• Title/Summary/Keyword: frequency-response

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Induction of micronuclei in human, rabbit and dog lymphocytes irradiated in vitro with gamma radiation (사람, 토끼 및 개 유래 말초혈액 림프구의 미소핵을 이용한 방사선 피폭의 생물학적 선량측정)

  • Ryu, Si-yun;Kang, Bit-na;Kim, Ho-jun;Kim, Tae-hwan;Jeong, Kyu-sik;Kim, Se-ra;Lee, Hae-june;Kim, Sung-ho;An, Mi-Young
    • Korean Journal of Veterinary Research
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    • v.42 no.1
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    • pp.1-6
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    • 2002
  • The frequencies of gamma-ray-induced micronuclei (MN) in cytokinesis-blocked (CB) lymphocytes at several doses were measured in three donors of three species (human, rabbit, dog). Measurements performed after irradiation showed a dose-related increases in MN frequency in each of the donors studied. When analysed by linear-quadratic model the line of best fit was : human : $y=0.1184D+0.01867D^2+0.01$, rabbit : $y=0.0387D+0.00528D^2+0.01$ (y = number of MN/CB cells and D = irradiation dose in Gy). The relative sensitivity of rabbit lymphocytes compared with human lymphocytes was estimated by best fitting linear-quadratic model based on the radiation-induced MN data over the range from 0 Gy to 4 Gy. In the case of MN frequency with 0.2, the relative sensitivities of rabbit lymphocytes was 0.39. These data indicate that the induction of MN in rabbit CB cells following irradiation was much less sensitive to the MN induction effects of gamma-irradiation than those from human. The MN assay with dog lymphocytes was very difficult and time-consumed because the dog PHA-stimulated lymphocytes yielded cultures with very low level of CB cells formation in the condition of this experiment. Our in vitro radiobiological study confirmed that the cytogenetic response obtained in blood from rabbit can be utilized for application in environmental studies.

Effects of Eco-friendly Multi-enzyme on Diarrhea and Immune Response of weaned Pigs (친환경 복합효소제 첨가가 이유자돈의 설사 및 면역반응에 미치는 영향)

  • Min, Ye-Jin;Kim, Jun-Su;Kim, Sheen-A;Jang, Ki-Beom;Mun, Da-Ye;Kim, Byeong-Hyeon;Choe, Jee-Hwan;Song, Min-Ho
    • Korean Journal of Organic Agriculture
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    • v.26 no.1
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    • pp.151-161
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    • 2018
  • This study was designed to investigate the effects of multi-enzyme on diarrhea and immune responses of weaned pigs. A total 36 weaned pigs ($5.92{\pm}0.48kg\;BW$; 28 d old) were randomly allotted to 2 dietary treatments (3 pigs/pen, 6 replicates/treatment) in a randomized complete block design. The dietary treatments were a typical diet based on corn and soybean meal (CON) and CON with 0.1% multienzyme (Multi; mixture of ${\beta}-mannanase$, xylanase, ${\alpha}-amylase$, protease, ${\beta}-glucanase$, and pectinase). Pigs were fed their respective diets for 6 wk. Frequency of diarrhea, levels of packed cell volume (PCV), white blood cells (WBC), immunoglobulins, cortisol, tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), transforming growth $factor-{\beta}$ ($TGF-{\beta}$), and C-reactive protein (CRP) were measured. Multi group tended to decrease (p<0.1) diarrhea frequency than CON group during 2 wk after weaning. Lower values of PCV on d 3 (p<0.05) and d 7 (p<0.1) were found in Multi group compared with CON group. There were no significant differences on WBC number and immunoglobulin (Ig) M and A between Multi and CON groups. However, Multi group tended to increase (p<0.1) Ig G on d 7 than CON group. Moreover, Multi group showed modulated immune responses, indicated by decreased levels of cortisol (p<0.05) on d 7 and 14, $TNF-{\alpha}$ on d 3 (p<0.05) and d 7 (p<0.10), $TGF-{\beta}$ on d 2 (p<0.05) and d 7 (p<0.10), and CRP (p<0.10) on d 3 and 7 after weaning compared with CON group. Consequently, inclusion of multi-enzyme in diets for weaned pigs improved gut health and modulated immune responses of weaned pigs.

