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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

Diversifiering : Fastighetsfinansiering i skymningen av Basel III / Diversification : Real Estate Finance in the Twilight of Basel III

Prakash, Gyan, Oscar, Swanberg January 2021 (has links)
Finanskrisen 2007-2008 blev startskottet för nya bankregleringar och åtstramningar.Regelverket Basel III introducerades med syfte att hantera risker bättre genom att införahårdare kapital- och likviditetskrav som i sin tur skulle motverka eventuella nya systematiskarisker. Syftet med denna uppsats är att undersöka Basel III:s påverkan på diversifieringen avfastighetsfinansiering på den svenska marknaden och utreda de drivkrafter och effekter avdessa förändringar. Studien ämnar att ge ett brett perspektiv genom att undersöka påverkan påett flertal sektorer i den empiriska undersökningen. Efter genomförandet av studien så kan det konstateras att bankerna har fått ökade kostnadersom sedermera har förskjutits till kunderna. Vidare har belåningsgraderna i fastighetssektornminskat till följd av implementeringen Basel III. Det nya regulatoriska landskapet har banat väg för diversifiering. Dock, så kan de primäradrivkrafterna tillskrivas makro-sentiment, jakt på avkastning, market timing och aktörer somhar vuxit ifrån sitt beroende av bankkapital. / The financial crisis of 2007-2008 was the start of new banking regulations and austeritymeasures. Basel III was introduced with the intent of managing risks better by introducingstricter capital and liquidity requirements. The new requirements would in return counteractany new systematic risks. The purpose of this study is to investigate Basel III’s impact oncredit diversification on the Swedish market and navigate what the driving forces are and theeffects of regulatory change. The aim is to provide a broad perspective by presenting valuableinformation relevant to the subject and examining the impact of these changes on differentsectors. The results of the study shows that new regulations have entailed a major regulatory changewith subsequent implications on the market. Findings also show that banks have experiencedan increase of costs which have since been shifted to customers. Furthermore, loan-to-valueratios within the real estate sector have decreased as a result of the implementation of BaselIII. The new regulatory framework has paved the way for diversification. However, thedevelopment has been propelled by macro sentiment, reaching for yield-behavior, markettiming and firms outgrowing their dependency on bank capital.
332

Implementierung und Validierung eines Monte-Carlo-Teilchentransport-Modells für das Prompt Gamma-Ray Timing-System

