• Journal of the Korean Wood Science and Technology
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• 제39권1호
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• pp.1-7
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• 2011

Recently, the visual grading rule of Korea Forest Research Institute (KFRI) was revised and it is necessary to investigate the distribution characteristics of visual graded lumber in accordance with the revised rule. Therefore, in this study, the distribution characteristics of bending strength was investigated with revised visual grading rule and changed prior rule, respectively. The size of specimens was $38{\times}140{\times}3,000$ (mm) and the species were $Larix$ $kaempferi$ and $Pinus$ $koraiensis$. The moisture content was under 18% and the specimens were tested in accordance with ASTM D-198. The number of No. 1 and 2 grades, suitable for structural lumber, was increased when the revised visual grading rule was applied. Moreover, the revised rule was more effective to distinguish sharply between No. 1 and 2 grades and below No. 3 grade. Meanwhile, the lower 5% exclusion limit and allowable stresses were generally decreased when revised visual grading rule had been applied. However, the announcement of Korea Forest Service, tested with small clear specimen, was much lower than the allowable stresses of this test, tested with structural lumber. Therefore, the revision of allowable design values should be considered for more exact use and effective structural design.

• Journal of Korean Society of Forest Science
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• 제77권2호
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• pp.193-198
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• 1988

This study was carried out to investigate the influence of shading pretreatment and planting density on the periodic needle leaves growth in fresh and dry weight. 1. The fresh and dry weight growth of needle leaves per seedlings increased with light intensity and decreased with increase of density. The best growth of needle leaves in fresh weight and dry weight appeared during the period from May to June. 2. The contribution rates to the growth of fresh and dry weight of needle leaves were 1.9% and 5.1% in light intensity, 3.6% and 3.2% in density and 83.7% and 75.6% in growth period, respectively. 3. For the three factors, shading, density and growth period, all the interactions between any two factors, and among the three factors in the fresh and dry weight growth of leaves per plant were significant.

• Asian-Australasian Journal of Animal Sciences
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• 제29권12호
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• pp.1734-1741
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• 2016

This study was conducted to examine the effects of adding phytoncide oil extracted from Korean pine nut cone by-product to the diet of dairy cows on milk yield and compositions, fatty acid characteristics, complete blood count and stress response. A total of 74 Holstein cows were used for 30 days and divided into two groups. Each group was given a basal diet (C) or an experimental diet containing phytoncide additives at 0.016% (T) in feed. The results showed that phytoncide feeding had no effect on milk yield. In addition, there were no observed effects on milk composition, but the ratio of fatty acid in milk was significantly affected by the phytoncide diet, and it showed a positive effect. Not only were the major functional fatty acids, conjugated linoleic acid and eicosapentaenoic acid increased, but also ${\omega}6:{\omega}3$ fatty acid ratio was reduced in milk of T group (p<0.05). In blood analysis, the complete blood count showed no significant difference between C and T group on all parameters. However, the cortisol concentration was significantly decreased in T group compared to control (p<0.05). Taken together, we suggest that phytoncide oil does not have a great influence on the physiological changes, but can be a potential feed additive that improves the milk fatty acid and stress resilience in dairy cows. In addition, it will contribute to the development of feed resource, a reduction in feed cost and a lessening of environmental pollution.

• Asian-Australasian Journal of Animal Sciences
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• 제33권1호
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• pp.111-119
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• 2020

