• Journal of Plant Biology
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• v.17 no.3
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• pp.127-136
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• 1974

The effect of potassium metabolism on the soybean leaves was studied with comparison of other elements during the successive growing period. The results were as follows; 1. The percentage of potassium content showed remarkable increase not only in the first compound leaf at a stage which was growing vigorously and producing new leaves, but also in the fifth compound leaf at a stage which was taking a active metabolism of nitrogen and carbohydrate but not producing new leaves. However, the percentage of potassium content was decreased in the second compound leaf than in the first one. Such a result could be regarded as a potassium removal from mature leaves into immature and flowing out from stoma through respiration. During the pod-development the percentage of potassium content in the soybean leaf was decreased. 2. If nitrogen, phosphorus and potassium were added excessively in the nutrient solution, the percentage of potassium content in the soybean leaf had increased. The effects of these elements showed a remakable increase in the excessive plot of nitrogen than in that of phosphorus. At early stage the redtarded effect of phosphorus on the growth of soybean could be covered by potassium, however, at late stage it could not. The growth of soybean plant was much more inhibited by potassium, compared with nitrogen and phosphorus. New leaves could not be produced in the potassium deficient soybean plant after the third compound leaf. The normal growth of soybean plant could not be observed if only one element was excessively added to the culture solution, compared with the deficiency of other two elements.

• Journal of Korea Society of Digital Industry and Information Management
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• v.11 no.4
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• pp.81-87
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• 2015

Recently, with the development of the ICT environment, the use of the software is growing rapidly. And the number of the web server software used with a variety of users is also growing. However, There are also various damage cases increased due to a software security vulnerability as software usage is increasing. Especially web shell hacking which abuses software vulnerabilities accounts for a very high percentage. These web server environment damage can induce primary damage such like homepage modification for malware spreading and secondary damage such like privacy. Source code weaknesses checking system is needed during software development stage and operation stage in real-time to prevent software vulnerabilities. Also the system which can detect and determine web shell from checked code in real time is needed. Therefore, in this paper, we propose the system improving security for web server by detecting web shell attacks which are invisible to existing detection method such as Firewall, IDS/IPS, Web Firewall, Anti-Virus, etc. while satisfying existing secure coding guidelines from development stage to operation stage.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.3
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• pp.141-147
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• 2019

The purpose of this study was to determine the effect of waterlogging duration on the growth characteristics and productivity of forage corn at different growth stages under paddy field conditions. Treatments consisted of waterlogging at two growth stages (V7 or V14) for four waterlogging durations (no waterlogging, 48 hours, 72 hours, and 96 hours, respectively). The V14 growth stage was more vulnerable to waterlogging than the V7 stage. Among the waterlogging durations, the lodging score increased at 48 hours. The stem height of forage corn decreased with the increase in waterlogging duration at the different growth stages (V7 and V14). Increase in waterlogging duration reduced the stem dry matter yield, ear dry matter yield, and total dry matter yield at both growing stages (V7 and V14). The waterlogging treatments at the V14 stage affected ear dry matter yield more than those at the V7 growing stage. Thus, the management of forage corn under paddy field conditions must be strengthened during early (V7) and grain fill stages (V14). When waterlogging occurs, surface and subsurface drainage should be implemented within 48 hours to control (no waterlogging) the groundwater level and, thus, minimize economic losses due to forage corn damage.

