• Title/Summary/Keyword: Flow failure

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Implementation on the Uroflowmetry System and Usefulness Estimation of the Uroflow Parameters (요류검사 시스템의 구현과 요류파라미터의 유용성 평가)

  • Han, B.H.;Jeong, D.U.;Kim, U.Y.;Bae, J.W.;Shon, J.M.;Kim, J.H.;Park, J.M.;Chung, M.K.;Jeon, G.R.
    • Proceedings of the IEEK Conference
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    • 2002.06e
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    • pp.293-296
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    • 2002
  • In this study, the object is a development on uroflowmetry system to detect a voiding symptom conveniently in home or hospital. The hardware was composed of mechanism and system circuit part, the software was divided into firmware and PC program part. The following experiment was performed to evaluate an ability of classification and fitness. First, the following parameters was calculated in each flow curve pattern. The parameters are MFR, AFR, VOL, VT, FT, and TMF. A significant difference among parameters was examined through a statistical analysis for extracted parameters between normal and abnormal group. In the next work, the following experimentation was performed to classify the voiding symptom. Analysis of congregate rate was examined to find out classification possibility about each symptom of BPH, voiding difficulty, detrusor failure and hyperreflexia, unstable bladder. The uroflow data with the above symptom was divided into normal and abnormal group using fuzzy classifier. and that was performed appending the other group again. Fuzzy classification result using MFR and AFR was superior by 89.6 % more than grouping evaluation including VOL.

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Analysis of Rainfall Characteristics and Landslides at the West Side Area of Gangwon Province (강원 영서지역 산사태 및 강우특성 분석)

  • Yoo, Namjae;Yoon, Daehee;Um, Jaekyung;Kim, Donggun;Park, Byungsoo
    • Journal of the Korean GEO-environmental Society
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    • v.13 no.9
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    • pp.75-82
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    • 2012
  • This paper is the results of analysis for the causes and characteristics of landslide according to heavy rain occurred in west area of Gangwon province which is affected by typhoon such as Ewiniar and Bilis in 2006. West side of Gangwon province is topographically weak for the landslide and debris flow since it is covered by soil of weathered rock such as Gneiss and Granite. From the results of analysis for the rainfall characteristics, it was found that landslide occurrence is closely related to the accumulated rainfall amount less than 3 days. Furthermore, it was found that regional difference of occurrence frequency is effected by 1-hour maximum rainfall intensity. From the results of analysis for the landslide data of 860 locations occurred in west side, it was shown that failure mode was changed from transition slide to liquidity slide. Occurrence frequency was high at the slope angle of $20{\sim}30^{\circ}$ slope length of 11~20, and slope width of 6~10. Landslide of west side is the typical landslide of Gneiss and Granite and the type of small scale which has narrow slope width.

Behavior of Flexible Pipes with the Accelerated Flowable Backfill Materials Using Surplus Soil for Underground Power Utilities (굴착잔토를 재활용한 지중 전력케이블 유동성 뒷채움재 이용시 지중연성관의 거동특성)

  • Oh, Gidae;Kim, Daehong;Lee, Daesu;Kim, Kyoungyul;Hong, Sungyun
    • Journal of the Korean GEO-environmental Society
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    • v.10 no.7
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    • pp.33-41
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    • 2009
  • In the case of underground power utilities pipe such as circular pipe, the most difficult problem is low compaction efficiency of the bottom of pipe inducing the failure of utilities. To overcome this problem, various studies have been performed and one of these is CLSM (controlled low strength materials) accelerated flow ability. CLSM has already been stage of commercial use in the foreign countries led by power company. In this study, we estimated the behavior of flexible pipe with flowable backfill materials and sand to compare on the DB24 load. The results showed that the deformation of flexible pipe is affected by types of backfill materials. CLSM shows better behavior characteristics than compacting sand. But numerical and analytical results that peformed to compare to the field test results showed big gap with the field results.

