Journal of The Korean Association For Science Education
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v.42
no.1
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pp.19-32
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2022
The need for polar education was further emphasized, depending on the importance of the pole, which is the best place for climate change detection and prediction, and treasure trove of future technology and resources. Therefore, this study analyzed the general cognitive and affective characteristics of elementary school students' polar literacy, and in addition, analyzed the cognitive and affective characteristics according to the level of diversity about polar experience. The items developed for the study were revised through a pilot survey of 43 fifth graders. They consisted of questions about gender, polar experience, scientific literacy, polar knowledge, polar literacy skills, polar literacy beliefs, and polar literacy attitudes. The types of questions used are selectable, reliable, and Likert (4 points), for a total of 66 questions. The students who participated in the study were 323 fifth grade elementary students. The study found that students were more interested in the dramatic consequences of polar changes than the scientific causes and processes associated with it. This is confirmed through the fact that they are more interested in and familiar with polar creatures suffering from polar changes than understanding ice, which is the main feature of and the central mechanism of polar changes. Students also recognized the issue of polar climate change as a global issue other than their own. They believe that what happens in the Arctic and Antarctica will affect the whole world, but not significantly to himself and his community. The level of knowledge about polar region and the ability to analyze and infer were not significantly related to each other, and students with a higher level of diversity of experience about polar region had a better understanding of polar science and technology. In this research, it is meaningful to check the characteristics related to the students' polar region and to use it as a basic data to show the direction in which polar literacy education should proceed in the future.
Seolah, Back;YuJi, Jang;Junghwan, Lee;Joonhaeng, Lee;Jisun, Shin;Jongbin, Kim;Miran, Han;JongSoo, Kim
Journal of the korean academy of Pediatric Dentistry
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v.49
no.4
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pp.379-391
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2022
The current study aimed to compare the pH, solubility value, and ion release capability of premixed mineral trioxide aggregates (MTAs) versus conventional pulp capping materials before and after setting. The following materials were used: resin-modified calcium silicate cement (TheraCal LC®, TLC), resin-modified calcium hydroxide cement (Ultra-BlendTM plus, UBP), and 2 kinds of premixed MTA (Endocem MTA® premixed regular [EMPR] and Well-RootTM PT [WRP]). The specimens of each material were prepared before and after setting and were immersed in distilled water. The materials' pH and solubility value were assessed. Next, three kinds of ion (calcium, sulfide, and strontium) released by pulp capping materials were evaluated via inductively coupled plasma atomic emission spectrometry. In the after-setting group, the pH of TLC and UBP decreased. However, the pH of the premixed MTAs increased with time. TLC released a higher concentration of strontium ion compared with the other materials. Meanwhile, EMPR released a significantly high concentration of sulfide ion (p < 0.05). In the after-setting group, the 2 kinds of premixed MTAs released a significantly higher concentration of calcium ion compared with the other materials (p < 0.05). In the after-setting group, EMPR had a significantly low solubility value (p < 0.05). The Kruskal-Wallis test, followed by the Mann-Whitney U test with Bonferroni correction, was used in statistical analysis. In conclusion, resin-modified calcium silicate cement, modified calcium hydroxide cement, and the 2 kinds of premixed MTAs had an alkaline pH and low solubility value and they released various concentrations of ions after setting.
