bluuebunny/crossref_metadata_2025 huggingface dataset:
Environment Biological and Health Care Efforts Influenced of Lymfatic Filariasis Incidence, Sarmi Distric
Authors: Sipayung Mina , Wahjuni Chatarina Umbul , Devy Shrimarti
Published: April 2018

ABSTRACTDistrict Sarmi is the most endemic area of filariasis in Papua which has rate of microfilaria (mf) (47.06%) up to the year2012. In the Province Papua filarial worm is Wuchereria bancrofti and is transmitted through the bite of a mosquito vectors. Lymphatic filariasis does not cause death, but in chronic cases it causes disability, psychosocial problems, stigma, and decreased productivity. This study was aimed to analyze environment biological and health care efforts that influence the incidence of lymphatic filariasis. This study used case-control method. Samples comprised 32 case samples (mf +) and 32 control samples (mf-). Primary data were collected through interviews and observation. Data were analyzed using Chi-Square and continued with multivariate Logistic Regression. Statistical analysis obtained indicated two variables on the incidence of lymphatic filariasis limfatik in District Sarmi (health care efforts pvalue = 0.002, OR: 7.779, as well as the biological environment pvalue= 0.008, OR: 5.841). Significant variables were health services with sub-variables promotion, prevention and the environmental biology. Suggestion: Mosquito bites should be avoided, the vector should be controlled through mutual cooperation and health promotion should be implemented.Keywords: Wuchereria bancrofti, lymphatic filariasis, vector, health care,                         Sarmi Distric
System Analysis of Dengue Virus Surveillance in BBTKL PP Surabaya Year 2012–2014
Authors: Husnayain Atina , Artanti Kurnia Dwi , Zaenal Acub
Published: April 2018

Changing the distribution of dengue virus serotypes has occurred in Indonesia. This condition should be monitored continuously through the Dengue Virus Surveillance. Implementation of Dengue Virus Surveillance also conducted by BBTKL PP Surabaya. The purpose of this study was to determine the workflow, identify problems, set priority problem, find the cause of the problem, and provide the alternative solution related to problems of Dengue Virus Surveillance in BBTKL PP Surabaya. This is a operational research and the informants are officers of Dengue Virus Surveillance in BBTKL PP Surabaya. Data in this study was analyzed descriptive and presented narrative. Results showed that the workflow of Dengue Virus Surveillance in BBTKL PP Surabaya are collecting of patient’s blood and vector specimen, vector survey and collecting the supporting data, Rapid Diagnostic Test (RDT) and Polymerase Chain Reaction (PCR), processing and data analysis, and dissemination the information. The main problems of Dengue Virus Surveillance in BBTKL PP Surabaya is the low quality of the information. Tree problem analysis showed that the cause of problem that can be intervene are incomplete supporting data and data storage. Alternative solution related to problems of Dengue Virus Surveillance in BBTKL PP Surabaya is use of Epi Info.Keyword: surveillance, dengue virus, data management
Pattern of Clinical Medication Seeking for Import Malaria by Migrant Workers
Authors: Mahmudi Muhammad , Yudhastuti Ririh
Published: April 2018

Number of malaria cases in Kabupaten Trenggalek in 2014 is 89 cases, and 83 cases are import malaria from migrant workers. Import malaria is transmitted across two areas and affects the clinical medication seeking. This research wants to describe the pattern of clinical medication seeking for import malaria by migrant workers in Puskesmas Pandean working area. This was cross sectional study with descriptive quantitative approach. Research’s sample is 26 import malaria sufferers in 2013–2015 who has chosen purposively with inclusion criteria. Interview had used to get information about characteristics, place felt the symptom, first clinical medication seeking (place and time), clinical diagnosis, medication follow up, and recovery status. The result of the research shows 100% respondent is man and the age about 20-30 years old (53,8) who is working as agricultural laborers outside Java. Mostly of respondent feel the malaria symptoms in their working place (53,8%). The day seeks clinical medication at day three after symptom (34, 6%). Respondents that feel the symptom in Puskesmas Pandean working area chose Puskesmas as clinical medication place (42,3%), and hospital (19,2%) for them whose experience the malaria symptom in their working area. Puskesmas is chosen as clinical diagnosis place (69%) and only 11,5% respondent got medication follow up. Puskesmas is chosen as intermediate clinical medication place (60%) for 19,2% respondent that is not recovered well, although 20% go to Dukun. All of respondent chose the clinical medication as their prime medication. Need to make medication follow up visitation well complete.Keyword: pattern, clinical medication, import malaria, migrant worker
Development of Predictive Index for Default Treatment At Multibacillary Leprosy in District Sampang
Authors: Rukua Muhammad Syarif , Martini Santi , Notobroto Hari Basuki
Published: April 2018

