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Optimization for Ammonia Decomposition over Ruthenium Alumina Catalyst Coated on Metallic Monolith Using Response Surface Methodology (반응표면분석법을 이용한 루테늄 알루미나 메탈모노리스 코팅촉매의 암모니아 분해 최적화)

  • Choi, Jae Hyung;Lee, Sung-Chan;Lee, Junhyeok;Kim, Gyeong-Min;Lim, Dong-Ha
    • Clean Technology
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    • v.28 no.3
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    • pp.218-226
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    • 2022
  • As a result of the recent social transformation towards a hydrogen economy and carbon-neutrality, the demands for hydrogen energy have been increasing rapidly worldwide. As such, eco-friendly hydrogen production technologies that do not produce carbon dioxide (CO2) emissions are being focused on. Among them, ammonia (NH3) is an economical hydrogen carrier that can easily produce hydrogen (H2). In this study, Ru/Al2O3 catalyst coated onmetallic monolith for hydrogen production from ammonia was prepared by a dip-coating method using a catalyst slurry mixture composed of Ru/Al2O3 catalyst, inorganic binder (alumina sol) and organic binder (methyl cellulose). At the optimized 1:1:0.1 weight ratio of catalyst/inorganic binder/organic binder, the amount of catalyst coated on the metallic monolith after one cycle coating was about 61.6 g L-1. The uniform thickness (about 42 ㎛) and crystal structure of the catalyst coated on the metallic monolith surface were confirmed through scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. Also, a numerical optimization regression equation for NH3 conversion according to the independent variables of reaction temperature (400-600 ℃) and gas hourly space velocity (1,000-5,000 h-1) was calculated by response surface methodology (RSM). This model indicated a determination coefficient (R2) of 0.991 and had statistically significant predictors. This regression model could contribute to the commercial process design of hydrogen production by ammonia decomposition.

Development and Validation of the Korean Implementation Fidelity Checklist of Tier 1 School-Wide Positive Behavior Support (KIFC-T1) (한국형 학교차원 긍정적 행동지원 1차 실행충실도 척도(KIFC-T1)의 개발과 타당화)

  • Nam, Dong Mi;Chang, Eun Jin;Won, Sung-Doo;Cho Blair, Kwang-Sun;Song, Wonyoung
    • Korean Journal of School Psychology
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    • v.17 no.3
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    • pp.401-419
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    • 2020
  • The purpose of this study was to validate the Korean Implementation Fidelity Checklist of Tier 1 School-Wide Positive Behavior Support (KIFC-T1) for use in the Korean educational system. Tier 1 support, which is universal supports, within a multi-tiered, school-wide positive behavior support (SWPBS) model, aims to provide support to and prevent problem behaviors among all students in a school. The initial KIFC-T1 consisted of 48 items and 11 factors and was developed based on a literature review. Its content was validated by experts. The validated KIFC-T1 was introduced to 185 special school teachers who had experience implementing SWPBS and who used the instrument to assess the degree to which their schools had implemented Tier 1 support. Based on their responses, the construct validity of the KIFC-T1 was examined using factor, item, and internal consistency reliability analyses. The concurrent validity of the tool was examined using the PBS Evaluation Tool, School Climate Questionnaire, School Discipline Practice Scale, and PBS Effectiveness Scale. The analyses revealed that KIFC-T1 had a stable five-factor structure with 35 items, had good reliability (Cronbach's α=.956, each factor's Cronbach's α=.834-.951), and its results were statistically significantly correlated with those of the PBS Evaluation Tool, School Discipline Practice Scale, and the PBS Effectiveness Scale. However the KIFC-T1's results were not statistically significantly correlated with the results of the School Climate Questionnaire. These results suggest that KIFC-T1 is a reliable and valid tool for assessing the fidelity of universal support implementations.

