• Journal of Navigation and Port Research
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• v.37 no.1
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• pp.9-14
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• 2013

The e-navigation has been being developed in IMO is a sort of strategy to provide user-oriented services for safe navigation and environmental protection based on the architecture and its related services complying with the user needs. At NAV $57^{th}$ meeting in 2011, the overarching e-navigation architecture was approved which represent overall relationship only between onboard and ashore elements, so more detail technical architecture for each element should be developed for implementation in view of services and systems. Considering the continuous and iterative verification of e-navigation development process required by IMO, the relationship and traceability should be took in consideration between the outcome of e-navigation process and the element of the architecture. In this paper, we have surveyed literarily the user needs, result of gap analysis and practical solutions to address them and defined the architecture elements and their relationship considering the three kinds of views of DoDAF(Architecture Framework) of US department of Defence, in result, proposed the e-navigation shipboard technical architecture.

• Journal of Information Technology Services
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• v.12 no.4
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• pp.219-234
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• 2013

We introduced a framework of information systems audit methodology and applied to IS projects based on RFID/USN in six public organizations in South Korea. An analysis of five IS implementation projects shows the iterative technical specific risks are disclosed. The key 14 risk factors categorized into 4 classifications (Project Management, application, database, system architecture) which are based on the established IT audit framework in order to extend to the technology (RFID/USN) specific framework and apply to the other case as well. The implications of these findings for audit research and practice are discussed.

• IEIE Transactions on Smart Processing and Computing
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• v.6 no.3
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• pp.210-219
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• 2017

This paper proposes a modified min-max algorithm (MMMA) for nonbinary quasi-cyclic low-density parity-check (NB-QC-LDPC) codes and an efficient parallel block-layered decoder architecture corresponding to the algorithm on a graphics processing unit (GPU) platform. The algorithm removes multiplications over the Galois field (GF) in the merger step to reduce decoding latency without any performance loss. The decoding implementation on a GPU for NB-QC-LDPC codes achieves improvements in both flexibility and scalability. To perform the decoding on the GPU, data and memory structures suitable for parallel computing are designed. The implementation results for NB-QC-LDPC codes over GF(32) and GF(64) demonstrate that the parallel block-layered decoding on a GPU accelerates the decoding process to provide a faster decoding runtime, and obtains a higher coding gain under a low $10^{-10}$ bit error rate and low $10^{-7}$ frame error rate, compared to existing methods.

• Advances in Computational Design
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• v.2 no.1
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• pp.71-87
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• 2017

This study focuses on the efficiency and applicability of dynamic relaxation methods in form-finding of membrane structures. Membrane structures have large deformations that require complex nonlinear analysis. The first step of analysis of these structures is the form-finding process including a geometrically nonlinear analysis. Several numerical methods for form-finding have been introduced such as the dynamic relaxation, force density method, particle spring systems and the updated reference strategy. In the present study, dynamic relaxation method (DRM) is investigated. The dynamic relaxation method is an iterative process that is used for the static equilibrium analysis of geometrically nonlinear problems. Five different examples are used in this paper. To achieve the grading of the different dynamic relaxation methods in form-finding of membrane structures, a performance index is introduced. The results indicate that viscous damping methods show better performance than kinetic damping in finding the shapes of membrane structures.

• Structural Engineering and Mechanics
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• v.27 no.5
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• pp.541-554
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• 2007

A simplified yet effective design procedure for viscous dampers was presented based on improved capacity spectrum method in the context of performance-based seismic design. The amount of added viscous damping required to meet a given performance objective was evaluated from the difference between the total demand for effective damping and inherent damping plus equivalent damping resulting from hysteretic deformation of system. Application of the method is illustrated by means of two examples, using Chinese design response spectrum and mean response spectrum. Nonlinear dynamic analysis results indicate that the maximum displacements of structures installed with supplemental dampers designed in accordance with the proposed method agree well with the given target displacements. The advantage of the presented procedure over the conventional iterative design method is also highlighted.

• International Journal of Naval Architecture and Ocean Engineering
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• v.9 no.6
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• pp.677-692
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• 2017

A numerical approach based on a potential flow method is developed to simulate the unsteady interaction between propeller and rudder. In this approach, a panel method is used to solve the flow around the rudder and a vortex lattice method is used to solve the flow around the propeller, respectively. An iterative procedure is adopted to solve the interaction between propeller and rudder. The effects of one component on the other are evaluated by using induced velocities due to the other component at every time step. A fully unsteady wake alignment algorithm is implemented into the vortex lattice method to simulate the unsteady propeller flow. The Rosenhead-Moore core model is employed during the wake alignment procedure to avoid the singularities and instability. The Lamb-Oseen vortex model is adopted in the present method to decay the vortex strength around the rudder and to eliminate unrealistically high induced velocity. The present methods are applied to predict the performance of a cavitating horn-type rudder in the presence of a 6-bladed propeller. The predicted cavity patterns compare well with those observed from the experiments.

• The Journal of the Acoustical Society of Korea
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• v.15 no.4E
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• pp.21-27
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• 1996

In this paper, we propose a discriminative training algorithm for the stochastic segment model (SSM) in continuous speech recognition. As the SSM is usually trained by maximum likelihood estimation (MLE), a discriminative training algorithm is required to improve the recognition performance. Since the SSM does not assume the conditional independence of observation sequence as is done in hidden Markov models (HMMs), the search space for decoding an unknown input utterance is increased considerably. To reduce the computational complexity and starch space amount in an iterative training algorithm for discriminative SSMs, a hybrid architecture of SSMs and HMMs is programming using HMMs. Given the segment boundaries, the parameters of the SSM are discriminatively trained by the minimum error classification criterion based on a generalized probabilistic descent (GPD) method. With the discriminative training of the SSM, the word error rate is reduced by 17% compared with the MLE-trained SSM in speaker-independent continuous speech recognition.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.982-985
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• 1999

An efficient technique to trade off speed for resolution is the sigma-delta modulation (SDM). This paper proposes a new SDM architecture to improve conversion rates and SNR(Signal-to Noise Ratio) by using master clock and four divided clock. The charateristics of the proposed SDM are simulated in MATLAB environment. and optimizing the capacitor sizes is done by iterative processing. other analog characteristics are simulated using 0.65${\mu}{\textrm}{m}$ n-well CMOS process, double poly and single metal. The result of simulation shows that more increasing the effective bits of internal ADC/DAC, bigger the improvement of SNR.

• Journal of the Korean Institute of Intelligent Systems
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• v.10 no.4
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• pp.310-314
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• 2000

This paper proposes a new parallel architecture for extracting the object from binarized images using recurrent linear threshold neural networks. Binary functions are initially obtained from the existing iterative thinning algorithms, and the linear threshold neural threshold neural networks are then synthesized using the MSP term grouping algorithm. Experimental results show that the proposed architectures can be implemented easier than with other existing methods.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.416-416
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• 2000

The Systems Engineering, as a methodology for engineering and management of today's ever-growing complex system, is a comprehensive and iterative problem-solving process. The process centers on the analysis and management of the stakeholders'needs throughout the entire Life-cycle of a system and searches for an optimized system architecture. There are many essential needs and requirements to be met when a system development task is carried out. Systems Engineering Management PLan(SEMP), as a specification for system development process, must be established to satisfy constraints and requirements of stakeholders successfully and to prevent cost overrun and schedule delay. The paper suggests a systematic SEMP development process and demonstrates a data model and schema for computer-aided systems engineering software, RDD-100, for use in the development and management of SEMP These are being applied to the systems engineering technology development task for the next-generation high-speed railway systems in progress.