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Hayes AG, Corlies P, Tate C, Barrington M, Bell JF, Maki JN, Caplinger M, Ravine M, Kinch KM, Herkenhoff K, Horgan B, Johnson J, Lemmon M, Paar G, Rice MS, Jensen E, Kubacki TM, Cloutis E, Deen R, Ehlmann BL, Lakdawalla E, Sullivan R, Winhold A, Parkinson A, Bailey Z, van Beek J, Caballo-Perucha P, Cisneros E, Dixon D, Donaldson C, Jensen OB, Kuik J, Lapo K, Magee A, Merusi M, Mollerup J, Scudder N, Seeger C, Stanish E, Starr M, Thompson M, Turenne N, Winchell K. Pre-Flight Calibration of the Mars 2020 Rover Mastcam Zoom (Mastcam-Z) Multispectral, Stereoscopic Imager. Space Sci Rev 2021; 217:29. [PMID: 33678912 PMCID: PMC7892537 DOI: 10.1007/s11214-021-00795-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 01/12/2021] [Indexed: 05/28/2023]
Abstract
UNLABELLED The NASA Perseverance rover Mast Camera Zoom (Mastcam-Z) system is a pair of zoomable, focusable, multi-spectral, and color charge-coupled device (CCD) cameras mounted on top of a 1.7 m Remote Sensing Mast, along with associated electronics and two calibration targets. The cameras contain identical optical assemblies that can range in focal length from 26 mm ( 25.5 ∘ × 19.1 ∘ FOV ) to 110 mm ( 6.2 ∘ × 4.2 ∘ FOV ) and will acquire data at pixel scales of 148-540 μm at a range of 2 m and 7.4-27 cm at 1 km. The cameras are mounted on the rover's mast with a stereo baseline of 24.3 ± 0.1 cm and a toe-in angle of 1.17 ± 0.03 ∘ (per camera). Each camera uses a Kodak KAI-2020 CCD with 1600 × 1200 active pixels and an 8 position filter wheel that contains an IR-cutoff filter for color imaging through the detectors' Bayer-pattern filters, a neutral density (ND) solar filter for imaging the sun, and 6 narrow-band geology filters (16 total filters). An associated Digital Electronics Assembly provides command data interfaces to the rover, 11-to-8 bit companding, and JPEG compression capabilities. Herein, we describe pre-flight calibration of the Mastcam-Z instrument and characterize its radiometric and geometric behavior. Between April 26 t h and May 9 t h , 2019, ∼45,000 images were acquired during stand-alone calibration at Malin Space Science Systems (MSSS) in San Diego, CA. Additional data were acquired during Assembly Test and Launch Operations (ATLO) at the Jet Propulsion Laboratory and Kennedy Space Center. Results of the radiometric calibration validate a 5% absolute radiometric accuracy when using camera state parameters investigated during testing. When observing using camera state parameters not interrogated during calibration (e.g., non-canonical zoom positions), we conservatively estimate the absolute uncertainty to be < 10 % . Image quality, measured via the amplitude of the Modulation Transfer Function (MTF) at Nyquist sampling (0.35 line pairs per pixel), shows MTF Nyquist = 0.26 - 0.50 across all zoom, focus, and filter positions, exceeding the > 0.2 design requirement. We discuss lessons learned from calibration and suggest tactical strategies that will optimize the quality of science data acquired during operation at Mars. While most results matched expectations, some surprises were discovered, such as a strong wavelength and temperature dependence on the radiometric coefficients and a scene-dependent dynamic component to the zero-exposure bias frames. Calibration results and derived accuracies were validated using a Geoboard target consisting of well-characterized geologic samples. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s11214-021-00795-x.
