• Safety and Health at Work
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• v.1 no.2
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• pp.140-148
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• 2010

Objectives: Determining the work-relatedness of lung cancer developed through occupational exposures is very difficult. Aims of the present study are to develop a decision tree of occupational lung cancer. Methods: 153 cases of lung cancer surveyed by the Occupational Safety and Health Research Institute (OSHRI) from 1992-2007 were included. The target variable was whether the case was approved as work-related lung cancer, and independent variables were age, sex, pack-years of smoking, histological type, type of industry, latency, working period and exposure material in the workplace. The Classification and Regression Test (CART) model was used in searching for predictors of occupational lung cancer. Results: In the CART model, the best predictor was exposure to known lung carcinogens. The second best predictor was 8.6 years or higher latency and the third best predictor was smoking history of less than 11.25 pack-years. The CART model must be used sparingly in deciding the work-relatedness of lung cancer because it is not absolute. Conclusion: We found that exposure to lung carcinogens, latency and smoking history were predictive factors of approval for occupational lung cancer. Further studies for work-relatedness of occupational disease are needed.

• Korean Journal of Clinical Laboratory Science
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• v.38 no.3
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• pp.224-230
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• 2006

Up to now, there have been rare clinical studies on leaders and aerobics athletes. To get the useful data for protecting from auditory disorder, we selected 15 female aerobics leaders (experimental group) and 15 females (control group) unexperienced in aerobics and a without neurological and octolaryngological disorder. The average age was $34.87{\pm}8.80$ (experimental group) and $34.07{\pm}8.45$ (control group) years, and the average career of an aerobics leader (experimental group) was $8.33{\pm}4.73$ years. We measured the auditory evoked potential (AEP) of the two groups treated with 70, 75 and 85 dB intensity from January 2006 to May 2006 and analyzed the absolute latency (AL) and interpeak latency (IPL) by the SPSS/pc+ 12.0 program. In the comparison of the AL between the experimental group and the control group according to intensity, both ears treated with 70 and 75 dB had a significant difference (p<0.05) in the I, III, V wave and in the I, V wave respectively, and the experimental group treated with 85 dB showed a difference in the I, III, V wave (left ear) and in the I wave (right ear) respectively. The IPL of the two groups treated with various intensities had no prolongation. In the comparison of the AL between the experimental group and the control group according to ages, the experimental group in their 20s treated with 70 dB showed a significant difference (p<0.05) in the V wave (left ear) and in the I, III, V wave (right ear), and the experimental group in their 20s treated with 75 dB in the I, III wave (left ear) and in I, III, V wave (right ear), and experimental group in their 20s treated with 85 dB in the V wave (left ear) and in the III, V wave (right ear). The experimental group in their 30s treated with 70 dB had a significant difference (p<0.05) only in the V wave (right ear). Only in the IPL of subjects in their 20s treated with 85 dB, III-V and I-V of both ears was extended. In the comparison of the AL and IPL according to career, there was no significant difference between the two groups. From this results, we concluded that the lower sound intensity (70 dB) showed a more significant difference in the experimental group than the control group. We concluded that the leader of aerobics exposed to louder sounds than normal people are affected by auditory neurological and octolaryngological disorders. So we think that the leaders of aerobics need to control the noise level for protecting themselves against a disease.

• Annals of Clinical Neurophysiology
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• v.19 no.1
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• pp.13-19
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• 2017

Background: Median F-wave latencies are physiologically shorter than ulnar latencies, but they are often longer relative to ulnar latencies in carpal tunnel syndrome (CTS). This study aimed to investigate the value of absolute F-waves and relative latency changes compared to ulnar latencies in the diagnosis of CTS. Methods: F-wave latencies of median and ulnar nerves in 339 hands from 339 patients with CTS and 60 hands from 60 control subjects were investigated. Mean F-wave minimal latencies of median and ulnar nerves were compared between groups. Patients were further divided into subgroups based on Canterbury grading and then analyzed using F-wave latency differences (FWLD) and F-wave ratio (FWR). Results: Of 339 hands in the CTS group, 236 hands exhibited F-wave inversion based on the FWLD criterion and 277 hands had F-wave inversion based on the FWR criterion. F-wave inversion had a sensitivity of 81.7% using the FWR criterion to diagnose CTS. The mean FWLD and FWR were significantly greater in all patient subgroups compared to the control group (p < 0.001). In addition, mean FWLD and FWR showed significant correlations (r = -0.683 and r = 0.674, respectively, p < 0.001) with disease severity. Conclusions: F-wave studies are effective supplementary diagnostic tools comparing to other standard electrophysiologic criteria for screening patients with CTS.

