bluuebunny/crossref_metadata_2025 huggingface dataset:
Pelaksanaan Program Millennium Challenge Account (MCA) dan Kepentingan Amerika Serikat di Indonesia
Authors: Virgianita Asra
Published: April 2018

Kajian ini membahas mengenai program hibah Millennium ChallengeAccount (MCA) di Indonesia yang merupakan salah satu proyek bantuan luarnegeri Amerika Serikat (AS). Para ahli berpendapat bahwa pemberianbantuan luar negeri selalu terkait dengan motif negara donor. Studi inimenginvestigasi motif AS dalam pemberian hibah MCA ke Indonesia.Ditemukan bahwa MCA dirumuskan untuk motif politik dan ekonomi. Motifpolitik terkait dengan upaya AS untuk menunjukkan komitmen dalam isupelestarian lingkungan global. Motif ekonomi terkait dengan upaya-upayaAS untuk melindungi perusahaan minyak dan gas AS di Indonesia terhadaptuntutan untuk masalah lingkungan dan sosial, perluasan pasar AS untukproduk kesehatan dan farmasi, dan pembentukan iklim yang kondusif bagiperusahaan AS
Indonesian Labour Migration: Identifying the Women
Authors: Yazid Sylvia
Published: April 2018

This paper is concerned with two main issues, Indonesian women workingabroad in the informal sector, mostly as domestic workers and the potentialsof other women stakeholders in addressing issues faced by women migrantworkers. This paper is written based on the assumption that an identificationof potential women at various levels and institutions may contribute to thesearch for solutions for the problems faced by the women migrant workersand that women should be seen as active actors that may contribute to theproblem solving. The identification in this paper has been able to identify theexistence of a number of prominent women migrant workers advocates, arguefor their existence in various parts within the labour migration system toguarantee a protected migration for women labour, and suggest for thewidening of the scope and activism of these women migrant workersadvocates, in line with their movements across institutions.
Foreign Policy and National Interest: Realism and Its Critiques
Authors: Manan Munafrizal
Published: April 2018

Realism stated that conflict or even war among countries are acceptable in order to achieve national interest. Such a view has become the mainstream in international relations (IR) both theoretically and practically. But it does not mean that realist views are the best approach to discuss foreign policy and national interest. Liberalism and global humanism can be used as alternative approaches to discuss it. From the perspective of liberalism and global humanism, foreign policy is not only reflecting national interest, but also dealing with human and global interest. By focussing on the issues of economic globalization, democracy, human rights, and environment, the approaches of liberalism and global humanism show that these issues have now become a part of foreign policy and national interest of countries. It means that if it comes to human and global interests, then countries choose to cooperate globally rather than to involve in conflict or war.
Quo Vadis Melanesian Spearhead Group?
Authors: Wardhani Baiq LSW
Published: April 2018

Menguatnya sentimen identitas di dalam Melanesian Spearhead Group (MSG) bersamaan dengan kecenderungan melemahnya kapabilitas kemandirian untuk melakukan tata kelola domestik merupakan salah satu faktor yang menyebabkan berubahnya dinamika di Pasifik Selatan. Salah satunya ditandai dengan menguatnya kekhawatiran bahwa negara-negara di dalam kelompok ini semakin sulit melepaskan diri dari ketergantungan terhadap bantuan luar negeri. Menguatnya sentimen identitas secara empiris dapat diamati dari pergolakan di dalam organisasi tersebut, yang menunjukkan bahwa para anggotanya semakin tidak khawatir pada perbedaan pendapat di antara mereka. Sementara itu lemahnya kapabilitas mengelola secara mandiri persoalan domestik ditunjukkan dengan meningkatnya bantuan finansial dari negara donor. Padahal pada saat yang bersamaan krisis di negara donor dan relatif menurunnya urgensi Pasifik Selatan dalam geopolitik negara-negara donor dapat membawa organisasi regional ini dalam posisi limbo. Alternatif jalan keluar telah diambil, namun menimbulkan pertanyaan, mau dibawa ke manakah MSG?
Sengketa Laut Tiongkok Selatan: Ancaman Bagi Komunitas Keamanan ASEAN?
Authors: Haryanto Agus , Darmawan Arief Bakhtiar
Published: April 2018

Perbedaan sikap diantara negara ASEAN seringkali disebut sebagai titik kegagalan pembentukan Komunitas Keamanan. Tulisan ini menelaah lebih jauh mengenai komponen pembentuk Komunitas Keamanan dalam konteks sengketa LTS. Menggunakan argument Karl Deutch yang menyatakan ada tiga hal yang perlu diperhatikan dalam membentuk masyarakat keamanan, yaitu (1) para pembuat kebijakan dan masyarakat berhenti merenungkan kemungkinan perang (2) negara berhenti mengalokasikan sumber daya untuk membangun kemampuan militer yang ditujukan kepada negara lain dan (3) ada penerimaan dan kepatuhan yang ketat terhadap aturan-aturan dan perjanjian tertentu bila tujuan kolektif unit-unit tidak selaras. Tulisan ini berargumen bahwa ketiga komponen pembentuk Komunitas Keamanan terganggu ketika ASEAN menghadapi sengketa LTS. Pertama, mengganggu upaya penyebaran norma-norma ASEAN. Kedua, mengganggu upaya mekanisme pencegahan konflik. Ketiga, menghambat ikatan kepercayaan diantara anggota ASEAN.
Diplomasi Soft Power Indonesia melalui Atase Pendidikan dan Kebudayaan
Authors: Soesilowati Sartika
Published: April 2018

