검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 628

        1.
        2024.09 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Pyrochemical processing and molten-salt reactors have recently garnered significant attention as they are promising options for future nuclear technologies, such as those for recycling spent nuclear fuels and the next generation of nuclear reactors. Both of these technologies require the use of high-temperature molten salt. To implement these technologies, one must understand the electrochemical behavior of fission products in molten salts, lanthanides, and actinides. In this study, a rotating-disk-electrode (RDE) measurement system for high-temperature molten salts is constructed and tested by investigating the electrochemical reactions of Sm3+ in LiCl–KCl melts. The results show that the reduction of Sm3+ presents the Levich behavior in LiCl–KCl melts. Using the RDE system, not only is the diffusion-layer thickness of Sm3+ measured in high-temperature molten salts but also various electrochemical parameters for Sm3+ in LiCl–KCl melts, including the diffusion coefficient, Tafel slope, and exchange current density, are determined.
        4,000원
        2.
        2024.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study evaluated the efficacy of a wild boar repellent (Repellent A) consisting of tannins and plant oils (castor oil, garlic oil, and cinnamon oil). Sixty farmed wild boars (4-8 months old) were divided into three groups: the normal control group (NC, n=20), the experimental group (EP, n=20), and the comparative experimental group (C-EP, n=20), which used Repellent B consisting of guaiacol, eugenol, menthol, thymol, and indole. EP and C-EP were equipped with four repellents per feeder, while no repellents were installed in the NC feeder. The feed intake and the number of feeding approaches were measured for one week in all groups. The number of approach of wild boars in feeders was monitored daily using a CCTV camera. The daily feed intake per farmed wild boar in EP and C-EP was significantly decreased compared to NC (p<0.05), and EP was significantly decreased compared to C-EP (p<0.05). In the average number of daily approaches, EP and C-EP were significantly decreased compared to NC (p<0.05), and EP was significantly decreased compared to C-EP (p<0.05). In conclusion, Product A has been confirmed to have excellent repellent effects on wild boars, and it could be used to prevent wild boars from approaching pig farms.
        3,000원
        3.
        2024.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study aims to establish an online shopping mall marketing strategy based on big data analysis methods. The customer cluster analysis method was utilized to analyze customer purchase patterns and segment them into customer groups with similar characteristics. Data was collected from orders placed over one year in 2023 at ‘Jeonbuk Saengsaeng Market’, the official online shopping mall for agricultural, fish, and livestock products of Jeonbuk Special Self-Governing Province. K-means clustering was conducted by creating variables such as ‘TotalPrice’ and ‘ElapsedDays’ for analysis. The study identified four customer groups, and their main characteristics. Furthermore, regions corresponding to customer groups were analyzed using pivot tables. This facilitated the proposal of a marketing strategy tailored to each group’s characteristics and the establishment of an efficient online shopping mall marketing strategy. This study is significant as it departs from the traditional reliance on the intuition of the person in charge to operate a shopping mall, instead establishing a shopping mall marketing strategy through objective and scientific big data analysis. The implementation of the marketing strategy outlined in this study is expected to enhance customer satisfaction and boost sales.
        4,200원
        4.
        2024.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The diversity of smart EV(electric vehicle)-related industries is increasing due to the growth of battery-based eco-friendly electric vehicle component material technology, and labor-intensive industries such as logistics, manufacturing, food, agriculture, and service have invested in and studied automation for a long time. Accordingly, various types of robots such as autonomous mobile robots and collaborative robots are being utilized for each process to improve industrial engineering such as optimization, productivity management, and work management. The technology that should accompany this unmanned automobile industry is unmanned automatic charging technology, and if autonomous mobile robots are manually charged, the utility of autonomous mobile robots will not be maximized. In this paper, we conducted a study on the technology of unmanned charging of autonomous mobile robots using charging terminal docking and undocking technology using an unmanned charging system composed of hardware such as a monocular camera, multi-joint robot, gripper, and server. In an experiment to evaluate the performance of the system, the average charging terminal recognition rate was 98%, and the average charging terminal recognition speed was 0.0099 seconds. In addition, an experiment was conducted to evaluate the docking and undocking success rate of the charging terminal, and the experimental results showed an average success rate of 99%.
        4,000원
        5.
