• Title/Summary/Keyword: Least-Mean-Square

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Perception of Foodborne Illness Prevention and Personal Hygiene Practice (중학생의 식중독 예방에 대한 인식도와 개인 위생 실천)

  • Seo, Sun-Hee;Ryu, Kyung-Mi
    • Korean journal of food and cookery science
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    • v.24 no.3
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    • pp.294-303
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    • 2008
  • The purpose of this study was to investigate middle school students` perceptions on foodborne illness prevention in relation to their personal hygiene practices. The survey was administered in July, 2007 at one middle school, with a total of 390 students participating. The self-completed questionnaire consisted of several questions regarding the students` awareness of foodborne illness, perceptions of foodborne illness prevention, and personal hygiene practices. T-tests were used to identify the differences in their perceptions of foodborne illness prevention based on gender and Chi square tests were used to identify the relationships between their perceptions of foodborne illness prevention and personal hygiene practices. Eight percent of the respondents experienced foodborne illness at least once a year and 33.8% of them have stopped eating certain foods due to anxiety towards foodborne illness. The students perceived school foods (26.0%) and street foods(17.9%) as the main sources of foodborne illness, and dairy products(20.0%) and fresh fish (19.7%) were considered foods having the greatest potential for causing foodborne illness. Many students were aware of Escherichia coli O157(43.1%) and Hepatitis A(23.3%), but only a few recognized Clostridium botulinum(4.1%) and Salmonella(7.9%), even though these are major foodborne illness-causing pathogens. The students considered foodborne illness prevention very important(mean = 4.33); also, the results showed that many washed their hands 3-4 times (34.1%) and 5-6 times(29.2%) per day. Hand washing frequency was significantly related to the perceived importance of personal hygiene practice as well as to education on safety and sanitation. However, the students` perception on the importance of personal hygiene practices were not significantly different based on having received safety and sanitation education. Ultimately, these results will be used to develop guidelines for effective education on safety and sanitation.

A study of estimation for excess attenuation of Noise propagated on the ground (지표면상을 전파하는 소음의 초과감쇠 산정방법에 관한 연구)

  • Oh, J.E.;Kim, D.G.;Yim, T.K.
    • The Journal of the Acoustical Society of Korea
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    • v.7 no.2
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    • pp.20-25
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    • 1988
  • This study is to explain the characteristic of excess attenuation on the ground through the outdoors experiment about noise propagation and the reduced model experiment of acoustic. The outdoors experiment on the attenuation of noise propagation was tried with the small engine that had large acoustic output, and then it was conformed that there was relationship between the excess attenuation calculated by measurement from distance attenuation and Log(D/(Hs+Hr)). As a result, it was found that the attenuation of noise propogation depended upon the direction of the wind and frequency and was regressed in a straight line. And the numerical values of excess attenuation on the ground could be calculated by regarding Log(D/(Hs+Hr)) as a parameter with an airing resistance $\sigma$. It was found that when the mean square error between the excess attenuation calculated by measurement and the value calculated by a fomula $L=-20Log\mid1+(r_1/r_2)Qexp(ik, \bigtriangleup r)\mid$ about optional $\sigma$ was least, the optimal decision of u was made. As the characteristic of model is the model experiment on a reduced scale of 1 to 40, It was conformed that it corresponds enough with the measurement value with measuring the distance attenuation in the large anecoic chamber.

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The Statistical on Numerical Analysis for The Petrology and Bulk Chemical Composition. In Cheju Volcanic Island (제주화산도의 암석성분에 관한 통계학적인 수치해석)

  • 택훈
    • Journal of the Speleological Society of Korea
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    • v.14 no.15
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    • pp.42-90
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    • 1987
  • Lee, Moon Won reported by 63 kinds lescribing the petrography and bulk chemical Composition in Petrology of Cheju volcanic island. The total Chemical Composition data was analyzed by the program of FORTRAN77. First, the Conversition equations and the scatter diagram were examined to the analysis, by the least square method. Next, a statistical data requested a mean Value, maximum value, minimum value, the range, the standard deviation, the variance, the Standord Error and the Coefficient of variation. In the standard deviation, a small Composition is MnO and P$_2$O$\sub$5/, a large Composition is SiO$_2$, Mgo and FeO. The Standard error and the variance were the tandency looked like the Standard deviation well. However, the Coefficient Variation differs from the Standard deviation. Where, a large Coefficient of variation are H$_2$O$\^$-/ and H$_2$O$\^$+/, a small Coefficient of variation are Al$_2$O$_3$ and SiO$_2$. The Correlation of Coefficient Can be Calculated numerically from the relation between SiO$_2$, Al$_2$O$_3$ and TiO$_2$ to other Compositions.

