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A Study on the Seasonal Water Quality Characteristics and Suitability of Waterfront Activitiesin Waterfront Areas (친수지구의 계절별 수질특성과 친수활동의 적합성에 관한 연구)

  • Taek-Ho Kim;Yoon-Young Chang
    • Journal of Environmental Impact Assessment
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    • v.32 no.2
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    • pp.134-145
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    • 2023
  • Currently, the floodplains of major rivers are transforming into various types of waterfront spaces according to the increase in leisure activities and improved accessibility. In general, waterfront activities in river channels tend to be concentrated in summer, and the waterfront activities during this period directly affect water quality. Accordingly, it is necessary to accurately compare and evaluate the characteristics and water quality of waterfront activities during the period when waterfront activities are concentrated. In this study, the following research was conducted to compare and analyze the current status of waterfront activities of users of waterfront areas and the water quality of waterfront areas. First, three waterfront areas were selected for investigation using the information from the Ministry of Environment's water quality measurement network. Second, a survey was conducted on the satisfaction and types of waterfront activities targeting users of waterfront areas. Third, water quality grades were calculated based on monthly water quality measurement factors and compared. Fourth, statistical analysis (one-way analysis of variance) was conducted to see if there was a significant difference in water quality characteristics between periods of high waterfront activity and periods of low waterfront activity using water quality measurement data for the last 5 years. As a result of this analysis, the following conclusions were drawn in this study. First, the use of waterfront activities was investigated in the order of camping, water skiing, fishing, swimming, and rafting. Second, satisfaction factors for waterfront activities were investigated in the order of activity convenience, water quality, waterlandscape, transportation access convenience, and temperature. Third, it was found that satisfaction with water quality in waterfront areas was generally unsatisfactory regardless of the water quality grade presented by the competent authority. Fourth, as a result of comparing the water quality measurement network data of the Ministry of Environment by water quality grade, generally good grades were found, and in particular, there was a difference in grade frequency by season in the BOD category. Fifth, as a result of statistical analysis (one-way ANOVA) of water quality monitoring network data by season, there were statistically significant differences in COD, BOD, TP, and TOC except for DO. Considering the results of these studies, it is judged that it is necessary to prepare a comprehensive management system for water quality improvement in the waterfront zone and to improve water quality during periods of high waterfront activity, and to prepare a water quality forecasting system for waterfront areas in the future.

Modeling the Effects of Forest Management Scenarios on Aboveground Biomass and Wood Production: A Study in Mt. Gariwang, South Korea (산림경영활동에 따른 수종별 지상부생물량 및 목재생산량 변화 모델링: 가리왕산 모델숲을 대상으로)

  • Wonhee Cho;Wontaek Lim;Won Il Choi;Hee Moon Yang;Dongwook W. Ko
    • Journal of Korean Society of Forest Science
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    • v.112 no.2
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    • pp.173-187
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    • 2023
  • The forest protection policies implemented in South Korea have resulted in the significant accumulation of forest. Moreover, the associated public interest has also been closely evaluated. As forests mature, there arises a need for forest management (FM) practices, such as thinning and harvesting. It is therefore essential to perform a scientific analysis of the long-term effects of FM. In this study, conducted in Mt. Gariwang, the effect of FM on forest succession and wood production (WP) were evaluated based on changes in aboveground biomass (AGB) using the LANDIS-II model. The FM consists of three scenarios (Selection, Shelterwood, and Two-stories), characterized based on the harvest intensity, frequency, and period. The model was applied to changes in the forest over 200 years. All scenarios show that the total AGB decreased immediately after thinning and harvesting. However, AGB recovery time differed among scenarios, with recovery to preharvest level occurring from 15 to 50 years after harvest; further, after 200 years, harvested forests had a greater total AGB than forests without FMs In particular, the changes in AGB of each species was different depending on its shade tolerance. The AGB of currently dominant shade-intolerant and mid-tolerant species decreased dramatically after harvesting. However, shade-tolerant species, dominant in the understory, continued to grow but were not harvested due to their small size. The cumulative WP for each scenario was estimated at 545.6, 141.6, and 299.9 tons/ha in Selection, Shelterwood, and Two-stories, respectively. The composition of WP differed according to harvest intensity and period. Most WP originated from shade-intolerant and mid-tolerant species in the early period. Later, most WP was from shade-tolerant species, which became dominant. The modeling approach used in this study is capable of analyzing the long-term effects of FM on changes in forests and WP. This study can contribute to decision making to guide FM methods for a variety of purposes, including WP and controlling forest composition and structure.

