bluuebunny/crossref_metadata_2025_split huggingface dataset:
Control of Pore Types and Fracture Intensity on the P-Wave Velocity of Carbonate Rocks
Authors: Abdlmutalib Ammar , Abdullatif Osman 
Published: April 2019

Abstract
The study objective is to determine the major factors controlling on acoustic and geomechanical properties of carbonate rocks of Jurassic D5 Member of Dhruma Formation. The study integrates petrophysical, petrographic, and geomechanical analysis to characterize different lithofacies, diagenetic properties, shear and compressional wave velocity, rock strength, dynamic elastic moduli, porosity and permeability of carbonate rocks. A total of sixty samples were collected, petrographic thin sections and Scanning Electron Microscopic images were prepared, small cubes and core plugs were prepared for porosity and permeability measurements as well as wave velocities and point load index tests. Porosity and permeability exhibited moderate to poor correlations. P-wave and S-wave velocities are moderately correlated with porosity. However, they showed better correlation with permeability. Poor to moderate direct correlation between dynamic elastic moduli (Poisson ratio and Young modulus) and porosity were found. The lithofacies with large fracture intensity are related to small P-wave velocity values. Four classes were found based on pore type and diagenetic classifications control on acoustic properties: Class 1 is characterized by moldic and intraparticle pore types with limited microporosity, Class 2 is characterized by intensive micro-fracturing, class 3 is intensively cemented, and Class 4 is characterized by microporosity. Micro-fractures pore type samples show the best wave velocity versus porosity correlation followed by densely cemented microporosity and finally moldic and intraparticle show the weakest correlation. Vertical semi-variograms were measured for P and S-wave velocity as well as porosity. A spherical model was found for P and S-wave velocities with zero nugget values and sill values equal to 3 meters. Hole effect reflecting the control of cyclicity was found. Porosity semi-variogram shows exponential modeling with zero nugget value and sill value equal to three meters. This difference in semivariogram between velocity and porosity supports weak and moderate correlations between them.
A Real-Time Pipeline Tracking Using a Forward-Looking Sonar
Authors: Tipsuwan Yodyium , Kasetkasem Teerasit , Hoonsuwan Phakhachon , Leangaramkul Apinya 
Published: April 2019

Abstract
The pipeline inspection is one of the most critical tasks in the oil and gas industries. The operation of a remotely operated vehicle (ROV) for the pipeline inspection is very costly since it requires both a human operator and the support vessel to which an ROV must be tethered. Furthermore, this tether also limits the surveillance ability of an ROV. Thus, the use of autonomous underwater vehicles (AUVs) can greatly reduce the operation cost of pipeline inspection since an AUV can freely and automatically navigate without tethering to support vessel. In order for an AUV to navigate automatically under the limited vision in the underwater environment, the forward-looking sonar (FLS) is the essential part since the quality of images captured by an optical camera degrade significantly by the turbid water and the low-light condition whereas images produced from an acoustic sonar
As a result, in this work, we are interested in the use of a 2-D multi-beam Forward-Looking Sonar (FLS) to capture echo images on a frontal vision since acoustic signals can pass through tiny particles in turbid medium water [1]. This deployment ensures that an image of pipelines can be captured regardless of low underwater visibility conditions. Other types of sonars that are regularly used in underwater visual inspection include the side scan sonar (SSS), synthetic aperture sonar (SAS), and multi-beam echo sounder (MBES).
There are a limited number of works that focus on the pipeline detection problem. An optical camera was employed in [2] for visual feedback and heading control, SSS and MBES were used in [3], [4] and [5] for pipeline tracking, and, in [6], FLS was used for linear object detection and tracking.
Integration of Latest Laboratory, Software and Retarded Acid Technologies to Increase Efficiency of Acid Treatments in Carbonates: Case Studies from Central Asia
Authors: Abdrazakov Dmitriy , Ziauddin Murtaza , Vernigora Denis , Beletskaya Anna , Yakimchuk Ivan , Olennikova Olesya , Usoltsev Dmitriy , Nikolaev Max , Panga Mohan , Burlibayev Askhat 
Published: April 2019

