This study aims to find dynamic interaction between domestic investment, foreign direct investment, and economic growth in Pakistan for the period 1976-2010. Phillips and Perron (PP) test is used to assess unit root in the concerned data series. Johansen cointegration approach applied to examine the long run relationship and Toda-Yamamoto causality approach is exercised to evaluate causal linkages. Besides foreign direct investment inflow to Pakistan and domestic investments variables, this study also used GDP as a third variable in order to avoid misspecification problems in the model and also to know the interrelationship between the variables. The empirical findings of this study reveal the existence of long run relationship between domestic investments, foreign direct investment, and economic growth, further supported by Toda-Yamamoto causality, and bidirectional causality has been found between FDI and domestic investment implying that both domestic investment and FDI cause each other.

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This paper presents novel electromagnetic bridge energy harvesters (BEHs) utilizing bridge vibrations and ambient wind surges to power wireless sensor nodes used for bridges' health monitoring. The developed BEHs are cantilever-type and are comprised of a wound coil, permanent magnet, an airfoil, cantilever beam, and a support. Harvesters are characterized in-lab under different vibration levels and are subjected to variable speed air surges. The harvesters exhibit multiresonant frequencies; prototype I has resonant frequencies of 3.6, 14.9, and 17.6 Hz. However, 7.6, 33, and 45 Hz are the resonant frequencies for prototype II. Under vibration testing, prototype I produced a maximum voltage of 206 mV and an optimum power of 354.51 μW at a frequency of 3.6 Hz and 0.4g acceleration. However, at a frequency of 7.6 Hz and 0.6g acceleration, prototype II showed the capability of generating a maximum voltage of 430 mV and an optimum power of 2214.32 μW. Moreover, when BEHs are characterized under variable speed air surges, prototype I generated a load voltage of 19 mV and a power of 7.84 μW at an air speed of 9 m/s; however, 22 mV and 9.14 μW load voltage and power, respectively, are developed by prototype II at 6 m/s air speed.

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The relationship between foreign direct investment (FDI) inflows and economic growth in host countries is a heavily debated issue. Although some studies have found evidence of the positive impact of FDI on economic growth, others have revealed the opposite result. Studies that examined the causality between FDI and gross domestic product (GDP) also have found evidence of unidirectional causality and, in some cases, a bidirectional causality. This study investigated the causal nexus between FDI and GDP in Bangladesh by employing standard time-series econometric tools, namely, augmented Dickey-Fuller, augmented Dickey-Fuller generalized least square, Kwiatkowski-Phillips-Schmidt-Shin, and Lee-Strazicich unit root tests to check stationarity, augmented autoregressive distributed lag (augmented ARDL) bounds testing approach to check cointegration, and Granger causality to explore the direction of causality. The augmented ARDL model found a long-run relationship between FDI and GDP. In addition, the error correction model and Granger causality results indicated the presence of a unidirectional causality running from GDP to FDI.

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Even though dual-comb-based systems are employed almost routinely nowadays in an ever-increasing number of applications, an efficient combination of this effective technique with an imaging arrangement, which would undoubtedly revolutionize hyperspectral imaging, had not yet been demonstrated. Here we present, to our knowledge, the first hyperspectral dual-comb imaging system in which interferograms are directly detected by a video camera. The system, based on a dual-comb scheme capable of consistently generating interferograms at a rate of 1 Hz and below, combines fast hyperspectral imaging with unprecedented optical resolution and fully multiplex operation. Various proof-of-principle experiments demonstrating hyperspectral imaging of molecular resonances have proved that the direct hyperspectral dual-comb imaging method presented here is capable of characterizing a scene with super-fine resolution in a narrow optical span within 1 s.

Laser direct metal deposition (LDMD) has developed from a prototyping to a single metal manufacturing tool. Its potential for creating multimaterial and functionally graded structures is now beginning to be explored. This work is a first part of a study in which a single layer of Inconel 718 is deposited on Ti-6Al-4V substrate. Single layer tracks were built at a range of powder mass flow rates using a coaxial nozzle and 1.5 kW diode laser operating in both continuous and pulsed beam modes. This part of the study focused on the experimental findings during the deposition of Inconel 718 powder on Ti-6Al-4V substrate. Scanning electron microscopy (SEM) and X-ray diffraction analysis were performed for characterization and phase identification. Residual stress measurement had been carried out to ascertain the effects of laser pulse parameters on the crack development during the deposition process.