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gate memory, [6] phase-change memory (PCM), [7][8][9] ferroelectric transistors, [10,11] resistive redox memory (ReRAM), [12][13][14][15][16][17] and magnetic tunnel junction memory. [18] Unfortunately, none of these technologies have been able to meet all the demands of in-memory computing.Electrochemical random-access memory, or ECRAM, is a promising recently developed device for analog inmemory computing. ECRAM stores analog information states by electrochemically shuttling guest dopant ions like lithium ions, protons, or oxygen vacancies between two mixed-conducting host materials. Like ReRAM, ECRAM also stores and switches information through ion migration and the resulting change in valence and electronic conductivity; however, unlike ReRAM, ECRAM contains a solid electrolyte, enabling accurate, linear, and deterministic changes in the resistance state. Since research in ECRAM has dramatically increased from 2017, [21,22] it has met many of the requirements for analog in-memory computing, including linear and symmetric among hundreds of analog states; low read and write currents, voltages, and energies; parallel weight updates; [23,35] CMOS-compatible materials with back-end-of-the-line (BEOL) thermal budgets; [27,28,47] and scaled sub-micrometer sized devices. [24,28] Recently, submicrosecond switching times have been shown using protonsbased ECRAM into polymers, [23,48] MXenes, [34] and tungsten oxides. [28] These developments make ECRAM highly promising for on-line training, which aims to identify the correct analog resistance states (or weights) of a network using the training set of pre-classified data. An even larger application of in-memory computing is inference, which uses a pretrained network to classify new data. Inference is not only simpler to conduct in analog, but is more ubiquitous because all distributed devices, including ones with very limited energy budgets, would use inference to classify new data.An overarching challenge that has precluded ECRAM from inference accelerators is insufficient retention, generally only several hours at room temperature, [22,[25][26][27] and much lower than the ten years at 85 °C benchmark for ReRAM, PCM, and floating gate memory. Moreover, nearly all retention studies utilize an electronic switch that keeps the gate and channel electrodes under "open circuit," while this switch can provide several hours of retention in larger devices >10 µm, leakage currents in the switch will preclude retention times in scaled Electrochemical random-access memory (ECRAM) is a recently developed and highly promising analog resistive memory element for in-memory computing. One longstanding challenge of ECRAM is attaining retention time beyond a few hours. This short retention has precluded ECRAM from being considered for inference classification in deep neural networks, which is likely the largest opportunity for in-memory computing. In this work, an ECRAM cell with orders of magnitude longer retention than previously achieved is developed, and which is anticipated to excee...

This article analyzes the efficacy of border enforcement against smuggling. We argue that walls, fences, patrols, and other efforts to secure porous borders can reduce smuggling, but only in the absence of collusion between smugglers and state agents at official border crossings. When such corruption occurs, border enforcement merely diverts smuggling flows without reducing their overall volume. We also identify the conditions under which corruption occurs and characterize border enforcement as a sorting mechanism that allows high-skilled smugglers to forge alternative border-crossing routes while deterring low-skilled smugglers or driving them to bribe local border agents. Combining a formal model and an archival case study of opium smuggling in Southeast Asia, we demonstrate that border enforcement has conditional effects on the routes and volumes of smuggling, depending on the nature of interactions between smugglers and border agents. By drawing attention to the technological and organizational aspects of smuggling, this article brings scholarship on criminal governance into the study of international relations, and contributes to debates on the effects of border enforcement and border politics more generally.