bluuebunny/crossref_metadata_2025 huggingface dataset:
ESTIMATION OF EFFECTIVENESSOF RADIOHYDROGEOLOGICAL MONITORING IN THE INFLUENCE ZONE OF KYIV RADIOACTIVE WASTE STORAGE
Authors:   Taras Shevchenko National University of Kyiv, Kyiv, Ukraine, Scherbak O. , Koshliakova T. ,   Taras Shevchenko National University of Kyiv, Kyiv, Ukraine, Dolin V. ,   Taras Shevchenko National University of Kyiv, Kyiv, Ukraine, Rudenko I. ,   State Institution "Institute of Environmental Geochemistry of NAS of Ukraine", Kyiv, Ukraine, Kutska Ya. ,   Taras Shevchenko National University of Kyiv, Kyiv, Ukraine
Published: February 2017

The current state of radiohydrogeological monitoring system in the influence zone of Kyiv subsurface radioactive waste storage is considered with using hydrogeological, statistical and geoinformatical research methods. According to monitoring observations (1992-2013) the spatialtemporal dynamics of the upper Quaternary – upper Eocene groundwater complex hydrodynamic regime is analyzed. Hydrogeofiltrational efficiency of the observation wells is estimated by two parameters, namely: the efficiency of uncovering of groundwater aquifer by filter section (filter position regarding the groundwater level and the rocks lithology in filter zone) and the transmissivity value. The presence of groundwater level downtrend and hydroizohypses spatial configuration changes were determined. The majority of observation wells are hydrogeofiltrational incomplete due to artificial mechanical mudding of the filter zone and structural features. Observational data provide little information and do not reflect the real impact of the storage on environment. Based on the results obtained the conclusion was made about the necessity of renewal and expansion of the current monitoring system. The monitoring system development must be made with taking into account the evolution of groundwater tritium contamination contours.
A comparative study of American ginseng (spp. Panax quinquefolius) and Donepezil on working memory in rats using scopolamine induced disruption of memory
Authors: Shende Shrikrishna S. , Shinde Kalbhairav M. , Tilak Abhijit V. , Rane Bhalachandra T. , Raveendran Siddhi , Dabhade Sanjay A.
Published: February 2017

Background: Treatment of Alzheimer’s disease (AD) includes acetylcholinesterase inhibitors like Donepezil. American ginseng has been postulated to enhance learning and memory owing to its antiapoptotic activity as well as inhibition of formation of β amyloid plaque. Scarce data is available on effect of combination of these two drugs. Hence, we have conducted this study to evaluate the same. Aim and objectives of the study were to evaluate the role of American ginseng on working memory in rats and to compare the effect of American ginseng with Donepezil on working memory in rats.Methods: Sprague-Dawley rats of either sex, weighing 150-200g were used and obtained from animal house of Dr. D. Y. Patil Medical College, Hospital and Research Centre, Pimpri, Pune. To study the effects of the drugs on working memory in rats, they were trained for conditioned avoidance response (CAR) using Cook's pole climbing apparatus. The method of Fellow and Cook was used.Results: In the group C (i.e. the control group), 50% of rats showed the retention of CAR. In the group S (i.e. only scopolamine group), only 20% of rats showed the retention of CAR. In the group S+AG (i.e. scopolamine and American ginseng), 60% of rats showed the retention of CAR. In the group S+ D (i.e. scopolamine and Donepezil) 70% of rats showed retention of CAR. In the group S+D+AG (i.e. the combination group of scopolamine, Donepezil and American ginseng), 80% of rats showed the retention of CAR.Conclusions: From this study we can conclude that American ginseng and Donepezil have comparable effects in retention of working memory. The combination of American ginseng and Donepezil can have additive effect on the retention of working memory.
Association of biophysical profile with neonatal outcome: an observational study
Authors: Singh Gurmeet , Sood Reena , Kaur Karandeep
Published: February 2017

Background: Perinatal asphyxia is a common cause of neonatal mortality and morbidity in India. Antenatal surveillance prevents foetal injury and death and improves long term neurological outcome through optimal timing of delivery while avoiding unnecessary interventions such as caesarean delivery or preterm delivery.Methods: After thorough history and physical examination, all patients underwent BPP assessment with USG and electronic foetal heart rate tracing and association between BPP score and various parameters were studied. Results: Low BPP scores were associated with low Apgar score, increased rate of neonatal admissions and increased neonatal deaths. For BPP score of 6 there were 5 deaths constituting 71.4% of the total cases.Conclusions: BPP score was found to be significantly associated with Apgar score and neonatal outcomes.
A study of anemia in primary hypothyroidism
Authors: Kulkarni Vrinda K. , Jadhav Dilip U.
Published: February 2017