Studi ini membahas implementasi diplomasi Soft Power Indonesia melalui pertukaran dan pengembangan pendidikan dan kebudayaan di luar negeri. Bagaimana sebenarnya strategi dan karakter diplomasi ini? Sampai seberapa jauh diplomasi pendidikan memperkuat tujuan dan kepentingan nasional? Apa saja upaya, tantangan dan kesempatan dalam mengimplementasikan tipe diplo-masi ini? Studi ini menguatkan argumen bahwa ada hubungan secara langsung atau tidak langsung antara diplomasi pendidikan dan kepentingan nasional. Disamping beberapa beberapa capaian, masih ada beberapa kekurangan, dan kendala yang menghambat untuk dapat memaksimalkan hasil dari upaya pertukaran pendidikan internasional ini. Artikel ini juga berargumen bahwa diplomasi Soft Power memperkuat signifikansi ‘new diplomacy’ atau ‘neo diplomacy’. Bentuk diplomasi ini melibatkan berbagai aktor sehingga bersifat inklusif dalam proses diplomasi saat ini dibutuhkan. Untuk menjelaskan secara lebih terperinci dari fenomena ini maka juga akan diterangkan dengan studi kasus atase Pendidikan dan Kebudayaan Indonesia di Filipina.
Possibilities of Inclusive Education for Students With Special Educational Needs
Authors: Kožárová Jana
Published: April 2018

There are approximately 800 million young children worldwide affected by biological, environmental and psychosocial conditions that can limit their cognitive development. In Europe, recent estimates place the number of children with special educational needs (SEN) at 15 million. Conservative estimates state that dyslexia, a learning disability that impedes a person’s ability to read, affects approximately 6 percent of Europe’s population, whilst the prevalence of autistic spectrum disorders is also estimated to be higher than previously thought. Children with SEN frequently leave school with few qualifications and are much more likely to become unemployed or economically inactive. Children with SEN are children first and have much in common with other children of the same age. There are many aspects to a child’s development that make up the whole child, including-personality, the ability to communicate (verbal and non-verbal), resilience and strength, the ability to appreciate and enjoy life and the desire to learn. Each child has individual strengths, personality and experiences so particular disabilities will impact differently on individual children. A child’s special educational need should not define the whole child. Presented paper briefly introduces different categories of special educational needs and subsequently describies inclusive education as a concept potentially successful for their academic and vocational performance.
Porous (Swiss-Cheese) Graphite
Authors: Abrahamson Joseph P. , Rajagopalan Ramakrishnan , Vander Wal Randy L.
Published: April 2018

Porous graphite was prepared without the use of template by rapidly heating the carbonization products from mixtures of anthracene, flourene, and pyrene with a CO2 laser. Rapid CO2 laser heating at a rate of 1.8 × 10 6 °C/s vaporizes out the fluorene-pyrene derived pitch while annealing the anthracene coke. The resulting structure is that of graphite with 100 nm spherical pores. The graphitizablity of the porous material is the same as pure anthracene coke. Transmission electron microscopy revealed that the interface between graphitic layers and the pore walls are unimpeded. Traditional furnace annealing does not result in the porous structure as the heating rates are too slow to vaporize out the pitch, thereby illustrating the advantage of fast thermal processing. The resultant porous graphite was prelithiated and used as an anode in lithium ion capacitors. The porous graphite when lithiated had a specific capacity of 200 mAh/g at 100 mA/g. The assembled lithium ion capacitor demonstrated an energy density as high as 75 Wh/kg when cycled between 2.2 V to 4.2 V.
Comparative Pathogenesis of Asian and African-Lineage Zika Virus in Indian Rhesus Macaque’s and Development of a Non-Human Primate Model Suitable for the Evaluation of New Drugs and Vaccines
Authors: Rayner Jonathan O. , Kalkeri Raj , Goebel Scott , Cai Zhaohui , Green Brian , Lin Shuling , Snyder Beth , Hagelin Kimberly , Walters Kevin B. , Koide Fusataka
Published: April 2018

