Considerations for performance evaluation of solar heating and cooling systems

One of the many factors which must be considered in performance evaluation of solar energy systems is the relative merit of a given solar energy system when compared to a standard conventional system. Although initial and operational costs will be dominant factors in the comparison of the two types of systems and will be given prime consideration in system selection, sufficient data are not yet available for a definitive treatment of these variables. It is possible, however, to formulate relationships between the nonsolar energy requirements of the solar energy systems and the energy requirements of a conventional system in terms of the primary performance parameters of the systems. Derivations of such relationships, some parametric data for selected ranges of the performance parameters, and data with respect to limiting conditions are presented

Why We Can't Wait -- A Case for Philanthropic Action: Opportunities for Improving Life Outcomes for African American Males

This report examines programs and initiatives that impact the life outcomes of African-American males, gathers reflections from the field, and assesses needs and opportunities according to scholars, policy makers, advocates, and organizational leaders. The report documents its findings and recommendations in three categories: academia/research, practitioners/civil society, and public policy/advocacy

Nucleate pool boiling of saturated Freon 113 in a reduced gravity environment

Nucleate pool boiling of saturated Freon 113 in reduced gravity environmen

Design and operation of a solar heating and cooling system for a residential size building

The first year of operation of solar house is discussed. Selected design information, together with a brief system description is included. The house was equipped with an integrated solar heating and cooling system which uses fully automated state-of-the art. Evaluation of the data indicate that the solar house heating and cooling system is capable of supplying nearly 100 percent of the thermal energy required for heating and approximately 50 percent of the thermal energy required to operate the absorption cycle air conditioner

Experimental transient three-dimensional heat transfer analysis

Time function, and transient three-dimensional heat transfer analysi

MSFC Skylab thermal and environmental control system mission evaluation

An evaluation of the performance of the Skylab thermal and environmental control system is presented. Actual performance is compared to design and functional requirements and anomalies and discrepancies and their resolution are discussed. The thermal and environmental control systems performed their intended role. Based on the experience gained in design, development and flight, recommendations are provided which may be beneficial to future system designs

MATERIALS AND STRUCTURES PROGNOSIS FOR GAS TURBINE ENGINES

ABSTRACT Gas turbine engine diagnostic systems often utilize data trending and anomaly detection to provide a measure of system health. These systems provide significant benefits for trending shifts in engine performance and diagnosing system degradation that requires some maintenance action. However, this approach may be limited in the ability to uniquely identify damage for select components and failure modes. Advanced prognostic systems are being developed to work symbiotically with state of the art diagnostic techniques in use today; these advanced systems use advanced material and component damage evolution modelling linked with system-level structural analyses to intelligently guide the health management system to search for specific signatures that would be expected from key changes in component and system health Material damage models, advanced component models, and novel system-level structural analyses are being used to generate newly defined "structural transfer functions" (STFs) that provide a link between sensed parameters and the remaining capability of specific components, and the system. The characteristic damage signatures vary by component type and failure mode, and hence the specific STF approach varies among component types. An initial STF approach was developed and demonstrated for a specific component and damage typ

Freire's Pedagogy of Love and a Ph.D. Student's Experience

This article offers an interpretation of Freire’s concept of pedagogical love in a word to world— theory to practice—approach. We offer a definition of the term love; then present coauthor’s Steven’s narrative as an illustration of a real life experience of Freirean pedagogical love. The goal is to begin a conversation about the transformative value of an instructional model rooted in Freire’s pedagogy of emancipatory love; and to seek ways in which this model is applicable to writing centers and other educational settings—not just in colleges, but also K-12 environments.University Writing Cente