• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.14 no.2
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• pp.181-188
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• 1996

Geodetic Satellite Positioning Techniques (NNSS, Transit, Doppler, VLBI, SLR etc.) still have much difficulty in surveying and necessity of point positions is being amplified in korea. Therefore some research institutes have being investigated point positioning using the GPS. In this study, 1 arranged the theory deal with point positioning using GPS carrier beat phase of dual frequency and estimated corrections of errors that be included in GPS observable. Also, 1 determined point position by the differencing scheme of GPS carrier phase, and analyzed the accuracy of point position. 1 suggested potentiality of geodetic point positioning using GPS carrier phase by comparing result of relative positioning with result of point positioning and analyzing result of network adjustment fixed any point position.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.2 no.2
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• pp.1-13
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• 1984

Projection has been used in order to indicate the horizontal position of triangulation stations which had been existed on the earth surface. In our country, the plane Rectangular coordinate of the triangulation station is computed by means of Gauss Double projection. But it proves to contain many errors according to the difference in Latitude and longitude. Therefore, in this study Transverse Mercator projection which is known to contain less error than Gauss Double projection in an applied region is introduced, and the results obtain by two these projections and the value today in our country are compared and analysed. when an another plane Rectangular Coordinate system is added to the present 3-plane Rectangular Coordinate system, there is an object inshowing the best position.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.1
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• pp.1-8
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• 2018

To compensate for the shortcomings of spirit leveling, research on the determination of GNSS (Global Navigation Satellite System)-derived orthometric height has been actively carried out. However, most analyses were primarily performed inland. In this study, the influences of the arrangement of control points, observation duration, and geoid model on the accuracy of the GNSS-derived orthometric height have been analyzed to suggest the proper method to apply the determination of GNSS-derived orthometric height to the leveling loop disconnected area. As a result, it was found that two known points located near the unknown points need to be fixed in the leveling loop disconnected area. Further, 3 cm level of accuracy can be achieved if the GNSS survey is performed over two days, for four hours per day. In terms of the geoid model, the latest national geoid model should be applied rather than the EGM08 (Earth Gravitational Model 2008) to minimize regional bias and increase accuracy. Future research is necessary to apply the determination of the GNSS-derived orthometric height technique as a method to connect with the islands because the vertical reference system used inland and that used for the islands in Korea are still different.

• Korean Security Journal
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• no.8
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• pp.379-407
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• 2004

The cyber-crime is one of the results occurring from the increased dependency toward information-telecommunication devices. Currently, the Korean National Police Agency and many other related law enforcement agencies have made efforts to respond against the cyber-crimes. However, the number of cyber-crime is increasing steadily. The worse problem is that the arresting rate for the cyber-crime has been decreased than before. The reasons of decreasing arresting rate come from many different kinds of cyber-crime methods with the developed computer and network technology, Also, the easy concealment of the cyber-crime by the violater and the difficulty of specification against the data objected to search and seizure make the crackdown difficult. The other difficulties come from the lack of professionally trained investigators, the lack of high-technological investigation devices, and the failure of the technology development for the search and seizure of evidences because of the budget deficit. That is to say, these phenomenon show the comprehensive problem of the cyber-police system. Accordingly, to respond against newly changed cyber-crime activities and to investigate effectively, the cyber-police has to take consideration into the professional reorganization of the cyber-police, the development of the investigation technology, and the adjustment of current cyber-crime laws. Most importantly, the cyber-police needs the high-technological investigation devices, the development of the investigation methods, and the training for the professional human resources with the enough budget support.J

• Journal of the Korean Institute of Intelligent Systems
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• v.13 no.2
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• pp.180-185
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• 2003

This paper proposes an intelligent navigation algorithm for multiple mobile robots under unknown dynamic environment. The proposed algorithm consists of three basic parts as follows. The first part based on the fuzzy rule generates the turning angle and moving distance of the robot for goal approach without obstacles. In the second part, using both fuzzy and neural network, the angle and distance of the robot to avoid collision with dynamic and static obstacles are obtained. The final adjustment of the weighting factor based on fuzzy rule for moving and avoiding distance of the robots is provided in the third stage. The experiments which demonstrate the performance of the proposed intelligent controller is described.

