Sediment removal by prairie filter strips in row-cropped ephemeral watersheds

Twelve small watersheds in central Iowa were used to evaluate the effectiveness of prairie filter strips (PFS) in trapping sediment from agricultural runoff. Four treatments with PFS of different size and location (100% rowcrop, 10% PFS of total watershed area at footslope, 10% PFS at footslope and in contour strips, 20% PFS at footslope and in contour strips) arranged in a balanced incomplete block design were seeded in July 2007. All watersheds were in bromegrass ( L.) for at least 10 yr before treatment establishment. Cropped areas were managed under a no-till, 2-yr corn ( L.)-soybean [ (L.) Merr.] rotation beginning in 2007. About 38 to 85% of the total sediment export from cropland occurred during the early growth stage of rowcrop due to wet field conditions and poor ground cover. The greatest sediment load was observed in 2008 due to the initial soil disturbance and gradually decreased thereafter. The mean annual sediment yield through 2010 was 0.36 and 8.30 Mg ha for the watersheds with and without PFS, respectively, a 96% sediment trapping efficiency for the 4-yr study period. The amount and distribution of PFS had no significant impact on runoff and sediment yield, probably due to the relatively large width (37-78 m) of footslope PFS. The findings suggest that incorporation of PFS at the footslope position of annual rowcrop systems provides an effective approach to reducing sediment loss in runoff from agricultural watersheds under a no-till system

The Hamiltonian limit of (3+1)D SU(3) lattice gauge theory on anisotropic lattices

The extreme anisotropic limit of Euclidean SU(3) lattice gauge theory is examined to extract the Hamiltonian limit, using standard path integral Monte Carlo (PIMC) methods. We examine the mean plaquette and string tension and compare them to results obtained within the Hamiltonian framework of Kogut and Susskind. The results are a significant improvement upon previous Hamiltonian estimates, despite the extrapolation procedure necessary to extract observables. We conclude that the PIMC method is a reliable method of obtaining results for the Hamiltonian version of the theory. Our results also clearly demonstrate the universality between the Hamiltonian and Euclidean formulations of lattice gauge theory. It is particularly important to take into account the renormalization of both the anisotropy, and the Euclidean coupling $\beta_E$, in obtaining these results.Comment: 10 pages, 11 figure

Backward pion-nucleon scattering

A global analysis of the world data on differential cross sections and polarization asymmetries of backward pion-nucleon scattering for invariant collision energies above 3 GeV is performed in a Regge model. Including the $N_\alpha$, $N_\gamma$, $\Delta_\delta$ and $\Delta_\beta$ trajectories, we reproduce both angular distributions and polarization data for small values of the Mandelstam variable $u$, in contrast to previous analyses. The model amplitude is used to obtain evidence for baryon resonances with mass below 3 GeV. Our analysis suggests a $G_{39}$ resonance with a mass of 2.83 GeV as member of the $\Delta_{\beta}$ trajectory from the corresponding Chew-Frautschi plot.Comment: 12 pages, 16 figure

A dynamic power-aware partitioner with task migration for multicore embedded systems

