Study of non-linear optimization techniques

Nonlinear optimization techniques in dynamic programming and solution of ordinary nonlinear differential equations by Runge-Kutta metho

Implicit memory and cognitive aging

It is well documented that explicit (declarative, conscious) memory declines in normal aging. Studies have shown a progressive reduction in this form of memory with age, and healthy older adults (typically aged 65+ years) usually perform worse than younger adults (typically aged 18-30 years) on laboratory tests of explicit memory such as recall and recognition. In contrast, it is less clear whether implicit (procedural, unconscious) memory declines or remains stable in normal aging. Implicit memory is evident when previous experiences affect (e.g., facilitate) performance on tasks that do not require conscious recollection of those experiences. This can manifest in rehearsed motor skills, such as playing a musical instrument, but is typically indexed in the laboratory by the greater ease with which previously studied information is processed relative to non-studied information (e.g., repetition priming). While a vast amount of research has accumulated to suggest that implicit memory remains relatively stable over the adult lifespan, and is similar in samples of young and older adults, other studies have in contrast revealed that implicit memory is subject to age-related decline. Improving methods for determining whether implicit memory declines or remains stable with age is an important goal for future research, as the issue not only has significant implications for an aging society regarding interventions likely to ameliorate the effects of age-related explicit memory decline, but can also inform our theoretical understanding of human memory systems

Noise measurements for a twin-engine commercial jet aircraft during 3 deg approaches and level flyovers

Noise measurements have been made with a twin-engine commercial jet aircraft making 3 deg approaches and level flyovers. The flight-test data showed that, in the standard 3 deg approach configuration with 40 deg flaps, effective perceived noise level (EPNL) had a value of 109.5 effective perceived noise decibels (EPNdB). This result was in agreement with unpublished data obtained with the same type of aircraft during noise certification tests; the 3 deg approaches made with 30 deg flaps and slightly reduced thrust reduced the EPNL value by 1 EPNdB. Extended center-line noise determined during the 3 deg approaches with 40 deg flaps showed that the maximum reference A-weighted sound pressure level (LA,max)ref varied from 100.0 A-weighted decibels 2.01 km (108 n. mi.) from the threshold to 87.4 db(A) at 6.12 km (3.30 n. mi.) from the threshold. These test values were about 3 db(A) higher than estimates used for comparison. The test data along the extended center line during approaches with 30 deg flaps were 1 db(A) lower than those for approaches with 40 deg flaps. Flight-test data correlating (LA,max)ref with thrust at altitudes of 122 m (400 ft) and 610 m (2000 ft) were in agreement with reference data used for comparison

Numerical integration of second order differential equations

Performance characteristics of higher order approximations of Runge-Kutta type are analyzed, and performance predictors for time required on machine and for error size are developed. Technique is useful in evaluating system performance, analyzing material characteristics, and designing inertial guidance and nuclear instrumentation and materials

Does the Environmental Orientation of Local Officials Affect Local Environmental Policy?

People often discuss the need to educate local officials about the environment, but little research has been done to support that need. The need to educate this group is based primarily on anecdotal evidence—green partnerships getting underway in Louisville and Lexington and similar efforts in other municipalities that are supported by local officials. Some believe that if you educate local officials about the environment they will become environmentally responsible citizens who promote and support more progressive environmental policies. Several models exist that describe environmental responsibility. In its most basic form environmental responsibility is a function of knowledge, attitudes and behavior. However, values and interests also shape environmental attitudes. Environmentally responsible behavior has been shown to be a function of environmental values, personality traits, gender, psychological variables and the situational context. Local Agenda 21 (LA 21), which was adopted at the United Nations Conference on Environment and Development (UNCED) held in Rio de Janerio, Brazil in 1992, outlines a planning process that provides an opportunity for local governments to work within their communities to adopt sustainable practices. Since then, local sustainability efforts in the U.S. have taken many forms including curbside recycling, brownfield redevelopment, mass transit and the formation of citizen advisory councils. Researchers have found communities that adopt sustainability programs are older and less reliant on manufacturing. They are often a host to a major university and tend to have higher levels of education attainment. Kentucky communities are not among the small list of U.S. communities that have adopted LA 21 strategies. However, environmental progress is happening in Kentucky’s communities. The purpose of this research is to better understand the relationship between environmental responsibility of local officials and local environmental policies. Two questions are answered with this research: Are local officials environmentally responsible citizens? Do environmentally responsible local officials produce environmentally progressive policies? In this study environmental responsibility is measured by environmental knowledge, attitudes and behavior. A survey was administered to the county judge executives in Kentucky and the two mayors of merged governments to collect data on this. The data collected were analyzed with respect to: respondents individual characteristics such as age and income; and responses from the same survey administered to a sample of Kentuckians in 2004; and solid waste management data, which serve as indicators of environmental progress, from the respondents corresponding counties. The findings of this research are mixed. Attitudes do not appear to be a function of environmental knowledge. Behavior, though, was linked to environmental knowledge and attitudes but only in bivariate analysis. The group surveyed is fairly knowledgeable about the environment. They answered more questions correctly than a sample of Kentuckians surveyed in 2004. They were similarly concerned about the environment as the Kentucky sample, but did report more environmentally responsible behavior. Based on this analysis, environmental knowledge is a function of the respondents’ education attainment level. An increase in education increased environmental knowledge. Attitude is a function of political affiliation. Democrats expressed more concern and support for the environment than republicans. Finally, reported environmentally responsible behavior (ERB) is a function of the respondents’ age, number in household and years of service. All of which positively correlated to ERB. Five indicators of environmental progress were used but only two—presence of curbside recycling and employment of a full-time solid waste coordinator—correlate to local officials’ environmental knowledge in multivariate analysis. Knowledge is inversely correlated to curbside recycling and is positively correlated to the employment of a full-time solid waste coordinator. Other variables including population density and county median household income positively correlated to these variables. To better understand the relationship between environmental responsibility of local officials and local environmental policies, more research is needed. A larger sample including other county and city local officials should be surveyed. More research should be done to better understand the correlation between factors related to urbanization and local environmental policies. Based on the literature review, local officials need to be aware of their role in the sustainability effort in the U.S. Local governments, given that they are closest to the people and environmental problems, play a pivotal role. While other factors such as special interest groups and environmental problems may be demanding stronger environmental policies, local officials will be a part of proposing and adopting those policies