Abstract
Acidizing treatments in carbonates often result in significant skin decrease due to high reactivity of the formation with acids. Noticeable production increase or inability to run analysis tools after the treatment may lead to the conclusion that the matrix acidizing job was performed efficiently, when, in fact, the job was not optimized in terms of fluid volumes, acid types, wellbore coverage, and pumping rates. As a result, the final skin is not as low as it could be, and, most importantly, medium - and long-term post-acidizing production decline is faster than it could be with an optimized treatment.
To overcome these concerns, an integrated approach to acidizing treatments was implemented for different oil fields in Kazakhstan. The integrated approach consists of comprehensive laboratory testing, which includes core flow tests with subsequent 3D computer tomography scanning. The tests help to determine wormholing regimes and channel geometry while providing calibration points for acid-rock interaction curves. These coefficients are used in the acidizing modeling software, which enables optimization of fluid volumes, pumping rates, and diversion strategy. The approach suggests the use of a single-phase retarded acid system is the most effective method of keeping the treatment in the dominant wormhole regime, especially at elevated temperature. The integrated approach loop is closed by the analysis of the distributed temperature sensor data to calibrate the efficiency of diversion and reservoir injectivity profile.
The approach was introduced for different oil fields in Kazakhstan, with a variety of conditions: depths up to 5000 m and temperatures up to 145°C. The approach helped to optimize acid volumes by as much as 44% to achieve an optimum skin. In the mid-term perspective, this approach helped to reduce the production decline rate by at least 20%, and ongoing post-treatment analysis is even more promising.
Large Liquid Volume Deep Penetration Acidizing in Iraq Missan Oilfield - 3 Case Study
Authors: Gao Jichao , Feng Puyong , Wang Da , Shao Shangqi , Cui Bo , Wang Gui 
Published: April 2019

Abstract
Matrix acidizing is widely used for removing damage of carbonate reservoirs. In 2017, more than 70 matrix stimulation operations have been conducted in Iraq Missan oilfield. However, for wells with no severe damage and low production performance which are influenced by formation energy decreasing, the effect of conventional matrix is limited. In order to stimulate these wells, a new acidizing technique has been developed which is called large liquid volume deep penetration acidizing.
According to the Darcy Productivity Equation, for carbonate reservoir, decreasing the skin factor below 0 would also increase production even if the skin factor is 0. That is the theoretical basis of large liquid volume deep penetration acidizing. The key points of this method are injection volume and acid system characters. Total injection volume is even twice as large as that of conventional matrix acidification. The acid system should have characteristics such as retarded acid-rock reaction rate and low leakoff coefficient. Viscoelastic surfactant based acid PA-VES and gelled acid PA-GL are used in these works.
In high permeability formation, the viscosity of PA-VES [20 wt% HCL and 8 wt% VES-1] reaches a peak of more than 400 cp at a shear rate of 170 S−1 at 120°C, which would drive acid flowing into tight formation. Other characteristics such as corrosion inhibition, surface tension, inter-surface tension, iron control and sludge prevention have been tested. Gelled acid is widely used because of its economic benefit, its rheology behavior is tested too. During injecting procedure, optimizing the injection rate and choosing large acid volume to produce long effective wormhole in formation, in this way the oil and gas seepage resistance are reduced, deep oil and gas reservoir area is connected, and oil production is improved. 3 wells have been stimulated using this technique in Missan oilfield which achieved the good results.
Large liquid volume deep penetration acidizing still belong to matrix acidizing because of non-fracturing formation. So that this method do not need a rig and would save cost. This paper introduces a novel method to stimulate low formation energy wells and low pollution wells, which is used in Iraq Missan oilfield for the first time.
Application of Group Fracturing Technology in the Old Area of Low Permeable Oilfield: A Case from Jilin Oilfield, Songliao Basin
Authors: Xu Jianguo , Zhao Chenxu , Zheng Jiangang , Xuan Gaoliang , Zhang Ruquan , Peng Chong , Liu Hongxia 
Published: April 2019

