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The First Year of HARP2/PACE Performance Based on its Ground and On-Orbit Characterization
No full textConference on Characterization and Radiometric Calibration for Remote Sensing (CALCON),August 23 – 26, 2010,Utah State University, Logan, UT, USAThe Hyper-Angular Rainbow Polarimeter-2 (HARP2) was launched on board the Plankton, Aerosol, Cloud and ocean Ecosystem (PACE) mission, in February 2024, for the global measurement of aerosol and cloud properties as well as to provide atmospheric correction over the footprint of the Ocean Color Instrument (OCI). HARP2 is designed to collect data over a wide field of view in the cross-track direction (+/-47deg) allowing for global coverage in about two days, as well as an even wider field of view in the along-track direction (+/-54 deg) providing measurements over a wide range of scattering angles. HARP2 samples 10 angles at 440, 550, and 870nm focusing on aerosol and surface retrievals, and up to 60 angles at 670nm for the hyper-angular retrieval of cloud microphysical properties. The HARP2 instrument collects three nearly identical images with linear polarizers aligned at 0°, 45°, and 90° that can be converted to push-broom images of the I, Q, and U Stokes parameters for each angle, and each wavelength. The HARP2 technology was first demonstrated with the HARP CubeSat satellite which collected a limited dataset for 2 years from 2020 to 2022. HARP2 extends these measurements to a full global coverage in two days, seven days a week.This talk will show a brief description of the instrument and will focus on the calibration and characterization of the HARP2 instrument at the ground and on-orbit. The calibration and characterization of such a wide FOV instrument with polarization sensitivity produces particular challenges that are not common on other classes of instrument with narrower FOV. HARP2 was characterized at the ground from the spectral, radiometric, and polarimetric perspectives, as function of temperature, and aiming for high accuracy across the whole field of view of the instrument. Multiple techniques have been developed to address this characterization, which has resulted in about 1TByte of calibration data.Once in orbit, the HARP2 team has also developed special strategies for the continued monitoring of the calibration parameters as well as for tracking the absolute calibration of the system. These strategies include lunar and solar calibration, flat field, dark current monitoring, vicarious calibrations looking at well know ground target, intercomparison between sensors, etc. Results from the ground and on-orbit calibration will be presented and discussed in detail.https://digitalcommons.usu.edu/calcon/CALCON2025/All2025Content/1
State Protests, Slow Housing Starts, Cricket Fundraiser
No full textMaryland cuts off SNAP funding without federal reassurances of reimbursements; state eliminates 502 jobs to save $27m. Protests gather steam against deportation flight company Avelo Airlines, Silver Spring demolition firm ACECO, and Maryland Israel Development Center, a state investment agency. Montgomery County Planning Staff report survey results on why developers with preliminary approvals are not building. With MCPS wanting to repurpose the new Crown High School building, competing petitions. A young, refugee, immigrant county council candidate proposes a cricket fundraiser. Music by Dear Daria.https://open.spotify.com/episode/3iF2r5q5eUy60DXKdlATD
A Cross-Cultural Crash Pattern Analysis in the United States and Jordan Using BERT and SHAP
No full textUnderstanding the cultural and environmental influences on roadway crash patterns is essential for designing effective prevention strategies. This study applies advanced AI techniques, including Bidirectional Encoder Representations from Transformers (BERT) and Shapley Additive Explanations (SHAP), to examine traffic crash patterns in the United States and Jordan. By analyzing tabular data and crash narratives, the research reveals significant regional differences: in the USA, vehicle overturns and roadway conditions, such as guardrails, are major factors in fatal crashes, whereas in Jordan, technical defects and driver behavior play a more critical role. SHAP analysis identifies “driver” and “damage” as pivotal terms across both regions, while country-specific terms such as “overturn” in the USA and “technical” in Jordan highlight regional disparities. Using BERT/Bi-LSTM models, the study achieves up to 99.5% accuracy in crash severity prediction, demonstrating the robustness of AI in traffic safety analysis. These findings underscore the value of contextualized AI-driven insights in developing targeted, region-specific road safety policies and interventions. By bridging the gap between developed and developing country contexts, the study contributes to the global effort to reduce road traffic injuries and fatalities.https://www.mdpi.com/2079-9292/14/2/27
Stable Nitrogen Isotope Analysis of Amino Acids by Orbitrap Mass Spectrometry: Application for Extraterrestrial Samples