Urban, Konstantin 30 January 2024 (has links)
Die Protonentherapie zeichnet sich durch steile Dosisgradienten und damit einen gut lokalisierbaren Energieübertrag aus. Um dieses Potential voll ausschöpfen zu können, werden weltweit Möglichkeiten erforscht, die Dosisdeposition und insbesondere die Reichweite der Protonen im Patienten zu verifizieren. Eine vielversprechende, erst im letzten Jahrzehnt entdeckte Methode ist das Prompt Gamma-Ray Timing (PGT), das auf der Abhängigkeit der detektierten Flugzeitverteilung prompter Gammastrahlung von der Transitzeit der Protonen im Patienten beruht. In dieser Arbeit wird eine Geant4-Simulation zur Vorhersage der PGT-Spektren bei Bestrahlung eines PMMA-Phantoms entwickelt und durch den Vergleich mit experimentellen Daten validiert. Sowohl die Emissionsausbeute prompter Gammastrahlung im Phantom als auch die Detektionsrate werden abhängig von der Protonenenergie analysiert. Zur Vergleichbarkeit mit den gemessenen Spektren wird eine mehrschrittige Prozessierung der Simulationsergebnisse vorgestellt. Schließlich wird die Simulation genutzt, um die Sensitivität der PGT-Methode auf Reichweitenänderungen zu demonstrieren. Dafür können in das Phantom Cavitäten unterschiedlicher Dicke und verschiedenen Materials eingefügt werden. Für geeignet gewählte Verteilungsparameter der simulierten PGT-Spektren wird deren detektierte Änderung mit der bekannten induzierten Reichweitenänderung ins Verhältnis gesetzt. Die so bestimmte Sensitivität ist mit früheren Ergebnissen für gemessene Spektren im Rahmen der Unsicherheiten in Übereinstimmung.:1 Einleitung und Motivation 1 2 Theoretische Grundlagen 5 2.1 Wechselwirkung von Protonen mit Materie 5 2.1.1 Bethe-Bloch-Gleichung 6 2.1.2 Reichweite im CSDA-Modell 9 2.1.3 Tiefendosiskurve und Bragg-Peak 10 2.2 Prompt Gamma-Ray Timing 11 2.2.1 Emission prompter Gammastrahlung 11 2.2.2 Korrelation zur Protonen-Reichweite und Dosisdeposition 11 2.2.3 Idee des Prompt Gamma-Ray Timings 14 3 Material und Methoden 17 3.1 Dresdner IBA-Protonentherapie 17 3.1.1 Beschleunigungsprinzip des Isochronzyklotrons 17 3.1.2 Zeitliche Struktur der Protonen-Pakete 18 3.2 Teilchentransportrechnungen mit Geant4 20 3.3 PLD-Format für Pencil-Beam-Scanning-Pläne 21 3.3.1 Geometrische Definition der Spots 21 3.3.2 Dosimetrische Definition der Spots 23 3.3.3 Verwendete Bestrahlungspläne 24 3.4 Messaufbau zur experimentellen Validierung 26 3.4.1 Target – PMMA-Phantom mit verschiedenen Cavitäten 27 3.4.2 Detektoren – CeBr3-Szintillatoren mit Photomultipliern 27 4 Ergebnisse und Diskussion 29 4.1 Simulierte Emission prompter Gammastrahlung 29 4.1.1 Simulierte Emissionsspektren 29 4.1.2 Simulierte Emissionsprofile 30 4.1.3 Totale Emissionsausbeute 31 4.2 Simulierte Detektion prompter Gammastrahlung 33 4.2.1 Detektionsrate und Raumwinkeleffekt 33 4.2.2 Simulierte PGT-Spektren 35 4.2.3 Simulierte Energiespektren 37 4.3 Vergleich simulierter und gemessener Spektren 39 4.3.1 Nachverarbeitung der Simulationsergebnisse 40 4.3.2 Auswahl des Energiefensters 45 4.3.3 Empirisches Modell zur Beschreibung der Zeitspektren 47 4.3.4 Diskussion systematischer Abweichungen 49 4.4 Sensitivität der Simulation gegenüber induzierten Reichweitenänderungen 51 5 Zusammenfassung und Ausblick 59 Anhang 61 A Parameter des Messaufbaus 61 B Angepasste Modellparameter aus Abbildung 4.12 62 C Sensitivität auf Reichweitenänderung bei 162 MeV 63 Literaturverzeichnis 69 / Proton therapy is characterized by steep dose gradients and thus a well-localizable energy transfer. To fully harness this potential, possibilities are being explored worldwide to verify the dose deposition and especially the range of protons in the patient. A promising method discovered only in the last decade is prompt gamma-ray timing (PGT), which relies on the dependence of the detected time-of-flight distribution of prompt gamma radiation on the transit time of protons in the patient. In this study, a Geant4 simulation is developed to predict PGT spectra during irradiation of a PMMA phantom and validated by comparison with experimental data. Both the emission yield of prompt gamma radiation in the phantom and the detection rate are analyzed depending on the proton energy. For comparability with the measured spectra, a multi-step processing of the simulated results is presented. Finally, the simulation is used to demonstrate the sensitivity of the PGT method to changes in range. For this purpose, cavities of different thicknesses and materials can be inserted into the phantom. For appropriately chosen distribution parameters of the simulated PGT spectra, their detected change is compared to the known induced change in range. The sensitivity determined in this way is consistent with previous results for measured spectra within the uncertainties.:1 Einleitung und Motivation 1 2 Theoretische Grundlagen 5 2.1 Wechselwirkung von Protonen mit Materie 5 2.1.1 Bethe-Bloch-Gleichung 6 2.1.2 Reichweite im CSDA-Modell 9 2.1.3 Tiefendosiskurve und Bragg-Peak 10 2.2 Prompt Gamma-Ray Timing 11 2.2.1 Emission prompter Gammastrahlung 11 2.2.2 Korrelation zur Protonen-Reichweite und Dosisdeposition 11 2.2.3 Idee des Prompt Gamma-Ray Timings 14 3 Material und Methoden 17 3.1 Dresdner IBA-Protonentherapie 17 3.1.1 Beschleunigungsprinzip des Isochronzyklotrons 17 3.1.2 Zeitliche Struktur der Protonen-Pakete 18 3.2 Teilchentransportrechnungen mit Geant4 20 3.3 PLD-Format für Pencil-Beam-Scanning-Pläne 21 3.3.1 Geometrische Definition der Spots 21 3.3.2 Dosimetrische Definition der Spots 23 3.3.3 Verwendete Bestrahlungspläne 24 3.4 Messaufbau zur experimentellen Validierung 26 3.4.1 Target – PMMA-Phantom mit verschiedenen Cavitäten 27 3.4.2 Detektoren – CeBr3-Szintillatoren mit Photomultipliern 27 4 Ergebnisse und Diskussion 29 4.1 Simulierte Emission prompter Gammastrahlung 29 4.1.1 Simulierte Emissionsspektren 29 4.1.2 Simulierte Emissionsprofile 30 4.1.3 Totale Emissionsausbeute 31 4.2 Simulierte Detektion prompter Gammastrahlung 33 4.2.1 Detektionsrate und Raumwinkeleffekt 33 4.2.2 Simulierte PGT-Spektren 35 4.2.3 Simulierte Energiespektren 37 4.3 Vergleich simulierter und gemessener Spektren 39 4.3.1 Nachverarbeitung der Simulationsergebnisse 40 4.3.2 Auswahl des Energiefensters 45 4.3.3 Empirisches Modell zur Beschreibung der Zeitspektren 47 4.3.4 Diskussion systematischer Abweichungen 49 4.4 Sensitivität der Simulation gegenüber induzierten Reichweitenänderungen 51 5 Zusammenfassung und Ausblick 59 Anhang 61 A Parameter des Messaufbaus 61 B Angepasste Modellparameter aus Abbildung 4.12 62 C Sensitivität auf Reichweitenänderung bei 162 MeV 63 Literaturverzeichnis 69
333

