• Journal of Internet of Things and Convergence
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• v.9 no.6
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• pp.23-28
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• 2023

Windows operating system generates various logs with timestamps. Timestamp tampering is an act of anti-forensics in which a suspect manipulates the timestamps of data related to a crime to conceal traces, making it difficult for analysts to reconstruct the situation of the incident. This can delay investigations or lead to the failure of obtaining crucial digital evidence. Therefore, various techniques have been developed to detect timestamp tampering. However, there is a limitation in detection if a suspect is aware of timestamp patterns and manipulates timestamps skillfully or alters system artifacts used in timestamp tampering detection. In this paper, a method is designed to detect changes in timestamps, even if a suspect alters the timestamp of a file on a storage device, it is challenging to do so with precision beyond millisecond order. In the proposed detection method, the first step involves verifying the timestamp of a file suspected of tampering to determine its write time. Subsequently, the confirmed time is compared with the file size recorded within that time, taking into consideration the performance of the storage device. Finally, the total capacity of files written at a specific time is calculated, and this is compared with the maximum input and output performance of the storage device to detect any potential file tampering.

• Journal of Korea Water Resources Association
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• v.56 no.spc1
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• pp.1027-1036
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• 2023

Coastal topographic information is crucial in coastal management, but point measurment based approeaches, which are labor intensive, are generally applied to land and underwater, separately. This study introduces an efficient method enabling land and undetwater surveys using an unmanned aerial vehicle (UAV). This method involves applying two different algorithms to measure the topography on land and water depth, respectively, using UAV imagery and merge them to reconstruct whole coastal digital elevation model. Acquisition of the landside terrain is achieved using the Structure-from-Motion Multi-View Stereo technique with spatial scan imagery. Independently, underwater bathymetry is retrieved by employing a depth inversion technique with a drone-acquired wave field video. After merging the two digital elevation models into a local coordinate, interpolation is performed for areas where terrain measurement is not feasible, ultimately obtaining a continuous nearshore terrain. We applied the proposed survey technique to Jangsa Beach, South Korea, and verified that detailed terrain characteristics, such as berm, can be measured. The proposed UAV-based survey method has significant efficiency in terms of time, cost, and safety compared to existing methods.

• The Transactions of the Korea Information Processing Society
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• v.13 no.2
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• pp.34-40
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• 2024

Secret sharing is a cryptographic technique that involves dividing a secret or a piece of sensitive information into multiple shares or parts, which can significantly increase the confidentiality of a secret. There has been a lot of research on secret sharing for different contexts or situations. Tassa's conjunctive secret sharing method employs polynomial derivatives to facilitate hierarchical secret sharing. However, the use of derivatives introduces several limitations in hierarchical secret sharing. Firstly, only a single group of participants can be created at each level due to the shares being generated from a sole derivative. Secondly, the method can only reconstruct a secret through conjunction, thereby restricting the specification of arbitrary secret reconstruction conditions. Thirdly, Birkhoff interpolation is required, adding complexity compared to the more accessible Lagrange interpolation used in polynomial-based secret sharing. This paper introduces the multi-compartment secret sharing method as a generalization of the conjunctive hierarchical secret sharing. Our proposed method first encrypts a secret using external groups' shares and then generates internal shares for each group by embedding the encrypted secret value in a polynomial. While the polynomial can be reconstructed with the internal shares, the polynomial just provides the encrypted secret, requiring external shares for decryption. This approach enables the creation of multiple participant groups at a single level. It supports the implementation of arbitrary secret reconstruction conditions, as well as conjunction. Furthermore, the use of polynomials allows the application of Lagrange interpolation.

