• 제목/요약/키워드: beating

검색결과 364건 처리시간 0.026초

Robot-Assisted Repair of Atrial Septal Defect: A Comparison of Beating and Non-Beating Heart Surgery

  • Yun, Taeyoung;Kim, Hakju;Sohn, Bongyeon;Chang, Hyoung Woo;Lim, Cheong;Park, Kay-Hyun
    • Journal of Chest Surgery
    • /
    • 제55권1호
    • /
    • pp.55-60
    • /
    • 2022
  • Background: Robot-assisted repair of atrial septal defect (ASD) can be performed under either beating-heart or non-beating-heart conditions. However, the risk of cerebral air embolism (i.e., stroke) is a concern in the beating-heart approach. This study aimed to compare the outcomes of beating- and non-beating-heart approaches in robot-assisted ASD repair. Methods: From 2010 to 2019, a total of 45 patients (mean age, 43.4±14.6 years; range, 19-79 years) underwent ASD repair using the da Vinci robotic surgical system. Twenty-seven of these cases were performed on a beating heart (beating-heart group, n=27) and the other cases were performed on an arrested or fibrillating heart (non-beating-heart group, n=18). Cardiopulmonary bypass (CPB) was achieved via cannulation of the femoral vessels and the right internal jugular vein in all patients. Results: Complete ASD closure was verified using intraoperative transesophageal echocardiography in all patients. Conversion to open surgery was not performed in any cases, and there were no major complications. All patients recovered from anesthesia without any immediate postoperative neurologic symptoms. In a subgroup analysis of isolated ASD patch repair (beating-heart group: n=22 vs. non-beating-heart group: n=5), the operation time and CPB time were shorter in the beating-heart group (234±38 vs. 253±29 minutes, p=0.133 and 113±28 vs. 143±29 minutes, p=0.034, respectively). Conclusion: Robot-assisted ASD repair can be safely performed with the beating-heart approach. No additional risk in terms of cerebral embolism was found in the beating-heart group.

종이의 특성에 영향하는 펄프 섬유특성의 정량적 해석(I) (Quantitative Analysis of Pulp Fiber Characteristics that Affect Paper Properties(I))

  • 이강진;박중문
    • 펄프종이기술
    • /
    • 제30권2호
    • /
    • pp.47-54
    • /
    • 1998
  • Refining is one of the most important processes of fiber treatment that provides optical and physical properties of final paper products. The evaluation method of refining progress is usually freeness (CSF) or wetness (SR) test because of its rapidity and convenience. However, there are some deficiencies in using freeness or wetness test to evaluate pulp fibers accurately because its results are more influenced by fines contents than extent of fibers treatment. The objective of this study is to show the deficiency of wetness in evaluating the refining process. For this, beating is done by varying the beating load. Handsheets are made after beating until 25 and $32^{\circ}C$ SR, and then paper properties are measured. Refined fibers are analyzed by fiber length, fines contents, curl, kink, WRV, and zero-span tensile strength. The results show that longer beating time is required to reach the same wetness at lower beating load. There are differences in the average fiber length, distribution curve of fiber length, fines contents, curl, kink, WRV of long fiber fraction, drainage time, and zero-span tensile strength of rewetted sample at different beating load. At the low beating load in the same wetness, apparent density, breaking length, burst strength, and tear strength are higher, while opacity and air permeability are lower than those of the high beating load. Using Page s equation, which shows the relationship among tensile strength, intrinsic fiber strength, and interfiber bonding strength, interfiber bonding strength is calculated and analyzed to explain final paper properties. At $25^{\circ}C$ SR, interfiber bonding strength is only slightly higher at 2.5kgf beating load, while the intrinsic fiber strength is substantially higher. At $32^{\circ}C$ SR, intrinsic fiber strength is a little bit higher at 2.5kgf beating load, and interfiber bonding strength is remarkably higher than those of 5.6kgf beating load. These results can be used to explain the different properties of the final paper at selected beating loads.