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Affiliation(s)
- Alexander G. Hayes
- Department of Astronomy, Cornell University, Ithaca, NY 14850 USA
- Cornell Center for Astrophysics and Planetary Science, Cornell University, Ithaca, NY 14850 USA
| | - P. Corlies
- Department of Astronomy, Cornell University, Ithaca, NY 14850 USA
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - C. Tate
- Department of Astronomy, Cornell University, Ithaca, NY 14850 USA
| | - M. Barrington
- Department of Astronomy, Cornell University, Ithaca, NY 14850 USA
| | - J. F. Bell
- School of Earth and Space Exploration, Arizona State University, Phoenix, AZ 85287 USA
| | - J. N. Maki
- Jet Propulsion Laboratory, Pasadena, CA 91109 USA
| | - M. Caplinger
- Malin Space Science Systems, San Diego, CA 92121 USA
| | - M. Ravine
- Malin Space Science Systems, San Diego, CA 92121 USA
| | - K. M. Kinch
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - K. Herkenhoff
- USGS Astrogeology Science Center, 2255 N. Gemini Drive, Flagstaff, AZ 86001 USA
| | - B. Horgan
- Earth, Atmospheric, and Planetary Sciences Department, Purdue University, West Lafayette, IN 47907 USA
| | - J. Johnson
- Johns Hopkins Applied Physics Laboratory, Laurel, MD 20723 USA
| | - M. Lemmon
- Space Science Institute, 4765 Walnut St., Suite B, Boulder, CO 80301 USA
| | - G. Paar
- Joanneum Research Forschungsgesellschaft mbH, Steyrergasse 17, 8010 Graz, Austria
| | - M. S. Rice
- Geology Department, Western Washington University, Bellingham, WA 98225 USA
| | - E. Jensen
- Malin Space Science Systems, San Diego, CA 92121 USA
| | - T. M. Kubacki
- Malin Space Science Systems, San Diego, CA 92121 USA
| | - E. Cloutis
- Geography Department, University of Winnepeg, 515 Portage Ave, Winnipeg, MB R3B 2E9 Canada
| | - R. Deen
- Jet Propulsion Laboratory, Pasadena, CA 91109 USA
| | - B. L. Ehlmann
- Jet Propulsion Laboratory, Pasadena, CA 91109 USA
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91101 USA
| | - E. Lakdawalla
- The Planetary Society, 60 S Los Robles, Pasadena, CA 91101 USA
| | - R. Sullivan
- Cornell Center for Astrophysics and Planetary Science, Cornell University, Ithaca, NY 14850 USA
| | - A. Winhold
- School of Earth and Space Exploration, Arizona State University, Phoenix, AZ 85287 USA
| | - A. Parkinson
- Centre for Terrestrial and Planetary Exploration, University of Winnipeg, 515 Portage Ave, Winnipeg, MB R3B 2E9 Canada
| | - Z. Bailey
- Jet Propulsion Laboratory, Pasadena, CA 91109 USA
| | - J. van Beek
- Jet Propulsion Laboratory, Pasadena, CA 91109 USA
| | - P. Caballo-Perucha
- Joanneum Research Forschungsgesellschaft mbH, Steyrergasse 17, 8010 Graz, Austria
| | - E. Cisneros
- School of Earth and Space Exploration, Arizona State University, Phoenix, AZ 85287 USA
| | - D. Dixon
- Malin Space Science Systems, San Diego, CA 92121 USA
| | - C. Donaldson
- Malin Space Science Systems, San Diego, CA 92121 USA
| | - O. B. Jensen
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - J. Kuik
- Centre for Terrestrial and Planetary Exploration, University of Winnipeg, 515 Portage Ave, Winnipeg, MB R3B 2E9 Canada
| | - K. Lapo
- Geology Department, Western Washington University, Bellingham, WA 98225 USA
| | - A. Magee
- Malin Space Science Systems, San Diego, CA 92121 USA
| | - M. Merusi
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - J. Mollerup
- Geology Department, Western Washington University, Bellingham, WA 98225 USA
| | - N. Scudder
- Earth, Atmospheric, and Planetary Sciences Department, Purdue University, West Lafayette, IN 47907 USA
| | - C. Seeger
- Geology Department, Western Washington University, Bellingham, WA 98225 USA
| | - E. Stanish
