• Title/Summary/Keyword: cavity volume

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A STUDY OF THE CORRELATIONS BETWEEN THE TONGUE AND ORAL CAVITY VOLUME IN THE SKELETAL MANDIBULAR PROGNATHISM (골격성 하악전돌자의 혀와 구강용적의 상관관계에 대한 연구)

  • Choi, Yang-Sook;Son, Woo-Sung
    • The korean journal of orthodontics
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    • v.23 no.2 s.41
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    • pp.275-282
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    • 1993
  • When mandibular prognathic patients are operated orthognathic surgery which reduce the oral cavity volume, tongue volume should be harmonized with oral cavity volume to be changed because prevent the relapse of malocclusion. To decide the need for tongue resection, the author measured the tongue volume and oral cavity volume with stone model which were taken by impression method and study the difference between the ratio of tongue and oral cavity volume in mandibular prognathic group and normal group. The samples were consisted of four groups, the 40 subjects of the control group, 40 subjects of the experimental group. Each group was subdivided into male and female group respectively. The results were as follows : 1. The tongue volume and oral cavity volume measurements are $20.7cm^3,\;32.7cm^3$ in the control group respectively, and $24.9cm^3,\;42.9cm^3$ in the experimental group respectively. 2. There is no difference in the ratio of the tongue volume to oral cavity volume in control group and experimental group. 3. Correlation coefficients between the tongue volume and oral cavity volume are 0.11, 0.29 in experimental group and control group respectively, and 0.43 in gross total group. 4. The tongue volume of male is larger than female(p<0.05).

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Volumetric changes in the lumpectomy cavity during whole breast irradiation after breast conserving surgery

  • Cho, Heung-Lae;Kim, Cheol-Jin
    • Radiation Oncology Journal
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    • v.29 no.4
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    • pp.277-282
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    • 2011
  • Purpose: This study was performed to evaluate the change in the lumpectomy cavity volumes before and after whole breast radiation therapy (WBRT) and to identify factors associated with the change of volume. Materials and Methods: From September 2009 to April 2010, the computed tomography (CT) simulation data from 70 patients obtained before and after WBRT was evaluated. The lumpectomy cavity volumes were contoured based on surgical clips, seroma, and postoperative changes. Significant differences in the data from pre-WBRT CT and post-WBRT CT were assessed. Multiple variables were examined for correlation with volume reduction in the lumpectomy cavity. Results: The mean and median volume reduction in the lumpectomy cavity after WBRT were 17.6 $cm^3$ and 16.1 $cm^3$, respectively with the statistical significance (p < 0.001). The volume reduction in the lumpectomy cavity was inversely correlated with time from surgery to radiation therapy (R = 0.390). The presence of seroma was significantly associated with a volumetric change in the lumpectomy cavity after WBRT (p = 0.011). Conclusion: The volume of lumpectomy cavity reduced significantly after WBRT. As the time from surgery to the start ot WBRT increased, the volume reduction in the lumpectomy cavity during WBRT decreased. A strong correlation was observed between the presence of seroma and the reduced volume. To ensure appropriate coverage and to limit normal tissue exposure during boost irradiation in patients who has seroma at the time of starting WBRT, repeating CT simulation at boost planning is suggested.

Evaluation on Cavity Expansion under Pavement based on Groundwater Injection test (지하수 주입실험을 통한 도로노면 하부의 공동 확장 평가)

  • Park, Jeong-Jun;You, Seung-Kyong;Hong, Gigwon
    • Journal of the Korean Geosynthetics Society
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    • v.18 no.3
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    • pp.79-88
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    • 2019
  • This study described a results of groundwater injection test in cavity, in order to evaluate characteristics of cavity expansion under pavement. That is, groundwater amount proportional to the cavity volume was injected into the generated cavity step by step, and then the cavity with the changed size was monitored as the injected groundwater was drained. The test result showed that the cavity volume by groundwater injection increased, and then it converged or decreased. This means that some of the relaxation soil around the cavity collapsed, and the fine-grained soils in some soils filled the void in the surrounding soils when the cavity is expanded by groundwater injection. The volume change and expansion characteristics of the cavity according to the groundwater injection step were analyzed. The result showed that the cavity extended laterally. Therefore, it was found that the cavity expansion is caused by the repetition of the relaxation soil collapse due to the groundwater flow and the loss of the collapsed soil below the cavity.

