bluuebunny/crossref_metadata_2025 huggingface dataset:
EFEKTIVITAS PENGAWETAN DENGAN TEKNIK INFUS DAN BANDAGE PADA POHON BALAM TERHADAP SERANGAN RAYAP KAYU KERING
Authors: Sribudiani Evi , Rini Satiti Esti , Muliastuty Arsyad Wa Ode , Somadona Sonia , Damayanti Ratih , Djarwanto Djarwanto , Sulaeman Rudianda , Yusuf Sulaeman , Amin Yusup , Tarmadi Didi , Pramasari Dwi Ajias , Syafrinal Syafrinal
Published: December 2021

Saat ini keberadaan kayu jenis meranti merah, kulim dan mersawa sebagai bahan baku pembuat jalur di Kabupaten Kuansing Provinsi Riau semakin langka, sedangkan kebutuhan kayu sebagai bahan pembuat jalur semakin tinggi. Oleh sebab itu diperlukan pemilihan jenis kayu alternatif yang memiliki persamaan sifat kuat dan awet dengan kayu jenis meranti merah, kulim, dan mersawa agar dapat memenuhi spesifikasi pembuatan jalur. Penelitian ini bertujuan mempelajari efektivitas pengawetan kayu balam dengan teknik infus dan bandage terhadap rayap kayu kering. Balam (Macaranga conifera Muell. Agr.) dipilih sebagai kayu alternatif untuk membuat jalur karena saat ini masih banyak ditemukan namun belum banyak dipakai untuk pembuatan jalur. Hasil pengamatan di lapangan menunjukkan bahwa jalur yang disimpan di darat mendapatkan serangan rayap kayu kering, sehingga diperlukan pengawetan jalur agar tidak terserang organisme perusak kayu (OPK) khususnya rayap kayu kering. Pengawetan pohon berdiri dengan senyawa boron komplek dengan teknik infus dan bandage dipilih untuk meningkatkan kelas keawetan kayu balam. Pengujian ketahanan kayu terhadap serangan rayap kayu kering dilakukan sesuai metode SNI 7207-2014. Data diolah dengan menggunakan rancangan faktorial acak lengkap. Hasil analisis menunjukkan bahwa pengawetan dengan teknik infus dan bandage berbeda nyata terhadap pengurangan berat dan mortalitas rayap. Pengamatan derajat serangan secara visual pada kontrol dan teknik infus yaitu 40 (tahan) yang nilainya lebih rendah dibandingkan teknik bandage 70 (sedang). Mortalitas pada teknik infus lebih tertinggi yaitu 90,67% dibandingkan kontrol 86,08% dan bandage 61,75%. Teknik pengawetan dengan teknik infus menunjukkan kandungan boron yang lebih tinggi dibandingkan dengan teknik bandage.
The Mach's Principle and Large-scale Modification of Newtonian Gravitation as Alternative Approach to Cold Dark Matter and Dark Energy
Authors: Falcon Nelson
Published: December 2021

We take a heterodox approach to the ΛFRW Cosmology starting from the modification of Newtonian gravity by explicitly incorporating Mach's Principle through an additional term a great scale in the gravitation. The results show that at the after of the matter-radiation decoupling, the distribution of matter at scales greater than 10Mpc contributes with an inverse Yukawa-like field, which verifies the observations: resulting null in the inner solar system, weakly attractive in ranges of interstellar comoving distances, very attractive in comoving distance ranges comparable to the clusters of galaxies, and repulsive in cosmic scales. This additional term explains dark energy, removes the incompatibility between the density of matter and the flatness of the universe; and also allows the theoretical deduction of the Hubble-Lemaitre Law. Additionally, Birkhoff Theorem, Virial Theorem, the missing mass of Zwicky, the BAO, gravitational redshift are discussed. It is concluded that the dark energy and the missing mass can be approached with the usual physics if a classical, large-scale modification of the Inverse Square Law.
Quantum Computing for Dealing with Inaccurate Knowledge using the Certainty Factors Model
Authors: Moret-Bonillo Vicente , Magaz-Romero Samuel , Mosqueira-Rey Eduardo
Published: December 2021

In this paper we try to demonstrate that the classical model of certainty factos for dealing with innacurate knowledge can be efficiently implemented in a quantum environment. For this, we assume that certainty factors are strongly correlated with the quantum probability. We first explore the certainty factors approach for inexact reasoning from a classical point of view. Next, we introduce some basic aspects of quantum computing, and we pay special attention to quantum rule-based systems. We then build a use case: an inferential network to be implemented in both, the classical approach and the corresponding quantum circuit. Both implementations have been used to compare the behavior of the classical and the quantum approaches when confronted with the same hypothetical case. We analyze three different situations: (1) Only Imprecision (which refers to inaccuracy in declarative knowledge or facts) is present in the use case, (2) Only Uncertainty (which refers to inaccuracy in procedural knowledge or rules) is present in the use case, and (3) Both Imprecision and Uncertainty are present in the use case. Finally, we analyze the results to reach a conclusion about the eventually intrinsic probabilistic nature of the certainty factors model and to pave the way for future quantum implementations of this method for handling inaccurate knowledge.
Validation of Recent Altimeter Missions at Non-dedicated Tide Gauge Stations in the Southeastern North Sea
Authors: Esselborn Saskia , Schöne Tilo , Illigner Julia , Weiß Robert , Artz Thomas , Huang Xinge
Published: December 2021