• Journal of Audiology & Otology
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• v.24 no.1
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• pp.10-16
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• 2020

Background and Objectives:The blockage of adenosine receptors by caffeine changes the levels of neurotransmitters. These receptors are present in all parts of the body, including the auditory and vestibular systems. This study aimed to evaluate the effect of caffeine on evoked potentials using auditory brainstem responses (ABRs) and cervical vestibular-evoked myogenic potentials (cVEMPs) in a double-blind placebo-controlled study. Subjects and Methods: Forty individuals (20 females and 20 males; aged 18-25 years) were randomly assigned to two groups: the test group (consuming 3 mg/kg pure caffeine powder with little sugar and dry milk in 100 mL of water), and the placebo group (consuming only sugar and dry milk in 100 mL water as placebo). The cVEMPs and ABRs were recorded before and after caffeine or placebo intake. Results: A significant difference was observed in the absolute latencies of I and III (p<0.010), and V (p<0.001) and in the inter-peak latencies of III-V and I-V (p<0.001) of ABRs wave. In contrast, no significant difference was found in cVEMP parameters (P13 and N23 latency, threshold, P13-N23 amplitude, and amplitude ratio). The mean amplitudes of P13-N23 showed an increase after caffeine ingestion. However, this was not significant compared with the placebo group (p>0.050). Conclusions: It seems that the extent of caffeine's effects varies for differently evoked potentials. Latency reduction in ABRs indicates that caffeine improves transmission in the central brain auditory pathways. However, different effects of caffeine on auditory- and vestibular-evoked potentials could be attributed to the differences in sensitivities of the ABR and cVEMP tests.

• Korean Journal of Audiology
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• v.24 no.1
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• pp.10-16
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• 2020

Background and Objectives:The blockage of adenosine receptors by caffeine changes the levels of neurotransmitters. These receptors are present in all parts of the body, including the auditory and vestibular systems. This study aimed to evaluate the effect of caffeine on evoked potentials using auditory brainstem responses (ABRs) and cervical vestibular-evoked myogenic potentials (cVEMPs) in a double-blind placebo-controlled study. Subjects and Methods: Forty individuals (20 females and 20 males; aged 18-25 years) were randomly assigned to two groups: the test group (consuming 3 mg/kg pure caffeine powder with little sugar and dry milk in 100 mL of water), and the placebo group (consuming only sugar and dry milk in 100 mL water as placebo). The cVEMPs and ABRs were recorded before and after caffeine or placebo intake. Results: A significant difference was observed in the absolute latencies of I and III (p<0.010), and V (p<0.001) and in the inter-peak latencies of III-V and I-V (p<0.001) of ABRs wave. In contrast, no significant difference was found in cVEMP parameters (P13 and N23 latency, threshold, P13-N23 amplitude, and amplitude ratio). The mean amplitudes of P13-N23 showed an increase after caffeine ingestion. However, this was not significant compared with the placebo group (p>0.050). Conclusions: It seems that the extent of caffeine's effects varies for differently evoked potentials. Latency reduction in ABRs indicates that caffeine improves transmission in the central brain auditory pathways. However, different effects of caffeine on auditory- and vestibular-evoked potentials could be attributed to the differences in sensitivities of the ABR and cVEMP tests.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.3
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• pp.384-389
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• 2003

A new two-step soft-output Viterbi algorithm (SOVA) decoder architecture is presented. A significant reduction in the decoding latency can be achieved through the use of the dual-port RAM in the survivor memory structure of the trace-back unit. The system complexity can be lowered due to the determination of the absolute value of the path metric differences inside the add-compare-select (ACS) unit. The proposed SOVA architecture was verified successfully by the functional simulation of Verilog HDL modeling and the FPGA prototyping. The SOVA decoder achieves a data rate very close to that of the conventional Viterbi Algorithm (VA) decoder and the resource consumption of the realized SOVA decoder is only one and a half times larger than that of the conventional VA decoder.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.37
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• pp.13.1-13.7
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• 2015

Background: This study evaluated Somatosensory evoked potentials (SEP), Quantitative sensory testing (QST), and thermography as diagnostic methods for nerve injury. Methods: From 2006 through 2011, 17 patients (mean age: 50.1 years) from ${\bigcirc}{\bigcirc}{\bigcirc}{\bigcirc}$ Hospital who sought care for altered sensation after dental implant treatment were identified. The mean time of objective assessment was 15.2 months after onset. Results: SEP of Inferior alveolar nerve(IAN) was $15.87{\pm}0.87ms$ on the normal side and $16.18{\pm}0.73ms$ on the abnormal side. There was delayed N20 latency on the abnormal side, but the difference was not statistically significant. In QST, the abnormal side showed significantly higher scores of the current perception threshold at 2 KHz, 250 Hz, and 5 Hz. The absolute temperature difference was $0.55^{\circ}C$ without statistically significance. Conclusion: These results indicate that QST is valuable as an objective method for assessment of nerve injury.

