ABSTRACT
Unavoidable flaring in downstream oil industry causes pollutant emission in large amounts which is potentially harmful to nearby cities or farms. Hence one must manage exhaust toxic gases to raise enough in atmosphere or redirect from such places. Since Kirkuk refinery in north Iraq is next-door to agricultural farms on west yet to residential areas on east optimizing its layout for flare stacks is something acute. In this work we wrote codes in MATLAB software to simulate incomplete rather than complete oxidation as well as pollutant generation reactions. Then we made use of FLEUENT software to simulate pollutant propagation in Kirkuk oil purifier complex yet also farther to city as well as farms with respect to seasonal air currents on lowest troposphere layer. Finally, we set neural network approach to train on simulation data thereafter to unify outcomes to turn into a fast technique for layout optimization. Results show that optimization process efficiency relies on air current velocities as well as its direction. At intermediate air flow rates optimum layout includes only a selective portion of existent flare stacks. Outcomes also illustrate that heuristic techniques that have stronger local search such as particle swarm or artificial immune system can improve flare layout in seasons with intermediate air currents here summer plus early months in autumn while approaches with weak local search like Monte Carlo are more appropriate in winter for which we have no or low air flows in Kirkuk governorate.
ABSTRACT
We studied the mechanical properties and wear performance of AISI 1045 (Ck45) carbon steel under the influence of pulsed plasma nitriding. The treatments were performed at temperatures of 500 and 550 degrees C in N2:H2 gas ratios of 1:3 and 3:1 and the working pressure of 10 mbar for 1 to 4 hours. Samples were examined by X-ray diffraction, optical, electron and atomic force microscopy, microhardness tests, roughness measurements and wear tests. Nitride layers were mainly composed of epsilon-(Fe2-3N) or gamma'-(Fe4N) depending on the gas ratio and/or temperature and time. When the nitriding time is increased, the composition of the compound layer varies from monophase gamma'-(Fe4N) to the two phase of epsilon-(Fe2-3N) and gamma'-(Fe4N). The highest thickness and hardness of the layers were obtained at 550 degrees C in the N2:H2 gas ratios of 3:1 for 4 h. The topographical evolution and surface roughness of the samples showed that all the roughness parameters increase with increasing the temperature. The friction coefficient of all samples was higher than that of untreated material. Wear performance of all nitrided samples was significantly better than that of untreated material.
ABSTRACT
An on-line, real-time menu management system was developed as a module of the integrated computer-assisted food management system implemented at the University of Missouri-Columbia Health Sciences Center Department of Nutrition and Dietetics. This system supplants a former automated form generating system and permits flexibility in menu design. The major data base in the system is the Master Menu File, which is updated using real-time processing. This file contains data about each occurrence of menu items and is interfaced with existing recipe files to produce numerous printed documents and to display the menu on a video display terminal. The major benefits of the system are flexibility and elimination of typing of worksheets. Entering a new menu or changes to the menu require only a brief amount of time; new revised documents relative to the menu can be generated on the same day. Some of the types of documents available from this system are: master menu, nutrient syllabi, menu audit, and food production forms. The menu is available on-line at all times for reference by dietitians and supervisors. The Master Menu File will be utilized more fully as new modules are designed to interface with the Menu Management System. Production forecasting, patient menu printing, and individualized diet planning are three potential enhancements to the system which will utilize data in the Master Menu File. The file was designed to accommodate additional data as the system in further matured.
