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中华高血压杂志 2012年第6期20卷 599-599页

作者： flythe je Kunaparaju S Dinesh K Cape K Feldman HI Brunelli SM 刘莉叶鹏

血液透析时血压的不稳定性虽早有认识，但对造成透析时非系统性血压变异性的因素知之甚少。方法：进行前瞻性观察队列研究。研究对象是来自5个透析中心接受普通透析的随机患者218例。

关键词：血液透析收缩压变异性血压变异性不稳定性队列研究普通透析透析中心

APPLICATION OF WAVELET TRANSFORM ON DIAGNOSIS AND PREDICTION OF MILLING CHATTER

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Chinese Journal of Mechanical Engineering 2007年第3期20卷 67-70页

作者： LUO Ming-je Department of Mechanical Engineering R&D Center for Membrane Technology Chung Yuan Christian University Chung-Li 32023 Taiwan China

In order to avoid the accuracy deterioration or tool damage caused by milling chatter, it is necessary to have an efficient and reliable diagnosis system that can on-line predict/detect the occur-rence of chatter. The diagnosis/predicting system proposed is to on-line process and analysis the vi-bration signals of the milling machine measured by accelerometers. According to the analysis results, the system will be able to detect/predict the occurrence of the chatter. The diagnosis algorithm is, first, collecting both the normal signals and chatter signals from milling processes, and then, converting the signals through wavelet transform and fast Fourier transform （FFT）. Since the converted chatter sig-nals exhibit different characteristics from the normal signals, through defining the characteristic val-ues, such as root-mean-square value, max value, and ratio of peak value to root-mean-square value, etc, a diagnosis reference library that contains the distribution of these characteristic values is built for diagnosis. When a diagnosis is executing, the characteristic value of the measured signals is con-trasted with the diagnosis reference. The approach index which shows the possibility of occurrence of milling chatter will, then, be calculated through the diagnosis system. Cutting experiments are con-ducted to verify the proposed diagnosis system. The results show the success of early chatter detecting for the system.

关键词： Chatter On-line diagnosis Prediction Wavelet transform

Applying machine learning techniques to predict detonation initiation fromhot spots

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Energy and AI 2022年第3期9卷 121-127页

作者： je Ir Ryu Department of Mechanical Engineering University of California-BerkeleyBerkeleyCA 94720USA

As hot spots can be a source of detonation initiation by autoignition in a reactive mixture, understanding hotspot initiated detonation is significantly important for energy-related applications of detonation. Although theZel’dovich reactivity gradient theory is extremely useful to predict reaction propagation modes from hot spots,the prediction is limited due to the changes in the unburnt mixture during the induction time. In the currentstudy, machine learning based estimation methods by training the numerical simulation result data set aresuggested to avoid the extensive and empirical effort to find initial conditions of hot spot initiated detonationin inhomogeneous mixtures. The data set was obtained from the detailed numerical simulations with variousconditions of hot spots and divided into training and test data sets. Some variables were normalized withothers to avoid multicollinearity. Three different machine learning techniques, logistic regression, classificationand regression trees, and artificial neural network, were utilized to develop prediction models. Using thedeveloped models by machine learning approaches, the modes of hot spot initiated reaction front propagationcan be predicted without computationally expensive numerical simulations. The accuracies of the machinelearning based prediction models were significantly improved compared to the baseline model simply usingthe Zel’dovich reactivity gradient theory. These models can be utilized as preliminary prediction methods ofhot spot induced detonation initiation conditions for further detailed numerical simulations and dominantinput variables.

关键词： Detonation Deflagration Hydrogen Syngas Logistic regression CART Artificial neural network

Valorization of Tree Bark-Derived Suberin in Applications for the Bio-Based Composites Industry–A Recent Review

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Journal of Renewable Materials 2024年第6期12卷 1029-1042页

作者： Aleksandra jeżo Institute of Wood Sciences and Furniture SGGWNowoursynowska St.159Warsaw02-776Poland

Bark extracts are sustainable sources of biopolymers and hold great promise for replacing fossil fuel-based polymers,for example,in wood-based *** addition to primary and secondary metabolites,tree bark also contains suberin,which plays a major role in protecting the tree from environmental *** is a natural aliphatic-aromatic cross-linked polyester present in the cell walls of both normal and damaged external tissues,the main component of which are long-chain aliphatic *** main role as a plant ingredient is to protect against microbiological factors and water *** of the most important suberin monomers are suberin fatty acids,known for their hydrophobic and barrier ***,due to the diverse chemical composition of suberin,it is an attractive alternative to hydrocarbon-based *** its potential is recognized,it is not widely used in biocomposites technology,including wood-based composites and the polymer *** article will discuss the current knowledge about the potential of suberin and its components in biocomposites technology,which will include surface finishes,composite adhesives and polymer blends.

