• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.9 no.2
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• pp.168-172
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• 1998

Several kinds of surgical methods have been used to treat the submucous cleft palate with hypernasality. The purpose of this study was to evaluate the double opposing Z-plasty which is one of the newly established surgical methods by Dr. Furlow in three cases of submucous cleft palate with hypernasality operated in this department. There were a number of advantage of double opposing Z-plasty. The surgery is adaptable for use in early patient. Midfacial growth retardation and complication were not seen in all cases. Hypernasality was improved subjectively. Using the nasometer, the nasalance score of the postoperative period was compared with that of before surgery, much improvement were noted in 'Ah', 'PaPa'. And fiberoptic endoscope was used to evaluate the velopharyngeal closure pattern. Velopharyngeal closure pattern with velum was improved dramatically, Double opposing Z-plasty seem to be a good procedure for the treatment of submucous cleft palate with hypernasality.

• Journal of the Korean Mathematical Society
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• v.48 no.3
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• pp.655-667
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• 2011

A class of functions involving divided differences of the psi and tri-gamma functions and originating from Kershaw's double inequality are proved to be completely monotonic. As applications of these results, the monotonicity and convexity of a function involving the ratio of two gamma functions and originating from the establishment of the best upper and lower bounds in Kershaw's double inequality are derived, two sharp double inequalities involving ratios of double factorials are recovered, the probability integral or error function is estimated, a double inequality for ratio of the volumes of the unit balls in $\mathbb{R}^{n-1}$ and $\mathbb{R}^n$ respectively is deduced, and a symmetrical upper and lower bounds for the gamma function in terms of the psi function is generalized.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.5
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• pp.637-653
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• 1999

In this study well-known burned rate expressions of Weibe function and double Wiebe function have been adopted for the combustion analysis of large two stroke marine diesel engine. A cycle simulation program was also developed to predict the performance and pressure waves in pipes using validated burned rate function,. Levenberg-Marquardt iteration method was applied to cali-brate the shape coefficients included in double Wiebe function for the performance prediction of two-stroke marine diesel engine. As a result the performance prediction using double Wiebe func-tion is well correlated withexperimental dta with the accuracy of 5% and pressure waves in intake and transport pipe are well predicted. From the results of this study it can be confirmed that the shape coefficients of burned rate function should be modified using the numerical method suggested for the accurated prediction and double Wiebe function is more suitable than Wiebe func-tion for combustion analysis of large two stroke marine engine.

• Transactions of Materials Processing
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• v.31 no.3
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• pp.143-150
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• 2022

The purpose of this study was to investigate an innovative hydroforming process for the cost-effective manufacturing of double layered tube with circumferentially corrugated patterns. Conventional double pipe heat exchanger has relatively poor heat transfer efficiency because of the limited contact area resulting from the concentrically arranged simple cylindrical structure. As a promising alternative to enhance heat transfer efficiency, double layered tube with corrugated internal pattern was considered in this study. To fabricate corrugated inner tube, innovative tube hydroforming system was developed. The customized loading paths were established using the simulated forming pressure and contracting stroke at various bar diameters. Experimentally obtained cross-sectional profiles were analyzed to evaluate the reliability and applicability of the hydroformed tube with various patterns. The results demonstrate that the proposed hydroforming process can be a feasible alternative for manufacturing high-performance double-tube heat exchangers.

• Computers and Concrete
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• v.9 no.1
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• pp.1-19
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• 2012

The size-effect study of various fracture parameters obtained from two parameter fracture model, effective crack model, double-K fracture model and double-G fracture model is presented in the paper. Fictitious crack model (FCM) for three-point bend test geometry for cracked concrete beam of laboratory size range 100-400 mm is developed and the different fracture parameters from size effect model, effective crack model, double-K fracture model and double-G fracture model are evaluated using the input data obtained from FCM. In addition, the fracture parameters of two parameter fracture model are obtained using the mathematical coefficients available in literature. From the study it is concluded that the fracture parameters obtained from various nonlinear fracture models including the double-K and double-G fracture models are influenced by the specimen size. These fracture parameters maintain some definite interrelationship depending upon the specimen size and relative size of initial notch length.

