• 제목/요약/키워드: VAT

검색결과 146건 처리시간 0.026초

조류발전용 수직축 터빈의 공진 회피 설계를 위한 프로그램 개발 (Development of Vibration Analysis Program for Anti-resonance Design of Vertical-axis Tidal Current Turbine)

  • 배재한;성혜민;조대승;김재호
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2012년도 춘계학술대회 논문집
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    • pp.336-341
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    • 2012
  • The vertical-axis tidal current turbine (VAT) consisting of blades, struts to support blades, shaft, generator and so forth requires anti-resonance design against fluid fluctuation forces generated on blades to ensure its stable operation. In this study, a free vibration analysis program based on the finite element method is developed for efficient anti-resonance design of VAT in the preliminary design stage. In the finite element modeling, the VAT structure components are regarded as beam elements. Added masses due to the fluid and structure interaction of VAT evaluated by empirical formulas are considered as lumped mass elements. In addition, input parameters required for the analysis can be automatically prepared from the principal dimensions of VAT to make anti-resonance design more convenient. The validity of applied methods is verified by the comparison of the numerical results obtained from MSC/Nastran and the developed program for two VAT models.

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수종(數種)의 침엽수(針葉樹) 단판용(單板用) 원목(原木)의 가열(加熱)과 냉각(冷却) 시간(時間) (Heating and Cooling Time for Veneer Bolt of Some Softwoods)

  • 정희석;이남호;여환명
    • Journal of the Korean Wood Science and Technology
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    • 제23권3호
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    • pp.16-22
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    • 1995
  • The profiles of the heating temperature in three water vat temperatures (55, 66 and 77$^{\circ}C$) and the cooling temperature under the average ambient temperature of 3$^{\circ}C$ in 4 and 10cm depths from surface at the center of veneer bolts length showed similar patterns for Japanese larch (Larix leptolepis). Dahurian larch (Larix gmelinei) and Radiata pine (Pinus radiata). The difference of these core temperatures of 10cm depth from surface varied proportionally with the increase of vat temperatures. The average heating time based on final core temperature of 6$^{\circ}C$ lower than vat temperature required about 14.5 hours in vat temperature of 55$^{\circ}C$ and 13.5 hours in vat temperature of 66and 77$^{\circ}C$. Each internal temperature of 4 and 10cm depths from surface started to decrease from the beginning of cooling and after about two hours.

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배트염료에 의한 나일론과 폴리에스테르 섬유의 염색성 - 색상 변화에 미치는 하이드로슬파이트와 NaOH의 영향 - (Dyeing Properties of Nylon 6 and Polyester Fabrics with Vat Dyes - Effect of Composition of Reducing Agent and Alkali on Color Change -)

  • 정동석;이두환;이문철
    • 한국염색가공학회지
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    • 제14권5호
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    • pp.284-293
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    • 2002
  • Nylon 6 and polyester taffeta fabrics are dyed in aqueous medium with vat dyes such as Indanthren Red FBB, Mikethren Blue ACE and Mikethren Blue HR varying the compositions of sodium hydrosulfite and NaOH. Also nylon UMF nonwoven and polyester UMF knitted fabrics are dyed with metal complex and disperse dyes as a reference, and the wash and rubbing fastnesses for these dyes are investigated. In vat dyeing of polyester and nylon taffeta, an optimum composition of sodium hydrosulfite/NaOH is existed at a range of 1∼2wt%/0.2wt%. A good build-up property for Mikethren Blue ACE on nylon 6 UMF nonwoven fabric is shown at high temperature. Vat dyeing of polyester with Mikethren Blue Ace shows a good color shade in a higher temperature, while dyeing with Mitsui Blue HR shows low temperatures. Vat dyes In dyeing of both nylon 6 UMF nonwoven and polyester UMF knitted fabrics have a better wash fastnesses compared with metal complex or disperse dyes.

