• Title/Summary/Keyword: other

Search Result 143,345, Processing Time 0.144 seconds

Leaching Behavior of Vanadium and Possibility of Recovery of Valuable Metals from VTM Concentrate by Sulfuric Acid Leaching (바나듐함유 티탄철석 정광으로부터 황산 침출법에 의한 바나듐의 침출거동 및 유가금속의 회수가능성)

  • Joo, Sung-Ho;Shin, Dong Ju;Lee, Dongseok;Park, Jin-Tae;Jeon, Hoseok;Shin, Shun Myung
    • Resources Recycling
    • /
    • v.31 no.1
    • /
    • pp.65-77
    • /
    • 2022
  • A study was conducted in Korea on the leaching behavior and possibility of recovery of vanadium and other valuable metals from domestic vanadium titanomagnetite (VTM) by direct acid leaching. In this study, a VTM concentrate containing 0.8% V2O5 was used, and the ratio of magnetite to ilmenite was calculated as 1.9:1 by using the HSC program. The leaching behavior of vanadium from the VTM was similar to that of iron, and it was affected by the concentration of sulfuric acid and temperature. Further, titanium could be leached in the form of TiOSO4 at a temperature higher than 75℃. To improve the leaching efficiency of V, Fe, and Ti in VTM, reductive sulfuric acid and oxidative sulfuric acid leaching were performed. When Na2SO3 was used as a reducing agent, the leaching rate of vanadium was 80% of that in that case of leaching by sulfuric acid. Similarly, the leaching rate of titanium increased from 20% to 50%. When Na2S2O8 was used as an oxidation agent, most of the vanadium was leached, and the main residue found by XRD analysis was ilmenite. In studies on the possibility of recovering valuable metals, the selective extraction of metals is hardly achieved by solvent extraction from oxidation leaching solutions; however, in this study, Cyanex 923, a solvation extractant from reductive leaching solutions, could selectively extract Ti.

A Study on Evaluation Method for Structural Suitability of Constructed Wetlands in Dam Reservoirs as an Ecological Water Purification System (생태적 수질정화시설로서 댐 저수지 인공습지의 구조 적정성 평가방안)

  • Bahn, Gwon-Soo
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.50 no.2
    • /
    • pp.23-40
    • /
    • 2022
  • Many constructed wetlands have been installed in dam reservoirs nationwide for ecological purification of watershed pollutants, but aging and reduced efficiency are becoming issues. To improve the management of constructed wetlands, an objective evaluation of structural suitability is required. This study evaluated 39 constructed wetlands of 15 dams. First, through fogus group interview(FGI), survey analysis, and analytic hierarchy process(AHP), eight evaluation items in the physical and vegetative aspects were selected and the evaluation criteria applied with weights were prepared. Second, as a result of the structural suitability evaluation, the average score of the overall constructed wetlands was 80.8, with 10 sites rated as 'good grade(91~100)', 22 sites rated as 'normal grade(71~90)' and 7 sites rated as 'poor grade(70 or less)'. The average score of physical structure evaluation was 52.6, with 14 sites rated as 'good', 21 sites as 'normal' and 4 sites as 'poor'. The suitability of location was good level in most constructed wetlands, but the water supply system, depth of water, ratio of length-to-width, and slope of flow channel were evaluated as 'normal' or less in constructed wetlands of 50% or more. Therefore, it was found that overall improvement was necessary for stable flow supply and flow improvement in the constructed wetland. The average score of vegetative structure evaluation was 28.2, and about 84% of them were identified as 'normal' or lower. As a result of analyzing the Spearman's correlation coefficient between the physical structure evaluation score and the vegetation structure evaluation score, there was a significant correlation(r = 0.728, p < 0.001), and it was found that each evaluation factor also influences each other. As a result of the case review of 6 constructed wetlands, the appropriateness of the evaluation results was confirmed, and it was found that the location, flow rate supply, and type of wetland had a great influence on the efficiency and operation of the wetland. Through this study, it will be possible to derive structural weaknesses of constructed wetlands in dam reservoirs as a nature-based solution, to prepare types and practical alternatives for improved management of each constructed wetland in the future, and to contribute to enhancing various environmental functions.

