Hans Christian Jacobsen

Andre Begivenheder og Egenskaber:

• Beskæftigelse: King, Washington, USA; Konsul; Adresse:
  Seattle
• Beskæftigelse: 1896, Nyborg, Vindinge, Svendborg; Møller
• Udvandring: 1917

Notater:

I kirken 15 May 1870

Beskæftigelse:
DBL 3. udg.: Vicekonsul i Seattle. KB ved ægtefælle Thomine Asmussens død: Konsul, Seattle.

Beskæftigelse:
Ved vielsen: Mølleejer i Nyborg.
Datteren Ingrid f. Slotsmøllen, Torvet, Nyborg.

Begravet:
Gravsten afbildet (2008). Sammen med ægtefællerne Ellen M.E. Siegumfeldt, og Thomine Asmussen.

Hans blev gift med Ellen Marie Elisabeth la Cour Siegumfeldt den 6 sep. 1896 i Søften, Vester Lisbjerg, Århus. Ellen blev født den 6 sep. 1869; døde den 7 jan. 1953 i King, Washington, USA; blev begravet i 1953 i Santa Barbara, Californien, USA. [Gruppeskema] [Familietavle]

Hans blev gift med Thomine Asmussen den Ja, dato ukendt. Thomine blev født den 29 nov. 1881 i Nørre Nebel, Vester Horne, Ribe; blev døbt den 24 feb. 1882 i Nørre Nebel, Vester Horne, Ribe; døde den 7 jul. 1964 i Sankt Peder, Slagelse, Sorø; blev begravet i 1964 i Santa Barbara, Californien, USA. [Gruppeskema] [Familietavle]

Andre Begivenheder og Egenskaber:

• Udvandring: 1917
• Beskæftigelse: 1921; Ingeniør
• Beskæftigelse: 1936, Santa Clara, Californien, USA; Professor; Adresse:
  Stanford University
• Bopæl: 1940, Santa Clara, Californien, USA; Adresse:
  Cabrillo Avenue, Palo Alto
• Beskæftigelse: 1946; Kommandør

Notater:

Gift 2: 19 Feb 1965,Los Angeles, med Mary Louise Heffernan (f.5 Sep 1921, Wilkes-Barre, Pennsylvania).

