Dissertations and Theses (1964-2011)

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In 2018 BU Libraries began a retrospective digitization project for BU theses and dissertations dating from 1964-2011. If you cannot locate your thesis or dissertation in OpenBU, it may not have been digitized yet. If you have any questions about this collection, please contact us at open-help@bu.edu.

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Russian-American relations, 1820-1830: the diplomacy of Henry Middleton, American minister at St. Petersburg
(Boston University, 1970) Bergquist, Harold Edward
An assessment of the learning needs and aspirations of out-of-school rural youths on the family island of exuma in the Bahamas (Caribbean, rural development)
(Boston University, 1987) Ramirez, Christine Carolyn
This study was designed to determine and analyse the learning needs and aspirations of rural youth on the Family Island of Exuma in The Bahamas. Data collected through structured interviews were examined from the perspectives of rural youths between the ages of 17 through 21, their parents, educators and community leaders. The following findings emerged as the most significant in the study: (1) There is, at present, a mismatch between the present national development plans and/or policies which contributes to imbalances in both the educational and economic sectors of Exuma. There are three areas in which the case of this mismatch is most salient: (a) rural-urban disparities in planning for development of the Exumian educational and economic sectors, (b) a mismatch between the school curriculum, job requirements and general needs of the economic sector, and (c) an over-emphasis on academic learning that is viewed as the only way to achieve one's educational and occupational aspirations. (2) There is generally a lack of parental involvement in the schools. This absence is perceived by the community as evidence of a poor parental attitude towards the educational development of their children. (3) Outward migration by youth is on the rise because of the lack of educational and economic opportunities on Exuma. (4) There is a reported increase in social problems (crime and the unemployment rate) on the island. These problems are said to be associated with drug trafficking. Based upon the research findings and data analyses, a set of recommendations was formulated to aid policy makers, educational planners and others concerned with planning for rural youth's needs. These recommendations follow from the basic finding that Exumians are too highly dependent on outside sources for their educational and economic needs.
Binaural detection performance using reproductible stimuli
(Boston University, 1995) Isabelle, Scott K.
A listener's sensitivity to the presence of a sinusoidal target, masked by a sample of random noise, is known to depend on the specific noise sample for both monaural and binaural detection [Gilkey, Robinson, and Hanna, J. Acoust. Soc. Am. 78:1207-1219, 1985]. This work explores to what extent existing quantitative models for binaural detection can predict the sample-by-sample variation observed in listeners' responses. Responses of five subjects for the binaural detection of a 500-Hz, 300-msec, interaurally out-of-phase tone masked by statistically independent samples of narrowband, interaurally-identical noise are reported. A set of 30 noise samples were taken from a noise process with a power spectrum that is 115-Hz wide, centered at 500 Hz. The rms noise pressure is 75 dB SPL. For each subject, the responses show good self-consistency and a strong dependence on individual noise samples (intrasubject correlation coefficients higher than 0.72, typically 0.85). However, there are significant differences between subjects in the pattern of responses across the set of masker samples (intersubject correlation coefficients no higher than 0.7). Subjects' performance values for individual noise samples are compared to the predictions of psychophysical models for binaural detection. Some classes of previously suggested models have predictions that are not consistent with observed performance. Specifically, sample-level predictions of models for which the decision variable is dominated by the energy in the particular noise sample have no significant correlation with the patterns of responses across noise samples for any subject. In contrast, models that are based on variability of the ITD and/ or IID have predictions that are statistically significantly correlated with most subjects' responses (but no correlation coefficients larger than 0. 7). Black-box models in this class include those with decisions based on the sum of the squares of the ITDs and IIDs, or on the peak-deviations of the ITDs. Results for a physiological model of the dependence of firing patterns of the principal cells in the medial superior olive on ITDs suggest a mechanism that is analogous to black-box models with decision variables based on the variability of the ITD.
