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Microstructure and thermal properties of dissimilar M300–CuCr1Zr alloys by multi-material laser-based powder bed fusion 被引量:1
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作者 Xiaoshuang Li Dmitry Sukhomlinov Zaiqing Que 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期118-128,共11页
Multi-material laser-based powder bed fusion (PBF-LB) allows manufacturing of parts with 3-dimensional gradient and additional functionality in a single step. This research focuses on the combination of thermally-cond... Multi-material laser-based powder bed fusion (PBF-LB) allows manufacturing of parts with 3-dimensional gradient and additional functionality in a single step. This research focuses on the combination of thermally-conductive CuCr1Zr with hard M300 tool steel.Two interface configurations of M300 on CuCr1Zr and CuCr1Zr on M300 were investigated. Ultra-fine grains form at the interface due to the low mutual solubility of Cu and steel. The material mixing zone size is dependent on the configurations and tunable in the range of0.1–0.3 mm by introducing a separate set of parameters for the interface layers. Microcracks and pores mainly occur in the transition zone.Regardless of these defects, the thermal diffusivity of bimetallic parts with 50vol% of CuCr1Zr significantly increases by 70%–150%compared to pure M300. The thermal diffusivity of CuCr1Zr and the hardness of M300 steel can be enhanced simultaneously by applying the aging heat treatment. 展开更多
关键词 multi-material additive manufacturing laser-based powder bed fusion thermal diffusivity dissimilar metals copper alloy
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Semantic segmentation-based semantic communication system for image transmission
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作者 Jiale Wu Celimuge Wu +4 位作者 Yangfei Lin Tsutomu Yoshinaga Lei Zhong Xianfu Chen Yusheng Ji 《Digital Communications and Networks》 SCIE CSCD 2024年第3期519-527,共9页
With the rapid development of artificial intelligence and the widespread use of the Internet of Things, semantic communication, as an emerging communication paradigm, has been attracting great interest. Taking image t... With the rapid development of artificial intelligence and the widespread use of the Internet of Things, semantic communication, as an emerging communication paradigm, has been attracting great interest. Taking image transmission as an example, from the semantic communication's view, not all pixels in the images are equally important for certain receivers. The existing semantic communication systems directly perform semantic encoding and decoding on the whole image, in which the region of interest cannot be identified. In this paper, we propose a novel semantic communication system for image transmission that can distinguish between Regions Of Interest (ROI) and Regions Of Non-Interest (RONI) based on semantic segmentation, where a semantic segmentation algorithm is used to classify each pixel of the image and distinguish ROI and RONI. The system also enables high-quality transmission of ROI with lower communication overheads by transmissions through different semantic communication networks with different bandwidth requirements. An improved metric θPSNR is proposed to evaluate the transmission accuracy of the novel semantic transmission network. Experimental results show that our proposed system achieves a significant performance improvement compared with existing approaches, namely, existing semantic communication approaches and the conventional approach without semantics. 展开更多
关键词 Semantic Communication Semantic segmentation Image transmission Image compression Deep learning