Background: The association between anemia and hypothyroidism has been recognized, although the prevalence of anemia in hypothyroid patients varies widely between studies. The main objectives were to study the prevalence, type, etiology of anemia in primary hypothyroidism and to correlate severity of anemia with severity of hypothyroidism.Methods: A case control study was carried out in a tertiary care hospital. Newly diagnosed 60 overt primary hypothyroid patients and 180 euthyroid controls were evaluated for anemia. Morphological types of anemia, their etiology were studied. Severity of anemia was correlated with that of hypothyroidism.Results: Anemia was observed in 45 patients with hypothyroidism. Symptoms due to anemia were significantly higher in cases than in the anemic controls. RBC morphology showed normocytic normochromic in 39, microcytic hypochromic in 14 and macrocytic in 7 cases. Serum iron was significantly lower in the cases than in the controls. Serum anti-TPO positivity was 63.33% in cases as compared to 10% in controls. Anemia was severe in cases with high TSH.Conclusions: The prevalence of anemia was 75% which was higher than that seen in the euthyroid controls. Hypothyroid patients were more symptomatic for anemia than the controls. Normocytic normochromic type of anemia was the most common type in our study. Autoimmunity in the form of anti-TPO positivity was detected in 69% of anemic cases. Iron deficiency was observed in the cases more than in the controls. There was a statistically significant negative correlation between TSH and hemoglobin.
Alternative uses of dermoscopy in general dermatology
Authors: Papakonstantinou Eleni , Raap Ulrike
Published: February 2017

Over the last few years, dermoscopy has been shown to be an effective diagnostic tool in assisting the noninvasive diagnosis not only of skin tumors but also of various general dermatological disorders. The use of dermoscopy has offered a new morphological dimension supporting the diagnosis and clinical follow-up of several dermatological conditions. Within the last years, dermoscopy is gaining ground in general dermatology as well. Among the large spectrum of skin infections, specific dermoscopic patterns have been described for common skin infections such as viral warts, molluscum contagiosum, scabies, and pediculosis, as well as for tinea nigra, tungiasis, and cutaneous larva migrans. Also, common skin disorders such as psoriasis, pityriasis rosea or lichen planus show characteristic dermoscopic patterns. The aim of this article is to provide an overview of the use of dermoscopy in general dermatology by analyzing the dermoscopic differential diagnosis of relatively common dermatological   disorders grouped according to their clinical characteristics.
Reliability and Validity of the Sexual Experiences Survey–Short Forms Victimization and Perpetration
Authors: Johnson Shannon M. , Murphy Megan J. , Gidycz Christine A.
Published: February 2017

The Sexual Experiences Survey (SES), the most widely used measure of unwanted sexual experiences, was recently updated (Koss et al., 2007). The purpose of this study was to provide psychometric data on the updated Sexual Experiences Survey–Short Form Perpetration (SES-SFP) and the Sexual Experiences Survey–Short Form Victimization (SES-SFV). Men (n = 136) and women (n = 433) were randomly assigned to in-person or Internet formats of administration for 3 measurement points. Women completed victimization surveys and trauma measures. Men completed perpetration surveys and attitude/personality measures. Results supported the validity and reliability of both the SES-SFV with women and the SES-SFP with men. Further research is needed regarding the use of the SES-SFV with men and the SES-SFP with women.
A Foundational Analysis of Dorothea Orem's Self-Care Theory and Evaluation of Its Significance for Nursing Practice and Research
Authors: Younas Ahtisham
Published: February 2017

In-depth understanding of the ontological and epistemological assumptions of nursing theories can be achieved through theory analysis. Several theory analysis criteria have been proposed for examining ontological and epistemological assumptions, but there are limited examples of actual analysis of these assumptions. This article presents an analysis of the ontological and epistemological assumptions of Dorothea Orem's self-care theory and evaluates its significance for nursing practice and research.
The Effect of Preoperative Education on Postoperative Pain after Joint Surgery: An Integrative Literature Review
Authors: Barry Mary Ashley
Published: February 2017

As the number of total knee arthroplasty surgeries continues to increase and the length of hospital stay is trending down, preoperative education continues to be an important factor to support positive postoperative outcomes. The purpose of this literature review is to examine whether preoperative education for patients undergoing total knee arthroplasty affects postoperative pain management compared to those who do not receive this education. Findings from the literature review indicate that receiving preoperative education before a total knee arthroplasty does not impact pain management in the postoperative phase.
Deference to Expertise: Making Care Safer
Authors: Godlock Gwendolyn Cherese , Miltner Rebecca Suzie , Sullivan Dori Taylor
Published: February 2017

Since the seminal report by the Institute of Medicine, To Err Is Human, was issued in 1999, significant efforts across the health care industry have been launched to improve the safety and quality of patient care. Recent advances in the safety of health care delivery have included commitment to creating high-reliability organizations (HROs) to enhance existing quality improvement activities. This article will explore key elements of the HRO concept of deference to expertise, describe the structural elements that support nurses and other personnel in speaking up, and provide examples of practical, evidence-based tools to help organizations support and encourage all members of the health care team to speak up.
Applying the Social Ecological Model and Theory of Self-Efficacy in the Worksite Heart Health Improvement Project-PLUS
Authors: Doran Kelly , Resnick Barbara , Kim Natalie , Lynn Donna , McCormick Tyrell
Published: February 2017