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Validating the Entrepreneurial Intention Model on the University Students in Saudi Arabia

  • HODA, Najmul;AHMAD, Naim;AHMAD, Mobin;KINSARA, Abdullah;MUSHTAQ, Afnan T.;HAKEEM, Mohammad;AL-HAKAMI, Mwafaq
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.11
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    • pp.469-477
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    • 2020
  • The main objective of this paper is to examine the applicability of Linan and Chen's entrepreneurial intention model (EIM) in predicting the entrepreneurial intention. EIM is an adaptation of the Theory of Planned Behavior that focuses on entrepreneurial intention and hypothesizing slightly different patterns of relationship with regards to subjective norms. The model also includes human capital and demographic factors. Snowball sampling method was used to collect data using the entrepreneurial intention questionnaire (EIQ) through several social media platforms. The survey indicates that the overall entrepreneurial intention of Saudi students is high (mean = 5.41). Eight out of the seventeen hypothesized relationships were found to be significant. Among the demographic variables, gender-personal attitude was significant whereas self employment experience and years of business education were found to be significantly related with perceived behavioral control. The statistical analysis using partial least square structural equation modelling validated the model. All the three antecedents of entrepreneurial intention were significantly related with entrepreneurial intention. The results of this study will help policy makers to get deep understanding into the phenomenon of entrepreneurship among Saudi university students and thereby develop a conducive environment. This study also validates the entrepreneurial intention model in a different cultural context.

Affine Projection Algorithm for Subband Adaptive Filters with Critical Decimation and Its Simple Implementation (임계 데시메이션을 갖는 부밴드 적응필터를 위한 인접 투사 알고리즘과 간단한 구현)

  • Choi, Hun;Bae, Hyeon-Deok
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.42 no.5 s.305
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    • pp.145-156
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    • 2005
  • In application for acoustic echo cancellation and adaptive equalization, input signal is highly correlated and the long length of adaptive filter is needed. Affine projection algorithms, in these applications, can produce a good convergence performance. However, they have a drawback that is a complex hardware implementation. In this paper, we propose a new subband affine projection algorithm with improved convergence and reduced computational complexity. In addition, we suggest a good approach to implement the proposed method. In this method by applying polyphase decomposition, noble identity and critical decimation to the anne projection algorithm the number of input vectors for decorrelation can be reduced. The weight-updating formula of the proposed method is derived as a simple form that compared with the NLMS(normalized least mean square) algorithm by the reduced projection order The efficiency of the proposed algorithm for a colored input signal was evaluated by using computer simulations.

Adaptive Feedback Interference Cancellation Using Correlations for WCDMA Wireless Repeaters (WCDMA용 무선중계기에서 상관도를 이용한 적응적 궤환 간섭 제거)

  • Moon, Woo-Sik;Im, Sung-Bin;Kim, Chong-Hoon
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.44 no.7 s.361
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    • pp.35-40
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    • 2007
  • As the mobile communication service is widely used and the demand for wireless repeaters is rapidly increasing because of the easiness of extending service areas. But a wireless repeater has a problem that the output of the transmit antenna is partially fed back to the receive antenna, which results in feedback interference. In this paper, we propose a new varable step-size LMS algorithm which utilizes correlation between reference and error signals to adjust the step sizes, for cancelling the feedback interference signals in the WCDMA repeater under time-varying multi-path channels. The proposed algorithm was evaluated through computer simualation by being applied to the feedback canceling filter of the WCDMA repeater. The simulation results demonstrated that the proposed one is superior to the conventional ones in terms of the cancelation perormance.

Performance Evaluation of Equalization based On-Channel Repeater for Terrestrial Digital Multimedia Broadcast (지상파 디지털 멀티미디어 방송시스템을 위한 등화기반 동일채널 중계기의 성능분석)

  • Kim, Dong-Hyun;Park, So-Ra;Park, Sung-Ik;Yoon, Seok-Hyun;Lee, Yong-Tae
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.2A
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    • pp.210-217
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    • 2008
  • In this paper, the performance of equalization-based on-channel repeater for terrestrial DMB is analyzed. A primary concern in on-channel repeater is the performance degradation due to the echo and one of key component for on-channel repeater is the echo canceller, which usually employs LMS algorithm utilizing the repeater output as a reference for echo channel estimation and compensation. One problem using LMS algorithm is the tracking capability and there necessarily exists residual echo that has not been cancelled. To effectivelyremove the residual echo, we consider an equalization based on-channel repeater where the echo-cancellor is followed by an equalizer that performs channel estimation using pilot symbol and the channel inversion utilizing homomorphic decomposition. According to the simulation result, the performance degradation caused by the residual echo can be considerably alleviated by using the equalizer following the echo-canceller.

