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To improve the accuracy of radar rainfall estimates, this study examines rainfall relationships derived from polarimetric variables calculated from Drop Size Distributions (DSDs) measured by POSS (Precipitation Occurrence Sensor System) and PARSIVEL (PARticle Size and VELocity) disdrometers for eight different rainfall events in Korea associated with the Changma front, low pressure systems, typhoons, or the indirect effects of typhoons. Analysis of the correlation coefficients between polarimetric variables as independent parameters shows that multicollinearity is expected for Z–K DP , Z–A H , and K DP –A H . Of these, R(Z, K DP ) is the only relationship that had too low an accuracy for application to radar rainfall estimation. R(Z, Z DR , K DP ) and R(Z, K DP , A H ) were also omitted from this analysis because their intercept coefficients were too large. Analysis of the sensitivity of radar rainfall estimation to DSDs variation shows that the latest observed DSDs perform well, as much as 2.4 mm h −1 for RMSE (Root Mean Square Error) and 0.23 for NE (Normalized Error) in maximum. The statistical scores of each radar rainfall estimator vary between different rainfall events. This paper examines a new approach to radar rainfall estimation that is similar to the ensemble technique widely used in numerical prediction models. The ensemble members were chosen based on the average and standard deviation of their RMSE and NE for eight rainfall events. Two different weighting schemes were applied to each ensemble and the members were weighted equally or, alternatively, weighted based on their statistical scores. The performance of eight ensemble sets was examined using four independent rainfall events. There is little difference in the accuracy of each ensemble with respect to the weighting scheme applied. An ensemble composed of R(Z,Z DR ), R(Z), and R(K DP ), all given an equal weighting, was the most accurate.

Most commercialized measuring machines for bevel gears have a four-axis structure plus a 3D scanning probe. Because these probes are highly efficient, a large number of high-precision gear grinding and complex machines now apply them to detect tooth surface contour error. Nevertheless, such probes are still too expensive to implement on a milling machine. This paper, therefore, proposes a quasi-3D probe as a better solution for cost reduction. More specifically, the study develops an on-machine measurement system on five-axis machines which are needed for producing bevel gears. It employs a quasi-3D scanning probe whose sensor can detect in xyz directions while outputting only a one-dimensional (1D) deviation. This novel method enables measurement using solely a four-axis movement, meaning that only four coordinates are needed to measure pitch and topography. These coordinates are derived by first establishing mathematical models of bevel gear measurement. Also developed is an evaluation program t...

Raindrop size distribution (DSD) characteristics within the complex area of Busan, Republic of Korea (35.12° N, 129.10° E), were studied using a Precipitation Occurrence Sensor System (POSS) disdrometer over a 4-year period from 24 February 2001 to 24 December 2004. Also, to find the dominant characteristics of polarized radar parameters, which are differential radar reflectivity (Zdr), specific differential phase (Kdp) and specific attenuation (Ah), T-matrix scattering simulation was applied in the present study. To analyze the climatological DSD characteristics in more detail, the entire period of recorded rainfall was divided into 10 categories not only covering different temporal and spatial scales, but also different rainfall types. When only convective rainfall was considered, mean values of mass-weighted mean diameter (Dm) and normalized number concentration (Nw) values for all these categories converged around a maritime cluster, except for rainfall associated with typhoons. The convective rainfall of a typhoon showed much smaller Dm and larger Nw compared with the other rainfall categories. In terms of diurnal DSD variability, we analyzed maritime (continental) precipitation during the daytime (DT) (nighttime, NT), which likely results from sea (land) wind identified through wind direction analysis. These features also appeared in the seasonal diurnal distribution. The DT and NT probability density function (PDF) during the summer was similar to the PDF of the entire study period. However, the DT and NT PDF during the winter season displayed an inverse distribution due to seasonal differences in wind direction.

