검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 8,441

        110.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The annual reproductive cycle of two species, Upogebia major (de Haan 1841) and Austinogebia wuhsienweni (Yu 1931), of the female mud shrimp from the west coast of Korea was investigated using histology. The collected samples were divided into adult and juvenile groups to understand the mature period of age class based on the carapace length (CL). Juvenile Upogebia (CL<25 mm) were mostly inactive gonad with early (62%-100%) and late (10%-38%) development stages during the year, whereas the adult shrimp showed a seasonal pattern of gonad maturation (CL≥25 mm). The early and late developmental stages of oocytes were observed in adult Upogebia from November to March and mature eggs appeared from April to October. In adult Ausitnogebia (CL≥15 mm), fully grown oocytes were consistently observed during the study period, in which the ripe stage was found between January and June. On the other hand, most juvenile Austinogebia (CL<15 mm) maintained an immature state in the gonad. Both species of the mud shrimp reproduced from ovigerous females in the adult population and their egg-bearing period was distinguished from January to April for U. major and from July to September for A. wuhsienweni.
        4,000원
        111.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        ATP luminescence measurements (using Relative Light Units, RLU) has been used to assess the levels of bacterial contamination on the surfaces of various materials. However, not much is known about their suitability in assessing bacterial contamination on paper surfaces. This study was conducted to evaluate the feasibility of using ATP luminometers in measuring levels of bacteria contamination on paper surfaces. The three ATP luminometers studied were Clean-Q, smart PD-30, and 3M™ Clean-Trace™ LM1 manufactured by different companies. There were some differences in RLU results among the three ATP luminometers when they were tested with different concentrations of Micrococcus luteus cell suspension. 106 - 107 cells were required in order to effectively detect Bacillus subtilis, Escherichia coli, and Micrococcus luteus on the surfaces of A4 printing sheets (100 cm2) when using the three ATP luminometers. The sizes and physical properties of surface areas varied slightly among the swabs used for the three ATP luminometers. Concentration-specific measurements (RLU) of M. luteus taken from the surfaces of six kinds of paper (fine print paper, medium print paper, ground paper, newsprint paper, practice paper, tracing paper) were possible using the smart PD-30 and LM1 ATP luminometers. ATP detection values of M. luteus varied among the six types of paper. The highest ATP detection values were found on the surfaces of tracing paper. If the RLU value is recorded at the level of 1000, this could indicate a very high bacterial contamination level of 105 to 106 CFU/4 cm2.
        4,000원
        112.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구의 목적은 오수견의 구전적 설화를 중심으로 돌비의 출토 및 현 오수면 원동공원과의 연계성을 통해 오수의 지명적 가치를 분석하는 것이 다. 아울러 오수면에 위치한 의견공원, 김개인 생가 등 풍수적인 물형가치 를 찾아 구전에 합당한 공간을 설정하고, 이 설정이 구전적 오수의견(義犬) 과 부합하는 지리적 형상을 이해하고자 하였다. 오수의견은 구전이나 나름 의 역사성을 갖추고 있는 문헌적 사료(史料)가 있으며 그와 관련하여 오늘 날까지도 이 지역주민들의 사랑을 받고 있는 공간이기도 하다. 그러므로 오수면의 의견스토리가 담긴 공간성은 반려견문화 세계화에 따라서 더욱 그 의미의 확장성을 보일 수 있다. 이러한 관점에서 오수면의 정체성과 지 명 그리고 전반적인 인문학적 연구가 더욱 필요할 것이다. 또한 의견의 구 전적 이야기와 합치하는 풍수적 의견물형(義犬物形)을 더하고 구전적 오수 견 이야기의 토대를 돌비출현과 연관 지어 스토리의 완성적 공간을 확장하 였다. 본 연구는 단순히 구전적 이야기로만 전해오던 인간과 반려견(의견) 과의 인격적 애정관계를 통해서 그들 간의 생명관을 고찰함과 동시에 오수 의견 이야기의 실제적 역사로서 그 가능성을 살펴보고자 하였다. 또한 오 수의견 이야기의 주 무대로 알려진 오수면의 지명적 정체성을 알아보고 그 의미를 바탕으로 오수의견과의 연결성 있는 스토리를 찾아보고자 하였다.
        6,300원
        113.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Invasive predators are one of the most damaging species groups to biodiversity. In the Nakdong River, the lake skygazer Chanodichthys erythropterus is a dominant species that is fiercely carnivorous and a concern for commercial fish. Although it is important to understand the ecological characteristics related to the feeding habit, studies on the diets of lake skygazer in Nakdong River have been limited to studies of gut contents. In this study, the trophic position (TP) and feeding habits of C. erythropterus were studied by calculating TPs using samples collected from 13 sites throughout the Nakdong River. Compound-specific isotopic analysis of amino acids provided reliable TPs from the muscle of Lake skygazer C. erythropterus without any isotope baseline. The results were approximately 3 to 3.6 and suggesting a carnivorous but size-dependent prey variation. In particular, the TP variability of C. erythropterus observed in the Nakdong River showed that it had a selective feeding habit compared to carnivorous fish species of relatively similar trophic levels.
