On the determination of the North galactic Pole from Cepheid variables.

1952 ◽  
Vol 56 ◽  
pp. 204 ◽  
Author(s):  
J. Ashbrook ◽  
R. L. Duncombe
1987 ◽  
Vol 117 ◽  
pp. 37-37
Author(s):  
W.L.H. Shuter ◽  
W. N. Stocker

The line-of-sight velocity field has been determined for all 80 FV stars within 15 degrees of the North Galactic Pole (NGP) with measured and constant velocities, and measured distances, from the catalogs of Hill et al. (1976, 1982). These data are a subset of the data used in a determination of Kz by Bahcall (1984). Procedures were as described by Goulet and Shuter (1984). The velocity field is depicted in Figure 1, and the magnitude of the velocity residuals is plotted in Figure 2.


1977 ◽  
Vol 4 (2) ◽  
pp. 75-76
Author(s):  
A. R. Upgren

Recently Dessureau and Upgren (1975) redetermined the velocity distribution of giant stars in the north galactic pole direction using Upgren’s (1962) catalogue and Oort’s (1960) determination of K(z). The velocities were assumed to be represented by n Gaussian distributions with no further constraints imposed. The velocities are well represented by three such distributions whose properties disagree with those found by Oort. A larger number did not improve the stability of the solution. Without radial velocities, however, they could not redetermine the K(z) force itself.


1985 ◽  
Vol 106 ◽  
pp. 153-160
Author(s):  
Bengt Strömgren

The approach by Bahcall and Soneira to the determination of galactic parameters through the use of star counts is referred to, and tests of the Bahcall-Soneira Galaxy model based on additional observational data are discussed.The determination of the local mass density by Hill, Hilditch and Barnes through studies of A and F stars in the region of the North Galactic Pole is briefly discussed, as is a recent investigation of the problem by Bahcall.In the determination of the galactic force Kz and the local mass density from the density distribution ν(z) and the distribution f(W) of velocities at right angles to the galactic plane for a group of tracer stars, it is important to secure homogeneity of the tracer group. This has led Hill, Hilditch and Barnes in a continuation of their investigation to use photoelectric uvby photometry to segregate homogeneous groups of F stars. A similar approach is followed by Danish astronomers, whose work is briefly described.


Author(s):  
Peter M. Fischer ◽  
Patrik Klingborg ◽  
Fanny Kärfve ◽  
Fredrika Kärfve ◽  
C. Hagberg ◽  
...  

Determination of the complete occupational sequence of the site, including investigation of pre-12th century levels which were thoroughly studied by P. Åström since the 1970s, is the main task of the planned project. During the course of the expedition (NSCE11) in spring 2010 a ground-penetrating radar survey (GPR) was carried out at Dromolaxia Vizatzia/Hala Sultan Tekke in Area 6, leading to the discovery of a large Late Cypriote complex. The compound is bordered to the north by a substantial wall, against which nine rooms (so far) could be exposed. Two occupational phases have been verified but there are indications of a third. The suggested functions of the various structures of the most recent phase are: living, working, storage and administration spaces. The rich find contexts point to the production of textiles and metal objects, and the locally produced pottery is generally of a high quality. There are also many imports, mainly from the Mycenaean sphere of culture. The locally produced vessels from Phase 2 include the “Creature krater” which is a masterpiece of a high artistic standard. Another piece of elevated artistry is the piece of a “Warrior vase”.


2020 ◽  
Vol 63 (3) ◽  
pp. 283-298
Author(s):  
Nuno Nunes ◽  
Sofia Valente ◽  
Sónia Ferraz ◽  
Maria Carmo Barreto ◽  
Miguel A.A. Pinheiro de Carvalho

AbstractFifteen attached macroalgae from the Madeira Archipelago, comprising three green, three red and nine brown algal species, as well as two beach-cast macroalgal samples, collected along the north shore of Gran Canaria, were assessed for their biochemical properties. The analysis included the determination of total minerals, total carbohydrates, protein, lipids, chlorophyll a, total carotenoids, total phenolic content, fucoxanthin and phycobilins (allophycocyanin, phycocyanin and phycoerythrin). The results showed a high variability of biochemical composition, allowing for the targetting of specific bioresources for particular purposes, including functional foods. This work provides the foundation for a biorefinery strategy implementation plan, for which specific macroalgae may be targeted for valuable and beneficial compounds.


