TERSSE: Definition of the Total Earth Resources System for the Shuttle Era. Volume 2: An Assessment of the Current State-of-the-Art

Results of a state-of-the-art assessment of technology areas which affect the Earth Resources Program are presented along with a functional description of the basic earth resources system. Major areas discussed include: spacecraft flight hardware, remote sensors, data processing techniques and hardware, user models, user interfaces, and operations technology

The Proceedings of the 23rd Annual International Conference on Digital Government Research (DGO2022) Intelligent Technologies, Governments and Citizens June 15-17, 2022

The 23rd Annual International Conference on Digital Government Research theme is “Intelligent Technologies, Governments and Citizens”. Data and computational algorithms make systems smarter, but should result in smarter government and citizens. Intelligence and smartness affect all kinds of public values - such as fairness, inclusion, equity, transparency, privacy, security, trust, etc., and is not well-understood. These technologies provide immense opportunities and should be used in the light of public values. Society and technology co-evolve and we are looking for new ways to balance between them. Specifically, the conference aims to advance research and practice in this field. The keynotes, presentations, posters and workshops show that the conference theme is very well-chosen and more actual than ever. The challenges posed by new technology have underscored the need to grasp the potential. Digital government brings into focus the realization of public values to improve our society at all levels of government. The conference again shows the importance of the digital government society, which brings together scholars in this field. Dg.o 2022 is fully online and enables to connect to scholars and practitioners around the globe and facilitate global conversations and exchanges via the use of digital technologies. This conference is primarily a live conference for full engagement, keynotes, presentations of research papers, workshops, panels and posters and provides engaging exchange throughout the entire duration of the conference

GVSU Press Releases, 2011

A compilation of press releases for the year 2011 submitted by University Communications (formerly News & Information Services) to news agencies concerning the people, places, and events related to Grand Valley State University

Analysis of wind-wave induced erosion in the Venice Lagoon in the last four centuries: field observations and modelling

Tidal systems are subjected to a variety of internal and external drivers whose interplay and feedbacks affect the shape and the morphological evolution of typical tidal landforms such as channel networks, salt marshes and tidal flats. Several studies have been carried out describing the various processes that drive the evolution of tidal landforms (e.g., the hydrodynamic circulation, the consequences of tidal currents and wind waves on sediment dynamics, vertical and horizontal dynamics of salt marshes, sea level rise and human interferences). Understanding the positive feedbacks existing between salt-marsh erosion, tidal-flat widening and deepening and more energetic wave generation by means of observational evidence and numerical models is a critical step to predict the response of tidal landforms to future environmental changes. With this aim we first improved current our knowledge on the ancient configurations of the Venice lagoon through the bathymetric reconstruction of the oldest map, dating back to 1611, providing a realistic representation of its morphological features. This furthermore allowed us to gain new insights on the hydrodynamic changes occurred in the last four centuries. We then compared different existing model approaches, in order to unravel the implications of different assumptions and formulations used to model wave dynamics in shallow tidal basins. Subsequently, we analysed the effects of wave action on marsh boundaries and how the wave field has changed in the last four centuries with the aim of further emphasizing the feedbacks existing between the overall erosion of the Venice Lagoon and the increase in wave power density. Finally, we analysed the bottom shear stress distribution obtained for different configurations of the Venice Lagoon, in order to support the possibility of describing wind-wave induced bottom erosion as a marked Poisson process. The main results from this work highlighted that: I) the most important mophodynamic changes in the Venice Lagoon have started in the last century and were mainly triggered by human interferences; II) the assumptions adopted in different modelling framework strongly influence the computation of the bottom shear stress induced by waves, in particular when very shallow water depths are considered; III) the salt-marsh erosion rate is linearly related to the mean wave power density; IV) the erosive trend of the Venice Lagoon during the last four centuries can be explained also by the increase in wave power density and by the analysis of bottom shear stress distribution; V) wind-wave induced erosion processes over tidal flats can be described as marked Poisson processes for all the past and current lagoon configurations, thus leading important consequences for the prediction of future scenarios and implications for the long-term morphodynamic modelling of tidal environments

GVSU Press Releases, 2012

A compilation of press releases for the year 2012 submitted by University Communications (formerly News & Information Services) to news agencies concerning the people, places, and events related to Grand Valley State University

All-fiber processing of terahertz-bandwidth signals based on cascaded tapered fibers

