• Journal of Drive and Control
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• v.13 no.4
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• pp.14-22
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• 2016

This paper presents a stochastic and predictive working-risk-assessment algorithm for excavators based on a one-layer laser scanner. The one-layer laser scanner is employed to detect objects and to estimate an object's dynamic behaviors such as the position, velocity, heading angle, and heading rate. To estimate the state variables, extended and linear Kalman filters are applied in consideration of laser-scanner information as the measurements. The excavator's working area is derived based on a kinematic analysis of the excavator's working parts. With the estimated dynamic behaviors and the kinematic analysis of the excavator's working parts, an object's behavior and the excavator's working area such as the maximum, actual, and predicted areas are computed for a working risk assessment. The four working-risk levels are defined using the predicted behavior and the working area, and the intersection-area-based quantitative-risk level has been computed. An actual test-data-based performance evaluation of the designed stochastic and predictive risk-assessment algorithm is conducted using a typical working scenario. The results show that the algorithm can evaluate the working-risk levels of the excavator during its operation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.574-577
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• 2007

While disk can be overwritten on updating data, because flash memory can not be overwritten on updating data, new data are updated in new area. If data are frequently updated, garbage collection, which is achieved by erasing blocks, should be performed to reclaim new area. Hence, because the number of erase operations is limited due to characteristics of flash memory, every block should be evenly written and erased. However, if data with access locality are processed by cost benefit algorithm with separation of hot block and cold block, though the performance of processing is high, wear-leveling is not even. In this paper, we propose CB-MB (Cost Benefit between Multi Bank) algorithm in which hot data are allocated in one bank and cold data in another bank, and in which role of hot bank and cold bank is exchanged every period. CB-MB showed that its performance was similar to that of others for uniform workload, however, the method provides much better performance than that of others for workload of access locality.

• Archives of design research
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• v.12 no.2
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• pp.19-28
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• 1999

Current technology does not emphasize closer connection through group collaboration, but rather underlines the distances and separations that are visible in today's society. As the interpretation of our territory of life which is still based on the model of the 'physical' of industrial era is no more valid, a different 'sense of belonging' corresponds to this new notion of territory. The main idea is how to make the sense of community to connect actual space with one child from each place. Therefore, the subject of this thesis is to design the system making children from distance to be closer, developing 'learning community' connecting with two classes across the globe. The contents include its studying in respect to the development of a non-geographical 'learning community' based on co-evolution, and to the system design of conceptual models for the community. In conclusion, the physical interface design is suggested to let user develop accurate mental models of the system.

• The Journal of the Korea Contents Association
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• v.19 no.8
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• pp.293-302
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• 2019

The purpose of this study was to examine the reliability and validity of Stroke Impact Scale 3.0 (SIS 3.0). Here, the SIS 3.0 was completed by 154 stroke patients (mean = 62.7; standard deviation [SD] = 9.43). Construct validity was verified by analyzing the correlation between SIS 3.0 sub-domains, and convergent validity was investigated by analyzing the correlation between the Modified Barthel Index (MBI) and the Mini-Mental State Examination-Korean (K-MMSE) version. The characteristics of each item were analyzed by internal consistency and item discrimination based on the classical item theory. Construct and convergent validity were verified through this study. Although the item i included in the emotion domain showed low item discrimination, all but this item showed high discrimination. Internal consistency was also high in all sub-domains.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.8
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• pp.1809-1818
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• 2010

In order to detect the skin color area from input images, many prior researches have divided an image into the pixels having a skin color and the other pixels. In a still image or videos, it is very difficult to exactly extract the skin pixels because lighting condition and makeup generate a various variations of skin color. In this thesis, we propose a method that improves its performance using hierarchical merging of 3D skin color model and context informations for the images having various difficulties. We first make 3D color histogram distributions using skin color pixels from many YCbCr color images and then divide the color space into 3 layers including skin color region(Skin), non-skin color region(Non-skin), skin color candidate region (Skinness). When we segment the skin color region from an image, skin color pixel and non-skin color pixels are determined to skin region and non-skin region respectively. If a pixel is belong to Skinness color region, the pixels are divided into skin region or non-skin region according to the context information of its neighbors. Our proposed method can help to efficiently segment the skin color regions from images having many distorted skin colors and similar skin colors.

