• 제목/요약/키워드: cycles

검색결과 5,754건 처리시간 0.033초

Freezing-thawing resistance evaluation of sandy soil, improved by polyvinyl acetate and ethylene glycol monobutyl ether mixture

  • Fard, Ata Rezaei;Moradi, Gholam;Ghalehjough, Babak Karimi;Abbasnejad, Alireza
    • Geomechanics and Engineering
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    • 제23권2호
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    • pp.179-187
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    • 2020
  • Freezing-thawing cycles have significant effect on soils engineering behavior in frozen areas. This effect is more considerable in fine-graded than coarse-grained soils. The objective of this study is improving soil durability and strength in continues freezing-thawing cycles. For getting this purpose mixture of Polyvinyl Acetate (PVAc) and Ethylene Glycol Monobutyl Ether (EGBE) has been added to fine-grained soil and final prepared samples were tested at different freezing-thawing cycles. PVAc was mixed with 1%, 2% and 3% of soil weight. Half of PVAc weight was used as weight of EGBE. Freezing-Thawing cycles were exposed to samples and they were tested at different cycles. Results showed that adding mixture of PVAc+EGBE improved strength and durability of samples up to 10 freezing-thawing cycles. Unconfined compress strength tests were applied to samples and stress and strain of samples were tested on failure time. Behavior of samples was different at different percentages of mixture. Results showed that increasing amount of PVAc from 1% to 2% had more considerable effect on final stress than 2% to 3%. Using higher percentages of PVAc + EGBE mixture leaded to that samples carried more strain before collapsing. Another result gained from tests was that, freezing-thawing effect was more considerable after fourth cycles. It means differences between first and fourth cycles were more considerable than differences between fourth and tenth.

Current status of assisted reproductive technology in Korea, 2011

  • Lee, Gyoung Hoon;Song, Hyun Jin;Lee, Kyu Sup;Choi, Young Min
    • Clinical and Experimental Reproductive Medicine
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    • 제43권1호
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    • pp.38-43
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    • 2016
  • Objective: The number of assisted reproductive technology (ART) clinics, ART cycles, clinical pregnancy rate (CPR), and number of newborns conceived using ART have steadily increased in South Korea. This aim of this study was to describe the status of ART in South Korea between January 1 and December 31, 2011. Methods: A localized online survey was created and sent to all available ART centers via email in 2015. Fresh embryo transfer (FET) cases were categorized depending on whether standard in vitro fertilization, intracytoplasmic sperm injection (ICSI), or half-ICSI procedures were used. Thawed embryo transfer (TET) and other related procedures were surveyed. Results: Data from 36,990 ART procedures were provided by 74 clinics. Of the 30,410 cycles in which oocytes were retrieved, a complete transfer was performed in 91.0% (n=27,683). In addition, 9,197 cycles were confirmed to be clinical pregnancies in the FET cycles, representing a pregnancy rate of 30.2% per oocyte pick-up and 33.2% per ET. The most common number of embryos transferred in the FET procedures was three (38.1%), followed by two (34.7%) and one (14.3%). Of the 8,826 TET cycles, 3,137 clinical pregnancies (31.1%) were confirmed by ultrasonography. Conclusion: While the overall clinical pregnancy rate for the TET cycles performed was lower than the rate reported in 2010 (31.1% vs. 35.4%), the overall CPR for the FET cycles was higher than in 2010 (33.2% in 2011 and 32.9% in 2010). The most common number of embryos transferred in FET cycles was three, as was the case in 2010.

Impact of Adjuvant Chemotherapy Cycles on Prognosis of Resectable Stomach Cancer: A Retrospective Analysis

  • Zhang, Wen-Ying;Zhang, Wen-Jun;Bai, Yu;Yuan, Hai-Hua;Liu, Feng;Gao, Jun;Gong, Yan-Fang;Jiang, Bin
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권1호
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    • pp.381-386
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    • 2013
  • Aims: The aim of this study was to investigate the effects of adjuvant chemotherapy cycles on the prognosis of patients with post-operative stomach cancer through retrospective analysis. Methods: A total of 128 patients with gastric cancer who underwent gastrectomy, followed by adjuvant chemotherapy consisting of epirubicin, cisplatin or oxaliplatin, leucovorin, and 5-fluorouracil, according to a defined schedule, were divided into three groups according to the number of chemotherapy cycles: Group I (<6 cycles); Group II (6 cycles); and Group III (>6 cycles). Results: The 5-year overall survival (OS) was 20.8% in Group I, 45.0% in Group II, and 42.9% in Group III, with a median follow-up of 43 months. The 5-year relapse-free survival (RFS) was 15.1% in Group I, 40% in Group II, and 40% in Group III. The OS and RFS in Groups II and III were significantly better than in Group I (OS, p = 0.002 and p=0.003; RFS, P<0.001 and P=0.002). There was no difference in OS (p = 0.970) or in RFS (p = 0.722) between Groups II and III. Multivariate Cox hazard analysis determined that the number of adjuvant chemotherapy cycles was an independent factor that influenced OS and RFS. Conclusion: Six cycles of adjuvant chemotherapy gave encouraging outcomes in patients with resectable gastric cancer. Further prospective randomized controlled investigations are warranted in a multi-center setting.

