2,576 research outputs found
Charitable Giving by Married Couples: Who Decides and Why Does it Matter?
We examine how charitable giving is influenced by who in the household is primarily responsible for giving decisions. Looking first at single-person households, we find men and women to have significantly different tastes for giving, setting up a potential conflict for married couples. We find that, with respect to total giving, married households tend to resolve these conflicts largely in favor of the husband's preferences. Bargaining over charitable giving, rather than letting one spouse take charge, reduces giving by about six percent. When the woman is the decision maker, she will still make a significantly different allocation of those charity dollars, preferring to give to more charities but to give less to each. Our results give new insights into both the demographics of charitable giving and the costliness of household bargaining.
Radiometric Correction of Observations from Microwave Humidity Sounders
The Advanced Microwave Sounding Unit-B (AMSU-B) and Microwave Humidity Sounder (MHS) are total power microwave radiometers operating at frequencies near the water vapor absorption line at 183 GHz. The measurements of these instruments are crucial for deriving a variety of climate and hydrological products such as water vapor, precipitation, and ice cloud parameters. However, these measurements are subject to several errors that can be classified into radiometric and geometric errors. The aim of this study is to quantify and correct the radiometric errors in these observations through intercalibration. Since the bias in the calibration of microwave instruments changes with scene temperature, a two-point intercalibration correction scheme was developed based on averages of measurements over the tropical oceans and nighttime polar regions. The intercalibration coefficients were calculated on a monthly basis using measurements averaged over each specified region and each orbit, then interpolated to estimate the daily coefficients. Since AMSU-B and MHS channels operate at different frequencies and polarizations, the measurements from the two instruments were not intercalibrated. Because of the negligible diurnal cycle of both temperature and humidity fields over the tropical oceans, the satellites with the most stable time series of brightness temperatures over the tropical oceans (NOAA-17 for AMSU-B and NOAA-18 for MHS) were selected as the reference satellites and other similar instruments were intercalibrated with respect to the reference instrument. The results show that channels 1, 3, 4, and 5 of AMSU-B on board NOAA-16 and channels 1 and 4 of AMSU-B on board NOAA-15 show a large drift over the period of operation. The MHS measurements from instruments on board NOAA-18, NOAA-19, and MetOp-A are generally consistent with each other. Because of the lack of reference measurements, radiometric correction of microwave instruments remain a challenge, as the intercalibration of these instruments largely depends on the stability of the reference instrument
Charitable Giving by Married Couples: Who Decides and Why Does it Matter?
We examine how charitable giving is influenced by who in the household is primarily responsible for giving decisions. Looking first at single-person households, we find men and women to have significantly different tastes for giving, setting up a potential conflict for married couples. We find that, with respect to total giving, married households tend to resolve these conflicts largely in favor of the husbandâs preferences. However, when the woman is the decision maker, she will still make a significantly different allocation of those charity dollars, preferring to give to more charities but to give less to each. We find our results give new insights into both issues of charitable giving and household decision making.
Charitable Giving by Married Couples: Who Decides and Why Does it Matter?
We examine how charitable giving is influenced by who in the household is primarily responsible for giving decisions. Looking first at single-person households, we find men and women to have significantly different tastes for giving, setting up a potential conflict for married couples. We find that, with respect to total giving, married households tend to resolve these conflicts largely in favor of the husband's preferences. However, when the woman is the decision maker, she will still make a significantly different allocation of those charity dollars, preferring to give to more charities but to give less to each. We find our results give new insights into both issues of charitable giving and household decision making.
