bluuebunny/crossref_metadata_2025 huggingface dataset:
Porosity and Tensile Properties of Rhizoid Porous Structure Fabricated Using Selective Laser Melting
Authors: Ishibashi Shinji , Shimada Keita , Kanetaka Hiroyasu , Tsukuda Masaki , Mizoi Takumi , Chuzenji Masataka , Kikuchi Shoichi , Mizutani Masayoshi , Kuriyagawa Tsunemoto ,   Graduate School of Engineering, Tohoku University 6-6-01 Aramaki Aza-Aoba, Aoba-ku, Sendai, Miyagi 980-8579, Japan,   Graduate School of Dentistry, Tohoku University, Sendai, Japan,   Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan,   Department of Mechanical Engineering, Faculty of Engineering, Shizuoka University, Hamamatsu, Japan
Published: July 2020

The reduced density of the autogenous bone around metal medical implants forces joint replacement patients to undergo revision surgery. The loss of bone density is caused by a significant difference in the elastic modulus between implants and autogenous bone. Various studies have attempted to reduce the elastic modulus of the implant to close the large gap in the two moduli. Porous metal is a promising material for reducing the elastic modulus of implants, but it is difficult to fabricate a closed-cell structure like bone using conventional porous metal fabrication methods. In this study, porous Ti-6Al-4V was prepared by selective laser melting, then its porosity was evaluated by X-ray computed tomography. Additionally, tensile test specimens of the porous structure were prepared and the effect of pores on the tensile properties was evaluated. Depending on the energy density, the structure of the porous body was found to form both closed- and open-cell structures. In the tensile specimens that showed the most favorable results, the elastic modulus was reduced by approximately 90%, and the tensile strength exceeded that of the annealed material. This indicates that a metal implant that has a low elastic modulus while maintaining strength can be obtained.
Influence of Grooved Plate Cross-Sectional Shape on Bending Phenomena in Laser-Quenching Forming Process
Authors: Manabe Yuki ,   Doshisha University 1-3 Tataramiyakodani, Kyotanabe-shi, Kyoto 610-0394, Japan, Nishida Hiromichi , Hirogaki Toshiki , Aoyama Eiichi
Published: July 2020

This research proposes a method to achieve laser quenching and laser forming simultaneously. This technique uses a diode laser to produce thin steel sheet-assuming parts, such as springs and hinges. Energy and time are saved by combining the advantages of laser quenching, which has high input heat efficiency, and laser forming, which, unlike press molding, does not require metal molds. In this study, laser-quenching molding was performed for an entire thin steel plate, and the influence on warping was investigated. Furthermore, the proposed method was evaluated under repeated quenchings for different cross-sections of a workpiece. The results indicated that the technique prevented bending deformation during the next laser scan and reduced warping by increasing the second moment of area of the entire workpiece.
Experimental Analysis and Anti-Sway Control of Jigiri Behavior in a Nursing Lift
Authors: Funato Kazuhiro , Kenmotsu Yuichiro , Tasaki Ryosuke , Sakakibara Toshio , Kakihara Kiyoaki , Terashima Kazuhiko ,   Toyohashi University of Technology 1-1 Hibarigaoka, Tempaku, Toyohashi, Aichi 441-8580, Japan,   Aoyama Gakuin University, Sagamihara, Japan,   Fukushimura Hospital, Toyohashi, Japan,   KER Co., Ltd., Toyokawa, Japan
Published: July 2020

In today’s situation with high needs for care, a transfer work, among various assisting works, produces particularly large physical burden. The burden could result in not only diseases including waist pain but also resignation of care workers. A nursing lift used to reduce the burden lifts up a care receiver by using a wire or mechanical structure, causing sway. The sway not only makes the care receiver uncomfortable but also causes a risk of unintentional collision. To prevent such a situation, carers need to assist care receivers by holding them while simultaneously operating equipment and paying attention to the care receivers, which is not preferable from a viewpoint of work safety. In this study, we experimentally analyzed and discussed sway of a person when he/she is lifted up. On the basis of an analysis result, we propose an automatic control method of dynamical speed change for safe lifting works, which is applicable to ordinary nursing lifts.
Study of the Warp Removal Process for a Thin Substrate: Development of a Correction Processing System Using a Freezing Pin Chuck
Authors: Yoshitomi Kenichiro ,   National Defense Academy of Japan 1-10-20 Hashirimizu, Yokosuka, Kanagawa 239-8686, Japan, Une Atsunobu
Published: July 2020