The establishment of a well characterized non-human primate model of Zika virus (ZIKV) infection is critical for the development of medical interventions. In this study, challenging Indian rhesus macaques (IRMs) with ZIKV strains of the Asian lineage resulted in dose dependent peak viral loads between days 2 and 5 post infection; and a robust immune response which protected the animals from homologous and heterologous re-challenge. In contrast, viremia in IRMs challenged with an African lineage strain was below the assays lower limit of quantitation and the immune response was insufficient to protect from re-challenge. These results corroborate previous observations but are contrary to reports using other African strains obviating the need for additional studies to elucidate the variables contributing to the disparities. Nonetheless, the utility of an Asian lineage ZIKV IRM model for countermeasures development was verified by vaccinating animals with a formalin inactivated reference vaccine and demonstrating sterilizing immunity against a subsequent subcutaneous challenge.
Enhancing dental electives through participatory research
Authors: Rogerson Niall , McKenna Kate , Robinson Louise , Wemyss Callum , Bagg Jeremy , Bovill Catherine
Published: April 2018

Completion of an elective project at the University of Glasgow Dental School is a progression requirement that entails a period of self-directed and enquiry-led learning. This study sought to uncover students’ expectations and perspectives of their elective experience as there is a scarcity of supporting literature to determine if this activity has significant educational value. This qualitative study utilised a participatory research methodology,ensuring that students were at the centre of the enquiry process. Three student co-researchers analysed data collected from their peers, using a questionnaire and a focus group meeting. The findings support maintaining autonomous, enquiry-led, independent learning-focused electives and also highlight aspects of the elective which students particularly valued. This has allowed a deeper understanding of students’ perceptions of, and motivations for, particular elective projects, enabling the elective programme to respond to changing environments in education and global health. The outcomes of this study have informed the redesign of the dental elective study programme and the associated quality assurance process.
Mystery Shopper Lecture Feedback Programme – a collaborative project between staff and students at a graduate entry medical school
Authors: Maxfield Hannah , Flemming John , Mills Logan , Owen Katherine
Published: April 2018

The pilot study described is an innovative model which ensures that lecturers receive relevant and tailored feedback from students in order to improve their delivery of lectures, ultimately improving student education.The current method of lecture feedback at Warwick Medical School asks students to comment on a whole term’s worth of lectures at once – consequently feedback is often non-specific and unconstructive.This project has been rolled out by a collaborative team of four medical students and one Faculty member. The project team designed a training event to instruct 10-15 students from each year group to deliver constructive and useful feedback to lecturers. The project team designed the online feedback form, which is completed by the trained students after observing a lecture. Students sign up to review lectures via a digital platform managed by the project team. Once the feedback form is submitted, it is quality-control-assessed by a Faculty member before being sent anonymously to the lecturer.This project allows medical students to provide lecturers with meaningful information about what they did well and how they can improve. Initial feedback from lecturers has been positive; they have valued the constructive criticism and the suggestions they have been given for improving future lectures.
Who sets the agenda on student engagement?
Authors: McIntosh Emily , Cross Duncan
Published: April 2018

The rise in UK university fees has prompted significant investment in the student experience, with increased emphasis on an agenda that promotes student engagement and partnership. Government papers, both white and green, have set out a policymaking agenda and have led to a reorganisation of the UK higher education funding structures, with the dissolution of long-standing funding bodies into the Office for Students. This enshrines chapter B6 of the QAA UK quality code for higher education with regard to student engagement and would appear to be a positive move forward. However, the Office for Students has limited student representation and this raises the question: ‘Who sets this agenda and who are the stakeholders?’ This opinion piece seeks both to highlight the necessity for a joint agenda-setting approach and to engage the community in developing a joint agenda on student engagement and partnership.
A robust methodology for tracking and evaluating student engagement
Authors: Lees Dawn , Pocklington Amanda , Hibberd Jake , Allington Simon
Published: April 2018

Digital solutions for tracking and evaluating student engagementare limited. This paper reviews the implementation of a digital solution used to transform two Student Engagement schemes at the University of Exeter: ‘Peer Learning’ and ‘Students as Change Agents’.By means of the workflow function in CareerHub, an online career management system, workflows have been created to enable the management, in one efficient platform, of student recruitment, training, tracking and learner reflection. Since all student engagement records and knowledge of interactions are in one place, asignificant reduction in administration and enhanced opportunities for effective evaluation have been achieved.Previously, student skills development and reflection to enhance student employability had not been a significant feature of either Peer Learning or Students as Change Agents. With the automated workflow, students can now access the right guidance at the right time, thereby making more effective step-by-step progress through either scheme. Students are also able to track their own progress and manage their involvement with the projects more effectively. The workflows have created clear audit trails so that these activities are verifiable and easily articulate with student Exeter Award profiles and the Higher Education Achievement Report (HEAR).
Student/staff ‘Collaborative Event Ethnography’ at the Antiques Roadshow
Authors: Weston Gavin Michael , Djohari Natalie
Published: April 2018

This case study reports and reflects upon a project using Collaborative Event Ethnography (CEE) as, simultaneously, a research and teaching method. Through training workshops and a day of interviews and participant observation at the Antiques Roadshow at Ightham Mote in Kent, staff and students worked together on a project that clearly demonstrated the scope of the CEE method for producing robust academic data while also challenging presumptions that ethnography is a necessarily lone pursuit.
Students’ perspective on participation in a co-design process of learning scenarios
Authors: Garcia Iolanda , Noguera Ingrid , Cortada-Pujol Meritxell
Published: April 2018

