The role of hydroelectric generation in electric power systems with large scale wind generation

Thesis (S.M. in Technology and Policy)-- Massachusetts Institute of Technology, Engineering Systems Division, Technology and Policy Program, 2012.Cataloged from PDF version of thesis.Includes bibliographical references (p. 123-126).An increasing awareness of the operational challenges created by intermittent generation of electricity from policy-mandated renewable resources, such as wind and solar, has led to increased scrutiny of the public policies that promote their growth and the regulatory system that maintains operation of a reliable and economically efficient power system. Anecdotal evidence has suggested that hydroelectric generation can provide significant benefits in power systems that have already significantly increased their power generation from intermittent renewable resources. A heuristic-based algorithm for optimizing the scheduling of hydroelectric power generation facilities was developed and integrated into the Low-Emissions Electricity Market Analysis (LEEMA) model to analyze the interaction of generation capacity from wind, thermal, and hydro resources in the economic dispatch of individual generation plants. The algorithm identifies the most costly periods of thermal production, considering fuel, startup and operation and maintenance costs, to determine the optimal schedule of hydro generation within its capacity constraints. The hydrothermal LEEMA model is run on the current Spanish electric power system to identify the impact of introducing hydro generation to a system, varying levels of flexibility in hydro generation, and increasing levels of wind generation. The analysis concludes that hydro generation can significantly reduce the impact of intermittent renewable generation, that the level of flexibility of hydro generation must be understood to determine how beneficial the hydro generation can be, and that hydro generation will delay the most significant impacts of increasing levels of wind generation.by John Michael Hagerty.S.M.in Technology and Polic

Research and education in management of large-scale technical programs

A research effort is reported which was conducted by NASA in conjunction with Drexel University, and which was aimed at an improved understanding of large scale systems technology and management

Rising happiness in nations,1946-2004. A reply to Easterlin

ABSTRACT The ‘Easterlin paradox’ holds that economic growth does not add to the quality-of-life and that this appears in the fact that average happiness in nations has not risen in the last few decades. The latest trend data show otherwise. Average happiness has increased slightly in rich nations and considerably in the few poor nations for which data are available. Since longevity has also increased, the average number of happy life years has increased at an unprecedented rate since the 1950s

Gyroscopically Stabilized Oscillators and Heat Baths

In this paper we analyze the stability of a gyroscopic oscillator interacting with a finite- and infinite-dimensional heat bath in both the classical and quantum cases. We consider a finite gyroscopic oscillator model of a particle on a rotating disc and a particle in a magnetic field and we examine stability before and after coupling to a heat bath. The heat bath is modelled in the finite-dimensional setting by a system of independent oscillators with mass. It is shown that if the oscillator is gyroscopically stable, coupling to a sufficiently massive heat bath induces instability even in the finite-dimensional setting. The key mechanism for instability in this paper is thus not induced by damping. The meaning of these ideas in the quantum context is discussed. The model extends the exact diagonalization analysis of an oscillator and field of Ford, Lewis, and O'Connell to the gyroscopic setting. We also discuss the interesting role that damping of Landau type plays in the infinite limit.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45132/1/10955_2004_Article_481221.pd

Case Study of Ecstatic Meditation: fMRI and EEG Evidence of Self-Stimulating a Reward System

We report the first neural recording during ecstatic meditations called jhanas and test whether a brain reward system plays a role in the joy reported. Jhanas are Altered States of Consciousness (ASC) that imply major brain changes based on subjective reports: (1) external awareness dims, (2) internal verbalizations fade, (3) the sense of personal boundaries is altered, (4) attention is highly focused on the object of meditation, and (5) joy increases to high levels. The fMRI and EEG results from an experienced meditator show changes in brain activity in 11 regions shown to be associated with the subjective reports, and these changes occur promptly after jhana is entered. In particular, the extreme joy is associated not only with activation of cortical processes but also with activation of the nucleus accumbens (NAc) in the dopamine/opioid reward system. We test three mechanisms by which the subject might stimulate his own reward system by external means and reject all three. Taken together, these results demonstrate an apparently novel method of self-stimulating a brain reward system using only internal mental processes in a highly trained subject

Emricasan (IDN-6556) Lowers Portal Pressure in Patients with Compensated Cirrhosis and Severe Portal Hypertension

Caspases play a central role in apoptosis, inflammation and fibrosis. They produce hemodynamically-active, pro-inflammatory microparticles that cause intrahepatic inflammation, vasoconstriction and extrahepatic splanchnic vasodilation. Emricasan is a pan-caspase inhibitor that lowers portal hypertension (PH) and improves survival in murine models of cirrhosis. This exploratory study assessed whether emricasan lowers PH in patients with compensated cirrhosis. This multicenter, open-label study enrolled 23 subjects with compensated cirrhosis and PH (HVPG >5 mmHg). Emricasan 25 mg BID was given for 28 days. HVPG measurements were standardized and performed before and after emricasan. A single expert read all HVPG tracings.Median age was 59 (range 49-80); 70% were male. Cirrhosis etiologies were NASH and HCV. Subjects were Child class A (87%) with median MELD score of 8 (range 6-15). Twelve had severe PH (HVPG?12mmHg). Overall, there was no significant change in HVPG after emricasan (mean [SD] -1.1[4.57] mmHg). HVPG decreased significantly (mean [SD] -3.7[4.05] mmHg; p=0.003) in those with severe PH. 4/12 had a ?20% decrease; 8/12 had a ?10% decrease; and 2/12 HVPG decreased below 12mmHg. There were no significant changes in blood pressure or heart rate. AST/ALT decreased significantly in the entire group and in severe PH. Serum cCK18 and caspase-3/7 decreased significantly. Emricasan was well-tolerated. One subject discontinued for non-serious adverse events.Emricasan administered for 28 days decreased HVPG in patients with compensated cirrhosis and severe PH. An effect upon portal venous inflow is likely and concomitant decreases in AST/ALT suggest an intrahepatic anti-inflammatory effect

The Canberra Commission: Paths Followed, Paths Ahead

Despite its inauspicious start and virtual abandonment by the new Coalition government in Australia, the Canberra Commission on the Elimination of Nuclear Weapons continued to attract international attention in arms control and disarmament circles