• Title/Summary/Keyword: Least Square Regression

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Prediction of Nutrient Composition and In-Vitro Dry Matter Digestibility of Corn Kernel Using Near Infrared Reflectance Spectroscopy

  • Choi, Sung Won;Lee, Chang Sug;Park, Chang Hee;Kim, Dong Hee;Park, Sung Kwon;Kim, Beob Gyun;Moon, Sang Ho
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.34 no.4
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    • pp.277-282
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    • 2014
  • Nutritive value analysis of feed is very important for the growth of livestock, and ensures the efficiency of feeds as well as economic status. However, general laboratory analyses require considerable time and high cost. Near-infrared reflectance spectroscopy (NIRS) is a spectroscopic technique used to analyze the nutritive values of seeds. It is very effective and less costly than the conventional method. The sample used in this study was a corn kernel and the partial least square regression method was used for evaluating nutrient composition, digestibility, and energy value based on the calibration equation. The evaluation methods employed were the coefficient of determination ($R^2$) and the root mean squared error of prediction (RMSEP). The results showed the moisture content ($R^2_{val}=0.97$, RMSEP=0.109), crude protein content ($R^2_{val}=0.94$, RMSEP=0.212), neutral detergent fiber content ($R^2_{val}=0.96$, RMSEP=0.763), acid detergent fiber content ($R^2_{val}=0.96$, RMSEP=0.142), gross energy ($R^2_{val}=0.82$, RMSEP=23.249), in vitro dry matter digestibility ($R^2_{val}=0.68$, RMSEP=1.69), and metabolizable energy (approximately $R^2_{val}$ >0.80). This study confirmed that the nutritive components of corn kernels can be predicted using near-infrared reflectance spectroscopy.

Estimation of Kinetic Parameters of Nonenzymatic Browning Reaction Using Equivalent Time at Reference Temperarture with Linearly Increasing Temperature Profile (정속가열(定速加熱)조건에서 표준온도상당시간(相當時間)을 이용한 비효소적 갈색화 반응의 동력학 파라미터 추정(推定))

  • Cho, Hyung-Yong;Kwon, Yun-Joong;Kim, In-Kyu;Pyun, Yu-Ruamg
    • Korean Journal of Food Science and Technology
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    • v.25 no.2
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    • pp.178-184
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    • 1993
  • The procedure using equivalent time at reference temperature has been assessed for the estimation of kinetic parameters with experimental data. Kinetic studies of nonenzymatic browning reaction in model and food system were carried out with linearly increasing temperature method. These kinetic parameters, n, $k_{ref}$ and $E_a$ of the systems were evaluated from original data in one step by nonlinear least square regression. The one step procedure yielded efficiently accurate parameter estimation. Computer simulated data with the kinetic models were well consistent with experimental data (average correlation coefficient=0.96).

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Evaluation of Chemical Composition in Reconstituted Tobacco Leaf using Near Infrared Spectroscopy (근적외선 분광분석법을 이용한 판상엽 화학성분 평가)

  • Han, Young-Rim;Han, Jungho;Lee, Ho-Geon;Jeh, Byong-Kwon;Kang, Kwang-Won;Lee, Ki-Yaul;Eo, Seong-Je
    • Journal of the Korean Society of Tobacco Science
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    • v.35 no.1
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    • pp.1-6
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    • 2013
  • Near InfraRed Spectroscopy(NIRS) is a quick and accurate analytical method to measure multiple components in tobacco manufacturing process. This study was carried out to develop calibration equation of near infrared spectroscopy for the prediction of the amount of chemical components and hot water solubles(HWS) of reconstituted tobacco leaf. Calibration samples of reconstituted tobacco leaf were collected from every lot produced during one year. The calibration equation was formulated as modified partial least square regression method (MPLS) by analyzing laboratory actual values and mathematically pre-treated spectra. The accuracy of the acquired equation was confirmed with the standard error of prediction(SEP) of chemical components in reconstituted tobacco leaf samples, indicated as coefficient of determination($R^2$) and prediction error of sample unacquainted, followed by the verification of model equation of laboratory actual values and these predicted results. As a result of monitoring, the standard error of prediction(SEP) were 0.25 % for total sugar, 0.03 % for nicotine, 0.03 % for chlorine, 0.16 % for nitrate, and 0.38 % for hot water solubles. The coefficient of determination($R^2$) were 0.98 for total sugar, 0.97 for nicotine, 0.96 for chlorine, 0.98 for nitrate and 0.92 for hot water solubles. Therefore, the NIRS calibration equation can be applicable and reliable for determination of chemical components of reconstituted tobacco leaf, and NIRS analytical method could be used as a rapid and accurate quality control method.

