• Journal of the Korean Data and Information Science Society
• /
• v.19 no.2
• /
• pp.413-420
• /
• 2008

This paper suggests a marginal logit mixed-effects for analyzing repeated binary response data. Since binary repeated measures are obtained over time from each subject, observations will have a certain covariance structure among them. As a plausible covariance structure, 1st order auto-regressive correlation structure is assumed for analyzing data. Generalized estimating equations(GEE) method is used for estimating fixed effects in the model.

• The Journal of Korean Academy of Prosthodontics
• /
• v.38 no.2
• /
• pp.214-225
• /
• 2000

The purpose of this study was to investigate the effects of investing conditions on the marginal discrepancy of conical telescope outer crown with Co-Cr-Ti alloy(Dentitan) and to compare the marginal discrepancy and the retention force of outer crowns using different pattern materials(plastic foil, casting wax, pattern resin). To evaluate the effects of investing conditions on the marginal discrepancy, patterns with plastic foil were invested under three different liquid/powder ratio conditions using phosphate bonded investment(Univest-nonprecious): standard, 10% decreased and 10% increased. At each liquid/powder ratio condition, metal ring was lined with single or double layers of ceramic ring liner. The marginal discrepancy of outer crown at different investing conditions was measured by ${\times}100$ compact measuring microscope(STM5, Olympus, Japan). For measurement of the marginal discrepancy and the retention force of outer crown using different pattern materials, the investing condition of 10% decreased liquid/powder ratio and double layers of ring liner was selected because this investing condition resulted in the best fit of outer crown. Marginal discrepancy was measured in the same way above and retention force on universal testing machine. Under the conditions of this study, the following conclusions were drawn: 1. The thickness of ring liner had more influence on the marginal discrepancy of outer crown than the liquid/powder ratio, and the acceptable marginal fitness could not be expected at the investing condition directed by investment manufacturer 2. There were no differences in the marginal discrepancy of outer crown among three different pattern materials(P>0.05). 3. Casting wax showed the greatest retention force(1640g) of outer crown, followed by pattern resin(1110g), plastic foil(820g). However, there was no significant difference between plastic foil and pattern resin(P>0.05). 4. Plastic foil showed the least variation in marginal discrepancy and retention force.

• Journal of the Korean Data and Information Science Society
• /
• v.19 no.2
• /
• pp.577-585
• /
• 2008

This paper suggests a marginal probability model for analyzing repeated polytomous response data when some factors are nested in others in treatment structures on a larger experimental unit. As a repeated measures factor, time is considered on a smaller experimental unit. So, two different experiment sizes are considered. Each size of experimental unit has its own design structure and treatment structure, and the marginal probability model can be constructed from the structures for each size of experimental unit. Weighted least squares(WLS) methods are used for estimating fixed effects in the suggested model.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.50 no.7
• /
• pp.333-339
• /
• 2001

The transmission networks are not perfect conductors and a percentage of the power generated is therefore lost before it reaches the loads. This network loss effects to the cost of suppling power to consumers, and must be considered if the most efficient dispatch and location of generators and loads is to be achieved. In this paper, we propose an approximate calculation of marginal loss factors to analyze characteristics of transmission loss of KEPCO power system. These static marginal loss factors are approximately calculated based on the KEPCO's expected summer peak load data of year 2000.

• The Korean Journal of Applied Statistics
• /
• v.14 no.1
• /
• pp.25-37
• /
• 2001

The marginal model is proposed for the analysis of data which have c(2: 3) categories in the 3 x 3 cross-over trials with three periods and three treatments. This model could be used for the counterpart of the Kenward-Jones' joint probability one and should be the generalization of Balagtas et ai's univariate marginal logits one, which analyze the treatment effects in the 3 x 3 cross-over trials with binary response variables[Kenward and Jones(1991), Balagtas et al(1995)]. The model equations for the marginal probability are constructed by the three types of link functions. The methods would be given for making of the link function matrices and model ones, and the estimation of parameters shall be discussed. The proposed model is applied to the analysis of Kenward and Jones' data.

• Journal of Nutrition and Health
• /
• v.22 no.2
• /
• pp.91-101
• /
• 1989

This study was performed to investigate the effects of different dietary magnesium levels on systolic blood pressure and mineral distribution in normotensive and spontaneously hypertensive rats. In experiment 1, Normotensive rats(NTR ; Sprague Dawley, Female) were given diets containing regular magnesium (0.05% Mg ; rMg), marginal magnesium (0.01% Mg ; mMg) or marginal magnesium with stress(0.01% Mg + stress ; mMg + Str). In experiment 2, spontaneously hypertensive rats (SHR ; Kyoto Wistar, Femal) were fed diets containing regular magnesium(0.05% Mg ; rMg) and high magnesium (0.2% Mg ; hMG). The following were found ; 1) NTR treated with marginal magnesium with stress showed significant increase in systolic blood pressure (SBP). Marginal magnesium diet without stress resulted in nonsignificant increase in SBP. Significant in crease of blood pressure showed in NTR treated with marginal magnesium and stress was associated with decreased magnesium and increased calcium content in femur, reticulocyte and plasma. 2) In experiment 2, magnesium supplementation to SHR showed significant attenuation of their systolic blood pressure with increasing age. The attenuation of SBP showed in SHR was associated with increased magnesium, lowered calcium content in cardiac muscle and reticulocyte and decreased plasma sodium and aldosterone level.

