• Journal of Sensor Science and Technology
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• v.8 no.4
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• pp.314-319
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• 1999

The measurement of solid particles suspended in air is conducted with a quartz crystal microbalance. The measurement system is connected to a personal computer and multiple sensors are utilized to make simultaneous measurement possible. In this paper, the detail of experimental setup is extensively explained for the possible future application of the system in other areas. It is found that the measurement system is suitable for an on-line continuous determination of the concentration of solid particles in air.

• Journal of Sensor Science and Technology
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• v.17 no.6
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• pp.414-417
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• 2008

This paper describes the fabrication of a Pd/poly 3C-SiC Schottky diode and its characteristics, in which the poly 3C-SiC layer and Pd Schottky contact were deposited by using APCVD and sputter, respectively. Crystalline quality, uniformity, and preferred orientations of the Pd thin film were evaluated by SEM and XRD, respectively. Pd/poly 3C-SiC schottky diodes were fabricated and characterized by I-V and C-V measurements. Its electric current density Js and barrier height voltage were measured as $2{\times}10^{-3}A/cm^2$ and 0.58 eV, respectively. These devices were operated until about $400^{\circ}C$. Therefore, from these results, Pd/poly 3C-SiC Schottky devices have very high potential for high temperature chemical sensor applications.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.87-87
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• 2013

The interface between nanomaterials and biosystems is emerging as one of the broadest and most dynamic areas of science and technology, bringing together biology, chemistry, physics and many areas of engineering, biomedicine. The combination of these diverse areas of research promised to yield revolutionary advances in healthcare, medicine, and life science. For example, the creation of new and powerful nanosensors that enable direct, sensitive, and rapid analysis of biological and chemical species can advance the diagnosis and treatment of disease, discovery and screening of new drug molecules. Nanowire based sensors are emerging as a powerful and general platform for ultrasensitive and multiplex detection of biological and chemical species. Here, we present the studies about noble metal nanowire sensors that can be used for sensitive detection of a wide-range of biological and chemical species including nucleic acids, proteins, and toxic metal ions. Moreover, the optical and electrochemical applications of noble metal nanowires are introduced. Noble metal nanowires are successfully used as plasmonic antennas and nanoelectrodes, thereby provide a pathway for a single molecule sensor, in vivo neural recording, and molecular injection and detection in a single living cell.

• Applied Chemistry for Engineering
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• v.33 no.1
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• pp.1-10
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• 2022

This paper reviews the principles, advantages, and disadvantages of main explosives detection technologies, as well as research areas needed in the future. Explosives detection technology can be classified into spectroscopic methods, sensor techniques, and olfactory type sensors. There have been advances in explosives detection technology, however studies on discriminatory, portability, and sensitivity for explosives detection still remained competitive.

• Journal of Sensor Science and Technology
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• v.33 no.5
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• pp.310-317
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• 2024

Formaldehyde (HCHO) is a major primary indoor air pollutant with various adverse effects on the human body, includingsuch as sick building syndrome, lung cancer, and nasal cancer. Therefore, gas sensors for effective HCHO detection detecting HCHO are crucial for maintaining a healthy indoor environments, and research is being conducted to develop high-performance sensors for this purpose. AnOne of the effective methods for enhancing the to enhance sensing properties is involves modifying the p-n heterojunction structure, which improves sensing through via electronic sensitization based on the expanded depletion region and chemical sensitization that dissociates specific gases. In this studyHerein, weWe fabricated NiO-decorated In₂O₃ NRs using an e-beam evaporator based on the glancing angle deposition technique by optimizing the NiO thickness (0, 1, 2, and 3 nm). When exposed to 50 ppm HCHO, NiO-decorated In₂O₃ NRs showed a 3.91%-fold enhancement in the gas response (Ra/Rg-1= 23.9) and a 41.47% faster response time (40.7 s) than-compared to bare In₂O₃ NRs with an extremely low theoretical detection limit of ≈approximately 9.3 ppb.

• Journal of Sensor Science and Technology
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• v.16 no.2
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• pp.97-103
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• 2007

Crystallized carbon nitride film that has many stable physical and/or chemical properties has been expected potentially by a new electrical material. However, one of the most significant problems degrading the quality of carbon nitride films is an existence of N-H and C-H bonds from the deposition environment. The possibility of these reactions with hydroxyl group in carbon nitride films, caused by a hydrogen attack, was suggested and proved in our previous reports that this undesired effect could be applied for fabricating micro-humidity sensors. In this study, MIS capacitor and MIM capacitor with $5{\mu}m{\times}5{\mu}m$ meshes were fabricated. As an insulator, carbon nitride film was deposited on a $Si_{3}N_{4}/SiO_{2}/Si$ substrate using reactive magnetron sputtering system, and its dielectric constant, C-V characteristics and humidity sensing properties were investigated. The fabricated humidity sensors showed a linearity in the humidity range of 0 %RH to 80 %RH. These results reveal that MIS and MIM $CN_{X}$ capacitive humidity sensors can be used for Si based micro-humidity sensors.

• Korean Journal of Hazardous Materials
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• v.3 no.1
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• pp.28-36
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• 2015

In early 2011, the Fukushima nuclear power plant had greater damage due to earthquake in Japan, and the awareness of safety has increased. In particular, special response systems should be required to handle disaster situations in plant sites which are likely to occur for large disasters. In this study, a program is designed to set up optimum escape routes, by a smart phone application, when a disaster situation occurs. This program could get information of the cumulative damage from sensors and display the escape route of the smallest damage in real-time on the screen. Utilizing our application in real-time evacuation has advantage in reducing cumulative damage. The optimal evacuation route, focusing on horizontal path, is calculated based on getting the data of fire, detected radioactivity and hazardous gas. Thus, using our application provides information of optimal evacuation to people who even can not hear sensor alarms or do not know geography, without requiring additional costs except fixed sensors or server network deployment cost. As a result, being informed of real-time escape route, the user could behave rapidly with suitable response to individual situation resulting in improved evacuation than simply reacting to existing warning alarms.

• Bulletin of the Korean Chemical Society
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• v.31 no.3
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• pp.712-715
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• 2010

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.93-94
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• 2005

• Polymer Science and Technology
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• v.18 no.4
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• pp.306-310
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• 2007