Wage Shocks and the Technological Substitution of Low-wage Jobs

We extend the task-based empirical framework used in the job polarization literature to analyze the susceptibility of low-wage employment to technological substitution. We find that increases in the cost of low-wage labor, via minimum wage hikes, lead to relative employment declines at cognitively routine occupations but not manually-routine or non-routine low-wage occupations. This suggests that low-wage routine cognitive tasks are susceptible to technological substitution. While the short-run employment consequence of this reshuffling on individual workers is economically small, due to concurrent employment growth in other low-wage jobs, workers previously employed in cognitively routine jobs experience relative wage losses

Job Displacement’s Long-run Effect on Access to Employer-provided Health Insurance and Other Fringe Benefits

This paper investigates the effect of job displacement on access to employer-provided fringe benefits. We find that displacement is associated with lost access to all seven employer-provided benefits investigated. These losses increase the cost of displacement by 10% per year

TRIATHLON CYCLE-RUN TRANSITION: SEATED VERSUS ALTERNATING SEATED AND STANDING CYCLING

Nine experienced triathletes completed two trials of a cycle to run transition. During the last three minutes of a 30 minute cycling bout (at power output equal to lactate threshold) subjects either remained seated (SEAT), or alternated seated and standing cycling (30 s at a time) (ALT). Minimum and maximum knee angle and stride frequency were obtained at the end of a three minute control run (C) and at minutes 0, 2, & 4, of running after cycling transition. The only difference found by Two-Way Repeated Measures ANOVA (condition X minute) was that C was significantly different than minute 0 of the transition for stride frequency (

Welfare Rules, Incentives, and Family Structure

In this study we provide a new examination of the incentive effects of welfare rules on family structure. Focusing on the AFDC and TANF programs, we first emphasize that the literature, by and large, has assumed that the rules of those programs make a key distinction between married women and cohabiting women, but this is not a correct interpretation. In fact, it is the biological relationship between the children and any male in the household that primarily determines how the family is treated. In an empirical analysis conducted over the period 1996 to 2004 that correctly matches family structure outcomes to welfare rules, we find significant effects of several welfare policies on family structure, both work-related policies and family-oriented policies, effects that are stronger than in most past work. Many of our significant effects show that these rules led to a decrease in single motherhood and an increase in biological partnering. For all of our results, our findings indicate that the impact of welfare rules crucially hinges on the biological relationship of the male partner to the children in the household

A novel two-section tunable discrete mode Fabry-PÉrot laser exhibiting nanosecond wavelength switching

A novel widely tunable laser diode is proposed and demonstrated. Mode selection occurs by etching perturbing slots into the laser ridge. A two-section device is realized with different slot patterns in each section allowing Vernier tuning. The laser operates at 1.3 mum and achieves a maximum output power of 10 mW. A discontinuous tuning range of 30 nm was achieved with a side mode suppression greater than 30 dB. Wavelength switching times of approximately 1.5 ns between a number of wavelength channels separated by 7 nm have been demonstrated

Cost efficient narrow linewidth laser transmitter for coherent detection

Authors present a cost efficient narrow linewidth laser transmitter for future coherent detection systems. The spectral purity of the laser allows the phase modulation of data signals at bit rates as low as 155 Mb/s

Discrete mode laser diodes with ultra narrow linewidth emission <3kHz

Ex-facet, free-running ultra-low linewidth (<3 kHz), single mode laser emission is demonstrated using low cost, regrowth-free ridge waveguide discrete mode Fabry-Perot laser diode chips

Preliminary in-Situ X-Ray Absorption Fine Structure Examination of Pt/C and PtCo/C Cathode Catalysts in an Operational Polymer Electrolyte Fuel Cell

State-of-the-art polymer electrolyte fuel cells require a conditioning period to reach optimized cell performance. There is insuffi cient understanding about the behavior of catalysts during this period, especially with regard to the changing environment of the cathode electrocatalyst, which is typically Pt nanoparticles supported on high surface area Vulcan XC-72 carbon (Pt/C). The purpose of this research was to record preliminary observations of the changing environment during the conditioning phase using X-Ray Absorption Fine Structure (XAFS) spectroscopy. XAFS was recorded for a Pt/C cathode at the Pt L3-edge and a PtCo/C cathode at both the Pt L3-edge and Co K-edge. Using precision machined graphite cell-blocks, both transmission and fl uorescence data were recorded at Sector 12-BM-B of Argonne National Laboratory’s Advanced Photon Source. The fl uorescence and transmission edge steps allow for a working description of the changing electrocatalyst environment, especially water concentration, at the anode and cathode as functions of operating parameters. These features are discussed in the context of how future analysis may correlate with potential, current and changing apparent thickness of the membrane electrode assembly through loss of catalyst materials (anode, cathode, carbon support). Such direct knowledge of the effect of the conditioning protocol on the electrocatalyst may lead to better catalyst design. In turn, this may lead to minimizing, or even eliminating, the conditioning period

Comparison of frequency symmetric signal generation from a BPSK input using fiber and semiconductor-based nonlinear elements

This letter compares two nonlinear media for simultaneous carrier recovery and generation of frequency symmetric signals from a 42.7-Gb/s nonreturn-to-zero binary phase-shift-keyed input by exploiting four-wave mixing in a semiconductor optical amplifier and a highly nonlinear optical fiber for use in a phase-sensitive amplifier