미디어아트 제작방식중 하나인 미디어 파사드는 화려한 이미지와 색상, 영상표현 기법으로 관람객의 시각적 몰입을 강화하고 호응을 이끈다. 하지만 시각적 이미지 표현에만 집중하는 경우, 제작자가 의도한 메시지나 의미가 관람객에게 전달되기 어려울 수 있으며, 미디어파사드 의 기대효과도 낮아지는 한계점이 있다. 본 연구는 미디어파사드 콘텐츠인 <보물선을 깨우다, 아시아 해양실크로드> 제작 및 전시사례를 통해 전시구성, 서사구조, 시청각적 요소를 분석하 였으며, 이미지 재현과 스토리텔링을 연구하였다. 이를 통해 미디어파사드를 효과적으로 전시 하기 위해서는 선형적 이미지 제시가 아닌 서사구조의 시각이미지가 필요하며, 연속성과 반복 성이 수반되어야 한다는 점, 또 은유와 상징으로 스토리를 재구성하는 방식이 필요하다는 것 을 확인하였다. 향후 이러한 개발방향을 고려한 미디어파사드는 관람객에게 더욱 풍부한 문화 향유 기회를 제공하고 제작자가 의도한 메시지와 의미를 더욱 효과적으로 전달할 수 있을 것 이다.

Safe radiation management is essential not only for operational nuclear power plants but also for nuclear plants to be decommissioned. When spent nuclear fuel is present on-site, meticulous radiation emergency plans are necessary to ensure safety. In Korea, numerous radiation emergency plans have been established for operational nuclear reactors. These plans delineate distinct response mitigation measures for white, blue, and red emergencies. However, clear regulations are yet to be devised for radiation emergency plans for reactors to be decommission. Therefore, this study investigated the decommissioning plan and status of Kori unit 1 to comprehensively analyze the current status of decommissioning safety in Korea. In this study, radiation emergency plans of decommissioning nuclear power plants abroad were reviewed to confirm radiation emergency action levels. Furthermore, radioactive waste treatment facilities, to be used for decommissioning reactors in Korea were evaluated. Moreover, the study assessed emergency plans (especially, emergency initiating conditions) for operational nuclear power plants in Korea for potential use in the decommissioning phase. This study proposed an emergency initiating condition that can be used for decommissioning reactors in Korea. Considering the anticipated introduction of plasma torch melting facility in Korea, this study examined the conditions of radiation emergency plans can be altered. This study identified effective measures and guidelines for managing radiological emergency initiating conditions, and effective decommissioning of nuclear power plants in Korea.

최근에 생성형 인공지능 활용에 관한 많은 연구가 진행되고 있다. Generative AI 도구와 플랫 폼 수량이 증가하고 있는 추세에 따라, Generative AI 도구는 텍스트와 이미지, 소리, 비디오, 그리고 3D 모델을 생성하는 기능을 가지고 있을 뿐만 아니라 프롬프트만으로도 아이디어와 콘텐츠를 포함하여 복잡한 작품을 생성할 수 있다. 본 연구는 Generative AI 도구와 플랫폼이 디지털 아트 전공학생들에게 미치는 영향을 탐구 하였으며, 특히 창작 과정에 그들의 역할과 작품에 미치는 영향을 구체적으로 살펴보았다. 또한, 본 연구는 Generative AI 작품에 의해 디지털 아트 전공 학생들에게 필요한 기술이나 특징에 대한 질적 연구법 중의 주체 분석 방법으로 자세히 연구하였다.

In this study, we investigated the suppression of the corrosion of cast iron in a copper–cast iron double-layered canister under local corrosion of the copper layer. The cold spray coating technique was used to insert metals with lower galvanic activity than that of copper, such as silver, nickel, and titanium, between the copper and cast iron layers. Electrochemically accelerated corrosion tests were performed on the galvanic specimens in KURT groundwater at a voltage of 1.0 V for a week. The results revealed that copper corrosion was evident in all galvanic specimens of Cu–Ag, Cu–Ni, and Cu–Ti. By contrast, the copper was barely corroded in the Cu–Fe specimens. Therefore, it was concluded that if an inactive galvanic metal is applied to the areas where local corrosion is concerned, such as welding parts, the disposal canister can overcome local or non-uniform corrosion of the copper canister for long periods.

