• Title/Summary/Keyword: sampling disturbance

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A Motion Detection Approach based on UAV Image Sequence

  • Cui, Hong-Xia;Wang, Ya-Qi;Zhang, FangFei;Li, TingTing
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.3
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    • pp.1224-1242
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    • 2018
  • Aiming at motion analysis and compensation, it is essential to conduct motion detection with images. However, motion detection and tracking from low-altitude images obtained from an unmanned aerial system may pose many challenges due to degraded image quality caused by platform motion, image instability and illumination fluctuation. This research tackles these challenges by proposing a modified joint transform correlation algorithm which includes two preprocessing strategies. In spatial domain, a modified fuzzy edge detection method is proposed for preprocessing the input images. In frequency domain, to eliminate the disturbance of self-correlation items, the cross-correlation items are extracted from joint power spectrum output plane. The effectiveness and accuracy of the algorithm has been tested and evaluated by both simulation and real datasets in this research. The simulation experiments show that the proposed approach can derive satisfactory peaks of cross-correlation and achieve detection accuracy of displacement vectors with no more than 0.03pixel for image pairs with displacement smaller than 20pixels, when addition of image motion blurring in the range of 0~10pixel and 0.002variance of additive Gaussian noise. Moreover,this paper proposes quantitative analysis approach using tri-image pairs from real datasets and the experimental results show that detection accuracy can be achieved with sub-pixel level even if the sampling frequency can only attain 50 frames per second.

An Analysis of Related Factors for Major Nursing Diagnoses Identified for Instituionalized Elders (일 시설노인에게 나타난 주요 간호진단의 관련요인 분석)

  • Hur, Hea-Kung;Park, So-Mi;Kim, Gi-Yon;Shin, Yun-Hee;Yim, Eun-Shil
    • Korean Journal of Adult Nursing
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    • v.15 no.1
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    • pp.126-136
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    • 2003
  • Purpose: The purpose of this study was to analyze related factors for major nursing diagnoses used in caring for institutionalized elders. Method: This study was a descriptive study. The participants were 92 residents in a long-term care facility in Wonju, selected by convenience sampling. The instrument was a checklist designed on the basis of the related factors suggested by NANDA (1997) and a literature review. Data was collected by chart review, observation, and interviews with the participants. Data was analyzed using descriptive statistics with the SPSS WIN program. Result: The most frequent nursing diagnosis was 'risk for injury', 'self-esteem disturbance', 'activity intolerance', 'impaired phyical mobility', and 'powerlessness'. The most frequent component for related factors for the five component for each nursing diagnosis was the physical component, followed by the social component. Common related factors for the nursing diagnoses were 'pain', 'change of emotional state/disorder', 'cognitive disorder', 'change of physical structure and function', and 'physical impairment', and 'immobility'. Conclusion: The results of this study can contribute to the development of appropriate nursing intervention programs for elders (eg. 'Injury Prevention Programs', 'Self-esteem Improvement Programs' etc.). Clinical guidelines that gerontological nurses can use to accurately assess health problems and select appropriate nursing interventions may be developed.

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Relationship between Abundances of Kaloula borealis and Meteorological Factors based on Habitat Features (서식지 특성에 따른 맹꽁이 개체수와 기상요인과의 관계 분석)

