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Zonal distribution and population biology of Ilyoplax frater (Brachyura:Ocypodoidea:dotillidae) in a coastal mudflat of Pakistan

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Current Zoology 2010年第2期56卷 244-251页

作者： Noor us SAHER Naureen Aziz QURESHI Centre of Excellence in Marine Biology University of Karachi Department of Fisheries and Aquaculture University of Veterinary and Animal Sciences

Zonal distribution and population biology of llyoplaxfrater were studied in a mangrove mudflat area of Pakistan. The crabs were collected from Korangi creek through transect and quadrat method from low tide level to high tide level. Two transects were delimited in a mangrove area of Korangi creek （24°79′N/67°20′E）. On each transect, three 0.25 m quadrats were sampled at three tidal levels on a monthly basis during low tide periods from March 2001 to February 2002. A total of 1124 crabs were obtained, of which 482 were males and 642 were females. Density of crabs varied between 0 and 90/m^2. The density and size distribution varied and showed significant differences from low to high tide level, and were positively correlated with the percent moisture, percent organic matter and sediment grain size. The carapace width （CW） ranged from 2.5 to 11.5 mm for male and 2.5 to 11.0 mm for female and was not significantly different. The overall sex ratio did not differ significantly from the expected 1：1 throughout the year in small crabs but was significantly different in adult crabs （Z2 = 49.73） with more male crabs, Size frequency distribution showed recruitment of juvenile crabs （〈 4 mm） nearly throughout the year except during June and July. Presence of ovigerous females in all months with seasonal peaks in September, October, December and May indicates seasonal continuous breeding. Weight of egg mass increases with weight of ovigerous females and show positive linear relationship. The estimated mean diameter of egg was 2.83±0.25μm, and the average number of eggs was 3065±902.

关键词： Ilyoplaxfrater Population biology Zonal distribution Sex ratio Fecundity Korangi creek Pakistan

Temporal variations of mesozooplankton abundance and biomass in the mangrove creek area along the Karachi coast, Pakistan

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Acta Oceanologica Sinica 2014年第12期33卷 222-230页

作者： Farah Naz Naureen Aziz Qureshi Noor us Saher Centre of Excellence in Marine Biology University of Karachi Department of Zoology Government College University

The temporal variations of mesozooplankton abundance and biomass （1-Volumetric method by settling volume and displacement volume and 2- Gravimetric method through wet weight, dry weight and ash-free dry weight） with relation to environmental parameters were studied in the mangrove creek area of Karachi coast, Pakistan. The data of mesozooplankton samples along with environmental parameters （temperature, salinity, pH, etc.） were collected during January 1998 to December 1998 from two creek stations. The abun-dance of mesozooplankton also exhibited seasonal trends at both stations. At Sta. S2, the highest and low-est abundance values were observed during post-monsoon and southwest monsoon respectively whereas, at Sta. S1, a clear trend of high abundance in pre-monsoon to low abundance in southwest monsoon was observed. Mesozooplankton abundance was also positively correlated with settling volume, displacement volume, wet weight and dry weight. The highest biomass value was observed in the northeast monsoon and pre-monsoon periods. The results of the canonical analysis of the output from the discriminate function was tested. Out of fifteen variables, only one was significantly different in single character ratios dry weight/ash free-dry weight （F3,23=4.78,P＆lt;0.005）. The mesozooplankton community was collectively composed of 28 taxa. Among these groups, copepoda （66.3%）, gastropod larvae （9.94%）, evadne （4.60%）, zoea （3.60%）, cypris nauplii （2.56%）, lemellibranch larvae （1.87%）, chaetognaths （1.81%）, ostracods （1.73%）, lucifer （1.15%） and barnacles nauplii （1.35%） contributed the most to the similarities within Sta. S1, while copepoda （74.68%）, cypris nauplii （5.29%）, gastropods （4.87%）, barnacles nauplii （4.81%）, evadne （1.72%）, zoea （1.53%） and ca-ridean larvae （1.18%） at Sta. S2. The remaining mesozooplanktonic group were accounted for less than 5% and 6% at Sta. S1 and Sta. S2 respectively, of the total organisms. Similarity percentage （SIMPER） analysis revealed t

关键词： mesozooplankton abundance biomass Karachi Pakistan

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

Artificial optoelectronic synapse based on spatiotemporal irradiation to source-sharing circuitry of synaptic phototransistors

