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Journal of Central South University 2014年第9期21卷 3513-3517页

作者： Kee-Young kwon College of Engineering Kongju National University

The effect of channel-width chirping on near- and far-field intensity patterns of the six supermodes was investigated. The supermode discrimination was evaluated in various channel-chirped index guided laser arrays. The results show that the linearly channel-chirped laser array has very good supermode discrimination which is better than that of a uniform laser array, the V channel-chirped laser array has the smallest radiation angle of the fundamental supermode among the calculated arrays, and the asymmetrically V channel-chirped array has a very small radiation angle of the fundamental supermode, which is smaller than that of the uniform array and also allows for very good fundamental supermode discrimination against the higher-order supermodes, which is better than that of the V channel-chirped laser array.

关键词： laser array channel-width chirping field pattern modal gain

Chemodynamics of heavy metals in long-term contaminated soils:Metal speciation in soil solution

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Journal of Environmental Sciences 2009年第11期21卷 1532-1540页

作者： kwon-Rae Kim Gary Owens Centre for Environmental Risk Assessment and Remediation University of South Australia Climate Change & Agroecology Division Department of Agricultural Environment National Academy of Agricultural Science

The concentration and speciation of heavy metals in soil solution isolated from long-term contaminated soils were investigated. The soil solution was extracted at 70% maximum water holding capacity （MWHC） after equilibration for 24 h. The free metal concentrations （Cd^2＋, Cu^2＋, Pb^2＋, and Zn^2＋） in soil solution were determined using the Donnan membrane technique （DMT）. Initially the DMT was validated using artificial solutions where the percentage of free metal ions were significantly correlated with the percentages predicted using MINTEQA2. However, there was a significant difference between the absolute free ion concentrations predicted by MINTEQA2 and the values determined by the DMT. This was due to the significant metal adsorption onto the cation exchange membrane used in the DMT with 20%, 28%, 44%, and 8% mass loss of the initial total concentration of Cd, Cu, Pb, and Zn in solution, respectively. This could result in a significant error in the determination of free metal ions when using DMT if no allowance for membrane cation adsorption was made. Relative to the total soluble metal concentrations the amounts of free Cd^2＋（3%-52%） and Zn^2＋（11%-72%） in soil solutions were generally higher than those of Cu^2＋（0.2%-30%） and Pb^2＋（0.6%-10%）. Among the key soil solution properties, dissolved heavy metal concentrations were the most significant factor governing free metal ion concentrations. Soil solution pH showed only a weak relationship with free metal ion partitioning coefficients （Kp） and dissolved organic carbon did not show any significant influence on Kp.

关键词： Donnan membrane technique free metal ion heavy metals partitioning coefficient solubility speciation

Prospect of developing Nd-Fe-B-type magnet with high electrical resistivity

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Rare Metals 2020年第1期39卷 2-12页

作者： Hae-Woong kwon Min-Seok Kang Department of Materials Science and Engineering Pukyong National UniversityBusan48547Republic of Korea

Nd-Fe-B-type magnet is exclusively used as a rotor magnet in the traction motor of hybrid electric vehicle(HEV)and electric vehicle(EV),but its overly high operating temperature is a lingering problem attached to the *** major cause of the high operating temperature is eddy current,which is readily generated in the highly conductive metallic magnet under alternating magnetic field from stator *** this article,temperature rise in the Nd-Fe-B-type magnet with varying electrical resistivity under alternating magnetic field is discussed with the intention of highlighting the importance of enhancing the electrical resistivity for reducing the operating temperature of the Nd-Fe-B-type rotor *** rise in the Nd-Fe-B-type magnet(dielectric salt-added die-upset magnet)with high electrical resistivity is noticeably lower compared to the magnet(commercial sintered rotor magnet)with lower electrical resistivity,substantiating the theory that enhancing the electrical resistivity in the rotor magnet is fairly effective for suppressing the over-rise of its operating temperature during ***-upset process is revealed to be particularly pertinent for the fabrication of highly dense salt-added magnet with high electrical resistivity.

