检索结果-南通市图书馆

Current observation and analysis based on mooring systems in the Andaman Sea

Journal of Oceanology and Limnology 2024年第2期42卷 484-491页

作者： Yimeng WANG Jingsong GUO Dapeng QU Zhixin ZHANG Chalermrat SANGMANEE Varintha VASINAMEKHIN Binghuo GUO First Institute of Oceanography and Key Laboratory of Marine Science and Numerical ModelingMinistry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Shandong Key Laboratory of marine Science and Numerical Modeling Qingdao 266061China Phuket marine Biological Center Department of Marine and Coastal ResourcesPhuket 83000Thailand marine and Coastal Resources Research&Development Institute Department of Marine and Coastal ResourcesBangkok 10210Thailand

The basic structure and intraseasonal evolution of currents in the southeastern Andaman Sea was analyzed based on data collected in 2017 from two subsurface moorings(C1 and C5).Periodic variation in the upper ocean currents of the Andaman Sea was investigated by combining observational and satellite data.Mooring observations show that rapid changes of current speed and direction occurred in May and June,with a significant increase in current velocity at the C1 mooring.In the second half of the year,southward flow dominated at the C1 mooring,and alternating northward and southward flows were evident at the C5 mooring during the same period but the northward flow prevailed in boreal winter.In addition,analysis of the power spectra of the upper currents revealed that the tidal period at both moorings is primarily semidiurnal with weaker energy than that of the low-frequency currents.The upper ocean currents at the C1 and C5 moorings exhibited intraseasonal variation of 30-60 d and 120 d,while the zonal current at the C1 mooring exhibited a notable period of approximately 180 d.Further analysis indicated that the variability of currents in the Andaman Sea is influenced primarily by equatorial Kelvin waves and Rossby wave packets.Moreover,our results suggest that equatorial Kelvin waves from the eastern Indian Ocean entered the Andaman Sea in the form of Wyrtki Jets and propagated primarily along two distinct pathways during the observation period.In addition to coastal boundary Kelvin waves,it was found that a branch of the Wyrtki Jet that directly enters the Andaman Sea and flows northward along the slope of the continental shelf,and reflected Rossby wave packets by topography.

关键词： mooring observation Wyrtki Jet Rossby waves intraseasonal variation

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

An Improved Modulation Strategy for Single-phase Three-level Neutral-point-clamped Converter in Critical Conduction Mode

引用

Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 981-990页

作者： Ning Li Yujie Cao Xiaokang Liu Yan Zhang Ruotong Wang Lin Jiang Xiao-Ping Zhang School of Electrical Engineering Xi'an University of Technology the department of electronics Information and Bioengineering Xi'an Jiaotong University the department of Electrical Engineering and electronics University of Liverpool the department of Electronic Electrical and Systems Engineering University of Birmingham

Two-level totem-pole power factor correction(PFC) converters in critical conduction mode(CRM) suffer from the wide regulation range of switching frequency. Besides, in highfrequency applications, the number of switching times increases, resulting in significant switching losses. To solve these issues, this paper proposes an improved modulation strategy for the single-phase three-level neutral-point-clamped(NPC) converter in CRM with PFC. By optimizing the discharging strategy and switching state sequence, the switching frequency and its variation range have been efficiently reduced. The detailed performance analysis is also presented regarding the switching frequency, the average switching times, and the effect of voltage gain. A 2 k W prototype is built to verify the effectiveness of the proposed modulation strategy and analysis results. Compared with the totem-pole PFC converter, the switching frequency regulation range of the three-level PFC converter is reduced by 36.48% and the average switching times is reduced by 45.10%. The experimental result also shows a 1.2% higher efficiency for the three-level PFC converter in the full load range.

