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Stochastic Analysis in the Generation of Floor Response Spectra for Liner Systems with Proportional Damping (추계학적(推計學的) 해석법(解析法)에 의한 선형비례감쇠(線形比例減衰) 시스템의 층응답(層應答)스펙트럼)

  • Park, Young Suk;Seo, Jeong Moon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.8 no.1
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    • pp.77-85
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    • 1988
  • A stochchastic analysis procedure of generating floor response spectra for proportionally damped linear systems subject to earthquake loading is presented. Theories of random vibration and mode acceleration method are used in the formulation of governing equations. The structure-oscillator interaction is not considered. It is assumed that the input motions and oscillator responses are stationary Gaussian processes with mean zero. The nonstationary characteristics of earthquake motion are incorporated in the peak factor which is based on Vanmarcke's theory. Floor response spectra for both resonance and non-resonance cases are calculated under the assumption that the peak factors for structure and oscillator are equal to that for ground response spectrum. The validity of this method is demonstrated by comparing the results obtained by proposed method with those by time history analyses. The results obtained by this method are conservative and accurate with tolerable precision. This method saves much computing time compared with time history analysis method.

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Outcomes into Adulthood of Survivors Born Either Extremely Low Birthweight or Extremely Preterm

  • Doyle, Lex W
    • Neonatal Medicine
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    • v.25 no.1
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    • pp.7-15
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    • 2018
  • We need to understand the outcomes into adulthood for survivors born either extremely low birthweight (ELBW; <1,000 g) or extremely preterm (EP; <28 weeks' gestational age), particularly their blood pressure and cardiovascular metabolic status,respiratory function, growth, psychological and mental health performance, and functional outcomes. Blood pressure is higher in late adolescence and early adulthood in ELBW/EP survivors compared with controls. In some studies, expreterm survivors have higher insulin and blood lipid concentrations than controls, which may also increase their risk for later cardiovascular disease. ELBW/EP survivors have more expiratory airflow obstruction than do controls. Those who had bronchopulmonary dysplasia (BPD) in the newborn period have even worse lung function than those who did not have BPD. As a group, they are unlikely to achieve their full lung growth potential, which means that more of them are likely to develop chronic obstructive airway disease in later life. Although they are smaller than term born controls, their weight gradually rises and ultimately reaches a mean z-score close to zero in late adolescence, and they ultimately attain a height z-score close to their mid-parental height z-score. On average, ex-preterm survivors have intelligence quotient (IQ) scores and performance on tests of academic achievement approximately 2/3 SD lower than do controls, and they also perform less well on tests of attention and executive function. They have similar high rates of anxiety and depression symptoms in late adolescence as do controls. They are, however, over-represented in population registries for rarer disorders such as schizophrenia and Autism Spectrum Disorder. In cohort studies, ex-preterm survivors mostly report good quality of life and participation in daily activities, and they report good levels of self-esteem. In population studies, they require higher levels of economic assistance, such as disability pensions, they do not achieve education levels as high as controls, fewer are married, and their rates of reproduction are lower, at least in early adulthood. Survivors born ELBW/EP will present more and more to health carers in adulthood, as they survive in larger numbers.

Genetic parameters for daily milk somatic cell score and relationships with yield traits of primiparous Holstein cattle in Iran

