• Title/Summary/Keyword: CUPID

Search Result 72, Processing Time 0.02 seconds

IMPROVEMENT OF A SEMI-IMPLICIT TWO-PHASE FLOW SOLVER ON UNSTRUCTURED MESHES (비정렬 격자계에서의 물-기체 2상 유동해석코드 수치 기법 개선)

  • Lee, H.D.;Jeong, J.J.;Cho, H.K.;Kwon, O.J.
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2010.05a
    • /
    • pp.380-388
    • /
    • 2010
  • A thermal-hydraulic code, named CUPID, has been developed for the analysis of transient two-phase flows in nuclear reactor components. A two-fluid three-field model was used for steam-water two-phase flows. To obtain numerical solutions, the finite volume method was applied over unstructured cell-centered meshes. In steam-water two-phase flows, a phase change, i.e., evaporation of condensation, results in a great change in the flow field because of substantial density difference between liquid and vapor phases. Thus, two-phase flows are very sensitive to the local pressure that determines the phase change. This in turn puts emphasis on the accurate evaluation of local pressure gradient. This paper presents a new numerical scheme to evaluate the pressure gradient at cell centers on unstructured meshes. The results of the new scheme for a simple test function a gravity-driven cavity, and a wall boiling two-phase flow are compared with those of the previous schemes in the cupid code.

  • PDF

Quadrilateral Flap Technique Applied for Complete Cleft Lip Patients - Report of cases - (완전구순열 환자에서 사각피판법의 적용 - 증례보고 -)

  • Nam, Il-Woo;Lee, Ju-Hwan;Lee, In-Woo;Seo, Byoung-Moo
    • Korean Journal of Cleft Lip And Palate
    • /
    • v.12 no.2
    • /
    • pp.65-72
    • /
    • 2009
  • Quadrilateral flap technique for primary cheiloplasty in patients with cleft lip was initially developed by Hagedorn in 1884. After Le Mesurier presented this procedure in 1940's, many surgeons adopted this technique for clinical advantage of reconstruction of Cupid's bow and lesser amount of tissue discarding than straight line technique. However, owing to its drawbacks such as sacrifice of Cupid's bow and prominent scar on philtral ridge, other techniques like Tennison's triangular flap and Millard's rotation-advancement flap have gradually taken its place. Nevertheless, some clinicians like Dr. Wang has modified this quadrilateral flap technique for better clinical outcomes. In this report we present 3 cases of unilateral complete cleft lip patients who underwent primary cheiloplasty with favorable outcomes based on Dr. Wang's modified quadrilateral flap technique.

  • PDF

Upper lip tie wrapping into the hard palate and anterior premaxilla causing alveolar hypoplasia

  • Heo, Woong;Ahn, Hee Chang
    • Archives of Craniofacial Surgery
    • /
    • v.19 no.1
    • /
    • pp.48-50
    • /
    • 2018
  • Bony anomaly caused by lip tie is not many reported yet. There was a case of upper lip tie wrapping into the anterior premaxilla. We represent a case of severe upper lip tie of limited lip motion, upper lips curling inside, and alveolar hypoplasia. Male patient was born on June 3, 2016. He had a deep philtral sulcus, low vermilion border and deep cupid's bow of upper lip due to tension of short, stout and very tight frenulum. His upper lip motion was severely restricted in particular lip eversion. There was anterior alveolar hypoplasia with deep sulcus in anterior maxilla. Resection of frenulum cord with Z-plasty was performed at anterior premaxilla and upper lip sulcus. Frenulum was tightly attached to gingiva through gum and into hard palate. Width of frenulum cord was about 1 cm, and length was about 3 cm. He gained upper lip contour including cupid's bow and normal vermilion border after the surgery. This case is severe upper lip tie showing the premaxillary hypoplasia, abnormal lip motion and contour for child. Although there is mild limitation of feeding with upper lip tie child, early detection and treatment are needed to correct bony growth.

