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ESG Discourse Analysis Through BERTopic: Comparing News Articles and Academic Papers

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Computers, Materials & Continua 2023年第6期75卷 6023-6037页

作者： Haein lee Seon hong lee Kyeo Re lee Jang Hyun Kim Department of Applied Artificial Intelligence/Department of Human-Artificial Intelligence Interaction Sungkyunkwan UniversitySeoul03063Korea Center for SW Education Hanyang UniversityAnsan15588Korea Department of Interaction Science/Department of Human-Artificial Intelligence Interaction Sungkyunkwan UniversitySeoul03063Korea

Environmental,social,and governance(ESG)factors are critical in achieving sustainability in business management and are used as values aiming to enhance corporate ***,non-financial indicators have been considered as important for the actual valuation of corporations,thus analyzing natural language data related to ESG is *** previous studies limited their focus to specific countries or have not used big *** methodologies are insufficient for obtaining potential insights into the best practices to leverage *** address this problem,in this study,the authors used data from two platforms:LexisNexis,a platform that provides media monitoring,and Web of Science,a platform that provides scientific *** big data were analyzed by topic *** modeling can derive hidden semantic structures within the *** this process,it is possible to collect information on public and academic *** authors explored data from a text-mining perspective using bidirectional encoder representations from transformers topic(BERTopic)—a state-of-the-art topic-modeling *** addition,changes in subject patterns over time were considered using dynamic topic *** a result,concepts proposed in an international organization such as the United Nations(UN)have been discussed in academia,and the media have formed a variety of agendas.

关键词： ESG BERTopic natural language processing topic modeling

Video learning based image classification method for object recognition

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journal of Central South University 2013年第9期20卷 2399-2406页

作者： lee hong-ro SHIN Yong-ju Department of NTIS Center Korea Institute of Science & Technology Information

Automatic image classification is the first step toward semantic understanding of an object in the computer vision *** key challenge of problem for accurate object recognition is the ability to extract the robust features from various viewpoint images and rapidly calculate similarity between features in the image database or video *** order to solve these problems,an effective and rapid image classification method was presented for the object recognition based on the video learning *** optical-flow and RANSAC algorithm were used to acquire scene images from each video *** the selection of scene images,the local maximum points on comer of object around local area were found using the Harris comer detection algorithm and the several attributes from local block around each feature point were calculated by using scale invariant feature transform （SIFT） for extracting local ***,the extracted local descriptor was learned to the three-dimensional pyramid match *** results show that our method can extract features in various multi-viewpoint images from query video and calculate a similarity between a query image and images in the database.

关键词： image classification multi-viewpoint image feature extraction video learning

Polyaniline and multi-walled carbon nanotube composite electrode for rechargeable battery

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中国有色金属学会会刊：英文版 2012年第S3期22卷 717-721页

作者： Yu-Jeong LIM Min-Young PARK Sang-Keol lee Won-Ki lee Nam-Ju jo Department of Polymer Science & Engineering Pusan National University Hankook Tire Co.Ltd. Department of Polymer Engineering Pukyong National University

The multi-walled carbon nanotube was introduced into the polymer matrix (PANI) to improve the electric conductivity as well as mechanical properties of the original polymer ***/multi-walled carbon nanotube (MWCNT) composites were synthesized via ex-situ and in-situ polymerization to improve their electrical *** the DC conductivities of PANI/MWCNT according to content and diameter of MWCNT were measured by four-point *** highest electric conductivity of PANI/MWCNT composite is 20 S/cm when 0.3% (mass fraction) MWCNTs with 10 nm in diameter and 15 μm in length are added in composite.