A Study of Life Safety Index Model based on AHP and Utilization of Service (AHP 기반의 생활안전지수 모델 및 서비스 활용방안 연구)

  • Oh, Hye-Su;Lee, Dong-Hoon;Jeong, Jong-Woon;Jang, Jae-Min;Yang, Sang-Woon
    • Journal of the Society of Disaster Information
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    • v.17 no.4
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    • pp.864-881
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    • 2021
  • Purpose: This study aims is to provide a total care solution preventing disaster based on Big Data and AI technology and to service safety considered by individual situations and various risk characteristics. The purpose is to suggest a method that customized comprehensive index services to prevent and respond to safety accidents for calculating the living safety index that quantitatively represent individual safety levels in relation to daily life safety. Method: In this study, we use method of mixing AHP(Analysis Hierarchy Process) and Likert Scale that extracted from consensus formation model of the expert group. We organize evaluation items that can evaluate life safety prevention services into risk indicators, vulnerability indicators, and prevention indicators. And We made up AHP hierarchical structure according to the AHP decision methodology and proposed a method to calculate relative weights between evaluation criteria through pairwise comparison of each level item. In addition, in consideration of the expansion of life safety prevention services in the future, the Likert scale is used instead of the AHP pair comparison and the weights between individual services are calculated. Result: We obtain result that is weights for life safety prevention services and reflected them in the individual risk index calculated through the artificial intelligence prediction model of life safety prevention services, so the comprehensive index was calculated. Conclusion: In order to apply the implemented model, a test environment consisting of a life safety prevention service app and platform was built, and the efficacy of the function was evaluated based on the user scenario. Through this, the life safety index presented in this study was confirmed to support the golden time for diagnosis, response and prevention of safety risks by comprehensively indication the user's current safety level.

A Study for Kinetics and Oxidation Reaction of Alcohols using (C10H8N2H)2Cr2O7 ((C10H8N2H)2Cr2O7를 이용한 알코올들의 산화반응과 반응속도에 관한 연구)

  • Park, Young-Cho;Kim, Soo-Jong
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.6
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    • pp.927-933
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    • 2022
  • We synthesized (C10H8N2H)2Cr2O7, The structure of the product was characterized with FT-IR(infrared) and elemental analysis. The oxidation of benzyl alcohol by (C10H8N2H)2Cr2O7 in organic solvents showed that the reactivity increased with the increase of the dielectric constant. The oxidation of alcohols was examined by (C10H8N2H)2Cr2O7 in DMF, acetone. As a resuit, (C10H8N2H)2Cr2O7 was found as efficicent oxidizing agent that converted benzyl alcohol, allyl alcohol, primary alcohol and secondary alcohols to the corresponding aldehydes or ketones(65%~95%). The selective oxidation of alcohols was also examined by (C10H8N2H)2Cr2O7 in DMF, acetone. (C10H8N2H)2Cr2O7 was selective oxidizing agent(15%~95%) of benzyl alcohol, allyl alcohol and primary alcohol in the presence of secondary ones. In the presence of DMF solvent with acidic catalyst such as H2SO4. (C10H8N2H)2Cr2O7 oxidized benzyl alcohol(H) and its derivatives. The Hammett reaction constant(ρ) was -0.69(308K). The observed experimental data were used to rationalize the hydride ion transfer in the rate determining step.

Development and Validation of the 'Food Safety and Health' Workbook for High School (고등학교 「식품안전과 건강」 워크북 개발 및 타당도 검증)

  • Park, Mi Jeong;Jung, Lan-Hee;Yu, Nan Sook;Choi, Seong-Youn
    • Journal of Korean Home Economics Education Association
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    • v.34 no.1
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    • pp.59-80
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    • 2022
  • The purpose of this study was to develop a workbook that can support the class and evaluation of the subject, 「Food safety and health」 and to verify its validity. The development direction of the workbook was set by analyzing the 「Food safety and health」 curriculum, dietary education materials, and previous studies related to the workbook, and the overall structure was designed by deriving the activity ideas for each area. Based on this, the draft was developed, and the draft went through several rounds of cross-review by the authors and the examination and revision by the Ministry of Food and Drug Safety, before the final edited version was developed. The workbook was finalized with corrections and enhancements based on the advice of 9 experts and 44 home economics teachers. The workbook consists of 4 areas: the 'food selection' area, with 10 learning topics and 36 lessons, the 'food poisoning and food management' area, with 10 learning topics and 36 lessons, the 'cooking' area, with 11 learning topics and 43 lessons, and the 'healthy eating' area, with 11 learning topics and 55 lessons, resulting in a total of 42 learning topics, 170 lessons. The workbook was designed to evenly cultivate practical problem-solving competency, self-reliance capacity, creative thinking capacity, and community capacity. In-depth inquiry-learning is conducted on the content, and the context is structured so that self-diagnosis can be made through evaluation. According to the validity test of the workbook, it was evaluated to be very appropriate for encouraging student-participatory classes and evaluations, and to create a class atmosphere that promotes inquiry by strengthening experiments and practices. In the current situation where the high school credit system is implemented and individual students' learning options are emphasized, the results of this study is expected to help expand the scope of home economics-based elective courses and contribute to realizing student-led classrooms with a focus on inquiry.