Advancing Gravitational Wave Astronomy: Novel Methodologies for Data Analysis and Waveform Modelling of Nanohertz and Millihertz Signals

Speri, Lorenzo 18 July 2024 (has links)
Die Erforschung von Gravitationswellen hat unsere Sicht auf das Universum revolutioniert. Mit dem bevorstehenden Start von LISA, einem Weltraum-Gravitationswellendetektor, und neuen Berichten über Hinweise auf einen Gravitationswellenhintergrund im Nanohertz-Bereich aus Pulsar Timing Array (PTA)-Experimenten, eröffnen sich neue Möglichkeiten und Herausforderungen. Diese Dissertation entwickelt innovative Datenanalysetechniken und Wellenformmodelle, um Erkenntnisse aus diesen Beobachtungen zu gewinnen. Ein Schwerpunkt liegt auf der Untersuchung von Extreme Mass Ratio Inspirals (EMRIs) durch LISA. Diese Quellen bestehen aus kleinen, kompakten Objekten, die sich um ein zentrales Schwarzes Loch bewegen. Die Wellenformen von EMRIs bieten die Möglichkeit präziser Parametermessungen, sind jedoch aufgrund ihrer langen Signaldauer und harmonischen Komplexität schwer zu berechnen. Wir präsentieren die Implementierung einsatzbereiter EMRI-Wellenformen im Frequenzbereich für Grafikprozessoren (GPUs) und zentrale Recheneinheiten (CPUs). Zudem untersuchen wir das wissenschaftliche Potenzial von EMRIs innerhalb von Akkretionsscheiben, erforschen den Einfluss von Umwelteffekten mittels bayesianischer Methoden und bewerten die Multimessenger-Aussichten dieser Systeme. Im PTA-Bereich entwickeln wir Methoden zur Optimierung der Datenkombinationen für PTA-Analysen und tragen zum European Pulsar Timing Array bei, indem wir alternative Sampling-Pipelines für die Analyse von Gravitationswellenhintergründen und individuellen Quellen implementieren. Mit transdimensionalen Sampling-Methoden suchen wir nach einzelnen supermassiven Schwarzen Löchern und bewerten deren Signifikanz. Diese Dissertation trägt zur Weiterentwicklung der Gravitationswellenastronomie bei, indem sie neue Methoden und Modelle entwickelt, die tiefere Einblicke in die kosmischen Phänomene ermöglichen, die von LISA- und PTA-Beobachtungen erfasst werden. / Gravitational wave astronomy has reshaped our understanding of the cosmos. As we look towards the future launch of LISA, a space-based gravitational wave detector, and analyze recent evidence of a nanohertz gravitational wave background from Pulsar Timing Array (PTA) experiments, new opportunities and challenges emerge. This thesis delves into developing novel data analysis techniques and waveform models to extract information from these observations. Focusing on LISA, we delve into Extreme Mass Ratio Inspirals (EMRIs). These sources consist of small compact objects spiralling into massive black holes at the centres of galaxies. Their observations are expected to provide precise parameter measurements for these systems. However, EMRI waveform generation poses challenges due to the long signal duration and large harmonic content. For the first time, we provide a fast implementation of EMRI waveforms in the frequency domain, suitable for both graphics processing units (GPUs) and central processing units (CPUs). In addition, we explore the scientific potential of EMRIs embedded in accretion disks. Employing Bayesian inference, we investigate the measurability of environmental effects and explore these systems' multimessenger prospects. Transitioning to PTA, we develop methods to optimize data combinations for PTA analyses. We present our contributions to the second data release of the European Pulsar Timing Array collaboration, which consists of implementing alternative sampling pipelines for gravitational wave background and individual source analyses. Using trans-dimensional sampling methods, we search for individual supermassive black hole binaries and assess their significance. The burgeoning field of gravitational wave astronomy has the potential to transform our understanding of the Universe. The work in this thesis develops new approaches that will facilitate the delivery of the best possible scientific results from current and future gravitational wave observations.
334

