• Journal of Broadcast Engineering
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• v.13 no.6
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• pp.905-914
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• 2008

The paper studied the scheme of applying the MPEG-4 SVC signal to the Ka band satellite broadcasting system through the JSCC system to resolve the rain fading problem generated when providing the Ka band HDTV satellite broadcasting service. The Ka band satellite broadcasting system is based on the VCM mode of the DVB-S2, and the SVC signal is considered as one of the spatial scalability, the SNR scalability and the temporal scalability. The JSCC system jointed all the layers of the source coding system and the channel coding system, and allocated bit rate to source coding and channel coding for each layer to get the optimum receiving quality. The layers are consists of a base layer and an enhancement layer, and the bit rate of each layer is affected by the SVC signal. The applicability of the three SVC signals to the Ka band satellite broadcasting service is analyzed with respect to the rain fading, and the scheme of applying the most excellent SVC to the service is considered.

• Journal of Korean Society for Geospatial Information Science
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• v.10 no.4 s.22
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• pp.95-103
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• 2002

The accuracy of Digital Map does not meet the user's expectation, including the many errors caused while producing the project, this will be useless resulting waste of enormous national budget. To solve this Accuracy problem, clear regulations about the position accuracy of scaled Digital Map should be set immediately and provide the users with accurate information about Digital Map enabling the users to use Digital Map for each GIS application field. For this reason, the position accuracy evaluation of existing Digital Maps produced in diverse methods is on demand. In this study, therefore, we performed horizontal position survey of local selected Facilities Total Station equipment to evaluate the horizontal position accuracy of 1:1,000, 1:5,000 scaled Digital Map, obtained standard deviation using the results, performed T-Test to confirm the presence of bias and evaluated the position accuracy of Digital Map.

• Journal of Korean Society for Geospatial Information Science
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• v.13 no.4 s.34
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• pp.3-9
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• 2005

The extraction of traffic information based on image processing is under broad research recently because the method based on image processing takes less cost and effort than the traditional method based on physical equipment. The main purpose of the algorithm based on image processing is to extract vehicles from an image correctly. Before the extraction, the algorithm needs the pre-processing such as background subtraction and binary image thresholding. During the pre-processing much noise is brought about because roadside tree and passengers in the sidewalk as well as vehicles are extracted as traffic flow. The noise undermines the overall accuracy of the algorithm. In this research, most of the noise could be removed by extracting the exact road area which does not include sidewalk or roadside tree. To extract the exact road area, traffic lanes in the image were used. Algorithm speed also increased. In addition, with the ratio between the sequential images, the problem caused by vehicles' shadow was minimized.

• Journal of Korean Society for Geospatial Information Science
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• v.13 no.4 s.34
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• pp.39-46
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• 2005

This paper use virtual running after possible traffic capacity application for optimal route location. General road is designed the design after we examine an alternate adequacy investigation and an execution design sufficiently. Various road user's requirement must be reflected from the beginning. But it is difficult to contain the various suitable design criteria because we consider the existing 2-dimension element. First of all, this study chose optimal route, used traffic assignment and 3D simulation. Then selected optimal route through the consistent road construction by analyzing road driving simulation of 3-dimension data and the urban landscape. possible traffic capacity and virtual running will be able to do the urban landscape analysis harmonizing with the environment; equally, it could be objectively solve the problem of a civil appeal.

• Journal of Korean Society for Geospatial Information Science
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• v.7 no.2 s.14
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• pp.47-56
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• 1999

In this study, tie point observation in aerial triangulation was automated by the image processing methods. The technique includes boundary extraction and We matching processes. The procedures were applied to extract points of Interest and to find their conjugate points in the other images. The image coordinates of the identified points were then used to compute their absolute coordinates. An algorithm was developed in this study for the automation of observation in aerial triangulation, which is a manual process of selecting a tie point and recording the image coordinate of the selected point. The developed algorithm automates this process through the application of a mathematical operator to extract points of interest from an arbitrary image. The root m square error of image coordinates of the developed algorithm is $6.8{\mu}m$, which is close to that of the present analytical method. In a manual environment, the accuracy of the result of a photogrammetric process is heavily dependant on the level of skill and experience of the human operator. No such problem exists in an automated system. Also, as a result of the automated system, the time spent in the observation process could be reduced by a factor of 61.2%, thereby reducing the overall cost.