Optoelectronic properties of aluminum gallium nitride / gallium nitride superlattices
(Boston University, 2003) Waldron, Erik Laker
In this thesis, three primary findings are presented concernmg optolelectronic properties of AlGaN superlattices. First, we obtain the lowest lateral p-type resistivity and highest lateral p-type mobility to date in the AlGaN material system. Second, we obtain the first experimental results of multi-subband photoluminescence in p-type AlGaN superlattices. Last, we report the first direct measurement of perpendicular electrical transport ( electrical transport perpendicular to the superlattice planes) in AlGaN superlattices. Our research into resistivity and mobility of AlGaN superlattices stems from the fact that p-type AlGaN is highly resistive. To overcome the problem of highly resistive p-type AlGaN, we propose and demonstrate modulation doping in p-type AlGa superlattices. Our measurements yield a low-temperature lateral resistivity and mobility of 0.068 S1 • cm and 36 cm 2 /(V • s), respectively. This is the lowest resistivity and highest mobility recorded to date in p-type AlGaN and results from reduced ionized impurity scattering inherent in modulation doping. The optical properties of AlGaN superlattices are of great interest because they are often used in light-emitting diodes and laser diodes. Specifically, the absorption edge in AlGaN superlattices is typically thought of as being severely red-shifted due to internal electric fields present in AlGaN-based materials. We obtain experimental photoluminescence results on large-period superlattices that indicate that the redshifting of the absorption edge is much less than previously thought due to the combined effects of band-filling and oscillator strength on energy. We develop a computer model based on the self-consistent solution of the Poisson and Schrodinger system of equations. Our model predicts a drastic decrease in spontaneous recombination lifetime with increased transition energy, which is consistent with our experimental data. The perpendicular resistivity of AlGaN superlattices is also of critical importance to the development of AlGaN-based devices. We therefore measured the perpendicular resistivity of an n-type AlGaN superlattice and compared it to bulk n-type GaN. The superlattice has a perpendicular resistivity of 1.2 D • cm while bulk n-type GaN is 0.18 D • cm. We develop a theoretical model based on sequential tunneling and enhanced free carrier concentration to explain our experimental findings. Our model shows that perpendicular resistivity is dominated by two factors; carrier concentration and tunneling probability.
An ESP-mediumship paradigm as a definition of mediumship
(Boston University, 1980) Bedar, Bradford Bruce
Parapsychologists have debated for nearly a century the question of whether to attribute the source of mediumistic phenomena to the postulated vast extrasensory perception (ESP) abilities of the living (L. E. Rhine, 1966) or to the ostensible deceased personalities with whom mediums claim to be able to "communicate". Gauld (1977) has suggested that this debate between the ESP hypothesis and the survivalist hypothesis has reached a stalemate. The purpose of this thesis was to develop a paradigm that qualitatively defines the relationship between ESP and mental mediumship in order to demonstrate that mediumship represents a definable and unitary class of phenomena. The two major assumptions of mediumship were investigated in order to provide a context and structure upon which an ESP-mediumship paradigm could be constructed. The two assumptions are (1) the question of survival, and (2) the question of communication with ostensible deceased personalities. The survival question examined the following areas: (1) apparitions, (2) out-of-body experiences (OBE's), and (3) deathbed experiences. The communication question investigated (1) multiple personalities vs. trance personalities, (2) quantitative analysis of trance communicators, (3) inconsistencies of trance communications, and (4) ESP vs. mediumship as a means of communication. An ESP-mediumship paradigm was then developed based on clearly articulated assumptions concerning the properties of ESP and mediumship. It was postulated that certain criteria could be extracted from exemplary cases of mediumship, and that these criteria could represent the critical points of discrimination between the known limits of ESP and mediumship. The criteria were then used to define the two parameters of the ESP-mediumship paradigm. It was further postulated that the criteria along the two parameters would be able to generate the relationships between ESP and mediumship. Five exemplary cases of mediumship were then reviewed and discussed according to these criteria. Results of the investigation of the two major assumptions of mediumship indicated that the ESP hypothesis could not explain apparitional cases of group experience or OBE's more parsimoniously than the survivalist hypothesis. Also, take-away apparitions seen by the dying indicated a significant core of characteristics, such as the ostensible purpose of the apparition as well as the dying person's peaceful reaction to the apparition (Osis and Haraldsson, 1977). The results of the investigation of the five exemplarycases of mediumship indicated that cases of mediumship could be scrutinized and evaluated by the ESP-mediumship paradigm. It was shown that according to the criteria, particular cases of mediumship such as drop-in cases and cross communications, extended beyond the known limits of ESP. It was also indicated that the survivalist hypothesis provided a more parsimonious explanation than the ESP hypothesis for cases in which collated knowledge from more than one source had to be postulated; and in cases in which there v/as evidence of knowledge beyond the capacity of the medium, but characteristic of the ostensible deceased entity. The conclusion of the thesis was that the ESP-mediumship paradigm was able to generate and define the relationships between ESP and mediumship. Also, the paradigm indicated that according to its criteria mediumship can be defined as a unitary class of phenomena.