• The Korean Journal of Ecology
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• v.15 no.1
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• pp.47-58
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• 1992

This study is to investigate the change of the seasonal patterns of relative water relations parameters by the pressure-volume curves in pinus koraiensis needles. The osmotic potentials at full water saturated(Ψ0, sat) and at incipient plasmolysis(Ψ0, tlp) increased in growing season, while decreased in non-growing season. The maximum bulk modulus of elasticity(Emax), relative water content(RWCTLP), and relativefree water content(FWCtlp) at incipient plasmolysis in non-growing season were higher than these of growing season. The maximum pressure potential(Ψp, max) varied from 1.16 to 2.18MPa, torgor index(TI) varied from 3.1 to 4.7. The osmole number(Ns/dw) and symplastic water (Vo/DW) were variable seasonally. The maximum water content(Vt/DW) and apoplastic water(AW) were relatively high in early growing stage, and then decreased to needle aging. The pressure potential(Ψp) and water potential(Ψ) in winter needles were rapidly decreased with decreasing of relative water content. The matric potential occupied over 10 percent of water potential with less than-2.0 MPa.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.2
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• pp.93-98
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• 1993

To determine the effects of potassium($K_2O$) fertilization level(0, 100, 200 and 300 kg/ha/year) on the growth, dry matter(DM) yield, nutritive value and nitrate nitrogen($NO_3$-N) concentration of grasses grown under shading condition, this experiment was carried out in Grassland Div., LES, 1989. The plants were sampled on different growing seasons (spring, summer and autumn) and growth stages (grazing and soiling), respectively. Shade was controlled artificially ca. 45-50%, and the level of nitrogen fertilization was 200 kg/ha/year in all treatments. Higher DM was produced in spring 1, 453 kg at grazing and 2, 364 kg/ha at soiling stage, and DM production was increased with increasing level of $K_2O$. In this experiment, the optimum amount of $K_2O$ fertilizer was 200 kg/ha. The neutral detergent fiber, acid detergent fiber, DM digestibility, and relative feed value of grasses were not affected by $K_2O$ fertilization, regardless of growing season and growth stage. The $NO_3$-N concentration of grasses grown in spring was very low (ca. 1.0%), regardless of growth stage and $K_2O$ level. However, $NO_3$-N concentration was very high in summer and autumn season, also $NO_3$-N was decreased significantly with increasing level of $K_2O$ fertilization (P<0.05). Application of $K_2O$ fertilizer, therefore, is thoughs to be desirable for reducing $NO_3$-N concentration of grasses, especially in summer and autumn season. So annual split fertilization of $K_2O$ could be recommended on woodland pasture.

• Korean Journal of Plant Resources
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• v.14 no.1
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• pp.48-52
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• 2001

The study was conducted to find effect of irrigation treatment during growth stage on growth and yield of Paeonia lactiflora Pallas L.. In case of top ground part, growth of irrigation treatment at early growing stage(from May 1 to June 12) was larger(stem length of 79.4cm) or thicker(stem diameter of 6.5mm) than stem length of 13.6∼7.4cm and stem diameter of 0.5mm of natural plot and control. The growth of under ground part, root length(34.0cm) and number of root/plant(43.6ea/plant) in irrigation treatment at early growing stage were relatively larger or more number than that of control, and root yield was gained 2,349kg/10a and increased 13% and 8% compare with natural plot and control, respectively. Commercial ratio of root was higher for irrigation treatment at early growing stage, it was increased by 20% than 1,708kg/10a of natural plot.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.4 no.1
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• pp.109-114
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• 1968

In order to investigate the growth pattern of sugar beet in Korea, this experiment was conducted using variety GW 359 at Tae-kwan-ryong, Suwon and Cheju. The results are summarized as follows; 1. At Tae-kwan-ryong, early growth stage was relatively long and during higher growing stage plants showed resistance to leaf spot disease, and vegetative maturing started from about September 15th. Top and root growth showed normal curve but it is considered that the early maturing variety will reduce the early growing period and prolong the vegetative maturing period. 2. At Suwon, the growth of top part was favorable until late of July but hereafter leaf spot disease brought death to the 25-35 leaves of top part and regenerated again in October. Consequently, sugar content of root showed changes from decrease to increase. Root weight increased from July to harvest season continunousely but showed abnormal growing curve. This indicates that Suwon is not proper place for sugar beet cultivation. 3. At Cheju, early growing stage was shorter about 15 days than that of Tae-kwan-ryong. Normal growth and long-maturing days favored the sugar accumulation in roots. But it is necessary to introduce non-bolting variety in autumn-winter season culture. 4. Sugar beet could be cultivated economically at Tae-kwan-ryong with 600-800 meter altitude for summer crop and at Cheju for winter crop, but Suwon is considered to be unfavorable for sugar beet.

