• Journal of the Korean Wood Science and Technology
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• 제30권2호
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• pp.108-114
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• 2002

변장 14.0 cm와 16.5 cm인 소나무 정각재의 가열판진공건조와 고주파진공건조간의 건조속도, 함수율분포와 비(比)에너지를 비교하였다. 고주파진공건조는 가열판진공건조보다 건조속도 및 변장이 건조속도에 미치는 영향이 컸었다. 가열판진공건조 목재의 재장방향, 두께방향과 폭방향의 함수율분포는 볼록 형태를 나타내었고, 고주파진공건조 목재는 오목 형태를 나타내었다. 가열판진공건조 목재의 폭방향과 두께방향간의 수분경사는 유사하였으나 고주파진공건조 목재의 경우는 폭방향의 수분경사가 두께방향보다 완만하였다. 가열판진공건조와 고주파 진공건조의 비(比)에너지곡선은 함수율이 감소할수록 증가하는 경향을 나타내었고, 가열판진공건조의 비(比)는 고주파진공건조보다 컸었다.

• 한국가구학회지
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• 제10권2호
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• pp.29-36
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• 1999

During a radio-frequency/vacuum plus press drying process of some hardwood veneers for decoration we investigated the effect of a grain and thickness of a veneer sheet on drying rates, variations of final moisture content within a bundle of veneer sheets, and formation of checking, end waving, and burning mark. About thirty three hundreds sheet of veneer could be dried in sixty five hours from green to in0-use moisture content, and a final moisture content was significantly effected by initial moisture content of veneer. There were nearly variations in a final moisture content among the veneer sheets in the same bundle. A checking was never found in a edge-sliced veneer, and very slight in a flat-sliced veneer of ash and red oak. There were no end waving and no burning mark in all veneer sheets.

• Journal of the Korean Wood Science and Technology
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• 제29권1호
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• pp.1-8
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• 2001

소나무, 잣나무, 낙엽송과 웨스턴 햄록의 5두께(3, 5, 7, 9 및 11cm) 제재를 3가지 종류의 건조스케줄을 적용한 가열판 압체식 진공건조에서 건조중 함수율, 제재두께와 건조속도의 관계, 제재두께와 건조시간계수의 관계 등을 구명한 결과에서 제재두께 초기함수율 및 건조시간에 따른 건조중 함수율을 추정할 수 있었다. 그리고 함수율 30%에서 15% 범위에서 평균 건조속도는 웨스턴 햄록이 가장 컸고 다음은 소나무, 잣나무, 낙엽송 순위였으며, 제재두께가 증가함에 따라 곡선적으로 감소하였다. 또한 건조시간계수는 제재두께가 증가함에 따라 곡선적으로 증가하였다.

• Journal of the Korean Wood Science and Technology
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• 제29권1호
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• pp.9-15
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• 2001

침엽수 4수종(소나무, 잣나무, 낙엽송, 웨스턴 햄록)의 가열판 압체식 진공건조에서 소요되는 비에너지 곡선은 함수율 감소에 따라 서서히 증가, 거의 일정, 급속 증가 등 3단계의 증가 패턴을 나타내었고, 제재두께별 계산된 비에너지는 3cm 제재 0.483, 5cm 제재 0.649, 7cm 제재 0.814, 9cm 제재 0.977 및 11cm 제재 1.138kWh/kg로서 두께가 증가함에 따라 거의 직선적으로 증가하였고, 강한 건조스케줄을 적용한 비에너지는 약한 건조스케줄의 것보다 적었으며, 가열판 진공건조의 평균 비에너지는 0.712kWh/kg으로서 다른 건조법의 것보다 적었다.

• Journal of the Korean Wood Science and Technology
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• 제21권2호
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• pp.39-48
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• 1993

End-matched disks of 7.7cm thickness were part-time dried in vacuum press dryer to investigate the drying characteristics by using drying schedules and end treatments. The ginkgo disks could be dried faster with severer end checks and ring failures by C schedule than by S schedule. There were no significant differences in drying rates and amounts of end checks, ring failures and V-shaped checks occurred between ginkgo disks end-taped with Korean traditional paper (KTP) and those untreated. The drying time of walnut disks was slightly reduced by end-taping with KTP. And the length of end checks and V-shaped checks and the frequency of defected disk were decreased more effectively than those untreated. The tangential strains and tangential drying stresses near bark sides of ginkgo and walnut disk untreated were developed in the early stage of drying and incresed slightly curvi-linearly above fiber saturation point (fsp) and more curvi-linearly below fsp. The influence of end-taping with KTP on the drying rate for impermeable walnut disk was stronger than that for permeable ginkgo disk.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1256-1256
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• 2001

The physico-chemical and texture characteristics of meat determine the nutritional, technological and sensory quality. However, the analysis of meat quality requires expensive, laborious and time consuming analytical methods. The objective of this study was to evaluate NIR spectroscopy using transmittance for determining the moisture, fat, protein and total pigment content, the water holding capacity (WHC) and the toughness of beef meat. A total of 318 spectra were recorded from ground beef samples by a Feed Analyzer 1265 of Infratec. The samples were obtained from the Longissimus muscle of the 10$^{th}$ rib of yearling bulls, ground with an electrical chopper, vacuum packaged, aged during 7 days and frozen at -24$^{\circ}C$ until the analyses were done. Moisture content was measured by oven drying at 10$0^{\circ}C$, fat content was determined by Soxhlet extraction and protein content was estimated from nitrogen content using the Kjeldahl analysis. The total pigment content was determined by the method of Hornsey and the WHC using the method of filter paper press. The instrumental evaluation of texture (maximum load WB, maximum stress MS and toughness) was conducted in an Instron equipment with a Warner-Bratzler shearing device. This analysis was performed on a chop of 3.5 cm obtained from the longissimus of the 8$^{th}$ rib, aged during 7 days, kept frozen at -24$^{\circ}C$ and cooked before the analysis. Near infrared spectra were recorded as log 1/T (T=transmittance) at 2 nm intervals from 850 to 1050 nm using a Feed Analyzer 1265 of Infratec. Calibrations were performed with the WinISI software (vs. 1.02) using the MPLS method. To examine the effect of scatter correction o. derivation of spectra on the calibration performance, calibrations were calculated with the crude spectra or pretreated with different mathematical treatments (inverse MSC, SNVD) and/or second derivative operation. For chemical composition, the use of the scatter corrections improved the calibration statistics, in terms of lower SECV and higher $r^2$. In most of the variables, the use of the 2$^{nd}$ derivative improved the predictions, mainly when combined with the SNVD treatment. However, for predicting the texture traits, the best estimation was obtained from the crude spectrum. These results showed that the equations obtained for predicting moisture, fat and total pigments were very accurate, with $r^2$ being higher that 0.9. However, the prediction of the texture traits (WB, MS, toughness) from ground meat was poor.