• Journal of the Korean Wood Science and Technology
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• v.44 no.3
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• pp.302-314
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• 2016

This study was carried out to confirm the effects of the knife-incising and kerfing pretreatment on the moisture content and surface check occurrence of Douglas-fir heavy timber. In the case of moisture content, the moisture gradient that formed in the inner part of the specimen was observed in all specimens. In addition, the moisture gradient was formed differently from the surface layer to 72 mm depending on the pretreatment conditions, and it was formed gradually in the kerfing than the knife-incising. In addition, it was found that the solid volume should be considered when measuring the average moisture content. In the case of surface check, the surface check occurrence was reduced in the knife-incising, kerfing, and the combination of knife-incising and kerfing than the control. In particular, the kerfing treatment was shown that the expansion of surface check width was effectively suppressed. In the case of knife-incising treatment, although the surface check was less than the control, the preventive effect on the surface check occurrence did not reach the level of the kerfing treatment.

• Journal of Korean Medicine Rehabilitation
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• v.24 no.3
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• pp.29-37
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• 2014

Objectives Osteoporosis is an impending problem in the rapidly aging society. The purpose of this study is to identify the effects of Yoohyangheukho-dan ($R{\check{u}}xi{\bar{a}}ngh{\bar{e}}ih{\check{u}}-d{\bar{a}}n$) on osteoporosis induced by ovariectomy in rats. Methods 24 rats were randomly assigned to a SHAM group, a control group, and a Yoohyangheukho-dan ($R{\check{u}}xi{\bar{a}}ngh{\bar{e}}ih{\check{u}}-d{\bar{a}}n$) group (n=8). Ovaries were extracted and for 8 weeks, the rats were given dry feeds and Yoohyangheukho-dan ($R{\check{u}}xi{\bar{a}}ngh{\bar{e}}ih{\check{u}}-d{\bar{a}}n$) group were given a mixture of dry feeds and Yoohyangheukho-dan ($R{\check{u}}xi{\bar{a}}ngh{\bar{e}}ih{\check{u}}-d{\bar{a}}n$). At 8 weeks, their body weight, femur mass, tibia ash per body ratio, overall surface area and thickness of the trabeculae, overall surface area of the osteoblasts, and the number of osteoclasts were measured and levels of albumin, aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), total-cholesterol, calcium and estradiol were recorded. Results There was no significant difference in the weight of the femur and the tibia ash per body ratio. The Yoohyangheukho-dan ($R{\check{u}}xi{\bar{a}}ngh{\bar{e}}ih{\check{u}}-d{\bar{a}}n$) group had significantly thicker trabeculae than the control group and showed a minimal increase of overall surface area of the trabeculae. The overall surface area of the osteoblasts and the number of osteoclasts decreased in the Yoohyangheukho-dan ($R{\check{u}}xi{\bar{a}}ngh{\bar{e}}ih{\check{u}}-d{\bar{a}}n$) group. There were no statistically significant differences in AST, ALT, ALP, total cholesterol, phosphorus, and estradiol levels. On the contrary the Yoohyangheukho-dan ($R{\check{u}}xi{\bar{a}}ngh{\bar{e}}ih{\check{u}}-d{\bar{a}}n$) group had significantly higher levels of Albumin, triglyceride, and calcium. Conclusions It can be concluded that oral intake of Yoohyangheukho-dan ($R{\check{u}}xi{\bar{a}}ngh{\bar{e}}ih{\check{u}}-d{\bar{a}}n$) prevents the thinning process of the trabeculae. Thus, it may have positive effects on the treatment and prevention of osteoporosis in postmenopausal women.

• Transactions of Materials Processing
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• v.7 no.1
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• pp.66-71
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• 1998

The present study is concerned with the hydrostatic extrusion process of copper-clad aluminium bar to investigate the bonding conditions as well as the basic flow characteristics. Considering the bonding mechanism of bi-metal contact surface as cold pressure welding the normal pressure and the contact surface expansion are selected as process parameters governing the bonding conditions, in this study the critical normal pressure required for the local extrusion-the protrusion of virgin surfaces by the surface expansion at the interface-is obtained using a slip line method and is then used as a criteron for the bonding. A rigid plastic finite element method is used to analyze the steady state extrusion process. The interface profile of bi-metal rod is predicted by tracking the paths of two particles adja-process. The interface profile of bi-metal rod is predicted by tracking the paths of two particles adja-cent to interface surface. The contact surface area ration and the normal pressure along the interface are calculated and compared to the critical normal pressure to check bonding. It is found that the model predictions are generally in good agreement with the experimental observations. The compar-isons of the extrusion pressure and interface profile by the finite element with those by experi-ments are also given.