Objective: This study was conducted to examine the effects of a mixture of pinecone oil, garlic, and brown seaweed extracts (PGBE) on milk production traits as well as physiological and ethological parameters in Holstein cows during the summer season (24 May to 03 July 2015, Korea). Methods: Among the extract combinations tested, we found that the level of 2,2'-azino-bis (3-ethylberzothiazoline-6-sulphonic acid) cation radical scavenging activity of the 0.16% PBGE complex at ratio of 1:1:1 (vol/vol) was comparable to that of the control (ascorbic acid; 1 mg/mL). Additionally, the PBGE complex reduced lipopolysaccharide-induced COX-2 expression in bovine mammary epithelial cells. Based on these findings, 40 lactating Holstein cows were used to measure the effects of PBGE complex at ratio of 1:1:1 (vol/vol) on milk production, immune response, metabolites, and behavior patterns by dividing the cows into two groups fed diets containing PGBE complex (n = 20; 0.016%/kg feed dry matter basis) or not containing PGBE complex (control, n = 20) for 40 d. Results: Results showed that PGBE complex did not influence milk composition, eating and ear surface temperature patterns, immune response, or metabolic parameters but promoted average milk yield throughout the experimental period. Additionally, a tendency of higher total antioxidant capacity and glutathione in the PGBE group was observed compared to the those in the control. When the temperature-humidity index (THI) exceeded 72 (average THI = 73.8), PGBE complex-fed cows experiencing heat stress showed increased milk yield and a tendency of increased rumination compared to the control. Conclusion: We suggest that incorporation of a combined mixture of 0.016% PGBE (1:1:1 ratio, vol/vol) to diet has the potential to improve milk yield and health status of cows under mild to moderate heat stress, denoting that it might be useful as an alternative anti-stressor in the diet of dairy cows under hot conditions.

• Journal of Korean Society of Forest Science
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• 제88권4호
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• pp.523-532
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• 1999

The studies were carried out to develop an urban forest aromatic bath in the idle space within city area for handicapped persons, patients and city workers, who having less chance to visit the natural forest aromatic bath. The environmental conditions were checked in the experimental double vinyl house where native and exotic aromatic woody and herbaceous plants were growing with minimum energy input in the periods of mid-winter and mid-summer. The growth and photoperiodic responses of the plants to the low and high temperatures were observed during winter and summer respectively. The most of herbaceous plants in the double vinyl house with the controlled minimum night temperature of $-2^{\circ}C$ had no winter injury but did not grow and started the growth in April. The exotic herbs such as Catnip faassen's(Nepeta x faassenia) and Lemon bergamot(Monarda citriodora) grew better in the longer photoperiodic conditions. The growth rates of Abies koreana, Thuja koraiensis and Pinus sylvestriformis in the early spring were affected mainly by the night minimum temperature and less affected by the photoperiodic conditions during winter. The native aromatic herbs such as Robdosia japonica, Molsa punctulata, Agastache rugosa and Codonopsis lanceolata showed stimulatory growth at the 16 hours day-length in case of the high temperature vinyl hose. The height and root collar diameter growth of pine seedlings were inhibited in maxim temperatures over $40^{\circ}C$ during summer.

• Journal of Korean Society of Forest Science
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• 제83권4호
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• pp.450-459
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• 1994

The damage by the black-tipped sawfly, Acantholyda posticalis posticalis Matsumura, has been increasing at several locations in central part of the Korean peninsula. This study was undertaken at selected plots in Kapyung-gun, Kyunggi Province and Hongchon-gun, Kangwon Province from 1984 to 1987. The purpose of this study was to provide basic information for integrated control of this pest and to determine the economic threshold by investigating the pest host interactions with special reference to damage analysis. The results obtained were as follows ; 1. The damage was more severe at upper part than at lower part of the crown. The vertical distribution of dry weight of damaged trees above ground showed L-type distribution, whereas that of healthy trees showed C-type distribution. 2. The needle loss by sawfly reduced both of height and the diameter growth of the main stem. The growth reduction occurs when the needle loss is 50% or higher. About 10% of tree growth was reduced at 50% of needle loss. 3. The reduction of diameter growth was more severe at upper part than at lower part of the main stem. 4. Volume growth was reduced when more than 50% of the needles were damaged after three years of the sawfly infestation. Reductions of total volume increment at the levels 70% and 90% of needle damage were 9% and 20%, respectively.

