• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.3
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• pp.537-547
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• 2001

The paper proposes the fuzzy logic global approximate optimization strategies in optimal sizing of automotive A-pillar trim with rib structures for occupant head protection. Two different strategies referred to as evolutionary fuzzy modeling (EFM) and neuro-fuzzy modeling (NFM) are implemented in the context of global approximate optimization. EFM and NFM are based on soft computing paradigms utilizing fuzzy systems, neural networks and evolutionary computing techniques. Such approximation methods may have their promising characteristics in a case where the inherent nonlinearity in analysis model should be accommodated over the entire design space and the training data is not sufficiently provided. The objective of structural design is to determine the dimensions of rib in A-pillar, minimizing the equivalent head injury criterion HIC(d). The paper describes the head-form modeling and head impact simulation using LS-DYNA3D, and the approximation procedures including fuzzy rule generation, membership function selection and inference process for EFM and NFM, and subsequently presents their generalization capabilities in terms of number of fuzzy rules and training data.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.5
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• pp.421-426
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• 2017

In this study, we propose a method for predicting the mechanical properties of the printed circuit board (PCB) that has transversely isotropic characteristics. Unlike the isotropic material, there is no specific test standard for acquisition of the transversely isotropic properties. In addition, common material test methods are not readily applicable to that type of laminated thin plate. Utilizing the natural frequency obtained by a modal test and the sizing optimization technique provided in $OptiStruct^{(R)}$, the mechanical properties of a PCB were derived to minimize the difference between test and analysis results. In addition, the validity of the predicted mechanical properties was confirmed by the MAC (Modal Assurance Criteria) value of each of the compared mode shapes. This proposed approach is expected to be extended to the structural analysis for the design verification of the top product that includes a PCB.

• Journal of the Society of Naval Architects of Korea
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• v.38 no.1
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• pp.116-122
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• 2001

In this paper, to make a base of the fire safety assessment about ship's fire protection design and Classification Society rule, statistical informations and modeling techniques for the fire safety engineering are investigated and probabilistic safety assessment methods in the structural reliability engineering are introduced. FSEM(Fire Safety Evaluation Module) developed in this paper calculates the probability of fatality, which can be used as an index of fire safety. FSEM is used to calculate the probability of fatality of the evacuees in a small room installed according to the rules for fire-proof. Sensitivity analysis is executed to investigate FSEM's applicability to ship. From results, the necessity of new criterion for ship's fire safety design, the need to study the human behavior in the evacuation from fire, and the development of new fire progress model considering special situations in ships are acknowledged.

• Journal of Educational Research in Mathematics
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• v.22 no.4
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• pp.477-494
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• 2012

This study is to review the content organization and developmental ways of the unit on the mixed calculations and explore the alternatives on the basis of students' responsive examples and error patterns with relation to the mixed calculations, mnemonics of PEMDAS and historical context with relation to the order of operations. Then I analyzed the textbook and manual for teachers of the unit of mixed calculations of fourth grade and improvement about teaching the mixed calculations. First, I pointed out illogical connection between practical problem and rules of order of operations. Second, I suggested constructing a textbook by considering conventional character of order of operations. Third, I pointed out the importance of structural understanding of an expression of mixed calculations and various strategies with relation to teaching and learning. This study is suggestive for textbook development of the mixed calculations.

• Journal of Navigation and Port Research
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• v.37 no.5
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• pp.559-565
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• 2013

The purpose of this study is to prioritize improvement factors of the tug services in terms of the structural problem, operating system and the present condition of the tug at each port in Korea. It was identified that the tug operating system needs to be mostly improved among the improvement factors of the tug services in Korea. In addition, free contract and rotating system were found to be important factors which need to be improved comparing to other factors such as service quality, tug rules, operating practices of council for tug operation and customer factor. The service attitude of the tug companies was regarded as an important element. And the tug entry system appeared to be an important item. Finally, laws relating to tug business needs to be revised which allow new tug companies enter into the market. As the result of AHP analysis for tug systems and service improvement factors, some fundamental changes of tug operation systems are urgently needed.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.413-418
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• 2001

Fundamental failure mode in a laminated composite pinned-joint is proposed to assess damage resulting from stress concentration in the plate. The joint area is a region with stress concentrations thus a complicated stress state exists. The modeling of damage in a laminated composite pinned-joint presents many difficulties because of the complexity of the failure process. In order to model progressive from initial to final, finite element methods are used rather than closed form stress analyses. Failure analysis must be a logical combination of suitable failure criteria and appropriate material properties degradation rules. In this study, the material properties which were obtained in previous study, the preparing process of the bearing strength test for a pinned joint CFRP composite plate subjected to in-plane loading at low temperature, and the FEM result of progressive damage model using ANSYS program are summarized to assess the structural safety of CFRP plate used in the magnetic supporting post of KSTAR(Korea Superconducting Tokamak Advanced Research).

