Mechanical properties of new low‐nickel cobalt‐free maraging steels

To study the mechanical properties of newly developed low‐nickel cobalt‐free maraging steels, six laboratory series with varied Ti, Mo, and Cr mass contents (0.003‐ 1.65, 0.0074‐ 5 and 0.004‐ 5 %) were studied. The study showed that increasing Ti and Mo contents improve the tensile strength and yield strength without affecting ductility markedly. The chromium alloyed grades M2, M6, M8 and M12 exhibit properties comparable to those of T 250 grade. To investigate the effects of heat treatment temperature on the mechanical properties, the solution treatment was carried out at temperatures varying between 820 and 1100 °C and holding times of 15 min at different cooling rates. The ageing temperature varied from 400 to 500 °C at ageing times of 60, 120 and 240 min, respectively. The ageing response of hardness as a function of temperature at different soaking conditions was determined to optimise the heat treatment conditions. The mechanical properties of the different steels after solution treatment and ageing at optimum temperature and time were determined.     

Effect of freeze storage on the volatiles of butter

The changes in the volatile components of three butter samples were studied during freeze storage for 7.5 months. The amount of carbonyl increased and reached a maximum after 4.5 months of storage. Afterwards the carbonyl decreased. The lactons reached its maximum after storage of 3 month. The increase of the carbonyls caused by peroxidation of unsaturated fatty acids was taken as indication for the deterioration of the butter samples during storage.     

Combining search and trust models in unstructured peer-to-peer networks

Effectiveness of Peer-to-Peer (P2P) systems highly depends on efficiency and scalability of their search algorithms. Moreover, managing trust is a key issue for wide acceptance of P2P computing. Surprisingly, the majority of the available trust systems ignore the underlying search algorithm and assume it is preexisting. We claim that combining search and trust systems yields significant performance gains in terms of network traffic and query success rate. In this paper, we propose a robust and efficient trust based search framework for unstructured P2P networks. Our framework maintains limited size routing indexes combining search and trust data to guide queries to most reputable nodes. By dynamically selecting reputable nodes as score managers, our scheme tracks the reputation of participating peers. In an alternative approach, we aggregate partial reputation values obtained from reverse query paths to introduce a low overhead method for estimating reputation scores of peers. Through P2P network simulation experiments, we find significant performance gains in using our framework.     

Attachment insecurity and perceptions of housework: Associations with marital well-being.

This exploratory study examines the interactive effects of attachment insecurity and perceptions of housework on 2 dimensions of marital well-being--satisfaction and perceptions of fairness. Participants were 148 married couples obtained from an area probability sample as part of a larger study. Multilevel modeling analyses with the couple as the unit of analysis showed that women who scored high and men who scored low on the dimension of attachment anxiety and reported that their spouses performed more routine housework (i.e., prepares meals) also reported being over-benefited. Women who scored high and men who scored low on the dimension of attachment avoidance and reported that their spouses performed more intermittent housework (i.e., yard work) reported greater marital satisfaction. These results highlight the role of attachment orientations in explaining why perceptions of housework may have more or less prominent effects on marital well-being. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An improved approach to fuzzy clustering based on FCM algorithm and extended VIKOR method

Fuzzy C-means algorithm is a fuzzy partitional clustering algorithm. However, accuracy and easy to implement have converted this algorithm to the focus of research, and sensitivity to noisy data is an important and challenging issue in the algorithm, so that in recent years, many studies have been done to improve it. In this paper, a clustering algorithm named Fuzzy VIKOR C-means presented that by utilizing the extended VIKOR method based on targeted displacements in the centroids of the clusters seek to benefit from the flexibility property. Moreover, this algorithm also, considering Dunn’s index, means, and density measures as profit criteria, and DB index and the entropy measures as cost criteria, can reduce the sensitivity to noisy data and can enhance performance and quality of clusters. According to the simulation results and comparison with some recent well-known methods, this approach has an effective role in improving the assessment criteria.

