An exergy based engineering and economic analysis of sustainable building

To achieve the goal of sustainable development, the building energy system was evaluated from both the first and second law of thermodynamics point of view. The relationship between exergy destruction and sustainable development were discussed at first, followed by the description of the resource abundance model, the life cycle analysis model and the economic investment effectiveness model. By combining the forgoing models, a new sustainable index was proposed. Several green building case studies in U.S. and China were presented. The influences of building function, geographic location, climate pattern, the regional energy structure, and the technology improvement potential of renewable energy in the future were discussed. The building’s envelope, HVAC system, on-site renewable energy system life cycle analysis from energy, exergy, environmental and economic perspective were compared. It was found that climate pattern had a dramatic influence on the life cycle investment effectiveness of the building envelope. The building HVAC system energy performance was much better than its exergy performance. To further increase the exergy efficiency, renewable energy rather than fossil fuel should be used as the primary energy. A building life cycle cost and exergy consumption regression model was set up. The optimal building insulation level could be affected by either cost minimization or exergy consumption minimization approach. The exergy approach would cause better insulation than cost approach. The influence of energy price on the system selection strategy was discussed. Two photovoltaics (PV) systems—stand alone and grid tied system were compared by the life cycle assessment method. The superiority of the latter one was quite obvious. The analysis also showed that during its life span PV technology was less attractive economically because the electricity price in U.S. and China did not fully reflect the environmental burden associated with it. However if future energy price surges and PV system cost reductions were considered, the technology could be very promising for sustainable buildings in the future.

An Exergy Based Engineering and Economic Analysis of Sustainable Building

To achieve the goal of sustainable development, the building energy system was evaluated from both the first and second law of thermodynamics point of view. The relationship between exergy destruction and sustainable development were discussed at first, followed by the description of the resource abundance model, the life cycle analysis model and the economic investment effectiveness model. By combining the forgoing models, a new sustainable index was proposed. Several green building case studies in U.S. and China were presented. The influences of building function, geographic location, climate pattern, the regional energy structure, and the technology improvement potential of renewable energy in the future were discussed. The building’s envelope, HVAC system, on-site renewable energy system life cycle analysis from energy, exergy, environmental and economic perspective were compared. It was found that climate pattern had a dramatic influence on the life cycle investment effectiveness of the building envelope. The building HVAC system energy performance was much better than its exergy performance. To further increase the exergy efficiency, renewable energy rather than fossil fuel should be used as the primary energy. A building life cycle cost and exergy consumption regression model was set up. The optimal building insulation level could be affected by either cost minimization or exergy consumption minimization approach. The exergy approach would cause better insulation than cost approach. The influence of energy price on the system selection strategy was discussed. Two photovoltaics (PV) systems – stand alone and grid tied system were compared by the life cycle assessment method. The superiority of the latter one was quite obvious. The analysis also showed that during its life span PV technology was less attractive economically because the electricity price in U.S. and China did not fully reflect the environmental burden associated with it. However if future energy price surges and PV system cost reductions were considered, the technology could be very promising for sustainable buildings in the future.

Technology professional development for principals: Impact on the integration of technology in elementary schools

The use of technology in schools is no longer the topic of educational debates, but how to ensure that technology is used effectively continues to be the focal point of discussions. The role of the principal in facilitating the successful integration of technology in the school is well established. To that end, the Florida Department of Education implemented the FloridaLeaders.net: a three-year professional development project in technology for school administrators. The purpose of this study was to investigate the effectiveness of this professional development project on integrating technology in elementary schools. ^ The study compared a group of schools whose principals have participated in the FloridaLeaders.net (FLN) program with schools whose principals have not participated in the program. The National Technology Standards for School Administrators and the National Technology Standards for Teachers were used as the framework to assess technology integration. ^ The sample consisted of three groups of educators: principals (n = 47), media specialists (n = 110), and teachers (n = 167). Three areas of technology utilization were investigated: (a) the use of technology in management and operations, (b) the use of technology in teaching and learning, and (c) the use of technology for assessment and evaluation. Analyses of variances were used to examine the differences in the perceptions and use of technology in each of the three areas, among the three groups of educators. ^ The findings indicated that the difference between FLN and non-FLN schools was not statistically significant in most of the technology indicators. The difference was however significant in two cases: (a) The use of technology for assessment and evaluation, and (b) The level of technology infrastructure in FLN schools. Additionally, all FLN and non-FLN groups reported the need for technology training for teachers to provide them with the necessary "know-how" to effectively integrate technology into the classrooms. ^ These findings would indicate that FloridaLeaders.net was not effective in integrating technology in schools over and above other current efforts. It is therefore concluded that the FLN project had some favorable impact but had not met all of its stated objectives. ^