关键词： Switches Switching frequency Control systems Topology Bridge circuits Inductors Customer relationship management

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

An efficient permutation approach for SbPN-based symmetric block ciphers

引用

Cybersecurity 2024年第2期7卷 113-130页

作者： Mir Nazish M.Tariq Banday Insha Syed Sheena Banday department of electronics and Instrumentation Technology University ofKashmirSrinagar 190006India

It is challenging to devise lightweight cryptographic primitives efficient in both hardware and software that can provide an optimum level of security to diverse Internet of Things applications running on low-end constrained devices.Therefore,an effcient hardware design approach that requires some specific hardware resource may not be effcient if implemented in software.Substitution bit Permutation Network based ciphers such as PRESENT and GIFT are effcient,lightweight cryptographic hardware design approaches.These ciphers introduce confusion and diffu-sion by employing a 4×4 static substitution box and bit permutations.The bit-wise permutation is realised by sim-ple rerouting,which is most cost-effective to implement in hardware,resulting in negligible power consumption.However,this method is highly resource-consuming in software,particularly for large block-sized ciphers,with each single-bit permutation requiring multiple sub-operations.This paper proposes a novel software-based design approach for permutation operation in Substitution bit Permutation Network based ciphers using a bit-banding fea-ture.The conventional permutation using bit rotation and the proposed approach have been implemented,analysed and compared for GIFT and PRESENT ciphers on ARM Cortex-M3-based LPC1768 development platform with KEIL MDK used as an Integrated Development Environment.The real-time performance comparison between conven-tional and the proposed approaches in terms of memory(RAM/ROM)footprint,power,energy and execution time has been carried out using ULINKpro and ULINKplus debug adapters for various code and speed optimisation sce-narios.The proposed approach substantially reduces execution time,energy and power consumption for both PRE-SENT and GIFT ciphers,thus demonstrating the effciency of the proposed method for Substitution bit Permutation Network based symmetric block ciphers.

关键词： Lightweight cryptography PRESENT GIFT SbPN Cortex-M LPC1768 Bit-band memory

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

Bioinspired 3D flexible devices and functional systems

引用

National Science Review 2024年第3期11卷 271-295页

作者： Xu Cheng Zhangming Shen Yihui Zhang Applied Mechanics Laboratory Department of Engineering Mechanics Tsinghua University Laboratory of Flexible electronics Technology Tsinghua University

Flexible devices and functional systems with elaborated three-dimensional(3D) architectures can endow better mechanical/electrical performances, more design freedom, and unique functionalities, when compared to their two-dimensional(2D) counterparts. Such 3D flexible devices/systems are rapidly evolving in three primary directions, including the miniaturization, the increasingly merged physical/artificial intelligence and the enhanced adaptability and capabilities of heterogeneous integration.Intractable challenges exist in this emerging research area, such as relatively poor controllability in the locomotion of soft robotic systems, mismatch of bioelectronic interfaces, and signal coupling in multi-parameter sensing. By virtue of long-time–optimized materials, structures and processes, natural organisms provide rich sources of inspiration to address these challenges, enabling the design and manufacture of many bioinspired 3D flexible devices/systems. In this Review, we focus on bioinspired 3D flexible devices and functional systems, and summarize their representative design concepts, manufacturing methods, principles of structure-function relationship and broad-ranging applications. Discussions on existing challenges, potential solutions and future opportunities are also provided to usher in further research efforts toward realizing bioinspired 3D flexible devices/systems with precisely programmed shapes,enhanced mechanical/electrical performances, and high-level physical/artificial intelligence.

关键词： bioinspired designs biomimetic 3D structures 3D flexible electronics 3D functional systems direct 3D manufacture 2D-to-3D assembly

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

Track-before-detect for bistatic radar based on pseudo-spectrum

引用

Chinese Journal of Aeronautics 2024年第1期37卷 236-246页

作者： Tao HAN Gongjian ZHOU School of electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory of marine Environmental Monitoring and Information Processing Ministry of Industry and Information TechnologyHarbin 150001China

Track-Before-Detect(TBD) is an efficient method to detect dim targets for radars. Conventional TBD usually follows an approximate motion model of the target, which may cause an inaccurate integration of the target energy. A TBD technique on basis of pseudo-spectrum in mixed coordinates adopting an accurate motion model for bistatic radar system is developed in this paper.The predicted position in bistatic polar plane is derived according to a nonlinear function that exactly describes the constant Cartesian velocity motion. Then around the predicted position, a pseudo-spectrum is formulated and its samples are accumulated to the integration frame for energy integration. The evolution of the state and the procedure of accumulation of the target energy are derived elaborately. The superior performance of the proposed method is demonstrated by some simulations.

