• Korean Journal of Soil Science and Fertilizer
• /
• v.30 no.3
• /
• pp.265-271
• /
• 1997

The salt accumulation, and chemical properties of 90 samples of the plastic film house soil in the area of Cheongju and Chungju were surveyed. Soil textural distribution of soil samples was 30% for sandy loam, 27% for loam and 43% for silty loam. Percentage distribution of electrical conductivity(EC) of surface soil was 23% below $2dS\;m^{-1}$, 30% for $2{\sim}4dS\;m^{-1}$, 25% for $4{\sim}6dS\;m^{-1}$ and 22% over $6dS\;m^{-1}$. Salt affected soil, which EC was higher than $4dS\;m^{-1}$, covered nearly 50% of all field surveyed. However subsoils(20~30cm) below $2dS\;m^{-1}$ was 68%. Salts in plastic film house soil was accumulated by increasing the cultivation period. After 5 years of cultivation electrical conductivity in plastic house soil was generally higher than $4.47dS\;m^{-1}$ in EC that was 2.8~5.6 times higher than that in the field soil in the outside of plastic film house. As the result of temporary removal of plastic film cover from the house during the rainy summer season, salt content in soil was decreased from $3.54{\sim}7.36dS\;m^{-1}$ to $0.71{\sim}2.92dS\;m^{-1}$ in EC due to the desalinization by runoff and percolating water. Contents of $NO_3-N$, $SO_4-S$ and Cl in plastic film house soil were 2.5. 7.0 and 3.4 times higher than those of open field respectively.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2003.05a
• /
• pp.247-251
• /
• 2003

In this paper, we propose an approximation of the M/G/1 system with finite workload capacity, where customers whose admission to the system would increase the workload beyond a prespecified finite capacity limit are not accepted. Our approximation method is based on the idea that the service time of a customer in the M/G/1 system can be approximated as the sum of service times of a batch of customers in the $M^{X}/d/1$ system where the service time is deterministic and very small. That is, the original service time is discretized and approximated by the batch size. We exemplified our method by obtaining the average workload of the M/M/1 system by means of the $M^{X}/d/1$ system, where the batch size is geometric. In addition, the approximate blocking probabilities of the M/M/1 and $M/E_{k}/1$ system with finite workload capacities are sought. The proposed method turns out to give a good approximation, which is compared with a simulation.

• Korean Journal of Animal Reproduction
• /
• v.25 no.1
• /
• pp.63-69
• /
• 2001

This study was carried out to examine the effects of nitric oxide compounds (hemoglobin and L-NAME) on the development of porcine in vitro maturation (IVM) and in vitro fertilization (IVF) oocytes. Cumulus cell free embryos derived from porcine IVM/IVF oocytes were cultured in NCSU23 medium containing 1~5 $\mu\textrm{g}$/$m\ell$ hemoglobin added to 44 and 96hrs in culture times, and in NCSU23 medium containing 0, 10, 50 or 100mM L-NAME. The developmental rates beyond morulae stage in 0, 1 and 5 $\mu\textrm{g}$/$m\ell$ hemoglobin groups add to 44hrs in vitro culture times were 52.4%, 57.6% and 57.4%, respectively. The addition of hemoglobin groups made it slightly higher than the control group. The proportion of embryos developed to morulae and blastocysts in 1 $\mu\textrm{g}$/$m\ell$ hemoglobin add to 96hrs after in vitro culture (70.8%) was a little higher than those of 0 and 5 $\mu\textrm{g}$/$m\ell$ hemoglobin (66.2% and 62.8%). There was no significant difference in all groups (P〉0.05). The developmental rates beyond morulae stage in 0, 10, 50 and 100mM of L-NAME groups add to 96hrs after in vitro culture were 65.2%, 73.5%, 70.1% and 53.3%, respectively 10mM and 50mM L-NAME groups were significantly higher than in 0 and 100mM of L-NAME groups (P＜0.05). In conclusions, these results indicate that L-NAME (10mM, 50mM) can increase the proportion of embryos that develop into morulae and blastocysts but hemoglobin did not affect.

