• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.33A no.6
• /
• pp.189-196
• /
• 1996

We have studied sngle-frequency yield of 1.55${\mu}$m DFB lasers with uniform sinusoidal grating using an effective index transfer matrix method considering both threshold gain difference and spatial hole-burning effect. Optimum grating height and mirror reflectivities that maximize the single-frequency yield are found for a low-reflection (LR)/high-reflection(HR) mirror structure and a LR/as-cleaved miror structure for an assumed basic waveguide structure. LR/HR structure has a high yield of about 80% in a narrow range of grating height while LR/as-cleaved mirror structure has a low yield of about 50% in a relatively wide range of grating height. The effect of the low-reflection facet reflectivity is also studied.

• Plant Resources
• /
• v.4 no.2
• /
• pp.97-101
• /
• 2001

This study was carried out to determine the effect of sowing time on the flowering, growth and yield of Schizonepeta tenuifolia Briquet. Emergence and flowering dates in the sowing time from March 30 to April 30 were earlier than those of the other sowing times. In the sowing time from March 30 to April 30, length and diameter of main stem, number of node per main stem, number of branch per plant and fresh, and dry weight of stem were greater than those of the other sowing times. Yield components such as ear length, main stem length and diameter, branches per plant, number of node and ears per plant, yield of stem in fresh and dry were the highest at the sowing time from March 30 to April 30. Optimum sowing time of Schizonepeta tenuifolia Briquet were shown to be from March 30 to April 30 in southern areas of Korea.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2000.05a
• /
• pp.34-37
• /
• 2000

To determine the optimum planting density in Alisma plantago in the southern areas of Korea, Alisma plantago local cultivar was grown under different planting density. The plant height, number of stems and diameter of root were 30cm, 12 and 3.4mm respectively on the planting density, row 20cm $\times$ intrarow 35cm. The fresh yield of root and dry yield of root were 261.2Kg110a, 211.5Kg/10a respectively on the planting density, row 20cm x intrarow 35cm. Therefore, the proper planting density for high yield bumper crop of Alisma plantago for exporting to Japan is planting density with row 20cm $\times$ intrarow 35cm.

• Plant Resources
• /
• v.7 no.3
• /
• pp.211-215
• /
• 2004

The effects of topping method on the yield and major agronomic traits of two varieties, Sunwol and Youngjun of Alisma plantago, were investigated in the Southern region. Plant height, yield of fresh root, yield of dry root and weights of total roots were the highest in the variety of Sunwol, and at the plots with topping of four times cutting in flowering in main culm (Treatment No.1). Considering from our results, optimum topping method is most likly be topping of four times cutting in flowering in main culm in the Sunwol variety.

• Korean Journal of Soil Science and Fertilizer
• /
• v.15 no.3
• /
• pp.178-187
• /
• 1982

This pot experiment was undertaken to find out the optimum fertilization ratios of total anions to total cations, ${\Sigma}A/{\Sigma}C$, and the optimum application rates of total macro-nutrients in various soil conditions. Soil samples were collected from uncultivated mountains and hills where grassland development was under consideration. 1. The optimum application ratios of ${\Sigma}A/{\Sigma}C$ and the optimum application rates of total macro-nutrients for the high yields of mixed grass-clover sward in various grassland soils were computed by the Hom$\acute{e}$s systematic variation techniqu.e. 2. With respect to the optimum application ratios of ${\Sigma}A/{\Sigma}C$ in fertilization in a mixed grass-clover sward, the grass yield and botanical composition were distinctly proportional to ${\Sigma}A$ wheras the regume yield and botanical composition were proportional to ${\Sigma}C$. 3. The optimum fertilization rates of total macro-nutrients for the high legume yields were depended upon ${\Sigma}A/{\Sigma}C$ ratios. These optimum rates were in proportional to ${\Sigma}C$ ratios and were inversely proportional to ${\Sigma}A$ ratios. 4. The efficiencies of ${\Sigma}A$ and ${\Sigma}C$ in relation to the grass and grass plus legume yields were highest with the low ratios of each other and the low fertilization rates of total macronutrients. The ${\Sigma}A$ effieiency in the legume yield tended to be similar to that of ${\Sigma}A$ related to the grass yield noted above except Daegu soil. The ${\Sigma}C$ efficiency, however, was proportional to the ${\Sigma}C$ ratio, although that was varied with the fertilization rates of total macro-nutrients and with the kinds of soils. 5. The yield of mixed forages, yield component, and botanical composition in a mixed sward were greatly influenced by the ${\Sigma}A/{\Sigma}C$ ratios, the fertilization rates of total macronutrients, and the interactions of ratio and rate noted above. In addition, these effects were generally different and opposite according to grass and legume.