  • Rho, Paikho
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.19 no.3
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    • pp.103-119
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    • 2016
  • This study aims to assess habitat feature on the large-scale spawning ground of the Boreal Digging Frog Kaloula borealis in Daemyung retarding basin of Daegu, and to analyze the relationships between species abundance and meteorological factors for each habitat. Fifty-seven(57) pitfalls were installed to collect species abundance of 4 survey regions, and high-resolution satellite image, soil sampling equipment, digital topographic map, and GPS were used to develop habitat features such as terrain, soil, vegetation, human disturbance. The analysis shows that the frog is most abundant in sloped region with densely herbaceous cover in southern part of the retarding basin. In the breeding season, lowland regions, where Phragmites communis and P. japonica dominant wetlands and temporary ponds distributed, are heavily concentrated by the species for spawning and foraging. Located in between legally protected Dalsung wetands and lowland regions of the retarding basin, riverine natural levee is ecologically important area as core habitat for Kaloula borealis, and high number of individuals were detected both breeding and non-breeding seasons. Temperate- and pressure-related meteorological elements are selected as statistically significant variables in species abundance of non-breeding season in lowland and highland regions. However, in sloped regions, only a few variables are statistically significant during non-breeding season. Moreover, breeding activities in sloped regions are statistically significant with minimum temperature, grass minimum temperature, dew point temperature, and vapor pressure. Significant meteorological factors with habitat features are effectively applied to establish species conservation strategy of the retarding basin and to construct for avoiding massive road-kills on neighboring roads of the study sites, particularly post-breeding movements from spawning to burrowing areas.

The Influence of Perfectionism and Ego-resiliency on Anxiety by Leisure Activity in Nursing Students (간호대학생의 여가활동에 따른 완벽성과 자아탄력성이 불안에 미치는 영향)

  • Jeon, Hae Ok;Kim, Ji Hye
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.7
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    • pp.134-143
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    • 2016
  • This study examined the effects of perfectionism and ego-resiliency on the anxiety in two groups of nursing students: leisure activity, and no leisure activity group. A total of 134 undergraduate students were recruited at two universities in A and B cities, Korea using the convenient sampling method. They were asked to complete a self-reported questionnaire for 11 days in October, 2015. The results showed that there were significant differences in the ego-resiliency (t=-3.80, p=.001) and anxiety (t=3.71, p<.001) according to the leisure activity. In the subjects who did not have leisure activities, perfectionism (${\beta}=.71$, p<.001) and ego-resiliency (${\beta}=-.29$, p=.003) were identified as significant predictors of anxiety and this model explained 58.0% of the variance in anxiety (F=34.50, p<.001). In the analysis according to the classification of current leisure activity, Perfectionism (${\beta}=.54$, p=.003) was identified as a significant predictor of anxiety in subjects doing travel watch and pastime amusement, and this model explained 26.0% of the variance in anxiety in nursing students (F=5.66, p=.009). Therefore, providing strategies to control anxiety can not only improve ego-resiliency, but also reduce perfectionism among nursing students. In addition, it is necessary to resolve the disturbance factors of the leisure activity and create an environment that promotes leisure activities in universities.

Long-term Changes of Fish Ecological Characteristics on the Gwanpyeong Stream Development and the Necropsy-based Health Assessments (관평천 개발에 따른 장기간 어류 생태적 특성 변화 및 해부학적 건강도 평가)

  • Oh, Ja Yun;Lee, Sang-Jae;An, Kwang-Guk
    • Korean Journal of Environment and Ecology
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    • v.34 no.4
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    • pp.282-293
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    • 2020
  • This study investigated a long-term variation trend of water quality, fish compositions, and ecological health conditions in the Gwanpyeong stream located in the nearby Daejeon metropolitan city to understand the impact of urban development projects on the aquatic ecosystem. The sampling was made in four surveys (2009, 2010, 2016, 2019) before and after urbanization. The urban development was conducted in 2008, resulting in the stream's ecological disturbance, and the stream restoration was conducted in 2012. Thus, stream monitoring was conducted to analyze the ecological trends before and after the restoration. The multi-metric models for Fish Assessment Index(FAI) and necropsy-based Health Assessment Index(HAI) were applied in the fish community and organ-level, respectively, to assess the ecological health of the stream. Minimum turbidity and chlorophyll-a(Chl-a) occurred in the mid-stream(St. 2), and this was probably due to rapid current velocity in the riffle zone. We collected 18 fish species, and the dominant species was Zacco platypus (40.6%). In 2016 immediately after the stream restoration, the relative proportions of sensitive species and insectivore species were the highest along with highest values in the species diversity and species richness index, resulting in the best condition in the ecological health, based on FAI model values. However, the ecological health, based on the FAI, became worse in the latest survey conducted in 2019. The analysis of the HAI model based on the organ-level approach showed skin erosion in the fish of upper stream, kidney defects in downstream, and the liver and gill defects observed in all sites, indicating that the anatomical health was also affected.