        2024.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, an attempt was made to approximate the main characteristic values of Bi0.5(Na0.78K0.22)0.5TiO3 (= BNKT) depending on the content of Fe2O3 additives, aiming to approach the values of lead(Pb) piezoelectric ceramic materials (PZT). Specifically, when the piezoelectric coefficient (d33) value of lead(Pb) piezoelectric ceramic material (PZT polycrystalline ceramic powder) is 300[pC/N] or higher, it is applied for hard purposes such as ultrasonic welding machines and cleaning machines, and when it exceeds 330[pC/N], it is applied for soft purposes like piezoelectric sensors. In this study, research and development were conducted for devices with a piezoelectric coefficient (d33) of 300[pC/N] or more for actuators. For this purpose, K+ exceeding 0.02 to 0.12 mol% was added to (Na0.78K0.22)0.5Bi0.5TiO3 to analyze structural changes due to K+ excess, and (Na0.78K0.22)0.5Bi0.5TiO3 + 8mol% K2CO3 Ti4+ was substituted with Fe3+ to manufacture lead-free piezoelectric materials. As a result, ceramics with Fe3+ substitution at x = 0.0075 yielded an average value of d33 = 315[pC/N]. Furthermore, for ceramics with Fe3+ substitution at x = 0.0075, the average values of maximum polarization (Pmax), residual polarization (Prem), and coercive field (Ec) were found to be 39.63 μC/cm2, 30.45 μC/cm2, and 2.50 kV/mm, respectively. The reliable characteristic values obtained from the research results can be applied to linear actuator components (such as the zoom function of mobile cameras, LDM for skin care, etc.) and ultrasonic vibration components.
        4,000원
        7.
        2024.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: Most patients with chronic stroke have difficulty walking, and various exercise methods are used clinically to improve the disability. Among them, various methods are being applied to improve walking through torso movement. Objectives: This study was conducted to determine the effect of Maitland vertebra joint mobilization exercise and Evjenth trunk muscle stretching exercise on the walking ability of patients with hemiparesis due to chronic stroke. Design: A randomized controlled trial. Methods: In this study, 30 chronic stroke patients with hemiplegia were divided into 15 patients in the Maitland vertebra joint mobilization group (MVJMG) and 15 in the Evjenth trunk muscle stretching exercise group (ETMSEG), and the intervention was conducted for 3 weeks, 5 times a week, 30 minutes a day. After the intervention, walking ability was measured using a gait analyzer. Results: In terms of walking ability, there was a significant increase in walking rate, walking speed, and stride length following the intervention in both the MVJMG and ETMSEG groups (P<.05). When comparing the difference in walking ability between the two groups, there was no significant difference in walking rate. Conclusion: The study found that both Maitland vertebra joint mobilization and Evjenth trunk muscle stretching exercises were effective for improving walking function in chronic stroke patients. However, there was no significant difference in effectiveness between the two interventions.
        4,000원
        8.
        2024.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        From 2020, Korean Animal and Plant Quarantine Agency has reset the withdrawal time (WT) for veterinary drugs typically used in livestock in preparation for the introduction of positive list system (PLS) program in 2024. This study was conducted to reset the MRL for tiamulin (TML) in broiler chickens as a part of PLS program introduction. Forty-eight healthy Ross broiler chickens were orally administered with TML at the concentration of 25 g/L (TML-1, n=24) and 50 g/L (TML-2, n=24) for 5 days through drinking water, respectively. After the drug treatment, tissue samples were collected from six broiler chickens at 1, 2, 3 and 5 days, respectively. According to the previously established analysis method, residual TML concentrations in poultry tissues were determined using LC-MS/MS. In TML-1, TML in all tissues was detected less than LOQ at 2 days after drug treatment. In TML-2, TML in liver and kidney was detected more than LOQ at 2 days after treatment. According to the European Medicines Agency’s guideline on determination of withdrawal periods, withdrawal periods of TML-1 and TML-2 in poultry tissues were established to 0 and 2 days, respectively. In conclusion, the estimated WT of TML in poultry tissues is shorter than the current WT recommendation of 5 days for TML in broiler chickens.
        4,000원
        10.
