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Tidal Signal Propagation in Coastal Aquifers Considering Semi-Permeable Boundaries and Partial Penetration Effects
No full textTidal fluctuations in coastal aquifers offer critical insights into the controls and dynamics of groundwater flow systems. This study presents a new analytical model designed to examine tide-driven variations in groundwater levels, particularly in systems with complex boundary conditions. Unlike previous models, the proposed model incorporates the effects of semi-permeable zones at interfaces and partial boundary penetration near estuaries. Sensitivity analyses were used to evaluate how intricate boundary configurations and specific aquifer characteristics influence the amplitude and phase shift of tidal signals in aquifers. The new analytical approach was also applied to data from a coastal aquifer in Hong Kong, and the results emphasized the importance of accounting for partial estuary penetration when evaluating tidal signal propagation. This approach significantly advances understanding of tidal signal propagation in coastal aquifers, offering a more comprehensive assessment of aquifer behavior that extends beyond hydraulic diffusivity.補正完畢TW
A Performance Index Consistent with Fractional-order Stochastic Dominance
No full textWe propose a performance index for ranking risky projects, termed the fractional-order Omega. The proposed index is consistent with the fractional-order stochastic dominance in between the first- and the second-order stochastic dominance, and bridges the traditional Omega and the second-order Omega. To illustrate its empirical applicability, we utilize the index to develop a market timing strategy. Empirical results show that the market timing strategy, which aims to maximize the fractional-order Omega ex ante, generally performs well ex post.補正完畢TW
Deploying a Skeleton-Based Video Anomaly Detection System on Edge Devices for Human Activity Surveillance
No full textRecent advances in embedded computing have enabled edge devices to run AI models more efficiently, sparking interest in deploying video anomaly detection (VAD) systems for smart surveillance. However, practical implementation requires a careful balance between detection accuracy and computational efficiency. This letter proposes a novel and lightweight anomaly scoring model that integrates a normalizing flow with a multi-scale spatial temporal graph convolutional network (stGCN). The proposed model supports both unsupervised and supervised modes. To evaluate its deployment feasibility, we implement the full VAD pipeline—including YOLOv8n-Pose, BoT-SORT, and the proposed scoring model—on a Raspberry Pi 5. Experimental results demonstrate that our method achieves AUC scores of 86.2% and 72.2% on the ShanghaiTech and UBnormal datasets for unsupervised VAD, respectively, and an AUC score of 82.4% for supervised VAD on the UBnormal dataset, outperforming state-of-the-art methods.補正完畢TW
Development of vacuum-chamber-type capacitive micro-pressure sensors
No full textThis study presents the development of a capacitive pressure sensor tailored for measuring
the dynamic pressure of flow fields. The sensor is fabricated using the UMC 0.18 µm
CMOS-MEMS process, incorporated with additional post-processing steps such as metal
wet etching, supercritical CO2 drying, and parylene encapsulation. The sensing architecture
employs AD7746 as a capacitance-to-voltage converter (CVC), enabling the conversion of
capacitance signals into voltage outputs for enhanced measurement fidelity. Structurally,
the capacitive pressure sensor features a vacuum-sealed diaphragm capsule design with
dual movable circular membranes functioning as sensing electrodes. A contact-mode
capacitive configuration with a trapezoidal or Gong-like vacuum-chamber diaphragm is
adopted to improve linearity and sensitivity. The output sensitivity was determined to be
feasible for measuring dynamic pressure at 1–2 Pa resolution.NSTC補正完畢CH
From Trade Liberalism to Resource Sovereignty: Paradigm Change in Global Raw Materials Governance
No full textGlobal raw materials governance is experiencing a paradigm shift. Long rooted in liberal trade norms and multilateral enforcement, the liberal trading regime faces mounting challenges from sovereignty-based strategies, legal defiance, and normative fragmentation. Drawing on Peter Hall’s typology of policy change and Finnemore and Sikkink’s model of norm emergence and internalization, this article frames the shift as a multi-level process: moving from first-order policy adjustments to second-order institutional strain, and ultimately to third-order redefinitions of trade’s purpose and legitimacy. The article empirically examines three sites of contestation: China’s rare earth export restrictions, Indonesia’s rejection of WTO rulings on nickel (DS592), and the European Union’s expanding use of non-binding Memoranda of Understanding (MoU) in its external raw materials strategy. While MoUs do not replace Economic Partnership Agreements (EPAs), their normative focus on sustainability, value addition, local processing, and negotiated sovereignty signals a strategic realignment aimed at de-risking from China. This article uses process tracing and document analysis to show how contested norms around development, sovereignty, and fair trade reshape global trade instruments. It contributes to trade law and international political economy by highlighting how soft law and strategic diplomacy drive the emergence of a post-liberal resource governance regime.補正完畢NL
