检索结果-南通市图书馆

Application of fuzzy comprehensive evaluation method to assess effect of conformance control treatments on water-injection wells

引用

Petroleum 2024年第1期10卷 165-174页

作者： hu Jia Pengwu Li Wei Lv Jianke Ren Chen Cheng rui Zhang Zhengjun Zhou Yanbin Liang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Oil and Gas Technology Research Institute PetroChina Changqing Oilfield Company Oil Production Technology Institute of PetroChina Dagang Oilfield Company

As an effective method to prolong the life of mature field, conformance control in water-injection well has been used wildly. Naturally, effect evaluation of conformance control has attracted great attention because it is an important guideline for the design of later enhanced oil recovery(EOR) plan. Usually,production responses such as excessive water reduction and oil production increment are widely used as the indicators. However, production responses may be unreliable due to the difficulty in determining an effective injection well which is caused by a large number of treated water-injection wells in a well group. Therefore, with the application of fuzzy comprehension evaluation(FCE), five evaluation indexes(injection pressure, injectivity index, slope of hall curve, variation coefficient and homogenization coefficient of injection profile) describe injection responses were selected to establish a new evaluation method in this paper. Based on fuzzy mathematics, FCE reflects the difference of evaluation ***, weights of evaluation indexes were obtained by analytic hierarchy process(AHP), which made the results more convincing. Taking Bai 239 oilfield as an example, the five injection responses indexes were used to assess treatment effect on five water-injection wells by single index evaluation and FCE. The results showed that among the five evaluation indexes mentioned above, the slope of hall curve was the most important factor affected evaluation result. In single index evaluation, opposite results may be produced easily on account of the one-sidedness of single index or human error. Furthermore, we found that effective treatment was a relative concept actually. The result of FCE was consistent with single index evaluation but FCE was more acceptable. This study suggests that FCE could be applied to another field such as water flooding, acidizing and hydraulic fracturing

关键词： Enhanced oil recovery Injection responses Fuzzy mathematics Analytic hierarchy process Effect evaluation

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Space/Air Covert Communications:Potentials,Scenarios,and Key Technologies

引用

China Communications 2024年第3期21卷 1-18页

作者： Mao Haobin Liu Yanming Zhu Lipeng Mao Tianqi Xiao Zhenyu Zhang rui han Zhu Xia Xianggen School of Electronic and Information Engineering Beihang UniversityBeijing 100191China Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore School of Science and Engineering Shenzhen Research Institute of Big Datathe Chinese University of Hong KongShenzhenGuangdong 518172China Department of Electrical and Computer Engineering University of HoustonHoustonTX 77004USA Department of Computer Science and Engineering Kyung Hee UniversitySeoulSouth Korea446-701 Department of Electrical and Computer Engineering University of DelawareNewarkDE 19716USA

Space/air communications have been envisioned as an essential part of the next-generation mobile communication networks for providing highquality global connectivity. However, the inherent broadcasting nature of wireless propagation environment and the broad coverage pose severe threats to the protection of private data. Emerging covert communications provides a promising solution to achieve robust communication security. Aiming at facilitating the practical implementation of covert communications in space/air networks, we present a tutorial overview of its potentials, scenarios, and key technologies. Specifically, first, the commonly used covertness constraint model, covert performance metrics, and potential application scenarios are briefly introduced. Then, several efficient methods that introduce uncertainty into the covert system are thoroughly summarized, followed by several critical enabling technologies, including joint resource allocation and deployment/trajectory design, multi-antenna and beamforming techniques, reconfigurable intelligent surface(RIS), and artificial intelligence algorithms. Finally, we highlight some open issues for future investigation.

关键词： artificial intelligence(AI) sixth generation(6G) space-air-ground integrated networks(SAGINs) space/air covert communications

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Thermal stability improvement and microstructure optimization of high cobalt content Nd-Fe-B magnets via terbium grain boundary diffusion

引用

Journal of Rare Earths 2024年第8期42卷 1531-1538,I0004页

作者： Jiyuan Xu ruiyang Meng Jing Liu Jiateng Zhang rui han Yikun Fang Shengzhi Dong Wei Li Division of Functional Materials Research Central Iron and Steel Research InstituteBeijing100081China