• Applied Chemistry for Engineering
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• v.2 no.2
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• pp.97-107
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• 1991

Highly-siliceous dealuminated zeolite, silicalite(end member of ZSM-5) was synthesized from a batch composition of 2.55 $Na_2O-5.0$ TPABr-$100SiO_2-2800H_2O $ at $180^{\circ}C$ and at times ranging from one to seven days of reaction time. Autoclaves containing the synthesis mixture were centrifuged within the specially-equipped convection oven to provide an elevated gravitational force field like 30 and 50 G. Tests were also conducted at normal gravity. For synthesis performed under elevated gravities, average and maximum crystal sizes were substantially greater than those synthesized under normal gravity and product yields were also found to be affected by elevated gravity ; that is, product yields were substantially enhanced under elevated gravity from 4 % to 55 % with respect to normal gravity. The average crystal sizes of silicalite synthesized at normal gravity were 50 to $70{\mu}m$ over an entire range of reaction time, one to seven days while the average crystal sizes synthsized under elevated gravities, 30 and 50 G, were 160 to $190{\mu}m$ respectively. For the elevated gravity, in particular, two separate nucleations and growths were observed. For examples, at 50G, large crystals of $200{\mu}m$ were produced through the second growing stage after 5 days of reaction following the rapid first growing stage where fairly large crystals of $135{\mu}m$ were produced only in 2 days of reaction. The maximum crystal sizes obtained through the above two growing stages were 190 and $300{\mu}m$, respectively. A discussion of how elevated gravity affects nucleation, growth, yield and crystal size of silicalite is presented.

• Journal of Aquaculture
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• v.16 no.3
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• pp.179-186
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• 2003

Reproductive cycle, gonadal development and the spawning period of the Korean anchovy Coilia nasus were investigated by histologhical observations. Samples were collected at the coastal area of Geumgang dyke which is connected to Gunsan and Janghang, Korea, from February 2002 to January 2003. C. nasus is dioecious; the ovary consists of a pair of saccular structure with many ovarian lobules, and the testis consists of a pair of lobular structure with many testicular lobules and connected to the posterior seminal vesicle. Monthly changes in the gonadosomatic index (GSI) began to increase in April when seawater temperature increased and reached the maximum in June when the ovary was getting mature, the summer season of longer day length with higher water temperature. The reproductive cycle can be classified into five successive stage in females: early growing stage (February to March), late growing stage (March to April), mature stage (May to June), ripe and spent stage (June to July), and recovery and resting stage (July to January): in males, the cycle can be divided into four successive stages; growing stage (February to April), mature stage (May to July), ripe and spent (June to July), and recovery and resting stages (July to January). According to the frequency distributions of egg diameters in the spawning season. C. nasus is presumed to be summer spawning species and polycyclic species to spawn 2 times or more during the spawning season.

• Journal of Korean Society of Forest Science
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• v.9 no.1
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• pp.75-80
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• 1969

Traced observations were carried out for efficiency and behavior of Camellia japonica L in bloom stage by employing $p^{32}$-labeled phosphorus, growing in Southern Korea, and the results were as follows. 1) The percentage of phosphorus contained in flowerbud was double the value of the other parts, and the root and the stem were the same patterns in the course of the times. 2) The circulation of the phosphorus in the plant seems to occur within 24 hours, the proportions of the phosphorus at the growing-point and flowerbud had a half of the total phosphorus contained in other parts. 3) Specific activities of each part were notable on the growing-point where, after 24 hours it took more than 80 percent. On the other hand, the efficiency rate which derived from the phosphorus was shown as about 19 percents.