• 제목/요약/키워드: dormant

검색결과 262건 처리시간 0.023초

휴면기를 거치는 제품의 신뢰도 예측에 관한 연구 (A Study on Reliability Prediction of Product with Dormant Phase)

  • 김연수;정영배
    • 산업경영시스템학회지
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    • 제35권3호
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    • pp.173-179
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    • 2012
  • The purpose of this paper is to examine the effects on reliability of equipment or product which spends a great deal of its time in the dormant condition. Many systems experienced periods of dormancy throughout their life cycle, such as periods of operational storage where the system waits, ready for use. The design of such systems must account for how these period of dormant effects system performance. The methodology for predict and analysis was developed to support the evaluation of dormant modes of operation of systems and subsystems. For proper handling of the dormant environment, issues relating to dormant failures need to be taken into consideration from design stage of the lifecycle. Furthermore, the relevant environmental concerns that need to be taken into consideration depend on the environmental factors associated with each different target environment. This paper will look at dormant reliability, the possible dormant reliability models and the methodology on life cycle reliability which has different dormant phase.

Relationship between reactive oxygen species and autophagy in dormant mouse blastocysts during delayed implantation

  • Shin, Hyejin;Choi, Soyoung;Lim, Hyunjung Jade
    • Clinical and Experimental Reproductive Medicine
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    • 제41권3호
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    • pp.125-131
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    • 2014
  • Objective: Under estrogen deficiency, blastocysts cannot initiate implantation and enter dormancy. Dormant blastocysts live longer in utero than normal blastocysts, and autophagy has been suggested as a mechanism underlying the sustained survival of dormant blastocysts during delayed implantation. Autophagy is a cellular degradation pathway and a central component of the integrated stress response. Reactive oxygen species (ROS) are produced within cells during normal metabolism, but their levels increase dramatically under stressful conditions. We investigated whether heightened autophagy in dormant blastocysts is associated with the increased oxidative stress under the unfavorable condition of delayed implantation. Methods: To visualize ROS production, day 8 (short-term dormancy) and day 20 (long-term dormancy) dormant blastocysts were loaded with $1-{\mu}M$ 5-(and-6)-chloromethyl-2', 7'-dichlorodihydrofluorescein diacetate, acetyl ester (CM-$H_2DCFDA$). To block autophagic activation, 3-methyladenine (3-MA) and wortmannin were used in vivo and in vitro, respectively. Results: We observed that ROS production was not significantly affected by the status of dormancy; in other words, both dormant and activated blastocysts showed high levels of ROS. However, ROS production was higher in the dormant blastocysts of the long-term dormancy group than in those of the short-term group. The addition of wortmannin to dormant blastocysts in vitro and 3-MA injection in vivo significantly increased ROS production in the short-term dormant blastocysts. In the long-term dormant blastocysts, ROS levels were not significantly affected by the treatment of the autophagy inhibitor. Conclusion: During delayed implantation, heightened autophagy in dormant blastocysts may be operative as a potential mechanism to reduce oxidative stress. Further, ROS may be one of the potential causes of compromised developmental competence of long-term dormant blastocysts after implantation.

카드산업에서 휴면 고객 예측 (Prediction of Dormant Customer in the Card Industry)

  • 이동규;신민수
    • 서비스연구
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    • 제13권2호
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    • pp.99-113
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    • 2023
  • 고객 기반의 산업에서 고객 Retention은 기업의 경쟁력이라 할 수 있으며, 고객 Retention을 높이는 것은 기업의 경쟁력을 높이는 것이라 할 수 있다. 따라서, 미래 휴면 고객을 잘 예측하여 관리하는 것은 기업의 경쟁력을 높이는데 무엇보다 중요하다. 왜냐하면, 신규 고객을 유치하는데 필요한 비용이 기존 고객을 Lock-in 시키는데 드는 비용 보다 많은 것으로 알려져 있기 때문이다. 특히, 수 많은 카드사가 존재하는 국내 카드 산업의 휴면 카드를 관리하고자 정부에서 휴면 카드 자동 해지 제도를 도입하고 있으며, 카드 산업에서 휴면 고객을 관리하는 것이 무엇보다 중요한 과제로 떠오르고 있다. 본 연구에서는 카드 산업에서 휴면 고객을 예측하기 위해 Recurrent Neural Network (RNN)방법론을 사용하였으며, RNN방법론 중에서 긴 시간을 효율적으로 학습할 수 있는 Long-Short Term Memory (LSTM)을 활용하였다. 또한, 통합기술수용이론 (UTAUT)을 입각하여 카드 산업에서 휴면 고객을 예측하는데 필요한 변수를 재정의하였다. 그 결과 안정된 모형의 정확도와 F-1 score를 얻을 수 있었으며, Hit-Ratio를 통하여 모형의 안정된 결과를 입증하였다. 기존 연구에서 지적된 통합기술수용이론 (UTAUT)에서 발생 될 수 있는 인구통계학적 정보의 조절 효과도 발생 되지 않은 것을 보였으며, 이로 인해 통합기술수용이론(UTAUT)를 이용한 변수 선정 모형에서 LSTM을 이용한 휴면 고객 예측 모형은 편향되지 않고 안정된 결과를 가져다 줄 수 있다는 것을 입증하였다.