Nekrolog:
LYDIK SIEGUMFELDT JACOBSEN 1897-1976
BY JOHN A. BLUME​
Lydik Siegumfeldt Jacobsen, Stanford University Professor Emeritus, Member of the National Academy of Engineering, Past President and Honorary Member of the Seismological Society of America, and first President of the Earthquake Engineering Research Institute, died on December 22, 1976, following a stroke.
Dr. Jacobsen was internationally known for his pioneering work in determining the dynamic characteristics of buildings and other structures and their response to earthquake ground motion and other disturbances, as well as for his research and teaching in vibrations and dynamics. He directed the Vibration Laboratory at Stanford University from 1926 until his retirement, in 1962, and was Head of the Mechanical Engineering Department from 1949 to 1961. He coauthored, with Robert S. Ayre, a standard text, Engineering Vibrations (McGraw Hill, 1958), and he wrote many technical papers.
Lydik Jacobsen was born June 17, 1897, in Nyborg, Denmark, where his father owned a steam-powered flour mill. After completing the Danish equivalent of an American high school education, Lydik worked in various flour mills and at a fish hatchery, where he enjoyed manual labor. In 1917, his father, Hans Christian Jacobsen, sold his mill and took his wife and five children, including Lydik, to California. Lydik began work in the Sperry Flour Mill in Stockton, California, where he soon supervised all machinery on one floor. Because of his growing interest in the mechanical aspects of milling, he was encouraged to attend Stanford, where he obtained his Bachelor of Arts degree in mechanical engineering after three years of accelerated study. In 1921 he became a junior engineer with Westinghouse Electric Corporation in Pittsburgh, Pennsylvania, where he worked with S. Timoshenko. In 1924 Professor Durand, another engineer who later became famous, persuaded Lydik to return to Stanford for graduate study and provided him with an instructorship as a source of financial aid.
In 1927 Lydik obtained his Doctor of Philosophy degree in physics at Stanford and also became a U.S. citizen. That same year, with some financial aid obtained by Dr. Bailey Willis, he started a vibration laboratory at Stanford with a large shaking table. The combination of the 1925 Santa Barbara earthquake, Dr. Willis' aid and encouragement, and the opportunity to apply his knowledge of vibration from physics and mechanical engineering all contributed toward developing Dr. Jacobsen's interest in the problem of how buildings respond to earthquake-induced ground motion.
In 1931 Dr. Jacobsen was awarded a Guggenheim fellowship in applied mechanics that enabled him to visit universities and laboratories in five European countries. He became a Full Professor in Mechanical Engineering at Stanford in 1936. He was a Visiting Professor at the University of Michigan in 1938 and at the Illinois Institute of Technology in 1941. During a leave from Stanford in 1953 and 1954, he was a Fulbright Professor at Den Polytekniske Laeranstalt (the Danish Polytechnic Institute) in Copenhagen. After he retired from teaching, in 1962, he cofounded Agbabian-Jacobsen Associates, a consulting engineering firm, in which he was active until he retired in 1969. He continued his individual consulting practice until his death.
During World War II, he analyzed 271 U.S. Navy ships of all types and served aboard 130 of them to study ways to reduce sounds and vibrations and thus decrease detection by enemy submarines. He left the service in 1946 as a Commander in the Naval Reserve and with a U.S. Navy Commendation Medal.
Dr. Jacobsen published about forty scholarly, thorough, and precisely written papers involving a great deal of thought and effort on new subject matter in whose development he, personally, had played either a sole or a major role, including mechanics, stress analysis, vibrations, models, dynamic behavior of models, damping, shock, blast effects, ship vibrations, hydrodynamics, shaking table research, mathematics, and earthquake motion. In addition to his published works, he wrote many reports, both public and private, for clients during his decades of consulting work for industry and Government; such unpublished reports by a consultant of Dr. Jacobsen's caliber often involved more complexity, discovery, and innovation than was generally found in his published works.
Dr. Jacobsen received many honors and awards, but no doubt fewer than he deserved because of his frank honesty in all matters and also because his audience's understanding rarely matched his own. He was a pioneer in earthquake dynamics, but he was also a mechanical engineer, a mathematician, and a physicist who attempted to explain new and complex building dynamics to structural engineers, architects, and public officials. The work was made more difficult with warning public interest in such matters shortly after each damaging earthquake.
He was elected to the National Academy of Engineering in 1975; his citation was for ''outstanding research, teaching, practice, and writing in mechanical and structural vibrations and shock." He served as President of the Seismological Society of America from 1953 to 1955 and was elected an Honorary Member in 1974. He was Chairman of the U.S. Coast and Geodetic Survey's Advisory Committee on Engineering Seismology from 1947 to 1949. He was one of the founders and the first President of the Earthquake Engineering Research Institute in 1949 and was elected an Honorary Member in 1969. He was a Fellow of the American Society of Engineering Education. His accomplishments are listed in Who's Who in America, Who's Who in Engineering, American Men of Science, Blue Book of Denmark, and Danes in the World.
Lydik Jacobsen was a dynamic person in every sense of the word- intelligent, vigorous, enthusiastic, energetic, friendly, fluent, greatly interested in people as well as in science and engineering, and a dedicated worker with much endurance. He enjoyed his work, especially research or a challenging, difficult problem. He was proud of the fact that, in 1975, eight of his former students were members of the National Academy of Engineering.
Lydik Jacobsen was respected by all his peers, even those who might not always agree with him. Some of Dr. Jacobsen's work-for example, his development of the phase-plane-delta method of treating inelastic, nonharmonic, vibrating systems-would have been much more widely applied had it not been for the computer, which later made such procedures unnecessary. The same is true of his dynamic (mechanical) models of buildings tested on the shaking table, which were replaced by electric analogs or by high-speed digital computers. Nevertheless, the pioneering innovation was there, and it helped to provide a solid base for later development with more exotic equipment. Lydik Jacobsen's pioneering work in vibrations and in approaching the earthquake problem as one of dynamics rather than statics was a great milestone that shall always be on record, remembered by all who knew him, and appreciated in the future by those who did not know him.
Dr. Jacobsen's survivors, besides his widow Mary Louise of Laguna Hills, California, include his first wife, Doris (Wetzel), of Menlo Park; two sons, Erland, of Fresno, and Ian, of Honolulu; and a daughter, Ellen Yazar, of Ankara, Turkey. His brother, Theodor, a retired professor of astronomy, lives in Seattle; a sister, Ingrid Wilson lives in Los Angeles; and two sisters, Kirsten Gregersen and Lisse Lindman, live in Santa Barbara.

