Performance evaluation of ductless personalized ventilation in comparison with desk fans using numerical simulations

The performance of ductless personalized ventilation (DPV) was compared to the performance of a typical desk fan since they are both stand-alone systems that allow the users to personalize their indoor environment. The two systems were evaluated using a validated computational fluid dynamics (CFD) model of an office room occupied by two users. To investigate the impact of DPV and the fan on the inhaled air quality, two types of contamination sources were modelled in the domain: an active source and a passive source. Additionally, the influence of the compared systems on thermal comfort was assessed using the coupling of CFD with the comfort model developed by the University of California, Berkeley (UCB model). Results indicated that DPV performed generally better than the desk fan. It provided better thermal comfort and showed a superior performance in removing the exhaled contaminants. However, the desk fan performed better in removing the contaminants emitted from a passive source near the floor level. This indicates that the performance of DPV and desk fans depends highly on the location of the contamination source. Moreover, the simulations showed that both systems increased the spread of exhaled contamination when used by the source occupant

The Church of Sweden on the Delaware, 1638-1831

A discussion of the Swedish Lutheran Church in New Sweden covering the churches of Holy Trinity at Christina, now Wilmington, Delaware; an early Tinicum Island church and Wicaco church from which grew the Gloria Dei Church in Philadelphia; St. James Church in Kingsessing, now in Philadelphia; Christ or Old Swedes in Upper Merion, now in Philadelphia; Raccoon, now Swedesboro, and Penns Neck, now Churchtown or Lower Penns Neck, New Jersey. The churches which survived to 1776 became Anglican.https://digitalcommons.augustana.edu/ahsbooks/1002/thumbnail.jp

A History of the Augustana Library, 1860-1990: an international treasure

Table of Contents: A Royal Beginning--From Chicago to Paxton--The Tower in Rock Island--In Old Main--C. O. Granere--The Denkmann Gift--Marcus Skarstedt--Ira O. Nothstein--William Baehr--Donald Rod--Lucien White--Ernest Espelie--John Caldwell--A Living Library--Librarians: Terms of Service. Appendices: Library Publications--Publications of the Augustana Historical Society--Occasional Papers--The Institute: Historical Swedish Handbooks--Sources.https://digitalcommons.augustana.edu/ahsbooks/1004/thumbnail.jp

Avoiding Vietnam: The U.S. Army\u27s Response to Defeat in Southeast Asia

As American operations against terrorism spread around the globe to places like Afghanistan and the Philippines, an increasing tendency has been for commentators to draw parallels with past experience in Vietnam. Even soldiers on the ground have begun to speak in such terms. The author analyzes the Army\u27s response to that defeat in Southeast Asia and its long-term impact. Contrary to the accepted wisdom that nations which lose wars tend to learn best how to correct their mistakes, he argues that Americans tried to forget the unhappy experience with counterinsurgency by refocusing on conventional wars. While that process eventually produced the powerful force that won the Persian Gulf War, it left an Army with force structure, doctrine, and attitudes that are much less applicable to the peace operations and counterterrorism campaign it now faces. The author asserts that the Army must change in order to operate effectively in the full spectrum of future requirements, and it is time to reexamine the war in Vietnam. He also draws attention to the service\u27s Lessons Learned process, and provides insights as to how the experience gained in Operation ENDURING FREEDOM should be analyzed and applied.https://press.armywarcollege.edu/monographs/1813/thumbnail.jp

Facing the Hydra: Maintaining Strategic Balance while Pursuing a Global War against Terrorism

The author analyzes the impact of the war on terrorism and the requirements of the 2001 Quadrennial Defense Review on the many essential missions conducted by the U.S. Armed Forces. Focusing primarily on the Army, he highlights the requirements associated with combat operations against terrorists, accelerating transformation and the new emphasis on homeland security and force protection. At the same time, he points out that the Army and the other Services must remain involved worldwide in day-to-day assurance, dissuasion, and deterrence activities; execution of peace operations and other smaller-scale contingencies; and remaining ready for other major combat operations. The author asserts that these obligations require the Army to reshape and expand its force structure. Failure to do so places critical missions at risk around the world could lead to replacement of operational victory in the war on terrorism with strategic failure, as regional instability increases around the world.https://press.armywarcollege.edu/monographs/1819/thumbnail.jp