Analysis on Dynamics of Korea Startup Ecosystems Based on Topic Modeling (토픽 모델링을 활용한 한국의 창업생태계 트렌드 변화 분석)

  • Heeyoung Son;Myungjong Lee;Youngjo Byun
    • Knowledge Management Research
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    • v.23 no.4
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    • pp.315-338
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    • 2022
  • In 1986, Korea established legal systems to support small and medium-sized start-ups, which becomes the main pillars of national development. The legal systems have stimulated start-up ecosystems to have more than 1 million new start-up companies founded every year during the past 30 years. To analyze the trend of Korea's start-up ecosystem, in this study, we collected 1.18 million news articles from 1991 to 2020. Then, we extracted news articles that have the keywords "start-up", "venture", and "start-up". We employed network analysis and topic modeling to analyze collected news articles. Our analysis can contribute to analyzing the government policy direction shown in the history of start-up support policy. Specifically, our analysis identifies the dynamic characteristics of government influenced by external environmental factors (e.g., society, economy, and culture). The results of our analysis suggest that the start-up ecosystems in Korea have changed and developed mainly by the government policies for corporation governance, industrial development planning, deregulation, and economic prosperity plan. Our frequency keyword analysis contributes to understanding entrepreneurial productivity attributed to activities among the networked components in industrial ecosystems. Our analyses and results provide practitioners and researchers with practical and academic implications that can help to establish dedicated support policies through forecast tasks of the economic environment surrounding the start-ups. Korean entrepreneurial productivity has been empowered by growing numbers of large companies in the mobile phone industry. The spectrum of large companies incorporates content startups, platform providers, online shopping malls, and youth-oriented start-ups. In addition, economic situational factors contribute to the growth of Korean entrepreneurial productivity the economic, which are related to the global expansions of the mobile industry, and government efforts to foster start-ups. Our research is methodologically implicative. We employ natural language processes for 30 years of media articles, which enables more rigorous analysis compared to the existing studies which only observe changes in government and policy based on a qualitative manner.

Evaluating of the Effectiveness of RTK Surveying Performance Based on Low-cost Multi-Channel GNSS Positioning Modules (다채널 저가 GNSS 측위 모듈기반 RTK 측량의 효용성 평가)

  • Kim, Chi-Hun;Oh, Seong-Jong;Lee, Yong-Chang
    • Journal of Cadastre & Land InformatiX
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    • v.52 no.2
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    • pp.53-65
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    • 2022
  • According to the advancement of the GNSS satellite positioning system, the module of hardware and operation software reflecting accuracy and economical efficiency is implemented in the user sector including the multi-channel GNSS receiver, the multi-frequency external antenna and the mobile app (App) base public positioning analysis software etc., and the multichannel GNSS RTK positioning of the active configuration method (DIY, Do it yourself) is possible according to the purpose of user. Especially, as the infrastructure of multi-GNSS satellite is expanded and the potential of expansion of utilization according to various modules is highlighted, interest in the utilization of multi-channel low-cost GNSS receiver module is gradually increasing. The purpose of this study is to review the multi-channel low-cost GNSS receivers that are appearing in the mass market in various forms and to analyze the utilization plan of the "address information facility investigation project" of the Ministry of Public Administration and Security by constructing the multi-channel low-cost GNSS positioning module based RTK survey system (hereinafter referred to as "multi-channel GNSS RTK module positioning system"). For this purpose, we constructed a low-cost "multi-channel GNSS RTK module positioning system" by combining related modules such as U-blox's F9P chipset, antenna, Ntrip transmission of GNSS observation data and RTK positioning analysis app through smartphone. Kinematic positioning was performed for circular trajectories, and static positioning was performed for address information facilities. The results of comparative analysis with the Static positioning performance of the geodetic receivers were obtained with 5 fixed points in the experimental site, and the good static surveying performance was obtained with the standard deviation of average ±1.2cm. In addition, the results of the test point for the outline of the circular structure in the orthogonal image composed of the drone image analysis and the Kinematic positioning trajectory of the low cost RTK GNSS receiver showed that the trajectory was very close to the standard deviation of average ±2.5cm. Especially, as a result of applying it to address information facilities, it was possible to verify the utility of spatial information construction at low cost compared to expensive commercial geodetic receivers, so it is expected that various utilization of "multi-channel GNSS RTK module positioning system"

