• Bulletin of the Korean Mathematical Society
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• v.58 no.4
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• pp.915-937
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• 2021

In this paper we deal with the open problem posed by Lü, Li and Yang [10]. In fact, we prove the following result: Let f(z) be a transcendental meromorphic function of finite order having finitely many poles, c₁, c₂, …, c_n ∈ ℂ\{0} and k, n ∈ ℕ. Suppose fⁿ(z), f(z+c₁)f(z+c₂) ⋯ f(z+c_n) share 0 CM and fⁿ(z)-Q₁(z), (f(z+c₁)f(z+c₂) ⋯ f(z+c_n))^(k) - Q₂(z) share (0, 1), where Q₁(z) and Q₂(z) are non-zero polynomials. If n ≥ k+1, then $(f(z+c_1)f(z+c_2)\;{\cdots}\;f(z+c_n))^{(k)}\;{\equiv}\;{\frac{Q_2(z)}{Q_1(z)}}f^n(z)$. Furthermore, if Q₁(z) ≡ Q₂(z), then $f(z)=c\;e^{\frac{\lambda}{n}z}$, where c, λ ∈ ℂ \ {0} such that e^{λ(c₁+c₂+⋯+c_n)} = 1 and λ^k = 1. Also we exhibit some examples to show that the conditions of our result are the best possible.

• The Korean Journal of Pesticide Science
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• v.4 no.2
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• pp.63-68
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• 2000

This study was conducted to investigate insecticidal mechanisms of the new insecticides DBI-1015 and DBI-3204 with label compounds of chitin precursors, [$^{14}C$] N-acetylglucosamine and [$^{14}C$] UDP-N-acetylglucosamine in Spodoptera litura. The concentrations of the insecticides for incorporation of chitin precursors into chitin were founded to be functional relationship. The result of in vivo test, $I_{50}$ (ppm) of the DBI-1015, DBI-3024 and diflubenzuron to [$^{14}C$] N-acetylglucosamine were 0.57, 0.89 and 0.26 ppm respectively, and to [$^{14}C$] UDP-N-acetylglucosaminen were 0.99, 0.53 and 0.45 ppm respectively. in vitro test of DBI-1015, DBI-3024 and diflubenzuron by integument fragments, the incorporation rate in the cuticle were low, however, $40{\sim}60%$ inhibitions were observed at $2{\mu}M$ when compared to the untreated control.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.10
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• pp.1441-1448
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• 2008

This experiment was carried out to study the carcass characteristics, chemical composition and fatty acid profile of the Longissimus muscle (LM) of bulls (10) and steers (17) finished in a pasture system. Animals (1/2 Zebu vs. 1/2 Aberdeen Angus) were fed in a pasture system (Hermatria altissima) and with a supplement of soybean meal, cracked corn, urea, limestone and mineral salts, twice a day. Both animal groups were slaughtered at 27 months of age, with an average 508.88 kg of live weight. Final weight, hot carcass weight and texture were similar (p>0.05) between bulls and steers. Carcass dressing, fat thickness, color and marbling were higher (p<0.02) in steers. Conversely, the Longissimus area was greater (p<0.05) in bulls. Moisture levels were higher (p<0.01) in bulls. Ash, crude protein, total lipids and total cholesterol levels were higher (p<0.10) in steers. C14:0, C16:0, C16:1 n-7 and C18:1 n-9 fatty acids percentages were higher (p<0.06) in steers. C16-1 n-10, i 17:0, C19:0, C18:2 n-6, C18:3 n-3, C20:2 n-3 C20:4 n-6, C20:5 n-3, C22:1 n-7, C22:4 n-6 and C22:5 n-3 fatty acids percentages were higher (p<0.05) in bulls. The percentage of the other fatty acids was similar (p>0.05) in bulls and steers. The levels of monounsaturated fatty acids were higher (p<0.02) in steers while polyunsaturated fatty acids, n-3, n-6, PUFA/SFA and n6:n3 ratios, were higher (p<0.05) in bulls. The CLA contents (mg/g lipids) were similar (p>0.10) in bulls and steers.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.11
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• pp.1174-1179
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• 2005

Up-flow sludge blanket(USB) reactors were used to investigate the effects of N/C(${NO_3}^--N/COD$) ratio on simultaneous denitrification and methanogenesis processes. Without nitrate feeding, 84% of the influent COD was converted into methane. With the increase of N/C ratio, nitrogen gas increased while methane production decreased and stopped finally at the N/C ratio over 0.20. Influent nitrate was completely denitrified into nitrogen gas while nitrate removal efficiency dropped below 40% at N/C ratio of 0.40 because of deficiency in organic carbon. Fraction of COD utilized by denitrification increased at higher N/C ratios. Methanogenesis started to be effected at N/C ratio of 0.05, which could explain the competition for organic carbon between these microorganisms such as denitrifiers and methanogens, rather than inhibitory effect of nitrate and its intermediates. Critical N/C ratio for simultaneous denitrification and methanogenesis was found to be 0.20. Influent COD was removed over 92% by denitrification, methanogenesis and other biochemical reactions including cell growth at these N/C ratios.

