The Effect of Temporal Gap on the Combination of Auditory Information

Past research has indicated different models of combination may be activated when an individual perceives information as coming from the same source (Treisman, 1998; Ernst, 2004). Moreover, auditory perception research has indicated that a temporal window of integration exists around sounds that are separated by 160 ms or less (Yabe et al, 1998). The current experiment investigated if predictions from an independent decisions model would hold when multiple sounds were played with a gap more or less than 150 ms. We hypothesized that when the gap between cues was 150 ms, the independent decisions model prediction would differ significantly from the observed data, but that a significant difference would not be found when comparing a much larger time gap condition data against the independent decisions model prediction. 36 participants completed three blocks where they were provided with either one or two auditory cues and asked to lateralize the cues to either the left or right side. Blocks differed in terms of number of cues (one or two) and time gap between the cues in the multiple cue blocks (150 ms or 500 ms). Results indicated that the 150 ms gap and 500 ms gap condition both significantly differed from the predictions of the independent decisions model. This finding implies that multiple auditory cues will be integrated in a localization task even with a gap between the cues up to 500 ms

Balancing labor requirements in a manufacturing environment

“This research examines construction environments within manufacturing facilities, specifically semiconductor manufacturing facilities, and develops a new optimization method that is scalable for large construction projects with multiple execution modes and resource constraints. The model is developed to represent real-world conditions in which project activities do not have a fixed, prespecified duration but rather a total amount of work that is directly impacted by the level of resources assigned. To expand on the concept of resource driven project durations, this research aims to mimic manufacturing construction environments by allowing a non-continuous resource allocation to project tasks. This concept allows for resources to shift between projects in order to achieve the optimal result for the project manager. Our model generates a novel multi-objective resource constrained project scheduling problem. Specifically, two objectives are studied; the minimization of the total direct labor cost and the minimization of the resource leveling. This research will utilize multiple techniques to achieve resource leveling and discuss the advantage each one provides to the project team, as well as a comparison of the Pareto Fronts between the given resource leveling and cost minimization objective functions. Finally, a heuristic is developed utilizing partial linear relaxation to scale the optimization model for large scale projects. The computation results from multiple randomly generated case studies show that the new heuristic method is capable of generating high quality solutions at significantly less computational time”--Abstract, page iv

Does Victory in This Clash Mean So Much to You? : Translating Power in Three Plays of Aeschylus

Senior Project submitted to The Division of Languages and Literature of Bard Colleg

From Dye Sensitized Solar Cells to Organic Field Effect Transistors: A Computational Investigation into the Structural and Electronic Properties of Novel Phthalocyanines

Phthalocyanines (Pc) have gained intense research attention in many diverse application areas due to their highly tunable electronic and structural properties through modification of the molecular periphery and metal center. Throughout this work a series of novel perfluoro-isopropyl substituted MPc have been investigated through theoretical methods. First, the synthetic mechanisms of these Pcs will be explored to gain insight into the experimentally observed Pc product distribution. By examining the electronic structure and formation energies of the various Pc precursors, we explain the product distribution as well as propose the formation of additional Pcs, which were not currently believed to form. The effect of metal center and peripheral modification on the Pc structural and electronic properties is also determined through a systematic investigation of several Pcs with varying degree of peripheral modification as well as several different metal centers. Increased modification of the Pc periphery with strongly electron withdrawing groups lowers the energy of the molecular frontier orbitals; increasing the chemical stability of the Pc. Open d-shell metal centers also introduce several partially occupied states near the top of the Pc valence band, which have electron density localized on the metal center. The bulky groups on the periphery of the Pc also act to mitigate molecular aggregation. To access the degree of aggregation as a function of peripheral modification, a molecular dynamics forcefield within the CHARMM parameterization model was developed specific to these Pcs. This also allows for the simulation of bulk and thin film properties important to various application areas. Finally, we propose a completely solid state dye sensitized solar cell (DSSC) design in which these chemically robust modified Pcs are sandwiched between n-TiO2 and p-NiO, acting as both photosensitizer and electron shuttle. Through analysis of the electronic structure of the Pc|semiconductor systems, the free energy associated with hole injection into the valence band of NiO upon photoexcitation of the sensitizer and electron injection into the conduction band of TiO2 from the reduced form of the Pc are calculated. Significant molecular orbital coupling between the Pc and semiconductors results in estimated charge transfer lifetimes on the femtosecond time scale on both NiO and TiO2. Additionally, the calculated excited state lifetimes of the Pc is found to be on the nanoseconds time scale, allowing ample time for charge transfer prior to the spontaneous relaxation of the Pc excited state. In the absence of a liquid electrolyte solution, the Pc molecule will need to also act as electron shuttle in our cell design. The charge transfer properties within the Marcus-Hush electron transfer theoretical framework are calculated. Results indicate that intermediate modification of the Pc periphery leads to high hole and electron mobilities. This is a promising result for our proposed DSSC design, but also makes these Pcs a viable semiconducting material in other application areas, such as light emitting diodes (LEDs) or organic field effect transistors (OFETs)

