• Title/Summary/Keyword: Failure Rate Trend

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Feeding the Larvae of the Sea Urchin Strongylocentrotus intermedius on a Red-Tide Dinoflagellate Cochlodinium polykrikoides

  • Lee, Chang-Hoon
    • Journal of Aquaculture
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    • v.15 no.2
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    • pp.79-86
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    • 2002
  • This study is the first attempt to understand the feeding physiology of a sea-urchin larva on a red-tide dinoflagellate. Fifteen day old larvae of S. intermedius capture C. polykrikoides cells by localized reversal of ciliary beats. No failure to transporte the algal cells from theciliated band to mouth and no rejection at the mouth suggest that C. polykrikoides has no feeding deterrence to S. intermedius larvae. The trend obtained for the clearance rate of S. intermedius larvae is similar to that of other sea urchin larvae. Thus, the clearance rate decreased as the algal concentration increased. Maximum clearance rate of S. intermedius on C. polykrikoides was 17.7 $\mu l$/larva/hr. Ingestion rate rapidly increased at lower algal concentrations and saturated at higher concentrations. There was no inhibition in ingestion rate at the highest prey concentration of ca. 3000 cells/ml. Maximum ingestion rate of S. intermedius on C. polykrikoides was 131 ngC/larva/d, which is higher than that reported for the larvae of the mussel Mytilus gal-lotrovincialis, but lower than that of the ciliate Strombidinopsis sp. The grazing rate, calculated by combining the field data on algal abundances with experimental data on ingestion rate, suggests that due to its low abundance, sea urchin Iarva has no significant grazing impact on C. polykrikoides population.

Early hypopharyngeal cancer treated with different therapeutic approaches: a single-institution cohort analysis

  • Kim, Nalee;Lee, Jeongshim;Kim, Kyung Hwan;Park, Jong Won;Lee, Chang Geol;Keum, Ki Chang
    • Radiation Oncology Journal
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    • v.34 no.4
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    • pp.280-289
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    • 2016
  • Purpose: Early hypopharyngeal squamous cell carcinoma (HPSCC) is a rarely diagnosed disease, for which the optimal treatment has not been defined yet. We assessed patterns of failure and outcomes in early HPSCC treated with various therapeutic approaches to identify its optimal treatment. Materials and Methods: Thirty-six patients with stage I (n = 10) and II (n = 26) treated between January 1992 and March 2014 were reviewed. Patients received definitive radiotherapy (RT) (R group, n = 10), surgery only (S group, n = 19), or postoperative RT (PORT group, n = 7). All patients in both the R and PORT groups received elective bilateral neck irradiation. In the S group, 7 patients had ipsilateral and 8 had bilateral dissection, while 4 patients had no elective dissection. Results: At a median follow-up of 48 months, the 5-year locoregional control (LRC) rate was 65%. Six patients had local failure, 1 regional failure (RF), 3 combined locoregional failures, and 2 distant failures. There was no difference in 5-year LRC among the R, S, and PORT groups (p = 0.17). The presence with a pyriform sinus apex extension was a prognosticator related to LRC (p = 0.01) in the multivariate analysis. Patients with a bilaterally treated neck showed a trend toward a lower RF rate (p = 0.08). Conclusion: This study shows that patients with early stage HPSCC involving the pyriform sinus apex might need a tailored approach to improve LRC. Additionally, our study confirms elective neck treatment might have an efficacious role in regional control.

Effect of Breast-feeding Education and Follow-up care on the Breast-feeding Rate and the Breast-feeding Method - Focused on Home Visit and Phone Counselling - (모유수유교육과 추후간호방법이 산모의 모유수유실천율과 모유수유방법에 미치는 효과 - 가정방문과 전화상담을 중심으로 -)

