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The accuracy of finite element discretizations modelling one‐dimensional wave propagation problems is presented. The spurious reflections arising from finite/infinite element discretizations for unbounded domain problems are quantified. The error curves, numerically obtained, yield a criterion for rational mesh design. Formulae for minimum discretization ratios are given.

The modelling of soil‐foundation systems and the evaluation of the foundation compliance functions through a finite/infinite element technique is presented. By means of in situ measurements performed upon heavy machinery foundations, the actual dynamic foundation loading condition is computed. The results obtained are used for redesigning the foundations according to maximum allowable vibration patterns. The procedure clearly shows the advantages of the technique, which leads to efficient designs for all types of foundations.

This article explores how strategy formulation affects firm performance to determine whether rational/analytical strategy formulation is more effective than emergent/reflexive strategy formulation. Additionally, the article assesses if such superiority holds for different cultural contexts.

Meta-analysis was performed using the Raju, Burke, Norman, and Landis (RBNL) procedure applied to a dataset of 43 empirical studies reporting 54 effect sizes on strategy–performance relationships.

Implementing a formal strategy formulation process positively relates to firm performance. Rational/analytical formulation approaches are more effective than emergent/reflexive approaches in enhancing firm performance, especially for cultures with low future orientation, high uncertainty avoidance, and high power distance.

The reduced number of published empirical studies limited the scope and generalizability of the results across countries, industries, or firms. This limitation might be especially true for Latin American firms given the absence of relevant studies in this region. Another potential limitation is related to the distinction between strategy formulation and strategy implementation. Given the empirical nature of the studies meta-analyzed, strategic tools are used as a proxy to determine the formulation approach.

Firms that operate in short-term oriented, uncertainty-avoiding, and elitist cultures should favor implementing rational/analytical strategy formulation techniques rather than emergent/reflexive approaches. Although prescriptive recommendations are limited by the lack of studies in Latin America, firms in this region would seem to be better off using rational/analytical strategy formulation approaches.

These findings provide a partial explanation for the varying results yielded by strategy formulation and suggest cultural contexts in which rational/analytical strategy formulation should be more effective than emergent/reflexive approaches.

Este artículo explora cómo la formulación de la estrategia afecta el desempeño de la empresa y busca determinar si la formulación de la estrategia racional / analítica es más efectiva que la formulación de la estrategia emergente / reflexiva. Además, el artículo evalúa si dicha superioridad es válida para diferentes contextos culturales.

El metaanálisis se realizó aplicando el procedimiento de Raju, Burke, Norman y Landis (RBNL) a un conjunto de datos de 43 estudios empíricos que reportaron un total de 54 tamaños de efecto sobre las relaciones estrategia-rendimiento.

La implementación de un proceso formal de formulación de estrategias se relaciona positivamente con el desempeño de la empresa. Los enfoques de formulación racional / analítica son más efectivos que los enfoques emergentes / reflexivos para mejorar el rendimiento de la empresa, especialmente para culturas con baja orientación al largo plazo, alta evitación de incertidumbre y alta distancia al poder.

El reducido número de estudios empíricos publicados limitó el alcance y la generalización de los resultados entre países, industrias o empresas. Esta limitación podría afectar especialmente a las empresas latinoamericanas dada la ausencia de estudios relevantes en esta región. Otra limitación potencial está relacionada con la distinción entre la formulación y la implementación de la estrategia. Dada la naturaleza empírica de los estudios meta analizados, las herramientas estratégicas se utilizan como proxy para determinar el enfoque de formulación.

las empresas que operan en culturas orientadas al corto plazo, que evitan la incertidumbre y que muestran alta distancia al poder deberían favorecer la implementación de técnicas de formulación de estrategias racionales / analíticas en lugar de enfoques emergentes / reflexivos. Aunque las recomendaciones prescriptivas están limitadas por la falta de estudios en América Latina, las empresas en esta región parecen estar mejor utilizando enfoques de formulación de estrategias racionales / analíticas.

estos resultados proporcionan una explicación parcial de los resultados variados producidos por la formulación de la estrategia y sugieren contextos culturales en los que la formulación de la estrategia racional / analítica debería ser más efectiva que los enfoques emergentes / reflexivos.

This paper presents a novel mesoscale RF (mRF) relay that integrates advanced high resolution stereolithography (SL) and micro wire electro discharge machining (μEDM) technologies. Methods and infrastructure for reliable batch assembly of electromechanical actuators and structural parts less than 5 mm³ in volume are described. Switches made using these techniques are expected to have greater power handling capability relative to current micro RF relay products.