Search for dormant comets in AcuA

  • 김윤영
    • 천문학회보
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    • 제38권1호
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    • pp.62.2-62.2
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    • 2013
  • It is considered that comets near the ecliptic plane have been injected into inner solar system from Kuiper-belt. Some of them are still active while others are dormant with no detectable tails and comae. These dormant comets have eccentric and/or inclined orbits, which are parameterized by Tisserand parameter TJ<3. In addition, dormant comets can be differentiated from asteroids based on the albedo, because they have low albedo (the geometrical albedos pv<0.1). The conditions of TJ<3 and pv<0.1 have been used as a criteria to discriminate dormant comets from asteroids. However, we must be more careful because there are 'contaminations' from the outer region, i.e. Jovian Trojans (5.05

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산지삼포에서 면삼율 결주율 및 토양화학성의 상호관계 (Relationship among Dormant Root Rate Missing Root Rate and Soil Chemical Characteristics in Ginseng Plantations)

  • 박훈;김갑식;변정수
    • 한국작물학회지
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    • 제30권2호
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    • pp.180-183
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    • 1985
  • 산지삼포에서 면삼율과 결근율을 조사하여 토양의 화학성과 단순상관 관계를 보았다. 면삼율은 근령에 관계가 없었고 결근율과 정상관을 보이는 경우가 많았다. 면삼율은 토양의 유효인산함량 및 인산일수분비와 유의정상관을 보였다. 결근율은 토양 수분 및 Ca과 유의부상관, 인산일수분비와 유의정상관을 보였다. 이상의 결과는 면삼과 결근의 공통요인으로 토양인산의 과다와 토양수분의 부족임을 시사한다.

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Identification of ${\gamma}-Glutamylamine$ Cyclotransferase, as the Preform Enzyme at the Dormant Stage, From Soybean (Glycine max) Seeds

  • Kang, Hyeog;Park, Sung-Joon;Cho, Young-Dong
    • BMB Reports
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    • 제30권6호
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    • pp.438-442
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    • 1997
  • ${\gamma}-Glutamylamine$ cyclotransferase was purified to homogeneity from soybean (Glycine max) seeds. To our knowledge, it is the first purification of the enzyme from plant origins. The molecular weight of the enzyme estimated by Sephacryl S-300 gel filtration and SDS-PAGE was 27,000, indicating that the enzyme is a monomer. The optimal pH for activity was 8.6. The Km value for ${\gamma}-glutamyldansylcadaverine$ was 11 ${\mu}M$. The enzymatic activity was substantially inhibited by the addition of p-chloromercuribenzoate and partially inhibited by the $Cu^{2+}$ ion. However, neither other modification reagents nor other divalent metal ions affected the enzymatic activity. The comparison between the enzymatic activities of seed extracts treated with cycloheximide and control extracts, and the detection of the same single protein band by western blot analysis at the dormant stage without inhibition with distilled water indicate that ${\gamma}-Glutamylamine$ cyclotransferase is already present at the dormant stage and gradually activated during germination in soybean seeds.