  • Park, Sook-Hee;Koh, Hyo-Jung
    • Women's Health Nursing
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    • v.7 no.1
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    • pp.30-43
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    • 2001
  • This was a pre-experimental study to confirm the breast-feeding ability and effect of follow up care on the breast-feeding rate and the breast-feeding method by the mother-infant breast-feeding assessment tool for the mothers who got the breast-feeding education. The subjects were 46 mothers who experienced normal delivery of infants at a college hospital in K-city, Kyungsangbuk-do, from July 1 to October 21, 2000. The instrument for data obtainment were The Mother-Infant Breast-Feeding Assessment Tool of Johnson et al. (1999), and The Breast- Feeding Method Measurement Tool of Jeong, Geum-hee(1997). This instrument was reliable, showing Cronbach $\alpha$.751. This study classified them into 3 groups: at high risk for breast-feeding failure, at risk for breast-feeding problems, and at low risk for breast-feeding failure by the mother-infant breast-feeding assessment tool on the day of discharge from the hospital after delivering individual breast-feeding education to the subjects. This study investigated the breast-feeding rate and the breast-feeding method through mail questionnaire at the four week after childbirth, and through the phone counselling and the home visit for follow up care at the first week and the second week after childbirth. The sixth week after childbirth, this study investigated the breast-feeding rate by phone. The data analyzed the hypothesizes by $x^2$-test, paired t-test, ANOVA, Wilcoxon signed rank test, Wilcoxon rank sum test and trend analysis using SPSS/PC+ WIN 10.0 program. The results were as follows : 1) Hypothesis 1-1, "there won't be any difference the breast-feeding rate of a group at risk for breast-feeding failure by the time elapsed" was supported through constant the breast-feeding rate, because changes in the breast-feeding rate by the time elapsed after childbirth wasn't statistically significant(t= -1.501, p=.270). Hypothesis 1-2, "there won't be any difference the breast-feeding rate of group at low risk for breast-feeding failure by the time elapsed" was supported through constant the breast-feeding rate, because changes in the breast-feeding rate by the time elapsed after childbirth wasn't statistically significant(t=-1.732, p=.225). 2) Hypothesis 2-1, "there won't be any difference between the breast-feeding method of group at risk for breast-feeding failure for four weeks after childbirth and just after childbirth” was rejected, because the mean point of post test appeared to be higher than that of pre test(t=-7.267, p=.000). Hypothesis 2-2, "there won't be any difference between the breast-feeding method of the group at low risk for breast-feeding failure for four weeks after childbirth and just after childbirth" was rejected, because the mean point of post test appeared to be higher than that of pre test(t=-2.501, p=.012). 3)The 3rd hypothesis, "there won't be any difference between breast-feeding method of groups at risk for breast-feeding problems and at low risk for breast-feeding failure at the 4th week after childbirth and just after childbirth" didn't show any difference between the breast-feeding method of groups at risk for breast-feeding problems and at low risk for breast-feeding failure in the advance test(t=-1.521, p=.130) but there was difference between them in post test (t=-2.012, p=.044). As a result, the 3rd hypothesis was supported by pre test, but it was rejected by post test. In conclusion, this study confirmed breast- feeding education and follow up care just after childbirth were effective for the breast-feeding rate and method. Accordingly, it is proposed that successful nursing intervention of breast-feeding to be necessary by continuously providing follow up care through the mother-infant breast-feeding assessment tool as well as to execute individual breast-feeding education to mothers just after childbirth.

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NHPP Software Reliability Model based on Generalized Gamma Distribution (일반화 감마 분포를 이용한 NHPP 소프트웨어 신뢰도 모형에 관한 연구)

  • Kim, Hee-Cheul
    • Journal of the Korea Society of Computer and Information
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    • v.10 no.6 s.38
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    • pp.27-36
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    • 2005
  • Finite failure NHPP models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates Per fault. This Paper Proposes reliability model using the generalized gamma distribution, which can capture the monotonic increasing(or monotonic decreasing) nature of the failure occurrence rate per fault. Equations to estimate the parameters of the generalized gamma finite failure NHPP model based on failure data collected in the form of interfailure times are developed. For the sake of proposing shape parameter of the generalized gamma distribution, used to the special pattern. Data set, where the underlying failure process could not be adequately described by the knowing models, which motivated the development of the gamma or Weibull model. Analysis of failure data set for the generalized gamma modell, using arithmetic and Laplace trend tests . goodness-of-fit test, bias tests is presented.

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Study on the Transport Reliability Concerning Risks Scenarios (위험사건(Risk)발생 시나리오를 고려한 운송 신뢰성 연구)

  • Kim, Eun-Ji;Ganbat, Enkhtsetseg;Kim, Hwan-seong
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2015.10a
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    • pp.256-257
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    • 2015
  • The trend of globalization and the development of the communication-Information technology not only complexified the supply chain, but also, led to the needs of the high quality of logistics service for customers. I t defines risks that can occur in truck transport under unexpected situation with Fault Tree Analysis(FTA) and calculates failure rate concerning relationship between each risks. Based on the 4 kinds of middle failure events that defined in FTA, Reliability function which is regarded about risks sequentiality and time flow is resulted in. I t is meaningful that it calculates reliability of logistics and transportation system with engineering methodology.

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Development of Pre-heat-treated High Strength CHQ Wires and Forming Technology for them (고강도 냉간압조용 선조철강 및 제품화 기술 개발)

  • Yoon, D.J.;Kim, E.Z.;Ahn, S.T.;Son, Y.H.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2009.05a
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    • pp.35-36
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    • 2009
  • Development trend and current status were surveyed for pre-heat-treated high strength cold heading quality (CHQ) wire and it's forming technology. Spheroidizing, quenching, and tempering heat treatments are eliminated by adapting the pre-treated wire, which could reduce energy consumption rate and green house gas emission rate during produce parts requiring high strength. There are some challenging problems to expand application area such as enhancing forming tool life, and preventing delayed failure. Domestic research movement concerning the development and application of the new high strength wire was introduced.

