Historic Operation Research Articles

Optimal Short-term Reservoir Operation with Integrated Long-term Goals

A methodology to incorporate long-term goals within the short-term reservoir operation optimization model is proposed. Two conflicting objectives for the management of hydropower generation in two different power plants are incorporated. A chance-constrained optimization model is used to derive long-term (annual) operation strategies. With the time horizon of operation for the short-term optimization model kept equal to a single time-step of the long-term optimization model, the optimum end storages derived from the long-term model are incorporated as constraints (storage lower bounds) within the short-term model. The long-term benefits accrued from such an operation model are illustrated for a small reservoir, in South India. The solutions are compared with the historic operation. These are also compared with the solutions of a short-term optimal operation model ignoring long-term goals. The optimization model is solved using a multi-objective genetic algorithm.

Mass spectrometric study of various coated targets utilizing the PUPR Mirror/Cusp plasma machine for the NASA Solar Probe space mission

The NASA Solar Probe space mission will be a historic operation, flying for the first time into one of the last unexplored regions of the solar system, the Sun's atmosphere or corona; hopefully revolutionizing our knowledge of the physics of the origin and evolution of the solar wind phenomenon. The spacecraft's most prominent feature is the thermal protection system (TPS), composed of a large carbon–carbon conical shield, designed to withstand the Sun's violent temperatures. Thermal testing will be conducted on various coatings on the carbon–carbon targets in order to study mass loss components using mass spectrometry. Mass spectrometry is an analytical technique used to measure the mass-to-charge ratio of ions. It is more generally used to find the composition of a physical sample by generating a mass spectrum representing the masses of sample components. By using a quadrupole mass spectrometer, the effects of plasma on various coated targets were analyzed and the effects of various gases on the plasma were studied on the PUPR Mirror/Cusp (M/C) plasma machine. A series of five tests was performed for this experiment; the first four tests consist of creating plasma with four different gases, and studying the effects of each gas on the plasma using mass spectrometry, in order to decide which plasma resembles the Sun's atmosphere or corona. The fifth test consists of introducing various coated targets, which represent the spacecraft's shield, inside the PUPR M/C plasma machine, to study how the different coatings react with the plasma that best bears a resemblance to the Sun's atmosphere, for approximately 12 h of exposure. After studying the results for the first four tests, it is evident that each gas has a distinctive effect on the plasma. For the fifth test following the study of the mass spectrometry results, it is clear that the quadrupole mass spectrometer was able to detect mass loss components for the introduced targets, and the presence of the coatings were successfully identified inside the PUPR M/C plasma machine, therefore assisting in the shield coating selection for the solar probe aircraft.

Impact of Irrigation Cessation on Wetland Communities within the Elk Ranch in Grand Teton National Park, Moose, Wyoming

This study began in 2006 to provide an ecologically based decision platform for Grand Teton National Park (GTNP) managers to use when evaluating the pros and cons of continuing the historic Elk Ranch irrigation operation. Ideally, this platform would also provide criteria for identifying landscapes within the irrigated hay meadows that would experience the most rapid change in vegetation community structure if the decision were to terminate irrigation operations. These criteria would aid in the identification of areas where species composition could quickly change as growing conditions shifted to the drier conditions common in surrounding undeveloped range and forestland. Once identified these sites could be closely managed to prevent invasive non-native species from disrupting site re-occupation by native upland species. To accomplish this goal the study was designed to 1) identify soil and hydrologic features associated with wetland and upland plant communities in the hayfield complex and 2) monitor shallow groundwater patterns associated with these wetland complexes. Predictive responses generated from the soil/vegetation inventories would then be compared with the recorded groundwater patterns to validate the measures as indicators of vegetation community change. If successful, these criteria will also be useful for identifying the potential for wetland mitigation and rehabilitation at other localities within Grand Teton National Park.

Japan’s first open-heart surgery with pump oxygenator

Fifty years have passed since Japan’s first open-heart surgery using a heart-lung apparatus on April 18, 1956 at Osaka University Hospital1—and, in the years since then, the number of open-heart surgeries conducted annually in this country has grown to some 50,000. p]The first patient was a 16-year-old boy with tetralogy of Fallot. Simpler cardiac anomalies such as atrial or ventricular septal defect had been operated upon using hypothermia with or without selective cerebral perfusion before this historic operation, so a tetralogy patient was selected as the first candidate for this procedure as more time was anticipated to be needed.

The first parathyroidectomy

Eighty years ago, on 30 July 1925, an historic operation in the evolution of endocrine surgery took place – the first parathyroidectomy for hyperparathyroidism.