  • PDF

사이징과 고해에 따른 종이의 열화기구(제2보) -고해의 영향- (Deterioration Mechanism of Paper According to Sizing and Beating (II) -Influences of Beating-)

  • 김봉용
    • 펄프종이기술
    • /
    • 제31권2호
    • /
    • pp.58-63
    • /
    • 1999
  • Three kinds of papers were prepared from different beating degree of pulps. Physical and optical properties were examined to elucidate the deterioration mechanism of paper according to beating degrees. Changes of double folds, elongation, water retention value, DP, K/S value and visible, UV region light absorption spectra of those papers treated by UV light were studied. Double folds and brightness were decreased more rapidly by UV treatment with increasing of beating degree. The light absorption rates of pulps in visible and UV region were also increased with change of beating level. The formation of new hydrogen bonds and higher light absorption rate of pulps according to beating induced to absorb and interact with much UV light. These phenomena maybe brought about to accelerate paper deteriortion by UV treatment both optical and physical properties.

  • PDF

유과 조리법의 표준화에 관한 연구(I) -찹쌀의 수침기간과 꽈리치기 횟수를 중심으로- (Studies on Optimum Conditions for Experimental Procedure of Yukwa (I) -On the soaking time of glutuous rice and the number of beating-)

  • 전형주;손경희;박현경
    • 한국식생활문화학회지
    • /
    • 제10권2호
    • /
    • pp.75-81
    • /
    • 1995
  • This study was attempted to standard Yukwa recipies by proposing optimal conditions for soaking time and the number of beating. Soaking time and the number of beating had effects on the number of peak, implying that 15 days of soaking time at $15^{\circ}C$ and 160 times of beating would be required. In Yukwa's microstructural image, the better groups were over 15 days of soaking time and as number of beating increased, the appearance improved. The longer soaking time, the better tenderness and expansion volume. The number of beating had significant effects on all sensory evaluation except volume. Response surface model showed that the optimal condition would be at least 15 days of soaking and 319 times of beating.

  • PDF

고속 래피어 직기용 바듸침 캠의 최적설계 (Optimum Design of Beating Cam for High Speed Rapier Loom)

  • 김종수;김대원
    • 연구논문집
    • /
    • 통권28호
    • /
    • pp.89-100
    • /
    • 1998
  • This paper deals with the design and analysis of a beating cam. The beating device of a high speed rapier loom, weaving fabric by completion of warp-weft patterns, is driven by double cam type on the same axis. As the double cam, coupled with two cams, performs the mutual conjugate motion, the double cam must be very preciously designed for smooth. For the shape design of a double cam, an instant velocity center method is proposed. This method can determine the cam profile from the contact conditions of the cam and roller follower and the velocity relationships at the instant velocity center. And the practical applicability was verified by developing “DISKCAM of a CAD program. As the results in this paper, the shapes of two cams, which are in the conjugate motion, are designed by instant velocity center method. We applied 8-order polynominals for the beating as displace¬ment curves for shape determination of double cams. The data of displacement, velocity, and acceleration of beating cam can be used adjust in accurate operation and to develope an advanced beating device.

  • PDF

면섬유 고해 시 TiO2 혼합처리가 종이물성에 미치는 영향 (Effects of Beating of Cotton Linter Pulps with Titanium Dioxide on Paper Properties)

  • 길정하;신현식;이진호;박종문
    • 펄프종이기술
    • /
    • 제45권2호
    • /
    • pp.27-32
    • /
    • 2013
  • To improve the physical properties, such as swelling and flexibility, of the cotton fiber, sodium hydroxide or cellulase was used for pretreatment before the beating process. Titanium dioxide was blended during beating process to improve the fibrillation of cotton fibers and even distribution of fillers to cotton fibers. Blending with titanium dioxide during beating process, led to improve the tensile strength and beating degree This treatment also improved the opacity, resulted by well dispersed titanium dioxide during blending. By the blending of titanium dioxide during beating process, similar impact of cotton fiber with cellulase or sodium hydroxide pretreatment was achieved. To improve the tensile strength and opacity of cotton paper simultaneously, titanium dioxide blending in during beating process was found as effective treatment.

