• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.37 no.2
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• pp.141-147
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• 2024

The measurement of strain under an electric field has been widely employed to comprehend the fundamental principles of electro-mechanical responses in ferroelectric, piezoelectric, and electrostrictive materials. In particular, understanding the strain properties of piezoelectric materials in response to electrical stimulation is crucial for researching and developing components such as piezoelectric actuators, acoustic devices, and ultrasonic generators. This tutorial paper introduces the components and operational principles of the linear variable differential transducer (LVDT), a widely used displacement measurement device in various industries. Additionally, we present the configuration of an experimental setup using LVDT to measure the strain characteristics of ferroelectric, piezoelectric, or electrostrictive materials under the application of an electric field. This paper includes simple measurement results and analyses obtained through the LVDT experimental setup, providing valuable information on research methods for the electro-mechanical interactions of various materials.

• Korean Journal of Radiology
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• v.22 no.3
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• pp.442-453
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• 2021

Artificial intelligence (AI) will likely affect various fields of medicine. This article aims to explain the fundamental principles of clinical validation, device approval, and insurance coverage decisions of AI algorithms for medical diagnosis and prediction. Discrimination accuracy of AI algorithms is often evaluated with the Dice similarity coefficient, sensitivity, specificity, and traditional or free-response receiver operating characteristic curves. Calibration accuracy should also be assessed, especially for algorithms that provide probabilities to users. As current AI algorithms have limited generalizability to real-world practice, clinical validation of AI should put it to proper external testing and assisting roles. External testing could adopt diagnostic case-control or diagnostic cohort designs. A diagnostic case-control study evaluates the technical validity/accuracy of AI while the latter tests the clinical validity/accuracy of AI in samples representing target patients in real-world clinical scenarios. Ultimate clinical validation of AI requires evaluations of its impact on patient outcomes, referred to as clinical utility, and for which randomized clinical trials are ideal. Device approval of AI is typically granted with proof of technical validity/accuracy and thus does not intend to directly indicate if AI is beneficial for patient care or if it improves patient outcomes. Neither can it categorically address the issue of limited generalizability of AI. After achieving device approval, it is up to medical professionals to determine if the approved AI algorithms are beneficial for real-world patient care. Insurance coverage decisions generally require a demonstration of clinical utility that the use of AI has improved patient outcomes.

• Journal of Korean Public Health Nursing
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• v.11 no.2
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• pp.141-151
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• 1997

As concerns about dementia patients increase gradually in society, the nursing of them becomes more and more important. For intervening in dementia patients effectively, the most fundamental thing is to understand their characteristics and to increase the ability of assessing them. The assessment data supply us with the foundations of Nursing diagnosis and nursing plan. The reaseons why the assessment data are especially important to dementia patients are as follows; First, dementia patients have great differences among them in intellectual, physical ability. And their condition varies from time to time. Second, the intervention without planning results in the deficiency of consistence, and it rather embarrasses and makes dementia patients uneasy. Third, nursing of dementia patients requires participation of multi-disciplinary team because of characteristics of that disease. The development of an unitary assessment tool is essential for all members of the team to have close relations between them and care for dementia patients. Fully understanding the importance of assessment data, this study investigate the content to be included in the assessment before developing assessment tools to be used in community. It points out that the assessment should include the informations about patients, their family, and main care-giver. And it sets up items that can supply with detailed information on each person. In the future it is necessary to transform the contents of this study to more concrete items and develope the assessment tools for dementia patients. And recording paper for follow up should be supplemented to check any changes in family caring for dementia patients and describe the changes in detail. To make assessment tools is one of the fundamental works in controlling dementia patients. Therefore the official assessment tools should be provided as soon as possible. This study aimed at presenting the guiding principles for developing that assessment tools.