The substitution of Fe by Co in the 2:14:1 phase is an effective method to increase the Curie temperature and enhance the thermal stability of the Nd-Fe-B ***,the accumulation of Co ele ment at the grain boundaries(GBs) changes the GBs from nonmagnetic to ferromagnetic and causes the thinlayer GBs to become rare,In this paper,the method of diffusing Tb element was chosen to improve the microstructure and temperature stability of high-Co *** original sintered Nd_(28.5)Dy_(3)-CO_(x)e_(bal)M_(0.6)B_(i)(x=0,6 wt%,12 wt%;M = Cu,Al,Zr) magnets with different Co contents were diffused with Tb by grain boundary diffusion(GBD).After GBD,high-Co magnets exhibit more continuously distributed thin-layer GBs,and their thermal stability is significantly *** high-Co magnets(x=6 wt%),the absolute value of the temperature coefficient of coercivity decreases from 0.603%/K to0.508%/K in the temperature range of 293-413 K,that of remanence decreases from 0.099%/K to 0.091%/K,and the coercivity increases from 18.44 to 25.04 *** electron microscopy(TEM)characterization reveals that there are both the 1:2 phase and the amorphous phase in the high-Co magnet before and after GBD,EDS elemental analysis shows that Tb element is more likely to preferentially replace the rare earth elements in the 2:14:1 main phase than in the 1:2 phase and the amorphous *** concentration of Tb at the edge of the main phase is much higher than that in the 1:2phase and amorphous phase,which is beneficial to the improvement of the *** preferential replacement of Tb elements at the edge of the 2:14:1 phase and thin-layer GBs with a more continuous distribution are synergistically responsible for improving the thermal stability of high-Co *** study indicates that GBD is an effective method to improve the microstructure and thermal stability of high-Co magnets.

关键词： Nd-Fe-B magnets Coercivity Grain boundary diffusion Thermal stability Micro structure Rare earths

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Facile preparation of a SiC@SiO_(2)nanowire-toughened ZrB_(2)-SiC/SiC bilayer coating with good interfacial bonding,high toughness,and excellent cyclic ablation resistance on C/CA composites

引用

Journal of Advanced Ceramics 2024年第4期13卷 486-495页

作者： Meng Yan Chenglong hu Jian Li Shengyang Pang Bohui Sun Rida Zhao Bin Liang rui Luo Sufang Tang Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

Preparing antioxidant coatings to address the inherent oxidation sensitivity of carbon fiber-reinforced carbon aerogel(C/CA)composites is a feasible way to promote their application in oxidizing environments as thermal insulation ***,preparing the coatings with excellent oxidation and ablation resistance while avoiding evident damage to the C/CA substrate still remains a ***,a SiC@SiO_(2)nanowire-toughened ZrB2–SiC/SiC bilayer coating with a large thickness of 500μm was prepared on C/CA using a one-step low-temperature reaction sintering method,which simultaneously formed a sintered outer layer with even-distributed nanowires and a siliconized gradient inner *** courtesy of the synergic thermal response of the layers and the crack deflection induced by the nanowires,the resulting coating has moderate residual compressive stress of 0.08–1.22 GPa in the interface,high interfacial bonding strength of 6.02 MPa,and good fracture toughness of 4.36 MPa·m^(1/2).Benefited from the optimum components and improved structure,the coating shows excellent cyclic ablation resistance with linear ablation rates of 0.1μm/s at 1650℃for 1500 s(300 s×5 cycles)and 0.4μm/s at 1850℃for 900 s(300 s×3 cycles).The one-step preparation strategy contributes to little damage to the substrate,thus showing the well-preserved mechanical and thermal insulation properties.

关键词： coating carbon fiber reinforced carbon aerogel(C/CA)composites toughness interface residual stress

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Macroscopic model and statistical model to characterize electromagnetic information of a digital coding metasurface

引用

National Science Review 2024年第03期11卷 159-171页

作者： rui Wen Shao Jun Wei Wu Zheng Xing Wang hui Xu han Qing Yang Qiang Cheng Tie Jun Cui Institute of Electromagnetic Space Southeast University State Key Laboratory of Millimeter Waves Southeast University Peng Cheng Laboratory Pazhou Laboratory(huangpu)

A digital coding metasurface is a platform connecting the digital space and electromagnetic wave space, and has therefore gained much attention due to its intriguing value in reshaping wireless channels and realizing new communication architectures. Correspondingly, there is an urgent need for electromagnetic information theory that reveals the upper limit of communication capacity and supports the accurate design of metasurface-based communication systems. To this end, we propose a macroscopic model and a statistical model of the digital coding metasurface. The macroscopic model uniformly accommodates both digital and electromagnetic aspects of the meta-atoms and predicts all possible scattered fields of the digital coding metasurface based on a small number of simulations or measurements. Full-wave simulations and experimental results show that the macroscopic model is feasible and accurate. A statistical model is further proposed to correlate the mutual coupling between meta-atoms with covariance and to calculate the entropy of the equivalent currents of digital coding metasurface. These two models can help reconfigurable intelligent surfaces achieve more accurate beamforming and channel estimation, and thus improve signal power and coverage. Moreover, the models will encourage the creation of a precoding codebook in metasurface-based direct digital modulation systems, with the aim of approaching the upper limit of channel capacity. With these two models, the concepts of current space and current entropy, as well as the analysis of information loss from the coding space to wave space, is established for the first time, helping to bridge the gap between the digital world and the physical world, and advancing developments of electromagnetic information theory and new-architecture wireless systems.

