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The Origin of Records and Archives in the United States and the Formation of Archival System: Focusing on the Period from the Early 17th Century to the Mid 20th (미국의 기록(records) 및 아카이브즈(archives)의 역사적 기원과 관리·보존의 역사 17세기 초부터 20세기 중반까지를 중심으로)

  • Lee, Seon Ok
    • The Korean Journal of Archival Studies
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    • no.80
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    • pp.43-88
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    • 2024
  • The National Archives and Records Administration (NARA) is a relatively quiet latecomer to the traditional archives of the Western world. Although the United States lacks a long history of organized public records·archives management, it has developed a modern system optimized for the American historical context. This system focuses on the systematic management and preservation of the vast amount of modern records produced and collected during the tumultuous 20th century. As a result, NARA has established a modern archival system that is optimized for the American historical context. The U.S. public records·archives management system is based on the principle that records·archives are the property of the American people and belong to the public. This concept originated during the British colonial era when records were used to safeguard the rights of the colonies as self-governing citizens. For Americans, records and archives have long been a symbol of the nation's identity, serving as a means of protecting individual freedoms, rights, and democracy throughout the country's history. It is natural, therefore, that American life and history should be documented, and that the recorded past should be managed and preserved for the nation's present and future. The public records·archives management system in the United States is the result of a convergence of theories, practices, lessons learned, and ideas that have been shaped by the country's history, philosophies, and values about records, and its unique experience with records management. This paper traces the origins of records and archives in the United States in a historical context to understand the organic relationship between American life and records. It examines the process of forming a modern public records management system that is both uniquely American and universal to the American context without falling into the two forms of traditions that reflect the uniqueness of American history.

Dynamical Study on the Blasting with One-Free-Face to Utilize AN-FO Explosives (초유폭약류(硝油爆藥類)를 활용(活用)한 단일자유면발파(單一自由面發破)의 역학적(力學的) 연구(硏究))

  • Huh, Ginn
    • Economic and Environmental Geology
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    • v.5 no.4
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    • pp.187-209
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    • 1972
  • Drilling position is one of the most important factors affecting on the blasting effects. There has been many reports on several blasting factors of burn-cut by Messrs. Brown and Cook, but in this study the author tried to compare drilling positions of burn-cut to pyramid-cut, and also to correlate burn-cut effects of drilling patterns, not being dealt by Prof. Ito in his theory, which emphasized on dynamical stress analysis between explosion and free face. According to former theories, there break out additional tensile stress reflected at the free face supplemented to primary compressive stress on the blasting with one-free-face. But with these experimented new drilling patterns of burn-cut, more free faces and nearer distance of each drilling holes make blasting effects greater than any other methods. To promote the above explosive effect rationary, it has to be considered two important categories under-mentioned. First, unloaded hole in the key holes should be drilled in wider diameter possibly so that it breaks out greater stress relief. Second, key holes possibly should have closer distances each other to result clean blasting. These two important factors derived from experiments with, theories of that the larger the dia of the unloaded hole, it can be allowed wider secondary free faces and closes distances of each holes make more developed stress relief, between loaded and unloaded holes. It was suggested that most ideal distance between holes is about 4 clearance in U. S. A., but the author, according to the experiments, it results that the less distance allow, the more effective blasting with increased broken rock volume and longer drifted length can be accomplished. Developed large hole burn-cut method aimed to increase drifting length technically under the above considerations, and progressive success resulted to achieve maximum 7 blasting cycles per day with 3.1m drifting length per cycle. This achievement originated high-speed-drifting works, and it was also proven that application of Metallic AN-FO on large hole burn-cut method overcomes resistance of one-free-face. AN-FO which was favored with low price and safety handling is the mixture of the fertilizer or industrial Ammonium-Nitrate and fuel oil, and it is also experienced that it shows insensible property before the initiation, but once it is initiated by the booster, it has equal explosive power of Ammonium Nitrate Explosives (ANE). There was many reports about AN-FO. On AN-FO mixing ratio, according to these experiments, prowdered AN-FO, 93.5 : 6.5 and prilled AN-FO 94 : 6, are the best ratios. Detonation, shock, and friction sensities are all more insensitive than any other explosives. Residual gas is not toxic, too. On initation and propagation of the detonation test, prilled AN-FO is more effective than powered AN-FO. AN-FO has the best explosion power at 7 days elapsed after it has mixed. While AN-FO was used at open pit in past years prior to other conditions, the author developed new improved explosives, Metallic AN-FO and Underwater explosive, based on the experiments of these fundmental characteristics by study on its usage utilizing AN-FO. Metallic AN-FO is the mixture of AN-FO and Al, Fe-Si powder, and Underwater explosive is made from usual explosive and AN-FO. The explanations about them are described in the other paper. In this study, it is confirmed that the blasting effects of utilizing AN-FO explosives are very good.

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