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콩과식물인 아까시나무(Robinia pseudo-acacia), 등나무(Wistaria floribunda) 및 해녀콩(Canavalia lineata)에서 canavanine과 유리아미노산의 분포 (Distribution of Canavanine and Free Amino Acids in Legumes, Robinia pseudo-acacia, Wistaria floribunda, and Canavalia lineata)

  • Yu, Gyung-Hee;Young Myung Kwon
    • The Korean Journal of Ecology
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    • 제18권4호
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    • pp.433-440
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    • 1995
  • The constituents and proportions of non-protein free amino acids including canavanine were measured in roots and leaves of legumes, Robinia pseudo-acacia L., Wistaria floribunda L., and Canavalia lineata L. by using high performance liquid chromatography during dormant and fertilizing seasons. in all the three plant species, asparagine was the most abundant amino acid occurring 30% of total free amino acids, and canavanine was the second most abundant amino acid contributing 10% of total free amino acids throughout dormant and fertilizing seasons. In dormant season, roots contained 2 to 3 folds of free amino acids including canavanine and asparagine compared to those in fertilizing season. When proportions of asparagine and canavanine to total gree amino acids in various parts of C. lineata were examined in fertilizinng season, the level of asparagine was the highest in roots while that of canavanine was in seeds. On the basis of these results, it is assumed that canavanine appears and functions as a nitrogen-storing compound in roots and leaves throughout the whole life cycle of the investigated plants.

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Effects of Gibberellic Acid and Gibberellin Biosynthesis Retardants on Ethylene Production, Batatasins, and Free Sugars in Dormant Tubers of Chinese Yam

  • Kim Sang-Kuk;Lee Sang-Chul;Kim Kil-Ung;Choo Yeon Sik;Kim Hak Yoon;Lee In-Jung
    • 한국작물학회지
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    • 제49권4호
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    • pp.300-304
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    • 2004
  • Gibberellic acid did not affect ethylene production, whereas gibberellin biosynthesis inhibitors triggered ethylene production in dormant tubers. Gibberellic acid did not induce sprouting of dormant tubers, however, treatment of gibberellin biosynthesis retardants enhanced sprouting rates. Sprouting rate in ancymidol-treated tubers was highest among gibberellin biosynthesis retardants. Sprouting rate of tubers treated with ancymidol increased to $91.4\%$. Batatasin-III content in $GA_3$ treated tuber was increased in the highest concentration $(30{\mu}g\;I^{-1})$. Tubers treated with mepiquat chloride, Batatasin-I was increased steadily, but contents of Batatasin-III and V showed dramatic decrease at the $ 1,000{\mu}g\;I^{-1})$ concentration. This infers that gibberellin biosynthesis retardants play key roles in promoting breaking dormancy on dormant tubers of Chinese yam.

Search for Dormant Comets in the Infrared Asteroidal Catalog

  • Kim, Yoonyoung;Ishiguro, Masateru;Usui, Fumihiko
    • 천문학회보
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    • 제39권1호
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    • pp.67.2-67.2
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    • 2014
  • Comet nucleus is a solid body consisting of dark dust grains and ice. Cometary volatiles sublimate from subsurface layer by solar heating, leaving behind large dust grains on the surface. Eventually, the appearance could turn into asteroidal rather than cometary. It is, therefore, expected that there would be "dormant comets" in the list of known asteroids. Our research group has undertaken the research on the population of dormant comets. We applied a brand-new asteroidal catalog compiled from data garnered by three infrared astronomical observatories, AKARI, IRAS and WISE. We extracted objects which have comet-like orbits on the basis of their orbital properties (Tisserand parameters with respect to Jupiter, TJ, and aphelion distance, Q). We found that (1) there are a considerable number (>100) of asteroids in comet-like orbits, and (2) 80% of them have low albedo consistent with comets. This result suggest that these low albedo objects could be dormant comets. One unanticipated finding is that 20% of asteroids in comet-like orbit have high albedo similar to S-type asteroids. It is difficult to explain the population of S-type asteroids in comet-like orbits by the classical mechanics theory. We further found that these high-albedo objects are small (D < 2 km) bodies distributed in near-Earth space. We suggest that such high-albedo, small, near-Earth asteroids are susceptible to Yarkovsky effect and injected into comet-like orbits.

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비활성화 세포, Persister 세포와 VBNC(Viable but Non-Culturable Cells)의 이해 (Understanding Dormant Cells: Persister Cells and Viable but Non-Culturable Cells)

  • 김혜인;송수연
    • Journal of Dairy Science and Biotechnology
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    • 제41권4호
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    • pp.157-162
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    • 2023
  • In the field of microbiology, numerous types of bacteria live dormant to survive stresses such as pasteurization and antibiotics. Some bacteria become 'persisters' by inactivating their ribosomes, allowing them to 'sleep' through stress and revive when the stress has been removed. Under stress, some cells morph into hollow, lifeless structures known as 'cell shells.' In microbiology, these cells have been confused with viable cells in the 'viable but non-culturable cells' phenomenon. Therefore, this review addressed the concept that when revival occurs, the always-viable persister cells revive, instead of the dead cell husks.