Some insights into Malakooti et al . ‘Integrated group technology,cell formation and process planning’ approach

Rajagopalan and Irani (Some comments on Malakooti et al. ‘Integrated group technology, cell formation, process planning, and production planning with application to the emergency room’. Int. J. Prod. Res., 2006, 44, 2265--2276.) provide a critique of Malakooti et al. (Integrated group technology, cell formation, process and production planning with application to the emergency room. Int. J. Prod. Res., 2004, 42, 1769–1786.) integrated cell/process/capacity formation (ICPCF) approach and suggest an improved method for solving the ICPCF problem. Rajagopalan and Irani (2006 Rajagopalan, RIrani, SA. 2006. Integrated group technology, cell formation, process planning, and production planning with application to the emergency room. Int. J. Prod. Res., 44: 2265–2276. Some comments on Malakooti[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) attempt to solve the emergency room layout problem presented in Malakooti et al. (2004) and claim to have obtained an improved solution from their approach (hybrid flowshop layout). Although there are certain advantages of considering Rajagopalan and Irani's (2006 Rajagopalan, RIrani, SA. 2006. Integrated group technology, cell formation, process planning, and production planning with application to the emergency room. Int. J. Prod. Res., 44: 2265–2276. Some comments on Malakooti[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) approach, we believe that their approach for solving ICPCF problems have significant shortcomings.     

Some comments on Chen et al. ‘Production scheduling optimization algorithm for the hot rolling processes’

Blades play an important role in aviation engine, gas turbine and jet engine. Inspecting the blade by optical method is a meaningful work in manufacturing industry. During optical inspecting process, one common problem encountered is that the scanned point cloud is large scale and noisy. In this paper, we present a systematic introduction of simplification, smoothing and parameter extraction with respect to point-sampled blades. First, the moving least square surface is applied to create a geometric deviation, which is used to subdivide and cluster the point cloud. Then, the information entropy in k-neighbourhood is defined to smooth point-sampled surface, meanwhile preserving high curvature feature. Furthermore, the computation method of single/multi section parameters is presented, and test experiments are performed in iCloud3D Blade V1.0. Experimental results demonstrate the feasibility and effectiveness of the proposed method.     

Discussion. A reply to ‘A note on a “Change to group technology”’‡

In the industrial field, the idea of subassembly must be distinguished from the subset one, when considering subassemblies as the only subsets in which all parts are stable. An original approach using the disassembly method, the logical reverse chronology of assembly, and the introduction of a mathematical model describing the liaisons allow us to determine the problems related to the automation of assembly sequences. To do so, the modelling of functional liaisons between parts helps to distinguish a simple contact from an attachment, and subsets from subassemblies. Liaisons between components are described by matrices of half degrees of liaison. These liaisons are extracted automatically from a B-rep model of a mechanical product on CAD. Subassemblies are determined automatically just in time during the determination of disassembly sequences. A limitation of this approach is that as soon as a relation is no more orthogonal to the basic referential, a new referential has to be introduced. An expert will choose the best sequence between sequences which were generating.     

Answer to comment on ‘Noiseless amplification in cavity-based optical systems with an internal two-photon process. II. Self-frequency-doubling laser and second-harmonic generation,self-down-converting laser’

Abstract

A simple method to achieve space-variant pattern recognition is proposed with a typical VanderLugt arrangement, in which the input pattern is modulated by a random binary phase function. The output correlation location can be programmed into the filter function. With the introduction of random binary phase modulation, the impulse response of either phase-only or binary phase-only filter function is not edge enhanced, resulting in higher Horner efficiency. Computer simulations are conducted to verify the proposed method.     

Study on the structural formation of new useful multiporous material ‘nano–meso ZSM-5’ and its application in producing biofuel

New ‘nano–meso ZSM-5’ (NM-ZSM-5) material was successfully synthesised by hydrothermal treatment using silica derived from rice husk. The synthesis of the material involves two steps of crystallisation, including the formation of ZSM-5 zeolite seed and mesoporous structure. The effect of crystallisation time on the formation of mesoporous structure was studied in the range 0–40?h. Samples were characterised by X-ray diffraction, infrared spectroscopy, transmission electron microscopy, Brunauer–Emmett–Teller and ²⁷Al-NMR methods. The results show that the best time for crystallisation is 14?h. The synthesised material has a multiporous structure, including micropore system of ZSM-5 zeolite, mesopore system of MCM-41 and another pore system which has a diameter in the range 10–50?nm (mesoporous system) due to the burning of organic compounds that remain in the material during the calcination process. In addition, the synthesised NM-ZSM-5 achieves crystallinity of approximately 100%. The catalytic performance of NM-ZSM-5 material was evaluated by the catalytic cracking reaction to produce biofuel from vegetable oil sludge. The research proved that NM-ZSM-5 is one of the most suitable catalysts for this process. The catalytic cracking reaction over NM-ZSM-5 yields products that are similar to those of the petroleum cracking process, such as dry gases, liquefied petroleum gas, gasoline, light cycle oil and heavy cycle oil.     

Comment on analysis of X-ray diffraction data in the paper “Structural and size dependence magnetic properties of Mn-doped NiO nanoparticles prepared by wet chemical method" by C. Thangamani et al. [J. Mater. Sci: Mater. Electron. 31, 11101 (2020)]

Journal of Materials Science: Materials in Electronics - In the commented paper, there are some questionable data which should be explained or corrected by the Authors, Thangamani et al. In this...