• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.521-524
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• 2006

Recently, densified pollet fuel from wood biomass is widely used at North America and Europe as a regenerable and clean carbon neutral bioenergy. High-pressure compaction of sawdust of several species of wood to form a densified fuel was studied. Calorific and elemental analysis were carried out to assess pellet fuels Hot-press process was adopted for compact ion of sawdust and compaction was performed under prescribed condition. Densified fuels were evaluated by its oven-dry density and fines after 5-minute shaking test. The target density and fines of densified fuels were over $1.2g/cm^3$ and below 0.5%, respectively. When the press-temperature is over $60^{\circ}C$ densified fuels with density over $1.2g/cm^3$ and with fines below 0.5% can be produced. And the pressure over $1000kgf/cm^2$ was effect ive for this production.

• Journal of Biosystems Engineering
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• 제13권3호
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• pp.52-58
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• 1988

This study was conducted to develop a grain moisture content measurement sensor for automatic control of rough rice drying by natural air. For the above objective, the electrod type sensor was designed and tested. The sensor was able to produce electrical resistance which changes with moisture content of grain. An A/D converter and a micro-computer wed for processing measurement data of sensor. The developed sensor satisfied most design requirements and the results of statistical analysis show that there it no difference between the measurement method of sensor developed and of the dry-oven. Using the developed sensor and measurement system, we are able to measure moisture content of rough rice automatically in drying by natural air.

• 한국가구학회지
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• 제27권4호
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• pp.302-308
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• 2016

It has been known that acetylation improves the dimensional stability of wood. Liquid phase acetylation is more popular than gas-phase acetylation for the effectiveness of weight gain of wood. In this study the specimens of domestic red and Korean pines are acetylated in liquid phase and their physical properties, such as density, bending strength, anti-hygroscopicity etc., are analyzed. Acetylation increases the average weights and volume of larch specimens by 11.4% and 3.4%, respectively, and their average oven-dry densities are increased by $0.03g/cm^3$. Acetylation does not influence on Modulus of Rupture (MOR) and Modulus of Elasticity (MOE). The average Percentage Reduction in Hygroscopicity (PRH) and average Percentage Reduction in Water soaking (PRW) of larch specimens are respectively 20.2% and 20.8%. Thus it can be concluded that acetylation improves the dimensional stability of larch specimens.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.1318-1328
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• 1993

Expression of chinese cabbage was conducted in order to investigate its dewatering behavior. Chipped cabbage was packed into cylinder and pressed by piston up to the predetermined pressure on Instron-1000. The rates of dewatering were affected domintantly by the applied pressure, but not significantly by the packed amount of cabbage in the cylinder. The pressure effect was increased very abruptly at first, but the increase rate was very low at high pressure greater than 20 MPa, showing great deviation from linear dependence of flow rate on pressure in Darcy's Law. Therefore, water expression from cabbage was not Newtonian flow of water through cell wall. In fact, the squeezed water contained a lot of solid particles, showing destruction of cell wall. The content of solid particles in expressed water was only slightly lower than the dry matter content of fresh chinese cabbage, determined by drying oven method.

• 한국응용과학기술학회지
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• 제24권3호
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• pp.301-308
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• 2007

From the experiment result on pharmacetical characteristics and analysis of Garlic extract, some conclusions were obtained as follows. From the results on extract experiment of Garlic, extraction ratio was about 6.0%, and after dried with dry oven from Garlic extract, it obtained about 50%-Garlic extract of solid state. From results on antimicrobial experiment of Garlic extract, number of staphylococcus and fungus in microbe decreased more and more according to time passage. This phenomenon showed that Garlic extract keeps antimicrobial effect. From results on antioxidation experiment of Garlic extract, DPPH scavenging activity of free radical showed that Garlic extract appears more remarkable reduction ability than reference samples. This phenomenon means that antioxidation of Garlic extract appears higher than Vitamin-C and BHA. From results on instrument analysis, inorganic components of K, Na, Ca, Si, Mg, Zn etcs from Garlic extract were detected with ICP/OES and the fatty and aromatic components of trimethyl sulfide, diallyl disulfide, diallyl trisulfide, 2-mercaptobenzothiazole etcs from Garlic extract were detected with GC/MS.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.639-642
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• 2002