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A New Quantification Method of Rock Joint Roughness (I) - A Close Assessment of Problems (암석 절리면 거칠기의 정량화에 대한 연구 (I) - 문제점의 규명)

  • Hong, Eun-Soo;Nam, Seok-Woo;Lee, In-Mo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.7 no.4
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    • pp.269-283
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    • 2005
  • To figure out the cause of underestimating the roughness and shear strength of rock joints suggested by numerous researchers, we analyzed roughness mobilization characteristics, characteristics of roughness parameters, effects of sampling interval, and waviness for roughness parameters. It was found out that lack of understanding of the roughness mobilization characteristics, inappropriate applications of roughness parameters, and effect of aliasing provide a main reasons for those problems. Several practical alternatives for improving those problems were suggested. As far as digitizing methods are concerned, we can find that using a 3D scanner can give a relatively effective result. To avoid aliasing, sampling interval should be less than one-quarter of the minimum asperities. As for the quantification of roughness, it was analyzed that the roughness parameter should be classified into two components depending on the scale of roughness to apply the shear strength model. For classifying the roughness, a framework of the criterion was suggested based on the plastic flow concept for the asperity failure, and the basis for proposing a new alternative shear strength model was established.

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Effects of Manual Lymph Drainage on Patients with Secondary Lymphedema of Legs After Gynecologic Cancer (부인과 암 이후 이차적인 다리 림프 부종 환자에게 적용한 림프흡수 마사지의 효과)

  • Jeong, Seong-gwan;Lee, Seung-byung
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.22 no.2
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    • pp.35-39
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    • 2016
  • Background: The superficial lymphatic system is divided into areas called lymphatic territories which are separated by watersheds. When the lymphatic system fails to remove its load either due to surgery, radiotherapy or some congenital malformation of it then the fluid and the proteins and wastes contained within it accumulates in that territory. Anastomotic connections exist across the watersheds and while they can work unaided manual lymph drainage (MLD) can significantly help drainage across them into unaffected lymphatic territories. The purpose of the study is to examine the effectiveness of a manual technique in moving fluids and softening hardened tissues using a tape measure and Patient-Specific Functional Scale. Methods: We examined the movement of fluids from the affected limbs of lymphedema patients who underwent a standardized 30-min treatment using the Dr. Vodder method of MLD. We chose a typical cross section of patients with secondary leg or secondary arm lymphedema. The lymphedema patient was also measured after the conclusion of treatment and underwent a follow-up control measurement, within 8 weeks. Both evaluation tools indicated a movement of fluid to different and unblocked lymphatic territories as well as a softening of tissues in some of the affected limbs. Results: MLD is an effective means of fluid clearance when it accumulates as a consequence of a failure of the lymphatic system. It seems likely that MLD has a systemic effect on the lymphatic system and that it can improve flow from otherwise normal tissues. Conclusions: It is hypothesized that a series of treatments would result in even more significant improvements.

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Perfusion-Weighted MRI Parameters for Prediction of Early Progressive Infarction in Middle Cerebral Artery Occlusion

  • Kim, Hoon;Kim, Yerim;Kim, Young Woo;Kim, Seong Rim;Yang, Seung Ho
    • Journal of Korean Neurosurgical Society
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    • v.59 no.4
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    • pp.346-351
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    • 2016
  • Objective : Early progressive infarction (EPI) is frequently observed and related to poor functional outcome in patients with middle cerebral artery (MCA) infarction caused by MCA occlusion. We evaluated the perfusion parameters of magnetic resonance imaging (MRI) as a predictor of EPI. Methods : We retrospectively analyzed patients with acute MCA territory infarction caused by MCA occlusion. EPI was defined as a National Institutes of Health Stroke Scale increment ${\geq}2$ points during 24 hours despite receiving standard treatment. Regional parameter ratios, such as cerebral blood flow and volume (rCBV) ratio (ipsilateral value/contralateral value) on perfusion MRI were analyzed to investigate the association with EPI. Results : Sixty-four patients were enrolled in total. EPI was present in 18 (28%) subjects and all EPI occurred within 3 days after hospitalization. Diabetes mellitus, rCBV ratio and regional time to peak (rTTP) ratio showed statically significant differences in both groups. Multi-variate analysis indicated that history of diabetes mellitus [odds ratio (OR), 6.13; 95% confidence interval (CI), 1.55-24.24] and a low rCBV ratio (rCBV, <0.85; OR, 6.57; 95% CI, 1.4-30.27) was significantly correlated with EPI. Conclusion : The incidence of EPI is considerable in patients with acute MCA territory infarction caused by MCA occlusion. We suggest that rCBV ratio is a useful neuro-imaging parameter to predict EPI.

