• Title/Summary/Keyword: Volume reduction

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Evaluation of Masseter Muscle Volume after Contouring of Prominent Mandible Angle by Measurement of CT Scan Image

  • Kim, Yong Oock;Choi, Jong Woo
    • Journal of International Society for Simulation Surgery
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    • v.1 no.2
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    • pp.71-74
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    • 2014
  • Purpose The prominent mandible angle, otherwise known as "square face", has been recognized as an aesthetic problem that needs correction by many in the Asian community. Many surgeons considered that mandible angle ostectomy alone, brings about hypotrophy of the masseter muscle. However, it was only proven indirectly (by clinical experience and histological animal experiments) and not objectively. In this study, we evaluated the volume of masseter muscle to prove the effect, objectively. Materials and method Computed tomography (CT) images were used to measure the masseter muscle volume of normal female group (n=6), and of female patient group n=8, preoperative and early & late postoperative volumes) presenting the symptom of prominent mandible angle. The data was analyzed statistically by two-sample t-test and paired t-test using SAS (version 8.2). Results In normal female group, volume average was $16,142{\pm}2,829.8mm^3$. In patient group, preoperative volume averaged $24,447{\pm}4,544.5mm^3$ (p<0.0001), early postoperative volume measured average of $31,966{\pm}50,421mm^3$ which is a 30% increase from the preoperative volume (p<0.0001). Late postoperative measurement was $20,202{\pm}4,092.3mm^3$, which is a 20% decrease from the preoperative volume (p<0.0006). Conclusion The bone reduction of prominent mandible angle induce the hypotrophic effect of masseter muscle after long term follow up (5 more months). This result mean that the result of mandible angle contouring surgery can be considered as combined effect of bony angle reduction and subsequent masseter muscle hypotrophy.

Volumetric analysis of normal condyles and those with disc displacement with reduction in the Indonesian population: A CBCT study

  • Nawawi, Azkya Patria;Rikmasari, Rasmi;Kurnikasari, Erna;Oscandar, Fahmi;Lita, Yurika Ambar
    • Imaging Science in Dentistry
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    • v.52 no.1
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    • pp.103-108
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    • 2022
  • Purpose: Disc displacement can cause resorption of the head of the condyle and affect its volume. This study analysed the volume of normal condyles and those with disc displacement with reduction (DDR) in cone-beam computed tomography (CBCT) scans from the Indonesian population. Materials and Methods: This study analysed 56 condyles (26 normal and 30 with DDR) from patients who visited the Oral and Maxillofacial Radiology Unit after being referred from the Prosthodontics Unit at Dental Hospital Universitas Padjadjaran from December 2020 to February 2021. Samples were divided into 2 groups (normal and DDR left and right-side condyles) based on the DC/TMD Axis 1 form through the clinical examination results. Both sample groups were exposed to CBCT radiation. The CBCT imaging results in the Digital Imaging and Communications in Medicine format were exported to the open-source ITK-SNAP format to determine condyle volume. Volumetric data from the cortical and trabecular areas of the right or left side condyles were arranged by sex. The independent t-test was used to determine the significance of differences with IBM SPSS version 21.0. Intra- and inter-observer reliability and validity were tested before determining the volume of the condyles. Results: Normal condyles and DDR condyles showed significant differences in volume (P<0.05). Significant differences were also seen in cortical (P=0.0007) and trabecular (P=0.0045) volumes. There was a significant difference in condylar volume based on sex. Conclusion: The normal condyle volume was significantly different from the DDR condyle volume in both sexes.

Noise Reduction Effect of an Air Bubble Layer on an Infinite Flat Plate (무한 평판 주위에 형성된 수중 기포층의 방사소음 감소 효과)

  • Kim, Jong-Chul;Oh, Joon-Seok;Cho, Dae-Seung
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.17 no.2 s.119
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    • pp.168-176
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    • 2007
  • The mixture sound speed in bubbly fluids is highly dispersive due to differences of the density and compressibility between bubbles and fluids. The dispersion range in bubbly fluids expands to a higher frequency than the resonance frequency of an air bubble. A theoretical model was developed to compute the reduction of radiation noise that is generated by a force applied on an infinite flat plate using a bubble layer as a compliant baffle. For evaluating the effectiveness of a bubble layer in reducing the structure-borne noise of an infinite elastic plate, the noise reduction levels for various parameters such as the thickness of bubble layers, the volume fractions and the distribution types of bubbly fluids are calculated numerically. The noise reduction effect of an air bubble layer on an infinite flat plate is considerable level and similar to the tendency of dispersion of bubbly fluids. It is recommended that the thickness of a bubble layer should be increased with keeping an appropriate volume fraction of an air bubble for the most effective reduction of the radiation noise.