High precision is required for thin substrates used in the manufacturing processes for semiconductor devices and flat panel displays, and the required precision for substrate warp becomes more stringent every year. However, it is difficult to remove the warp efficiently utilizing the current grinding and polishing methods. One of the causes is deformation of the substrate during clamping. For this reason, a freezing pin chuck has been developed as a clamping technology that does not deform the substrate. A freezing pin chuck that uses the adhesion of frozen liquid can be designed with a substrate clamping force that can withstand the processing force. In this study, we developed a correction processing system that utilizes a freezing pin chuck to remove the warp of the thin substrate. The developed correction processing system can perform the grinding and polishing processes while clamping the substrate without deformation using a freezing pin chuck, and has a non-deformation clamping capacity that suppresses substrate deformation to 1/10 or less for a substrate with an initial warp of 100 μm. In addition, the newly devised additional application method has made it possible to increase the clampable warp by approximately twice that of the ordinal application method, and improves the clamping force. The results of the grinding and polishing experiments revealed that the correction processing system can obtain the same planarized profile as that when a vacuum pin chuck is utilized, while cooling the substrate surface during processing to 5°C or less, and also demonstrated that it can be applied to correction processing.
The Role of Wisdom on Loneliness in Single Women
Authors: Pratiwi Lila , Komariah Komariah
Published: July 2020

The present study aims to see the role of wisdom on loneliness in single women. The research was carried out through a quantitative approach with regression statistics. A total of 100 single female undergraduate students and workers aged 18-25 years participated in this study. Data was collected through a questionnaire consisting of (1) Brief Wisdom Screening Scale by Glück at al (2013), to measure wisdom, and (2) SELSA-S (Social and Emotional Loneliness Scale for Adult) developed by Ditomasso et al (2004) to measure feelings of loneliness. The reliability value for the Brief Wisdom Screening Scale (BWSS) was 0.723, while the reliability value for Social Emotional Loneliness Scale for Adult (SELSA-S) was 0.754. The result showed there was 10.7% effects of wisdom on loneliness in single women (= 0.327 with R2 = -0.107 and p <0.001). It is concluded that there is a significant role of wisdom on feelings of loneliness. The study also proposes that individuals may lower the level of loneliness by increasing their wisdom.
Relationship of Innovativeness with Social Justice: an Example from Fishermen Community in Pulau Harapan, Indonesia
Authors: Syaban Mohammad Balya Ali
Published: July 2020

This   research   aims   to   determine   the   relationship   between   the   innovativeness   of fishermen on the Islands with social Expectations North thousand islands. The method used was a survey with  the  study  involving  75  sample  correlations.   There are  two instruments  in  measurement  to  the  study  of  social  justice  (reliability  =  .923),  and innovativeness (reliability =   .952). This research data were analyzed using regression correlation which is then verified by test-t and F-test. The results of this research show that there  is  a  positive  and  significant  correlation  between  innovativeness  with  social justice.  It can  therefore  be  inferred  if  the  fisherman's  increased  social  justice  then innovativeness will be a consideration.
Seeing Nature and the Philosophy of Banjar Through Banjar Traditional Pantun
Authors: Effendi Rustam
Published: July 2020

Banjar traditional rhymes are rhymes that lived and prospered around 1900 and below. The calculation from 1900 down refers to the theory that traditional literature lived and developed two generations ago and below. Traditional Banjar rhymes are expressed only in spoken language. If traditional Banjar rhymes are expressed only in spoken language, then the contemporary Banjar rhymes, in addition to being expressed in spoken language, are also expressed in written language, even expressed through cyberspace, such as whats up, facebook, and other virtual worlds (digital literature). The Banjar Pantun is supported by traditional Banjar people, who are mostly illiterate. Therefore, the content of rhymes is very vulgar (to be honest, revealing things as they are) and reflects the natural condition at the time the rhymes were made, and reflects the original philosophy of Banjar, which has not been contaminated by foreign cultures. Research on the Banjar traditional pantun is very important and very urgent. Banjar rhymes which are verbal are stored in the memory of informants, most of which are elderly. Therefore, various Banjar rhymes must be immediately recorded and analyzed in accordance with the explanation of the informant. The results of this study conclude that the natural atmosphere reflected from the Banjar rhyme is a calm, peaceful atmosphere, fresh wind blowing, deep rivers and clear water, a sense of family, shady trees, community activities back and forth from village to village, and prosperity and the happiness of life. Some of the philosophy of life of the Banjar people reflected in the traditional Banjar rhyme are: (i) regard the teaching profession as the noblest profession outperforming other professions, (ii) Appreciation to Mr. Tuan Haji (someone who has performed the hajj) and submit to his advice, (iii ) ideal women for Banjar people are white women and like to smile, (iv) true longing and jealousy will not be able to be cured, (v) people who love each other are people who remember each other, (vi) new people remember and appreciate his family and hometown when afflicted by unfortunate overseas, (vii) contemplate fate and accept destiny if fate has been determined by the Almighty.
Sufi Order of Kubrovia and Naqshbandi Are an Integral Part of Pilgrimages Tourism In Central Asia
Authors: Mukhamednazarova I.V. , Elvira Xoschu , Nizamutdinov T.M.
Published: July 2020

