Unanticipated Variations Research Articles

OIL SPILL MONITORING USING SATELLITE IMAGERY IN THE SHARM EL-MAYA BAY OF SHARM EL-SHEIKH, EGYPT

Abstract. Sharm el-Sheikh, in Egypt, is a prominent tourist destination. The city attracts millions of visitors annually due to its exceptional location and pleasant climate. Owing to its natural ecosystem and marine diversity, Sharm El-Maya Bay in Sharm el-Sheikh attracts beachgoers and vacationers. In 1999, however, an oil spill occurred at the site. Previous investigations detected a network of buried steel pipelines and a number of buried reinforced concrete tanks, both of which may have contributed to the contamination problem. Although the problem is so detrimental to health and the environment, no follow-up studies were conducted after 2013. Therefore, the author chose to monitor oil leaks over the headland using frequent, high-resolution Google Earth Pro remote sensing data for the years 2017 to 2022. To disclose whether any corrective measures were taken to address the contamination problem. Moreover, to demonstrate if any unanticipated variations have occurred over many years due to climatic factors. The elucidation of the aforementioned issues demonstrates Google Earth Pro's effectiveness in monitoring pollution problems. The results revealed that the area and perimeter of four oil spots had changed slightly over time. During the specified time period, the standard deviations of the four monitored locations fluctuated between 111.1 m2, 71.6 m2, 83.7 m2, and 254.3 m2. The research proved that the pollution problem has not improved over time because stakeholders have not reacted. In addition, it highlighted the uniqueness of Google Earth Pro in tracking the changes in oil spot size over a time series.

A Practical Tool for Risk-Based In-use Compatibility Assessments

In drug development, in-use compatibility studies are crucial steps to ensure that the critical quality attributes of the drug product are maintained when in contact with administration components. But once the drug is in clinical trials, unanticipated variations in these components can stretch limited resources and lengthen timelines to market, as these changes must be assessed and approved to ensure continued patient safety. It's desirable to use a science-based risk evaluation to determine the extent of data and testing needed in these situations, but there is no standard for how such evaluations are done. We have developed an Excel™-based semi-quantitative risk assessment tool to determine whether in-use testing is needed when drug delivery sites or components are changed during a clinical trial. We developed the tool based on our multi-company experience with compatibility studies for many types of drug products targeted for various geographic regions. We have employed the tool as a means to expedite decision-making and, if appropriate, reduce testing in low-risk situations. The tool can save significant time and effort (our estimate is approximately at least 6-9 months off the development cycle) and can minimize pitfalls in clinical administration. While we have designed the tool for our drug products and for use with parenteral dosing regimens, the tool can be adapted for other situations as needed. It will be especially useful for companies with more limited resources.

A big data approach to cargo type prediction and its implications for oil trade estimation

To estimate global crude oil trade flows, current research either considers only crude oil tankers, or simply applies external information to distinguish between crude and refined product oil cargoes transported by coated product tankers; these limitations often reduce an estimation’s accuracy or compromise replicability. Our methodology directly addresses these issues by applying the random forest (RF) ensemble learning technique to Automatic Identification System (AIS) data in order to predict the cargo types of coated product tankers. By leveraging domain knowledge, we construct a set of unique input variables for the RF model, and use its predictions to quantify the global crude oil trade in a more accurate manner. Our estimation shows that coated product tankers were responsible for approximately 8% of global seaborne crude oil trade from 2017–2020. Further, unanticipated variations in the crude oil volume carried by these tankers are consistent with several major historical oil trade disruptions. Our study further extends current applications of AIS data in the domains of operations management and maritime transportation, and facilitates the exploration of the more minute characteristics of oil transportation. The resulting shipping dataset and associated decomposition strategy also enable relevant stakeholders to quickly identify emerging trade flow risks and adapt more effectively.

Stepping onto the unknown: reflexes of the foot and ankle while stepping with perturbed perceptions of terrain.

Unanticipated variations in terrain can destabilize the body. The foot is the primary interface with the ground and we know that cutaneous reflexes provide important sensory feedback. However, little is known about the contribution of stretch reflexes from the muscles within the foot to upright stability. We used intramuscular electromyography measurements of the foot muscles flexor digitorum brevis (FDB) and abductor hallucis (AH) to show for the first time how their short-latency stretch reflex response (SLR) may play an important role in responding to stepping perturbations. The SLR of FDB and AH was highest for downwards steps and lowest for upwards steps, with the response amplitude for level and compliant steps in between. When the type of terrain was unknown or unexpected to the participant, the SLR of AH and the ankle muscle soleus tended to decrease. We found significant relationships between the contact kinematics and forces of the leg and the SLR, but a person's expectation still had significant effects even after accounting for these relationships. Motor control models of short-latency body stabilization should not only include local muscle dynamics, but also predictions of terrain based on higher level information such as from vision or memory.