Efficacy of dual progesterone administration (intramuscular and vaginal) for luteal support in fresh day 3 or day 4 embryo transfer cycles

  • Nho, Eun Jee;Hong, Yeon Hee;Park, Ju Hee;Kim, Seul Ki;Lee, Jung Ryeol;Jee, Byung Chul;Kim, Seok Hyun
    • Clinical and Experimental Reproductive Medicine
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    • 제47권3호
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    • pp.227-232
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    • 2020
  • Objective: The aim of this study was to compare in vitro fertilization outcomes between fresh day 3 or day 4 embryo transfer cycles with dual progesterone (P) administration (intramuscular and vaginal) and cycles with single intramuscular P administration for luteal support. Methods: We selected 124 cycles from 100 women (under age 40 years) who underwent oocyte pick-up (number of trials ≤ 3, 4-14 oocytes obtained) and transfer of two or three day 3 or day 4 embryos at two infertility centers from January 2014 to June 2019. Dual P (intramuscular P [50 mg] daily+vaginal P) was used in 52 cycles and a single intramuscular administration of P (50 mg daily) was used in 72 cycles. Results: Women's age, infertility factors, number of oocytes retrieved, number of transferred embryos, and mean embryo score were similar between the dual P group and the single P group. Although the number of trial cycles was significantly higher (1.9 vs. 1.5), and the mean endometrial thickness on the trigger day (10.0 mm vs. 11.0 mm) was significantly lower in the dual P group, the implantation rate, clinical pregnancy rate, ongoing pregnancy rate, and miscarriage rate for both day 3 and day 4 transfers were similar between the two groups. Conclusion: In fresh day 3 or day 4 embryo transfer cycles, dual P administration did not demonstrate any clinical advantages. Intramuscular P alone appears to be sufficient for luteal support.

디자인 특성에 따른 니트 패션 트렌드의 주기 분석 (Analysis of Fashion Design Characteristics and Cycles of Knit Fashion Trends)

  • 고순영;박영선;박명자
    • 복식문화연구
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    • 제18권6호
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    • pp.1274-1290
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    • 2010
  • This study analyzed the design elements and fashion images of women's knitwear in collections of Paris, Milan, London and New York between 2003 and 2008, and examined knitwear trends in an effort to verify whether knitwear trends are repeated in certain cycles, whether they show complicated patterns in cycles and yet occur in quasi cycles, or whether they occur non-periodically in complicated forms of chaotic cycles. Trend cycle analysis results are deemed to identify the time series attribute of knit fashions. It also sought to categorize the attribute of various factors influencing knitwear trends with a view to determining relevancy between design elements, and to present the direction of predicting knitwear fashion trends and the progression of short-term knitwear trends. This study reached the following conclusion. According to design elements or fashion images, knitwear fashion trends occur in cycles, quasi cycles, non-periodical cycles. These cyclic characteristics can be used as scientific data for planning knitwear products. The study confirmed close relevancy between fashion images and fashion elements. It identified close relevancy between designs with similar fashion elements and images through coordinates by year and season, and it is possible to make short-term prediction of trend direction through the flow of coordinates. Time series data were insufficient, thereby making it difficult to perfectly verify chaos indices and giving limitations to this study. A study with more time series data will produce a more effective method of predicting and using knitwear fashion trends.

사이클 수 증가에 따른 엔진밸브 및 시트인서트 착좌면 마모 (A Wear of Engine Valve and Seat Insert Seating Face Depending on Cycle Numbers)

