• Journal of Korean Institute of Industrial Engineers
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• v.25 no.3
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• pp.393-403
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• 1999

In this research, a reach posture prediction based on a two-segment trunk model was made. Recently, reach posture prediction models have used inverse kinematics to provide a single posture that a person naturally takes, with a single segment trunk model that had some shortcomings. A two-segment trunk model was first developed with two links; pelvis link and lumbar-thoracic link. The former refers to the link from the hip joint to L5/S1 joint while the latter does the link from L5/S1 to the shoulder joint. Second, a reach prediction model was developed using the two-segment trunk model. As a result, more reliable equations for two-segment trunk motion were obtained, and the lean direction which refers to the movement direction of the trunk was not found to have a significant effect on the two-segment trunk motion. The results also showed that the hip joint is more preferred over L5/S1 to serve as a reference point for trunk models and the reach prediction model being developed predicted the real posture accurately.

• The Journal of Korea Robotics Society
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• v.6 no.3
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• pp.230-236
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• 2011

In previous researches, the self-stability was studied for the spring-mass model and the two segment leg model. In these researches, it was presented that the spring-mass model has the self-stable region at relatively high speed running and the two segment leg model has the self-stable region at relatively low speed running. If the model was run in the self-stable region, the cost of transport is zero ideally. That is, actually, only the energy loss is needed to compensate for running. This means that the energy efficiency is high, running in the self-stable region. We want to have high energy efficiency at low and high speed running. So, in this paper, we propose the design direction of the three segment leg having the self-stable region at low and high speed running. And we prove the self-stable region of the three segment leg designed by the proposed design direction.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.12
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• pp.1541-1547
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• 1988

In this paper, a new model for isolated word recognition called segment probability model is proposed. The proposed model is composed of two procedures of segmentation and modelling each segment. Therefore the spoken word is devided into arbitrary segments and observation probability in each segments is obtained using vector quantization. The proposed model is compared with pattern matching method and hidden Markov model by recognition experiment. The experimental results show that the proposed model is better than exsisting methods in terms of recognition rate and caculation amounts.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.757-762
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• 2007

The lining segment which is the main structure of the shield tunnel consists of joints, not continua. Past international and domestic design data have been commonly used for design practices without specific verification about the structural analysis model, design load, and affection of the soil constant of the lining segment. In this study, the propriety is estimated through the comparison between analytical solution and numerical solution for segment analysis and design models of the shield tunnel which is being used internationally and domestically. As a result, the full. circumferential beam jointed spring model (1R-S0) is suggested by considering aspects of convenient use, application to field condition, and accuracy of analysis result. With suggested model, the parameter analysis was conducted for joint stiffness, ground rigidity, joint distribution, and joint number.

• Korean Journal of Computational Design and Engineering
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• v.16 no.6
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• pp.424-436
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• 2011

In this paper, we propose a methodology of generating a parametric segment model for human body using the Korean anthropometric data. The model is defined as an articulated body model consisted with 19 ellipsoid primitives. The primitives are joined at locations representing the physical joints of human body. A lot of previous researches have suggested methodologies of generating body models using the European or American anthropometric data, so that these models were inappropriate for engineering analyses and simulations in case of the Koreans. We defined a set of 35 body dimensions representing our segment model based on the anthropometric data of Koreans. Also we defined four key parameters of age, height, weight and waist circumference, and then we applied regression equations to associate the parameters to the aforementioned dimensions. As the results, we obtained the parametric human body segment models according to the various body types and the subject-specific models for a specific individual. The models in the various industries can be used as the base models for static and dynamic analysis considering the Koreans.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.10
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• pp.1486-1492
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• 2015

