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Human resource management in India: strategy, performance and complementarity
This study seeks to explore which types of HR practice are associated with better organisational performance (OP). Whilst the core finding—that specific HR practices lead to better organisational outcomes may not be surprising—we also found an absence of complementarity. Normally, the absence of complementarities would suggest limitations in institutional supports; on the one hand, however, institutional shortfalls are not unique to India and may be encountered in many emerging market settings. In contrast, the great internal diversity of the Indian setting, with strong variations recognised amongst institutions, along with enforcement capabilities, might suggest that these tendencies are particularly pronounced. We also found a strong link between the intrinsic rewards and performance—an unexpected result in a low-income country, where wages are generally low. We suggest that this may reflect the nature of the labour market and the limited (and possibly proportionately shrinking) pool of good jobs, making exit a difficult option for all but the best qualified. Whilst this puts employees in a poor bargaining position in bidding-up pay (making pay rises seem unfeasible), the intrinsic attributes of the job become more important
A Blockchain-based Approach for Data Accountability and Provenance Tracking
The recent approval of the General Data Protection Regulation (GDPR) imposes
new data protection requirements on data controllers and processors with
respect to the processing of European Union (EU) residents' data. These
requirements consist of a single set of rules that have binding legal status
and should be enforced in all EU member states. In light of these requirements,
we propose in this paper the use of a blockchain-based approach to support data
accountability and provenance tracking. Our approach relies on the use of
publicly auditable contracts deployed in a blockchain that increase the
transparency with respect to the access and usage of data. We identify and
discuss three different models for our approach with different granularity and
scalability requirements where contracts can be used to encode data usage
policies and provenance tracking information in a privacy-friendly way. From
these three models we designed, implemented, and evaluated a model where
contracts are deployed by data subjects for each data controller, and a model
where subjects join contracts deployed by data controllers in case they accept
the data handling conditions. Our implementations show in practice the
feasibility and limitations of contracts for the purposes identified in this
paper
B-field Determination from Magnetoacoustic Oscillations in kHz QPO Neutron Star Binaries: Theory and Observations
We present a method for determining the B-field around neutron stars based on
observed kHz and viscous QPO frequencies used in combination with the best-fit
optical depth and temperature of a Comptonization model. In the framework of
the transition layer QPO model, we analyze magnetoacoustic wave formation in
the layer between a neutron star surface and the inner edge of a Keplerian
disk. We derive formulas for the magnetoacoustic wave frequencies for different
regimes of radial transition layer oscillations. We demonstrate that our model
can use the QPO as a new kind of probe to determine the magnetic field
strengths for 4U 1728-42, GX 340+0, and Sco X-1 in the zone where the QPOs
occur. Observations indicate that the dependence of the viscous frequency on
the Keplerian frequency is closely related to the inferred dependence of the
magnetoacoustic wave frequency on the Keplerian frequency for a dipole magnetic
field. The magnetoacoustic wave dependence is based on a single parameter, the
magnetic moment of the star as estimated from the field strength in the
transition layer. The best-fit magnetic moment parameter is about (0.5-1)x
10^{25} G cm^3 for all studied sources. From observational data, the magnetic
fields within distances less 20 km from neutron star for all three sources are
strongly constrained to be dipole fields with the strengths 10^{7-8} G on the
neutron star surface.Comment: 10 pages, 1 figure, accepted for the Astrophysical Journal Letter
Study and prototype of data system interactions for the Earth Observing System Data and Information System
A crucial part of the Earth Observing System (EOS) is its Data and Information System (EOSDIS). The success of EOS depends not only on its instruments and science studies, but also on its ability to help scientists integrate data sets of geophysical and biological measurements taken by various instruments and investigators. NASA contractors have completed Phase B studies of EOSDIS, in particular its architecture, functionality, and user interfacing. At this point in time, it may seem impossible to exercise the EOSDIS or any of its components since they do not exist; i.e., if the EOSDIS is accepted as a totally new system, distinct from any existing DIS. However, if EOSDIS is seen as evolving from existing data systems, then some limited prototyping studies can be conducted by using currently functioning systems. In support of both the EOSDIS Science Advisory Panel and the EOSDIS Project, a prototyping activity was carried out by a cross section of interdisciplinary scientists. That prototyping activity is summarized and some conclusions are drawn that can be used by NASA-Goddard to evaluate and modify the specifications soon to be released in an RFP to build EOSDIS
