bluuebunny/crossref_metadata_2025_split huggingface dataset:
New interpolation paradigm for the design of ship profile
Authors: Mihai Bica Alexandru , Laslo Eugen 
Published: September 2019

Abstract
A new interpolation technique based on an optimized near end-points Akima’s cubic spline method is proposed in order to plot the profile of longitudinal section in a boat such that the aerodynamic properties will be improved. As a result of the method, the boat shape permit to reduce the water resistance in the forward motion. The method is illustrated by simulating the boat shape using the proposed method in comparison with the shapes provided by the natural cubic spline and by the Akima’s cubic spline interpolation procedures.
Utilisation of the minimum paths in networks for transport terminals
Authors: Popa E. , Ghionea F. 
Published: September 2019

Abstract
The reason behind this material consisted in the lack of similarity between complementary issues in a field that includes graphs and networks. For example, a theoretical network problem pretends to determine the minim number of nodes which must be excluded to remove all the grid links, a practical network problem claims to determine the shortest route between 2 nodes when it knows the length of each link. In a strange nod the first problem has a maximum solution, whereas the second problem has no maxim solution (only if the network is oriented and do not allow circuits, conditions that take out the issue from the general sphere, drastically customizing it. The first problem can also develop in the situation in which the issue is to exclude all arcs, less one and almost symptomatic: there was no procedure to offer the second minimum path in the graph. Here, it is proposed a modality to find the second minimum path avoiding the complete enumeration of paths between the 2 nodes taken in consideration. The study case presented in this paper is based on railway terminals-Gara de Nord’s traffic - after the first shortest way for stabling which will be the next, and also this type of application can be used on the efficiency of maritime berth. The utility of the idea concerning the second minimal path is found in the current exploitation of almost any transport system (for e.g. the review of the initial planning, when the established side-tracking in receiving board from the final station cannot be used for intensive traffic reasons, or receiving the train at to another line must be done so as all the future movement of the traffic circulation or train wagon marshal to mess as little as possible the set of movements necessary for further exploitation, receiving the bus to another platform because the first platform is busy with a defective bus).
Mesh independence of a transient multiphase fluid-solid interaction
Authors: Chirica I , Angheluta C M , Perijoc S D , Hobjilă A I , Frătita M 
Published: September 2019

Abstract
To prepare for a transient analysis of a damaged ship, a mesh independence test was carried out on an open channel free surface simulation with fluid-solid interaction. The numerical methods applied, the mesh sizing and method, as well as several other parameters which might influence the results were adjusted to obtain comparisons and establish the proper solution for the upcoming simulation. Compared data includes the drag force, dynamic and total pressure applied to the solid, as well as the maximum free surface elevation at the solid domain.
The 2019 Netherlands Model BIT: riding the new investment treaty waves
Authors: Duggal Kabir A N , van de Ven Laurens H 
Published: September 2019

Abstract
Investor–state arbitration is undergoing a paradigm shift with several countries and regional blocs rethinking the best way to protect investor rights while retaining sovereign prerogatives. This is where the Netherlands fits into the narrative. Its decision to modernize appears to follow the contemporary developments in investment arbitration, including heightened public scrutiny on the effect of investment treaties on regulatory space and the investor-to-state dispute settlement system, as well as the Post-Treaty of Lisbon European Union framework for investment arbitration. On 16 May 2018, the Dutch Ministry of Foreign Affairs published a draft for a new Model Bilateral Investment Treaty (BIT) on the Government’s website. This was done with a view to updating the earlier Model BIT which dates. Through public consultation, individuals and interest groups were invited to share their views. The Government amended the 2018 Draft Model BIT after deliberating on the public reactions it had received, and circulated a new draft on 19 October 2018. Subsequently, after parliamentary debate in February 2019, the Dutch Government published an updated Model BIT on 22 March 2019. In this article, we critically examine the 2019 Final Dutch Model BIT and examine it in light of the global rethink on investment law and policy.
Temporal Changes in Habitat Selection and Nest Spacing in a Colony of Ross' and Lesser Snow Geese
Authors: McLandress M. Robert 
Published: September 2019