Consistent calibration and monitoring is a basic prerequisite for providing reliable time series of global and regional sea level variations from altimetry. The precision of sea level measurements and regional biases for six altimeter missions (Jason-1/2/3, Envisat, Saral, Sentinel-3A) is assessed at eleven GNSS-controlled tide gauge stations in the German Bight (SE North Sea) for the period 2002 to 2019. The gauges are partly located at the open water, partly at the coast close to mudflats. The altimetry is extracted at virtual stations with distances from 2 to 24 km from the gauges. The processing is optimized for the region and adjusted for the comparison with instantaneous tide gauges readings. An empirical correction is developed to account for mean height gradients and slight differences of the tidal dynamics between gauge and altimetry which improves the agreement between the two data sets by 15-75%. The precision of the altimeters is depending on location and mission and is shown to be at least 1.8 to 3.7 cm based on an assumed precision of 2 cm for the gauges. The accuracy of the regional mission biases is strongly dependent on the mean sea surface heights near the stations. The most consistent biases are obtained based on the CLS2011 model with mission dependent accuracies from 1.3 to 3.4 cm. Hence, the GNSS-controlled tide gauges operated operationally by WSV might complement the calibration and monitoring activities at dedicated CalVal stations.
A Sustainable Approach to Geomatic Methods in Ravine Monitoring and Associated Natural Disaster Prevention
Authors: Naș Sanda , Ciurean Oana Manuela , Bondrea Mircea V. , Radulescu Virgil Mihai
Published: December 2021

This paper presents the monitoring of an extremely eroding phenomenon (ravine) near Ciurila, Cluj County, Romania, using UAV (Unmanned Aerial Vehicle) and GNSS (Global Navigation Satellite System) technologies, taking into account the objectives of SDG 15 of the UN resolution, which refers to life on earth. In this sense, the results of a monitoring through sustainable and non-invasive technologies are presented, follo-wing three cycles of observations, carried out between June 2019 and April 2021.The paper aims to present the advantages and limitations of such a study , as well as the importance of monitoring erosion phenomena (in this case, ravines) for the ecosystem, but also for the nearby inhabitants. Software and technologies are used that allow the automatic calculation of the volume of the ravine and the displacements between the different measurement cycles, which allows obtaining objective conclusions and pro-posing further measures.
How Does Contraceptive Use Affect Women’s Sexuality? A Novel Look at Sexual Acceptability
Authors: Caruso Salvatore , Palermo Gaia , Caruso Giuseppe , Rapisarda Agnese Maria Chiara
Published: December 2021

Among the components of a healthy life, sexuality is an essential part, contributing not only to psychophysical well-being, but also to the social well-being of women and, consequently to their quality of life. A poorly investigated standpoint is the acceptability of a contraceptive method, not only in terms of tolerability and metabolic neutrality, but also concerning the impact that it can have on sexual life. In this context, we will provide an overview of the different methods of contraception and their effects on female sexuality from the biological changes, to organic, social, and psychological factors, which can all shape sexuality.A MEDLINE/PUBMED review of the literature between 2010 and 2021 was conducted using the following key words/phrases: hormonal contraception, contraceptives, female sexual function, libido, sexual arousal and desire, and sexual pain. Recent studies have supported the effects of contraceptives on women’s sexuality, describing a variety of positive and negative events on several domains of the sexual function (desire, arous-al, orgasm, pain, enjoyment). However, satisfaction with sexual activity depends on factors that extend beyond sexual functioning alone. A more holistic approach is needed to better under-stand the multitude of factors linked to women’s sexuality and contraception. Contraceptive counselling must necessarily consider these important elements since they are closely related to good compliance.
“Her Şey Aslına Döner”: Bayrâmî-Melâmî Şâir Hüseyin Lâmekânî’nin İki Tasavvufî Risâlesi
Authors: SOFUOĞLU Nesrin
Published: December 2021

Bayrâmî-Melâmî şeyhi ve mutasavvıf şair Hüseyin Lâmekânî 16. yy. sonları ile 17. yy. başlarında yaşamıştır. Doğum tarihi bilinmeyen Lâmekânî’nin vefâtına düşürülen tarih beyitlerine göre ölüm tarihi 1035/1625’dir. Lâmekânî mahlası ile yazdığı Dîvân ve Esrâr-nâme çevirisi gibi manzum eserlerin yanı sıra tasavvufî risâleler ve mektuplar kaleme almıştır. Lâmekânî’nin ayrıca manzum ve mensur karışık olarak yazılmış “Küllü şey’in yerci‘u ilâ aslihî” hadîsini şerh eden risâleleri de bulunmaktadır. Risâlenin bir nüshası şairin Dîvân’ının bulunduğu mecmua içerisinde yer almaktadır. Diğer risâle ise Ankara Milli Kütüphanedeki bir yazma eserde Risâle-i Hüseyin Lâmekânî ismiyle kayıtlıdır. Bu risâlelerde vahdet-i vücûd anlayışı doğrultusunda Tanrı, âlem ve varlık konularına dînî ve tasavvufî deliller ışığında açıklık getirilmektedir.