Evaluation of Water Cycle Improvement in LH Institute Using SWMM-LID Model (SWMM-LID 모델을 이용한 토지주택연구원의 물순환 개선효과 평가)

  • Jung, Jong-Suk;Jung, Kwang-Wook;Kang, Suman;Hyun, Kyong-Hak
    • Journal of Korean Society on Water Environment
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    • v.34 no.3
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    • pp.308-315
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    • 2018
  • SWMM-LID was calibrated with flow monitoring data in LHI to evaluate runoff after LID application. The flow rate in the B basin was estimated to be 0.94 and 6.15 for O/S and $D_v$, respectively. In the A and C basins, the difference between the observed and simulated data was greater than in the B basin. As a result of runoff reduction efficiency by the application of LID facilities, the change of infiltration increased from 34.6 % to 45.8 % in the entire watershed, and the runoff decreased from 58.8 % to 46.3 %. In the runoff reduction of each LID facility, rain garden E showed the highest effect with 99.9 % and bioretention B showed the lowest effect with 27.5 %. In order to evaluate the efficiency of each LID facility, a comparison is made between the pore volume (V) of the LID and the catchment area (A). The runoff showed a runoff reduction effect of about 70 % above the 0.1 volume/area (V/A) value. As a result of examining the runoff reduction with LID facilities by the LID module of SWMM, a reasonable design is possible by reflecting the appropriate LID volume to drainage area.

The effect of cold rolling reduction ratio on the texture evolution in Al-5% Mg alloy (Al-5%Mg 합금 판재의 집합조직 발달에 미치는 냉간 압하율의 영향)

  • Choi, J.K.;Kim, H.W.;Kang, S.B.;Choi, S.H.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2008.10a
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    • pp.102-105
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    • 2008
  • To investigate the evolution of deformation texture during cold rolling deformation, cold rolling process on a commercial Al-5% Mg sheet was carried out at different rolling reduction ratio. The evolution of annealing texture in cold-rolled Al-5% Mg sheet was also investigated. The evolution of recrystallization texture during annealing process strongly depends on the rolling reduction ratio before heat treatment. Visco-plastic self-consistent (VPSC) polycrystal model was used to predict r-value anisotropy of the cold-rolled and annealed Al-5% Mg sheets. The change of volume fraction for the major texture components was also analyzed.

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Study on the determination of optimum size of storage tank and intercepting capacity for CSOs reduction in urban area (도시지역 CSOs 저감을 위한 저류조 및 이송관로의 최적 용량결정에 관한 연구)

  • Lee, Kwan Yong;Choi, Won Suk;Lee, Yong Jae;Koo, Won Suk;Song, Chang Soo
    • Journal of Korean Society of Water and Wastewater
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    • v.26 no.6
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    • pp.735-745
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    • 2012
  • Storage method is one of major measures for reduction of CSOs pollutant loads and several projects have been done nationwide. But systematic analysis of intercepting capacity has not been studied to determine optimum size of storage facility. In this research, not only storage volume but also intercepting capacity which means flow capacity from intercepting facility to CSOs storage facility was studied and optimum sizing method for storage facility was proposed. The result shows that pollutants reduction efficiency can be increased significantly by increasing intercepting capacity and it might reduce storage volume and total construction costs. Intercepting capacity for the study area was evaluated and it was shown as equivalent to 83 % probability rainfall intensity.

Effects of Washing of Food Wastes on Aerobic Composting (음식물쓰레기의 세척이 호기성 퇴비화에 미치는 영향)

  • 박석환
    • Journal of Environmental Health Sciences
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    • v.30 no.1
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    • pp.1-6
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    • 2004
  • This study was performed to estimate the effects of washing of food wastes on temperature, pH, weight and volume reduction and salinity in aerobic composting of food wastes. Weight ratios of food wastes to water in washing were 1:0(Control), 1:1 (W-1), 1:2(W-2), 1:3(W-3) and :4(W-4), respectively. Ratios of food wastes to wood chips in reactor of Control, W-1, W-2, W-3 and W-4 were 5 kg:5 1, respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The increase in the ratio of food wastes to water used in washing resulted in the decrease of the highest reaction temperature and the elongation of the high temperature reaction period. The lowering of the ratio of food wastes to water used in washing resulted in faster pH increase and the steady state in the weight reduction rate and the volume reduction rate of composts. The final salinities of Control, W-1, W-2, W-3 and W-4 were 0.95%, 0.73%, 0.65%, 0.57% and 0.41%, respectively.

