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Metaverse Technology and Security Threats and Countermeasures (메타버스 기술과 보안 위협 및 대응방안)

  • Woo, SungHee;Lee, HyoJeong
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2022.10a
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    • pp.328-330
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    • 2022
  • Currently, the Metaverse is introduced in various fields, and a virtual convergence economy that uses NFTs for content or item transactions is expected to develop into a 'metaverse environment'. The 'metaverse environment' will lead the changes in our society in the future and it will be fused with AI, big data, cloud, IoT, block chain, and next-generation network technology. However, personal information, device information, and behavior information provided by Metaverse users to use the service are subject to major attacks. Therefore, in order to provide a safe environment for users to use and to expand the business base of related companies, building a public-private cooperation system and developing a security guide are the leading tasks. Therefore, in this study, we compare and analyze metaverse features and technologies, and examine possible security threats and countermeasures.

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A Study on the Acceptability of Digital Transformation in the Port Logistics (항만물류분야의 디지털 전환 수용성에 관한 연구)

  • Hyeon-Deok Song;Myung-Hee Chang
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2022.11a
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    • pp.298-299
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    • 2022
  • Digital Transformation in the maritime transportation sector means "by utilizing digital technologies such as artificial intelligence, big data, Internet of Things, block chain, and cloud to create new business models, products, and services for maritime transportation-related companies. It can be defined as a continuous process that adapts to or drives disruptive changes in the market" (Chang, 2021). In a situation where various digital conversion technologies are applied and started to be used in the domestic port logistics field, active acceptance by members can bring about the success of digital conversion. Therefore, in this study, in order to investigate the acceptability of digital transformation in the domestic port logistics sector,

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An Empirical Study on the Factors Affecting the Intention to Use M2E Services

  • Sang Hoon Lee;Min-Ju Kim;Su-Yeon Kim
    • Asia pacific journal of information systems
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    • v.33 no.3
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    • pp.792-811
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    • 2023
  • Recently, Web 3.0 services such as virtual currency, block chain, and NFT are attracting public attention. Users who depended on platforms are moving away from being dependent on service providers and moving to Web 3.0 services. Representative services of Web 3.0 include P2E (Play to Earn) and M2E (Move to Earn). In the case of P2E, various studies have been conducted as it is widely covered in the press and media, but research on M2E is relatively lacking. This study attempts to identify the intention to use M2E by using the expanded technology acceptance model. External factors were selected based on M2E's own characteristics and personal characteristics, a research model was designed, and the proposed hypotheses were verified through factor analysis and goodness of model fit. As a result of the study, it was confirmed that profitability, innovativeness, and self-expression had a positive effect on perceived characteristics, and that perceived usefulness, perceived enjoyment, and social influence had a positive effect on intention to use. Through the research results, practical implications for efficient service operation that meets the needs of users are presented to M2E platform providers.

Effects of Feeding Extruded Soybean, Ground Canola Seed and Whole Cottonseed on Ruminal Fermentation, Performance and Milk Fatty Acid Profile in Early Lactation Dairy Cows

  • Chen, P.;Ji, P.;Li, Shengli
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.2
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    • pp.204-213
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    • 2008
  • Four ruminally cannulated Holstein cows averaging 43 days in milk (DIM) were used in a $4{\times}4$ Latin square to determine the effect of feeding extruded soybean, ground canola seed and whole cottonseed on ruminal fermentation and milk fatty acid profile. One hundred and twenty lactating Holstein cows, 58 (${\pm}31$) DIM, were assigned to four treatments in a completely randomized block design to study the effects of the three types of oilseeds on production parameters and milk fatty acid profile. The four diets were a control diet (CON) and three diets in which 10% extruded soybean (ESB), 5% ground canola seed (GCS) and 10% whole cottonseed (WCS) were included, respectively. Diets consisted of concentrate mix, corn silage and Chinese wild rye and were balanced to similar concentrations of CP, NDF and ADF. Ruminal fermentation results showed that ruminal fermentation parameters, dry matter intake and milk yield were not significantly affected by treatments. However, compared with the control, feeding cows with the three oilseed diets reduced C14:0 and C16:0 and elevated C18:0 and C18:1 concentrations in milk, and feeding ESB increased C18:2 and cis9, trans11 conjugated linoleic acid (CLA). Production results showed that feeding ESB tended to increase actual milk yield (30.85 kg/d vs. 29.29 kg/d) and significantly decreased milk fat percentage (3.53% vs. 4.06%) compared with CON. Milk protein (3.41%) and solid non-fat (13.27%) from cows fed WCS were significantly higher than from cows fed CON (3.24% and 12.63%, respectively). Milk urea N concentrations from cows fed the ESB (164.12 mg/L) and GCS (169.91 mg/L) were higher than cows fed CON (132.31 mg/L). However, intake of DM, 4% fat corrected milk, energy corrected milk, milk fat and protein yields, milk lactose percentage and yield, somatic cell count and body condition score were not affected by different treatments. The proportion of medium-chain fatty acid with 14 to 16 C units in milk was greatly decreased in cows fed ESB, GCS and WCS. Feeding ESB increased the concentration in milk of C18:1, C18:2, C18:3 and cis9, trans11-CLA content by 16.67%, 37.36%, 95.24%, 72.22%, respectively, feeding GCS improved C18:0 and C18:1 by 17.41% and 33.28%, respectively, and feeding WCS increased C18:0 by 31.01% compared with feeding CON. Both ruminal fermentation and production trial results indicated that supplementation of extruded soybean, ground canola seed and whole cottonseed could elevate the desirable poly- and monounsaturated fatty acid and decrease the medium chain fatty acid and saturated fatty acid content of milk fat without negative effects on ruminal fermentation and lactation performance.

