Long calls are highly stereotyped calls used by primates to communicate across distances; the function of these calls has been debated. Goustard (1983:405) defines them as " ... an extended utterance which has a high degree of structural organization." Habitat structure has been considered a shaping force of the acoustic structure of nonhuman primate long calls as part of the local adaptation hypothesis (Brown et al. 1995). This study examines the effect of phylogeny, habitat density, diet, and social and mating systems as seen through the structure of the fundamental frequency (the lowest frequency of the call; Rogers 2000; Ey, Pfefferle, and Fischer 2007). Results of ANOVA and post hoc tests indicate there are both phylogenetic and habitat-related influences in the acoustic structure of the first phrase (first part of the long call separated from the next by a discrete break). Dietary preferences and social and mating systems are also correlated with acoustic structure.

Over the past century, suburban living has been a sign of prosperity and a manifestation of the American dream. Owning a large single-family home, a spacious yard and a car have become a measure of success. The trend towards suburban habitation has created a surge of sprawled development that has led to an inefficient built-environment The attitudes, and lifestyles of the current young population are no longer the same; millennials are getting married and starting families later, with a greater demand to settle in urban areas. They are placing higher value towards living near jobs and walkable amenities and are choosing to wait longer on purchasing a home. The increased demand for urban living has caused city rents to skyrocket. The percentage of individuals who live in urban areas is expected to increase by 20% in the next 35 years. The overpopulation of cities has caused a surge in housing costs - making urban settlement increasingly unaffordable. The suburbs fail to provide millennials and young profession s with an adequate supply of rental housing due to its dominate presence of single family homes. The expensive cost of cities, along with the lack of viable housing in the suburbs has many young professionals stuck, in search of a feasible place to live. The suburbs have potential to be urbanized, and to provide a mix of housing types that accommodates a more diverse set of residents, however, there is a slew of pre-development hurdles that halt the process of high-density housing construction. This is especially seen in Long Island, NY, where residents are hesitant to allow the production of multi-family projects in their backyard. Transit Oriented development can serve as a solution to this problem, by stimulating the growth of long island towns, minimizing traffic impact, and catering specifically to millennials and seniors. This would allow the built environment of areas outside of transit hubs to preserve their single-family character, and would have little effect on the existing structure of school districts. / 0 / SPK / specialcollections@tulane.edu

New graduate nurses often lack clinical skill competency. In a single year, a long-term care facility located in the midwestern region of the United States reported 25 clinical errors, each costing the facility approximately $10,000. Root-cause analysis revealed 85% of those errors were made by nurses in their 1st year of practice. The increase in clinical errors were attributed to insufficient clinical preparation prior to independent practice. A review of the current scholarly literature suggested simulation had demonstrated efficacy in the development and maintenance of clinical nursing skills and answered the practice-focused question: Development of a skills simulation program for incorporation into nursing orientation will likely increase skill competency among new graduate nurses. Benner's novice to expert theory and the John Hopkins nursing evidence-based practice model were used to develop and evaluate an evidence-based curriculum for a clinical skills simulation program. Using a validated tool, the proposed curriculum was evaluated by a panel of five subject matter experts. Synthesis and analysis of that evaluation suggested implementation of the proposed curriculum would increase basic nursing skill competency; therefore, the recommendation was made to incorporate the program into new hire nursing orientation. The curriculum can be used to develop or maintain general or specialty-specific clinical skill sets and implemented in most any type facility requiring the use of clinical nursing skills. Clinical skill competency reduces the number of clinical errors, decreases patient morbidity and mortality, increases the quality of care, and reduces the overall cost of care, thereby promoting positive social change.

The current research was undertaken to determine the long run performance of Initial Public Offerings (IPOs) listed on the Johannesburg Stock Exchange (JSE) in South Africa. The three year abnormal returns were assessed for IPOs listed between 1995 and 2006 comprising a sample of 229. Using the Buy and Hold Abnormal Return (BHAR) and Cumulative Abnormal Return (CAR) methods, it was found that the IPOs underperformed the market by 50% and 47% for BHAR and CAR respectively. The JSE All Share Index was used as a benchmark. The research also investigated the effect of firm size on IPO performance. The relationship between IPO activity and performance was analysed as well as the performance of IPOs from different sectors. Gross proceeds of the offers were used as a proxy for firm size and it was shown that by splitting the sample into different size groups, there were significant differences between the returns from these groups. There was no relationship found between IPO activity and performance using a linear regression. Using an Analysis of Variance (ANOVA) it was determined that there were significant differences between the performance of IPOs in the different sectors of technology, industrials, financials and mining. Copyright / Dissertation (MBA)--University of Pretoria, 2010. / Gordon Institute of Business Science (GIBS) / unrestricted