Computational evaluation of wind loads on low- and highrise buildings

Buildings and other infrastructures located in the coastal regions of the US have a higher level of wind vulnerability. Reducing the increasing property losses and causalities associated with severe windstorms has been the central research focus of the wind engineering community. The present wind engineering toolbox consists of building codes and standards, laboratory experiments, and field measurements. The American Society of Civil Engineers (ASCE) 7 standard provides wind loads only for buildings with common shapes. For complex cases it refers to physical modeling. Although this option can be economically viable for large projects, it is not cost-effective for low-rise residential houses. To circumvent these limitations, a numerical approach based on the techniques of Computational Fluid Dynamics (CFD) has been developed. The recent advance in computing technology and significant developments in turbulence modeling is making numerical evaluation of wind effects a more affordable approach. The present study targeted those cases that are not addressed by the standards. These include wind loads on complex roofs for low-rise buildings, aerodynamics of tall buildings, and effects of complex surrounding buildings. Among all the turbulence models investigated, the large eddy simulation (LES) model performed the best in predicting wind loads. The application of a spatially evolving time-dependent wind velocity field with the relevant turbulence structures at the inlet boundaries was found to be essential. All the results were compared and validated with experimental data. The study also revealed CFD's unique flow visualization and aerodynamic data generation capabilities along with a better understanding of the complex three-dimensional aerodynamics of wind-structure interactions. With the proper modeling that realistically represents the actual turbulent atmospheric boundary layer flow, CFD can offer an economical alternative to the existing wind engineering tools. CFD's easy accessibility is expected to transform the practice of structural design for wind, resulting in more wind-resilient and sustainable systems by encouraging optimal aerodynamic and sustainable structural/building design. Thus, this method will help ensure public safety and reduce economic losses due to wind perils.

Computational Evaluation of Wind Loads on Low- and High- Rise Buildings

Buildings and other infrastructures located in the coastal regions of the US have a higher level of wind vulnerability. Reducing the increasing property losses and causalities associated with severe windstorms has been the central research focus of the wind engineering community. The present wind engineering toolbox consists of building codes and standards, laboratory experiments, and field measurements. The American Society of Civil Engineers (ASCE) 7 standard provides wind loads only for buildings with common shapes. For complex cases it refers to physical modeling. Although this option can be economically viable for large projects, it is not cost-effective for low-rise residential houses. To circumvent these limitations, a numerical approach based on the techniques of Computational Fluid Dynamics (CFD) has been developed. The recent advance in computing technology and significant developments in turbulence modeling is making numerical evaluation of wind effects a more affordable approach. The present study targeted those cases that are not addressed by the standards. These include wind loads on complex roofs for low-rise buildings, aerodynamics of tall buildings, and effects of complex surrounding buildings. Among all the turbulence models investigated, the large eddy simulation (LES) model performed the best in predicting wind loads. The application of a spatially evolving time-dependent wind velocity field with the relevant turbulence structures at the inlet boundaries was found to be essential. All the results were compared and validated with experimental data. The study also revealed CFD’s unique flow visualization and aerodynamic data generation capabilities along with a better understanding of the complex three-dimensional aerodynamics of wind-structure interactions. With the proper modeling that realistically represents the actual turbulent atmospheric boundary layer flow, CFD can offer an economical alternative to the existing wind engineering tools. CFD’s easy accessibility is expected to transform the practice of structural design for wind, resulting in more wind-resilient and sustainable systems by encouraging optimal aerodynamic and sustainable structural/building design. Thus, this method will help ensure public safety and reduce economic losses due to wind perils.