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Stiffness of In-Situ Formed Interleaving Polymeric Nanofiber-Epoxy Nanocomposites
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作者 Farzin Javanshour Kaan Bilge +1 位作者 Abdul Bari Abdul Raheman Melih Papila 《Open Journal of Composite Materials》 2024年第4期147-157,共11页
This study proposes a facile, but precise method to back-calculate the effective modulus of nanocomposite interleaving plies. Adaptation of a conventional dry-reinforcement resin film infusion (RFI) approach allows in... This study proposes a facile, but precise method to back-calculate the effective modulus of nanocomposite interleaving plies. Adaptation of a conventional dry-reinforcement resin film infusion (RFI) approach allows interleaving neat epoxy layers (NE) with the epoxy-infused nanofibrous plies (XE) of constant thickness. The final cured nanocomposite laminate thus has the form (NE/XE)n, where “n” denotes the number of the repeats and enables clear distinction of the nanocomposite interlayers through the thickness. Mechanical testing of neat epoxy and laminated nanocomposite specimens can be coupled with the classical lamination theory for back-calculating in-plane elastic modulus of the individual epoxy-infused nanofibrous plies (EXE). Finite element analysis (FEA) and testing the laminated nanocomposite subject to flexural loading (3-point bending) are proposed to validate the analytically back-calculated EXE. It is shown that the FEA prediction incorporating EXE and testing for flexural modulus of (NE/XE)20 laminated nanocomposites correlate well and the results are within 5%. This finding suggests that the back-calculation scheme reported herein would be attractive for accurately determining the properties of an individual nanocomposite building block layer. The proposed framework is beneficial for modelling laminated structural composites incorporating XE-like nanocomposite interlayers. 展开更多
关键词 Lamination Theory Resin Film Infusion Electrospun Nanofibers Mechanical Properties
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NOMA-Based Spectrum Sensing for Satellite-Terrestrial Communication 被引量:2
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作者 Tianheng Xu Yinjun Xu +2 位作者 Ting Zhou Xianfu Chen Honglin Hu 《China Communications》 SCIE CSCD 2023年第4期227-242,共16页
With the continuous development of wireless communication technology,the number of access devices continues to soar,which poses a grate challenge to the already scarce spectrum resources.Meanwhile,6G will be an era of... With the continuous development of wireless communication technology,the number of access devices continues to soar,which poses a grate challenge to the already scarce spectrum resources.Meanwhile,6G will be an era of air-space-terrestrial-sea integration,and satellite spectrum resources are also very tight in the context of giant constellations.In this paper,we propose a Non-Orthogonal Multiple Access(NOMA)based spectrum sensing scheme for the future satellite-terrestrial communication scenarios,and design the transceiver from uplink and downlink scenarios,respectively.In order to better identify the user's transmission status,we obtain the feature values of each user through feature detection to make decision.We combine these two technologies to design the transceiver architecture and deduce the threshold value of feature detection in the satellite-terrestrial communication scenario.Simulations are performed in each scenario,and the results illustrate that the proposed scheme combining NOMA and spectrum sensing can greatly improve the throughput with a similar detection probability as Orthogonal Multiple Access(OMA). 展开更多
