• Journal of Sensor Science and Technology
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• v.19 no.6
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• pp.497-503
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• 2010

This paper reports a chemomechanical explosive sensor based on a thin polymer membrane. The sensor consists of thin parylene membrane and electrodes. Parylene membrane is functionalized with 4-mercaptophenol which interacts strongly with nitrotoluene based explosives. The membrane deflection caused by molecular interaction between the surface and explosives is monitored by capacitance between the membrane and the substrate. To measure the capacitance, electrodes are formed on the membrane and the substrate. While the previous cantilever system requires a bulky optical measuring system, this purely electric monitoring method offers a compact and effective system. Thus, this explosive sensor can be readily miniaturized and used in the field. The developed sensor can reliably detect dinitrotoluene and its limit of detection is evaluated as approximately 110 ppb.

• Journal of the Korea Computer Industry Society
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• v.3 no.7
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• pp.953-956
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• 2002

The threat to the network is increasing due to explosive increasing use of the Internet. Current IDS(Intrusion Detection System) detects intrusion and does individual response in small area network. It is important that construction of infra to do response in all system environment through sharing information between different network domains. This paper provides a policy-based IDS management architecture enabling management of intrusion detection systems. The IIDS(Integrated Intrusion Detection System) is composed of IDAs(Intrusion Detection Agents). We describe requirements in design and the elements of function.

• Journal of Korea Society of Industrial Information Systems
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• v.8 no.1
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• pp.75-82
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• 2003

Computer and network security has recently become a popular subject due to the explosive growth of the Internet Especially, attacks based on malformed packet are difficult to detect because these attacks use the skill of bypassing the intrusion detection system and Firewall. This paper designs and implements a network-based intrusion detection system (NIDS) which detects intrusions with malformed-packets in real-time. First, signatures, rules in NIDS like Snouts rule files, are classified using similar properties between signatures NIDS creates a rule tree applying hashing technique based on the classification. As a result the system can efficiently perform intrusion detection.

• Journal of electromagnetic engineering and science
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• v.11 no.1
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• pp.42-50
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• 2011

One of the important applications of THz time-domain spectroscopy (TDS) is the detection of explosive materials through identification of vibrational fingerprint spectra. Most recent THz spectroscopic measurements have been made using pellet samples, where disorder effects contribute to line broadening, which results in the merging of individual resonances into relatively broad absorption features. To address this issue, we used the technique of parallel plate waveguide (PPWG) THz-TDS to achieve sensitive characterization of three explosive materials: TNT, RDX, and HMX. The measurement method for PPWG THz-TDS used well-established ultrafast optoelectronic techniques to generate and detect sub-picosecond THz pulses. All materials were characterized as powder layers in 112 ${\mu}m$ gaps in metal PPWG. To illustrate the PPWG THz-TDS method, we described our measurement by comparing the vibrational spectra of the materials, TNT, RDX, and HMX, applied as thin powder layers to a PPWG, or in conventional sample cell form, where all materials were placed in Teflon sample cells. The thin layer mass was estimated to be about 700 ${\mu}g$, whereas the mass in the sample cell was ~100 mg. In a laboratory environment, the absorption coefficient of an explosive material is essentially based on the mass of the material, which is given as: ${\alpha}({\omega})=[ln(I_R({\omega})/I_S({\omega}))]m$. In this paper, we show spectra of 3 different explosives from 0.2 to 2.4 THz measured using the PPWG THz-TDS.

• Journal of Soil and Groundwater Environment
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• v.14 no.1
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• pp.51-60
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• 2009

A series of experiments was performed to develop an optimized analytical procedure for the analysis of explosives in soil by HPLC with soil samples collected at two live-fire military shooting ranges. The minimum amount of soil to be collected, Wmin, for the analysis of explosive compounds was 125g, based on the segregation and homogeneity constants that account for soil heterogeneity and non-homogeneous distribution of target explosive compounds. The optimization of extraction and HPLC analytical conditions were also studied based on analytes CV values. The most effective soil/ extractant ratio was estimated to be 10g-pretreated soil/20 mL acetonitrile as extractant. The optimized HPLC elution conditions for the separation of US EPA designated 14 explosive compounds, were column temperature 30${\circ}C$, eluents ratio of isopropanol: acetonitrile: water = 18 : 12: 70, and flow rate of 0.8 mUmin at 230 nm. However, UV wavelength 254 nm was better for the analysis of NB, 2,4-DNT, 2NT, 4NT, and 3NT.