A Semantic Analysis on the Research Trend of International Arts Management (언어네트워크분석을 활용한 해외 예술경영 연구동향 연구)

  • Shim, Dahee;Park, Yang Woo
    • Korean Association of Arts Management
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    • no.49
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    • pp.5-35
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    • 2019
  • The main purpose of this study was to use semantic network analysis to examine the international trend of arts management and other studies pertinent to this field. The subject was based on 357 keywords listed on the abstract of 185 research papers in the International Journal of Arts Management. To examine the most current trends of arts management based studies the time frame was restricted from 2008 to 2017. To briefly summarize the result, first, 'museum' was the most frequently appeared keyword. This was followed by 'performing arts' and 'arts' with more than 20 appearances. 'Motion picture industry' and 'theater' were the next frequently appeared keywords. 'Customer behavior' and 'market strategy', keywords related to management, were also included in the high ranked group along with art related keywords. Second, yearly research trend shows that arts management has been regularly studied for past ten years with average of 19 research papers with about 53 keywords. Keywords such as 'museum' and 'performing arts' has been regularly studied for past ten years. 'Culture', 'theater' and 'motion pictures industry' does not regularly appear in the result of yearly research trend but nevertheless they have sparsely made an appearance along the past decade. 'Art gallery' has not been cited till 2011 but from 2012 it was regularly and continuously made an appearance in the yearly research trend. Overall, the yearly trend result shows that the trend of international arts management studies within IJAM, was at first centered on fine arts but as the time passed there has been diversified keywords related to management. Third, 'performing art' and 'art' has the highest link frequency(34). Fourth, density result was 0.039 which shows that the keyword density is not very high. Fifth, 'art', 'performing art', 'museum', 'theater' and 'brand' were positioned in the middle when looking at the visualized version of centrality result. This means that these five keywords has the highest centrality among other keywords.

Characteristics of User's Behavior across Generations for space planing in General Hospital (종합병원 환경계획을 위한 세대별 종합병원 이용행태 특성분석)

  • Park, Hey Kyung;Oh, Ji Young
    • Korea Science and Art Forum
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    • v.28
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    • pp.105-116
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    • 2017
  • This study is a basic research to suggest user-centered general hospital environmental design guidelines, which aims to analyze user's behavior characteristics across generation in general hospital. For this purpose, this study constructed an analysis tool through the literature review with regard to generation and behavior characteristics in general hospital. Besides, an online survey regarding user's behavior in general hospital was conducted targeting from 20s to 60s, 300 persons for each group, total 1,500 persons for about 3 weeks since September 1, 2016. The results of this study are as follows: (1) Based on the generation, there were significant differences in relevant categories of their visiting frequency, visiting purpose, visiting hour, transportation, companion, behavior during the wait and selection of a general hospital. (2) In all generation, they responded that they have visited once or twice per year. People in 20s and 30s responded that their visit for the hospital is to receive specific treatment, while other people in 40s, 50s and 60s visit the hospital majorly for routine check-ups. Therefore, it is imperative for a health check-up center to design an environmental plan that reflects the characteristics of elders in 40s, 50s and 60s. (3) People in 40s, 50s and 60s usually visit a general hospital in the mornings of weekdays, while generations in 20s and 30s responded that they mostly visit the hospital in the mornings of weekend. (4) When they visit a general hospital, people in their 20s are usually using public transportations, while people in their 30s to 60s are using their own vehicle. (5) People in their 20s majorly visited 'lobby'. In older generations, they tend to visit 'outpatient clinic'. Therefore, it is necessary to build an outpatient clinic environment that considers the elderly. (6) Patients majorly responded that they are using their cell phone, while waiting for their clinic call. In elder generations, they responded that they are more likely watching TVs, reading books/magazines or doing nothing. Therefore, it is essential to provide cell-phone related services and environmental supports. Visually attractive media can be utilized for this purpose.