Abstract
I studied the nesting colony of Ross' Geese (Chen rossii) and Lesser Snow Geese (C. caerulescens caerulescens) at Karrak Lake in the central Arctic of Canada in the summer of 1976. Related studies indicated that this colony had grown from 18,000 birds in 1966-1968 to 54,500 birds in 1976. In 1976, geese nested on islands that were used in the late 1960's and on an island and mainland sites that were previously unoccupied. Average nest density in 1976 was three-fold greater than in the late 1960's. Consequently, the average distance to nearest neighbors of Ross' Geese in 1976 was half the average distance determined 10 yr earlier.
The mean clutch size of Ross' Geese was greater in island habitats where nest densities were high than in less populated island or mainland habitats. The average size of Snow Goose clutches did not differ significantly among island habitats but was larger at island than at mainland sites. Large clutches were most likely attributable to older and/or earlier nesting females. Habitat preferences apparently differed between species. Small clutches presumably indicated that young geese nested in areas where nest densities were low. The establishment of mainland nesting at Karrak Lake probably began with young Snow Geese using peripheral areas of the colony. Young Ross' Geese nested in sparsely populated habitats on islands to a greater extent than did Snow Geese. Ross' Geese also nested on the mainland but in lower densities than Ross' Geese nesting in similar island habitats. Successful nests with the larger clutches had closer conspecific neighbors than did successful nests with smaller clutches. The species composition of nearest neighbors changed significantly with distance from Snow Goose nests but not Ross' Goose nests. Nesting success was not affected by the species of nearest neighbor, however. Because they have complementary antipredator adaptations, Ross' and Snow geese may benefit by nesting together.
Speciation in Sapsuckers (Sphyrapicus): I. Genetic Differentiation
Authors: Johnson Ned K. , Zink Robert M. 
Published: September 2019

Abstract
We report the results of an electrophoretic analysis at 39 presumptive genetic loci of 88 specimens in the picid genus Sphyrapicus, here treated as comprising the following species: Williamson's Sapsucker (S. thyroideus), Yellow-bellied Sapsucker (S. varius), Red-naped Sapsucker (S. nuchalis), and Red-breasted Sapsucker (S. ruber). Seventeen loci (43.5%) were polymorphic. Values for observed heterozygosity in S. ruber ruber, S. ruber daggetti, and in three populations of S. nuchalis were uniform and averaged 0.043, the mean value reported for other birds. However, S. varius, at 0.022, and S. thyroideus, at 0.016, have low values of H. Values for percentage of polymorphic loci ranged from 12.8 to 20.5 in S. ruber and S. nuchalis, 12.8 in S. varius, and 7.7 in S. thyroideus. In contrast, all four species exhibited a similar mean number of alleles per locus (1.12-1.21). Genetic distances between populations of the same species are either very low or zero. Genetic distances are also very low between the phenotypically dissimilar ruber and nuchalis (D̄ = 0.004), two forms we consider to be biological species based on their assortative mating in sympatry. This is the lowest avian interspecific D-value ever reported and is similar to that found between avian subspecies. Phenotypically, varius and nuchalis are very similar, yet the average genetic distance between samples of these forms, 0.029, is comparable to interspecific values reported for other avian congeners and is our chief basis for treating the two forms as separate species. S. thyroideus is strongly differentiated genetically from varius (D̄ = 0.142), from nuchalis (D̄ = 0.197), and from ruber (D̄ = 0.186). FST statistics point to little or no population subdivision within ruber and nuchalis but substantial subdivision within the superspecies varius (S. varius + S. nuchalis + S. ruber). The genetic information suggests that the Williamson's Sapsucker represents the oldest lineage in the genus. S. thyroideus split from its sister clade (superspecies S. varius) between 3 and 4 MYBP. S. ruber and S. nuchalis are sister species that evolved very recently, either during or since the Pleistocene and sometime after their common ancestor diverged from S. varius.
Variation in Incubation Period within a Population of the European Starling
Authors: Ricklefs Robert E. , Smeraski Cynthia A. 
Published: September 2019

