86,529 research outputs found
Hybrid meta-heuristic algorithms for optimising a sustainable agricultural supply chain network considering CO2 emissions and water consumption
No full textIn this research, a new mixed-integer linear programming (MILP) formulation for the production-distribution-routing problem is developed in a sustainable agricultural product supply chain network (SAPSCN) considering CO2 emission. The objective functions of the SAPSCN model seek to minimise the economic effects containing total cost in SAPSCN and environmental impacts including production and operation emissions, water consumption in production, operational water consumption, and transportation emission, as well as to maximise social impacts including on the number of the created works. Due to the complexity and NP-hardness of the SAPSCN formulation, four multi-objective meta-heuristic algorithms were applied, and two new hybrid meta-heuristic algorithms were developed. To assess the efficiency of the suggested meta-heuristic algorithms, various test instances were used to solve the proposed model and comparisons and sensitivity analyses were carried out with various criteria. A real case study is provided to validate the mathematical model. Finally, the results of the hybrid simulated annealing and particle swarm optimisation algorithm emphasises that it is more robust than other proposed algorithms to solve the problem in a reasonable time
Designing a new mathematical model based on ABC analysis for inventory control problem: A real case study
No full textIn modern business today, organizations that hold large numbers of inventory items, do not find it economical to make policies for the management of individual inventory items. Managers, thus, need to classify these items according to their importance and fit each item to a certain asset class. The method of grouping and inventory control available in traditional ABC has several disadvantages. These shortcomings have led to the development of an optimization model in the present study to improve the grouping and inventory control decisions in ABC. Moreover, it simultaneously optimizes the existing business relationships among revenue, investment in inventory and customer satisfaction (through service levels) as well as a company's budget for inventory costs. In this paper, a mathematical model is presented to classify inventory items, taking into account significant profit and cost reduction indices. The model has an objective function to maximize the net profit of items in stock. Limitations such as budget even inventory shortages are taken into account too. The mathematical model is solved by the Benders decomposition and the Lagrange relaxation algorithms. Then, the results of the two solutions are compared. The TOPSIS technique and statistical tests are used to evaluate and compare the proposed solutions with one another and to choose the best one. Subsequently, several sensitivity analyses are performed on the model, which helps inventory control managers determine the effect of inventory management costs on optimal decision making and item grouping. Finally, according to the results of evaluating the efficiency of the proposed model and the solution method, a real-world case study is conducted on the ceramic tile industry. Based on the proposed approach, several managerial perspectives are gained on optimal inventory grouping and item control strategies
Supply chain network design based on Big Data Analytics: heuristic-simulation method in a pharmaceutical case study
No full textDigital technology is a pivotal aspect of the ongoing digital transformation upon which supply chain
networks (SCNs) heavily rely. Through the utilization of Big Data Analytics (BDA), organizations can
gain insights into sales, production and formulate decision support systems. The pharmaceutical supply
chain emerges as a crucial player in producing and distributing medications vital for treating
COVID-19 patients. In this study, we have innovatively designed a multi-echelon Pharmaceutical
Supply Chain Network (PSCN) using BDA during the COVID-19 pandemic. We have developed a novel
Mixed-Integer Non-Linear Programming model addressing allocation, production planning, and inventory
control decisions, known as the LAPI problem. A transformation method is employed to convert
the non-linear model into a linear one to enhance computational efficiency. The primary objective of
our mathematical model is to minimize the total cost and CO2 emissions of the transportation system
and established centres while maximizing the shelf life of medicines. Our experiments reveal that
medium- and large-scale problems, characterized by the three main attributes of BDA – variety, velocity
and volume (3 V‟s), pose challenges for optimal solutions. We present a case study of Iran to validate
the mathematical model for large-scale problems. Employing a simulation approach, we estimate
the demand for required pharmaceuticals, underscoring our proposed model’s real-world applicability
and effectiveness. This research contributes to the growing necessity of eco-friendly and efficient supply
chain strategies, especially in the critical domain of pharmaceuticals during pandemic situations
Variations on the Author
No full text“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
[Newspaper Clipping: Author Claims Evidence of Second JFK Assassin #1]
No full textNewspaper article titled "Author Claims Evidence of Second JFK Assassin." The article states that author Richard J. Whalen concluded "that there is circumstantial evidence to support the theory of a second assassin in the shooting of President John F. Kennedy.
