The Metaverse’s virtual world is used in various industries and is expected to continue to grow in the future. In addition, the Metaverse is a new type of society that integrates various new technologies, and NFT products play an essential role. Therefore, NFT product characteristics and industry trends should be assessed to revitalize the NFT market. To this end, this study confirms the influence relationship between social presence and NFT product characteristics in the Metaverse environment and examines the impact of each characteristic on consumer satisfaction and continued engagement intention to NFT product. Statistical analysis such as exploratory factor analysis, reliability analysis, confirmatory factor analysis, correlation analysis, and structural equation modeling (SEM) using IBM SPSS Amos was conducted on data collected through a survey targeting male and female Korean consumers in their age group 10 to 50. Study results indicate that social presence significantly impacted all characteristics of NFT products (authenticity, scarcity, rarity, collectability, and interactivity). Scarcity and authenticity significantly impacted consumer satisfaction, and both authenticity and consumer satisfaction significantly impacted continued engagement intention. Thus, effective product development and marketing strategies can be established only by presenting different emphasized characteristics depending on the type of NFT product and the Metaverse’s social presence.

본 연구팀은 피아노제조산업에서 대표적인 기업인 ㈜야마하가 국제화 과정에서 제품 전략과 시장 전략을 동시에 적용하는 사례를 통해서 국제경영에 관한 새로운 모델인 국제경영의 4가지 본원적 메커니즘(4 Generic Mechanisms in Global Management: 4GMGM)의 현실적용가능성을 다루었다. 야마하 피아노가 초기에 현으로 소리를 내는 전통적인 건반악기인 피아노를 일본이라는 현지 시장에서 개발 판매하는 현지화(Localization) 전략에서 출발했다가, 디지털 피아노를 개발 하면서 현세화(Loc-balization) 전략으로 나아갔고, 최상위 품질을 갖춘 그랜드피아노를 개발하 면서 세계화(Globalization) 전략의 정점을 찍었다가, 현지 음악 소리를 내는 맞춤형 피아노를 일 렉트릭 파이노의 한 영역으로 개발하면서 세현화(Glocalization) 전략으로 변신한 과정을 검토했 다. 이 연구를 통해 기업이 국제화하는 과정에서 제품전략과 시장전략을 동시에 개발해야 한다는 논리를 제시한 4GMGM이 현실을 설명하는데 적절하다는 검토 의견을 도출했다.

Distribution and logistics industries contribute some of the biggest GDP(gross domestic product) in South Korea and the number of related companies are quarter of the total number of industries in the country. The number of retail tech companies are quickly increased due to the acceleration of the online and untact shopping trend. Furthermore, major distribution and logistics companies try to achieve integrated data management with the fulfillment process. In contrast, small and medium distribution companies still lack of the capacity and ability to develop digital innovation and smartization. Therefore, in this paper, a deep learning-based demand forecasting & recommendation model is proposed to improve business competitiveness. The proposed model is developed based on real sales transaction data to predict future demand for each product. The proposed model consists of six deep learning models, which are MLP(multi-layers perception), CNN(convolution neural network), RNN(recurrent neural network), LSTM(long short term memory), Conv1D-BiLSTM(convolution-long short term memory) for demand forecasting and collaborative filtering for the recommendation. Each model provides the best prediction result for each product and recommendation model can recommend best sales product among companies own sales list as well as competitor’s item list. The proposed demand forecasting model is expected to improve the competitiveness of the small and medium-sized distribution and logistics industry.

In the event of an emergency such as facility shutdown during process operation, the by-product gas must be urgently discharged to the vent stack to prevent leakage, fire, and explosion. At this time, the explosion drop value of the released by-product gas is calculated using ISO 10156 formula, which is 27.7 vol%. Therefore, it does not correspond to flammable gas because it is less than 13% of the explosion drop value, which is the standard for flammable gas defined by the Occupational Safety and Health Act, and since the explosion drop value is high, it can be seen that the risk of fire explosion is low even if it is discharged urgently with the vent stock. As a result of calculating the range of explosion hazard sites for hydrogen gas discharged to the Bent Stack according to KS C IEC 60079-10-1, 23 meters were calculated. Since hydrogen is lighter than air, electromechanical devices should not be installed within 23 meters of the upper portion of the Bent Stack, and if it is not possible, an explosion-proof electromechanical device suitable for type 1 of dangerous place should be installed. In addition, the height of the stack should be at least 5 meters so that the diffusion of by-product gas is facilitated in case of emergency discharge, and it should be installed so that there are no obstacles around it.

The aim of this study was to prepare rice straw silage using cabbage by-product and persimmon peel which are agricultural by-products produced during the same season in Korea. The treatments comprised a commercial corn silage as the control and four rice straw silages (P15-1, P15-2, P30-1, and P30-2) with different levels of persimmon peel supplementation (15%, 30%) and ensiled periods (1 or 2 months). The cabbage by-products were used to adjust silage moisture (approximately 65%). The quality of the experimental silages was evaluated based on organic acid content, palatability to three Holstein dairy cows, and manufacturing cost. In the corn silage, all chemical compositions, except total digestible nutrients and levels of lactic and butyric acids, were significantly (p<0.05) higher than those of the rice straw silages. However, considering the quality analysis using Flieg's score, the rice straw silage supplemented with 30% persimmon peel ensiled for 2 months (P30-2) was estimated as second grade to corn silage, and was relatively better in palatability to dairy cows than the other rice straw silages, which were considered third grade. The manufacturing cost of rice straw silages using cabbage by-product and persimmon peel compared to that of corn silage was reduced by 28%. Consequently, to prepare rice straw silage adjusted to 65% moisture using only cabbage by-products without inoculant, 30% of persimmon peel, 10% of ground corn, and 2% of molasses as a sugar source should be ensiled for at least 2 months.

