11,041 research outputs found
An Appraisal of the Surface Geology and Sedimentary Processes within SEA7, the UK Continental Shelf
No full textMaximizing Research Impact Through Institutional and National Open-Access Self-Archiving Mandates
No full textNo research institution can afford all the journals its researchers may need, so all articles are losing research impact (usage and citations). Articles made “Open Access,” (OA) by self-archiving them on the web are cited twice as much, but only 15% of articles are being spontaneously self-archived. The only institutions approaching 100% self-archiving are those that mandate it. Surveys show that 95% of authors will comply with a self-archiving mandate; the actual expe-rience of institutions with mandates has confirmed this. What institutions and funders need to mandate is that (1) immediately upon acceptance for publication, (2) the author’s final draft must be (3) deposited into the Institutional Repository. Only the depositing needs to be mandated; set-ting access privileges to the full-text as either OA or Restricted Access (RA) can be left up to the author. For articles published in the 93% of journals that have already endorsed self-archiving, access can be set as OA immediately; for the remaining 7%, authors can email the eprint in re-sponse to individual email requests automatically forwarded by the Repository
Indoor 3D LIDAR scans with thermal images for mapping (the Automation Lab at Jacobs University Bremen)
No full textThis data set was recorded using a Riegl VZ-400 and a Optris PI IR camera. It contains several 3D scans taken around the Automation Lab at Jacobs University Bremen. The data set consists of scans and thermal images taken at different poses
Common Mode Currents in DC Power Routers
No full textThe grid reinforcement and energy redirection needs have led to the emergence of Back-To-Back Voltage Source Converter (BTB-VSC) based dc power routers. This paper investigates the low frequency Common Mode Currents (CMCs) that arise in the system if the employed BTB-VSCs have an un-isolated ac path connected in parallel to their output ports. Simulation results are presented to show a sensitivity analysis of lower order harmonics in CMC with respect to the operating active and reactive power of the dc router, dc link voltage, link resistance, modulation method and pole capacitance. Experimental results are shared to show existance of lower order CMC in 3-wire ac link operating in parallel with the dc power router and these are mitigated using zero sequence controller
Modeling, Control, and Operation of an M-DAB DC-DC Converter for Interconnection of HVDC Grids
No full textFuture high-voltage direct-current (HVDC) networks based on voltage source converters (VSCs) will have different structures (asymmetric monopolar, bipolar, or symmetric monopolar), voltage levels, control, and protection schemes. Therefore, dc-dc converters are needed to interconnect those VSC-HVDC grids and several technical issues on their control and operational systems must be adequately addressed. A dc-dc converter based on a modular-dual active bridge (M-DAB) converter is suggested to reach a desirable interconnection of the HVDC grids and regulate power flow (PF) between them. A dynamic averaged model is proposed for the M-DAB converter and its stability is analyzed using the Lyapunov function. Moreover, a new local controller based on nonlinear control theory is proposed for the M-DAB. The new M-DAB local controller is integrated with the energy management system (EMS), by updating the PF equations, to create a complete control structure. Considering the CIGRE DCS3 HVDC test system and the studied M-DAB, static, dynamic simulation, and experimental studies are conducted and the dc-dc converter and the performance of the designed controllers and the EMS are examined and validated.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Intelligent Electrical Power Grid
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Audit report: Bechtel Jacobs payroll creation
No full textThe Oak Ridge Operations Office (Operations Office) awarded a contract to the Bechtel Jacobs Company, LLC (Bechtel Jacobs) in December 1997. The terms of the contract require Bechtel Jacobs to create new jobs in the Oak Ridge area with a cumulative payroll of 11 million in new payroll. The objective of the audit was to determine if Bechtel Jacobs met its commitment to create at least 13.5 million in new payroll through September 30, 1998. In our opinion, the Department was not provided with sufficient data to fully verify that all claimed payroll had been created. The Operations Office verified that Bechtel National, Inc., and Jacobs Engineering Group Inc., created 8.6 million claimed by Bechtel Jacobs were letters from local companies showing the amount of new payroll claimed. The Operations Office did not require Bechtel Jacobs to obtain sufficiently detailed records to support the local companies' claims, and accepted the letters as adequate support. The Operations Office believed that company officials would not sign payroll creation claims unless the claims were true. As a result, the Department has little assurance that Bechtel Jacobs created 4.5 million in fee to which it was not contractually entitled
Randall Jacobs to Steven J. Owens, May 12, 1942
No full textA Western Union telegram from Rear Admiral Randall Jacobs, Chief of the Bureau of Navigation in the U.S. Navy to Steven J. Owens notifying the Owens family that his son, Samuel Owens is missing in action. Samuel Robert Owens (1918-1995) was stationed at Cavite Naval Yard in the Philippines when the United States entered World War II. He was a member of the crew of the submarine tender USS Canopus (AS-9), which was actively involved in the defense of the Bataan peninsula until the fall of Bataan on April 9, 1942. The majority of the crew of USS Canopus, including Owens, were captured by the Japanese at Corregidor, and became prisoners of war. Owens remained a POW until the end of the war and received the Silver Star and Bronze Star for his service.Class of Service
This is a full-rate
Telegram or Cablegram unless its deferred character is indicated by a suitable
symbol above or preceding the address.
