570 research outputs found
Phase delay astrometry and its geodetic applications
The accuracy inherent in the fringe phase in the determination of source positions was calculated. It is shown that accuracy can be utilized by applying differencing techniques in order to circumvent such systematic effects as clock drift and delay due to the propagation media
The effect of potash fertilization on mineral composition, yield, and stalk breakage in corn at different nitrogen levels
Variety, climate, soil treatment, and soil composition are believed to be the principal factors causing variation in yields, composition, and stalk breakage in corn but the specific effects of each factor are not well understood. Although when all but one of these factors are controlled it should be possible to determine definite relationship between variations in this factor and plant growth and composition, relatively relatively such relationships have been established. The interrelations among soil fertility status, crop yield, plant composition, and growth habits on specific soils should be known for more efficient soil management and fertilizer use.
As a contribution to this general objective, the objectives of the present research have been to;
(1) to study the influence of time and rate of potassium fertilization on yield and amount of stalk breakage in corn at different nitrogen levels.
(2) to determine the effect of time and rate of potassium application on the potash and calcium composition of a com hybrid
Experiments on bureaucrat behaviour and public participation
Public participation mechanisms, government-initiated forms of interaction that take place outside the formal electoral process, have been heralded as a potential solution to a lack of popular trust in, engagement and satisfaction with democracy. They have proliferated in their form and use over the last two decades; a development supported by a belief that they help to increase policy effectiveness and promote democratic values. Bureaucrats largely manage public participation processes and thus have ample room to influence their outcomes. It however remains unclear to what extent bureaucrats are responsive to citizen input provided through such mechanisms and what that means for the promises entailed in public participation processes. In a series of experiments, this thesis set out to test what drives bureaucratic responsiveness to citizen input, and what types of government communications can help to increase the number and diversify the composition of citizen groups who take part in public participation processes. In Chapter 2, I use a field experiment with 7,000 bureaucrats to establish to what extent bureaucrats are responsive, and whether interventions targeted at increasing their motivation to engage with citizen input can alter such responsiveness. In Chapter 3, a survey experiment tests how bureaucrats respond when the quality of citizen input varies. More specifically, it evaluates how bureaucrats respond when politicians are opposed to heeding citizen demands, and how this compares to when politicians support policy change demanded through public participation mechanisms. Finally, Chapter 4 addresses the question of input quality from the supply-side. In a field experiment targeting over twenty-nine thousand households, I test whether government communications can increase and diversify turnout for public participation processes. The evidence deriving from this research project shows (i) that motivational rather than time and task related factors drive bureaucrat responsiveness to citizen input; illustrates (ii) how conflict of citizen and political principals causes changes in the willingness of bureaucrats to implement policy and (iii) that behavioural nudges demonstrated to be effective in the Get-Out-The-Vote literature backfired in the context of non-electoral participation. The findings challenge the normative claims of public participation literature and contribute to the theory of the political control of the bureaucracy by providing causal evidence for the importance of motivational and contextual factors in determining bureaucrat behaviour
Vertical phasing in commercial real estate development
Thesis (S.M. in Real Estate Development)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, Center for Real Estate, 2008 [first author]; and, (S.M. in Real Estate Development)--Massachusetts Institute of Technology, Dept. of Architecture, Center for Real Estate, 2008 [second author].Includes bibliographical references.Real estate development is inherently a risky endeavor. Developers encounter varied risks during the different phases of a development project, from permitting to construction and through lease-up and stabilized operations. Flexibility allows a developer to mitigate some of these risks by capitalizing on potential upsides, and reducing the effects from possible downsides. Flexibility, and phasing specifically, enables a developer to manage risk more effectively by allowing a building to grow as market conditions warrant. This thesis investigates the determinants and implementation of vertical phasing, and suggests areas of applicability for vertically phased development. By "vertical phasing", we mean when a building is originally constructed to a certain height, but includes the intentional capacity for it to expand vertically in the future. Vertical phasing is an example of a real option "in" real estate development. A real option embodies a right, but not an obligation to pursue a future course of action. Flexibility, or real options, in real estate is important because it can add value to a project. The significant expansion of tall buildings is a recent phenomenon, though vertical phasing itself is not new. Expanding a one story building to two stories, for example, is a common example of vertical phasing. This thesis examines the decision and development process of major buildings that are constructed with the intentional ability to be expanded vertically in the future without disrupting the occupation and operations of the original building. While the intention is that the vertical expansion will take place at some appropriate time in the future, if such an opportunity never arises, the original building can exist by itself as a complete, fully functioning structure.