The adoption of co-design processes involving teachers and students is considered a helpful strategy for developing learner-centred scenarios. This research includes students in the co-design of learning scenarios that are inquiry-based (IBL) and enhanced by technology (TEL). In this paper, students’ contribution to the co-design process is analysed, as well as the impact it had on them. The data was collected before and after the project by means of interviews and a questionnaire applied to eleven students from two universities (one blended and one virtual). The results show that the students’ main contribution has a relationship with methodological and organisational aspects, and that the main benefit they perceive is gaining a better understanding of the teacher’s role and the complexity of designing learning scenarios. The study also shows some of the drawbacks and challenges of a co-design process.
AS EMPRESAS SOCIAIS DE INSERÇÃO NA PROMOÇÃO DO EMPREGO E INCLUSÃO SOCIAL A PARTIR DE ESTUDOS DE CASO EUROPEUS
Authors: Quintão Carlota , Martinho Ana Luísa , Gomes Mafalda
Published: April 2018

As WISE (work integration social enterprise) - empresas sociais de inserção pelo trabalho - são organizações economicamente produtivas, com missão social e propósito de inserção profissional de públicos em situação de vulnerabilidade à pobreza e exclusão social. No contexto nacional português, marcado pela extinção da legislação da medida de política ativa de emprego e por ausência de política eficaz de integração destes públicos, a análise de modelos europeus, distintos e complementares, é essencial para equacionar a intervenção e impacte das WISES para o emprego e inclusão social. Com base em 10 estudos de casos de cinco países europeus (Áustria, Bélgica, Itália, Portugal e Reino Unido), analisamos cada WISE enquanto exemplo de inovação social. A amostra intencional de dois estudos de caso por país identificou três modelos: i) modelo de transição para o mercado de trabalho regular; ii) modelo de emprego permanente; iii) modelo cooperativo de autoemprego.
Impact of Composition on Natural Gas Desorption from Kerogen
Authors: Pang Wei , Ding Shidong , Zhang Thongyi , Xia Wenwu , Akkutlu I. Yucel
Published: April 2018

Shale gas reservoirs hold adsorbed gas in kerogen. Laboratory techniques have been developed to measure the gas amount in samples. However, adsorbed gas recovery is an unsettled issue. Complexity is mainly due to adsorbed phase having an unknown composition and density, and desorbing in a selective fashion. Kerogen nanopores bring in added complexity to the analysis due to confinement effects. Our objective is to predict gas composition in kerogen pores and measure desorption limit during pressure depletion.

A new molecular simulation method is developed to predict in-situ composition of natural gas in model kerogen pores using composition of produced fluid from a Chinese shale gas well. In essence, the method re-distributes the fluid composition back into kerogen pores at initial reservoir conditions. Then one-by-one the pores are blown down in small pressure steps while the compositional variation in the pores is monitored. The recovery is measured by comparing the residual hydrocarbon molecules at different pressure steps during the blow down. Density, viscosity, mean free path of the fluids in model kerogen pores are computed using the trajectories of the adsorbed and free molecules.

At initial reservoir conditions we found that the gas mixture in kerogen nanopores becomes heavier and more viscous as the pore size becomes smaller. These compositional effects become significantly more amplified during the pressure depletion. Consequently, we observe that the kerogen pores release only the lighter end of the initial natural gas mixture in the pores, not allowing desorption of the heavier mixtures in smaller pores. The predicted Knudsen number values indicate that the compositional evolution in kerogen with pore size and pressure does not allow flow regime change. For the Chinese shale gas well fluid composition, we predict that the pores smaller than 5 nm has limited gas recovery and the transport in the larger pores stays in the slip flow regime.

The paper presents results of recovery from kerogen using molecular simulation of fluids in nanopores. The results bring in new insights into our understanding of the natural gas production limits from kerogen. The results indicate that methane adsorption isotherms do not represent the true nature of multi-component gas desorption from shale samples.
Visualization of Heavy Oil Mobilization by Associative Polymer
Authors: Skauge Tormod , Djurhuus Ketil , Reichenbach-Klinke Roland
Published: April 2018

Polymer flooding has increasingly been considered for heavy oil recovery applications. This has been encouraged by positive results from field applications at e.g. Pelican Lake and Tamaredjo and lab experiments showing that highly efficient recovery can be obtained at mobility ratios far from unity. Improved understanding of the mobilization process will increase process efficiency. Here we have used x-ray visualization to study sweep efficiency by an associative polymer at adverse mobility ratio in 2D flow.

