920 research outputs found

    Inventory Model with Ramp-type Demand and Price Discount on Back Order for Deteriorating Items under Partial Backlogging

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    Modeling of inventory problems provides a good insight to retailers and distributors to maintain stock of different items such as seasonal products, perishable goods and daily useable goods etc. The deterioration of all these items exists to a certain extent due to several reasons like mishandling, evaporation, decay, environmental conditions, transportation etc. It is found from the literature that previously many of the researchers have developed inventory model ignoring deterioration and drawn conclusion. In the absence of deterioration parameter, an inventory model cannot be completely realistic. In this paper, we have made an attempt to extend an inventory model with ramp-type demand and price discount on back order where deterioration was not taken into account. In our study, deterioration and constant holding cost are taken into consideration keeping all other parameters same. As a result, the inventory cost function is newly constructed in the presence of deterioration. The objective of this investigation is to obtain optimal cycle length, time of occurrence of shortages and corresponding inventory cost. This extended model is solved for minimum value of average inventory cost analytically. A theorem is framed to characterize the optimal solution. To validate the proposed model, a numerical example is taken and convexity of the cost function is verified. In order to study the effect of changes of different parameters of the inventory system on optimal cycle length, time of occurrence of shortages and average inventory cost, sensitivity analyses have been performed. Also, the numerical result and sensitivity analyses are graphically presented in the respective section of this paper to demonstrate the model. This study reveals that a better solution can be obtained in the presence of our newly introduced assumptions in the existing model

    Large scale synthesis of 2D graphene oxide by mechanical milling of 3D carbon nanoparticles in air

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    Graphene oxide (GO) is one of the important functional materials. Large-scale synthesis of it is very challenging. Following a simple cost-effective route, large-scale GO was produced by mechanical (ball) milling, in air, of carbon nanoparticles (CNPs) present in carbon soot in the present study. The thickness of the GO layer was seen to decrease with an increase in milling time. Ball milling provided the required energy to acquire the in-plane graphitic order in the CNPs reducing the disorders in it. As the surface area of the layered structure became more and more with the increase in milling time, more and more oxygen of air got attached to the carbon in graphene leading to the formation of GO. An increase in the time of the ball mill up to 5 hours leads to a significant increase in the content of GO. Thus ball milling can be useful to produce large-scale two-dimensional GO for a short time.Comment: 23 pages, 10 figure

    Tropical cyclone intensity prediction over the North Indian Ocean - An NWP based objective approach

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    A Numerical Weather Prediction (NWP) based objective intensity prediction approach has been explored for prediction of tropical cyclone intensity over the North Indian Ocean (NIO) using ECMWF model outputs. The intensity of a tropical cyclone is classified by the maximum sustained wind (10-min mean) according to World Meteorological Organization (WMO). An empirical relationship between the difference of the model’s maximum mean sea level pressure (MSLP) inside a 6° × 6° grid box around the centre of the system and the lowest mean sea level pressure at the centre of the system (ΔP) with the observed intensity is developed using over 100 analyses during 2010–2012. The same is used to predict intensity of very severe cyclonic storm Hudhud and a Deep Depression observed over the Bay of Bengal during 2014. The results show that the empirical equation is skillful in prediction of intensity as compared to predictions computed using the relationship (V_{max} = K sqrt(Delta P)) with different constant values of K. The error analyses show that the relative error in intensity prediction using the empirical equation derived in the present study is 34% less than the same using (K = 14.2 kt/sqrt(hPa)) in (V_{max} = K sqrt(Delta P)) with an improvement which is significant at the level of 0.95.U radu je istražena metoda objektivne prognoze intenziteta tropskih ciklona nad Sjeverno-indijskim oceanom (NIO) temeljm numeričke prognoze vremena (NWP) modelom Europskog centra za srednjoročnu prognozu vremena (ECMWF). Intenzitet tropskog ciklona klasificira se prema prema Svjetskoj meteorološkoj organizaciji (WMO) na temelju maksimalnog vjetra (10-minutni srednjak). Upotrebom preko 100 analiza tijekom 2010. – 2012. izvedena je empirijska relacija koja povezuje razliku između najvećeg srednjeg tlaka zraka na razini mora (MSLP) unutar kvadrata mreže 6° × 6° oko središta sustava i najnižeg srednjeg tlaka na razini mora u središtu sustava (Δ P) s opaženim intenzitetom ciklona. Dobivena relacija primjenjena je na prognozu intenziteta olujnih ciklona Hudhud i Deep Depression (Duboka depresija) koji su opaženi u Bengalskom zaljevu tijekom 2014. godine. Rezultati pokazuju da empirijska jednadžba prognozira intenzitet ciklona uspješnije od prognoza izračunatih pomoću relacije (V_{max} = K sqrt(Delta P)) s različitim konstantnim vrijednostima K. Analize pogrešaka pokazuju da je relativna pogreška u prognozi intenziteta primjenom dobivene empirijske jednadžbe 34% manja od pogreške pri korištenju relacije (K = 14.2 kt/sqrt(hPa)) u (V_{max} = K sqrt(Delta P)), a poboljšanje je značajno na razini signifikantnosti od 0,95