- Centre for Terrestrial and Planetary Exploration, University of Winnipeg, 515 Portage Ave, Winnipeg, MB R3B 2E9 Canada
| | - M. Starr
- Malin Space Science Systems, San Diego, CA 92121 USA
| | - M. Thompson
- Jet Propulsion Laboratory, Pasadena, CA 91109 USA
| | - N. Turenne
- Centre for Terrestrial and Planetary Exploration, University of Winnipeg, 515 Portage Ave, Winnipeg, MB R3B 2E9 Canada
| | - K. Winchell
- Malin Space Science Systems, San Diego, CA 92121 USA
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Maki JN, Gruel D, McKinney C, Ravine MA, Morales M, Lee D, Willson R, Copley-Woods D, Valvo M, Goodsall T, McGuire J, Sellar RG, Schaffner JA, Caplinger MA, Shamah JM, Johnson AE, Ansari H, Singh K, Litwin T, Deen R, Culver A, Ruoff N, Petrizzo D, Kessler D, Basset C, Estlin T, Alibay F, Nelessen A, Algermissen S. The Mars 2020 Engineering Cameras and Microphone on the Perseverance Rover: A Next-Generation Imaging System for Mars Exploration. Space Sci Rev 2020; 216:137. [PMID: 33268910 PMCID: PMC7686239 DOI: 10.1007/s11214-020-00765-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 11/09/2020] [Indexed: 05/16/2023]
Abstract
The Mars 2020 Perseverance rover is equipped with a next-generation engineering camera imaging system that represents an upgrade over previous Mars rover missions. These upgrades will improve the operational capabilities of the rover with an emphasis on drive planning, robotic arm operation, instrument operations, sample caching activities, and documentation of key events during entry, descent, and landing (EDL). There are a total of 16 cameras in the Perseverance engineering imaging system, including 9 cameras for surface operations and 7 cameras for EDL documentation. There are 3 types of cameras designed for surface operations: Navigation cameras (Navcams, quantity 2), Hazard Avoidance Cameras (Hazcams, quantity 6), and Cachecam (quantity 1). The Navcams will acquire color stereo images of the surface with a 96 ∘ × 73 ∘ field of view at 0.33 mrad/pixel. The Hazcams will acquire color stereo images of the surface with a 136 ∘ × 102 ∘ at 0.46 mrad/pixel. The Cachecam, a new camera type, will acquire images of Martian material inside the sample tubes during caching operations at a spatial scale of 12.5 microns/pixel. There are 5 types of EDL documentation cameras: The Parachute Uplook Cameras (PUCs, quantity 3), the Descent stage Downlook Camera (DDC, quantity 1), the Rover Uplook Camera (RUC, quantity 1), the Rover Descent Camera (RDC, quantity 1), and the Lander Vision System (LVS) Camera (LCAM, quantity 1). The PUCs are mounted on the parachute support structure and will acquire video of the parachute deployment event as part of a system to characterize parachute performance. The DDC is attached to the descent stage and pointed downward, it will characterize vehicle dynamics by capturing video of the rover as it descends from the skycrane. The rover-mounted RUC, attached to the rover and looking upward, will capture similar video of the skycrane from the vantage point of the rover and will also acquire video of the descent stage flyaway event. The RDC, attached to the rover and looking downward, will document plume dynamics by imaging the Martian surface before, during, and after rover touchdown. The LCAM, mounted to the bottom of the rover chassis and pointed downward, will acquire 90 ∘ × 90 ∘ FOV images during the parachute descent phase of EDL as input to an onboard map localization by the Lander Vision System (LVS). The rover also carries a microphone, mounted externally on the rover chassis, to capture acoustic signatures during and after EDL. The Perseverance rover launched from Earth on July 30th, 2020, and touchdown on Mars is scheduled for February 18th, 2021.