A Rigorous Method for Special Core Analysis SCAL Data Correction in the Presence of Capillary End Effects
No full textOne way of obtaining water-oil relative permeability curves is from co-injection (of water and oil)experiments at steady-state (SS) condition. The two-phase Darcy Law can be used to calculate the relativepermeability directly only when water saturation is constant along the core. However, the capillary endeffect (CEE) causes water accumulation or depletion at the end of the core depending upon the wettability.This work describes an improved method for correcting for this effect by modifying the "intercept method"initially proposed by Gupta and Maloney (2014). Similar to their work, we again envisage carrying out a steady-state co-injection experiment. For eachratio of water to oil flowrate (), we require experiments at several different total flowrates to becarried out. From each run, we obtain pressure drop across the core and average water saturation insidethe core. We demonstrate mathematically that a plot of pressure difference vs. oil flowrate yields a straight linewhose slope gives the oil relative permeability which can be used to calculate water relative permeability.A plot of average water saturation vs. reciprocal of oil flowrate gives a straight line whose intercept is thewater saturation associated with the oil/water relative permeability values just obtained. It is necessary toperform the same experiment for at least two values of water and oil flowrates while the ratio is constantsince we require at least two points to construct a straight line. The same procedure is used for other valuesof F to obtain more data points to construct the relative permeability curves. We have also mathematicallycorrected Gupta and Maloney-s work and other works after them and arrived at a simpler and more rigorousmethod. The details of how our method builds upon and improves their work will be published in due course(Goodarzian and Sorbie, 2020).</p
Also By The Same Author: AKTiveAuthor, a Citation Graph Approach to Name Disambiguation
No full textThe desire for definitive data and the semantic web drive for inference over heterogeneous data sources requires co-reference resolution to be performed on those data. In particular, name disambiguation is required to allow accurate publication lists, citation counts and impact measures to be determined. This paper describes a graph-based approach to author disambiguation on large-scale citation networks. Using self-citation, co-authorship and document source analyses, AKTiveAuthor clusters papers, achieving precision of 0.997 and recall of 0.818 over a test group of eight surname clusters
John F. Kennedy telegram to Roosevelt
No full textJersey Homesteads (later the Borough of Roosevelt) was established in the 1930s as an agro-industrial cooperative community. It was established specifically for urban Jewish garment workers, many of whom had emigrated from Europe. President John F. Kennedy sent a telegram to the citizens of Roosevelt, New Jersey, apologizing for not being able to attend the memorial dedication in honor of former President Franklin Delano Roosevelt. (Jersey Homesteads became Roosevelt in 1945 in honor of the president.) President Kennedy expressed his gratitude to the people of Roosevelt for constructing the memorial, and commented that it will serve as a constant reminder of Roosevelt's good works
Logarithmic variance profiles and the corresponding f-1 spectra of temperature fluctuations in turbulent Rayleigh-Bénard convection
No full textWe report experimental results for the temperature variance 2(z) and the corresponding frequency spectra P(f) in turbulent Rayleigh-Bénard convection (RBC) in a cylindrical sample of aspect ratioT= D/L = 1:00 (D = 1:12 m is the diameter and L = 1:12 m the height). The measurements were conducted in the Rayleigh-number range 1011 < Ra < 1:35 1014 and Pr ' 0:8. For Ra = 1:35x1014, 2(z) could be described well by a logarithmic dependence on the vertical position z in a range of z 1 < z < z 2 with z 1 ' 70 and z 2 = 0:1L. Here L=(2Nu) is the thickness of a thin thermal sublayer adjacent to the horizontal plate where the heat flux (denoted by the Nusselt number Nu) is carried mostly by thermal diffusion. In the log layer, we found that the temperature spectra had a significant frequency range over which P(f) f with close to 1. As Ra decreased, increased so that the log layer became thinner. At Ra = 2:05 1011, z 2 < z 1 and therefore there was no range for a log layer. Correspondingly, the temperature spectrum near the horizontal plate did not have the f1 scaling form either
Maine author Franklin F. Gould recalls his first glimpse of the outside world
No full textMaine author Franklin F. Gould recalls his first glimpse of the outside world as he relates how, as a young farm boy in the late 1800\u27s, he drove his father\u27s horses on an errand to an icebound river
- …
