• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
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• pp.729-735
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• 2000

Moisture loss of fresh fruits and vegetables is a main cause of deterioration. It resulted not only in the direct quantitative loss, but also in change in appearance, texture and nutrition. To reduce the loss of moisture content during the distribution in the market, fresh products are packaged using plastic films. But, most of the fresh products are packaged manually in Korea. In order to minimize the labor requirement, the packaging machine for fruits and vegetables was developed and tested. Prototype was composed of film feeding unit, bag former, products feeding conveyor, film feeding roller, center sealer, end sealer and discharge conveyor. Green peppers, carrots and perilla leaves were tested with prototype. Prototype could pack 1780, 1390, 1780 bags per hour at the feeding speed of 0.08m/s respectively and 2250, 1810, 2640bags per hour at the feeding speed of 0.10m/s respectively. And packaging speed of green peppers and carrots was improved by 3.7 and 3.4 times compared with manual packaging. The packaging condition with the prototype was good and the products had almost no damages.

• Journal of the Korean Wood Science and Technology
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• 제26권1호
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• pp.38-50
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• 1998

Laser cutting tests were conducted to investigate the laser cutting characteristics of solid woods such as 25mm-thick white oak(Quercus acutissima) and maple(Acer mono), and wood-based panels such as 15mm-thick medium density fiberboard and particleboard. Test variables were laser power, cutting speed, grain direction, and moisture content. Specific cutting energy was measured and the qualities of cut surface were estimated in constant laser power. Specific cutting energy of white oak was larger than that of maple, and specific cutting energy of medium density fiberboard was smaller than that of particleboard. For both white oak and maple, specific cutting energy of green wood was smaller than that of air-dried wood because weight loss of moisture evaporation in green wood was larger than that in air-dried wood. In laser-cut surface, wood cells were not deformed and damaged, but in circular saw-cut surface fibers were pushed out and cut, and wood cells were deformed severely. However, mechanical surface roughness of saw-cut surface was smoother than that of laser-cut surface because of the existence of undeformed cell cavity in laser-cut surface.

• 한국산림과학회지
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• 제36권1호
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• pp.5-8
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• 1977

종가시나무와 방크스소나무의 월별(月別) 부분별(部分別) 함수율변이(含水率變異)를 조사(調査)하여 본바 양자(兩者) 공(共)히 기건함수율(氣乾含水率)은 부위별(部位別)이나 월별(月別)로 유의의(有意義)한 차이(差異)를 보이지 않았으나 생재함수율(生材含水率)은 전자(前者)가 부위별(部位別)로는 중부(中部)가 최소(最小) 상부(上部)가 최대(最大), 계절별(季節別)로는 하계(夏季)에 최소(最小) 추계(秋季) 최대치(最大値)를 보였으며 후자(後者)는 부위(部位)에 있어서 하부(下部)에 최소(最小), 상부(上部)에 최대(最大), 계절별(季節別)로는 동계(冬季)에 최소(最小) 하계(夏季)에 최대치(最大値)를 보였다.

• 한국식품저장유통학회지
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• 제16권6호
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• pp.843-848
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• 2009

탈수제(maltodextrin)와 탈수제 첨가로 분리된 탈수액을 농도별로 첨가한 분자압축탈수방법으로 건조시 킨 고추분말, 동결건조와 열풍건조 시킨 고추분말의 품질을 비교 평가하였다. 분자압축탈수 건조한 고추분말의 수분함량, 색도측정, 항산화활성 측정, capsaicinoids 함량, 관능평가를 분석한 결과 수분함량의 경우 동결건조와 열풍건조 그리고 분자압축탈수의 건조 방식이 달라차이가 나타났지만 분자압축탈수를 이용한 건조에서는 탈수제 첨가보다 재사용 탈수액 첨가가 최종수분함량이 낮게 나타났다. 색도는 분자압축탈수방법으로 이용된 탈수제와 재사용 탈수액 첨가농도가 증가할수록 명도(lightness)가 조금씩 증가하였다. 항산화활성측정은 분자압축탈수 건조한 고추분말의 시료가 합성항산화제 BHA, BHT의 보다는 낮게 나타났지만 동결건조분말과 열풍건조분말보다는 높게 나타났다. 천연 항산화제인 alpha-tocopherol과는 차이가 나타나지 않았다. Capsaicinoids 함량은 탈수제 및 재사용 탈수액 농도의 증가에 따라 낮아졌다. 관능평가에서는 색(color), 외관(external), 향기(flavor), 맛(taste) 및 전체적인 기호도(overall acceptabil를)에 대하여 동결건조분말과 열풍건조분말보다 분자압축탈수방법을 이용한 고추분말이 우수하였다. 그러므로 본 연구에서는 동결건조 및 열풍건조 처리한 고추분말보다 분자압축탈수방법을 이용한 고추가 고품질 고추분말제품을 활용하는데 우수하다고 판단된다.