关键词： Weak target detection Bistatic radar Track-before-detect Pseudo-spectrum Multiframe integration

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

Evaluation of a hepatic biomarker of nutritional imbalance in juvenile red drum(Sciaenops ocellatus) fed 60% soybean meal-based diets using NMR-based metabolomics

引用

Animal Nutrition 2024年第1期16卷 45-61页

作者： Fabio Casu Aaron M.Watson Justin Yost T.Gibson Gaylord Daniel W.Bearden Michael R.Denson marine Resources Research Institute South Carolina Department of Natural Resources Bozeman Fish Technology Center United States Fish and Wildlife Service marine Biochemical Sciences Group Chemical Sciences Division National Institute of Standards and Technology Hollings Marine Laboratory

A 12-week feeding trial with juvenile red drum(Sciaenops ocellatus) fed high-soybean meal(SBM) diets was conducted to investigate a putative biomarker of nutritional imbalance, N-formimino-L-glutamate(FIGLU). Three fishmeal-free, 60% SBM pelleted diets(named B12, Fol, and Met, respectively) were tested to evaluate the effects on growth performance and tissue metabolite profiles of supplementation of vitamin B12(0.012 mg/kg), folate(10 mg/kg), methionine(1 g/kg) respectively, above basal supplementation levels. A fourth SBM-based diet(named B12/Fol/Met) was formulated with a combination of B12, folate, and methionine to attain the above-mentioned target concentrations. A fifth 60% SBM diet(named FWS) with methionine supplementation(1 g/kg above basal supplementation levels), enriched with taurine, lysine and threonine as well as minerals, was also tested. This diet contained formulation targets and additives which have allowed for replacing fishmeal with plant proteins in rainbow trout feeds. Control diets included a fishmeal-based diet(named FM), an unsupplemented basal 60% SBM diet(named SBM60), and a “natural” diet(named N) made up of equal parts of fish(cigar minnows), squid and shrimp as a positive reference for growth performance. Formulated feeds contained approximately 37% total crude protein, approximately 14% total crude lipid and were energetically balanced. Standard growth performance metrics were measured, and tissues(liver, muscle) were collected at week 12 to evaluate diet-induced metabolic changes using nuclear magnetic resonance(NMR)-based metabolomics.Our results show that the FWS diet outperformed all other SBM diets and the FM diet under all performance metrics(P<0.05). FIGLU was not detected in fish fed the N diet but was detected in those fed the SBM diets and the FM diet. Fish fed the FWS diet and the Met diet showed lower hepatic levels of FIGLU compared with the other SBM-based diets(P<0.05), suggesting that among the different supplementation regimes, methionine supplementation was associ

关键词： Aquaculture Metabolomics Nuclear magnetic resonance Red drum Soybean meal N-Formimino-L-glutamate

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

Ag-integrated mixed metallic Co-Fe-Ni-Mn hydroxide composite as advanced electrode for high-performance hybrid supercapacitors

引用

Journal of Energy Chemistry 2024年第1期88卷 579-591,I0013页

作者： Anki Reddy Mule Bhimanaboina Ramulu Shaik Junied Arbaz Anand Kurakula Jae Su Yu department of electronics and Information Convergence Engineering Institute for Wearable Convergence ElectronicsKyung Hee UniversityYongin-siGyeonggi-do 17104Republic of Korea