Somatic cell counts determination in cow milk by near infrared spectroscopy: A new diagnostic tool

  • Tsenkova, R.;Atanassova, S.;Kawano, S.;Toyoda, K.
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.4104-4104
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    • 2001
  • Milk somatic cell count (SCC) is a recognized indicator of cow health and milk quality. The potential of near infrared (NIR) spectroscopy in the region from 1100 to 2500nm to measure SCC content of cow milk was investigated. A total of 196 milk samples from 7 Holstein cows were collected for 28 days, consecutively, and analyzed for fat, protein, lactose and SCC. Three of the cows were healthy, and the rest had mastitis periods during the experiment. NIR transflectance milk spectra were obtained by the InfraAlyzer 500 spectrophotometer in a wavelength range from 1100 to 2500 nm. The calibration for logSCC was performed using partial least square (PLS) regression and different spectral data pretreatment. The best accuracy of determination was found for equation, obtained using smoothed absorbance data and 10 PLS factors. The standard error of calibration was 0.361, calibration coefficient of multiple correlation 0.868, standard error of prediction for independent validation set of samples 0.382, correlation coefficient 0.854 and the variation coefficient 7.63%. The accuracy of logSCC determination by NIR spectroscopy would allow health screening of cows, and differentiation between healthy and mastitic milk samples. When the spectral information was studied it has been found that SCC determination by NIR milk spectra was indirect and based on the related changes in milk composition. In the case of mastitis, when the disease occurred, the most significant factors that simultaneously influenced milk spectra were alteration of milk proteins and changes in ionic concentration of milk.

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Quality Prediction of Kiwifruit Based on Near Infrared Spectroscopy

  • Lee, Jin Su;Kim, Seong-Cheol;Seong, Ki Cheol;Kim, Chun-Hwan;Um, Yeong Cheol;Lee, Seung-Koo
    • Horticultural Science & Technology
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    • v.30 no.6
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    • pp.709-717
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    • 2012
  • To establish the standard of ripe kiwifruit sorting, near infrared (NIR) spectroscopy was performed on kiwifruit sampled from three farms. Destructive measurements of flesh firmness, soluble solids content (SSC), and acidity were performed and compared to measurement using NIR reflectance spectrums from 408 to 2,492 nm. NIR predictions of those quality factors were calculated using the modified partial least square regression method. Flesh firmness was predicted with a standard error of prediction (SEP) of 3.32 N and with a correlation coefficient ($R^2$) of 0.88. SSC was predicted with SEP of $0.49^{\circ}Brix$ and with $R^2$ of 0.98. Acidity was predicted with SEP of 0.28% and with $R^2$ of 0.91. Kiwifruit ripened at $20^{\circ}C$ for 15 days showed uneven qualities with normal distribution. Considering the SEP of each parameter, kiwifruit after ripening treatment could be non-destructively predicted their qualities and sorted by flesh firmness or soluble solids content through NIR prediction.

