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Crystallographic Study on the Selectivity and Distribution of Sr2+ Ions Within Zeolite A In the Presence of Competing Na+ Ions in Aqueous Exchange Solution (Na+ 경쟁이온이 존재하는 수용액에서 Zeolite A 내 Sr2+ 이온의 선택성 및 분포에 관한 결정학적 연구)

  • kim, Hu Sik;Park, Jong Sam;Lim, Woo Taik
    • Korean Journal of Mineralogy and Petrology
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    • v.35 no.1
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    • pp.41-50
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    • 2022
  • To study the properties of Sr2+ exchange into zeolite A with increasing the molar concentration of Na+ in given exchange solution, four single crystals of fully dehydrated Sr2+- and Na+- exchanged zeolite A were prepared by the bath method using mixed ion-exchange solutions. The Sr(NO3)2:NaNO3 molar rations of the ion exchange solution were 1:1(crystal 1), 1:100(crystal 2), 1:250(crystal 3), and 1:500 (crystal 4), respectively, with a total concentration of 0.05 M. The single-crystals were then vacuum dehydration at 623 K and 1×10-4 Pa for 2 days. Their single-crystal structures were determined by single-crystal synchrotron X-ray diffraction techniques in the cubic space group Pm3-m, at 100(1) K, and were then refined to the final error indices of R1/wR2=0.047/0.146, 0.048/0.142, 0.036/0.128, and 0.040/0.156 for crystals 1, 2, 3, and 4, respectively. In crystals 1 and 2, the 6 Sr2+ ions are found at three different crystallographic sites. In crystal 3, 1 Sr2+ and 10 Na+ ions are found in large cavity and sodalite unit. In crystal 4, only 12 Na+ ions occupy three equipoints. The degree of Sr2+ ion-exchange decreased sharply from 100 to 16.7 to 0% as the initial Na+ concentration increase and the Sr2+ concentration decrease. In addition, the unit cell constant of the zeolite framework decreased with this lower level of Sr2+ exchange.

Comparison of Ultrasound Image Quality using Edge Enhancement Mask (경계면 강조 마스크를 이용한 초음파 영상 화질 비교)

  • Jung-Min, Son;Jun-Haeng, Lee
    • Journal of the Korean Society of Radiology
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    • v.17 no.1
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    • pp.157-165
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    • 2023
  • Ultrasound imaging uses sound waves of frequencies to cause physical actions such as reflection, absorption, refraction, and transmission at the edge between different tissues. Improvement is needed because there is a lot of noise due to the characteristics of the data generated from the ultrasound equipment, and it is difficult to grasp the shape of the tissue to be actually observed because the edge is vague. The edge enhancement method is used as a method to solve the case where the edge surface looks clumped due to a decrease in image quality. In this paper, as a method to strengthen the interface, the quality improvement was confirmed by strengthening the interface, which is the high-frequency part, in each image using an unsharpening mask and high boost. The mask filtering used for each image was evaluated by measuring PSNR and SNR. Abdominal, head, heart, liver, kidney, breast, and fetal images were obtained from Philips epiq5g and affiniti70g and Alpinion E-cube 15 ultrasound equipment. The program used to implement the algorithm was implemented with MATLAB R2022a of MathWorks. The unsharpening and high-boost mask array size was set to 3*3, and the laplacian filter, a spatial filter used to create outline-enhanced images, was applied equally to both masks. ImageJ program was used for quantitative evaluation of image quality. As a result of applying the mask filter to various ultrasound images, the subjective image quality showed that the overall contour lines of the image were clearly visible when unsharpening and high-boost mask were applied to the original image. When comparing the quantitative image quality, the image quality of the image to which the unsharpening mask and the high boost mask were applied was evaluated higher than that of the original image. In the portal vein, head, gallbladder, and kidney images, the SNR, PSNR, RMSE and MAE of the image to which the high-boost mask was applied were measured to be high. Conversely, for images of the heart, breast, and fetus, SNR, PSNR, RMSE and MAE values were measured as images with the unsharpening mask applied. It is thought that using the optimal mask according to the image will help to improve the image quality, and the contour information was provided to improve the image quality.