Impact of Skeletal Muscle Loss and Visceral Obesity Measured Using Serial CT on the Prognosis of Operable Breast Cancers in Asian Patients

  • Mi-ri Kwon;Eun Sook Ko;Min Su Park;Woo Kyoung Jeong;Na Young Hwang;Jae-Hun Kim;Jeong Eon Lee;Seok Won Kim;Jong Han Yu;Boo-Kyung Han;Eun Young Ko;Ji Soo Choi;Ko Woon Park
    • Korean Journal of Radiology
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    • 제23권2호
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    • pp.159-171
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    • 2022
  • Objective: This study aimed to investigate the impact of baseline values and temporal changes in body composition parameters, including skeletal muscle index (SMI) and visceral adipose tissue area (VAT), measured using serial computed tomography (CT) imaging on the prognosis of operable breast cancers in Asian patients. Materials and Methods: This study retrospectively included 627 Asian female (mean age ± standard deviation [SD], 53.6 ± 8.3 years) who underwent surgery for stage I-III breast cancer between January 2011 and September 2012. Body composition parameters, including SMI and VAT, were semi-automatically calculated on baseline abdominal CT at the time of diagnosis and follow-up CT for post-treatment surveillance. Serial changes in SMI and VAT were calculated as the delta values. Multivariable Cox regression analysis was used to evaluate the association of baseline and delta SMI and VAT values with disease-free survival. Results: Among 627 patients, 56 patients (9.2%) had breast cancer recurrence after a median of 40.5 months. The mean value ± SD of the baseline SMI and baseline VAT were 43.7 ± 5.8 cm2/m2 and 72.0 ± 46.0 cm2, respectively. The mean value of the delta SMI was -0.9 cm2/m2 and the delta VAT was 0.5 cm2. The baseline SMI and VAT were not significantly associated with disease-free survival (adjusted hazard ratio [HR], 0.983; 95% confidence interval [CI], 0.937-1.031; p = 0.475 and adjusted HR, 1.001; 95% CI, 0.995-1.006; p = 0.751, respectively). The delta SMI and VAT were also not significantly associated with disease-free survival (adjusted HR, 0.894; 95% CI, 0.766-1.043; p = 0.155 and adjusted HR, 1.001; 95% CI, 0.989-1.014; p = 0.848, respectively). Conclusion: Our study revealed that baseline and early temporal changes in SMI and VAT were not independent prognostic factors regarding disease-free survival in Asian patients undergoing surgery for breast cancer.

수종의 분산 염료 및 환원염료에 의한 Polyester microfiber의 고견뢰 염색기술 (High Fastness Dyeing Technology of Polyester Microfiber with Several Disperse Dyes and Vat dye)

  • 백진주;권오대;손아름;이난형;김삼수
    • 한국염색가공학회지
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    • 제15권6호
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    • pp.1-7
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    • 2003
  • Polyester microfiber has usually greater dye uptake than normal denier polyester fiber in same dyeing condition. In spite of this high dye uptake dyed microfiber fabric has not only low visual colour depth but also poor washing fastness property. In order to study high colouring dyeing technology and high washing fastness of polyester microfiber, dyeing property of polyester microfiber was investigated according to the dye solubility and particle size of used disperse dyes in aqueous dye solution. After disperse dyeing, dyed fabric with disperse dye was redyed with a vat dye without reduction clearing in order to obtain a high washing fastness property. The result were as followings ; A small particle sized disperse dyes such as C. I. Disperse Blue 56 and Red 60 showed high rate of initial exhaution compared with a large particle sized disperse dyes like C. I. Disperse Blue 165 and Red 343. In study of dyeing property of polyester microfiber with C. I. Vat Blue 1, polyester microfiber could achieve high dye uptake at a given optimum vatting process conditions. On the other hand, in consecutive dyeing with disperse and vat dye, K/S value of polyester microfiber with a small particle sized disperse dye increased without reduction clearings, but K/S value of polyester microfiber with a large particle sized disperse dye decreased with reduction clearings.

국소마취하에 비디오 흉강경을 이용한 폐기포절제술 (Video-Assisted Thoracoscopic Bullectomy under Local Anesthesia)

  • 박만실
    • Journal of Chest Surgery
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    • 제27권2호
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    • pp.128-131
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    • 1994
  • Recently we performed video-assisted thoracoscopic[VAT] examination and bullectomy under local anesthesia. Of the 10 patients undergoing VAT examination under local anesthesia with primary spontaneous pneumothorax, 8 patients underwent VAT bullectomy under local anesthesia using endo-GIA; 7 patients discharged within 24 hours after operation; 1 patient had an air leak after operation, so chemical pleurodesis with doxycycline was performed and discharged postoperative day 3. There have been no recurrence to date[60-120 days after operation]. We think spontaneous pneumothorax can be treated on an out-patient basis.

