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Seismically induced soft-sediment deformation in alluvial fans : mechanisms and implications for geological evolution of the Ordos Basin (China)
Bilal, Ahmer; Yang, Renchao; Chen, Shaojie; Lenhardt, Nils; Mughal, Muhammad Saleem; Kontakiotis, George (Elsevier, 2025-12)
Well-exposed soft-sediment deformation structures (SSDS) outcrops are rare and often mistaken for tectonic folds, leading to limited research and underutilisation in sedimentary geology. The Taitongshan section of the Middle-Permian Shihezi Formation in the Ordos Basin, China, provides insights into SSDS, whose spatial distribution and sedimentation reveal information about paleoenvironments, tectonic movements, and seismic events crucial for understanding basin development. This study uses fieldwork and sedimentology to investigate SSDS formation and triggers. Fieldwork identified six siliciclastic facies with SSDS and associated syndepositional structures. Sedimentological interpretations highlighted the connection between seismic activity and the genesis of SSDS, reinforcing their value as proxies for tectonic events in basin evolution studies. SSDS formation is triggered by seismic shaking, initiating liquefaction, erosion, slurry-clump formation, hydroplastic deformation, mass consolidation, and lithification. Rayleigh waves-induced liquefaction in partially-lithified subsurface sediments forms water escape structures. Provenance analysis reveals seismically active, orogenic source areas southwest and southeast of the NCC, with significant uplift and erosion during the Middle-Permian. Key findings indicate that the Middle-Permian braided river facies of the Taitongshan section originated from the Qilian Orogenic Belt, followed by a subsequent provenance shift towards the eastern-North Qinling Orogeny (NQLO), highlighting the dynamic tectonic forces driving rapid provenance shifts, further shaping sediment deposition and advancing basin evolution. Furthermore, the southeastern NCC experienced a more rapid uplift than the southwestern part during that time. These facies were deposited on the distal fan region of a prograding alluvial fan, where seismites likely formed due to active seismicity in the NQLO. The study identifies inter-facies shifts during seismite formation, introducing an innovative concept beyond traditional in-situ genesis models and broadening the understanding of sedimentary dynamics. This critical role of SSDS in sedimentation architecture enhances the understanding of basin evolution in sedimentary geology and provides a framework for interpreting similar structures globally. HIGHLIGHTS • SSDS formation driven by seismic activity reveals complex basin evolution processes. • Taitongshan section shows braided stream and sheet flood deposits on alluvial fan. • Seismic shocks induce SSDS via liquefaction in partially lithified sediments. • New SSDS inter-facies shift concept challenges traditional in-situ models. • Provenance analysis links Qilian and North Qinling Orogenies to tectonic uplift patterns.
Post-commencement finance creditors and post-commencement creditors – one and the same? Mashwayi Projects (Pty) Ltd v Wescoal (Pty) Ltd 2025 3 SA 441 (SCA)
Swart, Willem Jacobus Christiaan (LexisNexis, 2026-02)
Hierdie vonnisbespreking is 'n kritiese oorweging van die Hoogste Hof van Appèl se beslissing in Mashwayi Projects (Pty) Ltd v Wescoal (Pty) Ltd 2025 3 SA 441 (SCA), waarin die hof moes beslis wie almal as krediteure beskou moet word vir doeleindes van stemming oor 'n voorgestelde ondememingsreddingsplan ingevolge Hoofstuk 6 van die Maatskappywet 71 van 2008 (die Wet). Strydig met die beslissings van die verhoorhof, wat beslis het dat slegs skuldeisers ten tye van die aanvang van ondernemingsredding mag stem, het die Hoogste Hof van Appèl bevind dat die term "skuldeiser", soos gebruik in die betrokke bepalings van die Wet, sy gewone grammatikale betekenis behou en dus beide voor- en na-aanvang skuldeisers insluit, tensy die Wet uitdruklik anders bepaal. Die hof het voorts bevind dat 'n beperkende uitleg wat na-aanvang skuldeisers van stemming uitsluit, moontlik ongrondwetlik sal wees aangesien dit indruis teen die reg op gelyke beskerming in artikel 9 van die Grondwet van die Republiek van Suid-Afrika, 1996. Hoewel die beslissing die regsposisie van na-aanvangsfmansierings skuldeisers versterk, word in hierdie vonnisbespreking betoog dat die hof se uitlegmetodologie problematies is. Die hof het versuim om die term "skuldeiser" in konteks uit te lê met inagneming van die struktuur en doelstellings van Hoofstuk 6, soos voorgeskryf in artikel 5 van die Wet. Spesifieke verwysings na die statutêre raamwerk, insluitend bepalings wat betrekking het op 'n "geaffekteerde persoon", kompromieë met skuldeisers, en die prioriteitsreëling van eise ingevolge artikel 135, is onvoldoende verreken. Voorts word die regsposisie van Mashwayi Projects herbeskou. Hoewel die eise aan Mashwayi ná die aanvang van die ondememingsreddingsproses gesedeer is, het die eisoorsaak onderliggend aan die eis reeds voor daardie tyd bestaan. Daar word geargumenteer dat die fokus eerder op die ontstaan van die eis, en met die identiteit van die houer nie, behoort te val. Die hof se klassifikasie van Mashwayi as 'n na-aanvangsfmansierings skuldeiser is dus onvanpas. Die gevolgtrekking word gemaak dat alhoewel die beslissing van die HHA prakties voordelig mag wees vir die doeltreffende funksionering van ondernemingsreddings-prosesse, die hof onvoldoende gevolg gegee het aan 'n sistemiese en doelgerigte uitlegbenadering wat die Wet vereis, en dus 'n wanbalans geskep het tussen die belange van voor- en na-finansierings skuldeisers.