The x-ray scanner provides visual information on the development of fingers and saturation changes during the flooding process. Sweep efficiency was evaluated in two dimensional flow using a 30x30x2 cm slab of Bentheimer outcrop sandstone. A 540 cP crude oil was first displaced by water, then by 1000 ppm of a PAM-based associative polymer in a low salinity brine. Associative polymers have a potential for intermediate heavy oil/heavy oil applications due to favorable salt and shear tolerance, thermo-thickening properties and high resistance factors (RF) obtained in porous media due to hydrophobic interactions.

Oil displacement by water at adverse mobility ratio is characterized by frontal instability and fingering of the water phase through the oil phase, leading to early water breakthrough and poor sweep efficiency. The details of this process is not revealed in typical core floods as pressure and production data can be fitted to a multitude of recovery scenarios for an unstable displacement. The x-ray visualization showed that the water flood was highly unstable with numerous thin fingers forming. As expected, an early water breakthrough was observed at about 0.07 PV injected. After water breakthrough additional oil recovery was primarily inefficient sweep between existing fingers. Polymer injection initiated at a stable, high water cut (97 - 98 %) was highly efficient, recovering 21 % OOIP over 0.7 PV injected. Production data showed a strong reduction in water cut suggesting formation of an oil bank. Saturation images confirmed this, and additionally revealed that the oil bank was formed by a combined polymer sweep between fingers and by expansion of established fingers in the first 2/3 of the slab, leading to accumulation toward the production well. However, the polymer flood was unstable, with no clear polymer bank formed in contrast to typical 2D polymer floods at lower mobility ratio.

This is to our knowledge the first 2D flow experiment of oil mobilization by associative polymers. It shows that the polymer is highly efficient in accelerating the production in a tertiary flood where water is inefficiently flowing predominantly in an established water finger pattern. Combining visualization of 2D flow with pressure and production data leads to better insight into the mechanism of oil mobilization by associating polymer.
Experimetal Study and Numerical Modelling of the Effect of Foaming Agent Properties on Foam Flooding in Porous Media in Absence of Oleic Phase
Authors: Hosseini-Nasab Seyed Mojtaba , Simjoo Mohammad
Published: April 2018

This paper presents an investigation on the effect of foaming agents perpropeties in tetms of surfactant concentration, interfacial tension (IFT) and foam strength during foam flooding in porous media in the absence of oleic phase. The experiments consisted of the co-injection of gas and various surfactant solutions with three different formulation properties in terms of IFT reduction and foaming strength capability into Bentheimer sandstone samples initially saturated with the surfactant solution. Experiments were performed using Bentheimer sandstone cores during, where X-ray CT images were taken during foam generation to find out the stability of advancing front of foam propagation and to map the gas saturation for both the transient and steady-state flow regimes.

Then, a series of numerical simulation was conducted to investigate the effect of surfactant concentration on pressure drop across the core for the foam flooding in the absence of oil. The foam model implemented is based on a local equilibrium and describes dependency of foam mobility reduction factor using several independent functions, such as liquid saturation, foam velocity, oil saturation and capillary number. To this end, the dry-out and gas velocity functions in the foam model were determined from the experimental data obtained at low and high-quality regimes of foam flow at a constant injection velocity. Next, pressure drop profiles of foam flooding at two different surfactant concentrations were modelled to determine the parameters of the surfactant-dependent function in the foam model. The simulation results fit the experimental data of pressure drops very well.
The Hidden Threat of Irreversible Water Blockage in Low Porosity Gas Fields: Learnings from Pre-Production Paleo-Imbibition for Post-Production Field Management in Oman
Authors: Boya Ferrero Maria , Wahaibi Iman , Elshehabi Mohamed , Farsi Ali , Winchester Arlene , Aziz Aamir
Published: April 2018

The high residual gas trapping characteristics of low porosity rock are a considerable challenge for recovery of fields with bottom or edge water. Water lifting and handling is often a practical issue. Perforated intervals may suffer from permanent loss of gas mobility related to hysteresis effects due to imbibition of water (either production induced or paleo-residuals). The discrimination of "trapped" versus mobile gas intervals in a low porosity setting is not straight forward because data can be very deceiving: water imbibed zones may look alike free gas zones, but performance and recovery are quite different

This paper presents a show case of a clastic low porosity formation buried at 4Km depth. Following disappointing performance of the wells due to unexpected water production, the interpretation of pre-production fluid-fill-cycle revealed that a large percentage of the GIIP had been trapped over geological time due to tilting of the structure. Ignoring paleo-imbibition resulted in over-prediction of the recovery and misplacement of wells. Further imbibition of water into prolific zones during production of the field may result in early irreversible water loading of the wells with initial high rates.

A cross-discipline workflow has been put together to quantify field potential and water risk. A fit for purpose reservoir simulation with a focus on the fluid-fill-cycle can explain the performance of the wells to date and predict the expected recovery from paleo-residual volumes. Down flank co-production of gas and water has been proposed as mitigation for water blockage issues: 1st) to potentially delay further water cusping through prolific zones and 2nd) to enhance remobilization of gas trapped in the paleo-residuals zone.

