• Resources Recycling
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• v.14 no.2
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• pp.33-42
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• 2005

Solvent extraction experiments have been performed to separate Nd and Sm from chloride solution with PC88A. The effect of the saponification of PC88A on the extraction and separation of the two metals were studied. In the experimental ranges conducted in this study, the distribution coefficients of Sm were higher than those of Nd and separation factor between them increased with the equilibrium pH of aqueous solution. Saponification of PC88A enhanced the distribution coefficients of Sm and Nd and the separation factor. A chemical model was developed to predict the distribution coefficients of metals and separation factor from the initial extraction conditions. The measured distribution coefficients of Nd and Sm with PC88A and saponified PC88A agreed well with those calculated in this study.

• Composites Research
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• v.34 no.1
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• pp.1-7
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• 2021

Fiber-reinforced thermoplastic composites are applied to transport industries to lightweight of body, and applications will be expanded gradually. In this study, the impregnation and mechanical properties of continuous glass fiber (GF) reinforced polycarbonate (PC) composites were evaluated with different molecular weights of PC. The continuous GF reinforced PC composite were prepared by using GF fabric and PC film via continuous compression molding method. The melting flow index and tensile strength of PC matrix were evaluated with different molecular weights. Mechanical properties (tensile, flexural, and compressive) and pore rate of GF/PC composite were evaluated with different molecular weights of PC. The fracture behavior was analyzed to fracture surface of GF/PC composite using FE-SEM images. As these results, it was condition of representing the best mechanical property that the GF/PC composite was prepared by using PC of 20,000 g/mol as matrix.

• Korean Journal of Environmental Agriculture
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• v.40 no.4
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• pp.359-365
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• 2021

BACKGROUND: Prohexadione-calcium (PC) is a plant growth regulator of cyclohexanedione family acting on inhibiting gibberellin biosynthesis and has been used to regulate shoot elongation of turfgrass in the golf course during the summer season. This study was conducted to investigate the effects of PC on the inhibition of shoot elongation, growth, and nitrogen uptake in Zoysia matrella. METHODS AND RESULTS: Treatments were as follows; non-treatment, control (TE 0.01 a.i. g/m²/100 mL), 0.0025PC (PC 0.0025 a.i. g/m²/100 mL), 0.005PC (PC 0.005 a.i. g/m²/100 mL), 0.01PC (PC 0.01 a.i. g/m²/100 mL) and 0.02PC (PC 0.02 a.i. g/m²/100 mL). Visual quality and chlorophyll content were not significantly different. As compared to non-treatment, shoot length and clipping yield in 0.005PC, 0.01PC and 0.02PC treatments were decreased by 29-36% and 65-82%, respectively, and those of 0.0025PC were not significantly different. N uptake of Z. matrella after applying PC was decreased by 28.9-77.8% than that of non-treatment. Inhibition effects of PC treatment in Z. matrella were not significantly different from those of control. CONCLUSION(S): These results indicated that the application of prohexadione calcium inhibited shoot elongation, clipping yield and N uptake amount in Z. matrella, and trinexapac-ethyl could be replaced with prohexadione-calcium in turfgrass management.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.122-125
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• 1998

본 논문에서는 인터넷텔레포니 인터페이스(Internet Telphone Interface)를 제작하고 자체 개발된 PC-to-PC 방식의 인터넷 전화 소프트웨어인 Realphone을 이용하여 Phone-to-PC 방식의 인터넷 전화를 구현하였다. 실험을 위하여 인터넷텔레포니 인터페이스를 제작하였으며, 펜티엄 PC 2대와 일반 상용화 되어있는 전화기를 사용하였다. 통화는 목원대학교 학내전화와 목원대학교내 LAN으로 연결된 PC사이에 로컬(Local)상황과 국내 교육망으로 연결된 목원대학교와 서울대학교 사이에 트래픽이 서로 다른 새벽(Unload), 오전(Mid-load), 오후(Load)에 이루어졌다. 실험을 통하여 대형 게이트웨이의 도움없이 간단한 인터페이스만으로 Phone-to-PC 방식 인터넷전화의 통화가 가능함을 확인하였다.

• KIPS Transactions on Computer and Communication Systems
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• v.6 no.7
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• pp.307-314
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• 2017

Stick-PC is small and portable, So it can be used like a desktop if you connect it to a display device such as a monitor or TV anytime and anywhere. Accordingly, Stick-PC can related to various crimes, and various evidence may remain. Stick-PC uses the same Windows version of the operating system as the regular Desktop, the artifacts to be analyzed are the same. However, unlike the Desktop, it can be used as a meaningful information for forensic investigation if it is possible to identify the actual user and trace the usage by finding the traces of peripheral devices before analyzing the system due to the mobility. In this paper, We presents a method of collecting images using Bootable OS, which is one of the image collection methods of Stick-PC. In addition, we show how to analyze the trace of peripheral connection and network connection trace such as Display, Bluetooth through the registry and event log, and suggest the application method from the forensic point of view through experimental scenario.