Impact of Comorbid Obsessive Compulsive Symptoms on Quality of Life in Stable Patients with Chronic Schizophrenia (안정화된 만성 조현병 환자에서 강박장애 증상이 삶의 질에 미치는 영향)

  • Moon, Jung Yoon;Kang, Sukhoon;Seok, Jung-Ho;Kim, Chan-Hyoung;Kim, Tae Yong;Choi, Jin Hee;So, Hyong Seok
    • Anxiety and mood
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    • v.13 no.2
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    • pp.141-147
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    • 2017
  • Objective : This study aimed to evaluate the relationship between comorbid obsessive compulsive disorder (OCD) and quality of life in stable patients with schizophrenia. Methods : We interviewed 162 symptom-stable inpatients who have been on a constant dose of antipsychotics for at least 3 months prior and diagnosed as chronic schizophrenia. Subsequently, patients were classified according to the existence of OCD as evaluated using the Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV). Further, all clinical and demographic data were collected and evaluated. To investigate potential interrelationships, the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), Korea-Positive and Negative Symptom Scale (K-PANSS), Korean Modification of the Scale to Measure Subjective Well-Being under Neuroleptic Treatment (KmSWN) and Korean Version Quality of Life Scale (K-QOLS) were performed. Independent t-test and Chi-square test were used to compare groups and regression analysis was done to assess the relationship between the Y-BOCS and quality of life. Results : Schizophrenia patients with OCD showed significantly earlier onset of schizophrenia, more severe psychiatric symptoms and lower quality of life, compared to those without comorbid OCD. OCD might be associated with lower quality of life in schizophrenia. Conclusion : Schizophrenia patients with OCD showed lower quality of life than those without OCD. In the treatment for schizophrenia, evaluation of OCD might be needed to improve their quality of life and social function.

Development of Electronic Mapping System for N-fertilizer Dosage Using Real-time Soil Organic Matter Sensor (실시간 토양 유기물 센서와 DGPS를 이용한 질소 시비량 지도 작성 시스템 개발)

  • 조성인;최상현;김유용
    • Journal of Biosystems Engineering
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    • v.27 no.3
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    • pp.259-266
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    • 2002
  • It is crucial to know spatial soil variability for precision farming. However, it is time-consuming, and difficult to measure spatial soil properties. Therefore, there are needs fur sensing technology to estimate spatial soil variability, and for electronic mapping technology to store, manipulate and process the sampled data. This research was conducted to develop a real-time soil organic matter sensor and an electronic mapping system. A soil organic matter sensor was developed with a spectrophotometer in the 900∼1,700 nm range. It was designed in a penetrator type to measure reflectance of soil at 15cm depth. The signal was calibrated with organic matter content (OMC) of the soil which was sampled in the field. The OMC was measured by the Walkeley-Black method. The soil OMCs were ranged from 0.07 to 7.96%. Statistical partial least square and principle component regression analyses were used as calibration methods. Coefficient of determination, standard error prediction and bias were 0.85 0.72 and -0.13, respectively. The electronic mapping system was consisted of the soil OMC sensor, a DGPS, a database and a makeshift vehicle. An algorithm was developed to acquire data on sampling position and its OMC and to store the data in the database. Fifty samples in fields were taken to make an N-fertilizer dosage map. Mean absolute error of these data was 0.59. The Kring method was used to interpolate data between sampling nodes. The interpolated data was used to make a soil OMC map. Also an N-fertilizer dosage map was drawn using the soil OMC map. The N-fertilizer dosage was determined by the fertilizing equation recommended by National Institute of Agricultural Science and Technology in Korea. Use of the N-fertilizer dosage map would increase precision fertilization up to 91% compared with conventional fertilization. Therefore, the developed electronic mapping system was feasible to not only precision determination of N-fertilizer dosage, but also reduction of environmental pollution.

Prediction of Pear Fruit Firmness by Analysis of Laser-induced Light Backscattering Images (레이저 역산란 광 영상분석에 의한 배 경도 예측)

  • Lee, Kyeong-Hwan;Suh, Sang-Ryong;Yu, Seung-Hwa;Yoo, Soo-Nan;Choi, Young-Soo
    • Journal of Biosystems Engineering
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    • v.36 no.5
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    • pp.369-376
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    • 2011
  • The overall goal of this study was to examine the feasibility of predicting firmness of pear fruit by analyzing laser-induced light backscattering images. Thirty-five image analysis characteristics extracted from the laser-induced light backscattering images were used to build partial least squares regression (PLSR) models for predicting firmness of pear fruit. Experiments were conducted with three sets of pear samples which were in same "Shingo" cultivar, harvested in a same season, but produced in different counties. In every experiments with fruit samples produced in a same county, the correlation coefficients of prediction ($r_p$) and root mean square errors of prediction (RMSEP) of the models were 0.550~0.761 and 4.039~6.154 N, respectively. In an experiment with mixed fruit samples produced in different counties, the $r_p$ and RMSEP of the model were 0.669 and 5.02 N, respectively. The experiment results indicate that the analysis of laser-induced light backscattering images could be a useful tool for predicting firmness of pear fruit nondestructively.

