• Title/Summary/Keyword: 속도 유지

Search Result 3,943, Processing Time 0.035 seconds

A Study on the Conditions of Natural Damage of Undesignated Cultural Heritages and the Plans to Reduce Damage through Vegetation Management - With Emphasis on Samcheonsaji Temple Site on Mt. Bukhansan - (비지정 문화유적의 훼손현황과 식생관리를 통한 저감방안 연구 -북한산 삼천사지를 사례로-)

  • Hong, Hee-taek;Kim, Hyeon-beom;Lee, Mun-haeng
    • Korean Journal of Heritage: History & Science
    • /
    • v.46 no.3
    • /
    • pp.114-133
    • /
    • 2013
  • This study aims to identify the natural damage of the Samcheonsaji Temple Site in Bukhansan National Park and to suggest the plans to minimize damage for the remains. The types of natural damage are classified into direct vegetation damage, indirect topographical damage, and artificial damage. The most popular causes of damage to temple sites include the roots of trees as direct vegetation damage and the soil erosion by rain or stream as topographical damage. Direct vegetation damage includes burial remains damaged by the root of trees and vines, but it is often observed that some trees have contributed to protection against collapse. Indirect topographical changes have damaged the ruins by soil erosion caused by floods or typhoons. Vegetation changes due to topographical reasons have also caused damage. Artificial reasons of damage include forestry operations and compaction by hikers. Based on the analysis of the findings, the following could be suggested as plans to resolve these problems: 1. Natural damage occurs slowly due to negligence. Therefore, it could be reduced by forestry improvement, including forest density control through thinning, planting to prevent landslides, maintaining grasslands nearby. 2. Deciduous broadleaf trees can be planted to reduce soil erosion by rainfall. It is necessary to maintain the density of forests at around $0.02{\sim}0.18trees/m^2$. 3. It would be good to grow Quercus spp and Carpinus spp or weaken the community of Robinia pseudoacacia and Pueraria lobata which disturb the ecosystem. Samcheonsaji Temple Site is located in Mt. Bukhan National Park that is a publicly owned property. Therefore, it is constantly maintained for natural preservation and vegetation management could be considered for the preservation of historical remains.

Selective Algicidal Effects of a Newly Developed GreenTD against Red Tide Harmful Alga (GreenTD 물질을 이용한 유해 적조 발생 종의 선택적 살조능 평가)

  • Lee, Minji;Shin, Juyong;Kim, Jin Ho;Lim, Young Kyun;Cho, Hoon;Baek, Seung Ho
    • Korean Journal of Environmental Biology
    • /
    • v.36 no.3
    • /
    • pp.359-369
    • /
    • 2018
  • Harmful algal blooms (HABs) are a serious problem for public health and fisheries industries, thus there exists a need to investigate the possible ways for effective control of HABs. In the present study, we investigated the algicidal effects of a newly developed GreenTD against the HABs (Chattonella marina, Heterosigma akashiwo, Cochlodinium polykriokides, and Heterocapsa circularisquama) and non-HABs (Chaetoceros simplex, Skeletonema sp. and Tetraselmis sp.), which is focused on the different population density and concentration gradients of algicidal substances. The time series viability of target alga was assessed based on the activity of Chl. a photosynthetic efficiency in terms of $F_v/F_m$, and in vivo fluorescence (FSU). Effective control of Raphidophyta, C. marina and H. akashiwo was achieved at a GreenTD concentration of $0.5{\mu}gL^{-1}$ and $0.2{\mu}gL^{-1}$, respectively, and regrowth of both the species was not observed even after 14 days. The inhibitory ratio of the dinoflagellate, C. polykriokides was more than 80% at $0.2{\mu}gL^{-1}$ of GreenTD. H. circularisquama was constantly affected in the presence of $0.2{\mu}gL^{-1}$ of GreenTD in the high- and low-population density experimental groups. On the other hand, diatoms, C. simplex, and Skeletonema sp. were not significantly affected even in the presence of $0.2{\mu}gL^{-1}$ of GreenTD and exhibited re-growth activity with the passage of incubation time. In particular, green alga Tetraselmis sp. remained unaffected even in the presence of the highest concentration of GreenTD ($1.0{\mu}gL^{-1}$), implying that non-HABs were not greatly influenced by the algicidal substances. As a result, the algicidal activity of GreenTD on the harmful and nonharmful algae was as follows: raphidophyte>dinoflagellates>diatoms>green alga. Consequently, our results indicate that inoculation of GreenTD substances into natural blooms at a threshold concentration ($0.2{\mu}gL^{-1}$) can maximize the algicidal activity against HABs species. If we consider the dilution and diffusion rate in the field application, it is hypothesized that GreenTD will demonstrate economic efficiency, thus leading to effective control against the target HABs in the closed bay.

