• 한국기계연구소 소보
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• s.17
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• pp.157-165
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• 1987

The SWATH concept hull form which is capable of high speed navigation with small oscillatory motions in waves, was developed from the catamaran type hull forms. This paper describes how the motion of a SWATH ship in irregular waves can be reduced by regulating the stabilizing fins. The optimal regulator and LQG (Linear Quadratic Gaussian) controller for vertical plane motion have been applied for both platforming mode and contouring mode controls. The calculations of hydrodynamic coefficients and external forces are possible for defining the system equation for the design purpose of motion control. Performances of the controlled system are compared with those of original system.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2006.11a
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• pp.396-400
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• 2006

Because of rapid growth of economy and development of the communication technology of modem society, office space's shape and business contents are highly diversified. And these changes made a new working style, homeworkers who work in their house. For increasing homeworker's working efficiency, it needs a space plan which can coexist home's original functions and business functions. The purpose of this study was designed a multiplex house used a co-operative house's concept which based on the data which collected by man to man case research about operators of online shopping malls.

• Journal of the Korean Society of Costume
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• v.63 no.8
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• pp.106-124
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• 2013

Compared to traditional fashion design, modern fashion design is used as a means that creates original and multiple types of beauty beyond fixed and standardized concept and form. Overlapping technique is the most suitable means to shed classical, authoritative and conservative form and it enables diverse borrowing and quotation for creation. This study aimed to analyze overlapping techniques that are expressed in art, architecture and fashion to find out its characteristics in the field of fashion. The result of this study is as follows. Based on theories of visual perception and advance research, types of overlapping technique were classified as pile, repetition, penetration and transparency. When comparing overlapping techniques in modern fashion with those of painting and architecture, fashion was distinctive in that it had movement and communicativeness through overlapping of fashion and the human body. Therefore, the overlapping technique has wide application and adaptation and can cause specialty, movability, communicativeness and collectivity, which can arouse psychological inspiration.

• ETRI Journal
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• v.25 no.6
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• pp.535-537
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• 2003

We propose a rigorous 2D approximation technique for the 3D waveguide structures; it can minimize the well-known approximation errors of the commonly used effective index method. The main concept of the proposed technique is to compensate for the effective cladding index in the equivalent slab model of the original channel waveguide from the modal effective index calculated by the nonuniform 2D finite difference method. With simulations, we used the proposed technique to calculate the coupling characteristics of a directional coupler by the 2D beam propagation method, and the results were almost exactly the same as the results calculated by the 3D beam propagation method.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.343-346
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• 2005

In this study, a basic concept of wavelet encoding and its advantages over Fourier based phase encoding application. Wavelet encoding has been proposed as an alternative way to Fourier based phase encoding in magnetic resonance imaging. In wavelet encoding, the RF pulse is designed to generate wavelet-shaped excitation profile of spins. From the resulting echo signals, the wavelet transform coefficients of spin distribution are acquired and an original spin density is reconstructed from wavelet expansion. Wavelet encoding has several advantages over phase encoding. By minimizing redundancy of the data acquisition in a dynamic series of images, we can avoid some encoding steps without serious loss of quality in reconstructed image. This strategy may be regarded as data compression during imaging. Although there are some limitations in wavelet encoding, it is a promising scheme in a dynamic imaging.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.3
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• pp.1210-1230
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• 2015

Android is the world's most utilized smartphone OS which consequently, also makes it an attractive target for attackers. The most representative method of hacking used against Android apps is known as repackaging. This attack method requires extensive knowledge about reverse engineering in order to modify and insert malicious codes into the original app. However, there exists an easier way which circumvents the limiting obstacle of the reverse engineering. We have discovered a method of exploiting the Android code-signing process in order to mount a malware as an example. We also propose a countermeasure to prevent this attack. In addition, as a proof-of-concept, we tested a malicious code based on our attack technique on a sample app and improved the java libraries related to code-signing/verification reflecting our countermeasure.

• World Technopolis Review
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• v.5 no.2
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• pp.98-107
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• 2016

By highlighting the efficiencies gained from regional specialization, the cluster concept has distracted economic development officials from their traditional role of diversifying regional and local economies. Clustering was a viable strategy for much of the 18 years following its original appearance in the literature. Now, two events cast doubt on the continued viability of cluster-based specialization. First, the digital convergence has blurred the boundaries that once separated one industry from another. An industry cluster strategy becomes difficult when the industry cannot be defined. Second, many cluster initiatives fail. Combining literature search with the system-theoretic notions of efficiency and redundancy, we find many factors moderate cluster success. This implies regions facing uncertain success in their cluster-building efforts should thoroughly understand their unique circumstances and build upon them. Regions with successful clusters are advised to aim for multiple related clusters or superclusters.

• Journal of the Korean Society for Precision Engineering
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• v.9 no.2
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• pp.81-91
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• 1992

A control methodology for suppressing the elastodynamic responses of high-speed flexible linkage mechanisms is presented by adopting the concept of smart structures featuring piezoelectric films. The dynamic modeling of the proposed mechanism is accomplished by employing a finite element formulation which accounts for dynamic motion in both inertial and elastic coordinates. The dynamics of piezoelectric actuators and sensors bonded on the original flexible structure are developed for one-dimensional beam in conjunction with the modal analysis. The linear optimal controller which consists of a feedback control law and a Luenberger observer is employed. Numerical simulation is performed to evaluate the improvement of elastodynamic responses.

• Journal of Fashion Business
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• v.11 no.4
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• pp.173-182
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• 2007

The concept of wearable computer says to be able to connect to network freely without restrict of place and time through the garment that contain the wire and circuit. Thereby we can realize the ubiquitous circumstances. Wearable computer plays a role of center in controlling the electronic equipments under the ubiquitous circumstances and also it will become the main stream of the future computer development. The current wearable computer displays ugly appearance by attaching the parts of computer on the garment instead of installing them in the box. However, as size of computer components are minimized and it's speed is getting faster, it is certain that wearable computer will evolve as fashionable computer, still retaining garment's original purpose such as fitting and fasion even though the computer is being installed to the clothing. This study reviewed about components, future market share, developed goods, human-being becoming cyborg, application area, restrict and on-going research of wearable computer.

• Journal of Mechanical Science and Technology
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• v.20 no.12
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• pp.2034-2042
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• 2006

In this study, a complete 3D surface reconstruction method is proposed based on the concept that the vertices, of surface model can be completely matched to the unstructured point cloud. In order to generate the initial mesh model from the point cloud, the mesh subdivision of bounding box and shrink-wrapping algorithm are introduced. The control mesh model for well representing the topology of point cloud is derived from the initial mesh model by using the mesh simplification technique based on the original QEM algorithm, and the parametric surface model for approximately representing the geometry of point cloud is derived by applying the local subdivision surface fitting scheme on the control mesh model. And, to reconstruct the complete matching surface model, the insertion of isolated points on the parametric surface model and the mesh optimization are carried out. Especially, the fast 3D surface reconstruction is realized by introducing the voxel-based nearest-point search algorithm, and the simulation results reveal the availability of the proposed surface reconstruction method.