A study of roman gold coins found its Britain and their implications
My research has centred around two objects, namely a study of the longevity of aurei and a consideration of the economy, political and social life of Roman Britain in so far as this can be deduced from the evidence of gold coin distribution. The results have been concrete enough in the first category to justify the claim that aurei circulated for many years as a rule. Results in the second and more diverse section of my thesis have necessarily led to more tenuous and debatable conclusions and opinions. It has been possible to collect statistics on the distribution of Roman gold coins in Britain from which I have deduced a series of theories regarding the economic, political and social spheres of Roman Britain at various stages in the provinceâs history. Hoards and site-finds have been studied in isolation and together in order to gain all possible information. Geographical distribution seems fairly even over the whole country with a moderate bias towards bulk-volume in the south-east. North-south differentials exist at all periods and appear to fluctuate with military movements and economic growth and decline, both of which are of prime importance in studying this distribution pattern, I have also considered gold coins from Ireland and gold pieces used for jewellery. These two topics form brief appendices to the main theme of the thesis and serve to illustrate something of its width. A final appendix discusses the use of numismatic evidence by Sir George Macdonald and evaluates some of his methods
University of Missouri as a centralizing factor in the educational activities of the state
TypescriptM.A. University of Missouri 1910In many lines of activity to-day, there is a strong tendency toward centralization, for organization is a great solvent of waste. In the business world this has resulted in the corporations of the country. In the state it has led to a strong central government. In the social world it has resulted in the organization of clubs and societies for the purpose of forwarding any social movement that interests any particular locality. This centralizing tendency as manifested in the various industrial, governmental and social activities of to-day is also affecting educational activities. The school as the institution of society for making its members efficient in social life is not as effective as it should be. This is evident from the fact that many children leave school at an early age, and so the loss to the state due to the failure of these children to complete their school work is very great. That many children do leave school sooner than they should is, in a large measure, a result of the lack of uniformity in the standards of education, the overlapping of school work where pupils pass from one locality to another and a lack of the proper correlation of the different classes of public schools. The purpose of this paper is to trace historically (1) the origin of the common schools in Missouri and the important stages of their development to the time when they first came under the influence of the university, (2) the origin of the university and the most important stages of its development to the time when it began to influence the common schools of the state, and (3) the leading influences toward centralization that have been exerted by the university upon the common schools together with the results thus far accomplished.Includes bibliographical reference
Mechanical characterization of MEMS bi-stable buckled diaphragms.
Bi-stable buckled MEMS (micro-electromechanical systems) diaphragms have a myriad of uses in the MEMS field for their large out-of-plane deflections. Buckling is a phenomenon brought upon by a compressive stress. Diaphragms are large aspect ratio, circular structures similar to membranes, where the thickness of the diaphragm is much smaller than its diameter. Diaphragms differ from membranes by the amount of bending stiffness. Membranes have negligible bending stiffness and are a common structure analyzed in mechanics of materials, whereas diaphragms have much larger stiffness. Diaphragms were created in the cleanroom by thermally growing silicon dioxide on a silicon wafer. A structural polyimide layer was added on top of the silicon dioxide. The created diaphragms demonstrate bi-stability, meaning that they can be switched either up or down using an applied pressure. After the pressure is removed the diaphragms remain in their new respective states. The pressure required to switch the membranes is known as the actuation or snap-through pressure, and is of primary interest. The vertical displacement of the center of the diaphragms, known as the buckled height, is also of interest. A finite element model of the diaphragm was created using ANSYS. This model was used to generate both actuation pressure and buckled height data. These two data sources are compared extensively in an attempt to further understand the behavior of the experimental system. Buckled height data between experimental data and the finite element model were found to match well. This information can be used in the production of micro-valves and micro-actuators in the future. Actuation pressure found from the finite element model follows the trend and closely models the values of experimental data for a range of membranes. Other effects not accounted for in the finite element model probably contribute to the difference between the two
Te Whare Whakakotahi : Nuturing human potential with Aroha: A thesis submitted to partial fulfilment of the requirements for the degree of Masters of Resources Studies at Te Whare WÄnaka o Aoraki Lincoln University
MÄori experience of service delivery, education programme development and resource allocation at Te Whare WÄnaka o Aoraki/Lincoln University vary in degree across a continuum of negative to positive. The social milieu of dynamic tertiary institutional environments, local, national and global forces impacting how those institutions determine their delivery of service and prevalent Aotearoa/New Zealand issues regarding MÄori access, retention and academic success in tertiary education shape the relationships and degree of authentic participation in tertiary activity for MÄori students. MÄori students of Te Whare WÄnaka o Aoraki/Lincoln University have personal and collective choices to make in relation to their academic responsibilities/ response-abilities in context to these forces and impacts.
The discourse of MÄori access to participatory democracy as it relates to Te Whare WÄnaka o Aoraki/Lincoln University binds takata whenua of this area to that institution. MÄori student access to that discursive process remains marginal. Despite that discrepancy precedence for holistic community beyond the rhetoric of discourse abounds as example throughout the coevolutionary history /herstory of the whÄnau of Te Whare Whakakotahi and Te Whare WÄnaka o Aoraki/Lincoln University over the last decade.
