• Journal of Positioning, Navigation, and Timing
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• v.13 no.3
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• pp.309-317
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• 2024

Satellite and receiver Inter-Frequency Biases (IFBs) should be estimated or calibrated by pre-defined values for generating precise navigation messages and augmentation data in satellite navigation systems or the augmentation system. In this paper, a Kalman filter is designed and implemented to estimate the ionospheric delay and satellite/receiver IFBs using a regional receiver network. First, an ionospheric model and its filter parameter is defined based on previous studies. Second, a measurement model for estimating the relative satellite/receiver IFBs without any constraints is proposed. Third, a procedure for ensuring the continuity of estimation is proposed in this paper. To verify the performance of the designed filter, six Continuously Operating Reference Stations (CORSs) are selected. Finally, the stability and accuracy of satellite/receiver IFB estimation are analyzed.

• Journal of the Society of Disaster Information
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• v.19 no.2
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• pp.363-371
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• 2023

Purpose: This paper aims to develop evaluation criteria of Plan- 'Understanding the Organization' in the PDCA(Plan-Do-Check-Act) requirements of ISO 22301 which is a global standard in the area of BCMS(Business Continuity Management System). Method: The group of 20 experts in the BCMS checked for the validity of the evaluation criteria of Plan- 'Understanding the Organization' by the modified Delphi technique and relative importance are surveyed by the group. Results: As a result, the 12 evaluation criteria with relative importance that can be applied for BCMS evaluation of the organizations are developed and proposed. Conclusion: In order to introduce a quantitive evaluation in the BCMS, it was concluded that evaluation criteria need to be chosen and given relative importance, thus the criteria with the importance could be used for effective evaluation

• Journal of the Korean earth science society
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• v.32 no.6
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• pp.629-639
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• 2011

Based on Maxwell-Eucken(ME) model, which is one of structural models, a new model for predicting the effective thermal conductivity of variably saturated porous materials is proposed. The new model is a linear combination of three ME models having matrix, water, and air as a continuous phase. The coefficient of the corresponding linear equation is defined by a parameter referred to as 'the continuity coefficient', which provides a relative degree of continuity of each phase. The continuity coefficient of matrix is assumed to be linearly proportional to porosity. The model can be linear or nonlinear depending on how the continuity coefficients of water and air vary with water saturation. The feasibility of the proposed model was examined by both numerical and experimental results. Both linear and nonlinear models showed a high accuracy of prediction with $R^2$ values of 0.86-0.98 and 0.88-0.99, respectively. The numerical and experimental results also showed that the continuity coefficient of matrix was linearly proportional to porosity. Therefore, the proposed prediction model can be effectively used to estimate effective thermal conductivity of unsaturated porous materials by measuring porosity, water content and mineralogical compositions of matrix.

• Honam Mathematical Journal
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• v.30 no.2
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• pp.207-217
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• 2008

Digital geometry has strongly contributed to the study of a discrete topological space $X{\subset}{\mathbf{Z}}^n$ with k-adjacency of ${\mathbf{Z}}^n$. As a survey-type article, we review various utilities of digital geometry.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2270-2273
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• 2003

Fuzzy logic control has been widely implemented in air conditioning and ventilation systems which has uncertainty or high robust system. Since the dynamic behaviors of the systems contain complexity and uncertainty in its parameters , several fuzzy logic controllers had been implemented to control room temperature in the field of air conditioning system. In this paper, the fuzzy logic control has been developed to control room temperature and humidity in the precision air conditioning systems. The nonlinear mathematical model was formulated using energy and continuity equations. MATLAB was used to simulate the fuzzy logic control of the multi-variable air conditioning systems. The simulation results show that fuzzy logic controller can reduce the steady-state errors of the room temperature and relative humidity in multivariable air conditioning systems. The offset are less than 0.5 degree Celsius and 3 percent in relative humidity respectively under random step disturbance in heating load and moisture load respectively

• Atmosphere
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• v.18 no.4
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• pp.417-427
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• 2008

