• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1998.10a
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• pp.285-291
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• 1998

A hydraulic pin-on-disk type tribotester was developed and it's performance was investigated experimentally. The estimate of the performance was accomplished by comparing those of the pneumatic and the dead-weight loading method. The reliability to the performance was conformed. By hydraulic loading method more accra'ate friction coefficient could be got.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1998.10a
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• pp.175-180
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• 1998

In container crane system, the variation of cargo weight have effect on the travelling and sway control of load. For precise travelling and/or anti-sway control of crane system, the cargo weight should be measured and considered with control algorithm. But, and added attachment for measuring the cargo weight put restraint upon the control freedom for travelling and anti-sway. In this paper, we propose an estimation method for cargo weight in container crane system by using observation technique. First of all, we model the container crane system as a bilinear system and transform this model into linear system with external disturbance model. Second, we propose a generalized type - disturbance estimation observer and set a disturbance model, where, the cargo weight is related with the sway of load, and the sway is represented as a periodic external disturbance. Lastly, by using simulation we verify that the proposed algorithm of disturbance estimation observer is effective to estimate the cargo weight, and it will be used with anti-sway control algorithm.

• Journal of Biosystems Engineering
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• v.29 no.3
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• pp.275-280
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• 2004

The main objective of this study was to develop and evaluate a model for estimating pigs weight using computer vision for improving the management in Korean swine farms in Korea. This research was carried out in two steps: 1) to find a model that relates the projection area with the weight of a pig; 2) to implement the model in a computer vision system mainly consisted of a monochrome CCD camera, a frame grabber and a computer system for estimating the weight of pigs in a non-contact, real-time manner. The model was developed under an important assumption there were no observable genetic differences among the pigs. The main results were: 1) The relationship between the projection area and the weight of pigs was W = 0.0569 ${\times}$ A - 32.585($R^2$ = 0.953), where W is the weight in kg; A is the projection area of a pig in $\textrm{cm}^2$; 2) The model could estimate the weight of pigs with an error less than 3.5%.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.5
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• pp.100-112
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• 2011

This paper studied on a theoretical approach to predict structural performances and weight -reduction rates of hybrid bodyshells in case that the material of underframe structure is substituted. To choose other light-weight materials to be substituted for the original underframe material, compressive, bending and twisting deformations are considered under constant stiffness and strength conditions, which derive some new weight-reduction indices from a structural performance point of view. Next, these weight-reduction indices were verified using the finite element analyses of some simplified examples. It is shown that the derived indices to estimate the weight-reduction can be utilized as a good criterion for material substitution of the underframe at a basic design stage.

• 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.

• Journal of Bio-Environment Control
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• v.25 no.3
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• pp.146-152
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• 2016

Due to complicate canopy structures of Irwin mangoes grown in greenhouses, it is difficult to determine their growth parameters accurately. Leaf area, leaf fresh weight, and leaf dry weight are widely used as indicators to diagnose the tree growth. Therefore, it is necessary to establish models that can non-destructively estimate these growth indicators. The objective of this study was to establish regression models to estimate leaf area, leaf fresh weight, and leaf dry weight of Irwin mangoes (Mangifera indica L. cv. Irwin) by using leaf length, leaf width, petiole length, and SPAD value. The input values of leaf length, leaf width, petiole length, and SPAD value of 6-year old Irwin mangoes were measured, and the corresponding output values of leaf area, leaf fresh weight, and leaf dry weight were also measured. After 14 models were selected among the existing models, coefficients of the models were estimated by regression analysis. Three models with higher $R^2$ and lower RMSE values selected. In validation the $R^2$ values for the selected models were 0.967, 0.743, and 0.567 in the leaf area, leaf fresh weight, and leaf dry weight models, respectively. It is concluded that this models will be helpful to conveniently diagnose the growth of the Irwin mango.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.2
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• pp.143-148
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• 1990

An experiment was conducted to compare the traditional weigh-suckle-weigh method and the $D_2O$ dilution technique to estimate milk consumption of suckling piglets. Milk consumption of 50 individual piglets was estimated on four consecutive days by the $D_2O$ dilution method and for approximately 8 hours on both the second and fourth day by the traditional WSW method. The average milk intake of piglets estimated by the $D_2O$ dilution method was 45.0 g/hr and there were no significant differences between the four measurement period. The traditional weigh-suckle-weigh method provided a significantly lower estimate of milk consumption (36.8 g/hr). However correction for weight losses associated with milk suckling and weighing would increase the weigh-suckle-weigh estimate to a level similar to that determined by the $D_2O$ dilution method.

• Korean Journal of Poultry Science
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• v.25 no.1
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• pp.11-19
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• 1998

This study was conducted to estimate the heritabilities and genetic correlations on egg weight and egg compositional traits for breeding plan and selection in Korean native chicken. Data analyzed were the records of 46,908 eggs from 430 layers produced from 180 dam and 26 sire families, from April, 1994 to September, 1995. On egg weight and egg compositional traits at 1st egg, 300 and 500 days of age, the egg weights were 41.489, 49.544 and 52.770g ; the albumin weights were 25.953, 29.979 and 31.288g; the yolk weights were 11.091, 14.541 and 16.368g; shell weights were 4.472, 5.037 and 5.099g, respectively. The estimates of heritability of egg weights and egg compositional traits based on the variance of sires, dams and combined components at 300 days of age were 0.214, 0.226 and 0.720 for egg weight ; 0.307, 0.152 and 0.730 for albumin weight ; 0.124, 0.953 and 0.699 for yolk weight ; 0.047, 0.026 and 0.536 for shell weight. The genetic correlation coefficient between egg weight and albumen weight was 0.083~0.951 ; 0.310~0.507 between egg weight and yolk weight ; 0.242~0.523 between egg weight and shell weight ; 0. 237~0. 413 between albumen weight and yolk weight ; 0.232~0.449 between albumen weight and shell weight ; -0.264~0.239 between yolk weight and shell weight, respectively.

• International Journal of Automotive Technology
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• v.4 no.4
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• pp.203-211
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• 2003

This paper describes a method for a falling weight impact test to estimate the impact energy absorbing characteristics and impact strength of CFRP (Carbon-fiber reinforced plastics) laminate plates based on considerations of stress wave propagation theory, which were converted to measurements of load and displacement verses time. The delamination area of impacted specimens for the different ply orientations was measured with an ultrasonic C-scanner to determine the correlation between impact energy and delamination area. The energy absorbed by a quasi-isotropic specimen having four interfaces was higher than that of orthotropic laminates with two interfaces. The more interfaces, the greater the energy absorbed. The absorbed energy of a hybrid specimen embedding GFRP (Glass-fiber reinforced plastics) layer was higher than that of normal specimens. Also, a falling weight impact tester was built to evaluate the characteristics and impact strength of CFRPs.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.430-433
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• 2005

In this study, weight of evidence(WOE) technique based on the bayesian method was applied to estimate the groundwater yield characteristics in the Pocheon area in Kyungki-do. The ground water preservation depends on many hydrogeologic factors that include hydrologic data, landuse data, topographic data, geological map and other natural materials, even with man-made things. All these data can be digitally collected and managed by GIS database. In the applied technique of WOE, The prior probabilities were estimated as the factors that affect the yield on lineament, geology, drainage pattern or river system density, landuse and soil. We calculated the value of the Weight W+, W- of each factor and estimated the contrast value of it. Results by the ground water yield characteristic calculations were presented in the form of posterior probability map to the consideration of in-situ samples. It is concluded that this technique is regarded as one of the effective technique for the feasibility mapping related to detection of groundwater bearing zones and its spatial pattern.