• 제목/요약/키워드: Abnormal change

검색결과 727건 처리시간 0.029초

Effect of Debinding Conditions on the Microstructure of Sintered Pb(Mg1/3Nb2/3)O3-PbTiO3

  • Yun Jung-Yeul;Jeon Jae-Ho;L.Kang Suk-Joong
    • 한국분말재료학회지
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    • 제12권4호
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    • pp.261-265
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    • 2005
  • In order to fabricate complex-shaped polycrystalline ceramics by sintering, organic binders are usually pre-mixed with ceramic powders to enhance the formability during the shape forming process. These organic binders, however, must be eliminated before sintering so as to eliminate the possibilities of poor densification and unusual grain growth during sintering. The present work studies the effect of binder addition on grain growth behavior during sintering of $92(70Pb(Mg_{1/3}Nb_{2/3})O_3-30PbTiO_3))$-8PbO(mol%) piezoelectric ceramics. The microstructures of the sintered samples were examined for various heating profiles and debinding schedules of the binder removal process. Addition of Polyvinyl butyral(PVB) binder promoted abnormal grain growth especially in incompletely debinded regions. Residual carbon appears to change the grain shape from comer-rounded to faceted and enhance abnormal grain growth.

이상조건하에서 가정용 연료전지 시스템의 성능 및 안전성 평가에 관한 연구 (A Study on the Performance and Safety Evaluation for Residential Fuel Cell System under the Abnormal Condition)

  • 이정운;서원석;김영규
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2008년도 추계학술대회 논문집
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    • pp.10-13
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    • 2008
  • Fuel cell systems have witnessed remarkable development in recent years as they offer a clean and efficient alternative for power generation. Testing was conducted to determine the safety performance of a residential fuel cell system when subjected to abnormal operation condition, especially for voltage sag and fuel cut. In case of voltage sag to 198V, its arriving time at rated power had shown a slight lag but there wasn't any noticeable change when operating it between rated voltage(220V) and 10% voltage sag(198V). In case of fuel cut, it also showed stable shut-down characteristics. The test results are being used to develop a new safety evaluation for residential fuel cell system.

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전반적 발달장애 아동의 식습관 양상 (The Features of Eating Habit in Pervasive Development Disorder Children)

  • 박금순;정철호
    • 한국식품조리과학회지
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    • 제10권1호
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    • pp.13-17
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    • 1994
  • The purpose of this study was to show the abnormal eating habit in pervasive development disorder (PDD) children. The authors studied retrospectively the features of eating habit in 60 PDD children diagnosed by DSM-III-R who made their first visity to Department of Psychiatry, Dongsan Medical Center Keimyung University, from January 1990 to December 1990. The results were as follows;1. The average was 3 years, onset age of illness was before 3 years of all patients, and the ratio between male and female was 5,7:1, and ratio between autistic disorder and PDDNOS was 4:1. 2. Twenty four of 60 PDD children had one or more abnormal eating habit(autistic disorder; 43.8%, PDDNOS; 25%), and more prevalent to male(43.1%,) than female(22.2%). 3. Milk, biscuit, meat and fluids were the favorate foods, the unfavorate foods were vegetable, rice, frutis. 4. Patients of abnormal eating habit were more symptoms of DSM-III-R on 'lack of awareness', 'preoccupation with parts of objects','distress over change'and 'insistence on routine' than others.

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지하투과레이더 신호의 보정을 통한 도심지 내 지반 이상구간의 검측 (Detection of Abnormal Area of Ground in Urban Area by Rectification of Ground Penetrating Radar Signal)