Sustainability Evaluation of Green Building Certification Systems

The attention on green building is driven by the desire to reduce a building’s running cost over its entire life cycle. However, with the use of sustainable technologies and more environmentally friendly products in the building sector, the construction industry contributes significantly to sustainable actions of our society. Different certification systems have entered the market with the aim to measure a building’s sustainability. However, each system uses its own set of criteria for the purpose of rating. The primary goal of this study is to identify a comprehensive set of criteria for the measurement of building sustainability, and therefore to facilitate the comparison of existing rating methods. The collection and analysis of the criteria, identified through a comprehensive literature review, has led to the establishment of two additional categories besides the 3 pillars of sustainability. The comparative analyses presented in this thesis reveal strengths and weaknesses of the chosen green building certification systems - LEED, BREEAM, and DGNB.

Humanizing the facade of the public commercial building in a contemporary American culture

The projects studied for this thesis show that the more the façades match the values, tastes, and needs of its target individuals, the more frequently the place will be visited. They endow it with a sense of place and uniqueness and create an emotional bond with the individuals. The intent of this research was to derive a framework of principles to be used in the design of façades, and to establish a relationship between the facade, human scale, urban context, and building. The methodology for developing this framework is based on the analysis of building façades from the Renaissance to current examples of New York Times Square. The principles were generated from strategies of the case studies analyzed. Principles of monumentality, symbolism, and iconography were used to perceive façades as essential forms of architecture. The scale of facades emphasizes human dimensions. In turn, the façade is a device of communication to inform individuals, and its impact on retelling culture for a city.

A comparison of a distance education and locally based course in an urban university setting

The purpose of this research was to compare the academic performance and attitudes of students at the instructor-based site of a televised course and the distant site. An earlier pilot program indicated the need for certain technical and structural interventions at the distant site such as multiple "press-to-touch" microphones, a site-administrator and participative seating arrangements. At the beginning of the class, demographic data were collected from the students at both sites through a questionnaire and supplemented with information from students' records. Factors such as age, gender, ethnicity, marital status, number of children, current class status, major, work status and CLAST scores (achievement tests) were examined. There were no significant differences between the students at the sites except ethnicity and reading CLAST scores. The instructor-based site had a higher percentage of Hispanic students and the distant site had a larger percentage of Caucasian and Black Americans. The distant site scored significantly better on the reading section of the CLAST achievement test. An evaluation instrument was distributed to both sites, at the midpoint of the semester, measuring their attitude toward the organizational, technical, and pedagogical factors of the course. A second evaluation instrument, measuring similar factors, but more in-depth, was distributed to both sites near the end of the term. Nine students at the distant site were interviewed along with the site administrator to collect additional information.^ Course completion rates, dropout rates, pass rates and final grades of students at both sites were compared. There were no significant differences in academic performance between the students at both sites, however, there were significant differences in their attitudes. Those at the instructor-based site gave better ratings to most of items in the evaluation instruments. Problems at the distant site included audio and visual clarity, lack of available assistance, too much nonrelated talking, not enough opportunities to ask questions or to interact with the instructor during class. ^

The effect of mentoring electronic mail on student achievement and attitudes in a graduate course in educational research

This exploratory study of a classroom with mentoring and neutral e-mail was conducted in a public commuter state university in South Florida between January 1996 and April 1996. Sixteen males and 83 females from four graduate level educational research classes participated in the study.^ Two main hypotheses were tested. Hypothesis One was that those students receiving mentoring e-mail messages would score significantly higher on an instrument measuring attitude toward educational research (ATERS) than those not receiving mentoring e-mail messages. Hypothesis Two was that those students receiving mentoring e-mail would score significantly higher on objective exams covering the educational research material than those not receiving mentoring e-mail.^ Results of factorial analyses of variance showed no significant differences between the treatment groups in achievement or in attitudes toward educational research. Introverts had lower attitudes and lower final exam grades in both groups, although introverts in the mentored group scored higher than those introverts in the neutral group.^ A t test of the means of total response to e-mail from the researcher showed a significant difference between the mentored and neutral e-mail groups. Introverts responded more often than extraverts in both groups.^ Teacher effect was significant in determining class response to e-mail messages. Responses were most frequent in the researcher's classes.^ Qualitative analyses of the e-mail and course evaluation survey and of the content of e-mail messages received by the researcher were then grouped into basic themes and discussed.^ A qualitative analysis of an e-mail and course evaluation survey revealed that students from both the neutral and mentoring e-mail groups appreciated teacher feedback. A qualitative analysis of the mentoring and neutral e-mail replies divided the responses into those pertaining to the class, such as test and research paper questions, and more personal items, such as problems in the class and personal happenings.^ At this point in time, e-mail is not a standard way of communicating in classes in the college of education at this university. As this technology tool of communication becomes more popular, it is anticipated that replications of this study will be warranted. ^

