• Structural Engineering and Mechanics
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• v.71 no.3
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• pp.317-327
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• 2019

The aim of this paper is to present the most important issues on the implementation, operation and maintenance of foundation for machines. The article presents the newest solutions both in terms of technology implementation as well as materials used in construction of such structures. Foundations for machines are special building structures used to transfer loads from an operating machine to the subsoil. The purpose of these foundations is not just to transfer loads, but also to reduce vibrations occurring during operation of the machine, i.e. their damping and preventing redistribution to other elements of the building. It should be noted that foundations for machines (particularly foundations for hammers) are the most dynamically loaded building structures. For these reasons, they require precise static and dynamic calculations, accuracy in their implementation and care for them after they have been made. Therefore, the paper in detail present the guidelines regarding: design, construction and maintenance of structures of this type. Furthermore, the most important parameters and characteristics of materials used for the construction of these foundations are described. As a result of the conducted analyzes, it was found that the concrete mix, in foundations for machines, should have a low water/binder ratio. For its execution, it is necessary to use broken aggregates from igneous rocks and binders modified with mineral additives and chemical admixtures. On the other hand, the reinforcement of composites should contain a large amount of structural reinforcement to prevent shrinkage cracks.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.10a
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• pp.455-462
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• 1998

Analysis and design of vibrating machine foundations subjected to dynamic loads is a very complex problem. Thus it is difficult to set up an accurate analytical modeling. Generally, the design of foundations for vibrating machines has been performed by the equivalent static analysis which is generally based on engineer's experience and various assumptions The purpose of this study is to develop an integrated system which enables structural engineers to produce results of high quality within a short time in works related to structural analysis and design of foundation for vibrating machines. As the result of this study, level-up of application software is expected as well as improvement of quality in structural engineering and reduction of engineers' effort.

• Journal for History of Mathematics
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• v.22 no.3
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• pp.31-44
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• 2009

Anyone wishing to understand cognitive science, a converging science, need to become familiar with three major mathematical landmarks: Turing machines, Neural networks, and $G\ddot{o}del's$ incompleteness theorems. The present paper aims to explore the mathematical foundations of cognitive science, focusing especially on these historical landmarks. We begin by considering cognitive science as a metamathematics. The following parts addresses two mathematical models for cognitive systems; Turing machines as the computer system and Neural networks as the brain system. The last part investigates $G\ddot{o}del's$ achievements in cognitive science and its implications for the future of cognitive science.

• Geomechanics and Engineering
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• v.1 no.2
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• pp.121-142
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• 2009

The paper deals with the applications of spectral finite element method to the dynamic analysis of framed foundations supporting high speed machines. Comparative performance of approximate dynamic stiffness methods formulated using static stiffness and lumped or consistent or average mass matrices with the exact spectral finite element for a three dimensional Euler-Bernoulli beam element is presented. The convergence of response computed using mode superposition method with the appropriate dynamic stiffness method as the number of modes increase is illustrated. Frequency proportional discretisation level required for mode superposition and approximate dynamic stiffness methods is outlined. It is reiterated that the results of exact dynamic stiffness method are invariant with reference to the discretisation level. The Eigen-frequencies of the system are evaluated using William-Wittrick algorithm and Sturm number generation in the $LDL^T$ decomposition of the real part of the dynamic stiffness matrix, as they cannot be explicitly evaluated. Major's method for dynamic analysis of machine supporting structures is modified and the plane frames are replaced with springs of exact dynamic stiffness and dynamically flexible longitudinal frames. Results of the analysis are compared with exact values. The possible simplifications that could be introduced for a typical machine induced excitation on a framed structure are illustrated and the developed program is modified to account for dynamic constraint equations with a master slave degree of freedom (DOF) option.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.13 no.4
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• pp.281-289
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• 2003

Recently, as high-rise buildings increase steeply, sub-structures of them are often supported on in-homogeneous foundation. And there are many machines in sub-structures of buildings, and slabs of sub-structures are affected by vibration which they make. This paper deals with vibration of plates with concentrated masses on in-homogeneous foundation. Machines on plates are considered as concentrated masses. In-homogeneous foundation is considered as assigning $k_{w1}$ and $k_{w2}$ to Winkler foundation parameters of central region and side region of plate respectively, and foundation is idealized to use Pasternak foundation model which considered both of Winkler foundation parameter and shear foundation parameter. In this paper, applying Winkler foundation parameters which $k_{w1}$and $k_{w2}$ are 10, $10^2$, $10^3$ and shear foundation parameter which are 10, 20 respectively, first natural frequencies of thick plates with concentrated masses on in-homogeneous foundations are calculated.

