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Wiener's lemma:localization and various approaches

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Applied Mathematics(A Journal of Chinese Universities) 2013年第4期28卷 465-484页

作者： shin chang Eon SUN Qi-yu Department of Mathematics Sogang UniversitySeoul 121-742 Korea Department of Mathematics University of Central FloridaOrlando FL 32816 USA

Matrices and integral operators with off-diagonal decay appear in numerous areas of mathematics including numerical analysis and harmonic analysis, and they also play impor-tant roles in engineering science including signal processing and communication engineering. Wiener’s lemma states that the localization of matrices and integral operators are preserved un-der inversion. In this introductory note, we re-examine several approaches to Wiener’s lemma for matrices. We also review briefly some recent advances on localization preservation of operations including nonlinear inversion, matrix factorization and optimization.

关键词： Wiener’s lemma infinite matrix stability Wiener algebra Beurling algebra off-diagonal decay inverse closedness

Programmable Logic Controller Block Monitoring System for Memory Attack Defense in Industrial Control Systems

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Computers, Materials & Continua 2023年第11期77卷 2427-2442页

作者： Mingyu Lee Jiho shin jung Taek Seo Department of Information Security Gachon UniversitySeongnam13120Korea Police Science Institute Korean National Police UniversityAsan31539Korea Department of Computer Engineering Gachon UniversitySeongnam13120Korea

Cyberattacks targeting industrial control systems(ICS)are becoming more sophisticated and advanced than in the past.A programmable logic controller(PLC),a core component of ICS,controls and monitors sensors and actuators in the ***,PLC has memory attack threats such as program injection and manipulation,which has long been a major target for attackers,and it is important to detect these attacks for ICS *** detect PLC memory attacks,a security system is required to acquire and monitor PLC memory *** addition,the performance impact of the security system on the PLC makes it difficult to apply to the *** address these challenges,this paper proposes a system to detect PLC memory attacks by continuously acquiring and monitoring PLC *** proposed system detects PLC memory attacks by acquiring the program blocks and block information directly from the same layer as the PLC and then comparing them in bytes with previous *** with Siemens S7-300 and S7-400 PLC were conducted to evaluate the PLC memory detection performance and performance impact on *** experimental results demonstrate that the proposed system detects all malicious organization block(OB)injection and data block(DB)manipulation,and the increment of PLC cycle time,the impact on PLC performance,was less than 1 *** proposed system detects PLC memory attacks with a simpler detection method than earlier ***,the proposed system can be applied to ICS with a small performance impact on PLC.

关键词： Programmable logic controller industrial control system attack detection

Effects of Cordyceps militaris extract on angiogenesis and tumor growth

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Acta Pharmacologica Sinica 2004年第5期25卷 115-123页

作者： Hwa-seung YOO,Jang-woo shin,jung-hyo CHO,chang-gue SON,Yeon-weol LEE,Sang-yong PARK,Chong-kwan CHO Daejeon University Daejeon 301-724 Department of East-West Cancer Center College of Oriental Medicine Daejeon University Daejeon 301-724 Department of East-West Cancer Center College of Oriental Medicine Daejeon University Daejeon 301-724 Department of East-West Cancer Center R&D Lab of Bulrolife Co Ltd Daejeon Korea College of Oriental Medicine Daejeon University Daejeon 301-724 Institute ofTraditional Medicine and Bioscience Daejeon University Daejeon 301-724 Department of East-West Cancer Center College of Oriental Medicine

AIM: To evaluate the effects of Cordyceps militaris extract (CME) on angiogenesis and tumor growth. METHODS:Human umbilical vein endothelial cells (HUVEC), HT1080, and B16-F10 cells were used. DNA fragment, angio-genic related gene expressions (MMPs, bFGF, VEGF, etc), capillary tube formation, wound healing in vitro, tumorgrowth in vivo were measured. RESULTS: CME inhibited growth of HUVECs and HT1080 (P<0.01). CME 100and 200 mg/L reduced MMP-2 gene expression in HT1080 cells by 6.0 % and 22.9 % after 3-h and 14.9 % and32.8 % after 6-h treatment. CME did not affect MMP-9 gene expression in B16-F10 melanoma cells. CME 100 and200 mg/L also reduced bFGF gene expression in HUVECs by 22.2 % and 41.3 %. CME inhibited tube formation ofendothelial cells in vitro and in vivo. CME repressed the growth of B16-F10 melanoma cells in mice compared withcontrol group (P<0.05). CONCLUSION: CME has antiangiogenetic properties.