The rhetoric of participatory democracy is transcended through the autonomous expression of tikaka MÄori manifested in proactive processes of whakawhanaukataka via the conduit of Aroha ki te takata. Though issues of marginalisation, hegemony and dis-empowerment still impact MÄori student welfare here at Te Whare WÄnaka o Aoraki/Lincoln University, their commitment to practicing living the living practice of Tikaka MÄori specific to their needs serves to inculcate and perpetuate self autonomous values that do not require the justification and affirmation of external forces. The result of this has been the continued support and perpetuation of community wide positivity experienced by people of multiple cultures, throughout the decade, nurturing trans-cultural relationships the implicit outcome of practicing tikaka MÄori Illustrating the we-dentity potential of whÄnau as being able to encompass local, national and international dimensions highlights great opportunity for an integrated united community inclusive of takata whenua, academic staff, and students of diverse origins sharing dynamic personal gifts and abilities that have the potential to affect positive outcomes for authentic community beyond rhetoric. Though the whÄnau of Te Whare Whakakotahi have been successfully manifesting this potential over the last decade this vision is yet to be realised to its utmost degree by the stakeholders of Te Whare WÄnaka o Aoraki/Lincoln University. Te Awhioraki has shown the way, the challenge remains for Te Whare WÄnaka o Aoraki/Lincoln University to participate authentically in the future of MÄori student and wider community evolution in the next millennium. How will you respond
An Integrated Optical Pressure Sensor in the GaAs/AlGaAs Ternary System
The principal concerns of this thesis are the design, fabrication and demonstration of an optical pressure sensor in the aluminium gallium arsenide (AlGaAs) ternary epitaxial layer system. The device is based on a ridge optical waveguide traversing a section of GaAs wafer which has been wet-chemically etched, in a well-defined area, from the wafer base, through the substrate (approximately 400um thick) to within approximately 10um of the top surface of the wafer. A deflection of the membrane from equilibrium by a pressure differential across its thin dimension results in a stress-induced change in the refractive index of the membrane material. A guided wave on the top surface of the membrane experiences a change of phase as it passes through the stress field produced by the membrane deformation. A mathematical theory of photoelasticity is developed to model the deflection and stress-induced refractive index changes of a membrane of material in the zinc-blende cubic crystal class (43m), of which GaAs is a member. The theoretical model was firstly tested by measuring the deflection of membranes under pressure by observing them in a microscope equipped with a Tolansky interferometer. Using the experimental apparatus described in this thesis, membrane deflection was achieved by evacuating one side of the membranes. This resulted in the pressure being limited to one atmosphere across a membrane (or limited by the evacuating capability of the vacuum pump). Two types of device are investigated -the first uses only straight waveguides and is here referred to as a birefringent pressure sensor while the second incorporates a Mach-Zehnder waveguide structure. (1) The birefringent pressure sensing device was fabricated and tested. It consisted of a number of straight waveguides crossing a membrane and was placed in an external Mach-Zehnder interferometer in order to measure the phase-shift of light in the waveguide when a uniform pressure was applied to one surface of the membrane. The theoretical model indicates that the change in phase for TE and TM polarisations is different i. e there is stress-induced birefringence. Thus linearly polarised light launched into a straight waveguide (equally exciting the TE and TM polarisations) experiences a change of polarisation with pressure. The polarisation of the light output by the device could be monitored without placing the device in an external interferometer -hence the name 'birefringent pressure sensor'. This sensor was studied using both the techniques described above. (2) The design considerations for a waveguide Mach-Zehnder interferometric pressure sensor are based on both the photoelasticity model developed in this thesis and the results obtained from the birefringent pressure sensor. The device parameters were chosen to allow at least 2pi phase-shift (i. e one cycle) within the one atmosphere pressure limit in this thesis. The arm separation of the Mach-Zehnder structure is 300um and the total device length is about 17mm. The Y-junctions are symmetric and are formed by two intersecting S-bends of radius of curvature 40mm. The arm separation and S-bend radii are limited by the losses of the device. Theoretical calculations indicate that considerably smaller radii for the S-bends would be acceptable with only a small reduction in optical transmission. In order to estimate the losses, the transmission of the Mach-Zehnder waveguides was compared to those for straight waveguides of the same overall length. The Y-junction structures forming the Mach-Zehnder waveguide configurations were also fabricated individually in order to assess the losses relative to straight guides. The results have been compared to theoretical models of the losses in S-bends and Y-junctions. The fabrication methods for waveguides and membranes are described. Straight waveguides, Y-junction and Mach-Zehnder waveguide structures were fabricated by both Reactive Ion Etching and wet-chemical etching and a comparison of the propagation characteristics is given. Dry etching was not used for membrane fabrication mainly due to the extensive etching depths required to form membrane structures (several hundred microns). In addition wet-chemical etching was more readily available and better developed for selective etching which allowed greater control over the thickness of the membranes
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