Silage inoculants, crucial in modern silage production, comprise beneficial microorganisms, primarily lactic acid bacteria (LAB), strategically applied to forage material during ensiling. This study aimed to compare the effectiveness of various inoculants produced by different companies. Five treatments were evaluated, including a control group: T1 (Lactobacillus plantarum), T2 (Lactobacillus plantarum + Pediococcus pentosaceus), T3 (Lactobacillus plantarum + Pediococcus pentosaceus + Lactobacillus buchneri), T4 (Lactobacillus plantarum + Lactobacillus acidophilus + Lactobacillus bulgaricus), and T5 (Lactobacillus plantarum + Pediococcus pentosaceus + Enterococcus faecium). Italian ryegrass was harvested at the heading stage and treated with these silage inoculants. Samples were collected over a 60-day ensiling period. Co-inoculation with L. plantarum and P. pentosaceus (T2) resulted in significantly higher CP compared to the control group co-inoculation exhibited with resulted in Lactobacillus plantarum and Pediococcus pentosaceus in the T2 treatment exhibited higher CP content of 106.35 g/kg dry matter (DM). The T3 treatment, which included heterofermentative bacterial strains such as Lactobacillus buchneri, exhibited an increase in acetic acid concentration (11.15 g/kg DM). In the T4 treatment group, which utilized a mixed culture of Lactobacillus acidophilus and Lactobacillus bulgaricus, the NH3-N/TN content was observed to be the lowest (20.52 g/kg DM). The T5 containing Enterococcus faecium had the highest RFV (123) after 60 days. Expanding upon these findings, the study underscores not only the beneficial effects of particular inoculant treatments on silage quality but also underscores the potential of customized inoculation strategies in maximizing nutrient retention and overall silage preservation.

본 연구는 민간시장의 절화 유통 현황을 조사하여 국내 절 화 시장 유통 및 판매의 기초 자료로 제공하고자 수행하였다. 조사 기간은 2022년 5월부터 10월까지이며, 민간시장 내 판 매 점포 수, 취급 품목, 수입국 및 품목 등을 비교 및 분석하 였다. 민간시장은 서울 서초구 반포동에 위치한 강남터미널 꽃시장을 대상으로 판매 품목 및 수입 국가 등을 조사하였고, 비교 대상인 공영시장의 경우 한국농수산식품유통공사 화훼 유통정보에서 제공되는 양재동 화훼공판장 거래 품목을 조사 하였다. 조사 결과, 민간시장의 월별 절화 판매 점포 수는 평 균 143개였다. 민간시장에서는 5월을 제외하고 장미 판매 매 장이 가장 많았다. 5월에는 카네이션 판매 매장이 가장 많았 으며 장미, 리시안셔스, 거베라가 그 뒤를 이었다. 민간시장 점포 내 수입 품목의 원산지는 호주, 중국, 콜롬비아, 이스라 엘, 이탈리아, 일본, 네덜란드, 페루, 남아프리카 공화국, 미 국, 베트남 등으로 조사되었다. 취급 품목은 민간시장이 69개 로 공영시장 18개에 비해 약 3.8배 많았으며, 이는 민간시장에서 수입 절화가 더 많이 유통되고 있음을 시사한다. 민간시 장은 공영시장과 달리 유통 정보를 알 수 있는 시스템이 없어 소비자들이 제품의 원산지, 품질, 가격 등을 파악하기 어렵다. 따라서, 민간시장의 절화 유통 정보를 소비자들에게 정확히 제공할 필요가 있으며, 이를 통한 투명한 거래 제공 및 소비자 의 신뢰도를 높이는 것이 중요하다.

Despite advancements in therapeutic approaches, radiotherapy and cisplatin-based chemotherapy remain primary noninvasive treatments for patients with oral squamous cell carcinoma (OSCC). Moreover, the 5-year survival rate for patients with OSCC has remained almost unchanged for several decades, and many side effects of chemotherapy still exist. In this study, three-dimensional (3D) models of OSCC were established using fibroblasts, and the efficacy of various biological inhibitors was evaluated. A culture of epithelial cells with two types of fibroblasts (hTERT-hNOFs and cancer-associated fibroblasts) within a type I collagen matrix resulted in the formation of a continuous layer of tightly packed cells compared to models without fibroblasts. Furthermore, the effects of biological chemicals, including Y27632, latrunculin A, and verteporfin, on these models were investigated. The stratified formation of the epithelial layer and invasion in OSCC 3D-culture models were effectively inhibited by verteporfin, whereas invasion was weakly inhibited by Y27632 and latrunculin. Collectively, the developed OSCC 3D-culture models established with fibroblasts demonstrated the potential for drug screening, with verteporfin showing promising efficacy.