Examining the Influence of Science Museum Service Quality on Customer Satisfaction and Revisit Intention - A Case of Gwacheon National Science Museum - (과학관 서비스 품질이 고객만족도 및 재방문 의도에 미치는 영향 분석 - 국립과천과학관을 중심으로 -)

  • Choi, Jung won;Nam, Tae woo;Cho, Jae min
    • Korea Science and Art Forum
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    • v.27
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    • pp.277-288
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    • 2017
  • The number of science museums in Korea has expanded quantitatively from 72 in 2008 to 128 in 2016. This study started with the fact that the government puts a lot of budget into building a science museum, but there are more than one quarter of science museums with less than 50 spectators per day and many inefficient institutions. The number of visitors is an important factor in improving the efficiency of the science museum operation. The purpose of this study is to analyze the relation between the service quality of the science museum and the customer satisfaction and the intention to revisit and to find out what kind of effort should be concentrated in the science museum to attract more visitors. Questionnaires were written in the exhibition, education, and culture fields of the Gwacheon National Science Museum. The results were derived by frequency analysis, reliability analysis, factor analysis, and multiple regression analysis. The results and contents of the study are as follows. First, in the field of exhibition, the quality of exhibition facilities was expected to affect customer satisfaction and intention to return, but did not have a meaningful relationship. Second, the education sector has been found to affect customer satisfaction and return intention in all aspects of service quality (operation and contents, instructors, educational facilities and environment). Third, in the field of culture (event), the quality of the cultural program influences the visitor satisfaction, but it does not affect the intention to revisit. The science museum can provide satisfaction to visitors by combining activities such as science and arts. Despite the limitations, it is necessary to make efforts to improve the visitor satisfaction and revisit by proceeding with the convergence research on the entire National Science Museum in the future.

Image Evaluation for Optimization of Radiological Protection in CBCT during Image-Guided Radiation Therapy (영상유도 방사선 치료 시 CBCT에서 방사선 방호최적화를 위한 영상평가)

  • Min-Ho Choi;Kyung-Wan Kim;Dong-Yeon Lee
    • Journal of the Korean Society of Radiology
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    • v.17 no.3
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    • pp.305-314
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    • 2023
  • With the development of medical technology and radiation treatment equipment, the frequency of high-precision radiation therapy such as intensity modulation radiation therapy has increased. Image-guided radiation therapy has become essential for radiation therapy in precise and complex treatment plans. In particular, with the introduction of imaging equipment for diagnosis in a linear accelerator, CBCT scanning became possible, which made it possible to calibrate and correct the patient's posture through 3D images. Although more precise reproduction of the patient's posture has become possible, the exposure dose delivered to the patient during the image acquisition process cannot be ignored. Radiation optimization is necessary in the field of radiation therapy, and efforts to reduce exposure are necessary. However, when acquiring 3D CBCT images by changing the imaging conditions to reduce exposure, there should be no image quality or artefacts that would make it impossible to align the patient's position. In this study, Rando phantom was used to scan and evaluate images for each shooting condition. The highest SNR was obtained at 100 kV 80 mA 25 ms F1 filter 180°. As the tube voltage and tube current increased, the noise decreased, and the bowtie filter showed the optimal effect at high tube current. Based on the actual scanned images, it was confirmed that patient alignment was possible under all imaging conditions, and that image-guided radiation therapy for patient alignment was possible under the condition of 70 kV 10 mA 20 ms F0 filter 180°, which showed the lowest SNR. In this study, image evaluation was conducted according to the imaging conditions, and low tube voltage, tube current, and small rotation angle scan are expected to be effective in reducing radiation exposure. Based on this, the patient's exposure dose should be kept as low as possible during CBCT imaging.