No full textBackground Obtaining isotopic data on soluble organic compounds, such as amino acids, in extraterrestrial samples is crucial for understanding their origins, prebiotic chemistry, and potential contamination. Conventional GC-IRMS requires grams of material to measure isotopic compositions, limiting the analysis of low-concentration organics in meteorites and other astromaterials. We present an Orbitrap-based method optimized for nitrogen isotopic analysis of amino acids. Results This method determines δ¹⁵N values for picomole quantities (< 150 pmol) with 3‰–8‰ precision and accuracy within 2‰ compared with elemental analysis. Our approach was validated using amino acid enantiomer standards and a CM2 Murchison meteorite sample. The Murchison results demonstrate that comparable precision can be achieved on analytes extracted from a total sample size representing less than 7% of the mass previously required for CSIA analysis of the same meteorite. Significance These results highlight the potential of Orbitrap mass spectrometry for δ¹⁵N measurements with less material and lower analyte concentrations. This technique improves our ability to trace the origins and synthetic pathways of amino acids, providing valuable insights into prebiotic chemistry and possible abiotic mechanisms for organic compound formation in primitive solar system materials. Nitrogen isotopes serve as a powerful tool for distinguishing biological from non-biological sources, aiding in the identification of contamination in meteoritic samples and improving the reliability of analyses involving rare extraterrestrial materials.This material is based upon work supported by NASA under Contract NNM10AA11C issued through the New Frontiers Program and awards NNH21ZDA001N-ORSAPSP and NNH09ZDA007O. H.L.M. and K.K.F. are supported by the Center for Research and Exploration in Space Science and Technology II cooperative agreement with NASA and Catholic University of America and the University of Maryland, Baltimore County, under Award No. 80GSFC24M0006. H.L.M., K.K.F., J.P.D., D.P.G., and J.E.E. acknowledge NASA's Planetary Science Division Internal Scientist Funding Program through the Fundamental Laboratory Research (FLaRe) Work Package at NASA Goddard Space Flight Center and NASA Planetary Science Division Funding through the Goddard Center for Astrobiology.https://onlinelibrary.wiley.com/doi/abs/10.1002/rcm.1012
Computing Safe Control Inputs using Discrete-Time Matrix Control Barrier Functions via Convex Optimization
No full textControl barrier functions (CBFs) have seen widespread success in providing forward invariance and safety guarantees for dynamical control systems. A crucial limitation of discrete-time formulations is that CBFs that are nonconcave in their argument require the solution of nonconvex optimization problems to compute safety-preserving control inputs, which inhibits real-time computation of control inputs guaranteeing forward invariance. This paper presents a novel method for computing safety-preserving control inputs for discrete-time systems with nonconvex safety sets, utilizing convex optimization and the recently developed class of matrix control barrier function techniques. The efficacy of our methods is demonstrated through numerical simulations on a bicopter system.http://arxiv.org/abs/2510.0992
Simultaneous retrieval of aerosol optical depth, spectral absorption and layer height from DSCOVR EPIC using MAIAC algorithm
No full textA novel MAIAC algorithm is described for joint retrievals of the aerosol optical depth, spectral absorption and layer height (ALH) from DSCOVR EPIC observations in the UV-Vis-NIR spectral range including atmospheric oxygen A- and B-bands. While the oxygen bands have been used to estimate ALH in several existing algorithms, MAIAC for the first time employs a synergy between the UV and O₂ A,B-bands to enhance sensitivity to the height of aerosol layer and retrieves it simultaneously with other major aerosol properties. The ALH retrieval capability is illustrated using several examples for smoke and dust aerosols over different parts of the globe. A global AERONET validation of aerosol properties based on the full EPIC data record (mid-2015–2025) shows an accuracy of AOD with correlation coefficient R ∼ 0.71-0.73, RMSE ∼ 0.4, and expected error EE ∼ 20%. While accuracy of AOD is moderate due to the backscattering view geometry of EPIC, achieved agreement of spectral single scattering albedo (SSA) at 443 and 680 nm with AERONET inversion data is very good: the expected error ± 0.03 agrees with AERONET uncertainty, the RMSE is within 0.02–0.03, and bias is within ±0.01. The ALH product was validated globally for the overlapping EPIC- CALIOP CALIPSO period using the CALIPSO total backscatter weighted height. The ALH validation shows a robust performance with global RMSE ∼ 1.1 km and 60%–77% of retrievals within EE = ±1 km. The retrieved ALH is lower than CALIOP ALHC by 0.45–0.75 km over land and is unbiased over the ocean. This new capability and suite of aerosol products, designed to support both the Earth system modeling and the air quality applications, are part of the version 3 MAIAC EPIC algorithm. The v3 algorithm has recently completed reprocessing of the EPIC record covering the period of 2015–2025.
