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        검색결과 2,509

        21.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Milky white spots appeared on red bean leaves in a red bean cultivation area located in Jangyeon-myeon, Goesan-gun, Chungbuk Province. After culturing the pathogen in PDA medium, their morphology was observed, and their genes were BLAST-searched in the National Center for Biotechnology Information (NCBI). The pathogen was identified as a fungus called Rhizopus arrhizus. As a result of reinoculating the isolated pathogen on red beans, the same symptoms as those in the isolated leaves occurred. Characteristic colonies of R. arrhizuson PDA medium initially showed a bright color and then changed to dark gray over time, with mostly spherical sporangia. The sporangiospores were spherical or elliptical, mostly irregular, and small in size. Therefore, based on these results, this disease has not yet been reported in red beans and was called red bean brown leaf blight caused by Rhizopus arrhizus A. Fisch (syn. R. oryzae).
        4,000원
        22.
        2023.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The theoretical capacity of silicon-based anode materials is more than 10 times higher than the capacity of graphite, so silicon can be used as an alternative to graphite anode materials. However, silicon has a much higher contraction and expansion rate due to lithiation of the anode material during the charge and discharge processes, compared to graphite anode materials, resulting in the pulverization of silicon particles during repeated charge and discharge. To compensate for the above issues, there is a growing interest in SiOx materials with a silica or carbon coating to minimize the expansion of the silicon. In this study, spherical silica (SiO2) was synthesized using TEOS as a starting material for the fabrication of such SiOx through heating in a reduction atmosphere. SiOx powder was produced by adding PVA as a carbon source and inducing the reduction of silica by the carbothermal reduction method. The ratio of TEOS to distilled water, the stirring time, and the amount of PVA added were adjusted to induce size and morphology, resulting in uniform nanosized spherical silica particles. For the reduction of the spherical monodisperse silica particles, a nitrogen gas atmosphere mixed with 5 % hydrogen was applied, and oxygen atoms in the silica were selectively removed by the carbothermal reduction method. The produced SiOx powder was characterized by FE-SEM to examine the morphology and size changes of the particles, and XPS and FT-IR were used to examine the x value (O/Si ratio) of the synthesized SiOx.
        4,000원
        23.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The occurrence of eggs and adults of Pochazia shantungensis, Lycorma delicatula, and Lymantria dispar was investigated in 11 cities in the Chungcheongbukdo region. The results showed that the overwintering eggs of P. shantungensis occurred in 24.2% of the region in 2021 and 22.1% in 2022, while adults occurred in 25.2% in 2021 and 24.3% in 2022, indicating the highest occurrence among the pests studied. The occurrence of overwintering eggs of L. delicatula was relatively low, with 2.6% of the region affected in 2021 and 1.9% in 2022. Adult L. delicatula occurred in 3.2% of the region in 2021 and 3.6% in 2022. Overwintering eggs of L. dispar occurred in 4.1% of the area in 2021 and 1.7% in 2022, showing a decreasing tendency compared to the previous year, and their occurrence was only low to middle in terms of the degree of occurrence. Adult L. dispar occurred in 4.6% of the region in 2021 and 2.7% in 2022, showing occurrences that were insignificant compared to L. delicatula. According to a survey of host preferences, both the wintering eggs and adults of P. shantungensis were found in apples and peaches between 2021 and 2022. In both 2021-2022, adult L. delicatula had a high incidence in peaches, apples, and grapes, and winter eggs were the highest in grapes. However, the incidence in apples and peaches was low. A high incidence density of L. dispar moth adults and overwintering eggs was found in apples in both 2021 and 2022.
