KDP single crystals were grown in aqueous solution by using "point seeds" with a defined crystallographic direction of 59° to the Z axis. When hillock slopes on the (100) face of KDP crystals were measured within the supersaturation (σ) range of 0 < σ ≤ 0.06, the slope of hillocks with hollow cores depended nonlinearly on supersaturation. Below σ = 0.02, the hillock slope depended on supersatur...

Topic tracking is an important task of Topic Detection and Tracking (TDT). Its purpose is to detect stories, from a stream of news, related to known topics. Each topic is “known” by its association with several sample stories that discuss it. In this paper, we propose a new method to build the keywords dependency profile (KDP) of each story and track topic basing on similarity between the profi...

Multiparameter radar measurements of rainfall, namely, reflectivity factor ZH , differential reflectivity ZDR , and specific differential phase KDP lie in a constrained threedimensional (3-D) space and therefore measurement of ZH , ZDR , or KDP should be consistent with the other two. This selfconsistency relationship between ZH , ZDR , and KDP is valid when the radar resolution volume is homog...

In order to improve the understanding of microphysical characteristics raindrop size distribution (DSD) under different rainfall rates (R) classes, and broaden knowledge impact radar wavelengths R classes on QPE dual-polarization radars in Tianshan Mountains, a typical arid area China, we investigated DSD across dual-polarimetric relationships based data from PARSIVEL2 disdrometer at Zhaosu Mou...

Multiparameter radar measurements were made during a heavy rainfall event accompanied by hail in Colorado. Rainfall rates R and accumulation for this event were estimated using S-band specific differential phase KDP, reflectivity factor ZH, and X-band specific attenuation AH3. These estimates were compared with measurements from a ground-based rain gauge. Both R–KDP and R–AH3 relations were in ...

Noncentrosymmetric potassium dihydrogen phosphate (KH2PO4 or KDP) in the tetragonal crystal phase is arguably the most extensively studied nonlinear optical crystal in history. It has prolific applications ranging from simple laser pointers to laser inertial confinement fusion systems. Recently, type IV high-pressure KDP crystal sheets with a monoclinic crystal phase having centrosymmetric prop...

Coincidental radar measurements and in situ ground-truth observations of large, oblate hail has allowed new insights into the fall mode of oblate hailstones. The effect of the fall mode upon hail-detection algorithms using multi-parameter radar is investigated and discussed, as is the vexed problem of extracting realistic rainfall rates in regions where hail and rain coexist. Observations prese...

The modified strong dipole–proton coupling (MSDPC) model, which predicted several static and dynamic dielectric properties of KH2PO4 or KDP-type ferroelectrics, was used to investigate the properties of these crystals on the local scale. Results calculated by molecular dynamics (MD) simulation show that both order–disorder and displacive characteristics of one PO4 dipole are present in KDP and ...

Microwave attenuation in rain at C-band. observed in radar data from Alberta. Canada, has been assessed by means of two different estimators: one employing KDP measured simultaneously by an S-band radar and the other a comparison of synchronised Sand C-band reflectivity measurements. While good agreement between the two has been found in some cases, in others the second method gave a larger est...

Due to nonlinear atomic polarization, crystals can emit a different frequency of light than absorbed. In order to see the second order effects of atomic polarization, which cause a doubling in the frequency of the incident light, the incident light must be an intense and coherent source, like a laser. Potassium Dihydrogen Phosphate (KDP) is a crystal that exhibits these nonlinear polarization p...