Automated Analyses of Ground-Penetrating Radar Images to Determine Spatial Distribution of Buried Cultural Heritage (매장 문화재 공간 분포 결정을 위한 지하투과레이더 영상 분석 자동화 기법 탐색)

  • Kwon, Moonhee;Kim, Seung-Sep
    • Economic and Environmental Geology
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    • v.55 no.5
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    • pp.551-561
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    • 2022
  • Geophysical exploration methods are very useful for generating high-resolution images of underground structures, and such methods can be applied to investigation of buried cultural properties and for determining their exact locations. In this study, image feature extraction and image segmentation methods were applied to automatically distinguish the structures of buried relics from the high-resolution ground-penetrating radar (GPR) images obtained at the center of Silla Kingdom, Gyeongju, South Korea. The major purpose for image feature extraction analyses is identifying the circular features from building remains and the linear features from ancient roads and fences. Feature extraction is implemented by applying the Canny edge detection and Hough transform algorithms. We applied the Hough transforms to the edge image resulted from the Canny algorithm in order to determine the locations the target features. However, the Hough transform requires different parameter settings for each survey sector. As for image segmentation, we applied the connected element labeling algorithm and object-based image analysis using Orfeo Toolbox (OTB) in QGIS. The connected components labeled image shows the signals associated with the target buried relics are effectively connected and labeled. However, we often find multiple labels are assigned to a single structure on the given GPR data. Object-based image analysis was conducted by using a Large-Scale Mean-Shift (LSMS) image segmentation. In this analysis, a vector layer containing pixel values for each segmented polygon was estimated first and then used to build a train-validation dataset by assigning the polygons to one class associated with the buried relics and another class for the background field. With the Random Forest Classifier, we find that the polygons on the LSMS image segmentation layer can be successfully classified into the polygons of the buried relics and those of the background. Thus, we propose that these automatic classification methods applied to the GPR images of buried cultural heritage in this study can be useful to obtain consistent analyses results for planning excavation processes.

A Comparative Study on the Characteristics of Cultural Heritage in China and Vietnam (중국과 베트남의 문화유산 특성 비교 연구)

  • Shin, Hyun-Sil;Jun, Da-Seul
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.40 no.2
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    • pp.34-43
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    • 2022
  • This study compared the characteristics of cultural heritage in China and Vietnam, which have developed in the relationship of mutual geopolitical and cultural influence in history, and the following conclusions were made. First, the definition of cultural heritage in China and Vietnam has similar meanings in both countries. In the case of cultural heritage classification, both countries introduced the legal concept of intangible cultural heritage through UNESCO, and have similarities in terms of intangible cultural heritage. Second, while China has separate laws for managing tangible and intangible cultural heritages, Vietnam integrally manages the two types of cultural heritages under a single law. Vietnam has a slower introduction of the concept of cultural heritage than China, but it shows high integration in terms of system. Third, cultural heritages in both China and Vietnam are graded, which is applied differently depending on the type of heritage. The designation method has a similarity in which the two countries have a vertical structure and pass through steps. By restoring the value of heritage and complementing integrity through such a step-by-step review, balanced development across the country is being sought through tourism to enjoy heritage and create economic effects. Fourth, it was confirmed that the cultural heritage management organization has a central government management agency in both countries, but in China, the authority of local governments is higher than that of Vietnam. In addition, unlike Vietnam, where tangible and intangible cultural heritage are managed by an integrated institution, China had a separate institution in charge of intangible cultural heritage. Fifth, China is establishing a conservation management policy focusing on sustainability that harmonizes the protection and utilization of heritage. Vietnam is making efforts to integrate the contents and spirit of the agreement into laws, programs, and projects related to cultural heritage, especially intangible heritage and economic and social as a whole. However, it is still dependent on the influence of international organizations. Sixth, China and Vietnam are now paying attention to intangible heritage recently introduced, breaking away from the cultural heritage protection policy centered on tangible heritage. In addition, they aim to unite the people through cultural heritage and achieve the nation's unified policy goals. The two countries need to use intangible heritage as an efficient means of preserving local communities or regions. A cultural heritage preservation network should be established for each subject that can integrate the components of intangible heritage into one unit to lay the foundation for the enjoyment of the people. This study has limitations as a research stage comparing the cultural heritage system and preservation management status in China and Vietnam, and the characteristic comparison of cultural heritage policies by type remains a future research task.

