• Proceedings of the Korea Information Processing Society Conference
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• 2009.04a
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• pp.1260-1263
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• 2009

제한된 배터리를 가지는 센서 네트워크의 수명을 길게 하기 위하여 에너지 소비를 줄이고 효율성을 높이는 다양한 방법이 제안되었다. 센서 노드에서의 데이터 전송은 가장 큰 에너지 소비 활동이 되기 때문에, 데이터가 전송되는 양을 줄여서 에너지 소비를 줄일 수 있는 방법이 한 부분으로 연구되고 있다. 본 논문에서는 이와 같은 특징을 반영하고, 시간적 연관성만을 고려한 데이터 퓨전 기법인 TiNA(Temporal coherency-aware in-Network Aggregation)를 기반으로 시간, 공간적 연관성을 동시에 고려하여 데이터 퓨전을 하는 효율적인 데이터 퓨전(Data Fusion) 기법을 제안하였다.

• Journal of Teachers' Pension
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• v.1
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• pp.189-241
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• 2016

1991년 사학연금제도에 재정계산제도가 도입되었으나 법적 근거만이 존재할 뿐 이를 위한 구체적인 시행주체 및 절차, 재정계산의 역할과 범위 등 주요 내용에 대한 명확한 규정이 결여되어 있다. 이에 따라 시기별로 재정계산 추진방법이 다소 상이한 측면이 있었으며, 결과적으로 사학연금 재정계산 실시의 일관성(coherency)과 신뢰성(credibility) 확보에 어려움이 노정되었다. 이러한 상황에서, 본 연구에서는 사학연금 재정계산 시행현황과 그 문제점을 살펴보고 국내·외 공적연금의 재정계산제도 시행사례를 비교·분석함과 동시에 정책적 시사점을 모색하였다. 이에 기초하여 우리나라 사학연금 재정계산제도의 향후 정책과제 및 개선 기본방향을 ①재정평가 및 재정계획 체계, ②재정계산 실시내용, ③재정계산보고서, ④담당주체 및 보고절차, ⑤재정계산 법적 근거 등을 위주로 하여 정책제언(政策提言)하였다. 이 글이 사학연금의 발전적인 재정계산 정책수립에 이바지하고 나아가서는 우리나라 공적연금의 지속가능한 재정정책 수립에도 중요한 밑거름이 되기를 기대한다.

• Applied Microscopy
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• v.50
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• pp.8.1-8.7
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• 2020

Two thickness measurement methods using an electron energy loss spectroscopy (EELS) and 10a convergent beam electron diffraction (CBED) were compared in an Fe-18Mn-0.7C alloy. The thin foil specimen was firstly tilted to satisfy 10a two-beam condition. Low loss spectra of EELS and CBED patterns were acquired in scanning transmission electron microscopy (STEM) and TEM-CBED modes under the two-beam condition. The log-ratio method was used for measuring the thin foil thickness. Kossel-Möllenstedt (K-M) fringe of the $13{\ba{1}}$ diffracted disk of austenite was analyzed to evaluate the thickness. The results prove the good coherency between both methods in the thickness range of 72 ~ 113 nm with a difference of less than 5%.

• Geophysics and Geophysical Exploration
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• v.12 no.1
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• pp.132-142
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• 2009

