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Keypoint-based Deep Learning Approach for Building Footprint Extraction Using Aerial Images

  • Jeong, Doyoung;Kim, Yongil
    • Korean Journal of Remote Sensing
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    • v.37 no.1
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    • pp.111-122
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    • 2021
  • Building footprint extraction is an active topic in the domain of remote sensing, since buildings are a fundamental unit of urban areas. Deep convolutional neural networks successfully perform footprint extraction from optical satellite images. However, semantic segmentation produces coarse results in the output, such as blurred and rounded boundaries, which are caused by the use of convolutional layers with large receptive fields and pooling layers. The objective of this study is to generate visually enhanced building objects by directly extracting the vertices of individual buildings by combining instance segmentation and keypoint detection. The target keypoints in building extraction are defined as points of interest based on the local image gradient direction, that is, the vertices of a building polygon. The proposed framework follows a two-stage, top-down approach that is divided into object detection and keypoint estimation. Keypoints between instances are distinguished by merging the rough segmentation masks and the local features of regions of interest. A building polygon is created by grouping the predicted keypoints through a simple geometric method. Our model achieved an F1-score of 0.650 with an mIoU of 62.6 for building footprint extraction using the OpenCitesAI dataset. The results demonstrated that the proposed framework using keypoint estimation exhibited better segmentation performance when compared with Mask R-CNN in terms of both qualitative and quantitative results.

A Study on FIDO UAF Federated Authentication Using JWT Token in Various Devices (다양한 장치에서 JWT 토큰을 이용한 FIDO UAF 연계 인증 연구)

  • Kim, HyeongGyeom;Kim, KiCheon
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.16 no.4
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    • pp.43-53
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    • 2020
  • There are three standards for FIDO1 authentication technology: Universal Second Factor (U2F), Universal Authentication Framework (UAF), and Client to Authenticator Protocols (CTAP). FIDO2 refers to the WebAuthn standard established by W3C for the creation and use of a certificate in a web application that complements the existing CTAP. In Korea, the FIDO certified market is dominated by UAF, which deals with standards for smartphone (Android, iOS) apps owned by the majority of the people. As the market requires certification through FIDO on PCs, FIDO Alliance and W3C established standards that can be certified on the platform-independent Web and published 『Web Authentication: An API for Accessing Public Key Credentials Level 1』 on March 4, 2019. Most PC do not contain biometrics, so they are not being utilized contrary to expectations. In this paper, we intend to present a model that allows login in PC environment through biometric recognition of smartphone and FIDO UAF authentication. We propose a model in which a user requests login from a PC and performs FIDO authentication on a smartphone, and authentication is completed on the PC without any other user's additional gesture.

Crystallinity of Low Molar Ratio Urea-Formaldehyde Resins Modified with Cellulose Nanomaterials

  • PARK, Seongsu;PARK, Byung-Dae
    • Journal of the Korean Wood Science and Technology
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    • v.49 no.2
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    • pp.169-180
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    • 2021
  • Inherent crystalline domains present in low formaldehyde to urea (F/U) molar ratio urea-formaldehyde (UF) resins are responsible for their poor adhesion in wood-based composite panels. To modify the crystallinity of low molar ratio (LMR) UF resins, this study investigates the additional effect of cellulose nanomaterials (CNMs), such as cellulose microfibrils (CMFs), cellulose nanofibrils (CNFs), and TEMPO-oxidized CNFs (TEMPO-CNFs) on the crystallinity of modified LMR UF resins. First, two modification methods (post-mixing and in situ) were compared for modified LMR UF resins with TEMPO-CNFs. The modified UF resins with TEMPO-CNFs decreased the nonvolatile solid contents, while increasing the viscosity and gel time. However, the in situ modification of UF resins with TEMPO-CNFs showed lower crystallinity than that of post-mixing. Then, the in situ method was compared for all CNMs to modify LMR UF resins. The modified UF resins with CMFs using the in situ method increased nonvolatile solid contents and viscosity but decreased the gel time. The crystallinity of UF resins modified with TEMPO-CNFs was the lowest even though the crystalline domains were not significantly changed for all modified UF resins. These results suggest that these CNMs should be modified to prevent the formation of crystalline domains in LMR UF resins.

