Computer program for interplanetary conic patching

Computer program enables study of one-way transfers, single and double planet flybys, single and double planet stopovers, or mixed flyby and stopover trajectories. In each operation it first computes the heliocentric conic which connects the centers of the launch and target planets and requires a given trip time

Could early warning systems have helped to predict the sub prime crisis?

One of the features of the sub-prime crisis, that began in August 2007, was its unexpected nature. It came as a surprise not only to most financial market participants but also in some degree to the policy community. In this context, we seek to assess whether early warning systems based on the logit and binomial tree approaches on the UK and US economies could have helped to warn about the crisis. We also consider a “check list approach” of indicators based on history. Although not all of the complementary approaches are successful, we contend that our work suggests that a broadening of approaches of macroprudential analysis is appropriate

Veterans’ Benefits: Pension Benefit Programs

[Excerpt] The Department of Veterans Affairs (VA) administers pension programs for certain low-income veterans and their surviving spouses and dependent children. This report discusses the Improved Disability Pension, which makes payments to certain low-income veterans, and the Improved Death Pension, which makes payments to certain low-income surviving spouses and dependent children of deceased veterans. To qualify for either program, individuals must have become eligible for payments on or after January 1, 1979. Both pension programs were created by P.L. 95-588, the Veterans and Survivors Pension Improvement Act of 1978. In addition, this report discusses a special pension program for Medal of Honor recipients. This report does not discuss several other pension programs that are administered by the VA, such as the Old Law Disability Pension and the Section 306 Disability Pension, which make payments to low-income veterans, and the Old Law Death Pension and the Section 306 Death Pension, which make payments to low-income surviving spouses and dependent children of veterans; these programs apply only to veterans and their survivors who became entitled to such benefits before 1979. This report also does not discuss pension programs for veterans of specific periods of war before World War I, such as the Civil War, the Indian Wars, and the Spanish-American War. Finally, this report does not address the military retirement system. For information on that system, see CRS Report RL34751, Military Retirement: Background and Recent Developments, by Kristy N. Kamarck

Pure Numbers Effects, Market Power, and Tacit Collusion in Posted Offer Markets

This paper studies the effects of seller concentration and static market power on tacit collusion in extensively repeated laboratory posted-offer markets. Contrary to the implications of some earlier research, we find that tacit collusion does not become pervasive with extensive repetition. In a ‘strong no power’ design persistently competitive outcomes are observed in markets with three or four sellers. Even duopolies are frequently competitive in this design. Unilateral market power raises prices, as predicted. However, static Nash predictions fail to organize outcomes across power treatments, because tacit collusion moves inversely with concentration. Excess capacity appears to explain observed tacit collusion levels.experiments, market concentration, market power

Fatigue failure load indicator

An indicator for recording the load at which a fatigue specimen breaks during the last cycle of a fatigue test is described. A load cell is attached to the specimen which is alternately subjected to tension and compression loads. The output of the load cell which is proportional to the load on the specimen is applied to the input of a peak detector. Each time the specimen is subjected to a compression load, means are provided for applying a positive voltage to the rest of the peak detector to reset it. During the last cycle of the tension load the peak detector measures the maximum load on the specimen. Means are provided for disconnecting the load cell from the peak detector when there is a failure in the specimen