• The Transactions of the Korea Information Processing Society
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• v.13 no.7
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• pp.326-334
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• 2024

Extra-oral imaging techniques such as Panoramic X-rays (PXs) and Cone Beam Computed Tomography (CBCT) are the most preferred imaging modalities in dental clinics owing to its patient convenience during imaging as well as their ability to visualize entire teeth information. PXs are preferred for routine clinical treatments and CBCTs for complex surgeries and implant treatments. However, PXs are limited by the lack of third dimensional spatial information whereas CBCTs inflict high radiation exposure to patient. When a PX is already available, it is beneficial to reconstruct the 3D oral structure from the PX to avoid further expenses and radiation dose. In this paper, we propose 3DentAI - an U-Net based deep learning framework for 3D reconstruction of oral structure from a PX image. Our framework consists of three module - a reconstruction module based on attention U-Net for estimating depth from a PX image, a realignment module for aligning the predicted flattened volume to the shape of jaw using a predefined focal trough and ray data, and lastly a refinement module based on 3D U-Net for interpolating the missing information to obtain a smooth representation of oral cavity. Synthetic PXs obtained from CBCT by ray tracing and rendering were used to train the networks without the need of paired PX and CBCT datasets. Our method, trained and tested on a diverse datasets of 600 patients, achieved superior performance to GAN-based models even with low computational complexity.

• Journal of Christian Education in Korea
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• v.76
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• pp.73-93
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• 2023

Purpose of study: The purpose of this study is to propose an autobiographical writing as an alternative Christian education for the elderly. Research Contents and Methods : First, after analyzing the previous studies on Christian education for the elderly, it was found that most of the studies suggest the need for integrated Christian elderly education and church elderly ministry, and there is a need for a study that suggests a curriculum that can be implemented in the field. Second, there are two educational objectives derived from Fowler's study of faith. One is to describe, analyze, and reconstruct the three elements that make up the content of faith: centers of value, image of powers, and central stories. Second, to explore vocation through a life of pilgrimage in response to the call to partnership with God. Third, autobiographical writing involves an approach based on the tradition of qualitative research and should be oriented toward teaching and learning principles based on descriptive, native, holistic, lived-experience, pathic, interpretive, and open-ended principles. Conclusions and Recommendations: Autobiographical writing will contribute to helping the elderly experiencing crises of despair and anxiety to integrate the meaning of their lives through the holistic expression of their thoughts and feelings, to helping socially isolated older adults to feel connected to society, and to helping them to envision and imagine the future through the present act of revealing their voice. It is hoped that autobiographical writing will increase the number of conversations through retrospection and confession of faith of the elderly.

• Smart Structures and Systems
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• v.34 no.2
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• pp.97-116
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• 2024

The standard l₁-norm regularization is recently introduced for impact force identification, but generally underestimates the peak force. Compared to l₁-norm regularization, l_p-norm (0 ≤ p < 1) regularization, with a nonconvex penalty function, has some promising properties such as enforcing sparsity. In the framework of sparse regularization, if the desired solution is sparse in the time domain or other domains, the under-determined problem with fewer measurements than candidate excitations may obtain the unique solution, i.e., the sparsest solution. Considering the joint sparse structure of impact force in temporal and spatial domains, we propose a general l_p-norm (0 ≤ p < 1) regularization methodology for simultaneous identification of the impact location and force time-history from highly incomplete measurements. Firstly, a nonconvex optimization model based on l_p-norm penalty is developed for regularizing the highly under-determined problem of impact force identification. Secondly, an iteratively reweighed l₁-norm algorithm is introduced to solve such an under-determined and unconditioned regularization model through transforming it into a series of l₁-norm regularization problems. Finally, numerical simulation and experimental validation including single-source and two-source cases of impact force identification are conducted on plate structures to evaluate the performance of l_p-norm (0 ≤ p < 1) regularization. Both numerical and experimental results demonstrate that the proposed l_p-norm regularization method, merely using a single accelerometer, can locate the actual impacts from nine fixed candidate sources and simultaneously reconstruct the impact force time-history; compared to the state-of-the-art l₁-norm regularization, l_p-norm (0 ≤ p < 1) regularization procures sufficiently sparse and more accurate estimates; although the peak relative error of the identified impact force using l_p-norm regularization has a decreasing tendency as p is approaching 0, the results of l_p-norm regularization with 0 ≤ p ≤ 1/2 have no significant differences.

