• Journal of the Korea Society of Computer and Information
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• v.10 no.5 s.37
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• pp.187-198
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• 2005

In this paper, we propose the enhanced header compression scheme for the efficient data traffic transmission in Ipv6 networks. The bandwidth of wireless links and IP networks will probably be limited due to properties of the physical medium and regulatory limits on the use of frequencies for radio communications. That is major cause of user throughput reduction. Therefore, We discuss the IPHC(RFC2507) and ROHC(RFC3095) scheme. IPHC is simple header compression scheme and ROHC is enhanced header compression that have fast optimal recovery scheme. We have studied the enhanced header compression scheme in ROHC. We will show that indication of compression context values preventing from packet losses can provide the fast recovery of compression state. Computer simulations show that the proposed scheme has better performance than the previous one.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.515-518
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• 2011

Recently we all agree with the fact that conference is the most important communication method in industrial fields. With improvement of information technology, the conference using computer-aided system has been increased. Therefore, software, which can support the conference, is highly needed. In our work, we implemented the display sharing system in WLANs that sends the presenter's display to all audience in real-time manner. In order to share the display, we used multicast transmission which shows good performance in one to many communications. And also, to solve the data error and loss problem, which are weak points of multicast transmission, we used Reed-Solomon coding scheme.

• Asian-Australasian Journal of Animal Sciences
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• v.1 no.4
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• pp.213-218
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• 1988

Forty eight growing bulls of two breed types(red Sahiwal and white Kilari), fed rice straw, were allocated to nine treatment groups: 1. Control straw (CS) 2. Urea upgraded straw (UUS) 3. UUS + 0.25 kg coconut cake (CC) 4. UUS + 0.75 kg CC 5. UUS + 0.25 kg rice bran (RB) 6. UUS + 1.00 kg RB 7. UUS + 0.25 kg RB + 0.25 kg CC 8. UUS + 1.00 kg RB + 0.25 kg CC 9. CS + 1.00 kg RB + 0.25 kg CC Liveweight gain was measured weekly during 15 weeks and tested in three analyses of variance. The results are: Urea upgraded straw produced a liveweight gain $180g.d^{-1}$ higher (P <0.01) than control straw. The groups supplemented with 0.25 kg coconut cake and 1.00 kg rice bran showed an increase of $100g.d^{-1}$ (p < 0.05) over the unsupplemented groups. No interaction between straw upgrading and supplementation was present (P > 0.10). Both rice bran and coconut press cake, supplemented to upgraded straw at a level of 0.25 kg, did not increase liveweight gain (P>0.05), but 1.0 kg rice bran increased gain by $90g.d^{-1}$ (P<0.05). A supplement of 0.75 kg coconut press cake to upgraded straw increased liveweight gain by $160g.d^{-1}$ compared with 0.25 kg or 0.00 kg coconut cake supplement (P<0.05). There were no significant differences between breed types (P>0.10) or interactions between breed and the other two main treatments (upgrading and supplementation). It was concluded. that both urea upgrading and supplementation of rice straw increase animal performance. The effect of urea upgrading was the same for both supplemented and unsupplemented animals. There was no indication of a nonlinear effect of supplements on growth.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.558-570
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• 2014

This study was conducted to compare the volatile flavor compounds found in the leaves of 15 taxa of Korean native Chrysanthemum species. The volatile flavor compounds from the taxa were collected using a simultaneous steam distillation and extraction technique and were analyzed using gas chromatography/mass selective detector (GC/MSD). A total of 45 volatile flavor compounds were identified with six functional groups: 14 alcohols, 4 ketones, 19 hydrocarbons, 5 esters, 2 acids, and 1 aldehyde. The main functional group in 15 taxa of Chrysanthemum species was alcohols, accounting for 28.7% of volatile flavor compounds, followed by ketones (21.2%) and hydrocarbons (13.2%). Camphor, which is known for its antimicrobial properties, was the most abundant volatile compound (30%) in C. zawadskii ssp. latilobum and var. leiophyllum. In particular, C. indicum subspecies and C. boreale contained ${\alpha}$-thujone, which has outstanding anti-bacterial, anti-cancer, anti-inflammatory, anti-ulcer, and anti-diabetic efficacies. C. indicum var. albescens could be used in perfumes, since it showed 21 times more camphene than C. indicum. In addition, C. indicum var. acuta contained a fairly high content of 1,8-cineole, which has an inhibitory effect on mutagenesis. C. lineare contained only pentadecanoic acid compounds, whereas other taxa hexadecanoic acids. Overall, the Korean native Chrysanthemum species had considerable variation in volatile flavor compounds in their leaves. This study provides a good indication of specific potential use for various applications.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.8
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• pp.1195-1202
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• 2010

When modelling lots of induction motors to design and configure an engine room simulator, the 2 parameters equivalent circuit has many practical benefits as it reduces working hours considerably without requiring complicated technical data from makers except the ratings of motors. The basic properties such as torque and load current are shown well matched with real cases by this method, but almost the only drawback of 2 parameters circuit is that it reveals inherently higher power factor in the whole operation range due to disregarding the exciting current of the induction motor to maximize the simplification. This paper suggests a modelling module as a practical tool to compensate the power factor by inserting a virtual compensation current into the load current from 2 parameters equivalent circuit, and the simulated results show satisfactory outputs and the improved power factor indication by performance curves when compared to the cases of 2 parameters-equivalent circuit.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.395-395
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• 2000

