• 한국안전학회지
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• 제36권2호
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• pp.49-57
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• 2021

In the case of military supplies, any potential failure and causes of failures must be considered. This study is aimed at examining the failure modes of a rotorcraft landing system to identify the priority items. Failure mode and effects analysis (FMEA) is applied to the rotorcraft landing system. In general, the FMEA is used to evaluate the reliability in engineering fields. Three elements, specifically, the severity, occurrence, and detectability are used to evaluate the failure modes. The risk priority number (RPN) can be obtained by multiplying the scores or the risk levels pertaining to severity, occurrence, and detectability. In this study, different weights of the three elements are considered for the RPN assessment to implement the FMEA. Furthermore, the FMEA is implemented using a fuzzy rule base, similarity aggregation model (SAM), and grey theory model (GTM) to perform a comparative analysis. The same input data are used for all models to enable a fair comparison. The FMEA is applied to military supplies by considering methodological issues. In general, the fuzzy theory is based on a hypothesis regarding the likelihood of the conversion of the crisp value to the fuzzy input. Fuzzy FMEA is the basic method to obtain the fuzzy RPN. The three elements of the FMEA are used as five linguistic terms. The membership functions as triangular fuzzy sets are the simplest models defined by the three elements. In addition, a fuzzy set is described using a membership function mapping the elements to the intervals 0 and 1. The fuzzy rule base is designed to identify the failure modes according to the expert knowledge. The IF-THEN criterion of the fuzzy rule base is formulated to convert a fuzzy input into a fuzzy output. The total number of rules is 125 in the fuzzy rule base. The SAM expresses the judgment corresponding to the individual experiences of the experts performing FMEA as weights. Implementing the SAM is of significance when operating fuzzy sets regarding the expert opinion and can confirm the concurrence of expert opinion. The GTM can perform defuzzification to obtain a crisp value from a fuzzy membership function and determine the priorities by considering the degree of relation and the form of a matrix and weights for the severity, occurrence, and detectability. The proposed models prioritize the failure modes of the rotorcraft landing system. The conventional FMEA and fuzzy rule base can set the same priorities. SAM and GTM can set different priorities with objectivity through weight setting.

• Educational Technology International
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• 제11권1호
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• pp.27-46
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• 2010

The purpose of this paper is to apply the newly developed SICAT teaching and learning model to the actual scene of teaching and learning and draw a point of discussion for utilizing teaching and learning model, by uncovering the satisfaction of students and the inhibiting/facilitating elements when using the model. SICAT(Scientific Inquiry and Creative Activity with Technology; from here on SICAT), a teaching and learning model custom-built for engineering education, was developed, as more and more people paid attention to the demand for creative engineers. It was developed from the basis of PBL(Problem Based Learning), includes three sub-types which can be applied to the actual theory, design, and experimentation fields within engineering education. The three sub-types, which are ARDA(Analysis-Reasoning Activity & Discussion-Argumentation Activity), CoCD (Collaboration Activity & Capstone Design Activity), and ReSh(Reflection Activity & Sharing Activity), respectively support deductive and argumentation activities, creative design and collaboration activities, and retrospection and sharing activities. However, no research has been conducted to investigate whether or not there are inhibiting or facilitating elements in the application procedure, or what the rate of satisfaction for students is, when applying the SICAT model, which was newly developed to innovate existing engineering education, to the actual site of teaching and learning. Therefore, this research applied three types of SICAT teaching and learning models to the theory, design, and experimentation classes at the department of materials science and engineering at Hanyang University for eight weeks. After application, the students, teachers and tutors were surveyed and interviewed, and then the results analyzed in order to uncover inhibiting/facilitating elements and the rate of satisfaction. The satisfaction rate of students from the SICAT teaching and learning model was 3.78(in a perfect score of 5: The A type-3.65, The C type-3.80, The R type-3.90), and inhibiting/facilitating elements were drawn from the aspects of learning activities, support system. In conclusion, they can be contributed for implications of SICAT teaching and learning model universal use at engineering education in University.

• 한국지능시스템학회논문지
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• 제15권3호
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• pp.343-348
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• 2005

This paper describes an automatic finite element (FE) mesh generation for three-dimensional structures consisting of free-form surfaces. This mesh generation process consists of three subprocesses: (a) definition of geometric model, i.e. analysis model, (b) generation of nodes, and (c) generation of elements. One of commercial solid modelers is employed for three-dimensional solid structures. Node is generated if its distance from existing node points is similar to the node spacing function at the point. The node spacing function is well controlled by the fuzzy knowledge processing. The Delaunay method is introduced as a basic tool for element generation. Automatic generation of FE meshes for three-dimensional solid structures holds great benefits for analyses. Practical performances of the present system are demonstrated through several mesh generations for three-dimensional complex geometry.