목적 : 본 연구는 8세에서 19세의 근시 학생을 대상으로 어린이 근시관리 누진 안경렌즈의 착용실태를 조사하고 착용 후 2년간 근시도의 변화를 확인하고자 하였다. 방법 : 2019년 6월부터 2023년 5월까지 수원 G 안경원에서 어린이 근시관리 누진렌즈를 구매한 110명을 대상 으로 근시 진행완화를 위해 렌즈의 착용을 지속하고 있는지 그리고 중도 포기했다면 그 이유를 조사하였다. 그 후 2차 정기방문으로 안경을 다시 교정받은 기록이 있는 72명을 대상으로 초점렌즈(A그룹, 33명)와 어린이 근시관리 누진렌즈(B그룹, 39명)를 착용한 두 그룹으로 나누어 2년간 추적 조사하였다. 결과 : 어린이 근시관리 누진렌즈를 처방받은 110명의 1차 대상자 중 15명(13.6%)이 근시진행 완화 안경 착용 을 중도 포기했으며 이들 중 남자는 11명(73.3%), 여자는 4명(26.6%) 이었다. 또한, 중도 포기한 이유로는 구매의 편의성과 비용문제가 주된 이유로 조사되었다. 1차, 2차, 3차 방문 시기에 평균 등가구면 굴절력은 A그룹에서는 – 2.09±1.43, –2.78±1.52, –3.31±1.55 D이었고, B그룹은 –2.04±1.08, –2.63±1.06, -2.94±1.08 D로 측정되 었다. 각각의 안경을 2년간 착용한 후에 평균 등가구면 굴절력의 변화량은 A그룹에서 –1.22±0.56 D이었고, B그 룹에서는 –0.90±0.51 D를 보였다(p=0.010). 결론 : 8세에서 19세의 근시가 있는 초중고 학생은 2년 간 어린이 근시관리 누진렌즈를 착용한 후에 단초점렌즈 를 착용한 그룹에 비해 근시 진행이 지연되었다. 근시관리 안경렌즈의 성공적인 시장 정착을 위해서는 더욱 다양한 모집단을 장기 추적 관찰하여 그 효과를 연구한 자료가 필요하다고 생각된다.

The bentonite buffer material is a crucial component in an engineered barrier system used for the disposal of high-level radioactive waste. Because a large amount of heat from the disposal canister is released into the bentonite buffer material, the thermal conductivity of the bentonite buffer is a crucial parameter that determines the design temperature. At the Korea Atomic Energy Research Institute (KAERI), a new standard bentonite (Bentonil-WRK) has been used since 2022 because Gyeongju (KJ) bentonite is no longer produced. However, the currently available data are insufficient, making it essential to investigate both the basic and complex properties of Bentonil-WRK. Thus, this study evaluated its geotechnical and thermal properties and developed a thermal conductivity empirical model that considers its dry density, water content, and temperature variations from room temperature to 90°C. The coefficient of determination (R2) for the model was found to be 0.986. The thermal conductivity values of Bentonil-WRK were 1–10% lower than those of KJ bentonite and 10–40% higher than those of MX-80 bentonites, which were attributable to mineral-composition differences. The thermal conductivity of Bentonil-WRK ranged between 0.504 and 1.149 W·(m−1·K−1), while the specific heat capacity varied from 0.826 to 1.138 (kJ·(kg−1·K−1)).

