696 research outputs found
Optimal Design Methodology Emphasizing Surface Equipment Placement Applied to 6U CubeSats
In recent years, the number of launches of nano-satellites, which have the advantage of being developed in a short period of time, has increased rapidly. However, several issues need to be addressed to maximize the benefits of nano-satellites. One of them is that theoretical methods have not been widely applied to the placement of equipment on satellites. Therefore, this paper proposes an Optimal Design Methodology Emphasizing Surface Equipment Placement Applied to 6U CubeSats . It details the design and development of two 6U CubeSats using this method, along with the results and lessons learned
Spectroscopic Observation of the Interface States at the SiO<sub>2</sub>/4H-SiC(0001) Interface
We obtained the energy distribution of the interface states at the SiO2/4H-SiC(0001) interface using operando hard x-ray photoelectron spectroscopy. Two types of interface states were observed: one with continuous interface states in the entire SiC band-gap and the other with sharp interface states formed below the conduction band minimum (CBM). The continuous interface states in the whole gap were attributed to carbon clusters while the sharp interface states observed near the CBM were due to the Si2—C=O state and/or the Si2—C=C—Si2 state at the SiO2/SiC interface
A comparison of dust concentration with high resolution analysis and visible strata in the Holocene and Last Glacial Maximum periods from the Dome Fuji ice core, East Antarctica
第3回極域科学シンポジウム 横断セッション「海・陸・氷床から探る後期新生代の南極寒冷圏環境変動」11月26日(月)、27日(火) 2階ラウン
Mitigating the impact of fiber assignment on clustering measurements from deep galaxy redshift surveys
We examine the impact of fiber assignment on clustering measurements from
fiber-fed spectroscopic galaxy surveys. We identify new effects which were
absent in previous, relatively shallow galaxy surveys such as Baryon
Oscillation Spectroscopic Survey . Specifically, we consider deep surveys
covering a wide redshift range from z=0.6 to z=2.4, as in the Subaru Prime
Focus Spectrograph survey. Such surveys will have more target galaxies than we
can place fibers on. This leads to two effects. First, it eliminates
fluctuations with wavelengths longer than the size of the field of view, as the
number of observed galaxies per field is nearly fixed to the number of
available fibers. We find that we can recover the long-wavelength fluctuation
by weighting galaxies in each field by the number of target galaxies. Second,
it makes the preferential selection of galaxies in under-dense regions. We
mitigate this effect by weighting galaxies using the so-called individual
inverse probability. Correcting these two effects, we recover the underlying
correlation function at better than 1 percent accuracy on scales greater than
10 Mpc/h.Comment: 17 pages, 11 figure
NASA ExoPAG Study Analysis Group 11: Preparing for the WFIRST Microlensing Survey
NASA's proposed WFIRST-AFTA mission will discover thousands of exoplanets
with separations from the habitable zone out to unbound planets, using the
technique of gravitational microlensing. The Study Analysis Group 11 of the
NASA Exoplanet Program Analysis Group was convened to explore scientific
programs that can be undertaken now, and in the years leading up to WFIRST's
launch, in order to maximize the mission's scientific return and to reduce
technical and scientific risk. This report presents those findings, which
include suggested precursor Hubble Space Telescope observations, a
ground-based, NIR microlensing survey, and other programs to develop and deepen
community scientific expertise prior to the mission.Comment: 35 pages, 5 Figures. A brief overview of the findings is presented in
the Executive Summary (2 pages
Computed tomography findings of intersigmoid hernia
Purpose: To evaluate the computed tomography findings of intersigmoid hernias. Material and methods: Between April 2010 and March 2018, 7 patients who were surgically diagnosed with intersigmoid hernia in 3 institutions were enrolled in this study. Two radiologists evaluated imaging findings for the herniated small bowel, the distance between the occlusion point and bifurcation of the left common iliac artery, and the anatomic relationship with adjacent organs. Results: All patients were male, and their mean age (standard deviation, range) was 61.0 (13.5, 36-85) years. The mean size of the bowel loops was 5.2 (1.3, 4.0-8.3) cm in the caudal direction, 3.6 (0.8, 2.5-5.1) cm in the lateral, and 3.4 (0.6, 2.5-4.7) cm in the anterior-posterior direction. The volume was 37.9 (27.8, 15.6-103.0) cm3 approximated by an ellipse, and 24.0 (17.7, 9.9-65.6) cm3 approximated by a truncated cone. The obstruction point was located 3.6 (0.6, 2.8-4.7) cm inferior to the bifurcation of the left common iliac artery. In all cases, the small bowel ran under the point at which the inferior mesenteric vessels bifurcated to the superior rectal vessels and the sigmoid vessels and formed a sac-like appearance between the left psoas muscle and the sigmoid colon. The ureter ran dorsal to the point of the bowel stenosis, and the left gonadal vein ran outside the small bowel loops. Conclusions: All cases showed common imaging findings, which may be characteristic of men's intersigmoid hernia. In addition, the fossa's position was lower, and the size was larger than in the previous study, which may be a risk factor
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