• Title/Summary/Keyword: Forced

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A Study on Air-Conditioning System for Excavator using Forced Exhaust (강제배기를 이용한 굴삭기 공기조화 시스템에 관한 연구)

  • Hwang, J.H.;Jeong, C.S.;Ko, J.H.;Yang, S.Y.
    • Journal of Drive and Control
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    • v.10 no.2
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    • pp.23-29
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    • 2013
  • The excavator is used in a variety of construction environments. There are many kinds of risk like falling rocks or harmful dust. The excavator cabin protects the operator not only from these harmful environments but also provides a comfortable working environment. By the way, the excavator cabin consumes a lot of energy for cabin air conditioner. For this reason, the research is required to reduce energy consumption. This study suggests the air conditioning system for excavator using forced exhaust. First, the forced exhaust system simulated by AMESim tool and surveyed the applicability. Using AMESim simulation, it was investigated the effect of cabin inside temperature by intake flow rate and intake air temperature. The experiment executed using the 1.5 ton excavator and field tested according to the intake flow rate. Finally, verified the applicability on the air conditioning system for excavator using forced exhaust.

Surgical exposure of impacted tooth for orthodontic forced eruption : case report (교정적 견인을 위한 매복치의 수술적 노출 방법에 관한 증례보고)

  • Choi, Yongkwan
    • Journal of the Korean Academy of Esthetic Dentistry
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    • v.28 no.2
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    • pp.86-94
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    • 2019
  • Tooth impaction make various problems which are pathologic changes, functional defect and esthetic troubles. Sometimes impacted tooth are extracted. But surgical exposure of impacted tooth and orthodontic forced eruption are usually used a lot to solve these problems. Impacted tooth for orthodontic treatment has two impacted patterns 1) Simple impaction outside alveolar bone covered soft tissue, 2) Fully impaction under alveloar bone. So I introduce way to exposure of impacted tooth for orthodontic treatment with various cases and literatures.

Changes in the Respiratory Function of Stroke Patients on the Ground and Immersed under Water (지상과 수중에서 뇌졸중 환자의 호흡기능 변화)

  • Kim, Ju-Seung;Park, Min-Chull
    • PNF and Movement
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    • v.16 no.3
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    • pp.389-395
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    • 2018
  • Purpose: The purpose of this study was to investigate whether the respiratory function of patients with stroke was different on the ground and under water. Methods: We recruited 14 adults who had experienced a stroke (12 male, 2 female) for our study. We measured forced vital capacity, forced expiratory volume at one second, maximum inspiratory pressure, and maximum expiratory pressure when the participants breathed on the ground and under water. On the ground, the participants were safely supported using a table and chair and were measured in a standing posture. For measuring under water, the participants were immersed in water in a standing position to clavicle height. The participants were measured while standing, and the assistant supported them when they needed help. The collected data were analyzed by a paired t-test. Results: Forced vital capacity and forced expiratory volume at one second were significantly lower in water than on the ground when breathing at maximum. Maximum inspiratory pressure was not significantly different when standing on the ground or in water, but maximum expiratory pressure was significantly higher in water than on the ground. Conclusion: It has been confirmed that the hydrostatic pressure affecting stroke patients immersed in water affects the forced expiratory volume at one second while reducing the forced vital capacity and increasing the maximum expiratory pressure.

Forced orthodontic eruption for augmentation of soft tissue prior to implant placement (임플란트 식립 전 연조직 증대를 위한 교정적 정출술)

  • Park, Chul-Wan
    • Journal of the Korean Academy of Esthetic Dentistry
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    • v.29 no.1
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    • pp.54-61
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    • 2020
  • Forced orthodontic eruption(FOE) is a non-surgical treatment approach that allows augmenting both soft- and hard-tissue profiles of potential implant sites, by forced orthodontic extrusion of "hopeless" teeth and their periodontal apparatus. By stretching the gingival and periodontal ligament fibers during extrusion, tension is imparted to the entire alveolar socket, stimulating osseous apposition at the alveolar crest. FOE increases the width of the attached gingiva, and the mucogingival junction remains stable when the gingival margin migrates coronally. Based on these effects, FOE of non-restorable teeth prior to implant placement is a viable alternative to conventional surgical augmentative procedures in implant site development. The aim of this case report is to describes coronal soft-tissue augmentation around fractured teeth, which was achieved by FOE before implant placement.