• Advances in aircraft and spacecraft science
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• v.9 no.1
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• pp.59-68
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• 2022

The physical and mathematical foundations of the heat-shielding composite materials functioning under the conditions of aerodynamic heating of aircraft, as well as under the conditions of the point effect of high-energy radiation are considered. The problem of deformation of a thin shallow shell under the action of a local temperature field is approximately solved. Such problems arise, for example, in the case of local destruction of heat-protective coatings of aircraft shells. Then the aerodynamic heating acts directly on the load-bearing shell of the structure. Its destruction inevitably leads to the death of the entire aircraft. A methodology has been developed for the numerical solution of the entire complex problem on the basis of economical absolutely stable numerical methods. Multiple results of numerical simulation of the thermal state of the locally heated shallow shell under conditions of its thermal destruction at high temperatures have been obtained.

• Journal of the Korean Society for Library and Information Science
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• v.50 no.2
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• pp.309-336
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• 2016

This paper introduces a relation extraction system that can be used in identifying and classifying semantic relations between biomedical entities in scientific texts using machine learning methods such as Support Vector Machines (SVM). The suggested system includes many useful functions capable of extracting various linguistic features from sentences having a pair of biomedical entities and applying them into training relation extraction models for maximizing their performance. Three globally representative collections in biomedical domains were used in the experiments which demonstrate its superiority in various biomedical domains. As a result, it is most likely that the intensive experimental study conducted in this paper will provide meaningful foundations for research on bio-text analysis based on machine learning.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.2
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• pp.335-341
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• 1994

Laboratory model test results for bearing capacity of a square shallow foundation supported by a sand layer reinforced with layers of geogrid have been presented. Use of geogrids provides an economical and time efficient method for improving load-settlement, and strength characteristics of weak soils. Especially the geogrid reinforced soil will be necessary in the case of foundations supporting machines, embankments for railroads, and foundations of structures in earthquake-prone areas. Based on the present model test results, the bearing capacity ratio (BCR) with respect to the ultimate bearing capacity (UBC), at levels of limited settlement of the shallow foundation. has been determined. Also, it appears that significant improvement in the UBC of medium sands can be achieved by reinforcing elements which shows promise for future work.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.4
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• pp.933-939
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• 1994

This paper has primarily been directed to evaluate the beneficial effects of geogrid reinforcement in a medium sand on the ultimate bearing capacity (UBC) of a surface foundation. Also, this study was conducted to investigate the permanent settlement of a shallow square foundation in improving the cyclic load-settlement characteristics of reinforced sand deposits by conducting a series of laboratory model tests. Use of geogrids provides an economical and time efficient method for improving load-settlement and strength characteristics of weak soils. Especially the geogrid reinforced soil will be necessary in the case of foundation supporting machines, embankments for railroads, and foundations of structures in earthquake-prone areas. Finally, the test results indicate that the use of geogrid reinforcement in sand subgrades improves their performance under dynamic loads which shows promise for future work.

• Journal of the Korea Fashion and Costume Design Association
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• v.10 no.1
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• pp.45-53
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• 2008

Different method of textile fabrication had existed since the ancient times, but the most dominant form was the 'weaving' method which embodies the cross fabrication of vertical and horizontal threads using special weaving machines (looms). In addition, fabrication methods like knitting, felt, and lace were commonly practiced while intertwinement methods like twisting, braiding, and knotting techniques were frequently used for weaving strings and braid type textiles. In the past, people did not pay attention to strings and braids because they were classified as non-textiles, but, in this paper, we have expanded the scope of definition of textile to include strings and braids, and seek to conduct in-depth research on various different intertwinement of textiles. The adaptation of intertwinement method in arts and crafts enables limitless creative works reflecting the ever-changing taste and style of the creator. This creativity is further broadened by the fact that intertwinement methods encompass no set patterns and the subject and shape of its creation is as broad as its artistic pursuits. We can infer the knowledge of our ancestors, their aesthetic taste, and the pattern of life from these creations. In addition, these creations can provide comfort and improve the quality of life of modem people who are deeply deprived of sentimental and emotional solitude in the technological civilization of the 21stcentury. The main purpose of this paper is to examine traditional Korean arts and crafts made using the intertwinement methodology through the context of strings, braids, straw crafts and knotting method. Then it will conduct through research on the different materials, forms, characteristics, usage and other key notions based on the currently preserved records and relics to contribute to the research on traditional textiles and provide the foundations to the development of the Korean culture and cultural products, reflecting the true sole and aesthetics of traditional Korean textile crafts.