• Imaging Science in Dentistry
• /
• v.35 no.1
• /
• pp.33-40
• /
• 2005

Purpose : (1) To analyse the effect of exposure time, ROI size and one impact factor in the image processing procedure on estimates of fractal dimension; and (2) to analyse the correlated relationship between the fractal dimension and the Cu-Eq value (bone density). Materials and Methods : The cylindric bone phantoms of 6 large and 5 small diameter having different bone densities respectively and human dry mandible segment with copper step wedge were radiographed at 1.0 and 1.2 sec esposure (70 kVp, 7 mA) using one occlusal film and digitized. Eleven rectangular ROIs from 11 cylindric bone phantoms and 4 rectan-gular ROIs from cortical, middle, periodontal regions, and socket of bone were selected. Gaussian blurred Image was subtracted from original image of each ROI and multiplied respectively by 1, 0.8, and 0.5, and then the image was made binary, eroded and dilated once, and skeletonized. The fractal dimension was calculated by means of a box counting method in the software ImageJ. Results : The fractal dimension was decreased gradually with continued bone density decrease showing strong correlations (bone phantom; r> 0.87, bone; r> 0.68) under 70 kVp 1.0 sec M = 0.8. Fractal dimensions showed the significant differerence (p < 0.05) between two different exposure times on the same small ROI of bone phantom. Fractal dimensions between two different sizes of ROI on bone phantom showed the significant differerence (p < 0.05) under 1.2 sec exposure, but did not show it (p > 0.05) under 1.0 sec exposure. Conclusions : Exposure time, ROI size, and modifying factor during subtracting could become impacting on the results of fractal dimension. Fractal analysis with thoroughly evaluated method considering the various impacting factors on the results could be useful in assessing the bone density in dental radiography.

• Asian-Australasian Journal of Animal Sciences
• /
• v.30 no.8
• /
• pp.1066-1073
• /
• 2017

Objective: Growth-related traits are important economic traits in the swine industry. However, the genetic mechanism of growth-related traits is little known. The aim of this study was to screen the candidate genes and molecular markers associated with body dimension and body weight traits in pigs. Methods: A genome-wide association study (GWAS) on body dimension and body weight traits was performed in a White $Duroc{\times}Erhualian$ $F_2$ intercross by the illumina PorcineSNP60K Beadchip. A mixed linear model was used to assess the association between single nucleotide polymorphisms (SNPs) and the phenotypes. Results: In total, 611 and 79 SNPs were identified significantly associated with body dimension traits and body weight respectively. All SNPs but 62 were located into 23 genomic regions (quantitative trait loci, QTLs) on 14 autosomal and X chromosomes in Sus scrofa Build 10.2 assembly. Out of the 23 QTLs with the suggestive significance level ($5{\times}10^{-4}$), three QTLs exceeded the genome-wide significance threshold ($1.15{\times}10^{-6}$). Except the one on Sus scrofa chromosome (SSC) 7 which was reported previously all the QTLs are novel. In addition, we identified 5 promising candidate genes, including cell division cycle 7 for abdominal circumference, pleiomorphic adenoma gene 1 and neuropeptides B/W receptor 1 for both body weight and cannon bone circumference on SSC4, phosphoenolpyruvate carboxykinase 1, and bone morphogenetic protein 7 for hip circumference on SSC17. Conclusion: The results have not only demonstrated a number of potential genes/loci associated with the growth-related traits in pigs, but also laid a foundation for studying the genes' role and further identifying causative variants underlying these loci.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.38 no.3
• /
• pp.155-165
• /
• 1989

In this paper, design equations for the calculation of the dimensions and characteristics of the ferrite magnet DC motor are derived. Through the computer iterative calculation applying the parameter survey method with those equations, the design method is presented. The following facts and the propriety of the design method are identified by comparing with the computer simulation results and dimension elements for the proposed motor. (1) The dimension ratio and the pole arc ratio as simulation parameters are in close connection with the dimension elements and motor performance, and those values of the parameter are important factor in determining the reasonable dimension of the motor. (2) It is proved that the minimization of the ferrite magnet volume is possible by representing the permeance coefficient as a function of the flux density ratio only. (3) It is shown that the torque equation suggested by introducing the copper loss area density of the conductors located in the slot is available in the determination of motor dimensions.

