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Performance Comparison of Matching Cost Functions for High-Quality Sea-Ice Surface Model Generation (고품질 해빙표면모델 생성을 위한 정합비용함수의 성능 비교 분석)

  • Kim, Jae-In;Kim, Hyun-Cheol
    • Korean Journal of Remote Sensing
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    • v.34 no.6_2
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    • pp.1251-1260
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    • 2018
  • High-quality sea-ice surface models generated from aerial images can be used effectively as field data for developing satellite-based remote sensing methods but also as analysis data for understanding geometric variations of Arctic sea-ice. However, the lack of texture information on sea-ice surfaces can reduce the accuracy of image matching. In this paper, we analyze the performance of matching cost functions for homogeneous sea-ice surfaces as a part of high-quality sea-ice surface model generation. The matching cost functions include sum of squared differences (SSD), normalized cross-correlation (NCC), and zero-mean normalized cross-correlation (ZNCC) in image domain and phase correlation (PC), orientation correlation (OC), and gradient correlation (GC) in frequency domain. In order to analyze the matching performance for texture changes clearly and objectively, a new evaluation methodology based on the principle of object-space matching technique was introduced. Experimental results showed that it is possible to secure reliability and accuracy of image matching only when optimal search windows are variably applied to each matching point in textureless regions such as sea-ice surfaces. Among the matching cost functions, NCC and ZNCC showed the best performance for texture changes.

Development of Korean SPAR(Soil-Plant-Atmosphere-Research) System for Impact Assessment of Climate Changes and Environmental Stress (기후변화 및 환경스트레스 영향평가를 위한 한국형 SPAR(Soil-Plant-Atmosphere-Research) 시스템의 개발)

  • Sang, Wan-Gyu;Kim, Jun-Hwan;Shin, Pyong;Baek, Jae-Kyeong;Lee, Yun-Ho;Cho, Jung-Il;Seo, Myung-Chul
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.21 no.3
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    • pp.187-195
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    • 2019
  • The needs for precise diagnostics and farm management-decision aids have increased to reduce the risk of climate change and environmental stress. Crop simulation models have been widely used to search optimal solutions for effective cultural practices. However, limited knowledge on physiological responses to environmental variation would make it challenging to apply crop simulation models to a wide range of studies. Advanced research facilities would help investigation of plant response to the environment. In the present study, the sunlit controlled environment chambers, known as Korean SPAR (Soil-Plant-Atmosphere-Research) system, was developed by renovating existing SPAR system. The Korean SPAR system controls and monitors major environmental variables including atmospheric carbon dioxide concentration, temperature and soil moisture. Furthermore, plants are allowed to grow under natural sunlight. Key physiological and physical data such as canopy photosynthesis and respiration, canopy water and nutrient use over the whole growth period are also collected automatically. As a case study, it was shown that the Korean SPAR system would be useful for collection of data needed for understanding the growth and developmental processes of a crop, e.g., soybean. In addition, we have demonstrated that the canopy photosynthetic data of the Korean SPAR indicate the precise representation of physiological responses to environment variation. As a result, physical and physiological data obtained from the Korean SPAR are expected to be useful for development of an advanced crop simulation model minimizing errors and confounding factors that usually occur in field experiments.

Leision Detection in Chest X-ray Images based on Coreset of Patch Feature (패치 특징 코어세트 기반의 흉부 X-Ray 영상에서의 병변 유무 감지)

