• Journal of the Korea Society of Computer and Information
• /
• v.21 no.1
• /
• pp.73-78
• /
• 2016

In wireless sensor networks, sensors have capabilities of sensing and wireless communication, computing power and collect data such as sound, movement, vibration. Sensors need to communicate wirelessly to send their sensing data to other sensors or the base station and so they are vulnerable to many attacks like garbage packet injection that cannot be prevented by using traditional cryptographic mechanisms. To defend against such attacks, a behavior-based attack detection is used in which some specialized monitoring nodes overhear the communications of their neighbors(normal nodes) to detect illegitimate behaviors. It is desirable that the total sensing area of normal nodes covered by monitoring nodes is as large as possible. The previous researches have focused on selecting the monitoring nodes so as to maximize the number of normal nodes(node coverage), which does not guarantee that the area sensed by the selected normal nodes is maximized. In this study, we have developed an algorithm for selecting the monitoring nodes needed to cover the maximum sensing area. We also have compared experimentally the covered sensing areas computed by our algorithm and the node coverage algorithm.

• Journal of Environmental Impact Assessment
• /
• v.4 no.1
• /
• pp.59-64
• /
• 1995

Environmental Impact Assesment(EIA) is composed of various procedures, such as screening, scoping, inventory survey, prediction, assessment, mitigation measure, alternative assessment, and post management. Remote sensing introduced lately begins to be applied ecosystem and land use in inventory survey and assessment of EIA. This study explains on land use classification, buffering analysis of residential area, and overlaying analysis of odor predictive data with residential area for application to EIA with remote sensing data. Residential area extracted from land use classification of remote sensing provides effectively buffering analysis of residential area in selection of landfill site with GIS. It could assess also residential effect to an offensive odor by overlaying analysis. Application methods in EIA should be enlarged to assess effectively.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2013.02a
• /
• pp.653-653
• /
• 2013

In this study, ITO extended gate reduced graphene oxide field effect transistor (rGO FET) was demonstrated as a transducer for a proton sensing application. In this structure, the sensing area is isolated from the active area of the device. Therefore, it is easy to deposit or modify the sensing area without affecting on the device performance. In this case, the ITO extended gate was used as a gate electrode as well as a proton sensing material. The proton sensing properties based on the rGO FET transducer were analyzed. The rGO FET device showed a high stability in the air ambient with a TTC encapsulation layer for months. The device showed an ambipolar characteristic with the Dirac point shift with varying the pH solutions. The sensing characteristics have offered the potential for the ion sensing application.

• Proceedings of the KSRS Conference
• /
• 2003.11a
• /
• pp.1337-1339
• /
• 2003

In this article, a new remote sensing image fusion model based on modified Kohonen networks is given. And a new fusion rule based on modified voting rule was established. Select Shaoxing City as the study site, located at Zhejiang Province, P.R.China. The fusion experiment between Landsat TM data (30m) and IRS-C Pan data (5.8m) was performed using the given fusion method. The fusion results show that the new method can gain better result in apply ing to the lower hill area, and the whole classification accuracy was 10% higher than the basic Kohonen method. The confusion between the woodlands and the waterbodies was also diminished.

• Atmosphere
• /
• v.33 no.2
• /
• pp.197-222
• /
• 2023

Remote sensing becomes a new and core framework for the atmospheric sciences and closely related areas concerning with the ever-changing global environmental status. However, remote sensing in the Korea Meteorological Society is relatively new, where the first relevant paper is appeared in 1983, as well as is an area with relatively limited number of research groups. Here, we review and summarize some of the key progress in this area within Korea Meteorological Society focusing on the areas of satellite, radar, and ground based remote sensing such as lidar, spectrometer and sun photometer. Overall, the area is shown to have the most significant progress occur along with the acquisition of the key infra structures such as the COMS (Communication, Ocean and Meteorological Satellite) and S-band radar system led by Korea Meteorological Administration in early 2000. After that, the area has quickly developed into a status playing important roles to lead and support the overall activities in the atmospheric measurements. It is expected that the importance and role of the remote sensing will increase in the coming years.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.46 no.5
• /
• pp.25-31
• /
• 2009

