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A two-fold adaptive dynamic quadrilateral relay is developed in this research for protecting
Thyristor-Controlled Series Compensator (TCSC)-compensated transmission lines (TLs). By
investigating a new tilt angle and modifying the Takagi method to recognize the fault zone identifier,
the proposed relay adapts its reactive reach and resistive reach separately and independently. The
investigated tilt angle and identified fault zone use the TCSC reactance to compensate its effect
on the TL parameters and system homogeneity. Excessive tests are simulated by MATLAB on the
non-homogenous network, IEEE-9 bus system and further tests are carried out on IEEE-39 bus
system in order to generalize and validate the efficiency of the proposed approach. The designed
trip boundaries are able to detect wide range of resistive faults under all TCSC modes of operations.
The proposed approach is easy to implement as there no need for data synchronization or a high
level of computation and filtration. Moreover, the proposed adaptive dynamic relay can be applied
for non-homogeneity systems and short as well as long TLs which are either TCSC-compensated or
-uncompensated TLs.

A two-fold adaptive dynamic quadrilateral relay is developed in this research for protecting Thyristor-Controlled Series Compensator (TCSC)-compensated transmission lines (TLs). By investigating a new tilt angle and modifying the Takagi method to recognize the fault zone identifier, the proposed relay adapts its reactive reach and resistive reach separately and independently. The investigated tilt angle and identified fault zone use the TCSC reactance to compensate its effect on the TL parameters and system homogeneity. Excessive tests are simulated by MATLAB on the non-homogenous network, IEEE-9 bus system and further tests are carried out on IEEE-39 bus system in order to generalize and validate the efficiency of the proposed approach. The designed trip boundaries are able to detect wide range of resistive faults under all TCSC modes of operations. The proposed approach is easy to implement as there no need for data synchronization or a high level of computation and filtration. Moreover, the proposed adaptive dynamic relay can be applied for non-homogeneity systems and short as well as long TLs which are either TCSC-compensated or -uncompensated TLs.

Deep drawing is an important sheet metal forming process that appears in many industrial fields. It involves pressing a blank sheet against a hollow cavity that takes the form of the desired product. Due to limitations related to the properties of the blank sheet material, several drawing stages may be needed before the required shape and dimensions of the final product can be obtained. Heat treatment may also be needed during the process in order to restore the formability of the material so that failure is avoided. In this paper, the problem of minimizing the number of drawing stages and heat treatments needed for the multistage deep drawing of cylindrical shells is addressed. This problem is directly related to minimizing manufacturing costs and lead time. It is required to determine the post-drawing shell diameters along with whether heat treatment is to be conducted after each drawing stage such that the aforementioned objectives are achieved and failure is avoided. Conventional computer-aided process planning (CAPP) rules are used to define the search space for a dynamic programming (DP) approach in which both the post-drawing shell diameter and material condition are used to define the states in the problem. By discretizing the range of feasible shell diameters starting from the initial blank diameter down to the final shell diameter, the feasible transitions from state to another is represented by a directed graph, based upon which the DP functional equation is easily defined. The DP generates a set of feasible optimized process plans that are then verified by carrying out finite element analysis in which the deformation severity and the resulting strains and thickness variations are investigated. Two case studies are presented to demonstrate the effectiveness of the developed approach. The results suggest that the proposed approach is a valuable, reliable and quick computer aided process planning approach to this complicated problem.

In this paper, the problem of minimizing the number of drawing stages and heat treatments needed for the multi-stage deep drawing of cylindrical shells is addressed. A conventional rule-based computer-aided process planning (CAPP) is utilized within a dynamic programming approach to generate a set of alternative optimal process plans. A finite element analysis is carried out to guide the selection of the appropriate process parameters and to verify the applicability of the selected process plans. A case study is presented to demonstrate the developed approach, and the results suggest that the combination of rulebased CAPP, dynamic programming and finite element validation could be a valuable, reliable and quick computer aided process planning approach to this complicated problem.