Bopæl:
US Census 1940, 668 Cabrillo Avenue, Palo Alto, Santa Clara:
Jacobsen, Lydik, head, 42, Denmark, Professor, Mechanical Engineering, University
Jacobsen, Dorris, Wife, 32, Minnesota
Jacobsen, Erland, Son 5, California
Jacobsen, Jan 1, Son, California
samt en tjenestepige.


Beskæftigelse:
US Navy, af reserven.

Begravet:
Buried at sea. Mindeplade i Solvang (afbildet).

Lydik blev gift med Doris Isabelle Wetzel den 29 jun. 1928 i Los Angeles, Californien, USA. Doris blev født den 28 maj 1907 i Hennepin, Minnesota, USA; døde den 2 apr. 2001; blev begravet i 2001 i Santa Barbara, Californien, USA. [Gruppeskema] [Familietavle]

Andre Begivenheder og Egenskaber:

• Udvandring: 20 jun. 1917
• Bopæl: 1921, Napa, Californien, USA; Adresse:
  1022 First Street, Napa
• Beskæftigelse: 1923; Astronom
• Beskæftigelse: 1928, King, Washington, USA; Professor; Adresse:
  Seattle

Notater:

I kirken 5 may 1901.

Nekrolog:
Obituary: Theodore Siegumfeldt Jacobsen, 1901-2003
Kraft, Robert Paul; Wallerstein, George
Abstract: Theodor Jacobsen, oldest member of the American Astronomical Society, died in Seattle on 17 July 2003 at the age of 102. His astronomical career, which began in the 1920's, coincided with the rise of astronomy in the University of Washington from a one-man activity within mathematics to today's major astronomical department of more than 30 faculty and other research personnel.