关键词： electromagnetic information theory current entropy current space digital coding metasurface macroscopic model statistical model

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Intellicise Model Transmission for Semantic Communication in Intelligence-Native 6G Networks

引用

China Communications 2024年第7期21卷 95-112页

作者： Wang Yining han Shujun Xu Xiaodong Meng rui Liang Haotai Dong Chen Zhang Ping State Key Laboratory of Network and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China Department of Broadband Communication Peng Cheng LaboratoryShenzhen 518066China

To facilitate emerging applications and demands of edge intelligence(EI)-empowered 6G networks,model-driven semantic communications have been proposed to reduce transmission volume by deploying artificial intelligence(AI)models that provide abilities of semantic extraction and ***,it is not feasible to preload all AI models on resource-constrained ***,in-time model transmission becomes a crucial *** paper proposes an intellicise model transmission architecture to guarantee the reliable transmission of models for semantic *** mathematical relationship between model size and performance is formulated by employing a recognition error function supported with experimental *** consider the characteristics of wireless channels and derive the closed-form expression of model transmission outage probability(MTOP)over the Rayleigh ***,we define the effective model accuracy(EMA)to evaluate the model transmission performance of both communication and *** we propose a joint model selection and resource allocation(JMSRA)algorithm to maximize the average EMA of all *** results demonstrate that the average EMA of the JMSRA algorithm outperforms baseline algorithms by about 22%.

关键词： edge intelligence(EI) model transmission outage probability and accuracy resource allocation semantic communication

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Addressing the alarming link between nonalcoholic fatty liver disease and cardiovascular mortality in men

引用

World Journal of Cardiology 2024年第9期16卷 502-507页

作者： Wen-rui Hao Chun-han Cheng Tzu-hurng Cheng Division of Cardiology Department of Internal MedicineShuang Ho HospitalMinistry of Health and WelfareTaipei Medical UniversityNew Taipei 23561TaiwanChina Division of Cardiology Department of Internal MedicineSchool of MedicineCollege of MedicineTaipei Medical UniversityTaipei 11002TaiwanChina Department of Medical Education Linkou Chang Gung Memorial HospitalTaoyuan 33305TaiwanChina Department of Biochemistry School of MedicineCollege of MedicineChina Medical UniversityTaichung 404328TaiwanChina

This editorial discusses the key findings presented in Batta and Hatwal’s recent paper titled“Excess cardiovascular mortality in men with non-alcoholic fatty liver disease:A cause for concern!”,which was published in the World Journal of *** original article highlights a notable correlation between nonalcoholic fatty liver disease(NAFLD)and increased cardiovascular mortality risk in *** present commentary explores the implications of their findings,discussing potential mechanisms,risk factors,and the urgent need for integrated clinical approaches to mitigate the dual burden of these *** should be placed on the importance of early detection,lifestyle modifications,and interdisciplinary collaboration for improving patient *** editorial aims to highlight the broad implications of NAFLD for cardiovascular health and to advocate for increased awareness and proactive management strategies within the medical community.

关键词： Non-alcoholic fatty liver disease Cardiovascular mortality Men's health Integrated clinical approaches Risk factors

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Exploring the effect of cooling rate on non-isothermal crystallization of copolymer polypropylene by fast scanning calorimetry

引用

China Foundry 2024年第4期21卷 379-386页

作者： Yang Liao Ye-yuan hu Kosuke Ikeda Ryoji Okabe rui-fen Wu Ryota Ozaki Qing-yan Xu Key Laboratory for Advanced Materials Processing Technology School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Composite Laboratory Research&Innovation Center Mitsubishi Heavy Industries Ltd.Nagasaki 8510392Japan

Polypropylene is commonly used as a binder for ceramic injection molding,and rapid cooling is often encountered during ***,the crystallization behavior of polypropylene shows a strong dependence on cooling rate due to its semi-crystalline ***,the influence of cooling rate on the quality of final product cannot be *** this study,the fast differential scanning calorimetry(FSC)test was performed to study the influence of cooling rate on the non-isothermal crystallization behavior and non-isothermal crystallization kinetics of a copolymer polypropylene(PP BC03B).The results show that the crystallization temperatures and crystallinity decrease as the cooling rate *** addition,two exothermic peaks occur when cooling rate ranges from 30 to 300 K·s^(-1),indicating the formation of another crystal ***,Ozawa and Mo equations were used to explore the non-isothermal crystallization kinetics,and it can be concluded that the Mo method is suitable for this study.