关键词 NOMA spectrum sensing feature detection satellite-terrestrial communication
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瑞氏木霉木糖代谢关键酶基因在不同碳源条件下的表达 被引量:2
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作者 汪天虹 MerjaPenttil 高培基 《微生物学报》 CAS CSCD 北大核心 1999年第6期503-509,共7页
用20 种不同的碳源( 包括单一碳源和混合碳源) 分别培养瑞氏木霉( Trichodermareesei)QM9414 。通过一系列Northern 杂交分析检测瑞氏木霉木糖还原酶(XR) ,木糖醇脱氢酶(XDH) 以及转醛... 用20 种不同的碳源( 包括单一碳源和混合碳源) 分别培养瑞氏木霉( Trichodermareesei)QM9414 。通过一系列Northern 杂交分析检测瑞氏木霉木糖还原酶(XR) ,木糖醇脱氢酶(XDH) 以及转醛醇酶(TAL) m RNA 的表达情况。实验结果证实,槐糖和木二糖是xr 和xdh 表达的强诱导物,阿拉伯糖和乳糖也有较强的诱导作用。葡萄糖在培养基中的存在阻遏该二基因的表达。当葡萄糖耗尽以后,培养基中不存在任何诱导物的情况下,xr 和xdh 以一定的基础水平进行转录。相比较,tal 展开更多
关键词 瑞氏木霉 基因表达 XR XDH TAL 木糖
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带有木糖还原酶基因和木糖醇脱氢酶基因的重组酿酒酵母的构建 被引量:5
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作者 汪天虹 MerjaPentil 李波 《菌物系统》 CSCD 北大核心 1999年第3期311-315,共5页
采用双载体系统,将携带有瑞氏木霉木糖醇脱氢酶基因的表达质粒pAJ401-Xdh1转化已带有树干毕赤氏酵母木糖还原酶基因的重组酿酒酵母H475,构建了同时带有毕赤氏酵母木糖还原酶基因和瑞氏木霉木糖醇脱氢酶基因的重组酿酒酵母HX1。研究... 采用双载体系统,将携带有瑞氏木霉木糖醇脱氢酶基因的表达质粒pAJ401-Xdh1转化已带有树干毕赤氏酵母木糖还原酶基因的重组酿酒酵母H475,构建了同时带有毕赤氏酵母木糖还原酶基因和瑞氏木霉木糖醇脱氢酶基因的重组酿酒酵母HX1。研究了重组酿酒酵母HX1对木糖的转化利用情况。 展开更多
关键词 重组酿酒酵母 木糖还原酶 木糖醇脱氢酶
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Sprayformed Hot Work Steels for Rapid Tooling 被引量:5
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作者 Yunfeng Yang Simo-Pekka Hannula 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2003年第z1期169-172,共4页
The present work compares microstructures of hot work steels made by different processes, that is, by sprayforming,by casting, and a commercially supplied H13 steel. Material benefits are recognized by sprayforming ho... The present work compares microstructures of hot work steels made by different processes, that is, by sprayforming,by casting, and a commercially supplied H13 steel. Material benefits are recognized by sprayforming hot working tools such as die inserts for hot forging. The sprayformed hot work steels present a fine and homogeneous microstructure,which implies that, at a similar toughness level, the sprayformed steel can be higher alloyed, so that the thermal fatigue and wear resistance at elevated temperatures can be improved. A series of steels with higher vanadium content than commercial hot work steels are developed. There are no segregation and carbide network problems usually encountered in conventional ingot/forging processed high-vanadium steels. Microstructure and hardness of the new sprayformed steels are studied under different heat treatment conditions. It is justified that these sprayformed steels can be directly used for tooling without high temperature hardening. Sprayforming the tool steels onto a precision ceramic mould is demonstrated to extend the technoeconomical benefits, so that a net shape production tool can be rapidly made.Features of the rapid tooling process are also discussed. 展开更多
关键词 RAPID tooling Sprayforming HOT working steel DIE INSERT
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相思木浆用于文化用纸生产时的滤水性能和留着性能 被引量:1
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作者 文向丰 张美云 +1 位作者 胥成龙 Elias Retulainen 《黑龙江造纸》 2003年第4期17-19,共3页
对来自印度尼西亚的相思木 (Acacia)浆与混合阔叶木浆和来自北欧的桦木浆进行对比分析 ,以期获得用于文化用纸生产时湿部的潜在滤水、留着性能及相关的手抄片性能 ,这些性能比较均基于恒定的抗张强度水平。相思木浆被证明拥有在文化用... 对来自印度尼西亚的相思木 (Acacia)浆与混合阔叶木浆和来自北欧的桦木浆进行对比分析 ,以期获得用于文化用纸生产时湿部的潜在滤水、留着性能及相关的手抄片性能 ,这些性能比较均基于恒定的抗张强度水平。相思木浆被证明拥有在文化用纸生产中至关重要的光散射能力、湿部成形和填料留着能力方面的优越性。需要改进的地方是 :它的滤水速率和湿纸幅强度较低 ,这些将是现代高速纸机湿部的瓶颈所在。相比之下 ,桦木浆具有较快的滤水速率和较高的湿部固含量 。 展开更多
关键词 相思木浆 文化用纸生产 滤水性能 留着性能 混合阔叶木浆 运动型带式抄片器
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Diarrhoea-predominant irritable bowel syndrome distinguishable by 16S rRNA gene phylotype quantification 被引量:26
