• 제목/요약/키워드: start time

검색결과 1,586건 처리시간 0.023초

송아지에 이식한 공기구동형 인공심장의 혈역학적 연구 (Hemodynamic study of Pneumatic Artificial Heart Implanted in Calves)

  • 박표원
    • Journal of Chest Surgery
    • /
    • 제23권3호
    • /
    • pp.438-451
    • /
    • 1990
  • Pneumatic total artificial heart[TAH] has been clinically applied for the purpose of permanent or temporary use followed by cardiac transplantation in the patients with end stage heart diseases. In spite of the good durability of the pneumatic TAH, thrombus formation, bleeding and infection resulted in death. The Tomasu heart, which is a type of pneumatic TAH, was used in this study. This model is a modified Jarvik heart and consists of atrial cuffs, outflow vascular grafts and thin-layer seamless diaphragm type of ventricles. Cardiac outputs of the left artificial heart were measured by Donovan`s mock circulation under variable conditions of driving parameters, and an experimental artificial heart implantation was performed in 4 calves to observe the changes of hemodynamic parameters in early postoperative period and hematologic and bio-chemical changes in a long-term survival case. In the mock circulation test, cardiac output of the heart was increased with the increase of the left atrial pressure and left driving pressure. Maximum cardiac output was obtained at the heart rate of 120 to 130/min and percent systole of 40 to 45Zo under the condition of a constant left driving pressure of 180mmHg and left atrial pressure of 10mmHg. During the first 24 hours of TAH pumping, driving pressure ranged from 178$\pm$5mmHg to 187$\pm$8mmHg for the left heart and from 58$\pm$6mmHg to 78$\pm$28mmHg for the right heart. The Mean arterial pressure significantly increased between 2 and 8 hours after the start of pumping. The survival time ranged from 27 hours to 46 days. The causes of death were respiratory failure in 2 cases, mechanical valve failure in one, and left ventricular outflow obstruction due to thrombus in a 46-day survival case. This study demonstrated that Tomasu artificial heart operated effectively during the first 24 hours of artificial heart pumping, but thrombus formation around the valve holding area was the main problem in long-term survival case.

  • PDF

Reaction-Bonded Al2O3 Ceramics Using Oxidation of Al Alloy Powder

  • Lee, Hyun-Kwuon
    • 한국재료학회지
    • /
    • 제24권5호
    • /
    • pp.236-242
    • /
    • 2014
  • Fabrication of reaction-bonded $Al_2O_3$ (RBAO) ceramics using Al-Zn-Mg alloy powder was studied in order to improve traditional RBAO ceramic processing using Al powder. The influence on reaction-bonding and microstructure, as well as on physical and mechanical properties, of the particulate characteristics of the $Al_2O_3$-Al alloy powder mixtures after milling, was revealed. Variation of the particulate characteristics of this $Al_2O_3$-Al alloy powder mixture with milling time was reported previously. To start, the $Al_2O_3$-Al alloy powder mixture was milled, reaction-bonded, post-sintered, and characterized. During reaction-bonding of the $Al_2O_3$-Al alloy powder mixture compacts, oxidation of the Al alloy took place in two stages, that is, there was solid- and liquid-state oxidation of the Al alloy. The solid-state oxidation exhibited strong dependence on the density of surface defects on the Al-alloy particles formed during milling. Higher milling efficiency resulted in less participation of the Al alloy in reaction-bonding. This was because of its consumption by chemical reactions during milling, and subsequent powder handling, and could be rather harmful in the case of over-milling. In contrast to very little dependence of oxidation of the Al alloy on its particle size after milling, the relative density, microstructure, and flexural strength were strongly dependent on particle size after milling (i.e., on milling efficiency). The relative density and 4-point flexural strength of the RBAO ceramics in this study were ~98% and ~365 MPa, respectively, after post-sintering at $1,600^{\circ}C$.