Since rice is the main food in Korea, there are no regulations on corn milling yet. Corn is known as one of the world's top three food crops along with wheat and rice, and it is known that 3.5 billion people worldwide use corn for food. In addition, corn mills are not developed or sold in Korea, but the use of corn mills is increasing significantly in many countries in Southeast Asia. In the Philippines, as Korea's rice mill import increases, Korea's KAMICO (Korea Agricultural Machinery Industry Cooperative) and domestic company A agreed to develop a corn mill jointly with PHilMech, an organization affiliated with the Philippine Ministry of Agriculture. However, research on corn milling was very insignificant, so the development was carried out based on the technology of Korea's rice mill. Rice milling is performed by peeling off the skin of rice and producing brown or white rice, so it is carried out by removing the skin and cutting the skin. On the other hand, in the corn mill, the skin of the corn is peeled, pulverized and selected to produce main products suitable for edible use. Therefore, in order to develop a corn mill, processes such as peeling, transfer, grinding, sorting, and by-product separation are required, and suitable parts must be developed. In addition, the performance must be gradually improved through experiments in which corn is repeatedly milled. The Philippines produces 7.98 million tons/year of corn, which is about 100 times that of Korea, and is mostly consumed as a staple food. This is about 10% of the total crop production in the Philippines. In addition, the main cultivation complexes of corn are the mountainous regions of Tarlac or Pangasinan, and the produced corn is 72.4% of the so-called yellow corn called Arabel and Sarangani, and the remaining 27.6% are known as white corn. In this study, it was intended to produce grains of 2.5 mm or less suitable for food for yellow corn and to develop a corn mill for 200 kg per hour. Detailed conditions for development are stipulated as more than 55% of the main product recovery rate, more than 31% of the by-product recovery rate, less than 5% of the raw material loss rate, and more than 80% of the embryo dislocation rate. In this study, to achieve this, the overall process of the corn mill was developed, and the optimal conditions for the corn mill were obtained through the development of parts and empirical tests to improve performance. In addition, it was intended to achieve the development goal by evaluating and analyzing the performance of each part so that it did not conflict.

본 논문은 회분식 반응기에서 습식 산화법으로 합성한 칼륨 페레이트(VI)에 의한 난분해성 아조 염료Reactive Black 5의 분해 과정을 연구하는 것을 목적으로 한다. 수용액에서 RB5의 분해는 pH, Ferrate (VI) 투입량, 초기 농도, 수용액 온도 등 다양한 변수의 조건에서 연구되었다. RB5 경우에는 최대 분해 효율은 pH 7.0에서 63.2%가 달성되었으며, 이 실험 조건에서 얻은 kapp 값은 190.49 M-1s-1 으로 나타났다. 온도 또한 가장 중요한 매개 변수 중 하나로 연구되었으며, 그 결과로부터 온도(45°C까지)를 증가시키면 페레이트(VI)에 의한 아조 화합물 염료의 분해 효율이 증가하고, 온도가 45°C를 초과하면 분해 효율이 저하되는 것으로 나타났다.

The Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer (SPHEREx) will provide all-sky spectral survey data covering optical to mid-infrared wavelengths with a spatial resolution of 6.′′2, which can be widely used to study galaxy formation and evolution. We investigate the galaxy-galaxy blending in SPHEREx datasets using the mock galaxy catalogs generated from cosmological simulations and observational data. Only ∼0.7% of the galaxies will be blended with other galaxies in all-sky survey data with a limiting magnitude of 19 AB mag. However, the fraction of blended galaxies dramatically increases to ∼7–9% in the deep survey area around the ecliptic poles, where the depth reaches ∼22 AB mag. We examine the impact of the blending in the number count and luminosity function analyses using the SPHEREx data. We find that the number count can be overestimated by up to 10–20% in the deep regions due to the flux boosting, suggesting that the impact of galaxy-galaxy blending on the number count is moderate. However, galaxy-galaxy blending can marginally change the luminosity function by up to 50% over a wide range of redshifts. As we only employ the magnitude limit at Ks-band for the source detection, the blending fractions determined in this study should be regarded as lower limits.

A force-free field (FFF) is determined solely by the normal components of magnetic field and current density on the entire boundary of the domain. Methods employing three components of magnetic field suffer from overspecification of boundary conditions and/or a nonzero divergence-B problem. A vector potential formulation eliminates the latter issue, but introduces difficulties in imposing the normal component of current density at the boundary. This paper proposes four different boundary treatment methods within the vector potential formulation. We conduct a comparative analysis of the vector potential FFF solvers that we have developed incorporating these methods against other FFF codes in different magnetic field representations. Although the vector potential solvers with the new boundary treatments do not outperform our poloidal-toroidal formulation code, they demonstrate comparable or superior performance compared to the optimization code in SolarSoftWare. The methods developed here are expected to be readily applied not only to force-free field computations but also to time-dependent data-driven simulations.

