• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.452-455
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• 2004

MSC (Multi-Spectral Camera) system is a remote sensing instrument to obtain high resolution ground image. EOS (Electro-Optic System) for MSC mainly consists of PMA (Primary Mirror Assembly), SMA (Secondary Mirror Assembly), HSTS (High Stability Telescope Structure) and DFPA (Detector Focal Plane Assembly). High performance of EOS makes it possible for MSC system to provide high resolution and high quality ground images. Temperature of the EOS needs to be controlled to be in a specific range in order not to have any thermal distortion which can cause performance degradation. It is controlled by full redundant CPU based electronics. The validity of thermistor readings can be checked because a few thermistors are installed on each control point on EOS. Various kinds of thermal control logics are used to prevent 'Single Point Failure'. Control logic has a few set of database in order not to be corrupted by SEU (Single Event Upset). Even though the thermal control logic is working automatically, it can also be monitored and controlled by ground-station operator. In this paper, various ways of thermal control logic for EOS in MSC will be presented, which include thermal control mode and logic, redundancy design and status monitoring and reporting scheme.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.125-127
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• 2004

High-resolution satellite images offer abundance information of the earth surface for remote sensing applications. The information includes geometry, texture and attribute characteristic. The pixel-based image classification can't satisfy high-resolution satellite image's classification precision and produce large data redundancy. Object-oriented information extraction not only depends on spectrum character, but also use geometry and structure information. It can provide an accessible and truly revolutionary approach. Using Beijing Spot 5 high-resolution image and object-oriented classification with the eCognition software, we accomplish the cultures' precise classification. The test areas have five culture types including water, vegetation, road, building and bare lands. We use nearest neighbor classification and appraise the overall classification accuracy. The average of five species reaches 0.90. All of maximum is 1. The standard deviation is less than 0.11. The overall accuracy can reach $95.47\%.$ This method offers a new technology for high-resolution satellite images' available applications in remote sensing culture classification.

• Journal of the Society of Naval Architects of Korea
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• v.50 no.6
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• pp.383-389
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• 2013

Analysis and review of survivability is one of the most important aspects when naval vessels are designed. Because aiming points of threat towards the naval vessels in the battle field could not be estimated exactly, probabilistic and statistic approach is frequently introduced to evaluate and enhance the vessel survivability. Some commercial survivability analysis programs are used to perform the analysis for enhancement of susceptibility, vulnerability and recoverability but, they are usually classified and impossible to be exported to other countries because of their national security. In this paper, a simplified vulnerability analysis program is developed to evaluate the vulnerability of the warship in aspects of structure, redundancy and its mission capability at the conceptual design stage. To verify the developed program, the analysis results were compared with those of the commercial program MOTISS(Measure of Total Integrated System Survivability).

• International Journal of High-Rise Buildings
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• v.3 no.1
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• pp.35-48
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• 2014

In designing a 300 meter high skyscraper expected to be the tallest building in Japan, an earthquake-ridden country, we launched on the full-scale performance based design to ensure redundancy and establish new specifications using below new techniques. The following new techniques are applied because the existing techniques/materials are not enough to meet the established design criteria for the large-scale, irregularly-shaped building, and earth-conscious material saving and construction streamlining for reconstructing a station building are also required: ${\bullet}$ High strength materials: Concrete filled steel tube ("CFT") columns made of high-strength concrete and steels; ${\bullet}$ New joint system: Combination of outer diaphragm and aluminium spray jointing; ${\bullet}$ Various dampers including corrugated steel-plate walls, rotational friction dampers, oil dampers, and inverted-pendulum adaptive tuned mass damper (ATMD): Installed as appropriate; and ${\bullet}$ Foundation system: Piled raft foundation, soil cement earth-retaining wall construction, and beer bottle shaped high-strength CFT piles.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.12
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• pp.6017-6037
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• 2017

In a multi-resolution image encoding system, the image is encoded into a single file as a layer of bit streams, and then it is transmitted layer by layer progressively to reduce the transmission time across a low bandwidth connection. This encoding scheme is also suitable for multiple decoders, each with different capabilities ranging from a handheld device to a PC. In our previous work, we proposed an edge adaptive hierarchical interpolation algorithm for multi-resolution image coding system. In this paper, we enhanced its compression efficiency by adding three major components. First, its prediction accuracy is improved using context adaptive error modeling as a feedback. Second, the conditional probability of prediction errors is sharpened by removing the sign redundancy among local prediction errors by applying sign flipping. Third, the conditional probability is sharpened further by reducing the number of distinct error symbols using error remapping function. Experimental results on benchmark data sets reveal that the enhanced algorithm achieves a better compression bit rate than our previous algorithm and other algorithms. It is shown that compression bit rate is much better for images that are rich in directional edges and textures. The enhanced algorithm also shows better rate-distortion performance and visual quality at the intermediate stages of progressive image transmission.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.2
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• pp.231-237
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• 2008