• Journal of Korean Society for Geospatial Information Science
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• v.20 no.2
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• pp.81-91
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• 2012

As the recent development of the ubiquitous computing environment, u-GIS is being highlighted as the core technology of the ubiquitous computing environment, and thereby, studies on spatio-temporal data are being actively conducted. In this u-GIS environment, it is still difficult for existing mobile devices to efficiently manage the massive spatio-temporal data of u-GIS that are increasing day by day. Therefore, this paper develops a spatio-temporal query processing system for mobile devices in order to solve the problem. The system provides various spatio-temporal operators to insert/delete/update/search spatio-temporal data and supports a query optimization function that uses a spatio-temporal index for the flash memory and a spatio-temporal histogram for guaranteeing query execution speed. Lastly, by applying the spatio-temporal query processing system developed in this paper to the virtual scenario, this paper has proved that the system can be utilized in various application fields necessary to process spatio-temporal data in the mobile environment.

• 한국공간정보시스템학회:학술대회논문집
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• 2004.05a
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• pp.75-82
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• 2004

Many researcher's efforts have made a significant advancement of space frame structure with various portion, and it becomes the most outsanding one of space structures. However, with the characteristics of thin and long term of spacing, the unstable behavior of space structure is shown by initial imperfection, erection procedure or joint, especially space frame structure represents more. This kind of unstable problem could not be set up clearly and there is a huge difference between theory and experiment. Moreover, the discrete structure such as space frame has more complex solution, this it is not easy to derive the formulation of design about space structure. In this space frame structure, the character of rise-span ratio or load mode is represented by the instability of space frame structure with initial imperfection, and snap-through or bifurcation might be the main phenomenon. Therefore, in this study, space frame structure which has a lot of aesthetic effect and profitable for large space covering single layer is dealt. And because that the unstable behavior due to variation of inner force resistance in the elastic range is very important collapse mechanism, I would like to investigate unstable character as a nonlinear behavior with a geometric nonlinear. In order to study the instability. I derive tangent stiffness matrix using finite element method and with displacement incremental method perform nonlinear analysis of unit space structure, star dome and 3-ring star dome considering rise-span $ratio(\mu}$ and load $ratio(R_L)$ for analyzing unstable phenomenon.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.6
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• pp.173-179
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• 2013

The traditional key exchange protocols are transmitted by using the cryptographic. However, these protocols are compromised by the attacker. To solve this problem, this paper proposes a key exchange protocol based on the steganography with the QR code. The steganography technique embed secret information to the images, documents, videos, and MP3 files and transmit to the others. The attacker can't know that the transmission data is the secret data. Therefore, the sender transmits efficiently and safely the secret data to the others. In additional, the cover image is using the QR code image to insert the secret key. If attackers scan the QR code, then they just read the information or connect URL. They can not be recognized that the QR code image is hiding the secret key. The experiments compare the QR code image with the well-known image about the distortion and the safety.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.10
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• pp.855-868
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• 2004

There are several types of singularities in controlling robotic manipulators: kinematic singularity, algorithmic singularity, semi-kinematic singularity, semi-algorithmic singularity, and representation singularity. The kinematic and algorithmic singularities have been investigated intensively because they are not predictable or difficult to avoid. The problem with these singularities is an unnecessary performance reduction in non-singular region and the difficulty in performance tuning. Tn this paper, we propose a method of avoiding kinematic and algorithmic singularities by applying a task reconstruction approach while maximizing the task performance by calculating singularity measures. The proposed method is implemented by removing the component approaching the singularity calculated by using singularity measure in real time. The outstanding feature of the proposed task reconstruction method (TR-method) is that it is based on a local task reconstruction as opposed to the local joint reconstruction of many other approaches. And, this method has dynamic task priority assignment feature which ensures the system stability under singular regions owing to the change of task priority. The TR-method enables us to increase the task controller gain to improve the task performance whereas this increase can destabilize the system for the conventional algorithms in real experiments. In addition, the physical meaning of tuning parameters is very straightforward. Hence, we can maximize task performance even near the singular region while simultaneously obtaining the singularity-free motion. The advantage of the proposed method is experimentally tested by using the 7-dof spatial manipulator, and the result shows that the new method improves the performance several times over the existing algorithms.

• Journal of Digital Contents Society
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• v.17 no.4
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• pp.279-286
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• 2016

Recently, the cosmetics industry considers male customers as a consumptive, active customer base who also have purchasing power with their stronger desire for their personal image enhancement. Male-preferred image brands have entered the era of unlimited competition through social media, thus increasing the acquisition of male beauty. Therefore, the information for designing favorable image strategies should be examined. This paper examines male awareness, determined by the degree of appearance management based on four categories (i.e., hair and skin care, makeup, foot and hand care, and plastic surgery). Based on the research, the paper proposes a data service to address the spatial and temporal separation problem between TV CF (the major media for recognizing information) and online $caf{\acute{e}}$/blog the major media for obtaining detailed information.