해사영어는 선박 운항, 해양 안전, 선내 의사소통 및 선외 교신을 위해 설계된 특수한 영어 언어체계이다. 국제해사기구 STCW(선원의 훈련, 자격증명 및 당직근무의 기준에 관한 국제협약)에 따르면 국제항해에 종사하는 항해사가 되기 위해서는 SMCP를 포함한 해사영어 대한 충분한 이해가 수반되어야 한다. 본 연구는 음성인식, 번역, 단어 기입 등 유형의 해사영어시험을 통하여 학생들 의 해사영어 활용 능력을 측정하고 플랫폼 사용에 따른 시험 점수 향상 정도, 나아가 초임항해사로 나가기 위하여 요구되는 해사영어 시험 플랫폼 활용 시간 등을 조사하고자 하였다. 실험은 먼저 초기 시험을 통해 학생들의 일반영어능력과 SMCP 활용 능력에 대한 연 관성을 조사한 후, 중간 시험 및 최종 시험을 통해 플랫폼 활용에 대한 점수 향상 정도, 응시시간 변화 등 요인을 측정하였다. 초기 시 험을 통해 개인 요인(예: 토익 점수, 본인 스스로에 대한 영어능력 평가)에 따른 그룹 간 해사영어시험 점수에 유의한 차이가 있음을 확인하였으며, 중간시험 및 최종시험을 통해 플랫폼 활용이 유의한 시험점수 향상으로 이어졌음을 확인하였다. 해당 연구는 해사 교육 분야에 다양하게 적용할 수 있는 학습 플랫폼 활용 효능을 조사하였으며 향후 해사영어 교육 외 그 범위를 넓혀 활용될 수 있을 것으 로 사료된다.

Along with other heavy metals, arsenic (As) is one among the substances most harmful to living organisms including humans. Owing to its morphological similarity to phosphorus, the uptake of As is influenced by photosynthesis and the phosphorus uptake pathway. In this study, we varied arsenic exposure and light intensity during nutrient solution cultivation of lettuce (Lactuca sativa L.) to determine the effect of these two factors on arsenic uptake, lettuce growth, and electron transfer in photosystem II. In the treatment exposed to 30 μmol L-1 of arsenic, the shoot arsenic concentration increased from 4.73 mg kg-1 to 18.97 mg kg-1 as the light intensity increased from 22 to 122 μmol m-2 s-1. The water content and ET2o/RC of the shoots were not affected by arsenic at low light intensity; however, at optimal light intensity, they decreased progressively with arsenic exposure. Increased light intensity stimulated the growth of plant roots and shoots; contrarily, the difference in growth decreased as the concentration of As exposure increased. The results of this study suggest that the effect of As on plant growth is dependent on light intensity; in particular, an increase in light intensity can increase the uptake of As, thereby affecting plant growth and As toxicity.

Hypertension is characterized by excessive renin-angiotensin system activity, leading to blood vessel constriction. Several synthetic compounds have been developed to inhibit renin and angiotensin-converting enzyme (ACE). These drugs often have adverse side effects, driving the exploration of plant protein-derived peptides as alternative or supplementary treatments. This study assessed the phenolic compound and amino acid content and the antioxidant and antihypertensive activity of 5 South Korean staple crops. Sorghum had the highest phenolic compound content and exhibited the highest antioxidant activity. Millet grains, particularly finger millet (38.86%), showed higher antihypertensive activity than red beans (14.42%) and sorghum (17.16%). Finger millet was found to contain a large proportion of branched-chain, aromatic, and sulfur-containing amino acids, which are associated with ACE inhibition. In particular, cysteine content was positively correlated with ACE inhibition in the crops tested (r=0.696, p<0.01). This study confirmed that the amino acid composition was more correlated with the antihypertensive activity of grains than the phenolic compound content. Finger millet mainly contained amino acids, which have higher ACE inhibitory activity, resulting in the strongest antihypertensive activity. These findings underscore the antihypertensive potential of select crops as plant-based food ingredients, offering insight into their biological functions.

Abstract Purpose : The distribution of axial length and ocular dimensions was investigated, and each correlation according to gender and age was investigated. Methods : Among 847 eyes of 438 patients, 207 eyes in 20s, 210 eyes in 30s, 216 eyes in 40s, and 214 eyes in 50s were measured for axial length with IOL-Master 700. Refractive error was measured with KR-800. Corneal curvature radius and corneal eccentricity were measured with Keratograph 4. Results : Axial length (male: 24.57±1.22mm, female: 24.03±1.12mm) and horizontal corneal eccentricity (male: 0.58±0.11, female: 0.54±0.12) tended to increase in decreased age, male and myopia. Mean corneal curvature radius (male: 7.82±0.25mm, female: 7.71±0.25 mm), and horizontal corneal curvature radius (male: 7.91±0.26 mm, female: 7.79±0.26mm), nasal corneal eccentricity (male: 0.68±0.14, female: 0.66±0.15), and temporal corneal eccentricity (male: 0.45±0.14, female: 0.44±0.13) tended to increase in decreased age and male. Mean corneal eccentricity (male: 0.57±0.12, female: 0.54±0.12), vertical corneal curvature radius (male: 7.71±0.27 mm, female: 7.65±0.24 mm), vertical corneal eccentricity (male: 0.56±0.15, female: 0.54±0.15), and inferior corneal eccentricity (male: 0.52±0.19, female: 0.46±0.22) tended to increase in male. The correlation with axial length and corneal curvature radius showed a high correlation in emmetropia and the horizontal. Horizontal and temporal corneal eccentricity showed a low correlation. Conclusion : Axial length, corneal curvature radius, and corneal eccentricity (excluding vertical) were higher in males. As age increased, axial length, and corneal curvature radius decreased. Among the 4 quadrants of corneal eccentricity, only the temporal s ide showed a significant correlation with axial length. Key words : Age, Axial length, Corneal curvature radius, Corneal eccentricity, Gender Authors ORCID:†