The recently developed sampling theory, "compressed sensing" is gathering huge interest in MR reconstruction area because of its feasibility of high spatio-temporal resolution of dynamic MRI which has been limited in conventional methods based on Nyquist sampling theory. Since dynamic MRI usually has high redundant information along temporal direction, this can be very sparsely represented in most of cases. Therefore, compressed sensing that exploits the sparsity of unknown images can be effectively applied in most of dynamic MRI. This review article briefly introduces currently proposed compressed sensing based dynamic MR imaging algorithms and other methods exploiting sparsity. By comparing them with conventional methods, you may have insight how the compressed sensing based methods can impact nearly every area of clinical dynamic MRI.

• Korean Journal of Remote Sensing
• /
• v.8 no.2
• /
• pp.105-123
• /
• 1992

A study was made on the feature extraction for non-metallic one deposits and their related geology using the Remote Sensing and Airborne Radiometric data. The area chosen is around the Haenam area, where dickite and Quarzite mines are distributed in. The geology of the area consists mainly of Cretaceous volcanics and PreCambrian metamorphic. The methods applied are study on the reflectance characteristics of minerals and rocks sampled in the study area, and the feature extraction extraction of histogram normalized images for Landsat TM and Airborne Radiometric data, and finally evaluation of applicability of some useful pattern recognition techniques for regional lithological mapping. As a result, reflectances of non-metallic minerals are much higher than rock samples in the area. However, low grade dickites are slightly higher than rock samples, probably due to their greyish colour and also their textural features which may scatter the reflectance and may be capable of capturing much hychoryl ions. The reflectances of rock samples may depend on the degree of whiteness of samples. The outcrops or mine dumps in the study area were most effectively extracted on the histogram normalized image of TM Band 1, 2 and 3, due to their high reflectivity. The Masking technique using the above bands may be the most effective and the natural colour composite may provide some success as well. The colour composite image of PCA may also be effective in extracting geological features, and airborne radiometric data may be useful to some degree as an complementary tool.

• Proceedings of the KSRS Conference
• /
• 2003.11a
• /
• pp.846-848
• /
• 2003

Analysis of UHI in Busan region using Landsat TM data. Between 1987 and 1997 surface temperature increased clearly. Land usage of Busan is construed that instigate UHI changing into industry and commerce area. Also, intensity of UHI in surface temperature appeared strongly in industrial area and business area. On the contrary, residential area, mountain area, suburb area did not appear strongly.

• Korean Journal of Remote Sensing
• /
• v.24 no.6
• /
• pp.621-629
• /
• 2008

This study was carried out in part of Tamil Nadu, India. Also, Landsat ETM+ image and field sampling data were acquired. The field data were basal area, number of trees and number of species. Using the data set, this study performed a three steps processing, (1) Image classification (2) extracting the vegetation indices(NDVI, Tasseled cap brightness, greenness and wetness) (3) mapping the prediction of biodiversity distribution using basal area and NDVI image value. Basal area was significantly correlated with NDVI. The result of classification showed 69% overall accuracy.

• Journal of Institute of Control, Robotics and Systems
• /
• v.18 no.4
• /
• pp.321-327
• /
• 2012

This paper presents a comparative analysis on three different types of performance indices of obstacle detection for an overlapped ultrasonic sensor ring. Due to beam overlap, the entire sensing zone of each ultrasonic sensor can be divided into three smaller sensing subzones, which leads to significant reduction of positional uncertainty in obstacle detection. First, the positional uncertainty in obstacle detection is expressed in terms of the area of a sensing subzone, and type 1 performance index is then defined as the area ratio of side and center sensing subzones. Second, based on the area of a sensing subzone, type 2 performance index is defined taking into account the size of the entire range of obstacle detection as well as the degree of the positional uncertainty in obstacle detection. Third, the positional uncertainty in obstacle detection is now expressed in terms of the length of the uncertainty arc spanning a sensing subzone, and type 3 performance index is then defined as the average value of the uncertainty arc lengths over the entire range of obstacle detection. Fourth, using a commercial low directivity ultrasonic sensor, the changes of three different performance indices depending on the parameter of an overlapped ultrasonic sensor ring are examined and compared.