关键词： polymer electrode electric conductivity multi-walled carbon nanotube conducting polymer

Effects of Craddition on Charpy impact energy in austenitic 0.45C-24Mn-(0,3,6)Cr steels

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journal of Materials Science & Technology 2020年第15期47卷 21-30页

作者： Seok Gyu lee Bohee Kim Min Cheol jo Kyeong-Min Kim Junghoon lee Jinho Bae Byeong-joo lee Seok Su Sohn Sunghak lee Center for Advanced Aerospace Materials Pohang University of Science and TechnologyPohang37673South Korea Steel Products Design Team Hyundai SteelDangjin31779South Korea Steel Products Research Group 1 Technical Research LaboratoriesPOSCOGwangyang57807South Korea Department of Materials Science and Engineering Korea UniversitySeoul02841South Korea

Effects of Cr addition(0,3,and 6 wt%) on Charpy impact properties of Fe-C-Mn-Cr-based steels were studied by conducting dynamic compression tests at room and cryogenic *** room temperature,deformation mechanisms of Charpy impacted specimens were observed as twinning induced plasticity(TWIP) without any transfo rmation induced plasticity(TRIP) in all the *** cryogenic temperature,many twins were populated in the Cr-added steels,but,interestingly,fine ε-martensite was found in the OCr steel,satisfying the Shoji-Nishiyama(S-N) orientation relationship,{111}γ//{0002}ε and γ//ε.Even though the cryogenic-temperature staking fault energies(SFEs) of the three steel were situated in the TWIP regime,the martensitic transformation was induced by Mn-and Cr-segregated *** the OCr steel,SFEs of low-(Mn,Cr) bands lay between the TWIP and TRIP regimes which were sensitively affected by a small change of *** dynamic compressive test results well showed the relation between segregation bands and the *** of Cr were known as not only increasing the SFE but also promoting the carbide *** order to identify the possibility of carbide formation,a precipitation kinetics simulation was conducted,and the predicted fractions of precipitated M23C6 were negligible,0.4-1.1×10-5,even at the low cooling rate of 10℃/s.

关键词： Austenitic high-Mn steels Charpy impact energy Split Hopkinson pressure bar Twinning induced plasticity(TWIP) Transformation induced plasticity(TRIP) Stacking fault energy(SFE)

Recent TCP(Tidal Current Power) projects in Korea

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Science China(Technological Sciences) 2010年第1期53卷 57-61页

作者： Chul Hee jo Kang Hee lee Yu Ho RHO School of Engineering Inha University253Yonghyun-DongNam-GuIncheon 402-751Republic of Korea Graduate School Department.of Naval Architecture & Ocean EngineeringInha University253Yonghyun-DongNam-GuIncheon 402-751Republic of Korea

Having strong current on the west coast with up to 10 m tidal range in Korea,there are many suitable and applicable locations for TCP(Tidal Current Power) application in *** only the west coast,but also the south west regions having narrow channels between islands creating fast ocean stream are suitable for *** first TCP application in Korea is 1 MW helical VAT(Vertical Axis Turbine) device installed in Wooldolmog area in *** first HAT(Horizontal Axis Turbine) TCP device of 25 KW was developed and installed in cooling water weir of Samchonpo power plant in ***,a 100 kW prototype HAT TCP device is being planned to be installed in Daebang strait in *** big project would be Inchon TCP farm of 200 MW on the west coast in *** consortium of 5 members was formed in April,*** site will be the largest TCP site in the *** paper describes recent TCP projects in Korea with background and environmental conditions of the projects.

关键词： TCP(Tidal Current Power) ocean energy renewable energy clean energy HAT(Horizontal Axis Turbine) VAT(Vertical Axis Turbine)

Antistatic coating material consisting of poly (butylacrylate-co-styrene) core-nickel shell particle

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中国有色金属学会会刊：英文版 2009年第B9期19卷 119-123页

作者： Min-Yeong JEONG Byung-Yoon AHN Sang-Koul lee Won-Ki lee Nam-Ju jo Department of Polymer Science and Engineering Pusan National University Kumho Petrochemical Samsung Corning Precision Glass Division of Chemical Engineering Pukyong National University

A transparent and antistatic coating material consisting of polymer core-metal shell particle was prepared. As a polymer core, poly(butylacrylate-co-styrene)s ([P(BA-co-sty)s]) with various compositions of butylacrylate and styrene were synthesized by emulsion polymerization. And the effect of comonomer composition on the thermal property of polymer core particle was investigated. By electroless plating method, the nickel particles were formed and deposited on the surface of P(BA-co-Sty) particles to form P(BA-co-Sty) core-nickel shell composite particles. SEM observation confirms that the nickel particles with size of 15 nm are distributed on the surface of the polymer core particles. The surface resistance of P(BA-co-Sty) core-nickel shell composite is 0.8×108Ω/cm2, enough to act as antistatic coating material.