Factors of achievement and femininity as predictors of career commitment in college senior women
(Boston University, 1974) Hanley, Mary Ann
According to Erik Erikson, emphasis on identity formation for young women centers on femininity concerns. Robert White also emphasized competence, especially in work. These two goals may be conflicting for young women as they finish college and plan for career or marriage or both. This study is an attempt to relate some achievement and femininity factors to career commitment and to one another. Ninety-eight college senior women from a highly selective women's college were measured on seven predictor variables and the criterion variable, career commitment. The following major hypotheses were supported: there is a significant, positive relationship between career commitment and sense of competence in work situations, achievement need, and perceived approval of significant males for career plans; there is a significant, negative relationship between career commitment and identification with a feminine stereotype and fear of success. An hypothesized positive relationship between career commitment and non-traditional career choice was not supported. Also not supported was a prediction that the relationship between career commitment and perceived success informing romantic male/female relationships would vary as a function of life style choice. Secondary hypotheses that were supported were predictions that identification with a feminine stereotype is significantly and negatively related to non-traditional career choice, achievement need and approval of significant males; achievement need is significantly and positively related to non-traditional career choice and sense of competence. In addition to the simple correlational analyses, a multiple regression equation was computed in order to rank the variables in predicting career commitment. The first three variables to enter were sense of competence, fear of success and feminine stereotype. Achievement need also had a relatively strong relationship with career commitment, but did not enter early because it shared variance with more strongly related variables. A posteriori analyses were done after major hypotheses had been tested. Some questionnaire data, in combination with the original variables, were included in a supplementary multiple regression equation. Sense of competence was still the best predictor of career commitment. However, whether or not mother worked while subject was growing up entered as the second step. Other variables which, in combination with earlier entries, significantly predicted career commitment were summer work experience, mother's attitude toward women with young children having careers, socio-economic status and approval by others (both sexes). Fear of success and feminine stereotype were still important, but less so than in the original multiple regression. In another supplementary analysis, Chi squares showed that there was a significant relationship between career commitment and mother's work patterns, time when subjects plan to marry, part-time work experience and father's approval of women--even those with small children--having careers. A supplementary discriminant analysis, using original variables but changing the criterion, indicated that achievement need, approval of significant males and feminine stereotyle were the best combination of predictors of traditional or non-traditional career choice. This study supports the findings that achievement need and approval of significant males were positively related to career commitmen.t; it supports the theories that feminine stereotype and fear of success should be negatively, and sense of competence, positively, related to career commitment. Contrary to other's findings, non-traditional career choice was not found to be related to career commitment. However, it was related to achievement need. A limitation of this study is that, although many of the correlations were significant, all of them were relatively low. Also, the study was not cross-validated, and the population to which one might generalize is relatively restricted. Further study is suggested for sense of competence, perceived success in forming romantic male/female relationships, mother's work patterns and mother's and father's attitudes about women working.
Two topics on the optimization of manufacturing systems
(Boston University, 1991) Rastogi, Sharad
TOPIC 1 : A Distributed Approach for the Production Flow Control of Interconnected Flezible Manufacturing Systems A dynamic production control policy was developed for interconnected flexible manufacturing systems with stochastic capacity. The objective is to track a desired production rate target in a Just-In-Time manner by minimizing the average production surplus and backlog. The production rate target or demand was assumed to be piecewise constant with respect to time. A 'Manufacturing Flow Control' model was used to allocate dynamically available capacity to the production of various part types. The approach used was distributed, as the production rate at each work cell was scheduled on the basis of local information containing the current inventory level of the adjacent buffers and the present state of the work cell (number of up/down machines). TOPIC 2: Single Run Optimization in Discrete Event Simulations of Manufacturing Systems A new technique was devised to optimize the controllable parameters ( eg. buffer size, batch size, routing proportions, production rate etc.) of stochastic manufacturing systems in a single simulation run. Pertubation Analysis methods were used to estimate the derivatives in a single simulation run of the system model. In addition, a Sequential Hypothesis Testing approach was used to update the parameters on line, as the simulation was running. This algorithm is not only computationally inexpensive but also has the inherent property of escaping from poor local optima.
