331 research outputs found
KOI-1003: A new spotted, eclipsing RS CVn binary in the Kepler field
Using the high-precision photometry from the Kepler space telescope,
thousands of stars with stellar and planetary companions have been observed.
The characterization of stars with companions is not always straightforward and
can be contaminated by systematic and stellar influences on the light curves.
Here, through a detailed analysis of starspots and eclipses, we identify
KOI-1003 as a new, active RS CVn star---the first identified with data from
Kepler. The Kepler light curve of this close binary system exhibits the
system's primary transit, secondary eclipse, and starspot evolution of two
persistent active longitudes. The near equality of the system's orbital and
rotation periods indicates the orbit and primary star's rotation are nearly
synchronized ( days; days). By assuming the secondary star is on the main sequence, we suggest
the system consists of a subgiant primary and
a main-sequence companion. Our work gives a
distance of pc and an age of Gyr,
parameters which are discrepant with previous studies that included the star as
a member of the open cluster NGC 6791.Comment: 21 pages, 19 figures, accepted to Ap
Predicting U.S. Jet Fighter Aircraft Introductions from 1944 to 1982: A Dogfight Between Regression and TFDEA
Since its inception in 2001, technology forecasting using data envelopment analysis (TFDEA) has been used with a number of applications. This paper presents a formal comparison of TFDEA to a previously published application from Technological Forecasting and Social Change by Joseph Martino. Using the data and Martino’s multiple regression model, we compare results obtained from TFDEA to those previously published. Both techniques predict the first flights of fighter jets introduced between 1960 and 1982 by using the first flights of aircraft introduced between 1944 and 1960. TFDEA was found to better predict the first flight dates than the forecast using multiple regression. These results indicate that TFDEA may be a powerful new technique for predicting complex technological trends and time to market for new products
Improving Time to Market Forecasts: A Comparison of Two Technology Forecasting Techniques for Predicting U.S. Fighter Jet Introductions From 1944 to 1982
Since its origin in 2001, technology forecasting using data envelopment analysis (TFDEA) has been tested with a number of applications. This paper uses a previously published technology forecast comparison of U.S. fighter jets between the years 1944 and 1982 to compare TFDEA to basic regression. Both techniques use aircraft introduced between 1944 and 1960 to predict the first flights of those fighters introduced between 1960 and 1982. TFDEA was found to better predict the first flight dates than the forecast using regression. These results indicate that TFDEA may be a powerful new technique for predicting complex technological trends and time to market for new product
Exploration of Adoption of Service Innovations Through Technology Road-Mapping: Case of Location Based Services
Exploration of Adoption of Service Innovations through Technology Road-Mapping: Case of Location Based Services: 10.4018/jssmet.2010040105: This paper utilizes a technology road-mapping approach to demonstrate how a traditional technology management process can be applied to improve plannin
Activity of comet 103P/Hartley 2 at the time of the EPOXI mission fly-by
Comet 103P/Hartley~2 was observed on Nov. 1-6, 2010, coinciding with the
fly-by of the space probe EPOXI. The goal was to connect the large scale
phenomena observed from the ground, with those at small scale observed from the
spacecraft. The comet showed strong activity correlated with the rotation of
its nucleus, also observed by the spacecraft. We report here the
characterization of the solid component produced by this activity, via
observations of the emission in two spectral regions where only grain
scattering of the solar radiation is present. We show that the grains produced
by this activity had a lifetime of the order of 5 hours, compatible with the
spacecraft observations of the large icy chunks. Moreover, the grains produced
by one of the active regions have a very red color. This suggests an organic
component mixed with the ice in the grains.Comment: 11 pages, 7 figures, Icarus in pres
Real-world outcomes of sipuleucel-T treatment in PROCEED, a prospective registry of men with metastatic castration-resistant prostate cancer.