Background: Long-term care (LTC) employees are at high risk for cardiovascular disease. Despite the documented benefits of worksite health promotion (WHP) programs for employees and employers and the potential benefits to residents in LTC facilities, LTC employees are rarely offered WHP programs. Purpose: The purpose of the intervention described in this article is to reduce cardiovascular disease risk factors among LTC workers using a physical activity, nutrition, and stress management WHP implemented during paid work time with 98 LTC staff members. Methods: This article describes a 9-month physical activity, nutrition, and stress management WHP intervention delivered during paid work time to reduce the cardiovascular disease risk of employees working in LTC. The intervention is rooted in the social ecological model and social cognitive theory. The intervention is based on formative research and evidence-based practice recommendations and is specifically designed to reduce barriers to intervention participation (e.g., inconsistent break times and unpredictable resident care needs) and enhance motivators to program participation (e.g., enhanced social support). Results: The intervention is ongoing, but measures are described. Conclusion: As more employers offer WHP programs, it is important that programs are tailored to meet specific employee groups and work environments. This article operationalizes a WHP research protocol with LTC employees that can be applied to reduce cardiovascular disease risk in LTC employees or similar employee groups in similar work environments.
Peran Perempuan dalam Perencanaan Keluarga Responsif Gender Berbasis Agama di Desa Mulyo Rejo Kecamatan Sungai Lilin Kabupaten Musi Banyuasin
Authors: Antasari Rina
Published: February 2017

Tulisan ini judul “Peran Perempuan Dalam Perencanaan Keluarga Responsif Gender Berbasis Agama Di Desa Mulyo Rejo Kecamatan Sungai Lilin Kabupaten Musi Banyuasin”. Diawali dari hasil observasi dan pemikiran tentang perlunya dilakukan pengkajian lebih mendalam tentang hukum keluarga dalam kaitannya dengan hubungan relasi gender dalam keluarga pada masyarakat Desa Mulyo Rejo Kecamatan Sungai Lilin. Agar tujuan PAR tercapai yakni: (1) agar terwujudnya keluarga yang responsive gender yakni keluarga yang telah memperhatikan kebutuhan keluarga tanpa adanya diskriminasi, (2) adanya perubahan dan perilaku/tindakan sosial langsung yang bermula dari keluarga, (3) penambahan pengetahuan mengenai situasi keluarga yang responsif gender yang terencana dan penambahan kemampuan bagi dampingan untuk mengubah situasi mereka mewujudkan keluarga yang responsif gender berbasis agama, maka program aksi riset ini dilakukan dengan menggunakan strategi dan langkah-langkah PAR. Sebagaian kecil warga dampingan sudah mulai menerapkan pengetahuan mengenai perencanaan keluarga responsif gender berbasis agama dalam keluarga mereka terutama melalui peran isteri bersama suami.This paper entitled "The Role of Women in Responsive Gender of Family Planning Based on Religion in Mulyo Rejo Village Sungai Lilin Musi Banyuasin". Starting from the observation and thought about the need to do much broader about family law in relation to gender relationships within the family in society of Mulyo Rejo village in Sungai Lilin. For the purpose of PAR achieved as follows: (1) for the realization of the family that has responsive gender, i.e families who have noticed the family's needs without discrimination, (2) the changes and behavioral / social action directly originate from the family, (3) the addition of knowledge concerning the family situation on responsive gender planned and the addition of capabilities for assistance to change their situation embodies responsive gender in family based on religion, then the action program of research is done by using strategies and measures PAR. Small part of residents has started to apply knowledge of responsive in family planning based on religion in their families, especially through the role of the wife with her husband.
Konsep Ketuhanan (T’ien) dan Relevansinya dengan Pembentukan Etos Kerja dalam Ajaran Kong Hu Cu (Konfusius)
Authors: Nazwar Nazwar
Published: February 2017

Artikel ini membahas konsep Ketuhanan Konfusius yang berkaitan dengan etika kerja para penganutnya. Konsep ketuhanan yang dianalisa berdasar pada perspektif Filsafat, kemudian ditarik kepada realita tindakan sosial penganut ajaran Konfusius, dengan menggunakan data yang diperoleh berupa semangat kerja dan pemenuhan kebutuhan hidup para penganut pandangan hidup ini. Berdasarkan hasil penelitian, ditemukan bahwa konsep ketuhanan yang terdapat dalam ajaran Konfusius adalah paradigma fungsional. Dalam keyakinan tersebut, relasi antara Tuhan dan manusia didasarkan pada nilai fungsi. Tuhan diyakini berdasar pada peranannya terhadap kehidupan manusia. Begitupun sebaliknya, manusia diyakini berperan dalam pemenuhan keinginan Tuhan. Sehingga dalam ibadahnya yang paling menonjol adalah ritual korban. Semakin banyak korban yang dipersembahkan, maka kehidupanpun akan semakin subur dan makmur. Berdasarkan paradigma demikian, para penganut Konfusius kemudian mempunyai semangat kerja tinggi. Dengan tujuan selain  pemenuhan kebutuhan hidup, juga merupakan usaha pemenuhan kebutuhan spiritual dalam rangka ibadah kepada T’ien (Tuhan).This article discusses the concept of God Confucius relating to the work ethic of its adherents. The concept of God that is analyzed based on the perspective of philosophy, then pulled to the reality of social action adherents of Confucianism, using the data obtained in the form of morale and subsistence adherents of this view of life. Based on this research, it was found that the concept of God contained in the teachings of Confucius is the functional paradigm. In that belief, the relationship between God and man is based on the value of the function. God is believed, based on its role in human life. Vice versa, humans are believed to play a role in the fulfillment of God's will. Thus, in the worship of the most prominent is the ritual sacrifice. The more sacrifices be offered, the more fertile and prosperous life will be. Based on such a paradigm, the Confucians then have a high morale. For purposes other than the needs of life, is also a spiritual business needs in order to the worship to T'ien (God).
Curriculum Development of Madrasah Tahfidz-Based Pesantren
Authors: Husna Nawa , Arifin Zainal
Published: February 2017