The reported example illustrates the risks of water for gas recovery in low porosity formations, as learnt from a field with paleo-imbibition. We describe diagnostic tools for timely discrimination of paleo-trapped gas volumes to be considered prior to investment decisions, well placement and completions; we suggest fit for purpose models that can be constructed to represent rock and fluid physics without embarking into comprehensive full-field full-hysteresis models; we draw attention to specific permeability modeling guidelines for reservoirs containing significant volumes of low porosity rock to avoid overestimation of production plateau time. We recommend the planning of co-production of gas and water in flank wells to safeguard production from prolific zones in low porosity reservoirs with an aquifer.
CSS: Strategies to Recovery Optimization
Authors: Trigos Erika , Lozano Eduardo , Jimenez Ana Maria
Published: April 2018

This paper was written with the main propose to share the experience of more than ten years of cyclic steam stimulation (CSS) in a heavy oil field with a big amount of challenges such as low injectivity, sanding, steam channeling, low steam efficiency, among others.

For each item identified with a high impact on the CSS production and efficiency, a methodology to analyses and optimization was developed. the first step is identifying the item, recollect the information and quantify the impact; after that, the information is analyzed by the reservoir team, some solution is suggested and evaluated by numerical simulation and other tools; then, the best solution found is apply like a pilot on the field and according to the results it is implemented in a full field scale or replanting until to get the hope results. Finally, corrective actions are taken to avoid similar troubles in the future development of the field. Lesson learners are divulged to the members of the organization.

For the case of low injectivity, this was identifying in the first stage of development of the field; we carried on lab cores to found the presence of swelling shales like the main causes. Inhibitors clays were test on lab and implemented in the first cycles; for the next steps of development we acquired steam generators with a high-pressure setting too. On the other hand, steam channeling was identified in wells with more of five cycles of stimulation; others wells with potential channeling was identified too, and a methodology to inject this kind of wells was development with the help of simulation tools and successfully implemented in field. The injection of other fluids with the steam like nitrogen, foam or gels improved the low steam efficiency; the development methodology is included in the paper.

This papers include a lot of experiences in the improving of cyclic steam stimulation, test lab, numerical simulation and other tools are combined with the field experience obtaining an improve in the oil production. Real data field, CSS information and developed methodologies are included in the paper. For this reason, this paper is useful to future implementation of CSS process and in other fields with similar features.
Influence of Additional Objective Functions on Uncertainty Reduction and History Matching
Authors: La Rosa Almeida Forlan , Nandi Formentin Helena , Maschio Célio , Davolio Alessandra , José Schiozer Denis
Published: April 2018

This paper proposes new objective functions to assimilate dynamic data for history matching, and evaluates their influence on the uncertainty conditioning. Representative events are observed and evaluated separately for the available dynamic data. The proposed objective functions evaluate two specific events: (1) the production transition behavior between the historical and forecasting period, and (2) the water breakthrough time. To assess production transition behavior, the deviation between the latest available historical data is compared with the forecast value, at a specific moment, under forecasting conditions. To assess water breakthrough, the irruption time error is measured in addition to the water-rate objective function. The new objective functions are normalized using the Normalized Quadratic Deviation with Sign, for comparison with conventional objective functions (i.e. NQDS-oil production rate). These additional objective functions are included in a probabilistic and multi-objective history matching and applied to the UNISIM-I-M benchmark for validation. Two history-matching procedures evaluate the impact of the additional objective functions, based on the same parameterization, boundary conditions and number of iterations. The first procedure (Procedure A) includes objective functions traditionally used such as fluid rates and bottom-hole pressure, computed using all the historical data points. The second procedure (Procedure B) considers the same as for A as well as the two additional objective functions. The advantages of including the additional objective functions was the supplementary data used to constrain the uncertainties, improving attribute updates. Consequently, Procedure B generated better-matched models considering the historical period and more consistent forecasts for both field and well behavior when compared to available reference data. The addition of the breakthrough deviation improved the quality of the match for water rates because breakthrough deviation is sensitive to reservoir attributes different to those objective functions related to water rate. The production transition error assisted the identification of scenarios that under or overestimated well capacity. Production transition error also improved the transition of the models from the historical to the forecasting period, reducing fluctuations due to the changes in boundary conditions. Despite the increased number of objective functions to be matched, the improved reliability for forecasting is an incentive for further study. Other representative events, such as oil rate before and after the start of water production could be separated and evaluated, for example. The improved reliability for forecasting supports the inclusion of the proposed objective functions in history-matching procedures.
Novel Evaluation of Foam and Immiscible Gas Flooding in Glass-Silicon-Glass Micromodels
Authors: Hauhs Florian , Födisch Hendrik , Hincapie Rafael E. , Ganzer Leonhard
Published: April 2018

We present a systematic workflow to facilitate the visualization of different fluids behavior/performance. Fluids study in this work are brine, gas and specially foam, during flooding experiments in glass-silicon-glass micromodels. These allow for the detailed evaluation and comparison of the individual flooding experiments. This workflow can then be used as part of screening processes to evaluate the fluid-fluid interaction in a porous medium.

