• Journal of Internet Computing and Services
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• v.23 no.5
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• pp.25-31
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• 2022

In ultra dense networks (UDNs), macro user equipments (MUEs) have significant interference from small-cell access points (SAPs) since a number of SAPs are deployed in the coverage of macro base stations of 5G mobile communication systems. In this paper, we propose a dynamic channel assignment scheme to increase the performance of MUEs for the uplink of UDNs even though the number of SAPs is increased. The target of the proposed dynamic channel assignment scheme is that the signal-to-interference and noise ratio (SINR) of MUEs is above a given SINR threshold assigning different subchannels to SUEs from those of MUEs. Simulation results show that the proposed dynamic channel assignment scheme outperforms others in terms of the mean MUE capacity even though the mean SUE capacity is decreased a little lower.

• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.58-65
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• 2002

This research was carried out to develop field treatment techniques of thinned small diameter softwood logs and less utilized hardwood logs using sap displacement method. In this paper, we report the feasibility of using transpiration method and butt-end method for the treatment of three softwood species and three hardwood species with preservatives, fire-retardant chemicals, and dimensional stabilizer. Butt-end method was effective as a field treatment technique compared to transpiration method when considered the treatability, easiness of treatment, productivity of treated wood, and environmental aspects related to chemical treatment, regardless of the combination of wood species and chemicals.

• Journal of Korean Society of Forest Science
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• v.85 no.2
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• pp.288-299
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• 1996

This is the basic study to investigate the amount of transpirational water loss in thrifty mature Quercus mongolica stand by the heat pulse method. The differences of heat pulse velocity by direction and depth, differences of heat pulse velocity by dominant, codominant and suppressed trees, diurnal changes of heat pulse velocity due to the change of leaf water potential, vapor pressure deficit and radiation, and sap flow path way in sapwood by dye penetration were measured in stems. Finally the amounts of daily and annual transpiration in stand were calculated by the heat pulse velocity. The results obtained were summarized as follows : 1. Relationship between heat pulse velocity(V) and sap flow rate(SFR) was obtained as a equation of SFR=1.37V. 2. The sap flow rate was high in the order of dominant, codominant, and suppressed trees. The daily heat pulse velocity changed with radiation, temperature and vapor pressure deficit. 3. The heat pulse velocity showed the similar diurnal variation as the leaf water potential change. 4. The heat pulse velocity showed the highest value in May(4.0cm/hr in average), the lowest one in July(2.9cm/hr in average). 5. The heat pulse velocity in the same stem presented the highest value in the northern direction, medium in western, and the lowest in southern and eastern. 6. The heat pulse velocity in stem was highest in 0.5cm, medium in 1.0cm, and lowest in 1.5cm depth from the surface of stem. 7. The sap flow path way in stem showed sectorial straight ascent pattern in four sample trees. 8. The amount of sap flow(SF) was presented as a equation of $SF=1.37A{\cdot}V$(A: the cross-sectional area of sapwood, V: heat pulse velocity), and especially SF was larger in dominant tree than codominant and suppressed trees. 9. The amount of daily transpiration was 5.6ton/ha/day, and its composition ratio was 72% at day and 28% at night. 10. The amount of stand transpiration per month was largest in May(168ton/ha/month), lowest in July(125ton/ha/month). The amount of stand transpiration per year was 839ton/ha/year.

• Current Research on Agriculture and Life Sciences
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• v.5
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• pp.89-99
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• 1987

The changes of lipid components in apple peels which effects physiological characteristic in apple storage, and pigment which is important base in quality, were investigated in terms of temperature and pressure. The results obtained were as follows ; The contents of total lipid of Ralls which is resistant to cold temperature were higher than those of Fuji. The contents of total lipid of Fuji and Ralls were decreased up to about 60 days and then increased up to the final stage of storage. Especially, the increasing rate at low temperature storage was greater than at normal temperature storage. In the case of Fuji, the contents of neutral lipid of normal temperature were increased up to 90 days, while those of low temperature were decreased up to 60 days and then increased up to 90 days. The contents of glycolipid, in both Fuji and Ralls were decreased up to about 30 days and then increased up to about 60 days and the decreased up to 90 days. The contents of phospholipid in Fuji were decreased during storage, while those in Ralls were appeared very slight changes. The ratios of unsaturated fatty acid to saturated fatty acids in neutral lipid of Fuji were decreased during storage, but those of Ralls were increased. Those of glycolipid of Fuji were decreased up to 60 days and then increased up to 90 days, while those in Ralls were increased during storage. In both Fuji and Ralls, those of phospholipid increased during storage and were high in order of sub-atmospheric pressure at $1^{\circ}C$ (SAP-L), normal atmospheric pressure at $1^{\circ}C$ (NAP-L), sub-atmospheric pressure at $20^{\circ}C$ (SAP-N) and normal atmospheric pressure at $20^{\circ}C$(NAP-N) for storage condition. The contents of chlorophyll of Ralls were higher than those of Fuji and the decreasing rate was the lowest in SAP-L. The changes of carotenoid and anthocyanin contents were the greatest increasing at NAP-N and colouring was delayed at SAP-L.