The purpose of the research was to know deeper about the concept of Madrasah tahfidz based Pesantren with 30 chapters of tahfidz al-Qur’an system and to know how the implementation of curriculum development of madrasah tahfidz based Pesantren (school boarding) in MITQ TBS Kudus, Central Java. The research was a descriptive-qualitative with phenomenological approach with data collection techniques: in-depth interviews, non-participant observation, and documentation. The analysis of the data was by reduction, display, and provided conclusions. The results showed (1) the concept of madrasah tahfidz based pesantren in MITQ TB Kudus, Central Java emphasized on the time allocation of tahfidz al-Qur’an with more portion such as 48 hours per week to reach tahfidz al-Qur'an 30 chapters, and (2) curriculum development of madrasah tahfidz  based Pesantren (school boarding) in TBS MITQ Kudus, Central Java included: diagnosis of needs, development of education purposes, curriculum of KTSP, curriculumof  Religion Ministry and the local curriculum (pesantren), learning experiences, and the development of curriculum evaluation.Penelitian ini bertujuan untuk mengetahui lebih mendalam mengenai konsep madrasah  tahfidz berbasis pesantren dengan sistem tahfidz al-Qur’an 30 juz serta mengetahui bagaimana pelaksanaan pengembangan kurikulum madrasah tahfidz berbasis pesantren di MITQ TBS Kudus Jawa Tengah. Penelitian ini adalah penelitian deskriptif-kualitatif dengan pendekatan fenomenologi dengan teknik pengumpulan data: wawancara mendalam, observasi non partisipan, dan dokumentasi. Analisis data melalui reduksi, display, dan memberikan kesimpulan. Hasil penelitian menunjukkan (1) konsep madrasah tahfidz berbasis pesantren di MITQ TBS Kudus Jawa Tengah menekankan pada alokasi waktu tahfidz al-Qur’an dengan porsi lebih yaitu 48 jam perminggu untuk mencapai tahfidz al-Qur’an 30 juz, dan (2) pengembangan kurikulum madrasah tahfidz berbasis pesantren di MITQ TBS Kudus Jawa Tengah meliputi: diagnosis kebutuhan, pengembangan tujuan pendidikan, kurikulum KTSP, kurikulum Kementerian Agama dan kurikulum muatan lokal (pesantren), pengalaman belajar, dan pengembangan evaluasi kurikulum.
La Maestría en Gestión de Servicios de Salud: un programa de liderazgo y toma de decisiones
Authors: Paredes-Gómez Carlos , Bueno-Balaguer Luz Amanda , Martínez-Marín Rocío Del Pilar
Published: February 2017

The Master of Health Services Management at the Universidad de Santander requested and obtained the official registration in 2010 in the modality of professional master’s degree. In this sense, the program seeks the advanced development of skills that allow the solution to problems or the analysis of particular situations of a disciplinary and interdisciplinary nature, through the assimilation and appropriation of knowledge, methodology and scientific, technological or Artistic development; its degree work requirement is oriented to applied research or to develop a case study.
Karakterisasi Kemiripan Genetik Koleksi Inbrida Jagung Berdasarkan Marka Mikrosatelit
Authors: Pabendon Marcia Bunga , Dahlan M. , Sutrisno Sutrisno , George M. L.C.
Published: February 2017

Information on genetic relationships among available crop germplasm such as maize inbred lines, has important implications to breeding programs. A set of 26 maize inbreds togeher with six standard lines from CIMMYT (CML51, CML292, CML202, CML206, CML236, dan CML396), was characterized using 26 SSR markers, which were coverage of the maize genomes. The objective of this study was to analyze genetic diversities among the Indonesian maize inbred collections. Polymorphism Information Content (PIC) value and the observed genetic distance indicated the existence of large variabilities among the inbreds. Cluster analysis based on 27% of the Jaccard’s similarity coefficient placed the inbreds into three groups. Genetic distances among all the possible pairs without the standard maize lines varied from 0.32 (KSX360F2-5-1-3-1v vs KSX2601F2-5-1-1-v) to 0.88 (PT963298-1-B-B-Bv vs Mr13). Cluster and Principal Coordinate Analysis of the genetic distances, revealed a clear differentiation of the inbred lines into groups according to their source populations. This clustering were consistent with those of the known pedigree records of the inbreds based on their morphological characters. These results support the use of morphological traits in the production of maize hybrids. The SSR markers proved to be effective to characterize, identify, and demonstrate genetic similarities among the maize inbred lines.
Phylogenetic and Maturity Analyses of Sixty Soybean Genotypes Used for DNA Marker Development of Early Maturity Quantitative Trait Loci in Soybean
Authors: Tasma I Made , Satyawan Dani , Warsun Ahmad , Yunus Muhamad , Santosa Budi
Published: February 2017