Comparative Analysis of Mitochondrial Genomes of the Genus Sebastes (Scorpaeniformes, Sebastidae) Inhabiting the Middle East Sea, Korea (한국 동해 중부해역에 서식하는 볼락속(Sebastes) 어류의 미토콘드리아 유전체 비교분석)

  • Jang, Yo-Soon;Hwang, Sun Wan;Lee, Eun Kyung;Kim, Sung
    • Korean Journal of Ichthyology
    • /
    • v.33 no.4
    • /
    • pp.226-239
    • /
    • 2021
  • Sebastes minor, Sebastes trivittatus, Sebastes owstoni, and Sebastes steindachneri are indigenous fish species inhabiting the central part of the East Sea, Korea. In order to understand the molecular evolution of these four rockfishes, we sequenced the complete mitochondrial genomes (mitogenomes) of S. minor and S. trivittatus. To further analyze the phylogeny of Sebastes species, the mitogenomes of 16 rockfishes were comparatively investigated. The complete mitochondrial DNA (mtDNA) nucleotide sequences of S. minor and S. trivittatus were 16,408 bp and 16,409 bp in length, respectively. A total of 37 genes were found in mtDNA of S. minor and S. trivittatus, including 13 protein-coding genes, 2 ribosomal RNA genes, and 22 transfer RNA genes, which exhibited similar characters with other Sebastes species in the East Sea, Korea. In addition, we detected a conserved motif "ATGTA" in the control region of the four Sebastes species, but no tandem repeat units. Comparative analyses of the congeneric mitochondrial genomes were performed, which showed that control regions were more variable than the concatenated protein-coding genes. As a result of analysing phylogenetic relationships of four Sebastes species by using concatenated nucleotide sequences of 13 protein-coding genes, S. minor, S. trivittatus, S. owstoni and S. steindachneri were clustered into three clades. The phylogenetic tree exhibited that S. minor and S. steindachneri shared a closer relationship, whereas S. trivittatus and S. vulpes formed another distinct clade. Our results contribute to a better understanding of evolutionary patterns of Sebastes species inhabiting the middle East Sea, Korea.

A Study on the Management Method in Accordance with the Vegetation Structure of Geumgang Pine (Pinus densiflora) Forest in Sogwang-ri, Uljin (울진 소광리 금강소나무림 식생구조 특성에 따른 관리방안)

  • Kim, Dong-Wook;Han, Bong-Ho;Park, Seok-Cheol;Kim, Jong-Yup
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.50 no.1
    • /
    • pp.1-19
    • /
    • 2022
  • The Geumgang Pine (Pinus densiflora) Forest in Sogwang-ri, Uljin has traditionally been a pine tree protection area (prohibited forest) for timber production purposes, and is now designated and managed as a protected area for forest genetic resource conservation by the Korea Forest Service. This study, we analyzed topographical characteristics, existing vegetation, tree age, and plant community structure, and proposed a sustainable management method for the Geumgang Pine (Pinus densiflora) Forest in Sogwang-ri, Uljin for timber havesting purposes. The topographical characteristics of the target area were 36.7% ridges and 38.7% valleys; the ratio of ridges to valleys was similar, and the slopes formed 24.7% of the total area. The types of pine forest communities are divided into six types based on the progress of pine forest renewal, the competition with other species such as deciduous broadleaf trees, and the formation of layered structures. It has been confirmed that the age of the large-diameter pine trees (40~60cm in diameter) is approximately 60~70 years, which is relatively low. As a result of the analysis of the relative importance percentage and layered structure, differences depended on the progress of the pine forest renewal project, and not only the maintenance of the pine forest, but also the creation of a secondary growth forest, the density adjustment of pine trees, and the active management of competitive trees. The average basal area by the community was 12,642.1~25,424.4cm2 for the tree layer and 1.8~1,956.5cm2 for the low tree layer based on a quadrat of 400m2. The difference in the basal area appeared to depend on the size and number of trees forming the tree layer and the degree of pine forest renewal (the degree of time elapsed after thinning pine trees). The average number of species that appeared in each community was 8.7-20.3; there were many species located in valleys, and the type competes with deciduous broadleaf trees due to the lack of management. The diversity of species ranged from 0.6915-1.0942, and was evaluated as low compared to pine communities in central temperate zones. In this paper, we determined the management goals of Geumgang Pine (Pinus densiflora) Forest in Sogwang-ri, Uljin to produce timber with high economic value, and suggested efficient vegetation management for continuous afforestation, the establishment of a timber production system, and improvement of wood production as a management direction.