• Journal of Forest and Environmental Science
• /
• v.36 no.2
• /
• pp.163-172
• /
• 2020

The objective of this study was to develop evaluation criteria for forest education using the Context, Input, Process, and Product (CIPP) model. To this end, we designed a survey based on expert advice and content analysis of previous studies on the CIPP model and forest education. The survey was conducted on 393 forest education specialists, and Cronbach's α coefficient was set as 0.6 or higher to verify reliability and validity, and to determine reliability by factor. Eventually, 52 out of 57 evaluation items were extracted, and the evaluation indexes were selected through factor analysis as follows: four evaluation indexes for the context dimension, namely "Clarity of goal setting," "Developing conditions for education," "Meeting of requirements," and "Institutional drive"; three evaluation indexes for the input dimension, namely "Acquisition of education infrastructure," "Establishment of operational support," and "Adequacy of assigned manpower"; four evaluation indexes for the process dimension, which were "Adequacy of budget allocation," "Expertise of forest education instructors," "Diversity of programs," and "Public-private academic partnership"; and five evaluation indexes for the product dimension, namely "Effectiveness of perception change," "Influence over the society," "Continuity of improvement in evaluation," "Continuity of education," and "Verification of the effects of education."

• Computers and Concrete
• /
• v.2 no.3
• /
• pp.239-248
• /
• 2005

The article presents the results of examination of the fractal dimension D of concrete specimen fracture surfaces obtained in fracture toughness tests. The concretes were made from three different types of coarse aggregate: gravel, dolomite and basalt aggregate. Ordinary concretes (C40) and high-performance concretes (HPC) were subjected to testing after 7, 14, 28 and 90 days of curing, respectively. In fracture toughness and compressive tests, different behaviours of concretes were found, depending on the type of aggregate and class of concrete (C40, HPC). A significant increase in the strength parameters tested occurred also after a period of 28 days (up to the $90^{th}$ day of curing) and was particularly large for concretes C40. Fractal examinations performed on fracture replicas showed that the fractal dimension D was diverse, depending on the coarse aggregate type and concrete class being, however, statistically constant after 7 and 14 days for respective concretes during curing. The fractal dimension D was the greater, the worse strength properties were possessed by the concrete. A cross-grain crack propagation occurred in that case, due to weak cohesion forces at the coarse aggregate/mortar interface. A similar effect was observed for C40 and HPC made from the same aggregate. A greater dimension D was exhibited by concretes C40, in which case the fracture was easier to form compared with high-performance concretes, where, as a result of high aggregate/mortar cohesion forces, the crack propagation was of inter-granular type, and the resulted fracture was flatter.

• The Journal of the Acoustical Society of Korea
• /
• v.36 no.2
• /
• pp.144-150
• /
• 2017

Musical genre is indispensible in constructing music information retrieval system, such as music search and classification. In general, the spectral characteristics of a music signal are obtained based on a subband decomposition to represent the relative distribution of the harmonic and the non-harmonic components. In this paper, we investigate the subband decomposition parameters in extracting features, which improves musical genre classification accuracy. In addition, the linear projection methods are studied to reduce the resulting feature dimension. Experiments on the widely used music datasets confirmed that the subband decomposition finer than the widely-adopted octave scale is conducive in improving genre-classification accuracy and showed that the feature-dimension reduction is effective reducing a classifier's computational complexity.