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作者 Anna Lyra Teemu Rinttil +6 位作者 Janne Nikkil Lotta Krogius-Kurikka Kajsa Kajander Erja Malinen Jaana Mtt Laura Mkel Airi Palva 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第47期5936-5945,共10页
AIM:To study whether selected bacterial 16S ribosomal RNA(rRNA)gene phylotypes are capable of disting- uishing irritable bowel syndrome(IBS). METHODS:The faecal microbiota of twenty volunteers with IBS,subdivided into... AIM:To study whether selected bacterial 16S ribosomal RNA(rRNA)gene phylotypes are capable of disting- uishing irritable bowel syndrome(IBS). METHODS:The faecal microbiota of twenty volunteers with IBS,subdivided into eight diarrhoea-predominant (IBS-D),eight constipation-predominant(IBS-C)and four mixed symptom-subtype(IBS-M)IBS patients,and fifteen control subjects,were analysed at three time-points with a set of fourteen quantitative real-timepolymerase chain reaction assays.All assays targeted 16S rRNA gene phylotypes putatively associated with IBS,based on 16S rRNA gene library sequence analysis. The target phylotypes were affiliated with Actinobac-teria,Bacteroidetes and Firmicutes.Eight of the target phylotypes had less than 95%similarity to cultured bacterial species according to their 16S rRNA gene sequence.The data analyses were made with repeated-measures ANCOVA-type modelling of the data and principle component analysis(PCA)with linear mixed-effects models applied to the principal component scores. RESULTS:Bacterial phylotypes Clostridium cocleatum 88%,Clostridium thermosuccinogenes 85%,Coprobacillus catenaformis 91%,Ruminococcus bromii-like, Ruminococcus torques 91%,and R.torques 93%were detected from all samples analysed.A multivariate analysis of the relative quantities of all 14 bacterial 16S rRNA gene phylotypes suggested that the intestinal microbiota of the IBS-D patients differed from other sample groups.The PCA on the first principal component(PC1),explaining 30.36%of the observed variation in the IBS-D patient group,was significantly altered from all other sample groups(IBS-D vs control, P=0.01;IBS-D vs IBS-M,P=0.00;IBS-D vs IBS-C, P=0.05).Significant differences were also observed in the levels of distinct phylotypes using relative values in proportion to the total amount of bacteria.A phy- lotype with 85%similarity to C.thermosuccinogenes was quantified in significantly different quantities among the IBS-D and control subjects(-4.08±0.90 vs -3.33±1.16,P=0.04)and IBS-D and IBS-M subjects (-4.08±0.90 vs-3.08±1.38,P=0.05).Furthermore,a phylotype with 94%similarity to R.torques was more prevalent in IBS-D patients'intestinal micro- biota than in that of control subjects(-2.43±1.49 vs -4.02±1.63,P=0.01).A phylotype with 93%simi- larity to R.torques was associated with control sam- ples when compared with IBS-M(-2.41±0.53 vs -2.92±0.56,P=0.00).Additionally,a R.bromii-like phylotype was associated with IBS-C patients in com- parison to control subjects(-1.61±1.83 vs-3.69± 2.42,P=0.01).All of the above mentioned phylotype specific alterations were independent of the effect of time. CONCLUSION:Significant phylotype level alterationsin the intestinal microbiotas of IBS patients were observed,further emphasizing the possible contribution of the gastrointestinal microbiota in IBS. 展开更多
关键词 Irritable bowel syndrome Diarrhoea-predominant irritable bowel syndrome Intestinal microbiota Quantitative real-time polymerase chain reaction 16S ribosomal RNA
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Clustering Structure Analysis in Time-Series Data With Density-Based Clusterability Measure 被引量:6
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作者 Juho Jokinen Tomi Raty Timo Lintonen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第6期1332-1343,共12页