Source-Side Virtual RC Damper-Based Stabilization Technique for Cascaded Systems in DC Microgrids

Cascaded connection of power converters is a dominant connection form in DC microgrids. In such systems, despite the possible instability caused by the impedance interactions between the individually designed converters, tightly regulated load converters acting as constant power loads (CPLs) tend to destabilize the system owing to their negative resistance characteristics. Hence, this paper proposes a new virtual series RC damper in parallel with the source-side converter's capacitor without compromising the load's dynamic performance. Using this design-oriented active damping method, which utilizes a simple control structure with a more straightforward tuning of the control parameter, the stability and performance of the system are guaranteed. The feasibility and robustness of the suggested active stabilization idea against unanticipated variations in input voltage amplitude, and CPL power rating (load changes) as well as step changes in output voltage reference, are also authenticated. The control and operation principles, as well as the circuit physical meaning realized by the presented technique for three cascaded systems comprising the basic DC/DC converters feeding CPLs, are theoretically analyzed. Simulation and experimental results are provided to validate the effectiveness of the proposed active stabilizer.

Hybrid Robotic Reinforcement Learning for Inspection/Correction Tasks

The ability to rapidly program robots for complex tasks is an important precursor to wider adoption of robotics in industry. Robot programming is often time consuming and brittle to unanticipated variations in processing. Automated robot task learning is a solution to this problem. Reinforcement Learning (RL) is a commonly used approach for a robot to autonomously learn simple tasks. In RL, rewards are used to guide the robot towards learning an optimal plan or control policy. RL, however, has proven to be of limited value for problems with large-state spaces and considerable environmental variability. In this paper, we investigate formulation of the RL approach for inspect/correct types of tasks, specifically a misplaced block in a simple grid-world environment (requiring searching the gird world to identify a missing block and returning the missing block back to the target). We use a hybrid method, combining the SARSA algorithm and a model of the environment. The model of the environment is used as a reference model to reduce the state space, avoiding unnecessary exploration of the environment. A main focus of this research is the impact of task variability on RL performance.

Postirradiation examination on metallic fuel in the AFC-2 irradiation test series

Irradiation experiments on metallic fuel alloys containing rare earth additions to simulate potential carry-over from pyro-metallurgical reprocessing and minor actinide additions were performed in the Idaho National Laboratory Advanced Test Reactor. These tests were designated AFC-2A and AFC-2B. Additionally irradiation experiments were also performed on metallic fuel alloys containing minor actinide additions that were fabricated by different techniques. These tests were designated AFC-2E. These pins were removed from the reactor after achieving burnups between 6 and 11% fission per initial heave metal atom. Examination of these pins revealed that they were unintentionally operated beyond their desired power and temperature conditions. Highlights from the postirradiation examination of these experiments is discussed. A variety of issue contributed to the poor performance of these irradiation tests including capsule design, reactor power variations and fabrication issues. While all the issues contributed, the major issue was determined to be unanticipated variations in reactor power. Through comparisons between these experiments and historical off-normal experiments, it was possible to conclude bound the operating temperatures of these experiments. There likely was some in-pile melting in the rare earth addition experiments (AFC-2A, AFC-2B), but it is not likely that there was in-pile melting in the fabrication technique experiments (AFC-2E).

Stock Market Reaction to Monetary Policy: An Event Study Analysis of the Brazilian Case

ABSTRACTThis article examines the relationship between the monetary policy implemented by the Central Bank of Brazil and the stock market. We implement event study analysis and analyze the effect of the anticipated and unanticipated components of monetary policy decisions on the returns of the IBOVESPA index and 53 stocks. We find that monetary policy has a significant effect on the stock market, but is only responsible for a small proportion of market variation. The analysis at the sector level with expected returns identifies that the financial sector is the most affected by this policy, whereas with excess returns only industrial goods are significantly affected. Moreover, individual assets respond in a rather heterogeneous fashion to monetary policy; however, when we look at excess returns, we identify a reduction in the intensity and in the number of companies impacted by monetary policy. Finally, the monetary shock is explained by unanticipated variations in the unemployment rate, in the Industrial Production Index, in the General Market Price Index, and in the Broad Consumer Price Index.