Analysis of Thermal Environment Modification Effects of Street Trees Depending on Planting Types and Street Directions in Summertime Using ENVI-Met Simulation (ENVI-Met 시뮬레이션을 통한 도로 방향별 가로수 식재 형태에 따른 여름철 열환경 개선 효과 분석)

  • Lim, Hyeonwoo;Jo, Sangman;Park, Sookuk
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.50 no.2
    • /
    • pp.1-22
    • /
    • 2022
  • The modification effects of street trees on outdoor thermal comfort in summertime according to tree planting types and road direction were analyzed using a computer simulation program, ENVI-met. With trees, the air temperature and wind speed decreased, and the relative humidity increased. In the case of mean radiant temperature (Tmrt) and human thermal sensation, physiological equivalent temperature (PET) and universal thermal climate index (UTCI), there was a decrease during the daytime. The greatest change among the meteorological factors by trees happened in Tmrt, and PET and UTCI showed similar patterns with Tmrt·The most effective tree planting type on thermal comfort modification was low tree height, wide tree crown, high leaf area index, and narrow planting interval (LWDN). Tmrt, PET and UTCI showed a large difference depending on shadow patterns of buildings and trees according to solar altitude and azimuth angles, and building locations. When the building shade areas increased, the thermal modification effect by trees decreased. In particular, results on the east and west sidewalks showed a large deviation over time. When applying the LWDN, the northwest, west and southwest sidewalks showed a significant reduction of 8.6-12.3℃ PET and 4.2-4.5℃ UTCI at 10:00, and the northeast, east and southeast sidewalks showed 8.1-11.8℃ PET and 4.4-5.0℃ UTCI at 16:00. On the other hand, when the least effective type (high tree height, narrow tree crown, low leaf area index, and wide planting interval) was applied, the maximum reduction was up to 1.8℃ PET and 0.9℃ UTCI on the eastern sidewalks, and up to 3.0℃ PET and 0.9℃ UTCI on the western ones. In addition, the difference in modification effects on Tmrt, PET and UTCI between the tree planting types was not significant when the tree effects were reduced by the effects of buildings. These results can be used as basic data to make the most appropriate street tree planting model for thermal comfort improvement in urban areas in summer.

A Study on the Educational Necessity and Activation Plan of Image Making Program for Life Care (라이프케어를 위한 이미지메이킹 프로그램 교육의 필요성과 활성화 방안)

  • Yoon, Hee
    • Journal of Korea Entertainment Industry Association
    • /
    • v.14 no.7
    • /
    • pp.429-437
    • /
    • 2020
  • This study is aimed at exploring the current state, necessity and activation of curriculum related to image making program in domestic colleges. To achieve this, an empirical survey was carried out to college students to provide basic data for the development of image making education program in the college curriculum as a measure to guide job interviews with them and improve interpersonal skills of employees-to-be. To achieve this, a survey was carried out to 400 college students in Gwangju and Jeonnam areas. The analysis was conducted to verify the collected data using SPSS v. 21.0 through the process of data coding and data cleaning. The results are as follows. First, the necessity of image making program curriculum showed that they needed the image making program in the college curriculum, the image making program curriculum to get a job and manage an image of employees-to-be after graduation, and other people's help to figure out the images objectively. Second, the educational importance of image making program showed that attitude (behavior) was the highest, followed by manners & greeting, look, speech, relationship, clothes, hairstyle, and makeup. In terms of the important educational factors of image making program, look was the highest, followed by makeup, hairstyle, attitude (behavior), relationship, speech, clothes, and manners & greeting, which look was the most important. Third, the educational influence of image making program showed that the influence on employment was the highest, followed by the influence on relationship, and the influence on life. Fourth, the educational activation of image making program showed that the appropriate educational time for image making program they want was from the second year. Education hours they want were once a week for one semester. And the curriculum they want was liberal arts or an optional course of liberal arts. In terms of image making program-related curriculum contents, manner & greeting was the highest, followed by makeup & coordination, job fair, education to acquire a skill qualification, and training for domestic companies, which their biggest wish was manner & greeting. And image making program leaders they want were major professors. In terms of image making program-related education, speech or voice was the highest, followed by education to analyze communication, education to analyze and practice matching hairstyles and makeup, Education on corporate interviews, and education on walking or posture correction, which their biggest wish was speech or voice and education to analyze communication.