Synthesis and Structural Study of Extraframework ZrI6Tl119+ Cationic Cluster in Zeolite A (제올라이트 A 동공 내 비골격 ZrI6Tl119+ 양이온 클러스터의 합성과 구조 연구)

  • Hyeon Seung, Lim;Jong Sam, Park;Cheol Woong, Kim;Woo Taik, Lim
    • Korean Journal of Mineralogy and Petrology
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    • v.35 no.4
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    • pp.447-455
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    • 2022
  • Fully dehydrated Tl12-LTA (|Tl12|[Si12Al12O48]-LTA,Tl12-A) was treated with 6.0×103 Pa of ZrI4 (g) at 623 K for 72 hr under anhydrous conditions. The crystal structure of product, |Zr0.25I1.5Tl12|[Si12Al12O48]-LTA, was determined by single-crystal crystallography using synchrotron X-radiation in the cubic space group Pm3m (a = 12.337(2) Å). It was refined using all data to the final error index (for the 712 unique reflections for which Fo> 4σ(Fo) R1/wR2= 0.055/0.189. In this structure, octahedral ZrI62- ions center about 25% of the large cavities (Zr-I = 2.91(4) Å). Each coordinates to eight Tl+ ions and they are further bridged by Tl+ ions in the planes of 8-rings to form a cubic three-dimensional ZrI6Tl119+ cationic cluster. About 1.5 Tl+ ions per unit cell moved to deeper side of sodalite cavity after reaction with ZrI4(g). The remaining Tl+ ions occupy well-established cation positions near 6- and 8-rings.

A Study on the Uimul for Reproduction of Gyeongsang-Gamsa Doim Procession in the late Joseon Dynasty: Jeol, Wol, and Ilsan (조선후기 경상감사 도임행차 재현을 위한 의물 연구 : 절·월 및 일산을 중심으로)

  • Lee, Eunjoo;Kim, Migyung
    • 지역과문화
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    • v.7 no.2
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    • pp.133-154
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    • 2020
  • In this study, we reviewed the preparation process and the main Uimul involved in the procession of Gyeongsang Gamsa Doim in the late Joseon Dynasty. We reviewed the Yeongyeong- Ilgi, written by Cho, Jae-ho, and the Miam-Ilgicho, wtitten by Yoo Hee-chun. Those who had been appointed as a Gamsa by the Sammang System went through the Saeun and Sajo procedures to thank and say goodbye to the king before leaving for his assignment. The Gyoseo and Yuseo were usually received from the king at this time, but in some cases, they were received in the Seungjeongwon, or the Seori of Seungjeongwon brought them directly to the place where the Gamsa works. The Milbu with the Eoab was received along with the Yuseol, and the principle was to return the Milbu later. The procession of Gamsa is divided into the pre-and post-Gyoinsik procession and the Sunryeok procession. It was confirmed that the pre-Gyoinsik procession was made more compact than the post-Gyoinsik procession. In the study, we reviewed Ilsan, which is necessary for the officials' procession, and also examined the Gyoseo, Yuseo, Jeol·Wol, and Milbu received from the king. We also looked at the Gwan-in and Byeongb given by the former Gamsa at the the Gyoinsik. The Jeol, which means the command and the Wol, which means killing power, were given to the Gamsa. And unlike previous studies, it was confirmed that the Jeol was a perforated hexagon and and the Wol was a trident. Also, it was found that Ilsan is white, and there are two rows of Yuso on each of the six ribs of the umbrella. It is thought that the results of this study, which looked at the Doim process and Uimul by dividing the Gyeongsang-Gamsa Doim procession in the late Joseon Dynasty pre-and post-Gyoinsik, will be helpful in understanding the process of Gasmsa Doim. In addition, it is expected that it can be used as basic data for reproduction event of traditional culture related to Gwana, such as the reproduction of Gyeongsang-Gamsa Doim-Sunlyeok procession and Gyoinsik.

