72,557 research outputs found
Outsourcing and Skill Imports: Foreign High-Skilled Workers on H-1B and L-1 Visas in the United States
No full textThis working paper looks in detail at the H-1B and L-1 visa programs for temporary employment in the United States. Based on official data from the US Citizenship and Immigration Services and the US Department of State, H-1B and L-1 visa issuance rapidly increased in the late 1990s, followed by a marked slowdown after 2001. This points to the highly cyclical nature of both visa programs. Indian nationals and immigrants working in computer-related occupations dominate the H1-B and L-1 population in the United States, but these two groups are also found to be the most cyclical segment, with very large declines in inflows after 2001. The total population of H-1B visaholders in 2003 is estimated to range between 387,000 and 746,000, of which 160,000 to 306,000 were Indian nationals. As all data on H-1B/L-1 visaholders are gross numbers and gross jobs data for comparable categories are absent, the extent of the impact of these visa programs on the US labor market cannot be gauged precisely. A broad range of US industries and educational institutions are found to be employing H-1B recipients, with the IT industry being the dominant sector. Evidence of aggressive wage-cost cutting, including paying H-1B recipients only the legally mandated 95 percent of the prevailing US wage, is found among some H-1B employers, although no systematic abuse of the system is present.Outsourcing, offshoring, high-skilled labor, immigration, H1B/L-1 visas
Letter from H. L. Russell to Carl Hayden
No full textLetter from H. L. Russell to Carl Hayden regarding fines in the park
Multiuser MIMO-OFDM for Next-Generation Wireless Systems
No full textThis overview portrays the 40-year evolution of orthogonal frequency division multiplexing (OFDM) research. The amelioration of powerful multicarrier OFDM arrangements with multiple-input multiple-output (MIMO) systems has numerous benefits, which are detailed in this treatise. We continue by highlighting the limitations of conventional detection and channel estimation techniques designed for multiuser MIMO OFDM systems in the so-called rank-deficient scenarios, where the number of users supported or the number of transmit antennas employed exceeds the number of receiver antennas. This is often encountered in practice, unless we limit the number of users granted access in the base station’s or radio port’s coverage area. Following a historical perspective on the associated design problems and their state-of-the-art solutions, the second half of this treatise details a range of classic multiuser detectors (MUDs) designed for MIMO-OFDM systems and characterizes their achievable performance. A further section aims for identifying novel cutting-edge genetic algorithm (GA)-aided detector solutions, which have found numerous applications in wireless communications in recent years. In an effort to stimulate the cross pollination of ideas across the machine learning, optimization, signal processing, and wireless communications research communities, we will review the broadly applicable principles of various GA-assisted optimization techniques, which were recently proposed also for employment inmultiuser MIMO OFDM. In order to stimulate new research, we demonstrate that the family of GA-aided MUDs is capable of achieving a near-optimum performance at the cost of a significantly lower computational complexity than that imposed by their optimum maximum-likelihood (ML) MUD aided counterparts. The paper is concluded by outlining a range of future research options that may find their way into next-generation wireless systems
Letter from Carl Hayden to L. H. Mcellherren
No full textLetter from Carl Hayden to L. H. McEllherren detailing the funeral of Hon. M. P. Kinkaid, Chairman of the Committee on Irrigation of Arid Lands as well as Hayden's travel plans for the summer
Forecast of July 2015—New Jersey: prospects for the long term
No full textThe July 2015 R/ECON forecast shows more rapid growth for the state in 2015 than in 2014. Nonagricultural employment rose by 0.7 percent—or 27,700 jobs in 2014—after growth of 1.2 percent or 45,100 jobs in 2013. Growth will improve to 1.1 percent in 2015 and 2016 and then average 0.8 percent over the rest of the forecast period, which goes through 2045. At these rates the job base will return to the peak level reached in the first quarter of 2008 in mid-2017. By the end of the forecast period in 2045 the employment base will be nearly a million jobs, and 23 percent, greater than its level at the peak.1 These projections assume no specific recession/recovery cycle disrupts the state’s or nation’s growth. Although this seems rather far-fetched given that the average business cycle (peak to peak) in the U.S. since World War II has lasted about 24 quarters and the current cycle is now in its seventh year, a caveat to keep in mind is that this is a long term TREND forecast; it does not purport to indicate at what point(s) CYCLES may occur.Rutgers Economic Advisory Service (R/ECON) quarterly repor
