Abstract. Convective gravity wave (GW) sources are spatially localized and emit at the same time waves with a wide spectrum of phase speeds. Any wave analysis therefore compromises between spectral and spatial resolution. Future satellite borne limb imagers will for a first time provide real 3-D volumes of observations. These volumes will be however limited which will impose further constraints on the analysis technique. In this study a three dimensional fewwave approach fitting sinusoidal waves to limited 3-D volumes is introduced. The method is applied to simulated GWs above typhoon Ewiniar and GW momentum flux is estimated from temperature fluctuations. Phase speed spectra as well as average profiles of positive, negative and net momentum fluxes are compared to momentum flux estimated by Fourier transform as well as spatial averaging of wind fluctuations. The results agree within 10-20 %. The few-wave method can also reveal the spatial orientation of the GWs with respect to the source. The relevance of the results for different types of measurements as well as its applicability to model data is discussed.

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The presented study highlights the feasibility and accuracy of novel computational methods based on a morphological filter and a least square acceleration filter to detect step events for evaluating normal and pathological gait parameters using a single accelerometer. This is the first evidence that demonstrates the feasibility and accuracy of the novel accelerometer-based system and methods in both normal and pathological populations.

Prenatally detected congenital orbital teratomaA 26-year-old Korean primigravida was referred to our hospital at 17 weeks' gestation for evaluation of a fetal brain mass. Transabdominal ultrasound imaging showed a 3.0 × 1.6-cm solid cystic mass with internal complex echogenicity in the infratentorial region of the left eyeball (Figure 1). Fetal biometry and the amniotic fluid

Abstract. For a case study of Typhoon Ewiniar performed with a mesoscale model, we compare stratospheric gravity wave (GW) momentum flux determined from temperature variances by applying GW polarization relations and by assuming upward propagating waves, with GW momentum flux calculated from model winds which is considered as a reference. The temperature-based momentum-flux profile exhibits positive biases relative to the reference, which fluctuate significantly with altitude. The vertically-averaged magnitude of the positive biases is about 14 % of the reference momentum flux. We found that this deviation from the reference stems from the interference between upward and downward propagating waves. The downward propagating GWs are due mainly to partial reflections of upward propagating waves at altitudes where the background wind and stability change with height. When the upward and downward propagating waves are decomposed and their momentum fluxes are calculated separately from temperature perturbations, the fraction of the momentum flux arising from the downward propagating waves is about 4.5-8.2 % of that from the upward propagating waves. The net momentum flux of upward and downward propagating GWs agrees well with the reference from the model wind perturbations. The implications of this study for the GW momentum-flux observations from satellites are discussed.