Panel Data Analysis of Trade Policy Effects on U.S. Textile Industries

By applying a gravity model, the study confirms that devalued currencies of Asian exporters of textile products and liberalization of trade policies have significantly contributed to the increased imports of textile products to the U.S. Implications are derived from the abrogation of the WTO's Agreement on Textiles and Clothing (ATC).International Relations/Trade,

Determinants of U.S. Textile and Apparel Trade

A gravity model using panel data is applied to determine factors affecting textiles and apparel trade flows into the United States. The study confirms that a nation's aggregate output and per unit productivity serve as important determinants of textiles and apparel trade into the U.S., and the exporting country's depreciating exchange rate as well as its lower prices relative to U.S. prices for textiles and apparel play an important role in determining textiles and apparel trade flows to the U.S. market. Since the WTO's multilateral trade restraining policies of the multi-fibre arrangement (MFA) is found to have slowed down imports, its abrogation in 2005 should lead to greater textiles and apparel imports to the U.S.brand equity, brand valuation, real options, food firms, growth option value, Agribusiness, International Relations/Trade,

What is the Brillouin Zone of an Anisotropic Photonic Crystal?

The concept of the Brillouin zone (BZ) in relation to a photonic crystal fabricated in an optically anisotropic material is explored both experimentally and theoretically. In experiment, we used femtosecond laser pulses to excite THz polaritons and image their propagation in lithium niobate and lithium tantalate photonic crystal (PhC) slabs. We directly measured the dispersion relation inside PhCs and observed that the lowest bandgap expected to form at the BZ boundary forms inside the BZ in the anisotropic lithium niobate PhC. Our analysis shows that in an anisotropic material the BZ - defined as the Wigner-Seitz cell in the reciprocal lattice - is no longer bounded by Bragg planes and thus does not conform to the original definition of the BZ by Brillouin. We construct an alternative Brillouin zone defined by Bragg planes and show its utility in identifying features of the dispersion bands. We show that for an anisotropic 2D PhC without dispersion, the Bragg plane BZ can be constructed by applying the Wigner-Seitz method to a stretched or compressed reciprocal lattice. We also show that in the presence of the dispersion in the underlying material or in a slab waveguide, the Bragg planes are generally represented by curved surfaces rather than planes. The concept of constructing a BZ with Bragg planes should prove useful in understanding the formation of dispersion bands in anisotropic PhCs and in selectively tailoring their optical properties.Comment: 9 pages, 6 figure

THz generation using a reflective stair-step echelon

We present a novel method for THz generation in lithium niobate using a reflective stair-step echelon structure. The echelon produces a discretely tilted pulse front with less angular dispersion compared to a high groove-density grating. The THz output was characterized using both a 1-lens and 3-lens imaging system to set the tilt angle at room and cryogenic temperatures. Using broadband 800 nm pulses with a pulse energy of 0.95 mJ and a pulse duration of 70 fs (24 nm FWHM bandwidth, 39 fs transform limited width), we produced THz pulses with field strengths as high as 500 kV/cm and pulse energies as high as 3.1 $\mu$J. The highest conversion efficiency we obtained was 0.33%. In addition, we find that the echelon is easily implemented into an experimental setup for quick alignment and optimization.Comment: 19 pages, 4 figure

Cybercrime and Risks for Cyber Physical Systems

Cyber Physical Systems (CPS) is the integration of computation and physical systems that make a complete system such as the network, software, embedded systems, and physical components. Major industries such as industrial plants, transport, national grid, and communication systems depend heavily on CPS for financial and economic growth. However, these components may have inherent threats and vulnerabilities on them that may run the risk of being attacked, manipulated or exploited by cyber attackers and commit cybercrimes. Cybercriminals in their quest to bring down these systems may cause disruption of services either for fame, data theft, revenge, political motive, economic war, cyber terrorism, and cyberwar. Therefore, identifying the risks has become imperative in mitigating the cybercrimes. This paper seeks to identify cybercrimes and risks that are associated with a smart grid business application system to determine the motives and intents of the cybercriminal. The paper identified four goals to mitigate the risks: as business value, organizational requirements, threat agent and impact vectors. We used the Analytical Hierarchy Process (AHP) to determine the importance of the goals that contribute to identifying cybercrime and risks in CPS. For the results, a case study is used to identify the threat and vulnerable spots and the prioritized goals are then used to assess the risks using a semi-quantitative approach to determine the net threat level. The results indicate that using the AHP approach to identify cybercrime and risk on CPS provides specific risk mitigation goals

What are the most important future water research questions in East Africa?

