• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.1
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• pp.239-260
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• 2023

The underwater acoustic wireless communication networks are generally formed by the different autonomous underwater acoustic vehicles, and transceivers interconnected to the bottom of the ocean with battery deployed modems. Orthogonal frequency division multiplexing (OFDM) has become the most popular modulation technique in underwater acoustic communication due to its high data transmission and robustness over other symmetrical modulation techniques. To maintain the operability of underwater acoustic communication networks, the power consumption of battery-operated transceivers becomes a vital necessity to be minimized. The OFDM technology has a major lack of peak to average power ratio (PAPR) which results in the consumption of more power, creating non-linear distortion and increasing the bit error rate (BER). To overcome this situation, we have contributed our symmetry research into three dimensions. Firstly, we propose a machine learning-based underwater acoustic communication system through long short-term memory neural network (LSTM-NN). Secondly, the proposed LSTM-NN reduces the PAPR and makes the system reliable and efficient, which turns into a better performance of BER. Finally, the simulation and water tank experimental data results are executed which proves that the LSTM-NN is the best solution for mitigating the PAPR with non-linear distortion and complexity in the overall communication system.

• Journal of Korean Academy of Nursing
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• v.30 no.4
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• pp.1035-1044
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• 2000

The purpose of this study was to develop and evaluate an internet based program for nursing informatics. The course subject, Nursing Informatics, was made by a computerized instructional module using the internet. The program was developed after taking into consideration the level of competence and knowledge in the subjects. It was based on 10 steps of the CAI module developed by Alessi and Trollip. The subjects consisted of 76 junior nursing students taking a Nursing Informatics course. Two sets of questionnaires were used for this study. First, a questionnaire was administered to 76 students to collect general information on their experience while using computers and the internet. Secondly, another questionnaire was administrated to 76 students after they took the course. They were asked to evaluate the program in terms of easiness of use, precision of contents, freshness of contents, motivation in learning, effectiveness of learning, enhancement of communication, precision of screen, and interest in the contents. IDs and passwords were given to the students. The students were asked to write their IDs and passwords when they connected to Nursing Informatics (http://hallym.ac.kr/~yhyom/ inform.html). They were led the menu page which was categorized into 8 icons (i. e., syllabus, lecture notes, quick test, Q & A board, assignment, on-line test, related web sites and mailing lists) after confirming their IDs and passwords. The students' responses were very positive. This program was a very useful in increasing the effectiveness of learning and motivation in the students. Suggest to be use for other nursing courses.

• Journal of Korean Academy of Nursing Administration
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• v.20 no.2
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• pp.227-236
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• 2014

Purpose: This study was designed to develop and evaluate the a web-based simulation program on patient rights education using integrated decision making model into values clarification for nurse students. Methods: The program was designed based on the Aless & Trollip model and Ford, Trygstad-Durland & Nelms's decision model. Focus groups interviews, surveys on learning needs for patient rights, and specialist interviews were used to develop for simulation scenarios and decision making modules. The simulation program was evaluated between May, 2011 and April, 2012 by 30 student nurses using an application of the web-based program evaluation tools by Chung. Results: Simulation content was composed of two scenarios on patient rights: the rights of patients with HIV and the rights of psychiatric patients. It was composed of two decision making modules which were established for value clarifications, behavioral objective formations, problems identifications, option generations, alternatives analysis, and decision evaluations. The simulation program was composed of screens for teacher and learner. The program was positively evaluated with a mean score of $3.14{\pm}0.33$. Conclusion: These study results make an important contribution to the application of educational simulation programs for nurse students' behavior and their decision making ability in protecting the patient rights.

• Journal of the Korean earth science society
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• v.22 no.2
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• pp.89-95
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• 2001

The purposes of the study are (1) to develop a Computer-Assisted Instruction (CAI) program to deal with middle school students' misconceptions on the concept of atmospheric pressure, and (2) to investigate the effects of the CAI on students' achievement and conceptual change. The findings of the study are as follows: (1) Misconceptions about atmospheric pressure found are similar to the ones identified in earlier studies, (2) A CAI program on atmospheric pressure was developed based on the students' misconceptions identified, and (3) The instruction using CAI program has very positive effects on students' science achievement and conceptual change.

• Korean Journal of English Language and Linguistics
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• v.1 no.2
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• pp.227-242
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• 2001

It is noted that although the current state of development of web-based English education (hereafter referred to as WBEE) might not meet the criteria some educators have set for themselves in the field, students certainly seem to prefer studying in a web-based and computer-assisted learning environment. This kind of demand is fueling the drive to develop more suitable variations of WBEE. In order for WBEE to work out, a teacher should be a multifunctional type of instructor handling responsibilities such as the role of scriptwriter to create text, act as technician for the sound mixing and recording, preside over online chat rooms and discussion boards, and finally, as webmaster to maintain the site and supervise all academic/ clerical work related to the course. Therefore, it is suggested that WBEE be accompanied by a small personnel to divide the labor and lessen the burden on the actual teacher. Finally, it is noted that the traditional relationship between students and teacher may no longer be sustainable since WBEE does not provide the face-to-face style of class discussion and office hours in its current form. Until the technology is fully developed to compensate for these kinds of differences, it is an immediate challenge to provide other more compelling reasons for students to participate in WBEE.