• Journal of the Korean Wood Science and Technology
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• 제31권4호
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• pp.31-37
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• 2003

국내에 많이 조림되어 있는 은사시나무(Populus alba×P. glandulosa)의 효율적인 건조를 위해 기본적인 물리적 성질을 조사하였다. 캠퍼스에서 벌채한 원목을 32 mm 판목 판재로 제재하여 관행열기건조(저온건조), 고온건조, 마이크로파-진공(MW/V)건조의 3가지 방식으로 건조하여 건조속도, 건조결함, 길이방향 수분경사, 색상 등을 비교하였다. 평균생재비중(전건무게-생재부피 기준)은 0.349±0.074였으며, 심재의 생재함수율은 200% 내외, 변재는 100%내외로 심재 함수율이 더 높았다. 생재에서 전건까지의 수축율은 방사방향과 접선방향이 각각 2.4%와 7.3%였으며 심·변재간 차이는 없었다. 생재에서 함수율 10%까지 건조시간은 컨디쇼닝시간을 제외하고 저온건조는 65시간, 고온건조는 35시간, MW/V건조는 22시간이었으며, 건조목 표면을 색차계로 조사한 결과 MW/V건조 판재의 색상이 가장 밝고 깨끗하였다.

• 한국식품저장유통학회지
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• 제13권2호
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• pp.228-233
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• 2006

본 연구는 뜰보리수의 영양성분의 함량과 성숙 증에 이들 변화를 조사하여 식품학적 가치를 평가하고자 하였다. 들보리수의 수분함량은 성숙함에 따라 감소하였고 당도 (brix)는 증가하는 경향이었다. 탄수화물(무질소화합물)은 성숙함에 따라 증가하였으나 조단백질의 함량은 감소하였다. 환원당의 함량은 수용성 단백질과 달리 성숙중에 증가 하였다. 유리당 함량은fructose와 glucose의 함량이 높았으며, 이들의 함량은 성숙 중에 현저하게 증가하였다. 미숙과 실의 총 유리당의 함량은 135.66 mg/100 g-fr.wt 이었으나 완숙과 과숙과실에서는 각각 544.26. 787.83 mg/100 g-fr.wt 으로 급격히 증가하였다. 유기산의 조성은 acetic, citric, lactic, malic, succinic acid 이었으며, citric acid의 함량이 가장 높았다. 총유기산의 함량은 미숙 과실일때 407.95 mg/100 g-fr.wt이었고, 성숙 중에 급격하게 감소하였다. 환원형 비타민 C의 함량은 미숙 과실일 때 56.98 mg/100 g-fr.wt이었으며, 성숙 중에 감소하는 경향이었고, 총 비타민 C의 함량도 성숙 중에 감소하였다. 폴리페놀의 함량은 411.39 mg/100 g-fr.wt이었으며, 완숙과에서는 293.41 mg/100 g-fr.wt으로 성숙 중에 현저히 감소하였다.