Clustering is used to gain an intuition of the struc tures in the data.Most of the current clustering algorithms pro duce a clustering structure even on data that do not possess such structure.In these cases,the algor... Clustering is used to gain an intuition of the struc tures in the data.Most of the current clustering algorithms pro duce a clustering structure even on data that do not possess such structure.In these cases,the algorithms force a structure in the data instead of discovering one.To avoid false structures in the relations of data,a novel clusterability assessment method called density-based clusterability measure is proposed in this paper.I measures the prominence of clustering structure in the data to evaluate whether a cluster analysis could produce a meaningfu insight to the relationships in the data.This is especially useful in time-series data since visualizing the structure in time-series data is hard.The performance of the clusterability measure is evalu ated against several synthetic data sets and time-series data sets which illustrate that the density-based clusterability measure can successfully indicate clustering structure of time-series data. 展开更多
关键词 CLUSTERING EXPLORATORY data analysis time-series UNSUPERVISED LEARNING
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MR电影成像验证早期家族性扩张型心肌病的状态参数 被引量:7
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作者 J.R.Koikkalainen M.Antila +4 位作者 J.M.P.Ltjnen T.Heli K.Lauerma S.M.Kivist 周路遥 《国际医学放射学杂志》 2008年第A06期497-497,共1页
目的运用MRI显示核纤层蛋白A/C基因(LMNA)突变携带者心脏解剖结构和功能早期变化的特征,并建立一种分析和显示结果的工具。
关键词 MR电影成像 核纤层蛋白 携带者 状态参数 经胸超声心动图 功能指数 左心室增大 室壁厚度 亚临床
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Effect of weld microstructure on brittle fracture initiation in the thermallyaged boiling water reactor pressure vessel head weld metal 被引量:2
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作者 Noora Hytönen Zai-qing Que +4 位作者 Pentti Arffman Jari Lydman Pekka Nevasmaa Ulla Ehrnstén Pål Efsing 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第5期867-876,共10页
Effects of the weld microstructure and inclusions on brittle fracture initiation are investigated in a thermally aged ferritic high-nickel weld of a reactor pressure vessel head from a decommissioned nuclear power pla... Effects of the weld microstructure and inclusions on brittle fracture initiation are investigated in a thermally aged ferritic high-nickel weld of a reactor pressure vessel head from a decommissioned nuclear power plant.As-welded and reheated regions mainly consist of acicular and polygonal ferrite,respectively.Fractographic examination of Charpy V-notch impact toughness specimens reveals large inclusions(0.5-2.5μm)at the brittle fracture primary initiation sites.High impact energies were measured for the specimens in which brittle fracture was initiated from a small inclusion or an inclusion away from the V-notch.The density,geometry,and chemical composition of the primary initiation inclusions were investigated.A brittle fracture crack initiates as a microcrack either within the multiphase oxide inclusions or from the debonded interfaces between the uncracked inclusions and weld metal matrix.Primary fracture sites can be determined in all the specimens tested in the lower part of the transition curve at and below the 41-J reference impact toughness energy but not above the mentioned value because of the changes in the fracture mechanism and resulting changes in the fracture appearance. 展开更多
关键词 reactor pressure vessel brittle fracture weld microstructure thermal aging
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Self-Learning of Multivariate Time Series Using Perceptually Important Points 被引量:2