关键词： cooling rate crystallization temperature crystallinity non-isothermal crystallization kinetics FSC copolymer polypropylene

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Mitochondrial diseases and mtDNA editing

引用

Genes & Diseases 2024年第3期11卷 303-310页

作者： Min Song Lingqun Ye Yongjin Yan Xuechun Li Xinglong han Shijun hu Miao Yu Department of Cardiovascular Surgery of the First Affiliated Hospital&Institute for Cardiovascular Science Collaborative Innovation Center of HematologyState Key Laboratory of Radiation Medicine and ProtectionSuzhou Medical CollegeSoochow UniversitySuzhouJiangsu 215000China Hai'an People's Hospital NantongJiangsu 226600China

Mitochondrial diseases are a heterogeneous group of inherited disorders character-ized by mitochondrial dysfunction,and these diseases are often severe or even ***-chondrial diseases are often caused by mitochondrial DNA ***,there is no curative treatment for patients with pathogenic mitochondrial DNA *** the rapid development of traditional gene editing technologies,such as zinc finger nucleases and tran-scription activator-like effector nucleases methods,there has been a search for a mitochon-drial gene editing technology that can edit mutated mitochondrial DNA;however,there are still some problems hindering the application of these *** discovery of the DddA-derived cytosine base editor has provided hope for mitochondrial gene *** this paper,we will review the progress in the research on several mitochondrial gene editing technologies with the hope that this review will be useful for further research on mitochondrial gene editing technologies to optimize the treatment of mitochondrial diseases in the future.

关键词： Gene editing Mitochondrialdisease MitochondrialDNA mutation Transcription activator-like effectornucleases Zinc finger nucleases

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Exploring the dynamic three-dimensional chromatin architecture and transcriptional landscape in goose liver tissues underlying metabolic adaptations induced by a high-fat diet

引用

Journal of Animal Science and Biotechnology 2024年第4期15卷 1494-1511页

作者： Guangliang Gao rui Liu Silu hu Mengnan He Jiaman Zhang Dengfeng Gao Jing Li Jiwei hu Jiwen Wang Qigui Wang Mingzhou Li Long Jin Livestock and Poultry Multi‑Omics Key Laboratory of Ministry of Agriculture and Rural Affairs College of Animal Science and TechnologySichuan Agricultural UniversityChengdu 611130China Chongqing Engineering Research Center of Goose Genetic Improvement Institute of Poultry ScienceChongqing Academy of Animal SciencesRongchang DistrictChongqing 402460China

Background Goose, descendants of migratory ancestors, have undergone extensive selective breeding, resulting in their remarkable ability to accumulate fat in the liver and exhibit a high tolerance for significant energy intake. As a result, goose offers an excellent model for studying obesity, metabolic disorders, and liver diseases in mammals. Although the impact of the three-dimensional arrangement of chromatin within the cell nucleus on gene expression and transcriptional regulation is widely acknowledged, the precise functions of chromatin architecture reorganization during fat deposition in goose liver tissues still need to be fully *** In this study, geese exhibited more pronounced changes in the liver index and triglyceride(TG) content following the consumption of the high-fat diet(HFD) than mice without significant signs of inflammation. Additionally, we performed comprehensive analyses on 10 goose liver tissues(5 HFD, 5 normal), including generating highresolution maps of chromatin architecture, conducting whole-genome gene expression profiling, and identifying H3K27ac peaks in the livers of geese and mice subjected to the HFD. Our results unveiled a multiscale restructuring of chromatin architecture, encompassing Compartment A/B, topologically associated domains, and interactions between promoters and enhancers. The dynamism of the three-dimensional genome architecture, prompted by the HFD, assumed a pivotal role in the transcriptional regulation of crucial genes. Furthermore, we identified genes that regulate chromatin conformation changes, contributing to the metabolic adaptation process of lipid deposition and hepatic fat changes in geese in response to excessive energy intake. Moreover, we conducted a cross-species analysis comparing geese and mice exposed to the HFD, revealing unique characteristics specific to the goose liver compared to a mouse. These chromatin conformation changes help elucidate the observed characteristics of fat

关键词： Compartment A/B Goose fatty liver Promoter-enhancer interactions Regulation of gene expression

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：