• Journal of Food Hygiene and Safety
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• v.6 no.3
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• pp.119-126
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• 1991

ABSTRACT - This study was performed to investigate the possible effect of Lactobacillus spp. on the growth and citrinin production by Penicillium citrinum. Lactobacillus bulgaricus and Lactobacillus casei were grown with Pen. citrinum in modified APT broth containing 7% of glucose and incubated at $30^{\circ}C$ for 15 days. Four inoculation procedures were used; (a) Lactobacillus spp. and Pen. citrinum were grown alone(Pc, Lb, and Lc), (b) both organisms were added simultaneously(ST; Pc+Lb and Pc+Lc), (c) Lactobacillus spp. was grown 3 days, then conidia of Pen. citrinum were added(LbPc and LcPc), and (d) Pen. citrinum was grown 3 days, then Lactbacillus spp. was added (PcLb and PcLc). At 0, 3, 6, 9, 12, 15 days of incubation, the growth of each organism, pH and total acidity of broth, and content of citrinin were determined. Lactobacillus spp. and Pen. citrinum, when grown associatively, influenced the growth of each other. It was observed that slower growth of Pen. citrinum when in the presence of Lactobacillus spp. than when the mold grew alone. Production of citrinin by Pen. citrinum was markedly less in the mixed culture. No apparent growth and toxin production was observed when the Lactobacillus spp. was grown 3 days, then conidia of Pen. citrinum were added(LbPc and LcPc). The above results indicate that another microorganism or competing microflora in the culture can affect the behavior of Pen. citrinum.trinum.

• The KIPS Transactions:PartD
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• v.8D no.5
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• pp.523-532
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• 2001

An atomic commitment protocol ensures that distributed transcations terminate consistently at participating sites. An atomic commitment protocol is said to be non-blocking if it permits transaction termination to proceed at correct participants despite of failure in the coordinator site and communication. It is well known that the famous two phase commit(2PC) is a blocking protocol, whereas the three phase commit(3PC) protocol is a non-blocking. In this paper, we propose a non-blocking two phase commit(NB-2PC) protocol reducing the blocking problem than propose non-blocking protocols. The NB-2PC protocol can be obtained through modifications of the 2PC protocol. After receiving Prepare message from coordinator in the NB-2PC protocol, participants respond to the coordinator and several participants in voting phase. While participants wait for decision message from the coordinator, the blocking occurs due to the failure of the coordinator site, participants elect new coordinator among several participants receive response message. Despite of the coordinator site failures, participants consult new coordinator and follow termination protocols and achieve non-blocking property. We propose a basic structure of NB-2PC protocol and termination protocol and new coordinator election protocol. The NB-2PC protocol has non-blocking property and reduces processing time of commit protocol than the 3PC protocol. Also, through simulation experiments, we propose the NB-2PC protocol exhibits better performance of processing time of commit protocol than 3PC protocol.

• Journal of The Korean Association of Information Education
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• v.15 no.1
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• pp.111-117
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• 2011

Many various researches about the PC execution process monitoring system have studied. Nevertheless, it is hard to find research of a system that multi-PC based each PC can be monitoring and reporting by file type. In this study, it designed and implemented that each PC can be monitoring and reporting by files to a server in multi-PCs' environments. Moreover it can gather and organize informations of reporting. It is expected users can recognize that execution processes are reporting. It causes to reduce execution unnecessary process.

• Journal of Digital Contents Society
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• v.9 no.4
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• pp.717-723
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• 2008

Many of the domestic PC manufactures and professional PC repair shops are suffering from lack of efficient diagnostic database systems or CAD tools for diagnosis and repair of PCs. In order to solve this problem, a new diagnostic database system for PC maintenance and repair is presented in this paper. We can perform accurate and rapid diagnosis for the PCs with software and hardware troubles by using proposed database system and thus the number of customers who are satisfied with service results are to be increased. Furthermore our research outputs make it possible the experts in PC repair field accumulate maintenance techniques and enhance the reliability of performance evaluated by customers.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.11b
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• pp.1037-1040
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• 2003

본 논문에서는 LAN 상에서 유휴 PC 들을 연산에 활용하는 PC Cluster 시스템에 대해 연구하였다. 특히, PC 실습실에 있는 PC 들의 유휴시간(Idle time)대를 이용하여 Cluster 연산에 사용함으로써 별도의 전용 클러스터 시스템을 설치하기 위한 하드웨어 및 설치 공간이 필요로 하지 않는다는 장점을 갖는다. PC 실습실의 PC 들은 주간에는 주로 교육 및 실습에 사용되며 오후 6시부터 오전 9시까지의 실습에 사용되지 않는 유휴시간을 CPU-Intensive 한 작업들을 병렬로 수행하는 PC Cluster로 구성하여 저가격의 고성능 시스템을 구축할 수 있다. 그리고 특정 연산을 전담하는 노드들을 지정하고 이 노드들의 연산 결과를 인접한 다른 노드들에게 전달함으로써 연속적인 다음 연산을 적용할 수 있도록 파이프라인(Pipeline) 형태로 구성한다. 파이프라인 형태의 PC Cluster 에서 연산을 겹침(Overlapped)으로서 처리량(Throughput)을 높일 수 있다. LAN으로 연결된 PC 실습실의 PC 들은 인터넷상의 연산 자원들보다 안정되고 신뢰성이 있기 때문에 복잡한 보안 기법을 사용하지 않아도 된다. 또한 연산시간이 유휴시간으로 고정되어 있기 때문에 네트워크의 부하 및 노드의 부하를 고려하는 복잡한 부하균등화 기법이나 스케줄링 기법이 필요로 하지 않는다.