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作者 Timo Lintonen Tomi Raty 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第6期1318-1331,共14页
In machine learning,positive-unlabelled(PU)learning is a special case within semi-supervised learning.In positiveunlabelled learning,the training set contains some positive examples and a set of unlabelled examples fr... In machine learning,positive-unlabelled(PU)learning is a special case within semi-supervised learning.In positiveunlabelled learning,the training set contains some positive examples and a set of unlabelled examples from both the positive and negative classes.Positive-unlabelled learning has gained attention in many domains,especially in time-series data,in which the obtainment of labelled data is challenging.Examples which originate from the negative class are especially difficult to acquire.Self-learning is a semi-supervised method capable of PU learning in time-series data.In the self-learning approach,observations are individually added from the unlabelled data into the positive class until a stopping criterion is reached.The model is retrained after each addition with the existent labels.The main problem in self-learning is to know when to stop the learning.There are multiple,different stopping criteria in the literature,but they tend to be inaccurate or challenging to apply.This publication proposes a novel stopping criterion,which is called Peak evaluation using perceptually important points,to address this problem for time-series data.Peak evaluation using perceptually important points is exceptional,as it does not have tunable hyperparameters,which makes it easily applicable to an unsupervised setting.Simultaneously,it is flexible as it does not make any assumptions on the balance of the dataset between the positive and the negative class. 展开更多
关键词 Positive-unlabelled(PU) learning SELF-LEARNING stopping criterion time series
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Elevated pro-inflammatory and lipotoxic mucosal lipids characterise irritable bowel syndrome 被引量:6
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作者 Kajsa Kajander Eveliina Myllyluoma +7 位作者 Sinikka Kyrnpalo Martin Rasmussen Pentti Sipponen Ismo Mattila Tuulikki Seppnen-Laakso Heikki Vapaatalo Matej Orei Riitta Korpela 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第48期6068-6074,共7页
AIM: To investigate the pathophysiology of irritable bowel syndrome (IBS) by comparing the global mucosal metabolic profiles of IBS patients with those of healthy controls. METHODS: Fifteen IBS patients fulfilling... AIM: To investigate the pathophysiology of irritable bowel syndrome (IBS) by comparing the global mucosal metabolic profiles of IBS patients with those of healthy controls. METHODS: Fifteen IBS patients fulfilling the Rome II criteria, and nine healthy volunteers were included in the study. A combined lipidomics (UPLC/MS) and metabolomics (GC × GC-TOF) approach was used to achieve global metabolic profiles of mucosal biopsies from the ascending colon. RESULTS: Overall, lipid levels were elevated in patients with IBS. The most significant upregulation was seen for pro-inflammatory lysophosphatidylcholines. Other lipid groups that were significantly upregulated in IBS patients were lipotoxic ceramides, glycosphingolipids, and di-and triacylglycerols. Among the meo tabolites, the cyclic ester 2(3H)-furanone was almost 14-fold upregulated in IBS patients compared to healthy subjects (P = 0.03). CONCLUSION: IBS mucosa is characterised by a distinct pro-inflammatory and lipotoxic metabolic profile. Especially, there was an increase in several lipid species such as lysophospholipids and ceramides. 展开更多