The experimental setup consists of a cabinet-dryer with a camera mounted on top. Micromodels are placed inside the cabinet and PTFE Teflon® tubings are used as connection lines. Fluids are injected using a syringe pump. Pressure is measured via a differential pressure transducer. This setup allows to visualize the entire pore space every 10 seconds. To achieve more comparable results, a black oil is used as the displaced fluid. Brine flooding is used as a benchmark to which results can be compared to. Foam was generated before injection with a mixture of a commercial surfactant and 3 g/l NaCl brine.

The observed behaviour for the three different flooding were in line with the reported in the literature. First, gas flooding depicted the lowest final recovery with 22% of the OIIP produced, with viscous fingering clearly visible. The weak performance of gas was also displayed in the recorded differential pressures. No effect on pressure due to gas injection was observed during the flooding. Second, the brine flood performed better than the gas flood, where 36% of the OIIP was ultimately recovered. Due to the more favorable mobility ratio of brine and oil this improvement was to be expected. Third, foam flooding achieved the best oil recovery with 58% of the OIIP produced. Pore blocking and the thus increased areal sweep efficiency is the reason for this improvement. Differential pressure behavior for foam and brine flood was similar: A steep pressure decrease after entering the model until breakthrough was observed, although foam had a higher initial differential pressure than brine before entering the model. The high initial pressure difference to the brine flood, is assumed to be due to the compressibility of the individual foam bubbles present in the tubing.

The workflow presented in this paper, could lead to a fast and economical addition to EOR screening processes. Due to only small volumes of fluids being required to get qualitative and quantitative results. This, in turn could provide relevant insight for foam and immiscible process understanding and modelling.
Kerogen Maturation Effects on Pore Morphology and Enhanced Shale Oil Recovery
Authors: Bui Khoa , Akkutlu I. Yucel , Zelenev Andrei , Hill William A.
Published: April 2018

Characterization studies of organic-rich shale oil reservoirs have revealed significant volumes of hydrocarbon fluids in kerogen. However, the recovery from kerogen pores is challenging due to amplified fluid-solid interactions. New methods can be developed for improved recovery targeting oil from kerogen pore space by modifying the forces of molecular interactions using chemical injection. A highly-developed kerogen pore-network is required for the penetration and delivery of chemical agents that are expected to function in the confined space, such surface active agents. Using advanced computational chemistry tools, the objective of this paper is to show that the maturation (the exposure to high temperature, high pressure) of kerogen during catagenesis relates to the quality of the kerogen pore network such as pore size and shape, and plays important role in the action of added chemicals in the EOR processes.

A new molecular dynamics simulation approach is developed applying dramatic changes to the organic chemicals system temperature to mimic varying degree of maturation. Simulation focuses on Type II kerogen, as it is the most common overall source of presently produced hydrocarbons. Two different chemical structures of type-II kerogen (C175H102N4O9S2, C242H219N5O12S2) are used as the building blocks to simulate the solid kerogen. The molar fractions of the elements are controlled to satisfy the overall H/C and O/C ratio of type-II kerogen in the oil window. The simulated hydrocarbon fluid consists of nine different types of molecules: dimethylnaphthalene, toluene, tetradecane, decane, octane, butane, propane, ethane and methane. The simulation box containing these molecules is subjected to a slow quenching process, which continues down to the reservoir temperature and pressure conditions. The effects of maximum temperature and the rate of quenching on the pore morphology of kerogen and the distribution of oil in the pore-network are discussed. We explain how kerogen pore morphology is controlled by the quenching rates. Next, we simulate the interaction of microemulsion droplets with the digital kerogen.

Results show that the microemulsion droplets posess elastic properties which allow them to squeeze through the kerogen pores smaller than the droplet's own diameter and to adsorb at pore wall surfaces. One major benefit associated with the use of microemulsions is the ability of the droplets to transport and deliver solvents and surfactants to different parts of the pore network. Our work shows that solvents and surfactants with particular features can be delivered in the form of a microemulsion droplet into oil saturated kerogen pore network and influence the oil mobility.
Temperature and Geometry Effects on the Fracture Surfaces Dissolution Patterns in Acid Fracturing
Authors: Aljawad Murtada Saleh , Zhu Ding , Hill Alfred Daniel
Published: April 2018

Modeling acid fracturing operations in carbonate formations is performed to evaluate the possible improvement in well productivity. Models are developed to mainly estimate the acid penetration length and the fracture surfaces etched-width profile. Variable combinations of these two parameters produce a significant difference in the fracture productivity. To better estimate these parameters, a reliable fracture propagation model should be coupled with the acid reaction/transport model. Simulating weak acids or dolomite formations reactivity requires the inclusion of a heat transfer model. The model provided in this study couples these factors as fractures propagate to finally obtain the fracture conductivity distribution along its length.