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Affiliation(s)
- J. N. Maki
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - D. Gruel
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - C. McKinney
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | | | - M. Morales
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - D. Lee
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - R. Willson
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - D. Copley-Woods
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - M. Valvo
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - T. Goodsall
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - J. McGuire
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - R. G. Sellar
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | | | | | | | - A. E. Johnson
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - H. Ansari
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - K. Singh
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - T. Litwin
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - R. Deen
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - A. Culver
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - N. Ruoff
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - D. Petrizzo
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - D. Kessler
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - C. Basset
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - T. Estlin
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - F. Alibay
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - A. Nelessen
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
| | - S. Algermissen
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA
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Golombek M, Williams N, Warner NH, Parker T, Williams MG, Daubar I, Calef F, Grant J, Bailey P, Abarca H, Deen R, Ruoff N, Maki J, McEwen A, Baugh N, Block K, Tamppari L, Call J, Ladewig J, Stoltz A, Weems WA, Mora‐Sotomayor L, Torres J, Johnson M, Kennedy T, Sklyanskiy E. Location and Setting of the Mars InSight Lander, Instruments, and Landing Site. Earth Space Sci 2020; 7:e2020EA001248. [PMID: 33134434 PMCID: PMC7583488 DOI: 10.1029/2020ea001248] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 09/09/2020] [Accepted: 09/12/2020] [Indexed: 06/11/2023]
Abstract
Knowing precisely where a spacecraft lands on Mars is important for understanding the regional and local context, setting, and the offset between the inertial and cartographic frames. For the InSight spacecraft, the payload of geophysical and environmental sensors also particularly benefits from knowing exactly where the instruments are located. A ~30 cm/pixel image acquired from orbit after landing clearly resolves the lander and the large circular solar panels. This image was carefully georeferenced to a hierarchically generated and coregistered set of decreasing resolution orthoimages and digital elevation models to the established positive east, planetocentric coordinate system. The lander is located at 4.502384°N, 135.623447°E at an elevation of -2,613.426 m with respect to the geoid in Elysium Planitia. Instrument locations (and the magnetometer orientation) are derived by transforming from Instrument Deployment Arm, spacecraft mechanical, and site frames into the cartographic frame. A viewshed created from 1.5 m above the lander and the high-resolution orbital digital elevation model shows the lander is on a shallow regional slope down to the east that reveals crater rims on the east horizon ~400 m and 2.4 km away. A slope up to the north limits the horizon to about 50 m away where three rocks and an eolian bedform are visible on the rim of a degraded crater rim. Azimuths to rocks and craters identified in both surface panoramas and high-resolution orbital images reveal that north in the site frame and the cartographic frame are the same (within 1°).
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Affiliation(s)
- M. Golombek
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - N. Williams
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - N. H. Warner
- Department of Geological SciencesSUNY GeneseoGeneseoNYUSA
| | - T. Parker
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - M. G. Williams
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - I. Daubar
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
- Department of Earth, Environmental, and Planetary SciencesBrown UniversityProvidenceRIUSA
| | - F. Calef
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - J. Grant
- Smithsonian Institution, National Air and Space MuseumWashingtonDCUSA
| | - P. Bailey
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - H. Abarca
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - R. Deen
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - N. Ruoff
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - J. Maki
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - A. McEwen
- Lunar and Planetary LaboratoryUniversity of ArizonaTucsonAZUSA
| | - N. Baugh
- Lunar and Planetary LaboratoryUniversity of ArizonaTucsonAZUSA
| | - K. Block
- Lunar and Planetary LaboratoryUniversity of ArizonaTucsonAZUSA
| | - L. Tamppari
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - J. Call
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | | | | | | | - L. Mora‐Sotomayor
- Centro de Astrobiología (CSIC/INTA)Instituto Nacional de Técnica AeroespacialMadridSpain
| | - J. Torres
- Centro de Astrobiología (CSIC/INTA)Instituto Nacional de Técnica AeroespacialMadridSpain
| | | | | | - E. Sklyanskiy
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
