• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4595-4598
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• 2013

We conducted a comprehensive study to investigate the role of genes involved in transport pathways in response to chemotherapy and clinical outcome of osteosarcoma cases. Genotyping of six SNPs was performed in a 384-well plate format on the Sequenom MassARRAY platform for 208 osteosarcoma patients to reveal any correlations of the six SNPs with response to chemotherapy and clinical outcome. Individuals with the ABCB1 rs1128503 TT and ABCC3 rs4148416 TT genotypes had a higher probability of responding poorly to chemotherapy, indicated by odds ratios (ORs) of 2.46 (95%CI, 1.21-5.74) and 3.78 (95% CI, 1.20-13.85), respectively. Moreover, the ABCB1 rs1128503 TT and ABCC3 rs4148416 TT genotypes were significantly associated with shorter diseasefree survival (DFS) and overall survival (OS). Our study found the two SNPs in two transporter genes and one phase II metabolism enzyme to be associated with response to chemotherapy and overall survival in osteosarcoma patients, suggesting potential prognostic biomarker applications of the two SNPs.

• The Korean Journal of Applied Statistics
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• v.35 no.1
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• pp.35-47
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• 2022

The receiver operating characteristic (ROC) curve was developed to quantify the classification ability of marker values (covariates) on the response variable and has been extended to survival data with diverse missing data structure. When survival data is understood as binary data (status of being alive or dead) at each time point, the ROC curve expressed at every time point results in time-dependent ROC curve and time-dependent area under curve (AUC). In particular, a follow-up study brings the change of cohort and incomplete data structures such as censoring and competing risk. In this paper, we review time-dependent ROC estimators under several contexts and perform simulation to check the performance of each estimators. We analyzed a dementia dataset to compare the prognostic power of markers.

• Journal of the Korea Society for Simulation
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• v.25 no.3
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• pp.53-63
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• 2016

We consider simulation study combining static and mobile decoys for survivability of a surface warship against torpedo attack. It is assumed that an enemy torpedo is a passive acoustic homing torpedo and detects a target within its maximum target detection range and search beam angle by computing signal excess via passive sonar equation, and a warship conducts an evasive maneuvering with deploying static and mobile decoys simultaneously to counteract a torpedo attack. Suggesting the four different decoy deployment plans to achieve the best plan, we analyze an effectiveness for a warship's survival probability through Monte Carlo simulation, given a certain experimental environment. Furthermore, changing the speed and the source level of decoys, the maximum torpedo detection range of warship, and the maximum target detection range of torpedo, we observe the corresponding survival probabilities, which can provide the operational capabilities of an underwater defense system.

• Journal of the Korea Institute of Military Science and Technology
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• v.23 no.3
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• pp.277-285
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• 2020

Survivability in a battle field is the most important aspect to the warriors. To analyze the survival effectiveness of warrior platform, the simulation via war-game model is an essential step in advance to the development of platform. In this study, Army Weapon effectiveness Analysis Model(AWAM) was utilized for analysis. Several weapon parameters were adjusted to apply the characteristics of warrior platform in some cases of the defense and survival system. Especially, adjusted triage possibility, probability of kill, fatality and accuracy were employed as parameters in the simulation program to evaluate the survival effectiveness of intelligent system based on the previous researches. In the future battle field or virtual space in the AWAM, the warrior platform intelligent system could react emergency treatment on time by expoiting the bio-information of man at arms. Considering the order of supply priority, special force was selected as operating troops and battle scenario without engagement was selected to measure accurate survival effectiveness. In conclusion, the survivability of defence and survival system of the warrior platform was about 1.47 times higher than that of current system.

• Communications for Statistical Applications and Methods
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• v.16 no.4
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• pp.557-572
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• 2009

This article examines the financial soundness of the government employee pension system(GEPS). We use a model that simplifies the existing GEPS considering survival probability distribution of the life of employees. Two approaches were selected for the research: One is the expected net value of pension for an individual employee and the other is the default probability of the system from Monte-carlo simulation. The outcome reveals following three possibilities. First of all, the individual expected net value presents unfairness between the retiree's premium and the benefit he/she receives. Secondly, the Monte-carlo simulation suggests that the default is highly likely to happen in less than 30 years. Thirdly, the governmental reserve and subsidy for GEPS should be required to a certain degree in order to alleviate the probability of default less than 5 percent for the next 30 years.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.54 no.10
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• pp.480-486
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• 2005

This paper proposes a method to consider an aging failure probability and survival probability of power system components, though only aging failure probability has been considered in existing mean life calculation. The estimates of the mean and its standard deviation is calculated by using Weibull distribution, and each estimated parameters is obtained from Data Analytic Method (Type H Censoring). The parameter estimation using Data Analytic Method is simpler and faster than the traditional calculation method using gradient descent algorithm. This paper shows calculation procedure of the mean life and its standard deviation by the proposed method and illustrates that the estimated results are close enough to real historical data of combustion turbine generating units in Korean systems. Also, this paper shows the calculation procedures of a probabilistic failure prediction through a stochastic data analysis. Consequently, the proposed methods would be likely to permit that the new deregulated environment forces utilities to reduce overall costs while maintaining an are-related reliability index.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.3861-3866
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• 2015