The six sonatinas for piano of Ferruccio Busoni
(Boston University, 1987) Mockovak, Holly E.
Pianist Ferruccio Busoni (1866–1924), famous for his virtuosity, compelling interpretations and mastery of the art of transcription, also composed prolifically in most every genre. From among his piano compositions, the six sonatinas stand as pieces technically less challenging than the others, though they are equals with regard to their interpretive difficulties. Written between 1910 and 1920, they are products of Busoni's maturity, a maturity inseparable from the reflection of his comprehension of several centuries of musical styles including the developments of the early part of the twentieth century. The very different styles of the sonatinas themselves provide a fair sampling of Busoni's great diversity. The sonatinas are also as formally different from one another as their styles, growing progressively further away from the traditional sonata idea and following, instead, unique abstract programs and formal agendas. Busoni's aesthetics are reviewed and the sonatinas are discussed in context of his entire output. Each sonatina is analyzed, and performance considerations are discussed in light of the analyses.
Learning and recognizing patterns of visual motion, color and form
(Boston University, 1998) Cunningham, Robert Kevin
Animal vision systems make use of information about an object's motion, color, and form to detect and identify predators, prey and mates. Neurobiological evidence from the macaque monkey indicates that visual processing is separated into two streams: the magnocellular primarily for motion, and the parvocellular primarily for color and form. Two computational systems are developed using key functional properties of the two postulated physiological streams. Each produces invariant representations that act as input to separate copies of a new learning and recognition architecture, Gaussian ARTMAP with covariance terms (GAC). Finally, perceptual experiments are conducted to explore the ability of the human form/color system to detect and recognize targets in photo-realistic imagery. GAC, the component common to both computational systems, retains the on-line learning capabilities of previous ARTMAP architectures, but uses categories that have a location and orientation in the dimensions of the feature space. This architecture is shown to have lower error rates than Fuzzy ARTMAP and Gaussian ARTMAP for all data sets examined, and is used to cluster motion and spectral parameters. For the motion system, local velocity measures of image features are obtained by the method of Convected Activation Profiles. This method is extended and shown to accurately estimate the velocity normal to rotating and translating lines, or of line ends, points, and curves. These local measures are grouped into neighborhoods, and the collection of motions within a neighborhood is described using orientation-invariant deformation parameters. Multiple parameters obtained by examining maneuvering objects are clustered, and motions that are characteristic of specific objects are identified. For the form and color system, multi-spectral measurements are made invariant to some fluctuations of local luminance and atmospheric transmissivity by within-band and across-band shunting networks. The resulting color-processed spectral patterns are clustered to enhance the performance of a machine target detection algorithm. Psychophysicists have examined human target detection capabilities primarily via scenes of polygonal targets and distractors on uniform backgrounds. Techniques are developed and experiments are performed to assess human performance of visual search for a complex object in a cluttered scene.
