• Genomics & Informatics
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• v.21 no.3
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• pp.41.1-41.11
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• 2023

The Dengue virus M protein is a 75 amino acid polypeptide with two helical transmembranes (TM). The TM domain oligomerizes to form an ion channel, facilitating viral release from the host cells. The M protein has a critical role in the virus entry and life cycle, making it a potent drug target. The oligomerization of the monomeric protein was studied using ab initio modeling and molecular dynamics simulation in an implicit membrane environment. The representative structures obtained showed pentamer as the most stable oligomeric state, resembling an ion channel. Glutamic acid, threonine, serine, tryptophan, alanine, isoleucine form the pore-lining residues of the pentameric channel, conferring an overall negative charge to the channel with approximate length of 51.9 Å. Residue interaction analysis for M protein shows that Ala94, Leu95, Ser112, Glu124, and Phe155 are the central hub residues representing the physicochemical interactions between domains. The virtual screening with 165 different ion channel inhibitors from the ion channel library shows monovalent ion channel blockers, namely lumacaftor, glipizide, gliquidone, glisoxepide, and azelnidipine to be the inhibitors with high docking scores. Understanding the three-dimensional structure of M protein will help design therapeutics and vaccines for Dengue infection.

• Convergence Security Journal
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• v.23 no.5
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• pp.73-79
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• 2023

Cyber threats are evolving and becoming more sophisticated with the development of new technologies, and consequently the number of service failures caused by DDoS attacks are continually increasing. Recently, DDoS attacks have numerous types of service failures by applying a large amount of traffic to the domain address of a specific service or server. In this paper, after generating the data of the Syn Flooding attack, which is the representative attack type of bandwidth exhaustion attack, the data were compared and analyzed using Random Forest, Decision Tree, Multi-Layer Perceptron, and KNN algorithms for the effective detection of attacks, and the optimal algorithm was derived. Based on this result, it will be useful to use as a technique for the detection policy of Syn Flooding attacks.

• The Journal of Engineering Geology
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• v.22 no.4
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• pp.459-466
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• 2012

A difficulty encountered in engineering seismic mapping is that reflection events from shallow discontinuities are commonly overlapped with coherent noise such as air wave, direct waves, head waves, and high-amplitude surface waves. Here, the radial trace transform, a simple geometric re-mapping of a trace gather (x-t domain) to another trace gather (v-t domain), is applied to investigate the rejection effect of coherent linear noises. Two different types of data sets were selected as a representative database: good-quality data for intermediate sounding (hundreds of meters) in a sedimentary basin and very noisy data for shallow (${\leq}50m$) mapping of the weathered zone and bedrock surface. Results obtained with cascaded application of the radial transform and low-cut filtering proved to be as good as, or better than, those produced using f-k filtering, and were especially effective for air wave and direct wave. This simple transform enables better understanding of the characteristics of various types of noise in the RT domain, and can be generally applied to overcoming diffractions and back-scatterings caused by joints, fractures, and faults commonly that are encountered in geotechnical problems.

• Journal of Korean Library and Information Science Society
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• v.54 no.1
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• pp.143-165
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• 2023

This study aims to propose a scaffolding strategy that can be applied to the information search process by using Kuhlthau's ISP model, which presented a design and implementation strategy for the mediation role in the learning process. To this end, the relevant literature was reviewed to categorize scaffolding strategies, and impressions were collected from the students surveys after providing 150 middle school students in the Daejeon area with the project class to which the scaffolding strategy based on the ISP model was applied. The collected data were processed into a form suitable for analysis through data preprocessing for word frequencies to be extracted, and topic analysis was performed using STM (Structural Topic Modeling). First, after determining the optimal number of topics and extracting topics for each stage of the ISP model, the extracted topics were classified into three types: cognitive domain-macro perspective, cognitive domain-micro perspective, and emotional domain perspective. In this process, we focused on cognitive verbs and emotional verbs among words extracted through text mining, and presented a scaffolding strategy model related to each topic by reviewing representative document cases. Based on the results of this study, if an appropriate scaffolding strategy is provided at the ISP model stage, a positive effect on learners' self-directed task solving can be expected.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.1
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• pp.237-244
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• 2009

