• Journal of the Korean Society for Railway
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• v.15 no.5
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• pp.517-523
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• 2012

Double Stack Train(DST) is being used variously around USA and Canada. The greatest advantage of the DST is mass transportation without extending the length of freight train and number of cars. So the DST system can be a kind of innovative train to increase the competitiveness of rail logistic business. As the domestic rail logistic increase, for enhancement of environment friendly green transportation amount, the DST needs more for efficiency. In this study, as the alternative way to introduce the DST to the Kyungbu Line, it's investigated the extensibility of rail freight with the relation of rail fare discount and examined the necessity of pilot business to the Kyungjeon Line which was expected comparatively lower cost. If the DST system is introduced to the Kyungjeon Line, the cost of mass transportation can be much lower and then the comparativeness of rail transportation will be increased, therefore logistic companies can have some margin additionally. In the result of survey to the related companies, if rail transportation fare is 37.7 % cheaper than current road transportation fare, the modal shift can be transferred by maximum 100%.

• Journal of Korean Society for Quality Management
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• v.34 no.4
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• pp.125-132
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• 2006

An adjusted control limit of the $\overline{X}$ chart is proposed for monitoring the continually improving processes. The continual improvement of the process implies the decrease of the process variance, which is represented by a logistic curve. The process standard deviation is estimated by the exponentially weighted moving average of the sample standard deviations from the past to the current times. The control limits are adjusted by the estimated standard deviation at every sampling time. The performance of the adjusted control limit is compared with that of the standard control limits for various cases of the decreasing speed and size of the variance. The results show that the $\overline{X}$ chart with the adjusted control limits provides better performances for monitoring the small and moderate shifts in continually improving processes.

• Korean Journal of Radiology
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• v.25 no.1
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• pp.43-54
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• 2024

Objective: To evaluate the added value of diffusion-weighted imaging (DWI)-based quantitative parameters to distinguish uterine sarcomas from atypical leiomyomas on preoperative magnetic resonance imaging (MRI). Materials and Methods: A total of 138 patients (age, 43.7 ± 10.3 years) with uterine sarcoma (n = 44) and atypical leiomyoma (n = 94) were retrospectively collected from four institutions. The cohort was randomly divided into training (84/138, 60.0%) and validation (54/138, 40.0%) sets. Two independent readers evaluated six qualitative MRI features and two DWI-based quantitative parameters for each index tumor. Multivariable logistic regression was used to identify the relevant qualitative MRI features. Diagnostic classifiers based on qualitative MRI features alone and in combination with DWI-based quantitative parameters were developed using a logistic regression algorithm. The diagnostic performance of the classifiers was evaluated using a cross-table analysis and calculation of the area under the receiver operating characteristic curve (AUC). Results: Mean apparent diffusion coefficient value of uterine sarcoma was lower than that of atypical leiomyoma (mean ± standard deviation, 0.94 ± 0.30 10^-3 mm²/s vs. 1.23 ± 0.25 10^-3 mm²/s; P < 0.001), and the relative contrast ratio was higher in the uterine sarcoma (8.16 ± 2.94 vs. 4.19 ± 2.66; P < 0.001). Selected qualitative MRI features included ill-defined margin (adjusted odds ratio [aOR], 17.9; 95% confidence interval [CI], 1.41-503, P = 0.040), intratumoral hemorrhage (aOR, 27.3; 95% CI, 3.74-596, P = 0.006), and absence of T2 dark area (aOR, 83.5; 95% CI, 12.4-1916, P < 0.001). The classifier that combined qualitative MRI features and DWI-based quantitative parameters showed significantly better performance than without DWI-based parameters in the validation set (AUC, 0.92 vs. 0.78; P < 0.001). Conclusion: The addition of DWI-based quantitative parameters to qualitative MRI features improved the diagnostic performance of the logistic regression classifier in differentiating uterine sarcomas from atypical leiomyomas on preoperative MRI.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.179-182
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• 1999

A protections from the frost damage at early ages is one of the serious problems to be considered in cold weather concreting. Frost damage at early ages brings about the harmful influences on the concrete structures such surface cracks and the loss of strength. Therefore, in this paper, the protecting durations of frost damage at early ages according to the standard specifications provided in KCI(Korean Concrete Institute) are suggested by appling logistic curve, which evaluates the strength development of concrete with maturity. According to the results, as W/C and compressive strength for protecting from frost damages at early ages increased, longer protecting duration is required. It shows that the protecting durations of FAC(Fly Ash Cement) are longer than those of OPC(Ordinary Portland Cement).

