• 한국비블리아학회지
• /
• 제23권4호
• /
• pp.5-24
• /
• 2012

본 연구는 주제어기반 분류의 발전 과정 및 현황을 종합적으로 분석하고 그 기능과 유형을 명확히 함으로써 주제어기반 분류의 분류론적 개념을 정립하고, 향후 분류체계로써의 정착 및 발전을 위한 제안을 하고자 하는 목적을 가지고 있다. 이를 위하여 본 연구는 1937년부터 현재에 이르기까지 발표된 주제어기반 분류의 필요성에 대한 논의를 수집하여 분석하고, 주제어기반 분류에 해당하는 다양한 사례를 수집하여 그 명칭과 유형을 분석하였다. 또한 분류로써의 주요 기능 수행력을 기존의 문헌분류와 비교하고, 분류와 주제명표목과의 비교 분석을 통해 지식조직체계로써의 기능과 특성을 밝히고자 하였다. 이러한 분석의 결과, 주제어기반 분류는 구체적인 기능 정의, 유형, 사용되는 정보환경, 지식조직체계간의 관계성 등을 면밀히 고려함으로써 그 분류론적 개념과 기능을 명확히 정의할 수 있음을 밝혔고, 향후 분류체계로써의 정착과 발전을 위한 발전방안을 제시하였다.

• Communications for Statistical Applications and Methods
• /
• 제20권3호
• /
• pp.235-240
• /
• 2013

Generalized linear mixed models(GLMMs) are frequently used for the analysis of longitudinal categorical data when the subject-specific effects is of interest. In GLMMs, the structure of the random effects covariance matrix is important for the estimation of fixed effects and to explain subject and time variations. The estimation of the matrix is not simple because of the high dimension and the positive definiteness; subsequently, we practically use the simple structure of the covariance matrix such as AR(1). However, this strong assumption can result in biased estimates of the fixed effects. In this paper, we introduce Bayesian modeling approaches for the random effects covariance matrix using a modified Cholesky decomposition. The modified Cholesky decomposition approach has been used to explain a heterogenous random effects covariance matrix and the subsequent estimated covariance matrix will be positive definite. We analyze metabolic syndrome data from a Korean Genomic Epidemiology Study using these methods.

• Journal of Information Processing Systems
• /
• 제15권3호
• /
• pp.500-519
• /
• 2019

The blooming of social media has simulated interest in sentiment analysis. Sentiment analysis aims to determine from a specific piece of content the overall attitude of its author in relation to a specific item, product, brand, or service. In sentiment analysis, the focus is on the subjective sentences. Hence, in order to discover and extract the subjective information from a given text, researchers have applied various methods in computational linguistics, natural language processing, and text analysis. The aim of this paper is to provide an in-depth up-to-date study of the sentiment analysis algorithms in order to familiarize with other works done in the subject. The paper focuses on the main tasks and applications of sentiment analysis. State-of-the-art algorithms, methodologies and techniques have been categorized and summarized to facilitate future research in this field.

• 응용통계연구
• /
• 제23권4호
• /
• pp.715-724
• /
• 2010

재발 사건 자료(recurrent event data)는 연구 대상이 같은 종류의 사건을 여러 번 경험할 때 발생되는 자료 형태이다. 재발 사건간에 연관관계를 위해 프레일티가 사용된다. 프레일티 효과는 랜덤효과의 한 형태로 개인별 특성을 표현하기 위해 생존 분석에서 널리 적용되어 왔다. 본 논문에서는 이러한 개인별 효과가 시간에 따라 변할 수 있음을 가정하여 시간 가변 프레일티를 적용한다. 본 논문에서는 적용 사례로 범죄 재범 자료를 분석한다. 특히 일부 관측 대상들은 일정 기간 동안 연구에서 제외되는 불연속성을 경험하게 되며 이는 위험그룹(risk group)의 새로운 정의가 필요하다. 모수 추정을 위해 조각 상수 위험 함수가 사용되며 EM 알고리즘이 적용된다.

• 한국환경교육학회지:환경교육
• /
• 제11권2호
• /
• pp.1-13
• /
• 1998

The purpose of this study is to investigate thel present situation and to analyze the needs and problems of the $\ulcorner$Environment$\lrcorner$ subject in secondary school of the current 6th curriculum in Korea and to indicate the directions of improvement environmental education. The first step of this research was to review the related literature and the result indicated that the number of secondary schools that selected $\ulcorner$environment$\lrcorner$ subject and the teachers who have $\ulcorner$environment$\lrcorner$ certification of a second-major has increased yearly but it shows much difference by regions. The second step was questionnaire surveys on 60 $\ulcorner$Environment$\lrcorner$ teachers in secondary school. According to the survey, 65% of teachers are not certificated and 50% of teachers have no self-confidence of teaching. And most of teachers thought it was difficult to select the modules out of textbook and teachers had difficulties such as the lack of appropriate reference materials and instructive experience of their own instructive experience of active researches. The third step was the questionnaire survey on a students group(606) learning the $\ulcorner$environment$\lrcorner$ subject and a students group(621) without the $\ulcorner$environment$\lrcorner$ subject in secondary school. The group learning $\ulcorner$environment$\lrcorner$ subject showed significantly higher scores than those of the group without $\ulcorner$environment$\lrcorner$ subject in most items. And among the students having $\ulcorner$environment$\lrcorner$ subject, the first year students achieved the highest score, and it revealed that the teaching was most effective to them. The suggestions based on the results of this study are as follows. First, the uncertifiable teachers currently teaching $\ulcorner$environment$\lrcorner$ subject should be given priority to the second-major certificate training program ; which are diverse in contents according to differences of majors and levels. Second, specific and practical re-training programs for the certificated teachers teaching the subject are needed. Third, considerable and continual adjustment of the textbook yearly is required in addition to regular curriculum amendment. Fourth, the more efficient and actual teaching.learning methods of $\ulcorner$environment$\lrcorner$ subject education that can attract students' interest must be developed. Fifth, it is most desirable to have first year students select the subject.