Bu çalışmada Hüseyin Lâmekânî’nin Risâle fî Külli Şey’in Yerci‘u ilâ Aslihî adlı risâlelerinin metin neşri, sadeleştirmesi yapılmıştır. Ayrıca eserler bağlamında Lâmekânî’nin vahdet-i vücûd anlayışı ele alınmıştır.
Şeyh Bekir Sıdkı Visâlî Tarafından Bestelenmiş Mûsiki Eserleri
Authors: YILMAZ Muhammed Cahid
Published: December 2021

Tasavvuf, amacına ulaşmak için çeşitli araçlardan yararlandığı gibi, güzel sanatlardan da istifade etmiştir. Bu bağlamda tasavvuf ile mûsiki arasındaki güçlü ilişkinin sonucu olarak, Türk mûsikisi tarihi boyunca tarikat çevrelerinden birçok mûsikişinas yetişmiş, tekkeler ve dergâhlar mûsikinin icra edildiği ortamların en önemlilerinden olmuştur. Tekke ortamının ihtiyaç ve alışkanlıkları doğrultusunda, her tarikatın kendi erkânı ve uygulamaları ile şekillenen bir tekke mûsikisi ortaya çıkmıştır. Şeyh Abdurrahman Sâmî Saruhânî’nin halifesi olarak 20. yüzyılda İzmir ve civarı illerde irşad faaliyetlerinde bulunmuş olan Halvetî-Uşşâkî şeyhi Bekir Sıdkı Visâlî, çeşitli alanlarda eserler vermiş bir mutasavvıftır. Şeyh Bekir Sıdkı Visâlî, irşad faaliyetlerini yürütürken, şiir ve sohbet gibi vasıtaların yanında mûsikiye de yer vermiş, çeşitli makamlarda ve formlarda dinî eserler bestelemiştir. Bu çalışma, Şeyh Bekir Sıdkı Visâlî’nin mûsikişinas yönünü tanıtmayı; şimdiye kadar yayımlanmamış olan, çeşitli form ve usûllerde bestelediği ve tarafımızdan tespit edilebilmiş on adet dinî mûsiki eserinin yanı sıra bestelediği eserlerin icra zaman ve mekânları ile bilgileri ilim ve sanat camiasına kazandırmayı hedeflemektedir.
İslamcı Bir Düşünür, Said Halim Paşa’nın Batılılaşmaya Bakışı
Authors: TÜRKYILMAZ Hilmi
Published: December 2021

Said Halim Paşa (1864-1921), Osmanlı’nın son dönemlerinde yaşamış, sadrazamlık da dahil olmak üzere bir çok devlet görevinde bulunmuş önemli şahsiyetlerden biridir. Paşa’yı önemli kılan unsur, uzun yıllar devlet görevinde bulunduğu halde siyasetten ziyade toplumsal sorunlarla ilgilenmesidir. Onun görev yaptığı zamanlar devletin en buhranlı olduğu, toplumun en çalkantılı olduğu bir döneme tekabül etmektedir. Batı’nın, Osmanlı toplumunu her alanda kıskaca aldığı bu dönemde toplumsal sorunları kendine dert edinmiş, Batı karşısında “nasıl kalkınabiliriz” sorusuna cevap aramıştır. Özelde Osmanlı toplumunun genelde ise İslam dünyasının sorunlarını tespit edip çözümler üretmeye çalışmıştır. Bu amaçla Batı’yı ve İslam Dünyası’nı çok iyi bilen Said Halim, Osmanlı toplumunu derin bir tahlile tabi tutmuştur. Müslüman toplumların, Batı karşısında nasıl bir tavır alması gerektiği ve nasıl bir modernleşme yöntemi takip etmesi gerektiği üzerinde fikirlerini ortaya koymuştur. Yaptığı tahliller ve ürettiği çözümlerin özgün olması sebebiyle Said Halim Paşa, aynı konularda fikir üreten devrindeki diğer düşünürlerden ayrılmaktadır.
Radiographic Appearance of Cosmetic Gluteal Injections in a Patient With Proximal Hamstring Tear
Authors: Holden Paige , Kanski Gregory , Coyner Katherine J.
Published: December 2021

Case:

A 45-year-old woman presented 6 months after a right proximal hamstring repair with worsening pain over her surgical site. Anterior-posterior pelvis x-rays revealed bilateral soft-tissue densities around the hips. Extensive workup revealed no medical basis for the radiographic appearance. It was discovered that the patient's cosmetic gluteal injections were, in fact, the cause. Follow-up x-rays revealed near-complete resolution of the densities 8 months later.

Conclusions:

We present this case to highlight the need to consider cosmetic injections as a potential cause of abnormal radiographic soft-tissue densities in the absence of other clear medical explanations in patients who present with musculoskeletal complaints.
Prospective Risk Factors of Toxoplasmosis Seropositivity in Pregnant Women: The Fundamental Role of Community Healthcare Education
Authors: Eltayeb Lienda , Hamad Nasir , Babiker Abeer
Published: December 2021

