• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.24 no.2
• /
• pp.201-208
• /
• 2006

Currently, 1/5,000 Digital Topographic Map covers the whole country with administrative boundary of Gu, while some region has already been constructed with 1/1,000 digital topographic map has legal boundary of Dong. Here, Dong in 1/1,000 scale represents the legal boundary which is used in the address most of time. Therefore, there is no administrative-Dong yet although it is very useful in various fields. In this study, we suggested a method to construct the administrative boundary extending to the level of Dong empirically. In addition, the practical application of the administrative boundary in GIS is discussed. Two methods are applied to construct the administrative boundary to the level of administration-Dong; using the edited cadastral map and the digital topographic map. When the edited cadastral map is used, some problems such as boundary discordance to superordinate administrative area is appeared. On the other hand, using digital topographic map showed simple construction processes and easy connection with other framework data. Therefore, it is recommended that the digital topographic map should be used in the construction of the administrative boundary. It would be useful as framework data in various industries and public operations.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.15 no.6
• /
• pp.59-69
• /
• 2005

Ad hoc network is the network which can be considered without a pre-constructed infrastructure, and a mobile node can join the network freely. However, the participation of the mobile nodes to the ad hoc network brings up much burden of re-computation for new routes, because it leads to losing the connection frequently. And, also, it causes serious security problem to be broadcasted wrong information by the malicious user. Therefore, it needs authentication against the mobile nodes. To make that Possible, we have two methods: single CA and distributed CA. In the case of CA method, the wireless network can be collapsed owing to expose the CA, but still the distributed CA method is a little more safe than previous one because it needs attacks toward a lot of CAs to collapse the network We can consider Secret Share scheme as the method that constructs the distributed CA system, but it is weak when the network size is too large. In this paper, we suggest hierarchical structure for the authentication method to solve this problem, and we will show the results of simulation for this suggestion.

• 한국신재생에너지학회:학술대회논문집
• /
• 2010.11a
• /
• pp.42.2-42.2
• /
• 2010

Transparent conducting oxides (TCOs) are of significant importance for their applications in various devices, such as light-emitting diodes, thin-film solar cells, organic light-emitting diodes, liquid crystal displays, and so on. In order for TCOs to contribute to the performance improvement of these devices, TCOs should have high transmittance and good electrical properties simultaneously. Sn-doped $In_2O_3$ (ITO) is the most commonly used TCO. However, indium is toxic and scarce in nature. Thus, ZnO has attracted a lot of attention because of the possibility for replacing ITO. In particular, group III impurity-doped ZnO showed the optoelectronic properties comparable to those of ITO electrodes. Al-doped ZnO exhibited the best performance among various doped ZnO films because of the high substitutional doping efficiency. However, in order for the Al-doped ZnO to replace ITO in electronic devices, their electrical and optical properties should further significantly be improved. In this connection, different ways such as a variation of deposition conditions, different deposition techniques, and post-deposition annealing processes have been investigated so far. Among the deposition methods, RF magnetron sputtering has been extensively used because of the easiness in controlling deposition parameters and its fast deposition rate. In addition, when combined with post-deposition annealing in a reducing ambient, the optoelectronic properties of Al-doped ZnO films were found to be further improved. In this presentation, we deposited Al-doped ZnO (ZnO:$Al_2O_3$ = 98:2 wt%) thin films on the glass and sapphire substrates using RF magnetron sputtering as a function of substrate temperature. In addition, the ZnO samples were annealed in different conditions, e.g., rapid thermal annealing (RTA) at $900^{\circ}C$ in $N_2$ ambient for 1 min, tube-furnace annealing at $500^{\circ}C$ in $N_2:H_2$=9:1 gas flow for 1 hour, or RTA combined with tube-furnace annealing. It is found that the mobilities and carrier concentrations of the samples are dependent on growth temperature followed by one of three subsequent post-deposition annealing conditions.

