• Title/Summary/Keyword: frequency counting

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Content Analysis of the 5th grade Science Textbooks in Japan and Korea (한국과 일본 5학년 과학 교과서 내용 분석)

  • Kim, Hyo-Nam;Lee, Young-Mi
    • Journal of The Korean Association For Science Education
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    • v.15 no.4
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    • pp.452-458
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    • 1995
  • Science textbooks are very important materials in order to know elementary science learning in Japan and Korea. In this research the 5th grade science textbooks in Japan and Korea are analyzed by an analyzing category. The analyzing category is consisted of knowledge and scientific inquiry. Knowledge is divided by fact, concept, and rule. Scientific inquiry is divided by problem cognition, variable control, experiment planning, observing, measuring, categorizing, inferring, data transformation, predicting, correlation, cause and effect, result, communication, which are 13 subcategories. Analyzing methods are counting the frequency of each subcategory and tabulating the data. The results of this study are: 1. The frequency of scientific inquiry appeared in Korean 5th grade science textbooks is three times more than that in Japanese textbooks. 2. In scientific inquiry category, Japanese science textbooks emphasized observing, predicting, measuring and problem cognition; Korean science textbooks emphasized experiment planning, observing and problem cognition. 3. In knowledge category, fact subcategory is mostly emphasized in both countries.

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Frequency-Domain Properties of Digital Optimal stems Servosystem Counting Computation Delays (연산시간을 고려한 디지털 취적서보계의 주파수 특성)

  • 이동철;하주식
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.40 no.9
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    • pp.937-944
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    • 1991
  • In digital controller design, the delays in the controller should be taken into consideration when the computation time of the processor is not negligibale compared with sampling time. Recently, Mita has proposed a digital optimal servosystem taking account of the delays in the controller. In this paper, robust stability and diturbance rejection properties of this optimal servosystej are analyzed in the frequency-domain. The well-known asymptotic properties of the optimal regulators with respect to the weighting matrices of the cost functions are successfully utilized to show that the influence of the delays in the controller are drastic for certain choice of the cost function Illustrative numerical examples are presented.

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Current Driving Type Surge Counter (전류구동형 서지카운터)

  • Lee, B.H.;Ahn, C.H.;Chang, S.H.;Jeong, K.M.;Jeon, D.K.
    • Proceedings of the KIEE Conference
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    • 1997.07e
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    • pp.1712-1714
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    • 1997
  • This paper deals with the surge counter drived by lightning and switching currents. In order to install the effective surge protective devices, it is important to find the parameters of incident surges. In this paper, for the purpose of protecting the electronic circuits and counting the occuring frequency, the current driving type surge counter is designed and fabricated. The surge counter consists of surge protective divices, current detector, metal oxide varistor(MOV), rectifier, capacitor, and electromagnetic counter. This surge counter is able to count the occuring frequency of surges and to clamp lightning surge current. To evaluate the performance of the surge counter, impulse voltage and current were applied at the surge counter by the surge generator. As a result, applied surges were exactly counted and clamped.

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Relative Difficulty of Various English Writings by Fuzzy Reasoning and Its Application to Selecting Teaching Materials

  • Ban, Hiromi;Dederick, Toby;Nambo, Hidetaka;Oyabu, Takashi
    • Industrial Engineering and Management Systems
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    • v.3 no.1
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    • pp.85-91
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    • 2004
  • The writing styles of TIME and Newsweek are analyzed using a specially developed linguistic program. These two news magazines were chosen because of their wide popularity. As for the results, it became obvious that both the frequency curve of words and that of characters have not changed for the past 60 years. Also, we have found that the frequency curves have some inflection points and that the genre of English writings can be identified by these points. After counting the percentage of required vocabulary for junior high school students and high school students in English writings, we can derive the relative difficulties of them using fuzzy reasoning. Fuzzy rules are constructed using features of the characteristic curves. We feel it would be a good guide index when selecting textbooks or supplementary readers.

A Study on Development of Oscillator Measurement Device Using Double Edge Time Interval Frequency Counter (더블 에지타임 인터벌 카운터를 이용한 발진기특정 장치개발에 관한 연구)

  • Hwang, Gi-Hyun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.7
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    • pp.1386-1392
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    • 2009
  • In this paper, we have developed the test equipment to measure performance of oscillator using Double Side Edge Trigger(DSET). This DSET increases counting number of micro pulse by frequency counter, which will successfully reduce the half measuring time to comparison with the existing counter by using DSET. This new concept of performance measuring equipment provides a high productivity and performance improvement.

