Unified Assessment of Unconventional Resource Plays – Implications for Global Exploration and Development

2021 ◽  
Author(s):  
Tarun Grover ◽  
Jamie Stuart Andrews ◽  
Irfan Ahmed ◽  
Ibnu Hafidz Arief
Keyword(s):  
Commodity Prices ◽  
Design Parameters ◽  
First Year ◽  
Well Productivity ◽  
Well Spacing ◽  
Cumulative Production ◽  
Unconventional Resource ◽  
Log Normal ◽  
The Impact ◽  
Sweet Spots

Abstract Unconventional resource plays, herein referred to as source rock plays, have been able to significantly increase the supply of hydrocarbons to the world. However, majority of the companies developing these resource plays have struggled to generate consistent positive cash flows, even during periods of stable commodity prices and after successfully reducing the development costs. The fundamental reasons for poor financial performance can be attributed to various reasons, such as; rush to lease acreage and drill wells to hold acreage, delayed mapping of sweet spots, slow acknowledgement of high geological variability, spending significant capital in trial and errors to narrow down optimal combinations of well spacing and stimulation designs. The objective of this paper is to present a systematic integrated multidisciplinary analysis of several unconventional plays worldwide which, if used consistently, can lead to significantly improved economics. We present an analysis of several unconventional plays in the US and Argentina with fluid systems ranging from dry gas to black oil. We utilize the publicly available datasets of well stimulation and production data along with laboratory measured core data to evaluate the sweet spots, the measure of well productivity, and the variability in well productivity. We investigate the design parameters which show the strongest correlation to well productivity. This step allows us to normalize the well productivity in such a way that the underlying well productivity variability due to geology is extracted. We can thus identify the number of wells which should be drilled to establish geology driven productivity variability. Finally, we investigate the impact of well spacing on well productivity. The data indicates that, for any well, first year cumulative production is a robust measure of ultimate well productivity. The injected slurry volume shows the best correlation to the well productivity and "completion normalized" well productivity can be defined as first year cumulative production per barrel of injected slurry volume. However, if well spacing is smaller than the created hydraulic fracture network, the potential gain of well productivity is negated leading to poor economics. Normalized well productivity is log-normally distributed in any play due to log-normal distribution of permeability and the sweet spots will generally be defined by most permeable portions of the play. Normalized well productivity is shown to be independent of areal scale of any play. We show that in every play analyzed, typically 20-50 wells (with successful stimulation and production) are sufficient to extract the log-normal productivity distribution depending on play size and target intervals. We demonstrate that once the log-normal behavior is anticipated, creation of production profiles with p10-p50-p90 values is quite straightforward. The way the data analysis is presented can be easily replicated and utilized by any operator worldwide which can be useful in evaluation of unconventional resource play opportunities.

The role of reservoir modelling in unlocking unconventional (resource) plays

2013 ◽  
Vol 53 (2) ◽  
pp. 440
Author(s):  
Hiwa Sidiq ◽  
Eli Silalahi ◽  
Grant Skinner ◽  
Perdana Noverda Pamurty
Keyword(s):  
Seismic Data ◽  
Fracture Network ◽  
Fracture Density ◽  
Reservoir Modelling ◽  
Technical Developments ◽  
Well Spacing ◽  
Shale Reservoirs ◽  
Unconventional Resource ◽  
Sweet Spots

