• Title/Summary/Keyword: frequency-response

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The Method of New Robust Inverse Filter Design in 2-Ch Audio System (2채널 오디오 시스템에서 전달계 변동에 강인한 역필터 설계 기법)

  • Park, Byoung-Uk;Kim, Hack-Yoon
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.1
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    • pp.185-192
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    • 2008
  • The crosstalk is the most serious problem in playing audio signals with more than two speakers. Usually an inverse filter is employed to remove such a Phenomenon. The LNS method, one of most effective design techniques for an inverse filter, has some advantages such as easy implementation and quick computation. However, the inverse filter designed by the LNS method is not easy to adapt immediately for the delivery system change since the pre-measured impulse response is used to design the filter. In this work, we present an adaptive algorithm for the inverse filter design. With the present algorithm. the inverse filter is initially designed by the LNS methods and continuously adjusted to cope with the delivery system changes. To verify the proposed method. some simulations were carried out and the results confirmed that the performance of the crosstalk calculation can be improved in entire frequency range.

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Induction of Local and General Analgesia by Electroacupuncture in Dogs (개에 있어서 침술에 의한 국소 및 전신마취에 관한 연구)

  • 남치주;서강문
    • Journal of Veterinary Clinics
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    • v.14 no.2
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    • pp.244-253
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    • 1997
  • This study was performed to evaluate the possibility of inducing analgesia by electroacupuncture stimulation at single acupoint or combined acupoints and to examine the analgesic effects following the combination of premedication and electroacupunrture analgesia(EA). Analgesia was induced by EA with the current of 1-4 volts and the frequency of 10-45 Hz to the acupoints Uown to be related to analgesia on the head/necIL axial part thoracic and pelvic limb. In Yi Feng acupoint of head/neck part pain responses were not disappeared after electroacupunrture stimulation to the head/necIL thoracic limbo thoraxl abdomen, loin, rear and pelvic limb. Pain responses were remained after EA of Tian Men-Tian Ping and Shen Yu arupoints of axial park whereas hypoalgesia was observed after EA of Tian Ping-Bai Hui acupoint in all parts of body. There was no analgesic effects after EA stimulation of the brachial plexus and Wai Kuan acupoint, whereas after EA stimulation of San Yang Lo, pain responses were disappeared in headfnecll, thoracic limb and pelvic limbo and in the other parts of body hypoalgesia was shown. In EA stimulation of Tsu San Li acupoint pain responses were disappeared in pelvic limb and in San Yin Chiao acupoint pain responses were disappeared in head/necIL thoracic and pelvic limb, and hypoalgesia was shown in abdomen. On the combination of San Yang Lo Pli Men) and San Yin Chiao (Pu Yan6 acupoints, pain response in heauneck was decreased in 5 minutes, whereas analgesia in thoracic and pelvic limb was induced after 20-30 minutes and in abdomen was noted after 50 minutes. The more frequrncy was increased, the more rapid analgesic e11%t was induced. The analgesic effects wert not good in laparotomy under EA at the combination of San Yang Lo (Xi Men) and San Yin Chiao (Pu Yang) arufoints. Enteroanastomosis could not be continued under acrpromazine, xylazine and diazepam with EA. However, under EA followed by tiletaminetzolazepam, the operation could be completed without additional anesthesia and the analgesic effects were good. There were no changes in clinical signs, hematological and serological values after combination of the premeditation of tiletamine+zolaEepam and EA. It is considered that EA alone is not suitable for the main surgery, but the combination method of EA and sedatives can be utilized in practice.