Abstract
In recent years, the investment of new area productivity construction in Jilin oil field is high, stabilized production becomes more and more difficulty, so the strategic center of oil field transfers to the refracturing of old well, however, the comprehensive water cut and recovery of old oil field is high, and the remaining oil dispersed, increasing production and increasing efficiency by refracturing becomes more and more difficulty. In order to deal with these challenges and realize the benefits of tapping in old area, the new idea of "group fracturing" was proposed basing on the concept of volumetric fracturing, starting from the reconsideration of reservoir geology, injection production unit for the smallest study unit, and integrating multiple fracturing method, we conduct a series of technical studies and field experiment in the old area of Jilin oilfield. The group fracturing technology series mainly includes the following: (1) The high strength positioning and plugging technique for re-orientation fracturing; (2) Energy develop before fracturing and fast energy storage technique in fracturing; (3) Synchronous fracturing technique of multi wells; (4) Synchronous fracturing technique of oil and water well, re-orientation fracturing technique of water well; (5) Fracturing combining with rapid profile control and water plugging technique; (6) "Factory-oriented construction".Since 2016, the group fracturing has carried out a total of 143 wells in 14 blocks in the old area, which has achieved good results. Compared with the conventional fracturing in the same area, the economic efficiency is increased by 10.2%, the oil increase of the single well is increased by 1 times, and the effective period of the measure is raised by 50%. The practice shows that the group fracturing technique is an effective measure to exploit the benefits of the old area in the low permeability oilfield.
Numerical Simulation Study of Focused Borehole to Surface Electric Imaging
Authors: Hu Haitao , Xiao Zhanshan , Zhao Baocheng , Yu Zhennan , Zhu Ruiming , Liu Jianguo 
Published: April 2019

Abstract
Focused borehole to surface electric imaging is researched through numerical simulation in this study, this method makes downhole electrical logging synchronize with three dimensional space electrical exploration near the well, and combines borehole electrical logging with surface electrical prospecting, which can expand spatial scale of well logging evaluation technology and increase vertical resolution of borehole to surface electric imaging evaluation technology. This method can be used for detecting the geological information around well and between wells and wells. It provides a new means for exploration of residual oil distribution and evaluation of unconventional reservoirs fracturing effect. In this method, a new electrode structure, multi frequency focused high power transmission mode and surface reception modes are adopted. Based on the three dimensional finite element numerical simulation method, the instrument response characteristics in homogeneous formation and in homogeneous formation are analyzed. The influences of electrode depth, electrode length, and current return electrode orientation on surface potential distribution are analyzed. The results indicate that borehole to surface electric imaging system can effectively identify formation resistivity anomalies. The larger the spatial scale of resistivity anomaly, the better the recognition effect. Under certain conditions, downhole emission electrode depth is inversely proportional to surface potential distribution distortion, and downhole emission electrode length is proportional to it. When current return electrode B is placed far enough from the wellhead, the influence of electrode B orientation on surface potential distribution is negligible.
Signal to Noise Ratio Enhancement Using Empirical Wavelet Transform
Authors: Lee Wei Yi , Hamidi Rosita , Ghosh Deva , Musa Mohd Hafiz 
Published: April 2019

Abstract
Noise is the unwanted energy in a seismic trace opposed to the signals corresponding to reflected energy from the subsurface features. Since it can overlap with the main signals’ energy and conceal the geological information, noise attenuation is one of the most important steps in seismic data processing. The most common method is frequency filtering. However, due to its limitations on separating the noise from signals, this method usually results in hurting the signal. Hence, it is important to develop an alternative method that can attenuate the noise without affecting the signal. Filters based on time-frequency analysis of the data can have a better separation of the noise from signal as they maintain the time localization of events while presenting their frequency content simultaneously.
One of the recent approaches to time-frequency analysis of signals is the Empirical Wavelet Transform (EWT) which provides adaptive wavelet filter bank for signal analysis. In this paper, a filter is designed based on EWT for random noise attenuation and is applied on both synthetic and real data. To evaluate the proposed filter performance, its results are compared with the filters based on Short Time Fourier Transform and Wavelet transform. As the EWT filter separate different seismic features using the adaptive basis wavelets, it can attenuate the noise while preserving the signals with higher precision.
Per-instance Differential Privacy
Authors: Wang Yu-Xiang 
Published: April 2019