Effects of Initiation and Perceived Similarity on the Evaluation of Online Communities (온라인 커뮤니티 속 가입절차 및 지각된 유사성에 따른 평가의 차이)

  • Yoo, Jihyun;Kang, Hyunmin;Han, Kwanghee
    • Science of Emotion and Sensibility
    • /
    • v.21 no.4
    • /
    • pp.25-36
    • /
    • 2018
  • Nowadays, it is hard to imagine one's life without smart phones or the internet. Furthermore, not only do people form groups offline, but also online. Based on the cognitive dissonance theory, there have been many studies about how an offline group's initiation affects attitudes toward the group. However, there has not been a study about how an online group's initiation can affect attitudes toward the group. Therefore, this study aims to find out how cognitive dissonance aroused by initiation affects the attitudes toward the online community, which represents groups that are formed online. In addition, this study examined how perceived similarity affects changes in attitude aroused by cognitive dissonance. Participants were assigned to a group in three ways as follows: without a registration process, with a simple registration process, and/or with a complex registration process. Perceived similarity was calculated by the difference between the current body mass index (BMI) and the target BMI of the participant. Attitudes toward the online group were measured by perceived source credibility, perceived information quality, satisfaction, information usefulness, and continuance intention. Contrary to the cognitive dissonance theory, the results showed that when applied to offline social groups, there were conflicting results. There were cases where there was no difference in the evaluation between initiation conditions. However, other cases showed that groups with the most complex registration process were found to have the worst evaluation. People were more favorable toward the group when the perceived similarity was larger. Interestingly, people who had higher perceived similarity had more positive attitudes toward the groups that had been assigned with a registration process compared to the group formed without a registration process. Conversely, people with lower perceived similarity had more positive attitudes toward the group when there was no initiation process. Online communities may use the results of this study to design more suitable registration processes for their communities.

A Study on the Concept and User Perception of Smart Park - Focused on the IoT See Park Users in Daegu City - (스마트공원 개념 정립 및 공원 이용자 인식에 관한 연구 - 대구 IoT See 시범사업 공원 이용자를 대상으로 -)

  • Lee, Hyung-Sook;Min, Byoung-Wook;Yang, Tae-Jin;Eum, Jeong-Hee;Kim, Kwon;Lee, Ju-Yong
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.47 no.5
    • /
    • pp.41-48
    • /
    • 2019
  • Our daily lives are changing at a rapid pace and the concept of smart city is spreading, as the information communication technologies apply to various fields. However, efforts to prepare for changes in society due to technological evolution are insufficient in the field of landscape architecture. The purposes of this study are to explore the concept of smart parks, to investigate how smart technology has been applied to parks, and to identify the users' perception and satisfaction on smart park services. To this end, we conducted literature review, focus group interviews with experts, and a questionnaire survey with 180 users of the IoT See pilot smart park in Daegu. Smart parks can, as a result, be defined as sustainable parks that improve users' experience in parks and solve social and environmental problems faced by utilizing various high technology. Smart technologies introduced at the park so far have been mostly focused on safety and environmental areas, including AI CCTV, smart street lamp, and fine dust warning devices. The results of survey showed that not many users were aware of the smart services the park provided due to the lack of public communication as well as the nature of maintenance-oriented smart services. The survey also found that AR services for the education of historic parks were the least utilized, while solar power benches and WiFi service were most preferred by the park users. In conclusion, smart technologies need to be integrated with diverse park contents more centered user needs, providing services to enhance safety and environmental management in order to develop user-oriented smart parks.