The Tamar rift valley runs through the City of Launceston, Tasmania. Damage has occurred to city buildings due to earthquake activity in Bass Strait. The presence of the ancient valley, the Tamar valley, in-filled with soft sediments that vary rapidly in thickness from 0 to 250mover a few hundreds metres, is thought to induce a 2D resonance pattern, amplifying the surface motions over the valley and in Launceston. Spatially averaged coherency (SPAC), frequency-wavenumber (FK) and horizontal to vertical spectrum ratio (HVSR) microtremor survey methods are combined to identify and characterise site effects over the Tamar valley. Passive seismic array measurements acquired at seven selected sites were analysed with SPAC to estimate shear wave velocity (slowness) depth profiles. SPAC was then combined with HVSR to improve the resolution of these profiles in the sediments to an approximate depth of 125 m. Results show that sediments thicknesses vary significantly throughout Launceston. The top layer is composed of as much as 20m of very soft Quaternary alluvial sediments with a velocity from 50 m/s to 125 m/s. Shear-wave velocities in the deeper Tertiary sediment fill of the Tamar valley, with thicknesses from 0 to 250m vary from 400 m/s to 750 m/s. Results obtained using SPAC are presented at two selected sites (GUN and KPK) that agree well with dispersion curves interpreted with FK analysis. FK interpretation is, however, limited to a narrower range of frequencies than SPAC and seems to overestimate the shear wave velocity at lower frequencies. Observed HVSR are also compared with the results obtained by SPAC, assuming a layered earth model, and provide additional constraints on the shear wave slowness profiles at these sites. The combined SPAC and HVSR analysis confirms the hypothesis of a layered geology at the GUN site and indicates the presence of a 2D resonance pattern across the Tamar valley at the KPK site.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.7
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• pp.619-628
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• 2000

Abstract Perspective views provide a powerful depth cue and thus aid the interpretation of complicated images. The main drawback of current perspective volume rendering is the long execution time. In this paper, we present an efficient perspective volume rendering algorithm based on coherency between rays. Two sets of templates are built for the rays cast from horizontal and vertical scanlines in the intermediate image which is parallel to one of volume faces. Each sample along a ray is calculated by interpolating neighboring voxels with the pre-computed weights in the templates. We also solve the problem of uneven sampling rate due to perspective ray divergence by building more templates for the regions far away from a viewpoint. Since our algorithm operates in object-order, it can avoid redundant access to each voxel and exploit spatial data coherency by using run-length encoded volume. Experimental results show that the use of templates and the object-order processing with run-length encoded volume provide speedups, compared to the other approaches. Additionally, the image quality of our algorithm improves by solving uneven sampling rate due to perspective ray di vergence.

• Journal of KIISE
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• v.43 no.3
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• pp.304-313
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• 2016

We present a novel memory-efficient parallel ray casting algorithm for unstructured grid volume rendering on multi-core CPUs. Our method is based on the Bunyk ray casting algorithm. To solve the high memory overhead problem of the Bunyk algorithm, we allocate a fixed size local buffer for each thread and the local buffers contain information of recently visited faces. The stored information is used by other rays or replaced by other face's information. To improve the utilization of local buffers, we propose an image-plane based ray grouping algorithm that makes ray groups have high coherency. The ray groups are then distributed to computing threads and each thread processes the given groups independently. We also propose a novel hash function that uses the index of faces as keys for calculating the buffer index each face will use to store the information. To see the benefits of our method, we applied it to three unstructured grid datasets with different sizes and measured the performance. We found that our method requires just 6% of the memory space compared with the Bunyk algorithm for storing face information. Also it shows compatible performance with the Bunyk algorithm even though it uses less memory. In addition, our method achieves up to 22% higher performance for a large-scale unstructured grid dataset with less memory than Bunyk algorithm. These results show the robustness and efficiency of our method and it demonstrates that our method is suitable to volume rendering for a large-scale unstructured grid dataset.

• Archives of design research
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• v.16 no.2
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• pp.375-384
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• 2003

This study is on the strategy for establishing successful corporate brand image, by understanding the need for increasing brand value based on the level of brand recognition. In order to carry this out, the PICS (Product Image Concentration System) is suggested, which includes Brand Image Analysis on a high-level, Product Image Programming based on the result of the image analysis, and Product Image Coherency Assessment and Management, resulting in setting up a guideline for gaining competitive advantage and brand management. Brand Image Analysis is a method that utilizes image association to understand brand disposition by analyzing the association pattern among available visual materials to measure the corporate and brand image inclinations. As the next step, Product Image Programming establishes design philosophy and principles based on the analysis of brand image, and the Visual Programming is a process for visualizing the intended product image direction. Lastly, Product Image Coherency Assessment examines whether to incorporate design philosophy and principles or not to arrive at an agreed evaluation criteria for developing designs coherent with the brand image. The PICS (Product Image Concentration System) is a practical method for increasing a company' competitive advantage and managing brand. The expectation on this system is to provide a guideline for applying brand image in design process more objectively. For further study, diversification of image spectrum based on expressive keywords and comparative analysis on images as well as a product image interpretation program to understand the order of visual materials will be necessary.

