OCB Mode

This paper was prepared for NIST, which is considering new block-cipher modes of operation. It describes a parallelizable mode of operation that simultaneously provides both privacy and authenticity. OCB mode encrypts-and-authenticates an arbitrary message M\in\bits^* using only $\lceil |M|/n\rceil + 2$ block-cipher invocations, where $n$ is the block length of the underlying block cipher. Additional overhead is small. OCB refines a scheme, IAPM, suggested by Jutla [IACR-2000/39], who was the first to devise an authenticated-encryption mode with minimal overhead compared to standard modes. Desirable new properties of OCB include: very cheap offset calculations; operating on an arbitrary message M\in\bits^*; producing ciphertexts of minimal length; using a single underlying cryptographic key; making a nearly optimal number of block-cipher calls; avoiding the need for a random IV; and rendering it infeasible for an adversary to find pretag collisions . The paper provides a full proof of security for OCB

Estimating the location of the open-closed magnetic field line boundary from auroral images

The open-closed magnetic field line boundary (OCB) delimits the region of open magnetic flux forming the polar cap in the Earth’s ionosphere. We present a reliable, automated method for determining the location of the poleward auroral luminosity boundary (PALB) from far ultraviolet (FUV) images of the aurora, which we use as a proxy for the OCB. This technique models latitudinal profiles of auroral luminosity as both a single and double Gaussian function with a quadratic background to produce estimates of the PALB without prior knowledge of the level of auroral activity or of the presence of bifurcation in the auroral oval. We have applied this technique to FUV images recorded by the IMAGE satellite from May 2000 until August 2002 to produce a database of over a million PALB location estimates, which is freely available to download. From this database, we assess and illustrate the accuracy and reliability of this technique during varying geomagnetic conditions. We find that up to 35% of our PALB estimates are made from double Gaussian fits to latitudinal intensity profiles, in preference to single Gaussian fits, in nightside magnetic local time (MLT) sectors. The accuracy of our PALBs as a proxy for the location of the OCB is evaluated by comparison with particle precipitation boundary (PPB) proxies from the DMSP satellites. We demonstrate the value of this technique in estimating the total rate of magnetic reconnection from the time variation of the polar cap area calculated from our OCB estimates

MARKET AREA SENSITIVITY AS A MEASURE OF RAILROAD-BARGE COMPETITION IN THE OKLAHOMA-KANSAS WHEAT TRANSPORTATION MARKET

Crop Production/Industries, Public Economics,

Gray’s revised Reinforcement Sensitivity Theory in relation to Attention-Deficit/Hyperactivity and Tourette-like behaviors in the general population

Attention-Deficit/Hyperactivity Disorder (ADHD) and Tourette Syndrome (TS) present as distinct conditions clinically; however, they show comorbidity and inhibitory control deficits have been proposed to underlie both. The role of reinforcement sensitivity in ADHD has been studied previously, but no study has addressed this in relation to TS-like behaviors in the general population. The present study examined these associations within the remit of the revised Reinforcement Sensitivity Theory (rRST). One hundred and thirty-eight participants completed psychometric measures of the rRST, and self-report checklists for ADHD- and TS-like behaviors

Willing and able: action-state orientation and the relation between procedural justice and employee cooperation

Existing justice theory explains why fair procedures motivate employees to adopt cooperative goals, but it fails to explain how employees strive towards these goals. We study self-regulatory abilities that underlie goal striving; abilities that should thus affect employees’ display of cooperative behavior in response to procedural justice. Building on action control theory, we argue that employees who display effective self-regulatory strategies (action oriented employees) display relatively strong cooperative behavioral responses to fair procedures. A multisource field study and a laboratory experiment support this prediction. A subsequent experiment addresses the process underlying this effect by explicitly showing that action orientation facilitates attainment of the cooperative goals that people adopt in response to fair procedures, thus facilitating the display of actual cooperative behavior. This goal striving approach better integrates research on the relationship between procedural justice and employee cooperation in the self-regulation and the work motivation literature. It also offers organizations a new perspective on making procedural justice effective in stimulating employee cooperation by suggesting factors that help employees reach their adopted goals