Current status, perception and practicability of restaurant staffs related to reducing sodium use in Seongnam, Korea (성남 지역 외식업소의 나트륨 저감화 현황과 종사자의 저감화 실행에 대한 인식 및 실천용이도)

  • Ahn, So-Hyun;Kwon, Jong Sook;Kim, Kyungmin;Lee, Yoonna;Kim, Hye-Kyeong
    • Journal of Nutrition and Health
    • /
    • v.52 no.5
    • /
    • pp.475-487
    • /
    • 2019
  • Purpose: With the increase of going out to eat, reducing the sodium in restaurant foods has a crucial impact on reducing sodium intake. This study aimed to assess the current status and perceptions of restaurant staffs related to reducing sodium use in restaurants. Methods: Restaurant managers and chefs (n = 312) in Seongnam area completed a questionnaire on the current status related to sodium use, the barriers to practice for reducing sodium use, support needs, and the practicability of methods for reducing sodium use in restaurants. Results: The percentage of restaurants in the preaction stage (including the precontemplation, contemplation, and preparation stages) for reducing sodium use was 79.7%. Logistic regression analysis showed that measuring salinity while cooking was associated with measuring seasoning (OR, 4.761; 95% CI, 2.325 ~ 9.751), action/maintenance stages of behavior change (OR, 2.829; 95% CI, 1.449 ~ 5.525) and providing salinity information of restaurant foods (OR, 6.314; 95% CI, 2.964 ~ 13.45). Maintaining taste and hindering the cooking process were the main barriers to reduce sodium use. The total practicability of actions for reducing sodium was higher in staffs who worked in restaurants that measured seasoning and salinity while cooking (p < 0.05 and p < 0.01, respectively). The hardest item to practice was 'purchase foods after comparing sodium content in the nutrition labeling'. 'Avoid serving salt-fermented foods as side dishes', 'serve small portions of kimchi and less salty kimchi', and 'put up promotional materials for reducing sodium intake' were selected as easy items to perform. The majority (82%) was willing to reduce sodium in restaurant foods under the support of local government and they desired the promotion of participating restaurants and education on cooking skills to reduce sodium. Conclusion: Measuring seasoning and salinity while cooking is a meaningful practice that is associated with stages of behavior change and the practicability of actions for reducing sodium. It is necessary to provide support and education with a gradual approach to staffs for reducing sodium in restaurant foods.

Dynamic Changes of Urban Spatial Structure in Seoul: Focusing on a Relative Office Price Gradient (오피스 가격경사계수를 이용한 서울시 도시공간구조 변화 분석)

  • Ryu, Kang Min;Song, Ki Wook
    • Land and Housing Review
    • /
    • v.12 no.3
    • /
    • pp.11-26
    • /
    • 2021
  • With the increasing demand for office space, there have been questions on how office rent distribution produces a change in the urban spatial structure in Seoul. The purpose of this paper is to investigate a relative price gradient and to present a time-series model that can quantitatively explain the dynamic changes in the urban spatial structure. The analysis was dealt with office rent above 3,306 m2 for the past 10 years from 1Q 2010 to 4Q 2019 within Seoul. A modified repeat sales model was employed. The main findings are briefly summarized as follows. First, according to the estimates of the office price gradient in the three major urban centers of Seoul, the CBD remained at a certain level with little change, while those in the GBD and the YBD continued to increase. This result reveals that the urban form of Seoul has shifted from monocentric to polycentric. This shows that the spatial distribution of companies has gradually accelerated decentralized concentration implying that the business networks have become significant. Second, contrary to small and medium-sized office buildings that have undertaken no change in the gradient, large office buildings have seen an increase in the gradient. The relative price gradients in small and medium-sized buildings were inversely proportional among the CBD, the GBD, and the YBD, implying their heterogeneous submarkets by office rent movements. Presumably, those differences in the submarkets were attributed to investment attraction, industrial competition, and the credit and preference of tenants. The findings are consistent with the hierarchical system identified in the Seoul 2030 Plan as well as the literature about Seoul's urban form. This research claims that the proposed method, based on the modified repeat sales model, is useful in understanding temporal dynamic changes. Moreover, the findings can provide implications for urban growth strategies under rapidly changing market conditions.

