• Journal of Bio-Environment Control
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• v.5 no.2
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• pp.120-130
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• 1996

Crisphead lettuce(Lactuca sativa L.) was grown in NFT to investigate the effects of NO$_3$-N and NH$_4$-N ratio in nutrient solution and elevated $CO_2$ treatment in the crisphead lettuce growth. This experiment has been conducted under three different ratios of NO$_3$-N:NH$_4$-N(100:0, 75:25, 50:50) with two $CO_2$ concentration (control, 1500ppm ). The results are as follows; 1. In the case of not controlling pH and EC in nutrient solution, pH was gradually increased in NO$_3$-N:NH$_4$-N=100:0 treatment but rapidly decreased in the nutrient solution 2. Daily changes of NO$_3$-N and NH$_4$-N were observed without controlling the nutrient solution. In the treatments of NO$_3$-N:NH$_4$-N ratios were 75:25 and 50:50, NO$_3$-N absorption rates were 27.7% and 26.1%, while NH$_4$-N absorption rates were 87.9% and 71.2%, respectively. 3. There was little differences in total nitrogen of leaves. However phosphorus, potassium, calcium and magnesium contents were highly shown in the treatment of $CO_2$ 1500ppm and 100:0 ratio of NO$_3$-N:NH$_4$-N. 4. Higher $CO_2$ assimilation rate was shown in plants grown under $CO_2$ 1500ppm and 100:0 ratio of NO$_3$-N:NH$_4$-N. It dropped significantly with the increase of NH$_4$- N rates in nutrient solution. 5. Fresh weight, leaf number, root length and root weight of crisphead lettuce were far better in the treatment of $CO_2$ 1500ppm and 100:0 ratio of NO$_3$-N:NH$_4$-N. Growth differences by $CO_2$ elevation were not shown in other NO$_3$-N:NH$_4$-N treatments. 6. The highest nitrate contents of leaves were shown in NO$_3$-N single treatment but shown the lowest vitamin C contents. Nitrate contents of leaves were decreased by $CO_2$ but the effect was slight treatment.

• Journal of Bio-Environment Control
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• v.1 no.1
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• pp.21-27
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• 1992

The effects of different night temperatures and NO$_3$$^{[-10]}$ : NH$_4$$^{+}$ ratios in nutrient solution on the growth and quality of Chinese white cabbage(B. chinensis L. var. chinensis) and Chinese flat cabbage(B. chinensis L. var. rosularis) were studied. The results were summarized as follows. 1. Fresh weight was increased higher in night temperature 15$^{\circ}C$ than 5, 1$0^{\circ}C$, but content of vitamin C and dry weight ratio were increased as night temperature was lower. 2, The growth of Chinese white cabbage and Chinese flat cabbage was bad extremely in NO$_3$$^{[-10]}$ : NH$_4$$^{+}$(0 : 8), and the others were little different 3. In nutrient solution, the higher NO$_3$$^{[-10]}$ -N concentration was, the more content of vitamin C, and the higher NH$_4$$^{+}$-N concentration was, the more dry weight ratio.ratio.

• Journal of Bio-Environment Control
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• v.3 no.2
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• pp.99-105
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• 1994

The objective of this study was conducted for elucidation of effects of the NO$_3$$^{[-10]}$ -N. NH$_4$$^{+}$-N ratio in the nutrient solution on the growth and quality of welsh onion(Allium fistulosum L.). The pH of nutrient solution increased in NO$_3$$^{[-10]}$ -N : NH$_4$$^{+}$-N ratio of 9 : 1 treatment, decreased in 1 : 1, 1 : 3 treatment, but was stable in 3 : 1 treatment during cultivation. The apparent growth of welsh onion was best in the treatment of 9 : 1(NO$_3$$^{[-10]}$ -N : NH$_4$$^{+}$-N ratio), however the treatment of 1 : 3 resulted in poor growth. The NO$_3$$^{[-10]}$ -N content of the plants increased in proportion to that content of nutrient solution. Pyruvic acid content of welsh onion was highest at 9 : 1, 3 : 1 treatment, and lowest at 1 : 3 treatment.tment.

• Journal of Bio-Environment Control
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• v.2 no.2
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• pp.119-125
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• 1993

The effect of NO$_3$-N and NH$_4$-N ratio on the growth of Perilla frutescens in deep flow culture was studied in winter season. NO$_3$-N and NH$_4$-N were treated in the ratios of 12 : 0, 9 : 3, 6 : 6(me/ $\ell$ ). The pH of the nutrient solution was increased an NO$_3$-N:NH$_4$-N=12 : 0 treatment, and decreased in the treatments containing NH$_4$-N, greatly in NO$_3$-N : NH$_4$-N = 6 : 6 treatment. The EC was increased regardless of treatments, but more increased in the treatments containing NH$_4$-N. The stem-base circumference, plant height, root weight, shoot weight, and yields of leaves were by far the highest in NO$_3$-N:NH$_4$-N=6 : 6 treatment and the lowest in NO$_3$-N:NH$_4$-N= 12 : 0 treatment. Among the mineral contents of leaves, N, K, Fe and P were higher in the treatments containing NH$_4$-N. Ca, Mg and Mn were higher in NO$_3$-N :NH$_4$-N= 12 : 0 treatment.