This study provides a comprehensive modeling evaluation of the dynamic stability of Long Combination Vehicles (LCVs) that are commonly operated on U.S. highways, using multibody dynamic simulations in MATLAB/Simulink®. The dynamic equations for a tractor with two trailers connected by an A-frame converter dolly (A-Dolly) are developed. The dynamic model is used for running MATLAB® simulations, with parameters that are obtained through measurements or obtained from other sources. The simulation results are verified using track test data to establish a baseline model. The baseline model is used for parametric studies to evaluate the effect of trailer cargo weight, center of gravity (CG) longitudinal location, and trailer wheelbase. The dynamic model is further used to analyze both single-trailer and double-trailer trucks through nondimensionalization. The nondimensionalization method has the added advantage of enabling studies that can more broadly apply to various truck configurations. The simulation results indicate that increasing the trailer wheelbase reduces rearward amplification due to the damping effect of the longer wheelbase. A larger momentum ratio due to increased trailer gross weight increases rearward amplification. The detailed models of pneumatic disc and drum brakes in LCVs, including the airflow delay and thermal characteristics, are also developed and are coupled with the articulated vehicle dynamic models. The disc and drum brake braking performance are evaluated and compared in straight-line braking and combined steering and braking at a 150-ft J-turn maneuver. In straight-line braking, the simulation results indicate that disc brakes provide significantly shorter braking distance than drum brakes at highway speeds on a dry road, mainly due to their larger braking torque. On a slippery road surface, however, the greater braking torque causes more frequent wheel lockup and ABS activation at higher speeds, and disc brakes do not provide a substantially shorter braking distance than drum brakes. The simulations also point out that the disc brakes' cooling capacity is higher than the drum brake, with the cooling efficiency heavily dependent on the airflow speed. At higher driving speeds, the airflow accelerates to a turbulent flow and increases the convection efficiency. For braking in-turn maneuvers, at higher entering speeds, disc brakes decelerate the vehicle slightly sooner and then scrub speed faster, resulting in better roll stability when compared with drum brakes. / Doctor of Philosophy / Long combination vehicles (LCVs) are the combination of a tractor and two or more trailers and have been widely used on U.S. highways for cargo transport. Although LCVs have a larger cargo volume and provide more modularity in transporting goods, at higher speeds, they can be more prone to rollovers and require longer stopping distances and space to maneuver from one lane of travel to another. This study investigates the dynamic stability of an LCV, A-double trailer that includes a tractor, two trailers, and a dolly through modeling and simulation. The dynamic equations of each vehicle unit are derived based on Newtonian Mechanics (i.e., F = ma). The dynamic models are tuned to match the track testing results for similar vehicles, performed by the Center for Vehicle Systems and Safety (CVeSS) at Virginia Tech in the past. A novel evaluation method that nondimensionalizes the equations is used to allow for ease of use for LCVs with different cargo weights, lengths, and other similar variations. The dimensionless parameters are the function of vehicle parameters and express the relationship among the magnitude of vehicle parameters. Using the nondimensionalized model, the study performs a frequency analysis of the effect of trailer cargo weight, CG longitudinal position, and trailer wheelbase on roll stability and rearward amplification. Rearward amplification is the ratio of peak lateral acceleration between the tractor and the rearmost trailer. Slow-sweeping sinusoidal steering from 0.01 Hz to 0.6 Hz is used for the simulation analysis. The simulation results show that by increasing the trailer wheelbase—the distance from the trailer kingpin to the axle—the vehicle is more laterally stable because the longer wheelbases make the trailer more resistive to spinning around. Additionally, the pneumatic disc and drum brake models and thermal models are developed and coupled with the vehicle dynamic model. The disc and drum brake braking performance are investigated during both straight-line braking and combined steering and braking in a curve. The disc brakes generate a greater brake torque compared with drum brakes, and as such can decelerate the vehicle more efficiently on dry road surfaces, particularly at higher speeds such as highway speeds. This improves avoidance during emergency stops and roll stability during traveling in a curve, such as at a highway exit. The disc brakes also have greater cooling capacity because they can transfer the generated heat to the air due to the greater airflow and turbulence caused naturally by their design. This greatly helps to keep the brakes cooler on the track and to improve their stopping efficiency.