关键词： Suberin suberinic acids wood composites biocomposites biopolyester

Microstructure characteristics and effect of grain orientation on magnetic properties of Fe_(63)Co_(32)Gd_5 alloy ribbons

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Journal of Central South University 2015年第6期22卷 2014-2019页

作者：姚文静王楠 LEE je-hyun Key Laboratory of Space Applied Physics and Chemistry of Ministry of Education School of Science Northwestern Polytechnical University Engineering Research Center for Integrated Mechatronics Materials and Components Changwon National University

By using the melt spinning techniques, the Fe63Co32Gd5 alloy ribbons with 15-50 m in thickness and 3-7 mm in width were prepared at the wheel speeds of 15, 20, 25 and 35 m/s. The rapid solidification microstructures were characterized by three layers, the middle layer of which reaches 80% thickness and forms the column grain of(Fe,Co) solid with Gd solution. Grain refinement takes place with the increase of the wheel speed. And after 0.5 h heat treatment at 823 K, the ribbon thickness becomes larger and the middle layer of column grain is very orderly perpendicular to the ribbon plane. The coercivity of quenched and annealed Fe63Co32Gd5 ribbons both have the inflection point at the wheel speed of 20 m/s, and the tendency is declining. The heat treatment processing makes the coercivity become lower by improving the order of(Fe,Co)17Gd2 compound. The saturation magnetization of quenched ribbons increases with the enhancement of wheel speed, whereas that of annealed ones decreases firstly and then increases. The minimum coercivity is 5.30×103 A/m and the maximum saturation magnetization is 163.62 A·m2/kg, which is obtained in the conditions of the wheel speed of 35 m/s and 0.5 h heat treatment at the temperature of 823 K.

关键词： Fe-Co-Gd alloy ribbon rapid solidification phase composition magnetic properties

Photophysical,optical,and photocatalytic hydrogen production properties of layered-type BaNb_(2-x)Ta_(x)P_(2)O_(11)(x=0,0.5,1.0,1.5,and 2.0)compounds

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Journal of Materials Science & Technology 2022年第3期98卷 26-32页

作者： Min je Kang Gill Sang Han In Sun Cho Department of Materials Science and Engineering Ajou UniversitySuwon 16499Republic of Korea Department of Energy Systems Research Ajou UniversitySuwon 16499Republic of Korea School of Advanced Materials Science and Engineering Sungkyunkwan UniversitySuwon 16419Republic of Korea

Layered-type metal phosphates of BaNb_(2-x)Ta_(x)P_(2)O_(11)(x=0,0.5,1.0,1.5,and 2.0)were synthesized using a solid-state reaction *** photophysical,optical,and photocatalytic hydrogen production properties of the resulting powders were investigated for the first ***-pure and homogeneous powders with irregular morphologies were obtained at a calcination temperature of 1200℃.As the Ta content increased,the interlayer distance along the c-axis increased by up to 0.14%.Additionally,the optical bandgap values increased from 3.32 to 3.59 *** energy band positions were estimated from the Mott–Schottky ***_(2)P_(2)O_(11)(x=0)exhibited the lowest conduction band edge position(-0.14 V *** normal hydrogen electrode,NHE),which is located above the water reduction potential(0.0 V ***).In comparison,BaTa_(2)P_(2)O_(11)(x=2.0)exhibited the highest conduction band edge position(-0.29 V ***),comparable to that of TiO_(2).The photocatalytic activity for hydrogen produced from splitting water was measured under ultraviolet light ***,BaTa_(2)P_(2)O_(11)exhibited the highest activity(7.3μmol/h),which was 15 and 10 times larger than BaNb_(2)P_(2)O_(11)(0.5μmol/h)and nano-TiO_(2)(0.7μmol/h),*** activity of BaTa_(2)P_(2)O_(11)increased to 24.4μmol/h after deposition of the NiO_(x)co-catalyst(1 wt.%),which remained stable during continuous operation(~35 h).

