• Title/Summary/Keyword: closure method

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A Study on the Dynamic Stress Intensity Factor of Orthotropic Materials(II) A Study on the Stress Field, Displacement Field and Energy Release Rate in the Dynamic Mode III under Constant Crack Propagation Velocity (직교 이방성체의 동적 응력확대계수에 관한 연구 (II) 등속균열전파 속도하에서 동적모드 III 상태의 응력장, 변위장, 에너지해방률에 관한 연구)

  • 이광호;황재석;최선호
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.2
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    • pp.331-341
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    • 1993
  • The propagating crack problems under dynamic antiplane mode in orthotropic material is studied in this paper. To analyze the dynamic fracture problems by theoretical method or experimental method in orthotropic material, it is important to know the dynamic stress intensity factor in the vicinity of crack tip. Therefore the dynamic stress field and dynamic displacement field with dynamic stress intensity factor of orthotropic material in mode III were derived. When the crack propagation speed approachs to zero, the dynamic stress components and dynamic displacement components derived in this paper are identical to the those of static state. In addition, the relationships between dynamic stress intensity factor and dynamic energy release rate are determined by using the concept of crack closure energy with the dynamic stresses and dynamic displacements derived in this paper. Finally, the characteristics of crack propagation are studied with the properties of orthotropic material and crack speed. The variation of angle .alpha. between fiber direction and crack propagating direction and crack propagation speed fairly effect on stress component and displacement component in crack tip. The influence of crack propagation speed on the speed on the stress and displacement is greater in the case of .alpha.=90.deg. than in the case of .alpha.=0.deg. and the faster the crack propagation speed, the greater the stress value and displacement value.

Comparison of Nasalance Score Between Glottal and Oral Articulation in Children with Velopharyngeal Insufficiency (연인두 폐쇄부전 아동의 보상조음과 정조음에서의 비음치 비교)

  • Lee, Eun-Kyung;Son, Young-Ik
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.18 no.2
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    • pp.129-133
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    • 2007
  • Background and Objectives: Nasometry is an easy, noninvasive method to obtain objective data regarding the function of velopharynx. However, because articulation errors may affect the results of nasometry, the examiner should interpret the nasalance score based on appropriate speech stimuli. The purpose of this study is to examine the difference of nasalance score between glottal and oral articulations in patients with velopharyngeal insufficiency (VPI). Materials and Method: Nineteen children between 3.4 and 12.1 years of age (mean age 5.7 years) with a confirmed VPl showing hypernasality and articulation errors (glottal stops) were included. Nasalance scores were obtained for two speech patterns of glottal and oral stops. In addition, the velopharyngeal functions were analyzed in four subjects using video nasopharyngoscopy. Results: The $mean{\pm}S.D$ nasalance scores of the glottal stops and oral stops were $42.54{\pm}16.26%$ and $25.47{\pm}16.51%$ respectively (p=.000). Six of 19 patients achieved normal nasalance scores when glottal stops changed to oral stops by the trial speech therapy. Video nasopharyngoscope confirmed that large velopharyngeal gaps can be decreased into tiny gaps or complete closure when compensatory articulations were corrected for some cases. Conclusion: Compensatory articulation errors must be corrected for the reliable interpretation of the nasalance scores that are obtained in children with velopharyngeal insufficiency, which would facilitate to make a better decision for further management of these patients.

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Analysis of Hydrodynamic Change around the Saemangeum Area Using a Particle Tracking Method (입자추적방법을 이용한 새만금 해역의 수리특성 변화 분석)

  • Suh, Seung-Won;Lee, Hwa-Young
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.23 no.6
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    • pp.442-450
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    • 2011
  • A three dimensional random walk particle tracking method is applied to the Saemangeum area in order to find stepwise environmental changes according to long term construction. Flow regime around Mangyeong, Dongjin and Geum river estuary changed greatly due to dike construction. It is distinctive that reduction of Byeonsan area's flow field and stagnant change in the northern part of the inner reservoir. Similar characteristics are found through the tidal excursion analysis. By analysis of the vertical mixing structures according to density stratification based on temperature and salinity variation, a salt wedge and very strong stratification arises in the inner part of the reservoir after final closure, while it has been well mixed or partially mixed estuary during construction. Shrinking of horizontal dispersion and vertical mixing capability may cause adverse effect on water quality not only inner part but also outer region of the Saemangeum reservoir.