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The study for NHPP Software Reliability Model based on Kappa(2) distribution (Kappa(2) NHPP에 의한 소프트웨어 신뢰성 모형에 관한 연구)

  • Kim, Hee-Cheul
    • Journal of the Korea Computer Industry Society
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    • v.6 no.5
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    • pp.689-696
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    • 2005
  • Finite failure NHPP models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this paper, Goel-Okumoto and Yamada-Ohba-Osaki model was reviewed, proposes the Kappa(2) reliability model, which can capture the nomotonic decreasing nature of the failure occurrence rate per fault. Algorithm to estimate the parameters used to maximum likelihood estimator and bisection method, model selection based on sum of the squared errors and Kolmogorov distance, for the sake of efficient model, was employed. Analysis of failure using real data set, SYS2(Allen P.Nikora and Michael R.Lyu), for the sake of proposing two parameter of the Kappa distribution, was employed. This analysis of failure data compared with the Kappa model and the existing model using arithmetic and Laplace trend tests, bias tests is presented.

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The Study for NHPP Software Reliability Model based on Chi-Square Distribution (카이제곱 NHPP에 의한 소프트웨어 신뢰성 모형에 관한 연구)

  • Kim, Hee-Cheul
    • Journal of the Korea Society of Computer and Information
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    • v.11 no.1 s.39
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    • pp.45-53
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    • 2006
  • Finite failure NHPP models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this paper, Goel-Okumoto and Yamada-Ohba-Osaki model was reviewed, proposes the $x^2$ reliability model, which can capture the increasing nature of the failure occurrence rate per fault. Algorithm to estimate the parameters used to maximum likelihood estimator and bisection method, model selection based on SSE, AIC statistics and Kolmogorov distance, for the sake of efficient model, was employed. Analysis of failure using real data set, SYS2(Allen P.Nikora and Michael R.Lyu), for the sake of proposing shape parameter of the $x^2$ distribution using the degree of freedom, was employed. This analysis of failure data compared with the $x^2$ model and the existing model using arithmetic and Laplace trend tests, Kolmogorov test is presented.

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Open Heart Surgery in Infants Weighing Less than 3kg (체중 3kg 이하 소아에서의 개심술)

  • 이창하
    • Journal of Chest Surgery
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    • v.33 no.8
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    • pp.630-637
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    • 2000
  • Backgroud: There are well-known problems in the management of low weight neonates or infants with congenital heart defects. In the past, because of a perceived high risk of operations using cardiopulmonary bypass(CPB) in these patients, there was a tendency for staged palliation without the use of CPB. However, the recent trend has been toward early reparative surgery using CPB, with acceptable mortality and good long-term survival. Therefore we reviewed our results of the operations in infants weighing less than 3kg and considered the technical aspect of conducting the CPB including myocardial protection. Material and Method: Between Jan. 1995 and Jul. 1998, 28 infants weighing less than 3kg underwent open heart surgery for many cardiac anomalies with a mean body weight of 2.7kg(range; 1.9-3.0kg) and a mean age of 41days(range; 4-110days). Preoperative management in the intensive care unit was needed in 20 infants and preoperative ventilator support therapy in 11. Total correction was performed in 23 infants and the palliative procedure in 5. Total circulatory arrest was needed in 11 infants(39%). Result: There were seven hospital deaths(25%) caused by myocardial failure(n=3), surgical failure(n=2), multiorgan failure(n=1), and sudden death(n=1). The median duration of hospital stay and intensive care unit stay were 13days(range; 6-93days) and 6days(range; 2-77days) respectively. The follow-up was achieved in 21 patients and showed three cases of late mortality(15%) and a one-year survival rate of 62%. No neurologic complications such as clinical seizure and intracranial bleeding were noticed immediately after surgery and during follow-up. Conclusion: The early and late mortality rate of open heart surgery in our infants weighing less than 3 kg stood relatively high, but the improved outcomes are expected by means of the delicate conduct of cardiopulmonary bypass including myocardial protection as well as the adequate perioperative management. Also, the longer follow-up for the neurologic development and complications are needed in infants undergoing circulatory arrest and continuous low flow CPB.

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The Study for Performance Analysis of Software Reliability Model using Fault Detection Rate based on Logarithmic and Exponential Type (로그 및 지수형 결함 발생률에 따른 소프트웨어 신뢰성 모형에 관한 신뢰도 성능분석 연구)

  • Kim, Hee-Cheul;Shin, Hyun-Cheul
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.9 no.3
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    • pp.306-311
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    • 2016
  • Software reliability in the software development process is an important issue. Infinite failure NHPP software reliability models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this paper, reliability software cost model considering logarithmic and exponential fault detection rate based on observations from the process of software product testing was studied. Adding new fault probability using the Goel-Okumoto model that is widely used in the field of reliability problems presented. When correcting or modifying the software, finite failure non-homogeneous Poisson process model. For analysis of software reliability model considering the time-dependent fault detection rate, the parameters estimation using maximum likelihood estimation of inter-failure time data was made. The logarithmic and exponential fault detection model is also efficient in terms of reliability because it (the coefficient of determination is 80% or more) in the field of the conventional model can be used as an alternative could be confirmed. From this paper, the software developers have to consider life distribution by prior knowledge of the software to identify failure modes which can be able to help.