Publication Date: 2004
International Journal of Quality and Reliability Management (0265671X)21(7)pp. 731-746
In almost all of the existing resources of failure mode and effect analysis (FMEA), "severity" is being determined from the designers' point of view, not from the customers' side. In this paper, a new approach is proposed to enhance FMEA capabilities through its integration with Kano model. This evolves the current approaches for determination of severity and "risk priority number" (RPN) through classifying severities according to customers' perceptions. It supports the nonlinear relationship between frequency and severity of failure. Also a new index called "correction ratio" (Cr) is proposed to assess the corrective actions in FMEA. The findings of a short case study highlight the gap between managers and customers in prioritising a set of failures and the difference between RPN and Cr prioritisations, caused by target failure frequencies. The proposed approach enables managers/designers to prevent failures at early stages of design, based on customers who have not experienced their products/services yet. © Emerald Group Publishing Limited.
Publication Date: 2004
Linear Algebra and Its Applications (00243795)390(1-3)pp. 345-355
Let R be a non-commutative ring. The commuting graph of R denoted by Λ (R), is a graph with vertex set R \ Z(R), and two distinct vertices a and b are adjacent if ab = ba. In this paper we investigate some properties of Λ(R), whenever R is a finite semisimple ring. For any finite field F, we obtain minimum degree, maximum degree and clique number of Λ(M n (F)). Also it is shown that for any two finite semisimple rings R and S, if Λ(R) ≃ Λ(S), then there are commutative semisimple rings R1 and S1 and semisimple ring T such that R ≃T × R1, S ≃ T × S1 and |R1| = |S1|. © 2004 Elsevier Inc. All rights reserved.
Afshani, P.,
Ghandehari, M.,
Ghandehari, M.,
Hatami h., H.,
Tusserkani, R.,
Zhu, X. Publication Date: 2005
Journal of Graph Theory (03649024)49(4)pp. 325-335
This paper proves that if G is a graph (parallel edges allowed) of maximum degree 3, then χc′(G) ≤ 11/3 provided that G does not contain H1 or H2 as a subgraph, where H1 and H2 are obtained by subdividing one edge of K23 (the graph with three parallel edges between two vertices) and K4, respectively. As χc′(H1) = χ c′(H2) = 4, our result implies that there is no graph G with 11/3 < χc′(G) < 4. It also implies that if G is a 2-edge connected cubic graph, then χc′(G) ≤ 11/3. © 2005 Wiley Periodicals, inc.
Publication Date: 2005
Discrete Mathematics (0012365X)293(1-3)pp. 121-127
A critical set in an n×n array is a set C of given entries, such that there exists a unique extension of C to an n×n Latin square and no proper subset of C has this property. For a Latin square L, scs(L) denotes the size of the smallest critical set of L, and scs(n) is the minimum of scs(L) over all Latin squares L of order n. We find an upper bound for the number of partial Latin squares of size k and prove thatn2-(e+o(1))n10/6≤maxscs(L)≤n2- π2n9/6.This improves on a result of Cavenagh (Ph.D. Thesis, The University of Queensland, 2003) and disproves one of his conjectures. Also it improves the previously known lower bound for the size of the largest critical set of any Latin square of order n. © 2005 Elsevier B.V. All rights reserved.
Darvizeh m., M.,
Haftchenari h., ,
Darvizeh a., A.,
Ansari, R.,
Alijani a., Publication Date: 2005
WSEAS Transactions on Information Science and Applications (17900832)2(8)pp. 1195-1201
In this study a composite cylindrical shell is loaded under a steady-state axisymmetric voltage and analyzed using a semi-analytical finite element method. An attempt has been made to define a critical buckling voltage for a single layer cylindrical composite shell under a clamped-clamped boundary condition at different fiber orientation and length to radius ratios. The voltage to cause instability is derived from fundamental equations of the piezoelectric constitutive relations. Critical buckling voltage applied to a cylindrical composite shell can be determined by employing a piezoelectric actuator.
Publication Date: 2006
Total Quality Management and Business Excellence (14783363)17(5)pp. 567-587
Since customers are not all created equal, it could not be overemphasised that a precise knowledge of Customer Requirements (CR) holds the key to business success. This paper offers Customer Requirements Segmentation (CRS) as a novel technique for categorizing CR with precision. CRS involves three different types of segmentation according to: service encounters or the service provided within each service encounter (CRS-I); customers' characteristics, e.g. age, gender, etc (CRS-II); and prioritized CR importance (CRS-III). Starting with a comprehensive list of Service Quality Dimensions (SQD), the CRS-I, II and IIIs will successively emerge. Although Quality Function Deployment (QFD) has been widely used in analysing and eventually delivering what the customers want, its implementation has not always been effective. CRS would help overcome some of the major difficulties in QFD implementation which are particularly acute in the Service Sector, namely: in ascertaining the ambiguities in the voice of the customer (VoC); in handling large houses of quality (HoQ); and in resolving conflicts among different variety of CR. A case study on using CRS to analyse the service encounter at the front desk of a four-star hotel will be presented in order to demonstrate CRS in action. The implications of the findings are discussed in detail.