Sampling and Calibration Requirements for Optical Reflectance Soil Property Sensors for Korean Paddy Soils (광반사를 이용한 한국 논 토양 특성센서를 위한 샘플링과 캘리브레이션 요구조건)

  • Lee, Kyou-Seung;Lee, Dong-Hoon;Jung, In-Kyu;Chung, Sun-Ok;Sudduth, K.A.
    • Journal of Biosystems Engineering
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    • v.33 no.4
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    • pp.260-268
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    • 2008
  • Optical diffuse reflectance sensing has potential for rapid and reliable on-site estimation of soil properties. For good results, proper calibration to measured soil properties is required. One issue is whether it is necessary to develop calibrations using samples from the specific area or areas (e.g., field, soil series) in which the sensor will be applied, or whether a general "factory" calibration is sufficient. A further question is if specific calibration is required, how many sample points are needed. In this study, these issues were addressed using data from 42 paddy fields representing 14 distinct soil series accounting for 74% of the total Korean paddy field area. Partial least squares (PLS) regression was used to develop calibrations between soil properties and reflectance spectra. Model evaluation was based on coefficient of determination ($R^2$) root mean square error of prediction (RMSEP), and RPD, the ratio of standard deviation to RMSEP. When sample data from a soil series were included in the calibration stage (full information calibration), RPD values of prediction models were increased by 0.03 to 3.32, compared with results from calibration models not including data from the test soil series (calibration without site-specific information). Higher $R^2$ values were also obtained in most cases. Including some samples from the test soil series (hybrid calibration) generally increased RPD rapidly up to a certain number of sample points. A large portion of the potential improvement could be obtained by adding about 8 to 22 points, depending on the soil properties to be estimated, where the numbers were 10 to 18 for pH, 18-22 for EC, and 8 to 22 for total C. These results provide guidance on sampling and calibration requirements for NIR soil property estimation.

Determinants of E-Intermediary Use in Export Marketing: Cross-National Differences in the US and Korean SMEs

  • Cho, Hyuk-Soo
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2008.10a
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    • pp.464-486
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    • 2008
  • Purpose. Electronic intermediaries (e-intermediaries) are gaining significance in international marketing with the rapid development of e-commerce. The goal of this study is to explain empirically what leads to a higher use of this relatively new exportation alternative. Relying on a resource-based view as our research foundation, we focus on information technology (IT) and non-IT factors as possible determinants. Further, this study brings arguments offered by transaction cost theorists to explain the other non-IT determinants. Methodology/Approach. Data are collected from small and medium-sized enterprises (SMEs) in the electronic industry in Korea and the U.S to ensure generalizability. Ordinary least square (OLS) regression is utilized to analyze the data. Findings. This study raises new issues regarding a relatively new type of exporting channel, e-intermediary. Exporting is regarded as the most appropriate strategy for SMEs in international commerce. A number of SMEs stay away from exporting due to limited resources or lack of knowledge regarding foreign markets. The findings in this study should help SMEs use e-intermediaries more widely by developing appropriate IT-related resources (IT-related human and relationship assets) and dealing with non-IT factors (international competence, environmental uncertainty, and duration of relationship) effectively. Originality/Value/Contribution. This study illustrates the significant role of e-intermediaries, which may help SMEs to penetrate the global market effectively. Finding relevant sources in the global e-marketplace is a challenge for non-experienced users like SMEs. This study proposes e-intermediaries as an effective alternative for them. Another contribution of this study is to show how the use of indirect exporting channels, e-intermediaries, decrease costs in exporting transactions. This study suggests an e-intermediary as a hybrid exporting channel to balance risk and profit.

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