• Advances in Computational Design
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• v.5 no.3
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• pp.305-321
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• 2020

In this paper is presented the solution method for three-dimensional problem of transversely isotropic body's elastoplastic deformation by the finite element method (FEM). The process of problem solution consists of: determining the effective parameters of a transversely isotropic medium; construction of the finite element mesh of the body configuration, including the determination of the local minimum value of the tape width of non-zero coefficients of equation systems by using of front method; constructing of the stiffness matrix coefficients and load vector node components of the equation for an individual finite element's state according to the theory of small elastoplastic deformations for a transversely isotropic medium; the formation of a resolving symmetric-tape system of equations by summing of all state equations coefficients summing of all finite elements; solution of the system of symmetric-tape equations systems by means of the square root method; calculation of the body's elastoplastic stress-strain state by performing the iterative process of the initial stress method. For each problem solution stage, effective computational algorithms have been developed that reduce computational operations number by modifying existing solution methods and taking into account the matrix coefficients structure. As an example it is given, the problem solution of fibrous composite straining in the form of a rectangle with a system of circular holes.

• Smart Structures and Systems
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• v.3 no.4
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• pp.423-437
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• 2007

The empirical mode decomposition (EMD) method is well-known for its ability to decompose a multi-component signal into a set of intrinsic mode functions (IMFs). The method uses a sifting process in which local extrema of a signal are identified and followed by a spline fitting approximation for decomposition. This method provides an effective and robust approach for decomposing nonlinear and non-stationary signals. On the other hand, the IMF components do not automatically guarantee a well-defined physical meaning hence it is necessary to validate the IMF components carefully prior to any further processing and interpretation. In this paper, an attempt to use the EMD method to identify properties of nonlinear elastic multi-degree-of-freedom structures is explored. It is first shown that the IMF components of the displacement and velocity responses of a nonlinear elastic structure are numerically close to the nonlinear normal mode (NNM) responses obtained from two-dimensional invariant manifolds. The IMF components can then be used in the context of the NNM method to estimate the properties of the nonlinear elastic structure. A two-degree-of-freedom shear-beam building model is used as an example to illustrate the proposed technique. Numerical results show that combining the EMD and the NNM method provides a possible means for obtaining nonlinear properties in a structure.

• The Korean Journal of Pain
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• v.1 no.2
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• pp.199-202
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• 1988

Secure fixation is essential for continous epidural catheterization on a long-term-basis. Adhesive tape or surgical knots were commonly used for those patients, but the surgical knot method has a tendency to cause strangulation of catheter. Another invasive technique, subcutaneous tissue tunnelling is more safe than other methods but requires sophisticated technique and time. We employed a simple device using a blood transfusion set for patients who have epidural catheters placed safely un their backs. In 120 patients treated for postoperative and chronic pain by means of this technique, the results were as follows: 1) Five of 120 patients (4.2%) developed backache and pruritus, but there were no instances of respiratory depression, local infection and headache. 2) Nine of 120 patients (7.5%) failed booster-injections, but two cases were due to be non-technical errors. 3) The duration of fixation was 1~3 days in most cases (85%), the longest being for 21 days.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.5
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• pp.2555-2575
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• 2017

This paper presents a dual exposure fusion method for image enhancement. Images taken with a short exposure time usually contain a sharp structure, but they are dark and are prone to be contaminated by noise. In contrast, long-exposure images are bright and noise-free, but usually suffer from blurring artifacts. Thus, we fuse the dual exposures to generate an enhanced image that is well-exposed, noise-free, and blur-free. To this end, we present a new scale-space patch-match method to find correspondences between the short and long exposures so that proper color components can be combined within a proposed dual non-local (DNL) means framework. We also present a residual filtering method that eliminates the structure component in the estimated noise image in order to obtain a sharper and further enhanced image. To this end, the entropy is utilized to determine the proper size of the filtering window. Experimental results show that our method generates ghost-free, noise-free, and blur-free enhanced images from the short and long exposure pairs for various dynamic scenes.

• Journal of Information Technology Services
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• v.5 no.3
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• pp.173-186
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• 2006

The local public organizations, to secure the Confidentiality, Integrity, Authentication and Non-Repudiation of cyber administrative environment is giving it a try to consolidate the official documents among them by standardizing all the documents into XML formats together with the establishment of the GPKI(Government Public Key Infrastructure). The Authentication System based on the PKI(Public Key Infrastructure) used by the GPKI, however, provides only the simple User Authentication and thus it results in the difficulty in managing the position, task, role information of various users required under the applied task environment of public organizations. It also has a limitation of not supporting the detailed access control with respect to the XML-based public documents.In order to solve these issues, this study has analyzed the security problems of Authentication and access control system used by the public organizations and has drawn the means of troubleshoot based on the analysis results through the scenario and most importantly it suggests the access control model applied with PMI and SAML and XACML to solve the located problem.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.7
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• pp.3620-3637
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• 2019

Since the birth of Synthetic Aperture Radar (SAR), it has been widely used in the military field and so on. However, the existence of speckle noise makes a good deal inconvenience for the subsequent image processing. The continuous development of sparse representation (SR) opens a new field for the speckle suppressing of SAR image. Although the SR de-noising may be effective, the over-smooth phenomenon still has bad influence on the integrity of the image information. In this paper, one novel SAR image de-noising method based on residual image fusion and sparse representation is proposed. Firstly we can get the similar block groups by the non-local similar block matching method (NLS-BM). Then SR de-noising based on the adaptive K-means singular value decomposition (K-SVD) is adopted to obtain the initial de-noised image and residual image. The residual image is processed by Shearlet transform (ST), and the corresponding de-noising methods are applied on it. Finally, in ST domain the low-frequency and high-frequency components of the initial de-noised and residual image are fused respectively by relevant fusion rules. The final de-noised image can be recovered by inverse ST. Experimental results show the proposed method can not only suppress the speckle effectively, but also save more details and other useful information of the original SAR image, which could provide more authentic and credible records for the follow-up image processing.

