Granular Response to Impact: Topology of the Force Networks

Impact of an intruder on granular matter leads to formation of mesoscopic force networks seen particularly clearly in the recent experiments carried out with photoelastic particles, e.g., Clark et al., Phys. Rev. Lett., 114 144502 (2015). These force networks are characterized by complex structure and evolve on fast time scales. While it is known that total photoelastic activity in the granular system is correlated with the acceleration of the intruder, it is not known how the structure of the force network evolves during impact, and if there is a dominant features in the networks that can be used to describe intruder's dynamics. Here, we use topological tools, in particular persistent homology, to describe these features. Persistent homology allows quantification of both structure and time evolution of the resulting force networks. We find that there is a clear correlation of the intruder's dynamics and some of the topological measures implemented. This finding allows us to discuss which properties of the force networks are most important when attempting to describe intruder's dynamics. Regarding temporal evolution of the networks, we are able to define the upper bound on the relevant time scale on which the networks evolve

Long-Term Consequences of Congestion Pricing: A Small Cordon in the Hand Is Worth Two in the Bush

We evaluate and compare the long-term economic effects of three cordon-based road pricing schemes applied to the Washington, DC, metropolitan area. To conduct this analysis, we employ a spatially disaggregated general equilibrium model of a regional economy that incorporates the decisions of residents, firms, and developers, integrated with a spatially disaggregated strategic transportation planning model that features mode, time period, and route choice. We find that all cordon pricing schemes increase welfare of the residents, as well as lead to GDP growth. At the optimum, the larger cordon and a double cordon lead to higher benefits than the small cordon encompassing downtown core. Nevertheless, the small cordon seems to be a safer bet because when the toll charge is set suboptimally, the net benefits from the small cordon compared to the optimum change negligibly, while the net benefits from the larger cordon decline sharply as the charge deviates from the optimal level.traffic congestion, cordon tolls, land use, welfare analysis, road pricing, general equilibrium, simulation, Washington DC

Konsep Diri Penderita Hemofilia di Pekanbaru dalam Perspektif Fenomenologi

Hemophiliacs in Pekanbaru, with all the limitations that they have still capable to perform and complete their daily chores that require physical activity. For hemophiliacs, doing physical activity just like people in general will be harder, because when they do those physical activities, the joints in some parts of their body will ache and raise the bruises, this is caused by a lack of blood clotting factor. This study aims to determine the components of perceptual , conceptual component , the component attitudes, and communication experience hemophiliacs in PekanbaruThis study uses qualitative research methodology by conducting phenomenological approach. Subjects in this study consist of five people. Data collection techniques are grouped into three sections, which are; in-depth interviews, participant observation, and documentation. This study uses the Miles and Hubermen model of interactive data analysis system, by using the validity checking technique of the data through the extension of participation and triangulation.The result of this study showed that people with hemophilia in Pekanbaru if we look from the positive side of its perceptual components are just like people in general, they are cheerful, comfortable with their environment and there is no sense of shame, while its negative side is they sometimes less grateful and feel embarrassed. In the view of the positive side of its conceptual components, hemophilia sufferers tend to be responsible, humorous, rarely feel sad and often confident, but its negative side can be seen from a more reserved attitude. Then, focusing on the attitude component, the positive side which is owned by hemophiliacs is their friendly act, pleasant and helpful, but the fear of being alienated is the negative side of the patient. Meanwhile, based on the experience of communication, hemophiliacs in Pekanbaru have been able to implement a good and pleasant communication such as a sense of pride and pleasure, acceptance and friendship and more attention from the family, but there is a little less pleasant communication experience such as a fear of the opposite sex, discrimination and verbal or non-verbal harassment.Keywords: Self-concept, phenomenology, and hemophil

Penentuan Waktu Optimum dalam Pembuatan Bioetanol dari Bonggol Pisang Tanduk(Musa Paradisiaca Formatypisa) melalui Fermentasi

Banana tuber contains 76% starch as a source of organic material that can be changed to bioethanol which is an alternative of fuel oil. This study aimed to determine the optimum time of fermentation in the process of producing bioethanol from banana (musa paradisiaca formatypisa) tuber. In this study the fermentation of banana tuber is determined using saccharomyces cereviseae with the variation time of 3, 4, 5, 6, 7, 8 and 10 days. The stages carried out in this study were preliminary or sample preparation, delignification, hydrolysis, fermentation and separation. Bioethanol from the fermented ricestraw was analyzed using alcoholmeter. The content of bioethanol product increased on days 3 to 7 and reach the optimum on the day 7 which was 8.90%, where on the day 8 and 10 decreased the ethanol content