  • Kim, Hyun-bin;Chun, Jun-Chul
    • Journal of Internet Computing and Services
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    • v.23 no.3
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    • pp.35-45
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    • 2022
  • Even in recent years, treatment of first-aid patients is still often delayed due to a shortage of medical resources in marginalized areas. Research on automating the analysis of medical data to solve the problems of inaccessibility for medical services and shortage of medical personnel is ongoing. Computer vision-based medical inspection automation requires a lot of cost in data collection and labeling for training purposes. These problems stand out in the works of classifying lesion that are rare, or pathological features and pathogenesis that are difficult to clearly define visually. Anomaly detection is attracting as a method that can significantly reduce the cost of data collection by adopting an unsupervised learning strategy. In this paper, we propose methods for detecting abnormal images on chest X-RAY images as follows based on existing anomaly detection techniques. (1) Normalize the brightness range of medical images resampled as optimal resolution. (2) Some feature vectors with high representative power are selected in set of patch features extracted as intermediate-level from lesion-free images. (3) Measure the difference from the feature vectors of lesion-free data selected based on the nearest neighbor search algorithm. The proposed system can simultaneously perform anomaly classification and localization for each image. In this paper, the anomaly detection performance of the proposed system for chest X-RAY images of PA projection is measured and presented by detailed conditions. We demonstrate effect of anomaly detection for medical images by showing 0.705 classification AUROC for random subset extracted from the PadChest dataset. The proposed system can be usefully used to improve the clinical diagnosis workflow of medical institutions, and can effectively support early diagnosis in medically poor area.

Predicting Functional Outcomes of Patients With Stroke Using Machine Learning: A Systematic Review (머신러닝을 활용한 뇌졸중 환자의 기능적 결과 예측: 체계적 고찰)

  • Bae, Suyeong;Lee, Mi Jung;Nam, Sanghun;Hong, Ickpyo
    • Therapeutic Science for Rehabilitation
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    • v.11 no.4
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    • pp.23-39
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    • 2022
  • Objective : To summarize clinical and demographic variables and machine learning uses for predicting functional outcomes of patients with stroke. Methods : We searched PubMed, CINAHL and Web of Science to identify published articles from 2010 to 2021. The search terms were "machine learning OR data mining AND stroke AND function OR prediction OR/AND rehabilitation". Articles exclusively using brain imaging techniques, deep learning method and articles without available full text were excluded in this study. Results : Nine articles were selected for this study. Support vector machines (19.05%) and random forests (19.05%) were two most frequently used machine learning models. Five articles (55.56%) demonstrated that the impact of patient initial and/or discharge assessment scores such as modified ranking scale (mRS) or functional independence measure (FIM) on stroke patients' functional outcomes was higher than their clinical characteristics. Conclusions : This study showed that patient initial and/or discharge assessment scores such as mRS or FIM could influence their functional outcomes more than their clinical characteristics. Evaluating and reviewing initial and or discharge functional outcomes of patients with stroke might be required to develop the optimal therapeutic interventions to enhance functional outcomes of patients with stroke.

Use of Multimedia Technologies in Extra-Curricular Works in Order to Improve the Quality of Training of Future Specialists

  • Tverezovska, Nina;Kovbasa, Tetiana;Pryhalinska, Tetiana;Mykhniuk, Serhii;Lopushan, Tetiana;Radionova, Olena;Kuchai, Tetiana
    • International Journal of Computer Science & Network Security
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    • v.22 no.9
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    • pp.35-42
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    • 2022
  • The article deals with the role of extra-curricular work by means of multimedia technologies in order to improve the quality of training of future specialists. An important condition for achieving high results in training specialists is the optimal combination of classroom and independent extra-curricular work of students by means of multimedia technologies. Very significant is the development of student independence, the formation of skills of independent search activity, the ability to take responsibility, independently solve a problem, find constructive solutions, a way out of a crisis situation, and so on. Extra-curricular work forms students' ability to master the techniques of analysis, synthesis, generalization, comparison; develops flexibility of thinking; opens up opportunities for the development and stabilization of positive learning motives to activate the process of mastering knowledge by means of multimedia technologies as a means of forming the personality of a highly qualified specialist. The concept of multimedia as one of the priority areas of Information Technology, which plays a particularly important role in the process of informatization of education, is revealed, and its advantages in education are shown. The advent of multimedia systems optimizes transformations in education, in many areas of professional activity, science, art, etc. The necessity of distance learning to improve the quality of training of future specialists using multimedia technologies in extra-curricular work is justified. The effectiveness of pedagogical support in the process of distance learning is achieved by the following conditions, which is revealed in the article. Various forms and types of extra-curricular work of students that are used in the modern practice of the educational environment of a higher education institution are described. Scientific and informational activity is considered a key area of information activity. The analysis of scientific and information activities in the field of education allows us to identify its main functions, which emphasize the growing role of scientific information in the education system, in particular, extra-curricular work using multimedia technologies. Operational, complete, accurate, targeted information that meets objective and subjective needs becomes an important link between the field of management, science and practice.