: subscriptThe author(s) declare that financial support was received for the research and/or publication of this article. This work was supported by the NASA DSCOVR program, NASA PACE program (19-PACESAT19-0039) and by the Office of Naval Research.https://www.frontiersin.org/journals/remote-sensing/articles/10.3389/frsen.2025.1677438/ful
Cosmic-ray modulation over the past 10 years observed with CALET on the International Space Station
No full text39th International Cosmic Ray Conference (ICRC2025), July 15–24 2025,Geneva, SwitzerlandAuthors: CALET Collaboration, O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, E. Berti, P. Betti, G. Bigongiari, W.R. Binns, M. Bongi, P. Brogi, A. Bruno, N. Cannady, G. Castellini, C. Checchia, M.L. Cherry, G. Collazuol, G.A. de Nolfo, K. Ebisawa, A. W. Ficklin, H. Fuke, S. Gonzi, T.G. Guzik, T. Hams, K. Hibino, M. Ichimura, M.H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kobayashi, K. Kohri, H.S. Krawczynski, J.F. Krizmanic, P. Maestro, P.S. Marrocchesi, M. Mattiazzi, A.M. Messineo, J.W. Mitchell, S. Miyake, A.A. Moiseev, M. Mori, N. Mori, H.M. Motz, K. Munakata, S. Nakahira, J. Nishimura, M. Negro, S. Okuno, J.F. Ormes, S. Ozawa, L. Pacini, P. Papini, B.F. Rauch, S.B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, P. Spillantini, F. Stolzi, S. Sugita, A. Sulaj, M. Takita, T. Tamura, T. Terasawa, S. Torii, Y. Tsunesada, Y. Uchihori, E. Vannuccini, J.P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, and W. V. ZoberThe CALorimetric Electron Telescope (CALET) on the International Space Station has been measuring cosmic rays and gamma rays since October 2015. In addition to the high-energy trigger, CALET operates a low-energy electron (LEE) trigger at high geomagnetic latitudes, enabling measurements of 1–10 GeV electrons. Using this LEE trigger mode, CALET has observed the solar modulation of low-energy electrons and protons over nearly ten years, including the solar minimum and the solar maximum of the 25th solar cycle. The electron and positron flux exhibited a continuous decrease beginning in the ascending phase of the 25th solar cycle, reaching its lowest values in 2024. By comparing electron and proton count rates at the same average rigidity of 3.8 GV, we observed a clear charge-sign dependence of solar modulation. We also identified a clear hysteresis structure over the ascending and descending phases of the solar cycle. This hysteresis persisted across the solar maximum, covering the period of the solar magnetic polarity reversal. Furthermore, CALET detected Forbush decreases of electrons and protons in temporal agreement with ground-based neutron monitor observations. The larger decrease observed by CALET compared with ground-based neutron monitors suggests the rigidity dependence of solar modulation. These results demonstrate CALET’s capability to resolve charge-sign–dependent effects and transient phenomena in the CR propagation in the heliosphere, providing valuable input for models of solar modulation.We gratefully acknowledge JAXA’s contributions to the development of CALET and to the operations aboard the JEM-EF on the ISS. This work was supported in part by JSPS Grant-in-Aid for Scientific Research (S) No. 26220708, No. 19H05608, and No. 24H00025, JSPS Grant-inAid for Scientific Research (B) No. 24K00665, and by the MEXT Supported Program for the Strategic Research Foundation at Private Universities (2011-2015) (No. S1101021) at Waseda University. The CALET effort in Italy is supported by ASI under Agreement No. 2013-018-R.0 and its amendments. The CALET effort in the United States is supported by NASA through Grants No. NNX16AB99G, No. NNX16AC02G, and No. NNH14ZDA001N-APRA-0075.https://pos.sissa.it/501/1337
Change Management: from Initial Configuration to Reliably Updating
