• The Korean Journal of Pain
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• v.7 no.1
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• pp.74-77
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• 1994

Since its introduction, low level lasers have been utilized in many varied clinical applications for the treatment of musculoskeletal and body surface lesions. Due to the laser beams specific characteristic-coherence, monochromaticity and unidirectionality, without adverse reaction with neighbouring tissue, physicians have used it with relative ease. We observed accelerating effects of healing process of some intractable skin wound, improvement of graft survival, as well as reduction of pain on ulcerating tissues, by treating twice weekly with low level Helium-Neon(He-Ne) and Infrared(IR) laser. The laser's energy density was set at $1\;J/cm^2$ and a fixed frequency of 600 Hz by continuous scanning. Irradiating time was calculated according to the cross diameter of the wound. Further clinical work will be required to evaluate the accelerated healing processes by biostimulating mechanisms of laser ray, especially for the intractable(diabetic) skin ulceration.

• Bulletin of the Korean Space Science Society
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• 2010.04a
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• pp.40.3-40.3
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• 2010

The most frequently suggested source for Pi2 pulsations in the inner magnetosphere (L < 4) is standing fast-mode waves trapped in the plasmasphere (i.e., plasmaspheric resonances). They have been considered as the source of low-latitude Pi2 pulsations. The plasmaspheric resonance model suggests that compressional fast-mode waves can be detected at all local times inside the plasmasphere provided reflection of the wave energy is efficient. Until now, however, there are no reports about compressional Pi2s observed in the dayside inner magnetosphere. That is, there is longitudinal limit of inner magnetosphere. In February 2008, THEMIS probes were near dawn and/or dusk sides, which are the transition regions between the nightside and dayside, in the inner magnetosphere (L = 2-4) when low-altitude Pi2s were identified at Bohyun (L = 1.35) station in Korea. Using the THEMIS electric field data, we examined if Pi2s are excited by longitudinally localized disturbances. We found that compressional Pi2s having high coherence with a low-latitude Pi2 pulsation occur on dawnside. However, any compressional pulsations in the Pi2 frequency band were not detected on duskside. This indicates that compressional Pi2s disappear near the duskside. Our observations are discussed with spatial plasmaspheric structure and possible Pi2 mechanisms.

• The KIPS Transactions:PartA
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• v.13A no.2 s.99
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• pp.101-110
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• 2006

One of the most effective ways to improve cache performance is to exploit both temporal and spatial locality given by any program executional characteristics. This paper proposes a data cache with small space for low power but high performance on multimedia applications. The basic architecture is a split-cache consisting of a direct-mapped cache with small block sire and a fully-associative buffer with large block size. To overcome the disadvantage of small cache space, two mechanisms are enhanced by considering operational behaviors of multimedia applications: an adaptive multi-block prefetching to initiate various fetch sizes and an efficient block filtering to remove rarely reused data. The simulations on MediaBench show that the proposed 5KB-cache can provide equivalent performance and reduce energy consumption up to 40% as compared with 16KB 4-way set associative cache.

• Advances in environmental research
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• v.10 no.1
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• pp.59-86
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• 2021

Landfilling is the most commonly adopted method for a large quantity of waste disposal. But, the main concern related to landfills is the generation of leachate. The leachate is high strength wastewater that is usually characterized by the presence of high molecular recalcitrant organics. Several conventional methods are adopted for leachate treatment. However, these methods are only suitable for young leachate, having high biodegradability and low toxicity levels. The mature and stabilized leachate needs advanced technologies for its effective treatment. Advanced oxidation processes (AOPs) are very suitable for such complex wastewater treatment as reported in the literature. After going through the literature survey, it can be concluded that Fenton-based approaches are effective for the treatment of various high/low strength wastewaters treatment. The applications of the Fenton-based approaches are widely adopted and well recognized due to their simplicity, cost-effectiveness, and reliability for the reduction of high chemical oxygen demand (COD) as reported in several studies. Besides, the process is relatively economical due to fewer chemical, non-sophisticated instruments, and low energy requirements. In this review, the conventional and advanced Fenton's approaches are explained with their detailed reaction mechanisms and applications for landfill leachate treatment. The effect of influencing factors like pH, the dosage of chemicals, nature of reaction matrix, and reagent ratio on the treatment efficiencies are also emphasized. Furthermore, the discussion regarding the reduction of chemical oxygen demand (COD) and color, increase in biodegradability, removal of humic acids from leachate, combined processes, and the pre/post-treatment options are highlighted. The scope of future studies is summarized to attain sustainable solutions for restrictions associated with these methods for effective leachate treatment.

• Computers and Concrete
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• v.21 no.3
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• pp.335-344
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• 2018

More and more special-shaped structural systems have been widely used in various industrial and civil buildings in order to satisfy the new structural system and the increasing demand for architectural beauty. With the popularity of the special-shaped structure system, its seismic performance and damage form have also attracted extensive attention. In the current research, an experimental analysis of six groups of (2/3 scale) T-shaped column joints was conducted to investigate the seismic performance of T-shaped column joints. Effects of the beam cross section, transverse stirrup ratio and axial compression ratio on bearing capacity and energy dissipation capacity of column joints were obtained. The crack pattern of T-shaped column joints under low cyclic load was presented and showed a reversed "K" mode. According to the crack configurations, a tensile-shear failure model to determine the shear bearing capacity and crack propagation mechanisms is developed.