In this paper, we analyzed the physical and thermodynamic characteristics of fog by using the integrated water vapor (IWV) from Global Positioning System (GPS) networks and the regular observation data of meteorological stations in GPS sites. The cases of a radiation and an advection fog were selected as samples, the conversions of water substance from the water vapor to cloud water in fog were detected by the Bulk Water-Continuity Model, and the pattern analysis is adapted on GPS IWV, temperature, wind and relative humidity. Under the specific hypothesis (saturation and stable), GPS IWV could detect quantitatively the phase changing between the water vapor and cloud water content with condensation/evaporation during the formation and dissipation of fog. After it reaches to the saturation, the relative humidity can be a limited indicator for fog. However, GPS IWV can detect the status change of fog even after the saturation. It has indicated that GPS IWV could be a new observing technique for the processes of the fog formation and the dissipation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.12C
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• pp.1149-1155
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• 2007

In this paper, we propose a new overlap and add speech synthesis method which demonstrates improved continuity performance. The proposed method uses a weighted phase error function and minimizes the wave discontinuity of the synthesis signal, rather than the phase discontinuity, to estimate the mid-point phase. Experimental results show that the proposed method improves the continuity between the synthesized signals relative to the existing method.

• Human Ecology Research
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• v.52 no.6
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• pp.639-649
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• 2014

The main purpose of this study was to find the relationship between the delinquency-onset time in the source and the continuity of delinquency. In order to achieve this objective, we divided 350 first-year high school students into three groups early-onset type, late-onset type, and non-delinquent adolescents on the basis of the delinquency onset. The results of this study were as follow: (1) for the boys, the early-onset type shows a higher continuity of delinquency than both the late-onset type and the general adolescents. On the other hand, for the girls, the early-onset type shows a higher continuity of delinquency than the late-onset type, but there was no difference in the persistence duration between the late-onset type and the non-delinquent adolescents. (2) For the boys, the examination reveals that the early-onset type has a higher degree of sensation seeking and impulsivity than the general adolescents. In addition, the early-onset type shows a higher degree of sensation seeking than the late-onset type, whereas the two show no difference in impulsivity. For the girls, sensation seeking did not show any difference depending on the delinquency onset. However, more impulsivity appeared in the early-onset type than in the late-onset type or the non-delinquent adolescents. (3) The relative priorities of variables determining the group to which the students belong on the basis of the delinquency onset are in the order of sensation seeking and juvenile impulsivity. Therefore, this study, suggests that the early-onset type requires a different kind of intervention than the late-onset type.

• The KIPS Transactions:PartB
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• v.10B no.1
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• pp.57-66
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• 2003

We propose a technique to extract a relevant passage from text collection based on field-associated terms since they tries to concentrate relevant text to users query. Documents are supposed to be managed as a whole without any segmentation into small pieces, but the method presented is independent upon any text-embedded auxiliary information, and is based on topic continuity and transition. For users needs-relative sentences or passages, we present a passage retrieval techniques by using occurrence frequency of a field-associated term to delimit text, that is likely to be relevant to a particular topic, considering continuity and transition within topic flowing in text. We evaluate 50 Japanese documents and verify the usefulness with 82% for average precision and 63% for recall.

• Journal of the Korea Concrete Institute
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• v.25 no.5
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• pp.517-528
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• 2013

The modular technology has been already applied in automotive industry, plant and shipbuilding industry. Recently, the modular technology was applied in bridge construction. The modular bridge is different from the existing precast bridges in terms of standardized design that the detailed design of members is omitted by using the standard modules; the design of the modular bridge is completed by only assembling the standard modules without design in member level. The girder-type precast modular bridge has been developed as a simply supported bridge. The girder-type precast modular bridge could be applied to the multi-span bridges through the continuity method. The continuity of the girder-type precast modular bridge is achieved by using the link slab which is easy to construction and appropriate to the rapid construction. The link slabs have been used as the type of reinforced concrete structure in US from the 1950's. In 2000's, the link slab using the engineered cementitious concrete (ECC link slab) has been developed. In this study, the RC type link slab which is more reproducible and economic relative to the ECC link slab was used for the continuity of the girder-type precast modular bridges, and the construction detail of RC type link slab was modified. In addition, the modified iterative design method of RC type link slab was proposed in this study. To verify the proposed design method, the flexural tests were conducted using the RC type link slab specimens. Also, the fatigue test using the mock-up specimen was conducted with cyclic loading condition up to two million cycles.