scholarly journals SOLID PROPELLANTS

2019 ◽  
Vol 92 (1) ◽  
pp. 1-24 ◽  
Author(s):  
B. P. Mason ◽  
C. M. Roland
Keyword(s):  
Research And Development ◽  
Energetic Materials ◽  
State Of The Art ◽  
Solid Propellants ◽  
Black Powder ◽  
The Past ◽  
Insensitive Munitions ◽  
Past Half Century ◽  
Materials Used ◽  
Past Half

ABSTRACT Solid propellants are energetic materials used to launch and propel rockets and missiles. Although their history dates to the use of black powder more than two millennia ago, greater performance demands and the need for “insensitive munitions” that are resistant to accidental ignition have driven much research and development over the past half-century. The focus of this review is the material aspects of propellants, rather than their performance, with an emphasis on the polymers that serve as binders for oxidizer particles and as fuel for composite propellants. The prevalent modern binders are discussed along with a discussion of the limitations of state-of-the-art modeling of composite motors.

Introductory lecture: advances in ion spectroscopy: from astrophysics to biology

2019 ◽  
Vol 217 ◽  
pp. 8-33 ◽  
Author(s):  
Helen J. Zeng ◽  
Nan Yang ◽  
Mark A. Johnson
Keyword(s):  
Present State ◽  
State Of The Art ◽  
Historical Context ◽  
Experimental Methods ◽  
Half Century ◽  
Ion Spectroscopy ◽  
The Past ◽  
Past Half Century ◽  
Introductory Lecture ◽  
Past Half

This introduction provides a historical context for the development of ion spectroscopy over the past half century by following the evolution of experimental methods to the present state-of-the-art.

Public Health Education: Sources, Growth and Operational Philosophy

1980 ◽  
Vol 1 (1) ◽  
pp. 5-18 ◽  
Author(s):  
Dorothy B. Nyswander
Keyword(s):  
Public Health ◽  
Health Education ◽  
Professional Training ◽  
State Of The Art ◽  
Public Health Education ◽  
Health Educators ◽  
Historical Overview ◽  
The Past ◽  
Past Half Century ◽  
Past Half

An historical overview of public health education: its sources, development and operational philosophy. The contributions of many disciplines, particularly social science, and key individuals such as Lewin are traced through the past half century. The emergence of health education as a “helping profession” and the expansion of its focus to broader “marketplaces” of change are highlighted. The state of the art today is reviewed and the functions of health educators described with emphasis on “obtaining people's participation” in programs to bring about change. Problems still existing, particularly professional training, are addressed.

Public Health Education: Sources, Growth and Operational Philosophy

2005 ◽  
Vol 25 (1) ◽  
pp. 5-18
Author(s):  
Dorothy B. Nyswander
Keyword(s):  
Public Health ◽  
Health Education ◽  
Professional Training ◽  
State Of The Art ◽  
Public Health Education ◽  
Health Educators ◽  
Historical Overview ◽  
The Past ◽  
Past Half Century ◽  
Past Half

An historical overview of public health education: its sources, development and operational philosophy. The contributions of many disciplines, particularly social science, and key individuals such as Lewin are traced through the past half century. The emergence of health education as a “helping profession” and the expansion of its focus to broader “marketplaces” of change are highlighted. The state of the art today is reviewed and the functions of health educators described with emphasis on “obtaining people's participation” in programs to bring about change. Problems still existing, particularly professional training, are addressed.

EDITORIAL: Migration and competitiveness: Japan and the United States

2013 ◽  
Vol 10 (2) ◽  
pp. 115-124
Author(s):  
Philip L. Martin
Keyword(s):  
United States ◽  
The United States ◽  
Variable Cost ◽  
Fixed Cost ◽  
Special Issue ◽  
Science And Engineering ◽  
The Past ◽  
Past Half Century ◽  
Key Sectors ◽  
Past Half

Japan and the United States, the world’s largest economies for most of the past half century, have very different immigration policies. Japan is the G7 economy most closed to immigrants, while the United States is the large economy most open to immigrants. Both Japan and the United States are debating how immigrants are and can con-tribute to the competitiveness of their economies in the 21st centuries. The papers in this special issue review the employment of and impacts of immigrants in some of the key sectors of the Japanese and US economies, including agriculture, health care, science and engineering, and construction and manufacturing. For example, in Japanese agriculture migrant trainees are a fixed cost to farmers during the three years they are in Japan, while US farmers who hire mostly unauthorized migrants hire and lay off workers as needed, making labour a variable cost.