We consider a refinement of differential privacy --- per instance differential privacy (pDP), which captures the privacy of a specific individual with respect to a fixed data set. We show that this is a strict generalization of the standard DP and inherits all its desirable properties, e.g., composition, invariance to side information and closedness to postprocessing, except that they all hold for every instance separately. We consider a refinement of differential privacy --- per instance differential privacy (pDP), which captures the privacy of a specific individual with respect to a fixed data set. We show that this is a strict generalization of the standard DP and inherits all its desirable properties, e.g., composition, invariance to side information and closedness to postprocessing, except that they all hold for every instance separately. When the data is drawn from a distribution, we show that per-instance DP implies generalization. Moreover, we provide explicit calculations of the per-instance DP for the output perturbation on a class of smooth learning problems. The result reveals an interesting and intuitive fact that an individual has stronger privacy if he/she has small ``leverage score'' with respect to the data set and if he/she can be predicted more accurately using the leave-one-out data set. Simulation shows several orders-of-magnitude more favorable privacy and utility trade-off when we consider the privacy of only the users in the data set. In a case study on differentially private linear regression, provide a novel analysis of the One-Posterior-Sample (OPS) estimator and show that when the data set is well-conditioned it provides $(\epsilon,\delta)$-pDP for any target individuals and matches the exact lower bound up to a $1+\tilde{O}(n^{-1}\epsilon^{-2})$ multiplicative factor. We also demonstrate how we can use a ``pDP to DP conversion'' step to design AdaOPS which uses adaptive regularization to achieve the same results with $(\epsilon,\delta)$-DP.
Nearly Injective Semimodules
Authors: Alsaebari Sarah H. A. , Alhossaini Asaad M. A. 
Published: April 2019

An injectivity in the category of semimodules over semiring was studied by many authors recently. On the other hand, the concept of injectivity, in the category of modules over ring, was generalized in many different directions. In particular, injective modules relative to preradical were some of those generalizations.
As an analogue to module theory, in this paper, we introduce and investigate the notion of "injective semimodule relative to Jacobson radical (namely nearly injective semimodule)".
Capital Adequacy and its Impact on Banking Liquidity Risk Applied Study in the Bank of the Islamic National and Commercial Iraqi for the Period (2012-2017)
Authors: Omran Qassem Ali 
Published: April 2019

The aim of this paper is to highlight one of the risks facing the banking system in general and the Iraqi in particular, both Islamic and commercial, resulting from the low liquidity of banks from their safe levels, which expose the bank to a number of effects, especially when exposed to sudden withdrawals through measuring and analyzing the banking liquidity risk of banking and the statement The most important means used to processing these risks, including the adequacy of capital according to the Basel II Accord. Two banks, the National Islamic Bank and the Commercial Bank of Iraq, were selected and the indicators of liquidity risk were used. Statement of the Effect of the Capital Adequacy Tool as a Tool that Contributes to the Absorption of Banking Risks and their Effects in Mitigating Liquidity Risk The indicators were analyzed and tested by testing F, P-value and impact statement through the R2 parameter using the ANOVA analysis. There is a significant effect of the capital adequacy ratio on the liquidity risk of banks and both banks to varying degrees on the basis of which the alternative hypothesis was accepted. The paper also reached the recommendations of the most important of which is the need to achieve a balance between the size of the balances utilized in the various banking fields and what is maintained, Exceed the capital adequacy ratios for the specified rates by the Central Bank of Iraq.
Reflexión mínima. En torno a la pregunta ¿qué podemos entender por filosofía?
Authors: Freire Hermosilla Antonio 
Published: April 2019

Reflexión mínima. En torno a la pregunta ¿qué podemos entender por filosofía? Brief reflection around the question, what can we understand as philosophy? Reflexão mínima. Em torno da pergunta o que podemos entender por filosofia?
O modelo dos múltiplos fluxos de Kingdon e as políticas de Segurança Pública: o caso do programa “Pacto pela Vida” de Pernambuco (2007-2013)
Authors: Monteiro Lorena , Rodrigues Diego , Dos Santos Júnior José Elísio 
Published: April 2019