This study addressed the relational maintenance strategies and the meaning 23 to 35 year old students attributed to their long-distance dating relationships. Ten participants completed in depth interviews exploring the thoughts and feelings individuals held about their current long-distance partner and relationship. Also, commitment and quality of alternatives were addressed including the strengths and weaknesses of the respondent's relationship. Common themes of strong friendship, absolute trust, commitment to one partner, and using the technique of reminiscing were all dominant issues that emerged from the interview data. Social network approval as well as positive role models in the form of older siblings was also instrumental in lending support to the success and general positive attitude felt by participants about the geographic separation. Methods of communication included the telephone and e-mail, which was substituted or supplementary when high phone bills created financial concerns for the respondents. Variation in physical visitation was due to the intersection of academic schedule, affordable transportation, attitude towards work disruptions, geographic distance, and a general willingness to travel. Participants told a story of the geographic separation as both a temporary and necessary inconvenience, rather than a major obstacle or focal point of the relationship. Future directions for studying long-distance dating relationships include collecting couple data and examining gender differences to determine if sex has an impact on how geographic separation is viewed. / Master of Science

Yes / This study investigates whether, how and why industry performance can drive long-term return reversals. Using data from the UK, we find that firms in losing industries significantly outperform those in winning industries over the subsequent five years. These industry reversals remain strong and persistent after controlling for stock momentum, industry momentum, seasonal effects and traditional risk factors. We find a strong influence of past industry performance on stock return reversals. Our results also show that past industry performance is the driving force behind long-term reversals. Specifically, we find that industry components drive stock reversals, while past stock performance does not explain industry reversals. Further analysis suggests that industry reversals are present in both good and bad states of the economy and are stronger in industries with high valuation uncertainty. This implies that industry reversals are more likely to be a result of mispricing.

This study examines the performance of long-short equity trading strategies from January 1990 to December 2010. This study combines two financial screens that will yield candidates for both long and short positions for each month during the aforementioned time period. Two long-short strategies are tested: (1) perfectly-hedged, or equal allocation to long and short positions, and (2) net-long. The results of this thesis reveal that if a long-short equity manager is able to successfully determine what companies are overvalued and undervalued and actively rebalance their portfolio, perfectly-hedged and net-long strategies can generate superior risk-adjusted alpha.

