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This paper aims to present the design development and measurement of two aerodynamic slotted X-bands back-to-back planer substrate-integrated rectangular waveguide (SIRWG/SIW) to Microstrip (MS) line transition for satellite and RADAR applications. It facilitates the realization of nonplanar (waveguide-based) circuits into planar form for easy integration with other planar (microstrip) devices, circuits and systems. This paper describes the design of a SIW to microstrip transition. The transition is broadband covering the frequency range of 8–12 GHz. The design and interconnection of microwave components like filters, power dividers, resonators, satellite dishes, sensors, transmitters and transponders are further aided by these transitions. A common planar interconnect is designed with better reflection coefficient/return loss (RL) (S₁₁/S₂₂ ≤ 10 dB), transmission coefficient/insertion loss (IL) (S₁₂/S₂₁: 0–3.0 dB) and ultra-wideband bandwidth on low profile FR-4 substrate for X-band and Ku-band functioning to interconnect modern era MIC/MMIC circuits, components and devices.

Two series of metal via (6 via/row) have been used so that all surface current and electric field vectors are confined within the metallic via-wall in SIW length. Introduced aerodynamic slots in tapered portions achieve excellent impedance matching and tapered junctions with SIW are mitered for fine tuning to achieve minimum reflections and improved transmissions at X-band center frequency.

Using this method, the measured IL and RLs are found in concord with simulated results in full X-band (8.22–12.4 GHz). RLC T-equivalent and p-equivalent electrical circuits of the proposed design are presented at the end.

The measurement of the prototype has been carried out by an available low-cost X-band microwave bench and with a Keysight E4416A power meter in the microwave laboratory.

The transition is fabricated on FR-4 substrate with compact size 14 mm × 21.35 mm × 1.6 mm and hence economical with IL lie within limits 0.6–1 dB and RL is lower than −10 dB in bandwidth 7.05–17.10 GHz. Because of such outstanding fractional bandwidth (FBW: 100.5%), the transition could also be useful for Ku-band with IL close to 1.6 dB.

The purpose of this paper is to gain a better understanding on how metasurfaces behave, in terms of currents in each unit cell. A better knowledge of their behavior could lead to an ad-hoc design for specific applications.

The methodology used is both theoretical and numerical; it is based on circuit theory and on an optimization procedure.

The results show that when the knowledge of the current in each unit cell of a metasurface is needed, the most common approximations currently used are often not accurate. Furthermore, a procedure for the termination of a metasurface, with application-driven goals, is given.

This paper investigates the distribution of the currents in a 2D metamaterial realized with magnetically coupled resonant coils. Different models for the analysis of these structures are illustrated, and the effects of the approximations they introduce on the current values are shown and discussed. Furthermore, proper terminations of the resonators on the boundaries have been investigated by implementing a numerical optimization procedure with the purpose of achieving a uniform distribution of the resonator currents. The results show that the behavior of a metasurface (in terms of currents in each single resonator) depends on different properties; as a consequence, their design is not a trivial task and is dependent on the specific applications they are designed for. A design strategy, with lumped impedance termination, is here proposed.

This case requires students to evaluate alternative dual-share-class corporate structures that allow companies and entrepreneurs to pursue profit with purpose. The case explores Impact Makers, an IT consulting company based in Richmond, Virginia. While original founders of the firm hold all voting rights, the cash flow rights belong to two nonprofits setting the stage for a Newman's Own model of management consulting. The case discusses whether and how the alternative corporate structure aids the firm's overall strategy to attract top-quality employees, pay them competitive salaries, and provide superior service to its clients while donating 100% of its lifetime value to charitable causes, largely through partnerships with various nonprofit organizations. More importantly, the case asks students to evaluate how such a dual-share-class and dual-purpose company can raise capital to fund continued growth.

The case opens with CEO Michael Pirron reminding himself of all the questions he had run through to execute a strategy to further grow Impact Makers' consulting business both through expanding a menu of services and through conquering new geographical markets. To do either, or both, the company needed a cash infusion. Internal cash was limited, as up to 40% of it flowed to charitable partners, demonstrating Impact Makers' commitment to its mission. Raising debt for a company without fixed assets was challenging and time consuming. Complicating it all was that being structured as a nonstock corporation rendered equity raising difficult. Could Impact Makers raise money to grow and stay true to community values at the same time?

This study employs Stein Rokkan's methodological approach to analyse state formation in the Greater Middle East. It develops a conceptual framework distinguishing colonial, populist and democratic pacts, suitable for analysis of state formation and nation-building through to the present period. The framework relies on historical institutionalism. The methodology, however, is Rokkan's. The initial conceptual analysis also specifies differences between European and the Middle Eastern state formation processes. It is followed by a brief and selective discussion of historical preconditions. Next, the method of plotting singular cases into conceptual-typological maps is applied to 20 cases in the Greater Middle East (including Afghanistan, Iran and Turkey). For reasons of space, the empirical analysis is limited to the colonial period (1870s to the end of World War 1). Three typologies are combined into one conceptual-typological map of this period. The vertical left-hand axis provides a composite typology that clarifies cultural-territorial preconditions. The horizontal axis specifies transformations of the region's agrarian class structures since the mid-19th century reforms. The right-hand vertical axis provides a four-layered typology of processes of external intervention. A final section presents selected comparative case reconstructions. To the authors' knowledge, this is the first time such a Rokkan-style conceptual-typological map has been constructed for a non-European region.

The purpose of this study is to examine the effect of the coopetition strategy (CS) (the simultaneous pursuit of collaboration and competition) on sustainable performance (SP) through the serial mediation of knowledge sharing (KS) and open innovation (OI).

A structured questionnaire was used to gather data from corporate business enterprises, and partial least squares structural equation modeling was used for analysis.

Empirical evidence supports the coopetition strategy's role in enhancing KS, which in turn fosters OI, leading to improved SP. It has also been concluded that KS and OI have a significant serial mediation effect on the relationship between CS and SP.

Through the integration of KS and inward-outward open innovation, the coopetition model enables coopetitors leverage each other’s resources and capacities for mutual sustainability. To fully benefit from it, small and medium-sized enterprises (SMEs) in the Gulf Cooperation Council (GCC) must change their perception of free competition and actively engage in coopetition activities, particularly in the realms of knowledge and OI.

The most novel contribution of this study to the growing body of knowledge on SP is the establishment of empirical evidence regarding the crucial role of a serial mediation of KS and OI in the relationship between CS and SP. Unlike earlier research, this study provides a structured perspective and understanding of how and why CS, KS and OI were leveraged to enhance the SP of SMEs.