TIMBER AGE ESTIMATION OF COMMERCIAL TIMBERLAND IN TENNESSEE, USA USING REMOTELY SENSED DATA

  • Lee, Jung-Bin;Kim, Sung-Hoon;Jayakumar, S.;Heo, Joon
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.449-451
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    • 2007
  • In the commercially managed timber lands, the information such as height, age, stand density, canopy closure and leaf area index need to be collected periodically. Stand volume is the most fundamental information in the valuation of timber, however, stand age information is the primary element of forest inventory and these two are highly correlated. Conventional method of collecting stand age information by field surveys such as ring count method is accurate; however, it is expensive, labor-intensive and time consuming. In the present study it was aimed to collect stand age information using modem techniques in a commercially managed timberland situated in Tennessee, USA. The Landsat Thematic Mapper (TM), Enhanced Thematic Mapper (ETM+) of three different periods, Shuttle Radar Topography Mission (SRTM), National elevation dataset (NED) and field inventory data were used. Normalized difference vegetation index (NDVI) and Tasselled Cap (TC) transformation techniques were applied on the TM and ETM+ data. The regression analysis was carried out to identify the correlation between stand age and NDVI, TC. In the present study about 2,469 datasets were analyzed. The $R^{2}$ value for stand age estimation was 0.713. The NDVI, TC2 and TC3 were found to produce accurate timber age information.

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Transcarotid Coil Embolization in a Yorkshire Terrier Puppy with Patent Ductus Arteriosus Using a JR Coronary Catheter and Free Push Deployment System (동맥관 개존증에 걸린 요크셔테러어종 자견에서 경동맥 경로와 JR Coronary Catheter/Free Push Deployment System을 이용한 색전코일을 이용한 치료증례)

  • Choi, Bum-Sul;Choi, Ran;Hyun, Chang-Baig
    • Journal of Veterinary Clinics
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    • v.28 no.2
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    • pp.240-243
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    • 2011
  • Several vascular accesses can be used for catheter guided coil embolization for occluding patent ductus arteriosus (PDA). Although trans-femoral approach is most commonly used in dogs, it is often unable to insert angiocatheter for inserting the coil delivery system, especially small puppies weighing less than 2 kg of body weight. Therefore this case study developed trans-carotid method for puppy using JR coronary catheter and free push delivery system. Using this new method, we successfully treated a puppy with PDA weighing 1.25 of body weight.

Crack effect on the elastic buckling behavior of axially and eccentrically loaded columns

  • Zhou, L.;Huang, Y.
    • Structural Engineering and Mechanics
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    • v.22 no.2
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    • pp.169-184
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    • 2006
  • A close form solution of the maximum deflection for cracked columns with rectangular cross-sections was developed and thus the elastic buckling behavior and ultimate bearing capacity were studied analytically. First, taking into account the effect of the crack in the potential energy of elastic systems, a trigonometric series solution for the elastic deflection equation of an arbitrary crack position was derived by use of the Rayleigh-Ritz energy method and an analytical expression of the maximum deflection was obtained. By comparison with the rotational spring model (Okamura et al. 1969) and the equivalent stiffness method (Sinha et al. 2002), the advantages of the present solution are that there are few assumed conditions and the effect of axial compression on crack closure was considered. Second, based on the above solutions, the equilibrium paths of the elastic buckling were analytically described for cracked columns subjected to both axial and eccentric compressive load. Finally, as examples, the influence of crack depth, load eccentricity and column slenderness on the elastic buckling behavior was investigated in the case of a rectangular column with a single-edge crack. The relationship of the load capacity of the column with respect to crack depth and eccentricity or slenderness was also illustrated. The analytical and numerical results from the examples show that there are three kinds of collapse mechanisms for the various states of cracking, eccentricity and slenderness. These are the bifurcation for axial compression, the limit point instability for the condition of the deeper crack and lighter eccentricity and the fracture for higher eccentricity. As a result, the conception of critical transition eccentricity $(e/h)_c$, from limit-point buckling to fracture failure, was proposed and the critical values of $(e/h)_c$ were numerically determined for various eccentricities, crack depths and slenderness.

The Effect of Activities of Daily Living(ADL) Training on the Visual Perception Capacity Performance Function of the Stroke (일상생활활동 훈련이 뇌졸중 환자의 시지각 기능에 미치는 효과)

  • Kim, Jiwon;Kim, Miyoung;Hwang, Bosun;Jang, Chel
    • Journal of The Korean Society of Integrative Medicine
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    • v.2 no.1
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    • pp.1-14
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    • 2014
  • Purpose : The aim of this study was to investigate Activities of Daily Living(ADL) function recovery of repeated measurement of stroke who received ADL training. Method : Twenty stroke patients were treated by ADL program therapy from May to June. All of in twenty stroke patients, 10 stroke patients take part in Occupational Therapy and 10 stroke patients take part in ADL training for 30 min five times a week during four weeks in M- hospital occupational Therapy treatment room, local in Changwon and Geoje. We used two assessment on is Motor Free Visual Perception Test-Third Edition(MVPT-3) for visual perception the other is Modified Barthel Index(MBI) for ADL. Result : First, Visual Short Term Memory(VSTM) score was changed statistical significance OT intervention group than compare with ADL training group(p<.05). Second, Visaul Closure(VC) score was changed statistical significance OT intervention group than compare with ADL training group(p<.05). Third, Spatial Orientation(SO) score was changed statistical significance OT intervention group than compare with ADL training group(p<.05). The fourth Motor Free Visual Perception Test-Third Edition(MVPT-3) score was changed statistical significance OT intervention group than compare with ADL training group(p<.05). The fifth Modified Barthel Index(MBI total) score was changed statistical significance OT intervention group than compare with ADL training group(p<.05). Conclusion : Therefore, ADL training can be on method the visual perception of stroke patients.