• 대한본초학회지
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• 제27권1호
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• pp.17-25
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• 2012

Objectives : The objectives of this study lie in theoretical establishment of formulas for purging five viscera for curing the sthenic syndrome of five viscera through analyzing the component medicines and combination principles of Hyeongok's formulas for purging five viscera, and furthermore, maximizing the clinical use of them. Methods : This study analyzed the component medicines and combination principles of Hyeongok's formulas for purging five viscera based on the theory for properties and tastes of herbal medicines from the "Yellow Emperor's Canon of Internal Medicine", the theory for principal herbal medicine, assistant herbal medicine, adjuvant herbal medicine, dispatcher herbal medicine, and the five elements doctrine. Hyeongok's formulas for purging five viscera are Sagantang, Saseemtang, Sabeetang, Sapyeotang, and Pyeongshintang. Results : There are three methods for curing the sthenic syndrome of five viscera according to the five elements doctrine : in case of Sagantang purging the liver, purging the heart and invigorating the lung ; Saseemtang, purging the heart, purging the spleen and invigorating the kidney ; Sabeetang, purging the spleen, purging the lung and invigorating the liver ; Sapyeotang, purging the lung, purging the kidney and invigorating the heart ; Pyeongshintang, purging the kidney, purging the spleen and invigorating the spleen. Conclusions : First, to cure the sthenic syndrome of five viscera, the methods of purging five viscera, and invigorating five viscera should be used according to the five elements doctrine. Secondly, herbal medicines appropriate for those treatment methods should be chosen according to the theory for properties and tastes of herbal medicine and thirdly, the combination of those herbal medicines should be carried out according to the theory for principal herbal medicine, assistant herbal medicine, adjuvant herbal medicine, dispatcher herbal medicine. As a good example, Hyeongok's formulas for purging five viscera are combined according to the above theories. In conclusion, this formula was created by applying to the theory for properties and tastes of herbal medicines.

• Nuclear Engineering and Technology
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• 제48권1호
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• pp.43-54
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• 2016

In the present paper, development of the three-dimensional (3D) computational code based on Galerkin finite element method (GFEM) for solving the multigroup forward/adjoint diffusion equation in both rectangular and hexagonal geometries is reported. Linear approximation of shape functions in the GFEM with unstructured tetrahedron elements is used in the calculation. Both criticality and fixed source calculations may be performed using the developed GFEM-3D computational code. An acceptable level of accuracy at a low computational cost is the main advantage of applying the unstructured tetrahedron elements. The unstructured tetrahedron elements generated with Gambit software are used in the GFEM-3D computational code through a developed interface. The forward/adjoint multiplication factor, forward/adjoint flux distribution, and power distribution in the reactor core are calculated using the power iteration method. Criticality calculations are benchmarked against the valid solution of the neutron diffusion equation for International Atomic Energy Agency (IAEA)-3D and Water-Water Energetic Reactor (VVER)-1000 reactor cores. In addition, validation of the calculations against the $P_1$ approximation of the transport theory is investigated in relation to the liquid metal fast breeder reactor benchmark problem. The neutron fixed source calculations are benchmarked through a comparison with the results obtained from similar computational codes. Finally, an analysis of the sensitivity of calculations to the number of elements is performed.

• 대한한의학방제학회지
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• 제16권2호
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• pp.91-100
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• 2008