Level-crossing downsampling for quantization error reduction in sine wave estimation
De Beer, Dirk Johannes; Joubert, Trudi-Heleen (Institute of Electrical and Electronics Engineers, 2026-02)
This work introduces a digital postprocessing algorithm—level-crossing downsampling (LC-DS)—for estimating sine wave parameters from sequences of quantized values acquired by standard ADCs. LC-DS emulates level-crossing sampling by retaining only transition points, reducing correlated quantization error, and accelerating least-squares regression (LSR). Its performance is benchmarked against uniform LSR and calibrated sinefit to highlight accuracy and computational tradeoffs. Across a wide dynamic range, LC-DS consistently outperforms uniform sampling and approaches the accuracy of calibrated sinefit for low-level signals, while remaining up to two orders of magnitude faster for large datasets. Unlike conventional methods, LC-DS scales efficiently with data size, enabling real-time estimation without hardware modifications. Practical and simulated experiments, including electrochemical impedance spectroscopy, confirm robustness under conditions such as signal saturation. These results position LC-DS as a compelling alternative for applications requiring both high precision and computational efficiency.
Learning-based moving horizon autonomous control of a chemical reactor
Sun, Bei; Kong, Peng; Le Roux, Johan Derik; Craig, Ian Keith; He, Mingfang; Yang, Chunhua (Elsevier, 2025-12)
This paper proposes a learning-based moving horizon autonomous control of a chemical reactor (LMHAC) approach for chemical reactor with multiple operating conditions. In the proposed LMHAC scheme, model-based control, model-free control and process modeling are integrated in a moving horizon framework. A control switching logic makes a selection between model predictive control (MPC) and adaptive dynamic programming (ADP) depending on whether the model parameters are known or unknown under the current operating condition. To be compatible with the moving horizon framework, the conventional ADP is fitted into a finite horizon composed of two different stages, namely a learning stage and a control-identification stage. In the learning stage, a constrained finite-horizon ADP (CFADP) first learns an approximated optimal controller from the collected input-state information pair generated by an initial admissible control. In the control-identification stage, the approximated optimal control is applied to the process to generate a sequence of input-state information pairs which is then utilized in turn to identify the unknown model parameters. The LMHAC framework is capable of providing the optimal or nearly optimal control for different operating conditions online and incrementally enlarge the known domain of system dynamics. The feasibility and performance of the proposed approach are illustrated via a case study.
Opening the black box of disaster recovery in SMEs : unpacking the antecedent roles of anticipation capabilities, risk management culture and supply chain agility
Acquah, Innocent Senyo Kwasi; Arhin, Michael; Tchouchu, Emmanuel; Botwe-Koomson, Allswell (Emerald, 2026)
PURPOSE : This study examines how risk management culture fosters disaster recovery and analyses the serial mediation roles of anticipation capabilities and supply chain agility, while assessing opportunities to improve risk management culture, anticipation capabilities and supply chain agility to enhance disaster recovery. Further, the study examines the necessity of risk management culture, anticipation capabilities and supply chain agility for disaster recovery. DESIGN/METHODOLOGY/APPROACH : We combined Partial Least Squares Structural Equation Modelling, Importance-Performance Map Analysis and Necessary Condition Analysis to explore the sufficient and necessary roles of risk management culture, anticipation capabilities and supply chain agility in enhancing or enabling disaster recovery among a sample of 357 Ghanaian Small and Medium-sized Enterprises. FINDINGS : The findings suggest that risk management culture and supply chain agility, but not anticipation capabilities, have a positive influence on disaster recovery. Moreover, anticipation capabilities and supply chain agility serially mediate the positive nexus between risk management culture and disaster recovery. Furthermore, the findings indicate that risk management culture and supply chain agility, rather than anticipation capabilities, are necessary for effective disaster recovery. ORIGINALITY/VALUE : We present one of the first attempts to broaden our understanding of the drivers of disaster recovery among SMEs, while also providing managers with actionable insights regarding the sufficient and necessary antecedents of disaster recovery.