Phylogenetic and Maturity Analyses of Sixty Soybean
Genotypes Used for DNA Marker Development of Early
Maturity Quantitative Trait Loci in Soybean. I Made
Tasma, Dani Satyawan, Ahmad Warsun, Muhamad
Yunus, and Budi Santosa. The Indonesian soybean
productivity is still very low with the national average of 1.3
t/ha. One means to improve national soybean productivity is
by manipulating harvest index by cultivating very early
maturing soybean cultivars. Development of early maturing
soybean cultivars can be expedited by using marker-aided
selection. The objective of this study was to select parental
lines having contrasted maturity traits and selected parents
must be genetically distance. The parents then were used to
develop F2 populations for detecting early maturity QTL in
soybean. Maturity tests of 60 soybean genotypes were
conducted at two locations, Cikeumeuh (Bogor) and Pacet
(Cianjur) using a randomized block design with three
replications. Genomic DNA of the 60 genotypes were
analyzed using 18 SSR markers and genetic relationship was
constructed using the Unweighted Pair-Group Method
Arithmatic through Numerical Taxonomy and Multivariate
System program version 2.1-pc. Results showed that the 60
genotypes demonstrated normal distribution in both
locations for days to R1 (32-48d), days to R3 (35-55d), days to
R7 (75-92d), and days to R8 (78-99d). Four early maturing
genotypes and three late genotypes were obtained. Total
SSR alleles observed were 237 with average allele per locus
of 12.6 (3-29), and average PIC value of 0.78 (0.55-0.89).
Genetic similarity among genotypes ranges from 74.8-95%.
At similarity level 77% divided the genotypes into six clusters
(the four selected early maturing genotypes located in
clusters III and IV, while the three late genotypes located in
cluster II). Based on maturity data, pubescent color, and
phygenetic analysis seven parents were selected (four early
maturing genotypes B1430, B2973, B3611, B4433 and three
late genotypes B1635, B1658, and B3570). Twelve F2
populations were developed with the aid of SSR markers
Satt300 dan Satt516. Two of the populations will be used to
develop DNA markers for earliness in soybean.
Methodology to Estimate the Economic Impact of Intelligent Wells Considering Reservoir Uncertainties
Authors: Morais V. L. , Fioravanti A. R. , Schiozer D. J.
Published: February 2017

This work presents a method to test the use of intelligent wells in probabilistic scenarios. The proposed algorithm assists the decision about the number, position and operation of the interval control valves (ICV). The procedure focuses on the evaluation of intelligent well controls when optimizing complex oil field production strategies considering geological uncertainties.

The method assists the ICV application in uncertain scenarios, seeking to enhance flexibility and to improve the expected monetary value (EMV) during the field development phase. This work presents a detailed analysis of a production strategy previously optimized for conventional wells. The algorithm divides the production period into smaller time sections and optimizes them individually in a time sequence. For each section, performance indicators evaluate wells and regions for the potential to install ICV. We simulate the different combinations only of promising regions, restricting search space, which results in fewer simulation runs.

We used the benchmark case UNISIM-I-D, which is based on the Namorado field (Campos Basin, Brazil). EMV of the representative models was the objective function and we optimized ICV controls for a long-term exploitation strategy (lifecycle optimization procedure). We compared the proposed proactive control with an optimized reactive control to assess the results.

The study considers two different platform capacities (one optimized for the conventional well strategy and one with reduced capacity). We also show that when a platform restricts water production, the ICV closure affects not only the nearest wells but also other wells with high water rates, so this also must be evaluated.

Most ICV studies use techniques that are computationally expensive in real field evaluations. Barreto and Schiozer (2015) optimizes ICV placement with a low number of simulations but they check the viability of a single ICV implementation in each cycle. We propose testing various ICV simultaneously, respecting the influence of cross parameters by partitioning the production period into a sequence of predetermined time sections and optimizing each time section individually, forward in time.

The proposed optimization process demands a feasible number of simulation runs, enabling use in practical applications and complex reservoirs.
Model-Based Multi-Objective Optimization Methods for Efficient Management of Subsurface Flow
Authors: Fu Jianlin , Wen Xian-Huan
Published: February 2017

Multi-objective optimization (MOO) that accounts for several distinct, possibly conflicting, objectives is expected to be capable of providing improved reservoir management (RM) solutions for efficient oil field development owing to the overall optimization of subsurface flow. Considering the complexity and diversity of MOO problems in model-based RM, we develop three MOO methods (MOAdjoint, MOGA, and MOPSO) in this work to address various oil field development problems. MOAdjoint combines a weighted sum technique with a gradient-based method for solving large-scale continuous problems that have thousands of variables. An adjoint method is used to compute efficiently the derivatives of objective functions with respect to decision variables and a sequential quadratic programming method is used for optimization search. MOGA is a population-based method, which combines a Pareto-ranking technique with genetic algorithm (GA) to address small-scale discrete problems. MOPSO is another population-based method, which combines a Pareto-ranking technique with particle swarm optimization (PSO) for a wide spectrum of optimization problems. Their advantages and disadvantages are highlighted. An example is used to compare the three methods. Results show that MOPSO seems particularly suitable for medium-scale RM problems, mainly because of its relatively high rate of convergence and efficient recovery of Pareto front.
Trajectory-Based DEIM TDEIM Model Reduction Applied to Reservoir Simulation
Authors: Tan Xiaosi , Gildin Eduardo , Trehan Sumeet , Yang Yahan , Hoda Nazish
Published: February 2017