• Clinical and Experimental Reproductive Medicine
• /
• v.23 no.3
• /
• pp.351-355
• /
• 1996

Objective: To analyze the direct effect of nitre oxide, generated from sodium nitroprusside, on sperm motility and reactive oxygen species. Design: Human sperm samples were treated to allow swim-up and washing. And the samples were devided into four aliquots. Each aliquot was incubated with either concentration at 0, 100nM, $10{\mu}M$, 1mM of nitroprusside. Intervention: Samples were measured chemiluminosence for reactive oxygen species of each aliquot with concentrations at 0, 100nM, $10{\mu}M$, 1mM of nitroprusside at allowing swim-up and washing of sperm. Main Outcome Measures: Percent motion parameters and viability were asse-ssed at 0, 3, 6, 12, 24 hours incubation. Results: The percent viablity was lower slightly in control group (50.2%) than that in sperm treated with 100nM of nitroprusside(57.5%) at 24 hours after incubation, while was reduced significantly in sperm with concentra-tion of $10{\mu}M(42.1%)$ and 1mM(21.3%)of nitroprusside at 6 hours after incubation. And the sperm treated with 1mM of nitroprusside was immotile totally at 6 hours after incubation. The straight line$(35.3{\pm}5.6%)$, the rapid forward$(37.2{\pm}6.4%)$ and the weak curvilinear velocity$(9.6{\pm}2.4%)$were more favorable comparing with those ($32.4{\pm}4.2%$, $30.0{\pm}7.8%$ and $18.0{\pm}4.6%$ respectively) in control group at 3 hours after incubation, but reduced significantly in sperm treated with $10{\mu}M$ and 1mM of nitroprusside. The levels of reactive oxygen species in control(700 c.p.m.) is lower significantly than that in each experimental groups of sperm treated with nitroprusside. And the levels of reactive oxygen species were 2200 c.p.m. in 100nM, 6200c.p.m. in $1{\mu}M$ and 12800c.p.m. in 1mM respectively. Conclusion: These results suggested that the concentration of 100nM of nitroprusside on sperm is beneficial to the maintanance of viablity and motile velocity, but detriment in high concentration of $10{\mu}M$ or 1mM of nitroprusside.

• Journal of the Korean Statistical Society
• /
• v.36 no.2
• /
• pp.285-297
• /
• 2007

We consider the $P_{\lambda}^M-service$ policy for an M/G/1 queueing system in which the workload is monitored randomly at discrete points in time. If the level of the workload exceeds a threshold ${\lambda}$ when it is monitored, then the service rate is increased from 1 to M instantaneously and is kept as M until the workload reaches zero. By using level-crossing arguments, we obtain explicit expressions for the stationary distribution of the workload in the system.

• Journal of Korean Institute of Industrial Engineers
• /
• v.35 no.2
• /
• pp.171-177
• /
• 2009

This study presents the switching strategy between admission control and pricing control policies and clarifies the properties of the switching strategy in an M/M/1/K queueing system. In addition, this study demonstrates that employing the switching strategy can significantly improve the maximum total expected profit.

• Proceedings of the Korean Information Science Society Conference
• /
• 2000.04a
• /
• pp.680-682
• /
• 2000

이 논문은 에지와 정점에 고장이 있는 이중 루프 네트워크의 해밀톤 성질을 고려한다. 이중 루프 네트워크 G(mn;1,m)은 m$\times$n 그리드 그래프에 에지를 추가한 4-정규 그래프이다 m과 n이 모두 짝수인 이중 루프 네트워크G(mn;1,m)은 고장난 요소(에지와 정점)의 수가 1이하인 경우에 해밀톤 연결되어 있고, 고장난 요소의 수가 2이하인 경우에 항상 해밀톤 사이클을 가짐을 보인다.