• Journal of Information Processing Systems
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• v.15 no.6
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• pp.1489-1502
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• 2019

This work introduces a novel unweighted combination method (UCSS) for business failure perdition (BFP). With considering features of BFP in the age of big data, UCSS integrates the quantitative and qualitative analysis by utilizing soft set theory (SS). We adopt the conventional expert system (ES) as the basic qualitative classifier, the logistic regression model (LR) and the support vector machine (SVM) as basic quantitative classifiers. Unlike other traditional combination methods, we employ soft set theory to integrate the results of each basic classifier without weighting. In this way, UCSS inherits the advantages of ES, LR, SVM, and SS. To verify the performance of UCSS, it is applied to real datasets. We adopt ES, LR, SVM, combination models utilizing the equal weight approach (CMEW), neural network algorithm (CMNN), rough set and D-S evidence theory (CMRD), and the receiver operating characteristic curve (ROC) and SS (CFBSS) as benchmarks. The superior performance of UCSS has been verified by the empirical experiments.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.107-108
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• 2012

The study on the strength prediction using Maturity is mainly focused on, but the study on the concrete mixing blast furnace slag powder is insufficient. The purpose of this study is to investigate the relationships between compressive strength and equivalent age by Maturity function and is to compare and examine the strength prediction of concrete mixing Blast Furnace Slag Power using ACI and Logistic Curve prediction equation. So it is intended that fundamental data are presented for quality management and process management of concrete mixing Blast Furnace Slag Power in the construction field.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.3
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• pp.200-207
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• 2013

This paper presents the mesh selectivity of a net pot for common octopus Octopus minor for the sustainable resources management of common octopus. The filed experiments were carried out the total 10 times in the southern part of coastal sea in Korea from March to May in 2010 using net pots of five different mesh sizes (16, 18, 20, 22 and 26mm). The test of size selectivity, indicated a 50% selection value on the logistic master curve of 3.195, whereby 50% of individuals with a mantle size of approximately 70.3mm selected a mesh size of 22mm. Considering that 50% of common octopus entering sexual maturity have a mantle size of 70.6mm, the optimum mesh size should be equal to, or larger than 22mm.

• Journal of the Korea institute for structural maintenance and inspection
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• v.3 no.2
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• pp.177-183
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• 1999

The major object of this study is to investigate experimentally the experimental equation by the non-destructive testing methods of ultrasonic pulse velocity, rebound number, combined method of ultrasonic pulse velocity and rebound number, maturity which are applicable to the evaluation of compressive strength of concrete at early ages. Also test result of mix are statistically analyzed to infer the correlation coefficient between the maturity and the compressive strength of concrete. The results show good application of Logistic curve for estimating strength development under various curing temperature. The relation between ultrasonic pulse velocity, rebound number, combined method of ultrasonic pulse velocity and rebound number and compressive strength of concrete have low correlation coefficient, but maturity method show good correlation coefficient.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.251-252
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• 2012

The exiting studies on the strength prediction by maturity method is mainly focused on concrete using OPC, meanwhile the study on the concrete mixing blast furnace slag powder (BFSP) is insufficient. The purpose of this study is to investigate the relationships between compressive strength and equivalent age by existing Maturity functions, i.e., Nurse-saul function Arrhenius function. This study also compared and examined the strength prediction of concrete mixing BGSP using ACI model and Logistic Curve prediction equation. Therefore, it is intended that fundamental data are presented for quality management and process management of concrete mixing BFSP.

• Journal of Animal Science and Technology
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• v.54 no.6
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• pp.395-400
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• 2012

This study was conducted to estimate the growth curve parameters for the body weight (BW) and body length (BL) of miniature pigs in Korea. Growth curve parameters were estimated through a nonlinear regression model using Gompertz, Logistic, and von Bertalanffy methods. A total of 25 piglets were measured monthly from birth up to 15 months of age to estimate both body weight and length. Results showed that the estimated average values for the body weight (body length) were 31.83 kg (58.77 cm) for the mature weight (A), 3.06 (1.74) for the growth ratio (${\beta}$), and 0.28 (0.52) for the maturing rate (${\kappa}$). Average inflection points showing maximum growth rate estimated each month for body weight were 3.97 kg and 11.70 cm, while for the body length were 1.06 kg and 21.61 cm. Moreover, the estimated maturation rates of the body weight and length for the group of Sire 1 were 0.22 and 0.40 respectively, whereas for the group of Sire 2 these values were 0.34 and 0.39. On the other hand, for the groups of Dam 1, Dam 2, and Dam 3, maturation rates for their body weights were 0.26, 0.28 and 0.33 respectively, while for their body lengths these values were 0.43, 0.37, and 0.38, respectively. The study also indicated a negative relationship between the values of mature weight and maturity rate for the body weight will result to a higher inflection point which is in contrast for the body length where results show that a positive relationship between the values of mature length and the maturity rate will result to a higher inflection point. Furthermore, the growth performance of miniature pig varies across stages but using these estimated growth curve parameters could improve the genetic traits of miniature pig.