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41.
A tempering cycle was developed via heat treatment to study the decomposition of detrimental martensite–austenite (MA). The heat treatment cycle was found to preferentially decompose hard MA with a critical size of ≥1?µm, which decreases the hardness of these microconstituents after tempering at 300°C for 10?min. The dislocation density inside the MA and in the surrounding matrix was also decreased. Tempering of the X80 weldments containing MA reveals a similar decomposition behaviour. During transverse weld tensile testing of welds, a fracture occurred in the heat-affected zone due to void formation at the MA/ferrite interfaces. However, a fracture occurred in base metal with improved strength and ductility after tempering, in comparison to the fracture in the heat-affected zone of as-welded samples.  相似文献   
42.
Ten popular disperse dyes with different energy levels and chemical constitutions were used to compare their exhaustion, color yield, and colorfastness on polylactide (PLA) and poly(ethylene terephthalate) (PET). Only two out of the 10 dyes had exhaustions higher than 80% on PLA at 2% owf. Five out of the 10 dyes had exhaustions less than 50%. All 10 dyes had more than 90% exhaustion on PET, whereas six of them had exhaustions of 98% or higher. There was no obvious pattern as for which energy level or which structure class provided dye exhaustion better than that of others. Although PLA had lower disperse dye exhaustion than that of PET, it had higher color yield. Based on the 10 dyes examined, the color yield of PLA was about 30% higher than that of PET. This means that even with low dye uptake, PLA could have a similar apparent shade depth as that of PET if the same dyeing conditions are applied. Our study supported that the lower reflectance, or reflectivity, of PLA contributes to the higher color yield of PLA than that of PET. A quantitative relation between the shade depth of PLA and PET based on their dye sorption was developed. Disperse dyes examined had lower washing and crocking fastness on PLA than on PET. The differences in class were about 0.5 to 1.0. If the comparison was based on the same dye uptake, the differences might be larger. The differences in light fastness between the two fibers were smaller than that in washing and crocking fastnesses. The light fastness of disperse dyes on PLA is expected to be even better if the comparison is based on the same dye uptake on both fibers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3285–3290, 2003  相似文献   
43.
Silicon - Carbon and their compounds were removed successfully through electron beam melting (EBM), so that those areas (contaminated with carbon) of ingot were recycled and reused. During EBM...  相似文献   
44.
An investigation was carried out to determine the prevalence and antibiotic resistance of Salmonella serovars in ducks, their rearing and processing environments in Penang, Malaysia. A total of 531 samples collected from wet markets and duck farms, were examined from August 2009 to October 2010. The overall prevalence of Salmonella serovars was 23.5% (125/531). The 125 Salmonella isolates belong to 10 different serovars namely Typhimirium (29.6%), Enteritidis (12.0%), Gallinarum (2.4%), Braenderup (12.0%), Albany (11.2%), Hadar (20.8%), Derby (6.4%), Weltevreden (1.6%), Newbrunswick (3.4%) and London (0.8%). Salmonella serovars also showed various resistance patterns against 13 different antibiotics. All the serovars were resistant to erythromycin but susceptible to cephalothin, gentamicin and ceftriaxone. Plasmids were detected in 91 (72.8%) of the isolates with sizes ranging from 1.4 to 23.1 Kbp. Our findings provide baseline information on the distribution of Salmonella serovars in ducks, their rearing and processing environments, and indicate that ducks should be considered as an important source of food-borne pathogens.  相似文献   
45.
Readymade garments are the most important export item from Bangladesh, yet the working conditions and fire safety records in the factories are often not up to the standard. Despite a number of initiatives to curb fire accidents in the garment industry, there are still a significant number of fire occurrences in this industry. Unfortunately, there is no comprehensive statistics on the current status of fire provisions and management practices in the readymade garment factories in Bangladesh. Given the management practices (soft issues) are often as important as structural fire safety measures, yet difficult to regulate, this paper develops a fire risk index (FRI), the first of its kind in Bangladesh, for soft parameters in the garment industry. FRI for 60 random garment factories are developed through surprise inspections to understand the current status of fire risk due to inadequacies in the soft parameters. Results show that the mean FRI is 2.8 on a scale of 5.0, which indicates an alarming condition. Locked exit doors, lack of emergency announcement system and lack of fire drills are the three worst performers among the 24 investigated parameters and require immediate attention from the regulators and stakeholders. We also observed a U-shaped relationship between FRI and factory size. Factories that are members of the industry’s trade lobby generally have better fire safety practices than the non-members. Given the importance of the readymade garment sector in many developing countries, poor fire safety record and lack of information on fire safety, our approach of developing an FRI for the industry can be very useful to understand the immediate concerns and thus to curb fatalities and injuries from fire accidents in this sector.  相似文献   
46.
