• The korean journal of orthodontics
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• v.34 no.4 s.105
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• pp.303-312
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• 2004

An unfavorable tipping movement can occur during the retraction of anterior teeth because orthodontic force is loaded by brackets positioned far from the center of resistance. To avoid this unfavorable movement, a compensating curved wire or lingual root torque wire is used. The purpose of this study is to investigate, using photoelastic material, the distribution of initial stress associated with the retraction of the incisors according to the degree of the compensating curve, to model changes associated with tooth ud alveolar bone structure. The following results were obtained by analysis of the polarizing plate of the effects of initial stress resulting from retraction of the anterior teeth: 1. When the incisors were retracted using combination archwire or sliding mechanics, the maximal polarizing pattern of the apical area decreased as the degree of the compensating owe increased from 0 to 15 to 30. 2. When the incisors were retracted by the combination archwire or sliding mechanics, the maximal polarizing pattern of the canine and premolar area increased as the degree of the compensating curve increased from 0to 15to 30. 3. A lower degree of polarizing patterns were associated with the combination archwire technique than the sliding mechanics technique at a given force. The above results indicate that there is no significant difference between the combination loop archwire technique and sliding mechanics, for the retraction of maxillary anterior teeth with decreased lingual tipping tendency by a compensating curve on the arch wire. However, the use of sliding mechanics is more effective for the prevention of lingual inclination of the anterior teeth, because the hook used in sliding mechanics is closer to the center of resistance of the maxillary anterior teeth.

• Journal of Soil and Groundwater Environment
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• v.18 no.7
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• pp.41-53
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• 2013

The study is to propose the optimal separation technique of heavy metals (Pb and Zn) contaminated in soil for improving the removal efficiency by various applicable techniques. The heavy metal contaminated soil samples near abandoned mine X-1 and X-2 were used for the study. Firstly, the wet classification process was shown more than 80% of removal efficiency for lead and zinc. Meanwhile, the magnetic separation process was shown low removal efficiency for lead and zincs because those heavy metals were non-magnetic materials. For the next step, the flotation separation process was shown approximately 24.4% of removal efficiency for zinc, while the gravity concentration process was shown approximately 57% of removal efficiency for lead, and 19.9% of removal efficiency for zinc, respectively. Therefore, zinc contaminated in soil would be effectively treated by the combination technique of the wet classification and the flotation technique. Meanwhile, lead contaminated in soil would be effectively treated by the combination technique of the wet classification process and the flotation process. Furthermore, the extraction of organic matter was shown more effective with aeration, 3% of hydrogen peroxide and 3% of lime such as calcium hydroxide.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.9 no.1
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• pp.89-101
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• 2014

Objectives : The purpose of this study is to report the effect of Korean medicine treatment combined with active release technique on supraspinatus tendon partial tear. Methods : Two patients with supraspinatus tendon partial tear were treated by Korean medicine treatment in combination with active release technique. Visual analog scale(VAS), range of motion(ROM) were used to measure changes during treatment. Results : After treatment, shoulder pain and limited range of motion were improved significantly. Conclusions : Korean medicine treatment in combination with active release technique is proved to be helpful to improve the symptoms of the supraspinatus tendon partial tear patients. And, further studies will be needed.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1140-1145
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• 2004

Laser-induced incandescence (LII) is introduced as a valuable tool for the characterization of nanoparticles in flame environments. This technique is based on the heating of the particles by a short laser pulse and the subsequent detection of the thermal radiation. It has been applied successfully for the investigation of soot in different fields of application. The evaluation of the temporal decay of the laser-induced incandescence (LII) signal from soot particles is introduced as a technique to obtain two-dimensional distributions of particle sizes and is applied to a laminar diffusion flame. This novel approach to soot sizing exhibits several theoretical and technical advantages compared with the established combination of elastic scattering and LII, especially as it yields absolute sizes of primary particles without requiring calibration. With this technique a spatially resolved 2-D measurement of soot primary particle sizes is feasible in a combination process form the ratio of emission signals obtained at two delay times after a laser pulse, as the cooling behavior is characteristic of particle size.

• PNF and Movement
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• v.16 no.3
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• pp.333-343
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• 2018

Purpose: The purpose of this study was to investigate the effects of a neck exercise using a proprioceptive neuromuscular facilitation (PNF) neck flexion and extension pattern on body balance in a progressive range of positions (supine, prone on elbow, and sitting), on numbness in the upper extremities, and on neck flexion motions in cervical myelopathy patients. Methods: One participant who was diagnosed with cervical myelopathy participated in this study. A reversal design (A-B-A') was used. The A and A' were the baseline period (no intervention), and B was the intervention period. The intervention used a neck extension pattern with a hold-relax technique and a neck flexion pattern with a combination of isotonic techniques in the supine position. Then, neck flexion and extension patterns were applied together with a reversal technique for stabilization, followed by a neck extension pattern with a combination of isotonic techniques in the prone position on the elbows. Finally, a neck flexion and extension pattern was used with a stabilizing reversal technique, and a neck extension pattern was applied with a combination of isotonic techniques in the sitting position for 60 minutes per day, 3 times per week for 8 weeks. To measure balance, numbness, and neck motion during neck flexion, the one-leg stand test and the visual analogue scale were used. Results: The right and left one-leg stand tests showed increased balance ability in the intervention phase. Upper extremity numbness was decreased in the intervention phase, and neck flexion motion was increased in the intervention phase. These increases were maintained after the intervention (Baseline II). Conclusion: These results suggest that a neck exercise using a PNF neck pattern with additional techniques in a progressive range of positions has a positive effect on cervical myelopathy patients for balance, numbness, and neck motion.