There has been a recent focus on the insight that reservoir modelling provides into devising the best workflows and its ability to include reservoir attributes that affect recovery factors in shale. This extended abstract examines recent technical developments in reservoir modelling and how such modelling can identify sweet spots in shale reservoirs. An accurate characterisation of a pre-existing fracture network and its structural complexities, however, requires the gathering of a large amount of data. In addition, investigating sweet spots at the presently low gas prices sometimes prevents the acquisition of such data that is essential as an input to drilling strategies, fracture program design, well spacing, and understanding stimulated reservoir volumes (SRV) in shale. The pre-existing fractures may also have a limited impact on recovery rates. The transport along a wellbore is mainly controlled by the drained volume, not only by the fractures around the well. In such cases, the pre-existing fractures and their reactivation during the fracturing stage are not sufficient to determine the amount of gas that can be recovered during production. This volume is effectively not only a function of the fracture density, but also of the propped fractures. The challenge, therefore, becomes the ability to have a good estimation of the size of the SRV and be able to calibrate this volume using relevant data such as micro-seismic data and the recovery from previous fraccing stages. This extended abstract also discusses how reservoir modelling can play a key role in this area.

The Need to Belong and the Relationship Between Loneliness and Health

2014 ◽  
Vol 22 (4) ◽  
pp. 194-201 ◽  
Author(s):  
Freda-Marie Hartung ◽  
Britta Renner
Keyword(s):  
Individual Differences ◽  
Social Isolation ◽  
Social Situation ◽  
First Year ◽  
Health State ◽  
Need To Belong ◽  
First Year University ◽  
Perceived Social Isolation ◽  
The Impact ◽  
The Relationship

Humans are social animals; consequently, a lack of social ties affects individuals’ health negatively. However, the desire to belong differs between individuals, raising the question of whether individual differences in the need to belong moderate the impact of perceived social isolation on health. In the present study, 77 first-year university students rated their loneliness and health every 6 weeks for 18 weeks. Individual differences in the need to belong were found to moderate the relationship between loneliness and current health state. Specifically, lonely students with a high need to belong reported more days of illness than those with a low need to belong. In contrast, the strength of the need to belong had no effect on students who did not feel lonely. Thus, people who have a strong need to belong appear to suffer from loneliness and become ill more often, whereas people with a weak need to belong appear to stand loneliness better and are comparatively healthy. The study implies that social isolation does not impact all individuals identically; instead, the fit between the social situation and an individual’s need appears to be crucial for an individual’s functioning.

Global Food Commodity Prices and Domestic Food Inflation: Some Insights from Morocco

New Medit ◽  
2020 ◽  
Vol 19 (3) ◽  
Author(s):  
Ahmed EL GHIN ◽  
Mounir EL-KARIMI
Keyword(s):  
Exchange Rate Regime ◽  
Commodity Prices ◽  
Food Prices ◽  
Consumer Prices ◽  
Floating Exchange Rate ◽  
Pass Through ◽  
The Impact ◽  
Food Inflation ◽  
Global Food ◽  
Domestic Food

This paper examines the world commodity prices pass-through to food inflation in Morocco, over the period 2004-2018, by using Structural Vector Autoregression (SVAR) model on monthly data. Several interesting results are found from this study. First, the impact of global food prices on domestic food inflation is shown significant, which reflects the large imported component in the domestic food consumption basket. Second, the transmission effect is found to vary across commodities. Consumer prices of cereals and oils significantly and positively respond to external price shocks, while those of dairy and beverages are weakly influenced. Third, there is evidence of asymmetries in the pass-through from world to domestic food prices, where external positive shocks generate a stronger local prices response than negative ones. This situation is indicative of policy and market distortions, namely the subsidies, price controls, and weak competitive market structures. Our findings suggest that food price movements should require much attention in monetary policymaking, especially that the country has taken preliminary steps towards the adoption of floating exchange rate regime.