In recent years, the tourism potential of Uzbekistan has been developing rapidly. According to statistics, in 2019, 6.748 million peoples visited Uzbekistan, which is much more compared to 2018 (5.346 million). Most tourists came from the CIS countries and neighboring countries. It is of great interest to tourists if we are talking about representatives of Muslim countries, both earlier and today, represent the pilgrimage places of our main cities of the republic. It is said that if graceful light descends from heaven to all cities of the world, then in Bukhara it rises from the earth with a pillar to heaven, and the source of this light is a large number of shrines that are on this blessed land. In this article, we will analyze the origins of the Sufi movements that existed in Uzbekistan. Indeed, thanks to them, religious tourism is actively developing in our country, or as it is customary to call it in the East, “ziyorat” literally “visiting holy places”.
Recreational Tourism in the World and Its Perspectives in Uzbekistan
Authors: Nazokat Khamidova , Mardonovna Turdiyeva Nargiza
Published: July 2020

The numerous forms of health tourism are gaining an enhanced presence in world tourism these days and this is also true of some countries' economic success. Health tourism with ongoing development over the past decade has seen a dynamic development, primarily in the area of wellness tourism at both national and international levels. Consequently, the advance of health tourism is given significant importance in developing countries. This form of tourism is considered one of the spheres of great importance to which the population pays attention. Health tourism encourages both the prevention of physical and emotional exhaustion and the treatment of many chronic illnesses. For this reason, for a more productive and healthy vacation, tourists go to resort areas, which are the main component of the medical health tourism. Medical tourism on a global scale is one of the most dynamically developing types of tourism. So, according to the forecast of the World Health Organization Conservation Agency (WHO), by 2022 tourism together with the healthcare sector will become one of the most priority areas for the development of national economies. In this article advantages of health and recreational tourism, the ways of providing this service in different countries, recreational facilities, infrastructure   and resource of Uzbekistan are going to be represented. Besides that, some problems in local recreational tourism with the example of “Zaamin” Sanatorium in Jizzakh region of Uzbekistan based on the personal communication are going to be expended.
The Touristic Potential of Aral Sea and an Innovative Approach in its Effective
Authors: Sharof Rashidov Rustamjon
Published: July 2020

The article mainly illustrates Aral Sea as one of the largest man-made environmental devastation and provides eligible programs that aims at remedying humanity mistake partially through converting the disastrous territory into an eco-touristic destination. Together with exploring adverse impacts of Aral Sea on the locals, the study also examines attractiveness and touristic potential of the territory which will then leads creating an attractive image of the land to ensure a surge of foreign investment. This is the strategic thinking that can reform the prospective revenue generated by the use of Aral Sea as a tourist destination. Based on the identified problems and examined potentiality, the prospects for the further development of integration processes focused on the effective use of the area will be determined.
Empowerment Of School Committees In Improving The Quality Of Education Basic Schools Of Indonesia-Malaysia State Border
Authors: Sahrul Muhammad , Mawar Mawar , Tuti Retnowati WD , Handayani Nida
Published: July 2020

The purpose of this study is to see how the form of empowerment of school committees in improving the quality of education especially in elementary schools. The research method used is descriptive qualitative approach with data collection techniques namely observation, interviews, and documentation. Research findings The existence of a school committee is an important element in improving the quality of school education services, its existence with all the tasks and functions it has can play a role in realizing better quality education services. Efforts to empower school committees are carried out in various ways although they are still not ideal as stated in the regulations related to school committees. In principle, so far the participation of school committee members and the form of empowerment of school committees is still limited to routine meetings and the fulfillment of supporting facilities for student learning facilities that are done voluntarily by school committees. Based on this, the efforts to empower school committees have been made but are still limited to routine agendas that are not yet optimal as the actual duties and functions of school committees.
Current Problems of Personnel Training for the Tourism Sector in Uzbekistan
Authors: Mukumova Nargis Nuriddinovna
Published: July 2020

The article considers issues relating to existing system of personnel training for the tourism sector. In connection with the active development of this sector of the economy has appeared the need for clear interaction between the system of professional education and the labor market. Despite the fact that a large number of special educational institutions and higher educational institutions train personnel for the tourism industry, there is a shortage of qualified personnel in the tourist job market. According to experts, today the majority (up to 75%) of employees of tourism companies do not have education of a specialist in the field of tourism. Currently, the market situation is such that graduates of specialized educational institutions do not meet professional requirements that meet international standards. Today's specialists have a low professional level, so hotels and travel agencies that have their own specialist training programs have to re-train the hired employees. Training and retraining of personnel in the field of tourism can become one of the main advantages of the organization, as the quality of the services provided depends on the qualifications of the personnel, and the satisfaction of guests in the service sector is achieved by the competence of the personnel. The purpose of improving the professional training of personnel for the tourism industry is to create a sustainable development of the system of professional training that would meet the needs and development of the individual, the state and society as a whole, which would improve the quality of professional training of specialists in the field of tourism.
Narrativas de vida e direitos humanos: reflexões sobre os direitos das mulheres e estado de exceção
Authors: Souto Luana Mathias
Published: July 2020