• The Korean Journal of Ecology
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• v.20 no.5
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• pp.303-313
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• 1997

A new evaluation technique, i.e. multicriterion matrix technique, on the vegetation assessment was proposed and compared with several techniques having been previously used in the environmental impact assessment. Four criterias and 10 subcriterias were selected for two evaluation indices such as vegetation naturalness value and vegetation class. These criterias were characterized by syntaxonomical informations of hemeroby concept and potential vegetation, hierarchical system between criterias, and ordinal scale of vegetation naturalness valuse. Vegetation naturalness values were classified into 11 ordinal levels and condensed to five vegetation classes for facilitating practical use. In the example study two sites were compared by using two indices. This technique could have useful applications for ssessment of regional vegetation. A vegetation map of naturalness described by combination of two indices was proposed in order to illustrate regional vegetation naturalness.

• Architectural research
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• v.11 no.2
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• pp.43-49
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• 2009

Since the late 1980s, the schedule technique applied to the construction industry around the world has rapidly changed from the traditional ADM (Arrow Diagramming Method) to the PDM (Precedence Diagramming Method) technique. The main reason for this change is to overcome the limits and inconveniences of the traditional ADM technique. The time-cost trade-off is one of the core scheduling techniques to establish the best optimized combination plan in terms of a relationship between the cost and schedule. However, most of the schedule-related textbooks and research papers have discussed and proposed applications of a time-cost trade-off technique based only on the Finish to Start relationship. Therefore, there are almost no consideration and discussion of problems or restrictions that emerge when the time-cost trade-off technique is applied to the PDM network that has overlapping relationships. This paper proposes the lead-time adjustment method as a methodology for overcoming some restrictions that are encountered when the time-cost trade-off technique is applied to the overlapping relationships of the PDM network.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.2 s.173
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• pp.526-534
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• 2000

Near-net-shape forming of zirconia powder was investigated under the combination of cold die and isostatic pressing and pressureless sintering. A novel combination pressing technique, i.e., die com paction under cold isostatic pressing, allowed to produce a complex shaped ceramic powder compact with the controlled dimensions and relatively uniform density distributions. The constitutive models proposed by Kim and co-workers for densification of ceramic powder under cold compaction and high temperature were implemented into a finite element program (ABAQUS). Experimental data for relative density distributions and deformations of zirconia powder compacts produced by cold combination pressing and pressureless sintering were compared with finite element results. Finite element results agreed well with experimental data.

• The Journal of the Korea Contents Association
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• v.20 no.12
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• pp.49-57
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• 2020

This study predicts the ratio of added value, which represents the competitiveness of export industries in South Korea, using various machine learning techniques. To enhance the accuracy and stability of prediction, forecast combination technique was applied to predicted values of machine learning techniques. In particular, this study improved the efficiency of the prediction process by selecting key variables out of many variables using recursive feature elimination method and applying them to machine learning techniques. As a result, it was found that the predicted value by the forecast combination method was closer to the actual value than the predicted values of the machine learning techniques. In addition, the forecast combination method showed stable prediction results unlike volatile predicted values by machine learning techniques.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.9
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• pp.1192-1196
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• 2004

In order to detect the molecular mechanism of heterosis in pigs, the mRNA differential display technique was performed to investigate the differences in gene expression of pig's Longissimus dorsi between the high-parent heterosis cross combination Landrace${\times}$Large White and the mid-parent heterosis cross combination Large White${\times}$Meishan. Three pig purebreds, Large White, Meishan, and Landrace and four types of reciprocal $F_1$ hybrids were analyzed using nine 3'-end anchored primers in combination with ten 5'-end arbitrary primers and nearly 7,000 reproducible bands were examined. The patterns of gene expression of each cross combination were analyzed and eight common patterns (fifteen kinds) were found. When the results from the two cross combinations were put together and compared, eight different typical expression patterns were observed, these indicated that the patterns of gene expression of these two cross combinations had obvious differences. Gene expression correlation and cluster analyses of the two cross combinations indicated that the gene expression of the mid-parent heterosis cross combination was correlated with maternal effect, but in the high-parent heterosis cross combination, paternal effect acted in the gene expression of the hybrids or the gene expression of the hybrids was biased towards one parent.