Synchronization for Burst-Mode APSK

Shaw, Christopher 10 1900 (has links)
ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / We derive bounds on the performance of data-aided joint estimators for timing offset, carrier phase offset, and carrier frequency offset for use in an APSK packet-based communication link. It is shown that the Cramér-Rao Bound (CRB) is a function of the training sequence, the signal-to-noise ratio (SNR), and the pulse shape. We also compute APSK training sequences of different lengths that minimize the CRB for each of the parameters.
335

Nicolas Roeg : chromatic cartography

Patch, Andrew Mark January 2010 (has links)
The aim of this thesis is to analyse the function of colour in film through three films by British director Nicolas Roeg. To this end, this thesis has the following three correspondent aims: first to consider the theoretical relationship between colour and film within film studies as a discipline. Second, to propose a means of discussing film colour outside the dominant approach of restoration and degradation. Third to explore how Roeg’s implements colour within three of his films Performance, Don’t Look Now, and finally Bad Timing, and the ideological and aesthetic questions that emerge through a consideration of colour in these works. By looking at colour and Nicolas Roeg this thesis will not only present a critical response to the research question but it will also fill a small gap in the current dearth of work that exists on both colour and British cinema in the 1970s.
336

ADVANCES IN WIDEBAND VHS CASSETTE RECORDING

Mason, Terry 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California / In recent years, many designers have turned to digital techniques as a means of improving the fidelity of instrumentation data recorders. However, single and multi-channel recorders based on professional VHS transports are now available which use innovative methods for achieving near-perfect timebase accuracy, inter-channel timing and group delay specifications for long-duration wideband analog recording applications. This paper discusses some of the interesting technical problems involved and demonstrates that VHS cassette recorders are now a convenient and low cost proposition for high precision multi-channel wideband data recording.
337

Morning eating in relation to BMI: energy intake, composition, and timing: NHANES 2005-2010