Effect of Surgical-Site, Multimodal Drug Injection on Pain and Stress Biomarkers in Patients Undergoing Plate Fixation for Clavicular Fractures

  • Yoo, Jae-Sung;Heo, Kang;Kwon, Soon-Min;Lee, Dong-Ho;Seo, Joong-Bae
    • Clinics in Orthopedic Surgery
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    • v.10 no.4
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    • pp.455-461
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    • 2018
  • Background: Surgical-site, multimodal drug injection has recently evolved to be a safe and useful method for multimodal pain management even in patients with musculoskeletal trauma. Methods: Fifty consecutive patients who underwent plating for mid-shaft and distal clavicular fractures were included in the study. To evaluate whether surgical-site injections (SIs) have pain management benefits, the patients were divided into two groups (SI and no-SI groups). The injection was administered between the deep and superficial tissues prior to wound closure. The mixture of anesthetics consisted of epinephrine hydrochloride (HCL), morphine sulfate, ropivacaine HCL, and normal saline. The visual analogue scale (VAS) pain scores were measured at 6-hour intervals until postoperative hour (POH) 72; stress biomarkers (dehydroepiandrosterone sulfate [DHEA-S], insulin, and fibrinogen) were measured preoperatively and at POH 24, 48, and 72. In patients who wanted further pain control or had a VAS pain score of 7 points until POH 72, 75 mg of intravenous tramadol was administered, and the intravenous tramadol requirements were also recorded. Other medications were not used for pain management. Results: The SI group showed significantly lower VAS pain scores until POH 24, except for POH 18. Tramadol requirement was significantly lower in the SI group until POH 24, except for POH 12 and 18. The mean DHEA-S level significantly decreased in the no-SI group ($74.2{\pm}47.0{\mu}g/dL$) at POH 72 compared to that in the SI group ($110.1{\pm}87.1{\mu}g/dL$; p = 0.046). There was no significant difference in the insulin and fibrinogen levels between the groups. The correlation values between all the biomarkers and VAS pain scores were not significantly different between the two groups (p > 0.05). Conclusions: After internal fixation of the clavicular fracture, the surgical-site, multimodal drug injection effectively relieved pain on the day of the surgery without any complications. Therefore, we believe that SI is a safe and effective method for pain management after internal fixation of a clavicular fracture.

Survey on water utilization status and saving mind for water demand management (물 수요관리를 위한 물 사용실태 및 물 절약 설문조사)

  • Lim, Bongsu;Kwon, Jeongin;Chu, Shaoxiong;Lee, Beumhee
    • Journal of Korean Society of Water and Wastewater
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    • v.32 no.6
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    • pp.507-515
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    • 2018
  • The results of the survey on water utilization status, the wasted water factor, the awareness, and the education and promotional activities of water saving in Daejeon City are as follows: The percentage of using tap valve with a closure was 66% when showering. 74% of water was used with closing the tap valve when washing faces with no water needed, it was still considered that there existed a wasting water. The most wasting reasons of water were found to be shower, bath, and laundry in order. In the awareness of practicing tap water saving, 9.1% of respondents acted actively, 53.4% of them were trying to practice it, and more than 63% had a positive awareness. In the contents of practicing saving water, locking water when soaping while showering, non-laundry of small quantity, and using cups when brushing teeth were top priorities. About 50% of the reasons for saving water was to practice purely saving water, when saving for economic help was excluded. The level of water saving awareness was not high when considering that the ratio of usage without water saving equipment and installation, and using method was relatively high when moving in. In order to make usage of water saving equipment more common, it was deemed necessary to provide information on the purchase of water saving equipment and to promote and educate the efficiency of saving of related products. More than about 90% of the respondents responded that water saving education or promotional activities had an effect of improving water saving awareness. The most effective method of education and promotional activities was found to be 40.4% by mass media activities, and 21.7% by promotions through mobile devices.

A Study on Disease Prediction of Paralichthys Olivaceus using Deep Learning Technique (딥러닝 기술을 이용한 넙치의 질병 예측 연구)

  • Son, Hyun Seung;Lim, Han Kyu;Choi, Han Suk
    • Smart Media Journal
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    • v.11 no.4
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    • pp.62-68
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    • 2022
  • To prevent the spread of disease in aquaculture, it is a need for a system to predict fish diseases while monitoring the water quality environment and the status of growing fish in real time. The existing research in predicting fish disease were image processing techniques. Recently, there have been more studies on disease prediction methods through deep learning techniques. This paper introduces the research results on how to predict diseases of Paralichthys Olivaceus with deep learning technology in aquaculture. The method enhances the performance of disease detection rates by including data augmentation and pre-processing in camera images collected from aquaculture. In this method, it is expected that early detection of disease fish will prevent fishery disasters such as mass closure of fish in aquaculture and reduce the damage of the spread of diseases to local aquaculture to prevent the decline in sales.