  • Kheirabadi, Khabat;Razmkabir, Mohammad
    • Journal of Animal Science and Technology
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    • v.58 no.10
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    • pp.38.1-38.6
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    • 2016
  • Background: Despite the importance of relationships between somatic cell score (SCS) and currently selected traits (milk, fat and protein yield) of Holstein cows, there was a lack of comprehensive literature for it in Iran. Therefore we tried to examine heritabilities and relationships between these traits using a fixed-regression animal model and Bayesian inference. The data set consisted of 1,078,966 test-day observations from 146,765 primiparous daughters of 1930 sires, with calvings from 2002 to 2013. Results: Marginal posterior means of heritability estimates for SCS ($0.03{\pm}0.002$) were distinctly lower than those for milk ($0.204{\pm}0.006$), fat ($0.096{\pm}0.004$) and protein ($0.147{\pm}0.005$) yields. In the case of phenotypic correlations, the relationships between production and SCS were near zero at the beginning of lactation but become increasingly negative as days in milk increased. Although all environmental correlations between production and SCS were negative ($-0.177{\pm}0.007$, $-0.165{\pm}0.008$ and $-0.152{\pm}0.007$ between SCS and milk, fat, and protein yield, respectively), slightly antagonistic genetic correlations were found; with posterior mean of relationships ranging from $0.01{\pm}0.039$ to $0.11{\pm}0.036$. This genetic opposition was distinctly higher for protein than for fat. Conclusion: Although small, the positive genetic correlations suggest some genetic antagonism between desired increased milk production and reduced SCS (i.e., single-trait selection for increased milk production will also increase SCS).

Research on the Ground Water Developement in the Region of Choong Nam Province (충남지역의 지하수개발에 관한 조사)

  • 민병섭
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.11 no.4
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    • pp.1827-1831
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    • 1969
  • Resulties of research on the capacity of ground water of 994 concrete-pipe-wells and 97 infiltration-gallerys in ground-water-developement-works region executed from March to Julyin 1969, in Choong Chung Nam Do, and research on the quality of ground water for 88 wells for home-use around of River Geum Area, are as fellows: (1) Thickness of aquifer is no more than 2.85m averagely even at river-overflowed plain, alluvial plain and valley plain area that are estimated to contain ground water mostly. And so, it is guessed that ground water capacity is not much especially. (2) Soil of aquifer of the above area is sand or gravel and it is estimated to be good for ground water developement and its mean permeability coefficient is bout $2.5{\times}10^{-3}$(m/sec), and its porosity is about 33.9%. (3) The quality of ground water is good for irrigation water exception of delta plain area. Warm water plan is to need for irrigation water when water temperature is less than 19 degrees below zero. (4) Prospect of ground water developement, judging from quality and quantity, expects to lay infiltration gallery under the ground at river bed in order to utilize under-flow-water of river bed, river-overflowed plain, alluvial plain and valley plain that ground level is less than 50m. (5) Collectable water volume of under-flow-water of river bed is about 450 to $750m^3/day$ to be able to irrigate 3ha to 5ha of the cultivated land in case that infiltration gallery length is 50m and its depth is about 5m. (6) Collectable water volume at river-overflowed plain, alluvial plain and valley plain area, is estimated $150m^3/day$ to be able to irrigated 1ha of the cultivated land.

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Dose-related Effects of Follicle Stimulating Hormone on Superovulation in Indigenous Cows of Bangladesh

  • Hossein, M.S.;Shamsuddin, M.;Bhuiyan, M.M.U.;Khan, A.H.M.S.I.;Bari, F.Y.
    • Journal of Embryo Transfer
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    • v.17 no.2
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    • pp.123-128
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    • 2002
  • The present study aimed at determining the effective dose of Folltropin, a follicle timulating hormone (FSH), on superovulation in indigenous cows of Bangladesh. Fifteen regularly cycling 5~7 years old dry cows, weighing 200~250 kg with 2.5~3.0 body condition scores (BCS) were divided into three groups (n=5). Individual groups were superovulated with 100, 200 or 300 mg of Folltropin per animal. The superovulation treatment was initiated at Day 10 or Day 11 of the estrous cycle (Day 0=day of estrus). Alfaprostol (6 mg) was injected to each cow 72 h after the initiation of superovulation treatment to induce eestrus. After confirming standing estrus, the cows were inseminated 2~3 times, 12 h apart, depending on the duration of estrus. At Day 6 or Day 7, individual horns of the uterus were flushed with 150~200 $m\ell$ of phosphate buffered saline supplemented with BSA (0.2%), penicillin (100 IU/$m\ell$) and streptomycin (100 $\mu\textrm{g}$$m\ell$) using a two-way foley catheter. The embryos were concentrated, removing the excess medium through an embryo filter, and identified under a stereomicroscope. The identified embryos were collected, washed four times, evaluated and graded as excellent, good, fair or poor. The excellent, good and fair embryos were considered as transferable quality embryos. The mean (range). numbers of embryos collected vs. transferable quality embryos far 100, 200 and 300 mg of Folltropin were 4.5 (1~10) vs. 3.5 (1~8); 2.5 (1~4) vs. 1 (0~2) and 0.0 (0~0) vs. 0.0 (0~0), respectively, Folltropin at a dose of 100 or 200 mg produced suitable ovarian stimulation for superovulation in indigenous zebu cows of Bangladesh. A dose of 300 mg or more Folltropin consistently caused preovulatory corpora lutea formation in the ovaries and resulted in zero embryo recovery.