From Dye Sensitized Solar Cells to Organic Field Effect Transistors: A Computational Investigation into the Structural and Electronic Properties of Novel Phthalocyanines

Phthalocyanines (Pc) have gained intense research attention in many diverse application areas due to their highly tunable electronic and structural properties through modification of the molecular periphery and metal center. Throughout this work a series of novel perfluoro-isopropyl substituted MPc have been investigated through theoretical methods. First, the synthetic mechanisms of these Pcs will be explored to gain insight into the experimentally observed Pc product distribution. By examining the electronic structure and formation energies of the various Pc precursors, we explain the product distribution as well as propose the formation of additional Pcs, which were not currently believed to form. The effect of metal center and peripheral modification on the Pc structural and electronic properties is also determined through a systematic investigation of several Pcs with varying degree of peripheral modification as well as several different metal centers. Increased modification of the Pc periphery with strongly electron withdrawing groups lowers the energy of the molecular frontier orbitals; increasing the chemical stability of the Pc. Open d-shell metal centers also introduce several partially occupied states near the top of the Pc valence band, which have electron density localized on the metal center. The bulky groups on the periphery of the Pc also act to mitigate molecular aggregation. To access the degree of aggregation as a function of peripheral modification, a molecular dynamics forcefield within the CHARMM parameterization model was developed specific to these Pcs. This also allows for the simulation of bulk and thin film properties important to various application areas. Finally, we propose a completely solid state dye sensitized solar cell (DSSC) design in which these chemically robust modified Pcs are sandwiched between n-TiO2 and p-NiO, acting as both photosensitizer and electron shuttle. Through analysis of the electronic structure of the Pc|semiconductor systems, the free energy associated with hole injection into the valence band of NiO upon photoexcitation of the sensitizer and electron injection into the conduction band of TiO2 from the reduced form of the Pc are calculated. Significant molecular orbital coupling between the Pc and semiconductors results in estimated charge transfer lifetimes on the femtosecond time scale on both NiO and TiO2. Additionally, the calculated excited state lifetimes of the Pc is found to be on the nanoseconds time scale, allowing ample time for charge transfer prior to the spontaneous relaxation of the Pc excited state. In the absence of a liquid electrolyte solution, the Pc molecule will need to also act as electron shuttle in our cell design. The charge transfer properties within the Marcus-Hush electron transfer theoretical framework are calculated. Results indicate that intermediate modification of the Pc periphery leads to high hole and electron mobilities. This is a promising result for our proposed DSSC design, but also makes these Pcs a viable semiconducting material in other application areas, such as light emitting diodes (LEDs) or organic field effect transistors (OFETs)

Responding to natural disasters: Examining identity and prosociality in the context of a major earthquake

How does a major natural disaster relate to individuals’ orientation towards society? We collected repeated cross‐sectional surveys before (n = 644) and after the 2010 Chile earthquake (n = 1,389) to examine levels of national identity, prosocial values, helping motivations, and prosocial behaviours in the context of such a calamitous societal event. Our research questions, derived from the literature on helping in times of crisis, considered how natural disasters may implicate identity and prosociality, as well as how identity, prosocial values, and motivations are linked to prosocial action after a disaster. Higher levels of national identity, helping motivations, and disaster‐related helping were found after the earthquake, suggesting that in the aftermath of a disaster, people unite under a common national identity and are motivated to take action related to disaster relief. National identity and prosocial values were closely linked to helping after the earthquake, but specific helping motivations rarely predicted prosocial behaviours. Additionally, proximity to the epicentre was related to higher levels of national identity and participation in reconstruction efforts. These findings contribute to our understanding of people's responses to natural disasters and suggest ways of encouraging prosocial behaviour in the aftermath of unexpected tragic events

Gratitude as Persuasion: Understanding When and Why Gratitude Expressions Facilitate and Inhibit Compliance

University of Minnesota PhD dissertation. August 2015. Major: Psychology. Advisors: Mark Snyder and Alexander Rothman. 1 computer file (PDF): vii, 127 pages.Most of the research examining the influence of gratitude expressions on compliance has focused on their benefits, but some empirical and anecdotal evidence suggests that they can both facilitate and inhibit compliance with requests. This dissertation seeks to understand when and why gratitude expressions enhance compliance and also when and why they may lead to diminished compliance. Two online experiments of adult participants tested hypotheses based on self-determination theory and the persuasion knowledge model. Motivation type and persuasion awareness were hypothesized to moderate the influence of gratitude expressions on compliance, and perceptions of sincerity, basic need support, and differences in state motivation were hypothesized to mediate these effects. Results suggest that gratitude expressions increase compliance through affecting perceptions of sincerity and by supporting relatedness needs. However, results also suggest that gratitude expressions do not always enhance compliance, and can sometimes lead to diminished compliance. Motivation type and persuasion awareness were both found to moderate the influence of gratitude expressions on compliance, and these effects were mediated by differences in state motivation. This research broadens our understanding of gratitude in social contexts by showing that expressions of gratitude can not only facilitate compliance with requests, but also sometimes lead to reductions in compliance. It demonstrates when each of these outcomes is more likely to occur, and it also contributes by uncovering some of the psychological dynamics underlying these influences