• Journal of Korean Academy of Nursing
• /
• v.18 no.2
• /
• pp.189-196
• /
• 1988

Health, a major concept in nursing, has not yet consistent or agreed upon definition. Although effective health care depends on clear communication between health care provider and client clear definition of health would enhance the promotion of quality in health care. There are no agreed definitions or criteria for overall health. An essentialstep would seem to be to determine commonly held meaning about the concept of health. Therefore, the study was aimed at identifying the Adult's perceptions of health concept. The subject's consisting of 312 adults, who were sampled through area sampling from May 10 to May 30,1988. The instruments used for this study were Health Conception Scale, which was developed by Smith, Laffrey's revised and tested its reliability. The data was Analyzed by S.P.S.S. program and the results were as follows ; 1. The results of the reliability test for content of health concept was $\alpha$＝.87. 2. The respondents perception of Health Meaning were inclined to emphasize the functional / role performance dimension rather than clinical dimension. 3. The perceptual level of health concept was proved to be significantly different by the variable : age, sex, religion, area marital status. In conclusion, adult's perception of Health Concept is revealed that functional and role performance dimension is more important than other dimensions. Futher study is necessary to clarify the structure of functional, adaptive, eudaimonistic dimension and systematic study with subculture will be and repetitive verification and modification of this tool is demanded.

• The Mathematical Education
• /
• v.55 no.4
• /
• pp.397-416
• /
• 2016

This study analyzed the quality of mathematics classes with observations using the instrument, MQI(Mathematical Quality of Instruction). Class recordings and interviews were conducted on 2 pre-service teachers and 4 in-service teachers. This study recorded and analyzed 3 or 4 classes for each mathematics teacher by using revised MQI. There were a total of 8 raters: 2 or 3 raters analyzed each class. MQI has four dimensions: Richness of the Mathematics, Working with Students and Mathematic, Errors and Imprecision, Student Participation in Meaning-Making and Reasoning. In the dimension of 'Richness of Mathematics', all teachers had good scores of 'explanations of teacher' but had lower scores of 'linking and connections', 'multiple procedures or solution methods' and 'developing mathematical generalizations.' In the dimension of 'Working with Students and Mathematics', two in-service teachers who have worked and having more experience had higher scores than others. In the dimension of 'Errors and Imprecision', all teachers had high scores. In the dimension of 'Student Participation in Meaning-Making and Reasoning', two pre-service teachers had contrast and also two in-service teachers who hadn't worked not long had contrast. Implications were deducted from finding to improving quality of mathematics classes.

• Journal of the Korean Society for Precision Engineering
• /
• v.15 no.6
• /
• pp.167-174
• /
• 1998

The ultrasonic test is recognized for its significance as a non-destructive testing method to detect volume defects such as porosity and incomplete penetration which reduce strength in the weld zone. This paper illustrates the defect detection in the weld zone of ferritic carbon steel using ultrasonic wave and the evaluation of pattern recognition by chaotic feature extraction using time series signal of detected defects as data. Shown in the time series data were that the time delay was 4 and the embedding dimension was 6 which indicate the geometric dimension of the subject system and the extent of information correlation. Based on fractal dimension and lyapunov exponent in quantitative chaotic feature extraction, feature value of 2.15, 0.47 is presented for porosity and 2.24, 0.51 for incomplete penetration The precision rate of the pattern recognition is enhanced with these values on the total waveform of defect signal in the weld zone. Therefore, we think that the ultrasonic pattern recognition method of weld zone defects of ferritic carbon steel by ultrasonic-chaotic feature extraction proposed in this paper can boost precision rate further than the existing method applying only partial waveform.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.40 no.4
• /
• pp.591-599
• /
• 2016

This study analyzes the somatotype of tall stature Korean women's lower body for proper slack patterns. The study subjects consist of 350 statures over 165cm in 18-59 aged women's of Size Korea 2010. Descriptive statistics, factor analysis, cluster analysis, ANOVA, Duncan test were used for analysis using SPSS 19.0. The result are as follows: Factor 1 was the horizontal dimension of waist and hip, factor 2 was the vertical dimension of lower body, factor 3 was the horizontal dimension of the lower limbs, factor 4 was the crotch length, and factor 5 was the horizontal dimension of hip. The lower body was divided into 3 types based on analysis of the above factors. Type 1 (46.6%) represented stout type with a thick and medium length of crotch and leg. Type 2 (22.7%) represented a curve type from waist to hip with long crotch length, while short and thin leg. Type 3 (30.7%) was referred as slender type, with short crotch length, while long and thin leg.