Influence of Housing Market Changes on Construction Company Insolvency (주택시장 변화가 규모별 건설업체 부실화에 미치는 영향 분석)

  • Jang, Ho-Myun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.5
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    • pp.3260-3269
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    • 2014
  • The construction industry has strong ties with other industries, and so construction company insolvency also has a strong influence on other industries. Prediction models addressing the insolvency of construction company have been well studied. Although factors contributing to insolvency must precede those of predictions of insolvency, studies on these contributing factors are limited. The purpose of this study is to analyze the influence of changes in the housing market on construction company insolvency by using the Vector Error Correction Model. Construction companies were divided into two groups, and the expected default frequency(EDF), which indicates insolvency of each company was measured through the KMV model. The results verified that 10 largest construction companies were in a better financial condition compared to relatively smaller construction companies. As a result of conducting impulse response analysis, the EDF of large companies was found to be more sensitive to housing market change than that of small- and medium-sized construction companies.

An Energy-Efficient Concurrency Control Method for Mobile Transactions with Skewed Data Access Patterns in Wireless Broadcast Environments (무선 브로드캐스트 환경에서 편향된 엑세스 패턴을 가진 모바일 트랜잭션을 위한 효과적인 동시성 제어 기법)

  • Jung, Sung-Won;Park, Sung-Geun;Choi, Keun-Ha
    • Journal of KIISE:Databases
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    • v.33 no.1
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    • pp.69-85
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    • 2006
  • Broadcast has been often used to disseminate the frequently requested data efficiently to a large volume of mobile clients over a single or multiple channels. Conventional concurrency control protocols for mobile transactions are not suitable for the wireless broadcast environments due to the limited bandwidth of the up-link communication channel. In wireless broadcast environments, the server often broadcast different data items with different frequency to incorporate the data access patterns of mobile transactions. The previously proposed concurrency control protocols for mobile transactions in wireless broadcast environments are focused on the mobile transactions with uniform data access patterns. However, these protocols perform poorly when the data access pattern of update mobile transaction are not uniform but skewed. The update mobile transactions with skewed data access patterns will be frequently aborted and restarted due 4o the update conflict of the same data items with a high access frequency. In this paper, we propose an energy-efficient concurrence control protocol for mobile transactions with skewed data access as well as uniform data access patterns. Our protocol use a random back-off technique to avoid the frequent abort and restart of update mobile transactions. We present in-depth experimental analysis of our method by comparing it with existing concurrency control protocols. Our performance analysis show that it significantly decrease the average response time, the amount of upstream and downstream bandwidth usage over existing protocols.

Experiment and Simulation of Acoustic Detection for the Substitute for Sunken Hazardous and Noxious Substances Using the High Frequency Active Sonar (고주파 능동소나를 이용한 저층 침적 위험유해물질 대체물질 음향 탐지 실험 및 모의)

  • Han, Dong-Gyun;Seo, Him Chan;Choi, Jee Woong;Lee, Moonjin
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.4
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    • pp.459-466
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    • 2018
  • Hazardous and Noxious Substances (HNS) are defined as substances that are likely to create a significant impact on human health and marine ecosystem when they are released into the marine environment. Recently, as the volume of HNS transported by ships increases, the rate of leakage accidents also increases. Therefore, research should be conducted to control and monitor sunken materials from the viewpoint of technology development for hazardous material leakage accident response. In this paper, acoustic detection experiments were carried out using HNS substitute materials in order to confirm the possibility of acoustic detection of sunken HNS on the sediment. The castor oil, which has a similar acoustic impedance with chloroform, is used as a substitute. 200 kHz high frequency signals were used to discriminate the reflected signals and measure reflection loss from the interface between water and castor oil. The reflection loss measured is in good agreement with the modeling results, showing a possibility of acoustic detection for sunken HNS.