Development and effects of sexually transmitted disease prevention programs for the elderly (노인 성병예방 프로그램 개발 및 효과)

  • Bae, Young Soon;Shon, Kyoung Hee;Kim, Nam Hee
    • Journal of Korean Public Health Nursing
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    • v.35 no.2
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    • pp.239-253
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    • 2021
  • Purpose: An STD (Sexually transmitted disease) prevention program was developed for the elderly, and its effect on their knowledge about STDs, STD prevention attitudes, social support, STD prevention self-efficacy, STD prevention behaviors, and STD presence were verified. Method: The subjects of the study were 50 people (25 in the experimental group and 25 in the control group). The experimental group was provided with a six-session STD prevention program. Result: In the experimental group, the knowledge about STD (t=105.00, p<.001), STD prevention attitudes (t=7.60, p<.001), and social support (F=87.11, p<.001), STD prevention self-efficacy (U=28.00, p<.001), and STD prevention behavior (t=7.38, p<.001) were improved significantly. Conclusion: The results highlight the need for nursing intervention for STD prevention to the elderly using the program developed for the prevention of STDs for the elderly.

Interface Trap Effects on the Output Characteristics of GaN Schottky Barrier MOSFET (GaN Schottky Barrier MOSFET의 출력 전류에 대한 계면 트랩의 영향)

  • Park, Byeong-Jun;Kim, Han-Sol;Hahm, Sung-Ho
    • Journal of Sensor Science and Technology
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    • v.31 no.4
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    • pp.271-277
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    • 2022
  • We analyzed the effects of the interface trap on the output characteristics of an inversion mode n-channel GaN Schottky barrier (SB)-MOSFET based on the Nit distribution using TCAD simulation. As interface trap number density (Nit) increased, the threshold voltage increased while the drain current density decreased. Under Nit=5.0×1010 cm-2 condition, the threshold voltage was 3.2 V for VDS=1 V, and the drain current density reduced to 2.4 mA/mm relative to the non-trap condition. Regardless of the Nit distribution type, there was an increase in the subthreshold swing (SS) following an increase in Nit. Under U-shaped Nit distribution, it was confirmed that the SS varied depending on the gate voltage. The interface fixed charge (Qf) caused an shift in the threshold voltage and increased the off-state current collectively with the surface trap. In summary, GaN SB-MOSFET can be a building block for high power UV optoelectronic circuit provided the surface state is significantly reduced.

An Efficient Machine Learning-based Text Summarization in the Malayalam Language

  • P Haroon, Rosna;Gafur M, Abdul;Nisha U, Barakkath
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.6
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    • pp.1778-1799
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    • 2022
  • Automatic text summarization is a procedure that packs enormous content into a more limited book that incorporates significant data. Malayalam is one of the toughest languages utilized in certain areas of India, most normally in Kerala and in Lakshadweep. Natural language processing in the Malayalam language is relatively low due to the complexity of the language as well as the scarcity of available resources. In this paper, a way is proposed to deal with the text summarization process in Malayalam documents by training a model based on the Support Vector Machine classification algorithm. Different features of the text are taken into account for training the machine so that the system can output the most important data from the input text. The classifier can classify the most important, important, average, and least significant sentences into separate classes and based on this, the machine will be able to create a summary of the input document. The user can select a compression ratio so that the system will output that much fraction of the summary. The model performance is measured by using different genres of Malayalam documents as well as documents from the same domain. The model is evaluated by considering content evaluation measures precision, recall, F score, and relative utility. Obtained precision and recall value shows that the model is trustable and found to be more relevant compared to the other summarizers.

Impacts of Burden from Behavioral Psychological Symptoms of Dementia, Dementia Attitude, and Emotional Labor on Caring Behavior of Nurses in Long-term Care Hospital (요양병원 간호사의 치매 행동심리증상 부담감, 치매태도 및 감정노동이 돌봄행위에 미치는 영향)

  • Eo, Hye Kyung;Kim, Seonho
    • Journal of muscle and joint health
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    • v.28 no.2
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    • pp.111-120
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    • 2021
  • Purpose: This study was a descriptive research to identify the relationships among burden from behavioral psychological symptoms of dementia, dementia attitude, emotional labor and nurse's caring behavior as well as to clarify factors that affect caring behavior of nurses in long-term care hospital. Methods: For the research, this study collected data from July 8 to July 20, in 2019 with 214 nurses who worked at 10 long-term care hospitals in Chungbuk. The data were analyzed using descriptive statistics, t-tests, Mann-Whitney U test, ANOVA, Pearson's correlation coefficient, stepwise multiple regression with the SPSS 23.0 program. Results: Factors influencing caring behavior of nurses in long-term care hospital were dementia attitudes (β=.549, p<.001), burden from behavioral psychological symptoms of dementia (β=.242, p<.001) and marital status (β=.134, p=.017). These factors explained 33.9% of caring behavior (F=37.35, p<.001). Conclusion: Dementia attitudes were confirmed to be the main variable influencing nurse's caring behavior. Therefore, to improve the caring behavior of dementia patient, it is considered that the development of programs to improve dementia attitudes and in-depth understanding regarding the behavioral and psychological symptoms of dementia is necessary.