Reframing the Sciences of the Long Eighteenth Century

2020 ◽  
Vol 50 (1-2) ◽  
pp. 58-66
Author(s):  
Giuliano Pancaldi
Keyword(s):  
Eighteenth Century ◽  
History Of Science ◽  
Science Policy ◽  
Special Issue ◽  
Half Century ◽  
The Past ◽  
Past Half Century ◽  
History Of ◽  
Long Eighteenth Century ◽  
Past Half

Here I survey a sample of the essays and reviews on the sciences of the long eighteenth century published in this journal since it was founded in 1969. The connecting thread is some historiographic reflections on the role that disciplines—in both the sciences we study and the fields we practice—have played in the development of the history of science over the past half century. I argue that, as far as disciplines are concerned, we now find ourselves a bit closer to a situation described in our studies of the long eighteenth century than we were fifty years ago. This should both favor our understanding of that period and, hopefully, make the historical studies that explore it more relevant to present-day developments and science policy. This essay is part of a special issue entitled “Looking Backward, Looking Forward: HSNS at 50,” edited by Erika Lorraine Milam.

Pakistan’s Development: Successes, Failures, and Future Tasks (Presidential Remarks)

1997 ◽  
Vol 36 (4I) ◽  
pp. 321-331
Author(s):  
Sarfraz Khan Qureshi
Keyword(s):  
Indian Subcontinent ◽  
General Meeting ◽  
The Past ◽  
Past Half Century ◽  
The Social ◽  
The Subject ◽  
Golden Jubilee ◽  
Freedom Movement ◽  
Past Half ◽  
Do So

It is an honour for me as President of the Pakistan Society of Development Economists to welcome you to the 13th Annual General Meeting and Conference of the Society. I consider it a great privilege to do so as this Meeting coincides with the Golden Jubilee celebrations of the state of Pakistan, a state which emerged on the map of the postwar world as a result of the Muslim freedom movement in the Indian Subcontinent. Fifty years to the date, we have been jubilant about it, and both as citizens of Pakistan and professionals in the social sciences we have also been thoughtful about it. We are trying to see what development has meant in Pakistan in the past half century. As there are so many dimensions that the subject has now come to have since its rather simplistic beginnings, we thought the Golden Jubilee of Pakistan to be an appropriate occasion for such stock-taking.

A Scientific Search for Altruism

2018 ◽  
Author(s):  
C. Daniel Batson
Keyword(s):  
Human Nature ◽  
Scientific Method ◽  
Laboratory Experiments ◽  
Fundamental Question ◽  
Empathic Concern ◽  
Altruistic Motivation ◽  
The Past ◽  
Past Half Century ◽  
Series Of Experiments ◽  
Past Half

This book provides an example of how the scientific method can be used to address a fundamental question about human nature. For centuries—indeed for millennia—the egoism–altruism debate has echoed through Western thought. Egoism says that the motivation for everything we do, including all of our seemingly selfless acts of care for others, is to gain one or another self-benefit. Altruism, while not denying the force of self-benefit, says that under certain circumstances we can care for others for their sakes, not our own. Over the past half-century, social psychologists have turned to laboratory experiments to provide a scientific resolution of this human nature debate. The experiments focused on the possibility that empathic concern—other-oriented emotion elicited by and congruent with the perceived welfare of someone in need—produces altruistic motivation to remove that need. With carefully constructed experimental designs, these psychologists have tested the nature of the motivation produced by empathic concern, determining whether it is egoistic or altruistic. This series of experiments has provided an answer to a fundamental question about what makes us tick. Framed as a detective story, the book traces this scientific search for altruism through the numerous twists and turns that led to the conclusion that empathy-induced altruism is indeed part of our nature. It then examines the implications of this conclusion—negative implications as well as positive—both for our understanding of who we are as humans and for how we might create a more humane society.

The Twentysomething Soul

2019 ◽  
Author(s):  
Tim Clydesdale ◽  
Kathleen Garces-Foley
Keyword(s):  
Young Adults ◽  
Religious Commitment ◽  
Religion And Spirituality ◽  
Lost Generation ◽  
Full Spectrum ◽  
Half Century ◽  
The Past ◽  
Past Half Century ◽  
Past Half ◽  
The Way

Few realize how much Americans’ journey through their twenties has changed during the past half-century or understand how incorrect popular assumptions about young adults’ religious, spiritual, and secular lives are. Today’s twentysomethings have been labelled the “lost generation”—for their presumed inability to identify and lead fulfilling lives, “kidults”—for their alleged refusal to “grow up” and accept adult responsibilities, and the “least religious generation”—for their purported disinterest in religion and spirituality. These characterizations are not only unflattering, they are deeply flawed. The Twentysomething Soul tells an optimistic story about American twentysomethings. Drawing on hundreds of interviews and a survey of thousands across America, it introduces readers to the full spectrum of American young adults, many of whom live purposefully, responsibly, and reflectively. Some prioritize faith and spirituality. Others reject their childhood religion to explore alternatives and practice a personal spirituality. Still others sideline religion and spirituality until their lives get settled or reject organized religion completely. There is change occurring in the religious and spiritual lives of young adults, but little of it is among the 1 in 4 American twentysomethings who have consistently prioritized religious commitment during the past half-century. The change is rather among the now 3 in 10 young adults who, though intentionally unaffiliated with religion, affirm a variety of religious, spiritual, and secular beliefs. The Twentysomething Soul will change the way readers view contemporary young adults, giving an accurate—and refreshing—understanding of their religious, spiritual, and secular lives.

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