Uncertainty in marine weather routing

Weather routing methods are essential for planning routes for commercial shipping and recreational craft. This paper provides a methodology for quantifying the significance of numerical error and performance model uncertainty on the predictions returned from a weather routing algorithm. The numerical error of the routing algorithm is estimated by solving the optimum path over different discretizations of the environment. The uncertainty associated with the performance model is linearly varied in order to quantify its significance. The methodology is applied to a sailing craft routing problem: the prediction of the voyaging time for an ethnographic voyaging canoe across long distance voyages in Polynesia. We find that the average numerical error is $0.396\%$, corresponding to $1.05$ hours for an average voyage length of $266.40$ hours. An uncertainty level of $2.5 \%$ in the performance model is seen to correspond to a standard deviation of $\pm 2.41-3.08\%$ of the voyaging time. These results illustrate the significance of considering the influence of numerical error and performance uncertainty when performing a weather routing study

Mind the gap(s)…in theory, method and data: Re-examining Kanazawa (2006)

Kanazawa (2006) has put forward an evolutionarily grounded theory which claims that ‘individuals in wealthier and more egalitarian societies live longer and stay healthier not because they are wealthier or more egalitarian but because they are more intelligent’ (2006: 637). The claim rests on an argument which asserts that general intelligence is a solution to evolutionarily novel problems and that most dangers to health in contemporary society are evolutionarily novel. Kanazawa also claims that this relationship does not hold in sub-Saharan Africa. These claims are based on a cross-national analysis which finds a positive correlation between ‘national’ IQ scores and mortality data. The implication is that intelligence is the principal factor determining longevity in the rest of the world, regardless of issues such as adequacy of diet and availability of health care. Kanazawa’s theoretical claims about the evolution of general intelligence as a domain-specific adaptation are inconsistent with adaptationist analysis: natural selection does not solve general problems. The assumptions that sub-Saharan Africa is more representative of the evolutionary past than is the rest of the world, and that most hazards to health in contemporary society are evolutionarily novel, are implausible. The methods used are inadequate because Kanazawa argues for causation from correlation and fails to consider alternative explanations. The IQ data are flawed for reasons to do with sample size and sampling, extrapolation, and inconsistency across measures. Nor are they temporally compatible with the economic and demographic data

GEMSToolbox: A novel modelling tool for rapid screening of mines for geothermal heat extraction

Mine water geothermal heat extraction is a promising technology to provide long-term, zero carbon heating in former coal mining regions. However to allow the technology to develop further, modelling tools which are faster than 3D coupled-process simulators and more site specific than analytical solutions need to be developed. A novel modelling tool, GEMSToolbox, was designed for assessing the feasibility of disused and flooded mine workings for such geothermal heat extraction. The basis of GEMSToolbox is built upon tested, computationally efficient modelling methods, and combines efficient solvers for water flow through the mine workings with fast solution methods for heat exchange between the water in the mine galleries and the surrounding rock mass. It expands and improves on these methods by (1) allowing for arbitrarily complex multi-seam mine geometries, and (2) addressing potential thermal interaction between nearby mine galleries using a novel geometric weighting technique. Fast calculation allows for wide parameter investigation studies that is required given the often uncertain state of disused mine systems. This makes the tool ideally suitable for the feasibility stage of a project for which site-specific yet computationally efficient alternative tools are currently lacking. The tool is demonstrated on a case study using plans from a real mine system and shows how it can be used to evaluate the long-term thermal performance of a mine water geothermal heat scheme

Polydispersity and ordered phases in solutions of rodlike macromolecules

We apply density functional theory to study the influence of polydispersity on the stability of columnar, smectic and solid ordering in the solutions of rodlike macromolecules. For sufficiently large length polydispersity (standard deviation $\sigma>0.25$) a direct first-order nematic-columnar transition is found, while for smaller $\sigma$ there is a continuous nematic-smectic and first-order smectic-columnar transition. For increasing polydispersity the columnar structure is stabilized with respect to solid perturbations. The length distribution of macromolecules changes neither at the nematic-smectic nor at the nematic-columnar transition, but it does change at the smectic-columnar phase transition. We also study the phase behaviour of binary mixtures, in which the nematic-smectic transition is again found to be continuous. Demixing according to rod length in the smectic phase is always preempted by transitions to solid or columnar ordering.Comment: 13 pages (TeX), 2 Postscript figures uuencode

Intergenerational conflicts may help explain parental absence effects on reproductive timing: a model of age at first birth in humans.

Background. Parental absences in childhood are often associated with accelerated reproductive maturity in humans. These results are counterintuitive for evolutionary social scientists because reductions in parental investment should be detrimental for offspring, but earlier reproduction is generally associated with higher fitness. In this paper we discuss a neglected hypothesis that early reproduction is often associated with parental absence because it decreases the average relatedness of a developing child to her future siblings. Family members often help each other reproduce, meaning that parents and offspring may find themselves in competition over reproductive opportunities. In these intergenerational negotiations offspring will have less incentive to help the remaining parent rear future half-siblings relative to beginning reproduction themselves. Method. We illustrate this "intergenerational conflict hypothesis" with a formal game-theoretic model. Results. We show that when resources constrain reproductive opportunities within the family, parents will generally win reproductive conflicts with their offspring, i.e., they will produce more children of their own and therefore delay existing offsprings' reproduction. This is due to the asymmetric relatedness between grandparents and grandchildren (r = .25), compared to siblings (r = 0.5), resulting in greater incentives for older siblings to help rear younger siblings than for grandparents to help rear grandchildren. However, if a parent loses or replaces their partner, the conflict between the parent and offspring becomes symmetric since half siblings are as related to one another as grandparents are to grandchildren. This means that the offspring stand to gain more from earlier reproduction when their remaining parent would produce half, rather than full, siblings. We further show that if parents senesce in a way that decreases the quality of their infant relative to their offspring's infant, the intergenerational conflict can shift to favor the younger generation

