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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 “battlespace” 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 conflict’s prescriptive norms governing the “conduct of hostilities.” 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
The macroeconomics of subsistence points
This paper explores the macroeconomic consequences of preferences displaying a subsistence point. It departs from the existing related literature by assuming that subsistence points are specific to each variety of goods rather than to the composite consumption good. We show that this simple feature makes the price elasticity of demand for individual goods procyclical. As a result, markups behave countercyclically in equilibrium. This implication is in line with the available empirical evidence
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
Modelling the Spatial Structure of Pig Production in Denmark
In Denmark, the concentration of pig production is highest in the western part of the country. However, there may be even larger local differences in the number of pigs produced. In this study we analyze the determinants of the location of pig production in Denmark with particular focus on spatial externalities and the interaction between the location of pig production and upstream sector and slaughterhouses. It is the assumption that the location of slaughterhouses is influenced by the location of the primary producers, implying that this variable is endogenous, whereas the location of primary producers is independent of the location of slaughterhouses. This is due to the fact that transportation costs of pigs are paid by the cooperatives owning the slaughterhouses. This assumption is tested applying a spatial econometric model. The model is estimated for 1999 and 2004. Furthermore, the impact of negative environmental externalities of pig production on location is analyzed. The results show that spatial externalities have a positive effect on the location of pig production whereas environmental regulation has a negative effect on location.Agglomeration, Externalities, Spatial Econometrics, Polluted Production, Livestock Production/Industries,
Spot evolution in the eclipsing binary CoRoT 105895502
Stellar activity is ubiquitous in late-type stars. The special geometry of
eclipsing binary systems is particularly advantageous to study the stellar
surfaces and activity. We present a detailed study of the 145 d CoRoT light
curve of the short-period eclipsing binary CoRoT 105895502. By means of
light-curve modeling with Nightfall, we determine the orbital period, effective
temperature, Roche-lobe filling factors, mass ratio, and orbital inclination of
CoRoT 105895502 and analyze the temporal behavior of starspots in the system.
Our analysis shows one comparably short-lived (about 40 d) starspot, remaining
quasi-stationary in the binary frame, and one starspot showing prograde motion
at a rate of 2.3 deg per day, whose lifetime exceeds the duration of the
observation. In the CoRoT band, starspots account for as much as 0.6 % of the
quadrature flux of CoRoT 105895502, however we cannot attribute the spots to
individual binary components with certainty. Our findings can be explained by
differential rotation, asynchronous stellar rotation, or systematic spot
evolution.Comment: Accepted in A&
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