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In the pairwise rigid registration problem, we need to find a rigid transformation that aligns two point clouds. The classical and most common solution is the Iterative Closest Point (ICP) algorithm. However, the ICP and many of its variants require that the point clouds are already coarsely aligned. We present in this paper a method named Shape-based Weighting Covariance Iterative Closest Point (SWC-ICP) which improves the possibility to correctly align two point clouds, regardless of the initial pose, even when they are only partially overlapped, or in the presence of noise and outliers. It benefits from the local geometry of the points, encoded in second-order orientation tensors, to provide a second correspondences set to the ICP. The cross-covariance matrix computed from this set is combined with the usual cross-covariance matrix, following a heuristic strategy. In order to compare our method with some recent approaches, we present a detailed evaluation protocol to rigid registration. Results show that the SWC-ICP is among the best compared methods, with a better performance in situations of wide angular displacement of noisy point clouds. [ABSTRACT FROM AUTHOR]

Fine-grained sediment budgets based on the monthly bed level and net sediment flux monitoring from October 2006 to October 2007 are estimated to examine the relative contributions of tides and river discharge to mud transport on an intertidal flat adjacent to a river mouth in a semiclosed sound. The estimated sediment budgets are interpreted using the water mass balance equation and the horizontal tidal current pattern measured using high frequency (HF) radar. The intertidal flat accreted during normal discharge conditions are primarily attributable to the alongshore sediment flux toward the river mouth. However, the flat was eroded when the large offshore suspended sediment transport occurred on the flat during the large river discharge. The net alongshore tidal current causes alongshore sediment fluxes toward the river mouth on this intertidal flat adjacent to the river mouth. These findings may be specific to this site, but an adopted comprehensive approach may be applicable to other sites. [ABSTRACT FROM AUTHOR]

Abstract: is composed of spin dimers and has a gapped singlet ground state. This system undergoes antiferromagnetic orderings under both external magnetic field and hydrostatic pressure, which are described as Bose–Einstein condensation and softening of triplet excitations. An overview of the magnetic quantum phase transitions in is given. [Copyright &y& Elsevier]

Determines rock permeability. Measurement of permeability as a method of detecting structural looseness of rock mass; Occurrence of loosening due to excavation of different types or to long term deterioration of the surrounding ground due to natural processes; Demonstration of the practicality of the method.

Abstract: Magnetization measurements were performed on with gapped ground state. The critical density and the magnetic phase diagram were obtained. The interacting constant was obtained as . The experimental phase boundary for agrees perfectly with the magnon BEC theory based on the Hartree–Fock approximation with realistic dispersion relations and . The exponent obtained with all the data points for is , which is somewhat larger than theoretical exponent . However, it was found that the exponent converges at with decreasing fitting window. [Copyright &y& Elsevier]

Abstract: It is important to assess long-term alteration of engineered barrier composed of bentonite and cement for the safety assessment of radioactive waste disposal. A mineral model for bentonite–cement–seawater systems and a hydraulic conductivity model for bentonite buffer materials were developed and verified by comparing results of the model calculations with experimental observations. Changes in mineralogy of bentonite buffer materials and accompanying changes in the hydraulic conductivity over 10,000y were calculated to identify key issues in the long-term alteration analysis. The calculation showed that the temperature, the slow kinetics of the dissolution of montmorillonite, the diffusive mass transfer and the initial (∼1000y) mineralogical changes were identified as the key issues. The salinity of the groundwater was identifies as another key issue, which has both positive and negative effects on the hydraulic conductivity. [Copyright &y& Elsevier]

Yamada, F., Uehara, K., Hokamure, T. and Yamabe, T., 2007. Morphology and seasonal evolution of intertidal multiple sand bars in low wave environment. Journal of Coastal Research, SI 50 (Proceedings of the 9th International Coastal Symposium), 978 – 984. Gold Coast, Australia, ISSN 0749.0208 The morphology of intertidal multiple sand bars of Okoshiki Beach in Ariake Bay, Japan is examined to provide insight into the factors controlling the bar characteristics in the low wave environment. Cross-shore profiles of intertidal multiple sand bars were measured monthly for 2 years from July, 2003 to July, 2005. Each measured profile is separated into a mean profile and a bar geometry using quadratic polynomial fitting. Superimposed on the mild foreshore (1/250) are at least seven low height (0.1-0.6m) ridges with an average wavelength of 40 m. The sand bar morphology appears to be a permanent feature in both form and position. Probability density functions of bar height and length have indicated that their distributions can be approximated well using standard normal distributions. These results may suggest that the genesis of multiple sand bars has a different mechanism comparing to that of wave-generated ripples. The bars occur approximately between the mean high and low water levels during neap tides. This bar zone is related to the zone where the tidal shoreline velocity is largest in the cross-shore. [ABSTRACT FROM AUTHOR]