WESTERN,
1220
* SYMBOLS ^
S*
DL=D«y Utter
NT - Overnight Telegram
LC=DeferredCable
NLT =CWe Night Letter
VER
^ Ship Radiogram f
The filing time shown in the date line on telegrams and day letters is STANDARD TIME at point of origin. Time .
}L0NG QE77 123 G0VT=WASHINGTON DC 12 210P
STEPHEN J OWENS*
••WEBSTER NCAR*
-THE NAVY DEPARTMENT EXCEEDINGLY REGRETS TO ADVISE YOU THAT
ACCORDING TO THE RECORDS OF THIS DEPARTMENT YOUR SON SAMEL
ROBERT OWENS TORPEDOMAN SECOND CLASS USN WAS PERFORMING HIS
DUTY IN THE SERVICE OF HIS COUNTRY IN THE MANILA BAY AREA
WHEN THAT STATION CAPITULATED X HE WILL BE CARRIED ON THE |
RECORDS OF THE NAVY DEPARTMENT AS MISSING PENDING FURTHER |
INFORMATION X-NO REPORT OF HIS DEATH OR INJURY HAS BEEN
RECEIVED AND HE MAY BE A PRISON OF WAR X IT WILL PROBABLY BE
SEVERAL MONTHS BEFORE DEFINITE OFFICIAL INFORMAT IONIAN BE
EXPECTED CONCERNING HIS STATUS X SINCERE SYMPATHY IS EXTENDEr
) TO YOU IN YOUR ANXIETY AND YOU ARE ASSURED THAT ANY REPORT
RECEIVED WILL BE COMMUNICATED TO YOU PROMPTLY X=
*RE~AR ADMIRAL RANDALL JACOBS CHIEF OF THE BUREAU OF
NAVIGATION:,
»X X X X Xse
APPRECIATE SUGGESTIONS FROM ITS PATRONS CONCERNING ITS SERVIC
Restructuring the existing medium voltage distribution grids using DC systems
No full textGreen Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.DC systems, Energy conversion & Storag
Cold cracking in DC-cast high strength aluminum alloy ingots: An intrinsic problem intensified by casting process parameters
No full textFor almost half a century the catastrophic failure of direct chill (DC) cast high strength aluminum alloys has been challenging the production of sound ingots. To overcome this problem, a criterion is required that can assist the researchers in predicting the critical conditions which facilitate the catastrophic failure of the ingots. This could be achieved at first glance by application of computer simulations to assess the level and distribution of residual thermal stresses. However, the simulation results are only able to show the critical locations and conditions where and when high stresses may appear in the ingots. The prediction of critical void/crack size requires simultaneous application of fracture mechanics. In this paper, we present the thermo-mechanical simulation results that indicate the critical crack size distribution in several DC-cast billets cast at various casting conditions. The simulation results were validated upon experimental DC-casting trials and revealed that the existence of voids/cracks with a considerable size is required for cold cracking to occur.Materials Science & EngineeringMechanical, Maritime and Materials Engineerin
A Dynamically Reconfigurable Recursive Switched-Capacitor DC-DC Converter with Adaptive Load Ability Enhancement
No full textMultiple voltage conversion ratio (VCR) recursive switched-capacitor (SC) dc-dc converters, based on several basic 2:1 converters, are widely used for on-chip power supplies due to their flexible VCRs for higher energy efficiency. However, conventional multiple VCR SC converters usually have one or more 2:1 converters unused for some VCRs, which results in lower power density and chip area wastage. This article presents a new recursive dc-dc converter system, which can dynamically reconfigure the connection of all on-chip 2:1 converter cells so that the unused converters in the conventional designs can be reused in this new architecture for increasing the load-driving capacity, power density, and power efficiency. To validate the design, a 4-bit-input 15-ratio system was designed and fabricated in a 180-nm BCD process, which can support a maximum load current of \text{0.71}\,\text{mA} and achieves a peak power efficiency of 93.1% with 105.3\,\mu \text{A/mm} {2} chip power density from a 2-V input power supply. The measurement results show that the load-driving capacity can become 6.826×, 2.236×, and 2.175× larger than the conventional topology when the VCR is 1/2, 1/4, and 3/4, respectively. In addition, the power efficiency under these specific VCRs can also be improved considerably.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Electronic Instrumentatio
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