This study seeks to explore how key restaurant attributes differently influence customer satisfaction and dissatisfaction across pre-pandemic and post-pandemic periods, as well as across various economic segments. By employing impact asymmetry analysis (IAA), the research identifies the primary drivers of customer satisfaction and dissatisfaction, examining their uneven on customer satisfaction in Korean restaurants. The findings underscore the non-linear and asymmetric nature of customer responses to various service attributes, highlighting the significant influence of economic factors and the pandemic on dining expectations and experiences. This research deepens our understanding of the factors shaping customer satisfaction dynamics, particularly in the context of the evolving post-pandemic restaurant industry.

This study examined consumer perceptions and market trends of Korean food products sold on Amazon, focusing on keyword and review analysis. As Korean cuisine gains global attention, particularly in the U.S., it is essential to understand how international consumers perceive these products. Data were collected from Amazon, encompassing product details and customer reviews of Korean food categories. Frequently mentioned keywords in the reviews were identified, and customer sentiments were explored using Python-based data analysis. The results suggest that taste, especially spiciness and sweetness, is a key determinant of consumer satisfaction. Although Korean food was generally well-received, packaging and delivery issues were common complaints. These findings provide strategic insights for Korean food manufacturers aiming to expand globally, emphasizing the need for tailored product development and enhanced logistics.

The inclusion of conductive carbon materials into lithium-ion batteries (LIBs) is essential for constructing an electrical network of electrodes. Considering the demand for cells in electric vehicles (e.g., higher energy density and lower cell cost), the replacement of the currently used carbon black with carbon nanotubes (CNTs) seems inevitable. This review discusses how CNTs can contribute to the development of advanced LIBs for EVs. First, the reason for choosing CNTs as a conducting agent for the cathode is discussed in terms of energy density. Second, the reinforcing effect of CNTs on the anode is described with respect to the choice of silicon as the active material. Third, the development of water-based cathode fabrication as well as dry electrode fabrication with aid of CNTs is discussed. Fourth, three technical hurdles, that is, the price, dispersion issue, and entrapped metal impurities, for widespread use of CNTs in LIBs are discussed.

We demonstrated the sensitivity of optically active single-walled carbon nanotubes (SWCNTs) with a diameter below 1 nm that were homogeneously dispersed in cement composites under a mechanical load. Deoxyribonucleic acid (DNA) was selected as the dispersing agent to achieve a homogeneous dispersion of SWCNTs in an aqueous solution, and the dispersion state of the SWCNTs were characterized using various optical tools. It was found that the addition of a large amount of DNA prohibited the structural evolution of calcium hydroxide and calcium silicate hydrate. Based on the in-situ Raman and X-ray diffraction studies, it was evident that hydrophilic functional groups within the DNA strongly retarded the hydration reaction. The optimum amount of DNA with respect to the cement was found to be 0.05 wt%. The strong Raman signals coming from the SWCNTs entrapped in the cement composites enabled us to understand their dispersion state within the cement as well as their interfacial interaction. The G and G’ bands of the SWCNTs sensitively varied under mechanical compression. Our results indicate that an extremely small amount of SWCNTs can be used as an optical strain sensor if they are homogeneously dispersed within cement composites.

Field sequential 액정 디스플레이(FSLCD)는 컬러필터를 사용하지 않아 높은 투과율 특성을 보이고 광 원으로 LED를 사용함으로써 색재현성이 매우 우수하다. 하지만 FSLCD(60Hz 구동)를 실현하기 위해서는 액정의 응답속도가 5ms이하로 고속응답 특성을 보여야 한다. 따라서 본 논문에서는 고속응답 ECB(electrically controlled birefringence) 셀의 최적 구조를 연구하여 5ms 이하의 응답시간을 얻었다. 그리고 ECB 모드에서 높은 구동전압과 시야각을 개선하기 위해 필름 보상을 연구하였다. 판상형 액정필름(discotic film)과 TAC(triacetyl cellulose) 필름의 위상차 값을 최적화함으로써 구동전압을 5V로 낮추고 상하좌우에서 160° 이상(CR>10:1)의 시야각을 실현하였다.

BACKGROUND Ca2+ oscillations during fertilization induce eggs activation and embryonic development in mammalian eggs.. The type 1 inositol 1,4,5-trisphosphate receptor (IP3R1) is in charge of Ca2+ oscillations for the release of stored Ca2+ from the endoplasmic reticulum. The capacity of this oscillation is obtained during egg maturation and corresponds with an increase in the sensitivity of the IP3R1 and their localization in cytoplasm. Cluster formation of IP3R1 in the egg cortex is important to initiation of Ca2+ oscillations during egg and sperm fusion. In this study, we investigated that cell cycle–coupled redistribution of IP3R1 and Ca2+- oscillatory activity in mouse zygotes. MATERIALS AND METHODS Metaphase II arrested eggs were collected from ICR female mouse after super ovulation induction. At 14 hr post hCG, MII eggs were collected, and artificially activated in Ca2+ free CZB medium with 10 mM SrCl2 for 2 hrs. Pronuclear zygotes (PN) were collected from Strontium activated eggs at 8 hr post activation, and the first mitotic eggs were collected at 16~17 hr post activation. To identify cell cycle coupled IP3R1 redistribution, MII eggs, zygotes, and first mitotic eggs were collected, and fixed for immunostaining with anti-IP3R1antibody (CT-1) and observed on CLSM. Ca2+-oscillatory activity was monitored with fluorescence microscope mounted SimplePCI program (Hamamatsu) after injection of cRNA of mouse phospholipase C zeta (mPLCZ). RESULT IP3R1 were shown clusters, 1~2 um in diameter, in cortex of ovulated MII eggs with high Ca2+ oscillatory activity by mPLCZ injection. These eggs represent more than 6 spikes per 60 min. However, IP3R1 clusters were disappeared in PN eggs and these eggs showed very low Ca2+- oscillatory activity by mPLCZ. In mitosis I stage eggs, clusters of IP3R1 were appeared and Ca2+-oscillatory activity was reactivated slightly (2 spikes per 60 min). CONCLUSIOINS This study introduced the redistribution of IP3R1 clusters were occurred in egg activation according to cell cycle dependent manner. Also, functional modification of IP3R1 including protein phosphorylation was associated with cortical clustering of IP3R1 in cell cycle coupled Ca2+ oscillatory activity.