• Journal of Korean Society on Water Environment
• /
• v.34 no.6
• /
• pp.678-687
• /
• 2018

The purpose of this study was to understand the unique and complicated feature of urban stream receiving various inflows. The Yangjae stream, the second tier of the Han River, runs through the southern parts of Seoul, Korea and its middle part flows on the boundary of Seoul where land use is actively changing. Stream flow was greatly influenced by rainfall. Other than rainfall events, effluent discharge from wastewater treatment plant (WWTP) comprised 51 % of stream flux. As a result, majority ions water chemistry was changed at the receiving zone of the discharged effluent (Zone A). Its contribution increased to 69.9 % at the second sampling period with low stream flow. In the middle zone, inflows from the northern area, recently developed to a residential district showed low $NO_3-N$ and high $HCO_3$, Ca, $SO_4$, and $SiO_2$ indicating the effects of groundwater and concrete. One inflow (T-8), with extremely high Na and Cl, median $SiO_2$, was assessed to have anthropogenic influence, however its contribution to main stream was under 1 %. Road construction near Y-13 also affected water chemistry leading to the highest Na and Cl concentration. These hydro chemical changes can be critically used to evaluate the changes in water budget and fate of chemicals in a peri-urban watershed occasioned by human activities on the Yangjae.

• Journal of Korean Critical Care Nursing
• /
• v.15 no.2
• /
• pp.1-13
• /
• 2022

Purpose : The study aimed to identify relationship among intensive care unit (ICU) nurses' critical thinking disposition, medication error risk level of high-alert medication, and medication safety competency, as well as the factors affecting medication safety competency. Methods : The participants were 266 ICU nurses of one higher-tier general hospital and one general hospital in Province. The data were collected using structured self-administered questionnaire from August 10 to August 31, 2021. Measurements included the critical thinking disposition questionnaire, nurses's knowledge of high-alert medication questionnaire, the medication safety competency scale. Data were analyzed using hierarchical multiple regressions using SPSS/WIN 28.0. Results : In the multiple regression analysis, the medication safety competence has a statistically significant correlation with the working department, the critical thinking disposition, and medication error risk level of high-alert medication. Conclusion : Based on the results of this study, it is suggested to develop and apply an educational strategy that can strengthen the knowledge and skills of critical thinking disposition and medication error risk level of high-alert medication to improve the ICU nurse's medication safety competency.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38A no.5
• /
• pp.451-458
• /
• 2013

This paper proposes a cross-tier interference avoidance scheme to improve femtocell performance in single frequency heterogeneous cellular networks (SFHCN). The scheduled macrocell users located close femtocell base stations cause serious interference to those femtocells so that the performance of femtocell is dramatically deteriorated. To solve this problem, this paper proposes an interference avoidance scheme by reversing the uplink and downlink frames of such femtocells. After reversing the uplink and downlink frames, femtocell base station relays the macrocell user data as well as transmitting its own data. In the 1st relaying link, femtocell and macrocell users transmit their data respectively divided uplink frames and in the 2nd relaying link, femtocell base station transmit macrocell and femtocell data using a simultaneously superposition coding scheme. Computer simulation results confirm performance improvement of proposed scheme.

• Applied Science and Convergence Technology
• /
• v.24 no.5
• /
• pp.136-141
• /
• 2015

We studied the compact anode design to develop 100 kW rotating anode X-ray tube with large focal spot 1.2 mm, small focal spot 0.6 mm and tube voltage 150 kV for large hospital digital radiography using computer thermal simulation. The larger thermal radiation effect in a high vacuum can reduce the temperature of anode so the method to increase the surface area of anode is investigated. The anode has the multi-tier shape at the back side of TZM body of anode and also bigger diameter of anode. The number of multi-tiers was varied from 6 to 15 and the diameter of anode was also varied from ${\Phi}74$ to ${\Phi}82$. From ANSYS transient thermal simulation result, we could obtain $1056.4^{\circ}C$ anode maximum temperature when applying 100 kW input power at 0.1 second on target focal track which is less than $1091^{\circ}C$ of the conventional 75 kW X-ray tube with reduced anode weight by 15.5% than the conventional anode. The compact anode of reduced anode weight is able to improve the unwanted noise when the rotor is rotating at high-speed and also reduce the rotational torque which the cost effective stator-coil is possible. It is believed that the anode with 15 ea multi-tiers using ${\Phi}82$ can satisfy with the specification of the anode heat capacity. From the results of this paper, it has been confirmed that the proposed compact anode can be used as the anode of 100 kW rotating anode X-ray tube for digital radiography.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.15 no.4
• /
• pp.105-117
• /
• 2015

In this paper, we consider 19 cells with the two tiers for polar-rectangular coordinates (PRCs) and provide the cell edge performance of cellular networks based on distance from cell center i.e., BS (base station). When FFR is applied(or adopted) to cell edge, it is expected that BS cooperation, or a coordinated multipoint (CoMP) multiple access strategy will further improve the system performance. We proposed a new method to evaluate the sum rate capacity of the MIMO DC of multicell system. We improve the performance of cell edge users for intercell interference cancelation in cooperative downlink multicell systems. Simulation results show that the proposed scheme outperforms the reference schemes, in terms of cell edge SINR (signal-to-interference-noise ratio) with a minimal impact on the network path loss exponent. We show 13 dB improvements in cell-edge SINR by using reuse of three relative to reuse of one. BS cooperation has been proposed to mitigate the cell edge effect.

