• Annals of Clinical Neurophysiology
• /
• v.13 no.2
• /
• pp.93-96
• /
• 2011

We present a recordings of 37-year-old woman with simultaneous ictal scalp and subdural electrodes. The ictal rhythm on subdural electrocorticography (ECoG) started earlier (median 24.5 sec) and ended later (median 2.0 sec) compared to ictal rhythm on scalp EEG. Eight ictal ECoG recordings were well localized to left temporal area, whereas ictal scalp EEG recordings were not. Our case shows the obvious timing relations between two recordings, and different electrophysiologic information about localization of ictal onset zone.

• Journal of Sensor Science and Technology
• /
• v.21 no.2
• /
• pp.156-166
• /
• 2012

Over the past 15 years productive BCI research programs have arisen. Current mainstream EEG electrode setups permit efficient recordings but most of electrodes has the disadventages of need for skin preparation and gel application to correctly record signals. The new gel-free probe was adapted for EEG recording and it can be fixed to the scalp with the micro needle without neuro-gel. It use standard EEG cap for wearing electrodes on scalp so it is compatible with standard EEG electrodes. A comparison between electrode characteristics is achieved by performing simultaneous recordings with the gel electrodes and gel-free probe placed in parallel scalp positions on the same anatomical regions. The quality of EEG recordings for all two types of experimental conditions is similar for gel-electrodes and gel-free probe. Subjects also reported not having special tactile sensations associated with wearing of gel-free probes. According to our results, it is expected that gel-free probe can be adapted to BCI, BMI(Brain Machine Interface), HMI(Human Machine Interface) because of its simple application and comfortable wearing process.

• Proceedings of the KOSOMBE Conference
• /
• v.1998 no.11
• /
• pp.145-146
• /
• 1998

A planar-type silicon microelectrode array has been fabricated and used successfully in obtaining simultaneous multichannel recordings from peripheral nerve of invertebrates. This paper demonstrates that planar-type semiconductor electrode arrays are useful for studying traveling wave properties of action potential.

• Journal of Biomedical Engineering Research
• /
• v.22 no.2
• /
• pp.145-150
• /
• 2001

대뇌 피질에 삽입하여 깊이에 따라 신경 신호를 기록하기 위한 탐침형 반도체 미세전극 어레이(depth-type silicon microelectrode array, 일명 SNU probe)를 제작하였다. 붕소를 확산시켜 생성된 고농도 p-type doping된 p＋ 영역을 습식식각 정지점으로 사용하는 기존의 방법과 달리 실리콘 웨이퍼의 앞면을 건식식각하여 원하는 탐침 두께만큼의 깊이로 트렌치(trench)를 형성한 후 뒷면을 습식식각하는 방법으로 탐침 형태의 미세 구조를 만들었다. 제작된 반도체 미세전극 어레이의 탐침 두께는 30 $\mu\textrm{m}$이며 실리콘 건식식각을 위한 마스크로 6 $\mu\textrm{m}$ 두께의 LTO(low temperature oxide)를 사용하였다. 탐침의 두께는 개발된 본 공정을 이용해서 5~90 $\mu\textrm{m}$ 범위까지 쉽게 조절할 수 있었다. 탐침의 두께를 보다 쉽게 조절할 수 있게 됨에 따라 여러 신경조직에 필요한 다양한 구조의 반도체 미세전극 어레이를 개발할 수 있게 되었다. 본 공정을 이용해서 개발된 4채널 SUN probe를 사용하여 흰쥐의 제1차 체감각 피질에서 4채널 신경 신호를 동시에 기록하였으며, 전기적 특성검사에서 기존의 탐침형 반도체 미세전극, 텅스텐 전극과 대등하거나 우수한 신호대 잡음비(signal to noise ratio, SNR)특성을 가짐을 확인하였다.