The effects of amyloid precursor protein C-105 expression and ganglioside GM1 on PC12 cell vulnerability to the calcium ionophore A23 187 and hydrogen peroxide
(Boston University, 1997) O'Malley, Catherine McKeon
Specific mutations in the gene for the beta amyloid precursor protein (APP) cause Alzheimer's disease (AD). A key neuropathological hallmark of AD is extracellular neuritic plaques. The core component of plaques is AB, a 39-43 amino acid peptide derived from APP. APP C-100 and APP C-105 are C-terminal fragments of APP, 100 and 105 amino acids long, respectively. APP C-100 is a normal metabolite of APP. AI3 is located at the N-terminus of the APP C-100 sequence. To determine whether APP C-105 expression alters cellular vulnerability to calcium and hydrogen peroxide, rat PC12 cells were modified to overexpress APP C-105. Permanent transfectants (clones) were selected, then characterized by standard molecular biological techniques. DNA and mRNA corresponding to APP C-105 were detected in APP C-105 transfectants, but not in wild type controls. Aggregated APP C-105 was detected in cell lysates and conditioned media from APP C-105 transfectants, but was absent or detected at lower concentrations in vector-transfected and wild type controls. Cell survival as a function of concentration was determined for A23 l 87, a Ca^2+ ionophore, and hydrogen peroxide in APP C-105 transfectants and vector-transfected controls. Cells were exposed to A23 l 87 or hydrogen peroxide for 24 hours in RP:MI media containing 3 μM insulin, and survival was quantitated using the tetrazolium dye, MTT. APP C-105 expression significantly increased PC 12 cell vulnerability to A23 l 87, and significantly decreased vulnerability to hydrogen peroxide. Other experiments were performed with GM 1 ganglioside, which is known to protect cells against numerous insults. When wild type PC 12 cells or APP C-10 5 transfectants were exposed to a toxin and GMl concurrently for 24 hours, GMl produced concentration-dependent inhibition of A23 l 87 toxicity in wild type PC 12 cells but was ineffective against hydrogen peroxide in both wild type PC12 and APP C-105-transfected clones. The current study has demonstrated that expression of APP C-105 protects PC 12 cells against hydrogen peroxide, but exacerbates the effect of calcium influx. In conjunction with other reports, this study indicates that APP C-105 is an important regulator of cellular homeostasis. Therefore, the pattern of APP processing may alter vulnerability to neurotoxic insults.
Development of anode coating for high temperature SOM process
(Boston University, 2002) Joshi, Salil Mohan
Silicon is conventionally extracted by the carbothermic reduction process, which is energetically very inefficient, besides being harmful to the environment. The proposed Solid Oxide Membrane (SOM) process to manufacture Silicon and other metals is energy-efficient and environmentally friendly. The process and its set-up are similar to those of a conventional Solid Oxide Fuel Cell (SOFC). However, the operating temperature is much higher, and therefore, the Nickel-Zirconia cermet that is used for anode in conventional SOFCs cannot be used in this process. The present work reports the development of a suitable anode cermet coating for the purpose. Based on known physical properties of various materials and the requirements of the application, it was decided to pursue the development of an anode based on Molybdenum-Yttria Stabilized Zirconia (YSZ) cermet. Research was conducted to develop with a process to make a Molybdenum-Yttria Stabilized Zirconia cermet coating that would adhere well to the SOM substrate, which is made from YSZ and would have good electronic conductivity and porosity. The molybdenum oxide and Yttria Stabilized Zirconia mixtures were milled together and slip-cast into pellets. The variation of the cermet characteristics was studied with respect to various milling times and sintering/reduction temperatures. YSZ substrate tubes were dip-coated with slurries of made from milled mixtures of Molybdenum Oxide and Yttria Stabilized Zirconia with methanol. They were sintered and reduced in an atmosphere of Argon with five percent Hydrogen, with the intention of getting Molybdenum-Yttria Stabilized Zirconia cermet coatings. These produced flaky coatings that did not adhere to the substrate. Thus, the experiments with Molybdenum Oxide and Yttria Stabilized Zirconia mixtures demonstrated the difficulty in making the cermets by that technique. Cermet coatings were made using a slurry of Molybdenum metal and Yttria Stabilized Zirconia powder. Molybdenum powder was milled with Yttria Stabilized Zirconia and the resulting powders were made into sluITY with methanol and dip-coated onto the substrate tubes. It was seen in the cermet coatings produced that the electrical conductivity and porosity increased, whereas adherence to the substrate decreased with increasing Mo-content in the cermets. In order to make a cem1et coating that had good electrical conductivity and porosity as well as adherence to the YSZ substrate, a double-layered Molybdenum-YSZ cermet coating was made with a zirconia-rich lower layer and a molybdenum-rich upper layer. This coating had good electrical conductivity and porosity, as well as adherence. This double-layer coating was recommended as the cermet coating for use as the anode for the SOM cell.
The debates on church government at the Westminster Assembly of Divines 1643-1646
(Boston University, 1975) Smith, Paul Joseph
[The purpose of this dissertation is to analyze the debates on church government at the Westminster Assembly of Divines, 1643-1646. The major primary sources are the official minutes of the assembly and the personal memoirs of three participants: John Lightfoot, George Gillespie, and Robert Baillie. This is a historical, descriptive, and critical study. The Westminster Assembly was summoned to advise the Long Parliament on reforming the doctrine, liturgy, and government of the Church of England. For more than a year the ministers struggled to devise the best form of church government--one that would conform both to the Bible and to the practice of other Reformed churches. Their recommendations were supposed to provide the basis for parliamentary legislation on the church.]