The rainy season from June to July in the East Asia is called as the Changma in Korea, the Meiyu in China, or the Baiu in Japan. The mesoscale convective systems which occur near a front frequently lead to severe weather phenomenon such as localized gust and heavy rainfall. An intensive field experiment was conducted at Chujado (33.95° N, 126.28° E) to characterize the precipitating system and the size distribution during a Changma period between 21 June 2007 and 11 July 2007. The precipitation system caused heavy rainfalls in Chujado for 20 h and three identified rainfall cases were analyzed using the Doppler radar data, disdrometer data, NCEP/NCAR reanalysis data, and sounding data Based on the radar reflectivity at Chujado, each rainfall system maintained for 7 h, 4 h, and 9 h, respectively. The analysis with the total vertical wind shear (TVWS) and the directional vertical wind shear (DVWS) shows that the temperature gradient was the strongest near the surface. Both warm and cold advections were occurred in all cases. The deep warm advection turns out to cause the longer rainfall lifetime and stronger rainrate but smaller raindrop size. The unstable atmospheric condition, which has cold advection at the surface and warm advection in higher level, causes the larger size diameter of raindrop.

A hepatocyte line was established from the liver of white-spotted spinefoot Siganus canaliculatus to study the biosynthesis of long-chain polyunsaturated fatty acids (LC-PUFA). The cells from the line, designated S. canaliculatus hepatocyte line (SCHL), grew and multiplied well in Dulbecco's modified Eagle's medium (DMEM)-F12 medium supplemented with 20 mM 4-(2-hydroxyethyl) piperazine-1-ethanesulphonic acid (HEPES), 10% foetal bovine serum (FBS) and 0·5% rainbow trout Oncorhychus mykiss serum at 28° C, showing an epithelial-like morphology and the normal chromosome number of 48 (2n) and have been subcultured for over 60 passages. The identity of the hepatocytes was confirmed by periodic acid Schiff (PAS) staining. The mRNA expression of all genes encoding the key enzymes for LC-PUFA biosynthesis including two desaturases (Δ4 Fad and Δ6-Δ5 Fad) and two elongases (Elovl4 and Elovl5), were detected in all cells from passages 5 to 60 and their expression levels became stable after passage 35 and showed responses to various PUFA incubation. This is similar to the situation determined in the liver of S. canaliculatus that were fed diets containing different fatty acids. These results indicated that SCHL was successfully established and can provide an in vitro tool to investigate lipid metabolism and regulatory mechanisms of LC-PUFA biosynthesis in teleosts, especially marine species.

To understand the different environment and morphology for heavy rainfall during 9–10 July 2007, over the Korean Peninsula, mesoscale convective systems (MCSs) that accompanied the Changma front in two different regions were investigated. The sub-synoptic conditions were analysed using mesoscale analysis data (MANAL), reanalysis data, weather charts and Multi-functional Transport Satellite (MTSAT-IR) data. Dual-Doppler radar observations were used to analyse the wind fields within the precipitation systems. During both the case periods, the surface low-pressure field intensified and moved northeastward along the Changma front. A low-level warm front gradually formed with an east-west orientation, and the cold front near the low pressure was aligned from northeast to southwest. The northern convective systems (meso-α-scale) were embedded within an area of stratiform cloud north of the warm front. The development of low-level pressure resulted in horizontal and vertical wind shear due to cyclonic circulation. The wind direction was apparently different across the warm front. In addition, the southeasterly flow (below 4 km) played an important role in generating new convective cells behind the prevailing convective cell. Each isolated southern convective cell (meso-β-scale) moved along the line ahead of the cold front within the prefrontal warm sector. These convective cells developed when a strong southwesterly low-level jet (LLJ) intensified and moisture was deeply advected into the sloping frontal zone. A high equivalent potential temperature region transported warm moist air in a strong southwesterly flow, where the convectively unstable air led to updraft and downdraft with a strong reflectivity core.

The rainy season from June to July in the East Asia is called the Changma in Korea, the Meiyu in China, or the Baiu in Japan. The mesoscale convective systems which occur near a front frequently lead to severe weather phenomenon such as localized gust and heavy rainfall. An intensive field experiment was conducted at Chujado (33.95°N, 126.28°E) to find out the characteristics of the precipitating system using information such as the raindrop size distribution, kinematic features during a Changma period between June 21 2007 and July 11 2007. Different characteristics of three identified rainfall cases in a Changma frontal precipitation system occurred from 5 to 6 July in 2007 at Chujado area have been identified. Based on the radar reflectivity and raingage at Chujado, each rainfall system maintained for 7 hours, 4 hours, and 9 hours, respectively. According to the analysis of a total vertical wind shear (TVWS) and a directional vertical wind shear (DVWS), the temperature gradient was the strongest near the surface and both warm and cold advections were occurred in all cases but at different levels. The deep warm advection was related to the longer rainfall lifetime and stronger rainrate, but smaller raindrop size. The unstable atmospheric condition, which has cold advection at the surface and warm advection in higher level, caused the larger size diameter of raindrop. The echo top height of 30 dBZ was around 6 km in the two rainfall systems and around 4 km in the other one. The number concentrations of raindrop has turning point at the drop size of 2 mm in diameter. The stronger (weaker) updraft and downdraft were also related to the decreased number concentration of smaller (larger) size drops and increased that of the larger (smaller) drops.