Virani, Alisha 07 July 2016 (has links)
Background: Obesity continues to be one of the largest public health concerns in our nation. The role of eating patterns as a means for weight management has been studied extensively. However, the role of breakfast in weight management is still poorly understood. The purpose of this study was to understand the role of breakfast in weight management by observing the relationships of energy intake and macronutrient composition, specifically protein and fiber, with weight status during early morning and late morning eating occasions. Methods: Data from two multiple pass 24h dietary recalls from NHANES 2005-2010 were used. N= 4542 non-pregnant, non-lactating participants aged 20-65 y who did not perform shift work and who had a BMI between 18.5 and 60 kg/m2 were included. Individuals with missing data for any of the variables were excluded. Data were analyzed with SPSS software version 21. Each of the 2 days was divided into four time periods: time period 1 defined as the first intake of the day occurring between 12:00 a.m. and 4:59 a.m., time period 2 defined as the first intake occurring between 5:00 a.m. and 8:59 a.m., time period 3 defined as the first intake occurring between 9:00 a.m. and 11:30 a.m., and time period 4 defined as the first intake occurring after 11:30 a.m. Time period 2 was designated as “early morning intake” and time period 3 was designated as “late morning intake”. The other two time periods were designated as energy intake eaten the rest of the day. Energy (kcal), protein (g), and fiber (g) intakes were then calculated for the whole day and for each time period. For early morning and late morning intake, energy, protein and fiber were also divided into 5 categories. Those reporting no intake (0 kcals) made up the first category and quartiles were calculated for those reporting energy intakes of ≥ 0.1 kcal. Modified quartiles for the late morning period using the quartile cutoffs for the early morning time period were also calculated. Similarly, those reporting no intake (0 grams) made up the first category for protein and fiber and quartiles were calculated for those reporting protein or fiber intakes of ≥ 0.01 g. Estimated energy requirements (EER) were determined using the prediction equations developed by the Institute of Medicine (IOM 2005). To determine energy intake reporting plausibility, reported energy intake as a percent of EER was calculated. Standard classifications were used for weight status based on BMI. Descriptive statistics (median and 95% confidence interval) were computed for all variables. Multinomial logistic regression analysis was performed to determine associations between morning energy intake, protein, and fiber categories and risk for overweight (OW) and obesity (OB) for both early morning and late morning time periods. For the energy intake categories, Model 1 was controlled for race/ethnicity, age, gender, poverty-income ratio (PIR), smoking status, alcohol consumption, physical activity, self-reported chronic disease, daily eating frequency, and the two day morning eating pattern. Model 2 was controlled for all of the covariates in Model 1 plus energy intake before and after morning eating. Model 3 was controlled for all of the covariates in Model 2 plus energy intake reporting plausibility. For the protein and fiber categories, Model 1, 2, and 3 controlled for the same covariates as the energy intake categories and also controlled for reported energy intake during the early or late morning eating occasions. A p-value of <0.05 was considered statistically significant. Results: For the energy intake categories during the early morning, compared to no morning intake, Model 1 showed a lower risk for OB in Q2, but no other relationships were seen in any of the other quartiles. Similar results were seen in Model 2 where a lower risk for OB in Q2 was present. In Model 3, however, (controlled for energy intake reporting plausibility) the relationship between energy intake in Q2 and a lower risk for OB disappeared and a higher risk for OW and OB became apparent in Q4. For the late morning analysis, Models 1 and 2 were similar in that there was no association between morning energy intake category and weight status, but for Model 3 there was a higher risk for OW and OB in Q2-Q4. When we used the modified late morning quartile cutoffs in the analysis to eliminate potential bias due to the different quartile cutoffs for the early and late morning eating occasions, the higher risk for OW and OB was still present in Q2-Q4 and the ORs were attenuated compared to when the original late morning cutoffs were used. In terms of composition, compared to no morning intake, there were no significant associations seen between early or late morning protein consumption and weight status in any of the models. Additionally, for the early morning analysis of fiber, Models 1 and 2 did not show an association between morning fiber intake category and weight status, but for Model 3 there was a lower risk for OB in Q4. For the late morning analysis, Model 1 showed a higher risk for OW in Q2, but no other relationships were seen in any of the other quartiles. Similar results were seen in Model 2 where a higher risk for OB in Q2 was present. In Model 3, however, this relationship disappeared and no other associations were seen in any of the other quartiles. Conclusion: In comparison to having no morning intake (i.e., “skipping”) there was an elevated risk for OW and OB when consuming higher amounts of energy during the early morning and moderate to high amounts of energy during the late morning. The risk for OW and OB was higher in the late morning compared to the early morning eating occasions, in part, but not entirely, because of the higher amounts of energy consumed during the later morning in comparison to the early morning. Therefore, higher energy in both early morning and late morning increase the risk for OW and OB. Furthermore, later timing may increase the risk for OW and OB, independent of energy intake the rest of the day, since individuals who ate later also had higher energy intakes in the later morning compared to the early morning. In addition, compared to no morning intake of fiber, having a very high fiber intake in the early morning, but not the late morning, may decrease the risk for OB independent of energy intake and fiber intake the rest of the day. These associations may not be apparent unless energy intake reporting plausibility is taken into account.
338