경주지역 평기와의 타날형태 변화에 대한 검토 -단판·중판·인장 그리고 장판으로- (A Study on changes in Hitting-pressing forms of flat plate in Gyeongju area -Short beating, Medium beating plate, long beating plate and Stamped-roof tile-)

  • 차순철
    • 헤리티지:역사와 과학
    • /
    • 제40권
    • /
    • pp.73-104
    • /
    • 2007
  • 신라왕경지역에 대한 발굴조사에서 출토된 평기와와 전 중에서 비교적 초기 기와가 출토된 것 으로 인정되고 있는 유적을 중심으로, 출토사례와 평기와 제작방법-단판(短板), 중판(中板), 장판(長板) 그리고 인장와(印章瓦)-에 대한 비교작업을 통해서 개개 유물이 출현한 시기에 대한 초보적인 접근을 시도하였다. 그 결과 경주지역에서 기와가 제작된 시기에 대해서는 앞으로 많은 자료의 출현을 기대해야 할 필요가 있다. 기와의 사용은 무와통(無瓦桶) 혹은 와통으로 제작된 단판 기와가 초기에 제작되다가, 무와통식 기와가 소멸하게 되는데, 이는 결국 와통을 이용한 기와제작법의 효율성에 기인한 것으로 판단된다. 단판 기와 역시 중판 타날판으로 제작된 기와와 비교해 볼 때, 작업능률면에서 뒤떨어지지만 매우 정성을 들여서 제작을 하였다. 이러한 작업공정은 단순히 작업능률만으로 설명하기 어려운 부분으로, 이들 단판 기와의 제작은 궁성 혹은 관청 등으로 납품되는 기와에 한정 되었을 기능성을 보여 준다. 따라서 단판 기와는 일정한 목적을 가지고 제작되었을 가능성이 제기된다. 중판 기와는 통쪽(模骨) 혹은 원통 와통(圓筒瓦通)에 의해 제작된 기와로 신라가 백제와 고구려를 병합한 이후로는 전국적으로 확산되게 된다. 고구려나 백제와 달리 신라 고유의 제와술이 반영된 기와로 대량생산에 적합한 제작법으로 전국적으로 급속하게 보급되게 되면서, 고구려 백제계 제와 술은 점차 소멸하게 된다. 장판 기와는 경주지 역에서는 거의 확인되지 않지만, "사천왕사"명 평기와와 삼랑사3길 유적에서 출토된 어골문 평기와 등이 알려져 있다. 경주 외곽에서는 장판 기와가 8세기 후반에서 9세기 초에 등장하는 것으로 보고되고 있고, 타날판에 새겨진 문양을 보면 선조문, 어골문, 사격자문등과 다소 복잡해진 기하학문과 각종 문자(연호, 지명 등)가 확인된다. 현재까지 경주지역에서 확인된 통일신라의 장판 기와의 존재에 대해서는 여러 가지 이견이 있으므로, 이 문제를 풀기 위해서는 사천왕사와 같이 창건연대가 분명한 유적에 대한 발굴조시를 통해서 확실한 층위적 공반관계에 기초한 기와연구가 이루어져야 할 것이다. 경주지역에서 인장와가 사용되는 시기는 무와통작법(無瓦桶作法)이나 단판 기와보다 늦으며, 백제지역의 경우 오부(五部)나 간지 (干支) 등이 확인되는데 비하여, 신라지역에서는 부호나 기호가 많이 보이고 있다. 이러한 차이는 인장와를 제작하던 공인집단의 성격차이로 보이며, 신라에서 인장와가 확인되는 시점은 679년을 기준으로 그 이후로 추정된다. 또한 인장와 및 인장전에 표기된 내용이 문자가 아니라 기호인 점은 백제지역에서 기존에 시용하던 방식이 변화되었음을 알려주며 그러한 계기는 결국 신라의 병합에 의한 제작환경의 변화로 추정된다. 그리고 인장와는 경주지역에서 일시적으로 사용되다가 소멸되는데, 그러한 원인은 결국 원통 와통과 중판 타날로 제작되던 <신라기와>가 전국적으로 보급되면서, 고구려나 백제의 제와기술이 도태되는데서 찾을 수 있다. 결국 신라에 의한 삼국의 병합은 국가별로 각각 특징이 있던 제와기술을 신라의 것으로 통일시키는 과정에서 귀착된 것이다.