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InfoMat 2024年第2期6卷 131-141页

作者： Seungho Song Changsoon Choi Jongtae Ahn je-Jun Lee Jisu Jang Byoung-Soo Yu Jung Pyo Hong Yong-Sang Ryu Yong-Hoon Kim do Kyung Hwang Center for Opto-Electronic Materials and Devices Post-Silicon Semiconductor InstituteKorea Institute of Science and Technology(KIST)SeoulRepublic of Korea School of Advanced Materials Science and Engineering Sungkyunkwan UniversitySuwonRepublic of Korea Center for Spintronics Post-Silicon Semiconductor InstituteKorea Institute of Science and Technology(KIST)SeoulRepublic of Korea Division of Nanoscience&Technology KIST SchoolUniversity of Science and Technology(UST)SeoulRepublic of Korea School of Biomedical Engineering Korea UniversitySeoulRepublic of Korea KU-KIST Graduate School of Converging Science and Technology Korea UniversitySeoulRepublic of Korea

To overcome the intrinsic inefficiency of the von Neumann architecture,neuromorphic devices that perform analog vector–matrix multiplication have been highlighted for achieving power-and time-efficient data *** particular,artificial synapses,of which conductance should be programmed to represent the synaptic weights of the artificial neural network,have been intensively researched to realize neuromorphic ***,inspired by excitatory and inhibitory synapses,we develop an artificial optoelectronic synapse that shows both potentiation and depression characteristics triggered only by optical *** design of the artificial optoelectronic synapse,in which excitatory and inhibitory synaptic phototransistors are serially connected,enables these characteristics by spatiotemporally irradiating the phototransistor channels with optical ***,a negative synaptic weight can be realized without the need for electronic components such as *** such attributes,the artificial optoelectronic synapse is demonstrated to classify three digits with a high recognition rate(98.3%)and perform image preprocessing via analog vector-matrix multiplication.

关键词： amorphous oxide semiconductor analog processing artificial synapse neuromorphic optoelectronics

Activity and Stability of Rare Earth-Based Hydride Alloys as Catalysts of Hydrogen Absorption-Oxidation Reactions

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Journal of Rare Earths 2004年第6期22卷 871-874页

作者：应桃开高学平胡伟康 Noréus Dag College of Biology and Chemistry Zhejiang Normal University Jinhua 321004China Institute of New Energy Material Chemistry Nankai University Tianjin 300071China Department of Structural Chemistry Arrhenius Laboratory Stockholm University S-106 91 Stockholm Sweden

Rare earth-based AB(5)-type hydrogen storage alloys as catalysts of hydrogen-diffusion electrodes for hydrogen absorption and oxidation reactions in alkaline fuel cells were investigated. It is demonstrated that the metahydride hydrogen-diffusion electrodes could be charged by hydrogen gas and electrochemically discharged, at the same time to retain a stable oxidation potential for a long period. The catalytic activities and stability are almost comparable with a Pt catalyst on the active carbon. Further improvement of performances is expected via reduction of catalyst size into nanometers.

关键词： inorganic chemistry electrocatalyst alkaline fuel cell hydrogen oxidation rare earths

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

Shine bright: considerations on the use of fluorescent substrates in living monoaminergic neurons in vitro

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Neural Regeneration Research 2015年第9期10卷 1383-1385页

作者： Patrick Schloss Friederike Matth?us Thorsten Lau Biochemical Laboratory Department of Psychiatry and Psychotherapy Central Institute of Mental Health Medical Faculty Mannheim

The biogenic monoamines dopamine （DA）, norepinephrine （NE） and serotonin （5-hydroxytryptamine, 5-HT） are major neuromodulators in the mammalian central nervous system （CNS）. DA containing neurons are found in i） the mesolimbic system in which cell bodies in the ventral tegmental area （VTA） project axons into the amygdala, cortex, hippocampus and the nucleus accumbens; and ii） the nigrostriatal system in which cell bodies located in the substantia nigra pars compacta send their axons into the dorsolateral parts of the striatum （Bjorklund and Dunnett, 2007）. The central noradrenergic neurons are concentrated in distinct brainstem nuclei with the locus coeruleus （LC） being the most prominent nucleus which projects a diffusely arborizing axonal network to most areas of the CNS （Szabadi, 2013）.

关键词： FFN Shine bright considerations on the use of fluorescent substrates in living monoaminergic neurons in vitro

Interferometric orbit determination for geostationary satellites

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Science China(Information Sciences) 2017年第6期60卷 22-32页

作者： Roger M.FusTER Marc FERNNDEZ usóN Antoni BROQUETAS IBARS Remote Sensing Laboratory Department of Signal and Communications TheoryUniversitat Politècnica de Catalunya

Future Geo SAR missions are expected to provide higher resolution radar images featuring shorter revisit times by locating a radar payload on-board of a geostationary satellite. One of the main challenges in Geo SAR processing is accurately determining the satellite orbit to obtain a precise phase history, in order to properly focus the retrieved data. To tackle this challenge, a multiple baseline ground-based interferometer is proposed as a compact and reliable method to achieve an unprecedented accuracy. As a proof of concept, this paper presents the results obtained from a single baseline prototype, whose results can be extrapolated to a larger system, able to be used in future missions.

关键词： GeoSAR interferometry orbit determination geostationary SAR