Raindrop size distribution (DSD) characteristics within the complex area of Busan, Korea (35.12° N, 129.10° E) were studied using a Precipitation Occurrence Sensor System (POSS) disdrometer over a four-year period from 24 February 2001 to 24 December 2004. Average DSD parameters in Busan, a mid-latitude site, were compared with corresponding parameters recorded in the high-latitude site of Järvenpää, Finland. Mean values of median drop diameter (D0) and the shape parameter (μ) in Busan are smaller than those in Järvenpää, whereas the mean normalized intercept parameter (Nw) and rainfall rate (R) are higher in Busan. To analyze the climatological DSD characteristics in more detail, the entire period of recorded rainfall was divided into 10 categories with different temporal and spatial scales. When only convective rainfall was considered, mean Dm and Nw values for all these categories converged around a maritime cluster, except for rainfall associated with typhoons. The convective rainfall of a typhoon showed much smaller Dm and larger Nw compared with the other rainfall categories. In terms of diurnal DSD variability, we observe maritime (continental) precipitation during the daytime (DT) (nighttime, NT), which likely results from sea (land) breeze identified through wind direction analysis. These features also appeared in the seasonal diurnal distribution. The DT and NT Probability Density Function (PDF) during the summer was similar to the PDF of the entire study period. However, the DT and NT PDF during the winter season displayed an inverse distribution due to seasonal differences in wind direction.

In magnetic multilayer systems, a large spin-orbit coupling at the interface between heavy metals and ferromagnets can lead to intriguing phenomena such as the perpendicular magnetic anisotropy, the spin Hall effect, the Rashba effect, and especially the interfacial Dzyaloshinskii–Moriya (IDM) interaction. This interfacial nature of the IDM interaction has been recently revisited because of its scientific and technological potential. Here we demonstrate an experimental technique to straightforwardly observe the IDM interaction, namely Brillouin light scattering. The non-reciprocal spin wave dispersions, systematically measured by Brillouin light scattering, allow not only the determination of the IDM energy densities beyond the regime of perpendicular magnetization but also the revelation of the inverse proportionality with the thickness of the magnetic layer, which is a clear signature of the interfacial nature. Altogether, our experimental and theoretical approaches involving double time Green's function methods open up possibilities for exploring magnetic hybrid structures for engineering the IDM interaction., Spin-orbit effects at heavy metal/ferromagnet interfaces can give rise to the Dzyaloshinskii-Moriya interaction, promoting chiral magnetization textures applicable in thin film devices. Here, the authors use Brillouin light scattering to study the dependence of this interaction on film thickness.

The optical properties of the populated ZnCdSe/ZnSe quantum dots have been studied by photoluminescence spectra measured with different laser excitation apertures at temperatures from 22 to 300 K. The differences of spectral features between small and large excitation spot suggest the existence of quantum dot size fluctuation in the system. The temperature evolution of photoluminescence spectral features revealed that two types of quantum dots with different densities and sizes coexist in ZnCdSe/ZnSe system. The energy spacings of the two kinds of quantum dot emissions are about 50 meV at various temperatures. The thermally activated lateral transfer processes of carriers populated in the two sorts of quantum dots are investigated by temperature dependences of spectral intensities.

