• Journal of Korean Elementary Science Education
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• v.29 no.4
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• pp.451-464
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• 2010

This study examined the perception of teachers and students on the practice of elementary science class. For this study, an examination tool was made by extracting characteristics of good science class through precedent study investigation and revising it in a questionnaire form of a Likert scale, and conducted to 194 elementary teachers and 320 elementary students. As a result of the study, teachers generally perceived science class positively and teachers with career more than 6 years thought it more positively than them with career less than 5 years. Consequently students have a substantially positive perception level about the practice of the elementary science class, and students of 3th and 4th grade perceived science class positively than 5th and 6th grade in all domains. Finally when analyzing perception difference between teachers and students about the practice of the elementary science class, it appeared that students perceived science class more positively than teachers in most questions.

• Journal of Chest Surgery
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• v.28 no.2
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• pp.143-149
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• 1995

From January, 1983, to August, 1993, 23 cases of pericardiectomy for chronic constrictive pericarditis were carried out. The 15 male and 8 female patients ranged in age from 7 to 68 years[mean 39.1 years . All patients underwent pericardiectomy through a median sternotomy. Postoperative complications were low cardiac output[2 patients , wound infection[2 patients , pneumonia[2 patients , and unilateral phrenic nerve palsy[2 patients . One patient died of low cardiac output 1 day after pericardiectomy due to the associated transposition of great artery and hypoplastic right lung. Clinical and pathological findings showed that the cause of constrictive pericarditis was tuberculous in 8 cases[34.8% , idiopathic in 12 cases[52.2% and pyogenic in 3 cases[13.0% . Central venous pressure fell below 10cmH2O by immediate in 6 cases, fell below 10cmH2O by 24hrs in 5 cases and continued above 10cmH2O after 24hrs in 12 cases. Preoperative NYHA functional class of patients showed class I-1, classII-4, class III-14, and class IV-3. Postoperativly NYHA functional class was improved to class I-15, classII-6, class III-1.

• The korean journal of orthodontics
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• v.20 no.3 s.32
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• pp.553-564
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• 1990

The purpose of this study was to compare mandibular teeth development of Angle Class I malocclusion group with that of Angle Class III malocclusion group. The studied subjects consisted of 217 Angle Class I malocclusion patients and 235 Angle Class III malocclusion patients. Two study methods were used. One was to evaluate tooth development degree by means of Nolla stage method, the others was to measure tooth length on panoramic radiograph. The following results were obtained, in 7, 8 and 9 years, tooth development of Angle Class III malocclusion group was significantly faster than that of Angle Class I malocclusion group. in 6 year and 10, 11, 12, 13, 14 years, the difference of tooth development degree between Angle Class III malocclusion group was not significant.

• Communications of the Korean Mathematical Society
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• v.12 no.4
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• pp.881-893
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• 1997

E. M. Silvia introduced the class $S^\lambda_\alpha$ of $\alpha$-spirallike functions f(z) satisfying the condition $$ (A) Re[(e^{i\lambda} - \alpha) \frac{zf'(z)}{f(z)} + \alpha \frac{(zf'(z))'}{f'(z)}] > 0, $$ where $\alpha \geq 0, $\mid$\lambda$\mid$ < \frac{\pi}{2}$ and $$\mid$z$\mid$ < 1$. We will generalize Silvia class of functions by formally replacing f(z) in the denominator of (A) by a spirallike function g(z). We denote the new class of functions by $Y(\alpha,\lambda)$. In this note we obtain some results for the class $Y(\alpha,\lambda)$ including integral representation formula, relations between our class $Y(\alpha,\lambda)$ and Ziegler class $Z_\lambda$, the radius of convexity problem, a few coefficient estimates and a covering theorem for the class $Y(\alpha,\lambda)$.

• Imaging Science in Dentistry
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• v.47 no.1
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• pp.1-9
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• 2017

Purpose: This retrospective study aimed to evaluate the nasopharyngeal and oropharyngeal dimensions of individuals with skeletal class II, division 1 and division 2 patterns during the pre-peak, peak, and post-peak growth periods for comparison with a skeletal class I control group. Materials and Methods: Totally 124 lateral cephalograms (47 for skeletal class I; 45 for skeletal class II, division 1; and 32 for skeletal class II, division 2) in pre-peak, peak, and post-peak growth periods were selected from the department archives. Thirteen landmarks, 4 angular and 4 linear measurements, and 4 proportional calculations were obtained. The ANOVA and Duncan test were applied to compare the differences among the study groups during the growth periods. Results: Statistically significant differences were found between the skeletal class II, division 2 group and other groups for the gonion-gnathion/sella-nasion angle. The sella-nasion-B-point angle was different among the groups, while the A-point-nasion-B-point angle was significantly different for all 3 groups. The nasopharyngeal airway space showed a statistically significant difference among the groups throughout the growth periods. The interaction among the growth periods and study groups was statistically significant regarding the upper oropharyngeal airway space measurement. The lower oropharyngeal airway space measurement showed a statistically significant difference among the groups, with the smallest dimension observed in the skeletal class II, division 2 group. Conclusion: The naso-oropharyngeal airway dimensions showed a statistically significant difference among the class II, division 1; class II, division 2; and class I groups during different growth periods.