Advancement and economic benefit of geosteering and well-placement technology

In the development of many of today's reservoirs, the oil and gas industry is challenged to drill more efficiently and is asked constantly to maximize recovery and production. However, drilling through these reservoirs is challenging because geologic models often are limited to the resolution of seismic data, and offset wells often have significant variations. Geosteering is the process of adjusting the borehole trajectory in real time to correct for unanticipated variations in geology and structure to avoid exiting the target zone. It is a technique currently used on many horizontal and deviated wells for better well placement and for efficiently draining a reservoir. Recent improvements in well-placement and formation-evaluation technologies have helped in gaining access to bypassed reserves that originally were not thought to be practical targets. Examples highlight the economic benefit of geosteering and well-placement technology. Maximum reservoir contact in the sweet spot leads to increased production, and early warning of approaching faults and bed boundaries results in reduction of sidetracks. Furthermore, keeping the well trajectory away from the oil-water contact optimizes production by producing less water. Finally, maximizing production by placing the wellbore entirely within the best reservoir zone boosts productivity so that wells that previously appeared difficult or uneconomic are now becoming viable.

Rinderpest: the veterinary perspective on eradication.

Rinderpest was a devastating disease of livestock responsible for continent-wide famine and poverty. Centuries of veterinary advances culminated in 2011 with the UN Food and Agriculture Organization and the World Organization for Animal Health declaring global eradication of rinderpest; only the second disease to be eradicated and the greatest veterinary achievement of our time. Conventional control measures, principally mass vaccination combined with zoosanitary procedures, led to substantial declines in the incidence of rinderpest. However, during the past decades, innovative strategies were deployed for the last mile to overcome diagnostic and surveillance challenges, unanticipated variations in virus pathogenicity, circulation of disease in wildlife populations and to service remote and nomadic communities in often-unstable states. This review provides an overview of these challenges, describes how they were overcome and identifies key factors for this success.

Global strategy formulation and learning from the field: Three modes of comparative learning and a case illustration

AbstractFirms formulate their global strategies from what they have learned from observing others and from their own experiences relying on the logic of comparison. From the literature and an in‐depth case analysis, we identify three modes of comparative learning for global strategy formulation: seeking best practice, surfacing universals, and grounded strategizing. We argue that grounded strategizing, which we define as the process by which firms learn from unanticipated variations in their own global strategy implementation, is often inferred, remains relatively unexplored, and may provide the most valuable source of learning. By examining the case of NSK Ball Bearings, we show that strategy formulation is much like theory building—each era of internationalization has its own theoretical foundation based on differing basic assumptions and logics of comparison.

Can we settle with single-band radiometric temperature monitoring during hyperthermia treatment of chestwall recurrence of breast cancer using a dual-mode transceiving applicator?

The total thermal dose that can be delivered during hyperthermia treatments is frequently limited by temperature heterogeneities in the heated tissue volume. Reliable temperature information on the heated area is thus vital for the optimization of clinical dosimetry. Microwave radiometry has been proposed as an accurate, quick and painless temperature sensing technique for biological tissue. Advantages include the ability to sense volume-averaged temperatures from subsurface tissue non-invasively, rather than with a limited set of point measurements typical of implanted temperature probes. We present a procedure to estimate the maximum tissue temperature from a single radiometric brightness temperature which is based on a numerical simulation of 3D tissue temperature distributions induced by microwave heating at 915 MHz. The temperature retrieval scheme is evaluated against errors arising from unknown variations in thermal, electromagnetic and design model parameters. Whereas realistic deviations from base values of dielectric and thermal parameters have only marginal impact on performance, pronounced deviations in estimated maximum tissue temperature are observed for unanticipated variations of the temperature or thickness of the bolus compartment. The need to pay particular attention to these latter applicator construction parameters in future clinical implementation of the thermometric method is emphasized.

Comparison of CINAHL® via EBSCOhost®, Ovid®, and ProQuest®

CINAHL® database characteristics were examined in three vendor products. A number of unanticipated variations concerning category terms, field tags and their definitions, and search results are noted and discussed. Interface highlights are also explored. Knowing the characteristics of the vendor interface being used allows the searcher to accommodate unique variations when helpful or necessary. Usefulness of interface characteristics and features, display settings, and content are framed by the user's experiences, needs, and preferences. This investigation will be of assistance to those who wish to compare characteristics of three major CINAHL versions, and will be of interest and value to any CINAHL user.