We studied the potentiation effect of cholecystokinin-octapeptide and secretin on pancreatic secretion of bicarbonate and trypsin in humans. The pancreatic bicarbonate and trypsin outputs were determined by using a triple-lumen duodenal tube and indicator dilution technique while gastric juice was completely aspirated. When cholecystokinin-octapeptide in varied doses, 2.6, 5.3, 10.9, 26.3, 52.6, and 109.4 pmol . kg-1 . h-1, was added to i.v. infusion of secretin in a physiologic dose, 0.03 clinical units (CU) . kg-1 . h-1, the bicarbonate outputs were significantly greater than those achieved by secretin or cholecystokinin-octapeptide alone or the sum of the bicarbonate outputs produced by each hormone. The potentiation effect of cholecystokinin-octapeptide occurred at the dose of 10.9 pmol . kg-1 . h-1. No further further augmentation on the bicarbonate output occurred when the dose of cholecystokinin-octapeptide was increased in the dose range greater than 10.9 pmol . mg-1 . h-1. No potentiation on pancreatic secretion of trypsin was apparent when the two hormones were given simultaneously. Thus, cholecystokinin-octapeptide in a relatively small dose range potentiated the pancreatic bicarbonate secretion stimulated by a physiologic dose of secretin. The pancreatic enzyme secretion does not appear to be potentiated by two hormones.

Using two groups of volunteers, we investigated the effects of atropine on pancreatic secretion of bicarbonate, protein, and trypsin stimulated by secretin. Secretin given intravenously in graded doses of 0.03, 0.06, and 0.125 clinical units.kg-1.h-1 produced significant increases in pancreatic secretion of bicarbonate in a dose-related manner. Pancreatic secretion of bicarbonate and protein was significantly suppressed by intravenous atropine, despite the dose of secretin infused. Intrajejunal perfusion of HCl at a rate of 3.3 mM/h, producing plasma secretin concentration comparable with that of the postprandial state, resulted in significant increases in the pancreatic secretion of bicarbonate. The increase in the pancreatic secretion of bicarbonate and trypsin was significantly suppressed by atropine. However, atropine did not affect the increase in the plasma secretin concentration produced by jejunal acidification or intravenous secretin. These studies indicate that atropine inhibits the pancreatic effect but not the intestinal release of secretin.

A method of recording gastric myoelectric activity with a peroral suction electrode was evaluated, and the recording was compared with that obtained by implanted electrodes on the serosal surface of the stomach of laparotomized humans. In a group of patients with unexplained nausea, epigastric bloating, and vomiting, abnormal antral myoelectric activities were found by a peroral electrode, in contrast to a regular pacesetter potential (frequency: 3-4/min) in control subjects. These abnormalities were confirmed by the recordings from the implanted electrodes in the same subjects. The study indicates that peroral recording of gastric myoelectric activity is a useful diagnostic method for the detection of gastric myoelectric activity abnormalities in humans.

The relationship between electric and mechanical activities of the gastric antrum was investigated in both humans and dogs. In 2 patients, in whom platinum monopolar electrodes were implanted on the serosal surface of the antrum and a perfused manometric tube was placed in the stomach, the number of gastric contractions detected by manometry was only less than 50% of the pacesetter potentials accompanied by action potentials or second potentials. No contraction of the stomach was recorded by manometry when pacesetter potentials occurred without action potentials or second potentials. The relationship was further investigated in 11 anesthetized dogs prepared with implanted electrodes and sensitive ministrain gauges implanted on the serosal surface of the stomach and an intragastric manometric tube. In these dogs, phasic contractions were always recorded by the method using ministrain gauges although the electrical activity showed only PSPs without action potentials or second potentials. The manometry, however, could not recognize these phasic contractions. When the stomach was stimulated by bethanechol infusion through the splenic artery, as in the human stomach, the manometry detected less than 50% of gastric contractions detected by the strain gauge recording. The gastric dysrhythmia including tachygastria, tachyarrhythmia, and bradygastria was induced in 10 dogs by epinephrine, 100 micrograms X kg-1 X h-1, infused via the splenic artery. During the period of gastric dysrhythmia, the phasic contractions disappeared and no contraction associated with action potential could be observed. The phasic contractions reappeared as long as the PSPs occurred regularly in a frequency of 4-5 cycles/min during either the control period or during the period of epinephrine infusion. The epinephrine-induced gastric dysrhythmia was blocked or reversed to normal pacesetter potentials by intraarterial infusion of phentolamine. Our study suggests the following: (1) the pacesetter potentials not only pace and direct gastric contraction, but they may also play a role in the genesis of phasic contractions of the stomach, and (2) gastric contractions detected by sensitive strain gauges are not always recorded by the intraluminal manometry and, thus, gastric dysrhythmia may not be detected by the manometry in humans.