Evaluation of the Implementation of an Abstract Interpretation Algorithm using Tabled CLP

CiaoPP is an analyzer and optimizer for logic programs, part of the Ciao Prolog system. It includes PLAI, a fixpoint algorithm for the abstract interpretation of logic programs which we adapt to use tabled constraint logic programming. In this adaptation, the tabling engine drives the fixpoint computation, while the constraint solver handles the LUB of the abstract substitutions of different clauses. That simplifies the code and improves performance, since termination, dependencies, and some crucial operations (e.g., branch switching and resumption) are directly handled by the tabling engine. Determining whether the fixpoint has been reached uses semantic equivalence, which can decide that two syntactically different abstract substitutions represent the same element in the abstract domain. Therefore, the tabling analyzer can reuse answers in more cases than an analyzer using syntactical equality. This helps achieve better performance, even taking into account the additional cost associated to these checks. Our implementation is based on the TCLP framework available in Ciao Prolog and is one-third the size of the initial fixpoint implementation in CiaoPP. Its performance has been evaluated by analyzing several programs using different abstract domains.

Nonlinear Stability Analysis of Sandwich Wide Panels—Part II: Postbuckling Response

The nonlinear post-buckling response of sandwich panels based on the extended high-order sandwich panel theory (EHSAPT) is presented. The model includes the transverse compressibility, the axial rigidity, and the shear effect of the core. Both faces and core are considered undergoing large displacements with moderate rotations. Based on the nonlinear weak form governing equations, the post-buckling response is obtained by the arc-length continuation method together with the branch switching technique. Also, the post-buckling response with imperfections is studied. The numerical examples discuss the post-buckling response corresponding to global buckling and wrinkling. It is found that due to the interaction between faces and core, localized effects may be easily initiated by imperfections after the sandwich structure has buckled globally. Furthermore, this could destabilize the post-buckling response. The post-buckling response verifies the critical load and buckling mode given by the buckling analysis in part I. The axial rigidity of the core, although it is very small compared to that of the faces, has a significant effect on the post-buckling response.

Employee, branch, and brand switching: the role of linguistic choice, use and adaptation

Purpose The purpose of this study is to explore how service employee choice and use of language to initiate and maintain conversation with second generation immigrant customers (SGIC) influence customer evaluation of the service encounter, and whether such employee acts may lead customers to employee switching, branch switching (i.e. switching from one to another location within the same brand) and/or brand switching (switching to another brand altogether). Design/methodology/approach A scenario-based between-subjects experiment of 4 (employee: match, adapt, bilingual, no adapt) × 2 (fast food, post office) × 2 (English, Spanish) was used to examine the SGIC response to service encounters in different contexts arising from employee choice and use of language. These scenarios were complemented with a series of measurement scales. The instruments, which were identical except in scenario sections, were administered on 788 second-generation Mexican American customers, resulting in 271 (fast food) and 265 (post office) effective responses. Findings In both service contexts, when employees initiated conversation that matched (English or Spanish) the customer expectations, the SGIC perceptions of interaction quality was higher as compared to other scenarios, leading to subsequent satisfaction and lower switching intentions (employee and branch). Similarly, interaction quality was higher for adapt scenarios as compared to bilingual or no adapt scenarios. Bilingual customers perceived higher interaction quality in bilingual/no-adapt scenarios when compared to monolingual customers. In both contexts, service quality and satisfaction were associated with employee switching and branch switching, but not with brand switching. Research limitations/implications By utilizing interaction adaptation theory to conceptualize the effects of employee choice and use of language, the study grounds the model and the hypotheses in theoretical bases and provides empirical corroboration of the theory. The study also contributes toward understanding the service encounters from the perspective of an overlooked group of vulnerable customers: second-generation immigrants. Practical implications Service research cautions service providers that a key factor in attracting and retaining customers is having detailed communication guidelines and empowering employees to follow those guidelines. The findings go a step further and underscore the critical role of communication from a managerial standpoint. It is in the interest of service organizations to develop guidelines that will govern employee choice and use of language during service encounters. So doing is commercially justified because unguided employee choice and use of language can result in customer switching and attrition. Social implications The juxtaposition between assigned versus asserted identities is an important one not only in social sciences but also within service research. As service encounters grow increasingly multicultural, the need to educate employees on multiculturally appropriate communication etiquette rises in importance. The findings should encourage service firms and local governments to develop formal communication guidelines that begin with multiculturalism as a central tenet permeating all aspects of employee–employee, employee–customer and customer–customer communications. Service providers ought to take precautionary measures to ensure customers will be empowered to assert their identities in their own terms, if they wish so. Originality/value The study demonstrates how employee choice and use of language during service encounters may thwart SGIC, who might view such employee behaviors as acts of identity assignment and, consequently, feel stigmatized, marginalized and offended; and links such customer experiences to switching behavior through mediatory mechanisms.