No full textThis paper focuses on change management within system and software engineering, particularly emphasizing the journey from initial design to reliable updates in operational environments. It outlines the importance of baselining design solutions through various review stages and meticulously details the processes of System Configuration Management (CM), including change control during design and software release. The text also explores the challenges posed by advanced technologies (like Industry 4.0/5.0) to traditional systems engineering, suggesting solutions such as modern technology-based tools (AI, MBSE), shared engineering workspaces, and understanding software's "context of use." Finally, it addresses Software Configuration Management (SCM) processes, the use of CM repositories, and strategies for patching with reduced downtime, concluding with the critical role of enhanced organizational learning in retaining knowledge of the design rationale for built interfaces, which must be maintained to support effective update processes.https://papers.ssrn.com/abstract=540373
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No full textFor millennia, the observation and understanding of the natural world has served as a meditative tool to find spiritual balance. This study uses sculpted clay forms and repetitive making processes as a case study on the process of finding balance to conflicting and disparate opposites like growth and decay in nature or control and chaos. This study outlines a number of ways humans seek balance. It also addresses the perceived control on these balances. Each sculpture in the exhibition–"Equilibrium”–is dedicated to a particular aspect in nature found within the context of growth and decay of plants. The need for balance and control is addressed by psychologists, educators and artists, arguing that the balance is not found in between two extremes but instead in the knowledge of the coexistence of perceived extremes in tandem.n/
Amphipathic Alpha-Helical Peptides AH1 and AH3 Facilitate Immunogenicity of Enhanced Green Fluorescence Protein in Rainbow Trout (Oncorhynchus mykiss)
No full textVaccination is the most effective method to counteract infectious diseases in farmed fish. It secures aquaculture production and safeguards the wild stock and aquatic ecosystem from catastrophic contagious diseases. In vaccine development, recombinant subunit vaccines are favorable candidates since they can be economically produced in large quantities without growing many pathogens, as in inactivated or attenuated vaccine production. However, recombinant subunit vaccines are often weak or deficient in immunogenicity, resulting in inadequate defenses against infections. Technologies that can increase the immunogenicity of recombinant subunit vaccines are in desperate need. Enhanced green fluorescence protein (EGFP) has a low antigenicity and is susceptible to folding changes and losing fluorescence after fusing with other proteins. Using these valuable features of EGFP, we comprehend two amphipathic alpha-helical peptides, AH1 and AH3, derived from Hepatitis C virus and Influenza A virus, respectively, that can induce high immune responses of their fused EGFP in fish without affecting their folding. AH3-EGFP has the most elevated cell binding, significantly 62% and 36% higher than EGFP and AH1-EGFP, respectively. Immunizations with AH1-EGFP or AH3-EGFP significantly induced higher anti-EGFP antibody levels 300–500-fold higher than EGFP immunization after the boost injection in rainbow trout. Our results suggest that AH1 and AH3 effectively increase the immunogenicity of EGFP without influencing its structure. Further validation of their value in other recombinant proteins is necessary to demonstrate their broader utility in enhancing the immunogenicity of subunit vaccines. We also suggest that EGFP and its variants are promising candidates for initially screening proper immunogenicity-enhancing peptides or proteins to advance recombinant subunit vaccine development.This research was funded by the University of Maryland, Baltimore County STRT7TEN1113 to T.-T.W.https://www.mdpi.com/2077-1312/13/8/149