Default relating to the regularity of treatment in the patients taking the drugs. If the leprosy patients taking medication irregularly, then the leprosy bacteria can become resistant or immune to Multy Drug Therapy, so the symptoms persist and even worsen. The purpose of this study was to determine the indicators and develop a predictive index formula default incidence of leprosy treatment. This type of research was a case control design. The sample size in this study was 62 respondents. The sampling technique in this study used simple random sampling technique. Data collection techniques done with interviews with the questionnaire. The results showed that a candidate indicator variables (p <0.25) is income (p value = 0.013), access to health care (p value = 0.022), the role of health workers (p value = 0.032), knowledge (p value = 0.001), and family support (p value = 0.023), perception of the disease (p value = 0.098), leprosy reactions (p value = 0.198). Variables as indicators of default treatment of leprosy patients are the role of health workers, family support, knowledge, and income. The predictive index of default treatment at multibacillary leprosy patients are (-1666+ 1451 * Revenues (low) + 1989 * Role of Health Personnel (less instrumental) + 1.338 * Knowledge (less) + 1543 * Support Family (unfavorable). This index has a 79% accuracy rate. This index is expected to be used as a measuring tool in helping health workers to screen patients with leprosy who are undergoing treatment, so early can know where the potential patients defaulting treatment.Keywords: indicators, predictive index, default of treatment, leprosy, multibacillary
Rapid Assessment of Third Round of Sub PIN Diphteria at Tambakrejo Village Jombang
Authors: Ummamah Fatikhatul
Published: April 2018

The third round of Sub PIN diphteria in Tambakrejo village has the lowest coverage and did not reach the target at age 2-36 months (61,77%) and age 3-7 years (82,39%). The aim of this study to describe more about implementation of third round of Sub PIN diphteria in November 2013. This study is descriptive research with Cross Sectional study design. Population is all of parents whose children’s ages 2 month to 15 years old when third round of Sub PIN diphteria are conducted in Kelurahan Tambakrejo. Samples on this research are 150 people were taken from two stages, the first stage is specifiying to 30 clusters (RT) and each cluster are taken 5 respondens. The variables examined in this study are immunization status, the reason not joining Sub PIN, source of information, characteristics of the respondents including age, educational level, occupation, number of children, parent’s knowledge and children’s age. The results showed that 26% of respondents did not covered by the third round of Sub PIN diphteria with the most reason is the children are not willing or crying (56,4%). If seen from  respondents whose their children did not covered by the Sub PIN can be known most of them got information (92,3%) and characterictic of respondents most of them have age above 30 years old (66,7%), high level of education from SMA (61,5%), do not work (66,7%) with the number of children that they had 2 childs or under it (61,5%),high level of knowledge (76,9%), most of children’s age is 2 months up to 36 months (43,6%) and 7 years old up to 15 years old (43,6%). Concelling anda approach personally is needed by medics to inform about the benefits of Sub PIN and the danger if did not immunization especially to a pent whose child refuse immunized.Keywords : Rapid Assessment,  SUB PIN, Diphteria
The Relationship between Knowledge, Sickness Period, and Intraocular Pressure to the Quality of Life of Glaucoma Patient
Authors: Ananda Efifta Pratama
Published: April 2018

Eyes are an important sense because it has function to collect visual information, eyes can be in emergency condition if the function of sight got threatened. Glaucoma is the second causes of blindness after cataract which is permanent or irreversible. It can decrease the quality of life’s glaucomapatient. The purpose of this study is to reveal the relationship between knowledge, sickness period and intraocular pressure to the quality of life of glaucoma patient. This study is an  analytical observation study which used sectional cross design study. The sample of this study were primary glaucoma patients and secondary glaucoma which have medical treatment in Rumah Sakit Mata Undaan Surabaya. The sample was choosen by systematic random sampling and the total number of sample are 68 peoples. The data have collected by having interview the glaucoma patients and seeing the medical records. To process the data, the writer used Chi Square analysis or Fisher Exact with 95% significance. The result of the study showed that there is a relationship between knowledge (p =0,033) and sickness period (p =0,035), while the intraocular pressure is not related to the quality of life’s of glaucoma patients in Rumah Sakit Mata Undaan Surabaya. The conclusion of this study is knowledge and sickness period have a relationship to the quality of life of glaucoma patients, while intraocular pressure is not related to the quality of life of glaucoma sufferers. The suggestion is to do early detection to people who have risk to get glaucoma and give an education about glaucoma disease to increase the quality of life of glaucoma sufferers. Keywords: The quality of life, glaucoma, knowledge, sickness period
Memahami Problematika Dua Kejahatan Transnasional: Perdagangan dan Penyelundupan Orang di China
Authors: Nizmi Yusnarida Eka
Published: April 2018

Tulisan ini memaparkan dua persoalan kejahatan kemanusiaan yang saling berkaitan yakni perdagangan dan penyelundupan orang yang terjadi di China. Ada tiga hal utama yang akan dijabarkan dalam tulisan ini, Pertama, menganalisa penyebab, dan dampak dari perdagangan dan penyelundupan orang yang dilakukan oleh jaringan Snakeheads. Kedua, artikel ini mengkaji perdagangan orang terhadap Provinsi-provinsi di China khususnya Fujian dan Yunan. Ketiga, artikel ini membahas upaya serius yang dilakukan oleh pemerintah China untuk mengatasi perdagangan dan penyelundupan orang. Penting untuk membahas topik ini karena perdagangan orang melibatkan eksploitasi yang mengerikan terhadap perempuan dan anak-anak sebagai kelompok yang sangat rentan di China. Penyelundupan dan perdagangan manusia di China mengancam keberlangsungan kehidupan perempuan dan anak sebagai kelompok yang diburu di China. Kejahatan penyelundupan dan perdagangan manusia antar negara mencerminkan bahwa banyak pemerintah yang tidak memiliki kebijakan yang efektif dan ketat terkait dengan perpindahan orang melewati batas negara termasuk pemerintah China dalam kasus ini.
Global village dan Globalisasi dalam Konteks ke-Indonesiaan
Authors: Pamungkas Cahyo
Published: April 2018

