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Iso-propyl caprylate and iso-propyl linolenate synthetic fluids as novel alternatives in deep-water drilling operations:Critical fluid properties and aerobic biodegradability assessments

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Petroleum 2024年第2期10卷 254-264页

作者： Adewale Johnson Folayan Adewale Dosunmu Aleruchi Boniface Oriji Department of Petroleum and Gas Engineering University of Port Harcourt university of Port Harcourt

Present drilling fluids for deep water wells have severe degenerative effect on the environment with high operational and disposal costs. Thus, making them less desirable in recent times. Ester synthetic drilling fluid provides a novel environmentally friendly alternative but conventional ester-based drilling fluids exhibit high viscosities in deep-water wells causing excessive equivalent circulating density(ECD) and increased risk of lost circulation owing to narrow mud density window. This study experimentally investigates the critical fluid properties and aerobic biodegradability potentials of two newly developed deep-water synthetic ester drilling fluids namely: iso-propyl caprylate(COIPE) and iso-propyl linolenate(LOIPE) synthetic fluids and their comparison with synthetic-paraffin(SP-SBF) and isomerized-olefin(IOSBF) synthetic hydrocarbon fluids. The esters of iso-propyl caprylate and iso-propyl linolenate were produced from the isolation of ester mixtures that were obtained from the homogeneous catalytic transesterification of coconut and linseed plant oil biomass respectively. The COIPE was isolated from the coconut oil iso-propyl ester mixture by low-pressure fractional distillation technique. While fractional distillation and crystallization were used to isolate the LOIPE ester from the linseed oil iso-propyl ester mixture. Meanwhile, the aerobic biodegradation investigation was conducted by a modified oxygen consumption respirometry technique. The GC-MS analysis of the COIPE and LOIPE showed that the former contains essentially of lower saturated carbon compounds(C8). Whereas the latter contains higher molecular weight and unsaturated carbon compounds(C18+). The COIPE and LOIPE kinematic viscosity values are in good agreement with that of the reference synthetic hydrocarbon fluid samples(SP-SBF and IO-SBF).Although, the COIPE synthetic ester has lower viscosity value owing to the presence of shorter chain and saturated carbon atoms(C8 esters). Similarly,

关键词： Aerobic biodegradation Critical fluid properties Deep-water wells Esters' isolation: isomerized-olefin (IO-SBF) Iso-propyl caprylate (COIPE) Iso-propyl linolenate (LOIPE) Respirometry technique Synthetic-paraffin (SP-SBF)

Numerical study on the blocking effect of skin on Flash-Ball Impact and damage assessment

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Defence Technology（防务技术） 2024年第3期33卷 532-545页

作者： Dihua Ouyang Chunwei Qin Xiaowen Qin Qiantao Zhang Xingyu Liu Xi'an university of Architecture and Technology Xi'an 710055China Analysis and Testing Center Xi'an University of Architecture and TechnologyXi'an 710055China Engineering university of PAP Xi'an 710086China

To explore the response law of non-lethal large-size kinetic energy projectiles to blunt attack on skin tissue,and to evaluate the skin injury characteristics of the attacked personnel and the use safety of kinetic energy *** on the LS-DYNA simulation software,a three-layer skin simulation model and a Flash-Ball rubber bullet model are established,and the force-time and deformation-time biomechanical corridors of the Flash-Ball rubber bullet impacting human skin tissue are *** corridor curve and the energy transfer and diffusion are analyzed and *** safety evaluation of the damage caused by the rubber bullet shooting a human body at different distances is carried out using the empirical formula of the penetration ***,the safe shooting distance is *** results show that the model used in the simulation has a good correlation with the experimental data,its biomechanical corridor characteristics are different from those of conventional vehicle impact and smallsize projectile response *** energy transfer and action time of medium and low-speed impact may cause greater *** fat layer is the largest energy absorption *** minimum safe shooting distance to ensure skin tissue from penetrating damage is 15.8 m,and the limit specific kinetic energy of skin damage is 7.88 J/cm^(2).This study can be extended to the study of biomechanical response law and safety evaluation under the impact of the same type of large kinetic energy projectile,which provides an important theoretical reference for the police to use large kinetic energy projectiles to conduct safe shooting in peacekeeping operations.

