Modeling short-range ballistic missile defense and Israel's Iron Dome system

This paper develops a model of short-range ballistic missile defense and uses it to study the performance of Israel’s Iron Dome system. The deterministic base model allows for inaccurate missiles, unsuccessful interceptions, and civil defense. Model enhancements consider the trade-offs in attacking the interception system, the difficulties faced by militants in assembling large salvos, and the effects of imperfect missile classification by the defender. A stochastic model is also developed. Analysis shows that system performance can be highly sensitive to the missile salvo size, and that systems with higher interception rates are more “fragile” when overloaded. The model is calibrated using publically available data about Iron Dome’s use during Operation Pillar of Defense in November 2012. If the systems performed as claimed, they saved Israel an estimated 1778 casualties and $80 million in property damage, and thereby made preemptive strikes on Gaza about 8 times less valuable to Israel. Gaza militants could have inflicted far more damage by grouping their rockets into large salvos, but this may have been difficult given Israel’s suppression efforts. Counter-battery fire by the militants is unlikely to be worthwhile unless they can obtain much more accurate missiles.

The efficacy of anti-predator behaviour in the wood fog tadpole (Rana sylvatica) /

Activity has been suggested as an important behaviour that is tightly linked with predator avoidance in tadpoles. In this thesis I examine predator-prey relationships using wood frog tadpoles {Rana sylvaticd) as prey and dragonfly larvae {AnaxJunius) and backswimmers {Notonecta undulatd) as predators. I explore the role of prey activity in predator attack rates, prey response to single and multiple predator introductions, and prey survivorship. The data suggest that Anax is the more successful predator, able to capture both active and inactive tadpoles. In contrast, Notonecta strike at inactive prey less frequently and are seldom successftil when they do. A mesocosm study revealed that the presence of any predator resulted in reduced activity level of tadpoles. Each predator species alone had similar effects on tadpole activity, as did the combined predator treatment. Tadpole survivorship, however, differed significantly among both predator treatments and prey populations. Tadpwles in the combined predator treatment had enhanced risk; survivorship was lower than that expected if the two predators had additive effects. Differences in survivorship among wood frog populations showed that tadpoles from a lake habitat had the lowest survivorship, those from a shallow pond habitat had an intermediate survivorship, and tadpoles from a marsh habitat had the highest survivorship. The frequency of interactions with predators in the native habitat may be driving the population differences observed. In conclusion, results from this study show that complex interactions exist between predators, prey, and the environment, with activity playing a key role in the survival of tadpoles.

Characterizing the impact of multiple potential enemies (predators and parasites) on the behaviour of ranid tadpoles

In order to fully understand an organism's behaviours the interactions between multiple enemies or selective pressures need to be considered, as these interactions are usually far more complex than the simple addition of their effects in isolation. In this thesis, I consider the impact of multiple enemies (fish predators and parasites) on the behaviour of three larval anurans (Lithobates sylvaticus, L. clamitans and L. catesbeianus). I also determine whether species that differ in life-histories and habitat preferences possess different antipredator mechanisms and how this affects species responses to multiple enemies. I show that the three Ranid larvae respond differently to the trade-off imposed by the presence of both fish predators and trematode parasites within the environment. The two more permanent pond breeders (L. clamitans and L. catesbeianus) increased activity when in the combined presence of predators and parasites. In contrast, the temporary pond breeder (L. sylvaticus) decreased activity in the combined presence of predator and parasites, in the same manner as they responded to fish alone. Further, the presence of fish along with parasites increased the susceptibility of both L. sylvaticus and L. clamitans to trematode infection, whereas parasite infection in L. catesbeianus was unaffected by the presence of fish. A second experiment to assess palatability of the three anuran species to fish, revealed a range of palatabilities, with L. catesbeianus being least palatable, L. clamitans being somewhat unpalatable, and L. sylvaticus being highly palatable. This result helps to explain the species differences in tthe observed behaviour to the combined presence of fish and parasites. In conclusion, the results from this study highlight the importance of considering multiple selective pressures faced by organisms and how this shapes their behaviour.