A Study on the Types of Dispute and its Solution through the Analysis on the Disputes Case of Franchise (프랜차이즈 분쟁사례 분석을 통한 분쟁의 유형과 해결에 관한 연구)

  • Kim, Kyu Won;Lee, Jae Han;Lim, Hyun Cheol
    • The Korean Journal of Franchise Management
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    • v.2 no.1
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    • pp.173-199
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    • 2011
  • A franchisee has to depend on the overall system, such as knowhow and management support, from a franchisor in the franchise system and the two parties do not start with the same position in economic or information power because the franchisor controls or supports through selling or management styles. For this, unfair trades the franchisor's over controlling and limiting the franchisee might occur and other side effects by the people who give the franchisee scam trades has negatively influenced on the development of franchise industry and national economy. So, the purpose of this study is preventing unfair trade for the franchisee from understanding the causes and problems of dispute between the franchisor and the franchisee focused on the dispute cases submitted the Korea Fair Trade Mediation Agency and seeking ways to secure the transparency of recruitment process and justice of franchise management process. The results of the case analysis are followed; first, affiliation contracts should run on the franchisor's exact public information statement and the surely understanding of the franchisee. Secondly, the franchisor needs to use their past experiences and investigated data for recruiting franchisees. Thirdly, in the case of making a contract with the franchisee, the franchisor has to make sure the business area by checking it with franchisee in person. Fourthly, the contracts are important in affiliation contracts, so enacting the possibility of disputes makes the disputes decreased. Fifthly, lots of investigation and interests are needed for protecting rights and interests between the franchisor and franchisee and preventing the disputes by catching the cause and more practical solutions of the disputes from the government.

Enhancing Science Self-efficacy and Science Intrinsic Motivation through Simulated Teaching-learning for Pre-service Teachers (탐구 기반 모의 수업 실연이 예비 교사들의 과학적 자기 효능감, 과학 내재 동기에 미치는 영향)

  • Lee, Hyundong
    • Journal of Korean Elementary Science Education
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    • v.42 no.4
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    • pp.560-576
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    • 2023
  • The purpose of this investigation is to: (1) to derive an improvement factor for inquiry-based simulated teaching-learning in pre-service teacher training programs, and pre-service teachers practice simulated teaching that reflect the improvement factor, (2) to analyze the difference in science intrinsic motivation according to science self-efficacy and inquiry-based simulated teaching-learning experience. To achieve these goals, we recruited five elementary and secondary teachers as experts to help us develop an improvement factor based on expert interviews. Subsequently, third-year pre-service teachers of a university of education participated in our analysis of differences in science intrinsic motivation, according to their level of science self-efficacy and experience with inquiry-based simulated teaching-learning. Our methodology involved applying the analytic hierarchy process to expert interviews to derive improvement factor for inquiry-based simulated teaching-learning, followed by a two-way ANOVA to identify significant differences in science intrinsic motivation between groups with varying levels of science self-efficacy. We also conducted post-analysis through MANOVA statements. The results of our study indicate that inquiry-based simulated teaching-learning can be improved through activities that foster digital literacy, ecological literacy, democratic citizenship, and scientific inquiry skills. Moreover, small group activities and student-centered teaching-learning approaches were found to be effective in developing core competencies and promoting science achievements. Specifically, pre-service teachers prepared a teaching-learning course plan and inquiry-based simulated teaching-learning in seventh-grade in the Earth and Space subject area. Pre-service teachers' science intrinsic motivation analyze significant differences in all levels of science self-efficacy before and after simulated teaching-learning and significant difference in the interaction effect between simulated teaching-learning and scientific self-efficacy. Particularly, group with low scientific self-efficacy, the difference in science intrinsic motivation according to simulated teaching-learning was most significant. Teachers' scientific self-efficacy and intrinsic motivation are needed to improve science achievement and affective domains of students in class. Therefore, this study contributes to suggest inquiry-based simulated teaching-learning reflecting school practices from the pre-service teacher curriculum.

A Study on the Effects of Retirement Expectations & Social Supports & Entrepreneurial Intention for Employees Engaged in Financial Business on the Preparation for their Old Age (금융업 종사자의 은퇴기대, 사회적 지지 및 창업의지가 노후준비에 미치는 영향에 관한 연구)