Abstract
We switched eggs among nests of European Starlings soon after the eggs were laid, and we measured incubation periods to within 2 h in most cases. Data from two years were analyzed to determine how much the natural parent of the egg and the incubating parent contributed to variation in the length of the incubation period. In one year, the relative size and composition of the yolk of one egg from each clutch were measured in order to assess the additional influence of egg composition on the length of the incubation period. In both sets of experiments, nest (incubating parent) had a significant effect, whereas clutch (natural parent) had either no effect or a marginally significant effect on the length of the incubation period. The standard deviation of incubation periods within nests was 2.6 and 3.5 h in the two experiments. Incubation periods increased significantly both with the percentage of yolk in eggs laid by the natural parent and with the percentage of yolk in eggs laid by the incubating parent.
Our results suggest that the length of the incubation period is determined primarily by the incubating behavior of the adult, thermal properties of the nest, or both. Genetic differences in the growth rates of embryos and maternal effects expressed through egg composition were small and generally insignificant. Incubation period was, however, weakly related to egg composition of both the natural parent and the incubating parent, suggesting a phenotypic correlation between egg formation and incubation behavior.
Dominance Relations, Resource Use, and Pairing Chronology of Gadwalls in Winter
Authors: Paulus Stuart L. 
Published: September 2019

Abstract
I studied pairing chronology and agonistic displays of Gadwalls (Anas strepera) and spatial associations among Gadwalls and other Anatinae in the coastal marshes of southwestern Louisiana from October 1977 through April 1978. Gadwalls began arriving in Louisiana in late September, but by mid-October 45% of females were paired and by late November 81% were paired. The percentage of paired females increased slowly to 90% in April. Bill threats were the predominant agonistic display of Gadwalls, accounting for 89% of all observations, while chasing (5.8%) and biting (5.2%) accounted for the remainder. Nearly all (91.1%) conflicts involved birds that had been feeding before the dispute. On average, Gadwalls spent 0.4% of their time in agonistic activities. Gadwalls preferred to associate with individuals of similar pair status. Paired Gadwalls were more likely to threaten other paired birds, and unpaired Gadwalls other unpaired birds, than they would individuals of the other pair status. Only 14% of disputes involving Gadwalls were with other Anatinae. Pairs were considered dominant over unpaired birds, as pairs won 81% (P < 0.001) of contests with unpaired birds. This study suggested that paired birds, because of their dominance, probably had greater access to preferred food resources and were more successful in meeting nutrient requirements than were unpaired birds. It also suggested that pairing chronology in Anatinae may be related to food choice and foraging strategies, those species feeding on poorer-quality foods forming pairs earlier, as individuals attempt to optimize their allocation of time for feeding and other activities.
Geographical Correlates of Abundance vs. Rarity in Some North American Winter Landbirds
Authors: Bock Carl E. 
Published: September 2019