Modelling of the extractive membrane bioreactor process based on natural fluorescence fingerprints and process operation history

A method for non-mechanistic and non-linear modelling of complex biological processes is presented, using the example of the extractive membrane bioreactor (EMB). The model is based on artificial neural networks (ANN), which are able to predict the state of the process from a combination of reactor operational parameters and natural fluorescence fingerprints. Current as well as historic process operation is included in the ANN input vector, in order to account for lag-times within the reactor system and for biofilm dynamics that are dependent on process history. The model is especially relevant for practitioners, as it does not require assumptions on underlying process mechanisms, and it relies on routinely available operational data and on an easy-to-install, non-invasive, in-situ, on-line monitoring method. Moreover, it focuses on the prediction of overall process performance parameters, which are of immediate relevance in practice. The developed model was able to predict the process state very well. Sensitivity analysis revealed that the main impact on process performance stems from process operation rather than the physiological state of the biological culture, and that in the EMB configuration employed process operation history decisively impacts on the process outcome.

Simulation-Based Dual Mode Controller for Nonlinear Processes

Abstract This paper presents a simulation-based strategy for designing anonlinear override control scheme to improve the performance of a local linear controller. The higher-level nonlinear controller monitors the dynamic state of the system under the local controller and sends an override control action whenever the system is predicted to move outside an acceptable operating regime under the local controller. For this purpose, a cost-to-go function is defined, an approximation of which is constructed hy using simulation or historic operation data. The cost-to-go function delineates the region of state space within which the local controller is effective, thereby yielding a switching rule. The same cost-to-go function can also be used to calculate override control actions designed to hring the system state back into the admissible region as quickly as possible. One potential problem of this approach is the lack of robustness when the simlllation data sparsely cover the state space and the data-based approximation of the cost-to-go function is extrapolated to a region previously unseen. Hence, successful application of the proposed method requires safeguarding against undue extrapolations. For this reason, a kernel-based local approximation, instead of a global approximator like a neural network, is used to interpolate the cost-to-go values. It is shown that the kernel-based local regression provides convenient means to implement a risk-sensitive control scheme which avoids excessive extrapolation. The proposed scheme is demonstrated and discussed with non linear examples.

Characterization of PAH Sources in Sediments of the Thea Foss/Wheeler Osgood Waterways, Tacoma, Washington

The character of polycyclic aromatic hydrocarbons (PAH) in sediments of the Thea Foss and Wheeler-Osgood Waterways in Tacoma, Washington, were investigated with the objective of determining the general source(s) of these compounds to the waterways. In this study, 42 near-surface sediment samples from the Waterways were collected and analyzed for their (1) concentration of 43 individual or groups of PAH, (2) total extractable hydrocarbon “fingerprint” and concentration, (3) grain size and (4) total organic carbon content. Analysis of the sediment data, including comparisons to standard reference materials, indicates that all but two samples contained PAH derived from a pyrogenic source(s), i.e., a non-petroleum source(s). The high concentrations and characteristic distributions of PAH in some sediment samples were consistent with the occurrence of manufactured gas plant (MGP) derived tar(s) or tar distillate(s), particularly in some sediments proximal to a historic MGP and tar distillate storage operation near the head of the Thea Foss Waterway. Most other sediment samples throughout the Waterways contained PAH distributions and concentration indicating (at least) a greater proportion of PAH are derived from urban runoff/fallout.

Cardiac Transplantation in Children

HISTORICAL OVERVIEW In 1967, Dr Christian Barnard1 captured the imagination of the world's lay and medical communities when he performed the first human orthotopic cardiac allotransplant. Although the recipient survived for only 17 days, even this limited success spurred many centers around the world to attempt heart transplantation in the late 1960s and early 1970s. Interestingly, Dr Adrian Kantrowitz2 in Brooklyn, NY, had attempted a human neonatal cardiac transplantation nearly coincidentally with Dr Barnard's historic operation; the neonate survived only a few hours. Because of poor results secondary to rejection, infection, and donor shortage, most centers had abandoned their heart transplantation programs by the middle 1970s. Experience at the few centers that persisted with heart transplantation, Stanford University being the most notable, led to improved candidate selection and improved immunosuppression. The introduction of endomyocardial biopsy in 19733 for the diagnosis of rejection also contributed substantially to improved understanding and management of this complication. In the late 1970s, encouraging results from Stanford prompted renewed interest in the procedure. However, pediatric experience, even at Stanford, was limited to a small number of adolescents during the 1970s. In 1980, the introduction of a new maintenance immunosuppressive drug, cyclosporine A, led to improved survival because of less infection and better management of the rejection process.

