• Journal of the Korea Society for Simulation
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• v.24 no.3
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• pp.27-35
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• 2015

We analyze an M/G/1/K queueing system with queue-length dependent service and arrival rates. There are a single server and a buffer with finite capacity K including a customer in service. The customers are served by a first-come-first-service basis. We put two thresholds $L_1$ and $L_2$($${\geq_-}L_1$$ ) on the buffer. If the queue length at the service initiation epoch is less than the threshold $L_1$, the service time of customers follows $S_1$ with a mean of ${\mu}_1$ and the arrival of customers follows a Poisson process with a rate of ${\lambda}_1$. When the queue length at the service initiation epoch is equal to or greater than $L_1$ and less than $L_2$, the service time is changed to $S_2$ with a mean of $${\mu}_2{\geq_-}{\mu}_1$$. The arrival rate is still ${\lambda}_1$. Finally, if the queue length at the service initiation epoch is greater than $L_2$, the arrival rate of customers are also changed to a value of $${\lambda}_2({\leq_-}{\lambda}_1)$$ and the mean of the service times is ${\mu}_2$. By using the embedded Markov chain method, we derive queue length distribution at departure epochs. We also obtain the queue length distribution at an arbitrary time by the supplementary variable method. Finally, performance measures such as loss probability and mean waiting time are presented.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.4
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• pp.39-44
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• 2014

IMS(IP Multi-Media Subsystem) base on the IP service platform which can offer multimedia as the voice, audio, video, and data is service platform. In 3G mobile communication in the early day, IMS had a suggestion for supporting to multimedia service in the 3GPP. But now It is broadly substituting in the IPTV, wire phone company and it is substituted in internet platform base on the soft-switch in currently. Especially nowadays, 4G LTE in a mobile communication company is rapidly growing in market. Therefore, in this study, we had designed to the main prosser that can admit to 1,000 user over and SIP gateway which can link the IMS 코어 that can link SIP Device which adopt the standard protocol on the SIP.

• Journal of the Korean Operations Research and Management Science Society
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• v.19 no.3
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• pp.235-241
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• 1994

We consider a B/G/1 queueing with vacations, where the server closes the gate when it begins a vacation. In this system, customers arrive according to a Bernoulli process. The service time and the vacation time follow discrete distributions. We obtain the distribution of the number of customers at a random point in time, and in turn, the distribution of the residence time (queueing time + service time) for a customer. It is observed that solutions for our discret time B/G/1 gated vacation model are analogous to those for the continuous time M/G/1 gated vacation model.

• Food Science of Animal Resources
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• v.31 no.3
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• pp.477-483
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• 2011

In this study, the most preferred trans fatty acid analysis methods, AOAC 996.06 and the Korea Food and Drug Administration official method, were reviewed and modified to apply to dairy products and dairy products imported into the Republic of Korea for evaluating trans fatty acid (TFA) content. The Rose-Gottlieb method for total fat analysis was validated with accuracy and precision parameters by analyzing infant formula standard reference material provided by the National Institute for Standards and Technology. The accuracy and precision data satisfied the CODEX guidelines. TFAs were analyzed with a resolution of 1.5 for 45 min using the modified oven temperature program. This modified method was applied to 45 dairy products from 11 countries. Average TFA contents in these imported dairy products ranged from 0.1 to 5.4 g per 100 g product. The majority of dairy products imported into the Republic of Korea were cheeses. TFA contents in the cheeses were 0.1 to 2.4 g per 100 g cheese. TFA contents in other dairy products were 1.7 to 5.4 g per 100 g product. These TFAs content variations can be explained by the trans fatty acids naturally present in ruminant milk formed by bacterial bio-hydrogenation in the rumen of cows and the different vegetable fat used as ingredients in the final products.

• Korean Journal of Veterinary Service
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• v.14 no.1
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• pp.13-17
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• 1991

This studies were carried out to investigate the changes of blood pictures within 24hrs after birth in Korean native calves. The hematologic values were examined from 300 heads healthy Korean native calves in the area of western farm of Chungnam province. The results obtained are summarized as follows : 1. $Mean{\pm}SD$ values of serum total protein contents within 24 hrs after birth in Korean native calves were $8.42{\pm}0.92g$ / dl and 48.14{\pm}0.93g$ / dl, respectively. 2. $Meant{\pm}SD$ values of RBC count, WBC count, PCV and Hb contents within 24 hrs after birth in Koren native natives were 49.97{\pm}2.56{\times}10^3$ / mm^3$ and $9.88{\pm}2.93{\times}10^3/ mm^3, $ 439.56{\pm}15.42%$ and 441.66{\pm}7.09 %, $$ 12.79{\pm}1.59g$ / dl and 13.$63{\pm}1.87g$ / dl, respectively. 3. 4Meant{\pm}SD$ values of MCV, MCH and MCHC within 24 hrs after birth in Koren native calves were $43.41{\pm}3.09{\mu}mm^3$ and $43.88{\pm}3.31{\mu}mm^3, $ $14.05{\pm}1.22pg $and 414.36{\pm}1.6pg, $ $32.46{\pm}2.47g$ / dl and 432.96{\pm}3.17g$ / dl, respectively.