• Journal of Korean Society of Forest Science
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• 제83권4호
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• pp.498-504
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• 1994

The damage by the black-tipped sawfly, Acantholyda posticalis posticalis Matsumura, has been incheasing at several locations in central part of the Korean peninsula. This study was undertaken at selected plots in locality of Kapyung-gun. Kyunggi Province from 1984 through 1987. The purpose of this study was to provide basic information for integrated control of this pest and to determine the economic threshold by investigating the pest-host interactions with special reference to damage analysis. The results obtained were as follows ; 1. One year old cone formation began to be reduced when 30-40% of the needles were destroyed. With 70% of defoliation, few cones were produced. 2. Number of two year old cone formation and amount of cones began to be reduced when 61-70% of the needles were destroyed ; economic threshold of the defoliation rate retarding the seed production was 51%. 3. Growth of the trees was significantly reduced when more than 50% of the needles were destroyed, and cone production began to be retarded at 30-40% of defoliation. Therefore, it was determined that the economic thresholds requiring the control practices to keep normal tree growth and cone production from being reduced were 50% and 30%, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• 제13권4호
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• pp.406-412
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• 1984

Total lipids (TL) from Korean pinenut (Pinuskoraiensis S & Z) were extracted, purified and fractionated into three lipid classes (neutral lipid: NL, glycolipid; GL, phospholipid; PL). Lipid contents(constituent components) and fatty acid composition of three lipid classes were determined by thin layer chromatography and gas chromatography. TL ranged from 69.0% to 69.8% in fresh pinenut and consisted of 95.9% to 96.7% NL, 3.2% to2.5% GL and 0.9% to 0.8% PL. In the NL, triglycerides were predominant (80.8%) with the smaller amounts of sterol, diglycerides, free fatty acids, sterol esters and hydrocarbons. Monogalactosyl diglycerides and esterified steryl glycosides (23.5%) were the major components of GL, but cerebrosides, steryl glycosides and digalactosyl diglycerides were also found as minor components. Of the PL, phosphatidyl choline (40.2%) and phosphatidyl ethanolamine (19.4%) were the major components, comprising over 60% of this class. Phosphatidyl inositol, lysophosphatidyl choline were also present in the PL. The major fatty acids in the NL were linoleic acid (48.6%), oleic acid (28.8%) and arachidic acid(14.4%), The fatty acid composition in the GL was similar to the pattern in the NL, but PL contained a higher percentage of palmitic acid (17.7%) and stearic acid (6.0%) than other lipid classes.

• Journal of the Korean Wood Science and Technology
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• 제42권6호
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• pp.666-674
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• 2014

In this study, we investigated mechanical properties of Korean softwoods after applying thermal compression. Density of compressed woods was notably increased with thermal compression. In case of 50% compression set, density of Korean pine (Pinus koraiensis), Japanese red pine (P. densiflora), and Larch (Larix kaempferi) wood was increased by 71%, 74%, and 76%, respectively, when compared to the control group. The strength of woods was increased and quality of the woods became homogeneous with an increases in the compression set. On the 50% compression set, the compressive strength, bending strength, and hardness of Korean pine wood was increased by 76%, 83%, and 55%, respectively compared to the control group. Longitudinal compressive strengths of Japanese red pine wood increased by 69%, 130%, and 76%, respectively and those of Larch wood increased by 77%, 120%, and 44%, respectively. In thermal compression wood, mechanical properties of Larch wood was the highest, while those of Korean pine wood were the lowest. However, Japanese red pine wood showed the highest in the increase rate of mechanical properties after the thermal compression.

• Korean Journal of Agricultural and Forest Meteorology
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• 제3권2호
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• pp.88-95
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• 2001

This study was conducted to investigate vertical movement properties of water quality or chemical composition in three different forest stands (Pinus koraiensis, Larix leptolepis and Quercus spp. stands) in Gwangju-gun and Gyunggi-do. The results were as follows ; The pH range of precipitation was 4.62 ~ 6.72, and the average pH showed 5.74. The relationship of pH among throughfall, stemflow and precipitation showed difference of buffering capacity in tree species. According tree species, acided stemflow and alkalized stemflow had the characteristic value. In three stands, changes of the pH in early rain were larger than those of succeeding rain, except October 1998 and April 1999. Early rain influenced the cation in the acidity and concentration, but succeeding rain influenced the anion such as S $O_{4}$$^{2-}$, N $O_{3}$$^{[-10]}$ , C $l^{[-10]}$ etc. And anion components exist with gas type and minute particles, as a result, succeeding rain influenced to chemical properties by the sustaining washout.