• Journal of the Korean Mathematical Society
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• v.54 no.3
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• pp.847-865
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• 2017

For a finite or an infinite set X, let $2^X$ be the power set of X. A class of simple graph, called strong Boolean graph, is defined on the vertex set $2^X{\setminus}\{X,{\emptyset}\}$, with M adjacent to N if $M{\cap}N={\emptyset}$. In this paper, we characterize the annihilating-ideal graphs $\mathbb{AG}(R)$ that are blow-ups of strong Boolean graphs, complemented graphs and preatomic graphs respectively. In particular, for a commutative ring R such that AG(R) has a maximum clique S with $3{\leq}{\mid}V(S){\mid}{\leq}{\infty}$, we prove that $\mathbb{AG}(R)$ is a blow-up of a strong Boolean graph if and only if it is a complemented graph, if and only if R is a reduced ring. If assume further that R is decomposable, then we prove that $\mathbb{AG}(R)$ is a blow-up of a strong Boolean graph if and only if it is a blow-up of a pre-atomic graph. We also study the clique number and chromatic number of the graph $\mathbb{AG}(R)$.

• Journal of the Korean Institute of Educational Facilities
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• v.14 no.2
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• pp.16-24
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• 2007

The study is intended to analyze the tendency of the remodeling for the high schools in Seoul, with the potential challenges thereof, determining the principle for the remodeling projects in the days to come. To that end, the analysis to identify the school facilities in a bid to accommodate the current curriculum was conducted, along with the case study on remodeling projects. The $7^{th}$ curriculum demands for a significant change in school facilities. The number of student in a class that has been on the decline, despite of steady increase in number of schools, and the population getting concentrated in Seoul and its suburbs have resulted in an increase in number of class. Consequently, more investment in the facility, rather than improving a substantial education environment, has been made. The study, thus, is aimed at identifying the facility of the high school required by the $7^{th}$ curriculum, as well as implementing a fact-finding investigation into the remodeling works far high schools in Seoul so as to come up with the guideline for remodeling projects.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.15 no.1
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• pp.6-13
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• 2008

Purpose: This research was conducted to identify major factors that influence competency for nursing students in basic nursing skills. Method: Data were collected by questionnaires from 290 first year students in one college of nursing. The instrument tools included motivation for admission to nursing, concern about fundamentals of nursing, perceived importance of fundamentals of nursing, level of active participation in fundamentals of nursing, number of times to use open Lab, Lab class satisfaction, self-efficacy, self-evaluation and student attitude. Results: There was no significant correlation between competency in basic nursing skills and motivation for admission to nursing, concern about fundamentals of nursing, perceived importance of fundamentals of nursing, or number of times to use open Lab. Competency in basic nursing skill in these students showed a significantly positive correlation to Lab class satisfaction, self-efficacy, self-evaluation, student attitude and level of active participation in fundamentals of nursing. The major factors that influenced competency in basic nursing skills for nursing students were student attitude, self-efficacy and number of times to use open Lab. These factors explained 15.5% of the variance in competency. Conclusion: Basic nursing skill practice education programs should be developed to improve self-efficacy and active participation.

• The Korean Journal of Community Living Science
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• v.15 no.2
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• pp.43-54
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• 2004

The purpose of this study is to examine the job satisfaction of teachers in urban and rural day care centers. The subjects of this study were 134 teachers in urban(n=68) and rural(n=66) areas. Participants completed an early childhood job satisfaction survey. The statistics used for this data were t-test, one-way ANOVA (Duncan's test), and multiple regression analysis. The study showed significant differences between urban and rural teachers' job satisfaction in the job itself, human relationships, and working environment. The job satisfaction of the teachers in urban day care centers was influenced significantly by the related variables: age of teacher, marital status, education level, educational career, capacity, number of classes, class size, working hours, and the age of the children in class. The job satisfaction of the teachers in rural day care centers was influenced significantly by the above variables. The important factors on predicting the job satisfaction of the urban day care teachers were found to be the age of teachers, educational career, education level, and number of classes. The important factors for predicting the job satisfaction of the rural day care center teachers were found to be the age of teacher, educational career, education level, number of classes and working hours.

• Journal of the Korean Institute of Educational Facilities
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• v.13 no.1
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• pp.5-16
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• 2006

The study is intended to analyze the tendency of the remodeling for the middle schools in Gyeonggi Province, with the potential challenges thereof, thereby determining the principle for the remodeling projects in the days to come. To that end, the analysis to identify the school facilities in a bid to accommodate the current curriculum was conducted, along with the case study on remodeling projects. The $7^{th}$ curriculum demands for a significant change in school facilities. The number of student in a class that has been on the decline, despite of steady increase in number of schools, and the population getting concentrated in Seoul and its suburbs have resulted in an increase in number of class. Consequently, more investment in the facility, rather than improving a substantial education environment, has been made. The study, thus, is aimed at identifying the facility of the middle school required by the $7^{th}$ curriculum, as well as implementing a fact-finding investigation into the remodeling works for middle schools in Gyeonggi Province so as to come up with the guideline for remodeling projects.