A Study on the Heat Sink with internal structure using Peltier Module In the Natural and Forced Convection (자연대류와 강제대류에서 펠티에 소자를 이용한 내부터널 구조를 가지는 히트싱크에 관한 연구)

  • Lee, Min;Kim, Tae-Wan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.7
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    • pp.4072-4080
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    • 2014
  • The Peltier Module has been used to dissipate the heat from electronic devices and electronic components. In this module, a heat sink is used to release the operating heat into the air outside. This study addressed the heat transfer characteristics for a heat sink with an inner tunnel. Under forced and natural convection conditions, the heat transfer characteristics were different. Therefore, the cooling and heating performances were studied for the heat sink, which has an inner tunnel. The heat transfer conditions were also evaluated by performing an experimental test, which investigated the heat transfer characteristics related to the variance in time and temperature distribution. Experiments on the heat transfer characteristics of the heat sink were conducted based on the forced and natural convection and temperature distribution changes. In the cooling experiment, the A- and B-shaped cooling pin heat sinks decreased the temperature of the forced convection than the temperature of natural convection. In the forced and natural convection, the A- and B-shaped decreased to a minimum of $-15^{\circ}C$. Under the forced and natural convection conditions, A- and B-shaped cooling pin heat sinks decreased the temperature when the voltage was increased. In the heating experiment, the A- and B-shaped cooling pin heat sinks increased the temperature of the forced convection than the temperature of natural convection. In forced convection, when the voltage was $15^{\circ}C$, the temperature of the A-shaped cooling pin heat sink increased to $150^{\circ}C$, and the temperature of the B-shaped cooling pin heat sink increased to $145^{\circ}C$. Under forced and natural convection conditions, the A- and B-shaped cooling pin heat sinks showed an increase in temperature with increasing voltage.

Effect of slow forced eruption on the vertical levels of the interproximal bone and papilla and the width of the alveolar ridge

  • Kwon, Eun-Young;Lee, Ju-Youn;Choi, Jeomil
    • The korean journal of orthodontics
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    • v.46 no.6
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    • pp.379-385
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    • 2016
  • Objective: Forced eruption has been proposed for the reconstruction of deficient bone and soft tissue. The aim of this study was to examine the changes in the alveolar ridge width and the vertical levels of the interproximal bone and papilla following forced eruption. Methods: Patients whose hopeless maxillary anterior teeth were expected to undergo severe bone resorption and soft tissue recession upon extraction were recruited. In addition, patients whose maxillary anterior teeth required forced eruption for restoration due to tooth fracture or dental caries were included. Before and after forced eruption, the interproximal bone height was measured by radiographic analysis, and changes in the alveolar ridge width and the interproximal papilla height were measured with an acrylic stent. Results: This prospective study demonstrated that the levels of the interproximal alveolar bone and papilla were significantly increased by 1.36 mm and 1.09 mm, respectively, in the vertical direction. However, the alveolar ridge width was significantly reduced by an average of 0.67 mm in the buccolingual direction. The changes in the level of the interproximal alveolar bone and papilla were positively correlated. Conclusions: Although the levels of the interproximal bone and papilla were significantly increased, the alveolar ridge width was significantly decreased following forced eruption. There was a modest positive and significant correlation between the changes in the height of the interproximal alveolar bone and the papilla. Based on our findings, modification of vertical forced eruption should be considered when augmentation of the alveolar ridge width is required.

Effect of Abdominal Drawing-In Maneuver on Peak Expiratory Flow, Forced Expiratory Volume in 1 Second and Pain During Forced Expiratory Pulmonary Function Test in Patients With Chronic Low Back Pain (만성요통환자에서 복부심부근 강화 운동이 노력성 호기 폐기능 검사 동안 최대호기유량 및 1초간노력성호기량과 요통에 미치는 효과)

  • Kim, Ki-Song;Kwon, Oh-Yun;Yi, Chung-Hwi
    • Physical Therapy Korea
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    • v.16 no.1
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    • pp.10-17
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    • 2009
  • The aim of this study was to investigate the effect of abdominal drawing-in maneuver (ADIM) on peak exploratory flow (PEF), forced exploratory volume in 1 second ($FEV_1$), and low back pain during forced expiration. Twenty-two subjects (14 subjects in experimental group, 8 subjects in control group) participated in this study. The stabilizer was used for ADIM training for five consecutive days. Vitalograph PEF/$FEV_1$ DIARY and visual analogue scale (VAS) were used to determine forced expiratory pulmonary function and low back pain, respectively. Independent t-test and analysis of covariance were used for statistical analysis with a significance level of .05. The findings of this study were as follows: 1) There were no significant differences of ADIM effect on PEF and $FEV_1$ between experimental group and control group. 2) There was a significant pain reduction in experimental group with ADIM. 3) PEF and $FEV_1$ increased significantly in the fifth day compared with the first day pre-exercise baseline. Therefore, it is concluded that ADIM was effective in improving PEF and $FEV_1$, and reducing VAS during forced expiration in patients with chronic low back pain.