        2024.04 구독 인증기관·개인회원 무료
        The family Baetidae is known to be the most species-rich family in the order Ephemeroptera. The genus Baetis contains up to 160 species, but members of the genus in East Asia are still poorly investigated. In this paper, Baetis spinoculis sp. nov., is described based on larval specimens collected in a stream of the Chiaksan mountain in Korea. While four species in the genus have been described in Korea: Baetis fuscatus (Linnaeus), B. silvaticus Kluge, B. pseudothermicus Kluge, and B. ursinus Kazlauskas, this new species is distinguished from other Korean baetid species by both genetic and morphological characteristics. B. spinoculis can be separated from the related B. pseudothermicus group by the COI genetic distant. The cuticle structures on paraproct plates and abdominal pigment patterns also distinguish B. spinoculis from B. pseudothermicus and other related species.
        11.
        2024.04 구독 인증기관·개인회원 무료
        The mayfly genus Drunella is the most diverse genera in the family Ephemerellidae, and is found in lotic streams throughout East Asia and North America. The species D. ishiyamana is found widely throughout East Asia and their species concept has not been properly defined until recently. The D. ishiyamana species group was examined, and morphological and molecular evidence of a new species were uncovered. In this study Drunella punctata sp. nov. is formally described, mainly distinguished from D. ishiyamana by the lack of a notch in their median clypeal tubercle in their larval stage. Photographs, diagnosis, and descriptions of D. punctata are provided.
        12.
        2024.04 구독 인증기관·개인회원 무료
        This research introduces the subfamily Catotrichinae to the South Korean fauna for the first time. Within the globally recognized 6,651 Cecidomyiidae species, only ten are categorized under the Catotrichinae subfamily. Notably, this subfamily, which ingests fungi during larval development, is among the most primordial lineages of the Cecidomyiidae, both in morphological and molecular terms. The species Catoricha nipponensis of Catotrichinae was newly observed in Yeongwol, Gangwon-do, in October 2021. It was recorded for the first time in Korea, with its holotype initially collected in Honshu, Japan, in November 1923. This study provides the diagnosis, photographs of distinguishing characteristics, and the DNA barcode sequences for Catotricha nipponensis. This work was supported by a grant from the National Institute of Biological Resources (NIBR), funded by the Ministry of Environment (MOE) of the Republic of Korea.
        13.
        2024.04 구독 인증기관·개인회원 무료
        The genus Campylomyza Meigen, 1818, from the Micromyinae subfamily of the Cecidomyiidae, includes 40 known species globally. The genus Campylomyza has been primarily studied within the Palearctic region, with 39 species, 2 from the Nearctic region, and 1 from the Oriental region. As of now, four species have been documented in Korea: Campylomyza appendiculata, C. flavipes, C. furva, and C. spinata. Our research from 2017 to 2020 uncovered five previously unreported species in Korea (C. abjecta, C. aborigena, C. cornuta, C. cavitata, and C. cingulata) and introduces seven new species (C. angusta sp. nov., C. ambulata sp. nov., C. convexa sp. nov., C. cornigera sp. nov., C. hori sp. nov., C. odae sp. nov., and C. yeongyangensis sp. nov.). These findings are based on morphological evidence and DNA analysis. We present comprehensive data, including the mitochondrial COI sequences, diagnoses, detailed descriptions, and identification keys for these species. This work was supported by a grant from the National Institute of Biological Resources (NIBR), funded by the Ministry of Environment (MOE) of the Republic of Korea.
        14.
        2024.04 구독 인증기관·개인회원 무료
        Neomyrhessus Minkina, 2024, is a rare genus comprising six species, recently erected from Myrhessus Balthasar, 1955 for N. nanjingensis. To date, all six species have been reported in East Asia, with five from Japan and one from China. In this study, the genus Neomyrhessus is recorded for the first time in South Korea, with the discovery of a new species Neomyrhessus coreanus sp. nov. Description, illustrations of morphological characters, and habitat information for a new species are provided.
        15.
        2024.04 구독 인증기관·개인회원 무료
        The genus Hypsopygia was established by Hübner, 1825, with type species Phalaena costalis Fabricius, 1775. Hypsopygia is characterized by the elongated uncus and valva, and pointed saccus in the male genitalia. It consists of 105 described species (Nuss et al., 2003–2024) in the world, and 11 species have been recorded in Korea (Kim & Paek, 2020; Shin et al., 2023). In this study, we reported one newly recorded species in Korea. Illustrations of adults provided, with information of host plants of all examined species.
        16.
