• Title/Summary/Keyword: beating

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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
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    • v.55 no.1
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    • pp.55-60
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    • 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.

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

  • 이강진;박중문
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.30 no.2
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    • pp.47-54
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    • 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.

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

  • 김봉용
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.31 no.2
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    • pp.58-63
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    • 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.

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

  • Jeon, Hyeong-Ju;Sohn, Kyung-Hee;Park, Hyun-Kyung
    • Journal of the Korean Society of Food Culture
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    • v.10 no.2
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    • pp.75-81
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    • 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.

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

  • Kim, Jong-Su;Kim, Dae-Won
    • 연구논문집
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    • s.28
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    • pp.89-100
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    • 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.

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

  • Kil, Jung-Ha;Shin, Hyeon-Sik;Lee, Jin-Ho;Park, Jong-Moon
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.45 no.2
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    • pp.27-32
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    • 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.

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- (경주지역 평기와의 타날형태 변화에 대한 검토 -단판·중판·인장 그리고 장판으로-)

  • Cha, Soon-chul
    • Korean Journal of Heritage: History & Science
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    • v.40
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    • pp.73-104
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    • 2007
  • Centering around ruins recognized of being relatively early stage related to flat tile and brick, excavated in Silla capital area, the study attempted elementary approach to seek the appearance time of every remain through comparing them from the excavated cases and production methods of Short beating, Medium beating plate, Long beating plate and Stamped-roof tile. Gyeongju began to use the short beating plate made of tile-less plates or tile plate and increased its quantity. That is deemed to be due to efficiency of beating plate making methods, and moreover to be limited only for use in the palace castle and offices. That is, making short beating plates is presumed to be made merely under some definite objectives. Medium beating plate has been spread to the whole country since Silla and Baekje united. Differently from Koguryo and Baekje, Silla had its unique Beating-plates making technology available for mass-production, which was spread to the whole country and resulted in disappearing of Koguryo and Baekje technology. Long beating plate was not nearly founded in Gyeongju area, but flat tile and common tile excavated in Sachunwang Temple site and Samrang Temple 3rd remains are known. In the outskirts of Gyeongju, long beating plate appeared between the latter half of 8C and the beginning of 9C. Until now, different views have raised to appearance of long beating plate of Unified Silla, which is expected to be clarified under the situation excavated by position relations. Stamped-roof title in Gyeongju is estimated as used after the datum point year 679. While in Baekje area, five stems and branches were involved, in Silla area, code or sign was shown much. The difference between two areas would be due to each other factory, and especially the marked contents werenot letters, which means it had been changed from Baekje s existing-methods. That is, it says the production environment changed owing to Silla's merging. And stamped-roof tile was temporarily used in Gyeongju but soon disappeared, which was because Silla beating plates made under cylinder-shaped tile barrel(圓筒瓦桶) and hitting-pressing of Medium beating plate had beenspread to the whole country, so the production technology of Koguryo and Baekje was naturally dismissed. In consequence, the mergence by Silla brought about unification of each nation's special technology.

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

  • Park, Jinhan;Ahn, Sejin;Jeong, Weuibong
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2014.10a
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    • pp.247-249
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    • 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.

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

  • Ahn, Eun-Byeol;Hong, Sung-Bum;Kim, Kang-Jae;Eom, Tae-Jin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.47 no.6
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    • pp.57-65
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    • 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.

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

  • Cho, In-ju
    • Korean Journal of Social Welfare Studies
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    • no.36
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    • pp.151-173
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    • 2008
  • This study examined how socio-demographic and background characteristics, acculturation, and gender role attitudes influence Korean American male adults' beliefs about wife beating. Using a structured self-administered questionnaire, data was collected from 201 Korean American men between the ages of 20 and 64, married for at least two years, currently living with a wife, and residing in Los Angeles County. Of the 201, 196 completed questionnaires were used to analyze the data. The respondents' beliefs about wife beating were measured by the Inventory of Beliefs About Wife Beating(IBWB) Short Form, consisting of 11 items. The multiple regression analyses revealed that age and traditional gender role attitudes were significantly associated with the respondents' beliefs about wife beating, but no significant associations between witnessed parental abuse and acculturation and beliefs about wife beating were found. Implications of the findings for mental health programs and future research are discussed.