关键词： BaNb_(2)P_(2)O_(11) BaTa_(2)P_(2)O_(11) Layered crystal structure Bandgap Band edge positions Photocatalytic hydrogen production

A post-processing method for true random number generators based on hyperchaos with applications in audio-based generators

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Frontiers of Computer Science 2020年第6期14卷 85-95页

作者： je Sen TEH Weijian TENG Azman SAMSUDIN Jiageng CHEN School of Computer Sciences Universiti Sains MalaysiaPenang 11800Malaysia School of Engineering and Technology INTI International College PenangPenang 11900Malaysia School of Computer Central China Normal UniversityWuhan 430079China

True random number generators(TRNG)are important counterparts to pseudorandom number generators(PRNG).especially for high security applications such as *** produce unpredictable,non-repeatablerandom ***,most TRNGs require specialized hardware to extract entropy from physical phenomena and tend to be slower than *** generators usually require post-processing algorithms to eliminate biases but in *** *** this paper.a newpost-processing method based on hyperchaos is proposed forsoftware-based TRNGs which not only eliminates statisticalbiases but also provides amplification in order to improve the performance of *** proposed method utilizes the inherent characteristics of chaos such as hypersensitivity to input shanugeri,diffusisn,and csnfusion sapabilities to ushievethese *** bits of a physical entropy source areused to perturb the parameters of a hyperchaotic map,which is then iterated to produce a set of random output *** de-pict the feasibility of the proposed post-processing *** is applied in designing TRNGs based on digital *** are analyzed to identify statistical defects in addition to forward and backward *** indicate that the proposed generators are able to produce secure true random sequences at a high throughput,which in turn reflects on the effectiveness of the proposed post-processing method.

关键词： audio chaos theory chaotic map entropy hyperchaos post-processing random number generator security

Additive manufacturing of flexible 3D surface electrodes for electrostatic adhesion control and smart robotic gripping

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Friction 2023年第11期11卷 1974-1986页

作者： Dong Geun KIM Hyeongmin je AJohn HART Sanha KIM Department of Mechanical Engineering Korea Advanced Institute of Science and TechnologyDaejeon 34141Republic of Korea Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA

Mechanically flexible surface structures with embedded conductive electrodes are attractive in contact-based devices,such as those used in reversible dry/adhesion and tactile *** shapes of the surface structures strongly determine the contact behavior and therefore the resulting adhesion and sensing functionalities;however,available features are often restricted by fabrication ***,we additively manufacture elastomeric structure arrays with diverse angles,shapes,and sizes;this is followed by integration of conductive nanowire *** fabricated flexible three-dimensional(3D)surface electrodes are mechanically compliant and electrically conductive,providing multifunctional ability to sense touch and to switch adhesion via a combined effect of shear-and electro *** designed soft,anisotropic flexible structures to mimic the gecko’s reversible adhesion,which is governed by van der Waals forces;we integrated nanowires to further manipulate the localized electric field among the adjacent flexible 3D surface electrodes to provide additional means to digitally tune the electrostatic attraction at the contact *** addition,the composite surface can sense the contact force via capacitive *** our flexible 3D surface electrodes,we demonstrate a complete soft gripper that can grasp diverse convex objects,including metal,ceramic,and plastic products,as well as fresh fruits,and that exhibits 72%greater electroadhesive gripping force when voltage is applied.

关键词： electroadhesion tactile sensing robotic gripper additive manufacturing dry adhesive

Influence of Experimental Parameters on Reactive Magnetron Sputtering CN_x Thin Films

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Journal of Materials Science & Technology 1997年第2期13卷 154-156页

作者： Zheng, WT Ding, T Ivanov, I Sundgren, je JILIN UNIV DEPT MAT SCICHANGCHUN 130023PEOPLES R CHINA LINKOPING UNIV DEPT PHYSS-58183 LINKOPINGSWEDEN

Carbon nitride thin films were deposited on Si(001) using unbalanced magnetron sputtering at different experimental parameters. The effects of nitrogen partial pressure, substrate temperature and substrate bias on the... 详细信息

关键词： Carbon

A taxonomic review of the genus Miaenia Pascoe, 1864(Coleoptera: Cerambycidae) from South Korea with a new record of M. tonsa(Bates)

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Journal of Forestry Research 2018年第3期29卷 822-829页

作者： Ik je Choi Tae Sung Kwon Jongok Lim Silkworm and Insect Management Center Gyeongsangbuk-do Agricultural Resource Management Institute Forest Insect Pests and Disease Division Korea Forest Research Institute Division of Forest Biodiversity Korea National Arboretum

The cerambycid genus Miaenia Pascoe(Coleoptera: Cerambycoidea) of South Korea is taxonomically reviewed. Two species, Miaenia fasciata fasciata(Matsushita) and Miaenia maritima Tsherepanov have been recorded. In this paper, M. tonsa(Bates) is added to the Korean cerambycid fauna for the first time. A key to Korean Miaenia species, re-description and diagnostic illustrations, including male genitalia for each species, are provided.

关键词： Acanthocinini Cerambycidae Miaenia New species South Korea Taxonomy