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Chan KK, Dassanayake B, Deen R, Wickramarachchi RE, Kumarage SK, Samita S, Deen KI. Young patients with colorectal cancer have poor survival in the first twenty months after operation and predictable survival in the medium and long-term: analysis of survival and prognostic markers. World J Surg Oncol 2010; 8:82. [PMID: 20840793 PMCID: PMC2954852 DOI: 10.1186/1477-7819-8-82] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2010] [Accepted: 09/15/2010] [Indexed: 12/14/2022] Open
Abstract
Objectives This study compares clinico-pathological features in young (<40 years) and older patients (>50 years) with colorectal cancer, survival in the young and the influence of pre-operative clinical and histological factors on survival. Materials and methods A twelve year prospective database of colorectal cancer was analysed. Fifty-three young patients were compared with forty seven consecutive older patients over fifty years old. An analysis of survival was undertaken in young patients using Kaplan Meier graphs, non parametric methods, Cox's Proportional Hazard Ratios and Weibull Hazard models. Results Young patients comprised 13.4 percent of 397 with colorectal cancer. Duration of symptoms and presentation in the young was similar to older patients (median, range; young patients; 6 months, 2 weeks to 2 years, older patients; 4 months, 4 weeks to 3 years, p > 0.05). In both groups, the majority presented without bowel obstruction (young - 81%, older - 94%). Cancer proximal to the splenic flexure was present more in young than in older patients. Synchronous cancers were found exclusively in the young. Mucinous tumours were seen in 16% of young and 4% of older patients (p < 0.05). Ninety four percent of young cancer deaths were within 20 months of operation. At median follow up of 50 months in the young, overall survival was 70% and disease free survival 66%. American Joint Committee on Cancer (AJCC) stage 4 and use of pre-operative chemoradiation in rectal cancer was associated with poor survival in the young. Conclusion If patients, who are less than 40 years old with colorectal cancer, survive twenty months after operation, the prognosis improves and their survival becomes predictable.
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Affiliation(s)
- K K Chan
- The Johor Bahru Hospital, Johor, Malaysia
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Maki JN, Bell JF, Herkenhoff KE, Squyres SW, Kiely A, Klimesh M, Schwochert M, Litwin T, Willson R, Johnson A, Maimone M, Baumgartner E, Collins A, Wadsworth M, Elliot ST, Dingizian A, Brown D, Hagerott EC, Scherr L, Deen R, Alexander D, Lorre J. Mars Exploration Rover Engineering Cameras. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2003je002077] [Citation(s) in RCA: 141] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- J. N. Maki
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - J. F. Bell
- Department of Astronomy; Cornell University; Ithaca New York USA
| | - K. E. Herkenhoff
- Astrogeology Team; United States Geological Survey; Flagstaff Arizona USA
| | - S. W. Squyres
- Department of Astronomy; Cornell University; Ithaca New York USA
| | - A. Kiely
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - M. Klimesh
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - M. Schwochert
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - T. Litwin
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - R. Willson
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - A. Johnson
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - M. Maimone
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - E. Baumgartner
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - A. Collins
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - M. Wadsworth
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - S. T. Elliot
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - A. Dingizian
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - D. Brown
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - E. C. Hagerott
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - L. Scherr
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - R. Deen
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - D. Alexander
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
| | - J. Lorre
- Jet Propulsion Laboratory; California Institute of Technology; Pasadena California USA
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Dalpiaz P, Deen R, Deitz R, Doyle J, Duke MP, Niswander G, Winstead D. New directions in materials management ... dialog. Hosp Top 1985; 63:12-21, 31. [PMID: 10273791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Today, the VHA stands as the country's largest hospital purchasing program, representing hospitals that purchase over $1.5 billion in supplies each year. But not all of that comes through VHA programs, and it is in the relationship between the individual institutions and the VHA system, that the group draws its strength and discovers its limitations. At once highly sophisticated and fiercely independent, the materials managers that make up the VHA program must weigh the significant opportunities inherent in the group's size and scope against the individual demands of their institutions. Mutual understanding leads to consensus and eventually to commitment and out of that process comes a number of highly innovative programs, such as standardization and single sourcing and the VHA Plus private label program, that are helping to make the VHA not simply the country's leading purchasing organization, but its most innovative as well--a true materials management system.
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Affiliation(s)
- A J. Hoff
- Laboratory of Physiological Chemistry, University of Leiden, The Netherlands
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