Tulisan ini memunculkan definisi global village dalam konteks Indonesia. Bagian pertama dari makalah ini menjelaskan konsep awal global village oleh McLuhan (1962) yang terkait dengan keterhubungan antarwarga dunia. Bagian kedua menerangkan respon terhadap konsep global village dan bagian bagian ketiga menjelaskan perbedaan antara global village dan globalisasi. Akhirnya, penelitian ini menggambarkan global village dan globalisasi dalam konteks Indonesia. Global village dapat didefinisikan sebagai fenomena globalisasi pada masa kini yang dapat dikenali dari akibatnya yakni melemahnya batas-batas nasional, menghilang identitas dan budaya lokal, mengancam ekonomi nasional di tengah-tengah ekspansi modal, dan meningkatnya migrasi internasional. Konsep ini mengacu pada spektrum masyarakat baru yang melampaui batas-batas geografis, ekonomi, politik dan budaya dan menekankan pada arus informasi dalam jaringan komunikasi.
Modulatory Effect of Polyphenolic Compounds from the Mangrove tree Rhizophora mangle L. Improving Non-Alcoholic Fatty Liver Disease and Insulin Resistance in High-Fat Diet Obese Mice
Authors: Mendes de Souza Mesquita Leonardo , Rabelo e Paiva Caria Cíntia , Souza Santos Paola , Cesar Ruy Caio , da Silva Lima Natalia , Kono Taketa Moreira Débora , Quintino da Rocha Claudia , Carisa Murador Daniella , Vera de Rosso Veridiana , Gambero Alessandra , Vilegas Wagner
Published: April 2018

Rhizophora mangle L. is a well-known medicinal plant found in mangroves worldwide used to treatment diabetes. This study evaluated the chemical composition of the acetonic extract from Rhizophora mangle barks (AERM), by HPLC-PDA and FIA-ESI-IT-MS/MS and the effects on high-fat diet induced obesity in mice and its mechanism of action by gene expression of inflammatory markers (Pparg, Ppara, Srebf1, Cd36, Tnf, Ccl2, Lep, Il10, Il6, Fasn, 18s). High-fat diet fed mice during 12 weeks was used as model of obesity and associated alterations. The results were very satisfactory, the extract, rich in polyphenolic compounds, flavonoids and phenolic acids, displayed intense antioxidant activity in vitro (608 µmol Trolox/g), and showed excellent activity against non-alcoholic fatty liver disease (NAFLD) and reverse insulin resistance in a model of diet-induced obesity. We can registered a modulatory effect of AERM in liver PPAR-γ mRNA expression associated to an important inhibition of CD36 mRNA expression suggesting that AERM induces the down regulation of CD36 mRNA via PPAR-gamma inhibition. These results support the traditional knowledge about the use of R. mangle for the treatment of type 2 diabetes and reveal the potential of AERM for the treatment of NAFLD and management of obesity and comorbidities.
Optimalisasi Penggunaan Daun Ubikayu sebagai Pakan Ternak Ruminansia
Authors: Handayanta Eka
Published: April 2018

Pakan merupakan faktor yang sangat penting dalam usaha pengembangan peternakan. Ternak ruminansia (sapi, kerbau, kambing dan domba) pakan utamanya adalah hijauan. Kualitas hijauan yang tinggi dalam jumlah yang cukup diperlukan untuuk mendukung produksi yang optimal.

Ketersediaan pakan hijauan dalam mendukung produksi sering mengalami kendala yakni oleh karena tidak terjaminnya kontinyuitas produksi hijauan maupun adanya zat anti nutrisi di dalam hijauan tersebut. Daun ubikayu merupakan limbah pertanian yang memiliki potensi (kuantitas dan kualitas) sebagai pakan ternak. Namun dalam penggunaannya terdapat faktor pembatas karena kandungan asam sianida (HCN)-nya.

Pengaruh (efek) negatif (toxoc) HCN dapat dikurangi dengan cara menurukan kandungan HCN dalam daun ubikayu tersebut dengan jalan mengangin-anginkan/melayukan dan atau penjemuran, atau dapat pula dilakukan dengan cara menambah senyawa atau asam amino yang mengandung sulfur mserta vitamin B12 dalam pakan/ransum.
El problema de la tyche en la literatura griega postclásica: a propósito del relato de Solón y Creso según Plutarco
Authors: Muñoz Gallarte Israel
Published: April 2018

