• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2003.05a
• /
• pp.44-48
• /
• 2003

In metal working, cold forging that has profit to satisfy dimension accuracy is using in various manufacturing products. Recently, most of the interest thing is precision forging of gear, Gear forging product is more strength than broaching gear, and it has many advantages with reduction of factory expenses. The reason of difficulty to improve accuracy of gear dimension compare to another products is the dimension accuracy is very high, approximately 10$\mu\textrm{m}$, and because die of involute teeth and elastic strain of forged tool differ from standard curve. This paper represent quantitative analysis of die and teeth of forged tool, namely difference of curves, with experiments and analyze the factor of dimension gap, finally, will design compensated involute curve.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• v.12 no.1
• /
• pp.1-5
• /
• 2012

Data reduction has been used widely in data mining for convenient analysis. Principal component analysis (PCA) and factor analysis (FA) methods are popular techniques. The PCA and FA reduce the number of variables to avoid the curse of dimensionality. The curse of dimensionality is to increase the computing time exponentially in proportion to the number of variables. So, many methods have been published for dimension reduction. Also, data augmentation is another approach to analyze data efficiently. Support vector machine (SVM) algorithm is a representative technique for dimension augmentation. The SVM maps original data to a feature space with high dimension to get the optimal decision plane. Both data reduction and augmentation have been used to solve diverse problems in data analysis. In this paper, we compare the strengths and weaknesses of dimension reduction and augmentation for classification and propose a classification method using data reduction for classification. We will carry out experiments for comparative studies to verify the performance of this research.

• Journal of Korea Multimedia Society
• /
• v.20 no.9
• /
• pp.1567-1573
• /
• 2017

The k-nearest neighbor (k-NN) algorithm is one of the most widely used benchmark algorithm in classification. Nowadays it has been further applied to predict time series. However, one of the main concerns of the algorithm applied on short-term electricity load forecasting is high computational burden. In the paper, we propose an approach of dimension reduction that follows the principles of highlighting the temperature effect on electricity load data series. The results show the proposed approach is able to reduce the dimension of the data around 30%. Moreover, with temperature effect highlighting, the approach will contribute to finding similar days accurately, and then raise forecasting accuracy slightly.

• Journal of the Korean Home Economics Association
• /
• v.34 no.3
• /
• pp.137-155
• /
• 1996

The purpose of this study was to identify the relative influence of OCM and BSM's family functioning dimensions and develop a new family system model related to adolescent adjustment. The 443 subjects were selected randomly from the second grade of middle and high schools in the city of Taegu. The survey instruments were FACESⅢ, SFI-Ⅱ, State-Trait Anxiety Inventory, Depression Scale, Self-Esteem Scale, and Delinquency Scale, Factor Analysis, Cronbach's α, Multiple Regression, MANOVA, Scheffe test were conducted for the data analysis. The major findings of this study were as follows: First, OCM's and BSM's family functioning dimensions respectively had different relative influence that affected adolescent adjustment level. In anxiety and depression. BSM's family health/competence dimension had superior influence to any other family functioning dimensions and in self-esteem and delinquency, OCM's cohesion dimension was superior to any other family functions. Second, family system classification method by a new family system model using family cohesion(OCM's relationship dimension) and family health/competence(BSM's change dimension) was more useful than OCM in evaluating adolescent adjustment.

• Journal of the Korean Society of Safety
• /
• v.17 no.4
• /
• pp.38-44
• /
• 2002

The application of fractal concept provides an useful method in the study for the quantitative analysis of irregular variations like the fracture surfaces and crack profiles. Fractal curves have characteristics that represents a self-similarity based on the fractal dimension. The fractal dimensions were obtained by the box counting method. In this report, we obtained the nearly stable fractal dimensions of fracture crack profiles for STS316 with CT specimen as the crack advances and the relationships between crack length and fractal dimension. Moreover fractal fracture parameter that corresponds to J-R curve is shown by the relationships between fractal dimension and crack extension. From the results, we concluded that crack extension of high toughness material also shows the fractal characteristics, which can be used in order to evaluate the crack life precisely.

• Journal of information and communication convergence engineering
• /
• v.1 no.1
• /
• pp.53-57
• /
• 2003

Chaos theory is a study researching the irregular, unpredictable behavior of deterministic and non-linear dynamical system. The interpretation using Chaos makes us evaluate characteristic existing in status space of system by tine series, so that the extraction of Chaos characteristic understanding and those characteristics enables us to do high precision interpretation. Therefore, This paper propose the new method which is adopted in extracting character features and recognizing characters using the Chaos Theory. Firstly, it gets features of mesh feature, projection feature and cross distance feature from input character images. And their feature is converted into time series data. Then using the modified Henon system suggested in this paper, it gets last features of character image after calculating Box-counting dimension, Natural Measure, information bit and information dimension which are meant fractal dimension. Finally, character recognition is performed by statistically finding out the each information bit showing the minimum difference against the normalized pattern database. An experimental result shows 99% character classification rates for 2,350 Korean characters (Hangul) using proposed method in this paper.

• International Journal of Computer Science & Network Security
• /
• v.22 no.11
• /
• pp.338-347
• /
• 2022

The current study aimed to identify the reality of the transitional services provided to people with intellectual disabilities from the parent's point of view. The results indicated an average level, with an arithmetic mean (3.66) of the reality of transitional services provided to students with intellectual disabilities through the response of the study participants to the questionnaire consisting of (20) items. The dimension (social and societal skills) ranked first with an arithmetic average (4.03) with a high degree, through the response of the participants in the study to the items of the dimension consisting of (10) items. It was followed by the dimension (self-determination skills) with an arithmetic average of (3.29) to a medium degree, through the response of the participants in the study to the items of the dimension consisting of (10) items. The researchers recommend the necessity of joint planning by all relevant authorities, to solve the legal, societal, technical, and administrative problems and challenges that impede the provision of transitional services for students with intellectual disabilities.