Channeling charisma: leadership, community and ritual of a Catholic charismatic prayer group in the United States
(Boston University, 2007) Wu, Keping
This ethnographic study examines the organizational structure, formation of community and ritual performance of a Catholic charismatic prayer group in the United States. Heavily influenced by the Protestant Pentecostal movement, the Catholic Charismatic Renewal (CCR) began as a grassroots movement among the Catholic laity in the late 1960s and proposed a personal connection with God through "baptism in the Holy Spirit" and reception of "charisms," spiritual gifts, such as glossolalia (speaking in tongues), healing and prophesying. Earlier studies suggested that such groups would fade out due to the inherent tension with Catholic institutions. Nevertheless, this dissertation presents the case study of a rapidly growing Catholic charismatic group at the suburbs of Boston, with a charismatic leader who is also a priest. The research methods include participant observation of all the meetings, retreats, and rituals, formal and informal interviews of the leader, his clerical associates and members, and review of the groups' publications and the leader's own radio program, during a period of twenty months from December 2001 to August 2003. I have also visited and interviewed priests and lay people of non-charismatic Catholic churches and two Protestant Pentecostal churches in the greater Boston area. Building upon Max Weber's theory of charisma, this dissertation examines how the charismatic leader maximizes his authority by integrating both personal and institutional charisma. The vertical ties the community members cultivate with the leader and the horizontal ties they establish among themselves through narratives of conversion and healing experience reinforce group cohesion and resilience. By analyzing ritual language and bodily movement, this study argues that ritual is a communication system in which the charisma of the leader and the religious experience of the followers are embodied. This study of the actual workings of a charismatic group within the hierarchical structure of the church not only advances the relationship between charisma and institution beyond the Weberian paradigm but also situates the case study of charismatic leadership within the social and historical context of American culture at large.
A literary history of the Atlantic Monthly magazine: 1909-1929
(Boston University, 1978) Sedgwick III, Ellery
[The first purpose of this work is to present a literary history of the Atlantic Monthly between 1909 and 1929. The second is to observe the decline of the genteel tradition in American intellectual life. In 1909 Ellery Sedgwick began his twenty-eight year editorship of the magazine and gradually but thoroughly remade its editorial policy, emphasizing current affairs and supplementing belles-lettres with less formal narratives of personal experience. Sedgwick's literary tastes were relatively conservative and those of his readers, who included vieilles filles of both sexes, more so. But the magazine continued to attract serious writers. During Sedgwick's first decade he published fiction and essays by Edith Wharton, J.J. Chapman, Owen Wister, H.L. Mencken, Agnes Repplier, Gamaliel Bradford, John Galsworthy, Laurence Binyon, F.L. Lucas, John Buchan, Edward Garnett, Havelock Ellis, John Masefield, H.G. Wells and Bertrand Russell. The traditional English literary influence remained strong.]
Kala Ramnath and the Hindustani violin: status and strategy in the Hindustani musical world
(Boston University, 2009) Desai-Stephens, Anaar Iris
This work is concerned with the ways m which status is manifested, determined and altered within the Hindustani musical world of North India. This enquiry is undertaken by investigating two seemingly distinct, yet profoundly intertwined parts of North Indian classical music - the Hindustani violin and the significance of gender distinctions within Hindustani music. The 'stories' of both the Hindustani violin and of women as public performers of Hindustani classical music are inextricably tied to the larger paths of colonialism and nationalism, as they have manifested in India over the past century. At the same time, a deeper understanding of these two subjects is found in an engagement with the individuals who, through their personal actions and endeavors, have sought to shift their status within Hindustani music, thereby changing the Hindustani musical world in the process. This work is therefore grounded in the musical and social knowledge of the Hindustani violinist Kala Ramnath. Kala-ji's innovative violin technique, insights into gender differentiation within the Hindustani musical world, and articulated identity as a female Hindustani instrumentalist provide new understandings of how music, words, and personal action can affect a performer's relationship with the sociomusical world that she inhabits.