The following study carried out the characteristic analysis based on the magnet segment of Interior Permanent Magnet Synchronous Motor(IPMSM) for the urban railway vehicles. IPMSM affects the electromagnetic characteristics through the change in magnetic flux based on the rotor structure, and significantly influences the structural features through the change of pressure. Therefore, satisfied by the demanded traction force of the IPMSM, magnet segment derived three different model types. The 1-segment PM model consisted an undivided permanent magnet. The 2-Bridge model consisted a divided permanent magnet with the application of Bridge. The 3-Bridge model consisted additional dividing with one more Bridge applied. The electromagnetic characteristics of the three models were compared and analyzed along with the structural features regarding the scattering of permanent magnet based on strong centrifugal force from the rotation of the rotor at high speed. In conclusion, the final model with electromagnetic characteristics and structural features most suitable of IPMSM for the urban railway vehicles was derived, and the effectiveness was verified through the characteristic experiments after the production of the derived model.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.11
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• pp.188-193
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• 2003

To predict changes in biomechanical parameters such as intradiscal pressure, and the shock absorbing mechanism in the spinal motion segment under different impact duration/loading rates, a three dimensional L3/L4 motion segment finite element model was modified to incorporate the poroelastic properties of the motion segment. The results were analyzed under variable impact duration for normal and degenerated discs. For short impact duration and a given maximum compressive force, relatively high cancellous pore pressure was generated as compared with a case of long impact duration, although the amount of impulse was increased. In contrast relatively constant pore pressure was generated in the nucleus. Disc degeneration increased pore pressure in the disc and decreased pore pressure in the cancellous core, which is more vulnerable to compressive fracture compared with intact case.

• Proceedings of the KAIS Fall Conference
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• 2003.06a
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• pp.328-330
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• 2003

A surface equation of state for globular proteins at air-water interface accounting for the molecular structure, segment-segment, segment-solvent, and electrostatic interactions was proposed and compared to C-14 isotope experiments. This lattice model comprised a simplifying assumption that all adsorbed segments are in the form of trains. The number of segment adsorbed per molecule in case of bovine serum albumin linearly depended on the surface concentration whereas the lysozyme segments adsorbed at the interface were independent of surface concentration. The segment-solvent(water) interaction for both of proteins were found to be unfavorable owing to the proteins unfolding. From comparison of model computation and experimental data, BSA unfolded more than lysozyne because of the larger surface area of contact.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.2
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• pp.179-194
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• 2017

The segment lining design for shield tunnel is generally carried out by using the beam-spring model and the induced member forces from the model are strongly influenced by the components of the model such as imposed load, coefficient of subgrade reaction, location of segment joint and its stiffness. The structural models and stiffness of its connection part found used in abroad design cases is usually obtained as it is for the domestic design of segment of shield tunnel. Those models and stiffness in existing design cases are conventionally applied to a new tunnel design without any suitability review for the project. In this study, the application method of base components of the model such as the coefficient of subgrade reaction and modelling method to the segment lining design was suggested by carrying out the comparative study of the base elements for the member forces estimation of segment lining of shield tunnel.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.1
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• pp.16-37
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• 2022

Accurate liver segment segmentation based on radiological images is indispensable for the preoperative analysis of liver tumor resection surgery. However, most of the existing segmentation methods are not feasible to be used directly for this task due to the challenge of exact edge prediction with some tiny and slender vessels as its clinical segmentation criterion. To address this problem, we propose a novel deep learning based segmentation model, called Boundary-Aware Dual Attention Liver Segment Segmentation Model (BADA). This model can improve the segmentation accuracy of liver segments with enhancing the edges including the vessels serving as segment boundaries. In our model, the dual gated attention is proposed, which composes of a spatial attention module and a semantic attention module. The spatial attention module enhances the weights of key edge regions by concerning about the salient intensity changes, while the semantic attention amplifies the contribution of filters that can extract more discriminative feature information by weighting the significant convolution channels. Simultaneously, we build a dataset of liver segments including 59 clinic cases with dynamically contrast enhanced MRI(Magnetic Resonance Imaging) of portal vein stage, which annotated by several professional radiologists. Comparing with several state-of-the-art methods and baseline segmentation methods, we achieve the best results on this clinic liver segment segmentation dataset, where Mean Dice, Mean Sensitivity and Mean Positive Predicted Value reach 89.01%, 87.71% and 90.67%, respectively.