There are volumes of articles that highlight the importance of making policy decisions based on rigorous and reliable evidence. However, the question of how researchers identify which questions require immediate attention, energy and effort remains elusive. In most academic spaces and Sub Saharan Africa, research agenda-setting is influenced by factors such as the agenda of funding and aid bodies, Universities’ research priority, or the researcher’s interest. In recent times, there have been several exercises to open up the research agenda-setting to a wider audience. In Sub-Saharan Africa, such research exercises are lacking in many spaces and sectors. What is evident in Sub-Saharan Africa is that some of these exercises are, by default, available to a few academicians who have managed to establish their links and initiatives. This has led to uncoordinated efforts in deciding which research questions need to focus on. In 2019, water@leeds, one of the largest interdisciplinary water research group located in the University of Leeds conducted a global survey, requesting the wider global audience to identify priority research questions that researchers need to address and answer in the future. What was different about this exercise was the opportunity it gave for wider audience participation. Thus, practitioners, policymakers, students, non-water experts all had the opportunity to participate. The survey also gained attention and interest in Sub-Saharan Africa. In East Africa, which is the region in focus for this article, we received a total of 151 questions from 21 respondents. In this article, the focus is to present some of the lessons that we gleaned from the questions submitted from the East African participants and to suggest potential research pathways for the East African water sector. We are aware this is a generalist attempt to clump the region together and offer ideas, however, the lessons we hope to offer are general and could be applied on a country and regional basis

Nonlinear two-dimensional terahertz photon echo and rotational spectroscopy in the gas phase

Ultrafast two-dimensional spectroscopy utilizes correlated multiple light-matter interactions for retrieving dynamic features that may otherwise be hidden under the linear spectrum. Its extension to the terahertz regime of the electromagnetic spectrum, where a rich variety of material degrees of freedom reside, remains an experimental challenge. Here we report ultrafast two-dimensional terahertz spectroscopy of gas-phase molecular rotors at room temperature. Using time-delayed terahertz pulse pairs, we observe photon echoes and other nonlinear signals resulting from molecular dipole orientation induced by three terahertz field-dipole interactions. The nonlinear time-domain orientation signals are mapped into the frequency domain in two-dimensional rotational spectra which reveal J-state-resolved nonlinear rotational dynamics. The approach enables direct observation of correlated rotational transitions and may reveal rotational coupling and relaxation pathways in the ground electronic and vibrational state.Comment: 31 pages, 14 figure

The Growth Performance of Triplochiton scleroxylon, Terminalia superba and Ceiba pentandra in Pure and Mixed Stands.

Plantation developers mostly prefer exotic to indigenous tree species in restoration of degraded forests due, perhaps to, inadequate information on indigenous tree plantations to enable them change in that direction. The study was conducted at the Jimira Forest Reserve in the Nkawie Forest District to compare the growth performance of Ceiba pentandra, Terminalia superba and Triplochiton scleroxylonin their pure and mixed stands. Four plots, each divided into four subplots measuring 50m x 50m, of one hectare demarcated represented three pure stands of Ceiba pentandra, Terminalia superba and Triplochiton scleroxylon and one mixed stand of the three species. Simple random sampling was used to a subplot from each plotand diameter and height measurements were taken. The mean growth rates in diameter of Ceiba pentandra, Terminalia superba, and Triplochiton scleroxylon in the pure stands and the mixed stand were 1.73 and 1.61cm/year; 1.77 and 2.02 cm/year; and 2.70 and 2.57 cm/year respectively and those in height were 1.06 and 0.80 m/year; 1.16 and 1.25 m/year; and 1.98 and 1.59 m/year respectively. The statistical analysis carried out to determine the variations in tree diameter and height in the pure and mixed stands indicated no significant differences. Keywords: Growth Performance, Triplochiton scleroxylon, Terminalia superba, Ceiba pentandra, Pure and Mixed Stands. DOI: 10.7176/JNSR/9-4-0