• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.1
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• pp.100-107
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• 2007

AABR(automated auditory brainstem response) test is used for the screening purpose of hearing ability of neonates. In this paper, algorithm using Rolle's theorem is suggested for automatic detection of the ensemble averaged ABR waveform. The ABR waveforms were recorded from 55 normal-hearing ears of neonates at screening levels varying from 30 to 60 dBnHL. Recorded signals were analyzed by expert audiologist and by the proposed algorithm. The results showed that the proposed algorithm correctly identified latencies of the major ABR waves (III, V) with latent difference below 0.2 ms. No significant differences were found between the two methods. We also analyzed the ABR signals using derivative algorithm and compared the results with proposed algorithm. The number of detected candidate waves using the proposed algorithm was 47 % less than that of the existing one. The proposed method had lower relative errors (0.01 % error at 60dBnHL) compared to the existing one. By using proposed algorithm, clinicians can detect and label waves III and V more objectively and quantitatively than the manual detection method.

• Journal of Mushroom
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• v.16 no.3
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• pp.198-202
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• 2018

'Yong-A' was bred by Jeollanamdo Agricultural Research and Extension Services in 2015. It was primarily selected through monospore crossing between JNM21008 and JNM21013 in 2009. The strain is named as JNM-Mi-194 and 'Yong-A', showing major characteristics with good production yield. The cultivation characteristics, yield potential, and fruiting body characteristics of 'Yong-A' are as follows; The wrinkle of the fruiting body was of branching type its shape was wave type. MCM, YM, Malt, and PDA media were suitable for growth of this cultivar. The number of effective stipes was 13 ea/0.9 kg. The minor axis of pileus was 5 cm and the major axis was 9 cm. The yield was 291 g per plastic bag (0.9 kg). Yong-A required 60 days for mycelial running at $20^{\circ}C$. The growth and primordial period required 24 days, which was shorter than that of JNM-Mi-21002 (the conventional cultivar). Somatic incompatibility was observed between parental lines and Yong-A. Analysis of genetic diversity in the new variety 'Yong-A' showed a different profile compared to that of the parent strain when Random Amplified Polymorphic DNA primers were used.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.4
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• pp.567-576
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• 2017

In a performance-based design, the structural safety is estimated from pre- defined damage states and corresponding damage indices. Both damage states and damage indices are well defined for above-ground structures, but very limited studies have been performed on underground structures. In this study, we define the damage states and damage indices of a cut-and-cover box tunnel which is one of typical structures used in metro systems, under a seismic excitation from a series of inelastic frame analyses. Three damage states are defined in terms of the number of plastic hinges that develop within the structure. The damage index is defined as the ratio of the elastic moment to the yield moment. Through use of the proposed index, the inelastic behavior and failure mechanism of box tunnels can be simulated and predicted through elastic analysis. In addition, the damage indices are linked to free-field shear strains. Because the free-field shear strain can be easily calculated from a 1D site response analysis, the proposed method can be readily used in practice. Further studies are needed to determine the range of shear strains and associated uncertainties for various types of tunnels and site profiles. However, the inter-linked platform of damage state - damage index - shear wave velocity - shear strain provides a novel approach for estimating the inelastic response of tunnels, and can be widely used in practice for seismic designs.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.9
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• pp.1248-1256
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• 1993

The propagation and delay properties in opical fiber are particularly attractive because digital signal processing and conventional analog signal processing techniques such as those using surface acoustic wave devices are limited In their usefulness for signal bandwidth exceeding one or two GHz, although they are very effective at lower frequencies. Since an accurate, low loss and short time delay elements can be obtained by using such an optical fiber, optical signal precessing has attracted much attention for high speed and broad-band signal precessing in particular channel separation filtering for optical FDM signals. In this paper, we consider a coherent optical lattice filter, which uses coherent light sources and consists of directional couplers and optical fiber delay elemnts. The optical fiber fitters are more restricted than the usual digital filters. The reasons are as follows. 1) the coupling coefficients of directional couplers are restricted to the number between 0 and 1. 2) optical signal E(complex amplitude) is divided into J If-$\boxUl$ and J L/7$\div$$\boxUl$ at the directional coupler. Considering these restrictions and in this case all the coupling coefficients of summing and branching elements are set to be equal, we have given design formulae for optical lattice filter, which make the best use of optical signal energy.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.4
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• pp.504-510
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• 2009