Background: The aim of this study was to analyze the patterns of relapse and survival outcomes in Northern Thai women with recurrent endometrial cancer (EC). Materials and Methods: Medical records were abstracted from EC patients who underwent primary surgery from 1999 to 2012. Data on clinicopathologic variables, sites of first recurrence, time to relapse of disease, and overall survival (OS) was analyzed. Associations between the clinicopathological variables and the rates of disease recurrence were determined. Results: Among 1,204 reviewed records, 42 eligible patients were identified with recurrent disease. The median age was 55 years and the median follow-up time was 26.0 months. The median times to recurrence (TTR) after completion of the initial treatment in the group of local relapse (LR) and distant/combined sites of recurrence (DCSR) was 6.6 (95% CI=4.6 to 8.6 months) and 16.9 months (95% CI=5.6 to 28.2 months), respectively (p=0.36). The 2-year survival and 3-year survival probability in the group of LR was 54.2% (95% CI=27.2 to 81.3%) and 34.7% (95% CI=9.2 to 60.2%), compared to 50.4% (95% CI=41.1 to 59.7%) and 42.1% (95%CI= 24.1 to 60.1%) for those with DCSR. Distant recurrence was the most frequent pattern of relapse. Overall survival was not significantly different in patients with local relapse when compared to those with DCSR (p=0.69). Conclusions: Patients with recurrence of EC after primary treatment had a worse prognosis and clinical aggressiveness. LR and DCSR occurred most during the first three years. The common sites of relapses were vaginal cuff, pelvis, and lungs. No significant clinicopathological predictor for survival outcomes was identified.

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.513-521
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• 2019

With rapid climate change and increasing global warming, the distribution of evergreen broad-leaved trees (EBLTs) is gradually expanding to the inland regions of Korea. The aim of the present study was to analyze the survival rate of 148 EBLT plantations measuring 180 ha and to determine the optimal plantation size that would help in coping with climate change in the warm, temperate climate zone of the Korean peninsula. For enhancing the reliability of our estimated survival model, we selected a set of 11 control variables that may have also influenced the survival rates of the EBLTs in the 148 plantations. The results of partial correlation analysis showed that the survival rate of 67.0±26.9 of the EBLTs in the initial plantation year was primarily correlated with plantation type by the crown closure of the upper story of the forest, wind exposure, and precipitation. For predicting the probability of survival by quantification theory, 148 plots were surveyed and analyzed with 11 environmental site factors. Survival rate was in the order of plantation type by the crown closure of upper story of the forest, wind exposure, total cumulative precipitation for two weeks prior to planting, and slope stiffness in the descending order of score range in the estimated survival model for the EBLTs with the fact that survival rate increased with shade rate of upper story to some extent.

• Journal of Korean Institute of Industrial Engineers
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• v.40 no.2
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• pp.151-162
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• 2014

This study proposes an optimization model to plan the patient distribution and medical resource allocation considering the diverse characteristics of disaster. For reflecting the particularity of disaster response, we configured a few scenarios such as availability of emergency surgery of non-major medical staff and the change in number of patients estimated reflecting the uncertainty, urgency and convergence of disaster. And we finally tested the effects of the scenarios' combination on the objective function defined as maximum number of survival patients. Our experimental results are expected to highlight the significance of the proposed model as well as the applicability of scenarios under disaster response.

• Weed & Turfgrass Science
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• v.7 no.3
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• pp.275-282
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• 2018

Miscanthus species are known as a genus of eco-friendly and low-maintenance cost ornamental grasses. Plug and cutting methods were tested for multi-propagation of most promising ornamental Miscanthus species in greenhouse and field plot. The plug formation period with three different cell sizes with four cultivars (M. sinensis 'Andersson', 'Strictus', 'Gracillimus', 'Variegatus') were evaluated the seedling development stages with two irrigation types of the over-head and the bottom watering in greenhouse and field plot afterward during 2015-2016 season. In seedling plug test, the size of tray cell affected the plug formation. Bottom irrigation resulted positively on plant height, weight, root and tiller development compared with the over-head irrigation. Plug cell size affected the plant growth in the field after transplanting. All of the 3 Miscanthus species showed higher rates of successful propagation at the lower nodes before inflorescence formation (vegetative growth stage). To analyze the survival factors of M. xgiganteus cutting, the cutting time, node part, and culm diameter were tested as independent variables with the binary logistic model. The survival probability was influenced by node part and culm diameter significantly. The third and fifth node parts showed 0.12 (8X higher failure probability) and 0.02 (50X higher failure probability) times less survival probability. It means the survival probability will be increased by using older and lower part of cuttings during a vegetative growth stage before inflorescences of M. xgiganteus.