• Journal of the Korean Association of Geographic Information Studies
• /
• v.22 no.2
• /
• pp.1-14
• /
• 2019

In rural areas, composting is a source of non-point pollutants. However, as the quantitative distribution and loading have not been estimated, it is difficult to determine the effect of composting on stream water quality. In this study, composting datum acquired by unmanned aerial vehicle(UAV) was verified by using terrestrial LiDAR, and the management status and load change of the composting was investigated by UAV with manual control flight, thereby obtaining the basic data to determine the effect on the water system. As a result of the comparative accuracy assessment based on terrestrial LiDAR, the difference in the digital surface model(DSM) was within 0.21m and the accuracy of the volume was 93.24%. We expect that the accuracy is sufficient to calculate and utilize the composting load acquired by UAV. Thus, the management status of composting can be investigated by UAV. As the total load change of composting were determined to be $1,172.16m^3$, $1,461.66m^3$, and $1,350.53m^3$, respectively, the load change of composting could be confirmed. We expect that the results of this study can contribute to efficient management of non-point source pollution by UAV.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.29 no.4
• /
• pp.367-380
• /
• 2011

This paper has focused on deriving a GPS based geodetic network adjustment strategy to continuously determine coordinate sets of the national geodetic control points. After domestic literature review on the topic and overseas case studies about countries that recently reformed their geodetic infrastructure have been carried out, a simplified geodetic network consisting of two layers, namely GPS active and passive network, has been proposed to maximize effectiveness of the network adjustment through reducing the number of the passive points. Furthermore, a GPS data processing and network adjustment procedure has been derived to support the continuous management scheme. While a scheme for the active layer adopts a sequential least squares adjustment based on a multi-baseline, that of the passive layer employs a multi-session adjustment technique with respect to 3-dimensional baseline vectors. Finally, experimental adjustment against a network comprising 24 active and 6,900 passive stations has been performed to demonstrate the efficiency and the effectiveness of the proposed method.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.11 no.4
• /
• pp.133-141
• /
• 1991

The empirical method is used to integration adjustment for the coordinates revision of a national control point but the existing values are not to be changed or changed with small variation by suitable datum selection (for example, fixed points). This paper treats the modified weighted station parameter adjustment by quasi-observations, and the method used only variance elements of existing coordinates which is substituted for all covariance elements. The movement detection of unstable points and the junction adjustment of new networks are successfully executed by the method, in integration of new secondary networks to old-secondary-triangulation points which are in the absence of the original observations in Korea. The investigation results reveal that the accuracy of old-secondary-triangulation points is ${\pm}16^{{\prime}{\prime}}$(${\pm}0.08m$), which results from the densification of test network and the analyses of old survey specifications. and is ${\pm}2.3^{{\prime}{\prime}}$ in fixing of old-secondary-triangulation points.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.31 no.1D
• /
• pp.167-173
• /
• 2011

This paper analyzes the procedure of calculating how the results of national control points (triangulation points), based on Bessel datum, have been transformed into those of KGD2002, based on the world geodetic system. GPS and EDM data observed from 1974 to 2008 were used for this purpose. A large-scale integrated GPS network was constructed to estimate the results of KGD2002 and new national control points about 12,000 were decided through multiple stages of data processing. The accuracy of these results is ${\pm}0.015m$ (95%) in the horizontal direction and ${\pm}0.030m$ (95%) in the vertical direction. The adjusted results verified by the construction of an integrated GPS/EDM network were compared with the results of KGD2002. In conclusion, the bulletin results are thought to be appropriate because the coordinate differences (RMSE) are ${\pm}0.0025m$ and ${\pm}0.008m$ in horizontal and vertical directions respectively.

• Explosives and Blasting
• /
• v.22 no.3
• /
• pp.103-111
• /
• 2004

The existing methods that can be adopted for measuring joints involve either to use borehole or photogrammetry. Due to restricted space, acquisition of data in limited area, and measurement errors, above methods have limitations acquiring the objective and correct results. To get over defects of existing joint measurement methods, joints have been measured using 3D-Laser scanner with accuracy and efficiency. This research aims to investigate an accuracy and applicabiliy of 3D-Laser scanner for measuring rock slope joints. Measurement of rock slope joints has been executed using 3D-Laser scanner & clinometer and then, results from both methods are compared. Results from both methods indicate that they show nearly equal features for joint distributions and numbers of joint information obtained by 3D-Laser scanner are much more than ones measured using clinomer. Therefore, 3D-Laser scanner turns out to be very effective by the fact that it contributes to reduce investigation costs & periods, objectify data from rock slope joints.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.25 no.5
• /
• pp.437-449
• /
• 2007

This paper deals with issues of GPS network adjustment for the purpose of determining the $3^{rd}$ order national geodetic control points based on the Korean Geodetic Datum which has newly adopted in the country since early 2003. After examining and arranging all the observations, GPS baseline analyses were performed to estimate baseline vectors between two control points. All the observations were divided into 17 block networks in order to accelerate the adjustment efficiency. After applying a minimally constrained adjustment technique to each of the block networks for the sake of detecting outliers and examining network precision, over constrained adjustments by fixing all of the $2^{nd}$ order control points within the block network were carried out to derive final coordinate sets. The final solutions indicated that the accuracy of the adjusted coordinates was better than 1cm and 2cm in the horizontal and vertical component, respectively.