Direct growth of redox-active noble metals and rational design of multifunctional electrochemical active materials play crucial roles in developing novel electrode materials for energy storage devices.In this regard,silver(Ag)has attracted great attention in the design of efficient electrodes.Inspired by the house/building process,which means electing the right land,it lays a strong foundation and building essential columns for a complex structure.Herein,we report the construction of multifaceted heterostructure cobalt-iron hydroxide(CFOH)nanowires(NWs)@nickel cobalt manganese hydroxides and/or hydrate(NCMOH)nanosheets(NSs)on the Ag-deposited nickel foam and carbon cloth(i.e.,Ag/NF and Ag/CC)substrates.Moreover,the formation and charge storage mechanism of Ag are described,and these contribute to good conductive and redox chemistry features.The switching architectural integrity of metal and redox materials on metallic frames may significantly boost charge storage and rate performance with noticeable drop in resistance.The as-fabricated Ag@CFOH@NCMOH/NF electrode delivered superior areal capacity value of 2081.9μA h cm^(-2)at 5 mA cm^(-2).Moreover,as-assembled hybrid cell based on NF(HC/NF)device exhibited remarkable areal capacity value of 1.82 mA h cm^(-2)at 5 mA cm^(-2)with excellent rate capability of 74.77%even at 70 mA cm^(-2)Furthermore,HC/NF device achieved maximum energy and power densities of 1.39 mW h cm^(-2)and 42.35 mW cm^(-2),respectively.To verify practical applicability,both devices were also tested to serve as a self-charging station for various portable electronic devices.

关键词： Current collectors Redox-active silver Transition metal-hydroxides Electrochemical performance Hybrid supercapacitor

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

Findings on three endocommensal scuticociliates(Protista,Ciliophora)from freshwater mollusks,including their morphology and molecular phylogeny with descriptions of two new species

引用

marine Life Science & Technology 2024年第2期6卷 212-235页

作者： Tao Li Tengyue Zhang Mingjian Liu Zhe Zhang Jiachen Zhang Junhua Niu Xiangrui Chen Saleh A.Al‑Farraj Weibo Song Institute of Evolution and marine Biodiversity Ocean University of China and Key Laboratory of Evolution and Marine Biodiversity(Ministry of Education)Qingdao 266003China The Key Laboratory of Zoological Systematics and Application College of Life SciencesHebei UniversityBaoding 071002China College of marine Life Sciences Ocean University of ChinaQingdao 266003China School of marine Sciences Ningbo UniversityNingbo 315800China Zoology department College of ScienceKing Saud University11451 RiyadhSaudi Arabia Laboratory for marine Biology and Biotechnology Laoshan LaboratoryQingdao 266237China

Species of the ciliate genera Myxophyllum and Conchophthirus are found as endocommensals of terrestrial and freshwater mollusks,respectively.So far,there have been few studies of these genera and morphological data for most members are often incomplete.In the present work,two new species,Myxophyllum weishanense sp.***.and Conchophthirus paracurtus sp.nov.,and a known species,Conchophthirus lamellidens,were isolated from hosts in Lake Weishan Wetland,China.Taxonomic studies indicate that M.weishanense sp.***.can be recognized mainly by the combination of about 60 somatic kineties on both ventral and dorsal sides and the presence of caudal cilia.Conchophthirus paracurtus sp.***.differs from congeners in its body shape and size,having a glabrous area on the posterior right side,and having fewer somatic kineties.In addition,differences in their ITS2(Internally Transcribed Spacer 2)secondary structures support the discrimination of the two new species from their highly similar congeners.An improved diagnosis for the poorly known species,C.lamel-lidens is also provided.Phylogenetic analyses reveal that members of the genus Myxophyllum belong to a fully supported clade that is sister to a large,poorly supported clade consisting of Hemispeiridae,Ancistridae,and several lineages of the nonmonophyletic Cyclidiidae.The Myxophyllum clade also includes Protophyra ovicola JQ956552,a possible misidenti-fication.Sequences of the two new Conchophthirus species cluster with other congeners in a fully supported clade that is unrelated to either the‘typical’thigmotrichs or to pleuronematids,thus conflicting with the traditional classification,and may represent an orphan scuticociliate lineage.

