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1.
Three interesterified vegetable oils (IVOs) prepared from palm, cottonseed, and olive oil, respectively, have been studied for application to Frankfurters. Beef fat (10%) was replaced by one of the IVOs at 20, 60 or 100%. Fatty acid composition of the lipid fraction in the Frankfurters and saturated/unsaturated ratios were established for all batches. We found that total or partial replacement of beef fat by IVOs did not lead to significant changes in appearance, colour, texture, flavour or sensory score. We conclude that IVOs may be successfully applied as beef fat substitutes in Frankfurters.  相似文献   
2.

Today, the design of antenna arrays is very important in providing effective and efficient wireless communication. The purpose of antenna array synthesis is to obtain a radiation pattern with a low side lobe level (SLL) at a desired half power beam width in far-field. The amplitude and position values of the array elements can be optimized to obtain a radiation pattern with suppressed SLLs. In this paper, swarm-based metaheuristic algorithms including particle swarm optimization (PSO), artificial bee colony (ABC), mayfly algorithm (MA) and jellyfish search (JS) are compared to determine the optimal design of linear antenna arrays. Extensive experiments are conducted on designing 10-, 16-, 24- and 32-element linear arrays by determining the amplitude and positions. Experiments are repeated 30 times due to the random nature of swarm-based optimizers, and statistical results show that the performance of the novel algorithms, MA and JS, is better than that of the well-known PSO and ABC methods.

  相似文献   
3.
Set point tracking control of autonomous underwater vehicle (AUV) via robust model predictive control (RMPC) is considered. Input-constrained RMPC with integral action, which has been developed in our previous work, is used to control the AUV in this study. In order to derive a RMPC control rule, non-linear dynamics of AUV with six degree of freedom is linearized at certain operating points. So, horizontal and vertical plane dynamics of system are represented by linear models which have polytopic uncertainties. Since the derived control rule will be used in real time, the computation time should be reduced. To overcome this computational time problem and get rid of trial–error step of Algorithm 1, a new algorithm is proposed here. The simulations are carried out using the control rule based on this algorithm and these results are presented.  相似文献   
4.
Degradation of 4-chloro-2-methylphenol (PCOC), a refractory toxic chemical emitted to the environment from the industrial production of phenoxy herbicides was studied in aqueous solution. Electro-Fenton and photoelectro-Fenton processes were used as the degradation methods. H2O2, produced by the reduction of oxygen at carbon cathode reacted with dissolved metal ions to form hydroxyl radicals, which in turn reacted with PCOC sequentially to degrade the aromatic ring. The effects of using different [Fe2+]/[PCOC]0 and the effect of replacing Fe2+ by Mn2+ ion have been examined. It was found that degradation rate was increased with increasing [Fe2+]/[PCOC]0 ratio from 2 to 4. However, the total charge utilized during the treatment was also increased. The efficiency of PCOC degradation was observed to be higher when Mn2+ was used as the catalyst. The mineralization of aqueous solutions of PCOC, withdrawn from the reactor at certain time interval, has been followed by total organic carbon (TOC) decay and dechlorination. A fast and complete degradation of the aromatic ring was achieved in photoelectro-Fenton system. 41.7% TOC decay and complete dechlorination were observed by consuming only 141.4 C electrical charge during a 300 min photoelectron-Fenton treatment. In the case of electro-Fenton system, 280.7 C electrical charge was consumed during 450 min of electrolysis to attain a similar degradation of PCOC. 14.9% TOC removal and 89.3% dechlorination have been obtained in this system under the applied conditions.  相似文献   
5.