The Fault Diagnosis Model of Ship Fuel System Equipment Reflecting Time Dependency in Conv1D Algorithm Based on the Convolution Network (합성곱 네트워크 기반의 Conv1D 알고리즘에서 시간 종속성을 반영한 선박 연료계통 장비의 고장 진단 모델)

  • Kim, Hyung-Jin;Kim, Kwang-Sik;Hwang, Se-Yun;Lee, Jang Hyun
    • Journal of Navigation and Port Research
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    • v.46 no.4
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    • pp.367-374
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    • 2022
  • The purpose of this study was to propose a deep learning algorithm that applies to the fault diagnosis of fuel pumps and purifiers of autonomous ships. A deep learning algorithm reflecting the time dependence of the measured signal was configured, and the failure pattern was trained using the vibration signal, measured in the equipment's regular operation and failure state. Considering the sequential time-dependence of deterioration implied in the vibration signal, this study adopts Conv1D with sliding window computation for fault detection. The time dependence was also reflected, by transferring the measured signal from two-dimensional to three-dimensional. Additionally, the optimal values of the hyper-parameters of the Conv1D model were determined, using the grid search technique. Finally, the results show that the proposed data preprocessing method as well as the Conv1D model, can reflect the sequential dependency between the fault and its effect on the measured signal, and appropriately perform anomaly as well as failure detection, of the equipment chosen for application.

Design of an Intellectual Smart Mirror Appication helping Face Makeup (얼굴 메이크업을 도와주는 지능형 스마트 거울 앱의설계)

  • Oh, Sun Jin;Lee, Yoon Suk
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.5
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    • pp.497-502
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    • 2022
  • Information delivery among young generation has a distinct tendency to prefer visual to text as means of information distribution and sharing recently, and it is natural to distribute information through Youtube or one-man broadcasting on Internet. That is, young generation usually get their information through this kind of distribution procedure. Many young generation are also drastic and more aggressive for decorating themselves very uniquely. It tends to create personal characteristics freely through drastic expression and attempt of face makeup, hair styling and fashion coordination without distinction of sex. Especially, face makeup becomes an object of major concern among males nowadays, and female of course, then it is the major means to express their personality. In this study, to meet the demands of the times, we design and implement the intellectual smart mirror application that efficiently retrieves and recommends the related videos among Youtube or one-man broadcastings produced by famous professional makeup artists to implement the face makeup congruous with our face shape, hair color & style, skin tone, fashion color & style in order to create the face makeup that represent our characteristics. We also introduce the AI technique to provide optimal solution based on the learning of user's search patterns and facial features, and finally provide the detailed makeup face images to give the chance to get the makeup skill stage by stage.

Path Algorithm for Maximum Tax-Relief in Maximum Profit Tax Problem of Multinational Corporation (다국적기업 최대이익 세금트리 문제의 최대 세금경감 경로 알고리즘)

  • Sang-Un Lee
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.23 no.4
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    • pp.157-164
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    • 2023
  • This paper suggests O(n2) polynomial time heuristic algorithm for corporate tax structure optimization problem that has been classified as NP-complete problem. The proposed algorithm constructs tax tree levels that the target holding company is located at root node of Level 1, and the tax code categories(Te) 1,4,3,2 are located in each level 2,3,4,5 sequentially. To find the maximum tax-relief path from source(S) to target(T), firstly we connect the minimum witholding tax rate minrw(u, v) arc of node u point of view for transfer the profit from u to v node. As a result we construct the spanning tree from all of the source nodes to a target node, and find the initial feasible solution. Nextly, we find the alternate path with minimum foreign tax rate minrfi(u, v) of v point of view. Finally we choose the minimum tax-relief path from of this two paths. The proposed heuristic algorithm performs better optimal results than linear programming and Tabu search method that is a kind of metaheuristic method.

