• Journal of Life Science
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• v.33 no.8
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• pp.639-650
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• 2023

The levels of harmful components in aerosols from heated tobacco products (HTPs) have been reported to be significantly lower than in cigarette smoke. However, it remains unclear whether the use of HTPs can mitigate the cardiovascular risks associated with cigarette smoking (CS). The objective of this study was to investigate the effects of a short-term switch from CS to HTP use on cardiac autonomic regulation (CAR). Seven healthy male smokers completed an open-label, randomized, cross-over trial consisting of five days of CS, use of three different HTPs (IQOS use, IQ; lil SOLID use, LS; lil HYBRID use, LH), or non-smoking (NS). Each session was separated by a one-week washout period, and levels of exhaled carbon monoxide (CO) and carboxyhemoglobin (COHb), systolic (SBP) and diastolic blood pressure (DBP), and heart rate variability (HRV) reflecting CAR were assessed before use of the product assigned to each session and at 24, 48, 72, 96, and 120 hr after use. Levels of exhaled CO and COHb were statistically significantly reduced only during NS. There were no statistical changes in SBP and DBP within any session. However, in HRV spectral analysis, log-transformed high frequency (lnHF) increased statistically significantly in IQ, LS, and NS, respectively. Normalized HF (HFnu) was significantly increased in NS and LH, respectively. lnHF and HFnu showed significant interaction effects. The findings of this study suggest that a short-term switch to HTPs instead of CS may lead to different distribution patterns of CAR, primarily driven by enhanced cardiac vagal tone.

• Journal of Photoscience
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• v.7 no.4
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• pp.155-159
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• 2000

[Ru(bpy)$_2$(dppz)]$^2$$^{+}$ (bpy = 2,2'-bipyridine, dppz = dipyrido[3,2-a:2',3'-c]phenazine)(RuBD), a long-lifetime metal-ligand complex displays photophysical properties including long lifetime, polarized emission, and very little background fluorescence. To further show the usefulness of this luminophore(RuBD) for probing nucleic acid dynamics, its intensity and anisotropy decays when bound to tRN $A^{val}$ were examined using frequency-domain fluorometry with a blue light-emitting diode(LED)as the modulated light source. Unexpectedly much longer mean lifetime was obtained at 4$^{\circ}C$(<$\tau$>=178.3 ns) as compared to at $25^{\circ}C$(<$\tau$>=117.0 ns), suggesting more favorable conformation of tRN $A^{val}$ for RuBD when intercalated at 4$^{\circ}C$. The anisotropy decay data showed longer rotational correlation times at 4$^{\circ}C$(52.7 and 13.0 ns) than at $25^{\circ}C$ (32.9 and 10.3 ns). The presence of two rotational correlation times suggests that RuBD reveals both local and overall rotational motion of tRN $A^{val}$. Due to long lifetime of RuBD and small size of tRN $A^{val}$, very low steady-state anisotropy values were observed, 0.048 and 0.036 at 4 and $25^{\circ}C$, respectively. However, a clear difference in the modulated anisotropy values was seen between 4 and $25^{\circ}C$. These results indicate that RuBD can be useful for studying hydrodynamics of small nucleic acids such as tRN $A^{val}$.^{val}$.>.$.>.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.8B
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• pp.529-538
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• 2007

In this paper, we have analyzed a simulation model of Slammer worm propagation process which caused serious disruptions on the Internet in the year of 2003 by using NS-2. Previously we had presented and analyzed Abstract Network to Abstract Network(AN-AN) model being modified from the Detailed Network to Abstract Network(DN-AN) of NS-2. However, packet analysis in AN-AN model had a problem of taking 240 hours to simulate the initial 300 seconds of infection. We have reduced the AN-AN model to save the simulation time and analyzed total 3.5 hours of the network congestions within 107 hours. Moreover, we have derived optimal quarantine rate of 0.0022 considering service outage of network devices caused by the heavy infected traffics, which was not taken into consideration in previous works. As the result of simulation, Although the inbound traffic at the Korean international gateway was back in normal conditions at 4,787 second, due to the revese direction saturation was maintained until 12,600 seconds, the service outage was persisted for 3.5 hours.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.9 s.351
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• pp.64-68
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• 2006

Novel system-on-package (SOP) - D technology to improve the mechanical and thermal properties of a MCM-D substrate was suggested. Based on this investigation, the two types of band pass filters for the V-band application with unique structure were designed and implemented using 2-metals, 3-BCB layers. The first type using distributed resonator had the insertion loss below 2.6 dB at 55 GHz and group delay was below 0.06 ns. For the second type with edge coupled structure, the insertion loss and group delay were 3 dB and 0.1 ns, respectively. Suggested MCM-D substrate with band pass filter can be used to evaluate mm-Wave system including flip-chip bonded MMIC.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.12
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• pp.66-74
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• 2001

In this paper, we proposed the new structure of the Rake Finger using Walsh Switch, the shared accumulator, and the pipeline FWHT(Fast Walsh Hadamard Transform) algorithm for reducing the signal processing complexity resulting from the increase of the number of data correlators. The function simulation of the proposed architecture is performed by Synopsys tool and the timing simulation is performed by Compass tool. The number of computational operation in the proposed data correlators is 160 additions and the conventional ones is 512 additions when the number of walsh code channels is 4. As a result, it is reduced about 3.2 times other than the number of computational operation of the conventional ones. Also, the result shows that the data processing time of the proposed Rake Finger architecture is 90,496[ns] and the conventional ones is 110,696[ns]. It is 18.3% faster than the data processing time of the conventional Rake Finger architecture.