The performance of a submerged membrane bioreactor (sMBR) for municipal wastewater reclamation and re-use was compared with that of a current classic activated sludge process (CASP). The average chemical oxygen demand (COD) of CASP effluent was 75 mg/l, while the average COD of sMBR filtrate was 15 mg/l. In general, COD removal was above 98%. However, the best results were obtained at a sludge rentention time (SRT) of 50 days. The total phosphorus (TP) content of the filtrate decreased to a level <1 mg/l under aerobic conditions in which aeration occurred continuously. It was shown that the filtrate TP and orthoposphate (Orto-P) concentrations increased dramatically during the periods of intermittent aeration because phosphorus is released under anoxic conditions. In the CASP effluent, the average TP and Orto-P were 7.9 mg/l and 7.1 mg/l, respectively. The filtrate was free of suspended solids (SS) and total coliform bacteria. The effluent SS in the CASP was 40 mg/l. The turbidity removal in the sMBR reached almost 99%, i.e. generally less than 1 NTU, while the average turbidity of the CASP effluent was almost 15 NTU. The removal of ammonium nitrogen (NH4+-N) in the sMBR was almost 99.8%. In addition, the nitrate concentration in the filtrate decreased to 2.4 mg/l under both aerobic & anoxic conditions. It was shown that both nitrification and denitrification could be successfully reduced through intermittent aeration. Average total Kjeldehl nitrogen (TKN) and NH4+-N in the CASP effluent were 30.2 mg/l and 20 mg/l, respectively, i.e. the nitrification efficiency was 42.9%, and the denitrification value was not available. When these results are compared with those in the CASP, it indicated that the sMBR could be successfully used for reclamation and re-use of municipal wastewater.  相似文献   
6.
The determining of efficient packaging sizes is a key factor in saving material and transportation costs and also in reducing packaging waste. By analyzing the range of items and their contribution to sales-relevant order structures of a globally operating mail order company, a simplified packing algorithm is proposed. In combination with well-known methodologies, this heuristic provides near optimal solutions improving current packaging of eCommerce companies. It is shown that simple, practical heuristics are sufficient to achieve average material savings of more than 10 %. In order to find efficient packaging sizes, a set of them is generated by discretization of packaging dimensions. Given the set of orders and the set of packaging sizes, a p-median approach is applied to find a specified number of optimal, demand-related packaging sizes.  相似文献   
7.
In this paper, the subspace based classifier, common vector approach (CVA), with the center of gravity (COG) method is used for isolated word recognition. Since the CVA classifier is sensitive to shifts through the time axis, endpoint detection becomes extremely important for the recognition of isolated words. The COG method eliminates the need for endpoint detection. The effects of the COG method and a classical endpoint detection algorithm on the recognition rates of isolated words are investigated. The experimental results show that the COG method yields slightly higher recognition rates than the endpoint detection method in the TI-digit database when CVA is used.  相似文献   
8.
9.
The effective integration of robotics together with magnetic resonance (mr) technology is expected to facilitate the real-time guidance of various diagnostic and therapeutic interventions. Specially designed robotic manipulators are required for this purpose, the development of which is a challenging task given the strong magnetic fields and the space limitations that characterize the mr scanning environment. A prototype mr-compatible manipulator is presented, designed to operate inside cylindrical mr scanners. It was developed for the study of minimally invasive diagnostic and therapeutic interventions in the abdominal and thoracic area with real-time mr image guidance. Initial tests were performed inside a high-field clinical mr scanner and included mr-compatibility tests and phantom studies on image-guided targeting.  相似文献   
10.
Slow pyrolysis of giant mullein (Verbascum thapsus L.) stalks have been carried out in a fixed-bed tubular reactor with (Al2O3, ZnO) and without catalyst at four different temperatures between 400 to 550°C with a constant heating rate of 50°C/min and with a constant sweeping gas (N2) flow rate of 100 cm3/min. The amounts of bio-char, bio-oil, and gas produced were calculated and the compositions of the obtained bio-oils were determined by gas chromatography-mass spectrometry. The effects of pyrolysis parameters, such as temperature and catalyst, on the product yields were investigated. The results show that both temperature and catalyst have significant effects on the conversion of Verbascum thapsus L. into solid, liquid, and gaseous products. The highest liquid yield of 40.43% by weight including the aqeous phase was obtained with 10% zinc oxide catalyst at 500°C temperature. Sixty-seven different products were identified by gas chromatography-mass spectrometry in the bio-oils obtained at 500°C temperature.  相似文献   
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