• Journal of the Korean Ceramic Society
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• v.35 no.12
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• pp.1316-1322
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• 1998

The amount of VC and C/N ratio in Ti(CN) was varied to investigate the effect of VC addition on the mi-crostructural change in Ti(CN)-Ni system. As the amount of VC addition increases in Ti(C0.7N0.3)-20Ni sys-tem a complete solid solution was observed in Ti(C0.7N0.3)-20Ni-25VC system. It implies that the ratio of the dissolution rates of Ti(C0.7N0.3)to that of VC is nearly 2:1 at the sintering conditions used in this study. It was found from the experiments that the system composed of the Ti(C0.7N0.3) phase exhibits a rimless structure and relatively small amount of solid solution. That is among Ti(C0.7N0.3) phase exhibits a rimless structure and relatively small amount of solid solution. This is among Ti(C1-xNx) phases the dissolution rate of Ti(C0.3N0.7) is the lowest. Also fracture toughness(KIC) of the cermet was measured by indentation method. Attentions were paid to crack propagation path to look for a dominant fracture mode and to cor-relate it with fracture toughness values. The fracture toughness was relatively high with the addition of VC content. But the addition of a large VC content reduced the overall toughness of the cermet. This result is explained with the difference in fracture mode.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.6
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• pp.712-719
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• 2016

Understanding N mineralization dynamics in soil is essential for efficient nutrient management. An anaerobic incubation experiment was conducted to examine N mineralization potential and N mineralization rate of the organic amendments with different C:N ratio in paddy soil. Inorganic N in the soil sample was measured periodically under three temperature conditions ($20^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$) for 90 days. N mineralization was accelerated as the temperature rises by approximately $10%^{\circ}C^{-1}$ in average. Negative correlation ($R^2=0.707$) was observed between soil inorganic N and C:N ratio, while total organic carbon extract ($R^2=0.947$) and microbial biomass C ($R^2=0.824$) in the soil were positively related to C:N ratio. Single exponential model was applied for quantitative evaluation of N mineralization process. Model parameter for N mineralization rate, k, increased in proportion to temperature. N mineralization potential, $N_p$, was very different depending on C:N ratio of organic input. $N_p$ value decreased as C:N ratio increased, ranged from $74.3mg\;kg^{-1}$ in a low C:N ratio (12.0 in hairy vetch) to $15.1mg\;kg^{-1}$ in a high C:N ratio (78.2 in rice straw). This result indicated that the amount of inorganic N available for crop uptake can be predicted by temperature and C:N ratio of organic amendment. Consequently, it is suggested that the amount of organic fertilizer application in paddy soil would be determined based on temperature observations and C:N ratio, which represent the decomposition characteristics of organic amendments.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1786-1793
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• 2005

The study compared the fatty acid profiles of 3 muscles (Longissimus dorsi, LD, Triceps brachii, TB and Semimembranosus, SM) obtained from Korean Hanwoo (18 steers, 24 months old) and Australian Angus beef (18 steers, 24 months old) and assessed their role in sensory perception. The samples of each carcass were prepared in the same manner, and cooked both as traditional grilled steaks and Korean BBQ style. A total of 720 Korean sensory panelists evaluated the beef samples for tenderness, juiciness, flavor, and overall liking. Oleic acid (18:1) was significantly (p<0.05) higher in TB than that in LD and SM. The essential linoleic acid (C18:2) was significantly (p<0.05) higher in TB and SM than that in LD. For LD muscle, the proportion of saturated fatty acids was significantly (p<0.05) highest, while that of polyunsaturated fatty acids was lowest among the three muscles. Australian Angus beef had significantly (p<0.05) higher n-3 PUFA than that of the Korean Hanwoo for the three muscles, while the latter contained significantly (p<0.05) higher n-6 PUFA than that of the former. The clustering analysis showed that there a was significant difference in fatty acids such as C16:0, C16:1n7, C18:0, C18:2n6, C18:3n3, C20:3n6, C20:4n6, C22:4n6, and C22:5n3 for sensory perception (tenderness, juiciness, flavor and overall likeness) of the beef from two origins (p<0.05) among three clusters. Especially, C14:0 had a significant effect on sensory perception only for Korean Hanwoo beef; while C20:5n3 had a significant (p<0.05) effect only for Australian Angus beef based on clustering with the sensory variables.

