• Title/Summary/Keyword: frequency-response

Search Result 5,567, Processing Time 0.035 seconds

A Study on Curriculum of Dental Hygienists (치과위생사 교육과정 연구)

  • Park, II-Soon
    • Journal of Korean society of Dental Hygiene
    • /
    • v.4 no.2
    • /
    • pp.193-207
    • /
    • 2004
  • The aims of the study are as following : First, define and clarify the role and function of the dental hygienist. Second, based on thai definition, present an improved dental hygienist curriculum, improving their special competence. This study seeks to present a way for promoting role of dental hygienists as independent specialists, rather than as auxiliaries, contributing to better dental service in the process. The research was pursued by surveying by questionnaire those directly related to dental hygiene. They are 58 professors of dental hygiene, 164 dentists, 253 dental hygienists and 496 dental hygiene students, selected by the method of simple random sampling. Due to the small size of the sample, professors' group was analysed only through frequency and probabilities. For groups with larger samples(dentists, dental hygienists, dental hygiene students), methods of chi square(${\chi}^2$) tests, frequency analysis and one-way ANOVA were used in their analysis. Conclusions of the study are as following : First, role and function of the dental hygienist was defined and clarified. According to the analysis of the survey, main role of the dental hygienists as perceived by 62.9% of dentists was supporting treatments and managing patients and facility. This perception by dentists differs significantly to perception of other groups, which saw main role of dental hygienists as preventive dental treatment and dental hygiene education. Also, only 20.2% of dental hygienists perceived patients and facility management as their main role. This divergence of perception between groups weakens speciality competence of dental hygienists. To strengthen dental hygienists' speciality competence, preventive dental treatment and dental hygiene education must be defined as main role of dental hygienists. Furthermore, role of dental hygienists can be categorized into cooperative and auxiliary role. Second, in order to strengthen speciality competence of dental hygienists, their education must be augmented with curriculum emphasizing cooperative role. Specifically, courses on preventive dental treatment, dental hygiene education and dental X-ray photography must become compulsory, as well as becoming more comprehensive and organized. Also, training in schools and hospitals must be focused on those subjects. In addition, courses concerning auxiliary role must be incorporated into optional courses and more pedagogical courses are needed to widen students' career choices. Third, practical relevance of national dental hygienist certification examination must be heightened. In the survey, all groups gave negative response to questions concerning practical relevance of national dental hygienist certification test. Specifically, contents of the tests must be changed to test participants' competence in the cooperative area. Also, the test itself must be strengthened by adding practical examination to the certification scheme, as well as having more difficult examinations.

  • PDF

The Effect of Acupuncture on the Intestinal Smooth Muscle Dysfunction Caused by Enteric Bacterial Infection in Weaning Piglet (돼지의 세균성 위장관 질환에 따른 평활근 기능 이상에 대한 침술의 효과)

  • Kim, Tae-wan;La, Jun-ho;Sung, Tae-sik;Kang, Jeong-woo;Nam, Tchi-chou;Choi, Min-cheol;Yoon, Yeo-sung;Yang, Il-suk
    • Korean Journal of Veterinary Research
    • /
    • v.43 no.3
    • /
    • pp.415-421
    • /
    • 2003
  • It is now generally accepted that acupuncture is effective in diarrhea caused by bacterial infection. However, its effect on the intestinal smooth muscle dysfunction is not clear. Therefore, we investigated the effect of acupuncture therapy at Jiao-chao (GV-1) on the intestinal muscle dysfunction in weaning piglets orally infected by Escherichia coli. The animals are divided into four groups; 1) E. coli + no-treatment, 2) E. coli + antibiotic, 3) E. coli + acupuncture, 4) normal group. In the three E. coli infected groups, low frequency electrical field stimulation (EFS, 1 Hz) provoked triphasic responses composed of initial relaxation followed by on-contraction and off-contraction. While in the normal group, EFS (1Hz) induced biphasic responses composed of relaxation during the stimulation and off-contraction. At the high frequency (16Hz) EFS, both on-contraction and off-contraction of the E. coli + antibiotic, E. coli + acupuncture and the normal group were larger than those of the E. coli + no-treatment group. In the non-adrenergic non-cholinergic (NANC) condition, only biphasic responses occurred to EFS in all experimental groups and the off-contraction of E. coli + antibiotic, E. coli + acupuncture and the normal group were larger than those of the E. coli + no-treatment group. The response to carbachol of those three groups was also significantly greater than that of the E. coli + no-treatment group. These results suggest that acupuncture is as effective as antibiotic in the dysfunction of colonic circular muscle caused by E. coli infection. The maintenance of contractile neuromuscular transmission seems to be involved in the mechanism of the acupuncture effects on diarrhea.