INFLUENCE OF THE DIFFERENT SOIL PREPARATION METHODS ON THE PEA YIELD

2018 ◽  
pp. 16-20
Author(s):  
А. М. Grebennikov ◽  
А. S. Frid ◽  
V. P. Belobrov ◽  
V. А. Isaev ◽  
V. М. Garmashоv ◽  
...  
Keyword(s):  
Field Experiments ◽  
Morphological Properties ◽  
Mineral Fertilizers ◽  
First Year ◽  
Zero Tillage ◽  
Preparation Methods ◽  
Soil Preparation ◽  
Multifactor Analysis ◽  
The Impact ◽  
Central Chernozem

The article assesses the relationships between the morphological properties of agrochernozems and yield of peas on the plots, experience with different methods of basic treatment (moldboard plowing at the depth of 20 - 22, 25 - 27 and 14 - 16 cm, moldboard plowing to a depth of 14 - 16 cm, combined midwater moldboard, mid-water subsurface, surface to a depth of 6 - 8 cm and zero tillage) is inherent in V.V. Dokuchaev Research Institute of Agriculture of the Central Black Earth strip, in the fall of 2014. The research was conducted in 2015 - 2016, with the application of mineral fertilizers (N60Р60К60) and unfertilized background. The highest pea yields in the fertilized as the background, and without the use of fertilizers was observed in dumping plowing and especially in the variant with deep moldboard plowing, which creates in comparison with other ways of handling the best conditions for the growth and development of peas. The lowest yield of pea was obtained with zero processing. Apparently legalistic migrational-mizelial agrochernozems the Central Chernozem zone of minimum tillage in the cultivation of peas are not effective, what is evident already in the first year after the laying of experience with different basic treatments. As shown by the results of applying multifactor analysis of variance studied the mapping properties of the soil can have the same significant impact on the yield of agricultural crops, as options for the field experiments aimed at assessing the impact of various treatments on yield.

scholarly journals Bridging the gap: blending spatial skills instruction into a technology teacher preparation programme

2021 ◽  
Author(s):  
Diarmaid Lane ◽  
Sheryl Sorby
Keyword(s):  
Teacher Preparation ◽  
Gender Gap ◽  
Future Research ◽  
First Year ◽  
Spatial Skills ◽  
First Year Students ◽  
Base Level ◽  
Technology Teacher ◽  
And Mathematics ◽  
The Impact

AbstractIn recent years, there has been a surge in research in spatial thinking across the international community. We now know that spatial skills are malleable and that they are linked to success across multiple disciplines, most notably Science, Technology, Engineering and Mathematics (STEM). While spatial skills have been examined by cognitive scientists in laboratory environments for decades, current research is examining how these skills can be developed in field-based environments. In this paper, we present findings from a study within a Technology Teacher preparation programme where we examined first-year students’ spatial skills on entry to university. We explain why it was necessary to embed a spatial skills intervention into Year 1 of the programme and we describe the impact that this had on students’ spatial scores and on academic performance. The findings from our study highlight a consistent gender gap in spatial scores at the start of the first-year with female students entering the Technology Teacher preparation programme at a lower base level than male students. We describe how we integrated spatial development activities into an existing course and how an improvement in spatial scores and overall course performance was observed. The paper concludes by discussing the long-term sustainability of integrating spatial interventions within teacher preparation programmes while also highlighting the importance of future research to examine spatial skills as a fundamental component of technological capability.

scholarly journals Socio-economic consequences of mental distress: quantifying the impact of self-reported mental distress on the days of incapacity to work and medical costs in a two-year period: a longitudinal study in Germany

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Gerhard Müller ◽  
Manuela Bombana ◽  
Monika Heinzel-Gutenbrenner ◽  
Nikolaus Kleindienst ◽  
Martin Bohus ◽  
...  
Keyword(s):  
Mental Disorders ◽  
Mental Distress ◽  
Linear Models ◽  
Longitudinal Research ◽  
Depression Scale ◽  
Routine Data ◽  
Medical Costs ◽  
First Year ◽  
Second Year ◽  
The Impact

