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A survey of rich galaxy clusters, redshifts for many of those clusters, and galaxy counts by eye to B - 19.0 show the Indus Supercluster to be an annular (in projection) configuration of nine rich clusters at 0.073 < z 4~0.080 apparently connected by bridges of galaxies. Photoelectrically calibrated photographic photometry of galaxy images on six U.K. Schmidt plates using the COSMOS machine at the Royal Observatory, Edinburgh, gave photometric information for about 150,000 galaxies. From this, the luminosity function of the Indus Supercluster was extracted. To B - 21.5, the Supercluster includes about 25,000 galaxies, its estimated total luminosity is 7 x 1019 Lo, and - if its mass-to-light ratio is typical - its total mass is ti 1 x 10'691 . Its diameter is about 40 Mpc. These parameters make it similar to other known superclusters. In addition, the integrated apparent field luminosity function for galaxies, derived from the 140 square degrees of sky scanned on Schmidt plates by COSMOS, agrees with most previous determinations. The general picture of a sponge-like cellular distribution of galaxies as developed by Einasto and his colleagues is confirmed. Though there are some indications that this structure is primordial, neither data nor theories are yet sufficient to allow an adequate explanation of the development of such structure in the universe.

Abstract: Geological uncertainty is a major source of risk in resource projects and must be characterized. Extensive research has been undertaken in the development of sophisticated techniques given the economic impact of this uncertainty. The Hierarchical Truncated PluriGaussian (HTPG) simulation is well‑known among existing categorical modeling techniques for its ability to portray realistic features. HTPG uses latent Gaussian variables to simulate categories. The rules to map continuous variables to categories, and to introduce juxtaposition constraints are key and known as truncation trees. The number of truncation trees is large, and their structures are very flexible, however, choosing the correct one is a daunting task. This work focuses on developing tools to choose the truncation tree that leads to the optimal model. The process starts with the inference of possible trees from any source of limited data including drillholes, point samples, or images. Then, a tree is chosen based on measures of goodness. This research has made several contributions. First, it presented tools to enumerate all possible trees in friendly plots given the number of categories. Second, it introduced interval probabilities to quantify the geometrical associations of categories and proposed a dissimilarity matrix based on this concept to summarize the associations and to be used in inference algorithms. Third, it implemented Single Linkage Cluster Analysis (SLCA), and spectral partitioning from graph theory for the inference of trees. Lastly, it showed an optimization framework in a synthetic example that used all trees to recommend transition probabilities as an appropriate measure of goodness. The tools and methodologies were used in a case study where the chosen tree obtained good metrics and respected the geological understanding.

The problem of this study is the development of a model curriculum for high school metallurgy students. The study was made at the Skyline Career Development Center of the Dallas Independent School District, Dallas, Texas. The study has three purposes. In addition to providing a model curriculum for high school metallurgy students, a second purpose is to describe the developmental processes by which the curriculum was derived. The third purpose is the evaluation of the basis of the content of the model curriculum. It was found that of the 76 concept-relationships stated, 64 were true as originally written according to the established rating criteria. It was also found that 64 of the 76 concept relationships stated were appropriate for understanding by high school students, although the two lists of 64 concepts were not identical. The unapproved concept statements were deleted or rewritten according to the established criteria. Only one of the 33 skills listed received a low rating. It was further found from a report of the metallurgy instructor that the 21 high school students in the metallurgy program had attempted a cumulative total of 374 of the 33 behavioral objectives in the curriculum and had accomplished a total of 289, or 78 per cent. Only 85 objectives, or 22 per cent, attempted were not completed, and 26 of these 85 were not finished because of a lack of time at the end of the school year.

The problem of this study is twofold. The first is to discover in what ways are physics teachers and counselors in large Texas public secondary schools encouraging students to take physics, and second, what are their perceptions of reasons for student avoidance of physics. The population consisted of physics teachers and counselors in large (1,310 minimum enrollment) high and low percentage physics enrollment schools. Percentage enrollment in physics is defined as the number of students enrolled in physics compared to total twelfth grade enrollment. Thirty high (above 8.9) and thirty low (below 8.0) percentage enrollment schools comprise the sample population. Data were collected using separate questionnaires that related to (a) school, (b) physics teacher, and (c) counselor variables that could affect physics enrollments. The questionnaires addressed to perceptions of both physics teachers and counselors covered (a) the exchange of physics course information between students, teachers, and counselors, (b) the method of exchange of physics course information, and (c) the extent to which the physics program is sold to the student body. Also elicited were eleven responses from both physics teachers and counselors that pertain to perceived reasons for student avoidance of physics courses. A statistical analysis was made between physics teachers and counselors perceptions pairing high and low percentage enrollment groups by chi square analysis of each item of the questionnaire, using a .05 level for significance.

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British involvement in Ethiopia after 1896 became necessary to stop French activities in the Nile Basin and to block Ethiopian expansion toward the White Nile. After wringing guarantees concerning the Ethiopian sources of the Nile from the Emperor Manilek, Great Britain worked to prevent any potentially dangerous European power from gaining overwhelming predominance at the Ethiopian Court. Thus, in pursing her own interests in Egypt and the Nile Valley, England stood at the same time as a guarantor of Ethiopia's sovereignty [TRUNCATED]

U.M.

Bloomington, Ill., 1940. 196p.

144p.

156p.

, no.137, 1939. 222p.

219p.

57: 976-81, 1940