• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.10
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• pp.4002-4014
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• 2015

ITU-R M.1842-1, as a well-known specification dedicated to maritime mobile applications, has standardized wireless transmission protocols according to the particular characteristics of a maritime communications scenario. A time division multiple access (TDMA) frame structure, along with modulation schemes to achieve a high data rate, has been described clearly in ITU-R M.1842-1. However, several specification items are still under "to be decided" status, which brings ambiguity to research works. In addition, the current version of ITU-R M.1842-1 is focused mainly on maritime transmissions in open-sea areas, where the cyclic prefix (CP) is set to zero and only 16-QAM is used in the multi-carrier (MC) system. System performance might be dramatically degraded in coastline areas due to the inter-symbol interference (ISI) caused by selective fading. This is because there is a higher probability that the signal will be reflected by obstacles in coastline areas. In this paper, we introduce the transmission resource block (TRB) dedicated to ITU-R M.1842-1 for a ship ad-hoc network (SANET), where the pilot pattern of TRB is based on the terrestrial trunked radio (TETRA). After that, we evaluated SANET performance under the maritime channel model in a coastline area. In order to avoid noise amplification and to overcome the ISI caused by selective fading, several strategies are suggested and compared in the channel estimation and equalization procedures, where the link-level simulation results finally validate our proposals.

• Journal of Oriental Neuropsychiatry
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• v.24 no.4
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• pp.363-372
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• 2013

Objectives: The purpose of this study is to investigate the usefulness of psychological measurements in depression symptoms as compared with non-depressions and hwabyung. Methods: A total of 21 patients, who were diagnosed with depression and hwabyung, were evaluated by using the SCL-90-R, BDI, STAI, STAXI, ISI, HRSD, 20-Item Alexithymia Scale, BSDS and NEO-PI. Thereafter, they were statistically analyzed. Results: 1) In the results of SCL-90-R, the PST score group of hwa-byung group without depression was significantly higher when compared to the score from the depression group without hwa-byung. 2) In the results of NEO-PI, the NEO-PI-O score of hwa-byung group without depression was significantly higher when compared to the score from the depression group without hwa-byung. 3) In the results of 20-Item Alexithymia Scale, the total score and score of difficulty for identifying feelings scale from the depression group was significantly higher when compared to the score of non depression group. Conclusions: The results found are expected to serve as a useful resource for future studies when developing the instruments of oriental medical evaluations for hwa-byung.

• Proceedings of the IEEK Conference
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• 2001.06d
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• pp.261-264
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• 2001

In this paper, we introduce a simple design method f9r mot-squared type raised cosine filter with equiripple characteristics. Through some design examples, we show that the proposed filter has much better performance in ripple than the conventional SRCF at the expense of small increasing of ISI. In addition, the proposed Inter is compatible with conventional SRCF. Finally, we designs the filter for W-CDMPI which uses RRC (Root Raised Cosine) with a=0.22, in 12bit finite precision.

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.4
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• pp.349-362
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• 2020

Temperature affects the firing pattern and electrical activity of neurons in animals, eliciting diverse responses depending on neuronal cell type. However, the mechanisms underlying such diverse responses are not well understood. In the present study, we performed in vitro recording of abdominal ganglia cells of Aplysia juliana, and analyzed their burst firing patterns. We identified atypical bursting patterns dependent on temperature that were totally different from classical bursting patterns observed in R15 neurons of A. juliana. We classified these abnormal bursting patterns into type 1 and type 2; type 1 abnormal single bursts are composed of two kinds of spikes with a long interspike interval (ISI) followed by short ISI regular firing, while type 2 abnormal single bursts are composed of complex multiplets. To investigate the mechanism underlying the temperature dependence of abnormal bursting, we employed simulations using a modified Plant model and determined that the temperature dependence of type 2 abnormal bursting is related to temperature-dependent scaling factors and activation or inactivation of potassium or sodium channels.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.4 no.1
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• pp.7-13
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• 2005