Analysis of Vegetational Community Structure and Phytosociological Changes During Eight Years of the Namsan Nature Park in Seoul (남산자연공원(南山自然公園)의 식물군집구조(植物群集構造) 및 8년간(年間)의 식생변화분석(植生變化分析))

  • Lee, Kyong-Jae;Park, In-Hyeop;Oh, Koo-Kyoon
    • Journal of Korean Society of Forest Science
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    • v.76 no.3
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    • pp.206-217
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    • 1987
  • To investigate and analyze the vegetational structure, thirty sites were sampled with clumped sampling method and seventeen belt transects were sampled to analyze the vegetational change during 8 years(from 1978 to 1986)at the Namsan Nature Park in Seoul. Robinia pseudoacacia community of actual vegetation covered 29.39%, Quercus mongolica community 21.25% and Pinus densiflora community 17.58% of the Mt. Namsan forest. The degree of human disturbance of vegetation of 8, 7 and 6 area covered 43.2%, 7.8% and 30.8% respectively. The Quercus mongolica community at the northern slope and R. pseudoacacia community at the edge zone will keep their present structure. And P. densiflora community at the eastern and southern slope shall be succeeded to deciduous trees such as Q. mongolica. As to changes of plant community structure during 8 years, density of understory species, species diversity and Raunkiaer's frequency class A and E showed an increase and vegetation structure was developed to unification.

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The Fish Fauna and Community of Chogang Stream, Korea (초강천의 어류상과 군집)

  • Hur, Jun-Wook;Park, Jin-Woo;Kim, Jeong-Kon
    • Korean Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.271-278
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    • 2010
  • Field monitoring was conducted for fish fauna and community assessment at 7 sites from April 2008 to October 2009 in the Chogang Stream. The number of fish samples in this period were 4,669 in 36 species of 9 families. Family Cyprinidae take 66.7 (24 species), Cobitidae, Bagridae, Centropomidae and Odontobutidae occupied 5.6%(each 2 species), respectively. Twenty species (55.6%) including Acheilognathus koreensis and A. yamatsutae were found endemic out of the 36 species. The species of Pseudopungtungia nigra, Gobiobotia macrocephala and Gobiobotia brevibarba were endangered species. The most frequently found one was Zacco koreanus (34.0%, n=1,588) followed by Z. platypus (22.6%, n=1,053) and Coreoleuciscus splendidus (13.3%, n=623). The lower reach of Chogang Stream was more abundance of species, high diversity, evenness and richness, and lower dominance index than those of the upper reach. According to the dendrogram established at 0.5 level of similarity rate, sampling stations were divided into 3 groups. They were divided into upper most stream (St. 1~St. 2), upper stream (St. 3), middle and lower stream (St. 4~St. 7). Overall, it was concluded that the Chogang Stream has been relatively well protected from the anthropogenic disturbance for the legally protected species including the endemic species studied in this study.

Water Depth Change Caused by Artificial Structures in Geum River Estuary: Spatio-Temporal Evaluation Based on GIS (금강하구에서 인공 구조물에 의한 수심 변화 : GIS 기반의 시.공간 평가)

  • Lee, Hyun-Hee;Um, Jung-Sup
    • Journal of the Korean Geographical Society
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    • v.42 no.1 s.118
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    • pp.121-132
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    • 2007
  • This paper examines the spatial and temporal variability in the water depth caused by artificial structures in Geum Estuary of South Korea. Water depth data set extracted from marine maps of 1979, 1990, 1996 and 2004 were used in a GIS to derive volumetric estimates of gains and losses of sedimentary material. Artificial structures caused above 2m in water depth to be shallow between 1979 and 2002 in the estuary system, particularly through disturbance of a natural transport in suspended sediment concentrations. The mutt significant change in suspended sediment transport were observed in area affected by embankment for fresh water, inducing the water depth shallower than before in almost 80% of the area. This was probably because of an continuous abundant mud supply from coastal river oven after blocking the fresh water. The spatial analysis made it possible to identify area wide patterns of water depth change subject to many different type of artificial structures, which tanner be acquired by traditional field sampling. It is anticipated thai this research could be used as a valuable reference to confirm the outputs from past field researches for sedimental process in more visual and quantitative manner.