The conjecture is that the integration of SL and similar rapid additive manufacturing with other mesofabrication technologies can yield innovative miniature products with novel capabilities. A series of mRF prototypes consisting of a contact mechanism and actuator with return spring were fabricated assembled, inspected, and characterized for electromechanical performance. Characterization results led to specific conclusions regarding capabilities of the mRF product, and the integrated manufacturing technique.

The microassembly apparatus and epoxy‐based fastening system led to durable prototypes within 4 h (excluding a 16‐24 h cure cycle). Relay stroke ranged from 560 to 1,650 μm indicating a relative assembly accuracy of 90 percent. Prototypes demonstrated insertion loss of 1.3 dB at 100 MHz and isolation of better than 30 dB through 300 MHz.

Results indicated that fully functional and robust mesoscale relays are possible using integrated manufacturing with SL. However, prototypes exhibited high contact resistance and lacked assembly precision in the context of contact mechanism stroke. Opportunities exist to reduce contact resistance and switching time.

The research provides a practical new product application for integrated mesoscale rapid manufacturing.

This work represents one of the first examples of a mesoscale relay rapidly manufactured with a combination of μEDM and SL components.

Food markets have gathered a growing attention by tourism researchers and practitioners in recent years. Many destinations have placed food markets as a tourism attraction which allows visitors to discover a territory through its food. Drawing on the understanding of markets as identity and tourism icons, this paper aims to analyze the role of urban food markets in the different stages of the tourist experience from a visitor perspective.

To achieve this, a qualitative design was implemented to interview 18 tourists who visited for the first time the city of Palermo, the capital of the Mediterranean island of Sicily, Italy.

The results of this study show the factors that drive the motivations, the experiences and the satisfaction of visitors to food markets and provide relevant perspectives into the management and marketing of food tourism in urban environments.

The originality of this paper lies on the understanding of the relationships between visitor experiences and urban food markets.

A novel and simple six-band metamaterial absorber is proposed in the terahertz region, which is composed of an I-shaped absorber and circular ring with four gaps and a continuous metal ground plane separated by only 0.125 mm polyimide dielectric substrate. Initially, I-shaped resonator gives three bands at 0.4, 0.468 and 0.4928 THz with the absorptivity of 99.3%, 97.9% and 99.1%, respectively. The purpose of this paper is to improve the number of bands, for which the authors added the circular ring with four gaps, so the simulated metamaterial absorber exhibited six absorption peaks at 0.3392, 0.3528, 0.3968, 0.4676, 0.4768 and 0.492 THz, with the absorption rate of 91.4%, 94.2%, 94.9%, 90.3%, 77.5% and 97.4%, respectively. The surface current distribution and angle independence are explained for all the six frequencies which are used to analyze the absorption mechanism clearly. Structure maximum uses the squares and circles, so it will make the fabrication easy. The multiband absorbers obtained here have potential applications in many engineering technology, thermal radiation, material detection and imaging and optoelectronic areas.

This paper presents the design of the six-band metamaterial absorber which is from the I-shaped resonator and circular ring with four gaps and the metallic ground plane separated by the 0.125 polyimide dielectric substrate. The absorber exhibited six absorption peaks at 0.3392, 0.3528, 0.3968, 0.4676, 0.4768 and 0.492 THz, with the absorption rate of 91.4%, 94.2%, 94.9%, 90.3%, 77.5% and 97.4%, respectively. From the fabrication point of view, the proposed six-band metamaterial absorber has a very simple geometrical structure, and it is very easy to be fabricated.

The authors present a new and simple design of six-band absorber based on an I-shaped absorber and circular ring with four gaps and a metallic ground plane separated by a polyimide layer having the thickness of 0.125 mm. Six different resonance absorption peaks are found at 0.3392, 0.3528, 0.3968, 0.4676 , 0.4768 and 0.492 THz. Surface current distribution and angle independence plot have been studied to understand the absorption behavior of the designed terahertz metamaterial absorber.

The multiband absorbers obtained here have potential applications in many engineering technology, thermal radiation, material detection, security, sensors, imaging and optoelectronic areas.

The objective of this paper is to demonstrate a method for producing embedded horizontal micro‐channels using a commercial line‐scan stereolithography (SL) system. To demonstrate that the method is repeatable, reproducible and capable of producing accurate horizontal micro‐channels, a statistical design of experiments was performed.

Demonstration of the technique was performed using a 3D Systems Viper si2^TM SL system and DSM Somos^® WaterShed^TM resin with polytetrafluoroethylene (PTFE)‐coated wire having diameters of 31.6 and 57.2 μm. By embedding the wire and building around the insert, the down‐facing surfaces were supported during fabrication enabling accurate fabrication of embedded micro‐channel geometries. The fabrication method involved first building an open micro‐channel, interrupting the SL process and inserting the wire, and then capping over the wire with multiple layers. After fabrication, the part with the inserted micro‐wire was post‐cured to harden any uncured resin around the wire. The micro‐channel was produced by simply pulling the wire out of the part. Scanning electron microscope images were used to examine and measure the geometries of the fabricated micro‐channels, and characterization through a statistical analysis was accomplished to show that the process was capable of producing accurate horizontal micro‐channels.