• The Journal of Korean Academic Society of Nursing Education
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• v.1 no.1
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• pp.17-23
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• 1995

One of the biggest problems of Nursing Education in Korea is the division among nursing education programs of the last 3 and 4 years. To solve this problem, Nursing community must do variable trials to achieve the unity of a 4-year educational program. With this, we need to observe the phenomena and reality of the present 4-year nursing educational program that we have. The object of this study is to analyse and discuss that we have. The object of this study is to analyse and discuss the problems and future strategies of 4-year Nursing Baccalaureate program. 1. Problems as nursing department in Medical School. 1) Many 4-year nursing baccalaureate programs are operating under the medical school as nursing department. So the academic development in nursing department is unprogressive and is not approved as unique discipline. 2) The operating system between nursing and medical department are different even though they are in the same school. 3) Inequality between nursing and medical department : In many case, the nursing professor can not attend administraion committees to discuss the medical school's operation because of many differences between nursing and medical organization. 4) Weakness of the leadership and the student activities in nursing student : The nursing student involvement is usually passive because of the difference of curriculum, less number than medical students and the difference between 4-year and 6-year education program. 5) There is the obscurity of the relationship between department of nursing and other departments in whole university. 2. Problems in nursing itself 1) We need to reconstruct nursing discipline. We must change from the disease centered model to health centered model and life cycle centered model so that we can be distinguished from medicine. We also must change from hospital centered nursing to all population centered nursing, 2) The improvement of curriculum ; When the independent framework of nursing discipline become established, we need to improve the curriculum. 3) The education of clinical practice ; Most nursing school programs are divided into professors who are lecturing the theory and clinical teachers who are teaching the nursing technique in the clinic. So, what is needed in nursing discipline is that the professors have a dual position. In America, The professor is required to be a clinical specialist and to have his or her clinic so that the professor become a good role model, teach the clinical practice effectively, and give the student the practice field. 4) To extend fields of nursing : At first, the school nurse must become the school health educator, a real teacher. The nurse must establish and operate a childern's wellbeing center or nursery school, a disabled people's house or senile's wellbeing center, a mental health center, and a health promotion clinic for healthy people. 5) The name 'nursing department' need to be considered. When the focus is to be changed from the disease model to health improvement model, we take into consideration change 'nursing college', 'nursing department' and 'nursing profession' to 'health science college' or 'health wellbeing college'. 6) We must have highly qualified academic students. Each Nursing educational faculties must have the high qualified students through the development of nursing educational program and the increment of scholarship. The Korean Nurses Association and The Korean Clinical Nurses Association need to make an endeavor for the improvement of work condition and payment of clinical nurses of hospitals who consist of 70% of all nursing manpower. 3. Improvement Strategy 1) All nursing educational program must be changed 4-year program gradually. 2) Nursing department need to try to become nursing college. 3) We need to study many researches for improvement of the problem in nursing discipline and nursing education. We need more interdisciplinary researches, and we need to be granted for that research. 4) We need to have many seminars and workshops thoughout the whole country to expand a sense of nursing education. 5) Drawing up a policies plan for the nursing educational improvement : The Korean Nurses Association, The Korean Academic Nursing Association, Korea Nursing College and department President's Committee, and Korea Academic Society of Nursing Education must try for the development of nursing educational improvement and ask for government frame the policy to develop nursing education.

• Spatial Information Research
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• v.4 no.1
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• pp.21-42
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• 1996