关键词： KIPs Blunt strike Biomechanical response Damage analysis

High-energy,alignment-insensitive,injection-seeded Q-switched Ho:yttrium aluminum garnet single-frequency laser

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High Power Laser Science and Engineering 2023年第5期11卷 157-163页

作者： Dong Yan Yue Yuan Yunpeng Wang Jiawei Fan Jiaze Wu Xiaoming Duan Sining Li Tongyu Dai Youlun Ju National Key Laboratory of Tunable Laser Technology Harbin Institute of TechnologyHarbinChina Department of Physics and Chemistry PLA Army Academy of Special OperationsGuangzhouChina Institute of Laser Engineering Faculty of Materials and ManufacturingBeijing University of TechnologyBeijingChina

A high-energy,alignment-insensitive,injection-seeded Q-switched Ho:yttrium aluminum garnet(YAG)singlefrequency laser is *** the slave Q-switched laser and the seed laser are Ho:YAG ring lasers based on a pair of corner cubic *** seed laser has an available power of 830 mW at 2096.667 *** 100 Hz,the Q-switched Ho:YAG laser provides a single-frequency pulsed output using injection-seeded *** 7.3 mJ single-frequency pulse energy from the slave laser has a pulse width of 161.2 ns and is scaled to 33.3 mJ after passing through the Ho:YAG single-pass *** to the measurement results of the heterodyne beating technique,the single-frequency pulse has a half-width of 4.12 MHz.

关键词： alignment insensitivity corner cubic reflector high energy injection seeding single frequency

Reliability analysis of extended generalized inverted exponential distribution with applications

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Journal of Systems Engineering and Electronics 2016年第2期27卷 484-492页

作者： Arwa M.Alshangiti M.Kayid M.Almulhim Department of Statistics and operations Research College of Science King Saud University

A general version of the inverted exponential distribution is introduced, studied and analyzed. This generalization depends on the method of Marshall-Olkin to extend a family of distributions. Some statistical and reliability properties of this family are studied. In addition, numerical estimation of the maximum likelihood estimate（MLE） parameters are discussed in details. As an application, some real data sets are analyzed and it is observed that the presented family provides a better fit than some other known distributions.

关键词： inverted exponential distribution reliability properties statistical properties maximum likelihood estimates applications

Differences in the system accuracy acceptability of four types of blood glucose monitoring systems against five different standards

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iLABMED 2024年第2期2卷 70-78页

作者： Tengjiao Wang Lina Zhang Lijun Gong Yangmei Xin Liang Han Na Li Peng Peng Xiuying Zhao Runqing Li Laboratory Medicine Department Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijingChina operations Management Department Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijingChina Nursing Department Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijingChina Equipment Management Department Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijingChina Clinical Administration Department Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijingChina

Objective:This study aimed to evaluate the system accuracy of four types of blood glucose monitoring systems(BGMSs)and explore the differences in the system accuracy acceptability of each BGMS against five different ***:The glucose measurement values obtained from four types of BGMSs(Roche Accu-Chek® Performa,Bayer Contour™ TS,Sinomedisite Glupad® H1 Plus,and Sinocare® Gold-Accu)were evaluated against the reference values obtained from the biochemical analyzer of the central *** system accuracy acceptability of each BGMS was determined using the criteria specified in five standards,namely the International Organization for Standardization(ISO)15197:2003,Clinical Laboratory Standards Institute(CLSI)POCT12-A3,ISO 15197:2013,Chinese Society of Laboratory Medicine(CSLM)consensus,and US Food and Drug Administration(FDA)***:From 2018 to 2022,10,980 pairs of measurement values were obtained from 366 glucose meters of four types of *** correlations were observed between the glucose measurement values from the BGMSs and the reference values from the biochemical analyzer of the central *** correlation coefficient r was 0.995 for Roche Accu-Chek® Performa,0.994 for Bayer Contour™ TS,0.983 for Sinomedisite Glupad® H1 Plus,and 0.997 for SinocareR *** acceptability criteria specified in ISO 15197:2003 were met by 100.00%(135/135)of the glucose meters of Roche Accu-Chek® Performa,100.00%(109/109)of Bayer Contour™ TS,81.61%(71/87)of Sinomedisite Glupad® H1 Plus,and 100.00%(35/35)of SinocareR ***,the acceptability criteria specified in ISO 15197:2013 were met by 99.26%(134/135)of the glucose meters of Roche Accu-Chek® Performa,88.07%(96/109)of Bayer Contour™ TS,58.62%(51/87)of Sinomedisite Glupad R H1 Plus,and 91.43%(32/35)of SinocareR ***:Among the four types of BGMSs evaluated,the glucose meters of Roche Accu-Chek® Performa exhibited superior system *** system accura