• Journal of Plant Biology
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• v.36 no.4
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• pp.363-370
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• 1993

Experiments with non-nodulated alfalfa (Medicago sativa L. cv, Europe) plants grown in hydroponic cuiture, were carried out to estimate the remobiJization of nitrogen (N) reserves and to investigate the transported forms of reduced soluble-N in xylem during regrowth following shoot removal. Endogenous N remobilization were estimated by $^{15}N$ labelling and amino acids in xylem sap were analysed. The, $^{15}N$ contents of ~egr9wing leaves and stems increased as a result of remobilization of N reserves mainly from root ,system, Regrowing leaves were a stronger sink than regrowing stems, with about tWo-thirds of remobilized 15N being recoved in leaves. Endogenous N in lateral roots accounted for about 46% of the total N reserves used for regrowth, while tap roots accounted for 23%, About 72% of total endogenous N remobilized to regrowing shoot, occurred during the first 10 days of regrowth, The outflow of reduced soluble-N (mainly amino acids) was greater than that of protein-N, while the latter was the largest storage pool in tap root and lateral roots. It is suggested that amino acids-N was the most readily avaiable form of N reserves. Asparagine, which repre5ented about 75% of amino acids-N in xylem sap, was the main transported form of reduced N. Its relative contents, during the first 10 days of regrowth, decreased from 75% to 59%. This decline was accompanied by compensatory increase in the relative contents of asparatate and glutamine.

• Journal of Bio-Environment Control
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• v.7 no.3
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• pp.206-213
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• 1998

This experiment was conducted to investigate the effects of concentration of NO$_{3}$$^{[-10]}$ , $K^{＋}$ and $Ca^{＋＋}$ in nutrient solution on the seedlings growth of ‘Mudeungsan’watermelon. Seeds were sown on March 16, 1997. NO$_{3}$$^{[-10]}$ , $K^{＋}$ and $Ca^{＋＋}$ was treated with three different levels, respectively, NO$_{3}$$^{[-10]}$ = 106, 206, 406ppm; $K^{＋}$ = 150, 200, 400 ppm; $Ca^{＋＋}$ = 150, 200, 400 ppm. Plant growth was investigated at four-days interval in 10 days after treatment. Increasing N concentration in the nutrient solution increased the plant height, leaf area, number of leaves, fresh and dry weight of shoot while high concentration of K and Ca in the nutrient solution decreased the seedling growth in terms of leaf area, leaf dry weight. The uptake of N, K and Mg in petiole sap was positively affected by the adding of 206 ppm of nitrate, 150 ppm of potassium and 200 ppm of calcium levels, respectively. The P and Ca uptake in petiole sap was not affected by the N and K concentrations in the nutrient solution while K concentration above 200 ppm decreased the N and Mg content in petiole sap. High concentration of Ca in the nutrient solution increased the Ca content in petiole sap while Ca concentration above 200 ppm decreased the N content.

• Journal of Bio-Environment Control
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• v.17 no.3
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• pp.238-245
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• 2008

This study was carried out to investigate the effect of magnesium (Mg) concentrations in nutrient solution on growth of and nutrient uptake by 'Maehyang' strawberry. Tissue analysis based on dry weight and petiole sap were also conducted to determine the threshold level in plants when Mg deficiency disorders developed in strawberry plants. In the Mg deficient plants, the spotted yellowing or yellowing area developed on the interveinal area of mature leaves. The dark brown color also developed on the interveinal area of mature leaves with marginal browning or marginal necrosis. The response in dry weight production of 'Maehyang' strawberry to elevated Mg concentrations in nutrient solution was quadratic and the equation is y=6.84+1.7533x-$0.9278x^2$ $(R^2=0.1081^{***})$. But the Mg contents in tissue increased lineally with the equation of y=0.1764+0.1275x $(R^2=0.8307^{***})$. The trends of fresh weight production and Mg concentrations in petiole sap were also quadratic (y=24.127+7.3565x-$1.125x^2$, $R^2=0.2314^{^***}$) and linear (11.954+5.793x, $R^2=0.6869^{***}$), respectively. To prevent growth suppression, the Mg concentrations based on dry weight of above ground tissue and in petiole sap should be in the range of 0.30 to 0.65% and 19 to $40mg{\cdot}kg^{-1}$, respectively, fer the commercial production of 'Maehyang' strawberry.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.10
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• pp.1482-1487
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• 2011