Cardiac transplantation in children.

HISTORICAL OVERVIEW In 1967, Dr Christian Barnard1 captured the imagination of the world9s lay and medical communities when he performed the first human orthotopic cardiac allotransplant. Although the recipient survived for only 17 days, even this limited success spurred many centers around the world to attempt heart transplantation in the late 1960s and early 1970s. Interestingly, Dr Adrian Kantrowitz2 in Brooklyn, NY, had attempted a human neonatal cardiac transplantation nearly coincidentally with Dr Barnard9s historic operation; the neonate survived only a few hours. Because of poor results secondary to rejection, infection, and donor shortage, most centers had abandoned their heart transplantation programs by the middle 1970s. Experience at the few centers that persisted with heart transplantation, Stanford University being the most notable, led to improved candidate selection and improved immunosuppression. The introduction of endomyocardial biopsy in 19733 for the diagnosis of rejection also contributed substantially to improved understanding and management of this complication. In the late 1970s, encouraging results from Stanford prompted renewed interest in the procedure. However, pediatric experience, even at Stanford, was limited to a small number of adolescents during the 1970s. In 1980, the introduction of a new maintenance immunosuppressive drug, cyclosporine A, led to improved survival because of less infection and better management of the rejection process.

20 years after first human heart transplant, 1987 may see 4000 procedures performed worldwide

THIS WEEK marks the 20th anniversary of the first human heart transplant (<i>JAMA</i>1967;202:23-24). Christiaan N. Barnard, MD, PhD, the surgeon who performed that transplant, recalled in a recent interview the events leading up to the historic operation. Cardiac transplantation to Barnard was merely a "new surgical technique." He began to think human heart transplants might be feasible when he read of a technique in 1959 in which the posterior walls of the recipient's atria were left behind. "Immediately, cardiac transplantation became a very straightforward surgical technique because it meant that you didn't have to anastomose the two vena cavae and the four pulmonary veins—all you had to anastomose were the two atria," he says. After studying for several months in the United States, Barnard, who is currently a scientist-in-residence at the Oklahoma Transplantation Institute, Baptist Medical Center, Oklahoma City, returned to South Africa ready to begin the patient-selection process.

20 Years After First Human Heart Transplant, 1987 May See 4000 Procedures Performed Worldwide

THIS WEEK marks the 20th anniversary of the first human heart transplant (<i>JAMA</i>1967;202:23-24). Christiaan N. Barnard, MD, PhD, the surgeon who performed that transplant, recalled in a recent interview the events leading up to the historic operation. Cardiac transplantation to Barnard was merely a "new surgical technique." He began to think human heart transplants might be feasible when he read of a technique in 1959 in which the posterior walls of the recipient's atria were left behind. "Immediately, cardiac transplantation became a very straightforward surgical technique because it meant that you didn't have to anastomose the two vena cavae and the four pulmonary veins—all you had to anastomose were the two atria," he says. After studying for several months in the United States, Barnard, who is currently a scientist-in-residence at the Oklahoma Transplantation Institute, Baptist Medical Center, Oklahoma City, returned to South Africa ready to begin the patient-selection process.

I'll Take Tomorrow: The Story of a Courageous Woman Who Dared to Subject Herself to a Medical Experiment—The First Successful Heart-Lung Transplant

ABSTRACT I'll Take Tomorrow is the fascinating autobiographical story of Mary Gohlke, the first long-term survivor of a heart-lung transplant. It is the chronicle of her discovery that she was dying of primary pulmonary hypertension and of the day-to-day events leading up to and following her historic operation. The author—wife, mother, and advertising executive— shares her physical, emotional, and mental struggle with the fantastic problems that are associated with successful cardiopulmonary transplantation, from organ rejection to behavioral disturbances and the need to readjust to family relationships and employment.Faced with the choice between certain death and another chance for life, Gohlke chose to subject herself to a dramatic experimental procedure. During her journey back to health, her optimism gave way at times to anxiety, despair, and even depression. Her moving account reminds us of just how taxing living with a transplanted organ can be. The book is filled with emotion and

Ephraim McDowell of Danville, Ky

To the Editor:— Your stamp filler ( 204 :766, 1968) concerned McDowell performing the historic operation in Danville, Va. Of course it was done in Danville, Ky, where he is something of a patron saint.