Nowadays, a key design issue in embedded systems is how to reduce the power consumption, since batteries have a limited energy budget. For this purpose, several techniques such as Dynamic Voltage Scaling (DVS) or task migration can be used. DVS allows reducing power by selecting the optimal voltage supply, while task migration achieves this effect by balancing the workload among cores. This paper first analyzes the impact on energy due to task migration in multicore embedded systems with DVS capability and using the well-known Worst Fit (WF) partitioning heuristic. To reduce overhead, migrations are only performed at the time that a task arrives to and/or leaves the system and, in such a case, only one migration is allowed. The huge potential on energy saving due to task migration, leads us to propose a new dynamic partitioner, namely DP, that migrates tasks in a more efficient way than typical partitioners. Unlike WF, the proposed algorithm examines which is the optimal target core before allowing a migration. Experimental results show that DP can improve energy consumption in a factor up to 2.74 over the typical WF algorithm. © 2011 Springer-Verlag.This work was supported by Spanish CICYT under Grant TIN2009-14475-C04-01, and by Consolider-Ingenio under Grant CSD2006-00046.March Cabrelles, JL.; Sahuquillo Borrás, J.; Petit Martí, SV.; Hassan Mohamed, H.; Duato Marín, JF. (2011). A dynamic power-aware partitioner with task migration for multicore embedded systems. En Euro-Par 2011 Parallel Processing. Springer Verlag (Germany). 2011(6852):218-229. https://doi.org/10.1007/978-3-642-23400-2_21S21822920116852AlEnawy, T.A., Aydin, H.: Energy-Aware Task Allocation for Rate Monotonic Scheduling. In: Proceedings of the 11th Real Time on Embedded Technology and Applications Symposium, March 7-10, pp. 213–223. IEEE Computer Society, San Francisco (2005)Aydin, H., Yang, Q.: Energy-Aware Partitioning for Multiprocessor Real-Time Systems. In: Proceedings of the 17th International Parallel and Distributed Processing Symposium, Workshop on Parallel and Distributed Real-Time Systems, April 22-26, p. 113. IEEE Computer Society, Nice (2003)Baker, T.P.: An Analysis of EDF schedulability on a multiprocessor. IEEE Transactions on Parallel and Distributed Systems 16(8), 760–768 (2005)Brandenburg, B.B., Calandrino, J.M., Anderson, J.H.: On the Scalability of Real-Time Scheduling Algorithms on Multicore Platforms: A Case Study. In: Proceedings of the 29th Real-Time Systems Symposium, November 30-December 3, pp. 157–169. IEEE Computer Society, Barcelona (2008)Brião, E., Barcelos, D., Wronski, F., Wagner, F.R.: Impact of Task Migration in NoC-based MPSoCs for Soft Real-time Applications. In: Proceedings of the International Conference on VLSI, October 15-17, pp. 296–299. IEEE Computer Society, Atlanta (2007)Cazorla, F., Knijnenburg, P., Sakellariou, R., Fernández, E., Ramirez, A., Valero, M.: Predictable Performance in SMT Processors: Synergy between the OS and SMTs. IEEE Transactions on Computers 55(7), 785–799 (2006)Donald, J., Martonosi, M.: Techniques for Multicore Thermal Management: Classification and New Exploration. In: Proceedings of the 33rd Annual International Symposium on Computer Architecture, June 17-21, pp. 78–88. IEEE Computer Society, Boston (2006)El-Haj-Mahmoud, A., AL-Zawawi, A., Anantaraman, A., Rotenberg, E.: Virtual Multiprocessor: An Analyzable, High-Performance Architecture for Real-Time Computing. In: Proceedings of the International Conference on Compilers, Architectures and Synthesis for Embedded Systems, September 24-27, pp. 213–224. ACM Press, San Francisco (2005)Hung, C., Chen, J., Kuo, T.: Energy-Efficient Real-Time Task Scheduling for a DVS System with a Non-DVS Processing Element. In: Proceedings of the 27th Real-Time Systems Symposium, December 5-8, pp. 303–312. IEEE Computer Society, Rio de Janeiro (2006)Kalla, R., Sinharoy, B., Tendler, J.M.: IBM Power5 Chip: A Dual-Core Multithreaded Processor. IEEE Micro 24(2), 40–47 (2004)Kato, S., Yamasaki, N.: Global EDF-based Scheduling with Efficient Priority Promotion. In: Proceedings of the 14th International Conference on Embedded and Real-Time Computing Systems and Applications, August 25-27, pp. 197–206. IEEE Computer Society, Kaohisung (2008)Malardalen Real-Time Research Center, Vasteras, Sweden: WCET Analysis Project. WCET Benchmark Programs (2006), [Online], http://www.mrtc.mdh.se/projects/wcet/March, J., Sahuquillo, J., Hassan, H., Petit, S., Duato, J.: A New Energy-Aware Dynamic Task Set Partitioning Algorithm for Soft and Hard Embedded Real-Time Systems. To be published on The Computer Journal (2011)McNairy, C., Bhatia, R.: Montecito: A Dual-Core, Dual-Thread Itanium Processor. IEEE Micro 25(2), 10–20 (2005)Seo, E., Jeong, J., Park, S., Lee, J.: Energy Efficient Scheduling of Real-Time Tasks on Multicore Processors. IEEE Transactions on Parallel and Distributed Systems 19(11), 1540–1552 (2008)Shah, A.: Arm plans to add multithreading to chip design. ITworld (2010), [Online], http://www.itworld.com/hardware/122383/arm-plans-add-multithreading-chip-designUbal, R., Sahuquillo, J., Petit, S., López, P.: Multi2Sim: A Simulation Framework to Evaluate Multicore-Multithreaded Processors. In: Proceedings of the 19th International Symposium on Computer Architecture and High Performance Computing, October 24-27, pp. 62–68. IEEE Computer Society, Gramado (2007)Watanabe, R., Kondo, M., Imai, M., Nakamura, H., Nanya, T.: Task Scheduling under Performance Constraints for Reducing the Energy Consumption of the GALS Multi-Processor SoC. In: Proceedings of the Design Automation and Test in Europe, April 16-20, pp. 797–802. ACM, Nice (2007)Wei, Y., Yang, C., Kuo, T., Hung, S.: Energy-Efficient Real-Time Scheduling of Multimedia Tasks on Multi-Core Processors. In: Proceedings of the 25th Symposium on Applied Computing, March 22-26, pp. 258–262. ACM, Sierre (2010)Wu, Q., Martonosi, M., Clark, D.W., Reddi, V.J., Connors, D., Wu, Y., Lee, J., Brooks, D.: A Dynamic Compilation Framework for Controlling Microprocessor Energy and Performance. In: Proceedings of the 38th Annual IEEE/ACM International Symposium on Microarchitecture, November 12-16, pp. 271–282. IEEE Computer Society, Barcelona (2005)Zheng, L.: A Task Migration Constrained Energy-Efficient Scheduling Algorithm for Multiprocessor Real-time Systems. In: Proceedings of the International Conference on Wireless Communications, Networking and Mobile Computing, September 21-25, pp. 3055–3058. IEEE Computer Society, Shanghai (2007