Dynamic study를 이용한 선조체에서의 18F-DOPA의 분포에 대한 평가 (Evaluation about Distribution of 18F-DOPA at Striatum by Using Dynamic Study)

  • 김재일;이홍재;김진의
    • 핵의학기술
    • /
    • 제19권1호
    • /
    • pp.67-71
    • /
    • 2015
  • Purpose At recently, we enter into the aging society and a age-related disease is increasing. Among that, prevalence of degenerative brain disease like Parkin's disease will be increased. So, many radiopharmaceuticals is developed to diagnosis early and to evaluate the performance of therapeutic drugs. Especially $^{18}F-DOPA$ which involved at dopamine synthesis and function of storage is widely used to the diagnosis of Parkinson's disease as well as brain tumors. in the study, we will evaluate the distribution pattern of $^{18}F-DOPA$ at the striatum by using dynamic study. Materials and Methods We used Biograph Truepoint(Siemens, Germany) as PET/CT scanner, injected a $^{18}F-DOPA$ ($600{\pm}30MBq$) to patient (4men, 6women. $67{\pm}11age$) who visited our hospital from June to September, started 95min dynamic study at same time. after finishing acquisition, we reconstructed PET data with 19 frame every 5 minutes, analysed a average counts at ROI's where set at both striatums, anterior putamen, posterior putamen Results Counts in the cerebellum as the background formed a plateau after 90 minutes from the highest out rapidly reduced to 15 minutes. Counts of anterior putamen and posterior gradually increased but formed a plateau after 60min. A count ratio of Striatum to cerebellum was continuously increased up to more than 95 minutes, A count ratios of an anterior putamen to posterior one formed a plateau after 85 minutes. Conclusion The dynamic acquisition can be possible to evaluate a distribution of the $^{18}F-DOPA$ in the striatum and the VOI analysis through a dynamic acquisition and a variety of patterns. Futhermore, to make a uniformed distribution and count ratio of striatum to cerebellum, a static acquisition will have to start 90minutes later after injection.

  • PDF

Aesthetic Characteristic Study on Sportswear Uniform - Concentrating on Sportswear Uniform Applying Ensign Image -

  • Kan, Ho-Sup;Kim, Tae-Hee
    • 패션비즈니스
    • /
    • 제12권3호
    • /
    • pp.99-115
    • /
    • 2008
  • International exchange gets active in nations with the increase of Internet use and heading toward digital age. Thus the communication conveying image of nations effectively plays an important role in an international society. Sports events are regarded as important international exchange events and good opportunities for public relations of one's own country and taken as tools of planting good images in other nations. This study surveyed the concept and history of uniform through the documents and previous studies in order to find the aesthetic characteristics of sportswear uniform applying the image of national ensign and investigates the origin and start time in Korea of selected 6 sports items. As a result of finding the expression way of ensign image and drawing the aesthetic characteristics by analyzing the use and variation of ensign colors, the use of colors other than ensign and reflection of ensign form in collected 60 sports uniforms, this study could draw the symbolical beauty, beauty of variation and beauty of brevity. First, symbolical beauty is the aesthetic characteristics expressing uniforms by using the pattern ensign symbolizes and ensign colors themselves or enlarging a part of ensign. Second, beauty of variation is the aesthetic characteristics creating geometrical new patterns in uniform through the distortion and exaggeration of ensign shape, or transforming the colors themselves of ensign. Third, beauty of brevity is the aesthetic characteristics using other colors only as decorative factor while applying the main colors of ensign to the most part of uniform, or unifying the uniforms with only one color of ensign. As a result of survey, the proportion of the symbolical beauty was highest in summer season and beauty of brevity and beauty of variation followed and the proportion of beauty of variation was highest and the symbolical beauty and beauty of brevity followed after that in winter season. This study found the way of expressing image of one's own country in sports uniform through this article, expecting the exact recognition on sports uniform and the diversity of sports uniform design in which the images of the nation are expressed more variously.

능동형 기울기 가중치 제약에 기반한 환경소리 인식시스템용 DTW 알고리듬 (Active Slope Weighted-Constraints Based DTW Algorithm for Environmental Sound Recognition System)

