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...

a pot experiment was carried out to determine the effect of foliage spraying of silicon (si) on growth and ornamental characteristics of calendula grown under salt stress and greenhouse conditions. a factorial experiment based on completely randomized design was conducted with 3 levels of si (0, 50 and 100 mg/l) and 3 levels of nacl (0, 100 and 200 mm) with 4 replications. at flowering stage, s...

monly used instruments is a Minolta SPAD (soil plant analysis development) meter. The SPAD meter measures the difference in light absorption at 430 and 750 nm (Wood et al., 1992). The former is the transmittance peak for chlorophyl ‘a’ and ‘b’, and the latter is in the near-infrared region. The instrument converts the difference in light absorption at these two wavelengths into a numerical SPAD...

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 hydroponic experiment carried out to study the effect of five Cd levels on growth and photosynthesis of two tomato cultivars showed that the addition of 0.1 micromol/L Cd induced a slight increase in plant height of Hezuo 903 and the SPAD (the Soil-Plant Analyses Development) value of the 2 cultivars. However, at higher Cd levels, i.e., 1 and 10 micromol/L, root length and volume, plant heigh...

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...