Este trabalho teve como objetivo analisar o programa de Segurança Pública “Pacto pela vida” implementado no Estado de Pernambuco entre 2007 e 2013 a partir do modelo dos múltiplos fluxos de Kingdon. Demonstra-se que ocorreu uma confluência de fluxos que possibilitou a formulação e a implementação do programa “Pacto pela Vida”, como a percepção e o diagnóstico do problema da violência que levou a contratação de uma empresa de consultoria para elaboração de um feedback de ações, a existência de um empreendedor político, que trouxe para dentro do governo o “estado da arte” do debate acadêmico sobre a questão da violência e as propostas em termos de segurança pública para a formulação do programa, assim como, a existência de um corpo técnico que dialogou com a sociedade civil e a comunidade as soluções. Todos esses fluxos, alinhados ao fato de que o governador Eduardo Campos adotara a questão da segurança pública como política de governo num cenário nacional propício as discussões sobre segurança pública, com as articulações do Fórum Brasileiro de Segurança Pública, a proposta do Plano Nacional de Segurança Pública, etc, fortaleceram a formulação e a implementação do programa. Através de dados primários e secundários esse trabalho reconstruiu como esses fluxos confluíram numa janela de oportunidades que possibilitou a implementação do programa Pacto pela vida, assim como os resultados, em termos de indicadores sociais alcançados. Argumenta-se, que, assim como outras políticas públicas no Brasil consideradas “exitosas”, a necessidade da confluência dos fluxos prejudica a continuidade das políticas, como foi o caso do Programa “Pacto pela Vida” implementado em Pernambuco.
PENGEMBANGAN MODUL FISIKA BILINGUAL MATERI HUKUM NEWTON PADA SISWA SMA KELAS X UNTUK MENINGKATKAN MOTIVASI BELAJAR FISIKA TAHUN AJARAN 2017/2018
Authors: Jannah Zulfa Baijatul , Islahudin Islahudin , Darmayanti N .W. S. 
Published: April 2019

Penelitian ini untuk mengembangkan Modul Fisika Bilingual pada bahasan hukum newton, untuk meningkatkan motivasi belajar siswa SMA Kelas X. Adapun tujuan dari penelitian ini yaitu (1) untuk mengetahui kevalidan media pembelajaran modul fisika bilingual pada materi hukum newton untuk meningkatkan motivasi belajar siswa kelas X,(2) Untuk mengetahui keefektifan media pembelajaranmodul fisika bilingual pada materi hukum newton untuk meningkatkan motivasi belajar siswa kelas X. (3) Untuk mengetahui kepraktisan media pembelajaran modul fisika bilingual pada materi hukum newton untuk meningkatkan motivasi belajar siswa kelas X. Penelitian ini menggunakan metode research and development (R & D). Sebagai subjek dalam penelitian ini adalah siswa SMAN 8Mataram Kelas XMIA 5 . Model pengembangan yang digunakan adalah Dick & Carey yang terdiri dari 10 langkah yang harus diikuti untuk menghasilkan produk berupa Modul Fisika Bilingual. Data diperoleh melalui angket dan dokumentasi. Teknik analisis data yang digunakan adalah deskriptif kualitatif untuk mengukur motivasi belajar siswa. Hasil penelitian menunjukkan bahwa modul fisikabilingual memiliki kriteria baik berdasarkan penilaian dari ahli dan praktis. Modul fisika bilingual yang di kembangkan juga memiliki kriteria baik untuk meningkatkan motivasi belajar siswa dengan persentase sebesar 80,27% bila di bandingkan sebelum menggunakan modul fisika bilingual yaitu sebesar 51,31%. Peningkatan motivasi belajar siswa secara klasikal juga berada pada kriteria sedang dengan normalisasi gain sebesar 0,59. Berdasarkan hasil dari penelitian ini dapat di simpulkan bahwa modul fisika bilingual dapat meningkatkan motivasi belajar siswa kelas X SMAN 8 Mataram tahun pelajaran 2017/2018.