Short-term Utility Research Articles

Electric power planning for regulated and deregulated markets

Preface. Acknowledgments. Figure Citations. About the Author. 1. Overview. 1.1 The Power Delivery Chain in a Vertically Integrated Utility. 1.2 The Power Delivery Chain in a Market Environment. 2. Energy, Load, and Generation Technologies. 2.1 Energy, Power, and their Measurements. 2.2 Load. 2.3 Generation Technologies. 3. The Grid. 3.1 Fundamentals: Load, Generation, and Alternating Current. 3.2 Grid Equipment. 3.3 Grid Reliability and Contingency Requirements. 3.4 Grid Confi guration. 3.5 Grid Operations. 3.6 Blackout August 14, 2003. 4. Short-Term Utility Planning. 4.1 Planning and Execution of Dispatch: Day-Ahead Planning Through Real-Time Delivery. 4.2 Day-Ahead Demand Forecasting: Load and Ancillary Service Requirements. 4.3 Least-Cost Dispatch in a Single Control Area: A Simple Model. 4.4 A Solution Using Profi t Maximization. 4.5 Least-Cost Dispatch in a Single Control Area with Operating Constraints. 4.6 Least-Cost Dispatch in a Single Node with Spinning Reserve and Regulation. 4.7 Least-Cost Dispatch in a Network. 4.8 Real Time. 5. Long-Term Utility Planning. 5.1 Project Development. 5.2 The Planning Process. 5.3 Long-Term Load Forecasting. 5.4 A Simplifi ed Look at Generation Capacity Additions. 5.5 Generation Additions and Retirements Within a Single Control Area. 5.6 Generation Additions and Retirements with Transmission to a Single Control Area. 5.7 Generation Additions and Retirements and Transmission Additions Within a Network. 5.8 Reserve Reuqirements. 6. Midterm Utility Planning. 6.1 Informational Requirements. 6.2 Formulation of the Optimization Problem. 7. A Market Environment. 7.1 Principles and Architecture. 7.2 Short-Term Market Design: Day-Ahead Scheduling Through Real-Time Delivery. 7.3 Long-Term Market Design: No Clear Solutions. 7.4 Midterm Market Design. 8. Asset Management in Short-Term Markets. 8.1 Retailers. 8.2 Power Producers. 8.3 Integrated Energy Companies. 9. Investment Analysis: Long-Term Planning in a Market Environment. 9.1 Investment Setting in Utility and Market Environments. 9.2 Project Analysis for a Merchant Plant. 9.3 Power Purchase Agreements (Long-Term Contracts). 10. Risk Management in the Midterm Markets. 10.1 Retailer Risk. 10.2 Power Producer Risk. 10.3 A Quick Risk Primer in Statistics for Risk Management. 10.4 Risk Management in Midterm Markets: Retailers. 10.5 Risk Management in Midterm Markets: Power Producers. 10.6 Risk Management in Midterm Markets: Integrated Electricity Suppliers. 11. The California Experience. 11.1 Market Fundamentals. 11.2 Short-Term Market Structure: The CALPX, CAISO, and Other Market Participants. 11.3 Fatboy, Get Shorty, Ricochet, and Death Star. 11.4 Market Contrast: PJM and California. Bibliography. Index.

Using Inquiry-Based Methodologies to Ease the Pain of Learning Mineral Formulae and Analytical Techniques

Learning (memorizing) mineral formulae and analytical techniques and procedures can represent two of the more odious tasks facing students in Mineralogy courses. Yet, familiarity with mineral formulae facilitates the assimilation of many concepts dealing with mineral structures, coordination, and element substitutions, in addition to setting a context for geochemical problems encountered in other courses. Likewise, familiarity with a range of analytical techniques and equipment can open the door for valuable undergraduate research experiences, and lead to success in obtaining increasingly analytical entry-level jobs in geoscience-related fields. In-class discussion and flexible assessment schedules substantially improved retention of mineral formulae from one semester to the next, as opposed to other methods of “learning.” Students are given the opportunity to “take control of” their course grade by having the option of retaking mineral formulae quizzes, at the same time increasing short-term utility and long-term retention. In-class discussions and concept mapping of formulae were used to help students develop a context for the use and meaning of formulae. An inquiry-based approach to the learning of analytical techniques and equipment allows students to experiment with various aspects of the analysis of minerals. Precision and accuracy, sample preparation, pitfalls and shortcuts, in addition to the most efficient way of implementing the equipment are best discovered by trial-and-error. Students are assigned a piece of equipment or analytical method and must develop a Standard Operating Procedure (SOP) based on their understanding of the equipment. Presentation of their SOP facilitates discussion on similarities and differences, while introducing the entire class to a wide range of procedures.

Utility of a new soft non-woven polypropylene mesh for the transabdominal extraperitoneal laparoscopic hernia repair: preliminary results

Aims Tension-free mesh reinforcement is the mainstay of laparoscopic hernia repair. Problems with current prostheses include shrinkage, migration, patient discomfort and neuralgias. We prospectively analyzed the short-term utility of a soft, non-woven mesh (Biomesh W/NK®, Cousin Biotech) in the TAPP repair.

