Flux declines versus time during cross‐flow microfiltration of wheat starch suspensions were modeled using fuzzy logic systems under different conditions of transmembrane pressure, flow rate, and ...suspension concentration. Fuzzy modeling is one of the most efficient methods for empirical modeling, especially for non‐linear systems, and does not require any prior knowledge about the process. The influence of the process parameters on the dynamic behavior of the permeate flux was determined by comparing the permeate flux decline versus the volume curves, considering a constant value of the volumetric concentration factor during batch cross‐flow filtration. At the transient stages of the filtration process, the permeate flux was shown to be strongly dependent on all process parameters, within the examined range.
The ability of the fuzzy controller to predict the decline in permeate flux during starch suspension microfiltration, under different operational conditions with respect to time, was studied. Since the operating conditions significantly affected the transient flux behavior, the influence of the transmembrane pressure, the flow rate, and the suspension concentration was discussed.
The aim of this study was to determine the cadmium concentration in four muscles and 10 edible offal items of 15 free-range reared Swallow-belly Mangulica pigs from Vojvodina, by flame atomic ...absorption spectrometry after mineralisation by dry ashing. All individual concentrations in muscles and heart, tongue, spinal cord, back fat and leaf fat were below the limit of detection (LOD = 0.050 mg/kg). In lungs, spleen and brain, cadmium concentrations ranked from below LOD, 0.055 and 0.058 to 0.057, 0.065 and 0.074 mg/kg, respectively. The concentration of cadmium in liver and kidney ranged from 0.089 to 0.116 mg/kg and from 0.204 to 0.440 mg/kg, respectively. Cadmium concentrations in liver and kidney of free-range reared Swallow-belly Mangulica pigs slaughtered at about 20 months of age were lower than in liver and kidney of commercial pigs from Vojvodina, slaughtered at about 6 months of age.
For decades manganese steel casts have been most used materials for manufacturing elements subjected to impact and high stress abrasion. These materials are used in countless industrial applications ...that involve crushing of raw material by impact. Some of most important characteristics of manganese cast steels are work-hardening and high strength. Opposite from manganese steels, highly alloyed white cast irons are materials with high amount of hard carbide phases that shows better abrasion resistance but have lower strength and impact energy. Aim of this paper is to investigate possibilities to reduce costs and maintenance periods by implementing bimetallic materials.
This paper presents machining parameters (turning process) optimization based on the use of artificial intelligence. To obtain greater efficiency and productivity of the machine tool, optimal cutting ...parameters have to be obtained. In order to find optimal cutting parameters, the genetic algorithm (GA) has been used as an optimal solution finder. Optimization has to yield minimum machining time and minimum production cost, while considering technological and material constrains.
Effects of rapid chilling of carcasses (at −31°C in the first 3h of chilling, and then at 2–4°C) and earlier deboning (8h post-mortem), compared to rapid (till 24h post-mortem) and conventional ...chilling (at 2–4°C, till 24h post-mortem), on quality characteristics of pork M. semimebranosus and cooked ham were investigated. Quality measurements included pH value, colour (CIEL*a*b* values) and total aerobic count of M. semimebranosus, as well as sensory (colour, juiciness, texture, and flavour), physical (pH value, colour – CIEL*a*b* values and texture – Warner–Bratzler shear and penetration forces) and chemical (protein, total fat, and moisture content) characteristics of cooked ham. The cooked ham was manufactured from pieces of M. semimebranosus with ultimate lightness (CIEL* value) lower than 50. Rapid chilling and earlier deboning significantly increased quantity of M. semimebranosus desirable for cooked ham manufacturing. Earlier start of pork fabrication did not affect important quality characteristics of cooked ham.
► We examine the possibility of earlier start of pork fabrication. ► Shorter chilling increased quantity of pork desirable for cooked ham manufacturing. ► Cooked ham from rapid chilled and earlier deboned pork had high quality.
Die casting process uses high productive level machines. Machine capacity utilization is a key goal in achieving minimum time consumption. Changeover procedure during die casting process is ...recognized as possible area for reducing time consumption. The SMED method has been improved by additional procedures simultaneously applying the 5S method. Their contribution is evident in recognition of internal and external activities, particularly while transferring internal activities into external ones in as many numbers as possible, by minimizing at the same moment the internal ones. The validity of the method and procedures are verified by an example application of die casting foundry for casting automobile parts. Significant time savings have been achieved with minimum investment.
In continuous casting steel production a significant loss reduction-in terms of scrap material, time and money-can be achieved by developing an appropriate algorithm for the prevention of molten ...steel sticking onto mould. The logic of such algorithm should be simple and manageable to ensure its practical implementation on a computer system via the usage of thermo sensors. This suggests that both the algorithm and the automated data collection can be implemented by means of applicative software. Despite its simplicity, the algorithm should accurately trace physical phenomena in molten steel.
The purpose of presented research was to develop feasible model for leadership competence management in metallurgical companies. Results of the research are presented in the form of a structured ...procedure for leadership competence development and performance review. Analysis of entry requirements for employment in metallurgical companies synthesized presented set of leadership competences and matrix for calculation of leadership success was developed. With usage of these two tools it is possible to quantify the leadership performance which represents great advantage in leadership benchmarking process. During the research additional set of problems was defined. These problems were addressed heuristically in the framework of this research.
The goal of the paper is to present an outline of different modeling approach at determining of backward extrusion force on AlCu5PbBi material and to compare them with experimental obtained results. ...Stochastic modeling in the paper is based on the statistic processing of central composite experimental design i.e. in this investigations central composite circumscribed (CCC) design. The numerical modeling is based on the finite element method (FEM) using ABAQUS 6.4.1. Explicit software.
Effects of endpoint temperatures of 51, 61, 71, 81 and 91C on mineral contents (mg/100 g WW, wet weight) of pork loin (longissimus thoracis et lumborum, n = 12) were investigated. Pork was cooked in ...water bath set to 100C. In both raw and cooked samples, phosphorus was determined by the standard spectrophotometric method while metals (potassium, sodium, magnesium, calcium, zinc, iron, copper and manganese) were determined by the flame atomic absorption spectrometry after mineralization by dry ashing. All cooking treatments led to significantly increased mineral contents, except for potassium and sodium, compared to raw meat. As endpoint temperature was increased, mineral contents increased, reaching numerically or significantly highest contents at: 61C for sodium and magnesium; 71C for phosphorus, potassium, calcium, zinc, copper and manganese; and 81C for iron, after which mineral contents decreased.
Practical Applications
During cooking, the meat undergoes changes in its physical properties and chemical composition. Cooking temperature and especially endpoint internal temperature affect mineral contents of cooked pork. Thus, it is important to know the extent of mineral losses occurring during different boiling treatments. Data in the most food composition tables are based on mineral contents of raw meat. The results provide update and improve regularly nutrient compositional data of meat.