• Food Science of Animal Resources
• /
• v.35 no.5
• /
• pp.646-652
• /
• 2015

The beef forequarter muscle comprises approximately 52% of carcass weight. The objective of this study was to evaluate the physiochemical characteristics and meat color from forequarter muscle of Holstein steers. Fifteen forequarter muscles were trimmed of external connective tissue and fat. An experimental group of eight Holstein steers was assessed using meat color, water-holding capacity, drip loss, and Warner-Bratzler shear force value at the same quality grade. The M. omotransversarius (0.45 kg) had the highest (p<0.05) lightness (L*) value, whereas the M. teres major (0.4 kg) and M. triceps brachii (caput laterale) (0.52 kg) had the lowest (p<0.05) values. The M. semispanitus capitus (1.48 kg), which is a neck muscle, had the highest values for both redness (a*) and yellowness (b*), whereas the lowest (p<0.05) values were for the M. teres major. The M. omotransversarius, M. latissimus dorsi (1.68 kg), and M. rhomboideus (1.2 kg) were ranked high (p<0.05) in water-holding capacity. The drip loss value was the highest for the M. longissimus dorsi thoracis (p<0.05; 1.86 kg), while the M. infraspinatus (2.28 kg), M. supraspinatus (1.38 kg), M. brachiocephalicus (1.01 kg), and M. pectoralis superficialis (1.18 kg) had the lowest (p<0.05). The Warner-Bratzler shear force value indicated that the M. pectoralis profundus (3.39 kg), M. omotransversarius, and M. brachiocephalicus were the toughest (p<0.05), whereas the M. subscapularis (0.86 kg), M. longissimus dorsi thoracis, M. teres major, and M. infraspinatus were the most tender cuts (p<0.05). Here, muscle type explained most of the variability in the forequarter physiochemical characteristics. Thus, our findings suggest that these muscle profile data will allow for more informed decisions when selecting individual muscles to produce value-added products from Holstein steers.

• The Korean Journal of Pesticide Science
• /
• v.7 no.1
• /
• pp.12-17
• /
• 2003

Potato blackleg disease caused by Erwinia carotovora subsp. atroseptica (Eca) has been a serious problem in Korea. Bactericidal activities of twelve bactericides including antibiotics, copper compounds and oxolinic acid were examined in vitro. Streptomycin, streptomycin sulfate, and oxolinic acid effectively controlled the pathogen at 0.02 mM. However, the pathogen developed resistance to the applied bactericides after 72 hours of incubation. Activity of copper compounds such as copper hydroxide, copper oxide and copper sulfate was lower than that of antibiotics. However, the pathogen did not develop resistant to them. Combinations of streptomycin (0.016 mM, 9.3 ppm) + copper oxide (1.2 mM, 171.6 ppm)/copper hydroxide (1.5 mM, 146.3 ppm); streptomycin sulfate (0.005 mM, 7.0 ppm) + copper oxide (1.2 mM, 171.6ppm)/copper hydroxide (1.5 mM, 146.3 ppm) were found to be effective for the control of E. carotovora subsp. atroseptica.

• Biomedical Science Letters
• /
• v.30 no.2
• /
• pp.96-99
• /
• 2024

In vitro antimicrobial activities of hot water extracts of Chamaecyparis obtuse, for clinical metallo-β-lactamase-Producing Pseudomonas aeruginosa (MBLPA.) was compared to commonly used conventional antimicrobial agents. All MBLPA was susceptible to colistin or amikacin, but also to imipenem 88.6%, meropenem 100%, piperacillin 85.7%, ceftazidime 97.1%, gentamicin 97.1%, and ciprofloxacin 100% were non-susceptible. MIC range to imipenem, meropenem, cefotaxime, ceftazidime, gentamicin, and ciprofloxacin for MBLPA were each 1 - >128 ㎍/mL, 4 - >128 ㎍/mL, 4 - >128 ㎍/mL, 8 - >128 ㎍/mL, 4 - >128, and 2- >128 ㎍/mL. MIC range to aztreonam for MBLPA were 1 - 128 ㎍/mL. MIC₉₀ to imipenem, meropenem, cefotaxime, ceftazidime, gentamicin, and ciprofloxacin for MBLPA were each 32 ㎍/mL, >128 ㎍/mL, >128 ㎍/mL, >128 ㎍/mL, >128 ㎍/mL, and 128 ㎍/mL. MIC₉₀ to colistin and amikacin were each 1 ㎍/mL and 64 ㎍/mL. The hot water extracts of C. obtuse leaf had the lowest MIC range (0.25 - >0.5 μL/mL), MIC₅₀ (>0.5 μL/mL), and MIC₉₀ (>0.5 μL/mL) of the clinical MBLPA tested, and it was possible more potent than various conventional antimicrobial agents for MBLPA infection patients. Therefore, it suggested the possibility of using extract components of C. obtuse or their derivatives to treat MBLPA infection patients.