  • Kim, Hyong-Sok;Kang, Shin-Kee
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.17 no.1
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    • pp.251-265
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    • 2022
  • According to the 2019 statistics of the National Statistical Office, the population of old people over 65 is 7.69 million which consists of 14.9% of total population in Korea, and the world's fastest compressed-aging is being processed. Employees engaged in financial business as representative high-wage workers tend to choose voluntary retirement regardless of their business types, and rarely get a new job or establish their own business successfully. This study analyzes the effects of retirement expectations, social supports, and entrepreneurial intention for employees engaged in financial business, and the differences by individual characteristics on the preparation for their old age. The subjects include 280 people working at Seoul metropolitan and Daegu area. The data were analyzed with the SPSS Win Ver. 18.0 for frequency analysis, reliability analysis, factor analysis, regression analysis, etc. and the results of the study are as follows. First, the result of analyzing the effect of retirement expectations of employees engaged in financial business on the preparation for old age shows that the retirement expectations of the people who consider retirement is a new start meaningfully affect the financial and physical preparations for old age. Second, it is shown that family relations for employees engaged in financial business meaningfully affect the financial preparation, and family relations and friendship relations meaningfully affect the emotional and social preparations, despite social supports do not relevantly affect the financial preparation for old age. Third, it is also shown that the entrepreneurial intention of employees engaged in financial business does not relevantly affect the financial and physical preparations, but meaningfully affects the emotional and social preparations for old age. Fourth, the result of analyzing the effect of the individual characteristics of employees engaged in financial business on the preparation for their old age shows that age, marital status, and job grade do not relevantly affect, but the experience of entrepreneurship education more affects the preparation for old age than no-experience.

Anti-wrinkle effects of solvent fractions from Jubak on CCD-986sk (CCD-986sk 세포 내 주박 분획물의 항주름 효능)

  • Young-Ah Jang;Hyejeong Lee
    • Journal of the Korean Applied Science and Technology
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    • v.41 no.2
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    • pp.508-519
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    • 2024
  • In this study, in order to evaluate the possibility of using Jubak as a functional cosmetic material, evaluation of antioxidant activity according to fractions and anti-wrinkle efficacy in CCD-986sk cells, a human fibroblast, were conducted. As a result of confirming the antioxidant activity by measuring ABTS+ radical scavenging ability, Jubak's Ethyl Acetate fractions was found to be 75.5% at a concentration of 1,000 ㎍/ml, showing the highest antioxidant activity among the extraction solvents. The wrinkle improvement effect was confirmed by measuring the inhibitory activity of elastase and collagenase, and in both test results, Jubak's Ethyl Acetate fractions showed the highest efficacy at a concentration of 1,000 ㎍/ml. As a result of measuring the synthesis rate of pro-collagen type I in CCD-986sk cells induced by UVB, Jubak showed the highest efficacy in the order of Ethyl Acetate, Water, Acetonitrile, and Hexan fractions at the same concentration of 20 ㎍/ml. As a result of measuring the inhibition rate of MMP-1, a collagen degrading enzyme, all four solvent fractions showed an efficacy of more than 70% at 20 ㎍/ml. As a result of measuring the mRNA expression levels of pro-collagen type I, MMP-1, and MMP-3 in a real-time PCR experiment, the protein expression level of pro-collagen type I increased when treated with Jubak fractions compared to the UVB group alone. The mRNA expression levels of MMP-1 and MMP-3 were confirmed to be decreased, and Ethyl Acetate fractions was the most effective in improving wrinkles after the control group (EGCG). As a result, it was confirmed that the Ethyl Acetate fractions among Jubak's solvent fractions has an anti-wrinkle effect against photoaging caused by UVB stimulation, and is expected to be used as a natural material for cosmetics.

A Study on the Effectiveness of Government Start-up Support Project Satisfaction and Business Capabilities by Start-up Growth Stage (창업성장단계별 정부의 창업지원사업 만족도와 창업가의 사업화역량의 효과에 관한 연구)

