1,160 research outputs found

    Cohen-Macaulay graphs and face vectors of flag complexes

    Full text link
    We introduce a construction on a flag complex that, by means of modifying the associated graph, generates a new flag complex whose hh-factor is the face vector of the original complex. This construction yields a vertex-decomposable, hence Cohen-Macaulay, complex. From this we get a (non-numerical) characterisation of the face vectors of flag complexes and deduce also that the face vector of a flag complex is the hh-vector of some vertex-decomposable flag complex. We conjecture that the converse of the latter is true and prove this, by means of an explicit construction, for hh-vectors of Cohen-Macaulay flag complexes arising from bipartite graphs. We also give several new characterisations of bipartite graphs with Cohen-Macaulay or Buchsbaum independence complexes.Comment: 14 pages, 3 figures; major updat

    Bipartite S₂ graphs are Cohen-Macaulay

    Get PDF

    Water exploitation of Karoon River for fish culturing through monitoring and simulation systems

    Get PDF
    Heavy metal pollution dispersion simulation in rivers and predicting spatial and temporal variations of pollutants can be used to determine the precise place and to schedule water withdrawal time for drinking, agriculture, aquaculture and ecosystem studies. To study the movement of heavy metal pollution through Karoon flow model, MIKE 11 was employed for simulation of the flow model of Karoon River as well as heavy metal moving. The model was run for lead along the 214 km of Karoon River from Ahwaz to Darkhvein. The input data used for this model were river morphology parameters, statistical data of water flow and water contamination. The output of the model conformed to real data collected from different locations along the River. It was concluded that Karoon River water exploitation for fish culturing (e.g., salmon culture) should be at least 40 km far from Ahwaz (close to Bayoz City) from July to December and 20 km for the rest of the year

    Formation and Growth of the First Supermassive Black Holes in MOG

    Full text link
    The emergence of supermassive black holes (SMBHs) in the early universe remains a topic of profound interest and debate. In this paper, we investigate the formation and growth of the first SMBHs within the framework of Modified Gravity (MOG), where gravity exhibits increased strength. We explore how MOG, as an alternative to the standard model, may offer novel insights into the emergence of SMBHs and potentially reconcile the discrepancies observed in the accretion and growth processes. We examine the dynamics of gas and matter in this modified gravitational framework, shedding light on the unique interplay between gravity and the formation of SMBHs

    Parameters Affecting Genetic Algorithm In Leak Detection By Inverse Transients Analysis

    Get PDF
    Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

    The lethal concentration (LC50) of Zataria multiflora essential oil in fries of rainbow trout (Oncorhynchus mykiss)

    Get PDF
    This research was carried out to determine LC50 for Zataria multiflora essential oil in rainbow trout (Oncorhynchus mykiss) fries at 96 hours. In the process, we used the static O.E.C.D method for 180 rainbow trout fries weighing 5±1 grams in five treatments and one control with three replicates. During the experiments, the mean (±SD) of water temperature was kept at 16±1 C, dissolved oxygen (DO) was 7±0.2mg/l and pH was 8±0.4. We used 5- 25ppm of the essential oil and the results were analyzed using probit analysis procedure. The LC50 96h of Zataria multiflora essential oil was determined as 13.6ppm for rainbow trout (Oncorhynchus mykiss) fry. Based on the results, the useful maximum concentration of Zataria multiflora essential oil was less than 10ppm in rainbow trout fry. The results indicated a narrow therapeutic index for Zataria multiflore essential oil

    Investigation of survival ratio and growth rate in offspring of Salmo trutta caspius

    Get PDF
    We investigated the survival ratio and the growth rate of offspring of Salmo tuna caspius produced from three groups of brood fish in Shahid Bahonar Rearing and Breeding Center in Klardasht in 2005. The three groups of brood fish belonged the early, mid, and late-migration period. The sampling was done randomly, and in each group 15 female and 5 male fish were included. After spawning and hatching, 22500 eggs were used in each group (3 treatments, repeated 9 times). The results showed no significant difference in the survival ratio of the egg and larva in the three groups of the brood fish in each stage of evolution up to two months after the start of active feeding (P>0.05). However, after the start of active feeding there was a significant difference (P 0.05). Based on the results, we suggest that the brood fish from the early migration period are more suitable for producing offspring and their offspring pass through the smoltification stage more rapidly. However, in terms of genetic diversity, it would be appropriate to use brood fish from all migration periods

    Inkjet-printed vertically emitting solid-state organic lasers

    Full text link
    In this paper, we show that Inkjet Printing can be successfully applied to external-cavity vertically-emitting thin-film organic lasers, and can be used to generate a diffraction-limited output beam with an output energy as high as 33.6 uJ with a slope efficiency S of 34%. Laser emission shows to be continuously tunable from 570 to 670 nm using an intracavity polymer-based Fabry-Perot etalon. High-optical quality films with several um thicknesses are realized thanks to ink-jet printing. We introduce a new optical material where EMD6415 commercial ink constitutes the optical host matrix and exhibits a refractive index of 1.5 and an absorption coefficient of 0.66 cm-1 at 550-680 nm. Standard laser dyes like Pyromethene 597 and Rhodamine 640 are incorporated in solution to the EMD6415 ink. Such large size " printed pixels " of 50 mm 2 present uniform and flat surfaces, with roughness measured as low as 1.5 nm in different locations of a 50um x 50um AFM scan. Finally, as the gain capsules fabricated by Inkjet printing are simple and do not incorporate any tuning or cavity element, they are simple to make, have a negligible fabrication cost and can be used as fully disposable items. This works opens the way towards the fabrication of really low-cost tunable visible lasers with an affordable technology that has the potential to be widely disseminated
    corecore