Tapered single-mode fibers are employed to perform dynamic pulse shaping in a bandwidth of several terahertz. The transfer function of cascaded biconical tapers is controlled by introducing a phase shift into one of them through mechanical stretching. It is a simple and low-cost technique with potential to process signals with bandwidths as large as those allocated by standard optical fiber while introducing little degradation. Femtosecond pulses are shaped to prove the concept. (C) 2013 Optical Society of AmericaThis work was supported by the Generalitat Valenciana programs PROMETEO-2010-087 R&D Excellency and GV/2012/121 Grupos Emergentes.Mas Gómez, SM.; Palací López, J.; Pérez Millán, P.; Lechago Buendía, S.; Monzón-Hernández, D.; Martí Sendra, J. (2013). All-fiber processing of terahertz-bandwidth signals based on cascaded tapered fibers. Optics Letters. 38(23):4954-4957. https://doi.org/10.1364/OL.38.004954S495449573823Lacroix, S., Gonthier, F., Black, R. J., & Bures, J. (1988). Tapered-fiber interferometric wavelength response: the achromatic fringe. Optics Letters, 13(5), 395. doi:10.1364/ol.13.000395Villatoro, J., Monzón-Hernández, D., & Mejía, E. (2003). Fabrication and modeling of uniform-waist single-mode tapered optical fiber sensors. Applied Optics, 42(13), 2278. doi:10.1364/ao.42.002278Monzón-Hernández, D., & Villatoro, J. (2006). High-resolution refractive index sensing by means of a multiple-peak surface plasmon resonance optical fiber sensor. Sensors and Actuators B: Chemical, 115(1), 227-231. doi:10.1016/j.snb.2005.09.006Villatoro, J., Monzón-Hernández, D., & Luna-Moreno, D. (2004). In-line optical fiber sensors based on cladded multimode tapered fibers. Applied Optics, 43(32), 5933. doi:10.1364/ao.43.005933Wang, Z., Sone, H., Tsuji, Y., & Imai, M. (2007). Spectral Phase and Intensity Evolutions of Supercontinuum Generation in a Biconical Tapered Fiber. Optical Review, 14(2), 81-85. doi:10.1007/s10043-007-0081-6Lu, F., & Knox, W. H. (2004). Generation of a broadband continuum with high spectral coherence in tapered single-mode optical fibers. Optics Express, 12(2), 347. doi:10.1364/opex.12.000347Jedrzejewski, K. P., & Kosinski, A. (1997). Wide-band tapered directional coupler. Technology and Applications of Light Guides. doi:10.1117/12.285622Kawasaki, B. S., Hill, K. O., & Lamont, R. G. (1981). Biconical-taper single-mode fiber coupler. Optics Letters, 6(7), 327. doi:10.1364/ol.6.000327Rusu, M., Herda, R., Kivistö, S., & Okhotnikov, O. G. (2006). Fiber taper for dispersion management in a mode-locked ytterbium fiber laser. Optics Letters, 31(15), 2257. doi:10.1364/ol.31.002257Kieu, K., & Mansuripur, M. (2007). Femtosecond laser pulse generation with a fiber taper embedded in carbon nanotube/polymer composite. Optics Letters, 32(15), 2242. doi:10.1364/ol.32.002242Weiner, A. M. (2011). Ultrafast optical pulse shaping: A tutorial review. Optics Communications, 284(15), 3669-3692. doi:10.1016/j.optcom.2011.03.084Liu, X., Premkumar, A., & Madhukumar, A. (2008). Pulse shaping functions for UWK systems. IEEE Transactions on Wireless Communications, 7(5), 1512-1516. doi:10.1109/twc.2008.061060Weling, A. S., & Heinz, T. F. (1999). Enhancement in the spectral irradiance of photoconducting terahertz emitters by chirped-pulse mixing. Journal of the Optical Society of America B, 16(9), 1455. doi:10.1364/josab.16.001455Weiner, A. M., Heritage, J. P., & Kirschner, E. M. (1988). High-resolution femtosecond pulse shaping. Journal of the Optical Society of America B, 5(8), 1563. doi:10.1364/josab.5.001563Saperstein, R. E., Alić, N., Panasenko, D., Rokitski, R., & Fainman, Y. (2005). Time-domain waveform processing by chromatic dispersion for temporal shaping of optical pulses. Journal of the Optical Society of America B, 22(11), 2427. doi:10.1364/josab.22.002427Birks, T. A., & Li, Y. W. (1992). The shape of fiber tapers. Journal of Lightwave Technology, 10(4), 432-438. doi:10.1109/50.134196Kieu, K. Q., & Mansuripur, M. (2006). Biconical Fiber Taper Sensors. IEEE Photonics Technology Letters, 18(21), 2239-2241. doi:10.1109/lpt.2006.884742Cohoon, G. (2010). Enhancing sensitivity of biconical tapered fiber sensors with multiple passes through the taper. Optical Engineering, 49(3), 034401. doi:10.1117/1.3339906Ji, W. B., Liu, H. H., Tjin, S. C., Chow, K. K., & Lim, A. (2012). Ultrahigh Sensitivity Refractive Index Sensor Based on Optical Microfiber. IEEE Photonics Technology Letters, 24(20), 1872-1874. doi:10.1109/lpt.2012.221773