Recently, personalized-adaptive services became the center of interest in the world. However the services about music are not widely diffused out. That is because the analyzing of music information is more difficult than analyzing of text information. In this paper, we propose a music recommendation system which provides personalized services. The system keeps a user's listening list and analyzes it to select pieces of music similar to the user's preference. For analysis, the system extracts properties from the sound wave of music and the time when the user listens to music. Based on the properties, a piece of music is mapped into a point in the property space and the time is converted into the weight of the point. At this time, if we select and analyze the group which is selected by user frequently, we can understand user's taste. However, it is not easy to predict how many groups are formed. To solve this problem, we apply the K-means clustering algorithm to the weighted points. We modified the K-means algorithm so that the number of clusters is dynamically changed. This manner limits a diameter so that we can apply this algorithm effectively when we know the range of data. By this algorithm we can find the center of each group and recommend the similar music with the group. We also consider the time when music is released. When recommending, the system selects pieces of music which is close to and released contemporarily with the user's preference. We perform experiments with one hundred pieces of music. The result shows that our proposed algorithm is effective.

• Journal of Preventive Medicine and Public Health
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• v.46 no.1
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• pp.19-27
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• 2013

Objectives: This study was conducted to investigate the relationship between heat-related illnesses developed in the summer of 2012 and temperature. Methods: The study analyzed data generated by a heat wave surveillance system operated by the Korea Centers for Disease Control and Prevention during the summer of 2012. The daily maximum temperature, average temperature, and maximum heat index were compared to identify the most suitable index for this study. A piecewise linear model was used to identify the threshold temperature and the relative risk (RR) above the threshold temperature according to patient characteristics and region. Results: The total number of patients during the 3 months was 975. Of the three temperature indicators, the daily maximum temperature showed the best goodness of fit with the model. The RR of the total patient incidence was 1.691 (1.641 to 1.743) per $1^{\circ}C$ after $31.2^{\circ}C$. The RR above the threshold temperature of women (1.822, 1.716 to 1.934) was greater than that of men (1.643, 1.587 to 1.701). The threshold temperature was the lowest in the age group of 20 to 64 ($30.4^{\circ}C$), and the RR was the highest in the ${\geq}65$ age group (1.863, 1.755 to 1.978). The threshold temperature of the provinces ($30.5^{\circ}C$) was lower than that of the metropolitan cities ($32.2^{\circ}C$). Metropolitan cities at higher latitudes had a greater RR than other cities at lower latitudes. Conclusions: The influences of temperature on heat-related illnesses vary according to gender, age, and region. A surveillance system and public health program should reflect these factors in their implementation.

• Analytical Science and Technology
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• v.25 no.5
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• pp.265-272
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• 2012

Okamoto cavity was modified to generate high power (2.45 GHz, 2 kW) He, N2 and Ar plasmas with WR-340 waveguide. Many factors which influence to the plasma generation were optimized and investigated for the spectroscopic properties of the He plasma generated. Some of the important factors are the diameter of the inner conductor, the distance between the inner and outer conductors and the distance between the tip of the inner conductor and the torch. After optimization for the He, two torches (a commercial mini torch for ICP and a tangential flow torch made locally) were compared and showed similar results for the helium plasma gas flow of 25 L/min~30 L/min. A tall torch (extended) was used to block the air in-flow and reduced the background intensity at 340 nm region (NH band). Emission intensity was measured for determination of halogen element in the aqueous solution with power and carrier gas flow rate. Electron number density and the excitation temperature were on the order of $3.67{\times}10^{11}/cm^3$ and 4,350 K, respectively. These values are similar or a bit smaller than other microwave plasmas. It has been possible to analyze aqueous samples. The detection limit for Cl (479.45 nm) was obtained to be 116 mg/L and needs analytical optimization for the better performance.

