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"Out of the loop": autonomous weapon systems and the law of armed conflict
The introduction of autonomous weapon systems into the âbattlespaceâ will profoundly influence the nature of future warfare. This reality has begun to draw the attention of the international legal community, with increasing calls for an outright ban on the use of autonomous weapons systems in armed conflict. This Article is intended to help infuse granularity and precision into the legal debates surrounding such weapon systems and their future uses. It suggests that whereas some conceivable autonomous weapon systems might be prohibited as a matter of law, the use of others will be unlawful only when employed in a manner that runs contrary to the law of armed conflictâs prescriptive norms governing the âconduct of hostilities.â This Article concludes that an outright ban of autonomous weapon systems is insupportable as a matter of law, policy, and operational good sense. Indeed, proponents of a ban underestimate the extent to which the law of armed conflict, including its customary law aspect, will control autonomous weapon system operations. Some autonomous weapon systems that might be developed would already be unlawful per se under existing customary law, irrespective of any treaty ban. The use of certain others would be severely limited by that law.
Furthermore, an outright ban is premature since no such weapons have even left the drawing board. Critics typically either fail to take account of likely developments in autonomous weapon systems technology or base their analysis on unfounded assumptions about the nature of the systems. From a national security perspective, passing on the opportunity to develop these systems before they are fully understood would be irresponsible. Perhaps even more troubling is the prospect that banning autonomous weapon systems altogether based on speculation as to their future form could forfeit their potential use in a manner that would minimize harm to civilians and civilian objects when compared to non-autonomous weapon systems
Field testing of strategies for fire blight control in organic fruit growing
In organic fruit growing effective control strategies are needed to prevent blossom infections by the fire blight pathogen Erwinia amylovora. Many potential control agents are under discussion and have been tested in vitro and in vivo. 19 out of 27 tested preparations showed a high efficacy against E. amylovora in vitro. Nevertheless, on detached apple blossoms only 7 of them led to a symptom reduction by more than 50%. In six field trials conducted according to the EPPO guideline PP1/166(3) BlossomProtect (82%), Myco-sin (65%) and Funguran (58%) had the highest efficiency. In 2006 and 2007, strategies to integrate BlossomProtect in spray schedules of organic apple production have been tested. The use of sulphur or lime-sulphur before or after BlossomProtect did not influence the efficiency of BlossomProtect, which showed that fire blight control is possible without compromising apple scab control. The addition of Cutisan to BlossomProtect reduced fruit russet. An alternating use of BlossomProtect and Myco-sin was shown to be possible
Incomplete cost pass-through under deep habits
A number of empirical studies document that marginal cost shocks are not fully passed through to prices at the firm level and that prices are substantially less volatile than costs. We show that in the relative-deep-habits model of Ravn, Schmitt-Grohe, and Uribe (2006), firm-specific marginal cost shocks are not fully passed through to product prices. That is, in response to a firm-specific increase in marginal costs, prices rise, but by less than marginal costs leading to a decline in the firm-specific markup of prices over marginal costs. Pass-through is predicted to be even lower when shocks to marginal costs are anticipated by firms. In our model, unanticipated firm-specific cost shocks lead to incomplete pass-through (or a decline in markups) of about 20 percent and anticipated cost shocks are associated with incomplete pass-through of about 50 percent. The model predicts that cost pass-through is increasing in the persistence of marginal cost shocks and U-shaped in the strength of habits. The relative-deep-habits model implies that conditional on marginal cost disturbances, prices are less volatile than marginal costs
X-ray activity cycle on the active ultra-fast rotator AB Dor A? Implication of correlated coronal and photometric variability
Although chromospheric activity cycles have been studied in a larger number
of late-type stars for quite some time, very little is known about coronal
activity-cycles in other stars and their similarities or dissimilarities with
the solar activity cycle. While it is usually assumed that cyclic activity is
present only in stars of low to moderate activity, we investigate whether the
ultra-fast rotator AB Dor, a K dwarf exhibiting signs of substantial magnetic
activity in essentially all wavelength bands, exhibits a X-ray activity cycle
in analogy to its photospheric activity cycle of about 17 years and possible
correlations between these bands. We analysed the combined optical photometric
data of AB Dor A, which span ~35 years. Additionally, we used ROSAT and
XMM-Newton X-ray observations of AB Dor A to study the long-term evolution of
magnetic activity in this active K dwarf over nearly three decades and searched
for X-ray activity cycles and related photometric brightness changes. AB Dor A
exhibits photometric brightness variations ranging between 6.75 < Vmag < 7.15
while the X-ray luminosities range between 29.8 < log LX [erg/s] < 30.2 in the
0.3-2.5 keV. As a very active star, AB Dor A shows frequent X-ray flaring, but,
in the long XMM-Newton observations a kind of basal state is attained very
often. This basal state probably varies with the photospheric activity-cycle of
AB Dor A which has a period of ~17 years, but, the X-ray variability amounts at
most to a factor of ~2, which is, much lower than the typical cycle amplitudes
found on the Sun.Comment: 10 page
A centrifugo-magnetically actuated gas micropump
This paper describes a novel gas micropump on a centrifugal microfluidic platform. The pump is integrated on a passive and microstructured polymer disk which is sealed with an elastomer lid featuring paramagnetic inlays. The rotational motion of this hybrid disk over a stationary magnet induces a designated sequence of volume displacements of the elastic lid, leading to a net transport of gas. The pumping pressure scales linearly with the frequency, with a maximum observable pressure of 4.1 kPa. The first application of this rotary device is the production of gas-liquid flows by pumping ambient air into a continuous centrifugal flow of liquid. The injected gas volume segments the liquid stream into a series of liquid compartments. Apart from such multi-phase flows, the new pumping technique supplements a generic air-to-liquid sampling method to centrifugal microfluidic platforms
Unitarization of monodromy representations and constant mean curvature trinoids in 3-dimensional space forms
We present a theorem on the unitarizability of loop group valued monodromy
representations and apply this to show the existence of new families of
constant mean curvature surfaces homeomorphic to a thrice-punctured sphere in
the simply-connected 3-dimensional space forms , \bbS^3 and \bbH^3.
Additionally, we compute the extended frame for any associated family of
Delaunay surfaces.Comment: 18 pages, revised versio
A posteriori noise estimation in variable data sets
Most physical data sets contain a stochastic contribution produced by
measurement noise or other random sources along with the signal. Usually,
neither the signal nor the noise are accurately known prior to the measurement
so that both have to be estimated a posteriori. We have studied a procedure to
estimate the standard deviation of the stochastic contribution assuming
normality and independence, requiring a sufficiently well-sampled data set to
yield reliable results. This procedure is based on estimating the standard
deviation in a sample of weighted sums of arbitrarily sampled data points and
is identical to the so-called DER_SNR algorithm for specific parameter
settings. To demonstrate the applicability of our procedure, we present
applications to synthetic data, high-resolution spectra, and a large sample of
space-based light curves and, finally, give guidelines to apply the procedure
in situation not explicitly considered here to promote its adoption in data
analysis.Comment: Accepted for publication in A&
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