Does the Bush Warbler (Cettia diphone) Defend Its Territory through a Particular Song Mode or a Mode Sequence? (텃새권 방어와 관련된 휘파람새의 Song Mode와 Mode Sequence의 이용)

  • 박대식;박시룡
    • The Korean Journal of Zoology
    • /
    • v.39 no.3
    • /
    • pp.282-291
    • /
    • 1996
  • The song of the bush warbler, Cettia diphone, consists of an introdudory whisde portion and a complex ending syllable portion. In bush warbiers, a song with two or fewer notes in the whistle portion is classified as an a song mode, while a song with three or more notes in the whistle portion as a $\beta$ song mode. Although some variations occur in mode seledion by individuals and populations, the proportion of a mode songs to total songs is 55% (range 51.6-58.7%) on average. The a mode has a higher dominant frequency in the whistle portion than does the $\beta$ mode, but the number of syllables m the complex ending syllable portion is fewer. Bush warbler mode sequences are defined as $\alpha$$\alpha$, $\alpha$$\beta$, $\beta$$\alpha$ and $\beta$$\beta$ mode sequences. In order to test the hypothesis that song modes and mode sequences play a role in the defence of territory in Jeju and Wando populations in the south-coastal geographic song variation group, playback experiments were executed. Mode sequences differed between naturally produced songs and songs produced in response to playback for two populations. In particular, for birds in the Wando populations our results indicate that the use of song modes may be affeded by habitat, singing site and type of territory, and further propose that particular mode sequences may play a more important role than song mode in vocal interadions.

  • PDF

Investigation of Sound Pressure Detection of Fiber Optic Sensor in Transformer Oil According to TLS and CW Laser Source (TLS와 CW 광원에 따른 트랜스포머 오일 내에서 광섬유 센서의 음압 감지 특성 연구)

  • Lee, Jong-Kil
    • The Journal of the Acoustical Society of Korea
    • /
    • v.30 no.1
    • /
    • pp.33-41
    • /
    • 2011
  • To substitute TLS in the hybrid system which is combined with Sagnac interferometer and fiber bragg grating (FBG) it is necessary to investigate how the laser source (TLS and CW) and sensor material variate the response of fiber optic sensor. Two different hollow cylinder type mandrel materials are proposed which are PTFE and PTFE+carbon and 18 m optical fiber is wounded at the mandrel surface. CW laser source experiments had been done in the oil tank which is filled with transformer oil in the 1 kHz~20 kHz frequency range. Also Sagnac interferometer fiber optic sensor is combined with FBG called hybrid system and TLS used as a light source. Based on the experimental results PTFE sensor showed more higher magnitude of detection signal rather than carbon sensor and this result is agreement with the McMahon's theoretical results. Phase variation is inversely proportional to the elastic modulus of the mandrel material. In PTFE fiber sensor, tunable laser source showed more higher performance rather than CW case. Therefore, TLS fiber optic sensor can be applied to the hybrid system which is combined with Sagnac and FBG.