Este artigo tem por objetivo analisar os direitos das mulheres no contexto brasileiro, principalmente, seus direitos reprodutivos. Para atingir esse propósito, o artigo por meio da combinação entre Direito, Filosofia e Literatura tenta repensar por que as mulheres não possuem voz quando decisões sobre seus direitos são tomadas? Metodologicamente, utiliza-se de revisão bibliográfica, a partir da obra "O conto da Aia", escrita por Margaret Atwood (2006) e os conceitos de "homo sacer" e estado de exceção desenvolvidos pelo filósofo Giorgio Agamben (2004; 2007) para ilustrar como as narrativas de vida podem promover os direitos humanos.
Whirlwinds in the narrative of "The Devils of Loudun", by Aldous Huxley: a study on truth, fiction, justice
Authors: Bentes Hilda Helena Soares
Published: July 2020

This paper analyzes the “historical narrative” novel "The Devils of Loudun", by Aldous Huxley, which tells the story of a supposed demonic possession case happened in a convent of Ursuline nuns in the beginning of the 17th century. It is about a real event that brings up a series of thoughts on the importance of the law, as well as the role of literature and philosophy, fiction, truth, justice and its relation with vengeance and revenge. The objective is to depart from the theory of law in order to study the literary work. Also, this paper aims at establishing to what extent the process of telling the truth can be twisted by revenge, as a primitive instinct of annihilating an enemy. It is a theoretical investigation, accomplished by bibliographic research, with an interdisciplinary approach between law and literature.
Encontros, desencontros e reencontros: a interpretação literal nos espaços da argumentação jurídica e literária
Authors: Torres Rodríguez Oscar Enrique
Published: July 2020

Partindo, por um lado, da existência da interpretação literal nas esferas jurídica e literária e, por outro lado, de seu diferente status nesses campos de estudo, surge a seguinte questão: como se pode estabelecer um ponto de encontro entre o status do método de interpretação literal nos campos da crítica literária e da interpretação jurídica? Para esse fim, propõe-se a adoção de uma perspectiva pragmática da argumentação em geral, a fim de tentar revelar um ponto de reencontro entre a interpretação literal nos espaços da argumentação jurídica e literária.
Reviving a Mature Field in Ecuador by Rethinking Energy Sustainability and Reservoir Management
Authors: Astudillo Ricardo , Orellana Ney , Lozada Santiago , Añazco Jorge , Bailón Luis , Espín Jorge , Freire Juan , Gaibor Andrés , Martínez Edsson , Muñoz Edwin , Padilla Carlos , Román Servio , Tamayo Telmo , Villegas Santiago
Published: July 2020

This paper summarizes the strategies implemented in a mature oil field in Ecuador to revive its production by improving energy efficiency, increasing fluid production and incorporating proved reserves. Results are shown in terms of the field energy efficiency index, energy consumption on ESPs, oil production, annual production decrease tendency and reserves incorporation.

The Choke Model philosophy was implemented as a strategy for field development optimization. This methodology allowed the operator to identify that the main chokes were the production wells and the power. By using divergent and convergent thinking techniques focused on these chokes, four main strategies were selected: reduce the pipe diameter size of a fluid line, artificial lift system energy assessment, reactivate closed wells and recomplete others. Complete description of the methodology is provided in detail to permit readers to analyze this successful case.

The reduction of pipe size diameter of a fluid line increased the mobility of the fluid from the well pads to the plant, eliminated the recirculation of water and thus increase the energy efficiency indicator of fluid handling from 9,770 to 10,190 BFPD/HP. The energy assessment of the artificial lift systems identified the inefficient wells that were scheduled for ESP redesign and technology upgrade with an energy improvement of 30%. All these energy efficiency improvements lead to rise fluid production.

Based on the possibility to increase fluid production, wells reactivations, ESP upsizing’s and recompletions were planned. The team used a screening process to optimize candidates, gaining 2,010 BOPD, in average, over the baseline production profile since September 2017 to December 2018.

The activities performed and well interventions diminished the annual oil production decline rate from 14% to 8%, allowed the operator to incorporate 4.8 MBBLS of proved reserves in 2018 and generate 7.6 MUSD of free cash flow in the same year.