Development of daily spatio-temporal downscaling model with conditional Copula based bias-correction of GloSea5 monthly ensemble forecasts (조건부 Copula 함수 기반의 월단위 GloSea5 앙상블 예측정보 편의보정 기법과 연계한 일단위 시공간적 상세화 모델 개발)

  • Kim, Yong-Tak;Kim, Min Ji;Kwon, Hyun-Han
    • Journal of Korea Water Resources Association
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    • v.54 no.12
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    • pp.1317-1328
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    • 2021
  • This study aims to provide a predictive model based on climate models for simulating continuous daily rainfall sequences by combining bias-correction and spatio-temporal downscaling approaches. For these purposes, this study proposes a combined modeling system by applying conditional Copula and Multisite Non-stationary Hidden Markov Model (MNHMM). The GloSea5 system releases the monthly rainfall prediction on the same day every week, however, there are noticeable differences in the updated prediction. It was confirmed that the monthly rainfall forecasts are effectively updated with the use of the Copula-based bias-correction approach. More specifically, the proposed bias-correction approach was validated for the period from 1991 to 2010 under the LOOCV scheme. Several rainfall statistics, such as rainfall amounts, consecutive rainfall frequency, consecutive zero rainfall frequency, and wet days, are well reproduced, which is expected to be highly effective as input data of the hydrological model. The difference in spatial coherence between the observed and simulated rainfall sequences over the entire weather stations was estimated in the range of -0.02~0.10, and the interdependence between rainfall stations in the watershed was effectively reproduced. Therefore, it is expected that the hydrological response of the watershed will be more realistically simulated when used as input data for the hydrological model.

Effects of the Combination of Oxygen and Color Light on Stress Relaxation: Psychological and Autonomic Responses (산소와 색채 조명 자극의 조합이 스트레스 완화에 미치는 효과: 심리 및 자율신경계 반응을 중심으로)

  • Jang, Eun-Hye;Kim, Ah-Young;Jang, Yongwon;Kim, Bo-Seong;Choi, Yong-Bok;Kim, Seung-Chul;Lee, Sang-Kone;Kim, Seunghwan
    • Science of Emotion and Sensibility
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    • v.22 no.1
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    • pp.55-64
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    • 2019
  • Stress is accompanied by changes in the responses of the autonomic nervous system, and the heart rate variability (HRV) index is a quantitative marker that reflects autonomic responses induced by stressors. In this study, we observed changes in the autonomic responses induced by combinations of 30% oxygen administration and color light for stress relaxation. In all, 42 participants produced stress symptoms over the preceding two weeks, as rated on the stress response scale. After stress assessment, they were exposed to three therapeutic conditions, and electrocardiogram (ECG) signals were recorded before, during, and after therapy. The three therapy conditions consisted of only 30% oxygen administration with white light, a combination of 30% oxygen and orange light, and a combination of 30% oxygen and blue light. The HRV indices extracted from ECG signals were heart rate (HR), the standard deviation of the RR interval (SDNN), the mean square root of consecutive RR interval difference values (RMSSD), the low frequency component of HRV (LF), the high frequency component (HF), and the LF/HF ratio. These indicators were used to compare mean values before and after therapy. The results showed that HR and the LF/HF ratio were significantly lower after therapy than before it. In particular, the condition with 30% oxygen and blue light yielded significantly greater RMSSD and HF increases, as well as decreases in LF/HF ratio than in other two conditions. Our results suggest that therapy with 30% oxygen and blue light is the most effective for the relaxation of stress, which implies autonomic balance by parasympathetic activation.