• 한국생물공학회:학술대회논문집
• /
• 2001.11a
• /
• pp.894-897
• /
• 2001

This experiment was to determine the optimum conditions for D-sorbitol cyclization in the presence of p-toluenesulfonic acid(p-TSA) as acid catalyst before the esterification of sorbitol with fatty acids. The optimum conditions of hydration reaction to obtain maximum yield of 1,4-sorbitan were at $130^{\circ}C$, 200mmHg reduced pressure, after l50min and l%(w/w) p-TSA. In this condition the yield of 1,4-sorbitan was approximately 90%.

• Journal of Microbiology and Biotechnology
• /
• v.6 no.1
• /
• pp.63-67
• /
• 1996

Bacteriocin-producing microorganism was isolated from Kimchi. The microorganism was identified as a Lactobacillus sp. and named Lactobacillus sp. JB-42. The optimum conditions for the bacteriocin production from the isolated microorganism were evaluated. For the maximum yield of bacteriocin from Lactobacillus sp. JB-42, the cell should be harvested at the early stationary phase and the temperature, pH and NaCl concentration should be $30^{\circ}C$, pH 7 and without the addition of NaCl, respectively. Sucrose, glucose or fructose should be used as a carbon source and organic nitrogen such as tryptone should be used as a nitrogen source for the best yield. The production of bacteriocin was related to the cell growth of Lactobacillus sp. JB-42 indicating the role of Lactobacillus in the Kimchi fermentation process.

• Journal of Environmental Science International
• /
• v.4 no.3
• /
• pp.259-267
• /
• 1995

This study was conducted to evaluate the effects of pressure and dissolved oxygen concentration on the activated slut비e and to determine the optimum depth of deep shaft process. Some results from this study were summarized as follows. 1. It is considered that low sludge product in the activated sludge system maintaining high dissolved oxygen concentration is attributed to the increase of endogeneous respiration rate caused by the increase of aerobic zone in the sludge floe. 2. The increase of dissolved oxygen concentration does not affect to the increase of organic removal efficiency greatly and therefore the limiting factor is the substrate transfer into the inner part of floe. 3. The yield coefficient, Y is decreased in proportion to the increase of oxygen concentration. In this study, Y values arre ranged from 0.70 to 0.41 according to the variation of dissolved oxygen concentration from 18.0mg/$\ell$ to 258 mg/$\ell$. 4. The optimum depth of deep shaft process should be determined within the limits of non-toxicity to the microorganism and it is about loom in this study.

• Microbiology and Biotechnology Letters
• /
• v.27 no.5
• /
• pp.399-403
• /
• 1999

For the production of trehalose, microorganisms capable of producing trehalose extracellularly were screened from the stock cultures in our laboratory. among them, Micrococcus luteus IFO 12708 showed the highest productivity of trehalose. For the increase of productivity, the mutant strai Hs-208 having higher trehalose production was selected with NTG(N-methyl-N'-nitrosoguanidine) mutagenesis, which led to the decrease of the specific activity of trehalose phosphorylase(3.2-fold) as compared to the wild strain. The optimum condition for the trehalose production was established as follows: 20g/l of glucose and 6g/l of tryptone were used as a sole carbon source and nitrogen source, respectively, and cultivations were carried out at 3$0^{\circ}C$ and pH 6.0. After 20hrs cultivation, addition of 20unit/ml penicillin G led to the higher conversion yield of trehalose. Under the optimum condition, 6.547g/l trehalose was produced with conversion yield of 32.7%.

• Fibers and Polymers
• /
• v.5 no.2
• /
• pp.117-121
• /
• 2004

Optimum condition concerning the content of pretreatment print paste and steaming time for ink-jet printing was newly developed through the orthogonal analysis. The cotton fabric treated under the newly developed optimum condition could achieve a high level of colour yield similar to that of the commercially pretreated cotton fabric available in the market for ink-jet printing. The results were discussed thoroughly in this paper.