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101.
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Control charts are developed to make the specific quality measures for a successful production process and follow normal distribution behaviors. But some real-life practices do not match such practices and exhibit some positively skewed behavior like lognormal distribution. The present study has considered this situation and proposed a monitoring control chart based on lognormal process variation using a repetitive sampling scheme. This concept proved better for detecting shifts as quickly as possible, and compared with the existing concept, results are elaborated through extensive tables. The average run lengths and standard deviations of the run lengths are being used as a performance evaluation measures and computed by using Monte Carlo simulations performed in R language. A real-life situation has been discussed in the example section to strengthen the proposed control chart concept in a real-life situation.  相似文献   
103.
Due to frequent joining and leaving of nodes and better performance, use of flooding algorithms is always proffered in Mobile Ad-hoc Networks (MANETs). A single query transmitted by a node can be received by hundreds of nodes at 3rd or 4th hop. But it is also fact that flooding algorithms provide an opportunity to attackers for launching query flooding attacks. On one side these query flooding attacks results in wastage of valuable processing resources and on the other side they cause in starvation and delay at legitimate user’s end. To solve this problem we proposed attack containment techniques by providing a fair share of processing resources to every node. Fair distribution is achieved by designing different query distribution techniques based on mathematical models. Results obtained through network simulator 2 prove that the proposed solution is resilient against various types of flooding attacks.  相似文献   
104.
Preprocessing the data is an important step while creating neural network (NN) applications because this step usually has a significant effect on the prediction performance of the model. This paper compares different data processing strategies for NNs for prediction of Boolean function complexity (BFC). We compare NNs’ predictive capabilities with (1) no preprocessing (2) scaling the values in different curves based on every curve’s own peak and then normalizing to [0, 1] range (3) applying z-score to values in all curves and then normalizing to [0, 1] range, and (4) logarithmically scaling all curves and then normalizing to [0, 1] range. The efficiency of these methods was measured by comparing RMS errors in NN-made BFC predictions for numerous ISCAS benchmark circuits. Logarithmic preprocessing method resulted in the best prediction statistics as compared to other techniques.  相似文献   
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106.
Radioisotope plexography seems as easy and innocuous as routine brain scanning. An introductory method is given which could be improved. The choroid plexuses of the four ventricles were well visualized in 15 patients. Consideration is given to the possible labeling process. Besides its morphological value, the test could give interesting clues in the dynamic study of hydrocephalus.  相似文献   
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The jute-plastic composite was prepared by shaking the preirradiated jute fibers (by gamma rays) in a deoxygenated aqueous methyl methacrylate (MMA) solution that contained surfactant and a ho-mopolymer inhibitor. The total dose, dose rate, monomer concentration, reaction time, and temperature were optimized; the jute fibers preirradiated at a 3-Mrad dose at a 100-krad/h dose rate yielded maximum MMA grafting under the above experimental conditions when the jute substrates were shaken for 3 h at 80°C in a deoxygenated 10% MMA aqueous solution containing 1% nonionic surfactant and 0.2% homopolymerization inhibitor. The composite was characterized by infrared and differential scanning calorimetric analyses; the results revealed that preirradiated jute fibers were found to be grafted with MMA in the experimental conditions. The weathering effect and water absorption ability of the composite were determined and found that ungrafted jute samples lost both tenacity and stretchability by the weathering test, whereas the grafted jute samples retained strength (tenacity) even though these were subjected to a severe weathering test up to 105 h. The equilibrium moisture content sharply decreased with an increase in grafting up to the 15% grafting level, after which it was found to be very steady.  相似文献   
110.
Polymers of urethane diacrylate containing an aliphatic or aromatic backbone chain were prepared in the presence of a number of monofunctional and polyfunctional monomers under UV curing. These monomers have different glass transition temperatures ranging from — 110° to 250°C. Film hardness, gel content, tensile properties, and shape recovery characters of these polymers were determined. A correlation between the glass transition temperatures and these properties was established. The monomer N-vinyl pyrrolidone demonstrated the best performance in the preparation of polymers. Some of these polymer films have achieved a unique character of shape recovery phenomenon.  相似文献   
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