The effects of bilingual and monolingual reading videos on story recall with students who are deaf and hard of hearing

The purpose of this study is to investigate the effects of bilingual and monolingual videos on the reading comprehension of students with significant hearing impairments and/or deafness. Children with and without hearing losses need reading programs in which comprehension of meaning is the primary goal. This can occur only when print is represented in meaningful context, allowing children to create meaning from their own experience, background, and knowledge of language.^ Investigated in this study was whether students with significant hearing losses comprehended more information in a bilingual or monolingual instructional video format. There were three instructional videos produced: (a) the bilingual video which incorporated American Sign Language (ASL) with standard English captions, (b) a monolingual English video with standard English captions only, and (c) a monolingual ASL-only video. It was hypothesized that the effects of English captioning with ASL might serve as a bridge during instruction, increasing reading comprehension and written English for students. It was further hypothesized that this would allow students to integrate their own ASL knowledge to the printed text to construct meaning.^ Four separate analyses were conducted to see if the hypothesis was supported by the findings. However, all results indicated that there were no significant differences in students' written measures of reading comprehension recall across any of the three presentations of information (two monolingual and one bilingual condition). There were seven variables (word identification, word recall, sentence recall, story recall, written passage theme, written passage word count, and number of mature words) used to evaluate reading comprehension recall. No variable, either individually or grouped, demonstrated a significant difference between monolingual or bilingual instruction. ^

A comparison of the impact of trained media specialists and untrained media personnel in junior colleges in the Republic of China

From educational, communications, psychological, and technical points of view, the renovation of pedagogy in media education is based upon the promotion of "educational technology." The promotion of educational technology relies upon the appropriate availability and knowledge of different educational media made available by the trained media personnel.^ In the past three decades most of the junior colleges in Taiwan set up educational media centers to help students learn through the use of media which enables them to obtain optimum benefits in a short time. What are the roles the media personnel play in the media center? What responsibilities have they to bear in the center? What differences are there when a trained and untrained media personnel are presented in junior colleges media center in Taiwan? What do the trained and untrained media personnel feel toward the importance of each media service in the area of media center's administration, media production, specialized media duties, and the training of staff in media use? These are the questions addressed in this study.^ Through the study of the related literature and a survey conducted in the junior colleges in Taiwan, recommendations are offered to provide improvement of the services and training of media specialists in Taiwan that are appropriate for a changing work and environment. These recommendations are for media specialists to be formally trained to effectively serve the changing needs of school library media so as to make optimal use of media in the junior colleges. ^

A distance education case study: A comparison of instructional delivery methods practiced by higher education faculty and emerging standards

The purpose of this research was to compare the delivery methods as practiced by higher education faculty teaching distance courses with recommended or emerging standard instructional delivery methods for distance education. Previous research shows that traditional-type instructional strategies have been used in distance education and that there has been no training to distance teach. Secondary data, however, appear to suggest emerging practices which could be pooled toward the development of standards. This is a qualitative study based on the constant comparative analysis approach of grounded theory.^ Participants (N = 5) of this study were full-time faculty teaching distance education courses. The observation method used was unobtrusive content analysis of videotaped instruction. Triangulation of data was accomplished through one-on-one in-depth interviews and from literature review. Due to the addition of non-media content being analyzed, a special time-sampling technique was designed by the researcher--influenced by content analyst theories of media-related data--to sample portions of the videotape instruction that were observed and counted. A standardized interview guide was used to collect data from in-depth interviews. Coding was done based on categories drawn from review of literature, and from Cranton and Weston's (1989) typology of instructional strategies. The data were observed, counted, tabulated, analyzed, and interpreted solely by the researcher. It should be noted however, that systematic and rigorous data collection and analysis led to credible data.^ The findings of this study supported the proposition that there are no standard instructional practices for distance teaching. Further, the findings revealed that of the emerging practices suggested by proponents and by faculty who teach distance education courses, few were practiced even minimally. A noted example was the use of lecture and questioning. Questioning, as a teaching tool was used a great deal, with students at the originating site but not with distance students. Lectures were given, but were mostly conducted in traditional fashion--long in duration and with no interactive component.^ It can be concluded from the findings that while there are no standard practices for instructional delivery for distance education, there appears to be sufficient information from secondary and empirical data to initiate some standard instructional practices. Therefore, grounded in this research data is the theory that the way to arrive at some instructional delivery standards for televised distance education is a pooling of the tacitly agreed-upon emerging practices by proponents and practicing instructors. Implicit in this theory is a need for experimental research so that these emerging practices can be tested, tried, and proven, ultimately resulting in formal standards for instructional delivery in television education. ^