A Comparative Study on the Ways of Enjoying Xīsāishān Mountain, Scenic Site and Euisang(意象: Images) of it Shown on a Number of the Historic Korean and Chinese Literatures (한중 역대 문집에 나타난 명승(名勝) 서새산(西塞山) 향유방식과 의상(意象) 비교 고찰)

  • Park, So-Hyun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.40 no.2
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    • pp.24-33
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    • 2022
  • The travel notes and nature poems found in historic literary men's works can be considered historical records related to scenic sites. Such travel notes and nature poems are based on the writers' personal characters, experiences, learning and etc. Such works clearly show the characters of each literature, information of the related objects and the writers' thoughts of the objects. This study, thus, looked into Euisang on Xīsāishān Mountain that could be the origin of Eobusa(漁父詞) loved and sung by Korean historic literary men, and found that the Korean and Chinese literary men's thoughts were shown through their ways to enjoy Xīsāishān Mountain and their Euisang on the mountain, which was different between the Korean and Chinese literary men depending on the geographical locations described in their poems. In detail, the study results are: 1. Such difference of the ways to enjoy Xīsāishān Mountain, the scenic site described in historic Korean and Chinese literary men's work is broadly classified into the ways to enjoy the scenic site by seeing it in person and the ways to enjoy it under the mental structure of speculation. 2. Xīsāishān Mountain in Wuxing is the background of Yújiāzi(漁家子) of the painting Zhāngzhìhé, is boasting its distinguished beautiful nature, and is the place where the Confucian Study of Hú(湖學) was originated. It is also the place known of its warmhearted climate. Therefore, Euisang on Xīsāishān Mountain under such beautiful and warmhearted circumstance are realized as the complete freedom and seclusion in Taoism and the satisfaction with the given environment and position in Confucianism. 3. Xīsāishān Mountain in Wǔchāng is a military strategic point with rugged mountain terrain and scenery that has been a historic ferocious battlefield and related with the loyal civil servant Qū Yuán. The Euisang on Xīsāishān Mountain in Wǔchāng, therefore, represents the nature scenery of a rugged fortress and patriotism of Confucianism. 4. The Korean literary men's way to enjoy Xīsāishān Mountain is Shinyu(神遊: spiritual travel), so that their Euisang is formed according to the direction of the writer's values. Especially it is noted that Korean Euisang on Xīsāishān Mountain is originally based on the painting Zhāngzhìhé that shows the complete free mood of Taoism; and the Euisang on Xīsāishān Mountain that came from the mindful image by the poet monk Qíjǐ of Tang dynasty and Kim Si-seup appears with such Buddhist ways to seek the truth as SakGongIlYeo(色空一如: Being full is essentially as same as being vacant) and GyeonSeongSeongBul(見性成佛: Everybody can become Buddha by enlightenment).

Relationship between Planthoppers (Nilaparvata lugens and Sogatella furcifera) and Rice Diseases (멸구류(類)(벼멸구 및 흰등멸구)와 수도병해(水稻病害)의 복합발생피해(複合發生被害)에 관(關)한 연구(硏究))

  • LEE, S.C.;Matias, D.M.;Mew, T.W.;Sorino, J.S.;Heinrichs, E.A.
    • Korean journal of applied entomology
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    • v.24 no.2 s.63
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    • pp.65-70
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    • 1985
  • The locational preference of the brown planthopper (BPH) Nilaparvata lugens ($St{\aa}l$) and the whitebacked plant hopper (WBPH) Sogatella furcifera(Horvath) was studied on rice cultivars IR22 and IR36 as an integral part of subsequent research on insect-fungal pathogen relationships. The BPH was observed to stay consistently on the basal portion while the WBPH showed a general preference for the upper portion regardless of varieties, rice growth stages and insect population density levels. The habitat preference of both species (BPH and WBPH) was found not to be affected by the presence of the other species when both species are present on the same host plant Five rice cultivars with different reactions to BPH biotype 2 were used in the study on BPH-Rhizoctonia solani relationship: IR22 and TN1 (susceptible); Triveni and ASD7 (moderately resistant); and IR42 (resistant). Test plants were inoculated with R. solani (Kuhn) $3{\sim}4$days after insect infestation. Sheath blight disease severity/incidence was significantly higher in the treatment where BPH+R. solani were together than in the treatment with only the pathogen. Symptom expression of the disease in the BPH-pathogen combination was faster and mycelial growth was more profuse inducing the formation of more infection structures. Regardless of varietal reaction to BPH biotype 2, the degree of hopperburn was significantly higher in the combination of the two pests as compared with that of BPH alone. There could be a synergistic relationship between the insect pest and the pathogen indicated by a positive interaction between the two species.