• Journal of IKEEE
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• v.17 no.3
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• pp.260-266
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• 2013

The open bit line is vulnerable to noise compared to the folded bit line when read/write for the DRAM. According to the increasing DRAM densities, the core circuit operating conditions is exacerbated by the noise when it comes to the open bit line 6F2(F : Feature Size) structure. In this paper, the interference effects were analyzed by the data patterns between the bit line by experiments. It was beyond the scope of existing research. 68nm Tech. 1Gb DDR2, Advan Tester used in the experiments. The noise effects appears the degrade of internal operation margin of DRAM. This paper investigates sense amplifier power line splits by experiments. The noise can be improved by 0.2ns(1.3%)~1.9ns(12.7%), when the sense amplifier power lines split. It was simulated by 68nm Technology 1Gb DDR2 modeling.

• Archives of Pharmacal Research
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• v.25 no.2
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• pp.143-150
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• 2002

Fluorescent probes bound to DNA typically display nanosecond decay times and reveal only nanosecond motions. We extend the time range of measurable DNA dynamics using $[Ru(pby)_2(dppz)]^{2+}$ (bpy=2.2'-bipyridine, dppz=dipyrido[3,2-a2',3'-c]phenazine) (RuBD) which displays a mean lifetime near 90 ns. To test the usefulness of RuBD as a probe for diffusive processes in calf thymus DNA, we compared the efficiencies of fluorescence resonance energy transfer (FRET) using three donors which display lifetimes near 5 ns for acridine orange (AO), 22 ns for ethidum bromide (EB) and 92 ns for RuBD, with nile blue (NB) as the acceptor. The F rster distances for AO-NB, EB-NB and RuBD-NB donor-acceptor pairs were 42.3, 52.3, and $30.6{\;}{\AA}$, respectively. All three donors showed dramatic decreases in fluorescence intensities and more rapid intensity decays with increasing NB concentrations. The intensity decays of AO and EB in the presence of varying concentrations of NB were satisfactorily described by the one-dimensional FRET model without diffusion (Blumen and Manz, 1979). In the case of the long-lifetime donor RuBD, the experimental phase and modulation somewhat deviated from the recovered values computed from this model. The recovered NB concentrations and FRET efficiencies from the model were slightly larger than the expected values, however, the recovered and expected values did not show a significant difference. Thus, it is suggested that the lifetime of RuBD is too short to measure diffusive processes in calf thymus DNA.

• Journal of KIISE:Information Networking
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• v.36 no.3
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• pp.184-190
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• 2009

WiBro has advantages when both WLAN and 3G UMTS are adopted. Much research is being carried out in this area. However, the WiBro specification does not consider end-to-end security. Hence, another security protocol has to be adopted to support secure communication. Most previous research only focused on WiBro MAC performance improvement or security. In this paper, we adopt a security protocol such as IPsec, TLS, and DTLS, well known end-to-end security protocols, to make full use of WiBro in the IP network. Using NS-2 we simulated the adoption of end-to-end security protocol and evaluated performance and usability. Simulation shows DTLS had some performance advantages. All the protocols, TLS and IPsec are also suitable for use in WiBro.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.2
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• pp.1211-1215
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• 2014

We developed a new $Rb_2LiCeCl_6$ scintillator and determined the scintillation and thermoluminescence properties of the scintillator. The emission spectrum of $Rb_2LiCeCl$ is located in the range of 350 ~ 410 nm, peaking at 368 nm and 378 nm, due to the 4f ${\rightarrow}$ 5d transition of $Ce^{3+}$ ions. The fluorescence decay time of the crystal is composed two components. The fast component is 71 ns (85%) and the slow component is 405 ns (15%) of the crystal. The after-glow is caused by the electron and hole traps in the crystal lattice. We determined physical parameters of the traps in the crystal. The determined activation energy(E), kinetic order(m) and frequency factor(s) of the trap are 0.75 eV, 1.48 and $3.0{\times}10^8s^{-1}$, respectively.

• Journal of Photoscience
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• v.11 no.3
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• pp.133-139
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• 2004

The metal-ligand complex, $[Ru(phen)_2(dppz)]^{2+}$ (phen=1,10-phenanthroline, dppz=dipyrido[3,2-a:2',3'-c]phenazine) (RuPD), was used as a spectroscopic probe for studying nucleic acid dynamics. The RuPD complex displays a long lifetime and a molecular light switch property upon DNA binding due to shielding of its dppz ligand from water. To show the usefulness of this luminophore (RuPD) for probing nucleic acid dynamics, we compared its intensity and anisotropy decays when intercalated into the $tRNA^{val}$ and pBluescript (pBS) II SK(+) phagemid through a comparison with ethidium bromide (EB), a conventional nucleic acid probe. We used frequency-domain fluorometry with a blue light-emitting diode (LED) as the modulated light source. The mean lifetime for the $tRNA^{val}$ (<${\tau}$> = 166.5 ns) was much shorter than that for the pBS II SK(+) phagemid (<${\tau}$> = 481.3 ns), suggesting a much more efficient shielding from water by the phagemid. Because of their size difference, the anisotropy decay data showed a much shorter rotational correlation times for the $tRNA^{val}$ (99.9 and 23.6 ns) than for the pBS II SK(+) phagemid (968.7 and 39.5 ns). These results indicate that RuPD can be useful for studying nucleic acid dynamics.