        4,200원
        24.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Aluminum alloys, known for their high strength-to-weight ratios and impressive electrical and thermal conductivities, are extensively used in numerous engineering sectors, such as aerospace, automotive, and construction. Recently, significant efforts have been made to develop novel aluminum alloys specifically tailored for additive manufacturing. These new alloys aim to provide an optimal balance between mechanical properties and thermal/ electrical conductivities. In this study, nine combinatorial samples with various alloy compositions were fabricated using direct energy deposition (DED) additive manufacturing by adjusting the feeding speeds of Al6061 alloy and Al-12Si alloy powders. The effects of the alloying elements on the microstructure, electrical conductivity, and hardness were investigated. Generally, as the Si and Cu contents decreased, electrical conductivity increased and hardness decreased, exhibiting trade-off characteristics. However, electrical conductivity and hardness showed an optimal combination when the Si content was adjusted to below 4.5 wt%, which can sufficiently suppress the grain boundary segregation of the α- Si precipitates, and the Cu content was controlled to induce the formation of Al2Cu precipitates.
        4,000원
        25.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 지카바이러스, 메르스, coronavirus disease-19 (COVID-19) 등의 감염병 방역 및 의료현장에서 사용할 수 있는 의료용 공기정화호흡기(powered air purifying respirators, PAPR)의 항균성 보호복의 후드와 필터를 개발하였다. PAPR은 전동팬 본체 및 필터, 배터리팩, 후드로 구성되며 보호복의 후드 소재는 뛰어난 흡습성, 풍압, 외부충격을 견딜 수 있는 폴리프로필렌 슐폰레이스(spunlace) 부직포 직물(SFS)을 사용하였다. 사용자의 감염위험을 낮추기 위해 후드의 외피에는 피톤치드계 물질을 사용하여 99.9%의 안티-박테리얼(antibacterial) 효과를 얻었으며 내피에는 친수가공을 하여 흡수성을 25% 향상시켰다. 의료용 보호복 후드에 필요한 인공혈액 침투저항성, 건조미생물 침투저항성, 습식세균 침투저항성, 그리고 박테 리오파아지 침투저항성을 평가한 결과 2~6 단계의 합격평가를 받았다. 한편, 항균 처리된 슐폰레이스(spunlace filter, SF) 헤 파 필터(high efficiency particulate air, HEPA)의 성능을 평가한 결과 우수한 항균성, 분진제거율, 차압 효과를 확인하였다.
        4,200원
        26.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study analyzed the monitoring results of fishways at 16 weirs constructed on four large Rivers to provide data helpful for the operation and management of fishways. The average utilization rate of the fishways at the weirs was confirmed to be 64.9%. When comparing the dominant species in the mainstream and fishway monitoring results, differences were observed in 9 weirs (56.3%). This indicated that the species prevalent in the mainstream were not necessarily the ones most frequently using the fishways. The average number of individuals using the fishways per day was 336. When classifying the fish species using the fishway by life type, 92.3% were primary freshwater fish, and migratory species accounted for only 5.6%. Analysis based on the season of fishway usage revealed that an average or higher number of fish species used the fishways from May to October, with the highest number of individual users occurring from June to August. Between May and July, 80% of the fish species using the fishways were in their spawning period, while during other season, less than 40% were species that move during the spawning period. The fishways that showed a significant alignment between the spawning period and the fishway passage period were Rhinogobius brunneus, Leiocassis nitidus, Squalidus chankaensis tsuchigae, Pseudogobio esocinus, Acheilognathus rhombeus, and Pungtungia herzi, in that order. When comparing the fishway monitoring results of the Gangjeong-Goryeong Weir and the Dalseong Weir with the upper part water level of the weir, both the number of fish species and individuals using the fishway showed positive correlations with the upper part water level of the weir. This suggests that a higher water level of the weir increases the inflow discharge within the fishway, leading to increased use by fish (number of individuals in Gangjeong-Goryeong Weir, P<0.001; number of species in Dalseong Weir, P<0.05). This study summarized and analyzed the results of fishway monitoring at 16 weirs built on four large Rivers, considering fishway efficiency, operation and management, monitoring period, and regulation of water level in the upper part of the weir. It is thought that this will help understand the status of fish use in fishways on large River and aid the construction, operation, and management of fishways in the future.