CHANGES IN HYOID BONE AND TONGUE POSITIONS, AND ORAL CAVITY VOLUME AFTER MANDIBULAR SETBACK BY SAGITTAL SPLIT RAMUS OSTEOTOMY

  • Liang, Shan-Shan;Chu, Yeon-Gyu;Choi, So-Young;Lee, Sang-Han;Park, In-Suk;Deng, Fang-Cheng
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.31 no.4
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    • pp.294-305
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    • 2009
  • Purpose: This retrospective study evaluated the changes in hyoid bone and tongue positions as well as oral cavity volume after mandibular setback by BSSRO. Materials and Methods: 18 Koreans who underwent BSSRO to correct mandibular prognathism were studied. Lateral cephalograms were taken and traced preoperatively (T0), immediately (T1) and approximately 6 months postoperatively (T2). Submentovertex radiograghs were taken and traced before surgery (T0) and about 6 months after surgery (T2). The area and volume of oral cavity, the vertical and horizontal dimensions of the hyoid bone and tongue dorsum were measured. Results: Mandibular setback surgery resulted in a significant reduction of lower oral cavity volume. The hyoid bone displaced posteroinferiorly immediately after surgery, and it tended to return to its original vertical position at 6 month after mandibular setback by BSSRO. The retropalatal space around tongue was maintained and the retrolingual space around tongue was reduced immediately postoperatively. The readaptation of tongue was not evident for that the follow up period was not long enough. No significant statistical correlations between the amounts of mandibular setback and the changes of oral cavity volume were observed. Conclusion: Mandibular setback surgery resulted in a significant reduction of lower oral cavity volume, which was most likely attributable to the posterior movement of the mandible. More subjects and long-term observations should be performed to assess the changes of oropharyngeal configuration following mandibular setback surgery.

mechanical properties of Al-Cu-Zr alloy parts by superplastic forming (Al-Cu-Zr 합금 초소성 성형품의 기계적 성질)

  • 이영선
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1999.03b
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    • pp.163-170
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    • 1999
  • Although the bulge forming technique is currently employed in commercial superplastic forming processes, the uniaxial tensile test is still the most commonly used method for the evaluation of the superplasticity of materials due to its simplicity in testing. However, the results obtained from the uniaxial tensile test can not be applied in analyzing the characteristics of the real parts formed in multi-axial stress state. In this paper, using the tensile test specimen obtained from the square cup manufactured by superplastic forming, tensile strength and elongation have been investigated according to the strain and cavity volume fraction. From the result of experiment, tensile strength and elongation are decreased according to the strain and cavity in Al-6%Cu-0.4%Zr alloy. On condition of uniaxial stress, cavity volume fraction is increased on linear according to the increasement of thickness strain. However, on condition of biaxial stress there are critical point( E t=1.5-1.6) that the slope, the ratio of cavity volume fraction and strain, have been changed. Therefore, cavity volume fraction is different with respect to stress condition, although the same strain.

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A Study on the Change of Cavity Area through Groundwater Injection Test under Pavement Cavity (도로하부 공동 내의 지하수 주입 실험을 통한 공동 영역 변화 연구)

  • Kim, Sang Mok;Choi, Hyeon;Yoon, Jin Sung;Park, Jeong Jun
    • Journal of the Society of Disaster Information
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    • v.16 no.2
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    • pp.267-275
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    • 2020
  • Purpose: In this study, GPR exploration equipment, spray vehicles and flow meters, core drill, borehole image processing system(BIPS), 3D cavity imagery equipment, and cavity formatting equipment were used to identify this cavity growth process. Method: A certain amount of water was injected in proportion to the mass of the cavity, and the cavity was observed to expand as the injected water was drained out. The cavity rating change was evaluated by quantitatively evaluating the expansion factors and the speed of growth. Results: According to the results of examining the volume change through injection time - injection flow rate - volume increase for the four experimenters, the volume increase decreased as the injection time increased, and there was no further increase in volume if injected for one hour or so. Conclusion: In addition, the injection test analyzed the volumetric variation to determine whether the cause of the cavity occurrence was the effect of the underground burial in the vicinity of the cavity. Therefore, it was found that the cavity expansion is caused by the repetition of the relaxation soil collapse due to the groundwater flow and the loss of the collapsed soil below the cavity.