• 한국환경과학회지
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• 제22권1호
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• pp.17-23
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• 2013

In order to evaluate the effect of various organic soil conditioner ratios on the soil moisture content and growth of Cotoneaster horizontalis, a container type for wall-planting experiment was conducted in a greenhouse at Konkuk University under non-irrigation. The experimental planting grounds were prepared with different organic soil conditioner ratios ($A_1L_0$, $A_8L_1$, $A_4L_1$ $A_2L_1$ and $A_1L_1$), and a drought-tolerant ornamental variety of Cotoneaster horizontalis was planted. The change in soil moisture content, plant height, number of branches, number of dead leaves, number of leaves, number of shoots, length of node, length of leaf, width of leaf, root-collar caliper, chlorophyll content, and survival rate were investigated, from April to Jun 2010. The results of soil moisture content measurements were analyzed with weight units in the container type for wall-planting during the dry summer season. The soil moisture contents were significantly enhanced in the container type for wall-planting in increasing order as the amount of soil conditioner level was increased ($A_1L_1$ > $A_2L_1$ > $A_4L_1$ > $A_8L_1$ > $A_1L_0$). Compared to the control treatment application (amended soil with 100% + organic soil conditioner 0%), the highest plant growth was observed in the treatment of $A_1L_1$ application (amended soil with 50% + organic soil conditioner 50%). However, the differences between the organic soil conditioner ratio treatments of $A_1L_1$, $A_4L_1$, and $A_8L_1$ organic soil conditioner application were mostly not significant. The survival rate increased with the increasing application of organic soil conditioner, but in the control treatment application all the plants died. The experimental results from clearly demonstrated that the organic soil conditioner improved the survival rate more than the growth of Cotoneaster horizontalis. Therefore, Cotoneaster horizontalis is expected to be a highly valuable shrub for green wall systems, when considered for us in integration system or for increasing soil water contents in planting grounds.

• Journal of the Korean Wood Science and Technology
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• 제51권6호
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• pp.447-447
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• 2023

This study aimed to convert underutilized moso bamboo into high-value added products such as fences, interior materials, lighting fixtures, and accessories. Green moso bamboo poles with a diameter of approximately 10 cm and a length of approximately 3.7 m were heat treated at 140℃ using a large-scale kiln. The processing time was meticulously adjusted through various stages, including pretreatment (6-8 hours at 60℃), cooking (8-10 hours at 100℃), steaming (26-30 hours at 120℃), heating (4-6 hours at 140℃), and finally, cooling (below 80℃). A meticulously designed heat treatment process has enabled efficient mass production of moso bamboo poles with improved qualities, including minimal splitting, moisture levels below 3%, and a specific gravity of 1.05. The focus of this study was to present the physical and drying properties, such as color, dimensional change, specific gravity, moisture content, and splitting, observed during the heat treatment process.

• 한국가구학회지
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• 제17권1호
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• pp.33-46
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• 2006

This study was carried out to investigate a radio-frequency/vacuum (RF/V) drying ability and physical properties of the green boards and the pre-kiln dried boards with 40 mm thickness, and the 70 mm-thick green board of Iroko (Milicia excelsa). The major results were summarized as follows; The drying time from initial moisture content (MC) of 110% to approximate 6% MC for a 40mm-thick green board was 192 hours, and about 200 hours for the 70 mm-thick green board, respectively and so the RF/V drying times were dramatically shortened compared to conventional kiln drying time. The case hardenings at the RF/V drying completion stage test were very negligible, thus represented almost no existence of the residual stress. The checks were very slightly formed on all of the boards during the RF/V drying test, but crook appeared quite severely. During the accelerating test, the water-resistant treated specimens had not experienced any signs of checking occurred, whereas the control boards had encountered very frequent occurrences of end checking and slight surface checking. There were no observations of warping and discoloring regardless of the treatment.

• Journal of the Korean Wood Science and Technology
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• 제39권2호
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• pp.125-131
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• 2011

The characteristics of radio-frequency/vacuum drying Japanese larch boxed heart round logs with 150 mm and 210 mm in diameter and 2,500 mm in length, subjected to compressive loading, after the pretreatment of kerf were investigated. The results of this study were as the follows: The drying time of about 120 hours~130 hours was needed from green to about 15 percent of moisture content. The gradient of final moisture content for all specimens was very gentle in both longitudinal and transverse directions owing to dielectric heating. The surface checks seriously occurred although the occurrence extent of surface check for the kerfed specimens was slight compared with that for the control specimens because drying stress was relieved by kerf. The occurrence of surface checks for the L-specimen was more serious than that for the S-specimen.