A research on the emotion classification and precision improvement of EEG(Electroencephalogram) data using machine learning algorithm (기계학습 알고리즘에 기반한 뇌파 데이터의 감정분류 및 정확도 향상에 관한 연구)

  • Lee, Hyunju;Shin, Dongil;Shin, Dongkyoo
    • Journal of Internet Computing and Services
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    • v.20 no.5
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    • pp.27-36
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    • 2019
  • In this study, experiments on the improvement of the emotion classification, analysis and accuracy of EEG data were proceeded, which applied DEAP (a Database for Emotion Analysis using Physiological signals) dataset. In the experiment, total 32 of EEG channel data measured from 32 of subjects were applied. In pre-processing step, 256Hz sampling tasks of the EEG data were conducted, each wave range of the frequency (Hz); Theta, Slow-alpha, Alpha, Beta and Gamma were then extracted by using Finite Impulse Response Filter. After the extracted data were classified through Time-frequency transform, the data were purified through Independent Component Analysis to delete artifacts. The purified data were converted into CSV file format in order to conduct experiments of Machine learning algorithm and Arousal-Valence plane was used in the criteria of the emotion classification. The emotions were categorized into three-sections; 'Positive', 'Negative' and 'Neutral' meaning the tranquil (neutral) emotional condition. Data of 'Neutral' condition were classified by using Cz(Central zero) channel configured as Reference channel. To enhance the accuracy ratio, the experiment was performed by applying the attributes selected by ASC(Attribute Selected Classifier). In "Arousal" sector, the accuracy of this study's experiments was higher at "32.48%" than Koelstra's results. And the result of ASC showed higher accuracy at "8.13%" compare to the Liu's results in "Valence". In the experiment of Random Forest Classifier adapting ASC to improve accuracy, the higher accuracy rate at "2.68%" was confirmed than Total mean as the criterion compare to the existing researches.

Road Patrol Strategy based on Pothole Occurrence Characteristics considering Rainfall Effects (우천에 따른 포트홀 발생 특성을 고려한 도로순찰 전략)

  • Han, Daeseok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.12
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    • pp.603-611
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    • 2020
  • Potholes on the road directly affect drivers' safety, satisfaction, and vehicle damage. Thus, real-time detection and response are required. Increasing frequency of patrols allows for potholes to be detected and responded to quickly, but this takes much manpower, money, and time. In addition, potholes have different occurrence characteristics depending on the rain conditions, so it is necessary to consider the optimal frequency from an economic and road-service perspective. Therefore, a quantitative analysis was done on the effects of rainfall on the occurrence characteristics of potholes. Information on the persistence, impact of rainfall intensity, and weather information was collected over a long period. Based on the results, a risk-based, optimized, and changeable road-patrol strategy is presented. The analysis results show that the probability of pothole occurrence increases by 2.4 times in rainy weather. Furthermore, the impact continues for 3 days even after the rain stops. The probability of pothole occurrence increases by 0.46% per 1 mm of rainfall, and the occurrence characteristics react sensitively to even a small amount of rain of around 1 mm. It was concluded that road patrol is required at least once every three days for an effect-free period, while twice a day is needed for the "sphere of influence" period to achieve a 95% reliability level.ys for effect-free period, while twice a day for sphere of influence period to satisfy 95% reliability level.

A Recommendation of the Technique for Measurement and Analysis of Passive Surface Waves for a Reliable Dispersion Curve (신뢰성 있는 분산곡선의 결정을 위한 수동표면파 측정 및 분석기법의 제안)

  • Yoon, Sung-Soo
    • Journal of the Korean Geotechnical Society
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    • v.23 no.2
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    • pp.47-60
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    • 2007
  • Conventional active surface wave measurements performed using a transient or continuous source are often limited in the maximum depth of penetration due to the difficulty of generating low-frequency energy with reasonably portable sources. This limitation may inhibit accurate seismic site response calculations because of the inability to define deeper subsurface structure. By measuring surface wave generated by passive sources including microtremors and cultural noise, it is possible to overcome this problem and develop soil stiffness profiles to much larger depth. Reliability of dispersion estimates from the passive surface wave measurements is critical to present reliable shear wave velocity profiles and can be improved by the measurements and analyses of passive surface waves based on correct understanding of systematic errors included in passive dispersion data. In this study, the systematic errors caused by poor wavenumber resolution and energy leakage into sidelobes in passive tests are mainly explored. Recommendations for reliable passive surface wave measurements and dispersion estimates are presented and illustrated at a site in San Jose, California, U.S.