BackgroundThe large registry, PROVENGE Registry for the Observation, Collection, and Evaluation of Experience Data (PROCEED)(NCT01306890), evaluated sipuleucel-T immunotherapy for asymptomatic/minimally symptomatic metastatic castration-resistant prostate cancer (mCRPC).MethodsPROCEED enrolled patients with mCRPC receiving 3 biweekly sipuleucel-T infusions. Assessments included overall survival (OS), serious adverse events (SAEs), cerebrovascular events (CVEs), and anticancer interventions (ACIs). Follow-up was for ≥3 years or until death or study withdrawal.ResultsIn 2011-2017, 1976 patients were followed for 46.6 months (median). The median age was 72 years, and the baseline median prostate-specific antigen level was 15.0 ng/mL; 86.7% were white, and 11.6% were African American. Among the patients, 1902 had 1 or more sipuleucel-T infusions. The median OS was 30.7 months (95% confidence interval [CI], 28.6-32.2 months). Known prognostic factors were independently associated with OS in a multivariable analysis. Among the 1255 patients who died, 964 (76.8%) died of prostate cancer (PC) progression. The median time from the first infusion to PC death was 42.7 months (95% CI, 39.4-46.2 months). The incidence of sipuleucel-T-related SAEs was 3.9%. The incidence of CVEs was 2.8%, and the rate per 100 person-years was 1.2 (95% CI, 0.9-1.6). The CVE incidence among 11,972 patients with mCRPC from the Surveillance, Epidemiology, and End Results-Medicare database was 2.8%; the rate per 100 person-years was 1.5 (95% CI, 1.4-1.7). One or more ACIs (abiraterone, enzalutamide, docetaxel, cabazitaxel, or radium 223) were received by 77.1% of the patients after sipuleucel-T; 32.5% and 17.4% of the patients experienced 1- and 2-year treatment-free intervals, respectively.ConclusionsPROCEED provides contemporary survival data for sipuleucel-T-treated men in a real-world setting of new life-prolonging agents, which will be useful in discussing treatment options with patients and in powering future trials with sipuleucel-T. The safety and tolerability of sipuleucel-T in PROCEED were consistent with previous findings
Three years of Fermi GBM Earth Occultation Monitoring: Observations of Hard X-ray/Soft Gamma-Ray Sources
The Gamma ray Burst Monitor (GBM) on board Fermi has been providing
continuous data to the astronomical community since 2008 August 12. In this
paper we present the results of the analysis of the first three years of these
continuous data using the Earth occultation technique to monitor a catalog of
209 sources. From this catalog, we detect 99 sources, including 40 low-mass
X-ray binary/neutron star systems, 31 high-mass X-ray binary neutron star
systems, 12 black hole binaries, 12 active galaxies, 2 other sources, plus the
Crab Nebula, and the Sun. Nine of these sources are detected in the 100-300 keV
band, including seven black-hole binaries, the active galaxy Cen A, and the
Crab. The Crab and Cyg X-1 are also detected in the 300-500 keV band. GBM
provides complementary data to other sky-monitors below 100 keV and is the only
all-sky monitor above 100 keV. Up-to-date light curves for all of the catalog
sources can be found at http://heastro.phys.lsu.edu/gbm/.Comment: 24 pages, 12 figures, accepted for publication in ApJ
EXPRES. II. Searching for Planets Around Active Stars: A Case Study of HD 101501
By controlling instrumental errors to below 10 cm/s, the EXtreme PREcision
Spectrograph (EXPRES) allows for a more insightful study of photospheric
velocities that can mask weak Keplerian signals. Gaussian Processes (GP) have
become a standard tool for modeling correlated noise in radial velocity
datasets. While GPs are constrained and motivated by physical properties of the
star, in some cases they are still flexible enough to absorb unresolved
Keplerian signals. We apply GP regression to EXPRES radial velocity
measurements of the 3.5 Gyr old chromospherically active Sun-like star, HD
101501. We obtain tight constraints on the stellar rotation period and the
evolution of spot distributions using 28 seasons of ground-based photometry, as
well as recent data. Light curve inversion was carried out on both
photometry datasets to reveal the spot distribution and spot evolution
timescales on the star. We find that the m/s rms radial velocity
variations in HD 101501 are well-modeled with a GP stellar activity model
without planets, yielding a residual rms scatter of 45 cm/s. We carry out
simulations, injecting and recovering signals with the GP framework, to
demonstrate that high-cadence observations are required to use GPs most
efficiently to detect low-mass planets around active stars like HD 101501.
Sparse sampling prevents GPs from learning the correlated noise structure and
can allow it to absorb prospective Keplerian signals. We quantify the moderate
to high-cadence monitoring that provides the necessary information to
disentangle photospheric features using GPs and to detect planets around active
stars.Comment: 25 pages, 16 figures, accepted to A
Emerging Digital Frontiers for Service Innovation
This paper examines emerging digital frontiers for service innovation that a panel discussed at a workshop on this topic held at the 48th Annual Hawaii International Conference on System Sciences (HICSS). The speakers and participants agreed that that service systems are fundamental for service innovation and value creation. In this context, service systems are related to cognitive systems, smart service systems, and cyber-physical systems and depend on the interconnectedness among system components. The speakers and participants regarded humans as the central entity in all service systems. In addition, data, they saw personal data in particular as key to service systems. They also identified several challenges in the areas of cognitive systems, smart service systems, cyber-physical systems, and human-centered service systems. We hope this workshop report helps in some small way to cultivate the emerging service science discipline and to nurture fruitful discussions on service innovation
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