• Journal of the Economic Geographical Society of Korea
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• v.16 no.1
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• pp.17-36
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• 2013

The purpose of this study examines interaction between region and industries through industrial networks of the regional resource-based industry. To achieve this goal, the fermented soy products industry in Sunchang is selected as a case study. This study traces the process of adjustment of firm-activity networks. And then, it scrutinizes the coevolution process between region and industry. It shows that the fermented soy products industry in Sunchang is embedded in the region and it strengthens regional development potentials for the local/regional economy.

• Journal of Korea Game Society
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• v.20 no.4
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• pp.77-88
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• 2020

Recently, interest in game streaming is high in cloud-based gaming. In game streaming, remote game servers perform graphics rendering and stream the resulting scene images to clients' device on the Internet. We model the client-server allocation (CSA) problem for balancing the GPU load between servers in a game streaming environment as an optimization problem, and propose a simulated annealing-based method. The features of our method are that the method takes into account the constraints on network delay and has the ability to automatically adjust the frame rate of game sessions if necessary.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.1036-1041
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• 1997

The objective of this study is to adjust the roll gap for the dimension accuracy of bar in hot bar rolling process considering roll wear. In this study hot bar rolling processes for round and oval passes have been investigated. In order to predict the roll wear, the wear model is reformulated as an incremental form and then wear depth of roll is calculated at each deformation step on contact area using the results of finite element analysis, such as relative sliding velocity and normal pressure at contact area. Archard's wear model was applied to predict the roll wear. To know the effects of thermal softening of DCI (Ductile Cast Iron) roll material according to operating conditions, high temperature micro hardness test is executed and a new wear model has been proposed by considering the thermal softening of DCI roll expressed in terms of the main tempering curve. The new technique developed in this study for adjusting roll gap can give more systematically and economically feasible means to improve the dimension accuracy of bar with full usefulness and generality.

• IE interfaces
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• v.22 no.3
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• pp.252-262
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• 2009

It is crucial to prevent low yields in the semiconductor industry. Since many factors affect variation in yield and they are deeply related, preventing low yield is difficult. There have been substantial researches in the field of yield prediction. Many researchers had used the statistical methods. Many studies have shown that artificial neural network (ANN) achieved better performance than traditional statistical methods. However, despite ANN's superior performance some problems such as over-fitting and poor explanatory power arise. In order to overcome these limitations, a relatively new machine learning technique, support vector machine (SVM), is introduced to classify the yield. SVM is simple enough to be analyzed mathematically, and it leads to high performances in practical applications. This study presents a new efficient classification methodology, Stepwise-SVM (SSVM), for detecting high and low yields. SSVM is step-by-step adjustment of parameters to be precisely the classification for actual high and low yield lot. The objective of this paper is to examine the feasibility of SVM and SSVM in the yield classification. The experimental results show that SVM and SSVM provides a promising alternative to yield classification for the field data.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39B no.2
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• pp.61-74
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• 2014

In recent years, development of femtocells are receiving considerable attention towards increasing the network coverage, capacity, and improvement in the quality of service for users. In 3GPP LTE-Advanced (LTE-A) system, to efficiently utilize the bandwidth, femtocell and macro cell uses the same frequency band, but this deployment poses a technical challenge of cross-tier interference to macro users. In this paper, the novel quality of service based fractional power control (QoS-FPC) scheme under the heterogeneous networks environment is proposed, which considers the users priority and QoS-requirements during the power allocation. The proposed QoS-FPC scheme has two focal points: firs, it protects the macrocell users uplink communication by limiting the cross-tier interference at eNB below a given threshold, and second, it ensures the optimization of femtocell users power allocation at each power adjustment phase. Performance gain is demonstrated with extensive system-level simulations to show that the proposed QoS-FPC scheme significantly decreases the cross-tier intereference and improves the overall users throughput.