  • 정영진;이윤정;김필운;김명남
    • 한국멀티미디어학회논문지
    • /
    • 제11권4호
    • /
    • pp.471-480
    • /
    • 2008
  • 농자들은 청각장애를 가지고 있기 때문에 알람, 도어 벨, 싸이렌, 경적, 전화 벨 등과 같은 유용한 소리정보를 인식할 수 없다. 이러한 문제를 해결하기 위해서는 주요한 환경소리 인식방법을 탑재한 휴대형 청각보조 장구가 요구되어진다. 본 논문에서는 환경소리 인식시스템에 적용할 수 있는 능동형 기울기 가중치제약 방식의 새로운 동적 시간정합 알고리듬을 제안하였다. 환경소리 인식방법은 크게 세 단계로 구성된다. 첫 번째 단계에서는 소리의 주파수 성분과 크기를 이용하여 시작점과 끝점을 추출한다. 두 번째 단계에서는 추출된 구간에 대하여 특징을 추출하며 세 번째 단계에서는 추출된 특징들을 분류한다. 실험 결과 제안한 방법의 인식률이 거의 90%가 되었다. 그리고 기존의 동적 시간정합 알고리듬과 비교하였을 때 인식율에 있어서 약 20%정도의 개선이 있었다. 따라서 제안된 방법을 사용하여 농자가 환경소리를 인식할 수 있는 휴대형 청각 보조 장구가 개발된다면 그들의 생활에 편리함을 줄 수 있을 것으로 판단된다.

  • PDF

워크플로우 임계 경로에 관한 분석 (Analyses on the Workflow Critical Path)

  • 손진현;장덕호;김명호
    • 한국정보과학회논문지:데이타베이스
    • /
    • 제28권4호
    • /
    • pp.677-687
    • /
    • 2001
  • 임계 경로는 방향성 비순환 그래프 분야를 포함하여 많은 컴퓨터 공학 분야들에서 널리 활용되어 왔다. 워크플로우에서 임계 경로는 여러 개의 예상 수행 경로들 중에서 가장 긴 평균 수행 시간을 가지는 하나의 경로로 정의되며, 이 개념은 워크플로우 옹용 영역들에서 유용하게 사용될 수 있다. 일반적 으로 특정 워크플로우에 대해 동시에 수행되는 워크플로우 인스턴스들이 여러 개가 존재하므로 워크플로 우 환경에 적합한 새로운 임계 경로 결정 방법의 개발이 필요하다. 본 논문에서 우리는 먼저 워크플로우 특징들을 쉽게 분석할 수 있는 워크플로우 대기 행렬 네트워크 모델에 대해서 언급한다. 그리고, 이 모델을 기반으로 워크플로우 임계 경로를 결정하는 방법을 제안한다. 추가적으로. 워크플로우 임계 경로 개념을 효율적으로 활용할 수 있는 워크플로우 응응 영역들을 몇가지 소개한다.

  • PDF

액체로켓엔진 연소기 산화제 선공급 Cyclogram에 의한 점화특성 (Ignition Characteristics of Combustion Chamber with $LO_X$ Lead Cyclogram for Liquid Rocket Engine)

  • 한영민;김종규;이광진;임병직;안규복;김문기;서성현;최환석
    • 한국추진공학회:학술대회논문집
    • /
    • 한국추진공학회 2008년도 제31회 추계학술대회논문집
    • /
    • pp.137-142
    • /
    • 2008
  • 액체로켓엔진 재생냉각 연소기에서 산화제 선공급 cyclogram시의 점화 특성에 대해 기술하였다. 연소기의 연소압력은 60 bar, 추진제 유량은 약 89 kg/s 그리고 노즐 팽창비는 12이다. 산화제 선공급 cyclogram을 위해 수행한 연소기로의 연료 및 산화제 수류시험, 산화제 선공급에 따른 점화기 작동성 확인을 위한 점화시험, 연소기의 주 점화 및 연소 확인을 위한 저압 연소시험 그리고 설계점에서 연소기 작동성/연소 안정성 및 연소성능/재생냉각 성능 확인을 위한 연소시험 등에 대해 기술하였다. 산화제 선공급 점화 및 연소시험은 성공적으로 이루어졌으며 연소기에 대한 안정적인 점화 cyclogram을 개발하였다.

  • PDF

사암침으로 호전된 동공산대를 동반한 동안신경마비 1례 (Case Report of Oculomotor Nerve Palsy with Mydriasis Improved by Sa-Am Acupuncture)