  • Yoon, Bok-man;Jang, Young-hye
    • Journal of Venture Innovation
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    • v.7 no.3
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    • pp.65-84
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    • 2024
  • This study confirms the relative influence of satisfaction with the government's start-up support project at each growth stage of start-up companies and entrepreneurs' commercialization capabilities on start-up commitment. The start-up growth stage was divided into start-up stage, initial growth stage, stagnation stage, and high growth stage, and the government's start-up support project was divided into eight types(entrepreneurship education, mentoring/consulting, facility space, commercialization support, policy funds, sales channels/marketing/overseas expansion, R&D support, and start-up events/network) and satisfaction was evaluated. The data used was the results of the Daegu Creative Economy Innovation Center's survey on entrepreneurship conditions. As a result of the analysis, it was confirmed that the entrepreneur's commercialization capabilities are more effective in increasing the entrepreneur's commitment to starting a business than the satisfaction with the government's start-up support project. Additionally, it was confirmed that relatively important factors in entrepreneurship immersion differ depending on the start-up stage. During the start-up period, the government's start-up support project was found to be an important factor in increasing entrepreneurs' commitment to starting a business, but it was confirmed that the government's start-up support project had no effect on the start-up commitment after the start-up growth stage. In addition, this study confirmed the relatively important government start-up support projects by start-up growth stage and found that satisfaction with start-up facilities can increase start-up commitment during the start-up stage, and that start-up facilities and commercialization support are important during the early growth stage. And in the Death Valley stage, startup facilities, commercialization support, and policy funds were confirmed to be relatively important factors, and in the high growth stage, mentoring was confirmed to be an important factor in increasing entrepreneurship immersion. The results of this study not only contribute theoretically to building entrepreneurship theory, but also determine the size and effective support plan for the government's entrepreneurship support project for each growth stage of startup companies, and help organizations that operate entrepreneurship policy and institutional support and startup support programs. It will have a significant contribution to management measures.

Effect of Feeding Whole Crop Barley Silage- or Whole Crop Rye Silage based-TMR and Duration of TMR Feeding on Growth, Feed Cost and Meat Characteristics of Hanwoo Steers (청보리 사일리지 TMR 또는 청호밀 사일리지 TME 급여 및 급여기간이 거세 한우의 증체, 사료비 및 육질특성에 미치는 효과)

  • Jin, Guang Lin;Kim, Jong-Kyu;Qin, Wei-Ze;Jeong, Jun;Jang, Sun-Sik;Sohn, Yong-Suk;Choi, Chang-Won;Song, Man-Kang
    • Journal of Animal Science and Technology
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    • v.54 no.2
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    • pp.111-124
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    • 2012
  • Feeding trial was conducted with 80 Hanwoo steers (7.5 months of age, 204.4 kg body weight) for 680 days from growing period to late fattening period to examine the feeding value of whole crop barley silage TMR (BS-TMR) and whole crop rye silage TMR (RS-TMR) on body gain, feed cost, slaughter characteristics and quality characteristics of $longissimus$ $dorsi$ muscle. Dietary treatments were conventional separate feeding of concentrate and rice straw (control), feeding BS TMR up to middle fattening period and same diet as for control during late fattening period (BS-TMR I), feeding BS-TMR for whole experimental period (BS-TMR II), feeding RS TMR up to middle fattening period and same diet as for control during late fattening period (RS-TMR I) and RS TMR for whole experimental period (RS-TMR II). Sixteen castrated calves were assigned to each treatment (4 pens, 4 heads per pen). Pens in each treatment were randomly distributed. Feeding both BS silage TMR and RS silage TMR slightly increased body gain of Hanwoo steers at the stages of growing and early fattening, and increased (P<0.0001) at middle fattening compared to feeding control diet while control diet tended to increase body gain at late fattening stage compared to feeding BS-TMR I, BS-TMR II and RS-TMR I diets. Total body gain was slightly increased in Hanwoo steers fed both I and II for BS and RS TMR compared to that in control diet. Feed cost per kg gain per head was relatively low in the Hanwoo steers fed silage TMRs to that fed control diet. Carcass weight, back fat thickness and $longissimus$ $dorsi$ area of Hanwoo steers tended to increase but lowered (P<0.047) yield index by feeding silage TMRs. Feeding BS TMR slightly decreased marbling score but no difference was found in the number of head over grade 1 between diets. Control diet tended to improve yield grade compared to silage TMRs. Chemical composition, water holding capacity, drip loss, cooking loss and pH, color and fatty acid composition of $longissimus$ $dorsi$ were not affected by experimental diets and feeding duration of silage TMRs. Shear force, however, was increased (P<0.046) by silage TMRs without difference between them compared to control diet. Based on the results of the current study, BS TMR and RS TMR could improve body gain and reduce feed cost without deteriorating meat quality compared to separate feeding of concentrate and rice straw. Overall feeding value was similar between BS TMR and RS TMR.