All the strategies were successfully achieved, and they accomplished the objectives of reviving a mature field, extending its life and generating value for the operator. None of the previous were possible without rethinking energy sustainability and reservoir management.

The novelty of this work is the multidisciplinary approach and innovation methodology implemented to provide solutions to operational field chokes by identifying feasible projects in terms of technique, time and economics.
A Thorough Review and Latest Advances in Shale Reservoirs: Seismic to Surveillance
Authors: Temizel Cenk , Canbaz Celal Hakan , Gok Ihsan Murat , Roshankhah Shahrzad , Palabiyik Yildiray , Deniz-Paker Melek , Hosgor Fatma Bahar , Ozyurtkan Hakan , Aksahan Firat , Gormez Ender , Kaya Suleyman , Kaya Onur Alp
Published: July 2020

As major oil and gas companies have been investing in shale oil and gas resources, even though has been part of the oil and gas industry for long time, shale oil and gas has gained its popularity back with increasing oil prices. Oil and gas industry has adapted to the low-cost operations and has started investing in and utilizing the shale oil sources significantly. In this perspective, this study investigates and outlines the latest advances, technologies, potential of shale oil and gas reservoirs as a significant source of energy in the current supply and demand dynamics of oil and gas resources.

A comprehensive literature review focusing on the recent developments and findings in the shale oil and gas resources along with the availability and locations are outlined and discussed under the current dynamics of the oil and gas market and resources. Literature review includes a broad spectrum that spans from technical petroleum literature with very comprehensive research using SCOPUS database to other renowned resources including journals and other publications. All gathered information and data are summarized. Not only the facts and information are outlined for the individual type of energy resource but also the relationship between shale oil/gas and other unconventional resources are discussed from a perspective of their roles either as a competing or a complementary source in the industry. In this sense, this study goes beyond only providing raw data or facts about the energy resources but also a thorough publication that provides the oil and gas industry professional with a clear image of the past, present and the expected near future of the shale oil/gas as it stands with respect to other energy resources.

Among the few existing studies that shed light on the current status of the oil and gas industry facing the rise of the shale oil are up-to-date and the existing studies within SPE domain focus on facts only lacking the interrelationship between heavy and light oil as a complementary and a competitor but harder-to-recover form of hydrocarbon energy within the era of rise of renewables and other unconventionals. This study closes the gap and serves as an up-to-date reference for industry professionals.
Limited Access Ranging Solution – Mitigation of Significant Anti-Collision Issues
Authors: Hinke Sean , Hooff Gerritt
Published: July 2020

This paper explores four unique case studies where a novel limited-access ranging system was used in real world examples of well placement with close-proximity drilling applications. The case studies highlight enhanced recovery and reduced complexity for the overall well construction process. The method uses a gradient ranging system along with surface excitation to create an active magnetic field along the target wellbore to acquire a distance and direction measurement. This arrangement eliminates the need for the typical access-dependent ranging conveyance using coiled tubing or wireline systems. With this approach, several logistical and technical constraints are removed, making several unique solutions possible, such as ranging to abandoned wells and to wells with casing damage or other obstructions, and as well as high-temperature applications as no intervention is required to the target wellbore.

The first case study used magnetic ranging to an abandoned wellbore in an approach similar to drilling a standard Steam Assisted Gravity Drainage (SAGD) injector well. The second study highlights an anti-collision scenario which required toe-to-heel ranging to an abandoned wellbore. The third used magnetic ranging as an anti-collision tool performing toe-to-heel ranging to a currently producing wellbore where completion tools were left in the hole. The fourth scenario used the technology to drill a parallel well where a casing and tubing obstruction limited the ability to run traditional ranging equipment.

Through this paper, the authors will illustrate the benefits of this technology in their use in Steam Assisted Gravity Drainage drilling applications and expand on potential benefits of this technology in other close-proximity drilling applications for either paralleling or anti-collision purposes.
Development Strategies in the Sureste Salina Del Istmo Basin: Sustainable Production Replacement Options
Authors: Zarea Maziar , Mohamed Kareemah
Published: July 2020

With the advent of the Mexican Energy Reform, foreign companies have flocked to the southern Gulf of Mexico (GoM) attempting to replicate the same level of commercial success as seen in the U.S. GoM. There have been recent notable discoveries as well as significant untapped potential in existing discoveries (approximately 12 Bboe 2P remaining recoverable reserves), largely in the shallow waters of the infrastructure-rich, re-emerging Sureste basin. These fields present a near-term path to production to stem Mexico's production decline. In the Sureste Basin, 54% of offshore fields have field sizes of less than 100 MMboe 2P recoverable reserves and are in the discovery/appraising phase. We have developed a screening method which ranks field candidates for near term development to add much needed oil production.

Additionally, for these top ranked fields, through leveraging a combination of the following factors can result in 3.4 Bboe of 2P recoverable reserves monetized within 3-4 years with an overall cost reduction.