关键词：复合粒子涂层材料单体组成抗静电苯乙烯丁酯聚合物颗粒镍

Understanding the physical metallurgy of the CoCrFeMnNi high-entropy alloy:an atomistic simulation study

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npj Computational Materials 2018年第1期4卷 662-670页

作者： Won-Mi Choi Yong Hee jo Seok Su Sohn Sunghak lee Byeong-joo lee Department of Material Science and Engineering Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea

Although high-entropy alloys(HEAs)are attracting interest,the physical metallurgical mechanisms related to their properties have mostly not been clarified,and this limits wider industrial applications,in addition to the high alloy *** clarify the physical metallurgical reasons for the materials phenomena(sluggish diffusion and micro-twining at cryogenic temperatures)and investigate the effect of individual elements on solid solution hardening for the equiatomic CoCrFeMnNi HEA based on atomistic simulations(Monte Carlo,molecular dynamics and molecular statics).A significant number of stable vacant lattice sites with high migration energy barriers exists and is thought to cause the sluggish *** predict that the hexagonal close-packed(hcp)structure is more stable than the face-centered cubic(fcc)structure at 0 K,which we propose as the fundamental reason for the micro-twinning at cryogenic *** alloying effect on the critical resolved shear stress(CRSS)is well predicted by the atomistic simulation,used for a design of non-equiatomic fcc HEAs with improved strength,and is experimentally *** study demonstrates the applicability of the proposed atomistic approach combined with a thermodynamic calculation technique to a computational design of advanced HEAs.

关键词： alloy alloying entropy

Modeling in Multi-Resolution and Its Applications

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journal of Computer Science & Technology 2006年第2期21卷 272-278页

作者： Sungchan Kim Kunwoo lee Taesik hong Moonki Jung School of Mechanical and Aerospace Engineering Seoul National University San 56-1 Sillim-Dong Gwanak-Gu Seoul 151-752 Korea

It is becoming common for many designers to work together on very complex assemblies in a collaborative environment. To work efficiently in this environment, the capabilities to simplify the portions of an assembly and to reset it to the original resolution should be added to the current CAD systems. Thus operators realizing multi-resolution on B-rep were proposed in previous work. This paper illustrates a prototype multi-resolution system to integrate the proposed operators and its applications. The multi-resolution system can be used in similarity comparisons to reduce the calculation load and to get the full comparison result in the overall shape. Then the features recognized with this system can be used in more detailed comparisons. This system also can be used conceptually to solve security problems in collaborative design.

关键词： collaborative design level of detail multi-resolution similarity comparison

Hypersonic boundary-layer transition on a flared cone

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Acta Mechanica Sinica 2013年第1期29卷 48-53页

作者： Chuan-hong Zhang Qing Tang Cun-Biao lee Department of Aeronautics & Astronautics College of Engineering Peking University

Transition on a flared cone with zero angle of at- tack was studied in our newly established Mach 6 quiet wind tunnel （M6QT） via wall pressure measurement and flow visualization. High-frequency pressure transducers were used to measure the second-mode waves＇ amplitudes and frequencies. Using pulsed schlieren diagnostic and Rayleigh scattering technique, we got a clear evolution of the second-mode disturbances. The second-mode waves exist for a long distance, which means that the second-mode waves grow linearly in a large region. Strong Mach waves are radiated from the edge of the boundary layer. With further development, the second-mode waves reach their maximum magnitude and harmonics of the second-mode instability appear. Then the disturbances grow nonlinearly. The second modes become weak and merge with each other. Finally, the nonlinear interaction of disturbance leads to a relatively quiet zone, which further breaks down, resulting in the transition of the bound- ary layer. Our results show that transition is determined by the second mode. The quiet zone before the final breakdown is observed in flow visualization for the first time. Eventual transition requires the presence of a quiet zone generated by nonlinear interactions.

关键词： PCB pressure sensor - Pulsed schlieren - Flared cone Transition Second-mode waves