The hollow modular concrete block reinforced foundation method is one of the ground reinforcement foundation methods that uses hexagonal honeycomb-shaped concrete blocks with mixed crushed rock to reinforce soft grounds. It then forms an artificial layered ground that increases bearing capacity and reduces settlement. The hollow modular honeycomb-shaped concrete block is a geometrically economical, stable structure that distributes forces in a balanced way. However, the behavioral characteristics of hollow modular concrete block reinforced foundations are not yet fully understood. In this study, a bearing capacity test is performed to analyze the reinforcement effectiveness of the hollow modular concrete block through the laboratory model tests. From the load-settlement curve, punching shear failure occurs under the unfilled sand condition (A-1-N). However, the filled sand condition (A-1-F) shows a linear curve without yielding, confirming the reinforcement effect is three times higher than that of unreinforced ground. The bearing capacity equation is proposed for the parts that have contact pressure under concrete, vertical stress of hollow blocks, and the inner skin friction force from horizontal stress by confining effect based on the schematic diagram of confining effect inside a hollow modular concrete block. As a result of calculating the bearing capacity, the percentage of load distribution for contact force on the area of concrete is about 65%, vertical force on the area of hollow is 16.5% and inner skin friction force of area of the inner wall is about 18.5%. When the surcharge load is applied to the concrete part, the vertical stress occurs on the area of the hollow part by confining effect first. Then, in the filled sand in the hollow where the horizontal direction is constrained, the inner skin friction force occurs by the horizontal stress on the inner wall of the hollow modular concrete block. The inner skin friction force suppresses the punching of the concrete part and reduces contact pressure.
Recently, as word embedding has shown excellent performance in various tasks of deep learning-based natural language processing, researches on the advancement and application of word, sentence, and document embedding are being actively conducted. Among them, cross-language transfer, which enables semantic exchange between different languages, is growing simultaneously with the development of embedding models. Academia's interests in vector alignment are growing with the expectation that it can be applied to various embedding-based analysis. In particular, vector alignment is expected to be applied to mapping between specialized domains and generalized domains. In other words, it is expected that it will be possible to map the vocabulary of specialized fields such as R&D, medicine, and law into the space of the pre-trained language model learned with huge volume of general-purpose documents, or provide a clue for mapping vocabulary between mutually different specialized fields. However, since linear-based vector alignment which has been mainly studied in academia basically assumes statistical linearity, it tends to simplify the vector space. This essentially assumes that different types of vector spaces are geometrically similar, which yields a limitation that it causes inevitable distortion in the alignment process. To overcome this limitation, we propose a deep learning-based vector alignment methodology that effectively learns the nonlinearity of data. The proposed methodology consists of sequential learning of a skip-connected autoencoder and a regression model to align the specialized word embedding expressed in each space to the general embedding space. Finally, through the inference of the two trained models, the specialized vocabulary can be aligned in the general space. To verify the performance of the proposed methodology, an experiment was performed on a total of 77,578 documents in the field of 'health care' among national R&D tasks performed from 2011 to 2020. As a result, it was confirmed that the proposed methodology showed superior performance in terms of cosine similarity compared to the existing linear vector alignment.
Kim, Hun Hwan;Ha, Sang Eun;Park, Min Young;Jeong, Se Hyo;Bhagwan, Bhosale Pritam;Abuyaseer, Abusaliya;Kim, Jeong Ok;Ha, Yeong Lae;Kim, Gon Sup
Journal of Life Science
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v.32
no.6
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pp.447-454
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2022
In this study, we confirmed the effect of HK shiitake mushroom mycelium (HKSMM) on immune enhancement in Balb/c mice. Experimental animals were divided into five groups: negative control (NC), positive control (PC; 1,000 mg/100 g; AHCC), T1 (500 mg/100 g; HKSMM), T2 (1,000 mg/100 g; HKSMM), and T3 (2,000 mg/100 g; HKSMM), and dissection was performed at four and six weeks. COX-2 and iNOS concentrations were significantly lower in the six-week experimental group than in the control group, and the NO results were also similar. Results of the confirmation of the factors related to the NF-κB (p-p65 and p-IκBα) and MAPK (pERK, pJNK, and p38) signaling pathways revealed that the HKSMM-fed experimental group significantly decreased compared with the control group. A comparative analysis of the number and size of white pulp in the spleen tissue showed that those of the experimental group were significantly higher than those of the control group in a concentration-dependent manner. These results suggest that HKSMM has both immune-enhancing and anti-inflammatory effects in Balb/c mice, indicating that it can be used as a health functional food ingredient.