关键词： blood glucose blood glucose monitoring system comparative study data accuracy

Formal Verification of Data Modifications in Cloud Block Storage Based on Separation Logic

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Chinese Journal of Electronics 2024年第1期33卷 112-127页

作者： Bowen ZHANG Zhao JIN Hanpin WANG Yongzhi CAO Key Laboratory of High Confidence Software Technologies (MOE) School of Computer Science Peking University School of Computer and Artificial Intelligence Zhengzhou University School of Computer Science and Cyber Engineering Guangzhou University

Cloud storage is now widely used, but its reliability has always been a major concern. Cloud block storage(CBS) is a famous type of cloud storage. It has the closest architecture to the underlying storage and can provide interfaces for other types. Data modifications in CBS have potential risks such as null reference or data *** verification of these operations can improve the reliability of CBS to some extent. Although separation logic is a mainstream approach to verifying program correctness, the complex architecture of CBS creates some challenges for verifications. This paper develops a proof system based on separation logic for verifying the CBS data modifications. The proof system can represent the CBS architecture, describe the properties of the CBS system state, and specify the behavior of CBS data modifications. Using the interactive verification approach from Coq, the proof system is implemented as a verification tool. With this tool, the paper builds machine-checked proofs for the functional correctness of CBS data modifications. This work can thus analyze the reliability of cloud storage from a formal perspective.

关键词： Cloud computing Behavioral sciences Reliability Formal verification

Lithological Facies Classification Using Attention-Based Gated Recurrent Unit

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Tsinghua Science and Technology 2024年第4期29卷 1206-1218页

作者： Yuwen Liu Yulan Zhang Xingyuan Mao Xucheng Zhou Jingwen Chang Wenwei Wang Pan Wang Lianyong Qi College of Computer Science and Technology China University of Petroleum(East China)Qingdao 266580China Shandong Provincial university Laboratory for Protected Horticulture Weifang University of Science and TechnologyShouguang 262700China School of Mechanical Electrical and Information EngineeringShandong UniversityWeihai 264209China Shandong Provincial Key Laboratory of Network Based Intelligent Computing University of JinanJinan 250022China School of Modern Posts Nanjing University of Posts and TelecommunicationsNanjing 210023China

Lithological facies classification is a pivotal task in petroleum geology, underpinning reservoir characterization and influencing decision-making in exploration and production operations. Traditional classification methods, such as support vector machines and Gaussian process classifiers, often struggle with the complexity and nonlinearity of geological data, leading to suboptimal performance. Moreover, numerous prevalent approaches fail to adequately consider the inherent dependencies in the sequence of measurements from adjacent depths in a well. A novel approach leveraging an attention-based gated recurrent unit (AGRU) model is introduced in this paper to address these challenges. The AGRU model excels by exploiting the sequential nature of well-log data and capturing long-range dependencies through an attention mechanism. This model enables a flexible and context-dependent weighting of different parts of the sequence, enhancing the discernment of key features for classification. The proposed method was validated on two publicly available datasets. Results demonstrate a considerably improvement over traditional methods. Specifically, the AGRU model achieved superior performance metrics considering precision, recall, and F1-score.