Born on 6 February 1901 in Copenhagen, Denmark, he immigrated with his parents, brother and three sisters to the USA in 1917. Even while he was still in Denmark, his interest in astronomy was sparked at age 7 by a gift from his parents of a two-inch telescope. As early as 1921, in the midst of his undergraduate studies in chemistry at Stanford, he wrote to Director W. W. Campbell of Lick Observatory, inquiring how he should prepare for a career in astronomy and whether one could make a living at it. Campbell encouraged him to learn as much physics and mathematics as possible with the outcome that, on completion of his BA degree at Stanford, Jacobsen became a University of California Berkeley graduate student and was appointed a Lick Observatory fellow in the period 1923 to 1926. Following completion of his PhD thesis, entitled ``A Redetermination of the Radial Velocity Curves of Certain Cepheid Variable Stars" (LOB, 379, 1926), he was appointed as ``assistant" at Lick, a position roughly equivalent to that of ``instructor" in a modern University environment.
Inquiries concerning whether Lick could recommend ``a promising young man to take over teaching some astronomy and math" from then President Spencer of the University of Washington were received by Lick's acting director Robert Aitken in 1928. They were looking for a Berkeley PhD, said Spencer, and Aitken responded with an enthusiastic recommendation of Theodor Jacobsen, who then took up his duties in Seattle with the beginning of the fall term 1928. Jacobsen succeeded H. Zanstra (of Zanstra mechanism fame) in the Dept. of Mathematics, but it was not until 1948 that astronomy was split off from mathematics, at which time Jacobsen became chair and sole member of the new Astronomy Department. During the World War II years, he taught navigation to the recruits who moved on to become naval officers. In the postwar years, he taught elementary astronomy, as well as more advanced courses in practical astronomy, the kinds of subjects found in Smart's "Spherical Astronomy" text including celestial mechanics and observational work using the UW Observatory transit instrument. He chaired the Astronomy Department until 1965 when the Department began to undergo its modern expansion; he formally retired in 1971.
Jacobsen's post-thesis research continued to center on the determination of radial velocities of cepheids as well as binary stars and he maintained connections on a modest scale with the Dominion Astrophysical Observatory in Victoria, B.C. In this era of emphasis on galaxy evolution and cosmology, it is easy to forget that in the 1920s, there was still controversy over the nature of cepheids---were they pulsating stars or merely some form of odd binary? Jacobsen's extremely accurate radial velocity curves of these stars, when combined with then newly emerging accurate light curves, did much to bolster the pulsation hypothesis. According to astronomers currently working in the field, Jacobsen's 1926 velocity curves, obtained with the then state-of-the-art Mills spectrograph attached to the Lick 36-inch refractor, attained an impressive accuracy in the gamma velocities of these cepheids of about 100 m/s! His last paper on cepheid velocities was a joint publication in 1992, written when Jacobsen was more than 90 years old.
He also was a major contributor to the study of the ``level effect," a term applied to the fact that during the pulsation cycle, the radial velocity curves differ depending upon the spectral line formation depth within the cepheid atmospheres. The effect was recognized as a result of the passage of a running wave, again a manifestation of the pulsation phenomenon in cepheids.
Although the astronomy of stars was Jacobsen's main focus, he was a man of many interests. He had a love of the mountains, especially the nearby Cascade Range. He was especially fond of one-day hiking trips around and on the flanks of Mt Rainier, although he never attempted the strenuous climb to the summit. But some of the lesser summits of the Cascade range were among his trophies: Mt Hood in the late 40s, and Mt St. Helens in the 30s when because of its graceful symmetry, it was known as the ``Fujiyama of the West." He was also an accomplished pianist, his tastes running from Beethoven to the early romantics such as Schubert and Chopin. In many ways, his pianistic philosophy paralleled his personal attitudes about doing astronomy. For him, precision and clarity took precedence over lofty grand strategies. He was happy to make what he called modest additions to astronomical research, standing as it were, ``on the shoulders of others." Along with this, he would lament over, for example, how difficult it was to make the last movement of Beethoven's Op.27, No.2 clear---to make it effective, he would say, you have to pay attention to the details, just as doing good astronomy meant paying attention to the details.
Jacobsen married Evelyn Brandt a well-known Seattle piano teacher. They kept Welsh Corgi dogs, which they named for various famous astronomers. Theodor and Evelyn played together at facing grand pianos, sometimes works for duo piano, sometimes piano concertos with the orchestral part in piano transcription. All this came to an end in 1993 when Evelyn died after 40 years of marriage. They had no children.
Jacobsen remained interested in classical astronomy---that of the Greeks and Arabs---as a kind of hobby during his entire life. But it surprised some members of the UW astronomy faculty when they found, on visiting Jacobsen in his home in the mid-90s, an extensive manuscript that he had composed using modern mathematics to rederive the laws of planetary motions as conceived by the ancients using far more primitive means. With the help of these and other colleagues, he was able to publish, at the age of 98, a UW Press book entitled ``Planetary Systems from the Ancient Greeks to Kepler."
Publication: Bulletin of the American Astronomical Society, v. 35, no. 5, p. 1467-1468, Pub Date: December 2003 Bibcode: 2003BAAS...35.1467K