The concept of "Hub and spoke" field development can be used to approach to utilize existing platform capacity and tie in marginal fields. Utilizing modular and standardized platform configurations which can result in a compression of development cycle times by using "off the shelf" designs. By reducing non-productive rig days, there can be a overall need for less rig mobilization. Digitalization enabled potential change in the operating model, facing a potential 60% reduction in offshore staffing due to relocation of maintenance crews onshore.

To achieve this cost reduction target identification of field candidates is vital. This screening methodology employs a cross functional approach to optimizing subsurface reserves while incorporating above-ground risk, linking existing infrastructure capacity and new technology deployment. This methodology was applied to 30 discoveries in the Sureste basin which have never been produced and modeled 3 cases evaluated on time to first production and cost reduction. This can contribute to the enhancement of Mexico's energy sector and present acquisition targets to operators and infrastructure owners. These concepts may be applied to other analogous asset types.
A Two-Phase Non-Linear One-Dimensional Flow Model for Reserves Estimation in Tight Oil and Gas Condensate Reservoirs Using Scaling Principles
Authors: Ruiz Maraggi Leopoldo M. , Lake Larry W. , Walsh Mark P.
Published: July 2020

A common approach to forecast production from unconventional reservoirs is to extrapolate single-phase flow solutions. This approach ignores the effects of multi-phase flow, which exist once the reservoir pressure falls below the bubble/dew point. This work introduces a new two-phase (oil and gas) flow solution suitable to extrapolating oil and gas production using scaling principles. Additionally, this study compares the application of the two-phase and the single-phase solutions to estimates of production from tight oil wells in the Wolfcamp Formation of West Texas.

First, we combine the oil and the gas flow equations into a single two-phase flow equation. Second, we introduce a two-phase pseudo-pressure to help linearize the pressure diffusivity equation. Third, we cast the two-phase diffusion equation into a dimensionless form using inspectional analysis. The output of the model is a predicted dimensionless flow rate that can be easily scaled using two parameters: a hydrocarbon pore volume and a characteristic time. This study validates the solution against results of a commercial simulator. We also compare the results of both the two-phase and the single-phase solutions to forecast wells.

The results of this research are the following. First, we show that single-phase flow solutions will consistently underestimate the oil ultimate recovery factors for solution gas drives. The degree of underestimation will depend on the reservoir and flowing conditions as well as the fluid properties. Second, this work presents a sensitivity analysis of the PVT properties that shows that lighter oils (more volatile) will yield larger recovery factors for the same drawdown conditions. Third, we compare the estimated ultimate recovery (EUR) predictions for two- and single-phase solutions under boundary-influenced flow conditions. The results show that single-phase flow solutions will underestimate the ultimate cumulative oil production of wells since they do not account for liberation of dissolved gas and its subsequent expansion (pressure support) as the reservoir pressure falls below the bubble point. Finally, the application of the two-phase model provides a better fit when compared with the single-phase solution.

The present model requires very little computation time to forecast production since it only uses two fitting parameters. It provides more realistic estimates of ultimate recovery factors and EUR, when compared with single-phase flow solutions, since it considers the expansion of the oil and gas phases for saturated flow. Finally, the solution is flexible and can be applied to forecast both tight oil and gas condensate wells.
Unified Oil and Water Fractional-Flow Functions: Improving Waterflood Performance Analytical Modeling Techniques
Authors: Tillero Edwin , Mogollon José Luis
Published: July 2020

Applying simpler and more powerful waterflood performance analytical modeling tools to history match and forecast fluid (oil and water) production rates is always a subject of interest. Increasing improvements of these no grid-based tools trigger their use as predictive and trustworthy precursors of grid-based modeling, providing significant insights and allowing a previous assessment of historical and future waterflood performance without a significant time- and investment-consuming modeling.

Setting up a unified fractional-flow model (UFFM), that considers both the traditional Buckley-Leverett-based stable fractional-flow model (BLBFFM) and instabilities due to oil viscous-fingering effect, to accurately predict the oil recovery from traditional waterflood performance analytical modeling tools is the objective of this paper. The unification is based on using appropriate kro/krw vs. water saturation expression that considers viscous-oil effect based on the effective finger model (EFM), allowing the substitution of a classic semilog linear relationship of kro/krw vs. Sw (constant coefficients A and B) by a unified nonlinear oil-water relative permeability ratio.

This UFFM approach aims to boost the analysis from well-known waterflood performance analytical methods: water-oil ratio (WOR), X-plot, Y-function and the capacitance-resistance model (CRM). Such waterflood performance diagnosis methods, traditionally based on the BLBFFM, were redefined by using the new UFFM. Conceptual and field cases were tested using new definitions to evaluate impact on ultimate oil recovery and various reservoir parameters.

