• Mass Spectrometry Letters
• /
• v.13 no.2
• /
• pp.27-34
• /
• 2022

Atmospheric aerosols have become a major environmental concern because of their adverse effects on human health, air quality, and climate change. Over the last few decades, several mass spectrometry (MS)-based techniques have been developed and applied in the field of atmospheric aerosol research. Particularly, real-time measurement of ambient aerosols using an aerosol mass spectrometer (AMS) has become one of the most powerful tools for aerosol chemistry. This review provides a brief description of AMS and its applications for understanding the physicochemical properties of atmospheric aerosols, as well as its sources and evolution processes.

• Journal of the Korean earth science society
• /
• v.22 no.2
• /
• pp.89-95
• /
• 2001

The purposes of the study are (1) to develop a Computer-Assisted Instruction (CAI) program to deal with middle school students' misconceptions on the concept of atmospheric pressure, and (2) to investigate the effects of the CAI on students' achievement and conceptual change. The findings of the study are as follows: (1) Misconceptions about atmospheric pressure found are similar to the ones identified in earlier studies, (2) A CAI program on atmospheric pressure was developed based on the students' misconceptions identified, and (3) The instruction using CAI program has very positive effects on students' science achievement and conceptual change.

• Biomolecules & Therapeutics
• /
• v.22 no.6
• /
• pp.477-490
• /
• 2014

Non-thermal atmospheric-pressure plasma, also named cold plasma, is defined as a partly ionized gas. Therefore, it cannot be equated with plasma from blood; it is not biological in nature. Non-thermal atmospheric-pressure plasma is a new innovative approach in medicine not only for the treatment of wounds, but with a wide-range of other applications, as e.g. topical treatment of other skin diseases with microbial involvement or treatment of cancer diseases. This review emphasizes plasma effects on wound healing. Non-thermal atmospheric-pressure plasma can support wound healing by its antiseptic effects, by stimulation of proliferation and migration of wound relating skin cells, by activation or inhibition of integrin receptors on the cell surface or by its pro-angiogenic effect. We summarize the effects of plasma on eukaryotic cells, especially on keratinocytes in terms of viability, proliferation, DNA, adhesion molecules and angiogenesis together with the role of reactive oxygen species and other components of plasma. The outcome of first clinical trials regarding wound healing is pointed out.

• Proceedings of the Korea Air Pollution Research Association Conference
• /
• 2004.11a
• /
• pp.35-40
• /
• 2004

Atmospheric aerosols have a key role in both local and global environmental problems. The physicochemical properties of aerosols and their spatial distribution are essential to understand their effects on the environment and health.

• Journal of IKEEE
• /
• v.1 no.1 s.1
• /
• pp.47-54
• /
• 1997

Today's communication needs the super high-speed data transmission system to send many data rapidly, correctly, and simultaneously because of the increase of internet use, the demand of multimedia service and so on. Before long, the super high data service will be offered us by a satellite called platform which will be located at stratosphere of 20[km]over earth. It is possible to build the optical wireless communication networks which have the high data-tarrying capacity because this system use a laser. But, there are many problems to overcome because it make use of the atmospheric space as transmission channel. In this paper, therefore, we study up on the relations of data rates, bit error rates, and turbulent effects of atmosphere to present the effects of atmosphere to present the effects of atmospheric turbulence on the optical satcom link.

• Journal of IKEEE
• /
• v.2 no.2 s.3
• /
• pp.194-199
• /
• 1998

In the atmospheric wireless optical communication system, the low power transmission can be accomplished by the high directivity of laser beam. But, the transmitted optical signal undergoes the serious influences by the atmospheric effects like absorption, scattering, and turbulence because the transmission channel is the atmospheric space. In this paper, therefore, we obtain the link equation for an atmospheric wireless optical LOS communication link under the atmospheric effects and find the repeaterless transmission length to estimate the system performance through the computer simulation. From the results of the computer simulation, we present the transmission length that is possible to transmit without a repeater at given data rates and know that data rate is decreased rapidly when the transmission length is increased slightly at given bit error rate.

• Proceedings of the Korea Air Pollution Research Association Conference
• /
• 2003.11a
• /
• pp.51-52
• /
• 2003

A numerical study on PM using a dispersion and deposition model which can analyze for both quantify and quality would not only offer us to understand our environment more easily, but also make it easy that we can make a plan in order to prevent air pollution. The U.S. EPA has proposed the CALPUFF modeling system as a guideline model for regulatory applications involving long-range transport and on a case-by-case basis for near-field applications where. non- steady- state effects which consider situations such as spatial variability in the meteorological fields, calm winds, fumigations, re-circulation or stagnation, and terrain or coastal effects may be important. (omitted)

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.25 no.11
• /
• pp.123-129
• /
• 2011

In terrestrial wireless optical communication links, atmospheric effects including turbulence, absorption and scattering have significant impact on the system performance. Based on the analysis of transmission in atmospheric channel concerning 830[nm] wavelength diode laser beam, performance of free space optical (FSO) link utilizing Galilean optics as a laser beam transmitting and receving optics, PIN photodiode as a detecting device. In this paper we designed optical link equation for received optical power and we analyze the atmospheric effects on the signal to noise ratio (SNR) and bit error rate (BER) of an terrestrial FSO system. We show that the possible communication distance for BER=$10^{-9}$ in proposed adverse atmospheric conditions.

• Korean Journal of Remote Sensing
• /
• v.12 no.1
• /
• pp.81-88
• /
• 1996

The effects of atmospheric refraction of rays on the geometry of high-resolution images such as the KOMPSAT-EOC images are described. An atmospheric refraction mechanism is modelled and the geometric errors caused by the refraction are calculated from the model simulation. This paper shows that a maximum geometric error of 1 pixel (7m) occurs from the standard atmospheric condition. Severer geometric distortions in images cause from an atmopheric abnormality.

• Asian Journal of Atmospheric Environment
• /
• v.4 no.3
• /
• pp.115-140
• /
• 2010

Great concerns about atmospheric aerosols are attributed to their multiple roles to atmospheric processes. For example, atmospheric aerosols influence global climate, directly by scattering or absorbing solar radiations and indirectly by serving as cloud condensation nuclei. They also have a significant impact on human health and visibility. Many of these effects depend on the size and composition of atmospheric aerosols, and thus detailed information on the physicochemical properties and the distribution of airborne particles is critical to accurately predict their impact on the Earth's climate as well as human health. A single particle analysis technique, named low-Z particle electron probe X-ray microanalysis (low-Z particle EPMA) that can determine the concentration of low-Z elements such as carbon, nitrogen and oxygen in a microscopic volume has been developed. The capability of quantitative analysis of low-Z elements in individual particle allows the characterization of especially important atmospheric particles such as sulfates, nitrates, ammonium, and carbonaceous particles. Furthermore, the diversity and the complicated heterogeneity of atmospheric particles in chemical compositions can be investigated in detail. In this review, the development and methodology of low-Z particle EPMA for the analysis of atmospheric aerosols are introduced. Also, its typical applications for the characterization of various atmospheric particles, i.e., on the chemical compositions, morphologies, the size segregated distributions, and the origins of Asian dust, urban aerosols, indoor aerosols in underground subway station, and Arctic aerosols, are illustrated.