Ham, Hyeon Su;Kim, Yong Kyu;Park, Chi Myeon;Lee, Chul Ho;Kim, YoungSeok
Journal of Korean Tunnelling and Underground Space Association
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v.23
no.6
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pp.577-587
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2021
Room and Pillar method is an underground facility construction method that maximizes the strength of the in-situ ground. In order to secure the safety of the underground space, it is necessary to secure the safety of the room actually used in addition to the safety of pillar of the room and Pillar method. In this study, the evaluation method for the safety of the room and rock pillar in the room and pillar method was studied through numerical analysis. Numerical analysis was performed for a total of 125 cases using ground conditions, pillar width, and room width as parameters, and the results were derived. As for the safety factor of the pillar, it was confirmed that the safety factor increased when the strength of the ground increased, and it was confirmed that the increment in the safety factor decreased when the width of the pillar was widened. The room strain was evaluated by applying the Critical strain. As the width of the pillar became narrower, the Critical strain was higher, and as the width of the room became smaller, the Critical strain was smaller. As a result of the correlation analysis between the safety factor of the pillar and the room strain, it was possible to derive the upper limit of the room strain that can secure the standard safety factor of the pillar according to the width of the pillar. It is judged that the results derived from this study can be used as a guideline to secure the safety of the room when the actual design is performed in consideration of the ground conditions and room width.
Journal of the Korean Society of Floral Art and Design
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no.44
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pp.33-51
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2021
This thesis analyzes the formal characteristics of Dutch flower still life from the 17th century to the early 18th century and looks into the relevance with the Dutch art market from a macro perspective. The 17th Flower Still Life is to represent social hierarchy in that as the imported exotic, recherch items, the flowers were classified in the terms of their rarity and expensiveness. For this intriguing research, the subject is circumscribed to a vase of flowers, which is the quintessence of In the form of various Dutch Flower Still Life. Dutch society in the early 17th century was centered on the civilian class engaged in trade and commerce, which allowed them to purchase art works to show off their wealth, economic benefits and satisfaction of aesthetic tastes. Among them, the popularity of flower still life was related to the concentrated demand for rare flowers from the new continent. Accordingly, exact depiction and sense of the three dimensional manner were highly regarded in the early flower still life. For the tastes of the wealthy citizens who succeeded in business, the identity of flowers and the actual screen were considered as important. However, after the mid 17th century, economic growth in the Netherlands put an end, and the art market was also on a downward path. The demand class of flower still life has gotten farther away from the spirit of businessmen and has changed into city aristocrats who were stable rentiers. Their tastes laid emphasis on subjective sensibility, which meant that aristocratic, asymmetric, and dramatic chiaroscuro were preferred rather than being realistic. Furthermore, in the 18th century illusionistic realism was abandoned as an expression method of the planar characteristics and a new era in the floral still life was ushered with the reinforcement of decorative effect. From this perspective, it is not an exaggeration to say that romanticism, which is thought of as the beginning of Contemporary Art, originated from the aesthetic taste of Dutch civic culture.
Kim, Chulyoung;Choi, Duyeol;Lee, Donghyun;Khan, Falguni;Kwon, Gimyon;Ham, Eunhye;Park, Jungjoon;Kil, Eui-Joon;Kim, Yonggyun
Korean journal of applied entomology
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v.61
no.2
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pp.319-330
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2022
Andong is a place to culture the great amount of hot pepper (Capsicum annuum L.) in Korea. This study reports a yearly occurrence (March 31~October 25, 2021) of thrips infesting the hot pepper in Andong. Thrips caught to yellow sticky traps were diagnosed by morphological characters and showed two dominant species: Frankliniella occidentalis and F. intonsa. During this period, a total of 107,874 thrips were caught and included F. occidentalis at about 82%, F. intonsa at about 17%, and the other thrips at about 0.3%. There were two main peaks at May~June and at September~October, respectively, in which the total number of thrips was higher in the second peak and most were F. occidentalis. Interestinly, a low level of thrips occurred during July~August was observed and explained by their susceptibility to high temperatures. A laboratory experiment by exposing thrips to high temperatures showed that thrips were susceptible to temperatures higher than 35℃ and not tolerant to 45℃ for 1 h. Indeed, high temperatures higher than 45℃ were recorded in the greenhouses in Andong during July~August. F. occidentalis was more tolerant to the high temperatures than F. intonsa. On the other hand, the thrips showed the highest occurrence peak at July~August in hot pepper-culturing greenhouse in Kangwon, where the average temperatures were mostly lower than those of Andong and no high temperatures higher than 45℃ were recorded during July~August. A viral disease caused by tomato spotted wilt virus (TSWV) was observed in the hot peppers cultured in Andong greenhouses. Multiplex PCR was used to detect the virus along with identification of thrips. With a high record of about 30%, the virus-infected thrips were detected during all the monitoring period. The virulent thrips were identified to be only F. intonsa. These results suggest that F. occidentalis gives a direct damage especially during harvesting period with their high populations while F. intonsa gives indirect damage by transmitting TSWV.
