161 research outputs found
Efficient Monitoring of Parametric Context Free Patterns
Recent developments in runtime verification and monitoring show that parametric regular and temporal logic specifications can be efficiently monitored against large programs. However, these logics reduce to ordinary finite automata, limiting their expressivity. For example, neither can specify structured properties that refer to the call stack of the program. While context-free grammars (CFGs) are expressive and well-understood, existing techniques of monitoring CFGs generate massive runtime overhead in real-life applications. This paper shows for the first time that monitoring parametric CFGs is practical (on the order of 10% or lower for average cases, several times faster than the state-of-the-art). We present a monitor synthesis algorithm for CFGs based on an LR(1) parsing algorithm, modified with stack cloning to account for good prefix matching. In addition, a logic-independent mechanism is introduced to support partial matching, allowing patterns to be checked against fragments of execution traces
RESEARCH ON INTELLIGENT MANUFACTURING INNOVATION ENGINEERING OF GARMENT ENTERPRISES BASED ON CONSUMER PSYCHOLOGY
Development of Robust Behaviour Recognition for an at-Home Biomonitoring Robot with Assistance of Subject Localization and Enhanced Visual Tracking
Our research is focused on the development of an at-home health care biomonitoringmobile robot for the people in demand. Main
task of the robot is to detect and track a designated subject while recognizing his/her activity for analysis and to provide warning
in an emergency. In order to push forward the system towards its real application, in this study, we tested the robustness of the
robot system with several major environment changes, control parameter changes, and subject variation. First, an improved color
tracker was analyzed to find out the limitations and constraints of the robot visual tracking considering the suitable illumination
values and tracking distance intervals.Then, regarding subject safety and continuous robot based subject tracking, various control
parameters were tested on different layouts in a room. Finally, the main objective of the system is to find out walking activities for
different patterns for further analysis. Therefore, we proposed a fast, simple, and person specific new activity recognition model by
making full use of localization information, which is robust to partial occlusion. The proposed activity recognition algorithm was
tested on different walking patterns with different subjects, and the results showed high recognition accuracy
Optical bulk-boundary dichotomy in a quantum spin Hall insulator
The bulk-boundary correspondence is a key concept in topological quantum
materials. For instance, a quantum spin Hall insulator features a bulk
insulating gap with gapless helical boundary states protected by the underlying
Z2 topology. However, the bulk-boundary dichotomy and distinction are rarely
explored in optical experiments, which can provide unique information about
topological charge carriers beyond transport and electronic spectroscopy
techniques. Here, we utilize mid-infrared absorption micro-spectroscopy and
pump-probe micro-spectroscopy to elucidate the bulk-boundary optical responses
of Bi4Br4, a recently discovered room-temperature quantum spin Hall insulator.
Benefiting from the low energy of infrared photons and the high spatial
resolution, we unambiguously resolve a strong absorption from the boundary
states while the bulk absorption is suppressed by its insulating gap. Moreover,
the boundary absorption exhibits a strong polarization anisotropy, consistent
with the one-dimensional nature of the topological boundary states. Our
infrared pump-probe microscopy further measures a substantially increased
carrier lifetime for the boundary states, which reaches one nanosecond scale.
The nanosecond lifetime is about one to two orders longer than that of most
topological materials and can be attributed to the linear dispersion nature of
the helical boundary states. Our findings demonstrate the optical bulk-boundary
dichotomy in a topological material and provide a proof-of-principal
methodology for studying topological optoelectronics.Comment: 26 pages, 4 figure
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