Abstract Purpose : The aim of this study was to identify knowledge and lifestyle habits for glaucoma prevention and to present basic data for future glaucoma prevention education. Methods : From April to September 2023, 447 people in their 20s to 60s were selected and an online survey was conducted. The questionnaire consisted of a total of 30 questions, including 6 questions about the subject's general characteristics, 14 questions about knowledge and awareness of glaucoma, and 10 questions about lifestyle habits related to intraocular pressure. Results : 89.7% responded that they had heard of glaucoma, and 31.1% of respondents knew the difference between glaucoma and cataracts. 34.5% responded that early detection is difficult, 33.3% that complete treatment is difficult, 23.5% that even normal intraocular pressure can cause glaucoma, and 36.0% that the incidence of glaucoma is increasing day by day. The level of awareness and knowledge was higher with age, in women than men, in those with a family history, in professional occupations, with metabolic diseases, and with high myopia. Lifestyle habits related to intraocular pressure were higher with age, among women, when smartphone use was less than 3 hours, and among housewives and professionals. The relationship between glaucoma knowledge and awareness and intraocular pressure-related lifestyle habits was statistically significant (r=0.248, p<0.001). Conclusion : Although the level of basic knowledge about glaucoma was high, the level of specific knowledge was low compared to the increase in the incidence of glaucoma over the past 10 years. Key words : Glaucoma, Healthy Life Practices, Intraocular pressure

This study investigated the effects of exposure frequency, depth of processing, and activity repetition types on vocabulary learning. In total, 78 South Korean fifth-grade students were divided into four conditions. Students in each condition were asked to read a passage with four of the eight target words (exposure: four times) and the other four words (exposure: once) for three days, and to perform the vocabulary activities assigned to each condition. According to the results, exposure frequency and activity repetition type had significant effects on vocabulary learning. Activity repetition type also had a significant interaction effect with exposure frequency and depth of processing. Notably, presenting a word 12 times (4x3) in reading intervals had a more positive impact on vocabulary learning than presenting it three times (1x3), particularly when different vocabulary activities were repeated. Meanwhile, when the same activity was repeated, an activity with a higher depth of processing was more effective for vocabulary learning.

Background: Estrus in cows can be detected through vaginal electrical resistance or conductivity. However, there are no studies measuring vaginal electrical resistance in Hanwoo cows. This study aims to measure the vaginal electrical resistance value in Hanwoo cows and compare it with estrus and ovulation. Methods: Vaginal electrical resistance values of 73 Hanwoo cows were measured before and after estrus at the Gyeongsangbuk-do Livestock Research Institute. Measurements were taken on days -6, -3, -2, -1, 0, 1, 2, 3, and 6 of artificial insemination. Large follicles and ovulation were confirmed using transvaginal ultrasonography. Results: The vaginal electrical resistance averaged 225.6 ± 6.3 Ω days before the artificial insemination date, decreasing until the day of artificial insemination. The average vaginal electrical resistance was 163.7 ± 4.6 Ω on the date of artificial insemination, and 188.8 ± 4.3 Ω one day after artificial insemination, when large follicles were observed. In addition, on the 6th day after artificial insemination, the vaginal electrical resistance averaged 231.4 ± 5.5, which was similar to the 6th day before artificial insemination (222.5 ± 6.3). Transvaginal ultrasonography showed that most of the cows ovulated one day after artificial insemination. Conclusions: The accuracy of estrus is high if the vaginal electrical resistance is measured for cows with confirmed estrus, making is a potentially useful for determining the timing of artificial insemination.