• Korean Journal of Remote Sensing
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• v.37 no.6_3
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• pp.2027-2034
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• 2021

Using multi-temporal KOMPSAT-3/3A high-resolution satellite images, the Normalized Difference Vegetation Index (NDVI) for the area around the Fukushima daiichi nuclear power plant was determined, and the pattern of vegetation changes was analyzed. To calculate the NDVI, surface reflectance from the KOMPSAT-3/3A satellite image was used. Satellite images from four years were used, and the zones where the images overlap was designated as the area of interest (AOI) for the study, and by setting a profile passing through highly vegetated area as a data analysis method, the changes by year were examined. In addition, random points were extracted within the AOI and displayed as a box plot to quantitatively indicate change of NDVI distribution pattern. The main results of this study showed that the NDVI in 2014 was low within AOI in the vicinity of the nuclear power plant, but vegetated area continued to expand until 2021. These results were also confirmed in the change monitoring results shown in a profile or box plot. In disaster areas where access is restricted, such as the Fukushima nuclear power plant area, where it is difficult to collect field data, obtaining land cover classification products with high accuracy using satellite images is challenging, so it is appropriate to analyze them using primary outputs such as vegetation indices obtained from high-resolution satellite imagery. It is necessary to establish an international cooperation system for jointly utilizing satellite images. Meanwhile, to periodically monitor environmental changes in neighboring countries that may affect the Korean peninsula, it is necessary to establish utilization models and systems using high-resolution satellite images.

• KIPS Transactions on Software and Data Engineering
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• v.10 no.7
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• pp.279-286
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• 2021

Recently, We are carrying out a policy of physical distancing of at least 1m from each other to prevent the spreading of COVID-19 disease in public places. In this paper, we propose a method for measuring distances between people in real time and an automation system that recognizes objects that are within 1 meter of each other from stereo images acquired by drones or CCTVs according to the estimated distance. A problem with existing methods used to estimate distances between multiple objects is that they do not obtain three-dimensional information of objects using only one CCTV. his is because three-dimensional information is necessary to measure distances between people when they are right next to each other or overlap in two dimensional image. Furthermore, they use only the Bounding Box information to obtain the exact coordinates of human existence. Therefore, in this paper, to obtain the exact two-dimensional coordinate value in which a person exists, we extract a person's key point to detect the location, convert it to a three-dimensional coordinate value using Stereo Vision and Camera Calibration, and estimate the Euclidean distance between people. As a result of performing an experiment for estimating the accuracy of 3D coordinates and the distance between objects (persons), the average error within 0.098m was shown in the estimation of the distance between multiple people within 1m.

• Journal of the Korean Geosynthetics Society
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• v.17 no.4
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• pp.53-64
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• 2018

In this study, the evaluation to probability of failure for risk assessment of port structures on DCM reinforced soils, where stability and risk assessment are increasing in importance, was performed. As a random variables affecting the risk of DCM improved ground, the design strength, superposition (overlap) of construction, strength of the natural ground, internal friction angle and unit weight of the modified ground were selected and applied to the risk assessment. In addition, the failure probability for the entire system under ordinary conditions and under earthquake conditions were analyzed. As a result, it was found that the highest coefficient of variation in the random variable for the risk assessment of the DCM improved ground is the design strength, but this does not have a great influence on the safety factor, ie, the risk of the system. The main risk factor for the failure probability of the system for the DCM reinforced soils was evaluated as horizontal sliding in case of external stability and compression failure in case of internal stability both at ordinary condition and earthquake condition. In addition, the failure probability for ordinary horizontal sliding is higher than that for earthquake failure, and the failure probability for ordinary compression failure is lower than that for earthquake failure. The ordinary failure probability of the entire system is similar to the failure probability on earthquake condition, but in this case, the risk of earthquake is somewhat higher.

• Journal of Digital Convergence
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• v.16 no.11
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• pp.419-432
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• 2018

The purpose of this study is to develop a hospice intervention program and present basic study data using a method of Meta analysis. Fifteen theses from 2002 to 2017 were collected from the on-line database at Korean Education and Research Information Service and other journals related hospice. Main keywords were 'hospice' and intervention'. The selected 15 theses were analyzed with publication bias, outcome of effect size, non-overlap percentage(U3), 95% confidence intervals and homogeneity. The result of the study is summarized as follows; Publication bias was stable and the effect size of hospice program was significant at. 99. The effective and significant regulation effects were publication years with 2003 to 2007(ES=1.24), publication types with journals(ES=1.33), majors with nursing sciences(ES=1.02), ages with 29 to 30(ES=1.09), later session(ES=1.06) and aroma(ES=1.12). Accordingly, this thesis has its meaning in that it used a Meta-analysis to analyze domestic theses of hospice intervention programs for the first time in Korea. This thesis will prodide specific guidance to researchers trying to develop and utilize hospice intervention programs resulting in helpful usages in professional hospice institutions with implementations of programs.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.3
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• pp.177-188
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• 2019