Abstract
Using Christmas Bird Count (CBC) data, I compared range sizes and within-range abundances of 70 species of apodiform, piciform, and passerine landbirds whose ranges are 75% or more restricted in winter to the contiguous U.S. and southern Canada. Range size was computed as the number of occupied 5Â° latitude-longitude blocks. Three abundance measures were calculated: (1) mean birds counted/census hour across all occupied blocks, (2) maximum birds/hour in a single block, and (3) maximum birds/hour on a single CBC. Range size was positively but weakly correlated with each abundance measure, and the abundance measures were very strongly correlated with one another. Geography was a powerful predictor of the species' positions in a two-dimensional space difined by the axes of range size and average within-range abundance. Taxa that breed and winter at higher latitudes had larger total populations, and had significantly larger ranges and average local abundances. Species grouped by longitudinal areas of greatest local abundance had distinct range sizes but did not differ in average within-range abundance. Eastern species had larger ranges than comparably abundant western forms, probably because the eastern U.S. is characterized by relatively widespread habitat types. Results of this study suggest that a species' within-range abundance is influenced by the degree of its habitat generalization, whereas its range size will be larger if it is a habitat generalist or a specialist on widespread habitats. Because individual CBC's include many habitats, the same ecological attribute-habitat generalization-could cause species to be both widespread and abundant inside CBC circles. Carefully standardized within-habitat censuses will be required to determine whether or not these generalist species also dominate the individual habitats occupied by their more specialized and narrowly distributed relatives.
Reliability of Singing Bird Surveys: Changes in Observer Efficiency with Avian Density
Authors: Bart Jonathan , Schoultz James D. 
Published: September 2019

Abstract
Field trials in which paired observers were used and indoor simulations in which recorded bird songs were used indicated that, as the number of singing birds audible from a listening station increased from 1 to 4, the fraction of them recorded by observers declined by up to 50%. This reduction in efficiency violates one of the basic assumptions of any index-that the proportion of animals detected remains constant-and could cause surveyors who rely primarily on auditory cues to underestimate changes in population density by up to 25% for common species and 33% for abundant species. The change in efficiency, which is best regarded as measurement error, cannot be detected by a statistical examination of the data and thus may pass undetected in many field studies. It seems unlikely that any general procedure for "correcting" the error would be reliable. The results indicate that singing bird surveys of common species should be supplemented by other methods if accurate estimates of changes in density are needed. A general conclusion of the study is that whenever animals "compete" for a place in the survey, for example by filling up traps or suppressing one another's songs, then the index tends to underestimate a change in density. If efficiency increases with density, then the survey tends to overestimate a change in density. If the sign of the bias can be determined, the survey can be used to provide a minimum or maximum estimate of a change in density even if the magnitude of the bias cannot be estimated.
An Evaluation of Time-Budget Estimates of Daily Energy Expenditure in Birds
Authors: Weathers Wesley W. , Buttemer William A. , Hayworth Anita M. , Nagy Kenneth A. 
Published: September 2019

Abstract
We used the doubly-labeled water (DLW) technique to measure the daily energy expenditure (ḢTD) of aviary-housed Loggerhead Shrikes (Lanius ludovicianus). Simultaneously to our DLW measurements, we obtained a continuous 24-h record of the bird's time budget (TB) and assessed its thermal environment at 10-min intervals with an array of 23 meteorological sensors that measured the air temperature (Ta), operative temperature (Te), and wind speed (u) experienced by the bird. From the TB and meteorological data, we estimated the birds' ḢTV by several TB models that differed in the energy equivalents assigned to behaviors and in how thermoregulatory costs were calculated. Only a convection-adjusted, electrical-analog model provided a mean ḢTV estimate that was identical to the mean DLW value (106 kJ/day). Values of $\dot{H}_{TD}$ for individual birds calculated by this model ranged from -8.1 to +7.5% of the DLW values and were significantly correlated with the DLW values, indicating that this method accurately gauged the ḢTV of individual birds. Our analysis showed that this model's accuracy resulted from (1) using Te and u to calculate thermoregulatory costs through heat transfer theory, and (2) using measured energy equivalents for the various behavior categories. ḢTV estimates based on other commonly used TB models differed significantly from the DLW values, with mean errors ranging from -18 to +21%.
Territory Size Variations in Shrubsteppe Birds
Authors: Wiens John A. , Rotenberry John T. , Horne Beatrice Van 
Published: September 2019

