Dynamic Resource Allocation in Disaster Response: Tradeoffs in Wildfire Suppression

Challenges associated with the allocation of limited resources to mitigate the impact of natural disasters inspire fundamentally new theoretical questions for dynamic decision making in coupled human and natural systems. Wildfires are one of several types of disaster phenomena, including oil spills and disease epidemics, where (1) the disaster evolves on the same timescale as the response effort, and (2) delays in response can lead to increased disaster severity and thus greater demand for resources. We introduce a minimal stochastic process to represent wildfire progression that nonetheless accurately captures the heavy tailed statistical distribution of fire sizes observed in nature. We then couple this model for fire spread to a series of response models that isolate fundamental tradeoffs both in the strength and timing of response and also in division of limited resources across multiple competing suppression efforts. Using this framework, we compute optimal strategies for decision making scenarios that arise in fire response policy

Biomasa iz poljoprivrede kao potencijani izvor alternativnih goriva pogonskih agregata

Liquid fossil fuels are the dominant fuel for the plant, as means of all forms of transport, employment and agricultural machines and aggregates. In the coming period is unrealistic to expect more intense and massive development, implementation, construction of new engines that would be adapted to another type of fuel. All efforts have been focused on finding such a fuel that could be adapted to existing engine structures, and to simultaneously satisfy additional criteria related to ecology, as well as reliability and privacy. In this context, biofuel is given increasing attention, which can be produced from renewable primary and secondary agricultural raw materials, with generally positive effects of performance, reliability, emissions and thus protect the environment, as well as other requirements that the current fossil fuel backgrounds meet. As biofuels can be considered methanol, biometanol, bioethanol, biodiesel, natural gas, hydrogen and others. Raw materials from agricultural biomass to produce alternative fuels could be: sugar cane, sugar beet, corn sorghum, corn, wheat, rapeseed, sunflower, potatoes, barley, olive, palm, sweet potato, monioka, Jerusalem artichokes (topinambur) and others. Products and residues from forest mass: wood, pulp, paper, black lug and others. Now it different kinds of waste such as municipal and secondary waste, food wastes, wastes from production of cereals and food, etc.., With the current use of fossil origin fuel from oil, coal, oil shale, natural gas and others. The paper gives a brief review of possible fuel from biomass, which can be, with its advantages and disadvantages, potential use as fuel internal combustion engines.Tečna fosilna goriva su najdominantnija goriva za pogon, kako sredstava svih vidova saobraćaja, tako i poljoprivrednih radnih mašina i agregata. U narednom periodu je nerealno očekivati intenzivniji i masovniji razvoj, u primeni, novih konstrukcija motora koje bi bile prilagođene nekoj drugoj vrsti goriva. Svi napori su usredsređeni na pronalaženju supstitucije goriva, koje bi bilo prilagođeno postojećim konstrukcijama motora, a da istovremeno zadovolje i dodatne kriterijume vezane za obnovljivost, ekologiju, pouzdanost korišćenja i dr. U tom kontekstu, biogorivima se posvećuje sve veća pažnja, koja se mogu proizvesti iz obnovljivih primarnih i sekundarnih poljoprivrednih sirovina, sa generalno pozitivnim efektima performansi, pouzdanosti, emisije izduvnih gasova, a time i zaštite životne sredine, kao i drugim zahtevima koje sadašnja goriva fosilnog porekla ispunjavaju. Kao biogoriva mogu se razmatrati metanol, biometanol, bioetanol, biodizel, prirodni gas, vodonik i dr. Sirovine iz poljoprivredne biomase za proizvodnju alternativnih goriva mogu biti: šećerna trska, šećerna repa, sirak šećerac, kukuruz, pšenica, uljana repica, suncokret, krompir, ječam, maslina, palma, batata, monioka, jerusalemska artičoka (topinambur) i dr. Iz proizvoda i ostataka šumskih masa: drvo, celuloza, papir, crni lug i dr. Zatim iz različitih vidova otpada, kao što su: komunalni i sekundarni otpad, otpadi iz proizvodnje žitarica i hrane i dr., uz sadašnju primenu goriva fosilnog porekla iz: nafte, uglja, uljnih škriljaca, prirodnog gasa i dr. U radu je dat kraći prikaz mogućih vrsta goriva iz biomase, koja se mogu, sa svojim prednostima i manama, potencijalno koristiti kao pogonsko gorivo motora SUS

Uticaj potencijalnih vučnih karakteristika traktora Fendt u optimizaciji obrade zemljišta