Few years ago in a meeting organized in Paris by the IPS we dealt with Plutarch's treatment of Herodotus’ story regarding the meeting of the Athenian councilman with Croesus of Lydia in his Life of Solon. It is our aim in this occasion to focus on the suppression of two crucial elements from Herodotus’ story, to wit the alleged ‘envy of gods’ and the historian’s cyclic conception of history. Therefore, from an analysis of the reasons behind this elimination, we think that we will be able of understand the consequences for Plutarch's theory of tyche.
Parameter Estimation from Sandface Drawdown Temperature Transient Data in the Presence of a Skin Zone Near the Wellbore
Authors: Panini Filippo , Onur Mustafa
Published: April 2018

The objectives of this study are to develop a new approximate analytical solution for predicting drawdown temperature transient behavior of a fully penetrating vertical well in a radial composite reservoir system and to use it as a forward model for estimating the fluid flow and thermal parameters of the system by nonlinear regression. The analytical solution considers a radial composite reservoir model, where the inner zone may represent a skin zone and the outer zone represents an infinitely extended reservoir. The analytical solution for predicting sandface temperatures is obtained by solving the decoupled isothermal diffusivity (pressure) and temperature equations for the inner and outer zones by using the Boltzmann transformation. The convection, transient adiabatic expansion and Joule-Thomson heating effects are all considered in solving the temperature equation. The developed analytical solution is validated by using both a commercial non-isothermal numerical simulator and a semianalytical solution available in the literature for different synthetic cases. For estimating the system parameters by history matching of observed temperature and/or pressure data with the model, we use the Levenberg-Marquardt method. We investigate the impact of noise in temperature and/or pressure data on the estimated parameters by inspecting statistical measures such as confidence intervals and correlation coefficients between parameter pairs. It is observed that selecting proper initial guesses of parameter is critical for estimating reliable values of the parameters through nonlinear regression of temperature data because the parameters are more correlated in the temperature equation than in pressure equation. Hence, we provide an effective methodology based on semi-log analysis and log-log diagnostic plots of pressure and temperature data to obtain good initial guesses of parameters that will derive the nonlinear regression method to have refined optimized estimates. The results show that the rock, fluid and thermal properties of the skin zone and non-skin zone can be reliably estimated from sandface temperature transient data jointly with pressure transient data in presence of noise, recorded during constant-rate drawdown tests with our approximate solutions and effective methodology proposed for obtaining initial guesses of the parameters.
Impact of Sulphates Presence During Application of Smart Water Flooding Combined with Polymer Flooding
Authors: Tahir Muhammad , Hincapie Rafael E. , Foedisch Hendrik , Abdullah Hiwa , Ganzer Leonhard
Published: April 2018

Oil recovery using Smart Water technology (SWF) can be maximized by optimizing the composition of injected water. Brine optimization is also believed to improve Polymer Flooding (PF) performance. The present study aims to assess and define the potential impact of combining Smart Water with Polymer Flooding, based on the sulphates presence in formation/injection water and rock composition. In this work, we study the impact of sulphates (sodium sulphates) on polymer viscoelasticity and its performance in porous media, based on oil recovery and pressure response.

Brine composition is optimized after having synthetic sea water (SSW) as a base brine. Brine optimization is performed by doubling the amount of sulphates, whilst diluting (in fresh water) the SSW-brine to a tenth of its initial concentration. Thus, four brines were utilized: 1) SSW (formation water), 2) SSW but double sulphates, 3) SSW/10 and 4) Brine 2/10. The workflow included core plugs aging prior core flooding. Secondary tertiary and quaternary mode experiments were performed to evaluate the feasibility of applying both processes.

The SSW-brine optimization (a tenth of its initial concentration) resulted in a salinity of 4.2 g/L which is in good agreement with previous studies (≤5 g/L), to guarantee additional oil recovery using SWF. Polymer rheological characterization was performed over wide range of shear rates and temperatures. Sodium sulphates showed increase in polymer viscosity as compare to sodium chloride or divalent cations. Enhancement in polymer linear viscoelasticity is observed with an increase in sulphate ions concentration. Furthermore, viscosity analysis over temperature has advocated to perform the core flood experiments at 45°C. Fluids were optimized/selected using a comprehensive rheological evaluation (ηoilηpolymer=2). Optimized Smart Water with higher amount of sulphates ions has shown additional oil recovery in both secondary and tertiary mode. Moreover, polymer injection in tertiary mode after smart water injection has shown significant additional oil recovery.

This study focuses on the influence of sulphates ions on SWF and PF performance for application in sandstone reservoirs. Previous studies have mainly focused the evaluation of sulphates ions impact only in carbonate reservoirs. It is of importance to further understand/clarify the effect of sulphates for field applications of SWF and PF combined. This in turn, could lead to improve the economics of project performance, by means of incremental oil and the less polymer required.
Integrated Dynamic Modelling of the Sea Lion Field
Authors: Lopez Marmolejo Aldo , Newbould Robert , Lawton Laura , Godlewski John
Published: April 2018

The Sea Lion Field is an Early Cretaceous turbidite fan complex, located in the North Falkland Basin, 220 km north of the Falkland Islands. The reservoirs are dominated by amalgamated high density turbidites (Bouma Ta and liquefied sediment gravity flows), but also contain low density turbidites, linked debrites and interdigitated lacustrine mudstones. An integrated dynamic modelling workflow which incorporates the latest understanding of the Sea Lion Field sedimentology and reservoir heterogeneities is presented.