We investigated the effects of acupuncture stimulation on pulse wave variables and heart rate variability (HRV) in healthy adults. To evaluate twenty healthy volunteers (10 men, 10 women) had acupuncture into both Hapkok (Ll4) and Taechung (Liv3) for 15 minutes. Radial pulse, Heart Rate Variability, body temperature and blood pressure were checked before and after acupuncture to evaluate Pulse Wave Variability and Autonomous Function. The results were as follows; Heart rate was significantly increased while systolic blood pressure (mmHg) and diastolic blood pressure (mmHg) were significantly increased after acupuncture treatment. Sixteen subjects didn't change representative pulse wave variables after acupuncture treatment. Energy, height of main peak (H1), height of pre-dicrotic valley (H2) and height of descending valley (H4) were decreased while height of dicrotic peak (H5) was significantly decreased after acupuncture treatment. Time to main peak (T1), time to pre-dicrotic valley (T2), time to dicrotic peak (T5), total time (T) and T-T4 were decreased while time to descending valley (T4) was increased after acupuncture treatment. Total area (At), area of main peak (Aw) and ratio of diastolic period area (Ad) were decreased while ratio of systolic period area (As) and angle of main peak (MPA) were increased after acupuncture treatment. The standard deviation of all normal RR intervals (SDNN) was increased while the root mean square of successive differences between the normal heart beats (RMSSD) was significantly increased after acupuncture treatment by time domain analysis. Low frequency power (LF) and LF/HF ratio were decreased while high frequency power (HF) was significantly increased after acupuncture treatment by frequency domain analysis. This study suggests that acupuncture treatment changes pulse wave variability and heart rate variability. Further study on various acupuncture treatment for pulse wave variability and heart rate variability is required.

• Journal of KIISE:Information Networking
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• v.32 no.4
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• pp.515-524
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• 2005

As the number of the mobile nodes (MNs) increases in the networks, the signaling traffic generated by mobility management for MNs will increase explosively, and such a phenomenon will probably affect overall network performance. In this paper, we propose a novel analytical approach using a continuous-time Markov chain model and hierarchical network model for the analysis on the signaling load of representative IPv6 mobility support Protocols such as Mobile IPv6 (MIPv6) and Hierarchical Mobile IPv6 (HMIPv6). According to these analytical modeling, this paper derives the various signaling costs, which are generated by an MN during its average domain residence time when MIPv6 and HMIPv6 are deployed under the same network architecture, respectively. In addition, based on these derived costs, we investigate the effects of various mobility/traffic-related parameters on the signaling costs generated by an MN under MIPv6 and HMIPv6. The analytical results show that as the average moving speed of an MN gets higher and the binding lifetime is set . to the larger value, and as its average packet arrival rate gets lower, the total signaling cost generated during its average domain residence time under HMIPv6 will get relatively lower than that under MIPv6, and that under the reverse conditions, the total signaling cost under MIPv6 will get relatively lower than that under HMIPv6.

• The Journal of the Petrological Society of Korea
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• v.18 no.2
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• pp.115-135
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• 2009

We have studied general orientational characteristics of microcracks distributed in Tertiary crystalline tuff from the northeastern part of the Gyeongsang Basin. 108 sets of microcracks on horizontal surfaces of 6 rock samples from Heunghae-eup and Cheongha-myeon, Pohang-si areas were distinguished by image processing. Those microcrack sets show a distinct linear array in 38 images. Whole domain of the directional angle(${\theta}$)-frequency(N) chart for crystalline tuff can be divided into 20 domains in terms of the phases of the distribution of microcracks. From the related chart, microcrack sets show preferred orientation which are coincident with the direction of vertical common joints. Consequently, the potential for macroscopic vertical joints in a rock body can be inferred from the directional angle showing high frequency in each domain of the related chart. This joint pattern is nearly the same in Mesozoic granites from Seokmo-do, Gwanghwa-gun. From the rose diagram for orientations of microcrack in crystalline tuff, orientations of dominant sets of microcracks in terms of frequency orders reflect representative orientations of maximum principal stress acted on crystalline tuff. Meanwhile, orientations of microcracks in crystalline tuff were compared with those of open microcracks in Bulgugsa granites from the southwestern part of the Gyeongsang Basin, and vertical rift/grain planes from Mesozoic granite quarries in Korea. In regional distribution chart, the agreement of distribution pattern between above two types of microcrack sets and vertical planes suggests that microcrack systems developed in crystalline tuff probably occur regionally in Mesozoic granites in Korea.

