2,727 research outputs found

    Kajian Pemetaan Tingkat Kerawanan Banjir Dengan Menggunakan Sistem Informasi Geografis (Studi Kasus : DAS Beringin, Kota Semarang)

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    Flood is a common problem that occurs in some parts of Indonesia. Beringin River is one of the rivers in Semarang that contributed floods every year. Along as the development technology, then to determine level of flood conducted research by using 2 method, the weighting method and rational method. The research result were showed that condition of flood DAS Beringin commonly included in condition vulnerable with an area of 1795.003 hectares (59.89%). Level of risk flood with risk category an area of 875.441 hectares (29.21%) of the total DAS area. The level rather risk having percentace an area of 299.691 hectares (40.13%) and 22.566 hectares (0.75%). the higher level risk have percentage of the area of 4,441 hectares (0.1%) of total DAS area. Water runoff that occurs in village Sub -DAS 1 that generate highest discharge of 357.766 m3/sec (68.048%), Sub -DAS 2 maximum discharge of 124.964 m3/sec (23.769%), and the Sub -DAS 3 produces the lowest discharge is 43.0227 m3/sec (8.183%). Effect of the maximum discharge is the advanced factor of the result of land use and rainfall. At speed of high water occur fast and a little amount of water, resulting a high flow of water is flowing, so that the flow is very heavy and destructive impact

    Current and future technical, economic and environmental feasibility of maize and wheat residues supply for biomass energy application:Illustrated for South Africa

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    AbstractThis study assessed the feasibility of mobilising maize and wheat residues for large-scale bioenergy applications in South Africa by establishing sustainable residue removal rates and cost of supply based on different production regions. A key objective was to refine the methodology for estimating crop residue harvesting for bioenergy use, while maintaining soil productivity and avoiding displacement of competing residue uses. At current conditions, the sustainable bioenergy potential from maize and wheat residues was estimated to be about 104 PJ. There is potential to increase the amount of crop residues to 238 PJ through measures such as no till cultivation and adopting improved cropping systems. These estimates were based on minimum residues requirements of 2 t ha−1 for soil erosion control and additional residue amounts to maintain 2% SOC level.At the farm gate, crop residues cost between 0.9 and 1.7 GJ−1.About96 GJ−1. About 96% of these residues are available below 1.5 GJ−1. In the improved scenario, up to 85% of the biomass is below 1.3 GJ−1.Forbiomassdeliveriesattheconversionplant,about36 GJ−1. For biomass deliveries at the conversion plant, about 36% is below 5 GJ−1 while in the optimised scenario, about 87% is delivered below 5$ GJ−1. Co-firing residues with coal results in lower cost of electricity compared to other renewables and significant GHG (CO2 eq) emissions reduction (up to 0.72 tons MWh−1). Establishing sustainable crop residue supply systems in South Africa could start by utilising the existing agricultural infrastructure to secure supply and develop a functional market. It would then be necessary to incentivise improvements across the value chain

    Article Fast Track Disproportional Plastome-Wide Increase of Substitution Rates and Relaxed Purifying Selection in Genes of Carnivorous Lentibulariaceae

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    Abstract Carnivorous Lentibulariaceae exhibit the most sophisticated implementation of the carnivorous syndrome in plants. Their unusual lifestyle coincides with distinct genomic peculiarities such as the smallest angiosperm nuclear genomes and extremely high nucleotide substitution rates across all genomic compartments. Here, we report the complete plastid genomes from each of the three genera Pinguicula, Utricularia, and Genlisea, and investigate plastome-wide changes in their molecular evolution as the carnivorous syndrome unfolds. We observe a size reduction by up to 9% mostly due to the independent loss of genes for the plastid NAD(P)H dehydrogenase and altered proportions of plastid repeat DNA, as well as a significant plastome-wide increase of substitution rates and microstructural changes. Protein-coding genes across all gene classes show a disproportional elevation of nonsynonymous substitutions, particularly in Utricularia and Genlisea. Significant relaxation of purifying selection relative to noncarnivores occurs in the plastid-encoded fraction of the photosynthesis ATP synthase complex, the photosystem I, and in several other photosynthesis and metabolic genes. Shifts in selective regimes also affect housekeeping genes including the plastid-encoded polymerase, for which evidence for relaxed purifying selection was found once during the transition to carnivory, and a second time during the diversification of the family. Lentibulariaceae significantly exhibit enhanced rates of nucleotide substitution in most of the 130 noncoding regions. Various factors may underlie the observed patterns of relaxation of purifying selection and substitution rate increases, such as reduced net photosynthesis rates, alternative paths of nutrient uptake (including organic carbon), and impaired DNA repair mechanisms