Results demonstrated that unified approach improves reliability when estimating oil recovery for stable and unstable waterfloods. As expected, they quantitatively yield, for example, that the greater the viscous-fingering effect, the lower the viscous-oil recovery.

The universalization of fractional-flow functions (fw and fo) by incorporating UFFM upon all traditional waterflood performance methods based on BLBFFM can allow insights of important physical phenomenon that affect relative permeability, such as the oil-water viscosity ratio, injection rate, and known physical parameters affecting ultimate oil recovery.
Sand Control Optimization for Rubiales Field: Trade-Off Between Sand Control, Flow Performance and Mechanical Integrity
Authors: Mayorga Cespedes Edgar Alberto , Roostaei Morteza , Uzcátegui Alberto A. , Soroush Mohammad , Izadi Hossein , Hosseini Seyed Abolhassan , Schroeder Brad , Mahmoudi Mahdi , Gomez Dionis M. , Mora Edgar , Alpire Javier , Torres Joselvis , Fattahpour Vahidoddin
Published: July 2020

Designing/Selecting the proper sand control mechanism for horizontal wells in unconsolidated heavy-oil reservoirs tend to be under-looked in some cases. Stand-alone completions pose some sand control challenges, which could jeopardize the oil production or even lead to critical problems. Massive sand production, screen/formation plugging, formation of velocity hot-spots and mechanical integrity failures are some of the well-known issues. This study attempts to optimize the sand control design for horizontal wells in a heavy-oil field in Colombia.

A careful selection of representative core data was made to study the variation of sand Particle Size Distribution (PSD) within the development area. Reservoir fluid properties were analyzed. Based on PSD variation and current design criteria in the industry, several seamed slotted-liner configurations were proposed as an alternative completion for testing. Later, a series of large-scale Sand Retention Tests (SRTs) were performed to assess the selected alternatives under typical field production conditions. Effects of aperture size and open to flow area (OFA) were investigated to evaluate flow and sand control performance.

This investigation started by a detailed study of the PSD, particle shape variation and composition of fines in the development area. The PSDs were then classified into four distinct minor and major sand facies, ranging from medium to very coarse sand with different fines content. Further investigations have shown that current design is only suitable for a limited number of PSDs, while the overall PSD classes indicate requirement of wider slot aperture sizes. The results of the SRTs indicated that the flow performance of the screen is mainly controlled by the slot aperture. Choosing the optimized aperture size avoids unacceptable sanding even for the multiphase flow scenarios with gas. Results also indicated that by increasing the aperture size and application of the seamed slots for the studied formation, plugging could be mitigated. Finally, a detailed Finite Element Analysis (FEA) was conducted to compare the mechanical integrity of the current slotted liner design and the optimized design obtained from the experimental testing.

A comprehensive sand control design workflow for cold primary heavy oil production in horizontal wells is presented in this work. The current study is one of the first that investigates and compares conventional straight slotted liners with seamed slotted liners at larger scale for a field. Moreover, this study helps to better understand the effect of design parameters of seamed slotted liners on sand control, flow performance and mechanical strength.
Effect of Oil Production on the Price of Oil
Authors: Aguilera Roberto F. , Aguilera Roberto
Published: July 2020

The objective of this paper is to investigate the effect of oil production on the price of oil considering particularly the case of unconventional (tight and shale) reservoirs.

Five years ago, at LACPEC 2014 in Maracaibo, Venezuela, we presented an original paper and a methodology to investigate the price of oil. We stated in that paper that "with the vast global oil resource base and significant technological advances being implemented by the industry, oil prices could decrease in the future" (Aguilera and Aguilera, 2014). Given the good comparison between our 2014 LACPEC study and the actual oil pricing during the last 5 years, we use the same methodology for investigating possible ranges of oil prices in the future.

Our results stem from a successful match, using a Variable Shape Distribution (VSD) model, of the small and large variations of oil prices since 1861. Results are good, with a coefficient of determination (R2) larger than 0.98. We also match successfully oil consumption rates from 1861 to 2019 using a Global Energy Market (GEM) Model. The combination of the VSD and GEM, and our investigation on availability of oil resources, lead to the conclusion that our 2014 statement at LACPEC in Maracaibo remains current: "with the vast global oil resource base and the significant technological advances being implemented by the industry, oil prices could decrease in the future". Our methodology further indicates that, barring an unforeseen global disruptive event, oil prices will remain depressed for the foreseeable future. This supports the findings of Aguilera and Radetzki (2015) who in their book, The Price of Oil, forecast oil prices between $40 and $60 by 2035. This contrasts with the work of authoritative energy forecasting agencies who project rising prices in the coming decades. Also, as opposed to some oil companies, particularly some of the European organizations, that see the peak oil demand coming soon enough, e.g. the mid-2020s, our research indicates that it is unlikely that oil demand will peak in the coming decades.