팬 작동에 따른 비팅성 아이들 진동 평가 (Evaluation of idle vibration beated by cooling fan imbalance)

  • 박진한;안세진;정의봉
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2014년도 추계학술대회 논문집
    • /
    • pp.247-249
    • /
    • 2014
  • The beating phenomenon occurs because of various causes, when idle vibration was happened. In this study, the beating phenomenon was divided into several parameters and controlled by the parameter. It was hypothesized that the beating parameter is related to discomfort of idle vibration. The three-down one-up method was performed for evaluating discomfort of controlled vibrations, which is widely used in the field of psychophysics. As a result in pilot test, a subject responds beating vibration more discomfort than normal idle vibration. In the future, the study will be implemented to know how much the parameters of beating signal affect to the discomfort at idle vibration in passenger vehicle.

  • PDF

Enzyme beating 전처리를 통한 Micro-Fibrillated Cellulose 제조 및 지력증강 효과 (Micro-Fibrillated Cellulose Preparation with Enzyme Beating Pretreatment and Effect on Paper Strength Improvement)

  • 안은별;홍성범;김강재;엄태진
    • 펄프종이기술
    • /
    • 제47권6호
    • /
    • pp.57-65
    • /
    • 2015
  • Microfibrillated cellulose (MFC) or Nanofibrillated cellulose (NFC) has been used to reduce the use of raw pulp and to improve paper strength. The problem of MFC preparation is high manufacturing cost. In this study, it was carried out to prepare MFC after enzyme beating and estimated properties of MFC. Endo-D was the best beating efficiency among three type of endo-glucanase. As the grinder pass number increased, the viscosity and the fines of MFC suspension increased while the crystallinity and the porosity of MFC sheet decreased. Also enzyme beating MFC was higher value in the crystallinity and lower value in the viscosity than non-enzyme MFC. In addition, the aspect ratio of MFC was the highest at 5 pass. MFC addition improved the handsheet strength and the air permeability but worsened the drainage.

재미 한인 남성들의 아내 학대 태도 (Beliefs About Wife Beating Among Korean American Men)

  • 조인주
    • 사회복지연구
    • /
    • 제36호
    • /
    • pp.151-173
    • /
    • 2008
  • 본 연구는 재미 한인 남성들의 사회 인구학적 특성, 문화적응, 성역활 태도가 아내학대 태도에 어떤 영향을 미치는가를 분석하였다. 로스앤젤레스 카운티에 거주하고, 연령이 20세 이상 64세 이하이며, 결혼한 지 2년 이상으로 현재 부인과 함께 살고 있는 201명의 재미 한인 남성들을 대상으로 구조화된 질문지를 이용하여 자료를 수집하였다. 본 연구 분석에는 완성된 196명의 자료가 사용되었다. 아내학대 태도는 11개의 문장으로 구성된 Inventory of Beliefs About Wife Beating Short Form으로 측정되었다. 다중회귀분석 결과 연령과 성역활 태도는 응답자들의 아내학대 태도와 유의미한 연관성이 있는 반면, 아동기 가정폭력 목격과 문화적응은 아내학대 태도와 유의미한 연관성이 없는 것으로 나타났다. 연구 결과를 통해 정신건강 프로그램과 앞으로의 연구에 대한 함의가 제시되었다.