In silico discovery and evaluation of phytochemicals binding mechanism against human catechol-O-methyltransferase as a putative bioenhancer of L-DOPA therapy in Parkinson disease

  • Rath, Surya Narayan;Jena, Lingaraja;Bhuyan, Rajabrata;Mahanandia, Nimai Charan;Patri, Manorama
    • Genomics & Informatics
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    • v.19 no.1
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    • pp.7.1-7.13
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    • 2021
  • Levodopa (L-DOPA) therapy is normally practised to treat motor pattern associated with Parkinson disease (PD). Additionally, several inhibitory drugs such as Entacapone and Opicapone are also cosupplemented to protect peripheral inactivation of exogenous L-DOPA (~80%) that occurs due to metabolic activity of the enzyme catechol-O-methyltransferase (COMT). Although, both Entacapone and Opicapone have U.S. Food and Drug Administration approval but regular use of these drugs is associated with high risk of side effects. Thus, authors have focused on in silico discovery of phytochemicals and evaluation of their effectiveness against human soluble COMT using virtual screening, molecular docking, drug-like property prediction, generation of pharmacophoric property, and molecular dynamics simulation. Overall, study proposed, nine phytochemicals (withaphysalin D, withaphysalin N, withaferin A, withacnistin, withaphysalin C, withaphysalin O, withanolide B, withasomnine, and withaphysalin F) of plant Withania somnifera have strong binding efficiency against human COMT in comparison to both of the drugs i.e., Opicapone and Entacapone, thus may be used as putative bioenhancer in L-DOPA therapy. The present study needs further experimental validation to be used as an adjuvant in PD treatment.

Climatology of Equatorial Plasma Bubbles in Ionospheric Connection Explorer/Far-UltraViolet (ICON/FUV) Limb Images

  • Park, Jaeheung;Mende, Stephen B.;Eastes, Richard W.;Frey, Harald U.
    • Journal of Astronomy and Space Sciences
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    • v.39 no.3
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    • pp.87-98
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    • 2022
  • The Far-UltraViolet (FUV) imager onboard the Ionospheric Connection Explorer (ICON) spacecraft provides two-dimensional limb images of oxygen airglow in the nightside low-latitude ionosphere that are used to determine the oxygen ion density. As yet, no FUV limb imager has been used for climatological analyses of Equatorial Plasma Bubbles (EPBs). To examine the potential of ICON/FUV for this purpose, we statistically investigate small-scale (~180 km) fluctuations of oxygen ion density in its limb images. The seasonal-longitudinal variations of the fluctuation level reasonably conform to the EPB statistics in existing literature. To further validate the ICON/FUV data quality, we also inspect climatology of the ambient (unfiltered) nightside oxygen ion density. The ambient density exhibits (1) the well-known zonal wavenumber-4 signatures in the Equatorial Ionization Anomaly (EIA) and (2) off-equatorial enhancement above the Caribbean, both of which agree with previous studies. Merits of ICON/FUV observations over other conventional data sets are discussed in this paper. Furthermore, we suggest possible directions of future work, e.g., synergy between ICON/FUV and the Global-scale Observations of the Limb and Disk (GOLD) mission.

MESHLESS AND HOMOTOPY PERTURBATION METHODS FOR ONE DIMENSIONAL INVERSE HEAT CONDUCTION PROBLEM WITH NEUMANN AND ROBIN BOUNDARY CONDITIONS

  • GEDEFAW, HUSSEN;GIDAF, FASIL;SIRAW, HABTAMU;MERGIAW, TADESSE;TSEGAW, GETACHEW;WOLDESELASSIE, ASHENAFI;ABERA, MELAKU;KASSIM, MAHMUD;LISANU, WONDOSEN;MEBRATE, BENYAM
    • Journal of applied mathematics & informatics
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    • v.40 no.3_4
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    • pp.675-694
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    • 2022
  • In this article, we investigate the solution of the inverse problem for one dimensional heat equation with Neumann and Robin boundary conditions, that is, we determine the temperature and source term with given initial and boundary conditions. Three radial basis functions(RBFs) have been used for numerical solution, and Homotopy perturbation method for analytic solution. Numerical solutions which are obtained by considering each of the three RBFs are compared to the exact solution. For appropriate value of shape parameter c, numerical solutions best approximates exact solutions. Furthermore, we have shown the impact of noisy data on the numerical solution of u and f.