A Study on the Distribution Patterns of Salicaceae species at the An-sung Stream - Refered to Woldongcheon, Yokjungcheon, Joyoungcheon and Gisolcheon - (안성천 수계의 버드나무과 식물의 분포특성에 관한 연구 - 월동천, 옥정천, 조령천, 기솔천을 중심으로 -)

  • 안영희;양영철;전승훈
    • Korean Journal of Environment and Ecology
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    • v.15 no.3
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    • pp.213-223
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    • 2001
  • This study was carried out to clarify the distribution pattern of Salicaceae species which are considered as obligatory riparian vegetation, and also the correspondence between their distribution and the environment factors. Eighty-three study sites by stratified sampling were selected from the upstream to the downstream of An-sung stream. Vegetation factors such as coverage by species, disturbance, etc., and environmental factors including microtopography, soil properties, etc., measured and analyzed. Salicaceae species were identified as total 2 genera, 11 species through all study area, and the average occurring species were 2.8 species.5. koreensis among other species showed highest occurring frequency at An-sung streams, and also it was distributed widely through study area. S. gracizistyla was mainly fecund at upstream sites, where sandy soil texture and high longitudinal slope were developed. S. purpurea vats. japonica was mostly observed in the sandy soil, the same as S. gracilistytu and however, was not dominant but rather mixed with S. gracitistyta and S. koreensis. On the other hand, distribution of S. glandulosa were closely related with littoral zone of the lake and the lower sea level with sandy loam and loamy sand Boils of high organic matter content. Under CCA, canonical correspondence analysis, distribution of Saticaceae species was positively correlated with environmental gradients such as soil properties along to topography.

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The Impact of Sand Addition to An Intertidal Area for the Development of the Manila Clam, Ruditapes philippinarum Habitat on Benthic Community Structure - the case of an sandbank in Gonam-myeon, Taean-gun - (바지락 치패발생장 조성을 위한 모래살포가 저서동물 군집구조에 미치는 영향 - 태안군 고남면 모래톱 갯벌 사례 -)

  • Yoon, Sang-Pil;Song, Jae-Hee;Kim, Youn-Jung;An, Kyoung-Ho
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.17 no.4
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    • pp.270-282
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    • 2012
  • This study was conducted to investigate the impact of sand addition to an intertidal for the development of the Manila clam habitat on benthic community structure. For this, we focused on the spatio-temporal changes in the surface sediment condition and benthic community structure before and after the event. Study site was an sandbank in Gonam-myeon, Taean-gun where sand added to on July 2010. We set three stations at each of sand adding area (experimental plot) and non sand-adding area (control plot) and did sampling works ten times from June 2010 to October 2011. Directly after the event, surface sediments changed to very coarse sand, but the state was not maintained over four months because of seasonal sedimentation and finally got back to very fine sand in eight months. The number of species and density were temporarily reduced right after the event and crustacean species such as Apocorophium acutum, Photis sp. were most negatively affected by the event. However, the number of species recovered from the reduction in three months and density did in four months due to the recolonization by the existing species and species in the vicinity of the plot. During the study period, dominant species continuously changed from the species such as A. acutum, Photis sp. at the time before the event, through the species such as Heteromastus filiformis, Macrophthalmus japonicus at the time right after the event, to the species such as Musculista senhousia, Ruditapes philippinarum, Mediomastus californiensis in the latter part of the study period. Although surface sediment properties and ecological indices recovered within a certain period after the event, the recovery of community structure has never been observed up to the end of the study.