environmental Sciences)
4. In-Situ Concolic Testing of JavaScript

   Li, Zhe; Xie, Fei (March 2023, IEEE International Conference on Software Analysis, Evolution and Reengineering (SANER))

   JavaScript (JS) has evolved into a versatile and popular programming language for not only the web, but also a wide range of server-side and client-side applications. Effective, efficient, and easy-to-use testing techniques for JS scripts are in great demand. In this paper, we introduce a holistic approach to applying concolic testing to JS scripts in-situ, i.e., JS scripts are executed in their native environments as part of concolic execution and test cases generated are directly replayed in these environments. We have implemented this approach in the context of Node.js, a JS runtime built on top of Chrome’s V8 JS engine, and evaluated its effectiveness and efficiency through application to 180 Node.js libraries with heavy use of string operations. For 85% of these libraries, it achieved statement coverage ranging between 75% and 100%, a close match in coverage with the hand-crafted unit test suites accompanying their NPM releases. Our approach detected numerous exceptions in these libraries. We analyzed the exception reports for 12 representative libraries and found 6 bugs in these libraries, 4 of which are previously undetected. The bug reports and patches that we filed for these bugs have been accepted by the library developers on GitHub. 

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5. In situ observations of sea ice

   https://doi.org/10.1016/B978-0-323-85242-5.00006-3  

   Webster, Melinda A; Rigor, Ignatius (June 2024, Elsevier)

   Our understanding of sea ice and its role within Earth's climate system is underpinned by observation. Observations come in many forms, from qualitative records to quantitative data, and they have one key thing in common: they are made in situ. Direct measurements comprise most in situ observations; however, remote sensing technologies are also regularly used in situ to measure sea-ice physical properties. In this chapter, we provide an overview of in situ observations (including remote sensing) of sea ice from expeditions, drifting ice stations, autonomous platforms, and ongoing observation programs. We give a chronological account of sea-ice observations, highlighting the technological breakthroughs in sea-ice measurement techniques that have expanded observational capabilities. The chapter concludes with an outlook of future sea-ice observations and ways to bring observational and modeling efforts together to accelerate knowledge of the polar regions and Earth's climate. 

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