  • 강성훈;이종섭;이성진;이진욱;홍원택
    • 지질공학
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    • 제27권3호
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    • pp.217-231
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    • 2017
  • 도심지 내 지반침하는 공동의 생성 및 체적함수비의 급격한 변화에 의하여 발생할 수 있는 것으로 알려져 있다. 본 연구에서는 보정 기법이 적용된 지하투과레이더 신호를 이용하여 도심지 내 공동 및 체적함수비의 급격한 변화가 발생한 지반 이상 구간을 검측하고자 하였다. 지반 이상구간에 대한 신호 획득을 위하여 구형의 공동을 모사한 모형지반을 대상으로 지하투과레이더 탐사를 수행하였다. 필터링 기법을 적용하여 설정한 대역폭을 통과하는 신호만을 측정하였으며, 이후 이득 함수, 타임 제로, 배경 제거, 디콘볼루션, 영상 이득 기법을 적용하고 각 기법의 적용에 따른 신호의 변화양상을 비교하였다. 신호처리 및 영상화 기법을 적용한 결과, 공동 발생 구간의 전기적 임피던스 대소관계에 부합하는 위상이 나타났다. 지하투과레이더 측정 신호를 이용하여 산정한 상대 유전율과 모형지반의 체적함수비를 이용하여 예측한 상대 유전율을 비교한 결과, 각 방법으로 도출된 상대 유전율은 서로 유사한 값을 보였다. 이를 통하여 도심지와 같이 매설물의 깊이가 알려져 있는 경우, 보정된 지하투과 레이더 신호를 통하여 체적함수비의 급격한 변화 구간 또한 검측할 수 있을 것이라 판단된다. 본 연구에서 제시된 신호의 보정 기법과 상대 유전율의 산정은 도심지 내 공동 발생 구간 및 체적함수비의 급격한 변화 구간과 같은 이상구간 검측에 활용될 수 있을 것으로 판단된다.

갑상선 수술 후 발생하는 음성장애의 치료 (Voice Care for the Post-Thyroidectomy Dysphonia)

  • 정은재
    • 대한후두음성언어의학회지
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    • 제27권1호
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    • pp.14-17
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    • 2016
  • Hoarseness is a postoperative complication of thyroidectomy, mostly due to damage to the recurrent laryngeal nerve (RLN). Hoarseness may also be brought about via vocal cord dysfunction (VCD) due to injury of the vocal cords from manipulations during anesthesia, as well as from psychogenic disorders and respiratory and upper-GI related infections. The clinician or surgeon should 1) document assessment of the patient's voice once a decision has been made to proceed with thyroid surgery ; 2) examine vocal fold mobility, or refer the patient to a clinician who can examine vocal fold mobility 3) examine vocal fold mobility, or refer the patient to a clinician who can examine vocal fold mobility, once a decision has been made to proceed with thyroid surgery 4) educate the patient about the potential impact of thyroid surgery on voice once a decision has been made to proceed with thyroid surgery ; 5) inform the anesthesiologist of the results of abnormal preoperative laryngeal assessment in patients who have had laryngoscopy prior to thyroid surgery ; 6) take steps to preserve the external branch of the surperior laryngeal nerve(s) when performing thyroid surgery ; 7) document whether there has been a change in voice between 2 weeks and 2 months following thyroid surgery ; 8) examine vocal fold mobility or refer the patient for examination of vocal fold mobility in patients with a change in voice following thyroid surgery ; 9) refer a patient to an otolaryngologist when abnormal vocal fold mobility is identified after thyroid surgery ; 10) counsel patients with voice change or abnormal vocal fold mobility after thyroid surgery on options for voice rehabilitation.

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후처리과정을 통한 CTD 관측 자료 품질 개선에 대하여 (The Improvement of CTD Data through Post Processing)

  • 최아라;박영규;민홍식;김경홍
    • Ocean and Polar Research
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    • 제31권4호
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    • pp.339-347
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    • 2009
  • It is possible to obtain accurate temperature and salinity profiles of the oceans using a SBE 911plus CTD and accompanying data conversion packages. To obtain highly accurate results, CTD data needs to be carefully processed in addition to proper and regular maintenance of the CTD itself. Since the manufacturer of the CTD provides tools that are necessary for post processing, it is possible to conduct proper processing without too much effort. Some users, however, are not familiar with all of the processes and inadvertently ignore some of these processes at the expense of data quality. To draw attention to these and other similar issues, we show how it is possible to improve data quality by utilizing a few extra processes to the standard or default data process procedures with CTD data obtained from the equatorial Eastern Pacific between 2001 and 2005, and 2007. One easy step that is often ignored in the standard data process procedure is "wild edit", which removes abnormal values from the raw data. If those abnormal values are not removed, the abnormality could spread vertically during subsequent processes and produce abnormal salinity in a range much wider than that of the raw data. To remove spikes in salinity profiles the "align CTD" procedure must be carried out not with the default values included in the data processing software but with a proper time constant. Only when "cell thermal mass" correction is conducted with optimal parameters, we can reduce the difference between upcast and downcast, and obtain results that can satisfy the nominal accuracy of the CTD.