  • 김재희;전경진;홍재수;윤영한
    • 한국자동차공학회논문집
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    • 제15권4호
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    • pp.101-107
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    • 2007
  • This study investigated the wear of the valve and seat insert seating faces. A tester, an exhaust valve and a seat insert were used. Test variables were cycle numbers ($2{\times}10^6,\;4{\times}10^6,\;6{\times}10^6\;and\;8{\times}10^6$) and Hz (10Hz and 25Hz). The other test conditions such as temperature ($350^{\circ}C$), fuel (LPG) and load (1960N) were fixed. The 10Hz tests indicated that the average Rmax of the valve increased at the rate of $7.76{\mu}m/10^6$ cycles starting from $29.42{\mu}m$ at the $2{\times}10^6$ cycles and that of the seat insert increased at the rate of $8.57{\mu}m/10^6$ cycles starting from $34.19{\mu}m$ at the $2{\times}10^6$ cycles. The 25Hz tests indicated that the average Rmax of the valve increased at the rate of $1.58{\mu}m/10^6$ cycles starting from $74.2{\mu}m$ at the $2{\times}10^6$ cycles and that of the seat insert increased at the rate of $1.25{\mu}m/10^6$ cycles starting from $83.95{\mu}m$ at the $2{\times}10^6$ cycles. The tribochemical reaction product covered the two seating faces, preventing the wear of the seating faces. As cycle numbers became greater, the average Rmax of the seating faces became greater, but the increase rate varied significantly depending on the Hz. The wear mechanism of the two faces was investigated through the tribochemical reaction.

Associations of post-warming embryo or blastocyst development with clinical pregnancy in vitrified embryo or blastocyst transfer cycles

  • Hong, Yeon Hee;Lee, Jang Mi;Kim, Seul Ki;Youm, Hye Won;Jee, Byung Chul
    • Clinical and Experimental Reproductive Medicine
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    • 제47권2호
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    • pp.140-146
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    • 2020
  • Objective: To investigate whether the degree of post-warming embryo or blastocyst development is associated with clinical pregnancy in vitrified embryo or blastocyst transfer cycles. Methods: Ninety-six vitrified cleavage-stage embryos and 58 vitrified blastocyst transfer cycles were selected. All transfer cycles were performed from February 2011 to March 2019, and all vitrified embryos or blastocysts were warmed from 4 PM to 6 PM and then transferred the next morning from 9 AM to 10 AM. The scores of the cleavage-stage embryos and blastocysts were assessed at warming and at transfer using the modified Steer method and the Gardner method, respectively. The mean embryo or blastocyst score, score of the single top-quality embryo or blastocyst, and the difference in the score between warming and transfer were compared between nonpregnant and pregnant women. Results: In the cleavage-stage embryo transfer cycles, both the top-quality embryo score at transfer and the difference in the score between warming and transfer were significantly associated with clinical pregnancy. A top-quality embryo score at transfer of ≥ 60.0 (area under the curve [AUC], 0.673; 95% confidence interval [CI], 0.531-0.815) and a difference in the score between warming and transfer of ≥ 23.0 (AUC, 0.675; 95% CI, 0.514-0.835) were significant predictors of clinical pregnancy. In blastocyst transfer cycles, the top-quality blastocyst score at transfer was the only significant factor associated with clinical pregnancy. A top-quality blastocyst score at transfer of ≥ 38.3 was a significant predictor of clinical pregnancy (AUC, 0.666; 95% CI, 0.525-0.807). Conclusion: The top-quality embryo score at transfer and the degree of post-warming embryo development were associated with clinical pregnancy in vitrified cleavage-stage embryo transfer cycles. In vitrified blastocyst transfer cycles, the top-quality blastocyst score at transfer was the only significant factor affecting clinical pregnancy.

SOME PROBLEMS AND RESULTS ON CIRCUIT GRAPHS AND TRIANGULAR GRAPHS

  • Jung, Hwan-Ok
    • Journal of applied mathematics & informatics
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    • 제26권3_4호
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    • pp.531-540
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    • 2008
  • We discuss the decomposition problems on circuit graphs and triangular graphs, and show how they can be applied to obtain results on spanning trees or hamiltonian cycles. We also prove that every circuit graph containing no separating 3-cycles can be extended by adding new edges to a triangular graph containing no separating 3-cycles.

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Shear-fatigue behavior of high-strength reinforced concrete beams under repeated loading

  • Kwak, Kae-Hwan;Park, Jong-Gun
    • Structural Engineering and Mechanics
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    • 제11권3호
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    • pp.301-314
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    • 2001
  • The purpose of this experimental study is to investigate the damage mechanism due to shear-fatigue behavior of high-strength reinforced concrete beams under repeated loading. The relationship between the number of cycles and the deflection or strain, the crack growths and modes of failure with the increase of number of cycles, fatigue strength, and S-N curve were observed through a fatigue test. Based on the fatigue test results, high-strength reinforced concrete beams failed at 57-66 percent of static ultimate strength for 2 million cycles. The fatigue strength at 2 million cycles from S-N curves was shown as about 60 percent of static ultimate strength. Compared to normal-strength reinforced concrete beams, fatigue capacity of high-strength reinforced concrete beams was similar to or lower than fatigue capacity of normal-strength reinforced concrete beams. Fatigue capacity of normal-strength reinforced concrete beams improved by over 60 percent.