A new PDP barrier rib formation technique was investigated utilizing transparent soft maid made of silicon resin. Transparent soft mold was fabricated by pouring a silicone resin into the base mold made with photosensitive glass. The photosensitive barrier rib paste was coated on the glass substrate and dried in a 90 $^{\circ}C$ convection oven for 20min. The transparent soft mold was pressed on top of the semi-dry barrier rib layer and then irradiated with a UV lamp to a total dose of $900{\sim}1000mJ/cm^2$ The soft maid was then removed from the pressed barrier rib by winding up and fine pattern of barrier rib was obtained. The photosensitive barrier rib paste makes the demolding easy due to reduced interfacial forces and shrinking of paste materials.

• 펄프종이기술
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• 제29권1호
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• pp.13-25
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• 1997

To establish the weed control method without herbicide and weeding work, mulch paper was developed from domestic old corrugate container. Basis weight of mulch paper should be above 120 g/$m^2$ to guarantee the mechanical properties. It was concluded that polyamide polyamine epichlorohydrin was desirable to improve the wet strength of mulch paper and the optimum addition level was about 1.5% on the basis of oven dry pulp. The mulch paper was found to be effective in controlling paddy weeds. For the complete weed control the mulch paper should be sustained without decomposition over 45 days. As the paper mulching reduced the soil temperature, the mulch paper was required to improve the penetration of radiant heat.

• 펄프종이기술
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• 제43권2호
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• pp.24-30
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• 2011

The accelerated aging characteristics of electroconductive papers manufactured with a mixture of carbon fiber were investigated by heating in dry oven. By accelerated aging time, the tensile strength, tensile stretch of the papers were decreased more slowly with increase of carbon fiber content, but the electrical conductivity was more rapidly decreased in case of high carbon fiber content. The weight loss of papers by thermal analysis were reduced as increasing the carbon fiber content. These results were indicated that the electrical conductivity of carbon fiber was diminished easily by heat aging, but thermal characteristic of carbon fiber was much better than that of wood pulp.

• 한국가구학회지
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• 제13권1호
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• pp.19-25
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• 2002

Modern furniture is mostly made of panel products such as a glue-up panel, a particle board and a medium density fiberboard(MDF). Warping is a major defect of these panel products resulting in degrading final products. In this study the factors related to the warping of a glue-up panel and MDF were investigated by comparing the physical properties of warped specimens with those of the unwarped. The differences between the moisture contents measured on the both surfaces of specimens were found to mainly influence the warping of glue-up panel specimens whether conditioned or not. The average oven-dry density of warped glue-up panel specimens was definitely higher than that of the unwarped at l% significance level. For MDF the influencing factor on warping has not been revealed yet, however it was found that the conditioning reduced the number of warped specimens.

• 한국환경복원기술학회지
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• 제10권6호
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• pp.62-69
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• 2007

This study has been carried out to estimate aboveground carbon contents in an average 30-years-old Betula platyphylla and 32-years-old Juglans mandshurica stands in Chungju, Chungbuk Province. Nine sample trees were cut in each forest and soil samples were collected. Carbon concentration in stemwood, stembark, branch, and foliage were ranged from 54.6% to 57.0% in Betula platyphylla and 53.5% to 56.9% in Juglans mandshurica stands. Aboveground carbon contents was estimated by the equation model logWt=A+BlogD where Wt is oven-dry weight in kg and D is DBH in cm. Total aboveground carbon contents was 34.31t/ha in Betula platyphylla stand and 21.10t/ha in Juglans mandshurica stand. Aboveground net primary carbon production was estimated at 2.31t/ha/yr in Betula platyphylla stand and 2.03t/ha/yr in Juglans mandshurica stand.