Trend development of agricultural tractors, follows agrotechnique and to the general development of technique, that fundamental investigations find their full application in the world manufacturing of tractors also. This paper analyses the potential performance of a tractor Fendt production and their impact on the optimization of agricultural conditions in the processing of agricultural land in Serbia. Fendt tractors manufacturing have all the characteristics of contemporary world of tractors based on the basis of increasing engine power while keeping intact mass of the tractor in the individual series. Comprehensive analysis of Fendt tractors is made of several approaches, the three series of tractors from 700, 800 and 900, and one of these results is shown in this paper. Based on the analysis it can be concluded that the particular batch of tractors complement each other in relation to the demands of agricultural technology and farm size, which provide optimum conditions for processing various types of soil in accordance with the requirements of modern production agriculture. Such an approach to the analysis of potential impact on the optimization of processing characteristics of the soil, allows potential buyers relief decision to buy the tractor, depending on their requirements.Trend razvoja poljoprivrednih traktora prati agrotehnički i opšti razvoj tehnike, tako da fundamentalna istraživanja nalaze punu primenu i u svetskoj proizvodnji traktora. U radu su analizirane potencijalne eksploatacione karakteristike traktora proizvodnje Fendt i njihov uticaj na optimizaciju agrotehničkih uslova u obradi poljoprivrednog zemljišta Srbije. Traktori proizvodnje Fendt imaju sve karakteristike savremenih svetskih traktora koje se zasnivaju na bazi povećanja snage motora uz zadržavanje nepromenjene mase traktora u okviru pojedinih serija. Sveobuhvatna analiza traktora Fendt je izvršena od više raspoloživih modela, na tri traktora iz serija 700, 800 i 900, a jedan deo tih rezultata, prikazan je u ovom radu. Na osnovu izvršene analize nameće se zaključak, da se pojedine serije traktora međusobno dopunjuju u odnosu na zahteve agrotehnike i veličinu poseda, čime se obezbeđuju uslovi za optimalnu obradu različitih tipova zemljišta u skladu sa zahtevima proizvodnje savremene poljoprivrede. Takav pristup analizi uticaja potencijalnih karakteristika na optimizaciju obrade zemljišta, omogućava potencijalnim kupcima olakšanje odluke o kupovini traktora u zavisnosti od njihovih zahteva

The Star Formation History of Galaxies Measured from Individual Pixels. I. The Hubble Deep Field North

We analyze the photometric information contained in individual pixels of galaxies in the Hubble Deep Field North (HDFN) using a new technique, _pixel-z_, that combines predictions of evolutionary synthesis models with photometric redshift template fitting. Each spectral energy distribution template is a result of modeling of the detailed physical processes affecting gas properties and star formation efficiency. The criteria chosen to generate the SED templates is that of sampling a wide range of physical characteristics such as age, star formation rate, obscuration and metallicity. A key feature of our method is the sophisticated use of error analysis to generate error maps that define the reliability of the template fitting on pixel scales and allow for the separation of the interplay among dust, metallicity and star formation histories. This technique offers a number of advantages over traditional integrated color studies. As a first application, we derive the star formation and metallicity histories of galaxies in the HDFN. Our results show that the comoving density of star formation rate, determined from the UV luminosity density of sources in the HDFN, increases monotonically with redshift out to at least redshift of 5. This behavior can plausibly be explained by a smooth increase of the UV luminosity density with redshift coupled with an increase in the number of star forming regions as a function of redshift. We also find that the information contained in individual pixels in a galaxy can be linked to its morphological history. Finally, we derive the metal enrichment rate history of the universe and find it in good agreement with predictions based on the evolving HI content of Lyman-alpha QSO absorption line systems.Comment: Accepted for publication in the Astronomical Journal. Full resolution figures available at http://www.stsci.edu/~aconti/pixelz.htm

Systematic Effects of Foreground Removal in 21cm Surveys of Reionization

It is well-known that foreground subtraction in 21cm surveys removes large scale power. We investigate associated systematic biases. We show that removing line-of-sight fluctuations on large scales aliases into suppression of the 3D power spectrum across a broad range of scales. This bias can be eliminated by marginalizing over small k in the 1D power spectrum; however, the unbiased estimator will have unavoidably larger variance. We also show that Gaussian realizations of the power spectrum permit accurate and extremely rapid Monte-Carlo simulations for error analysis; repeated realizations of the fully non-Gaussian field are unnecessary. We perform Monte-Carlo maximum-likelihood simulations of foreground removal which yield unbiased, minimum variance estimates of the power spectrum in agreement with Fisher matrix estimates. Foreground removal also distorts the 21cm PDF, reducing the contrast between neutral and ionized regions. We show that it is the subtraction of large-scales modes which is responsible for this distortion, and that it is less severe in the earlier stages of reionization. It can be reduced by using larger bandwidths for foreground removal. In the late stages of reionization, the largest ionized regions (which consist of foreground emission only) provides calibration points which potentially allow recovery of large-scale modes. Finally, we also show that: (i) the broad frequency response of synchrotron and free-free emission will smear out any features in the electron momentum distribution and ensure spectrally smooth foregrounds; (ii) extragalactic radio recombination lines should be negligible foregrounds.Comment: Minor editorial changes (including title) to match published version; conclusions unchanged. 20 pages, 18 figure