• Journal of Biomedical Engineering Research
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• v.20 no.4
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• pp.451-459
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• 1999

During the electromyographic evaluation for the diagnosis of neuropathy, presence for site of lesion could be predicted by a detection of denervation potentials such as fibrillation potentials or positive sharp waves in a group of muscles. Unfortunately, since denervation potentials are distinguished by examiner's experience, it is possible to make mistake identifying endplate spikes as a denervation potential. The aim of the study was to extract parameters to make an algorithm for quantitative distinction between denervation potentials and endplate spikes. It will help to minimize the examiner's bias and to localize the site of lesion thus increase the reliability on EMG diagnosis. There types of signals, endplate spike, fibrillation potential and positive sharp wave were obtained from the EDB(extensor digitorum brevis) muscle using then neuropathic patients. Eight parameters such as duration, area, slope, peak-to-peak amplitude, positive peak negative peak amplitude, ratio of positive to negative peak amplitude, and number of phase were extracted and compared. As a results, peak-to-peak amplitude, positive peak amplitude, ratio of positive to negative peak amplitude showed statistically significant differences between endplate spikes and denervation potentials. It was concluded that those parameters could be used to establish an algorithm which will improve the accuracies in automated quantitative EMG diagnosis.

• Sleep Medicine and Psychophysiology
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• v.5 no.2
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• pp.119-133
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• 1998

Attentional processes facilitate cognitive and behavioral performance in several ways. Attention serves to reduce the amount of information to receive. Attention enables humans to direct themselves to appropriate aspects of external environmental events and internal operations. Attention facilitates the selection of salient information and the allocation of cognitive processing appropriate to that information. Attention is not a unitary process that can be localized to a single neuroanatomical region. Before the cortical registration of sensory information, activation of important subcortical structures occurs, which is called as an orienting response. Once sensory information reaches the sensory cortex, a large number of perceptual processes occur, which provide various levels of perceptual resolution of the critical features of the stimuli. After this preattentional processing, information is integrated within higher cortical(heteromodal) systems in inferior parietal and temporal lobes. At this stage, the processing characteristics can be modified, and the biases of the system have a direct impact on attentional selection. Information flow has been traced through sensory analysis to a processing stage that enables the new information to be focused and modified in relation to preexisting biases. The limbic and paralimbic system play significant roles in modulating attentional response. It is labeled with affective salience and is integrated according to ongoing pressures from the motivational drive system of the hypothalamus. The salience of information greatly influences the allocation of attention. The frontal lobe operate response selection system with a reciprocal interaction with both the attention system of the parietal lobe and the limbic system. In this attentional process, the search with the spatial field is organized and a sequence of attentional responses is generated. Affective, motivational and appectitive impulses from limbic system and hypothalamus trigger response intention, preparation, planning, initiation and control of frontal lobe on this process. The reticular system, which produces ascending activation, catalyzes the overall system and increases attentional capacity. Also additional energetic pressures are created by the hypothalamus. As psychophysiological measurement, skin conductance, pupil diameter, muscle tension, heart rate, alpha wave of EEG can be used. Event related potentials also provide physiological evidence of attention during information process. NI component appears to be an electrophysiological index of selective attention. P3 response is developed during the attention related to stimulus discrimination, evaluation and response.

• Journal of the Korean Chemical Society
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• v.30 no.1
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• pp.51-56
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• 1986

Polarographic behavior of cadmium(II) and copper (II) complexes of 1,5-diphenylcarbohydrazide in dimethylsulfoxide have been investigated by the DC polarography. The reduction processes are estimated as follows; Cd(II)${\cdot}$DPH Complex$\frac{e^-}{(E_{\frac{1}{2}}=-0.12V)}$${\to}$Cd(I)${\cdot}$DPH Complex. Cd(I)${\cdot}$DPH Complex$\frac{e^-}{(E_{\frac{1}{2}}=-0.74V)}$${\to}$Cd(Hg) + nDPH. Cu(II)${\cdot}$DPH Complex$\frac{e^-}{(E_{\frac{1}{2}}=-0.44V)}$${\to}$Cu(I)${\cdot}$DPH Complex. Cu(I)${\cdot}$DPH Complex$\frac{e^-}{(E_{\frac{1}{2}}=-0.84V)}$${\to}$Cu(Hg) + nDPH. The limiting currents of all reduction wave are irreversible. The number of ligand and the dissociation constant for Cu(I)${\cdot}$1.5-diphenylcarbohydrazide complex were found to be 2 and 5.12 ${\times}10^{-8}$, respectively. All reduction waves of complexes are irreversible. Based on the experimental results, the polarographic reductions of complexes in dimethylsulfoxide solution occurred in two one-electron steps.