Background and Objectives : There are three kinds of formulas for purging the kidney to cure its sthenic syndrome based on the types of preparation formulas : Sashintang, Sashinhwan and Sashinsan. There are 4 kinds of Sashintang, 1 kind of Sashinhwan and 1 kind of Sashinsan. Combination of herbal medicines, carried out in formulas for purging the kidney, consists of various kinds depending on medical scientists' personal experience in medical treatment without any general principles, which makes it difficult to apply it to clinical use. The objectives of this study lie in theoretical establishment of Pyeongshintang for curing the sthenic syndrome of kidney through analyzing the component medicines and combination principles of Hyeongok's Pyeongshintang, and furthermore, maximizing the clinical use of Pyeongshintang. Methods : This study analyzed the component medicines and combination principles of Hyeongok's Pyeongshintang based on the theory for properties and tastes of herbal medicines from the "Yellow Emperor's Canon of Internal Medicine", the theory for principal herbal medicine, assistant herbal medicine, adjuvant herbal medicine, dispatcher herbal medicine, and the five elements doctrine. Hyeongok's Pyeongshintang is an odd prescription, composed of 7 kinds of ingredients : No.1 Rhizoma Alismatis (2don;7.5g), No.2 Poria (1don;3.75g), No.3 Radix Paeoniae Alba (1don), No.4 Fructus Chaenomelis (1don), No.5 Polyporus (1don), No.6 Cortex Cinnamomi (1don), and No.7 Radix Glycyrrhizae (1don) Results : There are three methods for curing the sthenic syndrome of kidney according to the five elements doctrine : purging the kidney, purging the liver and invigorating the spleen. First, if you suffer from the sthenic syndrome of the kidney, you need to purge your kidney. There are two available methods, including taste and property purgation according to the theory for properties and tastes of herbal medicines. They each imply the salty taste and the hot property purge the kidney. In the case of taste purgation, two herbal medicines with salty taste, Rhizoma Alismatis and Poria, are combined into the principal and assistant herbal medicine, respectively. For property purgation, two herbal medicines with the hot property, Polyporus and Cortex Cinnamomi, are combined into adjuvant herbal medicines. Secondly, if you suffer from the sthenic syndrome of the kidney, you need to purge your liver which is child in the mother-child relationship in inter-promotion among the five elements. There are two methods to purge the liver, including taste and property purgation according to the theory for properties and tastes of herbal medicines. They each mean the sour taste and the cool property purge the liver. Therefore, it is important to use sour herbal medicines for taste purgation and cool ones for property purgation. Both sour and cool herbal medicines, Radix Paeoniae Alba and Fructus Chaenomelis, are combined into adjuvant herbal medicines. Lastly, if you suffer from the sthenic syndrome of the kidney, you need to invigorate your spleen which is an element being surpassed in the relationship between the elements surpassed and ones not surpassed in inter-restraint among the five elements. There are two methods to invigorate the spleen, which include taste and property invigoration according to the theory for properties and tastes of herbal medicines. Taste invigoration means to invigorate the spleen with sweet taste and property invigoration to invigorate the spleen with warm property. Therefore, it is important to use sweet herbal medicines for taste invigoration and warm ones for property invigoration. Both sweet and warm herbal medicines, Polyporus and Cortex Cinnamomi, were combined to invigorate the spleen and purge the kidney. In addition, Radix Glycyrrhizae are combined as dispatcher herbal medicine, harmonizing all the herbal medicines composing the formula. Conclusions : First, to cure the sthenic syndrome of the kidney, the methods of purging the kidney and the liver, and invigorating the spleen should be used according to the five elements doctrine. Secondly, herbal medicines appropriate for those treatment methods should be chosen according to the theory for properties and tastes of herbal medicine and thirdly, the combination of those herbal medicines should be carried out according to the theory for principal herbal medicine, assistant herbal medicine, adjuvant herbal medicine, dispatcher herbal medicine. As a good example, Hyeongok's Pyeongshintang is combined according to the above theories. In conclusion, this formula was created by applying to the theory for properties and tastes of herbal medicines.

• Smart Structures and Systems
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• 제7권5호
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• pp.417-432
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• 2011

The present paper is devoted to vibration canceling and shape control of piezoelastic slender beams. Taking into account the presence of electric networks, an extended electromechanically coupled Bernoulli-Euler beam theory for passive piezoelectric composite structures is shortly introduced in the first part of our contribution. The second part of the paper deals with the concept of passive shape control of beams using shaped piezoelectric layers and tuned inductive networks. It is shown that an impedance matching and a shaping condition must be fulfilled in order to perfectly cancel vibrations due to an arbitrary harmonic load for a specific frequency. As a main result of the present paper, the correctness of the theory of passive shape control is demonstrated for a harmonically excited piezoelelastic cantilever by a finite element calculation based on one-dimensional Bernoulli-Euler beam elements, as well as by the commercial finite element code of ANSYS using three-dimensional solid elements. Finally, an outlook for the practical importance of the passive shape control concept is given: It is shown that harmonic vibrations of a beam with properly shaped layers according to the presented passive shape control theory, which are attached to an resistor-inductive circuit (RL-circuit), can be significantly reduced over a large frequency range compared to a beam with uniformly distributed piezoelectric layers.

• 한국강구조학회 논문집
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• 제18권3호
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• pp.349-359
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• 2006

본 연구에서는 직교좌표계에 근거한 적층복합 I형 박벽보의 유한요소 해석을 위한 새로운 블록 강도행렬을 제안한다. 변위장은1차 전단변형을 고려한 보 이론을 사용하여 정의되었다. 축방향 변위는 Timoshenko 보이론과 수정된 Vlasov 박벽보 이론을 결합하여 투영단면의 면 변형과 면외 변형의 합으로 나타낸다. 유도된 강성행렬은 휨 전단변형과 뒴 비틂에 의한 영향을 고려한다. 본 유한요소 에서는 2절점, 3절점, 4절점의 세 가지 보요소를 제안하였다. 3절점과 4절점 보 요소는 적층복합 보의 휨 해석에 효과적이었다. 다른 연구자의 수치해석 결과와 비교 검토를 통하여 새로운 유한요소의 활용성과 정확성을 입증하였다.