The Direction of Physical Training for Actor in Post-Drama Era, "Empty" (포스트드라마 시대에 따른 배우의 몸 훈련의 방향성,'비우기(empty)')

  • Ra, Kyung-Min
    • Journal of Korea Entertainment Industry Association
    • /
    • v.14 no.8
    • /
    • pp.77-90
    • /
    • 2020
  • Today, the transition to the era of "post-drama" brought a change in the position of text, which was considered the center of the play, and the expansion of the role of actors. After entering the post-drama era, the actor no longer transforms himself into "delivering" the fixed meaning of text, but "producing" the valid meaning of "now, here" meeting the audience. In other words, actors in the post-drama era have expanded their roles as "performers" who can become the subject of narratives themselves and create various theatrical languages. Despite the expansion of the actor's role, verbal-centered actor training through text, which still forms the basis of acting education, does not satisfy the newly changing contemporary theatricality and creates a gap between education and the field. Therefore, the researcher argued that non-verbal-centered acting education needs to be discussed, and highlighted the actors' physical training on the "empty" side. The researchers first compare and analyze the characteristics of modern theater people's training methods from an "empty" perspective. Based on this, researchers about the meaning and direction of the training "empty". Furthermore, the study concludes with an emphasis on the direction of acting education in the post-drama era, which is free from language that can respond to stimuli and interact freely.

An Analysis of the Impact of Strategic Festival Planning on Festival Satisfaction and Urban Regeneration : Focusing on the Gimje Horizon Festival (전략적 축제기획이 축제만족과 도시재생에 미치는 영향 분석: 김제지평선축제를 중심으로)

  • Kim, Namhee
    • 지역과문화
    • /
    • v.7 no.1
    • /
    • pp.59-98
    • /
    • 2020
  • An empirical study utilizing data was performed with a variable called 'strategic planning' for festivals in order to look into the impact of a cultural tourism festival on urban regeneration. As a success factor of a festival, strategic festival planning was drawn up, and the following hypotheses were set: Seven strategic factors verified through an exploratory factor analysis will have a positive impact on festival satisfaction (festival success) and on urban regeneration, and festival satisfaction will have a positive impact on urban regeneration by having a mediating effect on it. For the analysis, the Gimje Horizon Festival was selected as it was considered as a typical case of urban regeneration through a festival, and the relationship between the festival and urban regeneration was understood by conducting a combined analysis of a quantitative analysis through a survey, a literature search, field investigations and in-depth interviews. The quantitative analysis indicates that strategic planning has a positive impact on festival satisfaction (festival success) and on urban regeneration and that festival satisfaction has a positive impact on urban regeneration. The same study result as the quantitative analysis result was obtained even through a qualitative analysis. This shows that the higher the path coefficient of strategic planning, the higher the path coefficient of festival satisfaction and urban generation and that with better strategic planning, the effects of festival satisfaction and urban regeneration are maximized. In other words, when planning and implementing a festival by actively incorporating the seven strategic planning factors which were suggested as festival success factors earlier in this study beginning from the stage of festival planning, it is likely to have a positive impact not only on the success of the festival but also on urban regeneration. This is an implication that gives a new alternative to software-based urban regeneration through festivals. It is meaningful to present the importance of festival planning and the direction of planning to maximize the effect of urban regeneration to festival planners and urban regeneration experts. This study is believed to serve as a momentum for people to take a new approach to studies on festivals and urban regeneration utilizing software in the future.