• Journal of Distribution Science
• /
• v.20 no.1
• /
• pp.109-114
• /
• 2022

Purpose: The purpose of this study is to confirm that multichannel distribution strategies may be used for cultural and artistic products such as musicals, just as for general consumer goods, through a case study on the distribution strategy for a musical title. In addition, a distribution strategy for cultural and artistic products is proposed based on the analysis of the case. Research design, data, and methodology: Qualitative research methods, such as case study research and in-depth interviews, were used in this study. Results: The case study of the Korean musical Myeongdong Romance confirmed that multichannel distribution strategies may be used for musicals, including performances at theaters, Naver TV screenings (a service linked to an Internet portal), LGU+ screenings (an IPTV and OTT media service), DVD releases, and screenings of recordings of Romance Hall performances. Conclusion: For cultural and artistic products such as musicals, distribution channels can be diversified to incorporate the simultaneous use of multiple channels. New cases involving other cultural and artistic products and services to which this distribution strategy is applicable may be identified, and the strategy may be implemented along with new technologies to reduce costs further.

• Journal of Biomedical Engineering Research
• /
• v.28 no.1
• /
• pp.17-23
• /
• 2007

Long-term potentiation (LTP) of synaptic transmission is the most widely studied model for learning and memory. However its mechanisms are not clearly elucidated and are a subject for intense investigation. Previous attempts to decipher cellular mechanisms and network properties involved a current-source density analysis (CSDA) of the LTP from small animal hippocampus measured with a limited number of microelectrodes (typically <3), only revealing limited nature of spatiotemporal dynamics. Recent advancement in multi-electrode array (MEA) technology allows continuous and simultaneous recordings of LTP with more than 60 electrodes. However CSDA via the standard Laplacian transform is still limited due to its relatively high sensitivity toward noise, inability of resolving overlapped current sources and sinks, and its requirement for tissue conductivity values. In this study, we propose a new methodology for improved CSDA. Independent component analysis and its joint use (i.e., Joint-ICA) are applied to extract spatiotemporal components of LTP. The results show that ICA and Joint-ICA are capable of extracting independent spatiotemporal components of LTP generators. The ICs of LTP indicate the reversing roles of current sources and sinks which are associated with LTP.

• Phonetics and Speech Sciences
• /
• v.14 no.3
• /
• pp.11-25
• /
• 2022

From simultaneous recordings of the external photoglottography, intra-oral air pressure (P_io), airflow and acoustic data from four native Seoul Korean speakers (2 male and 2 female), we have found that the two fricatives are not significantly different in glottal opening peak and airflow peak height either word-initially or word-medially and that the duration of aspiration is significantly reduced in word-medial /s/, compared to those in word-initial /s/, not in /s'/. We have also found that the duration of a high P_io plateau is significantly longer in /s/ than in /s'/ both word-initially and word-medially and that airflow resistance (R=P_io/U) at the onset and offset of a P_io plateau and at the time of airflow peak height is significantly higher in /s'/ than in /s/ across the contexts. However, the differences in P_io peak and F0 are not significant. In addition, the transition time to reach airflow peak height from the offset of a P_io plateau is found to be significantly longer in /s/ than /s'/ in both word-initial and word-medial positions. No significant differences in glottal opening peak and airflow peak height confirm that /s/ is specified as [-spread glottis] like /s'/. As for the other significant differences, we propose that /s/ is [-tense], and /s'/ [+tense].

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.3 no.1
• /
• pp.9-16
• /
• 2000

Purpose: The aim of this study was to determine how much acid exposure would occur in the proximal esophagus, both in normal and in patients with abnormal distal esophageal acid exposure. Methods: Fourty-six patients with suspected GER were classified into two groups, 24 patients with pathological distal reflux (group I); 22 patients with normal distal reflux (group II). The ambulatory dual-probe esophageal pH monitoring was performed for 18-24hr. The abnormal reflux was defined when the percent of time that pH was below 4.0 exceeded the 95th percentile of normal value. Results: The siginficant differences between distal and proximal esophageal pH recordings in group I persisted for all parameters except for the longest episode, but didn't persist in group II. At the distal esophageal site, the median percent time with pH<4.0 in group I was 19.3 and significantly higher than at proximal site. Half of patients with pathological distal reflux also had proximal acid reflux. Correlation coefficients between the distal and proximal esophageal sites in group I of the number of reflux episodes and time of the longest episode were 0.451 and 0.646 respectively. Conclusion: The 50 percent of patients with pathological distal acid reflux also had abnormal acid exposure in the proximal esophageal site. Therefore, we recommand simultaneous pH recordings from dual probe esophageal sites in children with gastroesophageal reflux.