• Proceedings of KOSOMES biannual meeting
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• 2005.11a
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• pp.53-58
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• 2005

An international study on Class B AIS for Non-SOLAS vessels is in progress through IMO and IEC. The IEC issued CDV(Committee Draft for Vote) on March 3, 2005, as IEC 62287, which includes operational and performance requirements, methods of test and required test results about Class B AIS. In this paper, we proposed the method of making Class B AIS properly onboard. This research deals with the problems of introducing Class B AIS which is properly applicable on small fishing vessels as well as domestic Non-SOLAS vessels. Moreover, several technical considerations were suggested to develop a national technical standards for Class B AIS.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.1
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• pp.90-96
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• 2011

In this paper, we propose a new discrete logarithm problem(DLP) based on the class semigroups of imaginary quadratic non-maximal orders using the special character of non-invertible ideal and analysis its security. To do this, we first explain the mathematical background explicitly and prove some properties of Cls (O) which relate to constructing the DLP and guaranteeing the security. To test the security of the proposed DLP, we compare the class number of the maximal order with that of the non-maximal order and investigate the unique factorization problems of ideals between class groups of the maximal orders and class semigroups of non-maximal orders to ensure the security of the cryptosystem.

• The korean journal of orthodontics
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• v.20 no.2
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• pp.333-354
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• 1990

This study was designed to analyse vertical dysplasia such as open bite or deep bite in persons with skeletal Class III malocclusion. The subjects consisted of 60 control patients, 40 Class III open bite patients and 40 Class III deep bite patients. The mean age was 19.8 years in the control group, 17.8 years in the Class III open bite group and 16.5 years in the Class III deep bite group. The results were as follows: 1. In Class III malocclusion patients, the characteristics of the vertical dysplasia are under the palatal plane. 2. In Class III malocclusion patients, the items showing the characteristics of the vertical dysplasia are mandibular plane angle, lower gonial angle, lower facial height, dental height & inclination of the upper first molar, interincisal angle, maxillary & mandibular occlusal plane angle. 3. In Class III malocclusion patients, LPFH/LAFH ratio shows the highest significance among the facial height ratios. 4. In Class III malocclusion patients, open bite group has a upward cant of maxillary occlusal plane & downward cant of mandibular occlusal plane. And deep bite group has a downward cant of maxillary occlusal plane & upward cant of mandibular occlusal plane. 5. In Class III malocclusion patients, the molar teeth of the open bite group are measially inclined and those of the deep bite group are upright.

• Journal of the Korean Society of Food Culture
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• v.26 no.3
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• pp.249-260
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• 2011

The current research aims to verify whether distance learning can be adopted in practical cooking class for Korean foods in a two-year college. The distance learning education can be a supplementary method to the traditional cooking class. The face-to-face teaching method and the distance learning method were compared in order to determine which of the one is more effective teaching method in the practical cooking class. The results of the present experimental study were analyzed based on the participant's learning expectation and satisfaction, the evaluation of the experimental process, and the academic performance. The results of this study showed that the participants in the face-to-face class evaluated their class experience higher than those in the distance learning class with respect to the participant's learning expectation and satisfaction, and the evaluation of the experimental process. On the contrary, regarding the academic performance, the participants in the distance learning class showed higher scores than those in the face-to-face class. The end result supports the claim that the distance learning method is more effective in the participants for gaining cooking knowledge.

• Journal of the Korean Home Economics Association
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• v.39 no.1
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• pp.169-178
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• 2001

In this study, we examined relationship among social class, conspicious consumption, dimensions of clothing price, and clothing buying behavior. The data were obtained by 290 female college students using questionnaire. The questionnaire were consist of four parts, dimensions of clothing price, conspicious consumption, clothing buying behavior, demographic factors. And the data were analysed with frequency, $x^2$-test, factor analysis, cluster analysis, ANOVA and Duncan test. The results were as follows. First, there was significant differences in social class and their attitude on dimensions of clothing price. Upper class consumers evaluate clothing price as Quality and dignity, on the other hand, lower class consumers perceived it as tendency for discount. Second, clothing selective standards was founded significantly different in social class. Clothing symbolic factor was more important to the upper class then lower class. Third, upper class consumers had a tendency of purchasing more clothes than lower class, and spend more money on clothing. Fourth, there was significant differences in conspicious consumption group and their attitude on dimensions of clothing price. Fifth, when conspicious consumption tendency is higher, importance of clothing price is highly perceived by college student. Sixth, Amount of clothing purchase and clothing expenditure were significantly different in conspicious consumption group. Consumers tend to buy more clothes and spend more money on clothes when they had high tendency in conspicious consumption.