• Horticultural Science & Technology
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• v.30 no.1
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• pp.93-96
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• 2012

'Double Shine', a cultivar of Gypsophila paniculata was newly developed for the cut flowers by Jeollabuk-do Agricultural Research & Extension Services. It has morphological characteristics of the spreading plant type, double florets of many petals and two pistils, emarginate petal tip and cup shaped calyx. Also 'Double Shine' has several traits such as strong flower stalk, bright colored flower, narrow branching angle and more or less resistance to powdery mildew and pest injury. Furthermore, 'Double Shine' produced higher primary branches, and longer flower stalk length with internodal length and than did a check variety 'Bristol Fairy' during summer cultivation in subalpine areas. Blooming of 'Double Shine' was delayed by 16 days, its floret had broader width, compared to 'Bristol Fairy'. Moreover, 'Double Shine' produced normal flowers with two pistils and 8.5 stamens, with little production of malformed flowers in the high temperature condition.

• Geomechanics and Engineering
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• v.21 no.2
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• pp.123-132
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• 2020

Due to the various restrictions and problems related to the construction of new roads in urban areas, underground road construction has been receiving a great deal of attention in the field of tunnel engineering. In this study, a double-deck road tunnel with a diverging section was analyzed for the evaluation of its stability. Both numerical analysis and scale model tests were performed, the results were used to develop a stability evaluation method for double-deck tunnels with diverging sections constructed in rocks by NATM. From regression analyses conducted on the results of the numerical analysis, an equation and a chart were derived, these tools allow us to obtain the strength/stress ratio (SSR) for double-deck road tunnels with a diverging tunnel in various diverging conditions quickly and accurately. These tools have great potential to help engineers evaluate the stability of double-deck tunnels in the preliminary design stage.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.1
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• pp.73-82
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• 2004

Statment of problem : Little in known about the importance of selection of various double crowns as retainer in determining the outcome of treatment with double crown retained removable partial denture. Purpose : To obtain information about the effects and the results of this treatment modality. Material and methods : This study describes 61 double crown retained removable partial dentures worn by 51 patients from Samsung Medical Center, Seoul a time ranging between 6 and 48 months and evaluate occlusal contacts on the denture teeth, denture movement, incidence of denture relining, denture retention, fracture of dentures and abutments, hygiene, residual ridge inflammatory changes, number of lost abutment,. interruption of denture use. Results : One tenth of all the restorations were relined. Restorations in 21 arches fractured repeatedly for various reasons . There was no apparent interrelationship between fractures and the five groups. Conclusion : Good prognoses of removable partial dentures were shown in all groups(Kennedy Classes I, II, III, combination and few remaining abutment).

• Bulletin of the Korean Mathematical Society
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• v.59 no.1
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• pp.167-177
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• 2022

A vertex v of a graph G = (V, E) is said to ve-dominate every edge incident to v, as well as every edge adjacent to these incident edges. A set S ⊆ V is called a double vertex-edge dominating set if every edge of E is ve-dominated by at least two vertices of S. The minimum cardinality of a double vertex-edge dominating set of G is the double vertex-edge domination number γ_dve(G). In this paper, we provide an upper bound on the double vertex-edge domination number of trees in terms of the order n, the number of leaves and support vertices, and we characterize the trees attaining the upper bound. Finally, we design a polynomial time algorithm for computing the value of γ_dve(T) for any trees. This gives an answer of an open problem posed in [4].

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.245-250
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• 2005

Currently, many countries in the world operate double deck trains as one of the efficient, reliable and comfortable mass transportation systems. However, double deck trains have relatively big cross sectional areas that cause interface problems between the vehicles and infrastructures, and do not have enough spaces for installing electric equipments. Therefore, prior to the operation of double deck trains on the existing lines in Korea, careful investigations should be performed. In this study, we have designed the concept model of a double deck EMU train system and analyzed related problems.