The workflow focuses on capturing and retaining reservoir heterogeneity throughout the reservoir modelling process. Coarse-scale heterogeneity is captured during the construction of the full-field geological (static) model and conserved in the dynamic model by using the same grid dimensions. Sedimentological features (fine-scale heterogeneity) below the grid resolution are captured in separate, 3D core-scale models. Through a process of kv/kh and relative permeability upscaling, the core-scale models are used to inform effective permeability in the full-field model.

Detailed interpretation of the available core data enables a statistical evaluation, which underpins the construction of core-scale models for the individual rock types. The resulting 3D core-scale models are representative of the reservoir and the development concept in terms of reservoir dip, lithology, petrophysical and fluid properties and well spacing. Matching the coarse model behaviour to the core-scale model forecast is an inverse problem with multiple possible solutions; therefore, assisted history matching is a valuable tool for quickly obtaining, comparing and ranking possible upscaled relative permeability functions and kv/kh ratios. The upscaled relative permeability functions output from the assisted history matching workflow correct for numerical dispersion and reproduce the waterflood behaviour observed in the core-scale model, thus capturing the influence of small-scale heterogeneities.

This integrated dynamic modelling workflow allows for the direct use of detailed geological models characterising the main heterogeneities impacting flow behaviour, while retaining the ability to investigate and capture small-scale heterogeneities below the resolution of the full-field static model, thus avoiding the cumbersome process of upscaling geological properties. Assisted history matching and optimization have been integrated into the workflow, providing a robust method to produce upscaled relative permeability functions that replicate the expected waterflood behaviour.
An Experimental Investigation of Gas Production Rates During Depressurization of Sedimentary Methane Hydrates
Authors: Almenningen Stian , Fotland Per , Fernø Martin Anders , Ersland Geir
Published: April 2018

Sedimentary methane hydrates contain a vast amount of untapped natural gas that can be produced through pressure depletion. Several field pilots have proven the concept with days to weeks of operation, but the longer-term response remains uncertain. This paper investigates parameters affecting the rate of gas recovery from methane hydrate-bearing sediments. The recovery of methane gas from hydrate dissociation through pressure depletion at constant pressure was studied at different initial hydrate saturations in cylindrical sandstone cores. Core-scale dissociation patterns were mapped with magnetic resonance imaging (MRI) and pore-scale dissociation events were visualized in a high-pressure micromodel. Key findings from the gas production rate analysis are: 1) The maximum rate of recovery is only to a small extent affected by the magnitude of the pressure reduction below the dissociation pressure. 2) The hydrate saturation directly impacts the rate of recovery, where intermediate hydrate saturations (0.30 – 0.50) give the highest initial recovery rate. These results are of interest to anyone who evaluates the production performance of sedimentary hydrate accumulations and demonstrate how important accurate saturation estimates are to predict both the initial rate of gas recovery and the ultimate recovery efficiency.
Status of Data-Driven Methods and their Applications in Oil and Gas Industry
Authors: Balaji Karthik , Rabiei Minou , Suicmez Vural , Canbaz Celal Hakan , Agharzeyva Zinyat , Tek Suleyman , Bulut Ummugul , Temizel Cenk
Published: April 2018

Data-driven methods serve as robust tools to turn data into knowledge. Historical data generally has not been used in an effective way in analyzing processes due to lack of a well-organized data, where there is a huge potential of turning terabytes of data into knowledge. With the advances and implementation of data-driven methods data-driven models have become more widely-used in analysis, predictive modeling, control and optimization of several processes. Yet, the industry overall is still skeptical on the use of data-driven methods, since they are data-based solutions rather than traditional physics-based approaches; even though physics and geology are often part of this methodology. This study comprehensively evaluates the status of data-driven methods in oil and gas industry along with the recent advances and applications.

This study outlines the development of these methods from the fundamentals, theory and applications perspective along with their historical acceptance and use in the industry. Major challenges in the process of implementation of these methods are reviewed for different areas of applications. The major advantages and drawbacks of data-driven methods over the traditional methods are discussed. Limitations and areas of opportunities are outlined. Recent advancements along with the latest applications, the associated results and value of the methods are provided.

It is observed that the successful use of data-driven methods requires strong understanding of petroleum engineering processes and the physics-based conventional methods together with a good grasp of traditional statistics, data mining, artificial intelligence and machine learning. Data-driven methods start with a data-based approach to identify the issues and their solutions. Even though data-driven methods provide great solutions on some challenging and complex processes, that are new and/or hard to define with existing conventional methods, there is still skepticism in the industry on the use of these methods. This is strongly tied to the delicacy and sensitive nature of the processes and on the usage of the data. Organization and refinement of the data turn out to be important components of an efficient data-driven process.