Recently, citizens are feeling anxious as 'Motiveless Crime' increases. The quality of citizens life is degraded and the degree of crime fear is increasing. In this study, based on various variables related to crime other than actual crime occurrence status, crime occurrence points (point line polygon) felt by citizens are created by using mental map methodology. And the purpose of this study is to derive the area of concern for crime through spatial overlap analysis using kernel density estimation analysis. It also uses spatial overlay analysis using kernel density estimation to derive areas of concern for crime occurrence. As a result, the local residents' request point and the areas of concern for crime were overlapped. In addition, the mental map indicating the fear of crime was constructed by mapping mainly the areas between the facilities, the non-construction area such as the narrow area, the security CCTV, the streetlight. This study is meaningful in that it tried to derive a crime occurrence concern area by using mental map method unlike the previous study related to crime. The results of this study, such as mental map, could be used in various fields such as construction of fragile crime map, guideline of crime prevention through environment design.

• Journal of Neurogastroenterology and Motility
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• v.25 no.3
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• pp.343-362
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• 2019

Background/Aims There has been major progress in our understanding of the irritable bowel syndrome (IBS), and novel treatment classes have emerged. The Rome IV guidelines were published in 2016 and together with the growing body of Asian data on IBS, we felt it is timely to update the Asian IBS Consensus. Methods Key opinion leaders from Asian countries were organized into 4 teams to review 4 themes: symptoms and epidemiology, pathophysiology, diagnosis and investigations, and lifestyle modifications and treatments. The consensus development process was carried out by using a modified Delphi method. Results Thirty-seven statements were developed. Asian data substantiate the current global viewpoint that IBS is a disorder of gut-brain interaction. Socio-cultural and environmental factors in Asia appear to influence the greater overlap between IBS and upper gastrointestinal symptoms. New classes of treatments comprising low fermentable oligo-, di-, monosacharides, and polyols diet, probiotics, non-absorbable antibiotics, and secretagogues have good evidence base for their efficacy. Conclusions Our consensus is that all patients with functional gastrointestinal disorders should be evaluated comprehensively with a view to holistic management. Physicians should be encouraged to take a positive attitude to the treatment outcomes for IBS patients.

• Smart Structures and Systems
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• v.29 no.1
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• pp.1-16
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• 2022

Despite recent breakthroughs in deep learning and computer vision fields, the pixel-wise identification of tiny objects in high-resolution images with complex disturbances remains challenging. This study proposes a modified U-net for tiny crack segmentation in real-world steel-box-girder bridges. The modified U-net adopts the common U-net framework and a novel Self-Attention-Self-Adaption (SASA) neuron as the fundamental computing element. The Self-Attention module applies softmax and gate operations to obtain the attention vector. It enables the neuron to focus on the most significant receptive fields when processing large-scale feature maps. The Self-Adaption module consists of a multiplayer perceptron subnet and achieves deeper feature extraction inside a single neuron. For data augmentation, a grid-based crack random elastic deformation (CRED) algorithm is designed to enrich the diversities and irregular shapes of distributed cracks. Grid-based uniform control nodes are first set on both input images and binary labels, random offsets are then employed on these control nodes, and bilinear interpolation is performed for the rest pixels. The proposed SASA neuron and CRED algorithm are simultaneously deployed to train the modified U-net. 200 raw images with a high resolution of 4928 × 3264 are collected, 160 for training and the rest 40 for the test. 512 × 512 patches are generated from the original images by a sliding window with an overlap of 256 as inputs. Results show that the average IoU between the recognized and ground-truth cracks reaches 0.409, which is 29.8% higher than the regular U-net. A five-fold cross-validation study is performed to verify that the proposed method is robust to different training and test images. Ablation experiments further demonstrate the effectiveness of the proposed SASA neuron and CRED algorithm. Promotions of the average IoU individually utilizing the SASA and CRED module add up to the final promotion of the full model, indicating that the SASA and CRED modules contribute to the different stages of model and data in the training process.

• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.3
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• pp.59-73
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• 2022

Currently, the conflict between use and conservation of the ocean is intensifying in the ocean, so it is essential to introduce an effective method to define and manage it in advance for each core value of ocean. Accordingly, although the ocean is divided into nine marine use zone and managed through marine spatial planning, the analysis of the sea areas where mutually exclusive activities overlap in the ocean is insufficient. In this study, an automated model was developed to derive a sea areas where the core values of the ocean conflict. In order to analyze marine activities, available data on marine activity were collected, and data necessity for the analysis of mutually exclusive marine activities were derived. After classifying the derived data into legal and characteristic data, a conflict matrix was prepared through pairwise comparison between data to designate priorities when overlapping occurs. Based on the designated priorities, an automation model was developed, and sea areas where marine activities conflicted were derived, visualized, and area calculated. Using this, it is judged that the efficiency of decision-making can be improved by clearly deriving the sea areas where major issues occur in establishing the marine spatial planning.