Background: The present study conducted a survey on awareness of toxoplasmosis infection, with an emphasis on risk factors, and an assessment of toxoplasmosis prevalence in pregnant women in Al-Kharj province of KSA. Methods and Results: A cross-sectional study with a qualitative approach was carried out from August 2018 to February 2019. The study recruited all pregnant women who attended maternity and children’s outpatient clinics. The non-probability sampling approach was used to select 345 blood samples from study subjects. T. gondii-specific IgG and IgM antibodies were identified using ELISA. Each participant enrolled in the study was provided with a validated questionnaire to fill out by an assistant of the laboratory technician or an antenatal care nurse. In addition to socio-demographic data, simple closed-ended questions about established risk factors for T. gondii exposure were included in the questionnaire items, and answers were listed in a three-point Likert scale (agree, disagree, I am not sure). The overall prevalence of T. gondii-specific antibodies among study subjects was 12.75%; 29(8.40%) women were positive for IgG only, 9(2.6%) - for IgM, and 6(1.7%) - for both IgG and IgM antibodies. About 41.4% of participants were in the first trimester of pregnancy; among them 31(9%) were positive for T. gondii antibodies. 82.8% of pregnant women had chronic infection in the first trimester, while 44.4% of those women also had an acute infection. The number of respondents to the questionnaire was 345 participants with a response rate of about 100%. It is important to note that 81.5% of women were unaware that toxoplasmosis is dangerous, and two-thirds of them didn't know the dangerous complications for the fetus and newborn. Conclusion: The current study concludes that there is a low prevalence of toxoplasmosis among Saudi pregnant women in Al-Kharj province. A general program must be implemented to increase population awareness, especially among the at-risk populations.
Association of the IRF6 rs2235371 and rs861019 Polymorphisms with Non-Syndromic Cleft Lip with or without Cleft Palate in the Yakut Population
Authors: Pavlova Nadezhda , Diakonova Aleksandra , Alekseev Vladislav , Mironova Lyubov , Dodokhov Vladimir , Kurtanov Khariton , Ushnitsky Innokenty
Published: December 2021

Background: Non-syndromic cleft lip with or without cleft palate (NSCL/P) is one of the most common birth defects. NSCL/P can be broadly divided into cleft lip only (CLO), cleft palate only (CPO), and cleft lip with cleft palate (CLP) based on clinical presentation. The aim of this study was to investigate the relationship between the IRF6 gene polymorphisms and non-syndromic cleft lip with or without cleft palate (NSCL/P) in the Yakut population. Methods and Results: In 23 OFC patients and 58 unrelated control subjects from the Yakut population, we tested two SNPs (rs2235371 and rs861019) with a minor allele frequency of more than 5% in the candidate gene IRF6. We found that the SNP marker rs861019 showed significant differences in allele frequencies (OR=2.07, 95%CI: 1.01–4.23, P=0.04) between the NSCL/P patients and the comparison group. Analysis of allele frequencies for rs861019 SNP in subgroups showed that there was a difference in the frequency between CLP and control (OR=5, 95% CI: 1.61-15.53, P=0.11); however, this result was not significant. Genotype analysis showed significant differences in patients from the CLP subgroup in comparison with controls for homozygous (AA compared with GG) (OR=9.00, 95% CI: 1.03–78.58, P=0.03), heterozygous (GA compared with GG) (OR=5.50, 95% CI: 1.05-28.75, P=0.04,), recessive (GG compared with GA + AA) (OR=6.67, 95% CI: 1.61-27.58; RR=4.78, 95% CI: 1.42–16.10, P=0.008,) and co-dominant (GG compared with GA, compared with AA) (P=0.02) inheritance models. Diplotype analysis showed that the NSCL/P group was more likely to have the [CC]-[GG] diplotype than the comparison group. This diplotype carries the risk GG genotype (rs861019) (30.4%) and does not carry the risk T allele(rs2235371). In the CLP subgroup, two diplotypes ([CT]-[GG] and [CC]-[GG]) were found more often than in the comparison group. Both diplotypes carry the risk GG genotype(rs861019; 33.3%). In the CPO subgroup, the [CT]-[GG] diplotype was more common. In the CLO subgroup, only two diplotypes ([CC]-[GA] and [CC]-[GG]) were found, both of which were more common than in the comparison group (75% and 25%).. It is likely that these results for the CLO and CPO subgroups were influenced by the small size of both samples. Unlike the NSCL/P and CLP groups, in these samples, diplotypes with the homozygous genotype GG (rs861019) without the homozygous genotype TT (rs2235371) were more common. Diplotypes with a homozygous genotype of the TT risk allele were not found in the studied groups except for the comparison group, where the [TT]-[AA] diplotype was represented by a low frequency (0.17%). Conclusion: The present study provides strong statistical support (for the first time to our knowledge) that genetic variants of the IRF6 rs861019 SNP are associated with NSCL/P in Yakuts.
Effect of the p38 MAPK Inhibitor on the Expression of Metalloproteinases and Their Inhibitors during the Formation of Abdominal Adhesions
Authors: Shurygina Irina , Rodionova Lyubov , Ayushinova Natalia , Chepurnykh Elena , Trukhan Irina , Shurygin Michael
Published: December 2021