        2024.04 구독 인증기관·개인회원 무료
        The genus Olethreutes, established by Hübner in 1822, is based on the type species Phalaena arcuella Clerk, 1759. Olethreutes is one of the largest group within the family Tortricidae, with more than 130 species worldwide. As of now, about 31 species of the genus Olethreutes have been reported in the Korean peninsula. The proposes of this study is to describe one new species, with three similar species form Korea.
        17.
        2024.04 구독 인증기관·개인회원 무료
        A taxonomic study was conducted on Spilonota Stephens, 1834 in Korea. As a result of the research based on materials from Incheon National University two new species; S. samseong Choi, Bae & Nasu, and S. laticucullusa Choi, Bae & Nasu from Korea. This study provides a brief description of the new Spilonota species in Korea, as well as comparisons with similar species and illustrations of adult and genital morphology.
        18.
        2024.02 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Nanoparticles are commonly used to avoid the opaque white color of TiO2 based sunscreen. However, a dispersing agent is typically required because of the tendency of the nanoparticles (NPs) to agglomerate. Stearic acid is one kind of dispersing agent often used for sunscreen products. However, according to the MSDS data sheet on stearic acid, stearic acid is highly hazardous to aquatic life and causes irritation on human skin. To avoid this problem, in this study a safer organic dispersing agent extracted from Korean seaweed has been studied to disperse TiO2 nanoparticles, and further use as an active agent in sunscreen products. The presence of phytochemicals in seaweed extract, especially alginate, can disperse TiO2 nanoparticles and improve TiO2 dispersion properties. Results show that seaweed extract can improve the dispersion properties of TiO2 nanoparticles and sunscreen products. Reducing the agglomeration of TiO2 nanoparticles improves sunscreen properties, by making it less opaque white in color, and increasing UV protection value. It was also confirmed that adding seaweed extract into sunscreen products had no irritating effects on the human skin, making it more desirable for cosmetics application.
        4,000원
        19.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: In community-dwelling elderly individuals, slower gait speed is closely related to the ground reaction force. In the elderly with fall experience, stride length and gait speed, and other gait parameters are closely related to gastrocnemius activation. Objectives: To investigate whether medial gastrocnemius stiffness influences gait parameters in community-dwelling elderly people who experienced falls. Design: Cross sectional study. Methods: A total of 149 community-dwelling older adults were assigned to the faller and non-faller groups. Gait parameters (step length, stride length, step width, cadence, heel and toe ground reaction force, heel and toe contact time), and stiffness of the medial and lateral gastrocnemius and tibialis anterior were measured using shear wave elastography. Results: Elderly fallers had shorter step and stride length, lower cadence and toe ground reaction force and heel contact time, and lower medial gastrocnemius stiffness than non-fallers. In elderly fallers, medial gastrocnemius stiffness was significantly correlated with step and stride length, step width, toe ground reaction force, and heel contact time. Conclusions: Lower medial gastrocnemius stiffness in the elderly fallers decreases gait parameters, which can be a risk factor for falls. Therefore, medial gastrocnemius stiffness is a major factor that may associated gait parameters that can determine the risk of fall in community-dwelling elderly individuals.
        4,000원
        20.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to reset the maximum residue limit (MRL) for didecyldimethylammonium chloride (DDAC) in broiler chickens. The disinfectant containing DDAC (10%, w/w) was diluted 160 times and evenly sprayed on the bodies of twenty-four broiler chickens at a rate of 15 mL per day per bird for 7 days. After the disinfectant treatment, tissue samples were collected from six broiler chickens at 0.25, 1, 3 and 5 days, respectively. Residual DDAC concentrations in poultry tissues were determined using LC-MS/MS. Correlation coefficient (0.99 >), the limits quantification (LOQ, 2.0~10.0 μg/kg), recoveries (86.9~118.6%), and coefficient of variations (<19.98%) were satisfied the validation criteria of Korean Ministry of Food and Drug Safety. In all tissues except for liver, DDAC was detected more than LOQ at 5 days after the disinfectant treatment. In liver tissues, DDAC was detected more than LOQ at 3 days after treatment. According to the European Medicines Agency’s guideline on determination of withdrawal periods, withdrawal period of DDAC in poultry tissues was established to 26 days. In conclusion, the developed analytical method is sensitive and reliable for detecting DDAC in poultry tissues. When DDAC disinfectant is sprayed on a poultry house in the presence of broiler chickens, it is necessary to keep the disinfectant from contacting the body of the livestock.
        4,000원
        1 2 3 4 5