Vegetation Structure and Growth Environmet of Diabelia spathulata (Siebold & Zucc.) Landrein Population in Mt. Cheonseong, Korea (천성산 주걱댕강나무 개체군의 식생구조와 생육환경)

  • Yi, Myung Hoon;Yoo, Sung Tae;Jang, Jeong Gul
    • Korean Journal of Plant Resources
    • /
    • v.34 no.4
    • /
    • pp.346-361
    • /
    • 2021
  • The range of D. spathulata identified in this survey was between N 35° 24' 58" ~ N 35° 26' 35", E 129° 05' 43" ~ E 129° 07' 04". It is located at an altitude of 98~592 m. The soil pH was strongly acidic in the range of 4.2~4.9, with a canopy openness of 18.56% and a chlorophyll index of 36.74 ± 2.80. As a result of the TWINSPAN analysis, 20 plots of 100 m2 each were divided in 4 communities: Pinus densiflora community, Quercus monglica-Diabelia spathulata community, Quercus serrata-Diabelia spathulata community and Carpinus tschonoskii subassociation. The result of species diversity was 0.7615, and evenness and dominance were found to be 0.6077 and 0.3923, respectively. The height of D. spathulata is up to 3.4 m, and the average height is 1.1 m, with most of the species distributed as shrubbery and herbaceous. The average population density of the 20 plots was 1.635 individuals/m2, the height range of flowering was 1.0 ~ 1.8 (aver. 1.39 m) and the rate of flowering was 27.37%. It's propagation pattern was mainly formed by extending the rhizome to the side, creating a colony of ground stems.

Exploring Science Teacher Agency as Agent of Change: The Case of Distance Learning Practice Due to COVID-19 (변화의 주체로서 과학 교사의 행위주체성 탐색 -COVID-19에 따른 원격 수업 실행 사례를 중심으로-)

  • Lee, Hyekeoung;Kim, Heui-Baik
    • Journal of The Korean Association For Science Education
    • /
    • v.41 no.3
    • /
    • pp.237-250
    • /
    • 2021
  • Teachers play a key role in designing a students' learning experience. Teachers are asked to interpret the context in which they are located and to adjust their practice to fit circumstantial needs based on their teacher agency. In this study, we explore the emergence of teacher agency in distance learning caused by COVID-19 and we analyze factors shaping the teacher agency. For this purpose, we interviewed six secondary science teachers who practiced distance learning in 2020. Semi-constructed interviews and their artifacts were collected and analyzed. This study shows that teacher agency is captured when they respond to circumstantial change and modify their practice to achieve their professional purpose or adjust their practice in space for maneuvering or keep their practice consistent. This study also analyzes the factors that affect the emergence of teacher agency in two dimensions. One is individual and the other is contextual. In the individual dimension, educational values shaped by his/her experiences and short/long-term goals for the future support the emergence of teacher agency. In the contextual dimension, there are collaborative and flexible culture shared by the community, co-operation within the teacher community, and material support. On the other hand, in the individual dimension, the teachers' sense of their role, and no reflection for own practice constrain the emergence of teacher agency, and in the contextual dimension, performativity discourse and strong requirement without guidance constrain the emergence of teacher agency. We suggest an effective lens for establishing a strategy that support teachers' professional practice and the emergence of teacher agency.