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Correlations Between Height and Forced Expiratory Flow Curve Parameters (신장과 노력성 호기곡선 지표간의 상관성)

  • Jin, Bok Hee;Park, Sun Young;Park, Hyea Lim
    • Korean Journal of Clinical Laboratory Science
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    • v.36 no.2
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    • pp.199-204
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    • 2004
  • Height has become one of the most important factors to determine the pulmonary function test index, and there is a high correlation between them, so that they have been utilized for evaluating pulmonary function test predictive value or nomogram. Therefore, we have tried to find out that difference and if there is any correlation and linear relationship between height and forced expiratory flow curve. There were a total of 163 subjects, male 93 and female 70. This study was done at the Department of Pulmonary Function Test of Jeon-Ju Presbyterian Hospital and we measured the index at the forced expiratory flow curve of FVC, $FEV_{1.0}$, $FEV_{1.0}$/FVC, $FEF_{25-75%}$, and $FEF_{200-1200m{\ell}}$. When we subjected the group of height more than 160cm, there were gradual increments at FVC(p<0.001), $FEV_{1.0}$(p<0.001), $FEF_{25-75%}$(p<0.05) and $FEF_{200-1200m{\ell}}$(p<0.001), but no changes at $FEV_{1.0}$/FVC in terms of forced expiratory flow curve index. We have analyzed the relationship between height and forced expiratory flow curve, there was a close relationship at FVC(r=0.670, p<0.01), $FEV_{1.0}$(r=0.491, p<0.01), $FEF_{25-75%}$ (r=0.175, p<0.05) and $FEF_{200-1200m{\ell}}$(r=0.370, p<0.01) but there was reciprocal relationship at $FEV_{1.0}$/FVC(r=-0.215, p<0.01). We have tried simple regression analysis to see if height affects forced expiratory flow curve index as a sector, and the result was $FVC(\ell)=0.0642{\times}height(cm)-7.2978$(p<0.01, $R^2=0.449$), $FEV_{1.0}(\ell)=0.0407{\times}height(cm)-4.2774$ (p<0.01, $R^2=0.2411$), $FEV_{1.0}/FVC(%)=-0.2892{\times}height(cm)+121.44$(p<0.01, $R^2=0.0464$), $FEF_{25-75%}(\ell/sec)=0.0176{\times}height(cm)-0.7876$(p<0.05, $R^2=0.0237$), $FEF_{200-1200m{\ell}}(\ell/sec)=0.0967{\times}height(cm)-11.037$(p<0.01, $R^2=0.1214$) this was approved statistically. According to this study, if height is taller than average, forced expiratory flow curve index were increased, there was a close relationship between height and forced expiratory flow curve, and there was a linear relationship as sector between height and forced expiratory flow curve index. Therefore, researches that study other factors such as sex, age, weight, body surface area, and obesity indexes other than height should be done to see if there are any further relationships.

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Similarity analysis of a forced uniform flow impinging on a rotating disk in a vapor deposition process (증착공정에서의 회전원판 정체점유동에 대한 상사해석)

  • Song, Chang-Geol;Hwang, Jeong-Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.21 no.3
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    • pp.371-379
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    • 1997
  • A theoretical study for a forced uniform flow impinging on a rotating disk, typically involved in Chemical Vapor Deposition(CVD) and Vapor-phase Axial Deposition(VAD) processes, has been carried out. A set of exact solutions for flow and temperature fields are developed by employing a similarity variable obtained from force balance on a control volume near the disk. The solutions depend on the rotating speed of the disk, .omega., and the forced flow speed toward the disk, a. For constant forced flow speed, the overall boundary layer thickness decreases when the rotating speed increases. Approximately 5%, 15%, and 30% decreases of the thickness are obtained for .omega./a = 2, 5, and 10, respectively, compared to the case of .omega./a = 0 (axisymmetric stagnation point flow). For constant rotating disk speed the boundary layer thickness immediately decreases as the forced flow speed increases, compared to the case of .omega./a .rarw. .inf. (induced flow near a rotating disk). Effects of .omega. and a on heat transfer coefficient are studied and explained with the boundary layer characteristics.

CASE REPORT ON FORCED ERUPTION FOR CLINICAL CROWN LENGTHENING IN MAXILLARY ANTERIORS (상악전치부에서 치아정출술을 이용한 치관연장의 증례보고)

  • Kim, Young-Jun;Ju, Jae-Ig;Ryue, Myung-Girl;Jin, Yu-Nam;Chung, Hyun-Ju
    • Journal of Periodontal and Implant Science
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    • v.25 no.1
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    • pp.111-120
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    • 1995
  • This case report presents two maxillary anterior cases for clinical crown lengthening by forced eruption. In the first case, clinical crown of maxillary right lateral incisor was almost lost by fracture. Forced eruption using intracoronal splint and elastic thread accomplished vertical root movement successfully. Then, post & core was inserted and final restoration was harmonious with adjacent teeth. In the second case, the crown portion of maxillary right central incisor was almost mutilated by secondary caries. Forced eruption using removable Hawley appliance and elastic accomplished vertical root movement successfully. Then, post & core was inserted and final restoration was placed. In conclusion, clinical crown lengthening by vertical root movement can be accomplished by a simple appliance without any sacrifice of periodontal support in selected patients. A clinical crown so created can be restored to adequate function and arch integrity without compromising adjacent teeth. Therefore, forced eruption is preferred in the anterior region of the dentition where esthetics is of major concern.

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