• Journal of Computing Science and Engineering
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• v.1 no.1
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• pp.1-30
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• 2007

In this paper we have provided an extensive survey of the databases and other resources related to the current research in bioinformatics and the issues that confront the database researcher in helping the biologists. Initially we give an overview of the concepts and principles that are fundamental in understanding the basis of the data that has been captured in these databases. We briefly trace the evolution of biological advances and point out the importance of capturing data about genes, the fundamental building blocks that encode the characteristics of life and proteins that are the essential ingredients for sustaining life. The study of genes and proteins is becoming extremely important and is being known as genomics and proteomics, respectively. Whereas there are numerous databases related to various subfields of biology, we have maintained a focus on genomic and proteomic databases which are the crucial stepping stones for other fields and are expected to play an important role in the future applications of biology and medicine. A detailed listing of these databases with information about their sizes, formats and current status is presented. Related databases like molecular pathways and interconnection network databases are mentioned, but their full coverage would be beyond the scope of a single paper. We comment on the peculiar nature of the data in biology that presents special problems in organizing and accessing these databases. We also discuss the capabilities needed for database development and information management in the bioinformatics arena with particular attention to ontology development. Two research case studies based on our own research are summarized dealing with the development of a new genome database called Mitomap and the creation of a framework for discovery of relationships among genes from the biomedical literature. The paper concludes with an overview of the applications that will be driven from these databases in medicine and healthcare. A glossary of important terms is provided at the end of the paper.

• Journal of Korean Association for Spatial Structures
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• v.5 no.2 s.16
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• pp.73-79
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• 2005

Tensegrity is a relatively new structural system based on the use of continuous tension-discontinuous compression. Of course, a much more detailed structural investigation would be necessary, but at least in order to achieve the intended purpose, it is essential to understand the structural principles and the fundamental forces of tensegrity. Once this point is established, the applications of them to architecture are described, as well as the characteristics of these structures. Then, in spite of the controversial definitions to explain these systems, several examples of tensegrity prototypes or modules constructed in iESD(Institute of Environmental Structure Design) are presented to illustrate the feasibility of tensegrity as a lightweight structure. In this work, consequently, the reformability and application of tensegrity modules have also been researched in architecture, after the patterns of basic module as well as fundamental definition are introduced.

• Journal of Engineering Education Research
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• v.8 no.1
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• pp.20-30
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• 2005

Recently, a new education paradigm 'Self-directed Learning' has attracted considerable attention. Problem-Based Learning (PBL) has been recognized as methodology to help students expand scientific thinking and knowledge. improve applicability, develope critical knowledge, and creatively solve problems. There have been significant efforts to develope PBL-based courses in mechanical engineering. A new PBL-based, multi-disciplinary course 'Product Dissection and Design Reasoning' has been developed in this paper. The course examines the way in which products and machines work and is intended to show freshman or sophomore level students how fundamental physical principles relate to engineering practice through hands-on dissection experience : thus, the course emphasizes the importance of knowledge of the fundamental physics for design reasoning. The primary role of this course is to develop creative design manpower. This paper describes the philosophy and content of this course and presents results from one year of development.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.3
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• pp.38-48
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• 2017

ISO 9001 Quality Management Systems-Requirements has been revised in 2015. It has been updated four times since its publication in 1987. It is the most widely used International Standard in the world. There are over one million companies and organizations in over 170 countries certified to ISO 9001 from an ISO survey. Organizations are supposed to be certified to this new version by late 2018. The key changes in ISO 9001:2015 are to establish a High Level Structure (HLS) and focus on Risk-Based Thinking (RBT). Risk-Based Thinking means the process approach to decide how risk is addressed in establishing the processes to improve process outputs and prevent undesirable results. It pursues process planning and controls based on risks so that organizations can improve the effectiveness of the quality management system. It maintains and manages a Quality Management System that inherently addresses risks and meets objectives. In this article we firstly attempt to explain how to understand the fundamental concept of Risk-Based Thinking which is a systematic approach to consider risks rather than treating prevention as a separate component of a Quality Management System. We comment on the detailed requirements that contain risks in ISO 9001:2015 clauses. We also summarize recent advances on the risk assessment and management in line with ISO 31000:2009 Risk Management-Principles and Guidelines. We finally propose the practical risk management procedures for implementing ISO 9001:2015 with an emphasis on RBT. This article would contribute to help quality managers and practitioners convert to ISO 9001:2015.