Prediction of Dormancy Release and Bud Burst in Korean Grapevine Cultivars Using Daily Temperature Data (기온자료에 근거한 주요 포도품종의 휴면해제 및 발아시기 추정)

  • Kwon Eun-Young;Song Gi-Cheol;Yun Jin I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.7 no.3
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    • pp.185-191
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    • 2005
  • An accurate prediction of dormancy release and bud burst in temperate zone fruit trees is indispensable for farmers to plan heating time under partially controlled environments as well as to reduce the risk of frost damage in open fields. A thermal time-based two-step phenological model that originated in Italy was applied to two important grapevine cultivars in Korea for predicting bud-burst dates. The model consists of two sequential periods: a rest period described by chilling requirement and a forcing period described by heating requirement. It requires daily maximum and minimum temperature as an input and calculates daily chill units (chill days in negative sign) until a pre-determined chilling requirement for rest release is met. After the projected rest release date, it adds daily heat units (anti-chill days in positive sign) to the chilling requirement. The date when the sum reaches zero isregarded as the bud-burst in the model. Controlled environment experiments using field sampled twigs of 'Campbell Early' and 'Kyoho' cultivars were carried out in the vineyard at the National Horticultural Research Institute (NHRI) in Suwon during 2004-2005 to derive the model parameters: threshold temperature for chilling and chilling requirement for breaking dormancy. The model adjusted with the selected parameters was applied to the 1994-2004 daily temperature data obtained from the automated weather station in the NHRI vineyard to estimate bud burst dates of two cultivars and the results were compared with the observed data. The model showed a consistently good performance in predicting the bud burst of 'Campbell Early' and 'Kyoho' cultivars with 2.6 and 2.5 days of root mean squared error, respectively.

Nonlinear Vibration Analyses of Stiffened Composite Panels under Combined Thermal and Random Acoustic Loads (열-랜덤 음향 하중을 받는 보강된 복합재 패널의 비선형 진동 해석)

  • Choi, In-Jun;Lee, Hong-Beom;Park, Jae-Sang;Kim, In-Gul
    • Journal of the Korea Institute of Military Science and Technology
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    • v.23 no.6
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    • pp.533-541
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    • 2020
  • This study using ABAQUS investigates the nonlinear vibration responses when thermal and random acoustic loads are applied simultaneously to the stiffened composite panels. The nonlinear vibration analyses are performed with changing the number of stiffeners, and layup condition of the skin panel. The panel and stiffeners both are modeled using shell elements. Thermal load (ΔT) is assumed to have the temperature gradient through the thickness direction of the stiffened composite panel. The random acoustic load is represented as stationary white-Gaussian random pressure with zero mean and uniform magnitude over the panels. The thermal postbuckling analysis is conducted using RIKS method, and the nonlinear dynamic analysis is performed using Hilber-HughesTaylor time integration method. When ΔT = 25.18 ℃ and SPL = 105 dB are applied to the stiffened composite panel, the effect of the number of stiffener is investigated, and the snap-through responses are observed for composite panels without stiffeners and with 1 and 3 stiffeners. For investigation of the effect of layup condition of the skin panel, when ΔT = 38.53 ℃ and SPL = 110 dB are applied to the stiffened composite panel, the snap-through responses are shown when the fiber angle of the skin panel is 0°, 30°, and 60°.

