We present our third prototype sensor and a localization method for Automated Guided Vehicles (AGVs), for which small imaging LIght Detection and Ranging (LIDAR) and fusion-based localization are fundamentally important. Our small imaging LIDAR, named the Single-Photon Avalanche Diode (SPAD) LIDAR, uses a time-of-flight method and SPAD arrays. A SPAD is a highly sensitive photodetector capable ...

A Soil-Plant Analysis Development (SPAD) chlorophyll meter can be used as a simple tool for evaluating N concentration of the leaf and investigating the combined effects of nitrogen rate and leaf age on N distribution. We conducted experiments in a paddy field over two consecutive years (2008-2009) using rice plants treated with six different N application levels. N distribution pattern was det...

One of the key hazardous events in railways is signals passed at danger (SPAD). SPAD events are relatively common, most with minor consequence. However, SPAD events with catastrophic consequences happen sufficiently often to be a concern within the rail industry. A SPAD event is a precursor to a train collision or derailment; hence there is a strong focus on measuring and reducing their frequen...

Rice leaves display lateral asymmetry around the midrib, and the narrow side exhibits higher leaf area-based nitrogen concentration (Na) and soil plant analysis development (SPAD) values than the wider side. However, the difference in the relationship between the SPAD of each side and Na of the corresponding lateral half, and the optimal position along the leaf blade for SPAD measurements are n...

Single-photon avalanche diode (SPAD) detector arrays generally suffer from having a low fill-factor, in which the photo-sensitive area of each pixel is small compared to the overall area of the pixel. This paper describes the integration of different configurations of high efficiency diffractive optical microlens arrays onto a 32 × 32 SPAD array, fabricated using a 0.35 µm CMOS technology proce...

The Soil Plant Analysis Development (SPAD) chlorophyll meter is one of the most commonly used diagnostic tools to measure crop nitrogen status. However, the measurement method of the meter could significantly affect the accuracy of the final estimation. Thus, this research was undertaken to develop a new methodology to optimize SPAD meter measurements in rice (Oryza sativa L.). A flatbed color ...

The estimation of nitrogen status, non-destructively, in oilseed rape was performed using spectral reflectance with visible and near infrared reflectance spectroscopy (Vis/NIRS), and SPAD values of the oilseed rape leaves of 30 plots were measured by a SPAD 502 chlorophyll meter, and the research was carried out at experiment field in the Zhejiang University during growing season from 2007 to 2...

We report on the characterization of single-photon avalanche diodes (SPADs) fabricated in standard 140-nm silicon on insulator (SOI) complementary metal-oxide-semiconductor (CMOS) technology. As a methodology for SPAD optimization, a test structure array, called SPAD farm, was realized with several junctions, guard-ring structures, dimensions, etc. In this paper, characterization results of the...

The error in protein tertiary structure prediction is unavoidable, but it is not explicitly shown in most of the current prediction algorithms. Estimated error of a predicted structure is crucial information for experimental biologists to use the prediction model for design and interpretation of experiments. Here, we propose a method to estimate errors in predicted structures based on the stabi...