The Substates with Mutants That Negatively Charged Aspartate in Position 172 Was Replaced with Positive Charge in Murine Inward Rectifier Potassium Channel (Murine Kir2.1)

  • So, I.;Ashmole, I.;Stanfield, P.R.
    • The Korean Journal of Physiology and Pharmacology
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    • v.7 no.5
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    • pp.267-273
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    • 2003
  • We have investigated the effect on inducing substate(s) of positively charged residues replaced in position 172 of the second transmembrane domain in murine inward rectifier potassium channels, formed by stable or transient transfection of Kir2.1 gene in MEL or CHO cells. Single channel recordings were obtained from either cell-attached patches or inside-out patches excised into solution containing 10 mM EDTA to rule out the effect of $Mg^{2+}$ on the channel gating. The substate(s) could be recorded with all mutants D172H, D172K and D172R. The unitary current-voltage (I-V) relation was not linear with D172H at $pH_i$ 6.3, whereas the unitary I-V relation was linear at $pH_i$ 8.0. The relative occupancy at $S_{LC}$ was increased from 0.018 at $pH_i$ 8.0 to 0.45 at $pH_i$ 5.5. In H-N dimer, that was increased from 0.016 at $pH_i$ 8.0 to 0.23 at $pH_i$ 5.5. The larger the size of the side chain or $pK_a$ with mutants (D172H, D172K and D172R), the more frequent the transitions between the fully open state and substate within an opening. The conductance of the substate also depended upon the pKa or the size of the side chain. The relative occupancy at substate $S_{LC}$ with monomer D172K (0.50) was less than that in K-H dimer (0.83). However, the relative occupancy at substate with D172R (0.79) was similar to that with R-N dimer (0.82). In the contrary to ROMK1, positive charge as well as negative charge in position 172 can induce the substate rather than block the pore in murine Kir2.1. The single channel properties of the mutant, that is, unitary I-V relation, the voltage dependence of the mean open time and relative occupancy of the substates and the increased latency to the first opening, explain the intrinsic gating observed in whole cell recordings.

Inhibitory Effects of Deer Antler Herbal-Acupuncture Solution on Cathepsin S and L Activity in RA Model Mice

  • Ahn, Hyung-Jun;Yoon, Jong-Hwa;Kim, Kyung-Ho;Lee, Seung-Deok;Kim, Kap-Sung
    • Journal of Acupuncture Research
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    • v.22 no.2
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    • pp.71-81
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    • 2005
  • Objective : Dear antler (Cervus korean TEMMINCK var. mantchuricus Swinhoe) used for traditional immunosuppressive and immuno-activating action. The effect of deer antler herbal-acupuncture(DAH) solution, prepared by water extract method, on cathepsin activities in bone tissues (cartilage and synovial) cells from mouse rheumatoid arthritis (RA) model was studied. The cysteine endoprotease cathepsin mediates degradation of the MHC class II invariant chain (Ii) in human and mouse antigen-presenting cells. The studies described here examine the functional significance of cathepsin inhibition on autoantigen presentation and organ-specific autoimmune diseases in a murine model for RA. Methods : An animal model for RA in BALB/c mice thymectomized 3 days after birth (3d-Tx) was constructed All 3d-Tx BALB/c mice developed autoimmune lesions in the bone tissue cells, starting at 3 weeks of age, and the disease mediated by CD4+ T cells was chronic and progressive. Significant inhibitory effects of DAH solution on cathepsin S and L were observed in each organ in a dose-dependent manner. Moreover, we confirmed that cathepsin S and L activity in each organ were clearly inhibited by DAB solution. When we examined the inhibitory effects of DAH solution against autoantigen-specific T cell responses in vitro, in regional lymph node cells, but not in spleens, from model mice, a significant inhibitory effect of DAB solution was observed in a dose-dependent manner. DAH solution do not block T cell proliferation to Con A, indicated that the dose of DAB solution 10 to $20\;{\mu}g/m{\ell}$ was sufficient to inactivate the autoantigen-specific T cell responses in vitro. In vivo therapeutic effects of DAB solution were examined in a murine model for RA, autoantigen-specific (C-II-specific) T cell response were significantly inhibited in LNCs from DAH solution-treated mice. Results : Iinhibition of cathepsin S and L in vivo alters autoantigen presentation and development of organ-specific autoimmunity in RA model. Conclusion : These data identify selective inhibition of cysteine protease cathepsin S and L as a potential therapeutic strategy for autoimmune disease process such RA. Thus, DAH solution will served as a potent anti-inflammatory and anti-arthritic agents for treatment of human RA.