Development of Hardware Design Process Enhancement Tool for Flight Control Computer using Modeling and Simulation (M&S 기반의 비행조종컴퓨터 하드웨어 설계 프로세스 개선을 위한 툴 개발)

  • Kwon, Jong-Kwang;Ahn, Jong-Min;Ko, Joon-Soo;Seung, Dae-Beom;Kim, Whan-Woo
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.35 no.11
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    • pp.1036-1042
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    • 2007
  • It is rather difficult to improve flight control computer(FLCC) hardware(H/W) development schedule due to lack of commercial off-the-self(COTS) tools or target specific tools. Thus, it is suggested to develop an enhanced process utilizing modeling, simulation and virtual reality tools. This paper presents H/W design process enhancement tool(PET) for FLCC design requirements such as FLCC input/output(I/O) signal flow, I/O fault detection, failure management algorithm, circuit logic, PCB assembly configuration and installation utilizing simulation and visualization in virtual space. New tool will provide simulation capability of various FLCC design configuration including shop replaceable unit(SRU) level assembly/dis-assembly utilizing open flight format 3-D modeling data.

Ectopic EBP2 expression enhances cyclin E1 expression and induces chromosome instability in HEK293 stable clones

  • Lee, Ming-Cheng;Hsieh, Chang-Hsun;Wei, Shu-Chen;Shen, Shu-Chen;Chen, Chiung-Nien;Wu, Vin-Cent;Chuang, Li-Ying;Hsieh, Fon-Jou;Wu, C. H. Herbert;Tsai-Wu, Jyy-Jih
    • BMB Reports
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    • v.41 no.10
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    • pp.716-721
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    • 2008
  • To explore the effects of deregulated expression of the EBNA1 binding protein 2 (EBP2) on cell growth, we generated human HEK293 stable clones constitutively expressing an EBP2-EGFP fusion protein. We found both RNA and protein levels of cyclin E1, a dominant oncoprotein, were elevated in the EBP2- EGFP stable clones. These findings were confirmed by flow cytometry bivariate analysis of cyclin expression versus DNA content. Moreover, the increase in p21 expression and the specific phosphorylation at Ser1981 of ATM and Ser15 of p53 were also observed in these stable clones, and these observations may explain the failure to observe an increase in Cdk2 kinase activity. In addition, after one year of passage culture, the EBP2-EGFP stable clones tended to lose 4 to 5 chromosomes per cell when compared to that of control cells. All of these findings provide a possible link between deregulated expression of EBP2 and tumor development.

Temporal Change of Fluvial Geomorphology in the Middle Reaches of the Sumjin River, Korea (섬진강 중류 (곡성-순창) 구간의 하천지형 변화 연구)

  • 남욱현;양동윤;김주용;김진관
    • The Korean Journal of Quaternary Research
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    • v.16 no.1
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    • pp.17-27
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    • 2002
  • Analysis of No. 199∼145 cross-sections set up by the Ministry of Construction (1978) in the middle reaches of the Sumjin River around Sunchang, Daegang, and Goksung areas have been done for delineating the changes In fluvial geomorphic features. The entire river-bed in the study area has been considerably degraded since 1978. In some cross-sections, the thalweg shillings are observed. Two aspects are responsible for the erosion-dominant environment. First, flow velocity has been increased. Human activities including wetland destruction, ex-channel destruction and artificial levee construction reduced the channel width, and fixed the channel geometry. This has resulted in increase of the water velocity. Pebble and granule∼coarse sand are prevailing on the river-bed, indicate the high speed of the currents. Second, aggregate has been intensively mined during 1980s∼1990s around the areas. Especially, in the right side of the cross-sections No. 188∼187 and the left side of the cross-section No. 155, erosion toward under the artificial levee is remarkable. This can be led to bank failure in case of heavy rainfall.

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Micromechanical Model for the Consolidation Behavior in SiC-Ti Metal Matrix Composites (SiC-Ti금속기 복합재료의 강화거동에 관한 미시역학적 모델)

  • 김준완;김태원
    • Composites Research
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    • v.16 no.3
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    • pp.1-8
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    • 2003
  • Densification occurs by the inelastic flow of the matrix materials during the consolidation processes at high temperature for MMCs, and the results depend on many process conditions such as applied pressure, temperature and volume fraction of fiber and matrix materials. This is particularly important in titanium matrix composites since material failure may occur by either the applied conditions or microstructural parameters through the processes, and thus a generic model based on micro-mechanical approaches enabling the evolution of density over time to be predicted has been developed. The mode developed is then implemented into FEM so that practical process simulation has been carried out. Further the experimental investigation of the consolidation behavior of SiC/Ti-6Al-4V composites using vacuum hot pressing has been performed, and the results obtained are compared with the model predictions.