1,539 research outputs found
Providing Corrective Feedback During Retrieval Practice Does Not Increase Retrieval-Induced Forgetting
Recalling a subset of studied materials can impair subsequent retrieval of related, nontested materials. In two experiments, we examined the influence of providing corrective feedback (no feedback, immediate feedback, delayed feedback) during retrieval practice on this retrieval-induced forgetting effect. Performance was assessed with category cued recall (e.g., recall all exemplars studied under Weather), category-and-stem cued recall (e.g., Weather–B___), and recognition. We report a dissociation between the effects of feedback on memory of the tested materials and the nontested materials. Whereas providing immediate or delayed feedback (compared to no feedback) improved recall and recognition of the tested items, it had no influence on retrieval-induced forgetting. These results are consistent with the inhibition account of retrieval-induced forgetting. From an applied perspective, this finding is encouraging for students and educators who use testing to foster learning
Assessing Regulatory Impact Analyses: The Failure of Agencies to Comply With Executive Order 12,866
None.Environment, Health and Safety, Regulatory Reform
Assessing the Quality of Regulatory Impact Analyses
This study provides the most comprehensive evaluation of the quality of recent economic analyses that agencies conduct before finalizing major regulations. We construct a new dataset that includes analyses of forty-eight major health, safety, and environmental regulations from mid-1996 to mid-1999. This dataset provides detailed information on a variety of issues, including an agency's treatment of benefits, costs, net benefits, discounting, and uncertainty. We use this dataset to assess the quality of recent economic analyses and to determine the extent to which they are consistent with President Clinton's Executive Order 12866 and the benefit-cost guidelines issued by the Office of Management and Budget (OMB). We find that economic analyses prepared by regulatory agencies typically do not provide enough information to make decisions that will maximize the efficiency or effectiveness of a rule. Agencies quantified net benefits for only 29 percent of the rules. Agencies failed to discuss alternatives in 27 percent of the rules and quantified costs and benefits of alternatives in only 31 percent of the rules. Our findings strongly suggest that agencies generally failed to comply with the executive order and adhere to the OMB guidelines. We offer specific suggestions for improving the quality of analysis and the transparency of the regulatory process, including writing clear executive summaries, making analyses available on the Internet, providing more careful consideration of alternatives to a regulation, and estimating net benefits of a regulation when data on costs and benefits are provided.
How is Death Penalty Used in China?
Strike hard Campaigns. The Views of the People and of the Elite. Comments on the interplay between penal populism, leadership from the front and human rights. To what extent are hard strike campaigns formed as penal populism in the provinces or as a result of leadership from the front centrally. The hard strike campaigns in the future. (Preliminary Symposium Program for The first Oslo international Symposium on Death penalty in Asia)published_or_final_versio
A New Large Super-Fast Rotator: (335433) 2005 UW163
Asteroids of size larger than 150 m generally do not have rotation periods
smaller than 2.2 hours. This spin cutoff is believed to be due to the
gravitationally bound rubble-pile structures of the asteroids. Rotation with
periods exceeding this critical value will cause asteroid breakup. Up until
now, only one object, 2001 OE84, has been found to be an exception to this spin
cutoff. We report the discovery of a new super-fast rotator, (335433) 2005
UW163, spinning with a period of 1.290 hours and a lightcurve variation of
mag from the observations made at the P48 telescope and the P200
telescope of the Palomar Observatory. Its mag and
multi-band colors (i.e., mag, mag
and SDSS mag) show it is a V-type asteroid with a diameter of
km. This indicates (335433) 2005 UW163 is a super-fast rotator
beyond the regime of the small monolithic asteroid.Comment: 18 pages, 4 figures, 1 table Accepted by ApJ
The SnoDog: Preliminary design of a close air support aircraft
U.S. military forces are presently searching for the next generation Close Air Support aircraft. The following report presents the SnoDog, a low-cost ($14.8 million) aircraft capable of operating from remote battlefields and unimproved airstrips. The configuration consists of a conventional, low aspect-ratio wing, twin booms, twin canted vertical stabilizers along with a high-mounted joined horizontal tail. A supercritical airfoil for the wing enhances aerodynamic performance, while the SnoDog's instability increases maneuverability over current close air support aircraft. Survivability was incorporated into the design by the use of a titanium tub to protect the cockpit from anti-aircraft artillery, as well as, the twin booms and retracted gear disposition. The booms aid survivability by supplying separated, redundant controls, and the landing gear are slightly exposed when retracted to enable a belly landing in emergencies. Designed to fly at Mach .76, the SnoDog is powered by two low-bypass turbofan engines. Engine accessibility and interchangeable parts make the SnoDog highly maintainable. The SnoDog is adaptable to many different missions, as it is capable of carrying advanced avionics pods, carrying external fuel tanks or refueling in-air, and carrying various types of munitions. This makes the SnoDog a multirole aircraft capable of air-to-air and air-to-ground combat. This combination of features make the SnoDog unique as a close air support aircraft, capable of meeting the U.S. military's future needs