Two well-known model reduction methods, namely the trajectory piecewise linearization (TPWL) approximation and the discrete empirical interpolation method (DEIM) are combined to utilize their benefits and avoid their shortcomings to generate reduced order models for reservoir simulation. To this end, we use the trajectory-based DEIM (TDEIM) to approximate the nonlinear terms in the simulation. Specifically, the nonlinear terms in the test simulation can be expressed as the sum of the nonlinear terms evaluated at the closest available training point from the high-fidelity training trajectory and a perturbed term defined as the difference between the the test and the training terms. We only interpolate this perturbed term in the reduced space of DEIM instead of the original nonlinear term, resulting in computational savings and improvement in accuracy. TDEIM is further combined with the proper orthogonal decomposition (POD) method to provide an efficient POD-TDEIM framework. We test our new methodology on two examples, involving two-phase (water-oil) heterogeneous reservoir models. First, the performance of POD-TDEIM is compared with POD-TPWL and POD-DEIM on a 2D reservoir model. For the same set of high-fidelity training runs, POD-TDEIM outperforms the other two methods. We further propose an extended TDEIM in which the nonlinear term is expanded along the training trajectory to include one more derivative term. An example with a 3D reservoir model is then presented to show the capability of the extended TDEIM to further improve the accuracy of the reduced model.
A Gauss–Newton Trust Region Solver for Large Scale History Matching Problems
Authors: Gao Guohua , Jiang Hao , Hagen Paul Van , Vink Jeroen C. , Wells Terence
Published: February 2017

Solving the Gauss-Newton trust region sub-problem with traditional solvers involves solving a symmetric linear system with dimensions the same as the number of uncertain parameters, and it is extremely computational expensive for history matching problems with large number of uncertain parameters. A new trust region (TR) solver is developed to save both memory usage and computational cost, and its performance is compared with the well-known direct TR solver using factorization and iterative TR solver using conjugate-gradient approach.

The original Gauss-Newton trust region sub-problem involves solving linear system with the number of uncertain parameters. With application of the matrix inverse lemma, it is transformed to a new problem that involves solving linear system with the number of observed data. For history matching problems where the number of uncertain parameters is much larger than the number of observed data, both memory usage and CPU time can be significantly reduced when compared to solving the original problem directly. An auto-adaptive power-law transformation technique is developed to transform the original strong nonlinear function to a new function that behaves more like a linear function. Finally, the Newton-Raphson method with some modifications is applied to solve the trust region sub-problem.

The proposed approach is applied to find best-match solutions in Bayesian style assisted history matching problems. It is first validated on a set of synthetic test problems with different numbers of uncertain parameters and different numbers of observed data. In terms of efficiency, the new approach is shown to significantly reduce both the computational cost and memory usage, e.g., by a factor of more than 10, when compared to the direct TR solver of the GALAHAD optimization library. In terms of robustness, the new approach is able to reduce the risk of failure to find the right solution significantly, when compared to the iterative TR solver of the GALAHAD optimization library. Our numerical results indicate that the new solver can solve large scale trust region sub-problems using reasonably small amounts of CPU time (in seconds) and memory (in MB). Compared to the CPU time and memory used for completing one reservoir simulation run for the same problem (in hours and in GB), the cost for finding the best-match parameter values using our new trust region solver is negligible. The proposed approach has been implemented in our in-house reservoir simulation and history matching system and has been validated on a real reservoir simulation model. This illustrates the main result of this paper: the development of a robust Gauss-Newton trust region approach, which is applicable for large scale history matching problems with negligible extra cost in CPU and memory.
A Localized Variable Switching Method for Mass-Variable Based Reservoir Simulators
Authors: Alpak Faruk O. , Vink Jeroen C.
Published: February 2017

Field-scale simulations of complex processes, often suffer from long simulation times. One of the main reasons is that the Newton-Raphson (NR) process used to solve each simulation time step requires many iterations and small time-step sizes to converge. Since the selection of solution variables impacts the nonlinearity of the equations, it is attractive to have a practical method to rapidly explore the use of alternative primary variables in general-purpose reservoir simulators.

Many reservoir simulators use pressure, saturations, and temperature in each gridblock as primary solution variables, which are referred to as natural variables. There is also a class of reservoir simulators that uses pressure, total component masses (or moles), and internal energy in each gridblock as primary variables. These simulators are referred to as mass-variable based reservoir simulators. For a given choice of primary variables, most simulators have dedicated, highly optimized procedures to compute the required derivatives and chain rules required to build the Jacobian matrix. Hence, it is usually not possible to switch between mass and natural variables. In this work, however, we establish a link at the numerical solution level between naturaland mass-variable formulations and design a novel (nonlinear) block-local method that transforms mass-variable shifts (computed at each NR iteration) into equivalent natural variable shifts.