A Study on Optimized Artificial Neural Network Model for the Prediction of Bearing Capacity of Driven Piles (항타말뚝의 지지력 예측을 위한 최적의 인공신경망모델에 관한 연구)

  • Park Hyun-Il;Seok Jeong-Woo;Hwang Dae-Jin;Cho Chun-Whan
    • Journal of the Korean Geotechnical Society
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    • v.22 no.6
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    • pp.15-26
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    • 2006
  • Although numerous investigations have been performed over the years to predict the behavior and bearing capacity of piles, the mechanisms are not yet entirely understood. The prediction of bearing capacity is a difficult task, because large numbers of factors affect the capacity and also have complex relationship one another. Therefore, it is extremely difficult to search the essential factors among many factors, which are related with ground condition, pile type, driving condition and others, and then appropriately consider complicated relationship among the searched factors. The present paper describes the application of Artificial Neural Network (ANN) in predicting the capacity including its components at the tip and along the shaft from dynamic load test of the driven piles. Firstly, the effect of each factor on the value of bearing capacity is investigated on the basis of sensitivity analysis using ANN modeling. Secondly, the authors use the design methodology composed of ANN and genetic algorithm (GA) to find optimal neural network model to predict the bearing capacity. The authors allow this methodology to find the appropriate combination of input parameters, the number of hidden units and the transfer structure among the input, the hidden and the out layers. The results of this study indicate that the neural network model serves as a reliable and simple predictive tool for the bearing capacity of driven piles.

Effectiveness of Acupuncture in the Treatment of Post-Disaster Musculoskeletal Pain: A Systematic Review (재난 후 근골격계 통증에 침치료의 유효성: 체계적 문헌고찰)

  • Ka-Hyun Kim;Sung-Won Choi;Hae-Won Hong;Ju-Young Yoon;Yong-Jun Kim;Jung-Hyun Kim
    • Journal of Korean Medicine Rehabilitation
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    • v.33 no.3
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    • pp.135-148
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    • 2023
  • Objectives To investigate the effectiveness of acupuncture in the treatment of post-disaster musculoskeletal pain by reviewing relevant clinical studies. Methods A systematic search was conducted across 10 electronic databases to identify relevant clinical studies on acupuncture treatment for post-disaster musculoskeletal pain until May 2023. The methodological quality was evaluated using the Cochrane Risk of Bias 2 and Risk of Bias Assessment tool for non-randomized studies tools. Results Six articles were analyzed, including two randomized controlled trials (RCTs), two before-after studies, one qualitative research, and one case series. Overall, acupuncture therapy showed some improvement in pain scale among musculoskeletal pain survivors. However, no significant improvement was observed in the Short-Form McGill Pain Questionnaire (SF-MPQ-2). Subgroup analysis of participants who completed at least four acupuncture sessions revealed a significant effect on the SFMPQ-2. Additionally, a significant improvement in 36-Item Short Form Survey (SF36P) was observed after 6 months of treatment, but the 2-month treatment period did not show statistically significant effects on SF-36P improvement. The evaluation of the methodological quality of the RCTs identified some concerns of bias. Conclusions The results suggest that acupuncture is effective in alleviating post-disaster musculoskeletal pain. However, considering the limited number of selected studies and the inclusion of subjective evaluation measures, caution should be exercised in interpreting the results. Further large-scale follow-up studies are needed to determine the optimal frequency and duration of acupuncture treatment. Well-designed controlled trials should be conducted to provide more robust evidence regarding the effectiveness of acupuncture for post-disaster musculoskeletal pain.