• The KIPS Transactions:PartA
• /
• v.14A no.4
• /
• pp.197-202
• /
• 2007

This study focused on design and implementation of Mobile 3D Bluetooth Game Engine based on OpenGL-ES. In Mobile 3D network game so far, there is a form the mainstream of wireless inter-net game using WAP and VM. But, VM game we popular because of an excessive communication expense problem for this mobile network game that occur when connect to wireless internet as point out to problem by it, that is, stand-alone game are very popular. This study introduce a mobile 3D Bluetooth Game Engine which is based on mobile 3D standard using OpenGL-ES to solve a problem like mobile network game generally that occur when connect to take pleasure a wireless internet from some people into a short distance. When the number of concurrent packet datum by Bluetooth terminal transfers to each other, we shows that the proposed scheduling scheme for enhancing the process speed up on Bluetooth.

• Journal of Elementary Mathematics Education in Korea
• /
• v.21 no.1
• /
• pp.73-92
• /
• 2017

A table as an effective arrangement tool of a set of data has not been focused on as a single research subject despite of the fact that the table has been clearly one of learning and teaching elements of national math curriculum for a long time. I hope this article gets to be a starting point for future studies of tables. For this, the Finland elementary mathematics textbooks which use tables so often for many various purpose are chosen and analysed. As a result, it confirms that tables can be practical tools for developing different mathematical ideas in mathematics textbooks. Its applicable area is not limited on statistics but numbers and operations, geometry, measurement, ratio and rate. In addition, some ideas of the outlook, the size and dimension of tables, and the context of datum and etc are induced from the Finland elementary mathematics textbooks.

• Journal of the Korean Society of School Health
• /
• v.4 no.1
• /
• pp.88-99
• /
• 1991

The purpose of this study was attempted to analyze the relationship between drug abuse and the other problem behavior Patterns among high school students in Cheju. In order to achieve these set-goals, questionaires were finally supplied to the total 379 case of 9 high school from October to December, 1990. The collected data were processed using the SPSS-X computer program and statistically analyzed by the Chi-square method and. percentage. Results of the study were as follows: Among the 370 adolescents, 32.4% of students experienced cigarette smoking in their life, adolescents who experienced alcohol drinking were 46.8%, 0.5% of the students ever used marihuana; cocaine 0.3%, stimulant 3.2%, hallucinogen and inhalants 0.5%, tranquilizer 1.4%, analgesics 31:6%, antitussives 6.5%, antihistamines 1.9%. And all students never experienced the amphetamines and narcotics. The rates of drug use except stimulant and antitussive were higher in the male than in the female students. For the analysis of personal identifying datum, the rates of experienced smokers increased among groups of buddhist and the rates of experienced alconoi drinking increased among groups of no religion. Drug abuser increased among the group lower socio-economic status student, the adolescents whose parents have traditional education point of view. And it was also higher in those who were living only one than in those who were living together. Most students tended to use drugs after 17 or 18 years old. Drug users were more inclined to commit other problem behaviors when compared non-drug users. In the conclusion of the above results, it will be necessary to investigate the drug problem of adolescent. Drug abuse of students must be seen in an environmental context including family, school, peer group and society and not solely as the characteristics of an individual adolescent. And their parents and teachers must be on the alert for the behavior changes of their children such as changes of school performance, neglecting homework, tardiness or truancy from school, runaway from home, and mingled with bad companions, etc. We must recognize that drug abuse is frequently symptomatic of problems in the adolescent's environment.

• Journal of IKEEE
• /
• v.19 no.3
• /
• pp.319-326
• /
• 2015

This paper proposes method about development of conversion software for controller without OPC stack to communicate with OPC DA client. The proposed method is composed of development of OPC server based on OPC DA standard protocol, development of GUI application can be checked the OPC tag and point informations, development of conversion module to convert from OPC protocol to open standard protocol. In the stage of development of OPC server based on OPC DA standard protocol, we develope server in the pc to transmit and receive datum through OPC DA protocol with OPC DA client. In the stage of evelopment of GUI application can be checked the OPC tag and point informations, run the OPC DA server and register to window system registry and check OPC tags, points, transmitting and receiving of data from serial communication. In the stage of development of conversion module to convert from OPC protocol to open standard protocol, convert from OPC tag data which has received from OPC DA client to protocol can be communicated with industrial controller using open standard protocol so that support to transmit and receive data. To evaluate the efficiency of the proposed software, we connected OPC DA server software and OPC client, and 5 sample industrial controller which use open standard protocol, as a result we got 96.98% average communication succeeding rate among entire transmitting and receiving packets. We also confirmed that successfully communicated between industrial building controller which uses modbus protocol and industrial OPC DA client using OPC DA conversion software proposed by this dissertation.