We demonstrate on a number of simulation models of various complexity that, by use of the proposed approach, a mass-variable based flow simulator can still effectively use natural variables, where the change of variables can be made locally per gridblock. Results indicate that in some models the total number of NR iterations, linear solver (LS) iterations, and backups are reduced when using natural variables, instead of mass variables. However, the improvement is fairly modest and not generally observed. Our findings also signify that, depending on the specific characteristics of the simulation problem at hand, mass-variable based simulators may perform comparably or outperform natural-variable based simulators.

The proposed variable switching method can be used effectively to evaluate the impact of using different primary solution variables on problem nonlinearity and solver efficiency. With this method, the impact of interchanging primary solution variables on problem nonlinearity can be rapidly evaluated.
Quantifying Value of Information using Ensemble Variance Analysis
Authors: He Jincong , Sarma Pallav , Bhark Eric , Tanaka Shusei , Chen Bailian , Wen Xian-Huan , Kamath Jairam
Published: February 2017

Data acquisition programs such as surveillance and pilots play an important role in minimizing subsurface risks and improving decision quality for reservoir management. In order for design optimization and investment justification of these programs, it is crucial to be able to quantify the expected uncertainty reduction and the value of information (VOI) attainable from a given design. This problem is challenging as the data from the acquisition program is uncertain at the time of the analysis. In this paper a method called ensemble variance analysis (EVA) is proposed. Based on a multi-Gaussian assumption between the observation data and the objective function, the EVA method quantifies the expected uncertainty reduction from covariance information that is estimated from an ensemble of simulations. The result of EVA can then be used with a decision tree to quantify the VOI of a given data acquisition program.

The proposed method has several novel features compared to existing methods. Firstly, the EVA method considers data-objective function relationship directly. Therefore it can handle nonlinear forward models and an arbitrary number of parameters. Secondly, for cases when the multi-Gaussian assumption between the data and objective function does not hold, the EVA method still provides a lower bound on expected uncertainty reduction, which can be useful in providing a conservative estimate of the surveillance/pilot performance. Finally, EVA also provides an estimate of the shift in the mean of the objective function distribution, which is crucial for VOI calculation. In this paper, the EVA workflow for expected uncertainty reduction quantification is described. The result from EVA is benchmarked with recently proposed rigorous sampling methods, and the capacity of the method for VOI quantification is demonstrated for a pilot analysis problem using a field-scale reservoir model.
An Efficient Fully-Implicit MFD-MUSCL Method Based on a Novel Multislope Limiting Procedure
Authors: Jiang Jiamin , Younis Rami M.
Published: February 2017

Standard reservoir simulation schemes use single-point upstream weighting for computing the convective fluxes when multi-phase/component fluids are present. These schemes are only first-order and may cause high viscosity effect. Second-order schemes provide a better resolution and reduce the smoothing near the shocks. In reservoir simulation practice, implicit discretisations capable of taking large time steps are preferred over explicit schemes. However, even for a simple first-order method, solving a large nonlinear system is often very expensive; Extra coupling and nonlinearity of the discretised equations can be introduced from a higher-order spatial discretisation. It has been shown that strong nonlinearity as well as lack of continuous differentiability in numerical flux function and flux limiter can cause serious nonlinear convergence problem.

Cell-centered finite-volume (CCFV) discretizations may offer several attractive features, especially for fluid flow in heterogeneous or fractured porous media. The objectives of this work are to develop a fully-implicit CCFV framework that could achieve second-order spatial accuracy on smooth solutions, while at the same time maintain robustness and nonlinear convergence performance. We develop a novel multislope MUSCL method which interpolates the required values at the edge centroids in a simpler way by taking advantage of some geometric features of the triangular mesh. Through the edge centroids, the numerical diffusion caused by mesh skewness is significantly reduced, and optimal second-order accuracy can be achieved. An improved gradually-switching piecewise-linear flux-limiter is introduced according to mesh non-uniformity in order to prevent spurious oscillations. The smooth flux-limiter can achieve high accuracy without degrading nonlinear convergence behavior.

For the discretization of pressure and Darcy velocities, a mimetic finite difference method that provides flux- continuity and an accurate total velocity field is used. The fully-coupled MFD-MUSCL framework is adapted to accommodate a lower-dimensional discrete fracture-matrix (DFM) model. Several numerical tests with discrete fractured system are carried out to demonstrate the efficiency and robustness of the numerical model. The results show that the high-order MUSCL method effectively reduces numerical diffusion, leading to improved resolution of saturation fronts compared with the first-order method. In addition, it is shown that the developed multislope method and adaptive flux limiter exhibit superior nonlinear convergence compared with other alternatives.
Enhanced Constrained Pressure Residual ECPR Preconditioning for Solving Difficult Large Scale Thermal Models
Authors: Li Gary , Wallis John
Published: February 2017

The Constrained Pressure Residual (CPR1,2) preconditioning method with FGMRES3 acceleration, although very efficient for iterative solution of isothermal fully implicit linear systems, may encounter significant convergence difficulties for large scale thermal cases. This is in part due to the fact that for these problems pressures are not the only strong variables. For such cases this paper describes an enhanced version of CPR (ECPR) preconditioning which is simple to implement and can significantly decrease iterations by 50% −80% or more depending on problem difficulty, converge where CPR fails, and substantially reduce work.