Landpower and Crises: Army Roles and Missions in Smaller-Scale Contingencies During the 1990s

The author analyzes the role of landpower in the 170 smaller-scale contingencies conducted by the United States during the last decade. He divides such contingencies into engagement, enhanced deterrence, hostility, and stabilization phases, and discusses the military\u27s role in each one. The author especially emphasizes the recurring problems in the planning, execution, and force structure for stabilization tasks, including nation-building. He concludes that, despite the desire of American leaders to limit military involvement in such missions, it is unavoidable because of the capability mismatch between military and civilian organizations, combined with the requirements of peace operations and the character of American soldiers. Recommendations include acceptance of some degree of nation-building as the Army\u27s mission and adapting its force structure, training, and planning accordingly.https://press.armywarcollege.edu/monographs/1840/thumbnail.jp

Creating Great Expectations: Strategic Communications and American Airpower

Americans have always been uniquely attracted to airpower, a fact that has been successfully exploited by generations of U.S. Air Force leaders in information campaigns. But as a result, the nation has often entered conflicts with exorbitant expectations about what airpower could actually accomplish, creating unique challenges in strategic communications when promises did not match reality, especially in recent conflicts. Adaptive enemies have also become very adept at using their own carefully crafted information campaigns to counter what is America’s greatest asymmetric advantage on the battlefield.https://press.armywarcollege.edu/monographs/1387/thumbnail.jp

Precedents, Variables, and Options in Planning a U.S. Military Disengagement Strategy from Iraq

The questions of how to empower the Iraqis most effectively and then progressively withdraw non-Iraqi forces from that country is one of the most important policy problems currently facing the United States. The authors seek to present the U.S. situation in Iraq in all of its complexity and ambiguity, with policy recommendations for how that withdrawal strategy might be most effectively implemented. They consider previous instances of U.S. military occupation of foreign countries and the difficulty of maintaining domestic support for such operations. The authors view the empowerment of a viable Iraqi central government and a security force to defend its authority as vital to the future of that country, but also suggest that there are severe constraints on the potential for the United States to sustain its military presence in that country at the current level. They conclude that the United States must be prepared to withdraw from Iraq under non-optimal conditions and that the chief U.S. goals should be to devise an exit strategy for Iraq that focuses on bolstering Iraqi government legitimacy even if this does not involve creating a Western style democracy. The authors strongly reject the idea withdrawing from Iraq by the use of a formal timetable, and call for the U.S. to continue its policy of renouncing permanent Iraqi bases.https://press.armywarcollege.edu/monographs/1731/thumbnail.jp

Reconstructing Iraq: Insights, Challenges, and Missions for Military Forces in a Post-Conflict Scenario

In October 2002, the U.S. Army War College\u27s Strategic Studies Institute, in coordination with the Office of the Army Deputy Chief of Staff/G-3, initiated a study to analyze how American and coalition forces can best address the requirements that will necessarily follow operational victory in a war with Iraq. The objectives of the project were to determine and analyze probable missions for military forces in a post-Saddam Iraq; examine associated challenges; and formulate strategic recommendations for transferring responsibilities to coalition partners or civilian organizations, mitigating local animosity, and facilitating overall mission accomplishment in the war against terrorism. The study has much to offer planners and executors of operations to occupy and reconstruct Iraq, but also has many insights that will apply to achieving strategic objectives in any conflict after hostilities are concluded. The current war against terrorism has highlighted the danger posed by failed and struggling states. If this nation and its coalition partners decide to undertake the mission to remove Saddam Hussein, they will also have to be prepared to dedicate considerable time, manpower, and money to the effort to reconstruct Iraq after the fighting is over. Otherwise, the success of military operations will be ephemeral, and the problems they were designed to eliminate could return or be replaced by new and more virulent difficulties.https://press.armywarcollege.edu/monographs/1806/thumbnail.jp