• Bulletin of the Society of Naval Architects of Korea
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• v.13 no.1
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• pp.1-9
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• 1976

Using the computer programs for calculation of natural vibrations of ship's hull developed by the authors et al., an investigation into influences of various parameters on the accuracy of calculation was done through example calculations of a 30,000 DWT petroleum products carrier M/S Sweet Brier built by Korea Shipbuilding and Engineering Corporation. The methodical principles employed for the computer program development are as follows; (a) the ship system is reduced to an equivalent discrete elements system conforming to Myklestad-Prohl model, (b) the problem formulation is of transfer matrix method, and (c) to obtain solutions an extended $G\ddot{u}mbel's$ initial value method is introduced. The scope of the investigation is influences of number of discrete elements, choice of significant system parameters such as rotary inertia, bending stiffness and shear stiffness, and simplification of distributions of added mass and stiffness as trapezoidal ones referred to those of midship section on the calculation accuracy. From the investigation the followings are found out; (1) To obtain good results for the modes up to the seven-noded thirty or more divisions of the hull is desirable. For fundamental mode fifteen divisions may give fairly good results. (2) The influence of rotary inertia is negligibly small at least for the modes up to the 5- or 6- noded. (3) In the case of assuming either bending modes or shear modes the calculation results in considerably higher frequencies as compared with those based on Timoshenko beam theory. However, the calculation base on the slender beam theory surprisingly gives frequencies within 10% error for fundamental modes. (4) It is proved that to simplify distributions of added mass and stiffness as trapezoidal ones referred to those of midship section is a promising approach for the prediction of natural frequencies at preliminary design stage; provided good accumulation of data from similar type ships, we may expect to obtain natural frequencies within 5% error.

• The Mathematical Education
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• v.49 no.2
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• pp.175-198
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• 2010

To understand natural or social phenomena, we need various information, knowledge, and thought skills. In this context, mathematics and sciences provide us with excellent tools for that purpose. This explains the reasons why there is always significant emphasis on mathematics and sciences in school education; some of the general goals in school education today are to illustrate physical phenomena with mathematical tools based on scientific consideration, to encourage students understand the mathematical concepts implied in the phenomena, and provide them with ability to apply what they learned to the real world problems. For the mentioned goals, we extract six fundamental principles for the integrated mathematics and science education (IMSE) from literature review and suggest a instructional design model. This model forms a fundamental of a case study we performed to which the IMSE was applied and tested to collect insights for design and practice. The case study was done for 10 students (2 female students, 8 male ones) at a coeducational high school in Seoul, the first semester 2009. Educational tools including graphic calculator(Voyage200) and motion detector (CBR) were utilized in the class. The analysis result for the class show that the students have successfully developed various mathematical concepts including the rate of change, the instantaneous rate of change, and derivatives based on the physical concepts like velocity, accelerate, etc. In the class, they described the physical phenomena with mathematical expressions and understood the motion of objects based on the idea of derivatives. From this result, we conclude that the IMSE builds integrated knowledge for the students in a positive way.

• Philosophy of Education
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• no.46
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• pp.45-70
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• 2012

The purpose of this study is researching on educational difficulty in the history of western education. In other words, the goal and significance of this paper lies in knowing the essential meaning of education based on the norms of difficulty. The major method for this study is hermeneutical-anthropological pedagogy. My fundamental claim is the following: the essential nature of teaching is difficulty at any instructional condition and situations. Such a discrete idea was clearly identified and confirmed in the process of pedagogical anthropology. That is, through the consciousness of educational difficulty and critical review for the history of western education, I can cleary define the concept of educational difficulty. Educational difficulty was various ways for understanding by all audiences. Namely, various formulars were developed for understanding it according to the age, cultures, nations, ideology, etc.. But there are continuous characters on the way for understanding on educational difficulty. The results on research are as followings. In the primitive age, fundamental difficulty of education lies in the initiation ceremony. At the classical ancient time, the purpose of education was 'Politai' with politike arete, in this educational conditions, instruction have a complex dimension politically as well as psychologically. At the medieval age, educational difficulty lies in the 'Askese' for instructional methods. In the modern and conventional age, educational difficulty is more and more complex and confused on goals, methods, evaluations, etc.. Most of all, the major or key concept of educational difficulty in this world is the conflict between the two instructional principles, that is, objectivism and constructivism in education. At now, the schoolworks for instruction over all educational situations and conditions have a difficulty of traditional as well conventional dilemma. In conclusion, educational difficulty have formal, natural, original attribute and it is general and universal phenomenon.