关键词： Rare-earth magnet Nd-Fe-B-type magnet Rotor magnet Operating temperature Eddy current Electrical resistivity

All-hydrocarbon,all-conjugated cycloparaphenylene-polycyclic aromatic hydrocarbon host–guest complexes stabilized by CH–πinteractions

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Nano Research 2022年第6期15卷 5545-5555页

作者： Hyejin kwon Carson.J.Bruns Paul M.Rady Department of Mechanical Engineering University of ColoradoBoulder427 UCB1111 Engineering DriveBoulderCO 80309USA ATLAS Institute 112518th St.320 UCBBoulderCO 80309USA

Polycyclic aromatic hydrocarbons(PAHs)are promising nanocarbon materials with diverse optoelectronic properties,yet they also pose concerning environmental and health *** the ubiquity of PAHs in the environment(crude oil,emissions,and biomass),most supermolecules rely on heteroatoms for *** discovered and characterized a family of all-hydrocarbon,all-π-conjugated[n]cycloparaphenylene-PAH host–guest *** built a theoretical framework to rapidly select these complexes and predict their stabilities,driven exclusively by CH–π*** than a dozen complexes were confirmed experimentally and assembled directly from commercially available *** motif offers a versatile way to combine the advantageous properties of organic semiconductors with the rich dynamic,stereochemical,stimulus-responsive,and stressdissipative behavior of host–guest complexes,while creating new opportunities for bespoke PAH separation or remediation materials.

关键词： cycloparaphenylenes density functional calculations host−guest systems hydrocarbons polycycles self-assembly supramolecular chemistry

Blockchain Consistency Check Protocol for Improved Reliability

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Computer Systems Science & Engineering 2021年第2期36卷 281-292页

作者： Mohammed Alwabel Youngmi kwon Department of Radio and Information Communications Engineering Chungnam National UniversityDaejeonKorea

Blockchain is a technology that provides security features that can be used for more than just *** achieves security by saving the information of one block in the next *** the information of one block will require changes to all the next block in order for that change to take *** makes it unfeasible for such an attack to ***,the structure of how blockchain works makes the last block always vulnerable for attacks,given that its information is not saved yet in any *** allows malicious node to change the information of the last block and generate a new block and broadcast it to the *** that the nodes always follow the longer chain wins rule,the malicious node will win given that it has the longest chain in the *** paper suggests a solution to this issue by making the nodes send consistency check messages before broadcasting a *** the nodes manage to successfully verify that the node that generated a new block hasn’t tampered with the blockchain than that block will be *** results of the simulation show suggested protocol provided better security compared to the regular blockchain.

关键词： Blockchain security forking blockchain consistency check(BCC) protocol

Adaptive Consistent Management to Prevent System Collapse on Shared Object Manipulation in Mixed Reality

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Computers, Materials & Continua 2023年第4期75卷 2025-2042页

作者： Jun Lee Hyun kwon Department of Game Software Hoseo UniversityAsan-siKorea Department of Artificial Intelligence and Data Science Korea Military AcademySeoulKorea

A concurrency control mechanism for collaborative work is akey element in a mixed reality environment. However, conventional lockingmechanisms restrict potential tasks or the support of non-owners, thusincreasing the working time because of waiting to avoid conflicts. Herein, wepropose an adaptive concurrency control approach that can reduce conflictsand work time. We classify shared object manipulation in mixed reality intodetailed goals and tasks. Then, we model the relationships among goal,task, and ownership. As the collaborative work progresses, the proposedsystem adapts the different concurrency control mechanisms of shared objectmanipulation according to the modeling of goal–task–ownership. With theproposed concurrency control scheme, users can hold shared objects andmove and rotate together in a mixed reality environment similar to realindustrial sites. Additionally, this system provides MS Hololens and Myosensors to recognize inputs from a user and provides results in a mixed realityenvironment. The proposed method is applied to install an air conditioneras a case study. Experimental results and user studies show that, comparedwith the conventional approach, the proposed method reduced the number ofconflicts, waiting time, and total working time.

关键词： Mixed reality upper body motion recognition shared object manipulation adaptive task concurrency control

New Spam Filtering Method with Hadoop Tuning-Based MapReduce Naïve Bayes

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Computer Systems Science & Engineering 2023年第4期45卷 201-214页

作者： Keungyeup Ji Youngmi kwon Department of Radio and Information Communications Engineering Chungnam National UniversityDaejeon34134Korea