This study evaluated the physicochemical characteristics and nutritional components of Goroshoe (Ace rmono Max.) sap related with collection periods. The changes of browning index, turbidity, pH, total acidity, organic acids, free sugar, crude protein, crude ash, and minerals were investigated. Browning index and turbidity were slightly increased, while pH and total acidity were not changed as collection periods increased. Citric acid decreased slightly from 0.081 to 0.045 mg/mL at middle collection periods. Malic acid also decreased from 0.494 to 0.416 mg/mL at middle collection periods but then afterward increased to 0.674 mg/mL as collection periods increased. Sucrose decreased from 1.759 to 1.000%, while fructose increased from 0.023 to 0.044% as collection periods increased. Crude protein increased remarkably from 0.80 to 17.49 mg% as collection periods increased. Crude ash decreased slightly from 0.04 to 0.03% at middle collection periods, and then increased afterward to 0.06% as collection periods increased. Potassium increased from 13.43 to 49.75 mg/L as collection periods increased. These results indicate that the useful components of Goroshoe sap increased with increasing collection periods, but turbidity could be reduced.

• Applied Biological Chemistry
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• v.46 no.2
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• pp.140-143
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• 2003

This study was performed to develop a more rapid and simple nutrient diagnosis method of plants than the conventional leaf analysis method. tomato (Lycopersicon esculentum Mill. cv. super momotaro) was planted in the mixed media produced by mixing perlite and rock wool at 1 . 1 (v/v) ratio. The Yamazakki nutrient solutions for cucumber and tomato were supplied to the media using the micro-drip irrigation system. Experimental plots produced consisted of no fertilization, deficient fertilization, adequate fertilization and surplus fertilization for N, P and K, respectively. Each experimental plot was replicated four times. Specific color different sensor values (SCDSV) measured by the chlorophyll meter were closely related to total-N concentrations in the leaves measured by the conventional method. Nitrate, $PO_4$ and K concentrations in petiole sap measured by test strips #(Reflectoquant^{\circledR},\;Merck,\;Germany)$ showed a significant relationship with total-N, p and K concentrations in leaves. The linear regression equations between $NO_3,\;PO_4$ and K concentrations in petiole sap and total-N, p and K concentrations in the leaves were prepared. The optimum levels of $NO_3,\;PO_4$ and K in petiole sap were obtained by plugging the optimum concentrations of total-N, p and K in the leaves by other researchers into the equations. In conclusion, the SCDSV by the chlorophyll meter and concentrations of NO3, p and K in petiole sap measured by the test strips would be suitable for rapid estimation of plant nutrient status.

• Journal of Life Science
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• v.27 no.5
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• pp.561-566
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• 2017

Dendropanax morbifera Lev. is known in Korea for its golden sap and medicinal properties. The many biological activities of the leaf and stem extracts suggest that this tree could be a valuable source of medicinal compounds for the treatment of various ailments such as dermatitis, migraines, dysmenorrhea, muscle pain, and infectious diseases. However, there is little information on the composition and biological activity of the volatile fraction of D. morbifera. Therefore, in this study, the volatile compounds in leaves, stems, and sap of D. morbifera were isolated using solvent and supercritical fluid extraction (SFE), and analyzed by gas chromatography/mass spectrometry to reveal their chemical composition and identify potential compounds of interest. Fifteen compounds were identified in the leaf extracts, whereas 29 and 3 compounds were identified in the stem and sap extracts, respectively. The volatile profiles obtained using solvent and SFE differed. Esters and aromatic hydrocarbons predominated in the solvent extract of leaves and SFE extract of stems, whereas the solvent extract of stems and SFE extract of leaves contained terpenoids. Limonene, ${\alpha}$-pinene, and ${\beta}$-myrcene were identified in the volatile extract of sap, with limonene representing 96.30% of the total peak area. In addition, the antiproliferative effects of the solvent extracts of leaves and stems were evaluated, revealing that these solvent extracts were particularly effective in decreasing the proliferation of HepG2 cells.