과다산소조건이 가토의 심전도상에 미치는 영향에 관한 연구 (A Study on The Effect of Hyperoxia on EKG Findings of Rabbits)

  • 이수진;송재철;박항배
    • Journal of Preventive Medicine and Public Health
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    • 제25권1호
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    • pp.34-43
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    • 1992
  • To investigate the effect of hyperoxia on EKG findings and to evaluate the applicability of EKG as noninvasive monitoring index of oxygen toxicity, 38 rabbits were continuously exposed to 6 different conditions-3 hyperbaric oxygenations (HBO-2.5, 3.5 and 5ATA, 100% $O_2$), normobaric oxygenation (NBO,100% $O_2$), hyperbaric aeration (HBA-5ATA, 21% $O_2$) and normobaric aeration (NBA, 21% $O_2$)-for 120 minutes and their EKG and time to dyspnea and convulsion were recorded. Dyspnea and death were observed in exposure conditions of HBO-3.5 and HBO-5 (Positive rate of dyspnea 10%, 100%, death : 10%, 25%, respectively) only, and convulsion in 4 oxygenation groups (NBO;20%, HBO-2.5;20%, HBO-3.5;20%, HBO-5;88%). Abnormal EKG findings included arrhythmia and ST-T changes and the incidences was increasing with doses(partial pressure of oxygen). In addition to EKG change, findings observed during exposure were dyspnea and convulsion in the order of appearance and when non specific ST-T change was accepted as positive(abnormal) finding, the frequency of abnormal EKG was statistically significant(p<0.01), but when it was excluded from positive results, the frequency of EKG change was not significant(p>0.05). These results suggest that the effect of hyperoxia on heart is myocardial ischemia and arrhythmia, that oxygenation more than 3.5ATA causes myocardial damage in 120 minutes exposure, and that EKG is valuable as monitoring index of oxygen toxicity.

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드릴 가공된 구멍의 상태 검출에 관한 연구 (A Study on the Detection of the Drilled Hole State In Drilling)

  • 신형곤;김태영
    • 한국공작기계학회논문집
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    • 제12권3호
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    • pp.8-16
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    • 2003
  • Monitoring of the drill wear :md hole quality change is conducted during the drilling process. Cutting force measured by tool dynamometer is a evident feature estimating abnormal state of drilling. One major difficulty in using tool dynamometer is that the work-piece must be mounted on the dynamometer, and thus the machining process is disturbed and discontinuous. Acoustic transducer do not disturb the normal machining process and provide a relatively easy way to monitor a machining process for industrial application. for this advantage, AE signal is used to estimate the abnormal fate. In this study vision system is used to detect flank wear tendency and hole quality, there are many formal factors in hole quality decision circularity, cylindricity, straightness, and so of but these are difficult to measure in on-line monitoring. The movement of hole center and increasement of hole diameter is presented to determine hole quality. As the results of this experiment AE RMS signal and measurements by vision system are shorn the similar tendency as abnormal state of drilling.

소변의 생성, 구성성분, 색깔, 그리고 이상소견 (Overview of the Formation, Components, Color, and Abnormal Findings of Urine)

  • 박세진;신재일
    • Childhood Kidney Diseases
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    • 제17권2호
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    • pp.29-34
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    • 2013
  • Urine production is vital for the removal of certain waste products produced by metabolism in the body and for the maintenance of homeostasis in the body. The kidneys produce urine by the following three precisely regulated processes: filtration, reabsorption, and secretion. Urine is composed of water, certain electrolytes, and various waste products that are filtered out of the blood through the glomeruli. The physical features of urine are evaluated carefully to detect any abnormal findings that may indicate underlying diseases in the genitourinary system. A change in urine color may indicate an underlying pathological condition, although many of the causes of abnormal urine color are benign effects of medications and foods. A characteristic and specific odor may be the result of a metabolic disease rather than a concentrated specimen or a simple urinary tract infection. Although transient changes in urine output and nocturia are usually benign conditions, persistent abnormal findings require further workup, with a thorough medical history taking. This article presents many of the conditions that physicians may encounter and will help them in the diagnosis and in establishing a treatment plan.

컴퓨터 알고리즘에 의한 표면온도와 레이저 열전도에 관한 연구 (Study on the Surface Temperature and Laser Heat Conduction by the Computer Algorithm)

  • 이영욱
    • 정보학연구
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    • 제9권3호
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    • pp.67-75
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    • 2006
  • This study deals with the computing the temperature change of surface to the increment of time and diffusivity, the heat flux during irradiation of laser. In addition, the computer algorithm for computing the penetration change of the corresponding surface irradiated is developed. The result of this study shows the possibility to treatment of cancer, abnormal cell and biological tissue during irradiation of laser.

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