In this paper, we propose the time synchronization module on fiber optic repeater to use optic line delay for obtaining time synchronization between up-link and down-link, in the 2.3 GHz WiBro network using TDD/OFDM (Time Division Duplex/Orthogonal Frequency Division Multiplexing) Generally, when we use fiber optic repeater to remove the shade area, it occurs transmission delay which is caused by optic transmission between RAS (Radio Access Station) and fiber optic repeater and inner delay of fiber optic repeater. Because the WiBro system is adopting a TOO method and there exists the difference of switching time which is caused by these delay between up-link and down-link, it occurs ISI (Inter Symbol Interference), ICI (Inter Carrier Interference). These interference results in the reduction of the coverage. And the inconsistency between Up-Link and Down-Link switching time maybe gives rise to the interruption of communication. In order to prevent these cases, we propose synchronization module using analog optic line delay as the one of synchronizing up-link and down-link. And we propose the consideration factor for the designing time synchronization module and the feature of optic line of analog method. The measurement result of optic line time synchronization module of structure proposed is as follows, the delay error of $0.5{\mu}g$ and the insertion loss value below maximum 4.5dB in range of $0{\sim}40{\mu}s$. These results fully meet the specification of WiBro System.

• Korean Journal of Optics and Photonics
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• v.11 no.5
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• pp.323-329
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• 2000

In this study we have calculated an ideal complex refractive index of a TiN trim used in a layer of anl1reilecnon (I\R) coatmg, [air$ISiO_2ITiNIglass$] in the visible. Also we simulated the rellectance of lwo-layer AR coating by varying the thicknesses of TiN and $SiO_2$ layers, respecl1vely. The simolation results show that we can controllhe lowest reflectance and AR band of tile AR coating. The TIN fihns were fabricated by a RF magnetron sputtering apparalus. The chemical, structural and electrical properties of TiN fih11S were inveshgated by the Rutherford backscattering spech'oscopy (RBS), atomic force microscope (AFM) and 4-point probe. The optical properlies were inve,tigated by the spectrophotometer and vanable angle spectroscopic ellipsometer (VASE). The smface roughness of TiN flhns \vas $9~10\AA$. TIle resistivity of TiN films was TEX>$360~730\mu$\Omega $ cm. The ,toichlOllletry of TiN film was 1'1: O:N = I: 0.65 :0.95 and ilic oxygen wa~ found on ilie smface. With these experimental and simu]al1on resulLs, we deposited duo: two-layer AR coating, [air$ISiO_2ITiNIglass$] and the refleClance was under 0.5% ill the regIOn of 440-650 run. 0 run.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1510-1510
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• 2001

NIRS uses reflectance signals resulting from bending and stretching vibrations in chemical bonds between carbon, nitrogen, hydrogen, sulfur and oxygen. These reflectance signals are used to measure the concentration of major chemical composition and other descriptors of homogenized and freeze-dried whole broiler carcasses. Six strains of chicken were analyzed and the NIRS model predictions compared to reference data. The results of this comparison indicate that NIRS is a rapid tool for predicting dry matter (DM), fat, crude protein (CP) and ash content in the broiler carcass. Males and females of six commercial strain crosses of broiler chicken (Gallus domesticus) were used in this study (6$\times$2 factorial design). Each strain was grown to 16 weeks of age, and duplicate serial samples were taken for body composition analysis. Each whole carcass was pressure-cooked, homogenized, and a representative sample was freeze-dried. Body composition determined as follows: DM by oven dried method at 105$^{\circ}C$ for 3 hours, fat by Mojonnier diethyl ether extraction, CP by measuring nitrogen content using an auto-analyzer with Kjeldhal digest and ash by combustion in a muffle furnace for 24 hour at 55$0^{\circ}C$. These homogenized and freeze-dried carcass samples were then scanned with a Foss NIR Systems 6500 visible-NIR spectrophotometer (400-2500nm) (Foss NIR Systems, Silver Spring, MD., US) using Infra-Soft-International, ISI, WinISl software (ISI, Port Matilda, US). The NIRS spectra were analyzed using principal component (PC) analysis. This data was corrected for scatter using standard normal “Variate” and “Detrend” technique. The accuracy of the NIRS calibration equations developed using Partial Least Squares (PLS) for predicting major chemical composition and carcass descriptors- such as body mass (BM), bird dry matter and moisture content was tested using cross validation. Discrimination analysis was also used for sex and strain identification. According to Dr John Shenk, the creator of the ISI software, the calibration equations with the correlation coefficient, $R^2$, between reference data and NIRS predicted results of above 0.90 is excellent and between 0.70 to 0.89 is a good quantifying guideline. The excellent calibration equations for DM ($R^2$= 0.99), fat (0.98) and CP (0.92) and a good quantifying guideline equation for ash (0.80) were developed in this study. The results of cross validation statistics for carcass descriptors, body composition using reference methods, inter-correlation between carcass descriptors and NIRS calibration, and the results of discrimination analysis for sex and strain identification will also be presented in the poster. The NIRS predicted daily gain and calculated daily gain from this experiment, and true daily gain (using data from another experiment with closely related broiler chicken from each of the six strains) will also be discussed in the paper.