• Journal of Industrial Technology
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• v.43 no.1
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• pp.7-13
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• 2023

Nowadays, traffic congestion is emerging as a major problem due to the rapid population growth and the increase in automobiles. The train is a convenient means of transportation that can efficiently solve these problems. Trains have been developed in line with human aspirations for a long time, but research on safety is still insufficient. This study aims to check safety by conducting static tests and fatigue tests on bogie frames, and to help develop bogie frames in the future. For the static test, a strain gauge was attached to the point where the local stress concentration was expected beforehand, and the result value was derived, compared with existing theories, and expressed as a Goodman diagram. In the fatigue test, a total of 10 million loads were applied over three stages, and no cracks appeared in the non-destructive test conducted after each stage. Both tests were conducted according to the strict test method of the bogie frame presented by the UIC Code. It satisfied both fatigue life and strength evaluation criteria and was judged to be a bogie frame usable for safe train production.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.3
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• pp.639-647
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• 2011

In this paper, we introduce a design methodology of data-centroid Radial Basis Function neural networks with extended polynomial function. The two underlying design mechanisms of such networks involve K-means clustering method and Particle Swarm Optimization(PSO). The proposed algorithm is based on K-means clustering method for efficient processing of data and the optimization of model was carried out using PSO. In this paper, as the connection weight of RBF neural networks, we are able to use four types of polynomials such as simplified, linear, quadratic, and modified quadratic. Using K-means clustering, the center values of Gaussian function as activation function are selected. And the PSO-based RBF neural networks results in a structurally optimized structure and comes with a higher level of flexibility than the one encountered in the conventional RBF neural networks. The PSO-based design procedure being applied at each node of RBF neural networks leads to the selection of preferred parameters with specific local characteristics (such as the number of input variables, a specific set of input variables, and the distribution constant value in activation function) available within the RBF neural networks. To evaluate the performance of the proposed data-centroid RBF neural network with extended polynomial function, the model is experimented with using the nonlinear process data(2-Dimensional synthetic data and Mackey-Glass time series process data) and the Machine Learning dataset(NOx emission process data in gas turbine plant, Automobile Miles per Gallon(MPG) data, and Boston housing data). For the characteristic analysis of the given entire dataset with non-linearity as well as the efficient construction and evaluation of the dynamic network model, the partition of the given entire dataset distinguishes between two cases of Division I(training dataset and testing dataset) and Division II(training dataset, validation dataset, and testing dataset). A comparative analysis shows that the proposed RBF neural networks produces model with higher accuracy as well as more superb predictive capability than other intelligent models presented previously.

• Journal of Korean Society of Forest Science
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• v.105 no.3
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• pp.366-376
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• 2016

The "Forest Partnership" mechanism in Indonesia allows those with authority to manage forests, including Forest Management Units (KPH) and concession holders, to partner with local communities for forest management and profit sharing. The objective of this study is to identify the challenges that this new mechanism is facing and develop practical policy recommendations for its successful implementation. "Lombok Forest Partnership" is the first of its kind in Indonesia between Forest Management Unit (KPH) and a local community. The local community members participating in this partnership were surveyed for their expected outcomes, degree of their satisfaction about the process and profits sharing, as well as other factors affecting their participation. Respondents reported that they have obtained the information on Forest Partnership completely from KPH and NGO. Local peoples participated in Lombok Forest Partnership to improve their incomes, and recognized timber production as the most important income source with high possibility of success. However, timber production will require sizable initial capital investment for establishing nursery and other supporting activities, which cannot come from local communities lacking economic means. Thus, Forest Partnership would be difficult to succeed if KPH does not take the initiative to permit and promote local community to use special area and generate profits in their jurisdiction. KPH, in turn, can share the profits with local peoples. In this regard, KPH's leadership is the key factor in the success of Forest Partnership. However, KPH will need to cultivate their capacity to develop and implement income-generating business with local community. Although profit sharing ratio of timber and non-timber forest products among local community who participated in Lombok Forest Partnership was very high at 75%, and 90%, the level of satisfaction on profit sharing ratio was only average. The cooperative organized by the local community is also dealing with sensitive nature of allocating forest area internally among their members. Thus, keeping the principle of fairness, equity and transparency is the key for successful implementation of Forest Partnership mechanism. This first case of Forest Partnership can serve as a model for the future cases and provide the early lessons.

• Journal of the Economic Geographical Society of Korea
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• v.20 no.1
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• pp.105-120
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• 2017

Chung-ju enterprise city was selected as a model enterprise city in 2005, and the city is planned to finish the construction in 2020. The main purpose of this study is to suggest the developing strategy and activation plan for Chung-ju enterprise city based on the enterprise city of developed countries. Chung-ju enterprise city will grow into well-being self-sufficient city due to the cutting edge knowledge, industry-centered cluster which is the new growth industry of Chungchungbuk-do and the surrounding excellent nature. For the success of Chung-ju enterprise city, the cooperation between developing agents such as companies, universities, local government, and central government is important. The leading companies and researching facilities should be attracted as well. Also, non-profit exclusive organization must be installed. The successful development of Chung-ju enterprise city means the success of balanced region development policy which will solve overpopulation of capital region and unbalance of Korea.