Predicting Healthy Lifestyle Patterns in Older Community Dwelling Adults: A Latent Profile Analysis (잠재프로파일 분석을 활용한 한국 노인 라이프스타일 유형화와 영향요인 분석)

  • Park, Kang-Hyun;Yang, Min Ah;Won, Kyung-A;Park, Ji-Hyuk
    • Therapeutic Science for Rehabilitation
    • /
    • v.10 no.2
    • /
    • pp.75-93
    • /
    • 2021
  • Objective : The aim of this study was to identify subgroups of older adults with respect to their lifestyle patterns and examine the characteristics of each subgroup in order to provide a basic evidence for improving the health and quality of life. Methods : This cross-sectional study was conducted in South Korea. Community-dwelling older adults (n=184) above the age of 65 years were surveyed from April 2019 to May 2019. This study used latent profile analysis to examine the subgroups. Chi-squared (χ2) and multinomial logistic regression measures were then used to analyze individual characteristics and influencing factors. Results : The pattern of physical activity which is one of the lifestyle domains in elderly was categorized into three types: 'passive exercise type (31.1%)', 'low intensity exercise type (54.5%)', and 'balanced exercise type(14.5%)'. Activity participation was divided into three patterns: 'inactive type (12%)', 'self-management type (61%)', and 'balanced activity participation type (27%)'. In terms of nutrition, there were only two groups: 'overall malnutrition type (13.5%)' and 'balanced nutrition type (86.5%)'. Furthermore, as a result of the multinomial logistic regression analysis to understand the effects of lifestyle types on the health and quality of life of the elderly, it was confirmed that the health and quality of life were higher in those following an active and balanced lifestyle. In addition, gender, education level and residential area were analyzed as predictive factors. Conclusion : The health and quality of life of the elderly can be improved when they have balanced lifestyle. Therefore, an empirical and policy intervention strategy should be developed and implemented to enhance the health and quality of life of the elderly.

An Analysis of Environmental Factors of Abandoned Paddy Wetlands as References and Changes in Land Cover Types in the Influence Area (묵논습지 환경요인 및 생태영향권 내 토지피복유형 변화 분석)

  • Park, MiOk;Kwon, SoonHyo;Back, SeungJun;Seo, JooYoung;Koo, BonHak
    • Journal of Wetlands Research
    • /
    • v.24 no.4
    • /
    • pp.331-344
    • /
    • 2022
  • This study analyzed the characteristics of the soil and hydrological environment of abandoned paddy wetlands examined the changes in land cover type in the ecological affect area, analyzed the environmental factors of abandoned paddy wetlands, and examined the changes in land cover type in the ecological impact area. The ecological environment characteristics of the reference abandoned paddy wetlands were investigated through literature research, environmental spatial information service, and preliminary exploration of the abandoned paddy wetlands, and the basic data for the restoration of abandoned paddy wetlands ware provided by examining the changes in land cover type in the ecological impact area for 40 years. Through this study, it will be possible to manage the rapidly increasing number of abandoned farmland to be converted into wetlands so that it can perform functions equivalent to or greater than that of natural wetlands. In particular, as we checked the clues that abandoned paddy wetlands could spread to surrounding ecological influences through land cover changes, the study sites are highly likely to be reference wetlands, and if the topography, soil, water circulation system, and carbon reduction performance are analyzed carefully, it will be possible to standardize the development process. In addition, through the change in land cover, clues were confirmed that the abandoned paddy wetlands could spread to the surrounding ecological affect areas. The land cover type in the ecological impact area, forests was mainly distributed, but generally decreased rapidly in the last 10-20 years, and forests were changing from coniferous forests to broad-leaved forests, mixed forests, or grassland. It has not yet been fully called to the wetland, and it is found that it has maintained the form of barren or grassland, and as can be seen in the case of natural wetlands after more than 30 years after abandoned, it is expected that the transition will gradually proceed to wetlands that are structurally and functionally similar to natural wetlands.