        4,800원
        27.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study is to identify the major peacekeeping activities that the Korean armed forces has performed from the past to the present. To do this, we collected 692 press releases from the National Defense Daily over the past 20 years and performed topic modeling and social network analysis. As a result of topic modeling analysis, 112 major keywords and 8 topics were derived, and as a result of examining the Korean armed forces's peacekeeping activities based on the topics, 6 major activities and 2 related matters were identified. The six major activities were 'Northeast Asian defense cooperation', 'multinational force activities', 'civil operations', 'defense diplomacy', 'ceasefire monitoring group', and 'pro-Korean activities', and 'general troop deployment' related to troop deployment in general. Next, social network analysis was performed to examine the relationship between keywords and major keywords related to topic decision, and the keywords ‘overseas’, ‘dispatch’, and ‘high level’ were derived as key words in the network. This study is meaningful in that it first examined the topic of the Korean armed forces's peacekeeping activities over the past 20 years by applying big data techniques based on the National Defense Daily, an unstructured document. In addition, it is expected that the derived topics can be used as a basis for exploring the direction of development of Korea's peacekeeping activities in the future.
        5,100원
        28.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This experiment investigated the effects of feed additives of Sasa quelpaertensis Nakai (SQN) extract on Landrace pigs on economic traits such as the quality, physiological characteristics, and productivity. Sixteen pigs with an average age of 154 days were selected as experimental subjects. The experiment was conducted by dividing the group into eight pigs for the supplementation group, feeding with SQN extract, and another eight for the control group feeding without SQN extract. Water was fed ad libitum. On the 30th day, there was no significant difference between meat quality and productivity. However, the glucose and thyroxine were statistically lower with the supplementation group than with the control group (p<0.05). Also, the levels of creatinine difference between 1.18 ± 0.12 ㎎/㎗ with the supplementation group and 0.70 ± 0.06 ㎎/㎗ with the control group (p<0.05). However, all serum biochemistry values were within a normal range, with no health problems. The present study will help solve the problem of reducing the diversity of plant species in Halla Mountain by increasing the availability of the SQN as a pig feed additive.
        4,000원
        29.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study investigates the integration of astronomy-related topics in the Korean national science curricula spanning from 1945 to 2023. We analyze the placement and extent of astronomy content across different school levels. Astronomy contents in the science curricula have changed in response to social needs (e.g., practical knowledge required for agriculture and fishery) and advancement in astronomical research (e.g., the discovery of exoplanets and the suggestion of new cosmological parameters). Contents addressing the motions of celestial objects and stellar physical properties have remained relatively consistent. In the latest 2022 revised national curriculum, scheduled for implementation in 2024, several elements, such as coordinate systems, have been removed, while the inquiry activities using digital tools are emphasized. The incorporation of the cosmic perspectives in the national curriculum, as well as astronomy education within the context of education for sustainable development, remains limited even in the most recent curriculum. For future life revisions, the active participation of researchers is needed to reflect the latest astronomical research progress and scientific characteristics in the field of astronomy.
        5,700원
        30.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        eDNA (environmental DNA)란 특정 환경에 서식하는 생물로부터 유래한 DNA를 의미한다. 환경 시료로부터 추출한 eDNA를 활용하면 해당 환경에 서식하는 생물들의 효율적이고 정확한 모 니터링을 수행할 수 있다. 해수 시료로부터 얻은 eDNA를 기반으로 해양생물 다양성 연구를 수행할 수 있다. 해수 시료를 채집하고 이로부터 eDNA를 추출한 뒤, metagenome 분석을 통 해 서식하는 해양생물의 종 동정과 다양성 분석이 가능하다. 본 리뷰에서는 이처럼 해수의 eDNA를 활용하여 해양 지역의 생물 다양성 연구를 수행하는 전체적인 과정을 제시하고 있다. 아직 국내에는 해양생물 다양성 연구를 위해 eDNA를 적용하는 방법이 보편화 되어있지 않으 며, 본 리뷰를 기반으로 이와 같은 eDNA 연구 방법을 정립하는데 도움을 줄 수 있을 것이다.
