• Journal of Biosystems Engineering
• /
• v.22 no.2
• /
• pp.256-265
• /
• 1997

The objectives of this study were to examine the ability to predict soluble solid and firmness in intact apples based on the visible/near-infrared spectroscopic technique. Two cultivars of apples, Delicious and Gala, were handled, tested and analyzed separately. Reflectance spectra, Magness-Tayor (MT) firmness, and soluble solids in apples were measured sequentially. Maximum and minimum diameters, height, and weight of apples were recorded before the MT firmness tests. A spectrophotometer was used to collect reflectance spectra of intact apples over a wavelength range of 400 to 2, 498 nm. The W firmness tests were conducted using a standard 11.1mm (7/16 in.) MT probe mounted in an Instron universal testing machine. A digital refractormeter was used to measure soluble solid contents in the apples. Apple samples were divided into a calibration set and a prediction set. The calibration set was used during model development, and the prediction set was used to predict soluble solids and firmness from unknown spectra. The method of partial least square (PLS) analysis was used. An unique set of PLS loading vectors (factors) was developed for soluble solid content and firmness. The PLS model showed good correlations between predicted and measured soluble solids of intact apples in 860～1078 nm of the wavelengths. However, the PLS analysis was not good enough to predict the apple firmness.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2003.02a
• /
• pp.455-460
• /
• 2003

발효공정에 있어 배양법으로는 회분식 배양법, 연속식 배양법과 유가식(fed-batch) 배양법이 있다. 이것은 발효 과정 중 기질과 균류 등의 추가 투입 및 추출에 따른 분류로서 특히, 유가식 배양의 경우 배양액의 농도가 너무 높거나 낮으면 에탄올의 생산이 많아지거나 효모의 성장 속도가 늦어지게 된다 유가식 공정은 항생제, 비타민, 아미노산, 효소 및 재조합 단백질 등의 생산에 주로 이용된다. (중략)

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2003.07a
• /
• pp.462-468
• /
• 2003

최근 전자산업의 발달로 첨단기술의 농업적 응용에 필요한 각종 센서가 개발되고 있어 이를 이용한 농산물의 각종 품질을 비 파괴적으로 측정할 수 있는 연구가 활발히 진행되고 있다. 여러 농산물 중과실의 경도와 같은 물성 인자는 그 중요성에도 불구하고 비 파괴적으로 측정할 수 있는 기술이 개발되고 있지 않고 있다. 레이저 분광법의 경우 표면의 광 산란현상을 이용하여 경도를 비교적 정확하게 측정할 수 있으나 아직까지는 시스템의 가격이 고가이며 사용에 많은 제약이 따르며 근적외선 분광분석법을 이용한 경도 측정은 현재까지 그 정확도가 낮다. (중략)

• Korean Journal of Food Science and Technology
• /
• v.28 no.5
• /
• pp.916-921
• /
• 1996

This study was conducted to measure fat contents of potatochips by near infrared spectroscopy (NIRS). Both potatochip powder and potatochips were used to find correlations between the absorbance at certain wavelengths find the fat contents. Based on the correlation analysis, linear regression models predicting the fat contents were developed to predict the fat contents. Artificial neural network (ANN) models were also developed. Predicted values were compared to the measured ones. The regression and the ANN model predicting the fat contents of potatochip powder had determination coefficients of 0.93 and 0.92, and standard errors of prediction (SEP) of 1.29% and 1.17%, respectively. The correlation analysis of potatochips showed that the determination coefficients were low. Therefore, the fat contents of not potatochips but potatochip powder could be measured by NIRS.

• Journal of Animal Environmental Science
• /
• v.13 no.2
• /
• pp.113-120
• /
• 2007