        4,200원
        114.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, we analyzed the changes in concentrations of volatile fatty acids (VFA), phenols, and indoles, as well as odor contribution in pig slurry. The pig slurry was stored for approximately two months after the manure excretion of pigs which had been fed 3% level of peat moss additive. The investigation was carried out through lab-scale experiments simulating slurry pit conditions within pig house. Throughout the storage period, the concentration of VFA exhibited a tendency to be 11%-32% higher in the pig manure treated with peat moss as compared to the control group. From a concentration perspective, phenol and acetic acid accounted for the majority of the total odor compounds produced during the pig slurry storage period. However, their significance diminished when the concentration of odoros compounds are converted into odor activity value and odor contribution. Despite the odor reduction effect of the ammonia (NH3) adsorption by peat moss, if it cannot effectively reduce the high odor-contributing compounds such as indoles and p-cresol, the sole use of peat moss may not be considered an effective means of mitigating odors produced by pig slurry. According to this study, indoles, p-cresol, skatole, and valeric acid were consistently revealed as major odor-contributing substances during the two-month storage of pig slurry. Therefore, a comprehensive odor mitigation methodology should be proposed, taking into consideration the odor generation characteristics (including temporal concentration and odor contribution) of pig slurry-derived odors during storage.
        4,200원
        115.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study was to determine the conditions necessary for the total eradication of mite pests in indoor environments. The study involved the construction of a sterilization experimental setup. For this setup, various sterilization techniques, such as UV-C, ozone, ultrasound, and heat were applied, based on previous research. The experimental procedure consisted of placing mite pests in a chamber and subjecting them to different sterilization techniques. Observations were conducted immediately after the experiment and repeated five days later to assess the extent of eradication. The results showed that UVC, ozone, and ultrasound methods were not successful in completely eradicating the mite pests. In contrast, heat sterilization demonstrated effectiveness depending on the specific temperature and exposure time. To achieve the eradication of mite pests in indoor environments, it is necessary to maintain conditions of short-term high-temperature sterilization above 65°C or sustain temperatures above 50°C for a minimum duration of 90 minutes.
        4,000원
        116.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        To cultivate pine mushroom (Tricholoma matsutake) artificially, co-cultivation with microorganisms has been introduced. Here, experiments were performed to assess the growth-promoting effect of bacteria on T. matsutake mycelia. Bacteria were isolated from soil samples collected in Yangyang County, Korea. Four of the bacterial isolates (Y22_B06, Y22_B11, Y22_B18, and Y22_B22) exhibited a growth-promoting effect on T. matsutake mycelia (154.67%, 125.91%, 134.06%, and 158.28%, respectively). To analyze the characteristics of the bacteria, especially the antifungal activity, -amylase and cellulase activity assays were performed. In comparison with the controls, the isolated bacteria exhibited low -amylase and cellulase activity. 16S rRNA gene sequencing was performed to identify the four bacterial isolates. The isolates belonged to the Terrabacteria group and were identified as Microbacterium paraoxydans, Paenibacillus castaneae, Peribacillus frigoritolerans, and P. butanolivorans. These bacterial isolates are expected to have contributed to the growth promotion of T. matsutake mycelia and the artificial cultivation of T. matsutake.
        3,000원
        117.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to develop a renewable and sustainable bio-material to replace polystyrene (EPS) in fungal-mycelium-based composite using agricultural by-products. Four mushrooms (Ganoderma lucidum, Fomitella fraxinea, Phellinus linteus, and Schizophyllum commune) were cultured in an oak sawdust plus rice bran substrate to select the mushroom with the best growth. The mycelia of G. lucidum showed the best growth. To investigate the optimal mixing ratio with spent mushroom substrate (SM) and oak sawdust (OS), samples were prepared by mixing SM and OS at ratios of 50%:50%, 60%:40%, and 80%:20% (w/w). Each substrate was then inoculated with G. lucidum. G. lucidum showed the best mycelial growth of 140.0 mm in the substrate with SM and OS mixed at a 60%:40% ratio. It was also found that the substrate with SM and OS mixed at a 60%:40% ratio had the best handling properties. The compressive strength of mycelial materials inoculated with G. lucidum was in the range of 300–302 kgf mm-1, and the materials were four times stronger than polystyrene materials. These results indicate that substrates comprising spent mushroom substrate mixed with oak sawdust can be successfully upcycled to mycelium-based composite materials using G. lucidum. This represents a sustainable approach.
        4,000원
        118.
        2023.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, the characteristics and taste components of six different oyster mushroom cultivars (Gonji-7ho, Santari, Baekseon, Chunchu, Suhan, and Heuktari) were analyzed and compared. The Heuktari mushroom pileus had the lowest brightness index (32.8) and remained dark (brightness index: 30.5) even after blanching. The moisture content of the mushrooms was approximately 90%. The salinity and sugar contents were highest in Heuktari (5.7% and 7.1%, respectively). Gonji -7ho had the highest contraction rates, with a length contraction rate of 16.4% and thickness contraction rate of 23.9%. The total amino acid content was highest in Heuktari (537.8 mg/100 g), but the glutamine content contributing to umami taste was highest in Santari (59.4 mg/100 g) and the aspartic acid content was highest in Baekseon (33.1 mg/100 g). Among the 5?-nucleotide components, guanosine monophosphate, which enhances umami taste, was highest in Baekseon (0.7 mg/g). Baekseon was also calculated to have the highest umami taste concentration based on amino acid and nucleic acid contents (12.7 g/100 g). The results of this study serve as valuable basic data on the physicochemical characteristics of oyster mushroom cultivars grown in Korea.