• Journal of Korean Academy of Nursing
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• v.3 no.2
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• pp.53-65
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• 1973

In order to explore the present status of induced abortion, a survey was conducted on 578 married women : 320 employed women, 165 urban and 93 rural housewives, during the period form June, 1972 to september, 1972. The results were as follows: 1. The rates of induced abortion in urban housewives, employed women and rural housewives were 50.3%, 30.3% and 1l.8%, respectively. 2. With regard to the duration of marital life, the rate of induced abortion was higher group of 11-16 and 17-22 years of duration than those of less than 4 years ana more than 23 years. 3. There were significant differences between housewives and the employed women. and also between urban and rural housewives in the rates of induced abortion. 4. The mean number of pregnancies was 4.9 and 4.8 for the rural and urban housewives while for the employed women was 2.1. 5. The mean number of live births was 4.5 and 3.2 for the rural and urban housewives while for the employed women was 2.1. 6. Average number of living children of the women who had experienced induced abortions was 4.8 and 3.1 for the rural and urban housewives while for the employed . women was 2.5. 7. There was a significant correlation between induced abortions and social class or educational level. The higher their level of education or social class, the more frequently women were experienced induced abortions. 8. There was a significant correlation between experience of induced abortions and family planning practice, vis., the women who had experienced induced abortions made more use of family planning practices.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.12 no.1
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• pp.57-61
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• 1982

The author has made a study on the classification of the mandibular 3rd molars of Korean youths through dental radiography by means of Pell & Gregory's classification and on the prevalence of the dental caries of distal surface of the mandibular 2nd molar adjacent to the mandibular 3rd molars turned anteriorly. The results are as follow; 1. It was found that the largest case number was class I (272 cases, 52.9%) in the relation of the tooth to the ramus of the mandible and 2nd molar. 2. The mesio-angular position was the largest number (239 cases, 46.5%) in the relation of the long axis of the impacted mandibular 3rd molar to the long axis of the 2nd molar. 3. The mesio-angular position of class I was the largest number (140 cases, 27.2 %) in the relation of the tooth to the ramus of the mandible and 2nd molar and the long axis of the impacted mandibular 3rd molar to the long axis of the 2nd molar. 4. The average angle of the long axis of mandibular 3rd molar in mesioangular position or horizontal position to the occlusal plane was 143° 5. Mandibular 3rd molar with lesion such as dental caries or pericoronitis was 73 cases (14.2). 6. The caries incidence rate of the distal surface of the 2nd molar was about 3.1%.

• Journal of Digital Contents Society
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• v.8 no.2
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• pp.235-243
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• 2007

Students develop mathematical concepts through concrete operations in the area of mathematics. However, most of the learning contents provided on the web are not interactive and limit interactions with learners. To overcome the limitations, there have been needs to develop learning contents to support active interactions with students according to their cognitive levels. In this study, the curriculum of numbers and number operations in elementary mathematics was analyzed. Based on the object-oriented design principle, "Number Classes" on numbers and number operations were designed and implemented. A class-based learning applet was developed with theses "Number Classes". It was developed in small unit programs based on learning themes of mathematics in elementary schools. With this learning applet, the active explorations through easy operations will help students to learn concepts and principles of numbers and number operations. It will strengthen active interactions of students with computer.

• Journal of Korean Library and Information Science Society
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• v.18
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• pp.193-216
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• 1991

The purpose of this study is to analyze the area table of twenty editions of the DDC in order to identify what major changes have been made chronologically. The summaries about which were discussed according to the edition order about the change processes of the most extensive area table of the DDC auxiliary table are as follows. 1. It is from the 17th edition that area table appeared as a special auxiliary table in DDC for the first time and the method of classifying areas like from 930 to 999 which is regional history in history class was taken before the introduction of independent area table. 2. The entry numbers in which the area table was applied increased continuously until the 18th edition but the applied entry number was rather decreased in the 20th edition especially the number was mainly decreased in history class, this is the result of the fact that the entry was classified by area table without enumerating each regional history in history class except for the basic area since the 17th edition but recently at least the area of over national unit according to the necessity of enumerating the entry in regional history within history class. 3. The relocation or revision of area table was made according to the literary warrant of the relevant area by period political and administrative conditions and the request of related organization or classifiers of the area rather than by the topographical features therefore the revision was made chiefly about the highly interested Europe Northern America especially the United States. 4. The entry numbers which were expanded according to area indicate that gradual improvement for the international feature as the revision of edition is repeated is made but because of the expansion of Northern America, especially the United States, regional disproportion is represented by the occupation of 56% in the entire entry numbers of the United States in case of the 20th edition. Lastly, the reasonable reform plans of area table will have to be groped on the basis of the results of analysis above and the consideration about the problems in the development of area table of DDC and the other main classification systems.

• Journal of KIISE:Software and Applications
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• v.28 no.10
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• pp.785-794
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• 2001

Since there is no compatability between primitive types and class types in Java, values of primitive types cannot be assigned to variables of class types cannot be assigned to variables of primitive types. Primitive values must be converted to objects of wrapper classes and special methods must be called in order to extract the primitive values from those objects. In this paper we propose there methods which provide automatic transformation between primitive types and class types for their compatability. Those methods support compatability not only between primitive types but also between wapper classes. The first method utilizes the hierarchy of wrapper classes, the second utilizer java.lang.Number class, and the third utilizes the hierarchy of wrapper interfaces. Through comparison and performance measurement. we confirm that the third method works better than the others.