The measured data showed that the micro‐wires were successfully removed from the channels, leaving high quality micro‐channels, where the mean measured diameters for each wire were 2.65 and 2.18 μm smaller than the measured wire diameters (31.6 and 57.2 μm). Based on the statistical results, it is suggested that the method described in this work can rapidly produce repeatable and reproducible circular, embedded, and accurate micro‐channels.

The method developed in the current work was demonstrated on simple straight channels and a statistical study was used to show that the process is capable of repeatedly and reproducibly producing accurate micro‐channels with circular cross‐section; however, future studies are required to extend these procedures to more realistic and complicated geometries that may include non‐straight channel paths and non‐circular cross‐sectional geometries. The process can be used for micro‐channel fabrication with not only circular cross‐sectional geometries as shown here but potentially with a wide range of additional cross‐sectional geometries that can be fabricated into a PTFE‐coated micro‐wire.

This work demonstrates a process using commercial line‐scan SL and embedding a PTFE‐coated micro‐wire that is subsequently removed for producing repeatable and reproducible horizontal embedded micro‐channels of circular cross‐sectional geometries.

Survey of period infinite element developments The first infinite elements for periodic wave problems, as stated in Part 1, were developed by Bettess and Zienkiewicz, the earliest publication being in 1975. These applications were of ‘decay function’ type elements and were used in surface waves on water problems. This was soon followed by an application by Saini et al., to dam‐reservoir interaction, where the waves are pressure waves in the water in the reservoir. In this case both the solid displacements and the fluid pressures are complex valued. In 1980 to 1983 Medina and co‐workers and Chow and Smith successfully used quite different methods to develop infinite elements for elastic waves. Zienkiewicz et al. published the details of the first mapped wave infinite element formulation, which they went on to program, and to use to generate results for surface wave problems. In 1982 Aggarwal et al. used infinite elements in fluid‐structure interaction problems, in this case plates vibrating in an unbounded fluid. In 1983 Corzani used infinite elements for electric wave problems. This period also saw the first infinite element applications in acoustics, by Astley and Eversman, and their development of the ‘wave envelope’ concept. Kagawa applied periodic infinite wave elements to Helmholtz equation in electromagnetic applications. Pos used infinite elements to model wave diffraction by breakwaters and gave comparisons with laboratory photogrammetric measurements of waves. Good agreement was obtained. Huang also used infinite elements for surface wave diffraction problems. Davies and Rahman used infinite elements to model wave guide behaviour. Moriya developed a new type of infinite element for Helmholtz problem. In 1986 Yamabuchi et al. developed another infinite element for unbounded Helmholtz problems. Rajapalakse et al. produced an infinite element for elastodynamics, in which some of the integrations are carried out analytically, and which is said to model correctly both body and Rayleigh waves. Imai et al. gave further applications of infinite elements to wave diffraction, fluid‐structure interaction and wave force calculations for breakwaters, offshore platforms and a floating rectangular caisson. Pantic et al. used infinite elements in wave guide computations. In 1986 Cao et al. applied infinite elements to dynamic interaction of soil and pile. The infinite element is said to be ‘semi‐analytical’. Goransson and Davidsson used a mapped wave infinite element in some three dimensional acoustic problems, in 1987. They incorporated the infinite elements into the ASKA code. A novel application of wave infinite elements to photolithography simulation for semiconductor device fabrication was given by Matsuzawa et al. They obtained ‘reasonably good’ agreement with observed photoresist profiles. Häggblad and Nordgren used infinite elements in a dynamic analysis of non‐linear soil‐structure interaction, with plastic soil elements. In 1989 Lau and Ji published a new type of 3‐D infinite element for wave diffraction problems. They gave good results for problems of waves diffracted by a cylinder and various three dimensional structures.

This paper argues that meanings given to “standardization” and “globalization” might have created some confusion and precipitated potentially misleading research results in the literature. The paper discusses the basic assumptions underlying the marketing function as a necessary point of departure to build a sounder theory around these concepts. Findings confirm the lack of formal definitions of these concepts in the marketing and management literatures. The authors “redefine” the concepts of globalization, standardization, adaptation and customization with the help of the AMA’s and Webster’s dictionaries. The new conceptualization is applied to a brand strategy framework. Preliminary results show that standardization and globalization may be at opposite ends of an evolutionary brand strategy process, whereas adaptation and customization are intermediary stages. The paper discusses the findings and suggests future research possibilities.