关键词 Functional gastrointestinal diseases Irritable bowel syndrome HISTOPATHOLOGY
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Probiotic Lactobacillus rhamnosus downregulates FCER1 and HRH4 expression in human mast cells 被引量:3
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作者 Anna Oksaharju Matti Kankainen +4 位作者 Riina A Kekkonen Ken A Lindstedtt Petri T Kovanen Riitta Korpela Minja Miettinen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第6期750-759,共10页
AIM:To investigate the effects of four probiotic bacteria and their combination on human mast cell gene expression using microarray analysis.METHODS:Human peripheral-blood-derived mast cells were stimulated with Lacto... AIM:To investigate the effects of four probiotic bacteria and their combination on human mast cell gene expression using microarray analysis.METHODS:Human peripheral-blood-derived mast cells were stimulated with Lactobacillus rhamnosus (L.rhamnosus) GG (LGG),L.rhamnosus Lc705 (Lc705),Propionibacterium freudenreichii ssp.shermanii JS (PJS) and Bifidobacterium animalis ssp.lactis Bb12 (Bb12) and their combination for 3 or 24 h,and were subjected to global microarray analysis using an Affymetrix GeneChip Human Genome U133 Plus 2.0 Array.The gene expression differences between unstimulated and bacteria-stimulated samples were further analyzed with GOrilla Gene Enrichment Analysis and Visualization Tool and MeV Multiexperiment Viewer-tool.RESULTS:LGG and Lc705 were observed to suppress genes that encoded allergy-related high-affinity IgE receptor subunits α and γ (FCER1A and FCER1G,respectively) and histamine H4 receptor.LGG,Lc705 and the combination of four probiotics had the strongest effect on the expression of genes involved in mast cell immune system regulation,and on several genes that encoded proteins with a pro-inflammatory impact,such as interleukin (IL)-8 and tumour necrosis factor alpha.Also genes that encoded proteins with anti-inflammatory functions,such as IL-10,were upregulated.CONCLUSION:Certain probiotic bacteria might diminish mast cell allergy-related activation by downregulation of the expression of high-affinity IgE and histamine receptor genes,and by inducing a pro-inflammatory response. 展开更多
关键词 Probiotic bacteria Mast cells MICROARRAY ALLERGY IgE receptor
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Time-Critical Tasks Implementation in MEC Based Multi-Robot Cooperation Systems 被引量:2
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作者 Rui Yin Yineng Shen +2 位作者 Huawei Zhu Xianfu Chen Celimuge Wu 《China Communications》 SCIE CSCD 2022年第4期199-215,共17页
Mobile edge computing(MEC) deployment in a multi-robot cooperation(MRC) system is an effective way to accomplish the tasks in terms of energy consumption and implementation latency. However, the computation and commun... Mobile edge computing(MEC) deployment in a multi-robot cooperation(MRC) system is an effective way to accomplish the tasks in terms of energy consumption and implementation latency. However, the computation and communication resources need to be considered jointly to fully exploit the advantages brought by the MEC technology. In this paper, the scenario where multi robots cooperate to accomplish the time-critical tasks is studied, where an intelligent master robot(MR) acts as an edge server to provide services to multiple slave robots(SRs) and the SRs are responsible for the environment sensing and data collection. To save energy and prolong the function time of the system, two schemes are proposed to optimize the computation and communication resources, respectively. In the first scheme, the energy consumption of SRs is minimized and balanced while guaranteeing that the tasks are accomplished under a time constraint. In the second scheme, not only the energy consumption, but also the remaining energies of the SRs are considered to enhance the robustness of the system. Through the analysis and numerical simulations, we demonstrate that even though the first policy may guarantee the minimization on the total SRs’ energy consumption, the function time of MRC system by the second scheme is longer than that by the first one. 展开更多