关键词： Cordyceps militaris angiogenesis human umbilical vein endothelial cells HT1080 cells B16-F10cells matrix metalloproteinases basic fibroblast growth factor

Patterns and determinants of plant richness by elevation in a mountain ecosystem in South Korea: area, mid-domain effect,climate and productivity

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Journal of Forestry Research 2015年第4期26卷 905-917页

作者： chang-Bae Lee jung-Hwa Chun Korea Green Promotion Agency 121 DunsanbukroSeoguDaejeon 302-831Republic of Korea Division of Forest Ecology Korea Forest Research Institute57 HoegiroDongdaemunguSeoul 130-712Republic of Korea

We examined patterns of plant species richness on an elevation gradient and evaluated the effects of cli- matic variables including mean annual temperature and precipitation, area, the mid-domain effect and productivity on species richness along two transects on Mt. Seorak, South Korea. A total of 235 plant species of 72 families and 161 genera were recorded from 130 plots along the two transects. Two different patterns, monotonic decline and a unimodal shape, were observed for woody plants with the change in elevation along the two transects, whereas multimodal patterns were observed for all plant species considered together and for herbaceous plants. Area and productivity showed significant relationships with total plant richness. Climatic variables were better predictors than other variables for variation by elevation in woody plant richness, whereas productivity was a more important variable for herbaceous plant richness. Although area was an important variable for predicting species richness pat- terns, the effects differed by transect and plant group. No empirical evidence was linked to the mid-domain *** elevational patterns may characterize different groups in the same taxon and there might be fundamental differences in the mechanisms underlying these richness patterns.

关键词： Area Climatic variables Elevationalpatterns Plant richness Productivity

Sorption enhanced catalytic CF4 hydrolysis with a three-stage catalyst-adsorbent reactor

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Frontiers of Chemical Science and Engineering 2017年第4期11卷 537-544页

作者： Jae-Yun Han chang-Hyun Kim Boreum Lee Sung-Chan Nam Ho-Young jung Hankwon Lim Kwan-Young Lee shin-Kun Ryi . Advanced Materials and Devices Laboratory Korea Institute of Energy Research (KIER) Daejeon 34129 Korea.. Department of Advanced Materials and Chemical Engineering Catholic University of Daegu Gyeongbuk 38430 Korea.. Department of Environment and Energy Engineering Chonnam National University Gwangju 61186 Korea.. Department of Chemical and Biological Engineering Korea University Seoul 136-701 Korea

In this study, we developed a three-stage catalyst-adsorbent reactor for the catalytic hydrolysis of CF4. Each stage is composed of a catalyst bed followed by an adsorbent bed using Ca（OH）2 to remove HF. The three stages are connected in series to enhance the hydrolysis of CF4 and eliminate a scrubber to dissolve HF in water at the same time. With a 10 wt-% Ce/AlaO3 catalyst prepared by the incipient wetness method using boehmite and a granular calcium hydroxide as an adsorbent, the CF4 conversion in our proposed reactor was 7%-23% higher than that in a conventional single-bed catalytic reactor in the temperature range of 923-1023 K. In addition, experimental and numerical simulation （Aspen HYSYS） results showed a reasonable trend of increased CF4 conversion with the adsorbent added and these results can be used as a useful design guideline for our newly proposed multistage reactor system.

关键词： PFCs catalytic hydrolysis calcium hydro-xide sorption enhanced process simulation

Diversity patterns and phylogenetic structure of vascular plants along elevational gradients in a mountain ecosystem, South Korea

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Journal of Mountain Science 2018年第2期15卷 280-295页

作者： CHUN jung-Hwa LEE chang-Bae Division of Forest Ecology National Institute of Forest Science Global Resources Division Korea Forestry Promotion Institute

Recently, a phylogenetic diversity and community structure analysis as complementary to species-centric approaches in biodiversity studies provides new insights into the processes of community assembly. In this study, we analyzed species and phylogenetic diversity and community structures for woody and herbaceous plants along two elevational transects on Mt. Baekhwa, South Korea. The species richness and phylogenetic diversity of woody plants showed monotonic declining patterns with increasing elevation along all transects, whereas herbaceous plants showed different patterns, such as no relationship and a reversed unimodal pattern, between the study transects. The main drivers of these patterns were climate and habitat variables for woody and herbaceous plants, respectively. In addition, the phylogenetic community structure primarily showed phylogenetic clustering regulated by deterministic processes, especially environmental filtering, such as climate or habitat factors, along the two transects, although herbaceous plants along a transect depicted phylogenetic randomness as a result of a neutral process. Our findings suggest that deterministic and neutral processes may simultaneously control the community structures along small-scale elevational gradients such as local transects, although the deterministic process may be the predominant type.