Markups, Aggregation, and Inventory Adjustment

In this paper I suggest a unified explanation for two puzzles in the inventory literature: first, estimates of inventory speeds of adjustment in aggregate data are very small relative to the apparent rapid reaction of stocks to unanticipated variations in sales. Second, estimates of inventory speeds of adjustment in firm-level data are significantly higher than in aggregate data. The paper develops a multi-sector model where inventories are held to avoid stockouts, and price markups vary along the business cycle. The omission of countercyclical markup variations from inventory targets introduces a downward bias in estimates of adjustment speeds obtained from partial adjustment models. When the cyclicality of markups differs across sectors, this downward bias is shown to be more severe with aggregate rather than firm-level data. Similar results apply not only to inventories, but also to labor and prices. Montercarlo simulations of a calibrated version of the model suggest that these biases are quantitatively significant.

Unanticipated variations between expected and delivered pneumatic compression therapy after elective hip surgery: A possible source of variation in reported patient outcomes

The differences between the pneumatic compression thromboprophylaxis delivered after elective total hip arthroplasties and that was expected were quantified before (49 patients) and after a concerted nursing education program (30 patients) that was designed to ensure maximum compliance and to verify the correct application of the devices. The expected therapy was not delivered to any of the patients monitored. Therapy was delivered only an average of 77.8% of the time during the expected treatment periods. During 99.9% of the expected therapy times, values of key outcomes-related parameters of the therapy delivered to the patients varied by >10% from expected values. These variations were not reduced significantly by medical and nursing education. This variation may be a significant confounding factor in comparatively evaluating thromboembolic disease outcome reports.

Interpretive Pitfalls in Historical Hazards Data

The primary use of the natural hazards data archived at the National Geophysical Data Center (NGDC) and co-located World Data Center for Solid Earth Geophysics (WDC for SEG) is for the mitigation of future disasters. Among the responsibilities of NGDC/WDC for SEG is archiving and disseminating hazards data to city planners, educators, engineers and others engaged in mitigation efforts (approximately 150,000 users per week on our web site). Therefore, it is the purpose of this paper to educate the hazards' community about some of the limitations of these data. It is hoped that enlightened users would have a greater appreciation of data errors and possible sources of misinterpretation of the data. Personnel at NGDC/WDC for SEG are in a unique position to discuss the limitations of hazards data since we compile data from original and secondary sources. We are also in direct contact with the data users and know the applications that they make of hazard data, and the misjudgments that often occur when data limitations are not known. Most hazard catalogs cover periods of less than 200 years and are reasonably complete and accurate for only the past 20 to 50 years. Such catalogs are not sufficient to investigate long term hazard variations. Earthquake, tsunami, and volcano data catalogs, acquired and integrated at NGDC/WDC for SEG, illustrate artificial long-term variations created by cultural and scientific reporting changes, which can introduce unanticipated non-random variations into the catalogs. Inconsistencies are often related to changes in the way magnitudes are calculated, evolving network equipment, and network discontinuities of operation and personnel, among other error sources. Before statistical hazard studies can be done, catalogs need to be clearly understood to identify systematic patterns of an observational nature.

The new biology enters the generalist pediatrician's office: lessons from the Human Genome Project.

1. Edward R.B. McCabe, MD, PhD* 1. 2. *Physician-in-Chief, Mattel Children’s Hospital at UCLA; Professor and Executive Chair, Department of Pediatrics, UCLA School of Medicine, Los Angeles, CA. Birth defects are the leading cause of infant mortality in the United States, representing more than 20% of all infant deaths. This infant mortality rate from birth defects exceeds that from sudden infant death syndrome, low-birthweight/short gestation, respiratory distress syndrome, and maternal complications. In addition, birth defects and genetic diseases represent major sources of morbidity for those who survive. As our ability increases to care effectively for those who have infectious diseases and other acute illnesses, individuals who have chronic illnesses due to genetic etiologies represent an increasing proportion of patients seen in the general pediatrician”s office. The Human Genome Project was initiated on October 1, 1990, and has a projected funding period of 15 years. The goal is to sequence the entire human genome, representing three billion base pairs that contain the coding sequences for approximately 75,000 genes. During the latter half of this century, investigations into the genetics of disease gathered increasing momentum. In addition to fundamental investigations into human genetics, technologic tools were developed that permitted large-scale genomic sequencing. These tools included the polymerase chain reaction (PCR), which permits amplification of hundreds of thousands or even millions of copies of DNA and requires only limited sequence data for its success; automated DNA sequencing, which allows increased sequence processing and decreased cost compared with manual methods; and improved information systems, which permit sophisticated analysis and assembly of the three billion base pairs of DNA in the human genome. Thus, the Human Genome Project represents the current chapter in our understanding, but it is neither the first nor the final chapter in this story. Once we know the sequences of all of the human genes, we must learn their functional roles in human development and disease pathogenesis. The Human Genome Project has been referred to as the “moon shot …