关键词： Ciliates Endocommensal ITS2 secondary structure Mollusks New taxa Wetland

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

From germline genome to highly fragmented somatic genome:genome-wide DNA rearrangement during the sexual process in ciliated protists

引用

marine Life Science & Technology 2024年第1期6卷 31-49页

作者： Liping Lyu Xue Zhang Yunyi Gao Tengteng Zhang Jinyu Fu Naomi A.Stover Feng Gao Key Laboratory of Evolution&marine Biodiversity(Ministry of Education) and Institute of Evolution&Marine BiodiversityOcean University of ChinaQingdao 266003China department of Biology Bradley UniversityPeoriaIL 61625USA Laoshan Laboratory Qingdao 266237China

Genomes are incredibly dynamic within diverse eukaryotes and programmed genome rearrangements(PGR)play important roles in generating genomic diversity.However,genomes and chromosomes in metazoans are usually large in size which prevents our understanding of the origin and evolution of PGR.To expand our knowledge of genomic diversity and the evolutionary origin of complex genome rearrangements,we focus on ciliated protists(ciliates).Ciliates are single-celled eukaryotes with highly fragmented somatic chromosomes and massively scrambled germline genomes.PGR in ciliates occurs extensively by removing massive amounts of repetitive and selfish DNA elements found in the silent germline genome dur-ing development of the somatic genome.We report the partial germline genomes of two spirotrich ciliate species,namely Strombidium cf.sulcatum and Halteria grandinella,along with the most compact and highly fragmented somatic genome for S.cf.sulcatum.We provide the first insights into the genome rearrangements of these two species and compare these features with those of other ciliates.Our analyses reveal:(1)DNA sequence loss through evolution and during PGR in S.cf.sulcatum has combined to produce the most compact and efficient nanochromosomes observed to date;(2)the compact,transcriptome-like somatic genome in both species results from extensive removal of a relatively large number of shorter germline-specific DNA sequences;(3)long chromosome breakage site motifs are duplicated and retained in the somatic genome,revealing a complex model of chromosome fragmentation in spirotrichs;(4)gene scrambling and alternative pro-cessing are found throughout the core spirotrichs,offering unique opportunities to increase genetic diversity and regulation in this group.

关键词： Alternative processing Ciliates Gene scrambling Genome rearrangement Germline genome Somatic genome

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

Interfacial friction effects on sealing performances of elastomer packer

引用

Petroleum Science 2024年第3期21卷 2037-2047页

作者： Peng-Cheng Wang Ming-Hui Chen Jim Jenkinson Yong-Xin Song Li Sun department of Mechanical Engineering University of Houston Guren Nanomaterials department of marine Engineering Dalian Maritime University

Elastomer sealing performance is of critical importance for downhole tools application including the use of fracturing(Frac) plugs during multi-stage hydraulic fracking. In practice sealing performances of such plugs are normally evaluated through pressure tests, and in numerical simulation studies, maximum contact stress, average contact stress and contact length data are used to determine sealing quality between a packer and casing. In previous studies, the impact of friction forces on sealing performance is often overlooked. This work aims to fill this knowledge gap in determining the influence of friction forces on elastomer packer sealing performances. We first determined the most appropriate constitutive hyperelastic model for the elastomers used in frac plug. Then we compared analytical calculation results with Finite Element Analysis simulation using a simplified tubular geometry and showed the significant influences on interfacial friction on elastomer packer stress distribution, deformation, and contact stress after setting. With the demonstration of validity of FEA method, we conducted systematic numerical simulation studies to show how the interfacial friction coefficients can affect the maximum contact stress, average contact stress, contact stress distribution, and maximum mises stress for an actual packer used in plug products. In addition, we also demonstrated how the groove in a packer can affect packer deformation and evolvement during setting with the consideration of interfacial stress. This study underscores the critical role that friction forces play in Frac plug performance and provides a new dimension for optimizing packer design by controlling interfacial interactions at the packer contact surfaces.

关键词： Elastomer seal Friction Sealing performance Contact stress

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

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：