关键词 cooperative robots mobile edge computing energy consumption resource management
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高速喷墨打印纸涂层表面性能研究 被引量:2
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作者 Author John Kettle Taina Lamminm aki +1 位作者 Patrick Gane 许英(编译) 《中国印刷与包装研究》 CAS 2011年第1期68-70,共3页
在印刷领域,喷墨打印作为一种非接触式的打印方式,其市场份额正在逐渐上升。喷墨打印可用于家庭、办公,并在3D、电子和生物材料印刷方面有很大潜力。在高速喷墨打印中广泛应用的两种墨滴成形技术是,连续喷墨技术(CIJ)和按需喷墨技术(DOD... 在印刷领域,喷墨打印作为一种非接触式的打印方式,其市场份额正在逐渐上升。喷墨打印可用于家庭、办公,并在3D、电子和生物材料印刷方面有很大潜力。在高速喷墨打印中广泛应用的两种墨滴成形技术是,连续喷墨技术(CIJ)和按需喷墨技术(DOD)。按照油墨的基质划分,喷墨打印机所用的油墨可分为水性油墨、溶剂型油墨、相变油墨和紫外光固化油墨;按着色剂划分,可分为颜料型和染料型油墨。油墨固着时会与纸基发生多种反应,这些反应与着色剂的固着和油墨液相的运动有关,会影响印品的质量。 展开更多
关键词 打印纸 喷墨打印机 性能 涂层 喷墨技术 打印方式 市场份额 生物材料
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多层柔性衬底电路板的低成本丝网印刷 被引量:1
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作者 Tuomo Jaakola Markku Lahti +4 位作者 Jarno Petj Kari Kautio Kari Rnk Jaakko Lenkkeri 胡新颖 《中国印刷与包装研究》 CAS 2009年第3期74-76,共3页
当大批量生产多层聚合物基厚膜电路板时需要低成本的印刷技术。对于有超过6层导电层且不平滑的表面来说,丝网印刷是一个便宜、便捷的选择。为了研究丝网印刷技术的可行性,本研究在不同衬底材料的表面,如聚碳酸酯(PC)、聚酯(PET)、聚酰亚... 当大批量生产多层聚合物基厚膜电路板时需要低成本的印刷技术。对于有超过6层导电层且不平滑的表面来说,丝网印刷是一个便宜、便捷的选择。为了研究丝网印刷技术的可行性,本研究在不同衬底材料的表面,如聚碳酸酯(PC)、聚酯(PET)、聚酰亚胺(PI)和液晶聚合物(LCP),使用同样的印刷分辨率,常规的厚膜网版印刷,通过丝网的网孔在衬底上形成精细图形。最后,研究在双层PI衬底(拥有2层导体层,在导体层的两侧有1层绝缘层覆盖板基孔)上的印刷。丝网印刷的导体材料是银基纳米颗粒油墨,介质层是聚酰亚胺基材料。许多变量是妨碍这种经济适用技术大规模生产应用的影响因素。例如,如果固化温度超过200℃,聚酰亚胺基板的稳定性就成为大问题。在本实验中,如果印刷面积小,层与层之间的对齐公差是允许的。然而,在印刷进行一段时间后,层与层之间的平整度会变差。测试用纳米粒子油墨是一种很好的导电系统,但是,当固化温度从230℃降低到200℃时,生产效率会受到极大影响。另一种实现多层结构的方法是层压法。本研究选择PET和PC层,重点是处理沉积胶层的PET层和片材的复合过程。多层结构中的板基孔和导线通过常规厚膜网印解决。先打孔,然后采用厚膜网印填补,最后印刷表面。层与层之间的黏合精度和对准精度<±15μm。 展开更多
关键词 多层衬底 丝网印刷 电路板 胶黏剂
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利用废纸等加工黏胶再生纤维生产技术 被引量:1
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作者 《中华纸业》 CAS 2018年第22期71-72,共2页
本刊讯(VTT消息)芬兰国家技术研究中心(V T T)近日与多家单位共同开发出多项废弃纸制品及衣物等可循环利用技术,通过这一系列新技术手段,可将废纸、硬纸盒、旧衣料、劣质棉、木基纤维等再造成黏胶型再生纤维,可以回收利用于纺织行业,整... 本刊讯(VTT消息)芬兰国家技术研究中心(V T T)近日与多家单位共同开发出多项废弃纸制品及衣物等可循环利用技术,通过这一系列新技术手段,可将废纸、硬纸盒、旧衣料、劣质棉、木基纤维等再造成黏胶型再生纤维,可以回收利用于纺织行业,整个过程不使用传统的二硫化碳等原料,不会对环境造成污染。这一研究项目始于2 016年,有芬兰国家技术研究中心、阿尔托大学、赫尔辛基大学等多家机构参与,得到了欧盟以及芬兰多个城市的资助。目前,研究人员正在探讨这些新技术的商业化应用,第一家采用相关技术的工厂正在规划中。 展开更多
关键词 生产技术 再生纤维 芬兰国家技术研究中心 黏胶 废纸 加工 循环利用技术 商业化应用
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Fast Converging Series for Riemann Zeta Function 被引量:1
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作者 Hannu Olkkonen Juuso T. Olkkonen 《Open Journal of Discrete Mathematics》 2012年第4期131-133,共3页
Riemann zeta function has a key role in number theory and in its applications. In this paper we present a new fast converging series for . Applications of the series include the computation of the and recursive comput... Riemann zeta function has a key role in number theory and in its applications. In this paper we present a new fast converging series for . Applications of the series include the computation of the and recursive computation of , and generally . We discuss on the production of irrational number sequences e.g. for encryption coding and zeta function maps for analysis and synthesis of log-time sampled signals. 展开更多
关键词 RIEMANN ZETA Function Converging SERIES NUMBER Theory CRYPTOGRAPHY Signal Processing
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