    Exact Results for Kinetics of Catalytic Reactions

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    The kinetics of an irreversible catalytic reaction on substrate of arbitrary dimension is examined. In the limit of infinitesimal reaction rate (reaction-controlled limit), we solve the dimer-dimer surface reaction model (or voter model) exactly in arbitrary dimension DD. The density of reactive interfaces is found to exhibit a power law decay for D<2D<2 and a slow logarithmic decay in two dimensions. We discuss the relevance of these results for the monomer-monomer surface reaction model.Comment: 4 pages, RevTeX, no figure

    Mean-Field Analysis and Monte Carlo Study of an Interacting Two-Species Catalytic Surface Reaction Model

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    We study the phase diagram and critical behavior of an interacting one dimensional two species monomer-monomer catalytic surface reaction model with a reactive phase as well as two equivalent adsorbing phase where one of the species saturates the system. A mean field analysis including correlations up to triplets of sites fails to reproduce the phase diagram found by Monte Carlo simulations. The three phases coexist at a bicritical point whose critical behavior is described by the even branching annihilating random walk universality class. This work confirms the hypothesis that the conservation modulo 2 of the domain walls under the dynamics at the bicritical point is the essential feature in producing critical behavior different from directed percolation. The interfacial fluctuations show the same universal behavior seen at the bicritical point in a three-species model, supporting the conjecture that these fluctuations are a new universal characteristic of the model.Comment: 11 pages using RevTeX, plus 4 Postscript figures. Uses psfig.st

    Feedback control of arm movements using Neuro-Muscular Electrical Stimulation (NMES) combined with a lockable, passive exoskeleton for gravity compensation.

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    Within the European project MUNDUS, an assistive framework was developed for the support of arm and hand functions during daily life activities in severely impaired people. This contribution aims at designing a feedback control system for Neuro-Muscular Electrical Stimulation (NMES) to enable reaching functions in people with no residual voluntary control of the arm and shoulder due to high level spinal cord injury. NMES is applied to the deltoids and the biceps muscles and integrated with a three degrees of freedom (DoFs) passive exoskeleton, which partially compensates gravitational forces and allows to lock each DOE The user is able to choose the target hand position and to trigger actions using an eyetracker system. The target position is selected by using the eyetracker and determined by a marker-based tracking system using Microsoft Kinect. A central controller, i.e., a finite state machine, issues a sequence of basic movement commands to the real-time arm controller. The NMES control algorithm sequentially controls each joint angle while locking the other DoFs. Daily activities, such as drinking, brushing hair, pushing an alarm button, etc., can be supported by the system. The robust and easily tunable control approach was evaluated with five healthy subjects during a drinking task. Subjects were asked to remain passive and to allow NMES to induce the movements. In all of them, the controller was able to perform the task, and a mean hand positioning error of less than five centimeters was achieved. The average total time duration for moving the hand from a rest position to a drinking cup, for moving the cup to the mouth and back, and for finally returning the arm to the rest position was 71 s

    The Impact of Kaluza-Klein Excited W Boson on the Single Top at LHC and Comparison with other Models

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    We study the s-channel single top quark production at the LHC in the context of extra dimension theories, including the Kaluza-Klein (KK) decomposition. It is shown that the presence of the first KK excitation of WW gauge boson can reduce the total cross section of s-channel single top production considerably if MWKK∼2.2TeVM_{W_{KK}}\sim2.2 \rm TeV (3.5TeV3.5 \rm TeV) for 7TeV7\rm TeV (14TeV14\rm TeV) in proton-proton collisions. Then the results will be compared with the impacts of other beyond Standard Model (SM) theories on the cross section of single top s-channel. The possibility of distinguishing different models via their effects on the production cross section of the s-channel is discussed.Comment: 23 pages,6 figure

    The three species monomer-monomer model: A mean-field analysis and Monte Carlo study

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    We study the phase diagram and critical behavior of a one dimensional three species monomer-monomer surface reaction model. Static Monte Carlo simulations show a phase diagram consisting of a reactive steady state bordered by three equivalent unreactive phases where the surface is saturated with one monomer species. The transitions from the reactive to saturated phases are all continuous, while the transitions between poisoned phases are first-order, with bicritical points where the reactive phase meets two poisoned phases. A mean-field cluster analysis predicts all of the qualitative features of the phase diagram only when correlations up to triplets of adjacent sites are included. Dynamic Monte Carlo simulations show that the transition from the reactive to a saturated phase show critical behavior in the directed percolation universality class, while the bicritical point shows critical behavior in the even branching annihilating random walk class. The crossover from bicritical to critical behavior is also studied.Comment: 16 pages using RevTeX, plus 10 figures. Uses psfig.st
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