• Journal of Families and Better Life
• /
• v.19 no.6
• /
• pp.145-155
• /
• 2001

The purposes of this study were first to construct statistical and econometric models based on Amemiya\`s Type I Tobit mainly addressing the issue of statistical efficiency; second to explore income, price, and curvilinear age effects on the explained variable in order to illustrates its statistical marginal effects related to econometric issues; finally to provide invaluable insight for graphical simulations as a new interpretation approach using Tobit analysis. Results indicated that interpretation for the mean marginal effects of three possible cases of dependent variable was more likely to be evident to understand Tobit results compared to conventional analysis only using latent variable, beta. Results also revealed that prediction value of dependent variable can be possibly and easily projected by the independent variable changed whereas only beta value can not illustrate its projection as independent variables'changes.

• Restorative Dentistry and Endodontics
• /
• v.9 no.1
• /
• pp.69-79
• /
• 1983

This study was undertaken to evaluate the effects of varnish application and thermocycling on the marginal leakage. 240 cavities of Class V were prepared on the 120 extracted premolars, and the cavities were filled with amalgam, Heliosit$^{(R)}$, and Hipol$^{(R)}$ after application of Copalite$^{(R)}$ or Duraphat$^{(R)}$. All specimens were immersed in methylene blue solution for 24 hours after thermocycling at $4^{\circ}C$ and $60^{\circ}C$, embedded in acrylic resin, and sectioned with low speed saw into two parts. The sectioned specimens observed with the metallurgical microscope. The following results were obtained: 1. The marginal seal was more effective in the amalgam-filled cavities after application of Copalite$^{(R)}$ threetimes or an application of Duraphat$^{(R)}$ varnish than in those without varnish applications. 2. Of the composite resin-filled cavities, the leakage of the varnish applied cases showed much more than without application. 3. There was no significant difference in the effect of marginal sealing between Copalite$^{(R)}$ and Duraphat$^{(R)}$ applications. 4. There was a significant difference in the degree of the marginal leakage of amalgam-filled cavities between the groups of thermocycling times, but no significant difference in the resin-filled cavities. 5. There was no significant difference in the degree of the marginal leakage between the Heliosit$^{(R)}$ and the Hipol$^{(R)}$ resin-filled cavities.

• Restorative Dentistry and Endodontics
• /
• v.23 no.1
• /
• pp.296-303
• /
• 1998

The purpose of this study was to assess the effects of cavity designs on the marginal leakage of class 5 glass ionomer restorations. The five cavity designs were as follows ; notch shape(A group), notch shape with groove(B group), combined lesion(C group), combined lesion with groove and deep chamfer margin(D group) and combined lesion with groove and shoulder(E group), and each design had 10 cavities. After the cavities were restored with GIC, they were immersed in 0.5% basic fuchsin solution for 6 hours. The specimens were washed thoroughly and sectioned longitudinally in a buccolingual direction through the center of the restorations. The degree of marginal leakage was measured as the extent of dye penetration under the stereoscope. The results of this study were as follows 1. The enamel margins of all groups showed lesser leakage than dentin/cementum margins(p<0.05). 2. The combined lesion(C group) showed more leakage than notch shape(A group), but there was no siginificant difference(p>0.05). 3. In the notch shape, there was no influence on the marginal leakage by the groove preparation. 4. In the combined lesion, marginal leakage was decreased by the groove preparation and marginal modification.

• Journal of Periodontal and Implant Science
• /
• v.30 no.2
• /
• pp.455-472
• /
• 2000

Instrumentation for periodontal therapy may induce marginal damage which increases plaque accumulation and result in periodontal disease. But there have not been many reports of instrumentations on the artificial crown so far. Therefore this study is conducted to evaluate the effects of various repeated instrumentations on the porcelain crown marginal portion. Of the 10 extracted periodontally diseased maxillary first premolars, were 12 proximal surface used in this study. The finishing line of the preparation was placed on the root surface below CEJ and then the crown was cast and cemented in usual manner. Every 4 surfaces of the 3 instruments-curet, ultrasonic scaler, and ultrasonic curet- is used. and four samples used in each instruments. The relevant procedures and measurements were repeated 3 times in each surfaces. Marginal gap is measured by the microscope and surface roughness, Scannig Probe Microscope. Measurements are made at 5 points in each surfaces, making 20 points in each instrument. The results evaluated statistically were as follows 1. As instrumentation was repeated, both marginal gap and roughness were increased in all group 2. In the hand curet, marginal gap was increased every instrumentation and roughness was increased after second. 3. In the ultrasonic scaler, both marginal gap and roughness were increased every instrumentation. 4. In the ultrasonic curet, marginal gap was increased after third instrumentation and roughness was increased after second. 5. Marginal gap and roughness used by the ultrasonic curet were lower than the others and no difference was seen between the hand curet and ultrasonic scaler From the results of this study, the ultrasonic curet was useful in some aspect, but careful instrumentation was needed. Furthermore it was important to minimize the instrumentation through complete periodontal therapy before setting and adequate plaque control.