Relationships Between Shame, Cognitive Distortions and Positive Relationships with Others Among Young Adults, and Changes in Shame Resulting from an Intervention Focusing on Cognitive Distortions

Experiences of shame are strongly correlated with diminished social relations in individuals of all ages. Difficult and traumatic early childhood situations and experiences such as partner abuse, sexual violence in situations with differences in status commonly lead to shame. Difficult family situations and traumatic situations also frequently result in cognitive distortions, flawed thinking which often continues through adulthood. This study evaluated the experiences of shame, satisfaction of social relations, and cognitive distortions of young adults ages 18-25 years of age. Participants included 88 young adults recruited from social media sites and email contacts. Self-report measures were used to evaluate the level of these factors in participants, including before- and after-measurements to determine results on changes in levels of shame and cognitive distortions from a psychoeducational intervention on learning about cognitive distortions. Pearson’s r tests were carried out to determine the relationships between the variables, with paired t-tests carried out to determine the effect of the psychoeducational intervention on levels of shame and on cognitive distortions. Results of these tests showed a strong positive relationship between shame and cognitive distortions in young adults and a negative relationship between cognitive distortions and relationships, with no relationship found between levels of shame and relationships. The paired t-tests found significant changes in both cognitive distortions and levels of shame, following a brief intervention focused on learning about cognitive distortions. The value of this study will include the way in which learning about cognitive distortions can reduce shame in individuals and perhaps result in improved relationships in young adults

Sum of Two Squares - Pair Correlation and Distribution in Short Intervals

In this work we show that based on a conjecture for the pair correlation of integers representable as sums of two squares, which was first suggested by Connors and Keating and reformulated here, the second moment of the distribution of the number of representable integers in short intervals is consistent with a Poissonian distribution, where "short" means of length comparable to the mean spacing between sums of two squares. In addition we present a method for producing such conjectures through calculations in prime power residue rings and describe how these conjectures, as well as the above stated result, may by generalized to other binary quadratic forms. While producing these pair correlation conjectures we arrive at a surprising result regarding Mertens' formula for primes in arithmetic progressions, and in order to test the validity of the conjectures, we present numericalz computations which support our approach.Comment: 3 figure

An effect of age on implicit memory that is not due to explicit contamination: implications for single and multiple-systems theories

Recognition memory is typically weaker in healthy older relative to young adults, while performance on implicit tests (e.g., repetition priming) is often comparable between groups. Such observations are commonly taken as evidence for independent explicit and implicit memory systems. On a picture version of the continuous identification with recognition (CID-R) task, we found a reliable age-related reduction in recognition memory, while the age effect on priming did not reach statistical significance (Experiment 1). This pattern was consistent with the predictions of a formal single-system model. Experiment 2 replicated these observations using separate priming (continuous identification; CID) and recognition phases, while a combined data analysis revealed a significant effect of age on priming. In Experiment 3, we provide evidence that priming in this task is unaffected by explicit processing, and we conclude that the age difference in priming is unlikely to have been driven by differences in explicit processing between groups of young and older adults (“explicit contamination”). The results support the view that explicit and implicit expressions of memory are driven by a single underlying memory system