Integrated Reservoir Characterization of a Heterogeneous Channel Sandstone: The Duchess Lower Mannville X Pool

Abstract The Basal Quartz sandstone in the Duchess field of southern Alberta exhibits notable reservoir heterogeneity at various scales due to complex lithostratigraphy and overprinting by early diagenetic soil-related processes. Proper reservoir delineation, reserves assessment and simulation modelling has required the integration of stratigraphy, sedimentology, petrology, petrophysics, drill cuttings analysis and reservoir engineering. The main reservoir in Duchess consists of a two-tiered layercake of variably permeable fluvial sandstone approximately 25 m thick filling an incised valley roughly 800 m wide. After integrating all pertinent information, a reservoir simulation was done to provide performance predictions for the pool under different development scenarios. Twenty performance predictions were run. Results showed that conversion of selected wells to injection and horizontal infill wells should increase the recovery from 6.7% to 13.7% of the OOIP. However, due to the geological heterogeneity, the extensive gas cap, and a high in situ oil viscosity the Duchess pool was not the best candidate to waterflood. Introduction The Duchess Lower Mannville X pool is located in Township 21, Range 14 and 15 West of the Fourth Meridian (Figure 1). The pool was discovered in 1994 with the drilling of the well 08-12- 21-14w4m which tested oil out of the Basal Quartz formation at a depth of 1,092 m KB. Based on the gamma ray log signature in the discovery well, combined with a regional understanding of the depositional setting, it was inferred that the Basal Quartz reservoir consisted of stacked fluvial channel sandstones. To date this pool has produced a total of 42.0 ??103m3 of oil, 22 ??106 m3 of gas, and 14 ??103 m3 of water. Subsequent drilling encountered stacked hydrocarbon-bearing Basal Quartz channel sandstones of similar thickness. However, in many instances, the Basal Quartz reservoir sandstones exhibit large unanticipated intrawell and interwell variations in log derived porosity and resistivity. For instance, in some wells, sandstones in the upper portion of the reservoir are highly porous and hydrocarbon bearing, whereas in adjacent wells, the same sandstone interval has little porosity, sub-economic hydrocarbon saturation and anomalously well developed porosity at the base of the reservoir unit (Figure 2). An extensive gas cap was encountered in most of the wells. Despite the thick oil zone (as much as 15 m) and completing the wells as far from the gas as possible, most wells were producing with a high GOR. Cement squeezes were attempted but generally did not work or did so only temporarily. Production was low because the wells were penalized from the high GORs. In view of the complexity of the reservoir, a detailed evaluation of the reservoir was initiated, with the aim of developing a plan to optimize the economic recovery from the pool and gain a better understanding of this reservoir type for future Basal Quartz plays. The evaluation was multi-disciplinary, and included the following:Core examinationRoutine and advanced core analysisThin section petrographic analysisPetrophysicsDrill cuttings analysisGeological mappingReservoir simulationEconomics

Real government size, automatic feedback rules and the measured effectiveness of fiscal policy

This paper argues that as intervention, fiscal policy means more than simply any change in government spending and this requires of fiscal analysis a measure that separates the allocative from the counter-cyclical activities of government. Defining intervention as an optimal policy rule that responds automatically to privately unanticipated variations in output, a general equilibrium model is built to separate the supply side effects of desired changes in the size of government from demand side interventions designed to stimulate aggregate demand. The model is tested using the results of a public choice investigation of the real size of government (Ferris and West, 1996). That exercise produces a measure of desired size and, through its residual, an implicit measure of intervention. The paper tests the prediction that increases in desired size increase aggregate supply and that ex post measures of fiscal intervention can be recovered and tested for their effect on aggregate output. The test uses CITIBASE US annual data from 1959 through 1989.

Accounting for supply, integration and income in foreign trade

This paper provides alternative estimates of export and import demand functions. It is suggested that previous estimates of export and import functions may be biased since they ignore factors such as the integration of markets through customs unions and supply effects. The results in this paper reveal that when these factors are incorporated into the model, the estimated income elasticities of exports and imports decline substantially and trade flows are found to be more responsive to unanticipated variations in income. The analysis further reveals that the degree of integration in markets is closely linked to the level of economic growth.