• The korean journal of orthodontics
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• v.20 no.1
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• pp.103-110
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• 1990

Metal brackets were recycled by variable methods for economic reason. Such recycling methods had a great effect on bracket slot width and bonding strength. Therefore, the recycling methods that don't change the properties of original bracket were suggested. In this study, debonded brackets were recycled with 30 kinds of solvents and bracket surfaces were examined by S.E.M. (Super IIIA, ISI International Scientific Instruments, Japan) and Stero Microscope (Sz-Tr, Olympus Tokyo, Japan) methods. The following results were obtained. 1. Thermosetting resin adhesives (eq. $Monolok^{(R)}$, $Concise^{(R)}$) were swelled most in sulfuric acid (assays 95%) and slightly in alcohol groups. 2. The solvent was exchanged every 24 hours during the brackets were recycled with sulfuric acid (assays 95%). As the passage of time, the adhesives were removed more clearly, and after 72 hours adhesives were nearly detached from bracket base. 3. Chemical recycled metal bracket surface showed no irregular structure by S.E.M. method.

• Nuclear Engineering and Technology
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• v.39 no.3
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• pp.171-186
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• 2007

Critical issues in the development targets for the future fast reactor(FR) cycle system, including sodium-cooled FR were to ensure safety assurance, efficient utilization of resources, reduction of environmental burden, assurance of nuclear non-proliferation, and economic competitiveness. A promising design concept of sodium-cooled fast reactor JSFR is proposed aiming at fully satisfaction of the development targets for the next generation nuclear energy system. A roadmap toward JSFR commercialization is described, to be followed up in a new framework of the Fast reactor Cycle Technology development(FaCT) Project launched in 2006.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1154-1154
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• 2001

Near infra-red (NIR) spectroscopy has been used for the non-invasive assessment of intact fruit for eating quality attributes such as total soluble solids (TSS) content. However, little information is available in the literature with respect to the robustness of such calibration models validated against independent populations (however, see Peiris et al. 1998 and Guthrie et al. 1998). Many studies report ‘prediction’ statistics in which the calibration and prediction sets are subsets of the same population (e. g. a three year calibration validated against a set from the same population, Peiris et al. 1998; calibration and validation subsets of the same initial population, Guthrie and Walsh 1997 and McGlone and Kawano 1998). In this study, a calibration was developed across 84 melon fruit (R$^2$= 0.86$^{\circ}$Brix, SECV = 0.38$^{\circ}$Brix), which predicted well on fruit excluded from the calibration set but taken from the same population (n = 24, SEP = 0.38$^{\circ}$Brix with 0.1$^{\circ}$Brix bias), relative to an independent group (same variety and farm but different harvest date) (n = 24, SEP= 0.66$^{\circ}$ Brix with 0.1$^{\circ}$Brix bias). Prediction on a different variety, different growing district and time was worse (n = 24, SEP = 1.2$^{\circ}$Brix with 0.9$^{\circ}$Brix bias). Using an ‘in-line’ unit based on a silicon diode array spectrometer, as described in Walsh et al. (2000), we collected spectra from fruit populations covering different varieties, growing districts and time. The calibration procedure was optimized in terms of spectral window, derivative function and scatter correction. Performance of a calibration across new populations of fruit (different varieties, growing districts and harvest date) is reported. Various calibration sample selection techniques (primarily based on Mahalanobis distances), were trialled to structure the calibration population to improve robustness of prediction on independent sets. Optimization of calibration population structure (using the ISI protocols of neighbourhood and global distances) resulted in the elimination of over 50% of the initial data set. The use of the ISI Local Calibration routine was also investigated.