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.388-396
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• 2003

The freeze dried young antler residue was extracted by proteases and hydrochloric acid(HCl). The young antler was extracted by water at 50$^{\circ}C$ and the residue was reacted by proteases for 5 hours at 50$^{\circ}C$. The extraction rate of its residue was 32.8%(absorbance 3.61 at 280nm) of bacteria protease, 23.8%(absorbance 0.69) of papain, and 31.2% (absorbance 2.96) of pepsin. The young antler was extracted by boiling water and the residue was reacted by proteases for 5 hours at 50$^{\circ}C$. The extraction rate of its residue was 45.0%(absorbance 3.61) of bacteria protease, 30.4%(absorbance 0.33) of papain, and 51.2% (absorbance 2.77) of pepsin. The result of HPLC analysis reveals that in 50$^{\circ}C$ water extract and boiling water extract, all high molecular peak was reduced under MW 1,000 by proteases. The result from the extract of young antler residue reacted by HCl for 5 hours at 50$^{\circ}C$ shows that its extraction rate was 45% (absorbance 0.78) in concentration of 0.1N HCl, 61% (absorbance 1.82) in 0.2N, 81% (absorbance 2.29) in 0.4N, and 82.0% (absorbance 3.28) in 2.0N. The result of HPLC analysis also reveals that in the extract by 0.8N HCl, the peak of about MW 70,000 accounted for 78% in total. Protein content of the extract by 0.8N HCl was 8.2%, and content of amino acid was 81.6%, ash was 1.3%, and mineral contents were 0.1 % of Ca, 2.3% of P, 0.8 % of Mg, 3.4% of Na, 0.002% of F by dry base.

• Journal of Microbiology and Biotechnology
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• v.26 no.7
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• pp.1290-1302
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• 2016

Microalgae are being researched for their potential as attractive biofuel feedstock, particularly for their lipid production. For maximizing biofuel production, it is necessary to explore the effects of environmental factors on algal lipid-producing potential. In this study, the effects of nitrogen (N) sources (NO₂-N, NO₃-N, urea-N, NH₄-N, and N-deficiency) and carbon-to-nitrogen ratios (C/N= 0, 1.0, 3.0, and 5.0) on algal lipid-producing potential of Chlorella sp. HQ were investigated. The results showed that for Chlorella growth and lipid accumulation potential, NO₂-N was the best amongst the nitrogen sources, and NO₃-N and urea-N also contributed to algal growth and lipid accumulation potential, but NH₄-N and N-deficiency instead caused inhibitory effects. Moreover, the results indicated that algal lipid-producing potential was related to C/N ratios. With NO₂-N treatment and carbon addition (C/N = 1.0, 3.0, and 5.0), total lipid yield was enhanced by 12.96-20.37%, but triacylglycerol (TAG) yields decreased by 25.52-94.31%. As for NO₃-N treatment, carbon addition led to a 17.82-57.43%/25.86-82.67% reduction of total lipid/TAG yields. When NH₄-N was used as the nitrogen source, total lipid/TAG yields were increased by 46.67-113.33%/28.99-74.76% with carbon addition. The total lipid/TAG yields of urea-N treatment varied with C/N ratios. Overall, the highest TAG yield (TAG yield: 38.75 ± 5.21 mg/l; TAG content: 44.16 ± 4.35%) was achieved under NO₂-N treatment without carbon addition (C/N = 0), the condition that had merit for biofuel production.

• Korean Journal of Optics and Photonics
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• v.7 no.4
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• pp.363-369
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• 1996

We have performed Brillouin scattering experiments to investigate the elastic properties of tetragonal symmetry single crystal $PbMoO_4$ and could determine the value of birefringence as well as the whole elastic constants. As a result, $c_11=111.4{\pm}4.4,$$, $c_12=64.7{\pm}3.4$, $c_44=27.0{\pm}0.8$, $c_13=51.9{\pm}2.5$, $c_33=95.5{\pm}1.9$, $c_66=34.5{\pm}4.6$ and $c_16=15.8{\pm}1.2({\times}10^9N/m^2)$ and $n_o-n_e=0.151{\pm}0.018$.