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Synthesis of an Octapeptide (Alanine Angiotensin) (Octapeptide (Alanine Angiotensin) 의 合成)

  • Park, Won-Kil
    • Journal of the Korean Chemical Society
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    • v.5 no.1
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    • pp.33-37
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    • 1961
  • We have shown that carboxy-peptidase destroys the biological activity of angiotensin octa-and deca-peptides. Since Proline occurs as the seventh amino acid from the amino end of the chain and since carboxypeptidase does not cleave proline from a peptid chain, it is evident that the heptapeptid H.asp-arg-val-tyr-ileu-his-pro.OH is formed by this hydrolysis. This peptide must then be biologically inactive. In order to determine whether the phenyl group of the C-terminal amino acid was the necessary requirement for biological activity of the octapeptide, $ala^8$ angiotensin octapeptide(amino acids of peptides numbered from amino end) was synthesized. For this synthesis the four dipeptides were prepared: carbobenzoxy-L-prolyl-L-alanine-P-nitrobenzyl-ester, m.p. $134-135^{\circ}C,$ carbobenzoxy-L-isoleucyl-imidazole benzyl-L-histidine methyl ester, m.p. $114-116^{\circ}C,$ carbobenzoxy-L-valyl-L-tyrosine hydrazide and carbobenzoxy B-benzyl-L-aspartyl-nitro-L-arginine. The first three dipeptides were obtained as crystalline compounds. Imidazole-benzyl-L-histidine was used in the hope that it would block the histidine imidazole against side reactions in steps subsequent to the formation of the C-terminal tetrapeptide. Also, it was through that the imidazole benzylated peptides would be easier to crystallize. This, however, was not the case. The tetrapeptide, carbobenzoxy-L-isoleucyl-L-im, benzyl-histidyl, L-prolyl-L-alanine-nitrobenzyl ester was not obtained in a crystalline form. Neither could the mono-or dihydrobromide of the tetrapeptide free base be induced to crystallize. Carbobenzoxy-L-valyl-L-tyrosine azide was condensed with the tetrapeptide free base to yield the protected hexapeptide; carbobenzoxy-L-valyl-L-tyrosyl-L-isoleucyl-L-im, benzyl, histidyl-L-Prolyl-L-alanine-nitrobenzyl ester. Upon removal of the carbobenzoxy group with hydrogen bromide in acetic acid an amorphous free base hexapeptide ester was obtained. This compound gave the correct C, H, N analysis and contained the six amino acids in the correct ratio. The octapeptide was obtained by condensing this hexapeptide with carbobenzoxy-B-benzyl-L-aspartyl-nitro, L-arginine using the mixed anhydride method of condensation. This amorphous product was proven to be homogenous by chromatography in two solvent systems and upon hydrolysis yielded the eight amino acids in correct ratio. The five protecting groups were removed from the octapeptide by hydrogenolysis over palladium black catalyst. Biological assay of the free peptide indicated that it possessed less than 0.1 per cent of both pressor and oxytocic activity of the phenylalanine8 angiotensin. This suggests that the phenyl group is a point of attachment between angiotensin and its biological receptor site.