On Implementing the Digital DTMF Receiver Using PARCOR Analysis Method (PARCOR 분석 방법에 의한 디지털 DTMF 수신기 구현에 관한 연구)

  • Ha, Pan Bong;ANN, Souguil
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.24 no.2
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    • pp.196-200
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    • 1987
  • The following methods are proposed for implementing digital dual tone multi-frequency (DTMF) receiver: using infinite impulse response(IIR) digital filters, period-counting algorithm, discrete Fourier transform(DFT), and fast Fourier transform(FFT)[2]. The PARCOR(Partical Correlation) analysis method which has been widly used in the speech signal processing area is applied to the dual tone multi-frequency(DTMF) signal detection. This method is easy to implement digitally and stronger to digit simulation of speech than any other methods proposed up to date. Since sampling rate of 4KHz is used in the DTMF receiver for the detection of input DTMF signal originally sampled at 8KHz, it effects two times higher multiplexing efficiency.

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Mutant Frequency at the hprt Locus in Human T-Cell Exposed to Pentachlorophenol (Pentachlorophenol의 노출에 의한 사람 T-임파구의 hprt 유전자에서 돌연변이 빈도)

  • 윤병수;조명행;김인규;박선영;이영순
    • Toxicological Research
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    • v.13 no.1_2
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    • pp.71-78
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    • 1997
  • The mutational effects of pentachlorophenol (PCP) on the hypoxanthine phosphoribosyl transf erase (hprt) locus in human T-cell were analysed by T-cell clonal assay in vitro. Cells were exposed for 24 hours at primary culture to 0~100 ppm (W/V) PCP in dimethyl sulfoxide. Treated cells were allowed at the same time to stimulate by phytohemagglutinin (PHA) and T-cell growth factor (TCGF) and then seeded in medium containing 6-thioguanine to select for hprt-negative routants. We have also defined the optimal condition for the determination of mutant frequency. The parameters investigated include survival counting, first and second subculture for clonal efficiency plating and mutant plating. Under the optimal conditions, mutant frequencies of high dose-treated cells were significantly higher than those of non-treated or low dose cells. The results indicated a clear dose-effect relationship and showed that mutant frequency in 50 ppm PCP treated cell was 4.31$\times$$10^{-5}$ (background, 8.32$\times$$10^{-6}$). Above data strongly suggest that hprt mutation assay can be used as a biomarker for the environmental risk assessment.

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High-speed, High-resolution Phase Measuring Technique for Heterodyne Displacement Measuring Interferometers (헤테로다인 변위 측정 간섭계의 고속, 고분해능 위상 측정)

  • Kim, Min-Seok;Kim, Seung-Woo
    • Journal of the Korean Society for Precision Engineering
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    • v.19 no.9
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    • pp.172-178
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    • 2002
  • One of the ever-increasing demands on the performances of heterodyne interferometers is to improve the measurement resolution, of which current state -of-the-art reaches the region of sub-nanometers. So far, the demand has been met by increasing the clock speed that drives the electronics involved fur the phase measurement of the Doppler shift, but its further advance is being hampered by the technological limit of modem electronics. To cope with the problem, in this investigation, we propose a new scheme of phase -measuring electronics that reduces the measurement resolution without further increase in clock speed. Our scheme adopts a super-heterodyne technique that lowers the original beat frequency to a level of 1 MHz by mixing it with a stable reference signal generated from a special phase- locked-loop. The technique enables us to measure the phase of Doppler shift with a resolution of 1.58 nanometer at a sampling rate of 1 MHz. To avoid the undesirable decrease in the maximum measurable speed caused by the lowered beat frequency, a special form of frequency up-down counting technique is combined with the super-heterodyning. This allows performing required phase unwrapping simply by using programmable digital gates without 2n ambiguities up to the maximum velocity guaranteed by the original beat frequency.

A Study on the Quantity Food Production Practices of Foodservice in Sangju and Near-by Region (상주 및 인근지역 단체급식소의 다량조리 실태 연구 -식단분석 및 다량조리 실태-)

