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Improved Method of Contention-Based Random Access in LTE System

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Journal of Electronic Science and Technology 2018年第2期16卷 175-183页

作者： han-Song su Min Zhang Gao-Hua Liu School of Electronic and Information Engineering Tianjin UniversityTianjin 300072

Random access is the necessary process to establish the wireless link between the user equipment （UE） and network. The performance of the random access directly affects the performance of the network. In this work, we propose a method on the basis of the existing alternatives. In this method, we estimate the system load in advance to adjust the number of terminals. An access threshold is set to control the number of terminals which want to access the base station at an acceptable level. At the same time, we havean improvement on the existing power climbing strategy. We suppose that the power ramping is not always necessary for the re-access. And the selection ofpower ramping steps is studied in this paper. Simulations based on MATLAB are employed to evaluate the effectiveness of the proposed solution and to make comparisons with existing alternatives.

关键词： Access threshold long-term evolution(LTE) power ramping steps random access

Comparative Studies on Mass Spectrometric Fragmentation of Linear Chiral Secondary Alcohols (R)-1-(4-Alkylphenyl) and (R)-1-(4-Alkoxyphenyl/Alkylthiophenyl) Alcohols

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Chemical Research in Chinese Universities 2006年第3期22卷 347-350页

作者： ZhanG Qi-han su Xian-bin XU Jia-xi Key Laboratory of Bioorganic Chemistry and Molecular Engineering College of Chemistry and Molecular Engineering Peking University Beijing 100871 P.R. China

Mass spectrometric behaviour of （R） -1- （ 4-alkylphenyl ） alcohols, 1- （4-alkoxylphenyl） alcohols, and 1- （4-alkylthiophenyl） alcohols were studied with the aid of mass-analyzed ion kinetic energy spectrometry under electron impact ionization. All the title compounds show a tendency to eliminate a water molecule to form alkene ions and undergo an a-cleavago to produce protonated aldehyde ions by the loss of alkyl radicals. Except these two common fragment ions, they also show some different fragmentations due to with or without oxy/thioether-linkage.

关键词： 1-(4-Alkylphenyl) alcohol 1-(4-Alkoxylphenyl) alcohol 1-(4-Alkylthiophenyl) alcohol Electron impact ionization Fragmentation mechanism Mass spectrometry

Electrochemical characteristics of stainless steel using impressed current cathodic protection in seawater

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中国有色金属学会会刊：英文版 2009年第4期19卷 930-934页

作者： Seok-Ki JANG Min-su han Seong-Jong KIM Division of Marine Engineering Mokpo Maritime University

Stainless steels such as STS 304,316 and 630 are frequently used as shaft materials in small fiber reinforced polymer(FRP) fishing *** the shaft material is exposed to a severely corrosive environment such as seawater,it should be protected using appropriate *** impressed current cathodic protection was used to inhibit corrosion in shaft *** anodic polarization,passivity was remarkably more evident in STS 316 stainless steel than in STS 304 and STS *** pitting potentials of STS 304,316,and 630 stainless steels were 0.30,0.323,and 0.260 V,*** concentration polarization due to oxygen reduction and activation polarization due to hydrogen generation were evident in the cathodic polarization trends of all three stainless *** 316 had the lowest current densities in all potential ranges,and STS 630 had the *** analysis showed that STS 316 was the most noble in the *** addition,the corrosion current density was the lowest for STS 316.

关键词：外加电流阴极保护 316不锈钢电化学特性海水腐蚀电流密度材料腐蚀阳极极化 STS

Cross Modal Adaptive Few-Shot Learning Based on Task Dependence

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Chinese Journal of Electronics 2023年第1期32卷 85-96页

作者： DAI Leichao FENG Lin ShanG Xinglin su han School of Computer Science Sichuan Normal University

Few-shot learning(FSL) is a new machine learning method that applies the prior knowledge from some different domains tasks. The existing FSL models of metric-based learning have some drawbacks,such as the extracted features cannot reflect the true data distribution and the generalization ability is weak. In order to solve the problem in the present, we developed a model named cross modal adaptive few-shot learning based on task dependence(COOPERATE for short). A feature extraction and task representation method based on task condition network and auxiliary co-training is proposed. Semantic representation is added to each task by combining both visual and textual features. The measurement scale is adjusted to change the property of parameter update of the algorithm. The experimental results show that the COOPERATE has the better performance comparing with all approaches of the monomode and modal alignment FSL.

关键词： Measurement Adaptation models Visualization Semantics Machine learning Feature extraction Data models

Corrosion and optimum corrosion protection potential of friction stir welded 5083-O Al alloy for leisure ship

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中国有色金属学会会刊：英文版 2009年第4期19卷 898-903页

作者： sung-Hyeon PARK Jong-Shin KIM Min-su han Seong-Jong KIM Division of Maritime Transportation System Mokpo Maritime University Korea Register of Shipping Division of Marine Engineering Mokpo Maritime University

Electrochemical tests were undertaken to determine the optimum conditions in seawater for corrosion protection of friction stir-welded 5083-O Al *** trend observations show that the limiting potential that avoids the effects of hydrogen embrittlement is -1.6 V,corresponding to the crossover point between concentration polarization and activation ***,the optimum protection potential is between -1.5 and -0.7 V since the current density at these values is low in the potentiostatic *** a galvanic cell is formed in the seawater,the welds exhibit electrochemically stable *** parts in galvanic tests with various area ratios are stable and have excellent anticorrosion characteristics.