• Korean Journal of Community Nutrition
• /
• v.17 no.3
• /
• pp.321-328
• /
• 2012

The purpose of this study is to investigate how certain factors influence job satisfaction and turnover intention of the dietitians working at the correctional institutions. A total 47 sheets of questionnaires (complete enumeration) were distributed respectively to the dietitians during the period from March 20th to May 18th of 2008. A total of 38 questionnaires (response rate 81%) were analyzed by using SPSS (ver. 19.0). The dietitians were more satisfied with coworkers ($3.63{\pm}0.10$) and supervision ($3.19{\pm}0.13$) than with pay ($2.97{\pm}0.09$) and promotion ($2.55{\pm}0.08$). Among the job burnout dimensions, cynicism ($2.58{\pm}0.09$) was rated higher than exhaustion ($2.47{\pm}0.10$), while professional efficacy level ($3.40{\pm}0.08$) was relatively high. The work dimension of job satisfaction was negatively correlated with exhaustion and cynicism dimensions of job burnout (p < 0.001), and turnover intention (p < 0.01), but positively correlated with professional efficacy dimension (p < 0.001). The co-worker dimension was negatively correlated with exhaustion and cynicism (p < 0.05) and turnover intention (p < 0.01), while the supervision, the pay, and the promotion dimension were not correlated with the job burnout and turnover intention. The turnover intention was positively correlated with exhaustion and cynicism dimensions of job burnout (p < 0.001). A stepwise regression analysis revealed that i) professional efficacy was a factor to significantly increase the work dimension of job satisfaction, ii) exhaustion and cynicism to significantly decrease the work and the co-worker dimension of job satisfaction, respectively, and iii) exhaustion to significantly increase turnover intention. The managerial efforts of the institutions could be focused on the job burnout factors to effectively increase the work dimension and the co-worker dimension of the job satisfaction.

• Korean Journal of Community Nutrition
• /
• v.14 no.2
• /
• pp.182-189
• /
• 2009

The purpose of this study is to investigate how certain factors-especially dietitians' general characteristics and job burnout-influence their job satisfaction and turnover intention. The survey was conducted during the period from September 7th to October 15th of 2006. A total of 91 institutions(response rate 74.6%) was analyzed by using SPSS(windows ver. 14.0). A majority of the respondents were females(97.8%) and 30 years or older(66.0%). Among the job burnout dimensions, exhaustion($2.78{\pm}0.07$) was rated higher than cynicism($2.62{\pm}0.06$), while the professional efficacy level($3.55{\pm}0.05$) was relatively high. The dietitians were more satisfied with co-workers($3.73{\pm}0.07$) and work($3.41{\pm}0.06$) than with pay($2.66{\pm}0.07$) and promotion($2.32{\pm}0.07$). The work dimension of job satisfaction was negatively correlated with exhaustion and cynicism dimensions of job burnout, and turnover intention(p<0.001), but positively correlated with professional efficacy dimension(p<0.001). The supervision dimension was negatively correlated with cynicism(p<0.05) and turnover intention(p<0.001), but positively correlated with professional efficacy dimension(p<0.01). The co-workers dimension was positively correlated with professional efficacy dimension(p<0.01). The pay dimension was negatively correlated with exhaustion(p<0.001) and cynicism(p<0.01) dimensions and turnover intention(p<0.001). The promotion dimension was negatively correlated with cynicism(p<0.01). The turnover intention was positively correlated with exhaustion and cynicism dimensions of job burnout(p<0.001). A hierarchical regression analysis revealed that i) professional efficacy was a factor to significantly increase job satisfaction, ii) cynicism to significantly decrease their job satisfaction, and iii) exhaustion to significantly increase turnover intention.

• Journal of the Korean Wood Science and Technology
• /
• v.15 no.2
• /
• pp.53-66
• /
• 1987

Korean red pine (Pinus densiflora S. et. Z.) and pitch pine(Pinus rigida Mill) $5{\times}10cm$ dimension lumber were dried in a kiln providing a cross-circulation velocity of 5 m/sec at dry-and wet-bulb temperatures of 116 and $71^{\circ}C$, followed by 3 hours at 91 and $85^{\circ}C$. Compared to dimension lumber dried lumber were as follows. 1. To dry to 10 percent moisture content, the high-temperatures schedule of Korean red pine and pitch pine lumber took less than one seventh the time required by the conventional kiln drying schedule. 2. High-temperature drying rate and conventional drying rate to 10 percent moisture content of Korean red pine lumber were 2.75 and 0.35%/hr, and those of pitch pine lumber were 3.38 and 0.46%/hr respectively. 3. Compared to lumber of both species on conventional schedule, moisture gradient of high-temperature lumber was greater. 4. Compared to lumber on conventional schedule, maximum surface checking of high-temperature lumber of both species was severer, and maximum end checking of high-temperature lumber of both species was similar to that of lumber on conventional schedule. 5. Compard to lumber on conventional schedule, Korean red pine lumber dried at high temperature showed more honeycombing, but pitch pine lumber dried at high-temperature showed significantly slighter honeycombing. 6. Compared to lumber on conventional schedule, the high-temperature lumber showed less warping lumber of both species. 7. Collapse and casehardening of Korean red pine and pitch pine lumber on both scheules were slight.