(cont.) Drawing from a study of four buildings in the United States and Canada, this thesis examines the context in which vertical phasing of buildings is employed. It first considers the various drivers that lead to vertical phasing. It then discusses the specific issues and challenges with respect to vertical phasing. This thesis argues that while vertical phasing of buildings is rare and complex, it is a viable method of development that has significant potential in enhancing the value of buildings. Specifically, vertical phasing is relevant to corporate real estate development, in which less quantifiable value drivers of a building are tangible and important. By evaluating the drivers and implementation of vertical phasing, this thesis shows that vertical phasing of buildings may be easier than commonly believed, and may be used effectively in corporate real estate development and possibly other sectors of the real estate industry.by Jason R. Pearson and Kate S. Wittels.S.M.in Real Estate Developmen
Heart Rate Variability as a Possible Predictive Marker for Acute Inflammatory Response in COVID-19 Patients
ABSTRACT Introduction Increases in C-reactive protein (CRP) are used to track the inflammatory process of COVID-19 and are associated with disease state progression. Decreases in heart rate variability (HRV) correlate with worsening of disease states. This observational study tracks changes in HRV relative to changes in CRP in COVID-19 patients. Materials and Methods In accordance with an Institutional Review Board-approved study, 17 patients were followed using the wearable, noninvasive Tiger Tech Warfighter Monitor (WFM) that records HRV from a single limb electrocardiogram. Intermittent, daily short-segment data sets of 5 to 7 minutes over a minimum of 7 days were analyzed. Changes in HRV were compared to changes in CRP. Results Decreases in HRV of greater than 40% preceded a 50% increase in CRP during the ensuing 72 hours in 10 of the 12 patients who experienced a dramatic rise in CRP. The effectiveness of HRV as a leading indicator of a rise in CRP was evaluated; the sensitivity, specificity, positive predictive value, and negative predictive value for 40% decreases in HRV preceding 50% increases in CRP were 83.3%, 75%, 90.9%, and 60%, respectively. Conclusion Substantial decreases in HRV preceded elevations in CRP in the ensuing 72 hours with a 90.9% positive predictive value. Early detection of increasing inflammation may prove vital in mitigating the deleterious effects of an abnormal inflammatory response, particularly in COVID-19 patients. This capability could have a major impact in triage and care of moderate to severe COVID-19 patients in major medical centers as well as field hospitals. This study demonstrates the potential value of short-segment, intermittent HRV analysis in COVID-19 patients
A thermo-chemical analysis of some amphiboles
Thesis. (Ph.D.) Massachusetts Institute of Technology. Dept. of Geology, 1951.Vita.Bibliography: leaves 116-119.by Mark Caesar Wittels.Ph.D
Tectonic overpressure in Franciscan terrains.
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Geology and Geophysics, 1969.Bibliography: leaves 24-25.M.S
Positions and kinematics of quasars and related radio objects inferred from VLBI observations.
Thesis. 1975. Ph.D.--Massachusetts Institute of Technology. Dept. of Physics.Bibliography: leaves 189-194.Ph.D
Electron Optics
Contains research objectives, summary of research on one research project, and reports on two research project.Joint Services Electronics Program (Contract DAAB07-74-C-0630
Good Arms and Good Laws: Machiavelli, Regime-Type, and Violent Oppression
<p>The problem of violent oppression is a persistent one. Every regime - autocratic or democratic - has an obligation to prevent the violent oppression of its citizens. My dissertation "Good Arms and Good Laws: Machiavelli, Regime-Type, and Violent Oppression" uses Machiavelli's understanding of different regime-types and their political dynamics to explore the means by which democracies and autocracies alike can prevent violent oppression within their borders. My exploration produces a standard for praiseworthy political regimes and action, based on what Machiavelli identifies as the people's desire "not to be oppressed."</p><p>Machiavelli's analysis of this problem of political violence leads to the conclusion that all types of regimes are united in needing an interdependent, yet competitive political relationship between their leading political figure(s) and the people at large. Different kinds of regimes vary, however, in the roles that their primary political classes must play in order to prevent oppression within their borders. After using the Florentine Histories to identify the lines of thinking central to Machiavelli's work, in chapter 1 I turn to Machiavelli's discussion of the citizen-militia in The Art of War. In chapters 2 and 3, I detail Machiavelli's recommendations for praiseworthy principalities in the Prince, where Machiavelli actually exhorts princes to arm their people (chapter 2) while simultaneously crafting for them the political ethics for which the text is notorious (chapter 3). In Chapters 4 and 5, I detail Machiavelli's recommendations for praiseworthy republics in the Discourses on Livy, where Machiavelli charges the people with policing the elites that would engage in projects of oppression if left to their own devices (chapter 4) while simultaneously praising elites who help to create and maintain mechanisms of violence (chapter 5). Machiavelli's analysis compels us to recognize that it is the particulars of these interdependent, yet competitive relationships between the people and their leading political figure(s) that define a regime and that our praise of that regime ought not depend categorically on whether the people rule, but rather whether the a regime's political classes effectively cooperate to prevent violent oppression.</p>Dissertatio
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