关键词：搅拌摩擦焊接保护电位海水腐蚀铝合金氧铝船舶休闲防腐

Improvement of hydrogen embrittlement and stress corrosion cracking by annealing for Al-4.4Mg-0.6Mn alloy

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 17-22页

作者： Seong-Jong KIM Min-su han Seong-Kweon KIM Seok-Ki JANG Division of Marine Engineering Mokpo National Maritime University Media Engineering Seoul National University of Technology

With no annealing treatment, cathodic polarization trends in 5083F A1 alloy revealed concentration polarization and activation polarization. However, the annealed specimens have lower current densities at corrosion protection potential compared to the non-annealed specimen. The results of SSRTs conducted in seawater at the applied potential range of-l.8 V to -0.5 V indicated that the maximum tensile strength, elongation, and time-to-fracture had high values at applied potentials of -0.7 to -1.4 V. The maximum tensile strength, elongation, and time-to-f？acture decreased when the potential values were beyond this range in either anodic or cathodic direction. In general, the increased shear lip caused by annealing treatment indicates elongation. Time-to-fracture would likely increase with elongation. Potentials between -0.5 V to -0.6 V were found to be in the region of stress corrosion cracking. The corrosion protection zone was determined to be -0.7 V to -J,4 V because these potential ranges produced good mechanical properties. Potential less than -1.4 V produced a fractured surface with a mixture of dimples （ductile fractures） and a quasi-cleavage pattern resulting from the effects of hydrogen gas.

关键词： annealing 5083F A1-Mg alloy corrosion seawater slow strain rate tests

Advanced forecasting of career choices for college students based on campus big data

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Frontiers of Computer Science 2018年第3期12卷 494-503页

作者： Min NIE Lei YANG Jun suN han su Hu XIA Defu LIAN Kai YAN Big Data Research Center University of Electronic Science and Technology of China Chengdu 611731 China Information Center University of Electronic Science and Technology of China Chengdu 611731 China

Career indecision is a difficult obstacle confronting adolescents. Traditional vocational assessment research measures it by means of questionnaires and diagnoses the potential sources of career indecision. Based on the diagnostic outcomes, career counselors develop treatment plans tailored to students. However, because of personal motives and the architecture of the mind, it may be difficult for students to know themselves, and the outcome of questionnaires may not fully reflect their inner states and statuses. Selfperception theory suggests that students＇ behavior could be used as a clue for inference. Thus, we proposed a data-driven framework for forecasting student career choice upon graduation based on their behavior in and around the campus, thereby playing an important role in supporting career counseling and career guidance. By evaluating on 10M behavior data of over four thousand students, we show the potential of this framework for this functionality.

关键词： campus big data career identity career choiceprediction self-knowledge

Analysis of Cu,Co,V and Zn in Coastal Waters of the East China Sea by Inductively Coupled Plasma Mass Spectrometry(ICP-MS)

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Journal of Ocean University of China 2016年第5期15卷 825-834页

作者： YANG Rujun NING Yutong ZhanG Aibin LI Yan su han College of Chemistry and Chemical Engineering Ocean University of China College of Marine Geoscience Ocean University of China

In this study, a simple method for the simultaneous determination of trace metals(Cu, V, Co, Zn) in coastal seawater using the Mg(OH)2 coprecipitation inductively coupled plasma mass spectrometry(ICP-MS) was developed. This multi-element method enables the simultaneous extraction of four metals, particularly Co and V. The recoveries of Cu, Co, V and Zn after Mg(OH)2 coprecipitation were 73%, 96%, 94% and 92%, which means that our procedure was well-suited to the determination of these four trace metals. The detection limits were 3.81, 0.18, 6.09 and 1.91 nmol L-1, respectively. Then, applying this method to the simultaneous determination of these four metals in coastal water samples from the East China Sea revealed that the concentrations of Cu, Zn, Co and V were higher in bottom waters compared to water at other depths, and higher concentrations were generally observed at the Yangtze River estuary. Additionally, example vertical profiles of dissolved trace metal concentrations for the East China Sea in spring and autumn are compared. These findings indicate that Zn had the greatest seasonal variation followed by Cu, V and Co. For Zn and Co, the concentrations were higher during spring than during autumn. For Cu and V, the seasonal variation in the concentrations was opposite.

关键词： simultaneous dissolved inductively seasonal autumn seawater greatest ammonium waters hydroxide

Electrochemical characteristics of HVOF spray coated layer with WC-27NiCr and WC-10Co4Cr for Al bronze

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中国有色金属学会会刊：英文版 2012年第S3期22卷 753-759页

作者： Min-su han Seung-jun LEE Min-sung KIM Seok-ki JANG Seong-jong KIM Division of Marine Engineering Mokpo Maritime University

Among the environmentally friendly marine energies,tidal current power plants require low cost because they do not need to construct a large *** power is particularly reliable energy source because the power generation capacity is predictable regardless of weather or *** materials or stainless steel have been used as materials of blades for current power ***,their strength and welding performance generated many problems in field *** alloys with excellent cavitation resistance and corrosion resistance were applied as blade materials to improve the durability of copper *** were coated with WC-27NiCr and WC-10Co4Cr using the high velocity oxy-fuel (HVOF) *** metal spray coating technology has the advantage in terms of the selection of materials for cost effectiveness and environmental effects of corrosion because the properties of the coat layer can be controlled *** with WC-27NiCr and WC-10Co4Cr by HVOF,WC-27NiCr shows better corrosion resistance *** reason for this seems to be that corrosion resistance improves and a stable passive film forms due to the effects of Ni and Cr.

关键词： tidal power copper alloys HVOF coating corrosion resistance