Browsing by Author "Bekele, Tamirat"

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    A Study of the Equatorial Ionization Anomaly from Champ Satellite Ion Density Data
    (Addis Ababa University, 2008-09) Bekele, Tamirat; Belay, Esayas (PhD)
    The equatorial ionization anomaly and equatorial electrojet are typical plasma dynamic processes of the equatorial ionosphere. Equatorial ionization anomaly is characterized as the occurrence of a trough in the ionization concentration at the equator and crests from about ±150 to ±200 in magnetic latitude in each hemisphere. Equatorial electrojet, on the other hand, is an intense electric current flowing in the E region of the ionosphere during the day time to the east direction. The aim of this thesis is to study the seasonal, longitudinal, latitudinal and early evening characteristics of the equatorial ionization anomaly. In addition, we have drawn a tentative relationship between the equatorial ionization anomaly and equatorial electrojet. To accomplish these purposes, we have analyzed seven years (2000- 2006) of CHAMP Satellite’s ion density and magnetometer (current profiles) data. The results obtained show that the equatorial ionization anomaly varies rapidly with latitude as well as with longitude. It also exhibits a day to day and seasonal variation. The early evening anomaly structures are quite different from the noon times. In addition, both equatorial ionization anomaly and equatorial electrojet depend on the solar activity and a strong relationship exists between the two phenomena
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    A Study on the Status of Public Primary School Physical Plants in Addis Ababa
    (Addis Ababa University, 1999-05) Bekele, Tamirat; Shibeshi, Ayalew (PhD)
    r be purpose of the study was to make a survey on the current status of public primary .cbools in the city of Addis Ababa. Ute needed data was obtained by means of questionnaires distributed to 30 school \U1cipa!s, 28 members of school administrative committees, and 210 teachers working in Upublic primary schools randomly selected from five study "Zones" of the city. it data was analyzed using both descriptive and inferential statistics. Accordingly the !leiI.fch revea led the following results. fit of public school physical plants were found to be inadequate to implement various ~cl programmes because they were not primarily designed for educational purposes, ~~yen those which were designed for educational purposes were built without overall gS,S/S\Ilents and appropriate design. lnaddition, more than half of the public schools did t; ~~e legally acceptable school map and plan. 0 0 Ir1 -t::bcs\udy, school principals and teachers showed much .similar perception with regard 'VlIating the adequacy and comfortability of school plants than members of school to e jJT;.trative committees. a~ 1 -c thool physical plants were not located according to their functional relationships pub "J o \tes comfortable for teaching-learning processes. Hence, the school compounds, and 0 cl&stoOms, staff-rooms and offices were not convenient for teaching-Ieaming tb e seland administrative activities. Almost all public school physical plants were by (oceS P 1 ~the standard set by the MOE. fi:l(be 0 . scl\)ols lack the necessary repair and maintenance, for the reason that the public onsibiliy was left to school administrative committeeS-Almost all of the respondents resP. d Jltither the ed ucatI.O na I 0 ffiI ces nor t he surroun dm' g commuru.t y m. vo Iv ed m. . dlcate Ill . d llIlintenance of public schools. repaIr an Most of these schools did not have educational facilities like libraries, laboratories, space and facilities for subjects that require practical activities. The mam financial sources for public schools were found to be school fees. The participation of school committees, parents, the surrounding community in the affairs of public school physical plants was insignificant. There are no clear-cut policy statements and general guidelines about the organization and administration of public schools. If these problems are to be met forth rightly and directly, then careful planning and study are necessary. If successful solutions with successful answers are to be arrived at, cooperative action is desired between professional educational staff, the board of education, other community agencies and all citizens of the community.