• 한국지구물리탐사학회:학술대회논문집
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• 2004.06a
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• pp.232-237
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• 2004

Anatahan Volcano in the Commonwealth of the Northern Mariana Islands (CNMI) erupted for the first time in recorded history on 10 May 2003. The underwater acoustic records of earthquakes, explosions, and tremor produced during the eruption were recorded on a sound-channel hydrophone deployed in February 2003. Acoustic propagation models show the seismic to acoustic conversion at Anatahan is particularly efficient, aided by the slope of the seamount toward the hydrophone. The hydrophone records confirm the onset of earthquake activity at 01:53Z on 10 May, as well as the onset (at ${\~}$06:20Z) of continuous, low-frequency (5-40 Hz) acoustic energy that is likely volcanic tremor related to magma intrusion. The hydrophone recorded a total of 458 earthquakes associated with the eruption. To predict the character of acoustic signals generated from Anatahan, we developed a moment-tensor representation of a volcano-seismic source that is governed by the geometry of the source and the physical properties of the magma. A buried magmatic pipe model was adopted, and numerically modeling source parameters such as the pipe radius and magma viscosity enable us to grasp the inward nature of Anatahan Volcano.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.3
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• pp.220-226
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• 2002

Amorphous $Sb_{2-x}Bi_xTe_3$ (x = 0.0, 0.5 and 1.0) thin films were prepared by vacuum evaporation. The resistivity of 7he films decreases from 1.4{\times}10^{-2}$ to $8.84{\times}10^{-5}\Omega cm$ and the type of conductivity changes from p to n with the increase of the x value of the films. D.C. conduction studies on these films ate performed at various electric fields in the temperature range of 303-403 K. At low electric fields, two types of conduction mechanisms, i.e. the variable range hopping and the phonon assisted hopping are found to be responsible for the conduction, depending upon the temperature. The activation energy decreases from 0.082 to 0.076 eV in the temperature range of 303-363 K and from 0.47-0.456 eV in the second range of 363-403 K, indicating the shift of the Fermi level towards the conduction band edge and hence the change of the conduction from P to n type with the increase of the Bi concentration. Poole-Frankel emission dominates at high fields. The shape of the potential well of the localized centre is deduced and the mean free path of the charge carriers is also calculated.

• IEMEK Journal of Embedded Systems and Applications
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• v.12 no.3
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• pp.131-138
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• 2017

QR/NFC tags have been utilized in various fields like exhibition, museum, and so on, but they have a drawback that they are read-only fundamentally. We devise a novel device called a smart memory tag (below mem-tag) which is supplemented with the write function through combining a flash memory into a NFC tag. A mem-tag is composed of an NFC tag, an MCU, a flash memory, a bluetooth module, and a battery, and is inter-operating with smartphones via bluetooth communication. It can be used in a bulletin board to support writing replies and in a check-in service to verify the presence of the site. What matters is that users' inter-operations are borne to be asynchronous, which leads to the energy consumption to wait for users' actions. Sleep mechanisms and asynchronous MAC protocols used in ubiquotous sensor networks cannot avoid the consumption of battery. In this paper, we propose a touch and play scheme for minimizing the consumption of battery that the MCU wakes up and PLAY when a user TOUCH the mem-tag. We implemented the system to show that our scheme lets the mem-tag work 50 times longer than the sleep and wake-up scheme.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.90.1-90.1
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• 2012

Understanding the dynamics of relativistic electron acceleration, loss, and transport in the Earth's radiation belt during magnetic storms is a challenging task. The U.S. National Science Foundation's Geospace Environment Modeling (GEM) has identified five magnetic storms for in-depth study that occurred during the second half of the Combined Release and Radiation Effects Satellite (CRRES) mission in the year 1991. In this study, we show the responses of relativistic radiation belt electrons to the magnetic storms by comparing the time-dependent 3-D Versatile Electron Radiation Belt (VERB) simulations with the CRRES MEA 1 MeV electron observations in order to investigate the relative roles of the competing effects of previously proposed scattering mechanisms at different storm phases, as well as to examine the extent to which the simulations can reproduce observations. The major scattering processes in our model are radial transport due to Ultra Low Frequency (ULF) electromagnetic fluctuations, pitch-angle and energy diffusion including mixed diffusion by whistler mode chorus waves outside the plasmasphere, and pitch-angle scattering by plasmaspheric hiss inside the plasmasphere. We provide a detailed description of simulations for each of the GEM storm events.

• Membrane and Water Treatment
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• v.8 no.1
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• pp.89-112
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• 2017

Dyeing wastewaters are the most problematic wastewater in textile industries and also, growing amounts of waste fibers in carpet industries have concerned environmental specialists. Among different treatment methods, membrane filtration processes as energy-efficient and compatible way, were utilized for several individual problems. In this research, novel hybrid membranes were prepared by waste fibers of mechanical carpets as useful resource of membrane matrix and industrial graphite powder as filler to eliminate Chrysophenine GX from dyeing wastewater. These membranes were expected to be utilized for first stage of hybrid membrane filtration process including (adsorption-ultrafiltration) and nanofiltration in Kashan Textile Company. For scaling of membrane filtration process, fouling mechanism of these membranes were recognized and explained by the use of genetic algorithm, as well. The graphite increased rejection and diminished permeate flux at low concentration but in high concentration, the performance was significantly worsened. Among all hybrid membranes, 18% wt. waste fibers-1% wt. graphite membrane had the best performance and minimum fouling. The maximum pore size of this optimum membrane was ranged from 16.10 to 18.72 nm.