Background: The aim of this study was to assess the effect of blockade of the p38 mitogen-activated protein kinase (MAPK) on the expression of genes encoding metalloproteinases (MMPs) during the formation of adhesions in the abdominal cavity. Methods and Results: The experiments were carried out on male Wistar rats (n=75). The studies were carried out in two groups: Group 1 (control, n=35) – modelling the adhesive process; Group 2 (experimental, n=35) – modelling the adhesive process with intraperitoneal administration of Seroguard®—a prolonged form of the p38 MAPK inhibitor. The expression of the MMP1a, MMP2, MMP7, MMP9, and TIMP genes was assessed using real-time PCR. In the control group, overexpression of the MMP1a and MMP7 genes began from 6 hours after modeling the adhesive process, MMP9 – from Day 1, MMP2 – from Day 7 and persisted until the end of observation. With local blockade of p38 MAPK, the level of overexpression of genes encoding MMPs in the early stages was higher than in the control group (MMP1a – by Day 1; MMP7 – by 6 hours and Day 1, MMP9 – by 12 hours). From Day 3 to Day 14, the MMP1a and MMP7 expression in the experimental group was significantly lower than in the control group. Conclusion: The performed study demonstrated the involvement of different types of MMPs—collagenases (MMP1a), gelatinases (MMP2 and 9), matrilysins (MMP7)—in the rearrangement of the extracellular matrix during the process of adhesion formation in the abdominal cavity.
Evaluating Phase Blockages and Mobility Changes During Pressure Transient Analysis
Authors: Bellabiod Sofiane , Karacali Ozgur , Aris Abdelkader , Deghmoum Abdelhakim , Theuveny Bertrand
Published: December 2021

Pressure transient analysis (PTA) is a cogent methodology to evaluate dynamics of hydrocarbon reservoirs. Numerous analytical and numerical models have been developed to model various types of wellbore, reservoir, and boundary responses. However, the near-wellbore region remains to be perplexing in pressure transient analysis. In this paper we investigate the pressure transient behavior of phase blocking and mobility variations caused by fluid phase interactions or properties, such as viscous drag forces and surface tension at the near-wellbore region and their impact on pressure transient evaluation.

We have used real field examples to scrutinize relative effects of mobility variations in pressure transients. The impact of capillary number (Nc) acting on the near-wellbore region and its influence on pressure transient behavior and skin alteration were examined in detail. Several real field examples honoring actual reservoir rock special core analysis (SCAL) and fluid pressure/volume/temperature (PVT) properties have been studied. Actual field data discussed in this paper for PTA were captured during drill stem testing (DST) operations from various hydrocarbon reservoirs in the Berkine Basin of Algeria. PVT laboratory-measurement-based fluid properties were used in conjunction with tuned equation of state (EOS) models to ensure consistency between wells and reservoirs.

Pressure transient analysis of a gas condensate reservoir system can depict various mobility regions, especially while flowing below dew point pressure. In some cases, three-distinct-mobility regions can be identified as: a far-field zone with initial gas and condensate saturation; a mid-field zone with increased condensate saturation and lower gas relative permeability; and a near-wellbore zone with high Nc which increases gas relative permeability and mobility. These three-distinct-mobility regions form due to condensate dropping out and fluid interactions in the near wellbore. We demonstrate, with real-life field examples of the near-wellbore region, how the relative effects of viscous drag forces and surface tension forces acting across the liquid and gas interface can enable the reference fluid phase to regain its mobility. We further investigate the evaluation of skin factor in such circumstances and show how the existence of phase blocking and velocity stripping can cause over-estimation or under-estimation of skin factor.

We present a novel set of real field examples and relations between various zones in hydrocarbon reservoirs to avoid snags of misleading pressure transient interpretations and how composite models can be accurately used to represent complex cases. Field examples from Algerian hydrocarbon reservoirs are depicted. The findings could be easily applied for similar reservoirs in other parts of the globe to identify and model such intricate systems.
Well Integrity Leak Diagnostic Using Fiber-Optic Distributed Temperature Sensing and Production Logging
Authors: Abeling Joerg , Bartels Ulrich , Singh Kamaljeet , Dutta Shaktim , Agrawal Gaurav , Kumar Apoorva
Published: December 2021

Fiber optics has many applications in the oil and gas industry. In recent years, fiber optics has found usefulness in leak detection. The leaks can be efficiently identified using fiber-optic distributed temperature sensing measurement, thereby mitigating the health, safety, and environmental (HSE) risk associated with well integrity. Further, a production log can be used to gain more insight and finalize a way ahead to resolve well integrity issues.

An innovative solution-driven approach was defined, with fiber-optic distributed measurement playing a key role. Multiple leaks were suspected in the well completion, and a fiber-optic cable was run to identify possible areas of the leak path. After the fiber-optic data acquisition, a production log was recorded across selective depths to provide an insight on leak paths. After identifying leak depths, a definitive decision between tubular patching and production system overhaul was decided based on combined outputs of the fiber-optic acquisition and production log.

Results are presented for a well where multiple leaks were successfully identified using the novel operational approach. Further, operational time was reduced from 3 days (conventional slickline memory or e-line logging performed during daylight operation) to 1 day (a combination of fiber-optic distributed temperature sensing and production log in a single run). The diagnosis of production system issues was completed in one shut-in and one flowing condition, thereby reducing the risk of HSE exposure with multiple flowing conditions (to simulate the leak while the conventional production logging tool is moved to different depths in the well). Additional insight on leak quantification was confirmed from the production log data, where one leak was noted at the tubing collar while the other leak was noted a few meters above the tubing collar. This observation was substantial in deciding whether to proceed with tubing patch or replace the entire production tubing.