Estimation of Dynamic Displacement and Characteristics of A Simple Beam from FBG Sensor Signals (FBG센서 응답을 이용한 단순보의 동적 변위 및 동특성 추정)

  • Choi, Eun Soo;Kang, Dong Hoon;Chung, Won Seok;Kim, Hak Soo
    • Journal of Korean Society of Steel Construction
    • /
    • v.18 no.4
    • /
    • pp.503-514
    • /
    • 2006
  • FBG sensors are capable of measuring the strain of structures easily and more durably than electric resistance gauges. Thus, many researches are dedicated to the application for the response monitoring or non-destructive evaluation of structures using FBG sensors. Additionally, the measured strains at the top and bottom of a cross-section can be transformed into the curvature of the section, which can be used to calculate its vertical displacement. Hence, this study aims to measure the dynamic strain signals of a steel section simply supported beam and to estimate the dynamic displacement from the strain signals, after which the estimated displacement is com pared with the measured displacement. The dynamic characteristics (natural frequency, damping ratio and mode shape) of the beam are predicted from both the estimated and measured displacement signals, and from the strain time history of the FBG sensors. The predicted properties are compared with those of an analytical model of the beam. The estimated displacement. However, the predicted dynamic properties from both the estimated displacements and the measured strains are well-correlated with those from the measured displacement. It is therefore appreciated that the estimation of the dynamic properties of FBG sensor signals is reasonable. Especially, the strain signal of the FBG sensor was amplified at a higher-frequency region in comparison with the displacement estimation with higher-mode properties.

Satellite finite element model updating for the prediction of the effect of micro-vibration (미소진동 영향성 예측을 위한 인공위성 유한요소모델 보정)

  • Lim, Jae Hyuk;Eun, Hee-Kwang;Kim, Dae-Kwan;Kim, Hong-Bae;Kim, Sung-Hoon
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.42 no.8
    • /
    • pp.692-700
    • /
    • 2014
  • In this work, satellite FE (finite element) model updating for the prediction of the effect of micro-vibration is described. In the case of satellites launched in low earth orbit, high agility and more mission accomplishments are required by the customer in order to procure many images from satellites. To achieve the goal, many mechanisms, including high capacity wheels and antennas with multi-axis gimbals have been widely adopted, but they become a source of micro-vibration which could significantly deteriorate the quality of images. To investigate the effect due to the micro-vibration in orbit on the ground, a prediction is conducted through an integrated model coupling the measured jitter sources with FE (finite element) model. Before prediction, the FE model is updated to match simulation results with the modal survey test. Subsequently, the quality of FE model is evaluated in terms of frequency deviation error, the resemblance of mode shapes and FRFs (frequency response functions) between test and analysis.

Safety Oimate Practice and its Affecting Variables in the Chemical Process Industry (화학공정산업에서 안전문화 이행과 영향 변수)

  • Baek, Jong-Bae
    • Journal of the Korean Society of Safety
    • /
    • v.21 no.4 s.76
    • /
    • pp.127-133
    • /
    • 2006
  • The major purpose of this paper to identify safety climate practices, and to find the affecting variables that influence to the difference in the level of safety climate between plants and employees. And this paper attempted to find the interventions for improving safety climate in the chemical plants. The questionnaires were developed from literature review, especially made by HSE(Health and Safety Executive) in the UK and distributed to managers and workers. The frequency analysis was applied for identifying the level of safety climate. The affecting variables(plant size, accident occurrence, accident experience, injury experience and severity, and length of employment) are tested through analysis of variance(ANOVA). The results of frequency analysis showed that both managers and workers recorded generally high level of safety climate, and the major underlying problems are inadequate H&S procedures/rules, pressure for production, and rule breaking. According to the outcomes of ANOVA, the variable 'length of employment' is the only variable which makes the level of safety climate different. From the survey of safety climate practice, this study finds the level of safety climate and three major underlying problems in safety climate factors of the responded plants, and presents two interventions for improving safety performance. Despite of these outcomes, the applied factors are remained questionable for reflecting as the best ones for identifying safety climate in the chemical industry. In addition, the bias caused by self-report exist in the reliability of the response, and the equivalent size of respondents.

