• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.3
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• pp.613-623
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• 2011

In this paper, we present a method on the construction of quinternary logic circuits using Perfect shuffle. First, we discussed the input-output interconnection of quinternary logic function using Perfect Shuffle techniques and Kronecker product, and designed the basic cells of performing the transform matrix and the reverse transform matrix of quinternary Reed-Muller expansions(QRME) using addition circuit and multiplication circuit of GF(5). Using these basic cells and the input-output interconnection technique based on Perfect Shuffle and Kronecker product, we implemented the quinternary logic circuit based on QRME. The proposed design method of QRME is simple and very efficient to reduce addition circuits and multiplication circuits as compared with other methods for same logic function because of using matrix transform based on modular structures. The proposed design method of quinternary logic circuits is simple and regular for wire routing and possess the properties of concurrency and modularity of array.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.2
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• pp.104-111
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• 2015

Purpose: The aim of this retrospective study was to investigate the prevalence rate and types of C-shaped roots and C-shaped canal in maxillary molars by analyzing cone-beam computed tomography (CBCT) in a Korean population. Materials and Methods: Total of 357 CBCT images of maxillary molars (186 first molar, 171 second molar) were evaluated by two Endodontic specialists. Results: Eight types of C-shaped roots and 5 types of C-shaped canals were founded, the prevalence rate of C-shaped roots and canals were 21.0% and 5.3% respectively. Conclusion: These anatomical variations were more frequent in second molars than the first molars. Clinicians should have anatomical knowledge about various types of C-shaped root and root canal for successful root canal therapy.

• Journal of the Korean Data and Information Science Society
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• v.23 no.4
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• pp.657-663
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• 2012

There are very small values and/or very big values which get out of the normal range for survey data in various fields. The reasons of occurrence for outlier are two. One of them is the error in process of data input and the other is the strange response of the respondent. If the data has outliers, then the summary statistics such as the mean and the variance produce misleading information. Therefore, researcher should be careful in detecting the outlier in data. In particular, it is very important problem for clinical fields because the cost of experiment is very high. This article introduce the Grubb test and Cochran test to detect outliers in the data and we apply this method for clinical data.

• Journal of Korean Society of Transportation
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• v.22 no.6
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• pp.67-77
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• 2004

A treatment of outlier has been discussed. Outliers disrupt the reliability of information systems and they should be eliminated prior to the information and/or data fusion. A time series-based elimination algorithm were proposed and prediction interval, as a criterion of acceptable value width, was obtained with the model. Ten actual link values were used and the best model was identified as IMA(1,1). Although the actual verification was difficult in a sense that the matching process between the eliminated data and model data was not readily available, the proposed model can be successfully used in practice with some calibration efforts.

• Journal of Korean society of Dental Hygiene
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• v.18 no.6
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• pp.1013-1023
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• 2018

Objectives: The purpose of this study is to evaluate dental hygiene students' recognition of safety management and phantom practice in dental radiology. Methods: The study subjects were 409 students in six regions who completed a dental radiology practice course and had on-job experience more than once. After understanding the study purpose and contents, they answered a questionnaire. The main jobs in dental radiology were analyzed. Results: As a result, regarding the most difficult aspects of dental radiology practice, "it is impossible to irradiate the mouth directly with X-rays" was the most common response (29.1%). Regarding the question "what is the main role of students in dental radiology practice?", the answer "it is shooting simulations using phantoms" accounted for 59.7% of responses. The most difficult regions in bisecting and paralleling radiography with a phantom were found to be the maxillary & mandibular molars and premolars. The most difficult technique was reported to be locating XCP maintenance to fit inside the mouth for both molars and premolars. The most difficult region to perform bitewing radiography using the phantom was the molar region (2.87), and the most difficult to perform occlusal radiography approaches were maxillary anterior general occlusal radiography (2.92) and mandibular cross-sectional occlusal radiography (3.00). Conclusions: The most technically difficult point in bitewing and occlusal radiography was the correct positioning of the vertical and horizontal angles. Radiography practice was considered to be more effective than previous mutual practice in terms of analysis of anatomical structures and patient treatment methods. Therefore, it will be necessary to improve policy regarding dental radiography practice at the department of dental hygienics and revise the necessary laws and regulations.

• Journal of the korean academy of Pediatric Dentistry
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• v.49 no.3
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• pp.348-356
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• 2022

Supernumerary teeth develop from excessive proliferation and development of the dental lamina. Supernumerary teeth can cause several problems, including ectopic eruption, delayed eruption, root resorption of adjacent teeth, and diastema. Supernumerary teeth in infancy are rare and have rarely been reported. Case of a 2-day-old infant with 3 supernumerary teeth is presented here and the patient was followed up for 21 months. The erupted supernumerary tooth in the primary dentition was extracted under moderate sedation at the age of 14 months. Microcomputed tomography analysis of the extracted tooth confirmed microscopic root malformation. After extraction, the midline diastema was reduced and oral hygiene improved. Early diagnosis and prompt treatment can prevent complications of supernumerary teeth.

• Journal of Korean society of Dental Hygiene
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• v.24 no.2
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• pp.99-108
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• 2024

Objectives: This study aimed to verify the effect on students' competency and self-directed capacity after a capstone design teaching method with community dental hygiene class. Methods: The study participants were 34 dental hygiene students taking a 4-year community dental hygiene course at a university located in City C. The research tool consisted of 52 questions on major competency and 20 questions on self-directed capacity. Results: After the capstone design class, overall dental hygienists' competency increased (p<0.05), and competencies of clinical dental hygiene and community health promotion showed a high increase (p<0.001). As a result of analyzing the increase in dental hygienists' competency according to self-directed learning ability, the group with low self-directed capacity showed high improvement in clinical dental hygiene competency and community oral health promotion competency. Conclusions: This study confirmed that the capstone design course in community dental hygiene improved students' competency and self-directed capacity, and suggests that it is an excellent teaching method for training competencies required for future society.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.2
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• pp.187-191
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• 2016

Early loss of a primary second molar can cause mesial drift or tilting of the permanent first molar. We present a case of the early loss of the mandibular primary molars in a 5-year-old girl. The patient required extraction of the mandibular left primary first and second molars due to folliculitis on the successors. A flexible denture was used for eruption guidance of the permanent first molar and the recovery of masticatory function simultaneously.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.4
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• pp.454-462
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• 2020

Proper treatment of an impacted tooth is required as it causes functional and esthetic disharmony, as well as it can cause root absorption of adjacent teeth. Treatment options for impacted teeth include periodic observation, surgical exposure, orthodontic traction followed by surgical exposure, tooth transplantation, and extraction. Modified Nance appliance, used for orthodontic traction, is clinically useful because it does not require patient cooperation. Through orthodontic traction combined with surgical exposure of impacted maxillary incisors, canines, and molars using modified Nance appliance, adequate results can be obtained.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.1
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• pp.76-82
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• 2002

This paper presents a quaternary-binary decoder, a quaternary logic current buffer, and a quaternary logic full-adder using current-mode multiple-valued logic CMOS circuits. Proposed full-adder requires only 15 MOSFET, 60.5% and 48.3% decrease of devices are achieved compared with conventional binary CMOS full-adder and Current's full-adder. Therefore, decrease of area and internal nods are achieved. Designed circuits are simulated and verified by HSPICE. Proposed full-adder has 1.5 ns of propagation delay and 0.42㎽ of power consumption. Also, proposed full-adder can easily adapted to binary system by use of encoder, designed decoder and designed current buffer.