2020 ◽  
pp. 1-14
Author(s):  
Richard D. Ray ◽  
Kristine M. Larson ◽  
Bruce J. Haines

Abstract New determinations of ocean tides are extracted from high-rate Global Positioning System (GPS) solutions at nine stations sitting on the Ross Ice Shelf. Five are multi-year time series. Three older time series are only 2–3 weeks long. These are not ideal, but they are still useful because they provide the only in situ tide observations in that sector of the ice shelf. The long tide-gauge observations from Scott Base and Cape Roberts are also reanalysed. They allow determination of some previously neglected tidal phenomena in this region, such as third-degree tides, and they provide context for analysis of the shorter datasets. The semidiurnal tides are small at all sites, yet M2 undergoes a clear seasonal cycle, which was first noted by Sir George Darwin while studying measurements from the Discovery expedition. Darwin saw a much larger modulation than we observe, and we consider possible explanations - instrumental or climatic - for this difference.


2021 ◽  
Vol 10 (1) ◽  
pp. 27
Author(s):  
Bilal Ahmad Munir ◽  
Sajid Rashid Ahmad ◽  
Raja Rehan

In this study, a relation-based dam suitability analysis (RDSA) technique is developed to identify the most suitable sites for dams. The methodology focused on a group of the most important parameters/indicators (stream order, terrain roughness index, slope, multiresolution valley bottom flatness index, closed depression, valley depth, and downslope gradient difference) and their relation to the dam wall and reservoir suitability. Quantitative assessment results in an elevation-area-capacity (EAC) curve substantiating the capacity determination of selected sites. The methodology also incorporates the estimation of soil erosion (SE) using the Revised Universal Soil Loss Equation (RUSLE) model and sediment yield at the selected dam sites. The RDSA technique identifies two suitable dam sites (A and B) with a maximum collective capacity of approximately 1202 million m3. The RDSA technique was validated with the existing dam, Gomal-Zam, in the north of Sanghar catchment, where RDSA classified the Gomal-Zam Dam in a very high suitability class. The SE estimates show an average of 75 t-ha−1y−1 of soil loss occurs in the study area. The result shows approximately 298,073 and 318,000 tons of annual average sediment yield (SY) will feed the dam A and B respectively. The SE-based sediment yield substantiates the approximate life of Dam-A and Dam-B to be 87 and 90 years, respectively. The approach is dynamic and can be applied for any other location globally for dam site selection and SE estimation.


2018 ◽  
Vol 229 ◽  
pp. 02021
Author(s):  
James Mwangi ◽  
Laura Putri ◽  
Listhbeth Collins

With over 50 million students, Indonesia has the fourth largest education system in the world. The first twelve years of education are compulsory for all citizens. The students, together with over 3 million teachers spend six (or five in some cases) days a week at over 300,000 schools, typically from 6:30 AM to 2 (or 3) PM. Geographically, Indonesia is traversed by the infamous “ring of fire” and prone to natural events resulting from the tectonic plate movements of the Australian Plate from the South, the Eurasian and Sunda Plates from the North and the Philippine Plate from the East. Left unmitigated, these natural events would lead to natural disasters emanating from resulting earthquakes and leading to tsunamis, landslides, the collapse of building structures and failure of lifelines (roads, pipelines, electrical grid, etc.). In an effort to provide disaster-safe schools, the National Agency for Disaster Management has required that school facilities be a community center in case of disasters and serve as emergency shelters. Retrofit of existing buildings will be needed to comply with government guidelines. This paper presents a case study of the determination of structural deficiencies of an existing school building in SDN 42 Korong Gadang, Padang, West Sumatra and implementation of a seismic retrofit (design and construction) at the same building to mitigate potential earthquake disaster.


2020 ◽  
Vol 15 (4) ◽  
pp. 613-619
Author(s):  
Li Kong ◽  
Yunpeng Zhang ◽  
Zhijian Lin ◽  
Zhongzhu Qiu ◽  
Chunying Li ◽  
...  

Abstract The present work aimed to select the optimum solar tracking mode for parabolic trough concentrating collectors using numerical simulation. The current work involved: (1) the calculation of daily solar radiation on the Earth’s surface, (2) the comparison of annual direct solar radiation received under different tracking modes and (3) the determination of optimum tilt angle for the north-south tilt tracking mode. It was found that the order of solar radiation received in Shanghai under the available tracking modes was: dual-axis tracking > north-south Earth’s axis tracking > north-south tilt tracking (β = 15°) > north-south tilt tracking (β = 45) > north-south horizontal tracking > east-west horizontal tracking. Single-axis solar tracking modes feature simple structures and low cost. This study also found that the solar radiation received under the north-south tilt tracking mode was higher than that of the north-south Earth’s axis tracking mode in 7 out of 12 months. Therefore, the north-south tilt tracking mode was studied separately to determine the corresponding optimum tilt angles in Haikou, Lhasa, Shanghai, Beijing and Hohhot, respectively, which were shown as follows: 18.81°, 27.29°, 28.67°, 36.21° and 37.97°.


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