The uniqueness of our forecasting methods for the oil price and global oil consumption is that our methods have remained unchanged since their creation (Aguilera and Aguilera, 2007) and yet they continue to generate reasonable results. This contrasts with methods of other organizations and commentators that change their forecasts repeatedly.
Novel Analytical Approach for Polymer Injectivity Tests in Los Perales Field, Argentina
Authors: Cocco Mauro Daniel , Volzone Darío , Fuzul Eduardo , Katz Román , Perez Diego Gastón
Published: July 2020

Polymer admission studies at the objective reservoir layers are one of the first critical experimental tests prior to field injection. Pressure build-up in the injector well is measured during a short period of time and its projections are used to select maximum polymer injection flow-rate and pumps. Complementary, polymer stability must be monitored during the injectivity test to reduce viscosity fluctuations, and a flowback test will finally validate the whole process asserting absence of polymer degradation at reservoir conditions.

In Los Perales three wells were tested for HPAM polymer-flood. Near-wellbore pressure transient analysis is not accurately resolved by numerical simulators, so an analytical pressure build-up model considering polymer non-Newtonian rheology was developed to make projections adjusted to measured data. Polymer thermal variations and degradation mechanisms (mechanical and chemical) in surface facilities have been also studied (Katz Marquez, 2019). Then, a flowback test in one of the wells was performed to check for polymer degradation and validate the whole assay.

During the injectivity test, measurements and further estimations, derived from the ad-hoc analytical model, showed that the objective polymer doses and injection flow-rate will be admitted by the reservoir. On the other hand, chemical degrading processes rise as challenging problems to deal with. Oxygen combined with hydrogen sulfide was found to be the main responsible for chemical degradation. One of the steps in the process of solving this issue was to develop an equation which allows us to predict viscosity behavior considering these effects. Hence, several ways to reduce degradation were implemented. Finally, the flowback test in one well validated the assay showing that combined degradation (mechanical and chemical) did not reduce active polymer concentration in more than 25%. In order to make degradation-free viscosity measurements, an ad-hoc 3D-printed anaerobic chamber for the viscometer was developed and successfully implemented.

The present work serves as a guideline to perform injectivity test, estimate well pressure build-up, deal with chemical and mechanical degradation processes and validate the process through a flowback test a further data analysis.
Well Cementing in an Abnormal Pressure Zone of the Talara Basin: Overcoming Engineering Challenges
Authors: Pingo Abraham , Vera Christian , Soriano Victor Hugo , Villanueva Jaime , Ahmed Ramadan , Hilario Poma Juan , Paredes José Luis
Published: July 2020

The Talara Basin in Perú is a mature oil field where production is extremely marginal, and well-construction designs are tailored to this condition to optimize well costs. However, one well recently drilled in this area was identified with the original reservoir pressure, and the well design was not based on this pressure. As a result, drilling issues such as fluid loss and lost circulation were carefully monitored while trying to control reservoir pressure in a long open-hole section. The challenges faced while cementing a high-pressure zone with controlled fluid losses and achieving well objectives in terms of safety, reliability, and lifetime zonal isolation of the well are discussed.

At the planning stage, a mud density of 13 lbm/gal was considered adequate to control downhole pressure (overbalanced); however, before reaching total depth, signs of high pressure were observed while drilling through a low-permeability formation. Mud density was significantly increased to control the well while monitoring the fluid return. When the mud weight reached 15.5 lbm/gal, losses were reported. Finally, the well was stabilized at 15.8 lbm/gal using different lost circulation pills. This event complicated the cementing operation because it substantially increased the necessary slurry density (16.1-lbm/gal lead and 17-lbm/gal tail). Nevertheless, proper cementing design and effective slurry placement using conventional techniques resulted in successful cementing operation with full cement return to the surface.

High-density cement slurries were successfully mixed and pumped regardless of their highly viscous property. The cementing unit and personnel were able to manage this vital operation without facing major problems. Before bumping the plug, circulating pressure was close to the theoretical value, confirming that the cement slurry column was as per the design without noticeable losses into the formation. Full cement returns confirmed a successful cement placement. Final circulating pressure was 2,370 psi, and it increased to 2,900 psi when the plug was bumped. The cement evaluation log obtained after 24 hours indicated good bonding, effective mud displacement, and a successful cement operation. The well was then fractured and put on production. Neither corrective work nor a well-integrity remediation operation was necessary.

Drilling the abnormally pressurized well was extremely challenging because of unexpected high pressure and associated problems, including working with high-density slurries and using various fluid additives to achieve adequate zonal isolation for future stimulation works. Techniques involved and experiences gained while undertaking this considerably challenging project are discussed in this article.