Bankruptcy and expected utility maximization

This paper introduces a utility formulation to the well-known gambler's ruin problem. An agent who maximizes lifetime expected utility has to trade off short-term utility against longer-term survival prospects. The optimal tradeoff is established by way of characterizing the agent's value and optimal policy functions. Further, the scope of expected utility maximization is examined by contrasting the bankruptcy probabilities of an agent employing such a criterion with those of an agent who is more directly interested in survival. Economic applications of the theory are also discussed.

Wearable air supply for pneumatic artificial hearts and ventricular assist devices.

An experimental wearable air supply for pneumatic artificial hearts and ventricular assist devices has been built and tested. The unit eliminates the need for tethering to a large, stationery driver. The miniaturized air supply is designed for ambulatory patients with implanted pulsatile pneumatic total artificial hearts (TAH) or pneumatic left-ventricular assist devices (LVAD), to permit mobility in clinical and home settings. The device has major short-term utility as a supply for pneumatic TAH or VAD bridges in patients awaiting heart transplants. The system design for the wearable driver includes a novel, fast rotary compressor, driven by a brushless direct current (DC) motor to supply air to the ventricle through an electromagnetically actuated directional valve, all controlled by a microcomputer. Stroke volume from 0 to 200 cc; pulse rate from 60 to 160 bpm, and duty cycle from 33% to 50% are selected on a keyboard, and the selected or measured parameters can be shown on a liquid crystal display. For control of delivery from a single ventricular assist device, stroke volume is controlled by variation of compressor speed. In the wearable air supply for a TAH, a single compressor drives both ventricles alternately through a double-acting directional valve. Air volume delivered to the left ventricle is adjusted by variation of compressor speed, and air volume to the right ventricle by variation of ejection time. The effect on blood flow rate of the lower impedance to the right ventricle is compensated by provision of a two-stage compressor, in which a single stage drives the right ventricle, and both stages connected in parallel drive the left ventricle. The overall dimensions of the prototype air supply for driving either a TAH or LVAD are 4.5 by 7.8 by 4.5 inches, including an emergency battery with a duration of 15 to 30 min depending on load. The weight is presently 5.5 lb, but this will be reduced in a production design and for a dedicated LVAD air supply. The size and weight of a separately worn, rechargeable battery pack depend on the load and desired duration of operation.

Inflammatory Bowel Disease

Inflammatory bowel disease encompasses both ulcerative colitis and Crohn's disease, two conditions so alike clinically that they are frequently indistinguishable from one another. Inflammatory bowel disease occurs at a rate of approximately five per 100,000 people. It tends to cluster in families and is seen four to five times more often in Jewish Caucasians than in other Caucasians. The etiology is unknown. Increasing attention is being paid to autoimmune factors, genetic factors and food allergies, and the notion that inflammatory bowel disease has its roots in a psychological disorder continues to pale for want of empirically sound evidence. Disease pattern is one of remission and exacerbation. The aim of therapy is to maintain an optimal lifestyle in remission through an individually tailored protocol of medications. Sulfasalazine remains the medication of choice; corticosteroids have short-term utility in exacerbation; and immunosuppressants, though controversial, are thought to have some steroid-sparing benefits during acute flare-ups. Indications for surgery vary, depending on whether or not a clear differential diagnosis has been made between ulcerative colitis and Crohn's disease. There is no cure for inflammatory bowel disease except for total colectomy in clearly diagnosed ulcerative colitis. Current research endeavors seek a cause or causes for inflammatory bowel disease, but the literature does not solidly support any one possibility above other rival etiologies.

Corralling the Free Rider: Deterrence and the Western Alliance

This paper uses the collective-goods approach to alliances to investigate how membership in the North Atlantic Treaty Organization and other American alliances affects the interaction between the United States and the other actors. The paper uses two models, differing in their assumptions about the factors involved in the calculations member states make, to derive hypotheses regarding the dynamics of intra-alliance behavior. I conclude that a “bargaining” model, which assumes that allies are concerned more with maintaining long-term mutual commitment than with maximizing short-term utility, better explains how allies act. The implications for the study of group behavior and the contributions to the understanding of alliances are discussed.

University research in flux: Policy debate in Australia

After a brief “golden age” Australian university research faces a difficult future. Two notions, utility and concentration, have become the catchwords of the emerging policy initiatives. Both have tended to be interpreted narrowly and simplistically, utility as having immediate technological applications that will bring economic benefits, and concentration to argue for breaking the teaching-research nexus, reducing the research workforce and thus achieving cost savings. As proposed, both initiatives require more centralised control of research policy and funding. Despite the outstanding record of Australia's universities in research and the absence of evidence to support the benefits claimed for the new initiatives, the pressure for change is gaining momentum. The problems facing Australian universities have much in common with those in other Western countries, although unique solutions must be sought for every setting. This paper argues that, in Australia, the adoption of the easy solution of increased concentration, short-term utility, and centralised control, is likely to compromise the established excellence and diversity in basic research, and to lead to an overall reduction in the scale of university research. Before any changes are instigated, there is a pressing need for a broad-ranging review based on widespread participation in a debate about needs and priorities, and rigorous research into the performance of the existing system and the potential benefits of the changes proposed.