• Korean Journal of Computational Design and Engineering
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• v.18 no.3
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• pp.155-166
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• 2013

We present recent human-vehicle interaction (HVI) research conducted in the area of defense and military application. Research topics discussed in this paper include: training simulation for overland navigation tasks; expertise effects in overland navigation performance and scan patterns; pilot's perception and confidence on an overland navigation task; effects of UAV (Unmanned Aerial Vehicle) supervisory control on F-18 formation flight performance in a simulator environment; autonomy balancing in a manned-unmanned teaming (MUT) swarm attack, enabling visual detection of IED (Improvised Explosive Device) indicators through Perceptual Learning Assessment and Training; usability test on DaViTo (Data Visualization Tool); and modeling peripheral vision for moving target search and detection. Diverse and leading HVI study in the defense domain suggests future research direction in other HVI emerging areas such as automotive industry and aviation domain.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.11a
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• pp.349-349
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• 2005

• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.682-684
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• 2003

With the explosive rapid expansion of computer using during the past few years, security has become a crucial issue for modem computer systems. Today, there are many intrusion detection systems (IDS) on the Internet. A variety of intrusion detection techniques and tools exist in the computer security community such as enterprise security management system (ESM) and system integrity checking tools. However, there is a potential problem involved with intrusion detection systems that are installed locally on the machines to be monitored. If the system being monitored is compromised, it is quite likely that the intruder will after the system logs and the intrusion logs while the intrusion remains undetected. In this project KIT-I, we adopt remote logging server (RLS) mechanism, which is used to backup the log files to the server. Taking into account security, we make use of the function of SSL of Java and certificate authority (CA) based key management. Furthermore, Support Vector Machine (SVM) is applied in our project to detect the intrusion activities.

• Biomedical Science Letters
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• v.29 no.3
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• pp.109-120
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• 2023

Recently, the explosive increase of carbapenemase-producing Enterobacterales (CPE) in the worldwide poses a serious threat. The purpose of this study is to investigate epidemiology, detection, and treatment of CPE. Three main carbapenemase are reported worldwide, which were KPC, NDM, and OXA-48-like. KPC type are mostly found in USA, China, Europe, and Latin America. NDM type are mostly found in South Asia. OXA-48-like are often seen in the Mediterranean and Northern Africa. In Korea, CPE have increased explosively since 2015. In 2021, 18,099 CPE were isolated, which were Klebsiella pneumoniae, Escherichia coli, and Enterobacter cloacae in order. The CPE genotype was distributed with KPC, NDM, OXA type in order. Phenotypic detection methods include carbapenemase production tests (CPT) and differential tests of CPE. CPTs include modified Hodge test, modified carbapenem inactivation method (mCIM), Carba NP test, among which mCIM is the most widely used due to easy accessibility and accuracy. A lot of genotypic methods are being done for quick results, and commercialized kits using multiplex real-time PCR and microarray are widely used. Colistin and tigecycline are used as the first line of CPE treatment and are used in combination with second line drugs such as meropenem and fosfomycin.

• Journal of Sensor Science and Technology
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• v.31 no.4
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• pp.187-193
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• 2022

The accurate detection of environmental and biomarker gas species has attracted increasing attention due to their broad applications, such as air quality monitoring, disease diagnosis, and explosive chemicals detection. To accurately detect target gas species using chemiresistive gas sensors, using nanocatalysts on semiconducting metal oxides (SMOs) is considered the most promising approach. This review summarizes recent studies on methods for nanocatalysts functionalization on SMOs to achieve the highly selective gas sensors. To this end, we discuss various nanocatalyst decorated metal oxide-based chemiresistive gas sensors and provide an insight to construct highly accurate gas sensors.