Analysis of Runoff Reduction Characteristics with LID Adaptation and LID Applicability at Bimodal Tram Route (LID 개념 적용으로 인한 유출 감소 특성 가능성 분석 및 바이모달 트램 전용노선에서의 적용성 검토)

  • Park, Jun-Ho;Park, Young-Kon;Yoon, Hee-Taek;Yoo, Yong-Gu;Kim, Jong-Gun;Park, Youn-Shik;Lim, Kyoung-Jae
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.147-150
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    • 2008
  • Changes in land uses at urbanizing areas are causing flooding, increase in NPS pollutants. Thus, Low Impact Development (LID) concept is now being employed in urban planning for sustainable development. Compared with the conventional BMPs, the LID is a new concept in urban planning to minimize the impacts of urbanization for site-specific LID IMPs. The objective of this study is to analyze the efficiency of LID adoption in study watershed in peak rate runoff and runoff volume reduction perspectives. The analysis revealed that the peak rate runoff and runoff volume decreased significantly with the LID adoption. This indicates that the Bimodal tram route with grass installed at the center of the road will contribute reduction in surface runoff and peak rate runoff, and also in NPS pollutant generation from the Bimodal tram route.

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Numerical analysis of drag reduction of turbulent flow in a pipe (원관내 난류의 저항감소현상에 대한 수치해석)

  • 홍성진;김광용;최형진
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.11 no.6
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    • pp.733-739
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    • 1999
  • A modified low-Re $k-\varepsilon$ model is used for the calculation of drag-reducing turbulent flow by polymer injection in a pipe. With the viscoelastic model, molecular viscosity in the definition of turbulent viscosity is related to elongations viscosity of the solution to account for the effects of drag reduction. Finite volume method is used for the discretization, and power-law scheme is used as a numerical scheme. Computed dimensionless velocity profiles are in good agreements with the experimental data in case of low drag reductions. However, in case of high drag reductions, they deviate largely from the measurements in the central zone of the flow field.

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A Study on Air Temperature Reduction Effect and the Functional Improvement of Street Green Areas in Seoul, Korea (서울 도심 가로수 및 가로녹지의 기온 저감 효과와 기능 향상 연구)

  • Jung, Hee-Eun;Han, Bong-Ho;Kwak, Jeong-In
    • Journal of the Korean Institute of Landscape Architecture
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    • v.43 no.4
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    • pp.37-49
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    • 2015
  • The goal of this research is to examine air temperature changes according to tree type, plantation type, roadside green area structure, and green volume of street green area within a city. The plantation type that could be analyzed for comparison by tree type with over 3 species was 1 rows of tree+shrubs. The results of analysis of average air temperature difference between pedestrian and car streets vis-a-vis 1 row of tree+shrub in high air temperature areas were: Pinus densiflora, $1.35^{\circ}C$; Zelkova serrata, $1.84^{\circ}C$; Ginkgo biloba, $2.00^{\circ}C$; Platanus occidentalis, $2.57^{\circ}C$. This standard large wide canopy species was analyzed by the roadside to provide shade to have a significant impact on air temperature reduction. In terms of analysis of the relationship between plantation type of roadside trees and air temperature, the average air temperature difference for 1 row of tree type was $1.80^{\circ}C$; for 2 rows of trees it was $2.15^{\circ}C$. In terms of analysis of the relationship between the roadside green area structure and air temperature, for tree type, average air temperature $1.94^{\circ}C$: for tree+shrub type, average air temperature $2.49^{\circ}C$; for tree+mid-size tree+shrub type, average air temperature $2.57^{\circ}C$. That is, air temperature reduction was more effective in a multi-layer structure than a single layer structure. In the relationship analysis of green volume and air temperature reduction, the air temperature reduction effect was enlarged as there was a large amount of green volume. There was a relationship with the green volume of the road, the size of the tree and number of tree layers and a multi-layer structured form of planting. The canopy volume was large and there were a great number of rows of the tree layer and the plantation type of multi-layer structure, which is what is meant through a relationship with the green volume along the roadside. Green composition standards for air temperature reduction effects and functional improvement were proposed based on the result. For a pedestrian street width of 3m or less in the field being ideal, deciduous broadleaf trees in which the canopy volume is small and the structure of the tree+shrub type through the greatest 1m green bend were proposed. For a pedestrian street width of over 3m, deciduous broadleaf trees in which the canopy volume is large and is multi-layer planted with green bend over 1m, tree+mid-size tree+shrub type was proposed.