Spatial estimation of herbaceous biomass using remote sensing in Southern African savannas

The Savanna biome covers around 60% of sub-Saharan Africa. The goods and services it provides are utilised and often depended upon by rural communities, commercial farmers and managers of conservation areas existing within it. The benefits derivable by these parties depend largely on vegetation structure and species composition which can show great variation within savannas. Fire has long been used as an effective means of manipulating savanna vegetation to maximise the provision of specific benefits, usually the provision of new herbaceous growth, and to a lesser extent to control woody cover. Information on the abundance and distribution of herbaceous biomass, which is the primary fuel source for savanna fires, has emerged as one of the most important inputs for savanna management planning. Although the most popular and reliable means of obtaining this information remains field-based sampling, estimation using remote sensing data is increasingly being incorporated into the process. Its increased popularity stems from the fact that it can greatly expand the extent of the areas for which herbaceous biomass estimations can be provided. Although there have been studies conducted on the performance of individual remote sensing based herbaceous biomass estimation methods, few have focused on the relative performance of available methods. Information on the accuracy of methods when applied in relatively densely wooded savannas, or those where a large amount of herbaceous material is retained between seasons is also limited. This presents a problem for savanna managers in South Africa where these conditions prevail. It was the aim of this study to compare the accuracy and precision of two different remote sensing based herbaceous biomass estimation techniques (the use of a regression model and cokriging) when applied under such conditions. To achieve this aim a large amount of herbaceous biomass data were required to form testing and training datasets. These were acquired from the Kruger National Park’s Veld Condition Assessment (VCA) datasets for the growth seasons between 2000 and 2006, which contains herbaceous biomass estimates based on disk pasture meter readings. It was suspected early on in the study that the VCA field data was not ideal for use as remote sensing (ground truthing) field data because of the limited size of the field plots relative to the pixels of the remotely sensed imagery used. It was decided to include an additional section of analysis to determine the possible contribution of this issue to the estimation error of the methods assessed. This involved measuring and comparing mean herbaceous biomass in co-located trial 60x60m VCA sites and trial 250x250m, The Moderate Resolution Imaging Spectroradiometer (MODIS) pixels. The main section of analysis involved (i) gathering and deriving the required variables for use in the two estimation methods assessed, (ii) producing the estimates and (iii) comparing their accuracy and precision. The first method assessed was the use of a linear regression model. Seven regression models were created in total, one for each year of the growth seasons occurring between 2000 and 2006, plus another using all of the data combined. The models included variables to account for vegetation production (based on MODIS EVI), tree cover and fire history. These variables were derived using data supplied by the CSIR and Kruger National Park Scientific Services. The second method assessed was cokriging performed with the VCA herbaceous biomass field estimates as the primary variable and the MODIS EVI data as a secondary variable. The regression models were unable to account for more than 46% of the variation in herbaceous biomass, usually accounting for between just 20 and 30% (R2 of between 0.2 and 0.3). Three potential methods were identified that could improve the model fits obtained in the future, namely: 1. Increasing the dimensions of the field sample plots 2. Improving the calibration of the disk pasture meter used to collect the field data 3. Using EVI from previous seasons in conjunction with fire scar data to account for the presence of dry material from previous seasons. Cokriging produced estimates that were on average 119 kg/ha more accurate than those of the regression models. However, the performance of cokriging was poorer than expected given the results of previous studies in the area. A possible explanation for this discrepancy is that the ArcGIS geostatistical analysis extension used in this study is limited in its capabilities. Even with the poorer than expected performance recorded in this study, the cokriged maps remain the best option for fire managers as they are the most accurate to date and require the fewest resources to produce. Neither method produced estimates with less than 1000 kg/ha of error (RMSE), the upper limit initially considered useful in this study. However this error limit could be considered unrealistic given the well documented high level of heterogeneity typical of southern African savannas

When does activism benefit well-being? Evidence from a longitudinal study of Clinton voters in the 2016 U.S. presidential election

Contrary to the expectations of many, Hillary Clinton lost the 2016 U.S. presidential election. The initial shock to her supporters turned into despair for most, but not everyone was affected equally. We draw from the literature on political activism, identity, and self-other overlap in predicting that not all Clinton voters would be equivalently crushed by her loss. Specifically, we hypothesize that pre-election measures of political activism, and level of self-other identification between participants and Clinton-that is, how much a person was "with her"-will interact to predict the level of distress of Clinton voters two months later. Longitudinal data support our hypothesis. Notably, among Clinton voters, greater activism negatively predicted depressive symptoms, and positively predicted sleep quality, but only when participants were highly identified with Clinton. We discuss the implications of the results for theory and research on social action and well-being