    Influence of 36 years of integrated nutrient management on soil carbon sequestration, environmental footprint and agronomic productivity of wheat under rice-wheat cropping system

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    A long-term field experiment was conducted to study the effects of different combinations of integrated nutrient management (INM) on carbon sequestration and wheat yield in a rice-wheat cropping system. The experiment consisted of 11 treatments that were replicated three times. The organic manures used in the study included farmyard manure (FYM), wheat straw (WS), and green manure (GM) with Sesbania aculeata. The results of the experiment revealed that the application of 50% of the recommended dose of fertilizers (RDF) along with 50% nitrogen (N) through FYM during rice cultivation, and RDF during wheat cultivation, led to a significant increase in soil organic carbon (SOC). Specifically, the SOC content was enhanced by 46.4% (18.29 Mg ha-1) compared to RDF in rice and wheat, resulting in a C sequestration rate of 0.22 Mg ha-1 year-1. These increases were higher in treatments that combined organic and inorganic inputs. Additionally, the application of 50% RDF and substituting 50% of the nitrogen with FYM during wheat cultivation resulted in a 24.7% increase in grain yield compared to RDF in rice and wheat. The INM treatments, showed significantly (p ≤ 0.05) higher agronomic efficiency (AE) of nitrogen (N), phosphorus (P) and potassium (K), partial factor productivity (PFP) of N, P and K, and carbon pool index (CPI) compared to the application of inorganic fertilizers at the recommended dose. Moreover, the INM treatments also exhibited lower greenhouse gas (GHG) emission intensity. Application of neither chemical fertilizers nor organic manure (T1) resulted in maximum GHG emission intensity (328.1 kg CO2 eq Mg−1 yield). Based on these findings, it can be concluded that the combined use of inorganic fertilizers and organic manures significantly increased crop yield and soil organic carbon sequestration while reducing GHG emissions in a rice-wheat cropping system in the eastern Indo-Gangetic Plains (EIGP) of India

    Understanding Environmental and Social Reasons Towards Abnormal Menstruation Cycle in Indian Women

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    The human female reproductive system is by far the most complex biological system, abnormal menstruation cycles is directly associated with type 2 diabetes and they have shown to be associated with cardiovascular disorders as well. The underlying reasons for abnormal menstruation cycle in Indian women is just not stress, birth control pills and or disease symptoms but signs of social and environmental factors are clearly evident now in form or traditional societal practices. This paper aims to understand the abnormal behavior of the menstruation cycle in Indian women

    Dynamics of Hot QCD Matter -- Current Status and Developments

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    The discovery and characterization of hot and dense QCD matter, known as Quark Gluon Plasma (QGP), remains the most international collaborative effort and synergy between theorists and experimentalists in modern nuclear physics to date. The experimentalists around the world not only collect an unprecedented amount of data in heavy-ion collisions, at Relativistic Heavy Ion Collider (RHIC), at Brookhaven National Laboratory (BNL) in New York, USA, and the Large Hadron Collider (LHC), at CERN in Geneva, Switzerland but also analyze these data to unravel the mystery of this new phase of matter that filled a few microseconds old universe, just after the Big Bang. In the meantime, advancements in theoretical works and computing capability extend our wisdom about the hot-dense QCD matter and its dynamics through mathematical equations. The exchange of ideas between experimentalists and theoreticians is crucial for the progress of our knowledge. The motivation of this first conference named "HOT QCD Matter 2022" is to bring the community together to have a discourse on this topic. In this article, there are 36 sections discussing various topics in the field of relativistic heavy-ion collisions and related phenomena that cover a snapshot of the current experimental observations and theoretical progress. This article begins with the theoretical overview of relativistic spin-hydrodynamics in the presence of the external magnetic field, followed by the Lattice QCD results on heavy quarks in QGP, and finally, it ends with an overview of experiment results.Comment: Compilation of the contributions (148 pages) as presented in the `Hot QCD Matter 2022 conference', held from May 12 to 14, 2022, jointly organized by IIT Goa & Goa University, Goa, Indi

    The Forward Physics Facility at the High-Luminosity LHC

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    Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC

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    Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe
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