• Journal of the Korean Society of Food Culture
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• v.29 no.3
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• pp.278-285
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• 2014

This study investigated the quality characteristics of fermented wines using a selected strain to obtain basic data on sugar-free tomato wine production. Alcohol content of the tomato and commercial wine was 8.2~12.9%, whereas tomato wine showed a relatively low alcohol content of 8.2%. For total phenol content, Chile wine showed the highest value of 162.89 mg/100 g, followed by persimmon wine at 122.33 mg/100 g. Tomato wine showed a relatively high total phenol content of 96.57 mg/100 g. In all sections, xylose was not detected, although there were differences in free sugars depending on each product. Acetic and citric acid contents were highest in tomato wine, and the six kinds of commercial wine and tomato wine showed acetic acid content of 800.6 mg/100 g and citric acid content of 1,064.4 mg/100 g. The total free amino acid content was 100.63 mg/100 g in tomato wine, which was 2~3 times higher compared to that in commercial wine ($26.33{\pm}52.15mg/100g$).

• Journal of Food Hygiene and Safety
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• v.26 no.1
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• pp.1-11
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• 2011

Nivalenol (NIV), deoxynivalenol (DON), T-2 toxin (T-2) and zearalenone (ZEN) are mycotoxins produced by some Fusarium species known to be very frequently contaminated in feed. The study for simultaneous analysis and contamination survey in animal feed carried out. All mycotoxins were analysed by using high performance liquid chromatography tandem mass with internal standard. The limits of detection (LOD) were $2.0\;{\mu}g/kg$, $1.0\;{\mu}g/kg$, $1.0\;{\mu}g/kg$ and $0.1\;{\mu}g/kg$ for NIV, DON, T-2 and ZEN, respectively. Two hundred and thirty nine samples of feed were collected. The average concentration of DON was $212.3\;{\mu}g/kg$, $207.8\;{\mu}g/kg$ and $812.1\;{\mu}g/kg$ in chicken, pig and cattle feed, respectively. The average concentration of ZEN was $31.2\;{\mu}g/kg$, $35.6\;{\mu}g/kg$ and $147.2\;{\mu}g/kg$ for them, respectively. Especially, the levels of contamination for DON and ZEN were higher than those of NIV or T-2. And, the levels of contamination for four Fusarium mycotoxins in cattle feed appeared higher than those of pig and chicken feed. It was investigated that the high level of mycotoxin contamination in cattle feed was caused by com gluten feed of ingredients for feed, mainly.

• Journal of Internet Computing and Services
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• v.20 no.3
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• pp.129-135
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• 2019

Recently, it is anticipated that 5G network would play the significant role of the neural network for 4th generation industry revolution and create huge value for the new market. However, in spite of proliferating prospect of 5G network industry and leading position in the launch of 5G, network operators have hesitated to give their full support to establishing proper network. Due to the lack of business models promoting 5G industry, network operators feel that they will not realize the return from the exorbitant investment in 5G network establishment. Moreover, the rigorous research efforts to investigate and analyze the various business environments regarding 5G rarely exists. Therefore, the purpose of the research is to holistically propose the research issues related to the technology, service providing method, governmental policy, and business models in commercializing and promoting 5G network.

• The Plant Pathology Journal
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• v.31 no.3
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• pp.316-321
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• 2015

A small cationic peptide (JH8944) was tested for activity against a number of pathogens of agricultural crops. JH8944 inhibited conidium growth in most of the tested plant pathogens with a dose of $50{\mu}g/ml$, although one isolate of Fusarium oxysporum was inhibited at $5{\mu}g/ml$ of JH8944. Most conidia of Fusarium graminearum were killed within 6 hours of treatment with $50{\mu}g/ml$ of JH8944. Germinating F. graminearum conidia required $238{\mu}g/ml$ of JH8944 for 90% growth inhibition. The peptide did not cause any damage to tissues surrounding maize leaf punctures when tested at a higher concentration of $250{\mu}g/ml$ even after 3 days. Liposomes consisting of phosphatidylglycerol were susceptible to leakage after treatment with 25 and $50{\mu}g/ml$ of JH8944. These experiments suggest this peptide destroys fungal membrane integrity and could be utilized for control of crop fungal pathogens.

• Korean Journal of Veterinary Service
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• v.23 no.1
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• pp.1-8
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• 2000

This study was carried out to simultaneous determination of penicillin G and chloramphenicol in livestock products by HPLC. The results obstained were as follows; 1. Penicillin G and chloramphenicol were analyzed by HPLC on symmetry $C_{18}$ column with acetonitrile-0.1 M phosphate buffer containing 0.0157 M thiosulfate (25 : 75) as mobile phase at UV 325nm and 280nm, respectively. 2. Samples were applied to a SeP-Pak $C_{18}$ cartridge, from which eluted penicillin derivatized with 2 M 1,2,4-triazole containing 0.001 M mercuric chloride. 3. The average recovery rates of penicillin G and chloramphenicol were 81.8% and 80.3%, respectively, and the detection limits were 5 ppb (5$\mu\textrm{g}$/kg: 7.9IU/kg) for penicillin G and chloramphenicol in porcine and bovine muscle.