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The Trend of Cigarette Design and Tobacco Flavor System Development

  • Wu, Jimmy Z.
    • Journal of the Korean Society of Tobacco Science
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    • v.24 no.1
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    • pp.67-73
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    • 2002
  • In light of addressing consumer health concern, coping with anti-tobacco movement, and promoting new product, tobacco industry is actively pursuing to make a new generation of cigarettes with low tar and nicotine deliveries, and less harmful substances. Low tar and low nicotine cigarettes increases their market shares dramatically world wide, especially in KT&G, multinational tobacco companies, EU countries, even in China regulated by CNTC to set up yearly target to lower tar and nicotine deliveries. On the other hand, to design a new cigarette with reduced harmful substances begins to gain speed. The "modified Hoffmann list" publishes thirty plus substances in tobacco leaf and main smoke stream, which is the prime suspect causing health problems. Various ways and means are developed to reduce such components including new tobacco breeds, new curing method, tobacco leaf treatment before processing, selected filtration system, innovated casing system to reduce free radicals, as well as some non conventional cigarette products. In TSRC held this year, the main topic is related to reduce tobacco specific nitrosamines in tobacco leaf. The new generation of cigarette is in the horizon. It still needs a lot help to produce commercial products with satisfied taste and aroma characters. The flavor industry is not regulated by many governments demanding which ingredients might or might not be for tobacco use. However, most of the cigarette companies self impose a list of ingredients to guide flavor suppliers to design flavors. Unfortunately, the number of ingredients in those lists is getting shorter every year. It is understandable that the health is not the only reason. Some cigarette companies are playing safe to protect the company from potential lawsuit, while others are just copying from their competitors. Moreover, it is obvious that it needs more assistance from casings and flavors to design new generation of cigarettes with missing certain flavor components in tobacco leaf and main smoke stream. These flavor components are either non-existed or at lower level at new form of cured tobacco leaf or filtered in the main smoke stream along with reduced harmful substances. The use of carbon filters and other selected filtration system poses another tough task for flavor system design. Specific flavor components are missing from the smoke analysis data, which brings a notion of "carbon taste" and "dryness" of mouth feel. It is ever more demanded by cigarette industry to flavor suppliers to produce flavors as body enhancer, tobacco notes, salivating agents, harshness reducer, and various of aromatic notes provided they are safe to use. Another trend is that water based flavor or flavor with reduced ethanol as solvent is gaining popularity. It is preferred by some cigarette companies that the flavor is compounded with all natural ingredients or all ingredients should he GMO free. The new generation of cigarettes demands many ways of new thinking process. It is also vital for tobacco industry. It reflects the real needs for the consumers that the cigarette product should be safe to use as well as bearing the taste and aroma characters smokers always enjoyed. An effective tobacco flavor system is definitely a part of the equation. The global trend of tobacco industry is like trends of any other industries lead by consumer needs, benefited with new technology availability, affected by the global economy, and subjected for various rules and regulations. Anti-tobacco organizations and media exceptionally scrutinize cigarette, as a legal commercial product. Cigarette is probably the most studied commercial product for its composition, structure, deliveries, effects, as well as its new developmental trend. Therefore, any new trend of cigarette development would be within these boundaries. This paper is trying to point out what it would be like for tobacco industry in the next few yews and what concerns the tobacco industry. It focuses mostly on the efforts to produce safer cigarettes. It is such a vital task for the tobacco industry and its affiliate industries such as cigarette papers, filters, flavors, and other materials. The facts and knowledge presented in this paper might be well known for the public. Some of the comments and predictions are very much personal opinion for a further discussion.