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In the present exploration, it was attempted to understand the creep‐fatigue (CF) deformation micromechanisms of alloy CM 247 DS LC by conducting low‐cycle fatigue (LCF) and CF tests employing strain amplitude ranging from 0.6% to 1.0% at T = 850°C in the air and performing extensive electron microscopic examinations. The cyclic life of the alloy lessens for all CF tests conducted at 1 and 5 minute dwell time in comparison to LCF tests. Transmission electron microscopy (TEM) examinations confirmed that during CF tests substructure consists of dislocation loop, mixed dislocations, and γ' rafting, a typical creep deformation signature of nickel‐base superalloys, it also consists of features observed during fatigue deformation such as anti‐phase boundary (APB)‐coupled dislocations inside γ' precipitates and local tangles of dislocations. This confirms that the deformation of CF‐tested specimens is ascribed to the synergistic effect of both creep and fatigue. This fact was further verified by scanning electron microscopic (SEM) examinations. [ABSTRACT FROM AUTHOR]

Duck production has the potential to play a major role in agricultural economy. Asian countries alone contribute 84.2% of total duck meat produced in the world. Driven by the demand of processed foods among consumers, the global duck meat market is expected to grow at a steady pace, reaching a value of about $11.23 billion in the coming years. Duck meat has higher muscle fibre content in breast meat compared to chicken, and is considered as red meat. Moreover, due to a higher fat content (13.8%) than chicken and a stronger gamey flavour, duck meat can be less appreciated by the consumer. Development and diversification of ready-to-eat duck meat products is expected to increase consumption levels. Hence, the status of duck meat production, physicochemical properties, processing, including traditional products, and development of novel value-added ready-to-eat products from spent duck meat is discussed in detail to explore its importance as an alternative to chicken. [ABSTRACT FROM AUTHOR]

When implementing the kanban method in non-serial production lines, an interesting prioritization problem arises. Often a single server station will be linked with M different downstream stations via M separate kanban loops. Then the K-priority problem may be described as determining which kanban card should be processed next, given that empty cards are waiting in more than one loop. The objective in prioritizing the kanbans is to reduce back order or shortage costs and inventory costs at the downstream stations. Utilizing the theory of Markovian decision process and dynamic programming concepts, a solution to the K-priority problem is developed. This solution is labelled the K- rule, and was found to outperform the first-come-first-served and longest queue rules, plus a cost inclusive heuristic rule, in experimental tests. [ABSTRACT FROM AUTHOR]

This paper provides investigative insights into the impact of routeing flexibility, machine flexibility, and product-mix flexibility on the performance of a manufacturing plant. The study employs simulation modelling as the primary tool. The facility modelled is an automobile engine assembly plant consisting of a FMS (flexible manufacturing systems), job shop, and assembly line. A variety of experiments, with the FMS exhibiting one or more of the above three flexibilities at different levels, were simulated on the model. In each experiment the manufacturing performance as given by flow time and work-in-process inventory was tracked. The experiments focused first on the FMS itself, and then on the entire plant. Measures for the three flexibilities are introduced. The simulation results are analysed in detail. The results indicate significant performance benefits in context of the FMS, but little in context of the overall plant. [ABSTRACT FROM AUTHOR]

This facility layout of a flexible manufacturing system (FMS) involves the positioning of cells within given boundaries, so as to minimize the total projected travel time between cells. Defining the layout includes specifying the spatial coordinates of each cell, its orientation in either a horizontal or vertical position, and the location of its load/unload point. We refer to this problem as the FMS facility layout problem (FLP). In this paper we present a four-step heuristic methodology for solving the FLP. This heuristic combines variable partitioning and integer programming methods to generate an open field type of layout. [ABSTRACT FROM AUTHOR]

The presence of physical layer impairments (PLIs) in high-speed optical virtual private network (OVPN) over wavelength-division multiplexing/ dense-wavelength division multiplexing network degrades the connection quality (CQ). The quality can be numerically expressed as the quality factor (Q-Factor) of the connection. The CQ can be further affected by the increasing demand of connections and data speed. It is important to have an efficient OVPN control manager (OVPNCM) to maintain the CQ. OVPNCM can ensure better quality of transmission to the OVPN clients. Traditional routing and wavelength assignment (RWA) algorithms have less regards to the PLIs and cannot provide guaranteed OVPN connection (OVPNC) quality. In order to achieve a guaranteed CQ, we proposed a wavelength assignment (WA) scheme and a hybrid crosstalk model based on linear in-band and nonlinear four-wave mixing crosstalk. The performance of the proposed WA scheme with the hybrid crosstalk model is demonstrated. The results show that the proposed hybrid crosstalk model with WA scheme not only provides a guaranteed OVPNC, but also improves the OVPN performance in terms of blocking probability. [ABSTRACT FROM PUBLISHER]

Intensive characterization studies of iron ore slime carried out by X-ray diffraction spectroscope (XRD), scanning electron microscope (SEM-EDS), field emission scanning electron microscope (FESEM), and quantitative mineralogical evaluation by scanning electron microscope (QEMSCAN) are discussed. In slimes, mineral phases like hematite, goethite, gibbsite, kaolinite, and quartz are present in a complex and intricate way. SEM-EDS and QEMSCAN studies indicate that significant amounts of aluminum are associated with both ochreous and vitreous goethite. Hematite and goethite phases are contaminated with some amount of alumina and silica. The liberation of hematite in the coarser fraction (+500 µm) is only 20.6% compared to 40% in the finer fraction (−500 µm) size. A flow sheet, comprising of hydrocyclone and magnetic separation techniques, has been developed to produce an iron concentrate containing ∼63% Fe with 70.7% weight recovery from a feed sample containing 56.8% Fe, 5.1% SiO2, and 6.4% Al2O3. [ABSTRACT FROM PUBLISHER]