Data-driven methods offer great advantages in the industry over that of conventional methods under certain conditions. However, the image of these methods for most of the industry professionals is still fuzzy. This study serves to bridge the gap between successful implementation and more widely use and acceptance of data-driven methods, and the fuzziness and reservations on the understanding of these methods in the industry. Significant components of these methods along with clarification of definitions, theory, application and concerns are also outlined in this study.
Harrier Development: Successful Implementation of the World's First Offshore Multilateral Installation with Staged Acid Fracturing Performed on Both Laterals
Authors: Scott-Rampersad Ria , Norris Mark , Carval Rafael Guedes , Airnes Jamie , Bramald James , Oberhofer Rob
Published: April 2018

With a suppressed hydrocarbon sector over the past few years, operators, service providers and ancillary companies alike have been strongly challenged to collaborate, where feasible, on field development solutions which offer greater economies of scale and efficiency by reducing operational time and cost. This paper details the evolution of the Harrier field development plan (FDP) in the context of innovation within completion and stimulation treatment design which has successfully created value for this North Sea gas operator.

Originally, the project plan comprised of two development wells, each accessing separate chalk gas reservoirs - Ekofisk and Tor which were approved by the UK Oil and Gas Authority in 2012 under the Stella and Harrier FDP, with an estimated development cost of USD 250 million. During the conceptual phase, the project economics were not attractive even in a high oil price environment. Services providers were then invited to provide alternative solutions to significantly enhance the investment appeal of this opportunity with the aim of reducing capital and operating expenditure while enhancing both field recovery and accelerated production. One such provider was successful with the proposition of a revolutionary contraction of the FDP with a unique design concept of a single well development terminating in a dual lateral with each leg targeting a separate reservoir in which fourteen acid stimulation stages per leg were planned to greatly enhance productivity. After several months of intensive collaboration, the optimized well design was completed and the project was sanctioned with field development cost reduced by a full 50%.

The paper provides an overview of the stimulation design, based on the reservoir challenges encountered and the progression of the completion design explored, into its final fit for purpose realisation. Results in relation to achievement of well objectives, service delivery, change management during the execution phase and most significantly overall well performance are also provided.

The objective of this paper is not only to demonstrate the value created to the field operator, but also to illustrate how planning and developing a unique solution was strongly influenced by a cost sensitive environment for efficiencies gained, with regards to risk management and mitigation, along with contingency planning. Furthermore, through a multi-segment integrated approach experience, numerous lessons learnt and best practices were harnessed for use when venturing on similar projects championing technical innovation under economic and resource constraints.
Application of Bespoke Well Completion Architecture and Integrated Surveillance in the Development and Production of a High Saline Gas Field - UK North Sea
Authors: Otaru Gabriel , Haider Syed , Nilsen Anna
Published: April 2018

The development and production of some oil and gas fields is that it sometimes brings fluid chemistry challenges. These chemistry challenges exhibit themselves in flow assurance issues which if not managed well, can lead to loss of productivity and value. Building an engineering solution to manage these risks enhances mitigation. One other key activity in optimizing and achieving value in oil and gas development is integrated surveillance and reviews cutting across various disciplines.

Neptune E & P UK Ltd has developed and brought to production the Cygnus field. It is one of the biggest gas field developments in the UK North Sea in recent years. The formation water is very saline with total dissolved solids of approximately 320,000 mg/l2. The major risk identified with the Cygnus development was halite deposition as evidenced in analogue fields developed and produced in the Southern North Sea (SNS) area by other operators. The well architectures in these fields are simple and treatment for halite deposition is carried out by dumping fresh water manually from surface. However experience from these operators, indicates that this approach was not very efficient. This has resulted in a loss of productivity, and early abandonment of wells, with associated stranded reserves.

The Cygnus Field development adopted a combination of bespoke completion architecture, an integrated approach to surveillance and review of data streaming in from the wells. Details of methods employed include the ability to continuously inject deoxygenated fresh water into the wells to provide online water washes with the wells flowing. Continuous thermal data acquisition from Distributed Temperature Sensing (DTS) fibre permanently installed across the length of the well. Pressure and temperature data measurement from permanent down-hole gauges. Surface measurement of rate, fluid fractions, salinity and pressure / temperature provided by multiphase flow meters.

The integrated surveillance and review process uses data acquired from the well instrumentation. This is normally carried out as follows: Data set preparation and validationProduction Data AnalysisShort and Long-term production strategy

This strategy has allowed the operator to use the continuous data stream for well and reservoir analysis which has helped in optimizing production yielding high operational efficiency and availability.
Multi-Disciplinary Approach to Developing Challenging Heavy Oilfields with Basal Aquifers
Authors: Law Stuart , McDonald Andrew , Castillo Edgar , Mackay Eric , Fellows Susan
Published: April 2018

In the United Kingdom Continental Shelf (UKCS), a significant heavy oil prize of 9 billion barrels has been previously identified, but not fully developed. In the shallow unconsolidated Eocene reservoirs of Quads3 and 9, just under 3 billion barrels lie in the discovered, but undeveloped fields, of Bentley and Bressay. Discovered in the 1970s, they remain undeveloped due to the various technology challenges associated with heavy oil offshore and the presence of a basal aquifer. The Eocene reservoirs represent significant challenges to recovery due to the unconsolidated nature of the hydrocarbon bearing layers. The traditional view has been that such a nature represents a risk to successful recovery due to sand mobility; reservoir and near wellbore compaction; wormhole formation; and injectivity issues.