Molten Salt Reactor, which employs molten salt mixture as fuel, has many advantages in reactor size and operation compared to conventional nuclear reactor. In developing Molten Salt Reactor, the behavior of fission product in operation should be preliminary evaluated for the correct design of reactor and its associated system including off-gas treatment. In this study, for 100 Mw 46 KCl- 54 UCl3 based Molten Salt Reactor with operating life time of 20 year, the fission product behavior was estimated by thermodynamic modeling employing FactSage 8.2. Total inventory of all fission product were firstly calculated using OpenMC code allowing depletion during neutronic calculation. Then, among all inventory, 46 element species from Uranium to Holmium were chosen and given to the input for equilibrium module of Factsage with its mass. In phase equilibrium calculation, for the correct description of solution phase, KCl-UCl3 solution database based on modified quasichemical model in the quadruplet approximation (ANL/CFCT-21/04) was employed and the coexisting solid phase was assumed to pure state. With the assumption of no oxygen and moisture ingress into reactor system, equilibrium calculation showed that 1% of solid phase and of gas phase were newly formed and, in gas phase, major species were identified : ZrCl4 (47%), Xe (33%), UCl4 (14%), Kr (5%), Ar (1%) and others. This result reveals that off-gas treatment of system should account for the appropriate treatment of ZrCl4 and UCl4 besides treatment of noble gas such as Xe and Kr.

Radiation from spent nuclear fuel (SNF) is one of key factors affecting the dissolution process of SNF and the source term from repository. The dissolution rate of uranium dioxide (UO2) matrix of SNF is expected to control the release of radionuclides from SNF in contact with water under geological disposal conditions. Based on the oxidative dissolution mechanism, the solubility of UO2 can increase significantly if the reducing environment near the fuel surface is altered by water radiolysis caused by radiation from SNF. Therefore, the analysis of water radiolysis products such as radicals (·OH, ·OH2, eaq, ·H) and molecules (H3O+, H2, H2O2) is perquisite for studies on the rate of such dissolution process to determine oxidation/dissolution mechanism and related rate constants. In this study we examined the two-known spectroscopic methods developed for H2O2 determination; one is the luminol-based chemiluminescence (luminol-CL) method and the other is the spectrophotometry using ferrous oxidation-xylenol orange complexation (FOX). Their applicability for quantitative analysis of H2O2 in potential aqueous samples from SNF dissolution studies was evaluated in terms of the analytical dynamic range (ADR), the limit of detection (LOD) and the interfering effects of various metal ions possibly present in real samples. The luminol-CL method exploits the chemiluminescence reaction caused by luminol; when in the presence of a metallic catalyst (e.g., Cu2+, Co2+), luminol emits a blue light (425 nm) at pH 10- 11 in response to oxidizing agents such as hydrogen peroxide. Although a flow-through reaction system is routinely employed to enhance the analytical sensitivity we achieved the ADR up to ~200 μM and LOD < 1 μM by a batch-wise CL detection using conventional cuvette cells and an intensified charge-coupled device (ICCD). Interestingly, it turned out that the interfering effects of other metal ions (e.g., UO2 2+, U4+, Fe2+ and Fe3+) is minimal, which should be advantageous for the luminol-CL method to be employed for samples potentially containing other metal ions. On the other hand, the FOX method spectrophotometrically analyzes H2O2 based on the difference in color (or absorption spectra) of Fe-xylenol orange (XO) complexes. Initially, the Fe2+-XO complex was provided in working solutions at pH 3, which was subsequently mixed with samples having H2O2 and allowed for quantitative oxidation of Fe2+ to Fe3+. Typically, by monitoring the absorbance of Fe3+-XO complex at 560-580 nm (λmax) the ADR up to ~100 μM and LOD ~1.6 μM were achieved. However, it is found that interfering effects from M3+ and M4+ ions are significant; these interfering metal ions can form XO complexes so as to directly contribute the measured absorbance. In contrast, the influence from M2+ ions was found to be negligible. To summarize we conclude that both methods can be applied for H2O2 determination for aqueous samples taken from SNF dissolution tests. However, prior to applying the FOX method the metal ion composition in those samples should be thoroughly identified not to overestimate the H2O2 concentration of samples. More details of underlying chemical reactions in both methods will be discussed in the presentation.

Nuclear power plants in Korea stores approximately 3,800 drums of paraffin solidification products. Due to the lack of homogeneity, these solidification products are not allowed to be disposed of. There is therefore a need for the separation of paraffin from the solidification products. This work developed an equipment for a selective separation of paraffin from the solidification product using the vacuum evaporation and condensational recovery method in a closed system. The equipment mainly consists of a vacuum evaporator and a condensational deposition recovery chamber. Nonisothermal vacuum TGAs, kinetic analyses and kinetic predictions were conducted to set appropriate operation conditions. Its basic operability under the established conditions was first confirmed using pure paraffin solid. Simulated paraffin solidification product fixing dried boric acid waste including nonradioactive Co and Cs were then fabricated and tested for the capability of selective separation of paraffin from the simulated waste. Paraffin was selectively separated without entertainment of Co and Cs. It was confirmed that the developed equipment could separate and recover paraffin in the form of nonradioactive waste.