• Korean Journal of Breeding Science
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• v.49 no.3
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• pp.230-234
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• 2017

A mungbean variety 'Suhyeon' (Vigna radiata (L.) Wilczek) was derived from the cross between 'Jeonnam14' and 'IT208777' at the Jeollanamdo Agricultural Research and Extension Services (JARES) in 2010. 'Suhyeon' has erect growth habit, heart leaflet, green hypocotyl, black and straight pod when matured, and dull green seed surface. The stem length of 'Suhyeon' was 66 cm, which was 5 cm less than check variety 'Owool'. The pods number per plant of 'Suhyeon' was 24, which was 5 more than check variety. The sprout yield ratio of 'Suhyeon' was 8.67 times, which was 16% more than check variety. The contents of starch, protein and fatty acid of seed were 62.7, 27.3, 1.89%, respectively. The average yield of 'Suhyeon' was 1.74 ton/㏊, which increased 8% more than that of check variety. (Variety registration number: 5107)

• Journal of the Korean Society of Environmental Restoration Technology
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• v.1 no.1
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• pp.63-69
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• 1998

The slope revegetation methods in Korea are generally the hydroseeding mixed with perennial herbs, soil, fibers, and fertilizer in consideration of scenic landscape rather than ecological and engineering effect. But perennial herbs can't protect the slope from deep surface erosion and they are not tall enough to create the original naturalness at the boundary parts of existing woodlands. This study is about the slope revegetation method using nutritional propagation capacity of plants and the experimental construction was carried out on the cut-slope of Yongin Hoam C.C. We dug several trenches to a depth of 80cm and at intervals of 150cm from each other. After placing various kinds of live branches(Salix species) into the trench, we backfilled with the excavated soils and finally sprayed water mixed with soil-stabilizer, fertilizer. As six months passed, we made a vegetation research and check the slope surface erosion. Vegetation research was performed in examining the frequency of each block using transect method. 31 kinds of plant species appeared in total area($113.6m^2$) and the dominant species are Setaria viridis, Artemisia rubripes, Persicaria pubescens, Plantago asiatica, Cyperus amuricus, Commelina communis. Among the examined blocks, '아', the top part of the slope, showed the ratio of 1.4 as the highest Alpha-diversity. With regard to life form, therophytes were shown dominant distribution of 58% of total species and neophytes relatively low distribution of 16%. It can be estimated that there is no ecological stabilization of this slope, because of ruderal species' occupation of 74% in total area. Regarding the slope stabilization, the serious surface erosion didn't take place in spite of heavy rainfall this year, but a little surface erosion took place at the block where no other species coming from outside of the site were found.

• Journal of the Optical Society of Korea
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• v.18 no.5
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• pp.569-573
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• 2014

We demonstrate a low-cost, superbly efficient way of etching for the nano-, and micro-sized pyramid patterns on (100)-oriented Si wafer surfaces for use as a patterned master. We show a way of producing functional optical films for the viewing angle direction brightness-enhancement of Lambertian LED (light emitting diode)/OLED (organic light emitting diode) planar lighting applications. An optimally formulated KOH (Potassium hydroxide) wet etching process enabled random-positioned, and random size-distributed (within a certain size range) pyramid patterns to be developed over the entire (100) silicon wafer substrates up to 8" and a simple replication process of master patterns onto the PC (poly-carbonate) and PMMA (poly-methyl methacrylate) films were performed. Haze ratio values were measured for several film samples exhibiting excellent values over 90% suitable for LED/OLED lighting purposes. Brightness was also improved by 13~14% toward the viewing angle direction. Computational simulations using LightTools$^{TM}$ were also carried out and turned out to be in strong agreement with experimental data. Finally, we could check the feasibility of fabricating low-cost, large area, high performance optical films for commercialization.

• Applied Chemistry for Engineering
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• v.20 no.3
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• pp.241-250
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• 2009

During the past few years, titanium salts were investigated as alternative coagulants for the removal of organic matter of different molecular sizes in contaminated water. The flocculation efficiency of Ti-salt was comparable to those of $FeCl_3$ and $Al_2(SO_4)_3$ salts, commonly used coagulants. Incinerated sludge-$TiO_2$ showed higher surface area and photocatalytic activity than commercially available $TiO_2$. Metal-doped forms were produced by adding coagulant aids such as iron (Fe-), aluminium (Al-) and (Ca-) calcium salts during Ti-salt flocculation to increase pH. Ca- and Al- doped $TiO_2$ showed very high photocatalytic activity compared to Fe-doped $TiO_2$. When tested in a pilot scale plant for treatment of dye wastewater to check practical feasibility of the novel process, the removal ratio of the chemical oxygen demand was comparable to those of commonly used coagulants but the settling of sludge was faster. The $TiO_2$ generated after sludge incineration showed a high photocatalytic activity for degradation of volatile organic compounds and increased the rate of hydrogen production by water photosplitting. $TiCl_4$ coagulant and $TiO_2$ produced from different water sources with different concentrations had low acute toxicity compared to heavy metals and commercial $TiO_2$ when examined based on D. Magna mortality. This paper presents the production, characterisation and the photoactivity of $TiO_2$ produced from Ti-salt flocculated sludge. Different case studies are discussed to highlighted recent advances in this field.