The Effect of Science Class Using Smart Devices on the Perceptions and Scientific Attitude of Middle School Gifted Students (스마트 기기를 활용한 과학 수업이 중학교 영재 학생의 인식 및 과학적 태도에 미치는 영향)

  • Kim, Eun-Ji;Kim, Hyun-Kyung
    • Journal of the Korean Chemical Society
    • /
    • v.66 no.4
    • /
    • pp.323-332
    • /
    • 2022
  • The purpose of this study is to investigate the effects of science classes using smart devices that combine augmented reality (AR) and virtual reality (VR) on the scientific attitude of middle school gifted students. In addition, it is intended to find out the perception of science classes using these smart devices. In addition to actual experiments, a science class program that allows students to experience science experiments virtually using AR and VR was applied to 15 middle school gifted students. Before and after the application of the program, the questionnaire is to investigate the interest in scientific classes, the attitude toward science exploration, and the professional interest in science, and the recognition of classes that combine AR and VR. In addition, through in-depth interviews, the perceptions of gifted students was accurately investigated. As a result of this study, the content of science classes and instructors showed high class satisfaction, but the smart devices and applications used during the science classes showed lower class satisfaction than others. As a result of comparing and analyzing the pre-post of gifted students, interest in science class, attitude toward science inquiry, and professional interest in science increased significantly among the sub-areas of the scientific attitude test. As a result of analyzing free responses and indepth interviews, gifted students responded with the advantage that classes using smart devices that combine AR and VR can be tested quickly and safely for a short time compared to actual experiments. On the other hand, they responded with low completeness of the application and dizziness when operating virtual reality. Based on this, implications for the development of applications and instructional programs using advanced technologies that can experience realistically limited scientific experiments such as experimental preparation, class time, and risk factors were obtained.

The Effect and Disturbance Factors of Practical-Based Teacher Education Program for the Development of TPACK in Pre-service Chemistry Teachers (예비화학교사의 TPACK 발달을 위한 실천기반 교사교육 프로그램의 효과 및 방해 요인 분석)

  • Jung, Mi Sun;Paik, Seoung-Hey
    • Journal of the Korean Chemical Society
    • /
    • v.66 no.4
    • /
    • pp.305-322
    • /
    • 2022
  • In this study, a practice-based teacher education program was developed and applied to improve the TPACK of pre-service chemistry teachers. Also the program effect and obstacles were confirmed by measuring the development of TPACK. The participants of this study were 20 pre-service chemistry teachers of 3rd grade and 2 pre-service chemistry teachers of 4th grade who took chemistry education courses at K University located in Chungcheongbuk Province. The developed teacher education program consisted of four stages: preparation, rehearsal, practice, and reflection. The feedbacks from researchers and colleagues pre-service teachers were provided in preparation, rehearsal, and reflection stages. As a result of the study, the program of this study did not show an educational effect in the "constructive learning activities" of preservice teachers, but it was found to have an educational effect in "problem solving". In other words, in "constructive learning activity", most pre-service teachers were at 0 level before and after the program. The pre-service teachers designed the class to unilaterally provide technology to simply use it as a tool to explain subject content or revise misconceptions, and learners can passively acquire knowledge. However, in the case of "problem solving", the pre-service teachers who were at level 0 before the educational program changed to level 1. Before the program, the pre-service teachers designed classes to solve problems by memory without using technology, but after the program they planned classes that provides opportunities to approach and solve various problems through the technology presented by the teacher. However, there were not many pre-service teachers corresponding to level 2, which constitutes voluntary learning in which learners use technology to solve various problems while selecting and variously manipulating technology. In addition, as obstacles to the TPACK development of pre-service chemistry teachers, there were external factors such as lack of classroom support environment for TPACK implementation, lack of time for education planning, and inadequate technology competency. And there were internal factors such as perspectives of traditional education and negative attitude toward technology. In particular, the proportion of pre-service teachers who preceived inappropriate technical competency as an external obstacles of TPACK development was high. Therefore, it was necessary to develop an education program corresponding to type 2 or type 3 that enables TPACK development through TK for pre-service teachers.