Abstract
We recorded variations in sizes of breeding territories of Sage (Amphispiza belli) and Brewer's (Spizella breweri) sparrows at four locations in shrubsteppe habitats during 1976-1983. There was considerable variation in territory sizes of both species, and ANOVA tests indicated that site, plot within site, and year all contributed to this variation. Territory-size variations of Sage Sparrows were correlated with differences in several habitat features, while those of Brewer's Sparrows showed no relation to habitat variation. Territory sizes in both species varied inversely with breeding population densities, although in different ways. Our findings cast doubt on the meaning or value of "average" territory-size measures for a species as a whole.
Seasonal Changes in Feeding Success, Activity Patterns, and Weights of Nonbreeding Sanderlings (Calidris alba)
Authors: Maron J. L. , Myers J. P. 
Published: September 2019

Abstract
Seasonal changes in Sanderling (Calidris alba) feeding success, time budgets, and weights were followed throughout the nonbreeding season at Bodega Bay, California. Sanderlings spent more time roosting in fall than in winter, and in fall adults spent more time roosting than juveniles. Sanderling prey capture rates were high in fall and spring and declined through winter. Sanderling weights paralleled seasonal changes in feeding success and activity patterns: birds were heaviest in fall and spring and lightest in winter. These results reflect lowered food availability in winter and imply that birds may have difficulty balancing their energy budgets during part of the nonbreeding season.
Recognition of Parents' Voices by Young Cliff Swallows
Authors: Beecher Michael D. , Stoddard Philip K. , Loesche Patricia 
Published: September 2019

Abstract
Cliff Swallow (Hirundo pyrrhonota) chicks were played calls of parents and unrelated (control) adults at 9 and 18 days of age. Younger chicks showed no difference in the frequency of their antiphonal begging calls to parental vs. control calls. The older, near-fledging chicks, however, responded significantly more to parental calls than to control calls: 78% of their total antiphonal calls were in response to parental playback calls. In these older chicks, the degree of preference correlated with the measured acoustic differences between the parent and control calls. The results indicate that Cliff Swallow chicks are able to recognize their parents by voice before they leave the nest. Offspring recognition of parents is discussed as it relates to the evolution of parent-offspring recognition systems in general.
Parental Investment by the Northern Mockingbird: Male and Female Roles in Feeding Nestlings
Authors: Breitwisch Randall , Merritt Peter G. , Whitesides George H. 
Published: September 2019

Abstract
Analysis of 3,293 feeding trips to nestling Northern Mockingbirds (Mimus polyglottos) in the first 11 days of nestling life showed that males and females fed young at similar rates. Young were fed a mixed diet of animal prey and fruits, and males and females fed similar volumes of animal prey and of fruits. Females displayed a monotonic increase in feeding rate during nestling life but did not significantly increase load size. Males significantly increased both feeding rate and load size with age of nestlings, and their feeding rate peaked in the mid-nestling period, when young grow most rapidly. Males and females fed broods of two and three young at similar rates. There was a biased breeding-adult sex ratio in this population, with males outnumbering females. The unbalanced sex ratio may allow females to demand a high level of male parental care in feeding nestlings and in other behaviors included in parental investment.
Family Associations in Communally Roosting Black Vultures
Authors: Rabenold Patricia Parker 
Published: September 2019

Abstract
Observations of marked individuals in a partially marked population of Black Vultures (Coragyps atratus) show that immediate family members maintain close contact throughout the year. Associations between mates and between parents and offspring are primarily responsible for this. Mutual allopreening, feedings, and intercessions in fights occur almost exclusively within families. Adults known to breed within the study area (neighbors) associate more strongly than nonneighbors, although not as strongly as mates. Certain families associate preferentially with certain other families. Strength of interfamily associations is not related to distance between nest sites within the study area. I argue, therefore, that birds actively seek particular individuals as associates. Further knowledge of breeding dispersal of young of known parentage will provide clues to relatedness of highly associated neighbors. Strong associations among related individuals can help explain the use of avian communal roosts as information centers.