The fracture propagation model continuously updates the domain for the acid model. A transient acid convection and diffusion equation is solved and the fracture etched-width profile is calculated. An iterative procedure is implemented in a temperature dependent kinetic model which is stopped when both the temperature and acid solutions converge. When injection stops, acid etching and the fluids temperature are updated as the fracture closes. As the final etching profile is drawn, conductivity is calculated using a correlation that considers formation heterogeneity.

Coupling fracture propagation shows a significant difference on the acid model solutions compared to that assuming constant fracture geometry. For extremely high Peclet number that represents a very retarded acid system, a constant drop in the etched-width value until reaching zero at the fracture tip is theoretically obtainable. For lower Peclet numbers, the etching profile is shown to be sharply declining towards the fracture end. This is in contrast with the non-coupled approach from which a uniform etching profile is obtained at moderate to high Peclet numbers. It is also observed that the simulation of acid injection in non-coupled, constant fracture geometry always overestimates the acid penetration distance. The etched-width distribution and the acid penetration length are temperature sensitive, especially in dolomite formations. Temperature coupling shows that the maximum etching in dolomite formations occurs away from the fracture entrance as acid reactivity increases. It also shows that the cooling effects of the first stage pad fluid on improving the acid penetration distance is limited.

Simulating acid fracturing operations assuming constant final fracture geometry and an average single temperature is time efficient but results in inaccurate solution. This paper quantifies the effects of integrating fracture propagating and heat transfer models on the acid etching pattern from which, a better estimate of the fracture productivity is expected.
Testing and Improvement of Well Layout Optimisation Methods for Geothermal Reservoir Production
Authors: Lu Minjie , Siffert Deborah , Mathieu Jean-Baptiste , Garcia Michel , Gosselin Olivier R.
Published: April 2018

The development and management of geothermal reservoirs is complicated and expensive, the maximum potential geothermal energy recovery highly depending on the choice of optimal or at least relevant well locations. Within the framework of the GEOTREF research project, a multidisciplinary platform for innovation and demonstration activities for the exploration and development of high geothermal energy in fractured reservoirs, a method has been developed to optimise well layouts (location and depth) based on geothermal reservoir production performance criteria (objective functions). Objective functions such as available thermal exergy, electrical power output, leftover energy rate and simplified net present value are proposed in this paper to be used as performance criteria for identifying optimal well layouts.

The optimisation method uses the principle of superposition as a proxy-based method to simulate the production of a well layout by summing the effects of individual injection and production wells of the layout simulated separately. Using this method, the computation time required to seek optimal well layout designs is significantly reduced. The well layouts are defined based on a number of injection and production wells to be selected among many possible well locations and depths. They are all simulated using the principle of superposition and ranked according to the selected objective function. The optimal well layout is the one maximising the objective function.

Data from an actual case study is used to evaluate the method. The four objective functions are tested using reservoir simulations and sensitivity analysis based on various production parameters. The results show that the proxy-based method can simulate the performances of well layouts with sufficient accuracy, the discrepancy between proxy-based simulations and full simulations increasing with production rate. More important, the method proves to be consistent by preserving the ranks of the top one hundred well layouts under all high, medium and low production/injection rates. Preserving the ranks is the required condition that makes the proposed method reliable for seeking optimal well layouts in geothermal reservoirs. The choice of an objective function does not drastically change the areas that are recognised as good or bad for production or injection wells. Provided relevant data are available as input to the most comprehensive objective functions (i.e., electrical power output, simplified net present value), this study concludes that the proposed method is highly reliable to identify optimum well layouts in geothermal reservoirs in a relatively short computation time.
Evolution of Permeability in Sand Injectite Systems
Authors: Hu Yu , Gan Quan , Hurst Andrew , Elsworth Derek
Published: April 2018

Sand injectite complexes comprise kilometer-scale clastic intrusion networks that act as effective conduits for the migration, accumulation and then recovery of hydrocarbons and other fluids. An equivalent continuum model is constructed to represent a sand injectite reservoir, coupling stress and fluid flow in fractured rock using the continuum simulator TOUGHREACT coupled with FLAC3D to follow deformation and fluid flow. A permeability model, which uses staged percolation models, is proposed to improve permeability estimation of fracture networks by accommodating four different levels of fracture connectivity. This permeability model is confirmed against field and laboratory data, corresponding to the different connectivities of fracture networks. The new constitutive permeability model is incorporated into the coupled hydro-mechanical simulator framework and applied to sand injectites with the analysis of permeability evolution mechanisms and mechanical sensitivity. The results indicate that when the magnitudes of principal stresses increase in a constant ratio, normal closure is the dominant mechanism in reducing fracture aperture and thereby permeability. Conversely, the evolution of stress difference can accentuate aperture and permeability due to an increase in shear dilation for critically or near-critically oriented fractures. Also, the evolution of aperture and related permeability of fractured rock are more sensitive at lower stress states than at higher stress states due to the hyperbolic relationship between normal stress and normal closure of the fractures.