        4,000원
        119.
        2023.09 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        This study compared research trends in universities general English program before and after the COVID-19 pandemic. After analyzing 248 articles from KCI using frequency analysis, centrality analysis, and topic modeling, this study found consistent keywords indicating a focus on learning objectives, effectiveness analysis, satisfaction surveys, and level-based learning before and after the COVID-19 pandemic. Centrality analysis revealed keywords like “teaching, research, analysis” before COVID-19 and “satisfaction, study, level, activity, effect” after COVID-19, indicating a shift towards learner satisfaction, level-based learning, and effectiveness analysis due to the transition to online learning. Topic modeling revealed shifts in research trends: Pre-COVID-19 focused on effective teaching methods, evaluation techniques, and cultural content, while Post-COVID-19 prioritized online teaching methods, web-based platforms, and selfdirected learning. Future research should address self-directed learning, attitudes and goal setting, closing learning gaps in online/blended learning, and developing effective online assessment tools and evaluation strategies. This study provides valuable insights and directions for further research in general English programs.
        5,700원
        120.
        2023.09 구독 인증기관 무료, 개인회원 유료
        이 글은 석성에서 토성으로 개축 시 양상을 설명하기 위해 작성된 것이며, 행주산성을 대 상으로 하였다. 이 산성은 삼국시대에 테뫼식 석축산성-석성 1-으로 축조된 이후 다양한 부 속시설이 설치되었다. 고려시대에는 토성-토성 1-으로 개축되었으며, 이후 정확한 시기는 알 수 없지만, 석성-석성 3-으로 개축되었음이 밝혀졌다. 행주산성의 석성 1은 덕양산과 서쪽 사면의 8~9부 능선을 두르는 테뫼식 석축산성으로 축성되었다. 외벽에는 1~2차례의 수축이 이루어졌으나 적극적인 생활면의 변화는 확인되 지 않는다. 이후 북서벽에 치 1이 가축되었다. 서벽 북쪽의 트렌치 토층을 분석하면 석성 1 외부를 단상으로 굴착한 부분과 외황이 매몰되고 일정 부분 대지가 조성되었다. 보축성벽과 치 2가 가축되면서 북동쪽 성우과 서벽 외부에는 비교적 넓은 평탄지가 조성 된다. 성 내부는 구지표를 절개한 후 1열의 내벽이 축조되었다. 이와 연동하여 생활면은 2차 례 정도 높아졌고, 각각의 상면에는 기와와 점토를 혼합하여 다졌다. 이후 남서벽에 석성 2 와 치 3이 축조되었으나 성 내부의 생활면 변화는 알 수 없다. 석성이 폐기된 이후 서쪽과 남쪽으로 확장된 포곡식의 토성이 축조되었다. 북동쪽 성우 의 성벽은 석성 1의 붕괴와 자연스럽게 연결되면서 마감된다. 이 부분의 남쪽은 토성벽이 보이지 않다가 동벽에서 토성 1이 확인되는데, 토성으로 개축된 이후에도 석성을 활용하였 음을 알 수 있다. 일정 기간이 지난 후 북동쪽 성우와 남동벽에 치가 가축된다. 기저부의 양 상으로 보아 토성 1과 공정상의 차이로 보기 어렵고, 당연히 생활면의 변화가 감지된다. 토 성 2가 축조되는 시점에는 생활면이 상당히 높아졌으며, 성 외부의 지형은 굴곡을 이루고 있었다. 이후에는 토성이 폐기된 이후 퇴적층 상부에 석성 3이 축조됨으로써 생활면의 변화 를 유추할 수 있다. 따라서 행주산성은 테뫼식 석성으로 축조된 이후 포곡식 토성, 마지막으로 석성으로 개 축되었다. 이에 연동하여 생활면은 지속해서 높아짐을 알 수 있다. 한편, 토성에 대한 기왕의 연구는 성벽을 축조한 이후 유지가 어려우므로 내ㆍ외피 토루 를 설치해야만 붕괴를 방지할 수 있다고 알려져 왔다. 하지만 토성 1의 성벽은 초축 당시 최 소 300㎝ 이상이었다. 내ㆍ외피 토루 없이 유지되었음이 밝혀졌으므로 토성에 대한 개념을 재검토해야 하는 자료를 확보하였다. 이 글의 대상인 행주산성 성벽의 구조와 구지표의 변 화는 다른 성곽 조사에도 적용할 수 있다고 생각한다. 따라서 성곽에 대한 조사를 진행할 경 우 성벽의 구조와 더불어 경관의 변천(성벽의 수·개축과 구지표의 변화 등)을 파악하는데, 중점을 두어야 할 것이다.
        6,400원