A study of the Neolithic architecture of Thessaly, Greece
(Boston University, 1982) Elia, Ricardo J.
All available evidence for architecture of the Neolithic Period in Thessaly, Greece, is assembled and synthesized. The traditional house-type concept used in previous studies is reviewed and shown to contain a number of theoretical and methodological weaknesses. A new theoretical approach is developed, which treats Neolithic architecture as an integral component of the overall cultural system, reflecting climatic conditions, building technology, social organization, household structure, religion and ideology. The existence of a separate Aceramic phase in Thessaly is questioned; the "pithouse" architecture of that phase is rejected for lack of evidence. The earliest Early Neolithic architecture appears to be a local development of rectilinear houses of wood and clay; pise, mud brick, and stone foundations were also used. Evidence for Middle Neolithic architecture is more abundant, and takes the form of house remains and clay house models. MN settlements consist of detached but closely grouped houses separated by lanes and common courts. Houses are typically small, one-room structures of square or slightly elongated plan. Mud brick on stone foundations, and pitched roofs, are typical. Households probably consisted of nuclear families. The so-called "megara" of the MN period are shown to be locally developed parched houses. The identification of the "Tsangli houses" with similar structures from Can Hasan 2B in Anatolia, and the posited migration from there into Thessaly, are rejected on the basis of an archaeological comparison of the architecture of the two sites. Limited data for the LN period suggest a shift to smaller, more nucleated settlements. Houses seem to be larger now than in the MN period; this may reflect either occupation by extended families or the existence of status distinctions. The traditional interpretation of LN Dimini as the fortified palace of a king is reconsidered in light of a discussion of the ''Homeric model" implicit in the original excavator's reasoning, and on the basis of recent excavations at that site. Remains of the Final Neolithic are extremely limited; the existence of an apsidal house at Rakhmani suggests affinities with the architecture of the early phases of the Early Bronze Age in the region.
The executable model approach: synergistic strategies for maintaining the correctness and efficiency of computer networks
(Boston University, 1989) Zinky, John Arthur
The Executable Model Approach offers an effective way to integrate performance modeling into the entire development cycle of computer networks. An executable performance model is created early in the development cycle and continues to be refined in parallel with network software. The model has special system requirements that make it a fast, inexpensive, and accurate predictor of network behavior. This predictive capability enhances Capacity Management tasks for both the design and operation of networks. The Executable Model Approach is a set of strategies that use an executable performance model to increase the correctness and efficiency of networks. The model can be used as a testbed to confirm hypotheses about network behavior and to speed up the process of troubleshooting performance faults. The model also represents an independently developed encoding of network algorithms and can be used in the fashion of N-Version programming to increase the reliability of network software. Finally, the model is instrumented with finer detail than the operational network and can be used to enhance the understanding of network behavior. Executable models have different properties than models traditionally used to design networks. Executable models are optimized for fast turn-around time and their functionality is limited to modeling a specific operational context, whereas design models have flexible functionality that allows them to explore a wide range of hypothetical networks. The mechanisms needed to create and run executable performance models were not available until the recent advances in expert systems, supercomputers, and hybrid-modeling. The feasibility of creating executable models is demonstrated by the development of an automated tool for troubleshooting performance faults. Also, the potential benefit of using executable models is analyzed in terms of increased software reliability and troubleshooting speed. The Executable Model Approach is effective because it exploits the characteristics of both computer networks and executable models. Computer networks are large, complex, and expensive systems. Methods are needed to analyze their behavior in a general and global way. Executable models automatically generate a representation of network behavior from network stimulus. They are easy to use and combine with other tools.