• The Journal of the Korea Contents Association
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• v.8 no.6
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• pp.1-7
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• 2008

The paper is to solve the problem of existing sound system, which has difficulties of system organization and the increase of additional install cost and unfriendly interior. To solve the existing system, we drew the new sound system based on PLC and studied it. A transmitter and a receiver were designed using the PLC chip INT5500CS. Sound system was configured with a CD player that sound signals are sent from the transmitter and a speaker connected to the receiver. For analysis of characteristics of this system, a USBPre external sound card and Smaart Live 5 which is a PC-based sound measuring program were added. As a result of our experiment, the measured signal level is $2{\sim}3$[dB] lower than reference signal, latency is 16.69[ms] and the specific character of coherency is bad in high frequency band. Otherwise, this system transmits and receives signals over 90[%] in good condition as a result of measuring pink noise, frequency(1kHz), and phase, magnitude. In view of the result so far achieved, the system designed our team has excellent performance, it resolves defect of existing audio signal transmition system.

• Journal of Distribution Science
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• v.17 no.2
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• pp.77-89
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• 2019

Purpose - This study presents the relationships between parent brand-self image congruence, parent brand -functional congruity, perceived fit between parent brand and extension product, and consumer's attitude toward extension product using the structural equation model. As for preceding concepts having a direct effect on consumer's attitude toward brand extension, the study focuses on parent brand-self image congruence and parent brand-functional congruity. It also looks at the effect of parent brand-self image congruence and parent brand-functional congruity on the consumer's attitude toward extension product and identifies if the perceived fit between parent brand and extension product is a concept playing a mediating role between parent brand-self image congruence or parent brand-functional congruity and consumer's attitude toward brand extension product. Research design, data, and Methodology - SPSS for Windows 18.0 and AMOS 18.0 were used for data analysis. Then, the Cronbach's α coefficient was obtained using SPSS for Windows 18.0 to measure reliability. In addition, the convergence and discriminative measures of the measured items were statistically verified using AMOS 18.0. Finally, we have validated a path model and a parameter model in which brand personality-self-matched attitude toward brand extension. Results - Studies have shown that the impact of parent brand-self image consistency and parent brand-functional consistency on the attitude of extended products was positive. Perceived fit between parent brand and extension products has been shown to play a role of intermediary between parent brand-self image congruence and consumer attitudes to extended products. However, perceived fit between parent brand and extension products did not play a role as intermediary between the parent brand-functional congruity and the attitude toward the extended product. Finally, in relation to the causal relationship between parent brand-congruity (self image/functionality) and attitudes to extended products. The effect of parent brand-functional coherency on attitudes toward extended products was found to be greater in groups with higher involvement than in those with lower involvement. Conclusions - Although few studies have been done on what variables mediated when parent brand-self image consistency and parent brand-functional coherency affect consumer attitude, this paper is significant in finding whether perceived fitness between the parent brand-congruity and the extension product is mediated.

• Applied Microscopy
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• v.25 no.2
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• pp.65-72
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• 1995

The interfacial structures of ZnSe/GaAs which were grown by single chamber MBE at $300^{\circ}C$ were investigated by high resolution transmission electron microscope working at 300 kV with resolution of 0.18 nm. The interfaces of ZnSe/GaAs whose thickness is 2,700 nm are wavy and extensive stacking faults were formed in ZnSe epilayer but the interfaces maintained the coherency with the substrate GaAs. The stacking faults are formed in {111} planes and their sizes are $10{\sim}20nm$ in length and two or three atomic layer in width with the density of $10^9/cm^2$. Micortwins and moire fringes are also observed. However. in 10 nm ZnSe epilayer, the interfaces are pseudomorphic and only moire fringes are observed in local areas. The cylindrical defects which are perpendicular to the interface with $50{\sim}60nm$ in length, were observed with the interval of 50 nm at ZnSe/GaAs interfaces in 2,700nm epilayer. The origin and character of these defects are unknown, however, they played a role of producing the structural defects at the interfaces.