La mémoire longue, aussi appelée la dépendance à long terme (LRD), est couramment détectée dans l’analyse de séries chronologiques dans de nombreux domaines, par exemple,en finance, en économétrie, en hydrologie, etc. Donc l’étude des séries temporelles à mémoire longue est d’une grande valeur. L’introduction du processus ARFIMA (fractionally autoregressive integrated moving average) établit une relation entre l’intégration fractionnaire et la mémoire longue, et ce modèle a trouvé son pouvoir de prévision à long terme, d’où il est devenu l’un des modèles à mémoire longue plus populaires dans la littérature statistique. Précisément, un processus à longue mémoire ARFIMA (p, d, q) est défini comme suit : Φ(B)(I − B)d (Xt − µ) = Θ(B)εt, t ∈ Z, où Φ(z) = 1 − ϕ1z − · · · − ϕpzp et Θ(z) = 1 + · · · + θ1zθpzq sont des polynômes d’ordre p et q, respectivement, avec des racines en dehors du cercle unité; εt est un bruit blanc Gaussien avec une variance constante σ2ε. Lorsque d ∈ (−1/2,1/2), {Xt} est stationnaire et inversible. Cependant, l’hypothèse a priori de la stationnarité des données réelles n’est pas raisonnable. Par conséquent, de nombreux auteurs ont fait leurs efforts pour proposer des estimateurs applicables au cas non-stationnaire. Ensuite, quelques questions se lèvent : quel estimateurs doit être choisi pour applications, et à quoi on doit faire attention lors de l’utilisation de ces estimateurs. Donc à l’aide de la simulation de Monte Carlo à échantillon fini, nous effectuons une comparaison complète des estimateurs semi-paramétriques, y compris les estimateurs de Fourier et les estimateurs d’ondelettes, dans le cadre des séries non-stationnaires. À la suite de cette étude comparative, nous avons que (i) sans bonnes échelles taillées, les estimateurs d’ondelettes sont fortement biaisés et ils ont généralement une performance inférieure à ceux de Fourier; (ii) tous les estimateurs étudiés sont robustes à la présence d’une tendance linéaire en temps dans le niveau de {Xt} et des effets GARCH dans la variance de {Xt}; (iii) dans une situation où le probabilité de transition est bas, la consistance des estimateurs quand même tient aux changements de régime dans le niveau de {Xt}, mais les changements ont une contamination au résultat d’estimation; encore, l’estimateur d’ondelettes de log-regression fonctionne mal dans ce cas; et (iv) en général, l’estimateur complètement étendu de Whittle avec un polynôme locale (fully-extended local polynomial Whittle Fourier estimator) est préféré pour une utilisation pratique, et cet estimateur nécessite une bande (i.e. un nombre de fréquences utilisés dans l’estimation) plus grande que les autres estimateurs de Fourier considérés dans ces travaux. / Long memory, also called long range dependence (LRD), is commonly detected in the analysis of real-life time series data in many areas; for example, in finance, in econometrics, in hydrology, etc. Therefore the study of long-memory time series is of great value. The introduction of ARFIMA (fractionally autoregressive integrated moving average) process established a relationship between the fractional integration and long memory, and this model has found its power in long-term forecasting, hence it has become one of the most popular long-memory models in the statistical literature. Specifically, an ARFIMA(p,d,q) process X, is defined as follows: cD(B)(I - B)d X, = 8(B)c, , where cD(z)=l-~lz-•••-~pzP and 8(z)=1-B1z- .. •-Bqzq are polynomials of order $p$ and $q$, respectively, with roots outside the unit circle; and c, is Gaussian white noise with a constant variance a2 . When c" X, is stationary and invertible. However, the a priori assumption on stationarity of real-life data is not reasonable. Therefore many statisticians have made their efforts to propose estimators applicable to the non-stationary case. Then questions arise that which estimator should be chosen for applications; and what we should pay attention to when using these estimators. Therefore we make a comprehensive finite sample comparison of semi-parametric Fourier and wavelet estimators under the non-stationary ARFIMA setting. ln light of this comparison study, we have that (i) without proper scale trimming the wavelet estimators are heavily biased and the y generally have an inferior performance to the Fourier ones; (ii) ail the estimators under investigation are robust to the presence of a linear time trend in levels of XI and the GARCH effects in variance of XI; (iii) the consistency of the estimators still holds in the presence of regime switches in levels of XI , however, it tangibly contaminates the estimation results. Moreover, the log-regression wavelet estimator works badly in this situation with small and medium sample sizes; and (iv) fully-extended local polynomial Whittle Fourier (fextLPWF) estimator is preferred for a practical utilization, and the fextLPWF estimator requires a wider bandwidth than the other Fourier estimators.

The geographic isolation of populations can result in a metapopulation effect where regional dynamics of extinction and colonization are more important to population viability than local dynamics of individuals' birth or death. When this partial isolation is maintained for many generations genetic variability can be geographically structured. Populations of temperate-zone anuran amphibians are often considered to be geographically isolated on relatively small spatial scales due to the animals presumed high site fidelity and strict dependence on moisture for respiration and breeding. As a result, temperate, pond-breeding anuran amphibian populations are considered likely candidates to test hypotheses of metapopulation theory, movement and phylogeography. Using data from the Fowler's toad, (Bufo fowleri) I test the applicability of metapopulation theory, the likelihood of limited movement and the strength of phylogeographic structure. Specifically, I show that the generalization of the amphibians-as-metapopulations paradigm, due to their limited dispersal capabilities, is not supported (I). Bufo fowleri movement is well described by an inverse power function. Whereas most individuals do not move, some move long distances. There is no sex bias to this movement and I propose the hypothesis that the animals moving the longest distances are aided by the passive action of lake currents (II). B. fowleri juveniles are not a dispersal stage. They move neither farther nor faster than adults. The observation of predominantly juvenile contribution to a dispersal pool is due to their abundance---there are simply many more juveniles than adults (III). My observations of amphibian population turnover do not support the predictions of two specific metapopulation models when parameterized on a local (<10km) or regional scale (~300km) (IV). B. fowleri populations in Canada exhibit both shallow and deep phylogeographic structure. The shallow divisions are geo