The two-stage ECPR preconditioning uses an expanded variable set for the first stage. The key step involves a fast strong variable selection algorithm which can substantially increase the robustness of CPR. For the approximate solution of this enhanced first stage we used FGMRES with equilibrated ILUC as the preconditioning. The improved strength of this step allows the use of a less expensive second stage preconditioning such as block ILU(0) rather than block ILU (1)2.

The block ILU(0) /ECPR method showed significant improvement in convergence rate for these difficult thermal cases over the original block ILU(1)/CPR method. We observed over 50% reduction in the number of iterations for our moderately difficult test cases over entire runs and reduction in run times. For individual linear systems requiring many CPR iterations test cases show iterations can be reduced by 80% or more using ECPR. In one particular test case CPR failed to converge after 100 iterations but ECPR converged in 7 iterations.
A General Modeling Framework for Simulating Complex Recovery Processes in Fractured Reservoirs at Different Resolutions
Authors: Hui Mun-Hong Robin , Karimi-Fard Mohammad , Mallison Bradley , Durlofsky Louis J.
Published: February 2017

A comprehensive methodology for gridding, discretizing, coarsening, and simulating discrete-fracture-matrix models of naturally fractured reservoirs is described and applied. The model representation considered here can be used to define the grid and transmissibilities, at either the original fine scale or at coarser scales, for any connectivity-list-based finite-volume flow simulator. For our fine-scale mesh, we use a polyhedral gridding technique to construct a conforming matrix grid with adaptive refinement near fractures, which are represented as faces of grid cells. The algorithm uses a single input parameter to obtain a suitable compromise between fine-grid cell quality and the fidelity of the fracture representation. Discretization using a two-point flux approximation is accomplished with an existing procedure that treats fractures as lower-dimensional entities (i.e., resolution in the transverse direction is not required). The upscaling method is an aggregation-based technique in which coarse control volumes are aggregates of fine-scale cells, and coarse transmissibilities are computed using a general flow-based procedure. Numerical results are presented for waterflood, sour gas injection, and gas condensate primary production. Coarse-model accuracy is shown to generally decrease with increasing levels of coarsening, as would be expected. We demonstrate, however, that by using our methodology, two orders of magnitude of speedup can be achieved with models that introduce less than about 10% error (with error appropriately defined). This suggests that the overall framework may be very useful for the simulation of realistic discrete-fracture-matrix models.
Non-Equilibrium Reservoir Simulation of Solvent-Steam Processes, Based on Mass and Heat Transfer Inside a Pore
Authors: Bayestehparvin Bita , Abedi Jalal , Ali S. M.
Published: February 2017

Steam processes involving injection of a solvent with steam, such as CSS (Cyclic Steam Stimulation), SAGD (Steam-Assisted Gravity Drainage), and steam injection in isothermal mode are currently receiving a great deal of attention in Alberta. These combination processes are designed to reduce energy consumption and the emission of greenhouse gases over steam alone. Field results have been mixed and the original intent remains elusive. This paper addresses questions regarding the mechanism of solvent dissolution of bitumen and the expected improvement in oil recovery, if any, when a solvent is injected with steam.

The unique aspect of this work is that instantaneous phase equilibrium is not assumed, as is customary in numerical simulators for solvent-steam applications. Nor is partial equilibrium assumed based on an empirical factor or concept. Rather, equilibrium is based on an analytical model of the dissolution and mobilization of a drop of bitumen inside a pore by solvent and heat. The results of this part of the study show that solvent requires at least three times as long to mobilize bitumen as by heat conduction. Such a delay is implicit in the nature of diffusion and dispersion of a solvent. Several boundary conditions are tested for a spherical drop.

A new thermal compositional simulator with the single drop model was developed for this study and several thermal processes for solvent injection were investigated for non-equilibrium phase behaviour. The results were compared to the case of instantaneous equilibrium, confirming the reason for the lack of success with solvent injection.

The results and extensions of this work will be of great interest in heavy oil production because they serve to explain the expected performance and frequent lack of success in solvent-steam injection. Use of the developed simulator would make it possible to determine whether solvent injection is a good choice in a given situation.
Unveiling the Causes of Fingering in Steam-Assisted Heavy Oil Recovery - Linear Instability Analysis and Numerical Simulation
Authors: Zhu Da , Gates Ian D.
Published: February 2017

Given the high viscosity of the oil, bitumen from oil sands reservoirs in western Canada is recovered by using steam which, due to its temperature, lowers its viscosity. One of the key issues faced by the operators is the steam conformance of the depletion chamber around wells. The greater the fingering phenomena of steam at the edge of chamber, the worse is the chamber uniformity and utilization of the well, and the greater are the green house gas emissions and water use per unit oil recovered. Fingering has long been explained as the penetration of steam phase into the oil phase which arises from an unfavourable mobility ratio. In this paper, we introduce linear instability analyses (Orr-Sommerfeld and Rayleigh-Taylor/Saffman-Taylor instability) of the interface between steam and oil layers and conduct a series of numerical simulations to reveal that fingering in the steam-assisted heavy oil recovery at the top of the steam chamber is created due to solution gas exsolution whereas fingering at the chamber edge is due to viscous shear instability. The results show that non-ideal steam conformance is inevitable even in homogeneous reservoirs.