Summary: Previously, a single nucleotide polymorphism (SNP) related to gait type was identified at position 22 999 655 of chromosome 23 in the coding region of DMRT3 (DMRT3:Ser301Ter) by showing that a cytosine (C) to adenine (A) mutation of this SNP induced pace in the Icelandic horse. We investigated the effect of DMRT3:Ser301Ter on the gait of Hokkaido Native Horses, a Japanese native breed, and examined genetic factors other than DMRT3 by exploring genome‐wide SNPs related to gait determination. All animals exhibiting pace were AA for DMRT3:Ser301Ter, confirming the association of DMRT3:Ser301Ter with gait determination; however, 14.3% of the animals exhibiting trot also had AA for DMRT3:Ser301Ter, suggesting the presence of another factor(s) cooperatively working with DMRT3:Ser301Ter for gait determination. SNPs on chromosomes 13 and 23 were detected by genome‐wide association analysis (false discovery rate <0.05), although SNPs on chromosome 23 were all located in the vicinity of DMRT3:Ser301Ter, confirming the association with DMRT3. A genome‐wide association study targeting only animals with AA for DMRT3:Ser301Ter to examine genetic factors cooperatively working with DMRT3:Ser301Ter for gait determination suggested associations of 23 SNPs on six chromosomes. In a series of analyses of the effect of a maternal factor (dam's gait) on gait determination, the effect was suggested in comparison of the frequencies of exhibiting pace in gait checks in only two animal groups having dams with different DMRT3:Ser301Ter genotypes (P < 0.05), suggesting that the gait of the dam does not have a major effect on whether progeny homozygous for the DMRT3:Ser301Ter mutation will preferentially pace or trot. [ABSTRACT FROM AUTHOR]

The effect of through-thickness temperature gradients in thin films irradiated by short laser pulses is described, together with its application to direct overwrite. We found by simulation that through-thickness temperature gradients become substantial when a medium is irradiated by short laser pulses of the order of 1 ns which is the characteristic time of heat diffusivity. This effect qualitatively explains why in writing experiments on a double-layered medium short pulses expand the laser power range for a writing process. [ABSTRACT FROM AUTHOR]

Our ability to predict beach erosion above the still water level (SWL) is still not satisfactory due to the lack of adequate technology to accurately measure the sediment concentration and velocity in very shallow water, including the swash zone where the beach face is intermittently covered with water and exposed to the atmosphere. A simple procedure is proposed here to improve our predictive capability for the particular case of scarping erosion caused by wind-generated waves above the SWL. If the slope at the steep scarp is larger than the limiting slope of the internal sediment friction, the steep face is assumed to be eroded due to the computed offshore sediment transport at the toe of the scarp. The bedload and suspended sediment transport at the toe of the scarp was computed using a time-averaged model that includes the steep bottom slope effect. The model was validated against a novel experiment in a multidirectional wave basin, where scarping was reproduced. The water level was raised in four steps to reproduce the shoreface erosion, berm overwash and berm erosion, successively. Horizontal and tilted berms were tested against similar normal incident irregular waves to compare the performance of the profile without and with ponding, respectively. For the tilted case, ponding appeared when the tilted berm was overtopped. No ponding was observed for the horizontal berm test even when the berm was overtopped. The predictability was estimated using the Brier skill score (BSS). The predictability of the scarping was good (BSS ≥ 0.6) for the horizontal berm test and fair (BSS ≥ 0.4) for the tilted berm test. This decrease in the predictability may be related to the ponding, which is not included in the model. [ABSTRACT FROM AUTHOR]

The characteristic features of surgically curable mucin-producing extrahepatic bile duct carcinoma (MPEBC) have not previously been elucidated. Three (6.5%) of 46 patients who underwent surgery in our department for bile duct carcinoma between 1986 and 1997 had MPEBC. Clinicopathological features, diagnostic procedures and operative methods for patients with MPEBC were investigated. Tumors in the bile duct were identified by cholangioscopy combined with cholangiography after removal of mucin balls. Tumors were located close to the hepatic confluence in these patients. Two patients underwent hepatic lobectomy together with caudate lobectomy while the other underwent resection of the hepatic confluence. Absence of residual tumors was confirmed histologically in these patients. All three patients remain alive without evidence of recurrence, 22–54 months after surgery. MPEBC is a curable disease. Accurate localization in the biliary tree is essential and can only be obtained after, i) removal of mucin balls, and ii) extensive diagnostic work-up including cholangiography, cholangioscopy and intraoperative pathological examination. [ABSTRACT FROM AUTHOR]

A new environmental enrichment device, termed a "foraging/grooming board," was presented to 8 individually housed rhesus monkeys for the explicit purpose of reducing the level of aberrant behaviors manifested by these animals. The device consisting of a piece of plexiglass covered with artificial fleece, had particles of food treats rubbed into it and was attached to the outside of each animal's home cage. All animals foraged from the board to the point that a significant reduction in the level of abnormal behavior was noted. Most animals also groomed the fleece covering the board, utilizing the same motor patterns that would be directed toward grooming another monkey. These boards are inexpensive to construct and easy to sanitize, and do not require placing animal facility personnel at risk to maintain them. [ABSTRACT FROM AUTHOR]

By forming a micron-scale Schottky diode on a GaAs/n+–GaAs wafer with low density (∼4×108 cm−2) self-assembled InAs quantum dots (QDs) embedded in the top GaAs layer, we have studied resonant tunneling transport of electrons via single QDs. As the diode defined by electron-beam lithography and chemical etching has a size of about 1 μm2 and the edges of each diode are depleted, the number of active InAs QD contained in each microdiode can be reduced to less than unity in average. Current–voltage measurements were performed using conductive probe atomic force microscope, and current peaks caused by electrons resonantly tunneling through quantum levels of single QDs have been observed at temperatures as high as ∼130 K. [Copyright &y& Elsevier]