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Concept of Seasonality Analysis of Hydrologic Extreme Variables and Design Rainfall Estimation Using Nonstationary Frequency Analysis (극치수문자료의 계절성 분석 개념 및 비정상성 빈도해석을 이용한 확률강수량 해석)

  • Lee, Jeong-Ju;Kwon, Hyun-Han;Hwang, Kyu-Nam
    • Journal of Korea Water Resources Association
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    • v.43 no.8
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    • pp.733-745
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    • 2010
  • Seasonality of hydrologic extreme variable is a significant element from a water resources managemental point of view. It is closely related with various fields such as dam operation, flood control, irrigation water management, and so on. Hydrological frequency analysis conjunction with partial duration series rather than block maxima, offers benefits that include data expansion, analysis of seasonality and occurrence. In this study, nonstationary frequency analysis based on the Bayesian model has been suggested which effectively linked with advantage of POT (peaks over threshold) analysis that contains seasonality information. A selected threshold that the value of upper 98% among the 24 hours duration rainfall was applied to extract POT series at Seoul station, and goodness-fit-test of selected GEV distribution has been examined through graphical representation. Seasonal variation of location and scale parameter ($\mu$ and $\sigma$) of GEV distribution were represented by Fourier series, and the posterior distributions were estimated by Bayesian Markov Chain Monte Carlo simulation. The design rainfall estimated by GEV quantile function and derived posterior distribution for the Fourier coefficients, were illustrated with a wide range of return periods. The nonstationary frequency analysis considering seasonality can reasonably reproduce underlying extreme distribution and simultaneously provide a full annual cycle of the design rainfall as well.

Effect of Supplementation of Allium hookeri on Growth Performance and Intestinal Health for Broiler Chickens (육계 사료 내 삼채(Allium hookeri) 첨가에 따른 사양성적 및 장 건강 지표 변화)

  • Chae Won Lee;June Hyeok Yoon;Su Hyun An;In Ho Cho;Changsu Kong
    • Korean Journal of Poultry Science
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    • v.50 no.3
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    • pp.161-169
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    • 2023
  • The present study aimed to investigate the effect of Allium hookeri (AH) root on growth performance, serum antioxidant enzyme activity, cecal short-chain fatty acid profiles, and tight junction-related gene expression of broiler chickens. On day 10, 96 birds were allocated to one of two dietary treatments with 6 replicate cages, and 8 birds per cage in a randomized complete block design. The experimental diets consisted of a corn-soybean meal-based control diet and a diet supplemented with 0.3% AH root powder at the expense of the corn in the control diet. The experimental diets were formulated to meet or exceed the nutrients requirements of broilers recommended by Aviagen for each phase (from day 10 to 21 and from day 21 to 28). On day 28, a bird representing the median body weight in each cage was selected, and then blood, cecal digesta, and jejunum tissue samples were collected. No significant differences were observed in body weight gain and feed intake among dietary treatments. However, birds fed the diet containing AH showed a greater gain-to-feed ratio compared to the control group at 21 days of age and throughout the entire experimental period (P<0.05). Serum antioxidant enzyme activity, cecal short-chain fatty acid profiles, and tight junction-related gene expression were not affected by the dietary AH supplementation. Based on the results of the present study, dietary AH supplementation may improve the gain-to-feed ratio, but not gut health markers in broiler chickens from day 10 to 28.

Intensified Low-Temperature Fischer-Tropsch Synthesis Using Microchannel Reactor Block : A Computational Fluid Dynamics Simulation Study (마이크로채널 반응기를 이용한 강화된 저온 피셔-트롭쉬 합성반응의 전산유체역학적 해석)

  • Kshetrimatum, Krishnadash S.;Na, Jonggeol;Park, Seongho;Jung, Ikhwan;Lee, Yongkyu;Han, Chonghun
    • Journal of the Korean Institute of Gas
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    • v.21 no.4
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    • pp.92-102
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    • 2017
  • Fischer-Tropsch synthesis reaction converts syngas (mixture of CO and H2) to valuable hydrocarbon products. Simulation of low temperature Fischer -Tropsch Synthesis reaction and heat transfer at intensified process condition using catalyst filled single and multichannel microchannel reactor is considered. Single channel model simulation indicated potential for process intensification (higher GHSV of $30000hr^{-1}$ in presence of theoretical Cobalt based super-active catalyst) while still achieving CO conversion greater than ~65% and $C_{5+}$ selectivity greater than ~74%. Conjugate heat transfer simulation with multichannel reactor block models considering three different combinations of reactor configuration and coolant type predicted ${\Delta}T_{max}$ equal to 23 K for cross-flow configuration with wall boiling coolant, 15 K for co-current flow configuration with subcooled coolant, and 13 K for co-current flow configuration with wall boiling coolant. In the range of temperature maintained (498 - 521 K), chain growth probability calculated is desirable for low-temperature Fisher-Tropsch Synthesis.