  • 박모라;김귀영;박필숙;강우원
    • Journal of the East Asian Society of Dietary Life
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    • v.8 no.1
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    • pp.36-50
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    • 1998
  • The purpose of this study was to investigate quantity food production practices in foodservices by analysing the menus of April, 1996, The questionnaire was developed and responded to by 96 dietitians in Sangju, Munkyung, Gumee, Kimchun, and Andong during November, 1996. The survey was performed by simple random samplings. The results were as follosw; 1. Hospitals and industry served food for thirty days and schools for twenty days. Kimchi was a select-menu for hospitals and one side dish for industry and schools. The type of menu was a single use menu which consisted of cooked rice, soups and three side dishes. 2. The most frequently used ingredients were green onions, rice, carrots, onions, Korean radish roots, pork, eggs, glutinous rice, and milk. Kimchis were served most frequently in all food services and cooked rices and soups were next. 3. The age of most of the respondents was 26 to 30.54.2% of subjects were juniou college graduates and 77.1% were single. Fifty seven point three percent of the dietitians lived with family relatives, or friends. 87.5% of the dietitians had been working for 1 to 5 years. 4. Most foodservices were self-operated. The number of meals served was determined by meal coupon counting in hospitals(37.5%), meal board counting in industry(29.2%), and attendance card counting in schools(41.1%) The cost of sales per meal was approximately 2,450 won in hospitals and was approximately 1,100 won in industry and schools. The average number of days per menucycle was 7.4 in hospitals. 10.3 in industry and 25.5 in schools. Hospitals, industry, and schools held about 118, 265 and 263 recipes respectively. The average number of dietitians was 2.6 in hospitals and 1.0 in industry and schools. Except for the number of recipes, the general practices of foodservices were significantly different(P<0.05). 5. In the general quantity food production, food and seasonings measuring was hardly done. the percentage of foodservices using chemical seasonings was higher in hospitals and industry than in schools. the most important concern was taste, Registered cooks were employed in 75% of schools but only 50.0% in hospitals and 20.8% in industry. Most of the dietitians respinded that their cooks skill was not bad. The education of unregistered cooks was performen once or two times a month in hospitals and industry, and in schools performed everyday. The problem when educating cooks was the lack of cooking skill of the dietitians in schools, and the lack of time in hospitals, and the negative attitude toward education in industry. The method for improving cooking in all foodservices was OJT, or the extension of education facilities and the development and dissemination of standard recipes. The frequency of throwing away leftovers was higher in hospitals. But in industry, the frequency of saving leftovers was higher. 6. Though all foodservices have standard recipes, the number that used them was low, Another problem is that standard recipes resulted in leftovers. The inconveniences of using standard recipes were the difficulty of applying standard recipes to various numbers of customers the complication of use, or facility insufficiency.

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The Study for Apical Pulse Measurement Technique Through Hospitalized Children (입원한 영유아의 심첨 맥박 측정 방법에 관한 연구)

  • Cho Kyung Mi;Kim Eun Joo
    • Child Health Nursing Research
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    • v.5 no.1
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    • pp.48-58
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    • 1999
  • The purpose of this study was to determine the most accurate technique measuring the apical pulse rate, using three counting duration 15, 30 and 60 seconds, and two methods start ‘0’ and start ‘1’. The instrument used in the study was the EKG monitor, stethoscope and stopwatch. Data was analyzed by utilizing SPSSWIN program. General characteristics of the subjects were analyzed by frequency, percentile, mean, SD. The subject of this research is made up of 46 children and 20 nurses. The children were infants, & under the age of 5. They were hospitalised in PICU & NICU in 2 tertiary hospitals in seoul from Jan. 1. 1998 to Sep. 10. 1998. The measurement of starting 1 & measurement of starting ‘0’ used the T-test to find out the measurement error. Apical pulse duration of 15, 30, 60 seconds were used to find out measurement error, the measurement error depend on experience of Nurse were analyzed by using ANOVA. The result of this study are as follows. 1. When comparing the starting poin of apical pulse 0&1, starting with 1 the measurement error is less, but not statiscally significant. 2. When counting the apical pulse by 15, 30,60 sec. ; 60 seconds counting duration was more accurate, but not statistically significant. 3. The mean of measure error ; Group under 100/min, is 10.33 ; from 100 re 119/min, is 8.30 ; from 120 to 139/min, is 4.76 ; from 140 to 159/min, is 6.09 ; above 160, is 17.83. The differences of these groups are statistically significant. When 60sec were counted, under 140/min the mean of measurement error is 3.4. Also when 30 seconds were counted from 140/min to 159/min the measurement error is 7.14, above 160/min the measurement error is 16.4. That measurement mean is the smallest than the other durations. During the 15 sec. count the measurement error was the largest of them all. 4. By the experience of the nurses, the apical pulse count measurement error was discovered. Under a year experience this measurement error was the largest(11.09), 1 year to under 3 years, the error is the smallest(4.86). 3 year to under 6 years the error is 8.33, 5 years above the error is 6.11 but this is not statistical significant. Under a year experience when counting 15, 30, 60 seconds the error is the largest. The group of the nurses from a year to under 3 years, the measurement error is the smallest of all the groups. The result of the study is to determine the technique measuring the apical pulse rate, Hargest (1974), starting point ‘0’ is not proved. When the pulse rate increases the 30 sec measurement rate is accurate. Under 140/min the 60 sec measurement rate is the most accurate. Depending on the nurses experiences, there is a variable difference to the apical pulse rate measurement. Especially new nurses training courses should enforce the children’s pulse rate count and the basic vital signs.

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