3-D Representation of Cavity Region from Ultrasonic Image Acquired in the Time Domain (시간 영역에서 획득된 초음파 영상의 심내강 영역에 대한 3차원 표현)

  • Won, C.H.;Chae, S.P.;Koo, S.M.;Kim, M.N.;Cho, J.H.
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.05
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    • pp.119-122
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    • 1997
  • In this paper, we represented the variation of heart cavity area in the space domain by 3-d rendering. We arranged the 2-d sequence of ultrasonic image acquired in the time domain as volumetric data, and extracted heart cavity region from 3-d data. For the segmentation of 3-d volume data, we extracted the cavity region using the method of expanding the cavity region that is same statistical property. By shading which is using light and object normal vector, we visualized the volume data on image plane.

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Experimental/Computational Study on the Supersonic Cavity Flow with a Sub-Cavity to Reduce the Pressure Oscillation (압력진동을 저감하기 위한 sub-cavity를 가진 초음속 공동유동에 대한 실험 및 수치해석적 연구)

  • Lim, Chae-Min;Lee, Young-Ki;Kim, Heuy-Dong
    • Proceedings of the KSME Conference
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    • 2007.05b
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    • pp.3009-3014
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    • 2007
  • The effectiveness of passive control techniques for alleviating the pressure oscillation generated in a supersonic cavity flow was investigated numerically and experimentally, respectively. The control device includes a sub-cavity installed near the leading edge of a rectangular cavity. Time-dependent supersonic cavity flow characteristics with turbulent features were examined by using the three-dimensional, mass-averaged Navier-Stokes computation based on a finite volume scheme and large eddy simulation. The results show that the pressure oscillation near the trailing edge dominates overall time-dependent cavity pressure variations. Such an oscillation can be attenuated more significantly in the presence of the sub-cavity compared with the cavity without sub-cavity, and a larger sub-cavity leads to better control performance.

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A Feasibility Study on In-Vessel Core Debris Cooling through Lower Cavity Flooding

  • Yang, Soo-Hyung;Baek, Won-Pil;Chang, Soon-Heung
    • Proceedings of the Korean Nuclear Society Conference
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    • 1996.11a
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    • pp.309-314
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    • 1996
  • Feasibility study has been accomplished to evaluate the effectiveness of the in-vessel core debris cooling through lower cavity flooding using two dimensional finite difference scheme. The volume of cerium pool and decay power rate generated in corium pool were evaluated as important parameters to the temperature distribution on the reactor vessel lower head through previous works. In this study, the corium volume based on the System 80+ core structure and time dependent decay power rate are considered for feasibility evaluation. In addition, preliminary plans for the in-vessel core debris cooling through lower cavity flooding as severe accident management strategy, i.e. flooding timing, method and capacity, are suggested based on the result of the numerical study, international tendency related to in-vessel core debris cooling through lower cavity flooding.

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Effect of a Magnetic Field on Mixed Convection of a Nanofluid in a Square Cavity

  • Sheikhzadeh, G.A.;Sebdani, S. Mazrouei;Mahmoodi, M.;Safaeizadeh, Elham;Hashemi, S.E.
    • Journal of Magnetics
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    • v.18 no.3
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    • pp.321-325
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    • 2013
  • The problem of mixed convection in a differentially heated lid-driven square cavity filled with Cu-water nanofluid under effect of a magnetic field is investigated numerically. The left and right walls of the cavity are kept at temperatures of $T_h$ and $T_c$ respectively while the horizontal walls are adiabatic. The top wall of the cavity moves in own plane from left to right. The effects of some pertinent parameters such as Richardson number (ranging from 0.1 to 10), the volume fraction of the nanoparticles (ranging 0 to 0.1) and the Hartmann number (ranging from 0 to 60) on the fluid flow and temperature fields and the rate of heat transfer in the cavity are investigated. It must be noted that in all calculations the Prandtl number of water as the pure fluid is kept at 6.8, while the Grashof number is considered fixed at 104. The obtained results show that the rate of heat transfer increases with an increase of the Reynolds number, while but it decreases with increase in the Hartmann number. Moreover it is found that based the Richardson and Hartmann numbers by increase in volume fraction of the nanoparticles the rate of heat transfer can be enhanced or deteriorated compared to the based fluid.