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A study on user satisfaction in TUI environment (TUI 환경의 유저 사용 만족도 연구)

  • Choi, heungyeorl;Yang, seungyong
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.11 no.4
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    • pp.113-127
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    • 2015
  • An interface in smart device environment is changing to TUI(touch user interface) environment where a system is being controlled by physical touch, differently from a system controlled through conventional mouse and keyboard. What is more important than anything else in this TUI environment is to implement interface in consideration of learn ability and cognitive constructivism according to user's experience. Therefore, now is the time when it is necessary to carry out various studies on smart content design process going a step farther together with discussing the details of user's experience factor. Hence, this study was intended to look into what effect a user's experiential traits had on the production of contents for the purpose of measures for improving TUI user satisfaction in order to effectively realize contents in smart environment. Results were yielded by using a statistical empirical analysis such as cross-tabulation analysis according to important variable and user, paired t-test, multiple response analysis, and preference frequency analysis of user preference on the basis of a survey. As a result, a system was presented for implementing DFSS(Design For Six Sigma) process. TUI experience factor can be divided into direct habitual experience, direct learning experience, indirect habitual experience, and indirect learning experience. And in the results of study, it was possible to find that the important variables of this study had a positive effect on the improvement of use satisfaction with contents on the whole according to the user convenience of smart contents. This study is expected to have a positive effect on efficient smart device-based contents production by providing objective information according to empirical analysis to smart media-based developer and designer and presenting a model for improving the changed TUI usability.

Impact shock and kinematic characteristics of the lower extremity's joint during downhill running (내리막 달리기의 충격 쇼크와 신체 관절의 운동학적 특징)

  • Ryu, Ji-Seon
    • Korean Journal of Applied Biomechanics
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    • v.15 no.4
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    • pp.117-129
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    • 2005
  • The purpose of this study was to characterize the impact shock wave and its attenuation, and the kinematic response of the lower extremity's joints to the impact shock during downhill running in which the lower extremity's extensor acts dominantly. For this study, fifteen subjects(mean age:$27.08{\pm}4.39$; mass:$76.30{\pm}6.60$; height:$177.25{\pm}4.11$) were required to run on the 0% grade treadmill and downhill grades of 7%, and 15% in random at speed of their preference. When the participant run, acceleration at the tibia and the sacrum and kinematic data of the lower extremity were collected for 20s so as to provide at least 5 strides for analysis at each grade. Peak impact accelerations were used to calculate shock attenuation between the tibia and sacrum in time domain at each grade. Fast Fourier transformation(FFT) and power spectral density(PSD) techniques were used to analyze impact shock factors and its attenuation in the frequency domain. Joint coordinate system technique was used to compute angular displacement of the ankle and knee joint in three dimension. The conclusions were drawn as fellows: 1. Peak impact accelerations of the tibia and sacrum in downhill run were greater than that of 0% grade run, but no significant between conditions. Peak shock of PSD resembled also in pattern of peak impact acceleration. The wave of impact shock attenuation between the tibia and sacrum decreased with increasing grade, but didn't find a significant difference between grade conditions. 2. Adduction/abduction, flexion/extention, and internal/external rotation of the ankle and knee joints at support phase between grade conditions didn't make much difference. 3. At grade of 7% and 15%, there were relationship between the knee of the flexion/extension movement and peak impact acceleration during heel strike and found also it in the ankle of plantar/dorsiflexion at grade of 15%.

TheMagneticFieldDistributionAnalysisandOpticalCharacteristicsfortheRing-ShapedElectrodelessFluorescentLamp. (환형무전극형광램프의자계분포해석과광학적특성에관한연구)

  • Jo Ju-Ung;Lee Jong-Chan;Choi Yong-Sung;Kim Yong-Kap;Park Dae-Hee
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.54 no.6
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    • pp.255-261
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    • 2005
  • Recently, the RF inductive discharge or inductively coupled plasma continues to attract growing attention as an effective plasma source in many industrial applications, the best known of which are plasma processing and lighting technology. To the point of lighting sources, the ring-shaped electrodeless fluorescent lamps utilizing an inductively coupled plasma have been objects of interest and research during the last decades, mainly because of their potential for extremely long life, high lamp efficacies, rapid power switching response. In this paper, maxwell 3D finite element analysis program (Ansoft) was used to obtain electromagnetic properties associated with the coil and nearby structures. The electromagnetic emitting properties were presented by 3D simulation software operated at 250 kHz and some specific conditions. The electromagnetic field in the ferrite core was shown to be high and symmetric. An LS-100 luminance meter and a Darsa-2000 spectrum analyzer were used in the experiment. According to data on the lamp tested using high magnetic field ferrite, the optical and thermal wave fields were shown to be high around the ring-shaped electrodeless fluorescent lamp. The optical or light field was high at the center of the bulb rather than around the ferrite core. The light conditions of the bulb were assumed to be complex, depending on the condition of the filler gas, the volume of the bulb, and the frequency of the inverter. Our results have shown coupling between the gas plasma and the field of the light emitted to be nonlinear.