As the importance of email increases,the amount of malicious email is also increasing,so the need for malicious email filtering is *** it is more economical to combine commodity hardware consisting of a medium server or PC with a virtual environment to use as a single server resource and filter malicious email using machine learning techniques,we used a Hadoop MapReduce framework and Naïve Bayes among machine learning methods for malicious email ***ïve Bayes was selected because it is one of the top machine learning methods(Support Vector Machine(SVM),Naïve Bayes,K-Nearest Neighbor(KNN),and Decision Tree)in terms of execution time and *** email was filtered with MapReduce programming using the Naïve Bayes technique,which is a supervised machine learning method,in a Hadoop framework with optimized performance and also with the Python program technique with the Naïve Bayes technique applied in a bare metal server environment with the Hadoop environment not *** to the results of a comparison of the accuracy and predictive error rates of the two methods,the Hadoop MapReduce Naïve Bayes method improved the accuracy of spam and ham email identification 1.11 times and the prediction error rate 14.13 times compared to the non-Hadoop Python Naïve Bayes method.

关键词： Hadoop hadoop distributed file system(HDFS) MapReduce configuration parameter malicious email filtering Naïve Bayes

Novel Rifle Number Recognition Based on Improved YOLO in Military Environment

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Computers, Materials & Continua 2024年第1期78卷 249-263页

作者： Hyun kwon Sanghyun Lee Department of Artificial Intelligence and Data Science Korea Military AcademySeoulKorea Graduate School of Information Security Korea Advanced Institute of Science and TechnologyDaejeonKorea

Deep neural networks perform well in image recognition,object recognition,pattern analysis,and speech *** military applications,deep neural networks can detect equipment and recognize *** military equipment,it is necessary to detect and recognize rifle management,which is an important piece of equipment,using deep neural *** have been no previous studies on the detection of real rifle numbers using real rifle image *** this study,we propose a method for detecting and recognizing rifle numbers when rifle image data are *** proposed method was designed to improve the recognition rate of a specific dataset using data fusion and transfer *** the proposed method,real rifle images and existing digit images are fusedas trainingdata,andthe final layer is transferredto theYolov5 *** detectionand recognition performance of rifle numbers was improved and analyzed using rifle image and numerical *** used actual rifle image data(K-2 rifle)and numeric image datasets,as an experimental *** was used as the machine learning *** results show that the proposed method maintains 84.42% accuracy,73.54% precision,81.81% recall,and 77.46% F1-score in detecting and recognizing rifle *** proposed method is effective in detecting rifle numbers.

关键词： Machine learning deep neural network rifle number recognition detection

The two faces of IL-2: a key driver of CD8^(+)T-cell exhaustion

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Cellular & Molecular Immunology 2021年第7期18卷 1641-1643页

作者： Byungsuk kwon School of Biological Sciences University of UlsanUlsanRepublic of Korea

The body undergoes abnormal,pathological immune responses when antigens are present at too great an excess for the immune system to handle or the body is persistently exposed to *** etiology of many types of chronic diseases is partially related to such conditions;thus,understanding the pathophysiological processes of these chronic diseases is of paramount importance for therapeutic purposes.A recent paper published in Nature Immunology revealed the unexpected involvement of the T cell-activating cytokine interleukin(IL)-2 in counteracting the immune attack on tumors,a finding that will provide new options for cancer therapy.

关键词： involvement diseases Immunology

Development of mathematically motivated hybrid soft computing models for improved predictions of ultimate bearing capacity of shallow foundations

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第3期15卷 747-759页

作者： Abiodun Ismail Lawal Sangki kwon Department of Energy Resources Engineering Inha UniversityIncheonSouth Korea Department of Mining Engineering Federal University of TechnologyAkureNigeria

Ultimate bearing capacity(UBC)is a key subject in geotechnical/foundation engineering as it determines the limit of loads imposed on the *** most reliable means of determining UBC is through experiment,but it is costly and time-consuming which has led to the development of various models based on the simplified *** outcomes of the models are usually validated with the experimental results,but a large gap usually exists between ***,a model that can give a close prediction of the experimental results is *** study proposes a grasshopper optimization algorithm(GOA)and salp swarm algorithm(SSA)to optimize artificial neural networks(ANNs)using the existing UBC experimental *** performances of the proposed models are evaluated using various statistical *** obtained results are compared with the existing *** proposed models outperformed the existing *** proposed hybrid GOA-ANN and SSA-ANN models are then transformed into mathematical forms that can be incorporated into geotechnical/foundation engineering design codes for accurate UBC measurements.

关键词： Ultimate bearing capacity(UBC) Geotechnics Grasshopper optimization algorithm(GOA) Salp swarm algorithm(SSA) Soft computing(SC)method