The novel operational approach affirms fiber-optic distributed temperature measurement's versatility in solving critical issues of operation time and reducing HSE exposure while delivering decisive information on production system issues. The paper serves as a staging area for other applications of similar nature to unlock even wider horizons for distributed temperature sensing measurement.
Informed Decisions Guided by GeoMechanics to Improve Drilling Performance: A Case Study from Onshore Field, Abu Dhabi; UAE
Authors: Benmamar Salim , AL Arfi Saif Al Arfi , Perumalla Satya , Salem Gamal , Baruno Agung , Saha Sankhajit , Bhatt Pranjal
Published: December 2021

ADNOC (Abu Dhabi National Oil Company) recently drilled some wells in Onshore Abu Dhabi (Field-A) and encountered consistent hole instability from Umm Er Radhuma (UER) to Simsima. Thus, a GeoMechanical review was proposed to investigate the root causes, if any, and recommend possible remedies for the upcoming drilling campaign.

While detailed drilling event analysis allowed to investigate the correlation between the mud weight program and well trajectory, borehole image log analysis and geological understanding from nearby fields indicated the possible role of structural and lithological features on hole instability. Integration of drilling engineering data and regional geological knowledge helped to narrow down the possible causes of drilling challenges. Sedimentalogical review of Image logs have established some correlation between rock types and hole instability events.

Drilling experience shows there is very narrow margin for loss and/or gain to occur. There is regional geological evidence of the presence of a wide range of vuggy structures, as well as natural fractures and/or faults. These features tend to make Simsima formation heterogeneous in terms of permeability and more prone to losses. Since most fractures are parallel to SHmax direction and well was drilled towards Shmin direction, there are greater chances of encountering faults and/or fractures, which would be critically-stressed and lead to loss and/or gain situations. Geomechanical parameters helped highlight the magnitudes and orientations of principal stresses. Observations of several tight hole and stuck pipe events while tripping from Radhuma and UERB shale to Simsima seem to indicate mud weight used was insufficient. Role of multiple failure mechanisms was identified, and relevant solutions were recommended as well as implemented to achieve the drilling success.

The case study presented here emphasizes how different carbonate textures and the presence and orientation of natural fractures and/or faults within Simsima formation can impact hole instability with respect to wellbore trajectory. Proactive implementation of recommendations from this analysis on well planning and fluid design resulted in improvement of drilling performance and reduction of non-productive time in new wells.
Utilizing NMR Workflow to Optimize Power Water Injector Placement in the Presence of Tar Barriers
Authors: Hursan Gabor , Sahhaf Mohammed , Amairi Wala’a
Published: December 2021

The objective of this work is to optimize the placement of horizontal power water injector (PWI) wells in stratified heterogeneous carbonate reservoir with tar barriers. The key to successful reservoir navigation is a reliable real-time petrophysical analysis that resolves rock quality variations and differentiates tar barriers from lighter hydrocarbon intervals. An integrated workflow has been generated based on logging-while drilling (LWD) triple combo and Nuclear Magnetic Resonance (NMR) logging data for fluid identification, tar characterization and permeability prediction.

The workflow has three steps; it starts with the determination of total porosity using density and neutron logs, the calculation of water-filled porosity from resistivity measurements and an additional partitioning of porosity into bound and free fluid volumes using the NMR data. Second, the total and water-filled porosity, the NMR bound fluid and NMR total porosity are used as inputs in a hydrocarbon compositional and viscosity analysis of hydrocarbon-bearing zones for the recognition of tar-bearing and lighter hydrocarbon intervals. Third, in the lighter hydrocarbon intervals, NMR logs are further analyzed using a multi-cutoff spectral analysis to identify microporous and macroporous zones and to calculate the NMR mobility index. The ideal geosteering targets are highly macroporous rocks containing no heavy hydrocarbons. In horizontal wells, the method is validated using formation pressure while drilling (FPWD) measurements.

The procedure has been utilized in several wells. The original well path of the first injector was planned to maintain a safe distance above an anticipated tar-bearing zone. Utilizing the new real-time viscosity evaluation, the well was steered closer to the tar zone several feet below the original plan, setting an improved well placement protocol for subsequent injectors. In the water- or lighter hydrocarbon-bearing zones, spectral analysis of NMR logs clearly accentuated micro- and macroporous carbonate intervals. The correlation between pore size and rock quality has been corroborated by FPWD mobility measurements. In one well, an extremely slow NMR relaxation may indicate wettability alteration in a macroporous interval.

An integrated real-time evaluation of porosity, fluid saturation, hydrocarbon viscosity and pore size has enhanced well placement in a heterogeneous carbonate formation where tar barriers are also present. The approach increased well performance and substantially improved reservoir understanding.
A Novel Corrosion Monitoring and Prediction System Utilizing Advanced Artificial Intelligence
Authors: Katterbauer Klemens , Dokhon Waleed , Aulia Fahmi , Fahmi Mohanad
Published: December 2021

Corrosion in pipes is a major challenge for the oil and gas industry as the metal loss of the pipe, as well as solid buildup in the pipe, may lead to an impediment of flow assurance or may lead to hindering well performance. Therefore, managing well integrity by stringent monitoring and predicting corrosion of the well is quintessential for maximizing the productive life of the wells and minimizing the risk of well control issues, which subsequently minimizing cost related to corrosion log allocation and workovers.