Optimization of existing processes becomes more important than the past as environmental problems and concerns about energy savings stand out. When we can model a process mathematically, we can easily optimize it by using the model as constraints. However, modeling is very difficult for most chemical processes as they include numerous units together with their correlation and we can hardly obtain parameters. Therefore, optimization that is based on the process models is, in turn, hard to perform. Especially, f3r unknown processes, such as bioprocess or microelectronics materials process, optimization using mathematical model (first principle model) is nearly impossible, as we cannot understand the inside mechanism. Consequently, we propose a few optimization method using empirical model evolutionarily instead of mathematical model. In this method, firstly, designing experiments is executed fur removing unecessary experiments. D-optimal DOE is the most developed one among DOEs. It calculates design points so as to minimize the parameters variances of empirical model. Experiments must be performed in order to see the causation between input variables and output variables as only correlation structure can be detected in historical data. And then, using data generated by experiments, empirical model, i.e. response surface is built by PLS or MLR. Now, as process model is constructed, it is used as objective function for optimization. As the optimum point is a local one. above procedures are repeated while moving to a new experiment region fur finding the global optimum point. As a result of application to the pulp digester benchmark model, kappa number that is an indication fur impurity contents decreased to very low value, 3.0394 from 29.7091. From the result, we can see that the proposed methodology has sufficient good performance fur optimization, and is also applicable to real processes.

• Fashion & Textile Research Journal
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• v.6 no.6
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• pp.810-814
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• 2004

This study is one of the fundamental researches for the development of future smart clothing and textile products using silver(Ag) nano powder. Our study was focused on the blocking or insulating effects of nano-processed textiles from electromagnetic waves. Also, for the surveying of the actual effect to human body, we measure the variation of electroencephalogram which is an indication of human physical symptoms. Among various textiles in this experiment, nano silver processed case has shown the best blocking performance from the electromagnetic waves, which decreases depending on the distance. As a reference model of working environment, we setup the visual stimuli object on the computer that is a source of electromagnetic wave. The power spectrum distribution and the incidence of electroencephalogram was measured. The analysed data has shown that, with nano-processed textiles, ${\beta}$ wave does not appear very often where ${\beta}$ wave appears only to illustrate the stable states of human's body. However, as for the materials without nano processing, the ratio of ${\gamma}$ waves in the total level of electroencephalogram becomes higher in spite of short exposure to visual stimuli in work environment, which shows that the worker becomes stressed. The ${\beta}$ wave electroencephalogram of all materials is drawn in calcarine fissure of occipital lobe to show the convergent distribution, and stronger with block-processed Nano Silver Silk(NSS). The study based on the potential risks of human diseases such as physical fatigue by electromagnetic waves, and has shown that the application of Nano Silver textile for human uses require a proper particle size of it which would not penetrate cellular tissues, and a proper binder and binding treatment for it. However, it is highly required for back-up researches to verify various aspects in applying nano silver to textile products.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.8B
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• pp.514-524
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• 2005

In optical burst switching(OBS) networks, the ingress edge router assembles packets in the same class queue into the appropriate size of burst. A burst control packet(BCP) is generated for channel reservation of corresponding data burst and sent earlier than the corresponding data burst with an offset time. Offset time is determined considering the number of hops from source to destination and the required quality of service(QoS). After offset time, the burst data is passed through tile pre-configured optical switches without any O/E/O conversion. But a failure in OBS networks may lead to the loss of bursts until the ingress nodes receive the failure indication signal. This results in a significant degradation in QoS. Therefore, in this paper, we propose a fault-tolerant node architecture based on sub-carrier multiplexing to reduce the effects of failure in OBS networks. The Performance of the proposed fault-tolerant node architecture exhibits considerable improvement as compared with the previous ones.

• YAKHAK HOEJI
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• v.53 no.3
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• pp.107-113
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• 2009

Since 2006, the Computerized Restricted Antibiotic Control Program (CRACP) has been incorporated to facilitate a more efficient approval process of vancomycin use at the Chonbuk National University Hospital. The purposes of the study were to evaluate proper use of vancomycin and to examine if there is any improvement when administering the CRACP. The use of vancomycin was retrospectively reviewed by a medical record review based on the American Society of Hospital Pharmacists (ASHP) criteria (i.e., indication, use of critical process indicators and use of outcome measurements) and compared before (Group I) and after the CRACP (Group II). Two hundred fifty six patient records were evaluated (138 in Group I and 118 in Group II). There was a statistically significant improvement in the report of justification for vancomycin use after CRACP (42.0% vs. 62.7%, p=0.001). Out of eight critical process indicators, two indicators (appropriate cultures prior to medication [68.8% vs. 85.6%, p=0.002] and serum vancomycin level measurement [0% vs. 7.6%, p=0.001]) were significantly improved after CRACP. The total incidence of adverse effects was decreased from 14.5% to 6.8%. In addition, there was a statistically significant difference in WBC count reduction within normal range (52.8% vs. 73.1%, p=0.024). The CRACP appears to be a promising approach to improve use of vacomycin in a hospital setting. However, further evaluation for the long-term period should be performed to confirm the performance of the program.

• The Journal of the Acoustical Society of Korea
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• v.24 no.8
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• pp.431-440
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• 2005

The precise measurement of ultrasonic power is important to the qualify assurance and the safety of medical ultrasonic equipments In the Present work, a brier theory was introduced to determine the ultrasonic Power from the time valving balance-indication due to the radiation force acting on an absorbing target and/or other causes such as buoyancy during the repetition of on/off behavior of ultrasonic irradiation. The developed automated system measuring the ultrasonic power was described in detail with the precise mechanical alignment tool , the electric signal generation network, the control and measurement network and the appropriate procedure. The ultrasonic power measured by the developed system was compared to the reference data calibrated by the other national metrology institute at 1 MHz, 5 MHz, 10 MHz, and 15 MHz over the range 10 mW to 10 W. Their relative differences are within $5\%$.