• Journal of Korean Clinical Nursing Research
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• v.22 no.1
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• pp.99-108
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• 2016

Purpose: This study aims to develop Tablet PC-based multimedia educational contents on the procedures from surgery preparation to recovery for hospitalized patients who are going to undergo thoracic surgery and their families. Methods: The educational contents were created based on literature review and a survey of needs in patients and their families who were admitted to a hospital in Seoul from Dec. 2013 to May 2014. The contents were developed in conjunction with a film production company. The educational materials including texts, images, sounds, and videos were developed appling the ADDIE (analysis, design, development, implementation, and evaluation) model. Results: Two multimedia educational contents were developed for the patients with coronary artery bypass graft or lung surgery. Each content consisted of six subdivisions of self-learning for 20 minutes. The developed educational contents were completed after testing content validity by 30 medical experts. Conclusion: This study recommends that the Tablet PC-based educational contents for thoracic and cardiovascular patients and their families be used in general wards and intensive care units to relieve their anxiety before surgery and reduce postoperative complications.

• Journal of Korean Academy of Nursing
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• v.40 no.4
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• pp.463-472
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• 2010

Purpose: This study was done to develop a web-based education program for nurses working in nursing homes. The focus was on the rights of older adults. Methods: The program was designed based on the Network-Based Instructional System Design (NBISD) model and was operated and evaluated between July 2007 and June 2008. Results: Out of nursing records of 40 residents from a nursing home, the final 7 cases were deducted through classification using the Resource Utilization Group (RUG)-III. The data on needs for education was collected from 28 nurses working in 15 nursing homes located in Seoul and Gyeonggi Province, who agreed to complete a self-report questionnaire. A comprehensive review of the literature and two focus groups interviews were used to search for risk factors and guidelines for protection of human rights. The education program was developed based on Kolb's experiential learning model and composed of 5 units, which included content on types of human rights and rights to death with dignity, elder abuse, physical liberty, and self-determination. The program was positively evaluated showing a score of 3.35 (SD=0.37) out of 4. Conclusion: The educational program developed in this study should promote nurses' sensitivity to the rights of elders and improve nurses' behaviors in protecting the rights of elders residing in nursing homes.

• ETRI Journal
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• v.42 no.5
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• pp.761-772
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• 2020

This paper presents an automatic proficiency assessment method for a non-native Korean read utterance using bidirectional long short-term memory (BLSTM)-based acoustic models (AMs) and speech data augmentation techniques. Specifically, the proposed method considers two scenarios, with and without prompted text. The proposed method with the prompted text performs (a) a speech feature extraction step, (b) a forced-alignment step using a native AM and non-native AM, and (c) a linear regression-based proficiency scoring step for the five proficiency scores. Meanwhile, the proposed method without the prompted text additionally performs Korean speech recognition and a subword un-segmentation for the missing text. The experimental results indicate that the proposed method with prompted text improves the performance for all scores when compared to a method employing conventional AMs. In addition, the proposed method without the prompted text has a fluency score performance comparable to that of the method with prompted text.

• Annual Conference on Human and Language Technology
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• 2010.10a
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• pp.3-8
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• 2010

본 연구에서는 일련의 연구에서 수집된 영작문 오류 유형의 정제된 자료를 토대로 연관 규칙을 생성하고, 학습을 통해서 효용성이 검증된 연관 규칙을 활용해서 영작문 데이터의 형태 통사 오류를 자동으로 탐지한다. 영작문 데이터에서 형태 통사 오류를 찾아내는 작업은 많은 시간과 자원이 소요되는 작업이므로 자동화가 필수적이다. 기존의 연구들이 통계적 모델을 활용한 어휘적 오류에 치중하거나 언어 이론적 틀에 근거한 통사 처리에 집중하는 반면에, 본 연구는 데이터 마이닝을 통해서 정제된 데이터에서 연관 규칙을 생성하고 이를 검증한 후 형태 통사 오류를 감지한다. 이전 연구들에서는 이론적 틀에 맞추어진 규칙 생성이나 언어 모델 생성을 위한 대량의 코퍼스 데이터와 같은 다량의 지식 베이스 생성이 필수적인데, 본 연구는 적은 양의 정제된 데이터를 활용한다. 영작문 오류 유형의 형태 통사 연관 규칙을 생성하기 위해서 Apriori 알고리즘을 활용하였다. 알고리즘을 통해서 생성된 연관 규칙 중 잘못된 규칙이 생성될 가능성이 있으므로, 상관성 검정, 코사인 유사도와 같은 규칙 효용성의 통계적 검증을 활용해서 타당한 규칙만을 학습하였다. 이를 통해서 축적된 연관 규칙들을 영작문 오류를 자동으로 탐지하는 실험에 활용하였다.

• Journal of Information Processing Systems
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• v.17 no.1
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• pp.178-190
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• 2021

Alzheimer's disease (AD) is an insidious and degenerative neurological disease. It is a new topic for AD patients to use magnetic resonance imaging (MRI) and computer technology and is gradually explored at present. Preprocessing and correlation analysis on MRI data are firstly made in this paper. Then kernel principal component analysis (KPCA) is used to extract features of brain gray matter images. Finally supervised classification schemes such as AdaBoost algorithm and support vector machine algorithm are used to classify the above features. Experimental results by means of AD program Alzheimer's Disease Neuroimaging Initiative (ADNI) database which contains brain structural MRI (sMRI) of 116 AD patients, 116 patients with mild cognitive impairment, and 117 normal controls show that the proposed method can effectively assist the diagnosis and analysis of AD. Compared with principal component analysis (PCA) method, all classification results on KPCA are improved by 2%-6% among which the best result can reach 84%. It indicates that KPCA algorithm for feature extraction is more abundant and complete than PCA.