Strong Decays of Strange Quarkonia

In this paper we evaluate strong decay amplitudes and partial widths of strange mesons (strangeonia and kaonia) in the 3P0 decay model. We give numerical results for all energetically allowed open-flavor two-body decay modes of all nsbar and ssbar strange mesons in the 1S, 2S, 3S, 1P, 2P, 1D and 1F multiplets, comprising strong decays of a total of 43 resonances into 525 two-body modes, with 891 numerically evaluated amplitudes. This set of resonances includes all strange qqbar states with allowed strong decays expected in the quark model up to ca. 2.2 GeV. We use standard nonrelativistic quark model SHO wavefunctions to evaluate these amplitudes, and quote numerical results for all amplitudes present in each decay mode. We also discuss the status of the associated experimental candidates, and note which states and decay modes would be especially interesting for future experimental study at hadronic, e+e- and photoproduction facilities. These results should also be useful in distinguishing conventional quark model mesons from exotica such as glueballs and hybrids through their strong decays.Comment: 69 pages, 5 figures, 39 table

Abelian-Projected Effective Gauge Theory of QCD with Asymptotic Freedom and Quark Confinement

We give an outline of a recent proof that the low-energy effective gauge theory exhibiting quark confinement due to magnetic monopole condensation can be derived from QCD without any specific assumption. We emphasize that the low-energy effective abelian gauge theories obtained here give the dual description of the same physics in the low-energy region. They show that the QCD vacuum is nothing but the dual (type II) superconductor.Comment: 15 pages, Latex, no figures, Talk given at YKIS'97, Non-perturbative QCD, Kyot