• The Journal of Korean Academy of Prosthodontics
• /
• v.17 no.1
• /
• pp.7-21
• /
• 1979

This investigation was to analyse normal protrusive and lateral condylar pantographic records written on the sagittal plane and to study components of Fisher's angle and their interrelations. The purpose of this study was limited to (1) discussing the significance of sagittal pantographic record in diagnosis of occlusal disease and(2) basing for reasoning validity of measuring Fisher's angle which has been reported so far. As a result followings were concluded. 1. In each protrusive and lateral condylar movement path, five complicate factors such as initial straightness, distributed simple sigmoid type, simple curvature, initial tiny protruding convexity and tiny repeated sigmoid patterns were noted. Generally each condylar movement path was composed of two to three of these factors. 2. The distribution of positional interrelations of protrusive and lateral condylar paths could be divided into five categories; (a) protrusive-upper, (b) completely coinciding, (c) partially initial coinciding, (d) partially inverted crossing, and (e) completely inverting. Among these, protrusive path-upper positioned condyles were prevailed (79.2%). 3. The distribution of interrelations of protrusive and lateral condylar paths could be devided into five categories according to their distances in the course of movement. Among these, opening (95.8%) and paralleling (66.7%) were prevailing. 4. The involved number of characteristic heterogenous patterns of five categories in protrusive and lateral condylar movement recording relations at one simultaneous recordings was limited to three. However, in case of homogeneous patterns were repeated, usually three to four were included. 5. The maximum distance between protrusive and lateral condylar paths was 1.45mm at the location of 4mm advanced position from centric relation point and 3.90mm at the location of protrusive movement terminal. 6. It seemed to be that ,pantographic records should be consulted other clinical symptoms in order to make certain occlusion diagnosis. 7. At the present moment of investigation, expressing Fisher's angle as a degree revealed a lack due to inherent complexity of protrusive and lateral condylar movement paths. 8. The typical pattern of protrusive and lateral condylar paths written on a pantographic sagittal plate might be described as follows; (a) protrusive condylar path should be positioned upwardly, (b) both mainly be simple curvature, (c) interrelations mainly be opening or paralleling. 9. The mean amounts of separation between protrusive and lateral condylar movement path were $0.75{\pm}0.46$ at 4mm advanced location from centric relation and $1.74{\pm}0.64mm$ at the location of protrusive path terminal.

• The Korean Journal of Physiology
• /
• v.4 no.1
• /
• pp.19-28
• /
• 1970

In order to investigate the changes in the temperature regulation mechanism following ingestion of red pepper, twenty healthy man were given 2 gms of powdered red pepper each in 100 ml of water at room temperature, $20^{\circ}C$, Simultaneous recordings of temperature and electrical resistance of the skin of forehead were taken by means of Physiograph, using appropriate transducers. Temperature of various spots such as the cheek, upper tack and the forearm was also measured by the telethermometer at interval of two minutes. The results obtained were as follows: 1. Seventeen out of 20 subjects showed immediate rise in the skin temperature of the forehead, and 11 of them manifested the oscillating pattern of the skin temperature. The average of the largest peak amplitude was $0.58{\pm}0.355^{\circ}C$. 2. Even those who failed to show the immediate rise in the temperature did not keep the quiescence over 9 minutes, and delayed responses were revealed. 3. The rise in tile skin temperature is the favourable sign for the heat discipating mechanism only because the sweat glands are activated with the concomittant rise in the temperature of the skin. 4. There was a preceding or coincide fall in the electrical resistance of the skin, and it was also attributed to the glandular activity. 5. At rather cool room temperature, $20^{\circ}C$, no visible sweat was seen during the period of observation. Nevertheless it was obvious that latent activation of the sweat glands was triggered and the. threshold was lowered. This situation imitates the acclimatized condition in the hot environment, and it is likely to increase the tolerance in tropical climate from the view point of temperature regulation.