Udvandring:
US Naturalization 1921

Bopæl:
Student. Signalement: 5' 7", 130 pund, light complexion, brunt hår, blå øjne

Beskæftigelse:
US Census 1940: 4746, 16" N.E, Seattle:
Jacobsen, Theodor, Headm 39, S, Denmark, Professor, University
West, Lorris D, Partner, 21 S, Washington

Theodor blev gift med Evelyn L Brandt cirka 1953. Evelyn blev født i 1906; døde i 1993. [Gruppeskema] [Familietavle]

Andre Begivenheder og Egenskaber:

• Udvandring: 21 jun. 1917
• Beskæftigelse: 1928, King, Washington, USA; Lærer; Adresse:
  1629 38 Avenue, Seattle

Notater:

Levned:
Var gift med R. Wilson 1953 ved moderens død. Boede 1976 i Los Angeles.

Udvandring:
US naturalization Oct 1928.

Beskæftigelse:
Ved US Naturalization (se emigration): Piano Teacher. Ugift.

Begravet:
Gravsten afbildet. Sammen med ægtfællen.

Familie/Ægtefælle/Partner: Robert R. Wilson. Robert blev født den 9 jul. 1902; døde den 27 nov. 1982; blev begravet i 1982 i Santa Clara, Californien, USA. [Gruppeskema] [Familietavle]

Andre Begivenheder og Egenskaber:

• Beskæftigelse: Los Angeles, Californien, USA; Bibliotekar; Adresse:
  San Marino
• Titel: Ph.D.
• Udvandring: 1917
• Bopæl: 1936, Los Angeles, Californien, USA; Adresse:
  1325 Winston Avenue, San Marino

Notater:

Familien indrejst med fly fra Stockholm til New York 30 Oct 1948. Da forældrene med de to børn Erik og Hans.

Fødsel:
Tvilling til Esther Siegumdfeldt Jacobsen (d. 1904).

I kirken 28 August 1904.

Levned:
Omtalt og afbildet i YouTube-video: https://youtu.be/Auz-eHxXqLY (Dec 2020)

Beskæftigelse:
Huntington Library.

Titel:
Their mother was one of the first women to obtain a Ph.D. at Yale, and later worked as a librarian at the Huntington Library

Bopæl:
Mr. and Mrs, Albert Gregersen var vednier ved søsteren Elisabeths vielse.

Begravet:
Gravsten afbildet. Sammen med ægtfællen.

Familie/Ægtefælle/Partner: Albert Ingstrup Gregersen. Albert blev født den 20 feb. 1898 i Polk, Wisconsin, USA; døde den 7 maj 1978 i Santa Barbara, Californien, USA; blev begravet i 1978 i Santa Barbara, Californien, USA. [Gruppeskema] [Familietavle]

Andre Begivenheder og Egenskaber:

• Beskæftigelse: Dekoratør
• Udvandring: 1917
• Bopæl: 1976, Santa Barbara, Californien, USA

Notater:

Yderligere barn: Ellen Wilson (Gift Shiva)

I kirken 15 Oct 1911.

Beskæftigelse:
Interior decorator.

Bopæl:
1976, ved broderen Lydiks død, boede Lisse Lindman i Santa Barbara.

Begravet:
Gravsten afbildet. Alene.

Elisabeth blev gift med Guy Childers Wilson den 18 jun. 1936 i Los Angeles, Californien, USA. Guy blev født den 15 jul. 1898 i Californien, USA; døde den 18 apr. 1968 i Los Angeles, Californien, USA; blev begravet i 1968 i Santa Barbara, Californien, USA. [Gruppeskema] [Familietavle]

Erland blev gift med Nulevende [Gruppeskema] [Familietavle]

Familie/Ægtefælle/Partner: Nulevende. [Gruppeskema] [Familietavle]

Nulevende blev gift med Nulevende [Gruppeskema] [Familietavle]