• Journal of KIISE:Computer Systems and Theory
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• v.32 no.11_12
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• pp.617-628
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• 2005

The services for ubiquitous computing environments have to provide automatically user-specific adaptive services in dynamically changed environments with many informations provided by both a user and his/her environment. Workflows used in business and distributed computing environments support service automation by connecting many tasks with rules or orderings of tasks. Therefore we must specify context information on transition condition to support context-aware services by adapting a workflow to ubiquitous computing environments. In this paper, we present a structural context model to specify context information on transition constraints of the workflow. And we propose an uWDL Ubiquitous Workflow Description Language) based on web services, which provides web service interfaces which are standardized and independent on heterogeneous and various platforms, protocols, and languages. The uWDL tan be interpreted and executed by a workflow engine, and provide users autonomic services based on context-awareness.

• The Transactions of the Korea Information Processing Society
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• v.5 no.5
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• pp.1246-1256
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• 1998

MIB(Management Information Base), one of the key components of network management system, is a conceptual repository for the information of the various managed objects. MIB stores and manages all the structural and operational data of each managed resources. Therefore, MIB should be protected properly from inadvertant user access or malicious attacks. International standard ISO/IEC 10164-9 describes several managed object classes for the enforcement of MIB security. Those managed object classes described access control rules for security policy. But the exact authorization procedures using those newly added managed object classes are not presented. In this paper, we divide managed object classes into two groups, explicit and implicit ones, and describe the access authorization procedure in Z specification language. Using Z as a description method for both authorization procedure and GDMO's action part, the behaviour of each managed object class and access authorization procedure is more precisely and formally defined than those of natural language form.

• Ocean and Polar Research
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• v.28 no.3
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• pp.273-285
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• 2006

As the political arguments on international power concept has gradually been deepened, the role of international regimes, defined as principles, norms, rules, and decision-making procedures around which nation-actors' expectations converge in a given issue-area, has also been reinforced. There are many ways of understanding about international regimes. In terms of realistic theories, international regimes are one of methods of maintaining hegemonic power order of hegemonic nation and in terms of liberalistic theories, international regimes are understood as the products of mutual inter-dependence of nations in changing international society. As a matter of fact, if we take structural causes and regime consequences into severe consideration, we can find not a few characteristics of international regimes, such as security regime, world trade and fiance regime, ocean regime, environmental regime, human right regime, etc. This paper will examine the changing concept of power after World War II in three categories of hard power (military power), meta power (regime creating power), and soft power (advanced in cultural, diplomatical, and technological power). This paper will provide the evidence of why the changing power concepts will be strongly related with the emergence of international regimes. The UN convention on the law of the sea will chosen as a standard case of the ocean regime and it's regime structure and role will also be analysed in both realistic :md liberalistic theories. Futhermore, the nations' interests involved in the UN convention on the law of the sea will be analytically classified and finally a future prospectus of the UN convention on the law of the sea as an ocean regime will be tested.

• Korean Journal of Digital Imaging in Medicine
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• v.11 no.2
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• pp.85-92
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• 2009

This study, "The study about performance evaluations of mobile cover for X-ray's diffusion and distribution in mobile radiation" is based on the rules of mobile defense apparatus for radiation producer in 2006. To use the mobile cover for X-ray for diagnosis has been compulsory in common wards except operation rooms, emergency rooms and intensive care units. we have confirmed the effect in arbitrary shielding material after Qualitiy Control was carried out for accuracy in an experiment of mobile photographing equipment. The performance evaluation was conducted with the fabrics of selenium, 0.2 mmPb, 0.1 mmPb and aluminiums. Considering the result, we choosed 0.1 mmPb and attached cover to mobile photographing equipment. We have finished making the cover after drew up the draft to attach cover to mobile photographing equipment through the modeling and the structural analysis. the process of the study is that we assembled the manufactured structures and carried out the practical experiment to take the photograph after attaching the fabric of 0.1 mmPb to mobile photographing equipment. It is need of additional thesises hereafter that we compare the result between the part to improve for safety besides convenience in photographic experiment about clinical radiation and the effect of covering the diffusion in condition attached the cover.