• Journal of the Korean Geographical Society
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• v.30 no.3
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• pp.296-310
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• 1995

Classification of spatial units into meaningful sets is an important procedure in spatial analysis. It is crucial in characterizing and identifying spatial structures. But traditional classification methods such as cluster analysis require an exact database and impose a clear-cut boundary between classes. Scrutiny of realistic classification problems, however, reveals that available infermation may be vague and that the boundary may be ambiguous. The weakness of conventional methods is that they fail to capture the fuzzy data and the transition between classes. Fuzzy subsets theory is useful for solving these problems. This paper aims to come to the understanding of theoretical foundations of fuzzy spatial analysis, and to find the characteristics of fuzzy classification methods. It attempts to do so through the literature review and the case study of urban classification of the Cities and Eups of Kyung-Nam Province. The main findings are summarized as follows: 1. Following Dubois and Prade, fuzzy information has an imprecise and/or uncertain evaluation. In geography, fuzzy informations about spatial organization, geographical space perception and human behavior are frequent. But the researcher limits his work to numerical data processing and he does not consider spatial fringe. Fuzzy spatial analysis makes it possible to include the interface of groups in classification. 2. Fuzzy numerical taxonomic method is settled by Deloche, Tranquis, Ponsard and Leung. Depending on the data and the method employed, groups derived may be mutually exclusive or they may overlap to a certain degree. Classification pattern can be derived for each degree of similarity/distance $\alpha$. By takina the values of $\alpha$ in ascending or descending order, the hierarchical classification is obtained. 3. Kyung-Nam Cities and Eups were classified by fuzzy discrete classification, fuzzy conjoint classification and cluster analysis according to the ratio of number of persons employed in industries. As a result, they were divided into several groups which had homogeneous characteristies. Fuzzy discrete classification and cluste-analysis give clear-cut boundary, but fuzzy conjoint classification delimit the edges and cores of urban classification. 4. The results of different methods are varied. But each method contributes to the revealing the transparence of spatial structure. Through the result of three kinds of classification, Chung-mu city which has special characteristics and the group of Industrial cities composed by Changwon, Ulsan, Masan, Chinhai, Kimhai, Yangsan, Ungsang, Changsungpo and Shinhyun are evident in common. Even though the appraisal of the fuzzy classification methods, this framework appears to be more realistic and flexible in preserving information pertinent to urban classification.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.2
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• pp.17-20
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• 2010

Purpose: The hepatobiliary scan is the examination which is the possibility of knowing the function of liver, gall bladder and closing of the biliary tract. Also, after subtotal gastrectomy, the increased gastric-bile reflux is known as the primary reason of reflux gastritis. In this study, according to changing the acquisition method, we tried to prove the reflux time and reflux index in patients who underwent subtotal gastrectomy. Materials and Methods: From Oct 2008 to Jan 2009, 72 patients with subtotal gastrectomy who took the hepatobiliary scan (man: 52, woman: 20, age range: 31-77, mean age: $60.5{\pm}7$) in our department. We used the radiopharmaceutical $^{99m}Tc$-mebrofenin 185 MBq/0.5 cc. After 5 minutes, we acquired 300,000 counts anterior image on supine, and then we acquired right lateral and $45^{\circ}$ LAO position by using the time setting method. We acquired 30 min, 60 min, 90 min, 120 min and fatty meal by the same method. We painted the ROI of liver, GB and CBD on 30 min anterior image and LAO image in patients had occurred the bile juice reflux. And then we painted the ROI of stomach on others image. We calculated the reflux index from those values. Results: According to this study, we found out 40 patients (55.6%) who had occurred the gastric-bile juice reflux (1 person from 30 min, 7 persons from 60 min, 4 persons from 90 min, 28 persons from after fatty meal). Hourly, the bile reflux highest level is 6 persons from 60 min, 2 persons from 90 min, 32 persons from fatty meal among those people. The reflux index of anterior is 0.85-23.36% (mean 6.53%). The reflux index of LAO is 1-29.13% (mean 8.89%). By visual assessment, we can distinguish that there were 26 of the 40 patients (65%) had occurred the reflux on LAO image more than anterior image. Conclusion: We find out that the patients with subtotal gastrectomy had occurred gastric-bile juice reflux more than 50% from hepatobiliary scan. And after eating fatty meal, we can know that it's the most possible to occur the gastric-bile juice reflux. When it happened, we have to change the acquisition method to reduce the overlap between colon and stomach. This study will be more valuable in diagnosis.