The Effects of Verbal Violence in Clinical Practice, Academic Stress Coping, and Depression on Professional Self-concepts among Korean Nursing Students (간호대학생의 임상실습 시 경험한 언어폭력, 학업스트레스 대처 및 우울이 전문직 자아개념에 미치는 영향)

  • Jeon, Hae Ok
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.19 no.8
    • /
    • pp.501-512
    • /
    • 2018
  • The aims of this study were to investigate the effects of verbal violence experienced during clinical practice, emotional responses, academic stress coping, and depression on professional self-concepts of nursing students. Data were collected through a self-reported structured questionnaire form given to nursing students in grades 3-4 using convenient sampling methods from October 25 to November 1, 2017. As a result, 41.9% of the subjects experienced verbal violence during clinical practice. The frequency of experiences for verbal violence was '1 time' at 16.9%, '2 times' at 15.5%, and '3 times' at 4.7%. The verbal violence attackers were patients (42.9%), nurses (37.7%), and protector (15.5%). Emotional response was positively correlated with depression and frequency of verbal violence. Academic stress coping had a negative correlation with depression and a positive correlation with professional self-concept. Depression was negatively correlated with professional self-concept. Multiple regression analysis showed that academic stress coping and depression were statistically significant variables in the professional self-concept, and these variables had a 28% explanatory power. Therefore, in order to improve the professional self-concept of nursing students, it is necessary to develop a strategy to raise the level of academic stress coping and to reduce depression.

Analyzing of CDTA using a New Small Signal Equivalent Circuit and Application of LP Filters (새로운 소신호 등가회로를 활용한 CDTA의 해석 및 저역통과 필터설계)

  • Bang, Junho;Song, Je-Ho;Lee, Woo-Choun
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.15 no.12
    • /
    • pp.7287-7291
    • /
    • 2014
  • A CDTA (current differencing transconductance amplifier) is an active building block for current mode analog signal processing with the advantages of high linearity and a wide frequency bandwidth. In addition, it can generate a stable voltage because all the differencing input current flows to the grounded devices. In this paper, a new small signal equivalent circuit is proposed to analyze a CDTA. The proposed small signal equivalent circuit provides greater precision in analyzing the magnitude and frequency response than its previous counterparts because it considers the parasitic components of the input, internal and output terminal. In addition, observations of the changes made in various devices, such as the resistor (Rz) confirmed that those devices heavily influence the characteristics of CDTA. The designed parameters of the proposed small signal equivalent circuit of the CDTA provides convenience and accuracy in the further design of analog integrated circuits. For verification purposes, a 2.5 MHz low pass filter was designed on the HSPICE simulation program using the proposed small signal equivalent circuit of CDTA.

Spatial and Temporal Characteristics of Summer Extreme Precipitation Events in the Republic of Korea, 2002~2011 (우리나라 여름철 극한강수현상의 시·공간적 특성(2002~2011년))

  • Lee, Seung-Wook;Choi, Gwangyong;Kim, Baek-Jo
    • Journal of the Korean association of regional geographers
    • /
    • v.20 no.4
    • /
    • pp.393-408
    • /
    • 2014
  • In this study, the spatio-temporal characteristics of summer extreme precipitation events in the Republic of Korea are examined based on the daily precipitation data observed at approximately 360 sites of both Automatic Weather Station (AWS) and Automated Synoptic Observation System (ASOS) networks by the Korea Meteorological Administration for the recent decade(2002~2011). During the summer Changma period(late June~mid July), both the frequency of extreme precipitation events exceeding 80mm of daily precipitation and their decadal maximum values are greatest at most of weather stations. In contrast, during the Changma pause period (late July~early August), these patterns are observed only in the northern regions of Geyeonggi province and western Kangwon province as such patterns are detected around Mt. Sobaek and Mt. Halla as well as in the southern regions of Geyeonggi province and western Kangwon province during the late Changma period (mid August~early September) due to north-south oscillation of the Changma front. Investigation of their regional patterns confirms that not only migration of the Changma front but also topological components in response to the advection of moistures such as elevation and aspect of major mountain ridges are detrimental to spatio-temporal patterns of extreme precipitation events. These results indicate that each local administration needs differentiated strategies to mitigate the potential damages by extreme precipitation events due to the spatiotemporal heterogeneity of their frequency and intensity during each Changma period.

  • PDF