We present a novel supervised learning method for a corrosion monitoring and prediction system in real time. The system analyzes in real time various parameters of major causes of corrosion such as salt water, hydrogen sulfide, CO2, well age, fluid rate, metal losses, and other parameters. The data are preprocessed with a filter to remove outliers and inconsistencies in the data. The filter cross-correlates the various parameters to determine the input weights for the deep learning classification techniques. The wells are classified in terms of their need for a workover, then by the framework based on the data, utilizing a two-dimensional segmentation approach for the severity as well as risk for each well.

The framework was trialed on a probabilistically determined large dataset of a group of wells with an assumed metal loss. The framework was first trained on the training dataset, and then subsequently evaluated on a different test well set. The training results were robust with a strong ability to estimate metal losses and corrosion classification. Segmentation on the test wells outlined strong segmentation capabilities, while facing challenges in the segmentation when the quantified risk for a well is medium.

The novel framework presents a data-driven approach to the fast and efficient characterization of wells as potential candidates for corrosion logs and workover. The framework can be easily expanded with new well data for improving classification.
Geology-Driven EUR Forecasting in Unconventional Fields
Authors: Temizel Cenk , Canbaz Celal Hakan , Alsaheib Hasanain , Yanidis Kirill , Balaji Karthik , Alsulaiman Nouf , Basri Mustafa , Jama Nayif
Published: December 2021

EUR (Estimated Ultimate Recovery) forecasting in unconventional fields has been a tough process sourced by its physics involved in the production mechanism of such systems which makes it hard to model or forecast. Machine learning (ML) based EUR prediction becomes very challenging because of the operational issues and the quality of the data in historical production. Geology-driven EUR forecasting, once established, offers EUR forecasting solutions that is not affected by operational issues such as shut-ins. This study illustrates the overall methodology in intelligent fields with real-time data flow and model update that enables optimization of well placement in addition to EUR forecasting for individual wells.

A synthetic but realistic model which demonstrates the physics is utilized to generate input data for training the ML model where the spatially-distributed geological parameters including but not limited to porosity, permeability, saturation have been used to describe the production values and ultimately the EUR. The completion is given where the formation characteristics vary in the field that lead to location-dependent production performance leading to well placement optimization based on EUR forecasting from the geological parameters. The algorithm not only predicts the EUR of an individual well and makes decision for the optimum well locations. As the training model includes data of interfering wells, the model is capable of capturing the pattern in the well interference.

Even though a synthetic but realistic reservoir model is constructed to generate the data for the aim of assisting the ML model, in practice, it is not an easy task to (1) obtain the input parameters to build a robust reservoir simulation model and (2) understanding and modeling of physics of fluid flow and production in unconventionals is a complex and time-consuming task to build real models. Thus, data-driven approaches like this help to speed up reservoir management and development decisions with reasonable approximations compared to numerical models and solutions. Application of machine learning in intelligent fields is also explained where the models are dynamically-updated and trained with the new data.

Geology-driven EUR forecasting has been applied and relatively-new in the industry. In. this study, we are extending it to optimize well placement in intelligent fields in unconventionals beyond other existing studies in the literature.
Outside the Box: Innovative Application of Diversion as a Replacement for Bridge Plug
Authors: Chang Hong , Yi De Qiang , Lv Yang , Zhao Ming , Cao Peng Liang , Zhang Lin , Hou Rui , Di Yi Liang , Chen Jie , Zhang Lu , Li Hao Yan , Fu Yun Long , Liu Yuan , Wang Wei Kan
Published: December 2021

Effective stage-to-stage isolation is typically accomplished by setting a bridge plug in a properly cemented casing between stages. This isolation plays a vital role in a horizontal well multistage fracturing completion. Failure of isolation not only impacts the well productivity but also wastes fracturing materials.

The challenges isolation failure poses for stimulation effectiveness include both detection and remediation. First, there has been historically no reliable and cost-effective solution to detect stage-to-stage isolation onsite. One may only start to realize this problem when inconsistent production is observed. Second, existing remedial actions are seldom satisfying in case of an isolation failure. Most commonly, a new plug is set to replace the failed one. However, because the perforation clusters of an unstimulated stage may create irregularities in well inside diameter (ID) (e.g., casing deformation or burr), there is a risk that the plug will be damaged or become stuck when it passes the perforation area. Also, when the plug passes a perforation cluster, the perforations start to take in the pump-down fluid, which can increase the difficulty of the pump-down job.

A novel remedial action uses high-frequency pressure monitoring (HFPM) and diversion to solve both challenges. The stage isolation integrity is evaluated in quasi-real time by analyzing the water hammer after the pump shutdown. In the case of a plug failure, large-particle fracture diversion materials and techniques can establish temporary wellbore isolation through a quick and simple delivery process. To close the cycle, the effect of the diversion can be evaluated by HFPM, which can reveal the fluid entry point of the treatment fluid after diversion.