We propose improving the ultimate oil recovery by a combination of aquifer water production and compaction drive. By interpreting public domain data from well logs, the range of geomechanical properties of Eocene sands have been determined. A novel approach to producing the heavy oil unconsolidated reservoirs of the UKCS is proposed by producing the aquifer via dedicated water producers situated close to the oil-water contact. The location was determined by sensitivity analysis of water producer location and production rates. By locating water producers at the OWC with a production rate of 20,000 bbls/day of fluids, the incremental recovery at the end of simulation is increased by 4.1% OOIP of the total modelrelative to the ‘no aquifer production’, casesuggesting a significant increase in recovery can be achieved by producing the aquifer. A rate of 30,000 bbld/day located at the OWC was found to increase incremental recovery by 5.8 %OOIP relative to the ‘no aquifer case’. In all cases, as the reservoir fluid pressure is reduced, oil recovery increases via compaction and reduced water influx into the oil leg. This reduced pressure leads to a higher tendency towards reservoir compaction which is expressed as a change in mean effective stress and porosity reduction.
Controlling Parameters for Shale Gas Production Into a Well-Induced Fracture: A Fracture-Matrix Modelling Approach
Authors: Berawala Dhruvit Satishchandra , Andersen Pål Østebø , Ursin Jann Rune
Published: April 2018

The purpose of this paper is to investigate the main controlling factors of shale gas production in the context where well-induced fractures, extending from the well perforations, improve reservoir conductivity and performance. A mathematical 1D+1D model is presented which involves a high-permeable fracture extending from a well perforation, through symmetrically surrounding shale matrix with low permeability. Gas in the matrix occurs in the form of adsorbed material attached to kerogen (modeled by a Langmuir isotherm) and as free gas in the nano-pores. The pressure gradient towards the fracture and well perforation causes the free gas to flow. With pressure depletion, gas desorbs out of the kerogen into the pore space and then flows to the fracture. When the pressure has stabilized, desorption and production stop.

The production of shale gas and mass distributions indicate the efficiency of species transfer between fracture and matrix. It is shown that the behavior can be scaled and described according to the magnitude of two characteristic dimensionless numbers: the ratio of diffusion time scales in shale and fracture α, and the pore volume ratio between the shale and fracture domains β. Properties of fracture and matrix are varied systematically to understand the role of the fracture matrix interaction during production. Further, the role of fracture geometry (varying width) is investigated. Input parameters from experimental and field data in the literature are applied.

The product αβ expresses how much time it takes to diffuse the gas in place through the fracture to the well compared to the time it takes to diffuse that gas from the matrix to the fracture. For αβ ≪ 1 the residence time in the fracture is of negligible importance and fracture properties such as shape, width and permeability can be ignored. However, if αβ ≈ 1 the residence time in the fracture becomes important and variations in all those properties have significant effects on the solution.

The model allows intuitive interpretation of the complex shale gas production system. Furthermore, the current model creates a base which can easily incorporate non-linear flow mechanisms and geo-mechanical effects that are not readily found in standard commercial software, and further be extended to field scale application.
Oil Recovery Analyses and Formation Water Investigations for High Salinity-Low Salinity Water Flooding in Sandstone Reservoirs
Authors: Al-Saedi Hasan , Williams Ariel , Flori Ralph , Brady Patrick , Al-Jaberi Soura
Published: April 2018

Recently, we investigated the effect of Ca2+ in the formation water and its potential on low salinity (LS) water flooding (Al-Saedi et al. 2018). In this paper, we pursue to quantify the influence of formation water containing Ca2+ and Mg2+ on LS EOR. Berean sandstone cores were sequentially flooded with high salinity HS water and LS water at 90°C. During injecting brines, samples of the effluent were analyzed for pH. Oil recovery experiments with a double Ca2+ and Mg2+ concentration showed a lower LS water effect, meaning that the cores became more water-wet; however, the LS water effect was much greater when the amount of Ca2+ and Mg2+ in the HS water was decreased by half.

The results of this work isolate and relate oil recovery with the most effective factors that control LS water chemical mechanisms.
Reconstruction of 3D Porous Media Using Multiple-Point Statistics Based on a 2D Training Image
Authors: Wu Yuqi , Lin Chengyan , Ren Lihua , Tian Weichao , Wang Yang , Zhang Yimin
Published: April 2018