On the developmental significance of female pubertal timing

Skoog, Therése January 2008 (has links)
Puberty is the process of becoming sexually mature and it has fundamental somatic and psychosocial implications. The focus of this dissertation was the short and long term developmental significance, concerning both soma et psyche, of female pubertal timing. Four studies were designed to accomplish these aims. Six samples of different ages from different countries and from different time points, comprising several thousand females some of which were followed longitudinally, were used. Age at menarche was used as the primary measure of pubertal maturation. The first main aim of this dissertation was to explore the mechanisms that might explain the well-established link between female pubertal timing and problem behavior, and to identify contextual conditions at which associations are stronger or weaker. Existing explanations are unsatisfactory and little is known about conditions that might affect the strength of the associations. In Paper I, we tested and confirmed a peer socialization hypothesis as a satisfactory explanation for the link between early puberty and problematic adjustment. In short, this hypothesis posits that early developing girls associate with older peers and boyfriends because they feel more mature than their same age peers, and through these peers and boyfriends the early developed girls are channeled into more socially advanced behaviors, including normbreaking. This should be particularly true in contexts where heterosexual relationships are sanctioned and where there is an abundance of deviant youth. In Paper II, I used a biopsychosocial approach and studied pubertal timing along with self-perceptions of maturity and early romantic relationships. The findings revealed that early puberty had very different implications depending on the psychological and social contexts in which it was embedded. For instance, when early puberty was coupled with feeling mature and having early romantic relationships, it was associated with adjustment problems. When early puberty was coupled with neither, it was not linked to particularly high levels of problem behavior. In stark contrast to the vast literature on the role of female pubertal timing in adolescence, the literature on long-term implications is remarkably limited. For this reason, the second main aim of this dissertation was to study the adult implications of female pubertal timing. In Papers III and IV, we examined long term implications of pubertal timing, particularly as it relates to somatic development. The findings suggested that pubertal timing does have future implications for women’s body perception and composition, with early developing females having higher body mass indexes in adulthood, but only under certain circumstances. The findings of this dissertation help further understanding of the soma et psyche implications of female pubertal timing. They indicate that pubertal timing has concurrent and future implications. It seems, however, that timing is not everything. The developmental significance of female pubertal timing appears to be very different under different contextual conditions. Thus, it is only when girls’ psychological and social contexts are considered that fruitful predictions can be made. As such, the findings have important implications for prevention, policy, and practice.
339

Timing the Start of Material Substitution Projects: Creating Switching Options under Volatile Material Prices

Fisch, Jan Hendrik, Ross, Jan-Michael 05 1900 (has links) (PDF)
Firms developing new products often face the challenge of making investment decisions under uncertain input-cost conditions due to the price volatilities of the materials they use. These decisions need to be made long before the final products are launched on the market. Therefore, firms who invest in the opportunity to switch materials in a timely manner will have the flexibility to react to material price changes and realize competitive advantages. However, volatile material prices may also cause a firm to delay investment. Using real-options reasoning, this article studies the influence of input-cost fluctuations on the timing decision to start new product development (NPD) and thus create the follow-on opportunity to later replace an existing product. A model that combines waiting and switching options to derive influencing factors of the flexibility value which triggers the investment is developed and tested on a sample of material substitution projects from manufacturing firms. The results show how price uncertainty of the new and the old material, their joint price development, the expected project duration, and competitive preemption are related to the propensity to delay the start of NPD. The findings provide new insights on how timing in adopting materials can be used to hedge exposure to volatile material prices. The insights are relevant for adopters and producers of new materials, as well as for policy makers who strive for supporting the diffusion of new materials. (authors' abstract)
340

The Life History Narrative: How Early Events and Psychological Processes Relate to Biodemographic Measures of Life History

Black, Candace Jasmine January 2016 (has links)
The aim of this project is to examine the relationships between two approaches to the measurement of life history strategies. The traditional method, termed here the biodemographic approach, measures developmental characteristics like birthweight, gestation length, inter-birth intervals, pubertal timing, and sexual debut. The alternative method under exploration, termed here the psychological approach, measures a suite of cognitive and behavioral traits such as altruism, sociosexual orientation, personality, mutualism, familial relationships, and religiosity. Although both approaches are supported by a large body of literature, they remain relatively segregated. This study draws inspiration from both views, integrating measures that assess developmental milestones, including birthweight, prematurity, pubertal timing, and onset of sexual behavior, as well as psychological life history measures such as the Mini-K and a personality inventory. Drawing on previous theoretical work on the fundamental dimensions of environmental risk, these measures are tested in conjunction with several scales assessing the stability of early environmental conditions, including both "event-based" measures that are defined with an external referent, and measures of internal schemata, or the predicted psychological sequelae of early events. The data are tested in a three-part sequence, beginning with the measurement models under investigation, proceeding to an exploratory analysis of the causal network, and finishing with a cross-validation of the structural model on a new sample. The findings point to exciting new directions for future researchers who seek to integrate the two perspectives.

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