EMQT : A Study on Enhanced M-ary Query Tree Algorithm for Sequential Tag IDs (연속적인 태그 ID들을 위한 M-ary 쿼리 트리 알고리즘의 향상에 관한 연구)

  • Yang, Dongmin;Shin, Jongmin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38B no.6
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    • pp.435-445
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    • 2013
  • One of the most challenging issues in radio frequency identification (RFID) and near field communications (NFC) is to correctly and quickly recognize a number of tag IDs in the reader's field. Unlike the probabilistic anti-collision schemes, a query tree based protocol guarantees to identify all the tags, where the distribution of tag IDs is assumed to be uniform. However, in real implements, the prefix of tag ID is uniquely assigned by the EPCglobal and the remaining part is sequentially given by a company or manufacturer. In this paper, we propose an enhanced M-ary query tree protocol (EMQT), which effectively reduces unnecessary query-response cycles between similar tag IDs using m-bit arbitration and tag expectation. The theoretical analysis and simulation results show that the EMQT significantly outperforms other schemes in terms of identification time, identification efficiency and communications overhead.

Association between Genetic Polymorphisms of the CYP2C19, CYP2D6 and Types of Sasang Constitutional Medicine (약물대사효소 CYP2C19, CYP2D6의 다형성과 사상체질의 관련성 연구)

  • Lee, Sang-Gyu;Kim, Hyun-Ju;Park, Hye-Jung;Lee, Jung-Ho;Kwon, Deog-Yun;Joo, Jong-Cheon;Choi, Sun-Mi;Lee, Hye-Suk;Kim, Yun-Kyung
    • The Journal of Korean Medicine
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    • v.28 no.1 s.69
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    • pp.51-62
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    • 2007
  • Objectives . The types of Sasang constitutional medicine (SCM) have definite effect on response to herbal drugs. The majority of human P45O dependent xenobiotic metabolism is carried out by polymorphic enzymes which can cause abolished, altered or enhanced metabolism. Therefore, we evaluated the relation of major CYP2C19, 2D6 polymorphism with Sasang types. Methods : 214 healthy subjects were recruited with informed consent; 172 among them had Sasang diagnosis by QSCC2. CYP2D6, 2C19 polymorphism were determined by PCR-RFLP method. Results : None of the Sasang types showed significant difference in CYP2D6, 2C19 polymorphism. However, the Tae-um type showed relatively low frequency of CYP2D6 $^{*}$10/$^{*}$10 polymorphisms with low activity (p=0.110). In the So-yang type, specific $^{*}$3/$^{*}$3 genotype which is a poor metabolizer of CYP2C19$^{*}$3 was detected (p=0.078).Conclusion . These results suggest that the Tae-um type which is said to have high liver function in SCM has the tendency of high drug-metabolizing enzyme activity. With further study, the CYP polymorphism could serve as a scientific tool for SCM diagnosis.

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Objective Evaluation of Beamforming Techniques for Hearing Devices with Two-channel Microphone (2채널 마이크로폰을 이용한 청각 기기에서의 빔포밍에 대한 객관적 검증)