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Dyeing and Fastness Properties of Vat Dyes on a Novel Regenerated Cellulosic Fiber

  • Lee Jung Jin;Shim Woo Sub;Kim Ik Soo;Kim Jae PH
    • Fibers and Polymers
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    • 제6권3호
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    • pp.244-249
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    • 2005
  • enVix is a novel regenerated cellulosic fiber, which is prepared from cellulose diacetate fiber using environmentally friendly manufacturing process. Vat dyeing properties of the enVix were investigated and compared with those ofregular viscose rayon. The enVix exhibited better dyeability than viscose rayon. The colour yields of vat dyes on the enVix were found to be dependent on dyeing temperature as well as the amount of levelling agent and salt. Good build-up and good to excellent fastness properties were obtained on the en Vix fabric.

인디고계 배트염료에 의한 합성섬유의 염색성 (Dyeing Properties of Synthetic Fibers with Indigoid Vat Dye)

  • 장혜영;김호정;이문철
    • 한국염색가공학회지
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    • 제13권5호
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    • pp.41-41
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    • 2001
  • In this study, synthetic fiber fabrics such as polyester, nylon 6, acrylic and acetate were dyed with indigoid vat dye. The effects of the composition of alkaline reduction, dyeing time and dyeing temperature on color strength and color fastness of the fabrics were investigated. Also the color fastnesses to wash and light of the dyed fabrics were studied. In dyeing of polyester, nylon, acrylic and acetate fiber fabrics with indigo vat dyes, it appears that these fabrics have high values of K/S up to Ig/L of sodium hydroxide and 6g/L of reducing agent. Indigo vat dyeing for synthetic fiber fabrics was verb fast, and lead to dyeing equilibrium within twenty minutes. The K/S values of dyed fabrics did not changed in dye concentration more than 10% o.w.f.. Synthetic fiber fabrics dyed with indigoid dyes had bad light fastness.

인디고계 배트염료에 의한 합성섬유의 염색성 (Dyeing Properties of Synthetic Fibers with Indigoid Vat Dye)

  • 장혜영;김호정;이문철
    • 한국염색가공학회지
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    • 제13권5호
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    • pp.329-335
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    • 2001
  • In this study, synthetic fiber fabrics such as polyester, nylon 6, acrylic and acetate were dyed with indigoid vat dye. The effects of the composition of alkaline reduction, dyeing time and dyeing temperature on color strength and color fastness of the fabrics were investigated. Also the color fastnesses to wash and light of the dyed fabrics were studied. In dyeing of polyester, nylon, acrylic and acetate fiber fabrics with indigo vat dyes, it appears that these fabrics have high values of K/S up to Ig/L of sodium hydroxide and 6g/L of reducing agent. Indigo vat dyeing for synthetic fiber fabrics was verb fast, and lead to dyeing equilibrium within twenty minutes. The K/S values of dyed fabrics did not changed in dye concentration more than 10% o.w.f.. Synthetic fiber fabrics dyed with indigoid dyes had bad light fastness.

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Vat dyeing of Wool and Cotton fabrics with Sepia Melanin

  • Kim, Su-Jin;Jang, Jin-Ho
    • 한국염색가공학회지
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    • 제22권2호
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    • pp.88-93
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    • 2010
  • Using extracted sepia melanin powder by repeated treatments with aqueous sodium hydroxide and acetic acid solutions, vat dyeing of wool and cotton fabrics was carried out under various dyeing conditions including concentration of melanin, alkali, reducing agent and salt, as well as dyeing time and temperature. A K/S of 25.3 for wool fabrics was obtained at the optimal dyeing condition with 9% owf melanin, 0.5g/L NaOH and 56g/L $Na_2S_2O_4$ without salt at $80^{\circ}C$ for 90minutes. The vat dyeing of sepia melanin was applicable to both cotton and wool fabrics but the wool showed higher dyeability. The color fastness properties of the dyed wool and cotton fabrics were excellent to washing, rubbing and light irradiation.