        4,200원
        31.
        2023.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        To investigate residual pesticide levels in agricultural products contained in Meal-kits, 27 Meal-kit products were collected from marts, Meal-kit shops, and online stores in Incheon City, South Korea. Seventy-six vegetable and thirty-seven mushroom products were analyzed for residual levels of 339 pesticides. Residual pesticides were detected in 23 out of 76 vegetables and were not present in the 37 mushroom products. The residual pesticide detection rate was 20.4% (23/ 113 cases). The pesticides famoxadone 0.034 mg/kg (standard: 0.01 mg/kg or less, PLS) and fenpyroximate 0.302 mg/kg (standard: 0.01 mg/kg or less, PLS) exceeded their maximum residue levels (MRL). This survey revealed that various types of pesticides remain in agricultural products in Meal-kits. Due to the nature of Meal-kit products, there is no separate standard for residual pesticides in agricultural products. Therefore, continuous monitoring of residual pesticides is necessary.
        4,000원
        32.
        2023.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study established optimal cookie conditions by varying the amount of modified starch treated with octenyl succinic anhydride (OSA). It also investigated the quality and digestion characteristics of the cookies produced. The moisture content increased as the amount of OSA-modified starch added to the cookies increased. As for cookie color brightness, the redness and yellowness decreased as the OSA-modified starch content increased. The spread factor and hardness of the cookies showed the most similar results for control and OSA: 20%. As the amount of OSA-modified starch added to cookies increased, RS tended to increase. It was found that OSA-modified starch cannot easily replace wheat flour completely and that the optimal amount of OSA-modified starch added to cookies is 20%. OSA-modified starch can be used not only as a cookie but also as a low-calorie food ingredient.
        4,000원
        33.
        2023.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        막대한 예산이 투입되는 국가연구를 기획·관리·확산하는 연구관리 담당자들은 매우 중요한 인력이나, 역할에 관한 연구는 부족한 실정이다. 본 연구는 연구관리 전문기관 담당자에게 필요한 역량요소를 도출하고 역량의 중요도를 확인하고자 하였다. 이를 위해 4가 지 주요요인과 16개의 하위요인을 도출하였고, AHP 기법을 기반으로 설문조사(연구관리 담 당자와 연구자 90명 대상)를 추진하여 우선순위를 도출하였다. 전체 응답자 기준으로 역량의 중요도는 협력적 태도, 소통능력, 연구지식, 목표관리능력과 신의성실 순으로 확인되었으나, 담당자의 경우, 업무와 관련한 역량(규정지식, 판단능력, 정책지식)이 중요하다고 보는 반면, 연구자들의 경우 자신들을 보다 더 지원해 줄 수 있는 역량(협력적 태도, 소통능력)을 보다 더 중시하는 시각차를 볼 수 있었다. 이번 연구는 전문기관 연구관리 담당자의 채용과 역량 개발에 활용할 수 있을 것으로 사료된다.
        6,600원
        34.
        2023.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Purpose: This study aims to not only understand the meaning and essence of patients’experiences visiting the Raphael Nanum Homeless Clinic but also explore what kind of healthcare programs they would like to have in the future by appraising patients’experiences in depth. Methods: This study employed a qualitative content analysis method. The data were collected from June 11, 2023, to June 25, 2023. A total of 17 patients who could provide detailed experiences of their visit to the Raphael Nanum homeless clinic participated in this study. We conducted a focus group interview with 6 patients and in-depth one-on-one interviews with the remaining 11 patients. Results: The qualitative content analysis result revealed five themes: “visiting a free clinic for various paths,” “positive experiences at the free clinic,” “negative experiences at the free clinic,” “dissatisfaction with the clinic site,” and “anticipation for the future of the free clinic.” Conclusion: To ensure the right to health and survival of marginalized populations in the future, it is necessary to establish comprehensive healthcare support measures, which include enhancing the facilities of the free clinic and expanding the range of available medical specialties.
        4,900원
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