• Therapeutic Science for Rehabilitation
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• v.2 no.1
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• pp.66-76
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• 2013

Objective : Based on the Model of Human Occupation (MOHO), this study was to identifies the goals setting of elderly person with dementia. Methods : For 5 weeks from May to June of 2012, MOHO-based interviews and Occupational Questionnaire(OQ), Interest checklist(IC), Volitional Questionnaire(VQ), The Assessment of Communication and Interaction Skills(ACIS), Occupational Performance History Interview-II(OPHI-II), Occupational Self Assessment(OSA), The Occupational Circumstances Assessment Interview and Rating(OCAIR) assessment were conducted on elderly person with dementia. Further interviews were conducted with case manager and family. Results : After interviews and assessments were conducted, the results of which showed limitations in social and family relationship, financial issues, general well-being. Conclusion : Applying the MOHO forms a basis for judging the subject in a holistic and general way, changes how the subject is viewed, suggests various strategies. For improving the professinoalism and qualities of occupational therapy service, and may help expand the range of other relevant areas.

• Journal of Internet Computing and Services
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• v.9 no.6
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• pp.155-163
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• 2008

Project Monitoring and Control is one of the required activities in project management. This activity provides the information about whether a project is making a progress as it is planned. It is usually performed in weekly meetings or milestone meetings where the project manager checks the project's current status based on project measures such as schedule, cost and work performance. One of the popular method for project monitoring and control is EVM(Earned Value Management). The major characteristic of EVM is that it uses only one measure 'cost' for schedule and work performance so that it enables 2 independent graphs to be illustrated in one integrated graph based on cost. For applying EVM to a project, it is essential to break whole work to work packages and to assign value of cost to each work package at the initial stage of the project. Therefore EVM is well matched with the lifecycle which requires whole plan at the beginning of project. However, in XP(eXtreme Programming), whole customer requirements are difficult to define and to make a complete plan at the beginning and are more detailed in each Iteration. Therefore EVM is not comfortable method for XP. Therefore in this research we suggest 3 layer EVM which can be applied in XP, and develop a process guidelines based on CMMI(Capability Maturity Model Integration) PMC(Project Monitoring and Control) process area.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.655-661
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• 2017

It is a very important task to extract character regions contained in various input color images, because characters can provide significant information representing the content of an image. In this paper, we propose a new method for extracting character regions from various input images using MCT features and an AdaBoost algorithm. Using geometric features, the method extracts actual character regions by filtering out non-character regions from among candidate regions. Experimental results show that the suggested algorithm accurately extracts character regions from input images. We expect the suggested algorithm will be useful in multimedia and image processing-related applications, such as store signboard detection and car license plate recognition.

• The Journal of the Korea Contents Association
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• v.7 no.2
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• pp.109-116
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• 2007

To reduce the effect of color distortions on reading colors, it is more desirable to statistically process as many pixels in the individual color region as possible. This process may require segmentation, which usually requires edge detection. However, edges in color codes can be disconnected due to various distortions such as dark current, color cross, zipper effect, shade and reflection, to name a few. Edge linking is also a difficult process. In this paper, k-means clustering was performed on the images where edge detectors failed segmentation. Experiments were conducted on 311 images taken in different environments with different cameras. The primary and secondary colors were randomly selected for each color code region. While segmentation rate by edge detectors was 89.4%, the proposed method increased it to 99.4%. Color recognition was performed based on hue, a*, and b* components, with the accuracy of 100% for the successfully segmented cases.

• Journal of Broadcast Engineering
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• v.6 no.2
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• pp.169-176
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• 2001

Most of the previous video watermarking algorithms cannot be supported by real-time video processing. The maul reason is that in order to develop a robust algorithm the watermarking technique requires a very high computational cost when embedding and extracting the watermark in various frequency domains. Previous embedding methods simultaneously try to compress a video by MPEG and embed a watermark supporting real-time processing. However, In this paper, our proposed algorithm can support real-time processing in both spatial and frequency domains. First. the watermark is created on the courier transform domain, and next is inverse-Fourier-transformed ; then, we directly embed it into the video frame In the spatial domain. This procedure does not require a lot of the computational cost during embedding because of the spatial domain processing. Also, it is possible to support a video stream service and a very robust algorithm from MPEG compression and various geometric attacks.