Macroscopic transport properties of porous media essentially rely on the geometry and topology of their pore space. The premise of predicting these transport properties is to construct an accurate 3D pore space. To date the methods of modeling porous media are divided into two main groups, direct measurements by some equipment and stochastic statistical methods. Direct measurements of pore structure can be acquired with current equipment such as X-ray computed tomography and laser scanning confocal microscopy, but the unavailability of the equipment and the high cost of the measurement make their widespread application impossible. Many stochastic statistical methods, such as truncated Gaussian random field and simulated annealing methods, reconstruct 3D porous media based on some 2D thin sections by means of lower-order statistical functions. However these functions cannot reproduce the long-range connectivity of pore structure. Therefore, this paper will present a stochastic technique of reconstructing 3D pore space using multiple-point statistics with the purpose of solving the proposed problems. The single normal equation simulation algorithm (SNESIM), one of the most common methods for discrete variable simulation in multiple-point statistics, is the main tool to reproduce the long-range feature of pore space. To test the method, Berea sandstone was used as a sample. In the simulation process, a 2D thin section was taken as the training image for providing patterns of pore structure and some pixels were extracted from it as the conditioning data. The models were reconstructed using the SNESIM algorithm that serves as the simulation engine. In order to test the accuracy of these reconstructed models, pore geometry and topology and transport properties of the reconstructed models were compared with those of the real model obtained by X-ray computed tomography scanning. The comparison result shows that the reconstructed models are good agreement with the real model obtained by X-ray computed tomography scanning in the two-point correlation function, the pore space features and single- and two-phase flow permeabilities, which verifies that the long-range connectivity of pore space can be reproduced by this method. Comparing with other stochastic methods, a more accurate stochastic technique of reconstructing 3D porous media is put forward when only some 2D thin sections are available.
Viscous Oil Recovery by Polymer Injection; Impact of In-Situ Polymer Rheology on Water Front Stabilization
Authors: Vik Bartek , Kedir Abduljelil , Kippe Vegard , Sandengen Kristian , Skauge Tormod , Solbakken Jonas , Zhu Dingwei
Published: April 2018

Polymer injection for viscous oil displacement has proven effective and gained interest in the recent years. The two general types of EOR polymers available for field applications, synthetic and biological, display different rheological properties during flow in porous media. In this paper, the impact of rheology on viscous oil displacement efficiency and front stability is investigated in laboratory flow experiments monitored by X-ray.

Displacement experiments of crude oil (~500cP) were performed on large Bentheimer rock slab samples (30×30cm) by secondary injection of viscous solutions with different rheological properties.

Specifically, stabilization of the aqueous front by Newtonian (glycerol and shear degraded HPAM) relative to shear thinning (Xanthan) and shear thickening (HPAM) fluids was investigated.

An X-ray scanner monitored the displacement processes, providing 2D information about fluid saturations and distributions. The experiments followed near identical procedures and conditions in terms of rock properties, fluxes, pressure gradients, oil viscosity and wettability.

Secondary mode injections of HPAM, shear-degraded HPAM, xanthan and glycerol solutions showed significant differences in displacement stability and recovery efficiency. It should be noted that concentrations of the chemicals were adjusted to yield comparable viscosity at a typical average flood velocity and shear rate.

The viscoelastic HPAM injection provided the most stable and efficient displacement of the viscous crude oil. However, when the viscoelastic shear-thickening properties were reduced by pre-shearing the polymer, the displacement was more unstable and comparable to the behavior of the Newtonian glycerol solution.

Contrary to the synthetic HPAM, xanthan exhibits shear thinning behavior in porous media. Displacement by xanthan solution showed pronounced viscous fingering with a correspondingly early water breakthrough.

These findings show that at adverse mobility ratio, rheological properties in terms of flux dependent viscosity lead to significant differences in stabilization of displacement fronts. Different effective viscosities should arise from the flux contrasts in an unstable front.

The observed favorable "viscoelastic effect", i.e. highest efficiency for the viscoelastic HPAM solution, is not linked to reduction in the local Sor. We rather propose that it stems from increased effective fluid viscosity, i.e. shear thickening, in the high flux paths.

This study demonstrates that rheological properties, i.e. shear thinning, shear thickening and Newtonian behavior largely impact front stability at adverse mobility ratio in laboratory scale experiments. Shear thickening fluids were shown to stabilize fronts more effectively than the other fluids. X-ray visualization provides an understanding of oil recovery at these conditions revealing information not obtained by pressure or production data.
Pore-to-Core EOR Upscaling for CO2-Foam for CCUS
Authors: Rognmo Arthur Uno , Fredriksen Sunniva Brudvik , Alcorn Zachary Paul , Sharma Mohan , Føyen Tore , Eide Øyvind , Graue Arne , Fernø Martin
Published: April 2018

An ongoing CO2-foam upscaling research project aims to advance CO2-foam technology that accelerate and increase oil recovery, with reduced operational costs and carbon footprint during CO2 EOR. Laboratory CO2-foam behavior will be upscaled to pilot scale in two onshore carbonate and sandstone reservoirs in Texas, USA. Important CO2-foam properties such as local foam generation, bubble texture, apparent viscosity and shear-thinning behavior with a nonionic surfactant were evaluated using Pore-to-Core upscaling to develop accurate numerical tools for field pilot prediction of increased sweep efficiency and CO2 utilization. On pore-scale, silicon-wafer micromodels showed in-situ foam generation and stable liquid films over time during static conditions. Intra-pore foam bubbles corroborated apparent foam viscosities measured at core-scale. CO2-foam apparent viscosity was measured at different rates (foam rate scans) and different gas fractions (foam quality scans) at core-scale. The highest mobility reduction (foam apparent viscosity) was observed between 0.60-0.70 gas fraction. The maximum foam apparent viscosity was 44.3 (±0.5) mPas, 600 times higher than that of pure CO2. The maximum apparent viscosity for the baseline (reference case, without surfactant) was 1.7 (±0.6) mPas, measured at identical conditions. CO2-foam showed shear-thinning behavior with approximately 50% reduction in apparent viscosity when the superficial velocity was increased from 1 ft/day to 8 ft/day.