Inheritance of apetalous flowers in a mutant of oilseed rape
No full textOilseed rape (Brassica napus L.) genotypes with reduced petal size are thought to have advantages in photosynthetic capacity and in disease resistance. This study was conducted to analyze the inheritance of a completely apetalous mutant that was induced by mutagenic treatment. The mutant ap-Tengbe was crossed with the German winter rapeseed cultivar Falcon. The F-1, the F-2, and both backcrosses including reciprocal generations were grown in field experiments at Gottingen, Germany, in 1997-1998 and at Hangzhou, China, in 1998-1999. The apetalous character of ap-Tengbe is regulated by an interaction of cytoplasmic genes and two pairs of nuclear genes. Completely apetalous flowers are only expressed in genotypes with the ap cytoplasm and two homozygous recessive genes. In conclusion, the mutant ap-Tengbe is useful to produce completely apetalous genotypes, but cytoplasmic effects have to be considered
Hybrid Iterative Multiuser Detection for Channel Coded Space Division Multiple Access OFDM Systems
No full textSpace division multiple access (SDMA) aided orthogonal frequency division multiplexing (OFDM) systems assisted by efficient multiuser detection (MUD) techniques have recently attracted intensive research interests. The maximum likelihood detection (MLD) arrangement was found to attain the best performance, although this was achieved at the cost of a computational complexity, which increases exponentially both with the number of users and with the number of bits per symbol transmitted by higher order modulation schemes. By contrast, the minimum mean-square error (MMSE) SDMA-MUD exhibits a lower complexity at the cost of a performance loss. Forward error correction (FEC) schemes such as, for example, turbo trellis coded modulation (TTCM), may be efficiently combined with SDMA-OFDM systems for the sake of improving the achievable performance. Genetic algorithm (GA) based multiuser detection techniques have been shown to provide a good performance in MUD-aided code division multiple access (CDMA) systems. In this contribution, a GA-aided MMSE MUD is proposed for employment in a TTCM assisted SDMA-OFDM system, which is capable of achieving a similar performance to that attained by its optimum MLD-aided counterpart at a significantly lower complexity, especially at high user loads. Moreover, when the proposed biased Q-function based mutation (BQM) assisted iterative GA (IGA) MUD is employed, the GA-aided system’s performance can be further improved, for example, by reducing the bit error ratio (BER) measured at 3 dB by about five orders of magnitude in comparison to the TTCM assisted MMSE-SDMA-OFDM benchmarker system, while still maintaining modest complexity
Environmental effects on expression of apetalous flowers in oilseed rape
No full textApetalous genotypes may be of interest in oilseed rape breeding because of a more efficient photosynthesis and a lower susceptivity to pathogens infecting the petals. Petalous degree was, however, found unstable during flowering. Two types of environmental effects were investigated: (1) developmental stage of the flowers, and (2) application of different phytohormones. Materials used were (1) Fl, BC1, and F2 generations developed from crosses between the German cultivar 'Falcon' and the apetalous mutant 'ap-Tengbe', and (2) double haploid (DH) lines with apetalous, partial apetalous and normal petalled flowers developed by microspore culture of F1 plants ('ap-Renard' x 'ap-Tengbe'). it was observed (1) that petalous degree (PDgr) decreased from initial anthesis to end of flowering both in the partial apetalous and the normal petalled plants originating from the cross between 'Falcon' and 'ap-Tengbe'; and (2) that the supply of auxins or cytokinins resulted in reduction of PDgr in the partial or the normal petalled DH plants. The results suggest that the unstable expression of PDgr was caused by endogenetie accumulation of auxins or/and cytokinins at later flowering stages
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