The effectiveness of an intelligent tutoring system on the attitude and achievement of developmental mathematics students in a community college

This study examined the effectiveness of intelligent tutoring system instruction, grounded in John Anderson's ACT theory of cognition, on the achievement and attitude of developmental mathematics students in the community college setting. The quasi-experimental research used a pretest-posttest control group design. The dependent variables were problem solving achievement, overall achievement, and attitude towards mathematics. The independent variable was instructional method.^ Four intact classes and two instructors participated in the study for one semester. Two classes (n = 35) served as experimental groups; they received six lessons with real-world problems using intelligent tutoring system instruction. The other two classes (n = 24) served as control groups; they received six lessons with real-world problems using traditional instruction including graphing calculator support. It was hypothesized that students taught problem solving using the intelligent tutoring system would achieve more on the dependent variables than students taught without the intelligent tutoring system.^ Posttest mean scores for one teacher produced a significant difference in overall achievement for the experimental group. The same teacher had higher means, not significantly, for the experimental group in problem solving achievement. The study did not indicate a significant difference in attitude mean scores.^ It was concluded that using an intelligent tutoring system in problem solving instruction may impact student's overall mathematics achievement and problem solving achievement. Other factors must be considered, such as the teacher's classroom experience, the teacher's experience with the intelligent tutoring system, trained technical support, and trained student support; as well as student learning styles, motivation, and overall mathematics ability. ^

An investigation into the comparable effectiveness of two tests of writing administered to college-level English as a Second Language students: The Computerized Placement Test and holistically scored essay exams

This dissertation describes the findings and implications of a correlational analysis. Scores earned on the Computerized Placement Test (CPT), sentence skills, were compared to essay scores of advanced English as a Second Language (ESL) students. As the CPT is designed for native speakers of English, it was hypothesized that it could be an invalid or unreliable instrument for non-native speakers. Florida community college students are mandated to take the CPT to determine preparedness, as are students at many other U.S. and Canadian colleges. If incoming students score low on the CPT, they may be required to take up to three semesters of remedial coursework. It is essential that scores earned by non-native speakers of English accurately reflect their ability level. They constitute a large and growing body of non-traditional students enrolled at community colleges.^ The study was conducted at Miami-Dade Community College, Wolfson Campus, fall 1997. Participants included 106 advanced ESL students who took both the CPT sentence skills test and wrote final essay exams. The essay exams were holistically scored by trained readers. Also, the participants took the Placement Articulation Software Service (PASS) exam, an alternative form of the CPT. Scores on the CPT and essays were compared by means of a Pearson product-moment correlation to validate the CPT. Scores on the CPT and the PASS exam were compared in the same manner to verify reliability. A percentage of appropriate placements was determined by comparing essay scores to CPT cutoff score ranges. Finally, the instruments were evaluated by means of independent-samples t-tests for performance differences between gender, age, and first language groups.^ The results indicate that the CPT sentence skills test is a valid and reliable placement instrument for advanced- level ESL students who intend to pursue community college degrees. The correlations demonstrated a substantial relationship between CPT and essay scores and a marked relationship between CPT and PASS scores. Appropriate placements were made in 86% of the cases. Furthermore, the CPT was found to discriminate equally among the gender, age, and first language groups included in this study. ^