Influence of fluid viscosity and wetting on multiscale viscoelastic lubrication in soft tribological contacts
Friction (and lubrication) between soft contacts is prevalent in many natural and engineered systems and plays a crucial role in determining their functionality. The contribution of viscoelastic hysteresis losses to friction in these systems has been well-established and defined for dry contacts; however, the influence of fluid viscosity and wetting on these components of friction has largely been overlooked. We provide systematic experimental evidence of the influence of lubricant viscosity and wetting on lubrication across multiple regimes within a viscoelastic contact. These effects are investigated for comparatively smooth and rough elastomeric contacts (PTFE-PDMS and PDMS-PDMS) lubricated by a series of Newtonian fluids with systematically controlled viscosity and static wetting properties, using a ball-on-disc tribometer. The distinct tribological behaviour, characterised generally by a decrease in the friction coefficient with increasing fluid viscosity and wettability, is explained in terms of lubricant dewetting and squeeze-out dynamics and their impact on multi-scale viscoelastic dissipation mechanisms at the bulk-, asperity-, sub-asperity- and molecular-scale. It is proposed that lubrication within the (non-molecularly) smooth contact is governed by localised fluid entrapment and molecular-scale (interfacial) viscoelastic effects, while additional rubber hysteresis stimulated by fluid-asperity interactions, combined with rapid fluid drainage at low speeds within the rough contact, alter the general shape of the Stribeck curve. This fluid viscosity effect is in some agreement with theoretical predictions. Conventional methods for analysing and interpreting tribological data, which typically involve scaling sliding velocity with lubricant viscosity, need to be revised for viscoelastic contacts with consideration of these indirect viscosity effects
Asteroid Spin-Rate Study using the Intermediate Palomar Transient Factory
Two dedicated asteroid rotation-period surveys have been carried out using
data taken on January 6-9 and February 20-23 of 2014 by the Intermediate
Palomar Transient Factory (iPTF) in the ~band with -min cadence.
The total survey area covered 174~deg in the ecliptic plane. Reliable
rotation periods for 1,438 asteroids are obtained from a larger data set of
6,551 mostly main-belt asteroids, each with ~detections. Analysis of
1751, PTF based, reliable rotation periods clearly shows the "spin barrier" at
~hours for "rubble-pile" asteroids. We also found a new large-sized
super-fast rotator, 2005 UW163 (Chang et al., 2014), and other five candidates
as well. Our spin-rate distributions of asteroids with ~km shows
number decrease when frequency greater than 5 rev/day, which is consistent to
that of the Asteroid Light Curve Database (LCDB, Warner et al., 2009) and the
result of (Masiero et al., 2009). We found the discrepancy in the spin-rate
distribution between our result and (Pravec et al., 2008, update 2014-04-20) is
mainly from asteroids with mag that might be primarily due to
different survey strategies. For asteroids with ~km, we found a
significant number drop at rev/day. The YORP effect timescale for
small-sized asteroid is shorter that makes more elongate objets spun up to
reach their spin-rate limit and results in break-up. The K-S test suggests a
possible difference in the spin-rate distributions of C- and S-type asteroids.
We also find that C-type asteroids have a smaller spin-rate limit than the
S-type, which agrees with the general sense that the C-type has lower bulk
density than the S-type.Comment: Submitted to ApJ (Jan, 2015). Accepted by ApJ (June, 2015). The whole
set of the folded lightcurves will be available on the published articl
313 new asteroid rotation periods from Palomar Transient Factory observations
A new asteroid rotation period survey have been carried out by using the
Palomar Transient Factory (PTF). Twelve consecutive PTF fields, which covered
an area of 87 deg in the ecliptic plane, were observed in band with a
cadence of 20 min during February 15--18, 2013. We detected 2500 known
asteroids with a diameter range of 0.5 km 200 km. Of these, 313
objects had highly reliable rotation periods and exhibited the "spin barrier"
at hours. In contrast to the flat spin rate distribution of the
asteroids with 3 km 15 km shown by Pravec et al. (2008), our
results deviated somewhat from a Maxwellian distribution and showed a decrease
at the spin rate greater than 5 rev/day. One super-fast-rotator candidate and
two possible binary asteroids were also found in this work.Comment: 18 pages, 20 figures and 2 very long table
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