The Anyang-cheon is one of the Han River tributaries in Seoul Metropolitan area. It is 35.1km long, has a basin area of 287km2 and touches seven cities of Kyounggi Province and part of Seoul. The purpose of this study were 1) to reconstruct the ancient stream network and to investigate the change of landuse in Anyang-cheon watershed between 1957 and 1991,2) to measure the change of the hydrologic ¬acteristics with urbanization, 3) to suggest the institutional solutions to reduce natural hazard as the area has urbanizedThe main results are as follows: 1.Anyang-cheon river basin has experienced the rapid urbanization and industrialization since 1957. Anyang-cheon stream network was oversimplified in the watershed. The total stream length decreased atributaries in the upper part of river basin have eliminated or buried undergrolmd in pipes. 2.Urbanization impacted to all of the area of Anyang-cht'On watershed. Urbanization in Anyang-cheon watershed corresponds to the large portion of flat area, especially flood - prone zone of river side, and the small portion of Greenbelt to constrain urban expantion in cities. 3.The urbanization of Anyang-cheon watershed produces fundamental changes in watershed hydrology. As infiltration is reduced by the creation of extensive pavement, concrete surface, and sewer pipe, runoff moves more quickly from upland to stream. As a result, runoff from the watershed is flashier, increasing flood hazardAs urban area continue to grow we will need to better utilize stream by protecting and enhancing stream systems.otecting and enhancing stream systems.tems.

• Cartoon and Animation Studies
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• s.37
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• pp.45-82
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• 2014

Comics and cartoons of superheroes in the West have adopted various semiotic systems and other art-forms, including their politico-socio-economic condition, and made parody of other popular texts, as well. Based on the idea of the development of superhero genre, this article focuses on how East Asian popular texts appropriate and reconstruct the genre, which was once considered the realization of American idea, by analyzing a series of TV animation (Japan, Sunrise,2011). Through the feature of parody with intertextuality, provides East Asian value and sensibility of characters as corporation-centered modern humans in capitalist society. This animation has similarity and difference, compared to that of Western superhero cartoons. It satires Western capitalist society and emphasizes Eastern family-oriented value. The performances of superheroes on TV represent the satire on Western style individualism and estimation through each one's achievement. It metaphorically criticizes the situation in which modern human falls into dependency on capital and media, and the capitalistic system in which public good is used for the method of private profit. emphasizes East Asian value of human and society, the cooperative relation for the success and maintenance of community by combining members of state and society through familial sensibility. Tiger functions as a spiritual leader in the group of superheroes who have been obsessed with competition for their own private purpose rather than public cause, Bunny and other colleagues are gradually influenced by Tiger's familial communicative style. emphasizes community-centered view and self-sacrificing sensibility as an international citizen to solve social pathology of modern world.

• Journal of The Korean Association of Information Education
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• v.5 no.1
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• pp.33-45
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• 2001

In order to adapt ourselves to the Informationalization Society of twenty-first century, it is required to have ability to find quickly the necessary information and solve the problem of our own. In the field of school, it should be educated to develop learner's ability that can cope with the Informationalization Society. When a learner can study in such direction, he or she will be able to plan the learning of his own as the subject of education, and develop his ability to solve the problem by collecting and examining various information. It is self-leading learning that can make education like this possible. Through computer, especially Web site, self-directed learning can develop can develop the individuality and creativity of learners. They can collect and utilize autonomously information and knowledge. To do such an education, the program that can work out self-directed learning is needed. Therefore the program I want to develop is to reconstruct the 'figure' part of mathematics in elementary school into five steps by utilizing Web site. In the first step is to learn the concept of various shape. This step enable learners to know what figure is and how it can be utilized in our real life. The second step of dot, line and angle makes it possible that learners can consolidate the foundation of the study about figure and recognize the relation between angle and figure. In the third step of plane figure, we can study how to calculate the relation of plane figures and the area of figure with various shapes by cutting and adding them. The fourth step is about congruence and symmetry. Learners can learn to know the figure in congruence, reduction and enlargement and how it is used in our real life. In the fifth step of solid figure, we can learn the relation among the plane figure, solid figure, the body of revolution, corn and pyramid etc. controling the speed of learning on the basis of his ability. In the process of the program, it is also possible to develop learner's ability of self-leading learning by solving the problem by himself. Because this program is progressed on the Web site, it is possible to learn anytime and anywhere. In addition to it, a learner can learn beyond the grade as well as do the perfect learning by controling the pace of learning on the basis of his ability. In the process of the program, it is also possible to develop learner's ability of self-leading learning by solving the problem by himself.