With the advent of sound field simulator, many sound fields have been reproduced by obtaining the impulse responses of specific acoustic spaces like famous concert hall, opera house. This sound field reproduction has been done by the linear convolution operation between the sound input signal and the impulse response of certain acoustic space. However, the conventional finite impulse response based linear convolution operation always makes real-time implementation of sound field generator impossible due to the large amount of computational burden. This paper introduces the fast convolution method using perceptual redundancy in the processed signals, input audio signal and room impulse response. Temporal and spectral real-time masking blocks are implemented in the proposed convolution structure. It reduces the computational burden of convolution methods for real-time implementation of a sound field generator. The conventional convolutions are compared with the proposed one in views of computational burden and sound quality. In the proposed method, a considerable reduction in the computational burden was realized with acceptable changes in sound quality.

• The Pure and Applied Mathematics
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• v.27 no.3
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• pp.137-155
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• 2020

Redundancy is commonly employed to improve system reliability. In most situations, components in the standby configurations are assumed statistically similar but independent. In many realistic models, all parts in standby are not treated as identical as they have different failure possibilities. The operational structure of the system has subsystem-1 with five identical components working under 2-out-of-5: G; policy, and the subsystem-2 has two units and functioning under 1-out-of-2: G; policy. Failure rates of units of subsystems are constant and assumed to follow an exponential distribution. Computed results give a new aspect to the scientific community to adopt multi-dimension repair in the form of the copula.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.4 s.97
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• pp.205-212
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• 1999

A three dimensional binary parallel robot manipulator uses actuators which have only two stable states and its structure is variable geometry truss. As a result, it has a finite number of states and fault tolerant mechanism because of kinematic redundancy. This kind of robot manipulator has some advantages compared to a traditional one. Feedback control is not required, task repeatability can be very high, and finite state actuators are generally inexpensive. Because the number of states of a binary robot manipulator grows exponentially with the number of actuators it is very difficult to solve and inverse kinematic problem. The goal of this paper is to develop an efficient algorithm to solve an inverse kinematic problem of three dimensional binary parallel robot manipulator using a backbone curve when the number of actuators are too much. We first derive the coordinate transformations associated with a three degree of freedom in-parallel actuated robot manipulator. The backbone curve is generated optimally by considering the maximum roll and pitch angles of the robot manipulator configuration and length of link. Then, the robot manipulator is fitted along the backbone curve with some criterion.

• Journal of Environmental Impact Assessment
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• v.22 no.3
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• pp.265-276
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• 2013

This study assessed documentation status of each environmental assessment items by analyzing the 243 case of marine EIS on the Consultation System of Sea Area Utilization. Observed rate of tidal elevation, current, temperature, salinity in maine environment were below 20%. The EFDC tool is applied substantially in hydrodynamic modeling. The verification process, however, is very insufficient using the recent observed data. Also, in-situ assessment rate of pelagic organism such as phytoplankton was below 50%, and assessment for Chlorophyll a was not accomplished. Ecological index evaluation for zooplankton and benthic ecosystem were not considered in statements. Especially, the rational assessment on the fisheries resources and protected species were very limited. It was necessary that the core assessment items (checklists) were established for environmental scoping. Furthermore, suggestion of information related to development, regional coastal management plan, aquaculture farms, and facilities were enhanced. The redundancy problem of proceedings between Environmental Impact Assessment and Sea Area Utilization Assessment System was improved.

• Journal of Internet Computing and Services
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• v.8 no.2
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• pp.95-103
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• 2007

Many techniques have been proposed for mapping from XML to relations, but most techniques did not negotiate the semantics of XML data. The semantics is important to validate storage, query optimization, modification anomaly in process of schema design. Specially, functional dependencies are an important part of database theory, also it is basis of normalization for relational table in BCNF. This paper propose a new technique that reflect functional dependencies to store relation mapped from XML based on XML Schema. The technique can reduce storage redundancy and can keep up content and structure with constraint described by functional dependencies.