Promotion of in vitro growth and rooting of micropropagated shoots in Spathiphyllum floribundum by the addition of liquid medium (액체배지 첨가에 의한 Spathiphyllum floribundum 신초의 기내생육 및 발근 촉진)

  • 한봉희;예봉우;구대회;신지수
    • Korean Journal of Plant Tissue Culture
    • /
    • v.28 no.4
    • /
    • pp.185-188
    • /
    • 2001
  • This experiments were carrid out to examine the effects of liquid medium addition in same vessels on shoot elongation and rooting, and soil survival of plantlets after the shoot cluster sections of Spathiphyllum floribundum 'Cupid' were pre-cultured. The shoot clusters with 3 to 4 small shoots were proliferated on LS medium supplemented with 2.0 mg/L BA for 8 weeks, and then 15 mL of various kinds of liquid medium was added in the same vessels. The addition of 15 mL liquid medium containing l/2 MS macro elements, 50 g/L sucrose and 5.0∼10.0 g/L activated charcoal was significantly stimulated the elongation and rooting of proliferated shoots. The medium addition was resulted in the enhanced soil survival of plantlets.

  • PDF

Assessment of CUPID code used for condensation heat transfer analysis under steam-air mixture conditions

  • Ji-Hwan Hwang;Jungjin Bang;Dong-Wook Jerng
    • Nuclear Engineering and Technology
    • /
    • v.55 no.4
    • /
    • pp.1400-1409
    • /
    • 2023
  • In this study, three condensation models of the CUPID code, i.e., the resolved boundary layer approach (RBLA), heat and mass transfer analogy (HMTA) model, and an empirical correlation, were tested and validated against the COPAIN and CAU tests. An improvement on HMTA model was also made to use well-known heat transfer correlations and to take geometrical effect into consideration. The RBLA was a best option for simulating the COPAIN test, having mean relative error (MRE) about 0.072, followed by the modified HMTA model (MRE about 0.18). On the other hand, benchmark against CAU test (under natural convection and occurred on a slender tube) indicated that the modified HMTA model had better accuracy (MRE about 0.149) than the RBLA (MRE about 0.314). The HMTA model with wall function and the empirical correlation underestimated significantly, having MRE about 0.787 and 0.55 respectively. When using the HMTA model, consideration of geometrical effect such as tube curvature was essential; ignoring such effect leads to significant underestimation. The HMTA and the empirical correlation required significantly less computational resources than the RBLA model. Considering that the HMTA model was reasonable accurate, it may be preferable for large-scale simulations of containment.

IMPLEMENTATION OF A SECOND-ORDER INTERPOLATION SCHEME FOR THE CONVECTIVE TERMS OF A SEMI-IMPLICIT TWO-PHASE FLOW ANALYSIS SOLVER (물-기체 2상 유동 해석을 위한 Semi-Implicit 방법의 대류항에 대한 이차정확도 확장)

  • Cho, H.K.;Lee, H.D.;Park, I.K.;Jeong, J.J.
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2009.04a
    • /
    • pp.290-297
    • /
    • 2009
  • A two-phase (gas and liquid) flow analysis solver, named CUPID, has been developed for a realistic simulation of transient two-phase flows in light water nuclear reactor components. In the CUPID solver, a two-fluid three-field model is adopted and the governing equations are solved on unstructured grids for flow analyses in complicated geometries. For the numerical solution scheme, the semi-implicit method of the RELAP5 code, which has been proved to be very stable and accurate for most practical applications of nuclear thermal hydraulics, was used with some modifications for an application to unstructured non-staggered grids. This paper is concerned with the effects of interpolation schemes on the simulation of two-phase flows. In order to stabilize a numerical solution and assure a high numerical accuracy, the second-order upwind scheme is implemented into the CUPID code in the present paper. Some numerical tests have been performed with the implemented scheme and the comparison results between the second-order and first-order upwind schemes are introduced in the present paper. The comparison results among the two interpolation schemes and either the exact solutions or the mesh convergence studies showed the reduced numerical diffusion with the second order scheme.

  • PDF

Repair of the Cleft Lip using Triangular Cheiloplasty-A Case Report (삼각피판법을 이용한 편측 불완전 구순열 환자의 구순 교정 수술-증례 보고)

  • Song, In-Seok;Hong, Jong-Rak;Choung, Pil-Hoon;Seo, Byoung-Moo
    • Korean Journal of Cleft Lip And Palate
    • /
    • v.10 no.2
    • /
    • pp.67-74
    • /
    • 2007
  • After Tennison introduced a triangular flap method which, for the first time, preserved the Cupid's bow, Randall gave this method a sound mathematical basis. This method is also called as an inferior triangular cheiloplasty which is characterized by making a small triangular flap from the lateral border of cleft destined to be fitted into an incision on the medial side of cleft. He postulated that the height obtained was equal to the sum of the median of the two triangles used in the cheiloplasty. Using this technique, a 22 month-old male patient with incomplete unilateral cleft lip was corrected primarily. The deviation of the columella and flattening of the nostril on the cleft side were minimal. The operation was done under general anesthesia and patient was healed uneventfully. We tried to improve the symmetry and esthetic feature of philtrum, nostril sill, alar-facial groove, preventing the notch formation on the nostril floor, and to reconstruct the muscle sling in the upper part of lip. The shape of Cupid's bow was restored, and the symmetry of columella was regained as a result. In summary, the inferior triangular cheiloplasty is effective to correct the primary unilateral cleft lip, results in the restoration of favorable anatomy and function.