• Journal of Broadcast Engineering
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• v.13 no.6
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• pp.892-904
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• 2008

As a video encoding in resource constrained environments such as sensor networks has become an important issue, DVC(Distributed Video Coding) has been intensively investigated as a solution for light weighted video encoding problem. Known as one of the representative schemes of DVC, the Wyner-Ziv coding generates side information of current frame only at decoder, using correlation among frames, and reconstructs video through noise elimination on the side information using channel code. Accordingly, the better quality of side information brings less channel noise, thus attains better coding performance of the Wyner-Ziv coder. However, since it is hard for decoder to generate an accurate side information without any information of original frame, a method to successively improve side information using successively decoded original frame, based on decoding reliability, was previously developed. However, to improve side information from decoding results, not only an error rate of the decoding result as a reliability, but also the amount of reliable information from the decoding result is important. Therefore, we propose TDWZ(Transform-domain Wyner-Ziv coding) with successively improving side information based on decoding reliability considering not only an error rate but also the amount of reliable information of the decoding results. Our experiment shows the proposed method gains average PSNR up to 1.7 dB over the previous TDWZ, that is without successive side information improvement.

• Journal of Korean Elementary Science Education
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• v.24 no.5
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• pp.546-557
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• 2005

The purpose of this study was to analyze the characteristics of the geology-related contents in the 1st~7th elementary science curriculum. Our analysis was based on the analytical frameworks of geology-related contents (the structure of the contents, the amount of teaming, the contents of the experimental activities, the transitions of the terminology, and the change in the number of illustrations). The results are as follows: 1. Consistently covered contents were limited to weathering of the rock and soil, igneous rock, sedimentary rock, metamorphic rock, and the change of the earth's, fold and fault, earthquake and volcano, geologic stratum and fossil. 2. The geological contents account for (average), 11.5% (maximum), and 5.1% (minimum) of the elementary science curriculum. Most contents covered in the curriculum were rock and soil, and the change of the earth's surface. 3. Continuously covered experimental contents were the weathering and soil, igneous rock, change of the earth's surface, geologic stratum and fossil. 4. The terminology on the rock was the most frequently changed. Whenever the curriculum changed, the addition, deletion, or renaming of terminology led to confusions. 5. In terms of the transition of illustrations, the pictures replaced the figures or diagrams as the representative illustration methods as the science or the textbook compilation skill develope. The cartoons or tables were also used increasingly in order to help the children to understand and pay attention to study.

• The Journal of the Petrological Society of Korea
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• v.17 no.4
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• pp.206-221
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• 2008

We have studied general orientational characteristics of microcracks distributed in Bulgugsa Granites of southwestern Gyeongsang Basin. Microcracks of 131 sets, which were developed on horizontal surfaces of II rock samples collected from Sacheon-Gosung, Geoje-si and Namhae-gun areas, were distinguished by image processing. Then, 45 sets with a distinct linear array on image were sorted out. These microcracks can be comparable with vertical grain planes. Orientations of these microcracks were compared with those of vertical rift and grain planes developed in Cretaceous and Jurassic granites of Korea. In the distribution chart, the agreement of the distribution pattern between microcracks of 45 sets and above vertical planes suggests that microcrack systems developed all over the study area also occur regionally in Cretaceous and Jurassic granites of Korea. Whole domain of the directional angle-frequency chart can be divided into 20 domains in terms of the phases of the distribution of microcracks. Meanwhile, 18 domains from 45 sets of microcracks were compared with the maximum principal stress orientations suggested from previous studies. The majority of maximum principal stress orientations pertain to domain $1{\sim}2$, $5{\sim}6$, $11{\sim}15$, $17{\sim}18$ and $19{\sim}20$, and these domains are coincident with the orientation of the 1st and 2nd-frequency orders represented in a rose diagram for 45 sets of microcracks. Representative orientations of open microcrack reflect the maximum principal stress orientations suggested in previous studies.