• 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.10 no.1
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• pp.50-54
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• 2001

Effect of NO$_3$:NH$_4$ratio and pH of nutrient solution on nitrate content of leaves was investigated for leaf lettuce(Lactuca sativa L.) grown by a deep flow technique. Ratios(in me.L$^{-1}$ ) of NO$_3$:NH$_4$tested were 12:1, 10:3 and 8:5. The treatment of 8:5 NO$_3$:NH$_4$ratio had two solutions, one with uncontrolled pH and the other with automatically controlled pH. Solution pH continuously increased in 12:1 NO$_3$:NH$_4$treatment. Solution pH decreased gradually more as NH$_4$ratio increased. Treatment of 8:5 NO$_3$:NH$_4$with automatic pH control satisfactorily maintained the solution pH in the range of pH 5.5-6.0. Nitrate content in leaves was the greatest in treatment of 12:1 NO$_3$:NH$_4$ and the least in treatment of 8:5 NO$_3$:NH$_4$with automatic pH control. Fresh weight decreased in treatments of 10:3 and 8:5 NO$_3$:NH$_4$, whereas it increased in treatments of 12:1 and 8:5 NO$_3$:NH$_4$with pH control. It was concluded that the growth and leaf nitrate content were the greatest in high NH$_4$treatment with automatic pH control.

• Korean Journal of Materials Research
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• v.9 no.11
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• pp.1129-1136
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• 1999

TIN films were prepared on Si(100) substrate by ICP-CVD(inductive1y coupled plasma enhanced chemical vapor deposition) using TEMAT(tetrakis ethylmethamido titanium : Ti$[\textrm{N}\textrm{(CH)}_{3}\textrm{C}_{2}\textrm{H}_{5}]_{4}$) precursor at various deposition conditions. Phase, microstructure, and the electrical properties of TIN films were characterized by x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), high resolution transmission electron microscopy (HRTEM) and electrical measurements. Polycrystalline TiN films with B1 structure were grown at temperatures over $200^{\circ}C$. Preferentially oriented along TiN(111) films were obtained at temperatures over $300^{\circ}C$ with the flow rates of 10, 5, and 5 sccm for TEMAT, $\textrm{N}_{2}$ and Ar gas. The TiN/Si(100) interface was flat and no chemical reaction between TIN and $\textrm{SiO}_2$ was found. The resistivity, carrier concentration and the carrier mobility for the TiN sample prepared at $500^{\circ}C$ are 21 $\mu\Omega$cm, 9.5$\times\textrm{10}^{18}\textrm{cm}^{-3}$ and $462.6\textrm{cm}^{2}$/Vs, respectively.

• Proceedings of the Korea Crystallographic Association Conference
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• 2001.05a
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• pp.16-16
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• 2001

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.2
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• pp.323-329
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• 2002

This paper describes an efficient error-compensation technique for designing a low-error truncated Booth multiplier which produces an N-bit output from a two's complement multiplication of two N bit inputs by eliminating the N least-significant bits. Applying the proposed method, a truncated Booth multiplier for area-efficient and low-power applications has been designed, and its performance(truncation error, area) was analyzed. Since the truncated Booth multiplier does not have about half the partial product generators and adders, it results an area reduction of about 35％, compared with no-truncated parallel multipliers. Error analysis shows that the proposed approach reduces the average truncation error by approximately 60％, compared with conventional methods. A 16-b$\times$16-b truncated Booth multiplier core is designed on full-custom style using 0.35-${\mu}{\textrm}{m}$ CMOS technology. It has 3,000 transistors on an area of 330-${\mu}{\textrm}{m}$$\times$262-${\mu}{\textrm}{m}$ and 20-㎽ power dissipation at 3.3-V supply with 200-MHz operating frequency.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.4
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• pp.308-315
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• 2003

A field experiment was conducted to investigate the performance of three legume species in a zero-tillage, non-fertilized rice field in a temperate zone. Before the experiment for 5 years, from 1995 to 1999, plant growth patterns of three legume species grown as over-wintering (October-May) cover crops on a paddy field were maintained to study N balance and $\textrm{N}_2$ fixation. Decrease in plant density accelerated from after winter to flowering from 1,090, 320, and 5 to 732, 232, and 6 plants $\textrm{m}^{-2}$ in Chinese milk vetch (CMV), white clover (WC), and hairy vetch (HV), respectively. Total dry weights of plants above-ground level were 0.05, 0.11, and 2.43 g $\textrm{plant}^{-1}$. in WC, CMV and HV respectively but steeply increased at ripening up to 0.77, 2.33, and 26 g $\textrm{plant}^{-1}$. The root dry weight of HV and CMV rapidly increased while in WC, root dry weight increased slightly towards flowering. The highest nodule numbers were recorded in CMV to April thereafter WC produced the highest. Nodule size was distributed within 7mm in CMV but it was larger in HV varying from 1 to 10mm. Shoot N (g $\textrm{m}^{-2}$) greatly increased from over-wintering to flowering in CMV, HV and WC and it ranged from 1.66, 0.5 and 1.92 to 12.6, 3.1 and 13.02 g $\textrm{m}^{-2}$, respectively. After wintering, the initial shoot N content (%) was more in CMV. Root N content (%) was constant or slightly decreased in HV and WC. Soil total N in the control plot (clean fallow) was the highest on Mar. 2 then decreased rapidly to flowering. Soil N content was constant in HV plots whereas it was low in WC plots for the entire growth period except just after winter. Maximum nitrogenase activities were 9, 37.8, and 131 mol $\textrm{C}_2\textrm{H}_4$ $\textrm{plant}^{-1}$ $\textrm{hour}^{-1}$. in CMV, HV, and WC, respectively. Nitrogenase activity showed a direct correlation with nodule number, size and fresh weight. As a cover crop preceding a rice crop, CMV is more suited to colder regions due to its earlier ripening characteristics. Hairy vetch and WC are recommended for regions with a mild winter and a long summer owing to their late ripening and great N fixation activity.