• Journal of Veterinary Clinics
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• v.17 no.2
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• pp.388-394
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• 2000

이 실험은 소형견종에 대한 정상 SEPs의 범위를 알아내기 위해 실시되었다. 임상증 상이 정상인 28두를 대상으로 자극점에서 channel 1 까지의 Pl(LPI), channel 1까지의 Nl (LN1), 자극점에서 channel 2가지의 Pl(TP1), channel 2까지의 N1(TNI)의 절대잠복기와 LP1-TN1` 의 파간잠복기를 알아내기 위해서 실시하였다. 이번 실험에서 LPI, LNI, TPI, TNI의 절대잠복기 (absolute latency)의 평균값은 2.69$\pm$0.31 msec, 4.91$\pm$0.49m/sec, 4.64$\pm$0.39 msec, 5.21$\pm$0.42 msec 띠었다. LP1과 TN1 사이의 파간절대잠복기의 핑균값은 2.52$\pm$7.19 msec 이었다. 측정 치들을 속도로 변환하였을 경우 다음과 같았다. 측, LPI, LNI. Tfl, TNI 그리고 LP1-TN1 에서의 속도의 평균값은 각각 93.11$\pm$ 8.58 m/sec, 50.99$\pm$ 5.36m/sec. 80.18$\pm$ sec, 71.31$\pm$4.79m/sec그리고 49.50$\pm$3.58m/sec 이었고. 71.66m/sec, 37.79m/sec, 65.75m/ sec, 59.33 m/sec, 40.55m/sec 의 최저속도를 초과하였을 때 정상범위로 간주하였다. LPI, LNI, TPI,TN1까지의 절대잠복기와 자극전극에 시 측정전극가지의 거리 사이에는 상관관계가 있었다 LP1, LN1, TP1, TN1의 상관계수는 각각 0.621, 0.494. 0.577,0.618 이었다 요추에서 기록된 SEPs갈은 LP1의 상관계수가 LN1 보다 높았으며 흉추에서 기록된 SEPs값은 TN1의 상관계수가 TP1보다 높았다. LP1과 TN1의 파간잠복기와 channel 1과 2의 거리차이와의 상관계수는 0.571이다. 따라서 LPI, LNI. TPI, TNI그리고 LPI-TNI 들의 최저속도를 이용 하여 척수 손상 여부를 판단할 수 있다고 생각된다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.2
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• pp.271-277
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• 2022

PBFT (Practical Byzantine Fault Tolerant) is a consensus algorithm that can achieve consensus by resolving unintentional and intentional faults in a distributed network environment and can guarantee high performance and absolute finality. However, as the size of the network increases, the network load also increases due to message broadcasting that repeatedly occurs during the consensus process. Due to the characteristics of the PBFT algorithm, it is suitable for small/private blockchain, but there is a limit to its application to large/public blockchain. Because PBFT affects the performance of blockchain networks, the industry should test whether PBFT is suitable for products and services, and academia needs a unified evaluation metric and technology for PBFT performance improvement research. In this paper, quantitative evaluation metrics and evaluation frameworks that can evaluate PBFT family consensus algorithms are studied. In addition, the throughput, latency, and fault tolerance of PBFT are evaluated using the proposed PBFT evaluation framework.

• Sleep Medicine and Psychophysiology
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• v.8 no.2
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• pp.121-128
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• 2001

Objectives: In narcoleptic patients diagnosed with ICSD (international classification of sleep disorders, 1990) criteria, nocturnal polysomnography, and MSLT (multiple sleep latency test), we tried to find characteristic features of quantitative electroencephalography (QEEG) in a wakeful state. Methods: We compared eight drug-free narcoleptic patients with sex- and age-matched normal controls, using computerized electroencephalographic mapping technique and spectral analysis. Absolute power, relative power, interhemispheric asymmetry, interhemispheric and intrahemispheric coherence, and mean frequency in each frequency band (delta, theta, alpha and beta) were measured and analyzed. Results: Compared with normal controls, narcoleptic patients showed decrease in monopolar interhemispheric coherence of alpha frequency bands in occipital ($O_1/O_2$), parietal ($P_3/P_4$), and temporal ($T_5/T_6$) areas and beta frequency band in the occipital ($O_1/O_2$) area. Monopolar intrahemispheric coherences of alpha frequency bands in left hemispheric areas ($T_3/T_5$, $C_3/P_3$ & $F_3/O_1$) decreased. Decrease of monopolar interhemispheric asymmetry of delta frequency band in the occipital ($O_1/O_2$) area was also noted. The monopolar absolute powers of beta frequency bands decreased in occipital ($O_2,\;O_z$) areas. Conclusion: Decreases in coherences of narcoleptic patients compared with normal controls may indicate fewer posterior neocortical interhemispheric neuronal connections, and fewer left intrahemispheric neuronal connections than normal controls in a wakeful state. Therefore, we suggest that abnormal neurophysiological sites of narcolepsy may involve complex areas such as neocortex and subcortex as well as the brainstem.