Impact of Multipath Fading on the Performance of the DDLMS Based Spatio Temporal Smart Antenna (다중경로페이딩이 DDLMS 기반 스마트 안테나의 성능에 미치는 영향)

  • Hong, Young-Jin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.9C
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    • pp.871-879
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    • 2009
  • The performance variations of a spatio temporal smart antenna which is equipped at the basestation of CDMA cellular communication network due to the parametric change of multipath fading environment are studied in this paper. The smart antenna of interest employs space diversity based adaptive array structure in conjunction with rake receiver that has fingers the number of which is the same as that of multipath links. The beamforming is achieved via LMS(Least Mean Square) algorithm in which a reference signal is generated using decision directed formula. It has been shown by computer simulation that the performance of our smart antenna of interest depends significantly upon not only the degree of desired signal's DOA(Direction of Arrival)spread but the number of fingers of the rake receiver. The relative insensitivity of the smart antenna's performance on desired signal's delay spread has also been observed. Computer simulation has shown that the increase of the number of fingers brings in a nonlinear enhancement of the performance of our smart antenna. The renewal of weight vector in the beamforming procedure is taken place at post PN despread stage.

Real-Time Lane Detection Based on Inverse Perspective Transform and Search Range Prediction (역원근 변환과 검색 영역 예측에 의한 실시간 차선 인식)

  • Kim, S.H.;Lee, D.H.;Lee, M.H.;Be, J.I.
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.2843-2845
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    • 2000
  • A lane detection based on a road model or feature all need correct acquirement of information on the lane in a image, It is inefficient to implement a lane detection algorithm through the full range of a image when being applied to a real road in real time because of the calculating time. This paper defines two searching range of detecting lane in a road, First is searching mode that is searching the lane without any prior information of a road, Second is recognition mode, which is able to reduce the size and change the position of a searching range by predicting the position of a lane through the acquired information in a previous frame. It is allow to extract accurately and efficiently the edge candidates points of a lane as not conducting an unnecessary searching. By means of removing the perspective effect of the edge candidate points which are acquired by using the inverse perspective transformation, we transform the edge candidate information in the Image Coordinate System(ICS) into the plane-view image in the World Coordinate System(WCS). We define linear approximation filter and remove the fault edge candidate points by using it This paper aims to approximate more correctly the lane of an actual road by applying the least-mean square method with the fault-removed edge information for curve fitting.

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Impact of environmental factors on milk β-hydroxybutyric acid and acetone levels in Holstein cattle associated with production traits

  • Ranaraja, Umanthi;Cho, Kwang Hyun;Park, Mi Na;Choi, Tae Jung;Kim, Si Dong;Lee, Jisu;Kim, Hyun Seong;Do, Chang Hee
    • Korean Journal of Agricultural Science
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    • v.43 no.3
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    • pp.394-400
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    • 2016
  • The objective of this study was to estimate the environmental factors affecting milk ${\beta}$-hydroxybutyric acid (BHBA) and acetone (Ac) concentrations in Holstein cattle. A total of 264,221 test-day records collected from the Korea Animal Improvement Association (KAIA) during the period of 2012 to 2014 were used in this study. Analysis of variance (ANOVA) was performed to determine the factors significantly affecting ketone body concentrations. Parameters considered in the model were season of test, season of calving, parity, lactation stage, and milk collecting time (AM and PM). According to the ANOVA, the $R^2$ for milk BHBA and Ac were 0.5226 and 0.4961, respectively. 'Season of test' showed a considerable influence on ketone body concentration. Least square (LS) means for milk BHBA concentrations was the lowest ($39.04{\mu}M$) in winter while it increased up to $62.91{\mu}M$ in summer. But Ac concentration did not significantly change along with 'season of test'. The means of milk BHBA and Ac concentrations were high at first lactation stage, low around second lactation stage, and then gradually increased. Cows milked in the morning had lower mean BHBA and Ac concentrations ($48.49{\mu}M$ and $121.69{\mu}M$, respectively) in comparison to those milked in the evening ($53.46{\mu}M$ and $130.42{\mu}M$, respectively). The LS means of BHBA and Ac slightly increased over parities. These results suggest that proper maintenance of milk collection, herd management programs, and evaluation of ketone body levels in milk should be considered for the efficient management of resistance to ketosis.