The technique was applied to two cases in Ordos basin in which wellbore isolation failure interrupted the operation. The problem identification, development of the solution workflow, and observation from treatment analysis are discussed. In both cases, the stage-to-stage isolation was recovered, and the drilled sand body was successfully stimulated without involving costly and time-consuming well intervention. The stimulation operation of the entire well was successfully resumed in a timely manner.
Identification of Micro Fractures in Cretaceous Bioclastic Limestone in Iraq and Its Influence on Development of Reservoirs
Authors: Wang Genjiu , Hu Dandan , Li Qianyao
Published: December 2021

It is generally believed that Cretaceous bioclastic limestone in Mesopotamia basin in central and southern Iraq is a typical porous reservoir with weak fracture development. Therefore, previous studies on the fracture of this kind of reservoir are rare. As a common seepage channel in carbonate rock, fracture has an important influence on single well productivity and waterflooding development of carbonate reservoir.

Based on seismic, core and production data, this study analyzes the development characteristics of fractures from various aspects, and discusses the influence of fractures on water injection development of reservoirs. Through special processing of seismic data, it is found that there are a lot of micro fractures in Cretaceous bioclastic limestone reservoir. Most of these micro fractures are filled fractures without conductivity under the original reservoir conditions. However, with the further development of the reservoir, the reservoir pressure, oil-water movement, water injection and other conditions have changed, resulting in the original reservoir conditions of micro fractures with conductivity. The water cut of many production wells in the high part of reservoir rises sharply. In order to describe the three-dimensional spatial distribution of fractures, the core data is used to verify the seismic fracture distribution data volume. After the verification effect is satisfied, the three-dimensional fracture data volume is transformed into the geological model to establish the permeability field including fracture characteristics.

The results of numerical simulation show that water mainly flows into the reservoir through high angle micro fractures. Fractures are identified by seismic and fracture model is established to effectively recognize the influence of micro fractures on water injection development in reservoir development process, which provides important guidance for oilfield development of Cretaceous bioclastic limestone reservoir in the central and southern Iraq fields.
Development of Machine Learning Based Propped Fracture Conductivity Correlations in Shale Formations
Authors: Desouky Mahmoud , Tariq Zeeshan , Al jawad Murtada , Alhoori Hamed , Mahmoud Mohamed , Abdulraheem Abdulazeez
Published: December 2021

Propped hydraulic fracturing is a stimulation technique used in tight formations to create conductive fractures. To predict the fractured well productivity, the conductivity of those propped fractures should be estimated. It is common to measure the conductivity of propped fractures in the laboratory under controlled conditions. Nonetheless, it is costly and time-consuming which encouraged developing many empirical and analytical propped fracture conductivity models. Previous empirical models, however, were based on limited datasets producing questionable correlations. We propose herein new empirical models based on an extensive data set utilizing machine learning (ML) methods.

In this study, an artificial neural network (ANN) was utilized. A dataset comprised of 351 data points of propped hydraulic fracture experiments on different shale types with different mineralogy under various confining stresses was collected and studied. Several statistical and data science approaches such as box and whisker plots, correlation crossplots, and Z-score techniques were used to remove the outliers and extreme data points. The performance of the developed model was evaluated using powerful metrics such as correlation coefficient and root mean squared error.

After several executions and function evaluations, an ANN was found to be the best technique to predict propped fracture conductivity for different mineralogy. The proposed ANN models resulted in less than 7% error between actual and predicted values. In this study, in addition to the development of an optimized ANN model, explicit empirical correlations are also extracted from the weights and biases of the fine-tuned model. The proposed model of propped fracture conductivity was then compared with the commonly available correlations. The results revealed that the proposed mineralogy based propped fracture conductivity models made the predictions with a high correlation coefficient of 94%.

This work clearly shows the potential of computer-based ML techniques in the determination of mineralogy based propped fracture conductivity. The proposed empirical correlation can be implemented without requiring any ML-based software.
Single Well Microseismic Monitoring Leveraging Hybrid Cable Combining Both DAS and Traditional Geophones
Authors: Mizuno Takashi , Le Calvez Joel , Cuny Theo , Chen Yu
Published: December 2021

The single monitoring well configuration is a favorable option for microseismic monitoring considering risk and cost. It has commonly been used in various industries for decades. When using a single monitoring well, we rely among other things on the waveforms’ polarization information to accurately locate detected microseismic events. Additionally, using a large array aperture reduces hypocenter's uncertainty.

Instead of solely relying on 3C geophones to achieve such objectives, we propose to combine 3C sensors and distributed acoustic sensing (DAS) equipment. It is quite a cost-effective solution, and it enables us to leverage each system's strength while minimizing their respective limitations when considered individually. We present the technical feasibility of such a hybrid microseismic monitoring system using data acquired during a monitoring campaign performed in the Montney formation, Canada. In this dataset, the optic fiber (DAS) is located in the wireline cable used to deploy the 3C geophones; themselves located at the bottom of the DAS wireline cable. Though different acquisition systems are employed for the geophone array and the DAS array, both datasets are GPS time stamped so that data can be processed properly. We scan the DAS data using an STA/LTA event detection, and we integrate with the 3C geophone data. We find the microseismic waveform in both the DAS and the geophone sections and confirm the arrival times are consistent between DAS and geophones. Once datasets are merged, we determine hypocenters using a migration-based event location method for such hybrid array. The uncertainty associated with the event located using the hybrid DAS – geophone array is smaller than for any of the systems looked at independently thanks to the increased array aperture. This case study demonstrates the viability and efficiency of the next generation of a single well acquisition system for microseismic monitoring. Not only does it lower event location uncertainty, but it is also more reliable and cost-effective than the conventional approaches.