Abstract Background Mental disorders are related to high individual suffering and significant socio-economic burdens. However, it remains unclear to what extent self-reported mental distress is related to individuals’ days of incapacity to work and their medical costs. This study aims to investigate the impact of self-reported mental distress for specific and non-specific days of incapacity to work and specific and non-specific medical costs over a two-year span. Method Within a longitudinal research design, 2287 study participants’ mental distress was assessed using the Hospital Anxiety and Depression Scale (HADS). HADS scores were included as predictors in generalized linear models with a Tweedie distribution with log link function to predict participants’ days of incapacity to work and medical costs retrieved from their health insurance routine data during the following two-year period. Results Current mental distress was found to be significantly related to the number of specific days absent from work and medical costs. Compared to participants classified as no cases by the HADS (2.6 days), severe case participants showed 27.3-times as many specific days of incapacity to work in the first year (72 days) and 10.3-times as many days in the second year (44 days), and resulted in 11.4-times more medical costs in the first year (2272 EUR) and 6.2-times more in the second year (1319 EUR). The relationship of mental distress to non-specific days of incapacity to work and non-specific medical costs was also significant, but mainly driven from specific absent days and specific medical costs. Our results also indicate that the prevalence of presenteeism is considerably high: 42% of individuals continued to go to work despite severe mental distress. Conclusions Our results show that self-reported mental distress, assessed by the HADS, is highly related to the days of incapacity to work and medical costs in the two-year period. Reducing mental distress by improving preventive structures for at-risk populations and increasing access to evidence-based treatments for individuals with mental disorders might, therefore, pay for itself and could help to reduce public costs.

scholarly journals Positive and Negative Affect Changes during Gender-Affirming Hormonal Treatment: Results from the European Network for the Investigation of Gender Incongruence (ENIGI)

2021 ◽  
Vol 10 (2) ◽  
pp. 296
Author(s):  
Imke Matthys ◽  
Justine Defreyne ◽  
Els Elaut ◽  
Alessandra Daphne Fisher ◽  
Baudewijntje P. C. Kreukels ◽  
...  
Keyword(s):  
Negative Affect ◽  
Sex Steroids ◽  
Hormonal Treatment ◽  
Control Group ◽  
First Year ◽  
Positive And Negative Affect ◽  
European Network ◽  
Psychological Burden ◽  
The Impact

Improving transgender people’s quality of life (QoL) is the most important goal of gender-affirming care. Prospective changes in affect can influence QoL. We aim to assess the impact of initiating gender-affirming hormonal treatment (HT) on affect. In the European Network for the Investigation of Gender Incongruence (ENIGI) study, we prospectively collected data of 873 participants (451 transwomen (TW) and 422 transmen (TM)). At baseline, psychological questionnaires including the Positive and Negative Affect Schedule (PANAS) were administered. The PANAS, levels of sex steroids and physical changes were registered at each follow-up visit during a 3-year follow-up period, starting at the initiation of hormonal therapy. Data were analyzed cross-sectionally and prospectively. Over the first three months, we observed a decline in positive affect (PA) in both TM and TW. Thereafter, PA reached a steady state in TW, whereas in TM there was also a second decline at 18 months. In both TM and TW there was no persisting difference comparing baseline to the 36-months results. Concerning negative affect (NA), we observed a decline during the first year in TM, which sustained during the second year and was not different anymore at 36 months compared to baseline. In TW though, we did not find any change of NA during the entire follow-up. Even if some of these results show significant differences, they should be considered with caution, since there was no control group and the absolute differences are small. No association between affect and the level of sex steroids was observed. Baseline QoL and psychological burden are related to affect independently from gender but are not necessarily good predictors of the evolution of one’s affect during the gender-affirming process. Further research is necessary to investigate these preliminary results.