• The Journal of Korean Academy of Prosthodontics
• /
• v.56 no.3
• /
• pp.212-217
• /
• 2018

Purpose: This study was to assess clinically the incidence of abutment screw loosening of posterior implant-supported fixed prosthesis and its affecting factors. Materials and methods: 391 implant-supported crowns restored from January 2013 to January 2016 were included in this study. All restorations were fabricated with either a single crowns or a splinted crown, and cemented with temporary cement. The incidence of abutment screw loosening is investigated and gender, restoration position, opposing teeth, restoration type, abutment connection type were assessed as possible factors affecting abutment screw loosening. Results: During the observation period (2 - 5 years), abutment screw loosening was found in 29 restorations (7.4%). It took 3 to 48 months (means 19.5 months) to loose the screw, and three of these implants were fractured. Among the factors considered, there were statistically significant differences at abutment screw loosening rate between molar group (9.4%) and premolar group (2.6%) (P<.019). According to the type of opposing teeth, there were statistically significant differences between nature teeth (74.7%) and implant (25.0%), removable denture (3%) (P<.019). The other possible factors did not have a significant effect on loosening of the abutment. Conclusion: The incidence of abutment screw loosening in posterior restoration was 7.4%. Abutment screw loosening were more likely to occur in molars group than premolar group, and according to the opposing teeth, there were the greatest frequency in nature teeth than implant and removal denture. There was a statistically significant difference.

• Journal of Gifted/Talented Education
• /
• v.15 no.2
• /
• pp.1-34
• /
• 2005

This study is composed of 2 parts. Study 1 empirically examined (1) the relationships among children's creative performances measured by three product-based assessments (story-telling, collage-making, and math word problems) in three domains, and (2) the relationships between children's general creative thinking skills, measured by two divergent thinking tests, and children's creative performances. Study 2 is a three-year follow up study of the study 1. Study 2 followed up some (71) children who participated in study 1. In study 2, long-term stability of the performance based assessment involving story-telling, collage making, and math problem making were examined during the three-year time period. In addition, study 2 tried to look at the methods effect of the domain issue of creativity, comparing self-report scale and performance-based assessment. The findings of this study support the position that creative ability in young children is rather (but not absolutely) domain-specific. The long-term stability of the performance-based assessments compares favorably with stability figures for other creativity tests. Results also indicate that there are some method effect in explaining the domain issue of creativity. Implication of the study in connection with educational practices for gifted children is discussed.

• The Journal of Engineering Geology
• /
• v.27 no.4
• /
• pp.377-382
• /
• 2017

Field experiments were conducted to estimate streambed hydraulic conductivity at 15 sites in the Anseongcheon watershed, Korea. Seepage meters and piezometers were installed in the streambed at each site to measure the amount of stream water-groundwater exchange and the hydraulic gradient. The vertical hydraulic conductivity was then calculated using Darcy's formula. The measured stream water-groundwater exchange rates were $4.08{\times}10^{-6}$ to $1.49{\times}10^{-5}m/s$, and the vertical hydraulic gradients were 0.005 to 0.145. The data suggest the streambed hydraulic conductivity to be $7.80{\times}10^{-5}$ to $1.58{\times}10^{-3}m/s$. The results show significant differences in connectivity between stream and aquifer. Quantification of the hydraulic interconnection between stream and aquifer, and evaluation of the effects of groundwater development and utilization on the streamflow require hydrogeological investigations of the connection between stream and aquifer, including the hydraulic conductivity of the streambed. Various field testing and analysis methods for hydrogeological assessment also require further improvement.

• Journal of the Korean Society for information Management
• /
• v.34 no.1
• /
• pp.341-371
• /
• 2017

Recently, the web service environment has changed from document-centered to data-oriented focus, and the Linked Open Data (LOD) exists at the core of the new environment. Specific procedures and methods were examined to build the LOD of records information in accordance with this trend. With the service sustainability of small-scale archive in consideration, an exemplification on LOD building process by utilizing open source software was developed in this paper. To this end, a 5-step service framework for LOD construction was proposed and applied to a collection of diary records from 'Human and Memory Archive'. Proof of Concept (POC) utilizing open source softwares, Protege and Apache Jena Fuseki, was conducted according to the proposed 5 step framework. After establishing the LOD of record information by utilizing the open source software, the connection with external LOD through interlinking and SPARQL search has been successfully performed. In addition, archives' considerations for LOD construction, including improvement on the quality of content information, the role of the archivist, were suggested based on the understanding obtained through the LOD construction process of records information.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.40 no.2
• /
• pp.334-348
• /
• 2015

