Institution
University of Massachusetts Amherst
Education•Amherst Center, Massachusetts, United States•
About: University of Massachusetts Amherst is a education organization based out in Amherst Center, Massachusetts, United States. It is known for research contribution in the topics: Population & Galaxy. The organization has 37274 authors who have published 83965 publications receiving 3834996 citations. The organization is also known as: UMass Amherst & Massachusetts State College.
Papers published on a yearly basis
Papers
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TL;DR: A new technique for feeding printed antennas is described in this paper, where a microstrip antenna on one substrate is coupled to a microstripline feed on another parallel substrate through an aperture in the ground plane which separates the two substrates.
Abstract: A new technique for feeding printed antennas is described A microstrip antenna on one substrate is coupled to a microstripline feed on another parallel substrate through an aperture in the ground plane which separates the two substrates A simple theory explaining the coupling mechanism is presented, as well as measurements of a prototype aperture-fed antenna
860 citations
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TL;DR: A recently developed dynamic model of TCP congestion-avoidance mode relates key network parameters such as the number of TCP sessions, link capacity and round-trip time to the underlying feedback control problem and analyzes the present de facto AQM standard: random early detection (RED) and determines that REDs queue-averaging is not beneficial.
Abstract: In active queue management (AQM), core routers signal transmission control protocol (TCP) sources with the objective of managing queue utilization and delay. It is essentially a feedback control problem. Based on a recently developed dynamic model of TCP congestion-avoidance mode, this paper does three things: 1) it relates key network parameters such as the number of TCP sessions, link capacity and round-trip time to the underlying feedback control problem; 2) it analyzes the present de facto AQM standard: random early detection (RED) and determines that REDs queue-averaging is not beneficial; and 3) it recommends alternative AQM schemes which amount to classical proportional and proportional-integral control. We illustrate our results using ns simulations and demonstrate the practical impact of proportional-integral control on managing queue utilization and delay.
858 citations
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TL;DR: In spite of the higher cell yields obtained with octanoate and nonanoate, the use of hexanoates and heptanoate yielded higher-molecular-weight polymers, which represent an entirely new class of biodegradable thermoplastics.
Abstract: Pseudomonas oleovorans was grown in homogeneous media containing n-alkanoic acids, from formate to decanoate, as the sole carbon sources. Formation of intracellular poly(β-hydroxyalkanoates) was observed only for hexanoate and the higher n-alkanoic acids. The maximum isolated polymer yields were approximately 30% of the cellular dry weight with growth on either octanoate or nonanoate. In most cases, the major repeating unit in the polymer had the same chain length as the n-alkanoic acid used for growth, but units with two carbon atoms less or more than the acid used as a carbon source were also generally present in the polyesters formed. Indeed, copolymers containing as many as six different types of β-hydroxyalkanoate units were formed. The weight average molecular weights of the poly(β-hydroxyalkanoate) copolymers produced by P. oleovorans ranged from 90,000 to 370,000. In spite of the higher cell yields obtained with octanoate and nonanoate, the use of hexanoate and heptanoate yielded higher-molecular-weight polymers. These copolyesters represent an entirely new class of biodegradable thermoplastics.
856 citations
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TL;DR: A core (sub)set of metrics are proposed, identified through literature reviews, which are understood as the most useful and relevant for landscape planning, and a two-part sustainable landscape planning perspective is proposed, integrating horizontal and vertical perspectives.
855 citations
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TL;DR: The authors of as mentioned in this paper showed that approximately 30%-40% of all baryons in the present-day universe reside in a warm-hot intergalactic medium (WHIM), with temperatures in the range 105 < T < 107 K. This is a generic prediction from six hydrodynamic simulations of currently favored structure formation models having a wide variety of numerical methods, input physics, volumes, and spatial resolutions.
Abstract: Approximately 30%-40% of all baryons in the present-day universe reside in a warm-hot intergalactic medium (WHIM), with temperatures in the range 105 < T < 107 K. This is a generic prediction from six hydrodynamic simulations of currently favored structure formation models having a wide variety of numerical methods, input physics, volumes, and spatial resolutions. Most of these warm-hot baryons reside in diffuse large-scale structures with a median overdensity around 10-30, not in virialized objects such as galaxy groups or galactic halos. The evolution of the WHIM is primarily driven by shock heating from gravitational perturbations breaking on mildly nonlinear, nonequilibrium structures such as filaments. Supernova feedback energy and radiative cooling play lesser roles in its evolution. WHIM gas may be consistent with observations of the 0.25 keV X-ray background without being significantly heated by nongravitational processes because the emitting gas is very diffuse. Our results confirm and extend previous work by Cen & Ostriker and Dave et al.
854 citations
Authors
Showing all 37601 results
Name | H-index | Papers | Citations |
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George M. Whitesides | 240 | 1739 | 269833 |
Joan Massagué | 189 | 408 | 149951 |
David H. Weinberg | 183 | 700 | 171424 |
David L. Kaplan | 177 | 1944 | 146082 |
Michael I. Jordan | 176 | 1016 | 216204 |
James F. Sallis | 169 | 825 | 144836 |
Bradley T. Hyman | 169 | 765 | 136098 |
Anton M. Koekemoer | 168 | 1127 | 106796 |
Derek R. Lovley | 168 | 582 | 95315 |
Michel C. Nussenzweig | 165 | 516 | 87665 |
Alfred L. Goldberg | 156 | 474 | 88296 |
Donna Spiegelman | 152 | 804 | 85428 |
Susan E. Hankinson | 151 | 789 | 88297 |
Bernard Moss | 147 | 830 | 76991 |
Roger J. Davis | 147 | 498 | 103478 |