arXiv subjects

Shuo Guo

Publications and source records attributed to Shuo Guo.

5 recordsLinked to original sources

arXiv2026

Natural-Language Agent Harnesses

Agent performance is strongly shaped by the surrounding harness: the external execution system around a model that organizes a task run. Yet this logic is usually buried in tightly coupled controller code, which makes harnesses hard to inspect, compare, transfer, and ablate. This paper asks whether the reusable design pattern of an agent harness can be represented as an executable natural-language object. We introduce Natural-Language Agent Harnesses (NLAHs), editable documents that describe run-level harness policy, and Intelligent Harness Runtime (IHR), a shared runtime that interprets these documents into agent calls, handoffs, state updates, validation gates, and artifact contracts. Across coding, terminal-use, and computer-use benchmarks, IHR-executed NLAHs achieve comparable task outcomes to code and prompted realizations, while exposing much shorter static harness policies. Module ablations further show that explicit harness modules are analyzable. These results suggest that agent harnesses can be turned from incidental glue around models into scientific representation objects.

cs.CL↗

arXiv2025

Bacterial turbulence at compressible fluid interfaces

Dense bacterial suspensions at fluid interfaces provide a natural platform to explore active turbulence in a dimensional mismatch: active units are restricted to a two-dimensional surface, while the induced flows extend into the surrounding three-dimensional liquid. Using hydrophobic Serratia marcescens at the air-water interface, we realize interfacial bacterial turbulence as a distinct class of active turbulence. The system exhibits compressible in-plane flows, with vortex size initially increasing with the thickness of the underlying fluid and saturating near 100 $\mu$ m, independent of bacterial length. This behavior contrasts sharply with bulk active turbulence, where correlation length typically scales with system size. Hydrodynamic theory, together with direct measurements of the three-dimensional flow field, shows that the coupling between interfacial and bulk flows sets the emergent length scale. Our results uncover the fundamental physics of interfacial bacterial turbulence and open new strategies for geometric control of collective active flows.

cond-mat.soft↗

arXiv2025

A Survey of Synchronization Technologies for Low-power Backscatter Communication

Synchronization is a fundamental enabler for low-power backscatter communication systems, where passive or semi-passive tags modulate ambient RF signals for ultra-low-power data transfer. In this survey, we review recent advances in synchronization techniques across Bluetooth Low Energy (BLE), Long-Term Evolution (LTE), and WiFi-based backscatter platforms. We categorize existing methods by their synchronization granularity, accuracy, compatibility, and power cost. We then compare representative systems including PassiveBLE, Bitalign, LScatter, SyncLTE, LiTEfoot, SyncScatter, and BiScatter, highlighting design trade-offs and performance metrics. Furthermore, we delve into the trade-offs between high throughput and low power synchronization, examining key approaches and challenges such as the balance between throughput, synchronization accuracy, and power consumption in various backscatter systems. Finally, we discuss open challenges and outline future directions toward scalable, secure, and ultra-low-power backscatter synchronization.

cs.DC↗

arXiv2023

Transport and Energetics of Bacterial Rectification

Randomly moving active particles can be herded into directed motion by asymmetric geometric structures. Although such a rectification process has been extensively studied due to its fundamental, biological, and technological relevance, a comprehensive understanding of active matter rectification based on single particle dynamics remains elusive. Here, by combining experiments, simulations, and theory, we study the directed transport and energetics of swimming bacteria navigating through funnel-shaped obstacles -- a paradigmatic model of rectification of living active matter. We develop a microscopic parameter-free model for bacterial rectification, which quantitatively explains experimental and numerical observations and predicts the optimal geometry for the maximum rectification efficiency. Furthermore, we quantify the degree of time irreversibility and measure the extractable work associated with bacterial rectification. Our study provides quantitative solutions to long-standing questions on bacterial rectification and establishes a generic relationship between time irreversibility, particle fluxes, and extractable work, shedding light on the energetics of non-equilibrium rectification processes in living systems.

cond-mat.soft↗

arXiv2018

Symmetric shear banding and swarming vortices in bacterial "superfluids"

Bacterial suspensions--a premier example of active fluids--show an unusual response to shear stresses. Instead of increasing the viscosity of the suspending fluid, the emergent collective motions of swimming bacteria can turn a suspension into a "superfluid" with zero apparent viscosity. Although the existence of active "superfluids" has been demonstrated in bulk rheological measurements, the microscopic origin and dynamics of such an exotic phase have not been experimentally probed. Here, using high-speed confocal rheometry, we study the dynamics of concentrated bacterial suspensions under simple planar shear. We find that bacterial "superfluids" under shear exhibit unusual symmetric shear bands, defying the conventional wisdom on shear-banding of complex fluids, where the formation of steady shear bands necessarily breaks the symmetry of unsheared samples. We propose a simple hydrodynamic model based on the local stress balance and the ergodic sampling of nonequilibrium shear configurations, which quantitatively describes the observed symmetric shear-banding structure. The model also successfully predicts various interesting features of swarming vortices in stationary bacterial suspensions. Our study provides new insights into the physical properties of collective swarming in active fluids and illustrates their profound influences on transport processes.

cond-mat.soft↗