关键词： Community structure Deterministicprocess Elevational gradient Neutral process Phylogenetic diversity Species richness

Solar Power Plant Network Packet-Based Anomaly Detection System for Cybersecurity

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Computers, Materials & Continua 2023年第10期77卷 757-779页

作者： Ju Hyeon Lee Jiho shin jung Taek Seo Department of Information Security Gachon UniversitySeongnam13120Korea Police Science Institute Korean National Police UniversityAsan31539Korea Department of Computer Engineering Gachon UniversitySeongnam13120Korea

As energy-related problems continue to emerge,the need for stable energy supplies and issues regarding both environmental and safety require urgent *** energy is becoming increasingly important,with solar power accounting for the most significant proportion of *** the scale and importance of solar energy have increased,cyber threats against solar power plants have also ***,we need an anomaly detection system that effectively detects cyber threats to solar power ***,as mentioned earlier,the existing solar power plant anomaly detection system monitors only operating information such as power generation,making it difficult to detect *** address this issue,in this paper,we propose a network packet-based anomaly detection system for the Programmable Logic Controller(PLC)of the inverter,an essential system of photovoltaic plants,to detect cyber *** and vulnerabilities in solar power plants were analyzed to identify cyber threats in solar power *** analysis shows that Denial of Service(DoS)and Manin-the-Middle(MitM)attacks are primarily carried out on inverters,aiming to disrupt solar plant *** develop an anomaly detection system,we performed preprocessing,such as correlation analysis and normalization for PLC network packets data and trained various machine learning-based classification models on such *** Random Forest model showed the best performance with an accuracy of 97.36%.The proposed system can detect anomalies based on network packets,identify potential cyber threats that cannot be identified by the anomaly detection system currently in use in solar power plants,and enhance the security of solar plants.

关键词： Renewable energy solar power plant cyber threat cybersecurity anomaly detection machine learning network packet

Novel Intense-pulsed-light synthesis of amorphous SnO_(2)electron-selective layers for efficient planar MAPbI_(3)perovskite solar cells

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Journal of Materials Science & Technology 2021年第33期92卷 171-177页

作者： Kwonwoo Oh Kyungeun jung Jaehak shin Sunglim Ko Man-Jong Lee Department of Chemistry Konkuk UniversitySeoul 143-701Republic of Korea Department of Advanced Technology Fusion Konkuk UniversitySeoul 143-701Republic of Korea Department of Mechanical Design and Production Engineering Konkuk UniversitySeoul 143-701Republic of Korea

Although perovskite solar cells(PSCs)have achieved a high power conversion efficiency(PCE)within a short period of development,the high-temperature sintering of the constituent electron-selective layers(ESLs)impedes the *** this report,we demonstrate the effectiveness of an intensepulsed-light(IPL)treatment for the rapid and damage-free sintering of amorphous-SnO_(2)ESLs for use in *** IPL treatment of amorphous-SnO_(2)substantially reduced the amount of surface hydroxyl groups,modified the surface energy,and enabled the growth of a low-stress perovskite layer with large grain sizes,all of which enhanced the photovoltaic properties and led to the proper alignment of band structures for efficient *** comprehensive optimization of the IPL conditions,a PCE of 17.68%was achieved from the MAPb I3 planar PSC based on an amorphous-SnO_(2)IPL treated for a few tens of seconds,which was significantly increased compared with a PCE(7.06%)of nontreated SnO_(2)based *** addition,the PCE of the IPL-treated SnO_(2)based PSC is comparable to the best PCE(18.16%)of PSCs fabricated with SnO_(2)ESL annealed for three hours at 185℃.Because of its ultrafast sintering time and tendency to not damage SnO_(2)ESLs,the new IPL process is expected to open new opportunities for the commercialization of PSCs.

关键词： Perovskite solar cells Intense pulsed light Amorphous SnO_(2) Electron-selective layer Internal stress

Optimal three-dimensional impact time guidance with seeker’s field-of-view constraint

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Chinese Journal of Aeronautics 2021年第2期34卷 240-251页

作者： Shaoming HE chang-Hun LEE Hyo-Sang shin Antonios TSOURDOS School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Department of Aerospace Engineering Korea Advanced Institute of Science and TechnologyDaejeon 34141Republic of Korea School of Aerospace Transport and ManufacturingCranfield UniversityCranfiehMK43 OALUnited Kingdom

This paper proposes a new three-dimensional optimal guidance law for impact time control with seeker’s Field-of-View(FOV) constraint to intercept a stationary target. The proposed guidance law is devised in conjunction with the concept of biased Proportional Navigation Guidance(PNG). The guidance law developed leverages a nonlinear function to ensure the boundedness of velocity lead angle to cater to the seeker’s FOV limit. It is proven that the impact time error is nullified in a finite-time under the proposed method. Additionally, the optimality of the biased command is theoretically analyzed. Numerical simulations confirm the superiority of the proposed method and validate the analytic findings.

关键词： Applied optimal control Field-of-view constraint Impact time control Missile guidance Optimal error dynamics