Content authentication, integrity verification, and tampering detection of digital content exchanged via the internet have been used to address a major concern in information and communication technology. In this paper, a text zero-watermarking approach known as Smart-Fragile Approach based on Soft Computing and Digital Watermarking (SFASCDW) is proposed for content authentication and tampering detection of English text. A first-level order of alphanumeric mechanism, based on hidden Markov model, is integrated with digital zero-watermarking techniques to improve the watermark robustness of the proposed approach. The researcher uses the first-level order and alphanumeric mechanism of Markov model as a soft computing technique to analyze English text. Moreover, he extracts the features of the interrelationship among the contexts of the text, utilizes the extracted features as watermark information, and validates it later with the studied English text to detect any tampering. SFASCDW has been implemented using PHP with VS code IDE. The robustness, effectiveness, and applicability of SFASCDW are proved with experiments involving four datasets of various lengths in random locations using the three common attacks, namely insertion, reorder, and deletion. The SFASCDW was found to be effective and could be applicable in detecting any possible tampering.  相似文献   
47.
The readymade garment (RMG) industry plays a vital role in the socio-economic development of Bangladesh, yet the sector suffers from poor fire safety records. Given the lack of fire risk assessment in the industry, this paper develops a Fire Risk Index (FRI) for individual RMG factories and surveys 60 such factories to develop an understanding of the fire safety conditions in the sector. The paper differentiates the risk factors into structural (hard) and management related (soft) parameters and develops FRIs for the structural factors. The FRI for structural parameters is then compared with the FRI for management factors, published earlier. While an overall mean FRI of 2.12 on a 4 point scale indicates that fire safety condition is quite poor, the FRI for soft parameters (1.80) are even lower than the FRI for hard parameters (2.58), indicating the critical importance of the soft parameters in fire safety assessment of the RMG factories. Within the hard parameters, there appears to be more reliance on firefighting and means for escape than on precautionary measures to contain the fire, which could explain the higher frequency of fire occurrences in the industry. FRI for both hard and soft parameters appear to follow a U shaped relationship with factory size, possibly indicating a Kuznet’s effect in fire safety in the garment sector. The poor FRI for hard factors indicates large deviations from safety requirements set in this work and asks for a stricter monitoring and enforcement regime. Improving the performance in the soft parameters, however, would require changes in the safety culture and practices.  相似文献   
48.
Partially crystalline nanosize ZSM-5 with high surface area (678 m2/g) was synthesized successfully without using organic template by a two-step temperature process. Aluminum nitrate was used as aluminum source for the first time to synthesize ZSM-5 materials. The presence of MFI structure of the materials was analyzed by XRD, FTIR, Raman spectroscopy and TEM techniques. Addition of commercial HZSM-5 as a seeding agent to the reactants resulted an increase in crystallinity of the ZSM-5 sample and subsequent decrease in specific surface area. The partially crystalline samples exhibited low microporosity and remarkably high meso/macropore volume with pore diameters around 30 nm.  相似文献   
49.
50.
Due to the difficulties of brain tumor segmentation, this paper proposes a strategy for extracting brain tumors from three-dimensional Magnetic Resonance Image (MRI) and Computed Tomography (CT) scans utilizing 3D U-Net Design and ResNet50, taken after by conventional classification strategies. In this inquire, the ResNet50 picked up accuracy with 98.96%, and the 3D U-Net scored 97.99% among the different methods of deep learning. It is to be mentioned that traditional Convolutional Neural Network (CNN) gives 97.90% accuracy on top of the 3D MRI. In expansion, the image fusion approach combines the multimodal images and makes a fused image to extricate more highlights from the medical images. Other than that, we have identified the loss function by utilizing several dice measurements approach and received Dice Result on top of a specific test case. The average mean score of dice coefficient and soft dice loss for three test cases was 0.0980. At the same time, for two test cases, the sensitivity and specification were recorded to be 0.0211 and 0.5867 using patch level predictions. On the other hand, a software integration pipeline was integrated to deploy the concentrated model into the webserver for accessing it from the software system using the Representational state transfer (REST) API. Eventually, the suggested models were validated through the Area Under the Curve–Receiver Characteristic Operator (AUC–ROC) curve and Confusion Matrix and compared with the existing research articles to understand the underlying problem. Through Comparative Analysis, we have extracted meaningful insights regarding brain tumour segmentation and figured out potential gaps. Nevertheless, the proposed model can be adjustable in daily life and the healthcare domain to identify the infected regions and cancer of the brain through various imaging modalities.  相似文献   
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