Kim, JongSu;Choi, SeukCheun;Jeong, SooHwa;Mock, ChinSung;Kim, DooBoem
Clean Technology
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v.28
no.2
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pp.131-137
/
2022
The semiconductor process currently emits various by-products and unused gases. Emissions containing pollutants are generally classified into categories such as organic, acid, alkali, thermal, and cabinet exhaust. They are discharged after treatment in an atmospheric prevention facility suitable for each exhaust type. The main components of organic exhaust are volatile organic compounds (VOC), which is a generic term for oxygen-containing hydrocarbons, sulfur-containing hydrocarbons, and volatile hydrocarbons, while the main components of alkali exhaust include ammonia and tetramethylammonium hydroxide. The purpose of this study was to determine the combustion characteristics and analyze the NOX reduction rate by maintaining a direct combustion and temperature to process organic and alkaline exhaust gases simultaneously. Acetone, isopropyl alcohol (IPA), and propylene glycol methyl ether acetate (PGMEA) were used as VOCs and ammonia was used as an alkali exhaust material. Independent and VOC-ammonia mixture combustion tests were conducted for each material. The combustion tests for the VOCs confirmed that complete combustion occurred at an equivalence ratio of 1.4. In the ammonia combustion test, the NOX concentration decreased at a lower equivalence ratio. In the co-combustion of VOC and ammonia, NO was dominant in the NOX emission while NO2 was detected at approximately 10 ppm. Overall, the concentration of nitrogen oxide decreased due to the activation of the oxidation reaction as the reaction temperature increased. On the other hand, the concentration of carbon dioxide increased. Flameless combustion with an electric heat source achieved successful combustion of VOC and ammonia. This technology is expected to have advantages in cost and compactness compared to existing organic and alkaline treatment systems applied separately.
Gwangyang Port Marine Industry Cluster is the only marine industry cluster in Korea that is currently in operation, but despite the implementation of various revitalization policies since its opening, the occupancy rate has been low so far. Accordingly, this study aims to identify the constraints of the current system that hinder the inducement of tenant companies and to suggest revitalization measures. For this purpose, this study analyzed the current status of research and development(R&D) projects in the port, shipping and logistics sector, which is a core industry of the Gwangyang Port Marine Industry Cluster. And a survey was conducted on companies with potential to move in. As a result, the proportion of R&D in the core industry sectors is lower than in other sectors, and most of R&D projects are being carried out mainly by small and medium-sized enterprises. In addition, the low need for port facilities and low accessibility to Gwangyang Port were derived as constraints. Considering the results, this study suggests four revitalization measures to induce tenant companies as follows. First, it is necessary to expand the scope of core industries from the current shipping, ports, and logistics to the entire maritime and fisheries, so that companies performing R&D in the industry can move in. Second, the industry code currently specified as a qualification need to be revised to include both the industry of the enterprise carrying out R&D projects and the core industry. Therefore, this study suggests an expanded industry code list that can replace current list. Third, a transition of tenant recruitment system from the regular system(once or twice a year) to the occasional system is proposed so that companies can move in flexibly when demand arises. Finally, in order to overcome geographically low accessibility, technology development support projects specialized in R&D that prospective tenant companies actually need are needed rather than financial support.
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