Widespread use of smart devices accompanies increase of use of access point (AP), which enables the connection to the wireless network. If the appropriate security is not served when a user tries to connect the wireless network through an AP, various security problems can arise due to the rogue APs. In this paper, we are going to examine the threat by evil-twin, which is a kind of rogue APs. Most of recent researches for detecting rogue APs utilize the measured time difference, such as round trip time (RTT), between the evil-twin and authorized APs. These methods, however, suffer from the low detection rate in the network congestion. Due to these reasons, in this paper, we suggest a new factor, packet inter-arrival time (PIAT), in order to detect evil-twins. By using both RTT and PIAT as the learning factors for the support vector machine (SVM), we determine the non-linear metric to classify evil-twins and authorized APs. As a result, we can detect evil-twins with the probability of up to 96.5% and at least 89.75% even when the network is congested.

• Hwankyungkyoyuk
• /
• v.24 no.4
• /
• pp.111-128
• /
• 2011

This study was aimed at developing a common curriculum for the department of environmental education from 5 colleges of education. The need and background of curriculum reform can be summarized as follow; first, it has been recognized that new national curriculum of 2009 and 2011 created need for training teachers equipped with more integrated competency. Second, global environmental problems such as climate change and energy crisis asked for more responsible choice and action from all citizens. Third, the extremely low hiring rate resulted in the consideration of new working fields for teacher students majoring in environmental education. Fourth, the expansion of new environmental education paradigms including education for sustainable development called for practicing reconstruction of both contends and methods. From a series of research processes including analysis of current curriculum, DACUM, opinion survey and interest groups review, several new approaches for developing new curriculum had been identified as follow; first, content areas of environmental education should be extended beyond environmental natural science. Second, new learning approaches such as project-based learning need to be emphasized for strengthening the identity of environment as a separate subject. Third, more selective majoring system need to be applied in connection with environment government officials, researchers, and social environmental educators. It was recommended that the application of new curriculum developed by the study would be evaluated and managed by teaching conditions surrounding each of the five university members joined this developing processes. However, it needs to be noted that there is not much time because we had experienced zero hiring rate for the last 4 years and environmental policy and education programs are moving rapidly toward sustainable development.

• Clinical and Experimental Pediatrics
• /
• v.49 no.10
• /
• pp.1061-1066
• /
• 2006

Purpose : The purpose of this study was to research whether measurement of cow's milk specific IgE on the newborn would be helpful in the diagnosis of cow's milk allergy. We tried to find out the relation between cow's milk specific IgE and other allergy diseases by following up cases. Methods : We reviewed clinical features of 87 episodes in infants less than 4 weeks old who were positive in cow's milk specific IgE test. For the study group, history taking, physical examinations, elimination and cow's milk specific IgE tests were carried out. We investigated the connection among cow' milk specific IgE, allergic disease and family history in 40 of 87 patients we could follow up on. Results : The mean age of the study group was $17.2{\pm}5.4days$. The subjects were classified in four groups according into allergens : 87 milk allergy positive patients, 24 casein positive, 38 ${\alpha}$-lactoalbumin positive, and 75 ${\beta}$-lactoglobulin positive. The number of patients who had follow-ups for more than 6 months to was 40(45.9 percent). The patients whose parents had allergic disease numberred 10(25 percent). Fiften patients had allergic diseases, 4 had asthma and 11 atopic dermatitis. According to the follow-up study, there is a significant relation between casein positive patients and allergic disease. But there is no statistical and significant relation between cow's milk specific IgE and a family history of allergic disease. Conclusion : For the newborn babies, elimination tests and cow's milk specific IgE tests can be useful in the diagnosis of IgE-mediated or mixed milk allergies.