• 대한한의학방제학회지
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• 제15권1호
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• pp.137-144
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• 2007

Background and Objectives : There are three kinds of formulas for purging the spleen to cure its sthenic syndrome based on the types of preparation formulas : Sabeetang, Sabeehwan, Sabeesan and Sabeeeum. Another formulas called Sahwangtang, Sahwangsan. Sahwangeum is to purge the yellow colour of spleen. There are 8 kinds of Sabeetang, 3 kinds of Sabeehwan, 3 kinds of Sabeesan, 1 kind of Sabeeeum, 4 kinds of Sahwangtang, 7 kinds of Sahwangsan, and 1 kind of Sahwangeum. Combination of herbal medicines, carried out in formulas for purging the spleen, consists of various kinds depending on medical scientists' personal experience in medical treatment without any general principles, which makes it difficult to apply it to clinical use. The objectives of this study lie in theoretical establishment of Sabeetang for curing the sthenic syndrome of spleen through analyzing the component medicines and combination principles of Hyeongok's Sabeetang, and furthermore, maximizing the clinical use of Sabeetang. Methods : This study analyzed the component medicines and combination principles of Hyeongok's Sabeetang based on the theory for properties and tastes of herbal medicines from the ${\ulcorner}$Yellow Emperor's Canon of Internal Medicine${\lrcorner}$ , the theory for principal herbal medicine, assistant herbal medicine, adjuvant herbal medicine, dispatcher herbal medicine, and the five elements doctrine. Hyeongok's Sabeetang is an odd prescription, composed of 7 kinds of ingredients : No.1 Rhizoma Coptidis (2don;7.5g), No.2 Fructus Gardeniae (1don;3.75g), No.3 Ramulus Cinnamomi (1don), No.4 Gypsum Fibrosum (1don), No.5 Fructus Aurantii Immaturus (1don), No.6 Cortex Magnoliae Omcinalis (1don), and No.7 Radix Et Rhizoma Rhei (1don) Results : There are three methods for curing the sthenic syndrome of spleen according to the five elements doctrine : purging the spleen, purging the lung and invigorating the liver. First, if you suffer from the sthenic syndrome of the spleen, you need to purge your spleen. There are two available methods, including taste and property purgation according to the theory for properties and tastes of herbal medicines. They each imply the bitter taste and the cool property purge the spleen. In the case of taste purgation, two herbal medicines with bitter taste. Rhizoma Coptidis and Fructus Gardeniae, are combined into the principal and assistant herbal medicine, respectively. For property purgation, three herbal medicines with the cool property, Gypsum Fibrosum, Fructus Aurantii Immaturus and Radix Et Rhizoma Rhei, are combined into adjuvant herbal medicines. Secondly, if you suffer from the sthenic syndrome of the spleen, you need to purge your lung which is child in the mother-child relationship in inter-promotion among the five elements. There are two methods to purge the lung, including taste and property purgation according to the theory for properties and tastes of herbal medicines. They each mean the pungent taste and the warm property purge the lung. Therefore, it is important to use pungent herbal medicines for taste purgation and warm ones for property purgation. Both pungent and warm herb and property invigoration to invigorate the liver with warm property. Therefore, it is important to use pungent herbal medicines for taste invigoration and warm ones for property invigoration. Both pungent and warm herbal medicines, Ramulus Cinnamomi and Cortex Magnoliae Officinalis, were combined to invigorate the liver and purge the lung. In addition, Gypsum Fibrosum are combined as dispatcher herbal medicine, leading all the herbal medicines composing the formula to the spleen. Conclusions : First, to cure the sthenic syndrome of the spleen, the methods of purging the spleen and the lung, and invigorating the liver should be used according to the five elements doctrine. Secondly, herbal medicines appropriate for those treatment methods should be chosen according to the theory for properties and tastes of herbal medicine and thirdly, the combination of those herbal medicines should be carried out according to the theory for principal herbal medicine, assistant herbal medicine, adjuvant herbal medicine, dispatcher herbal medicine. As a good example, Hyeongok's Sabeetang is combined according to the above theories. In conclusion, this formula was created by applying to the theory for properties and tastes of herbal medicines.

• 한국문헌정보학회지
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• 제51권1호
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• pp.227-243
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• 2017

This study proposed a structural and semantic framework for the characterization of events and segments in Web videos that permits content-based searches and dynamic video summarization. Although MPEG-7 supports multimedia structural and semantic descriptions, it is not currently suitable for describing multimedia content on the Web. Thus, the proposed metadata framework that was designed considering Web environments provides a thorough yet simple way to describe Web video contents. Precisely, the metadata framework was constructed on the basis of Chatman's narrative theory, three multimedia metadata formats (PBCore, MPEG-7, and TV-Anytime), and social metadata. It consists of event information, eventGroup information, segment information, and video (program) information. This study also discusses how to automatically extract metadata elements including structural and semantic metadata elements from Web videos.