This study was conducted to measure Nitrogen(N), Phosphate($P_2O_5$), Potassium ($K_2O$), Organic matter(OM) and Moisture content of liquid pig manure by Near Infrared Spectroscopy(NIRS) and to develop an alternative and analytical instrument which are used for measurement of N, $P_2O_5$, $K_2O$, OM, and Moisture contents for liquid pig manure. The liquid pig manure sample's transmittance spectra were measured with a NIRS in the wavelength range of 400 to 2,500 nm. Multiple linear regression and partial least square regression were used for calibrations. The correlation coefficient(RSQ) and standard error of calibration(SEC) obtained for nitrogen were 0.9190 and 2.1649, respectively. The RSQ for phosphate, potassium, organic matter and moisture contents were 0.9749, 0.5046, 0.9883 and 0.9777, and the SEC were 0.5019, 1.9252, 0.1180 and 0.0789, respectively. These results are indications of the rapid determination of components of liquid pig manure through the NIR analysis. The simple analytical instrument for liquid pig manure consisted of a tungsten halogen lamp for light source, a sample holder, a quartz cell, a SM 301 spectrometer for spectrum analyzer, a power supply, an electronics, a computer and a software. Results showed that the simple analytical instrument that was developed can approximately predict the phosphate, organic matter and moisture content of the liquid pig manure when compared to the analysis taken by NIRS. The low predictability value of potassium however, needs further investigation. Generally, the experiment proved that the simple analytical instrument was reliable, feasible and practical for analyzing liquid pig manure.

• Journal of the Korean Chemical Society
• /
• v.49 no.6
• /
• pp.531-536
• /
• 2005

• Journal of the Korean Wood Science and Technology
• /
• v.49 no.3
• /
• pp.213-225
• /
• 2021

In this paper, we investigated the carbonization characteristics of lignin hydrochar prepared by hydrothermal carbonization and established a model for predicting the carbonization degree using near-infrared spectroscopy and partial least squares regression. The carbon content of the hydrothermally carbonized lignin at the temperature of 200 ℃ was higher by approximately 3 wt% than that of the untreated sample, and the carbon content tended to gradually increase as the heating time increased. Hydrothermal carbonization made lignin more carbon-intensive and more homogeneous by eliminating the microparticles. The discriminant and predictive models using near-infrared spectroscopy and partial least squares regression approppriately determined whether hydrothermal carbonization has been applied and predicted the carbon content of hydrothermal carbonized lignin with high accuracy. In this study, we confirmed that we can quickly and nondestructively predict the carbonization characteristics of lignin hydrochar manufactured by hydrothermal carbonization using a partial least squares regression model combined with near-infrared spectroscopy.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 1999.07a
• /
• pp.282-289
• /
• 1999

선별은 청과물을 포장하기 이전에 크기, 중량, 색깔등 정해진 규격에 따라 고르는 과정을 말하고, 크게 인력선별과 기계선별, 개별선별과 공동선별로 구분한다. 국내의 경우 아직까지도 수확된 청과물은 농가단위로 개별선별하고 있으며, 중량식 선별기를 이용하여 등급선별 한 후 15kg, 10kg 상자에 포장하는 것이 가장 일반적이다. 근래에 청과물의 부가가치를 높이기 위해서 중량에 색깔을 선별할 수 있는 기능을 추가한 기계시스템이 개발되어 산업화된 바 있다(최 등, 1997). 또한 근적외선 분광분석법을 이용하여 과일의 당도를 비파괴적으로 측정 선별할 수 있는 시스템이 개발 실용화 단계에 있다(이 등, 1998). (중략)

• Analytical Science and Technology
• /
• v.15 no.2
• /
• pp.102-107
• /
• 2002

This paper describes a rapid determination of phenobarbital in intact phenobarbital tablets using partial least squares regression(PLSR) method of transmittance spectrum of near infrared (NIR) compared with the analytical data of liquid chromatograpy. The linearity, concentration range and precision of this analytical method are studied. The correlation coefficient of the calibration curve is 0.9983 and the standard error of calibration(SEC) is 0.14 %. Intra-day precision and Inter-day precision obtained in this method are CV = 0.45, CV =0.56, respectively.

• Journal of agriculture & life science
• /
• v.46 no.2
• /
• pp.49-61
• /
• 2012

This study was carried out to investigate the chemical composition and the inorganic constituents of the green tea at the 3 picking periods (Ujeon, Sejag, Jungjag) in Hadong. The results as follows ; The contents of chlorophyll, tannin, vitamin-c and total catechin were increased as picking periods increased but the contents of total nitrogen, total free amino acids, theanine and caffeine were decreased on the reverse. The inorganic constituents Mg, Ca and Mn were increased as picking periods getting late but the Na, K, B contents were decreased on the reverse. The contents of the total nitrogen, chlorophyll, total free amino acid, theanine, caffeine and total catechin and Na, Mg, Ca, B and Se were insignificant differences between Ujeon and Sejag.