  • PDF

A Case Study on Applying QFD to Improve Library Service Quality (도서관 서비스 품질 향상을 위한 QFD 적용에 관한 사례 연구)

  • Jung, Youngmi
    • Journal of Korean Library and Information Science Society
    • /
    • v.45 no.1
    • /
    • pp.319-338
    • /
    • 2014
  • This study aims to apply QFD model to improve and evaluate library service quality using user needs priorities. The library of the D University is presented as a case study. QFD is a powerful quality management method in which customer needs are translated into appropriate technical requirements for each stage of product/service development. To apply QFD in the field of library services, first library user needs and their AHP, satisfaction and importance degrees were examined via focus group interview. Second, the service improvement engineering characteristics for satisfying the user needs and their relationship/correlations matrices were defined by interviewing library practitioners and experts. Finally, the data collected was entered using CUPID solution, and then HOQ to improve library service quality of the D University was constructed. This study focused on QFD method and its application as a tool for improving the quality of library service.

Modified Fisher method for unilateral cleft lip-report of cases

  • Kim, Hui Young;Park, Joonhyoung;Chang, Ming-Chih;Song, In Seok;Seo, Byoung Moo
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.39
    • /
    • pp.12.1-12.5
    • /
    • 2017
  • Background: Rehabilitation of normal function and form is essential in cleft lip repair. In 2005, Dr. David M. Fisher introduced an innovative method, named "an anatomical subunit approximation technique" in unilateral cleft lip repair. According to this method, circumferential incision along the columella on cleft side of the medial flap is continued to the planned top of the Cupid's bow in straight manner, which runs parallel to the unaffected philtral ridge. Usually, small inlet incision is needed to lengthen the medial flap. On lateral flap, small triangle just above the cutaneous roll is used to prevent unesthetic shortening of upper lip. This allows better continuity of the Cupid's bow and ideal distribution of tension. Case presentation: As a modification to original method, orbicularis oris muscle overlapping suture is applied to make the elevated philtral ridge. Concomitant primary rhinoplasty also results in good esthetic outcome with symmetric nostrils and correction of alar web. As satisfactory results were obtained in three incomplete and one complete unilateral cleft lip patients, indicating Fisher's method can be useful in cleft lip surgery with functional and esthetic outcome. Conclusions: Clinically applied Fisher's method in unilateral cleft lip patients proved the effectiveness in improving the esthetic results with good symmetry. This method also applied with primary rhinoplasty.

Investigation of subcooled boiling wall closures at high pressure using a two-phase CFD code

  • Alatrash, Yazan;Cho, Yun Je;Song, Chul-Hwa;Yoon, Han Young
    • Nuclear Engineering and Technology
    • /
    • v.54 no.6
    • /
    • pp.2276-2296
    • /
    • 2022
  • This study validates the applicability of the CUPID code for simulating subcooled wall boiling under high-pressure conditions against number of DEBORA tests. In addition, a new numerical technique in which the interfacial momentum non-drag forces are calculated at the cell faces rather than the center is presented. This method reduced the numerical instability often triggered by calculating these terms at the cell center. Simulation results showed good agreement against the experimental data except for the bubble sizes in the bulk. Thus, a new model to calculate the Sauter mean diameter is proposed. Next, the effect of the relationship between the bubble departure diameter (Ddep) and the nucleation site density (N) on the performance of the Wall Heat Flux Partitioning (WHFP) model is investigated. Three correlations for Ddep and two for N are grouped into six combinations. Results by the different combinations show that despite the significant difference in the calculated Ddep, most combinations reasonably predict vapor distribution and liquid temperature. Analysis of the axial propagations of wall boiling parameters shows that the N term stabilizes the inconsistences in Ddep values by following a behavior reflective of Ddep to keep the total energy balance. Moreover, ratio of the heat flux components vary widely along the flow depending on the combinations. These results suggest that separate validation of Ddep correlations may be insufficient since its performance relies on the accompanying N correlations.