  • Cho, Kyeong-Won;Han, Jong-Hee;Hong, Sung-Hwa;Lee, Sang-Min;Kim, Dong-Wook;Kim, In-Young;Kim, Sun-I.
    • Journal of Biomedical Engineering Research
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    • v.32 no.3
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    • pp.198-206
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    • 2011
  • Hearing devices like cochlear implant, vibrant soundbridge, etc. try to offer better sound for people. In hearing devices, several beamformers including conventional directional microphone are applicable to noise reduction. Each beamformer has different directional response and it could change sound intelligibility or quality for listeners. Therefore, we investigated the performance of three beamformers, which are first and second order directional microphone, and broadband beamformer(BBF) with a computer simulation assuming hearing device microphone configuration. We also calculated objective measurements which have been used to evaluate speech enhancement algorithms. In the simulation, a single speech and a single babble noisewere propagated from the front and $135^{\circ}$ azimuth degrees respectively. Microphones were configured in an end-fire array and the spacing was varied in comparison. With 3 cm spacing, BBF had about 3 dB higher enhanced SNR than that of directional microphones. However, enhancement of segmental SNR and frequency weighted segmental SNR were similar between the first order directional microphone and broadband beamformer. In addition when steady state noise was used, broadband beamformer showed the increased performance and had the highest enhanced SNR, and segmental SNR.

A Study of Emergency Department Personnel's Job Satisfaction (응급실 근무 인력의 직무만족도에 대한 연구)

  • Lee, Jeong Heon;Shin, Im Hee
    • Quality Improvement in Health Care
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    • v.9 no.2
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    • pp.148-163
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    • 2002
  • Background : The personnel of emergency department have been under tremendous pressure to manage unexpected emergency situations and excited patients. And interpersonal conflict has existed always, because emergency department was consisted of various personnel of their own specialty. The patient's satisfaction has to come from the personnel's satisfaction. The purpose of this study was to evaluate emergency department personnel's job satisfaction and its related factors and to improve quality of emergency medical service Methods : A self-administered questionnaire survey to the emergency department personnel was conducted between September 1 and October 31, 2001. The response rate was 90.2%. Using SAS program (Version 6.12), the collected data was analyzed by frequency, ANOVA, multiple comparison, Pearson correlation procedure, and stepwise multiple regression analysis. Result : The analysis of related factors of job satisfaction showed high score of interpersonal interaction (3.246), professional prestige (3.095), autonomy (2.916), task requirements (2.701), organizational requirements (2.444), and pay (1.953) in order of item mean. Professional prestige (0.498), task requirements (0.464), and organizational requirements (0.408) were highly positive correlated with overall level of job satisfaction. The factors influencing the job satisfaction were professional prestige and task requirements which explaining efficacy were 37.6% and 32.2% respectively. The total explaining efficacy was 33.6%. Conclusion : It was found out that emergency department personnel's job satisfaction can be raised by promoting professional prestige and task requirements. The personnel of emergency department have to be satisfied through their job, and the administration of the hospital has to pay more attention to their employees' job satisfaction and it related factors.

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Development of the Wind Wave Damage Estimation Functions based on Annual Disaster Reports : Focused on the Western Coastal Zone (재해연보기반 풍랑피해예측함수 개발 : 서해연안지역)

  • Choo, Tai-Ho;Cho, Hyoun-Min;Shim, Sang-Bo;Park, Sang-Jin
    • The Journal of the Korea Contents Association
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    • v.18 no.1
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    • pp.154-163
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    • 2018
  • Not only South Korea but also Global world show that the frequency and damages of large-scale natural disaster due to the rise of heavy rain event and typhoon or hurricane intensity are increasing. Natural disasters such as typhoon, flood, heavy rain, strong wind, wind wave, tidal wave, tide, heavy snow, drought, earthquake, yellow dust and so on, are difficult to estimate the scale of damage and spot. Also, there are many difficulties to take action because natural disasters don't appear precursor phenomena However, if scale of damage can be estimated, damages would be mitigated through the initial damage action. In the present study, therefore, wind wave damage estimation functions for the western coastal zone are developed based on annual disaster reports which were published by the Ministry of Public Safety and Security. The wind wave damage estimation functions were distinguished by regional groups and facilities and NRMSE (Normalized Root Mean Square Error) was analyzed from 1.94% to 26.07%. The damage could be mitigated if scale of damage can be estimated through developed functions and the proper response is taken.