Design of a Robust Memristive Spiking Neuromorphic System with Unsupervised Learning in Hardware

2021 ◽  
Vol 17 (4) ◽  
pp. 1-26
Author(s):  
Md Musabbir Adnan ◽  
Sagarvarma Sayyaparaju ◽  
Samuel D. Brown ◽  
Mst Shamim Ara Shawkat ◽  
Catherine D. Schuman ◽  
...  
Keyword(s):  
Unsupervised Learning ◽  
Recognition Task ◽  
Single Layer ◽  
Process Variations ◽  
Spike Timing ◽  
System Level ◽  
Design Parameters ◽  
Digital Pulse ◽  
Neuromorphic System ◽  
The Impact

Spiking neural networks (SNN) offer a power efficient, biologically plausible learning paradigm by encoding information into spikes. The discovery of the memristor has accelerated the progress of spiking neuromorphic systems, as the intrinsic plasticity of the device makes it an ideal candidate to mimic a biological synapse. Despite providing a nanoscale form factor, non-volatility, and low-power operation, memristors suffer from device-level non-idealities, which impact system-level performance. To address these issues, this article presents a memristive crossbar-based neuromorphic system using unsupervised learning with twin-memristor synapses, fully digital pulse width modulated spike-timing-dependent plasticity, and homeostasis neurons. The implemented single-layer SNN was applied to a pattern-recognition task of classifying handwritten-digits. The performance of the system was analyzed by varying design parameters such as number of training epochs, neurons, and capacitors. Furthermore, the impact of memristor device non-idealities, such as device-switching mismatch, aging, failure, and process variations, were investigated and the resilience of the proposed system was demonstrated.

Making Up 3D Bodies

2021 ◽  
Vol 4 (2) ◽  
pp. 1-9
Author(s):  
Kiona Hagen Niehaus ◽  
Rebecca Fiebrink
Keyword(s):  
Software Tool ◽  
The Body ◽  
Design Parameters ◽  
Artistic Practice ◽  
Human Form ◽  
Modeling Systems ◽  
Exploratory Approach ◽  
Disability Status ◽  
High Level ◽  
The Impact

This paper describes the process of developing a software tool for digital artistic exploration of 3D human figures. Previously available software for modeling mesh-based 3D human figures restricts user output based on normative assumptions about the form that a body might take, particularly in terms of gender, race, and disability status, which are reinforced by ubiquitous use of range-limited sliders mapped to singular high-level design parameters. CreatorCustom, the software prototype created during this research, is designed to foreground an exploratory approach to modeling 3D human bodies, treating the digital body as a sculptural landscape rather than a presupposed form for rote technical representation. Building on prior research into serendipity in Human-Computer Interaction and 3D modeling systems for users at various levels of proficiency, among other areas, this research comprises two qualitative studies and investigation of the impact on the first author's artistic practice. Study 1 uses interviews and practice sessions to explore the practices of six queer artists working with the body and the language, materials, and actions they use in their practice; these then informed the design of the software tool. Study 2 investigates the usability, creativity support, and bodily implications of the software when used by thirteen artists in a workshop. These studies reveal the importance of exploration and unexpectedness in artistic practice, and a desire for experimental digital approaches to the human form.

scholarly journals Simulation Tests of a Cow Milking Machine—Analysis of Design Parameters

Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1358
Author(s):  
Ewa Golisz ◽  
Adam Kupczyk ◽  
Maria Majkowska ◽  
Jędrzej Trajer
Keyword(s):  
Mathematical Model ◽  
Simplified Model ◽  
Design Parameters ◽  
Degree Polynomial ◽  
Fourth Degree ◽  
Local Loss ◽  
Linear Drag ◽  
Milking Machine ◽  
Machine Analysis ◽  
The Impact

The objective of this paper was to create a mathematical model of vacuum drops in a form that enables the testing of the impact of design parameters of a milking cluster on the values of vacuum drops in the claw. Simulation tests of the milking cluster were conducted, with the use of a simplified model of vacuum drops in the form of a fourth-degree polynomial. Sensitivity analysis and a simulation of a model with a simplified structure of vacuum drops in the claw were carried out. As a result, the impact of the milking machine’s design parameters on the milking process could be analysed. The results showed that a change in the local loss and linear drag coefficient in the long milk duct will have a lower impact on vacuum drops if a smaller flux of inlet air, a higher head of the air/liquid mix, and a higher diameter of the long milk tube are used.

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