  • 이주현;박민철;홍지은;박지원;조은희
    • 동의생리병리학회지
    • /
    • 제35권2호
    • /
    • pp.81-85
    • /
    • 2021
  • This study aims to report a case of oculomotor nerve palsy with mydriasis improved by Sa-Am acupuncture (大腸正格). The patient visited our clinic due to Right oculomotor nerve palsy with symptoms such as periocular pain, diplopia, vertigo, ptosis, eye adduction disorder, and mydriasis on November 11th, 2019. For the treatment, Sa-Am acupuncture (大腸正格) which used to give a significant effect on eye diseases and headaches and to remove toxins from the body was performed every time the patient visited the clinic. About a month after the treatment, ptosis disappeared, and eye adduction disorder also changed from -2 to 2 points, showing a significant improvement. Subjective symptoms such as vertigo, diplopia, and eye pain also significantly decreased from 13 to 4 points. At the second month of treatment, the eye adduction disorder improved to a normal level, and subjective ocular discomforts disappeared. The pupil size decreased from 5 mm to 2.5 mm. After 3-4 months from the start of treatment, most of the symptoms including the light reflex returned to normal. After a total of 32 acupunctures treatment, subjective symptoms such as periocular pain, diplopia and vertigo, as well as ptosis and eye adduction disorder disappeared, and the pupil size, including the light reflex, also improved to the normal level.

생애과정에 걸친 노숙 위험요인에 관한 탐색적 연구 : 성장기 불행한 경험을 중심으로 (Homeless Risk Factors through the life courses : Focusing on the childhood adverse experiences)

  • 김소영
    • 사회복지연구
    • /
    • 제48권1호
    • /
    • pp.143-171
    • /
    • 2017
  • 본 연구는 노숙인의 성장기와 노숙 이전의 노숙 위험요인 경험을 확인하면서, 특히 성장기의 불행한 경험이 성인기의 노숙 발생에 미치는 영향을 살펴보고자 하였다. 기존의 노숙에 대한 개인적 원인에 관한 연구들은 노숙 전후의 알코올 문제, 정신건강 문제, 약물중독, 노숙인의 비행과 일탈 등에 주로 초점을 맞추어 온 반면, 본 연구는 노숙의 개인적 요인을 더욱 세분화하면서 그 시점을 노숙인의 성장기까지 앞당겨 이들이 경험한 위험요인의 중복, 상호작용, 노숙에 미친 영향 등을 파악하고자 하였다. 60명의 노숙인 생애사 자료에서 추출한 경험을 분석해 본 결과, 노숙인들은 이미 성장기부터 중첩된 많은 위험요인을 경험하였고, 이것은 성인기로 오면서 이들 위험요인간의 상호작용을 통해 증폭되는 경향을 보이기도 하였다. 또한 위험요인 경험 정도가 높은 그룹과 낮은 그룹을 비교해 보았을 때, 노숙에 이르게 된 원인의 차이도 발견할 수 있었다. 이러한 연구결과를 바탕으로 노숙의 개인적 원인이 일찍부터 시작된 불가항력적인 불행과 배제, 피해의 경험으로부터 시작된 면도 존재한다는 점을 강조하면서, 결과적 노숙의 예방은 고위험 아동청소년에 대한 적극적 개입과 위험요인의 중첩을 방지하는 전략이 수반되어야 함을 지적하였다.

한국인과 일본인의 죽음의식 비교연구 (The Comparative Study of the View about the Death of Korean and Japanese)

  • 정수현
    • 비교문화연구
    • /
    • 제30권
    • /
    • pp.73-95
    • /
    • 2013
  • The purpose of this paper look at the basis of the cultural differences of Korea and Japan by comparing the view about the death. Firstly, in terms of language to express the death, Korea can be summarized 'doragada (go back) Japan can be summarized sayonara(goodbye). Koreans' view about the death is that life and death are not separated and death is the start of another life not the end of existence through 'doragada' Japanese accept death as the order of the universe and the order of nature with resignation. At this time resignation means that Japanese accept the sad feeling to sublimate aesthetically while mourning the death Secondly The view about the death of Sunbee in the Joseon era and Japanese Samurai who were the traditional ideal figures is compared. The Sunbee dies from a justification and the Samurai die from the honor on the other hand. Unconditionally, the sunbee was not loyal to an individual but they thought significantly of the fidelity about the joint value. Unlike this, Japanese Samurai laid stress on the loyalty toward their lord and sacrifice. They selected the death conclusively when this fidelity was suspected. Thirdly the view about the death of Korea and Japan is summarized to the aesthetics of the survival and the aesthetics of the death. Korean saw the death negatively and regard exceedingly the extension of life, they preceded to survive in all kinds of difficulties. On the contrary, Japanese see it positively. They beautified the death and sublimated with the aesthetics. they pursue the nature of the life through the death. Finally, the basic difference of the korean and Japanese culture originate from the view about the death that is, the difference of the values about the life and death.