There is no MacWilliams identity for convolutional codes

An example is provided of two convolutional codes that have the same transmission gain but whose dual codes do not. This shows that no analog of the MacWilliams identity for block codes can exist relating the transmission gains of a convolutional code and its dual

2,4-D and Mycoleptodiscus terrestris for control of Eurasian Watermilfoil

Growth chamber studies were conducted to evaluate the impact of an indigenous fungal pathogen, Mycoleptodiscus terrestris (Gerd.) Ostazeski, and the herbicide 2,4-D applied alone and in combination with one another, on the growth of a nuisance submersed plant, Eurasian watermilfoil ( Myriophyllum spicatum L.)(PDF has 6 pages.

Male-Female Productivity Differentials: the Role of Ability and Incentives

We consider the response to incentives as an explanation for productivity differences within a firm that paid its workers piece rates. We provide a framework within which observed productivity differences can be decomposed into two parts: one due to differences in ability and the other due to differences in the response to incentives. We apply this decomposition to male and female workers a tree-planting firm in the province of British Columbia, Canada. We provide evidence that individuals do react differently to incentives. However, while the women in our sample reacted slightly more to incentives than did the men, the average difference is not statistically significant. The productivity differential that men enjoyed arose because of differences in ability, strength in our application.Productivity, Gender, Compensation, Incentives

Male-Female Productivity Differentials: the Role of Ability and Incentives (revised)

We consider the response to incentives as an explanation for productivity differences within a firm that paid its workers piece rates. We provide a framework within which observed productivity differences can be decomposed into two parts: one due to differences in ability and the other due to differences in the response to incentives. We apply this decomposition to male and female workers from a tree-planting firm in the province of British Columbia, Canada. We provide evidence that individuals do react differently to incentives. However, while the women in our sample reacted slightly more to incentives than did the men, the average difference is not statistically significant. The productivity differential that men enjoyed arose because of differences in ability, strength in our application.Productivity, Gender, Compensation, Incentives

Combustion of liquid sprays at high pressures

The combustion of pressure atomized fuel sprays in high pressure stagnant air was studied. Measurements were made of flame and spray boundaries at pressures in the range 0.1-9 MPa for methanol and n-pentane. At the higher test pressure levels, critical phenomena are important. The experiments are compared with theoretical predictions based on a locally homogeneous two-phase flow model. The theory correctly predicted the trends of the data, but underestimates flame and spray boundaries by 30-50 percent, indicating that slip is still important for the present experiments (Sauter mean diameters of 30 microns at atmospheric pressure under cold flow conditions). Since the sprays are shorter at high pressures, slip effects are still important even though the density ratio of the phases approach one another as the droplets heat up. The model indicates the presence of a region where condensed water is present within the spray and provides a convenient means of treating supercritical phenomena

A property of the colored complete graph

AbstractIf the lines of the complete graph Kn are colored so that no point is on more than 17(n−1) lines of the same color or so that each point lies on more than 17(5n+8) lines of different colors, then Kn contains a cycle of length n with adjacent lines having different colors

Social Media’s Impact on One’s Mental, Physical, and Emotional Well-being

Social media is widely used in users’ daily lives and is deeply embedded in the world of technology. Cellular devices and their applications have shown primarily negative effects on individuals’ lives. Studies have shown a lower self-esteem in young adults addicted to their smartphone (Aznar-Díaz, et al., et al. 2020). Another study highlighted the reactions to creating one’s own content versus the implications of consuming content. Individuals who created more than they consumed reported a higher level of self-esteem (Hygen, et al., 2021). While there were many studies regarding social media and wellness of young adults, there were gaps in research designed to find a way to make social media have the best impact on one\u27s life as possible. The purpose of this study was to find commonalities among the positive and negative relationships of social media to improve user experience with such applications as it relates to their daily lives. Findings included several themes regarding the positive and negative uses of social media. Participants reported stronger relationships, increased sense of self, and better experiences in using social media when curating their feed and following pages that post meaningful content. On the other hand, participants also reported the downsides of social media, which include comparing themselves to others, hyper accessibility to toxic posts and news reports, and seeking external validation from others

Employing pre-stress to generate finite cloaks for antiplane elastic waves

It is shown that nonlinear elastic pre-stress of neo-Hookean hyperelastic materials can be used as a mechanism to generate finite cloaks and thus render objects near-invisible to incoming antiplane elastic waves. This approach appears to negate the requirement for special cloaking metamaterials with inhomogeneous and anisotropic material properties in this case. These properties are induced naturally by virtue of the pre-stress. This appears to provide a mechanism for broadband cloaking since dispersive effects due to metamaterial microstructure will not arise.Comment: 4 pages, 2 figure