A Study on Changes of Symptoms and Signs Diagnosised by Differentiation of the Pattern Identification in Acute Ischemic Stroke Patients with Collaborative Treatment (한·양방 병행치료를 시행한급성기 뇌경색 환자에게 변증(辨證)별 평가항목 호전도에 대한 연구)

  • Lu, Hsu-yuan;Kim, Soo-kyung;Shim, So-ra;Kim, Hye-mi;Park, Joo-young;Cho, Seung-yeon;Park, Seong-uk;Jung, Woo-sang;Moon, Sang-kwan;Park, Jung-mi;Ko, Chang-nam;Cho, Ki-ho;Kim, Young-suk;Bae, Hyung-sup
    • The Journal of the Society of Stroke on Korean Medicine
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    • v.12 no.1
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    • pp.16-23
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    • 2011
  • Object : The purpose of this study is to observe the changes of symptoms and signs diagnosised by differentiation of the pattern identification in stroke patients. Methods : Seventy subjects were recruited from patients with stroke within ten days of onset. We chose twenty-nine subjects diagnosised as same differentiation of the pattern identification, and who had at least on follow up session. We had investigated change of symptoms and signs diagnosised by differentiation of the pattern identification. Results : There were five symptoms and signs (thick fur, dry fur, difficult defecation, heat vexation and aversion to heat, normal pulse) and ten (heavy-headedness, frequency of defecation, hard defecation, feel heavy, slippery pulsem, dry mouth, bitter taste in the mouth, feel lazy, look lazy) symptoms and signs that were statistically significant improved in fire-heat patterns and dampness-phlegm pattern, respectively. Conclusions : This study provides evidence that collaborative treatment is effective in improving some symptoms and signs in acute ischemic stroke patients diagnosised by fire-heat pattern and dampness-phlegm pattern. Further studies with larger scale, longer observation period would be required.

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Effects of Muscle Activation Pattern and Stability of the Lower Extremity's Joint on Falls in the Elderly Walking -Retrospective Approach- (노인 보행 시 하지 근 활동 양상과 관절의 안정성이 낙상에 미치는 영향 -후향성 연구-)

  • Ryu, Jiseon
    • 한국체육학회지인문사회과학편
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    • v.57 no.3
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    • pp.345-356
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    • 2018
  • Objective: The purpose of this study was to investigate the local stability of the lower extremity joints and muscle activation patterns of the lower extremity during walking between falling and non-falling group in the elderly women. Method: Forty women, heel strikers, were recruited for this study. Twenty subjects (age:72.55±5.42yrs; height:154.40±4.26cm; mass:57.40±6.21kg; preference walking speed:0.52±0.17m/s; fall frequency=1.70±1.26 times) had a history falls(fall group) within two years and Twenty subjects (71.90±2..90yrs; height:155.28±4.73cm; mass:56.70±5.241kg; preference walking speed: 0.56±0.13m/s) had no history falls(non-fall group). While they were walking on a instrumented treadmill at their preference speed for a long while, kinematic and EMG signals were obtained using 3-D motion capture and wireless EMG electrodes, respectively. Local stability of the ankle and knee joint were calculated using Lyapunov Exponent (LyE) and muscles activation and their co-contraction index were also quantified. Hypotheses were tested using one-way ANOVA and Mann-Whitey. Spearman rank was also used to determine the correlation coefficients between variables. Level of significance was set at p<.05. Results: Local stability in the knee joint adduction-abduction was significantly greater in fall group than non-fall group(p<.05). Activation of anterior tibials that acts on the foot segment dorsal flexion was greater in non-fall group than fall group(p<.05). CI between gastrocnemius and anterior tibials was found to be significantly different between two groups(p<.05). In addition, there was significant correlation between CI of the leg and LyE of the ankle joint flexion-extention in the fall group(p<.05). Conclusion: In conclusion, muscles that act on the knee joint abduction-adduction as well as gastrocnemius and anterior tibials that act on the ankle joint flexion-extention need to be strengthened to prevent from potential fall during walking.