LAWS simulation: Sampling strategies and wind computation algorithms
In general, work has continued on developing and evaluating algorithms designed to manage the Laser Atmospheric Wind Sounder (LAWS) lidar pulses and to compute the horizontal wind vectors from the line-of-sight (LOS) measurements. These efforts fall into three categories: Improvements to the shot management and multi-pair algorithms (SMA/MPA); observing system simulation experiments; and ground-based simulations of LAWS
The asteroseismological potential of the pulsating DB white dwarf stars CBS 114 and PG 1456+103
We have acquired 65 h of single-site time-resolved CCD photometry of the
pulsating DB white dwarf star CBS 114 and 62 h of two-site high-speed CCD
photometry of another DBV, PG 1456+103. The pulsation spectrum of PG 1456+103
is complicated and variable on time scales of about one week and could only
partly be deciphered with our measurements. The modes of CBS 114 are more
stable in time and we were able to arrive at a frequency solution somewhat
affected by aliasing, but still satisfactory, involving seven independent modes
and two combination frequencies. These frequencies also explain the discovery
data of the star, taken 13 years earlier. We find a mean period spacing of 37.1
+/- 0.7 s significant at the 98% level between the independent modes of CBS 114
and argue that they are due to nonradial g-mode pulsations of spherical degree
l=1. We performed a global search for asteroseismological models of CBS 114
using a genetic algorithm, and we examined the susceptibility of the results to
the uncertainties of the observational frequency determinations and mode
identifications (we could not provide m values). The families of possible
solutions are identified correctly even without knowledge of m. Our optimal
model suggests Teff = 21,000 K and M_* = 0.730 M_sun as well as log(M_He/M_*) =
-6.66, X_O = 0.61. This measurement of the central oxygen mass fraction implies
a rate for the ^12C(alpha,gamma)^16O nuclear reaction near S_300=180 keV b,
consistent with laboratory measurements.Comment: 10 pages, 10 embedded figures, 3 embedded tables. Accepted for
publication in MNRA
Proof of Luck: an Efficient Blockchain Consensus Protocol
In the paper, we present designs for multiple blockchain consensus primitives
and a novel blockchain system, all based on the use of trusted execution
environments (TEEs), such as Intel SGX-enabled CPUs. First, we show how using
TEEs for existing proof of work schemes can make mining equitably distributed
by preventing the use of ASICs. Next, we extend the design with proof of time
and proof of ownership consensus primitives to make mining energy- and
time-efficient. Further improving on these designs, we present a blockchain
using a proof of luck consensus protocol. Our proof of luck blockchain uses a
TEE platform's random number generation to choose a consensus leader, which
offers low-latency transaction validation, deterministic confirmation time,
negligible energy consumption, and equitably distributed mining. Lastly, we
discuss a potential protection against up to a constant number of compromised
TEEs.Comment: SysTEX '16, December 12-16, 2016, Trento, Ital
Environmental protection of titanium alloys at high temperatures
Various concepts were evaluated for protecting titanium alloys from oxygen contamination at 922 K (1200 F) and from hot-salt stress-corrosion at 755 K (900 F). It is indicated that oxygen-contamination resistance can be provided by a number of systems, but for hot-salt stress-corrosion resistance, factors such as coating integrity become very important. Titanium aluminides resist oxygen ingress at 922 K through the formation of alumina (on TiAl3) or modified TiO2 (on Ti3Al, TiAl) scales. TiAl has some resistance to attack by hot salt, but has limited ductility. Ductile Ti-Ni and Ti-Nb-Cr-Al alloys provide limited resistance to oxygen ingress, but are not greatly susceptible to hot-salt stress-corrosion cracking
Infrared emission from ultracompact H II regions
Models of circumstellar dust shells around ultracompact (UC) H II regions were constructed that accurately fit the observed IR flux distributions. The models assume spherically symmetric dust shells illuminated by stars whose bolometric luminosity is inferred from the integrated FIR flux densities. Assuming ionization by a single zero age main sequence (ZAMS) star, the relations of Panagia were used to infer the stellar radius and effective temperature for a given luminosity. The grain mixture in the dust shell consists of bare graphite and silicate grains with the optical properties of Draine and Lee and the size distribution of Mathis et al. The computer code of Wolfire et al was used to solve the radiative transfer equations through a spherical dust shell. The model provides monochromatic luminosities, dust temperatures, and opacities through the shell. Aside from the stellar and dust properties, the only other input parameters to the model are the distance to the shell, the form of its density distribution, and its outer radius. Predictions of the model are compared with observations of a typical UC H II region and the run of dust temperature with radius and the optical depth with frequency are discussed
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