Reproductive limitation in coastal ospreys (Pandion haliaetus): an ecological and an evolutionary perspective
(Boston University, 1984) Poole, Alan Forsyth
Field studies of breeding ospreys were conducted in coastal regions of Massachusetts, New York, and south Florida from 1978-1983 to determine: ( i) the proximate control that local food supply exerts on reproductive performance in these populations; (ii) how food limitation has ultimately shaped life-history patterns in this species, especially clutch-size and laying date. Reduced food delivery to nests increased nestling loss. Reproductive loss was especially high in Florida where latitude and season restricted daylight foraging time for the providing male parent. Starvation of smaller, later-hatching chicks within broods was the primary cause of nestling death. Sibling aggression accounted for the preferential feeding of older nestmates, but only in food-stressed colonies. Food consumption and weight gain were measured for 18 female ospreys prior to egg-laying. Females gained little weight during this courtship period, and rates of food intake had no strong relationship to clutch or egg size in these birds. Females that laid early were better fed than those laying late, but the ages and breeding experience of pairs explained most of the variability in their laying dates. Reproductive success within local populations of ospreys declined steadily as the breeding season progressed. This pattern could not be explained by changes in clutch size or food availability and was only partially explained by changes in the age and experience of pairs. Reduced reproductive effort is discussed as an alternative explanation. Females laying modal 3-egg clutches fledged nearly as many young as those laying 4 eggs. Pairs with 4-egg clutches showed more yearly variability in reproductive success than those with clutches of 3 eggs; rarely did pairs fledge 4 young. Males in pairs given enlarged broods (5 young) increased food delivery to their nests, but the amount of food available per chick was still less than in normal 3-young broods. Females in pairs given enlarged broods ate less food and suffered potentially drastic weight loss.
A study of dynamical vortices in the Abelian-Higgs and Chern-Simons models
(Boston University, 1994) Strilka, Richard John
Vortices are common to many physical systems. Most people, for example, are familiar with eddies that form in streams and rivers. They usually have an energy density per unit length which is "localized" and, consequently, their crosssections may be thought of as "particles" in two dimensions. Theories which support stable vortex solutions are highly non-linear; and therefore, their study has relied heavily upon computer simulations. In this dissertation, I numerically explore the dynamical interactions of vortices in the (3 + 1) Abelian Higgs and (2 + 1) ChernSimons theories. Both of these models involve a complex scalar field coupled to a U (l) gauge field. I present the results of computer simulations which involve parallel vortices and anti-vortices for a wide range of parameters. For example, I show that when critically-coupled vortices collide, the scattering results are approximately velocity independent until β ∼ 0.3 and the collisions are approximately elastic until β ∼ 0.3. This implies that the higher-order modes, which can in general be excited from a collision, "decouple" from the dynamics when β ≤ 0.3. I use these results to study the metric on the moduli space M_2, calculating the metric from its field-kinetic definition. The scattering angles, calculated directly from the metric components, are shown to agree with the numerical simulations. The non-trivial form of the components are discussed in relation to the scattering results. I also discuss vortices as to their application to cosmology and numerically study a cosmic string loop collapsing under its own tension. I also study the dynamics of non-topological vortices in the (2 + 1) nonlinear gauged Schroedinger equation. For several parameters, I perform simulations of two colliding vortices, finding the scattering to be peaked in the forward direction after a vortex/vortex head-on collision. I also find that the vortices do not retain their radially symmetric shape after the collision. This suggests that the vortices are not solitons and that the collisions are inelastic. Moreover, the scattering results for collisions with non-zero impact parameters b are not symmetrical under the reflection b → −b.
The Black magazine since World War II and its background
(Boston University, 1977) Saunders, Doris E.
[This study attempts to show the growth and development of The Black magazine from its early history as an organ of protest and a repository of cultural and educational attainment on the part of free Blacks to a political propaganda tool used to enlighten and persuade a disillusioned and frightened people of their right to full and unequivocal citizenship and civil rights. The struggle for the control of the mind of the mass of Black Americans was waged in the Black newspaper and periodical press. Examination of the use of magazines such as THE VOICE OF THE NEGRO, THE HORIZON and THE CRISIS to counteract the non-resistant passivity and emphasis on materialism that was characteristic of the Booker T. Washington school of thought provides a large segment of the media's historical development. The emergence since 1945, or the end of World War II, of a periodical press that is less an initiator of protest than it is a reflection of the tastes and habits and the social and political points 6f view as expressed by a complex and multifaceted sub-culture, provide the major portion of this study. It focuses on John H. Johnson, the president and publisher of EBONY Magazine, the largest circulation general publication in the history of the periodical press. EBONY, founded in 1947, has a guaranteed circulation of 1,300~000 copies monthly. Brief sketches are given of other Black-oriented magazines published since 1945, a description given of the Black consumer market and a content analysis of 12 .consecutive issues of EBONY.]

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