National Intelligencer Vol. XVI, No. 2193- October 15, 1814

The Intelligencer was an American newspaper that was established, in 1800, in Washington by Samuel Harrison Smith, a young Jeffersonian- Republican from Philadelphia. War of 1812 related content includes: Page 1: Major General Winfield Scott's arrival in Washington escorted by Colonel Laval's cavalry; report from Sackett's Harbour on the American and British navies; a debate on a bill to temporarily remove the seat of government from the City of Washington due to the war; the Military Committee wishing to have the President commission gold medals for distinguished service for Major Generals Brown and Scott and silver medals to Brigadier Generals Ripley, Miller and Porter for their efforts at Chippewa, Erie and Niagara as well as gold medals to Brigadier General Gaines for efforts at Erie and Brigadier General Macomb for efforts at Plattsburg; resolutions of the House on the victory of Commodore Thomas Macdonough at the Battle on Lake Champlain; Page 2: more detail on the proposed removal of the seat of government from Washington; Page 3: a letter from Major General Andrew Jackson to the Secretary of War on repelling the British at Fort Bowyer on the Point of Mobile and naval battle reports on the vessels Hermes, Sophie, and Carron; a letter from Major William Lawrence to Andrew Jackson on the battle at Fort Bowyer; military promotions of Alexander Macomb, Roger Jones, J. Hindman; more on the removal of the seat of government; citizens of Washington offering to volunteer in defense of the city; banks willing to loan the government funds to re-build destroyed government buildings; assignments of Major General Scott, General Winder and Major General Gaines; report of 300 British prisoners from Fort Erie passed through Washington; Montreal newspaper report condemning Provost for his actions at the Battle of Lake Champlain; trouble with stage coaches traveling between New Haven and Bridgeport due to cannon fire; report of a British naval squadron appearing off New Port and by Long Island and New Bedford; report of enemy naval movements from Norfolk; announcement of a book entitled "A Narrative of the Battle of Bladensburg" by and officer of General Smith; Page 4: report on the amassing navy at Kingston under Drummond and the defenses at Sackett's Harbor; report of American and British naval news from Nova Scotia and the east coast; actions of the American sloop of war, The Peacock, in international waters; an enlistment announcement by Captain Perrin Willis of the 2nd Regiment Infantry; listing of American officers and privates released from parole on October 13; Other notices report on stray horses, properties for sale, runaway slaves, imprisonments, missing livestock, medical lectures at the University of Maryland, stage lines, auctions, etc. The paper was a supporter of the Jefferson and Madison administrations until 1810 when it was sold to Joseph Gales Jr. from North Carolina. In 1812 William Seaton joined Gales as a publishing partner. This paper made significant contributions to the nation and wielded considerable influence in political circles during its publication. It has been praised for its "high standard of journalistic excellence and high intellectual level of its contents". (William E. Ames , National Intelligencer: Washington's Leading Political Newspaper) The Intelligencer was, until 1810, named the National Intelligencer, and Washington Advertiser. It was a tri-weekly paper and had a peak circulation of 6, 000. Publication was suspended in 1869.

Public Notices - Niagara Region collection

This is a collection of public notices posted by various villages, towns and townships in the Niagara Region. The notices alert residents to various civic events and initiatives.

The salvo combat model with area fire

This paper analyzes versions of the salvo model of missile combat where area fire is used by one or both sides in a battle. While these models share some properties with the area fire Lanchester model and the aimed fire salvo model, they also display some interesting differences, especially over the course of several salvos. Whereas the relative size of each force is important with aimed fire, with area fire it is the absolute size that matters. Similarly, while aimed fire exhibits square law behavior, area fire shows approximately linear behavior. When one side uses area and the other uses aimed fire, the model displays a mix of square and linear law behavior.