Optical Character Recognition for Hindi Language Using a Neural-network Approach

  • Yadav, Divakar;Sanchez-Cuadrado, Sonia;Morato, Jorge
    • Journal of Information Processing Systems
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    • v.9 no.1
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    • pp.117-140
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    • 2013
  • Hindi is the most widely spoken language in India, with more than 300 million speakers. As there is no separation between the characters of texts written in Hindi as there is in English, the Optical Character Recognition (OCR) systems developed for the Hindi language carry a very poor recognition rate. In this paper we propose an OCR for printed Hindi text in Devanagari script, using Artificial Neural Network (ANN), which improves its efficiency. One of the major reasons for the poor recognition rate is error in character segmentation. The presence of touching characters in the scanned documents further complicates the segmentation process, creating a major problem when designing an effective character segmentation technique. Preprocessing, character segmentation, feature extraction, and finally, classification and recognition are the major steps which are followed by a general OCR. The preprocessing tasks considered in the paper are conversion of gray scaled images to binary images, image rectification, and segmentation of the document's textual contents into paragraphs, lines, words, and then at the level of basic symbols. The basic symbols, obtained as the fundamental unit from the segmentation process, are recognized by the neural classifier. In this work, three feature extraction techniques-: histogram of projection based on mean distance, histogram of projection based on pixel value, and vertical zero crossing, have been used to improve the rate of recognition. These feature extraction techniques are powerful enough to extract features of even distorted characters/symbols. For development of the neural classifier, a back-propagation neural network with two hidden layers is used. The classifier is trained and tested for printed Hindi texts. A performance of approximately 90% correct recognition rate is achieved.

Design, Fabricaiton and Testing of a Piezoresistive Cantilever-Beam Microaccelerometer for Automotive Airbag Applications (에어백용 압저항형 외팔보 미소 가속도계의 설계, 제작 및 시험)

  • Ko, Jong-Soo;Cho, Young-Ho;Kwak, Byung-Man;Park, Kwan-Hum
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.2
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    • pp.408-413
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    • 1996
  • A self-diagnostic, air-damped, piezoresitive, cantilever-beam microaccelerometer has been designed, fabricated and tested for applications to automotive electronic airbag systems. A skew-symmetric proof-mass has been designed for self-diagnostic capability and zero transverse sensitivity. Two kinds of multi-step anisotropic etching processes are developed for beam thickness control and fillet-rounding formation, UV-curing paste has been used for sillicon-to-glass bounding. The resonant frequency of 2.07kHz has been measured from the fabricated devices. The sensitivity of 195 $\mu{V}$/g is obtained with a nonlinearity of 4% over $\pm$50g ranges. Flat amplitude response and frequency-proportional phase response have been obserbed, It is shown that the design and fabricaiton methods developed in the present study yield a simple, practical and effective mean for improving the performance, reliability as well as the reproducibility of the accelerometers.

Parametric Analysis of the Electric and Magnetic Field Waveforms Produced by Intracloud Lightning Discharges (운방전에 의해 발생한 전계와 자계 파형의 파라미터 분석)

  • Lee, Bok-Hee;Lee, Woo-Chul
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.20 no.2
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    • pp.81-88
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    • 2006
  • In this study, the electric and magnetic fields measuring system were designed and fabricated to investigate the electric characteristics of lightning discharges. Frequency bandwidth of electric field measuring system ranges from 40[Hz] to 2.6[MHz] and its response characteristic is 2.1[(V/m)/mV]. Frequency bandwidth of magnetic field measuring system ranges from 300[Hz] to 1[MHz] and its response characteristic is 2.8[nT/mV]. Electric and magnetic fields due to intracloud lightning discharges were observed and their waveform parameters were statistically analyzed. As a result, waveform parameters of electric and magnetic fields are nearly independent of polarity. The mean rise times and the zero-crossing times of electric and magnetic fields are approximately $5.5[{\mu}s]\;and\;21[{\mu}s]$, respectively.