• 한국치위생학회지
• /
• 제21권5호
• /
• pp.639-644
• /
• 2021

Objectives: The purpose of this study was to analyze the factors that affected the number of citations for articles published in the Journal of Korean Society of Dental Hygiene based on previous studies. Methods: Information on papers including the number of citations was collected using a web crawling technique. The effect of the number of author keywords, the number of Medical Subject Headings (MeSH) keywords, MeSH match rate, abstract word count and keyword-abstract ratio on the number of citations was analyzed by multiple regression analysis. Results: The use of the MeSH keyword did not have a significant effect on the number of citations. Among the other factors, only the keyword-abstract ratio was statistically significant. Conclusions: Select a topic of constant interest in the field, write the title in detail using colons or asterisks if necessary, and do not repeat the words used in the title in keywords. Select specific keywords deeply related to the topic. In particular, choice words or phrases that are frequently used in the abstract. If the MeSH keyword selection contradicts the previous strategies, boldly give up the MeSH keyword.

• 한국환경교육학회지:환경교육
• /
• 제12권1호
• /
• pp.40-63
• /
• 1999

As the environmental problems are recognized as daily problems in our lives, not as issues of those who are engaged in specific professional fields, the interest in environmental education is increasing gradually. The environmental education is the one that studies the environment and its problems and seeks the solutions for them. This paper deals with how the Korean subject will include environmental education. The environmental problems are already dealt with in the Korean textbooks according to the 6th curriculum for the Korean subject. A noticeable fact is that those textbooks connect the skills for language skills with environmental education. That is, the textbooks try to improve 4 language skills (speaking, listening, reading, and writing) with the Korean data related to environment, which can be the most practical means. This tendency will be also reflected in the 7th curriculum for the Korean subject, and the means will be taken by which environmental education will be able to be implemented more effectively through a variety of learning activities. In case of speaking and listening, learning activities such as speaking of, listening to, or discussing the contents concerning environmental problems can be recommended. In case of reading and literature, learning activities such as reading articles or works concerning environmental problems. Through these learning activities the Korean education will be able to achieve the goal in the fields of knowledge, information, and autonomy or attitudes which are the goals of environmental education. If the contents of the Korean curriculum are described in detail, it can be known that the Korean subject have someting to do with knowledge, skills, and recognition more deeply. In the methods In obtain information and knowledge, it will be desirable to recognize knowledge and information indirectly through various reading data rather than to recognize knowledge and information directly. Or it will be desirable to increase the sensitivity about environmental problems through literary works. For this environmental education in the above, we need to utilize discussion or presentation-oriented leaching and learning in the Korean education. Also we need to approach environmental problems by using various teaching media. We need to emphasize the education in the affective domain, especially through expression of emotions. guidance of reactions, internalization, personification, and so on.

• 한국통계학회:학술대회논문집
• /
• 한국통계학회 2004년도 학술발표논문집
• /
• pp.243-248
• /
• 2004

The timings of two successive events of interest may not be measurable, instead it may be right censored or interval censored; this data structure is called doubly censored data. In the study of HIV, two such events are the infection with HIV and the onset of AIDS. These data have been analyzed by authors under the assumption that infection time and induction time are independent. This paper investigates the regression problem when two events arc modeled to allow the presence of a possible relation between two events as well as a subject-specific effect. We derive the estimation procedure based on Goetghebeur and Ryan's (2000) piecewise exponential model and Gauss-Hermite integration is applied in the EM algorithm. Simulation studies are performed to investigate the small-sample properties and the method is applied to a set of doubly censored data from an AIDS cohort study.

• 한국정밀공학회지
• /
• 제9권4호
• /
• pp.13-21
• /
• 1992

Standards concerning the determination of positioning accuracy and repeatability of numerically controlled(NC) machine tools have been published relentlessly over the last 20 years. Since the publication in 1988 of the International Standard 230-2 there has been a pronounced move, both at national and international standards level, to embrace further test procedures for a complete machine tool performance assessment. For example, measurements of angular (pitch, roll, and yaw) and straightness errors along linear axes are now commonplace and complement the existing positioning accuracy and repeatablity tests. More recently the subject of circularity evalutaion has also gained considerable interest. Here dynamic tests, using a kinematic ballbar or circular masterpiece, give an instant overview of the contouring ability of the machine in two axes at specific feedrates. This information is extremely important in optimising machining accuracy. This paper describes moves to complete the machine calibration package in national and international standardis- ation for the assessment of machine tool performance.

• International Journal of Computer Science & Network Security
• /
• 제23권7호
• /
• pp.193-201
• /
• 2023

Abstraction is the cornerstone of ideal software engineering (SWE). This paper discusses a problem of forming reasonable generalizations, representations and descriptions in various software development processes through the prism of poor-quality (rash, unconsidered, uncertain and harmful) abstractions. To do this, emphasis is made on an induced strategic connection between the required abstraction and its compact specific formulation based on existing research and the author's introspective experience. A software aim point and characteristic preservation of the solution integrity is the subject of the best formulation and a program module or code associated with it. Moreover, a personal attitude expressed by personal interest, motivation and creativity, is proclaimed to be a fundamental factor in successful software development.