The effect of Galactic foreground subtraction on redshifted 21-cm observations of quasar HII regions

We assess the impact of Galactic synchrotron foreground removal on the observation of high-redshift quasar HII regions in redshifted 21-cm emission. We consider the case where a quasar is observed in an intergalactic medium (IGM) whose ionisation structure evolves slowly relative to the light crossing time of the HII region, as well as the case where the evolution is rapid. The latter case is expected towards the end of the reionisation era where the highest redshift luminous quasars will be observed. In the absence of foregrounds the fraction of neutral hydrogen in the IGM could be measured directly from the contrast between the HII region and surrounding IGM. However, we find that foreground removal lowers the observed contrast between the HII region and the IGM. This indicates that measurement of the neutral fraction would require modelling to correct for this systematic effect. On the other hand, foreground removal does not modify the most prominent features of the 21-cm maps. Using a simple algorithm we demonstrate that measurements of the size and shape of observed HII regions will not be affected by continuum foreground removal. Moreover, measurements of these quantities will not be adversely affected by the presence of a rapidly evolving IGM.Comment: 9 pages, 3 figure

INTEGRATION OF COMPLEMENTARY BIOMARKERS IN PATIENTS WITH FIRST EPISODE PSYCHOSIS: RESEARCH PROTOCOL OF A PROSPECTIVE FOLLOW UP STUDY

In this project, we recruited a sample of 150 patients with first episode of psychosis with schizophrenia features (FEP) and 100 healthy controls. We assessed the differences between these two groups, as well as the changes between the acute phase of illness and subsequent remission among patients over 18-month longitudinal follow-up. The assessments were divided into four work packages (WP): WP1- psychopathological status, neurocognitive functioning and emotional recognition; WP2- stress response measured by saliva cortisol during a stress paradigm; cerebral blood perfusion in the resting state (with single photon emission computed tomography (SPECT) and during activation paradigm (with Transcranial Ultrasonography Doppler (TCD); WP3-post mortem analysis in histologically prepared human cortical tissue of post mortem samples of subjects with schizophrenia in the region that synaptic alteration was suggested by WP1 and WP2; WP4- pharmacogenetic analysis (single gene polymorphisms and genome wide association study (GWAS). We expect that the analysis of these data will identify a set of markers that differentiate healthy controls from patients with FEP, and serve as an additional diagnostic tool in the first episode of psychosis, and prediction tool which can be then used to help tailoring individualized treatment options. In this paper, we describe the project protocol including aims and methods and provide a brief description of planned post mortem studies and pharmacogenetic analysis

Obtaining of the antioxidants by supercritical fluid extraction

One of the important trends in the food industry today is demand for natural antioxidants from plant material. Synthetic antioxidants such as butylated hydroxytoluene (BHT), and butylated hydroxyanisole (BHA) are now being replaced by the natural antioxidants because of theirs possible toxicity and as they may act as promoters of carcinogens. The natural antioxidants may show equivalent or higher antioxidant activity than the endogenous or the synthetic antioxidants. Thus, great effort is being devoted to the search for alternative and cheap sources of natural antioxidants, as well as to the development of efficient and selective extraction techniques. The supercritical fluid extraction (SFE) with carbon dioxide is considered to be the most suitable method for producing natural antioxidants for the use in food industry. The supercritical extract does not contain residual organic solvents as in conventional extraction processes, which makes these products suitable for use in food, cosmetic and pharmaceutical industry. The recovery of antioxidants from plant sources involves many problematic aspects: choice of an adequate source (in terms of availability, cost, difference in phenolic content with variety and season); selection of the optimal recovery procedure (in terms of yield, simplicity, industrial application, cost); chemical analysis of extracts (for optimization purposes a fast colorimetric method is more preferable than a chromatographic one); evaluation of the antioxidant power (preferably by the different assay methods). The paper presents information about different operational methods for SFE of bioactive compounds from natural sources. It also includes the various reports on the antioxidant activity of the supercritical extracts from Lamiaceae herbs, in comparison with the activity of the synthetic antioxidants and the extracts from Lamiaceae herbs obtained by the conventional methods