A curvilinear effect of height on reproductive success in human males

Human male height is associated with mate choice and intra-sexual competition, and therefore potentially with reproductive success. A literature review (n = 18) on the relationship between male height and reproductive success revealed a variety of relationships ranging from negative to curvilinear to positive. Some of the variation in results may stem from methodological issues, such as low power, including men in the sample who have not yet ended their reproductive career, or not controlling for important potential confounders (e.g. education and income). We investigated the associations between height, education, income and the number of surviving children in a large longitudinal sample of men (n = 3,578; Wisconsin Longitudinal Study), who likely had ended their reproductive careers (e.g. > 64 years). There was a curvilinear association between height and number of children, with men of average height attaining the highest reproductive success. This curvilinear relationship remained after controlling for education and income, which were associated with both reproductive success and height. Average height men also married at a younger age than shorter and taller men, and the effect of height diminished after controlling for this association. Thus, average height men partly achieved higher reproductive success by marrying at a younger age. On the basis of our literature review and our data, we conclude that men of average height most likely have higher reproductive success than either short or tall men

The Lantern, 2016-2017

• Our Lady of Perpetual Virginity • Essential Terms for the Audience • Stories Untold • Jesus Camp • The Second Avenue Schmear • Driving to the Beach • Thanks, Alice • Decay • Peanut Butter Rhapsody • Transactions • Traffic • Sissy • Melting Wings • Ocean • Small Town Summer • Third Story • Family Trees • Mixed, Just Like Me • Sour Graves • How Sweet the Sound • Goodnight, Halfmoon • I\u27m Going to Ask Him How • Music • Pizza • Manhoodlike • Meditations From a Bunk Bed in a Home on Mount Pocono • Soft • Twilight\u27s Palette • The Oracle • Cynicism • River Ganges • Pinata Body and Hearing the Gun Shot • Song With No Music • Of Mornings Considering Womanhood • 10 Hours in Philadelphia • To Cut • Sachrang • Bavarian Wave Swinger • Irish Rain • Remembrances, Well • The Roses • Buttermilk • The Universe Will Always Listen if You Ask Her, Which is Why I Like Her More Than God • A Lukewarm Light • A Thought of Death • Hobson • Decaying Light • Window Women • Dead Bee • The Imagery • For Rent • Mona Lisa MMXVIhttps://digitalcommons.ursinus.edu/lantern/1185/thumbnail.jp

Social Class

Discussion of class structure in fifth-century Athens, historical constitution of theater audiences, and the changes in the comic representation of class antagonism from Aristophanes to Menander

The Perceived Benefits of Height: Strength, Dominance, Social Concern, and Knowledge among Bolivian Native Amazonians

Research in industrial countries suggests that, with no other knowledge about a person, positive traits are attributed to taller people and correspondingly, that taller people have slightly better socioeconomic status (SES). However, research in some non-industrialized contexts has shown no correlation or even negative correlations between height and socioeconomic outcomes. It remains unclear whether positive traits remain attributed to taller people in such contexts. To address this question, here we report the results of a study in a foraging-farming society of native Amazonians in Bolivia (Tsimane’)–a group in which we have previously shown little association between height and socioeconomic outcomes. We showed 24 photographs of pairs of Tsimane’ women, men, boys, and girls to 40 women and 40 men >16 years of age. We presented four behavioral scenarios to each participant and asked them to point to the person in the photograph with greater strength, dominance, social concern, or knowledge. The pairs in the photographs were of the same sex and age, but one person was shorter. Tsimane’ women and men attributed greater strength, dominance, and knowledge to taller girls and boys, but they did not attribute most positive traits to taller adults, except for strength, and more social concern only when women assessed other women in the photographs. These results raise a puzzle: why would Tsimane’ attribute positive traits to tall children, but not tall adults? We propose three potential explanations: adults’ expectations about the more market integrated society in which their children will grow up, height as a signal of good child health, and children’s greater variation in the traits assessed corresponding to maturational stages

Parental Height Differences Predict the Need for an Emergency Caesarean Section

More than 30% of all pregnancies in the UK require some form of assistance at delivery, with one of the more severe forms of assistance being an emergency Caesarean section (ECS). Previously it has been shown that the likelihood of a delivery via ECS is positively associated with the birth weight and size of the newborn and negatively with maternal height. Paternal height affects skeletal growth and mass of the fetus, and thus might also affect pregnancy outcomes. We hypothesized that the effect of newborn birth weight on the risk of ECS would decrease with increasing maternal height. Similarly, we predicted that there would be an increase in ECS risk as a function of paternal height, but that this effect would be relative to maternal height (i.e., parental height differences). We used data from the Millennium Cohort Study: a large-scale survey (N = 18,819 births) with data on babies born and their parents from the United Kingdom surveyed 9 to 12-months after birth. We found that in primiparous women, both maternal height and parental height differences interacted with birth weight and predicted the likelihood of an ECS. When carrying a heavy newborn, the risk of ECS was more than doubled for short women (46.3%) compared to tall women (21.7%), in agreement with earlier findings. For women of average height carrying a heavy newborn while having a relatively short compared to tall partner reduced the risk by 6.7%. In conclusion, the size of the baby, the height of the mother and parental height differences affect the likelihood of an ECS in primiparous women