• Journal of the Korean Geosynthetics Society
• /
• v.4 no.2
• /
• pp.29-38
• /
• 2005

It is essential to take consideration of long-term deformation characteristics of mechanically stabilized earth wall user sustained and repeated loads for design and construction, especially for use as part of permanent structures. This paper presents the long-term performance of a full-scale geogrid reinforced segmental retaining wall results based on the measured strains in geogrids for three years. The results indicate that the reinforcement tensile strains tend to continuously increase after wall completion with the increase being more pronounced in the reinforcement layers in the lower tier. It can be concluded that the long-term deformation should be taken in account for walls constructed as part of permanent structures for which wall deformation should be controlled.

• Journal of Korea Multimedia Society
• /
• v.2 no.4
• /
• pp.476-489
• /
• 1999

HW/SW codesign is integrated design of systems implemented using both hardware and software components. Many design tools has been developed to support this new paradigm, so far. Current codesign tools are not widely used as been expected because of variety problems - rapidly evolving technology, platform dependency, absence of standard specification method, inconsistent user interface, varying target system, different functionality In this paper, we propose a web-based distributed HW/SW codesign environment to remedy this kinds of problem. Our codesign environment has object-based 3 tier client/server architecture. It supports collaborative workspace through session service. Fully object-oriented design of user interface(OOUI) enables easy extension without change of user Interface. Furthermore it contains transaction server and security server for efficient and safe transfer of design data. To show a validity of our design, we developed prototype of web-based HW/SW codesign environment called WebCEDA. Our model of HW/SW codesign can be used for web-based generic CAD tools.

• Journal of Korean Society of Rural Planning
• /
• v.3 no.1
• /
• pp.54-67
• /
• 1997

Korean societies have been experiencing the wholesale structural changes in the rapid currents of recent openness, globalization and democratization, which effect much more heavily in rural areas than in urban areas, so rural recomposition works being an important national concern. In order to systematically reconstruct the rural structure, the decision makers, with a four step hierarchy of rural resident-residents group-community-region, should be endowed with the objective judgement on basic elements of resource potentialities under their control. In this process. rational resource evaluation works would be firstly necessiated from expert groups. Based on the view mentioned above, this study principally aimed at developing a rational evaluation framework for rural resources. For that objective, the first step of the study pigeonholed the total resources items identifiable in rural areas from the existing study results, spatial planning and field surveying data. After then, using the formalized classification criteria of resources items, a tentative goal system for rural resources evaluation was proposed and the final one determined through expert-group checking. The results obtained during the study are summarized as follows ; 1. Using the existing examples of resources identification/classification and the basic data list for county-level development planning as the principal reference ones, total rural resources elements were classified into 3 constituent units : land, natural environment and human resources, which correspond to places to work, to play and to live, respectively, as 3 constituent ones of life-supporting space. 2. Three characteristic areal types were adopted to represent the total rural areas : lowland, upland and seashore areas, and also 3 practical use types to represent the objectives of resources evaluation systems : for land use planning, natural conservation policy and village improvement planning. Thus 9 different types of goal system for resources evaluation were developed(each system by 3 areal typesX3 practical use types) 3. Each goal system has 3-tier classification steps from the higher, middle and lower one. The higher and middle steps should contain equally applicable components to all the rural areas, of which allowable number being around 3 and 4 respectively. However the lower step would contain detailed sub-components changeable to areal characteristics of which allowable number being around 7.

• Journal of architectural history
• /
• v.17 no.3
• /
• pp.7-21
• /
• 2008

Three-story Stone pagodas in Gameunsa Temple site, one of the early staged stone pagodas, has been known as a standard of Silla stone pagodas. A stone pagoda is not only a stone art work and but also a stone architecture. In understanding the stone pagoda it is very important to be approached with technological side in which we can investigate the stone pagoda deeply and as well as to have been approached with art historical view. Also it needs that we should see the stone pagoda in view of structural safety. We can get many high technique from our ancestors who made Gameunsajiseoktap. 1. To reduce any deformation such as relaxation and sinking of members which is caused by a heavy load the members such as the lower tier of the base is made up of the foundation stone and side stone in each, comprising one stone. 2. A special construction method for connection between wall stone and column stone in stereobates was invented. It is to make column stone projected partially and wall stone be caved in that two members should be jointed well. This unique method is not used any longer after the three-story Stone pagodas in Gameunsa Temple Site. 3. In each side upper and lower member are not engaged as the size of roof stones and support stones of roof stones are different. It can be done for a distribution of perpendicular load and a prevention for relaxation of members. 4. It makes sure that to make upper ends of support stones 10mm lower was to be avoid upper loads to it judging from survey in disassemblying east pagoda. It proves that ancestors who made this stone pagoda had a technique to understand the structural matters to make small members as big as possible, not to engage in joint, to avoid in ends of members from upper load.

• The Journal of Korean Association of Computer Education
• /
• v.7 no.2
• /
• pp.25-34
• /
• 2004

Sixteen provincial Research Institute of Education and Science(RISE) in the country have provided good qualified multimedia educational materials that was produced by some special skilled teachers to elementary, middle and high school teachers using web services. And moreover KERIS and KICE have also produced educational materials and have a plan to integrate distributed multimedia educational materials that RISE produced. The development of KERIS's KEM metadata in 2001 and the making of educational material metadata of RISE is the first step of integration plan. These metadata can be used to make integration plan possible. But before taking integration plan, the study of how to integrate and manage it should be performed. Therefore, this paper introduces the technique of XML web service and JDBC with 3-tier system as the method of integrate distributed educational material metadata. The evaluation shows these two methods have similar response time with MS SQL Server 2000 and Oracle 9i. Thus, we conclude that JDBC and XML web service can be the proper solution to search XML-formatted metadata.