关键词： attention mechanism facies classification GRU MLP(multilayer perceptron)

Programmable silicon-photonic quantum simulator based on a linear combination of unitaries

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Photonics Research 2024年第8期12卷 1760-1767页

作者： YUE YU YULIN CHI CHONGHAO ZHAI JIESHAN HUANG QIHUANG GONG JIANWEI WANG State Key Laboratory for Mesoscopic Physics School of Physics Peking University Frontiers Science Center for Nano-optoelectronics & Collaborative Innovation Center of Quantum Matter Peking University Collaborative Innovation Center of Extreme Optics Shanxi University Yangtze Delta Institute of Optoelectronics Peking University Hefei National Laboratory

Simulating the dynamic evolution of physical and molecular systems in a quantum computer is of fundamental interest in many applications. The implementation of dynamics simulation requires efficient quantum algorithms. The Lie-Trotter-Suzuki approximation algorithm, also known as the Trotterization, is basic in Hamiltonian dynamics simulation. A multi-product algorithm that is a linear combination of multiple Trotterizations has been proposed to improve the approximation accuracy. However, implementing such multiproduct Trotterization in quantum computers remains challenging due to the requirements of highly controllable and precise quantum entangling operations with high success probability. Here, we report a programmable integrated-photonic quantum simulator based on a linear combination of unitaries, which can be tailored for implementing the linearly combined multiple Trotterizations, and on the simulator we benchmark quantum simulation of Hamiltonian dynamics. We modify the multi-product algorithm by integrating it with oblivious amplitude amplification to simultaneously reach high simulation precision and high success probability. The quantum simulator is devised and fabricated on a large-scale silicon-photonic quantum chip, which allows the initialization, manipulation, and measurement of arbitrary four-qubit states and linearly combined unitary gates. As an example, the quantum simulator is reprogrammed to emulate the dynamics of an electron spin and nuclear spin coupled system. This work promises the practical dynamics simulations of real-world physical and molecular systems in future large-scale quantum computers. ? 2024 Chinese Laser Press

关键词： Numerical simulation Quantum computation Quantum simulator Quantum technology Signal processing Silicon photonics

FOLMS-AMDCNet:an automatic recognition scheme for multiple-antenna OFDM systems

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系统工程与电子技术：英文版 2023年第2期34卷 307-323页

作者： ZHANG Yuyuan YAN Wenjun ZHANG Limin LING Qing Academy of Aeronautical operations Service Naval Aviation UniversityYantai 264001China

The existing recognition algorithms of space-time block code(STBC)for multi-antenna(MA)orthogonal frequencydivision multiplexing(OFDM)systems use feature extraction and hypothesis testing to identify the signal types in a complex communication ***,owing to the restrictions on the prior information and channel conditions,these existing algorithms cannot perform well under strong interference and noncooperative communication *** overcome these defects,this study introduces deep learning into the STBCOFDM signal recognition field and proposes a recognition method based on the fourth-order lag moment spectrum(FOLMS)and attention-guided multi-scale dilated convolution network(AMDCNet).The fourth-order lag moment vectors of the received signals are calculated,and vectors are stitched to form two-dimensional FOLMS,which is used as the input of the deep learning-based ***,the multi-scale dilated convolution is used to extract the details of images at different scales,and a convolutional block attention module(CBAM)is introduced to construct the attention-guided multi-scale dilated convolution module(AMDCM)to make the network be more focused on the target area and obtian the multi-scale guided ***,the concatenate fusion,residual block and fully-connected layers are applied to acquire the STBC-OFDM signal *** experiments show that the average recognition probability of the proposed method at−12 dB is higher than 98%.Compared with the existing algorithms,the recognition performance of the proposed method is significantly improved and has good adaptability to environments with strong *** addition,the proposed deep learning-based model can directly identify the pre-processed FOLMS samples without a priori information on channel and noise,which is more suitable for non-cooperative communication systems than the existing algorithms.

关键词： blind signal identification(BSI) space-time block code(STBC) orthogonal frequency-division multiplexing(OFDM) deep learning fourth-order lag moment spectrum(FOLMS)