     

Fatty Acids Profile and Chemical Composition of Egyptian Moringa oleifera Seed Oils

Moringa oleifera is grown all over the world as a crop for its nutritious pods, leaves and seeds. The purpose of the present study was to evaluate the oil percentage, density, iodine value, saponification value, acid value and fatty acid profile of Egyptian moringa Seed oils. Moringa seeds were irradiated using ⁶⁰Co at dose levels of 0.0 (control), 5, 10 and 15 kGy and oil was extracted from unirradiated and irradiated samples. Results showed that the oil percentage and density were almost unaffected. Irradiation reduced the iodine value, whereas the acid and saponification values were increased in all irradiated samples. The oil was found to contain high levels of unsaturated fatty acids, especially an omega‐9‐fatty acid (oleic) (up to 76.29 %) at a dose level of 15 kGy. Also at the same dose level, the dominant saturated acids were palmitic, stearic acid and arachidic (the three up to 12.66 %). GC–MS revealed the presence of different compounds (more than 50) in the moringa oil extract, among them alkaloids, terpenoids steroids, saturated and unsaturated fatty acids, aromatic and aliphatic hydrocarbons and polyphenolic compounds. Phenolic and falvonoid were significantly increased by increasing irradiation dose levels. Also, the antioxidant activity of irradiated seed oil increased by increasing the phenolic and flavonoid contents. Moringa oleifera could be grown by wide scale production as a potentially valuable crop. However, isolation of individual compounds and their biological activities needs to be covered in future to enhance its pharmacological importance and to open new avenues of research.     

Cloud-supported framework for patients in post-stroke disability rehabilitation

Given the flexibility and potential of cloud technologies, cloud-based rehabilitation frameworks have shown encouraging results as assistive tools for post-stroke disability rehabilitation exercises and treatment. To treat post-stroke disability, cloud-based rehabilitation offers great advantages over conventional, clinic-based rehabilitation, providing ubiquitous flexible rehabilitation services and storage while offering therapeutic feedback from a therapist in real-time during patients' rehabilitative movements. With the development of sensory technologies, cloud computing technology integrated with Augmented Reality (AR) may make therapeutic exercises more enjoyable. To achieve these objectives, this paper proposes a framework for cloud-based rehabilitation services, which uses AR technology along with other sensory technologies. We have designed a prototype of the framework that uses the mechanism of sensor gloves to recognize gestures, detecting the real-time condition of a patient doing rehabilitative exercises. This prototype framework is tested on twelve patients not using sensor gloves and on four patients wearing sensor gloves over six weeks. We found statistically significant differences between the forces exerted by patients’ fingers at week one compared to week six. Significant improvements in finger strength were found after six weeks of therapeutic rehabilitative exercises.     

Flexible and reconfigurable manufacturing systems paradigms

Reconfigurable Manufacturing System (RMS) is a new manufacturing systems paradigm that aims at achieving cost-effective and rapid system changes, as needed and when needed, by incorporating principles of modularity, integrability, flexibility, scalability, convertibility, and diagnosability. RMS promises customized flexibility on demand in a short time, while Flexible Manufacturing Systems (FMSs) provides generalized flexibility designed for the anticipated variations and built-in a priori. The characteristics of the two paradigms are outlined and compared. The concept of manufacturing system life cycle is presented. The main types of flexibility in manufacturing systems are discussed and contrasted with the various reconfiguration aspects including hard (physical) and soft (logical) reconfiguration. The types of changeability and transformability of manufacturing systems, their components as well as factories, are presented along with their enablers and compared with flexibility and reconfigurability. The importance of having harmonized human-machine manufacturing systems is highlighted and the role of people in the various manufacturing paradigms and how this varies in pursuit of productivity are illustrated. Finally, the industrial and research challenges presented by these manufacturing paradigms are discussed.     

Binary semiconductor oxide nanoparticles on graphene oxide (CdO/CeO<Subscript>2</Subscript>/RGO) for the treatment of hazardous organic water pollutants

CdO/CeO₂/RGO was prepared by a hydrothermal process. The physical properties of CdO/CeO₂/RGO have been investigated by FTIR, XRD, DRS, TEM, SEM and EDX. CdO/CeO₂/RGO was used for sonocatalytic degradation of Ibuprofen (IBP), Rodamin B (RhB) and Methyl orange (MO) under ultrasonic irradiation. The catalytic properties of CdO/CeO₂/RGO were evaluated with the reduction of 4-nitrophenol (4-NP) into 4-aminophenol (4-AP) by NaBH₄. The highest degradation efficiency of IBP in presence of K₂S₂O₈ (91%), RhB (97%) and MO (85%) was observed within 80, 150 and 150 min after the beginning of the reaction, respectively. The reduction efficiency of 4-NP was 79% within reaction time of 70min. Compared to the reduced graphene oxide (RGO) and CdO/CeO₂ nanoparticles, CdO/CeO₂/RGO exhibits excellent sonocatalysis on degradation of IBP, azo dyes and catalysis activity on reduction of 4-NP.